Background
Reconstruction of posttraumatic bone defects represents a difficult challenge. The induced membrane technique is an effective two-stage procedure for bone defect reconstruction. To ...overcome the problems of autologous bone grafting, different graft substitutes have been investigated. The aim of the present study is to evaluate our clinical experience in reconstruction of critical posttraumatic bone defects using an induced membrane technique based on a combination of autologous graft and allograft (cancellous bone) enriched with platelet-rich plasma (PRP) and bone marrow concentrate aspirate (BMCA).
Materials and methods
Between 2009 and 2014, we reconstructed 18 posttraumatic bone defects in 16 patients. Their average length was 6.4 cm (range 1.6–13.2 cm). The defect location was the femur in nine cases (50%), the tibia in eight (44%) cases, and the humerus in one (6%) case. In all cases, we used a combination of autologous and cancellous allograft graft enriched with PRP and BMCA. Bone fixation was achieved using intramedullary nailing in 2 cases (11%), plating in 15 cases (66%), and external fixation in 1 case (6%).
Results
Both clinical and radiographic union were achieved in 13 (72%) cases (13 patients). Five (28%) cases (four patients) developed nonunion. Nonunion was observed in two of eight (25%) tibial defects and in three (33%) of nine femoral defects (ns). Three of 4 (75%) double defects had delayed union, whereas 2 of 14 (14%) single defects did not heal (
p
= 0.016). The average length of the 13 defects that united was 6 cm (range 1.6–11.8 cm), while the length of the 5 defects that did not unite was 10.3 cm (range 6–13.2 cm) (
p
= 0.009).
Conclusions
In this series using an induced membrane technique based on a combination of autograft and allograft enriched with BMCA and PRP, the healing rate was lower than in other series where autologous bone graft alone was employed. Nonunion was more frequent in longer and double defects. Further research aimed at developing effective alternative options to autogenous cancellous bone graft is desirable.
Level of evidence
: III
Gaia Data Release 3 Arenou, F.; Lammers, U. L.; Mignard, F. ...
Astronomy and astrophysics (Berlin),
06/2023, Letnik:
674, Številka:
A1
Journal Article, Web Resource
Recenzirano
Odprti dostop
Context.
We present the third data release of the European Space Agency’s
Gaia
mission,
Gaia
DR3. This release includes a large variety of new data products, notably a much expanded radial velocity ...survey and a very extensive astrophysical characterisation of
Gaia
sources.
Aims.
We outline the content and the properties of
Gaia
DR3, providing an overview of the main improvements in the data processing in comparison with previous data releases (where applicable) and a brief discussion of the limitations of the data in this release.
Methods.
The
Gaia
DR3 catalogue is the outcome of the processing of raw data collected with the
Gaia
instruments during the first 34 months of the mission by the
Gaia
Data Processing and Analysis Consortium.
Results.
The
Gaia
DR3 catalogue contains the same source list, celestial positions, proper motions, parallaxes, and broad band photometry in the
G
,
G
BP
, and
G
RP
pass-bands already present in the Early Third Data Release,
Gaia
EDR3.
Gaia
DR3 introduces an impressive wealth of new data products. More than 33 million objects in the ranges
G
RVS
< 14 and 3100 <
T
eff
< 14 500, have new determinations of their mean radial velocities based on data collected by
Gaia
. We provide
G
RVS
magnitudes for most sources with radial velocities, and a line broadening parameter is listed for a subset of these. Mean
Gaia
spectra are made available to the community. The
Gaia
DR3 catalogue includes about 1 million mean spectra from the radial velocity spectrometer, and about 220 million low-resolution blue and red prism photometer BP/RP mean spectra. The results of the analysis of epoch photometry are provided for some 10 million sources across 24 variability types.
