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Ophrys fusca and Ophrys dyris (Orchidaceae) – constancy of tetraploidy amongst populations in Central Portugal
Ophrys is amongst the best known orchid genera and is an established system for the study of pollinatormediated
floral evolution. Two species, Ophrys fusca s.l. and Ophrys dyris (= O. omegaifera subsp. dyris) belonging to Ophrys section Pseudophrys are the focus of this study. In the context of an integrative study of morphological and genetic diversity of O. fusca and O. dyris, genome size (GS) and cytotype diversity were surveyed from Portuguese populations. Flow cytometry methods were used to assess GS, and subsequently determine the ploidy level of 67 specimens, including the species and putative hybrids. Cytotypes were also confirmed based on chromosome counts from the roots of two specimens, one of
each species. Constancy of nuclear DNA content (1C = 11.19 pg) and ploidy level (2n =4x = 72, 74) was
documented among all the individuals analysed. Implications are considered, in terms of interpreting the
origin and predicting the persistence of putative hybrids
Observations of the Antarctic polar front during FDRAKE 76 : a cruise report
Figures 37 and 38 have been reduced from their original size for the purpose of scanning.During March/April 1976 the small-scale structure of the Antarctic Polar Front was observed in the Drake Passage. The
observations were part of the International Southern Ocean Studies (ISOS) program called FDRAke 76. The purpose of the
program was to obtain densely sampled measurements of temperature,
salinity, dissolved oxygen, and chemical nutrients in
the Polar Front Zone (PFZ) and pilot measurements of horizontal
and vertical velocities in order to explain the above scalar
variability. The PFZ is a region where Antarctic and sub-Antarctic waters intermingle and presumably mix to affect the
properties of Antarctic Intermediate Water. A report on the
third leg of Cruise 107 of the R. V. THOMPSON is presented as
well as a description of the measurements and a preliminary
report of the data. A feature of interest is the pinching off
of a northward meander of the circumpolar current system into
a cyclonic ring of Antarctic Waters.Prepared for the National Science Foundation, Office
for the International Decade of Ocean Exploration,
under Grant OCE75-14056 and the International Southern
Ocean Studies (ISOS) Program
A Measurement of Coherent Neutral Pion Production in Neutrino Neutral Current Interactions in NOMAD
We present a study of exclusive neutral pion production in neutrino-nucleus
Neutral Current interactions using data from the NOMAD experiment at the CERN
SPS. The data correspond to muon-neutrino Charged Current
interactions in the energy range GeV. Neutrino
events with only one visible in the final state are expected to result
from two Neutral Current processes: coherent production, {\boldmath
} and single production in
neutrino-nucleon scattering. The signature of coherent production is an
emergent almost collinear with the incident neutrino while 's
produced in neutrino-nucleon deep inelastic scattering have larger transverse
momenta. In this analysis all relevant backgrounds to the coherent
production signal are measured using data themselves. Having determined the
backgrounds, and using the Rein-Sehgal model for the coherent
production to compute the detection efficiency, we obtain {\boldmath } corrected coherent- events with GeV. We measure {\boldmath }.
This is the most precise measurement of the coherent production to
date.Comment: 23 pages, 9 figures, accepted for publication in Phys. Lett.
