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In this work, we propose a methodology to approach the design of chemical absorption columns with fast gas-liquid reactions by an experimental and modelling study, which accounts for thermodynamic (solubility) data, mass-transfer phenomena, and the reaction kinetics contribution. As a reference case, the SO2 absorption in aqueous solution of H2O2 at different concentrations, which oxidizes SO2 to sulfuric acid, is considered. A lab-scale fed-batch bubble column is used to evaluate SO2 solubility dataset in absorbing solutions of distilled water containing different dosages of H2O2. A thermodynamic model is developed and validated in a Thermodynamic Flash block of ASPEN PLUS®, allowing to describe the experimental results with optimum agreement. For kinetic experiments, a lab-scale falling-film absorber is used to investigate both SO2 mass-transfer rates and the fundamental kinetic aspects of an absorption process with chemical reaction. The physical contribution to the mass-transfer rate is evaluated through a set of dedicated experiments, which allowed determining gas-side (kGa) and liquid-side (kLa) coefficients in the falling-film absorber. Subsequently, the Enhancement factor (EL) of the SO2 oxidative absorption is evaluated for the oxidizing reaction (SO2 + H2O2 → H2SO4) under the explored experimental conditions, using the equilibrium dataset and the mass transfer coefficients previously obtained. Finally, EL is correlated to the Hatta number (Ha) with the Danckwerts kinetic model as a pseudo-mth-nth-order non-reversible reaction type and the model kinetic parameters are calculated.

Background: Irritable bowel syndrome (IBS) is a functional bowel disorder characterized by abdominal pain or discomfort and an irregular bowel habit. The prevalence is up to 20% in Western adults, which makes IBS the most common diagnosis in gastroenterology. Despite extensive interest and investigation, IBS's precise aetiology and pathophysiology are poorly understood. Current knowledge suggests that an altered gut microbiota, altered motility, visceral hyperalgesia, and dysregulation of the brain-gut axis are central to IBS. This is also significantly related to a higher prevalence of metabolic syndrome and elevated triglycerides among the adult population. This retrospective study examines the effect of a novel nutraceutical compound, Triobiotix, on gastrointestinal symptoms in IBS patients. Effects on lipid profiles have also been recorded. Objectives: The focus of this study is to evaluate the effectiveness of Triobiotix, a nutraceutical compound composed of prebiotics and probiotics. Methods:Triobiotix is a nutraceutical consisting of Maltodextrin; mineralized extract of Lithothamnion (Lithothamnion calcareum (Pallas) Areschoug, thallus dry extract); Bioecolians® gluco-oligosaccharides; Ferment mix (corn starch, Bifidobacterium animalis ssp. Lactis BLC1 (DSM 17741), Lactobacillus acidophilus LA3 (DSM 17742), Lactobacillus rhamnosus IMC 501 (DSM 16104), Lactobacillus paracasei Streptococcus 501 IMC102 SP4 (DSM 19385); short-chain fructo-oligosaccharides powder. The database of 40 Italian General Practitioners (GPs) was analyzed. A total of 587 patients with IBS treated with Triobiotix were identified. Among them, 535/587 (91.1%) completed the first (T0) and second (T1) visits and their data were available. The primary endpoint of this analysis was to assess if Triobiotix, at a dosage of 1 sachet per day for 30 days, could reduce abdominal pain and bloating, thus resulting in a lower intensity of the main gastrointestinal symptoms. Secondary endpoints were to evaluate presence of any significant changes in triglycerides blood levels and glycaemia.Results: Treatment with this nutraceutical for one month resulted in a reduction in the frequency and intensity of bloating, abdominal pain, flatulence, and tenesmus. In the 85 patients who reported evacuative urgency, the frequency of the episodes didn’t significantly change while their intensity was statistically reduced. Unexpectedly, triglyceride levels also significantly decreased.Conclusions:Our analysis demonstrates this formulation is effective in the relief of the main symptoms associated with IBS. Moreover, an unexpected effect of this combination of micronutrients on tryglicerides, beyond IBS symptoms, was also found. However, further studies are needed to confirm this evidence and to evaluate the particular compound responsible of this effect.Keywords: Irritable bowel disease; Triglyceridemia; Nutraceuticals

