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Methane is a crucial energy carrier with a massive use in all sectors and a well-developed distribution and storage infrastructure. In the framework of the efforts made to address the energy transition, it is of great interest the replacement of fossil methane by its synthetic alternative, the Substitute Natural Gas, coming from renewable sources. The reactants (CO/CO2 and H2) for catalytic methanation can be obtained from different pathways involving renewable sources: they could derive, for example, from biomass-produced syngas or from generated H2, exploiting the surplus of renewable electricity to perform water electrolysis, and CO2, which can be a pure captured stream, thus giving a Carbon Capture and Utilization solution. The studies on catalytic methanation have recently been developed with the concept of sorption-enhanced reaction, using a proper sorbent material to adsorb the water produced by the reactions, in order to enhance the equilibrium conditions even at low pressures. The aim of this work was to analyze the Sorption Enhanced Methanation (SEM) in a Dual Fluidized Bed system at 300°C and 1 atm, by selecting CaO as water sorbent and using as simulator Aspen Plus®V10 software. The process was mainly analyzed under stoichiometric conditions, introducing dimensionless parameters to consider different relative quantities of CO and CO2 fed, and different amounts of CaO compared to the stoichiometric one to capture all the generated H2O. The purity of the methane is a sensitive aspect to assess, given the restrictions for injection in the grid, in particular with regard to the percentage of admissible H2. SEM results on the outlet composition showed that H2 on dry basis was never low enough to be fed directly into the grid. The undesired carbonation of CaO was found to be the main reason for this behavior. This secondary reaction seems to be able, by absorbing CO2, to shift the equilibrium of important involved reactions towards the consumption of the methane itself, and the production of H2. To fulfill the limits for injection, another kind of sorbent, not subject to carbonation and already being studied, may be selected, e.g. a zeolite, acting as molecular sieve and giving water selective adsorption. Another interesting condition to be verified may be to evaluate non-stoichiometric conditions, and in particular when H2 is the limiting reactant.

An experimental setup for magnetic hyperthermia operating in non-adiabatic conditions is described. A thermodynamic model that takes into account the heat exchanged by the sample with the surrounding environment is developed. A suitable calibration procedure is proposed that allows the experimental validation of the model. Specific absorption rate can then be accurately determined just from the measurement of the sample temperature at the equilibrium steady state. The setup and the measurement procedure represent a simplification with respect to other systems requiring calorimeters or crucial corrections for heat flow. Two families of magnetic nanoparticles, one superparamagnetic and one characterised by larger sizes and static hysteresis, have been characterised as a function of field intensity, and specific absorption rate and intrinsic loss power have been obtained.

Objective: To assess the effect of Saturday allied health services on a geriatric evaluation and management ward. Methods: A controlled before‐and‐after trial at two wards. Allied health services were added to usual weekday staffing on Saturdays for 6 months on the experimental ward. Length of stay, functional independence, readmissions, discharge destination and costs were evaluated at pre‐intervention (N = 331) and intervention (N = 462). Results: Relative to the comparison ward, the experimental ward had longer length of stay (mean 7.8 days, 95% CI 4.7‐10.8), fewer readmissions (mean 3.1 days, 95% CI 0.6‐5.7) and no difference in the proportion discharged home. Cost‐effectiveness demonstrated no significant difference in cost ($2639, 95% CI $‐386 to $5647) and functional independence gain (3.6 units, 95% CI 0.8‐6.5) favouring the experimental ward. Conclusion: These findings do not support the provision of additional Saturday allied health services in geriatric evaluation and management to reduce length of stay.

Sepsis is well described in the literature as a leading cause of possibly preventable death in the United States. Analysis of baseline data indicated capacity to reduce mortality, significant variation in clinical practice patterns and opportunities for reducing cost per case. Following an enterprise-wide challenge to save lives, a multidisciplinary, facility-based team was organized to improve sepsis care. Systematic improvements in recognizing sepsis and standardizing care resulted in a dramatic reduction in mortality and a significant reduction in direct variable cost.

The relation of total polyphenol content and dynamical astringency was investigated on infusions of yerba mate (YM) (Ilex paraguariensis St. Hilaire), a mild stimulant beverage habitually consumed in South America. YM is a heterogeneous mixture of leaves and small sticks giving place to the types with sticks (YM-S) and without sticks (YM-L) according to the composition. Phytochemical and sensory analysis on three brands of each YM type were performed in order to know if there are differences between types and among brands of the same type. Total polyphenol content, determined by spectrophotometry in six YM infusions at 5% w/v, showed that chlorogenic acid levels were higher for two brands of the YM-L type. Time–intensity (TI) curves revealed that infusions prepared with YM-S lowered their maximal perceived astringency. Neither the type nor the brand of YM assessed affected temporal parameters of astringency TI curves. PRACTICAL APPLICATIONS Dynamic sensory analysis showed its effectiveness to reflect differences in astringent perception of infusions of yerba mate (Ilex paraguariensis St. Hilaire); the presence of sticks in this commodity lowered maximum intensity of astringency. No significant differences were found between these infusions for the remaining time–intensity parameters evaluated.