Gaia
DR3 includes astrophysical parameters and source class probabilities for about 470 million and 1500 million sources, respectively, including stars, galaxies, and quasars. Orbital elements and trend parameters are provided for some 800 000 astrometric, spectroscopic and eclipsing binaries. More than 150 000 Solar System objects, including new discoveries, with preliminary orbital solutions and individual epoch observations are part of this release. Reflectance spectra derived from the epoch BP/RP spectral data are published for about 60 000 asteroids. Finally, an additional data set is provided, namely the
Gaia
Andromeda Photometric Survey, consisting of the photometric time series for all sources located in a 5.5 degree radius field centred on the Andromeda galaxy.
Conclusions.
This data release represents a major advance with respect to
Gaia
DR2 and
Gaia
EDR3 because of the unprecedented quantity, quality, and variety of source astrophysical data. To date this is the largest collection of all-sky spectrophotometry, radial velocities, variables, and astrophysical parameters derived from both low- and high-resolution spectra and includes a spectrophotometric and dynamical survey of SSOs of the highest accuracy. The non-single star content surpasses the existing data by orders of magnitude. The quasar host and galaxy light profile collection is the first such survey that is all sky and space based. The astrophysical information provided in
Gaia
DR3 will unleash the full potential of
Gaia
’s exquisite astrometric, photometric, and radial velocity surveys.
Gaia Early Data Release 3 Brown, A. G. A.; Prusti, T.; Eyer, L. ...
Astronomy and astrophysics (Berlin),
05/2021, Letnik:
649
Journal Article, Web Resource
Recenzirano
Odprti dostop
Context.
We present the early installment of the third
Gaia
data release,
Gaia
EDR3, consisting of astrometry and photometry for 1.8 billion sources brighter than magnitude 21, complemented with the ...list of radial velocities from
Gaia
DR2.
Aims.
A summary of the contents of
Gaia
EDR3 is presented, accompanied by a discussion on the differences with respect to
Gaia
DR2 and an overview of the main limitations which are present in the survey. Recommendations are made on the responsible use of
Gaia
EDR3 results.
Methods.
The raw data collected with the
Gaia
instruments during the first 34 months of the mission have been processed by the
Gaia
Data Processing and Analysis Consortium and turned into this early third data release, which represents a major advance with respect to
Gaia
DR2 in terms of astrometric and photometric precision, accuracy, and homogeneity.
Results. Gaia
EDR3 contains celestial positions and the apparent brightness in
G
for approximately 1.8 billion sources. For 1.5 billion of those sources, parallaxes, proper motions, and the (
G
BP
−
G
RP
) colour are also available. The passbands for
G
,
G
BP
, and
G
RP
are provided as part of the release. For ease of use, the 7 million radial velocities from
Gaia
DR2 are included in this release, after the removal of a small number of spurious values. New radial velocities will appear as part of
Gaia
DR3. Finally,
Gaia
EDR3 represents an updated materialisation of the celestial reference frame (CRF) in the optical, the
Gaia
-CRF3, which is based solely on extragalactic sources. The creation of the source list for
Gaia
EDR3 includes enhancements that make it more robust with respect to high proper motion stars, and the disturbing effects of spurious and partially resolved sources. The source list is largely the same as that for
Gaia
DR2, but it does feature new sources and there are some notable changes. The source list will not change for
Gaia
DR3.
Conclusions. Gaia
EDR3 represents a significant advance over
Gaia
DR2, with parallax precisions increased by 30 per cent, proper motion precisions increased by a factor of 2, and the systematic errors in the astrometry suppressed by 30–40% for the parallaxes and by a factor ~2.5 for the proper motions. The photometry also features increased precision, but above all much better homogeneity across colour, magnitude, and celestial position. A single passband for
G
,
G
BP
, and
G
RP
is valid over the entire magnitude and colour range, with no systematics above the 1% level
Gaia Early Data Release 3 Lindegren, L.; Klioner, S. A.; Hernández, J. ...