Spent automotive catalysts are industrial non-hazardous wastes of high added values because of the presence of platinum group metals, whose recovery is gaining increasing attention in European countries. This paper proposes a hydrometallurgical process to recover platinum from diesel catalysts, based on a first leaching step with aqueous solutions of H2O2 (up to 0.2 M) and mild HCl concentrations (0.4 M), followed by a refining step in which platinum is deposited over a granular activated carbon. Tests were carried out at different H2O2 content, temperatures, and sizes of granulated catalyst. The use of H2O2 and low HCl content allows higher sustainability than conventional hydrometallurgical processes by reducing safety risks associated with the use of concentrated HCl and the emissions of NOx deriving from the use of nitrogen species in conventional leaching. Besides, the use of an adsorbent avoids the utilization of cyanides or other toxic organic solvents for the refining of the leaching solution. Experiments revealed that the low HCl concentration results in longer leaching times; however, process conditions can be tuned to completely recover platinum with negligible extraction of other metals on the catalyst, minimizing on the subsequent adsorption process. Optimal conditions appear as leaching at 20 °C with a 0.13 M H2O2 0.4 M HCl solution followed by an adsorption step at 20 °C using an activated carbon with high BET surface area and high content of reducing surface groups. These findings suggest that the proposed recovery process can be a suitable candidate for future technology implementations.

Deadwood plays a key role in the functioning and productivity of forest ecosystem and it is an important feature for assessing and monitoring biodiversity. The third Ministerial Conference on the Protection of Forests in Europe (MCPFE) has recognized the importance of this forest component at the European level. More recently the national forest inventories have tried to harmonize the procedures including the quantitative and qualitative measurements of deadwood. This paper reports on the methods and results of Italian National Inventory of Forests and Forest Carbon Sinks (INFC) and compares the deadwood data with the results of other main European inventories and some local studies. In Italy the volume of deadwood (logs, snags and stumps) is on average 8.8 m3 ha-1.

Adsorption on activated carbon is one of the most reliable and efficient technologies for the remediation of water polluted by heavy metals. In groundwater remediation, it actually found practical application in both pump-and-treat systems and permeable adsorbing barriers. One of the most significant limits to the practical adsorption of heavy metals in water streams is the absence of experimental data and modeling analysis coupling equilibrium and kinetic properties. In particular, kinetics and equilibrium results of hexavalent chromium adsorption onto activated carbon (AC) are significantly affected by ion speciation, which is made even more complex by the occurrence of reduction reactions on the AC surface. To the best of our knowledge, as at today reliable experimental data describing the mechanisms of chromium adsorption are still lacking as accurate supporting mathematical models for a proper design of industrial adsorbers are. In this work, the results of equilibrium and kinetic tests on the adsorption of chromium on a commercial granular AC are presented. Adsorption isotherms were determined in stirred batch reactors at different levels of pH, temperature and salinity. Kinetic tests were carried out in terms of breakthrough curves of a lab-scale fixed bed column at different levels of pH, inlet concentration and flow rate. Both the adsorption isotherms and the breakthrough curves showed non-linear and unconventional trends as a function of the main process parameters. The experimental results revealed that chromium speciation, in particular Cr(VI) reduction to Cr(III) reactions, played a key role in the adsorption process. Equilibrium tests were interpreted in light of a multi-component Langmuir model supported by the ions speciation analysis. Once the adsorption equilibrium assessed, it was possible to analyze the results of adsorption kinetics, so as to allow determining the mechanism that controls the adsorption rate in the investigated conditions.

In the framework of control methods for adaptive phased-arrays, this paper describes an innovative technique based on a memory enhanced optimization for dealing with complex scenarios and system models. Compared to other existing approaches working with far-field interferences, such a method focus on realistic situations where jamming sources are located both in the near-field or in the far-field of the antenna. Moreover, the effects of the mutual coupling are taken into account. A set of selected numerical results are presented in order to confirm the effectiveness of the proposed technique.

We address the widely open problem of access control in wireless sensor networks (WSN). Namely, we apply a suitable threshold secret sharing scheme relying on advanced polynomial interpolation theory to design a distributed access control protocol exploiting the natural hierarchical structure of the WSN.

A cellular automata model is used to study aspects of cultural change in spatial environments. Culture are represented as bit strings in individual cells. Cultures may change because they become more similar to prevailing nearby cultures, are subject to intrinsic random changes, or expand to previously empty cells. Extending Axelrod's (1997) results, the authors show that assimilation does not lead to a single homogeneous culture even if, unlike Axelrod's model, culturall assimilation may take place even between neighboring cells with zero similarity; intrinsic changes decrease rather than increase the number of stablecultural regions; and expansion of a single culture in a previously unoccupied territory does not result in a single culture in the entire territory. Geographical features (such as mountains) that are an obstacle to contact between cells increase the number of different cultural regions.

