778 research outputs found
Memory beyond memory in heart beating: an efficient way to detect pathological conditions
We study the long-range correlations of heartbeat fluctuations with the
method of diffusion entropy. We show that this method of analysis yields a
scaling parameter that apparently conflicts with the direct evaluation
of the distribution of times of sojourn in states with a given heartbeat
frequency. The strength of the memory responsible for this discrepancy is given
by a parameter , which is derived from real data. The
distribution of patients in the (, )-plane yields a neat
separation of the healthy from the congestive heart failure subjects.Comment: submitted to Physical Review Letters, 5 figure
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Effect of prophylactic timolol 0.1% gel on intraocular pressure after an intravitreal injection of ranibizumab: a randomized study
Purpose: The purpose of this study is to make a prospective evaluation of the effect of timolol 0.1% eye gel on short-term intraocular pressure (IOP) after an intravitreal injection (IVI) of ranibizumab.
Participants and methods: One hundred and fifty eyes of 150 IVI-naĂŻve patients with macular edema caused by various pathological conditions (age-related macular degeneration, central or branch retinal vein occlusion, and diabetic retinopathy) were scheduled to undergo an IVI of ranibizumab (0.5 mg/0.05 cc). The patients were randomly divided into three groups: 50 were not treated with timolol before the IVI (group 1); 50 received an instillation of timolol 0.1% eye gel the evening before the IVI (group 2); and 50 received an instillation of timolol 0.1% eye gel 2 hours before the IVI (group 3). The incidence of clinically significant intraocular hypertensive spikes (>25 mmHg and >40 mmHg) was then assessed.
Results: Our findings showed that mean IOP at baseline was significantly higher than at both 5 and 60 minutes after IVI (P25 mmHg were recorded at either time in 27 patients (54%) in group 1, 23 patients (44%) in group 2, and 24 patients (48%) in group 3. None of the between-group differences were significant. Spikes of >40 mmHg (which were only detected 5 minutes after IVI) were recorded in nine (18%), eight (16%), and one patient (2%) in groups 1, 2, and 3, respectively. The only significant difference was between the control and group 3 (P=0.012).
Conclusion: An increase in IOP after antivascular endothelial growth factor IVI is a frequent complication. The prophylactic use of timolol 0.1% gel effectively reduced the mean IOP when administered 2 hours before IVI and was also effective in preventing dangerous IOP spikes of >40 mmHg. It is therefore recommended before IVIs as a means of preventing emergency procedures and preserving the health of the optic nerve
Power-Law Time Distribution of Large Earthquakes
We study the statistical properties of time distribution of seimicity in
California by means of a new method of analysis, the Diffusion Entropy. We find
that the distribution of time intervals between a large earthquake (the main
shock of a given seismic sequence) and the next one does not obey Poisson
statistics, as assumed by the current models. We prove that this distribution
is an inverse power law with an exponent . We propose the
Long-Range model, reproducing the main properties of the diffusion entropy and
describing the seismic triggering mechanisms induced by large earthquakes.Comment: 4 pages, 3 figures. Revised version accepted for publication. Typos
corrected, more detailed discussion on the method used, refs added. Phys.
