900 research outputs found
Maximum-likelihood retrieval of volcanic ash concentration and particle size from ground-based scanning lidar
An inversion methodology, named maximum-likelihood (ML) volcanic ash light detection and ranging (Lidar) retrieval (VALR-ML), has been developed and applied to estimate volcanic ash particle size and ash mass concentration within volcanic plumes. Both estimations are based on the ML approach, trained by a polarimetric backscattering forward model coupled with a Monte Carlo ash microphysical model. The VALR-ML approach is applied to Lidar backscattering and depolarization profiles, measured at visible wavelength during two eruptions of Mt. Etna, Catania, Italy, in 2010 and 2011. The results are compared with those of ash products derived from other parametric retrieval algorithms. A detailed comparison among these different retrieval techniques highlights the potential of VALR-ML to determine, on the basis of a physically consistent approach, the ash cloud area that must be interdicted to flight operations. Moreover, the results confirm the usefulness of operating scanning Lidars near active volcanic vents
Cognitive Impairment and Age-Related Vision Disorders: Their Possible Relationship and the Evaluation of the Use of Aspirin and Statins in a 65 Years-and-Over Sardinian Population
Neurological disorders (Alzheimer’s disease, vascular and mixed dementia) and visual loss (cataract, age-related macular degeneration, glaucoma, and diabetic retinopathy) are among the most common conditions that afflict people of at least 65 years of age. An increasing body of evidence is emerging, which demonstrates that memory and vision impairment are closely, significantly, and positively linked and that statins and aspirin may lessen the risk of developing age-related visual and neurological problems. However, clinical studies have produced contradictory results. Thus, the intent of the present study was to reliably establish whether a relationship exist between various types of dementia and age-related vision disorders, and to establish whether statins and aspirin may or may not have beneficial effects on these two types of disorders. We found that participants with dementia and/or vision problems were more likely to be depressed and displayed worse functional ability in basic and instrumental activities of daily living than controls. Mini mental state examination scores were significantly lower in patients with vision disorders compared to subjects without vision disorders. A closer association with macular degeneration was found in subjects with Alzheimer’s disease than in subjects without dementia or with vascular dementia, mixed dementia, or other types of age-related vision disorders. When we considered the associations between different types of dementia and vision disorders and the use of statins and aspirin, we found a significant positive association between Alzheimer’s disease and statins on their own or in combination with aspirin, indicating that these two drugs do not appear to reduce the risk of Alzheimer’s disease or improve its clinical evolution and may, on the contrary, favor its development. No significant association in statin use alone, aspirin use alone, or the combination of these was found in subjects without vision disorders but with dementia, and, similarly, none in subjects with vision disorders but without dementia. Overall, these results confirm the general impression so far; namely, that macular degeneration may contribute to cognitive disorders (Alzheimer’s disease in particular). In addition, they also suggest that, while statin and aspirin use may undoubtedly have some protective effects, they do not appear to be magic pills against the development of cognitive impairment or vision disorders in the elderly
Development and validation of a nomogram predicting recurrence risk in women with symptomatic urinary tract infection
Objectives: To develop and externally validate a novel nomogram predicting recurrence
risk probability at 12 months in women after an episode of urinary tract infection.
Methods: The study included 768women from Santa Maria Annunziata Hospital, Florence,
Italy, affected by urinary tract infections from January 2005 to December 2009. Another 373
women with the same criteria enrolled at Santa Chiara Hospital, Trento, Italy, from January
2010 to June 2012 were used to externally validate and calibrate the nomogram. Univariate
and multivariate Cox regression models tested the relationship between urinary tract infection
recurrence risk, and patient clinical and laboratory characteristics. The nomogram was
evaluated by calculating concordance probabilities, as well as testing calibration of predicted
urinary tract infection recurrence with observed urinary tract infections. Nomogram variables
included: number of partners, bowel function, type of pathogens isolated (Grampositive/
negative), hormonal status, number of previous urinary tract infection recurrences
and previous treatment of asymptomatic bacteriuria.