Astronomy and astrophysics (Berlin),
05/2021, Letnik:
649
Journal Article
Recenzirano
Odprti dostop
Context. Gaia
Early Data Release 3 (
Gaia
EDR3) contains results for 1.812 billion sources in the magnitude range
G
= 3–21 based on observations collected by the European Space Agency
Gaia
satellite ...during the first 34 months of its operational phase.
Aims.
We describe the input data, the models, and the processing used for the astrometric content of
Gaia
EDR3, as well as the validation of these results performed within the astrometry task.
Methods.
The processing broadly followed the same procedures as for
Gaia
DR2, but with significant improvements to the modelling of observations. For the first time in the
Gaia
data processing, colour-dependent calibrations of the line- and point-spread functions have been used for sources with well-determined colours from DR2. In the astrometric processing these sources obtained five-parameter solutions, whereas other sources were processed using a special calibration that allowed a pseudocolour to be estimated as the sixth astrometric parameter. Compared with DR2, the astrometric calibration models have been extended, and the spin-related distortion model includes a self-consistent determination of basic-angle variations, improving the global parallax zero point.
Results. Gaia
EDR3 gives full astrometric data (positions at epoch J2016.0, parallaxes, and proper motions) for 1.468 billion sources (585 millionwith five-parameter solutions, 882 million with six parameters), and mean positions at J2016.0 for an additional 344 million.Solutions with five parameters are generally more accurate than six-parameter solutions, and are available for 93% of the sources brighter than the 17th magnitude. The median uncertainty in parallax and annual proper motion is 0.02–0.03 mas at magnitude
G
= 9–14, and around 0.5 mas at
G
= 20. Extensive characterisation of the statistical properties of the solutions is provided, including the estimated angular power spectrum of parallax bias from the quasars.
Summary of the contents and survey properties Brown, A.G.A.; Granvik, Mikael; Zwitter, T.
Astronomy and astrophysics (Berlin),
2018, 2018-01-01, Letnik:
16, Številka:
A1
Journal Article
Recenzirano
Odprti dostop
Context. We present the second Gaia data release, Gaia DR2, consisting of astrometry, photometry, radial velocities, and information on astrophysical parameters and variability, for sources brighter ...than magnitude 21. In addition epoch astrometry and photometry are provided for a modest sample of minor planets in the solar system. Aims. A summary of the contents of Gaia DR2 is presented, accompanied by a discussion on the differences with respect to Gaia DR1 and an overview of the main limitations which are still present in the survey. Recommendations are made on the responsible use of Gaia DR2 results. Methods. The raw data collected with the Gaia instruments during the first 22 months of the mission have been processed by the Gaia Data Processing and Analysis Consortium (DPAC) and turned into this second data release, which represents a major advance with respect to Gaia DR1 in terms of completeness, performance, and richness of the data products. Results. Gaia DR2 contains celestial positions and the apparent brightness in G for approximately 1.7 billion sources. For 1.3 billion of those sources, parallaxes and proper motions are in addition available. The sample of sources for which variability information is provided is expanded to 0 : 5 million stars. This data release contains four new elements: broad-band colour information in the form of the apparent brightness in the G(BP) (330-680 nm) and G(RP) (630-1050 nm) bands is available for 1.4 billion sources; median radial velocities for some 7 million sources are presented; for between 77 and 161 million sources estimates are provided of the stellar effective temperature, extinction, reddening, and radius and luminosity; and for a pre-selected list of 14 000 minor planets in the solar system epoch astrometry and photometry are presented. Finally, Gaia DR2 also represents a new materialisation of the celestial reference frame in the optical, the Gaia-CRF2, which is the first optical reference frame based solely on extragalactic sources. There are notable changes in the photometric system and the catalogue source list with respect to Gaia DR1, and we stress the need to consider the two data releases as independent. Conclusions. Gaia DR2 represents a major achievement for the Gaia mission, delivering on the long standing promise to provide parallaxes and proper motions for over 1 billion stars, and representing a first step in the availability of complementary radial velocity and source astrophysical information for a sample of stars in the Gaia survey which covers a very substantial fraction of the volume of our galaxy.