Rev. Lett. (2003) in pres
Multiscale integration of satellite, airborne and field data for Mediterranean vegetation studies in the natural area of the Castelporziano Estate (Rome)
new experimental approach to land analysis has recently been developed, based on the integration of information
acquired on different scales; it enables the structure and the functionality of the vegetation in natural ecosystems
to be analysed. This research aims at assessing the potentiality of the experimental approach by the integration
of airborne and satellite remotely sensed data with ground measurements of structural parameters. In July
1999 a joint campaign for the acquisition of airborne (MIVIS, spatial resolution 3 m) and satellite remotely
sensed data (Landsat 5TM, spatial resolution 30 m) and measures taken at ground (PAI), was deployed in the
Presidential Estate at Castelporziano (Rome, Italy). The spectral signatures of the main vegetational types of the
Estate were examined and the PAI were related to NDVI values, calculated by means of satellite and airborne
images. The adopted approach enabled PAI maps to be produced. The linear relation between measured PAI and
estimated PAI showed a higher coefficient of determination when the MIVIS data were used. The sensor high
spectral resolution has moreover allowed to better describe the structural characteristics of the main plant typologies
at Castelporziano Estate
A novel boswellic acids delivery form (Casperome (R)) in the management of musculoskeletal disorders: a review
Standard pharmacological treatment of musculoskeletal conditions is often associated with relevant side effects. Botanical preparations endowed with a good tolerability profile, therefore, could have a role in the management of these disorders. Among different natural products, Boswellia serrata extracts have long been used for the treatment of musculoskeletal disorders, given their marked anti-inflammatory activity and their ability to promote tissue regeneration. However, standard preparations of Boswellia serrata show overall modest pharmacokinetic properties, a limitation which may ultimately lead to reduced efficacy. In an effort to improve the pharmacokinetic properties, Casperome\uae, a lecithin-based formulation of Boswellia serrata extract representing the whole natural bouquet, has been developed. This formulation was effective in the treatment of Achilles tendonitis, epicondylitis, radiculopathies, ankle sprains and sport injuries as shown in several clinical studies, the majority of which with a randomized design and all evaluating a number of well-recognized parameters of efficacy for the therapy of musculoskeletal disorder. All studies were consistent in showing a prompt decrease of pain and improvement of functionality of the affected area after supplementation with Casperome\uae, without any relevant adverse effect. Remarkably, these symptomatic improvements were paralleled by reduced plasmatic levels of inflammatory markers and by a diminished need for rescue analgesics. On these bases, Casperome\uae may have a role in the treatment of musculoskeletal disorders. Clinical studies in other similar conditions (e.g., osteoarthritis) appear warranted to further investigate the efficacy of this botanical product in more specific settings
Multiscale integration of satellite, airborne and field data for Mediterranean vegetation studies in the natural area of the Castelporziano Estate (Rome)
new experimental approach to land analysis has recently been developed, based on the integration of information
acquired on different scales; it enables the structure and the functionality of the vegetation in natural ecosystems
to be analysed. This research aims at assessing the potentiality of the experimental approach by the integration
of airborne and satellite remotely sensed data with ground measurements of structural parameters. In July
1999 a joint campaign for the acquisition of airborne (MIVIS, spatial resolution 3 m) and satellite remotely
sensed data (Landsat 5TM, spatial resolution 30 m) and measures taken at ground (PAI), was deployed in the
Presidential Estate at Castelporziano (Rome, Italy). The spectral signatures of the main vegetational types of the
Estate were examined and the PAI were related to NDVI values, calculated by means of satellite and airborne
images. The adopted approach enabled PAI maps to be produced. The linear relation between measured PAI and
estimated PAI showed a higher coefficient of determination when the MIVIS data were used. The sensor high
spectral resolution has moreover allowed to better describe the structural characteristics of the main plant typologies
at Castelporziano Estate
Primary tumor sidedness and benefit from FOLFOXIRI plus bevacizumab as initial therapy for metastatic colorectal cancer. Retrospective analysis of the TRIBE trial by GONO
Right-sided metastatic colorectal cancer (mCRC) patients have poor prognosis and achieve limited benefit from first-line doublets plus a targeted agent. In this unplanned analysis of the TRIBE study, we investigated the prognostic and predictive impact of primary tumor sidedness in mCRC patients and the differential impact of the intensification of the chemotherapy in subgroups defined according to both primary tumor sidedness and RAS and BRAF mutational status
Atomic nanolithography patterning of submicron features: writing an organic self-assembled monolayer with cold bright Cs atom beams
Cs atom beams, transversely collimated and cooled, passing through material masks in the form of arrays of reactive-ion-etched hollow Si pyramidal tips and optical masks formed by intense standing light waves, write submicron features on self-assembled monolayers (SAMs). Features with widths as narrow as 43 ± 6 nm and spatial resolution limited only by the grain boundaries of the substrate have been realized in SAMs of alkanethiols. The material masks write two-dimensional arrays of submicron holes; the optical masks result in parallel lines spaced by half the optical wavelength. Both types of feature are written to the substrate by exposure of the masked SAM to the Cs flux and a subsequent wet chemical etch. For the arrays of pyramidal tips, acting as passive shadow masks, the resolution and size of the resultant feature depends on the distance of the mask array from the SAM, an effect caused by the residual divergence of the Cs atom beam. The standing wave optical mask acts as an array of microlenses focusing the atom flux onto the substrate. Atom 'pencils' writing on SAMs have the potential to create arbitrary submicron figures in massively parallel arrays. The smallest features and highest resolutions were realized with SAMs grown on smooth, sputtered gold substrates
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