Human African trypanosomiasis in travellers to Kenya

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The vertical distribution of aerosols, Saharan dust and cirrus clouds at Rome (Italy) in the year 2001

International audienceA set of 813 lidar profiles of tropospheric aerosol and cirrus clouds extinction and depolarization observed at Rome, Italy, between February 2001 and February 2002 is analyzed and discussed. The yearly record reveals a meaningful contribution of both cirrus clouds (38%) and Saharan dust (12%) to the total optical thickness (OT) of 0.26, at 532 nm. Seasonal analysis shows the planetary boundary layer (PBL) aerosols to be confined below 2 km in winter and 3.8 km in summer, with relevant OT shifting from 0.08 to 0.16, respectively. Cirrus clouds maximize in spring and autumn, in both cases with average OT similar to the PBL aerosols one. With the exception of winter months, Saharan dust is found to represent an important third layer mostly residing between PBL aerosols and cirrus clouds, with yearly average OT~0.03. Saharan dust and cirrus clouds were detected in 20% and in 45% of the observational days, respectively. Validation of the lidar OT retrievals against collocated sunphotometer observations show very good agreement. These results represent one of the few yearly records of tropospheric aerosol vertical profiles available in the literature

Aerosol seasonal variability over the Mediterranean region and relative impact of maritime, continental and Saharan dust particles over the basin from MODIS data in the year 2001

International audienceThe one-year (2001) record of aerosol data from the space borne Moderate Resolution Imaging Spectroradiometer (MODIS) is analyzed focusing on the Mediterranean region. The MODIS aerosol optical thickness standard product (AOT at 550nm) provided over both land and ocean is employed to evaluate the seasonal and spatial variability of the atmospheric particulate over the region. Expected accuracy of the MODIS AOT is (±0.05±0.2xAOT) over land and (±0.03±0.05xAOT) over ocean. The seasonal analysis reveals a significant AOT variability all over the region, with minimum values in Winter (AOT0.2). The spatial variability is also found to be considerable, particularly over land. The impact of some major urban sites and industrialized areas is detectable. For the sole Mediterranean basin, a method (aerosol mask) was implemented to separate the contribution of maritime, continental and desert dust aerosol to the total AOT. Input of both continental and desert dust particles is well captured, showing North-to-South and South-to-North AOT gradients, respectively. A quantitative summary of the AOT seasonal and regional variability is given for different sectors of the Mediterranean basin. Results of this summary were also used to test the aerosol mask assumptions and indicate the method adopted to be suitable for the aerosol type selection. Estimates of the atmospheric aerosol mass load were performed employing specifically-derived mass-to-extinction efficiencies (?). For each aerosol type, a reliable mean ? value was determined on the basis of both lidar measurements of extinction and aerosol models. These estimates indicate a total of 43Mtons of desert dust suspended over the basin during 2001. A comparable value is derived for maritime aerosol. Opposite to the dust case, a minor seasonal variability (within 15%) of maritime aerosol mass is found. This latter result is considered a further check of the suitability of the methodology adopted to separate, on the basis of MODIS data, the three aerosol types which dominate the Mediterranean region

General behavioral patterns and life-cycle of the colonial spider, Eriophora bistriata (Araneida: Argiopidae)

Neste estudo, apresentamos observações preliminares do comportamento e biologia da aranha gregária Eriophora bistriata. O trabalho inclui aspectos da organização social, obtidos através de estudos de laboratório e campo. São inicialmente descritos, além do ciclo básico, algumas interações como: construção de teia comum de caça, ausência de hostilidade inter-individual, alimentação comunal, comportamento reprodutor etc. Os resultados obtidos permitiram comparar Eriophora bistriata, com outras espécies gregárias segundo o esquema evolutivo de Shear (1970: pag. 73)