Comparison of intra-articular injections of Hyaluronic Acid and Corticosteroid in the treatment of Osteoarthritis of the hip in comparison with intra-articular injections of Bupivacaine. Design of a prospective, randomized, controlled study with blinding of the patients and outcome assessors
<p>Abstract</p> <p>Background</p> <p>Although intra-articular hyaluronic acid is well established as a treatment for osteoarthritis of the knee, its use in hip osteoarthritis is not based on large randomized controlled trials. There is a need for more rigorously designed studies on hip osteoarthritis treatment as this subject is still very much under debate.</p> <p>Methods/Design</p> <p>Randomized, controlled trial with a three-armed, parallel-group design. Approximately 315 patients complying with the inclusion and exclusion criteria will be randomized into one of the following treatment groups: infiltration of the hip joint with hyaluronic acid, with a corticosteroid or with 0.125% bupivacaine.</p> <p>The following outcome measure instruments will be assessed at baseline, i.e. before the intra-articular injection of one of the study products, and then again at six weeks, 3 and 6 months after the initial injection: Pain (100 mm VAS), Harris Hip Score and HOOS, patient assessment of their clinical status (worse, stable or better then at the time of enrollment) and intake of pain rescue medication (number per week). In addition patients will be asked if they have complications/adverse events. The six-month follow-up period for all patients will begin on the date the first injection is administered.</p> <p>Discussion</p> <p>This randomized, controlled, three-arm study will hopefully provide robust information on two of the intra-articular treatments used in hip osteoarthritis, in comparison to bupivacaine.</p> <p>Trial registration</p> <p>NCT01079455</p
Suitability Of Nitisinone In Alkaptonuria 1 (SONIA 1): an international, multicentre, randomised, open-label, no-treatment controlled, parallel-group, dose-response study to investigate the effect of once daily nitisinone on 24-h urinary homogentisic acid excretion in patients with alkaptonuria after 4 weeks of treatment.
BACKGROUND: Alkaptonuria (AKU) is a serious genetic disease characterised by premature spondyloarthropathy. Homogentisate-lowering therapy is being investigated for AKU. Nitisinone decreases homogentisic acid (HGA) in AKU but the dose-response relationship has not been previously studied. METHODS: Suitability Of Nitisinone In Alkaptonuria 1 (SONIA 1) was an international, multicentre, randomised, open-label, no-treatment controlled, parallel-group, dose-response study. The primary objective was to investigate the effect of different doses of nitisinone once daily on 24-h urinary HGA excretion (u-HGA24) in patients with AKU after 4 weeks of treatment. Forty patients were randomised into five groups of eight patients each, with groups receiving no treatment or 1 mg, 2 mg, 4 mg and 8 mg of nitisinone. FINDINGS: A clear dose-response relationship was observed between nitisinone and the urinary excretion of HGA. At 4 weeks, the adjusted geometric mean u-HGA24 was 31.53 mmol, 3.26 mmol, 1.44 mmol, 0.57 mmol and 0.15 mmol for the no treatment or 1 mg, 2 mg, 4 mg and 8 mg doses, respectively. For the most efficacious dose, 8 mg daily, this corresponds to a mean reduction of u-HGA24 of 98.8% compared with baseline. An increase in tyrosine levels was seen at all doses but the dose-response relationship was less clear than the effect on HGA. Despite tyrosinaemia, there were no safety concerns and no serious adverse events were reported over the 4 weeks of nitisinone therapy. CONCLUSIONS: In this study in patients with AKU, nitisinone therapy decreased urinary HGA excretion to low levels in a dose-dependent manner and was well tolerated within the studied dose range. TRIAL REGISTRATION NUMBER: EudraCT number: 2012-005340-24. Registered at ClinicalTrials.gov: NCTO1828463
A Search for Single Photon Events in Neutrino Interactions
We present a search for neutrino-induced events containing a single,
exclusive photon using data from the NOMAD experiment at the CERN SPS where the
average energy of the neutrino flux is GeV. The search is motivated
by an excess of electron-like events in the 200--475 MeV energy region as
reported by the MiniBOONE experiment. In NOMAD, photons are identified via
their conversion to in an active target embedded in a magnetic field.
The background to the single photon signal is dominated by the asymmetric decay
of neutral pions produced either in a coherent neutrino-nucleus interaction, or
in a neutrino-nucleon neutral current deep inelastic scattering, or in an
interaction occurring outside the fiducial volume. All three backgrounds are
determined {\it in situ} using control data samples prior to opening the
`signal-box'. In the signal region, we observe {\bf 155} events with a
predicted background of {\bf 129.2 8.5 3.3}. We interpret this as
null evidence for excess of single photon events, and set a limit. Assuming
that the hypothetical single photon has a momentum distribution similar to that
of a photon from the coherent decay, the measurement yields an upper
limit on single photon events, {\boldmath } per \nm\
charged current event. Narrowing the search to events where the photon is
approximately collinear with the incident neutrino, we observe {\bf 78} events
with a predicted background of {\bf 76.6 4.9 1.9} yielding a more
stringent upper limit, {\boldmath } per \nm\ charged
current event
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