The Gaia mission Vallenari, A.; Bailer-Jones, C. A. L.; Milligan, D. J. ...
Astronomy and astrophysics (Berlin),
11/2016, Letnik:
595
Journal Article, Web Resource
Recenzirano
Odprti dostop
Gaia is a cornerstone mission in the science programme of the EuropeanSpace Agency (ESA). The spacecraft construction was approved in 2006, following a study in which the original interferometric ...concept was changed to a direct-imaging approach. Both the spacecraft and the payload were built by European industry. The involvement of the scientific community focusses on data processing for which the international Gaia Data Processing and Analysis Consortium (DPAC) was selected in 2007. Gaia was launched on 19 December 2013 and arrived at its operating point, the second Lagrange point of the Sun-Earth-Moon system, a few weeks later. The commissioning of the spacecraft and payload was completed on 19 July 2014. The nominal five-year mission started with four weeks of special, ecliptic-pole scanning and subsequently transferred into full-sky scanning mode. We recall the scientific goals of Gaia and give a description of the as-built spacecraft that is currently (mid-2016) being operated to achieve these goals. We pay special attention to the payload module, the performance of which is closely related to the scientific performance of the mission. We provide a summary of the commissioning activities and findings, followed by a description of the routine operational mode. We summarise scientific performance estimates on the basis of in-orbit operations. Several intermediate Gaia data releases are planned and the data can be retrieved from the Gaia Archive, which is available through the Gaia home page.
Context. Gaia Data Release 2 provides high-precision astrometry and three-band photometry for about 1.3 billion sources over the full sky. The precision, accuracy, and homogeneity of both astrometry ...and photometry are unprecedented. Aims. We highlight the power of the Gaia DR2 in studying many fine structures of the Hertzsprung-Russell diagram (HRD). Gaia allows us to present many different HRDs, depending in particular on stellar population selections. We do not aim here for completeness in terms of types of stars or stellar evolutionary aspects. Instead, we have chosen several illustrative examples. Methods. We describe some of the selections that can be made in Gaia DR2 to highlight the main structures of the Gaia HRDs. We select both field and cluster (open and globular) stars, compare the observations with previous classifications and with stellar evolutionary tracks, and we present variations of the Gaia HRD with age, metallicity, and kinematics. Late stages of stellar evolution such as hot subdwarfs, post-AGB stars, planetary nebulae, and white dwarfs are also analysed, as well as low-mass brown dwarf objects. Results. The Gaia HRDs are unprecedented in both precision and coverage of the various Milky Way stellar populations and stellar evolutionary phases. Many fine structures of the HRDs are presented. The clear split of the white dwarf sequence into hydrogen and helium white dwarfs is presented for the first time in an HRD. The relation between kinematics and the HRD is nicely illustrated. Two different populations in a classical kinematic selection of the halo are unambiguously identified in the HRD. Membership and mean parameters for a selected list of open clusters are provided. They allow drawing very detailed cluster sequences, highlighting fine structures, and providing extremely precise empirical isochrones that will lead to more insight in stellar physics. Conclusions. Gaia DR2 demonstrates the potential of combining precise astrometry and photometry for large samples for studies in stellar evolution and stellar population and opens an entire new area for HRD-based studies.
ABSTRACT
OBJECTIVES
Healthcare systems have a significant environmental impact and, thus, indirectly affect public health. In order to improve current practices, a better understanding of the ...actual environmental impact generated by surgical procedures is necessary.
METHODS
An eco-audit methodology was carried out to assess the greenhouse gas emissions arising from conventional isolated cardiac surgery procedures. This inquiry took into account 3 workstations (the surgical, the anaesthesia and the cardiopulmonary bypass workstations). All wastes were analysed including the disposable medical products, pharmaceuticals and energy consumption during such surgeries.