An important fingerprint of wildfires on the European aerosol load

Abstract. Wildland fires represent the major source of fine aerosols, i.e., atmospheric particles with diameters <1 μm. The largest numbers of these fires occur in Africa, Asia and South America, but a not negligible fraction also occurs in Eastern Europe and former USSR countries, particularly in the Russian Federation, Ukraine and Kazakhstan. Besides the impact of large forest fires, recent studies also highlighted the crucial role played by routine agricultural fires in Eastern Europe and Russia on the Arctic atmosphere. An evaluation of the impact of these fires over Europe is currently not available. The assessment of the relative contribution of fires to the European aerosol burden is hampered by the complex mixing of natural and anthropogenic particle types across the continent. In this study we use long term (2002–2007) satellite-based fires and aerosol data coupled to atmospheric trajectory modelling in the attempt to estimate the wildfires contribution to the European aerosol optical thickness (AOT). Based on this dataset, we provide evidence that fires-related aerosols play a major role in shaping the AOT yearly cycle at the continental scale. In general, the regions most impacted by wildfires emissions and/or transport are Eastern and Central Europe as well as Scandinavia. Conversely, a minor impact is found in Western Europe and in the Western Mediterranean. We estimate that in spring 5 to 35% of the European fine fraction AOT (FFAOT) is attributable to wildland fires. The estimated impact maximizes in April (20–35%) in Eastern and Central Europe as well as in Scandinavia and in the Central Mediterranean. An important contribution of wildfires to the FFAOT is also found in summer over most of the continent, particularly in August over Eastern Europe (28%) and the Mediterranean regions, from Turkey (34%) to the Western Mediterranean (25%). Although preliminary, our results suggest that this fires-related, continent-wide haze plays a not negligible role on the European radiation budget, and possibly, on the European air quality, therefore representing a clear target for mitigation

Noise and vibration modelling of Permanent Magnet Synchronous Motors - a review

This paper provides an overview of current Noise Vibration and Harshness (NVH) challenges for the design of Permanent Magnet Synchronous Motors (PMSMs) for automotive applications. Particular attention is devoted to analytical and numerical methods utilized in NVH mod&#x2;elling. Electromagnetic force computation, motor structural modelling and acoustic emission calculation are reviewed focusing on NVH emissions. The literature reveals, as ex&#x2;pected, that analytical methods are simpler than numerical ones, and are usually employed during the preliminary de&#x2;sign stage. Numerical methods are adopted in the detailed design stage as the computational cost increases. PMSMs are selected for high performance and high efficiency motor drives, they are widely adopted in the actual transition to vehicle electrification. The paper provides guidelines for facing NVH design issues of PMSMs

Interplay Between Endocannabinoid System and Neurodegeneration: Focus on Polypharmacology

Pharmacological treatment of complex pathologies, such as neurodegenerative diseases still represents a major challenge, due to the networked pathways involved in their onset and progression that may require equally complex therapeutic approaches. Polypharmacology, based on the simultaneous modulation of multiple targets involved in the disease, may offer the potential to increase effectiveness and reduce the drawbacks related to the use of drug combinations. Clearly, this approach requires both the knowledge of the systems responsible for disease development and the discovery of new attractive targets to be exploited to design a multitarget drug. Over the last years, an ever increasing interest has focused on the endocannabinoid system, implicated in the modulation of several physiological functions, among which neuroinflammation, a crucial process for most neurodegenerative diseases. In this respect, the cannabinoid receptor subtype 2 represents a promising therapeutic target, being overexpressed in microglia cells and thus involved in neuroinflammation. The indirect modulation of this system through the inhibition of the main enzymes responsible for endocannabinoids metabolism, namely fatty acid amide hydrolase and monoacylglycerol lipase, may also significantly affect neurodegenerative processes. The aim of this review is to give an overview of the opportunities posed by the endocannabinoid system for neurodegenerative diseases management, mainly focusing on the potential for a multitarget strategy

Flavonoid-inspired vascular disrupting agents: Exploring flavone-8-acetic acid and derivatives in the new century

Naturally occurring flavonoids are found as secondary metabolites in a wide number of plants exploited for both medicine and food and have long been known to be endowed with multiple biological activities, making them useful tools for the treatment of different pathologies. Due to the versatility of the scaffolds and the vast possibilities of appropriate decoration, they have also been regarded as fruitful sources of lead compounds and excellent chemical platforms for the development of bioactive synthetic compounds. Flavone-8-acetic acid (FAA) and 5,6-dimethylxanthone acetic acid (DMXAA) emerged for their antitumour potential due to the induction of cytokines and consequent rapid haemorrhagic necrosis of murine tumour vasculature, and different series of derivatives have been designed thereafter. Although the promising DMXAA failed in phase III clinical trials because of strict species-specificity, a boost in research came from the recent identification of the stimulator of interferon genes (STING), responsible for supporting tumoural innate immune responses, as a possible biological target. Consequently, in the last decade a renewal of interest for these flavonoid-based structures was noticed, and novel derivatives have been synthesised and evaluated for a deeper understanding of the molecular features needed for affecting human cells. Un-doubtedly, these natural-derived molecules deserve further investigation and still appear attractive in an anticancer perspective