Urethral diverticula is a rare pathology with an incidence varying between 0.3 and 6%. It is difficult to diagnose owing to the aspecificity of its clinical symptoms. The aim of this study was to evaluate the imaging techniques now available for its diagnosis.The sample consisted of 19 female patients aged between 20 and 53 years old undergoing diverticolectomy owing to urethral diverticula between 1980 and 1996 at the 4th Division of the Department of Urology at "La Sapienza" University of Rome. All patients underwent preoperative X-ray examinations (micturitional cystourethrography and P positive urethrography). A retrospective study was performed in order to evaluate the accuracy of the individual methods.Micturitional urethrocystography showed a sensitivity equivalent to 77% of cases. P positive urethrography showed a 85.7% accuracy rate. Lastly, transvaginal ultrasonography, which always showed the diverticular sac in all patients in which it was used, also highlighting multiple and divided diverticuli which were not visible using traditional radiology. The latter method is easy to use and well tolerated by patients; moreover, it shows the spatial relations of the diverticulum and allows the characteristics of periurethral tissues to be evaluated.The authors affirm that transvaginal ultrasonography is the first method of choice for the diagnosis of urethral diverticula.

The structure of the wall of the rat seminiferous tubules has been studied by electron microscopy. No significant modifications have been revealed after the ligature of the vas deferens while on the contrary the ligature of the efferent ductules produces a reduction of the contractile filaments and of the pinocytosis vesicles, as well as an increase of the amount of collagen fibers in the basal membrane.

The reported incidence of iatrogenic ureteral injuries ranges from 0.05 to 30%. These injuries are particularly secondary to gynecologic surgical procedures. Simple abdominal hysterectomy has proved to be the most common procedure leading to such injures. Because some ureteral injuries may be symptomless, leading to silent kidney loss, the incidence may be too low, and a figure of up to 2.5% after gynecologic operations has been suggested. The incidence continues to be about ten cases during abdominal surgery for one case during vaginal surgery. Different risk factors may influence the ureteral injuries rate. An operation at the pelvic brim, distorted anatomy, removal of the adnexa or of ovarian neoplasm, may facilitate the occurrence of an ureteral trauma. The management of ureteral trauma is positively influenced by an early recognition of the trauma. Conventional technique or ureteroneocystostomy or end to end anastomosis with ureteral stent to treat the injury proved successful. Extensive reconstruction draws upon the entire therapeutic armamentarium of the urologist. Surgical options mainly include creation of bladder tubes and autotransplantation. The most important factor influencing the management of ureteral injury is the presence of associated complications. Blandy et al. sustained to attempt repair of these complicated iatrogenic injuries as soon the diagnosis has been made.

An ultrastructural analysis has been carried out on the seminiferous tubules after different periods of stay of the rat testis in the abdominal cavity. With respect to control rats, no changes are detectable after 5 days, while after 15 and 30 days considerable modifications take place. A number of cellular features are modified, such as the nuclear shape and the perinuclear vesicles, while the cytoplasmic filaments show a less ordered appearance. In addition, the extracellular amorphous matrix undergoes a large increase, due either to an enhanced production or to a reduced turnover related with a lowered cell activity.

The authors present an experimental project that aims to establish an effective navigation system in accordance with European Council Regulation 1/2005 concerning animal welfare during transport. The prototype created during the project consists of both hardware and software components. An onboard unit is installed at truck level. It collects and transmits real-time information of the animal transport to a remote receiver database. A Web/geographic information system (GIS) application is used to analyse and monitor the information received. The architecture of the hardware and software of the project is presented, focusing on the features of the Web-GIS application.

This paper introduces a personalized content preparation and delivery framework for universal multimedia access. This framework has a wealth of potential applications in broadcasting, the World Wide Web and mobile telecommunication. Content preparation deals with the generation of summaries by automatic video analysis techniques, and with the annotation of content using MPEG–7 for search and retrieval and SMIL for interactive video. The use of open standards favors interoperability with third-party applications and upcoming hardware. Content delivery handles individual user preferences, content selection, real-time content adaptation and streaming in a seamless way. The proposed framework has been implemented in the EC–funded R&D project PERSEO and tested by selected groups of end-users. Personalization, video summaries and the overall usability have been positively evaluated.

Studies of the development of sentence comprehension strategies in English have indicated that, at first, children tend to rely on pragmatic and semantic strategies, whereas, later on, they rely primarily on word order to determine the basic grammatical relations. However, before making strong conclusions regarding the role of semantics in comprehension, it is necessary to distinguish between (1) extragrammatical knowledge of world events and (2) abstract semantic distinctions that may be an integral part of the parsing process. An earlier study of American and Italian adults indicated that use of such abstract semantic strategies may be a core strategy for parsing in Italian. In the present study, we compared sentence interpretation in American and Italian children between the ages of 2 and 5. From the earliest stages, children showed sensitivity to the relative information value of the various cues in their native language; Italians relied primarily on semantic cues, whereas American children relied on word order. In general, the data did not support claims regarding the existence of universal hypotheses about language structure. There was also evidence that the failure of these young children to make full use of certain interpretive cues resulted from their inability to appreciate the discourse functions of these cues.