Results: Of the original development data, 261 out of 768 women presented at least one
episode of recurrence of urinary tract infection (33.9%). The nomogram had a concordance
index of 0.85. The nomogram predictions were well calibrated. This model showed high
discrimination accuracy and favorable calibration characteristics. In the validation group (373
women), the overall c-index was 0.83 (P = 0.003, 95% confidence interval 0.51–0.99), whereas
the area under the receiver operating characteristic curve was 0.85 (95% confidence interval
0.79–0.91).
Conclusions: The present nomogram accurately predicts the recurrence risk of urinary
tract infection at 12 months, and can assist in identifying women at high risk of symptomatic
recurrence that can be suitable candidates for a prophylactic strategy
Laparoscopic Excision of Endometriosis May Require Unilateral Parametrectomy
Nerve-sparing complete excision of endometriosis may not be possible. In these patients, unilateral parametrectomy may be a reasonable alternative management strategy
Examples of multi-sensor determination of eruptive source parameters of explosive events at mount etna
International audienceMulti-sensor strategies are key to the real-time determination of eruptive source parameters (ESPs) of explosive eruptions necessary to forecast accurately both tephra dispersal and deposition. To explore the capacity of these strategies in various eruptive conditions, we analyze data acquiredby two Doppler radars, ground- and satellite-based infrared sensors, one infrasound array, visible video-monitoring cameras as well as data from tephra-fallout deposits associated with a weak and a strong paroxysmal event at Mount Etna (Italy). We find that the different sensors provide complementary observations that should be critically analyzed and combined to provide comprehensive estimates of ESPs. First, all measurements of plume height agree during the strong paroxysmal activity considered, whereas some discrepancies are found for the weak paroxysm due to rapid plume and cloud dilution. Second, the event duration, key to convert the total erupted mass (TEM) in the mass eruption rate (MER) and vice versa, varies depending on the sensor used, providing information on different phases of the paroxysm (i.e., unsteady lava fountaining, lava fountain-fed tephra plume, waning phase associated with plume and cloud expansion in the atmosphere). As a result, TEM and MER derived from different sensors also correspond to the different phases of the paroxysms. Finally, satellite retrievals for grain-size can be combined with radar data to provide a first approximation of total grain-size distribution (TGSD) in near real-time. Such a TGSD shows a promising agreement with the TGSD derived from the combination of satellite data and whole deposit grain-size distribution (WDGSD)
Effects of combination of sibutramine and L-carnitine compared with sibutramine monotherapy on inflammatory parameters in diabetic patients
The aim of the study was to evaluate the effects of 12-month treatment with sibutramine plus L-carnitine compared with sibutramine alone on body weight, glycemic control, insulin resistance, and inflammatory state in type 2 diabetes mellitus patients. Two hundred fifty-four patients with uncontrolled type 2 diabetes mellitus (glycated hemoglobin [HbA(1c)] >8.0\%) in therapy with different oral hypoglycemic agents or insulin were enrolled in this study and randomized to take sibutramine 10 mg plus L-carnitine 2 g or sibutramine 10 mg in monotherapy. We evaluated at baseline and after 3, 6, 9, and 12 months these parameters: body weight, body mass index, HbA(1c), fasting plasma glucose, postprandial plasma glucose, fasting plasma insulin, homeostasis model assessment of insulin resistance index, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, leptin, tumor necrosis factor-α, adiponectin, vaspin, and high-sensitivity C-reactive protein. Sibutramine plus L-carnitine gave a faster improvement of fasting plasma glucose, postprandial plasma glucose, lipid profile, leptin, tumor necrosis factor-α, and high-sensitivity C-reactive protein compared with sibutramine alone. Furthermore, there was a better improvement of body weight, HbA(1c), fasting plasma insulin, homeostasis model assessment of insulin resistance index, vaspin, and adiponectin with sibutramine plus L-carnitine compared with sibutramine alone. Sibutramine plus L-carnitine gave a better and faster improvement of all the analyzed parameters compared with sibutramine alone without giving any severe adverse effect
Multi-stakeholder development of a serious game to explore the water-energy-food-land-climate nexus: The SIM4NEXUS approach