RESULTS
Twenty-eight cardiac surgeries were analysed out of a 4-week study period. The mean emissions during a single cardiac surgery was 124.3 kg of carbon dioxide equivalent (CO2-e). Eighty-nine per cent of the total emissions was related to the use of disposable medical products. The environmental impact of pharmaceuticals used at anaesthesia workstations was 12.4 kg of CO2-e (10% of total greenhouse gas emission), with 11.1 kg of CO2-e resulting from the use of halogenated gas. Direct electrical consumption resulted in 4.0 kg of CO2-e per surgery (3% of all emission), including lighting and air conditioning.
CONCLUSIONS
Conventional isolated cardiac procedures yield the global warming equivalent of a 1080 km plane ride for a single passenger. The environmental impact of such life-saving interventions, therefore, must be put in perspective alongside pollution induced by ‘non-indispensable’ human activities. However, numerous initiatives at the local and individual level as well as at a larger systemic and countrywide scale appear to provide accessible pathways to meaningfully reduce greenhouse gas emissions during cardiac surgery.
The health of our environment is a growing concern in modern society.
The possibility of achieving correct deep femoral tunnel positioning during anterior cruciate ligament (ACL) reconstruction with the double incision technique (DI), the transtibial technique (TT), ...and the anteromedial technique (AM) was evaluated in 30 cadaver knees. A reference hole was made just deep to the insertion of the anteromedial bundle of the ACL through an anteromedial arthrotomy. In the DI technique, a Kirshner wire was inserted outside-in using a rear entry C guide. In the TT and AM techniques, the K-wire was inserted inside-out through the tibial tunnel and through the arthrotomy, respectively. The reference hole could be achieved with each technique. Using lateral radiographs, the superficial aspect of the intra-articular exit of the femoral tunnel was found to be located on average at 36%, 36%, and 34% of the width of the condyles from the posterior margin (NS). None of the holes was more anterior than 40%. In conclusion, a deep femoral tunnel positioning could be achieved with each technique. The choice of technique must be based on the surgeon's preference and clinical results.
Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 15, No 7 (October), 1999: pp 750–756
Gaia Data Release 2 Bastian, U.; Babusiaux, C.; Breddels, M. A. ...
Astronomy and astrophysics (Berlin),
08/2018, Letnik:
616, Številka:
A12
Journal Article, Web Resource
Recenzirano
Odprti dostop
Context.
Aims.
The goal of this paper is to demonstrate the outstanding quality of the second data release of the
Gaia
mission and its power for constraining many different aspects of the dynamics of ...the satellites of the Milky Way. We focus here on determining the proper motions of 75 Galactic globular clusters, nine dwarf spheroidal galaxies, one ultra-faint system, and the Large and Small Magellanic Clouds.
Methods.
Using data extracted from the
Gaia
archive, we derived the proper motions and parallaxes for these systems, as well as their uncertainties. We demonstrate that the errors, statistical and systematic, are relatively well understood. We integrated the orbits of these objects in three different Galactic potentials, and characterised their properties. We present the derived proper motions, space velocities, and characteristic orbital parameters in various tables to facilitate their use by the astronomical community.
Results.
Our limited and straightforward analyses have allowed us for example to (
i
) determine absolute and very precise proper motions for globular clusters; (
ii
) detect clear rotation signatures in the proper motions of at least five globular clusters; (
iii
) show that the satellites of the Milky Way are all on high-inclination orbits, but that they do not share a single plane of motion; (
iv
) derive a lower limit for the mass of the Milky Way of 9.1
-2.6
+6.2
× 10
11
M
⊙
based on the assumption that the Leo I dwarf spheroidal is bound; (
v
) derive a rotation curve for the Large Magellanic Cloud based solely on proper motions that is competitive with line-of-sight velocity curves, now using many orders of magnitude more sources; and (
vi
) unveil the dynamical effect of the bar on the motions of stars in the Large Magellanic Cloud.
Conclusions.
All these results highlight the incredible power of the
Gaia
astrometric mission, and in particular of its second data release.
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