This is the final version of the article. Available from the publisher via the DOI in this record.Water, energy, food, land and climate form a tightly-connected nexus in which actions on one sector impact other sectors, creating feedbacks and unanticipated consequences. This is especially because at present, much scientific research and many policies are constrained to single discipline/sector silos that are often not interacting (e.g., water-related research/policy). However, experimenting with the interaction and determining how a change in one sector could impact another may require unreasonable time frames, be very difficult in practice and may be potentially dangerous, triggering any one of a number of unanticipated side-effects. Current modelling often neglects knowledge from practice. Therefore, a safe environment is required to test the potential cross-sectoral implications of policy decisions in one sector on other sectors. Serious games offer such an environment by creating realistic 'simulations', where long-term impacts of policies may be tested and rated. This paper describes how the ongoing (2016-2020) Horizon2020 project SIM4NEXUS will develop serious games investigating potential plausible cross-nexus implications and synergies due to policy interventions for 12 multi-scale case studies ranging from regional to global. What sets these games apart is that stakeholders and partners are involved in all aspects of the modelling definition and process, from case study conceptualisation, quantitative model development including the implementation and validation of each serious game. Learning from playing a serious game is justified by adopting a proof-of-concept for a specific regional case study in Sardinia (Italy). The value of multi-stakeholder involvement is demonstrated, and critical lessons learned for serious game development in general are presented.The work described in this paper has been conducted within the project SIM4NEXUS.
This project has received funding from the European Union’s Horizon 2020 research and innovation programme
under Grant Agreement No. 689150 SIM4NEXUS
Operational resilience of reservoirs to climate change, agricultural demand, and tourism: A case study from Sardinia
Copyright © 2015 Elsevier. NOTICE: this is the author’s version of a work that was accepted for publication in Science of the Total Environment. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Science of the Total Environment (2015), DOI: 10.1016/j.scitotenv.2015.04.066Many (semi-) arid locations globally, and particularly islands, rely heavily on reservoirs for water supply. Some reservoirs are particularly vulnerable to climate and development changes (e.g. population change, tourist growth, hydropower demands). Irregularities and uncertainties in the fluvial regime associated with climate change and the continuous increase in water demand by different sectors will add new challenges to the management and to the resilience of these reservoirs. The resilience of vulnerable reservoirs must be studied in detail to prepare for and mitigate potential impacts of these changes. In this paper, a reservoir balance model is developed and presented for the Pedra e' Othoni reservoir in Sardinia, Italy, to assess resilience to climate and development changes. The model was first calibrated and validated, then forced with extensive ensemble climate data for representative concentration pathways (RCPs) 4.5 and 8.5, agricultural data, and with four socio-economic development scenarios. Future projections show a reduction in annual reservoir inflow and an increase in demand, mainly in the agricultural sector. Under no scenario is reservoir resilience significantly affected, the reservoir always achieves refill. However, this occurs at the partial expenses of hydropower production with implications for the production of renewable energy. There is also the possibility of conflict between the agricultural sector and hydropower sector for diminishing water supply. Pedra e' Othoni reservoir shows good resilience to future change mostly because of the disproportionately large basin feeding it. However this is not the case of other Sardinian reservoirs and hence a detailed resilience assessment of all reservoirs is needed, where development plans should carefully account for the trade-offs and potential conflicts among sectors. For Sardinia, the option of physical connection between reservoirs is available, as are alternative water supply measures. Those reservoirs at risk to future change should be identified, and mitigating measures investigated.European Commission Seventh Framework Project ‘WASSERMed’ (Water Availability and Security in Southern EuRope and the Mediterranean
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