Purpose. To determine if the impact of Visual Impairment Instrument (IVI) and Glaucoma Symptom Scale (GSS) are valid instruments to assess participation in daily living and ophthalmic complaints, respectively, in a glaucoma population. Methods. Patients with glaucoma were recruited from private and public clinics and completed the IVI and GSS questionnaires. The two scales were assessed for fit to the Rasch model. Unidimensionality, individual item and person fit to the model, response category performance (how respondents differentiate between the response options), differential item functioning (how subgroups, despite equal levels of the underlying trait, respond differently to an individual item), and targeting of items to patients (good spread of items across the full range of patients’ scores) were assessed. Results. One hundred seventy-five participants (mean age 71 year) were recruited. The majority (65%) had primary open angle glaucoma and good presenting visual acuity 6/9 in the better eye (87%). Only one-third of the participants had severe visual field loss in both eyes. Disordered thresholds were evident across all GSS items, indicating that the categories were difficult to discriminate and required category collapsing (5 to 3 categories). There was no evidence of person and item misfit, differential item functioning, and multidimensionality. However, both scales displayed ineffective person-item targeting as a large number of participants demonstrated little difficulty with the most difficult items. Conclusions. Because of unsatisfactory targeting, The IVI and GSS are suboptimal scales to assess patients with glaucoma but relatively good vision. It is likely that items could be added to optimize the performance of both instruments. There may however be a need to develop a glaucoma-specific instrument to assess Quality of Life in this population. (Optom Vis Sci 2007;84:789–796)

Purpose: The aim was to develop a means of rapidly assessing eye health in a cost- and time-effective way to monitor changes over time. Methods: Key features of the five main eye diseases that cause vision loss in Australia were assessed. Participation was volunteer-based from randomly selected Melbourne suburbs. Recruitment was by mail. Anterior segments and fundi were photographed with a digital non-mydriatic fundus camera. Visual fields were tested with Frequency Doubling Technology. A questionnaire collected information about demographics, general health and lifestyle. Findings from this rapid assessment were compared with those from a population-based study. Results: A total of 1695 people, aged between 70 and 79 years (mean 74), were recruited. The rates and causes of visual impairment were similar between the rapid assessment method and the population-based study. Among the 134 people (8%) with visual impairment at presentation, 98 (73%) had undercorrected refractive error, 17 (13%) had age-related macular degeneration, 11 (8%) had cataract, 2 (2%) had diabetic retinopathy and 2 (2%) had glaucoma. Screening costs per participant were only about AU$145, compared with AU$433 in the Melbourne Visual Impairment Project (VIP). The application of Frequency Doubling Technology as well as the use of a non-mydriatic digital camera for fundus and lens photography resulted in an average examination time of less than half the time needed in the VIP. Data collection took 3 months rather than 4 years in the VIP. Conclusion: The rapid assessment method was efficient in time and cost and produced results comparable to a normal population-based survey. Repeating the study design for a similarly sampled group every 2 years would allow the assessment of changes in the prevalence of undiagnosed eye disease.

Clays have been long taken internally due to their sorption effects and the mechanical shielding developed by sheet morphologies. The purpose of this paper is the modelling of the mentioned traditional application in terms of chemical and mineralogical budget towards the body. Four polymineralic clays potentially suitable for therapeutic use were analysed for their mineralogical and geochemical composition. Quartz is always present, as well as feldspars, whereas carbonates are more variable (from trace levels, to about 40%). The clay mineralogy is characterised by mixed layers illite–smectite, kaolinite and illite. Most chemical elements show little anomalies compared to average shale [Turekian, K.K., Wedephol, K.H., 1961. Distribution of the elements in some major units of the earth's crust. Geological Society of America Bulletin, 72, 175–192], excluding Ca that is enriched according to the carbonate occurrence. Another geochemical feature is the depletion of more electronegative elements, among which very hazardous elements may be found. For the preparation of “argillic water”, the clays were dispersed in water and three suspensions were prepared to test the effect of settling time (5 min, 1 h, and 24 h). After the settling, the supernatant was centrifuged to analyse the solution and the particulate. The grinding of clays (a common practice for industrial uses) sensibly reduce the mineralogical selectivity of settling, nevertheless, quartz and feldspars are depleted during settling and phyllosilicates are enriched or fluctuate when the starting value is high; the carbonate content increases or decrease within a narrow interval. The grinding procedure minimises the different behaviour of clay minerals dispersed in water because the clay assemblage of suspended particulate does not show significant trends; only illite shows a slightly decrease. The solute composition is dominated by Na > Si > Ca > K > Mg. The comparison of the 4 clays indicates that the sample richest in mixed layers shows the highest content of many trace elements in solution. The variations of solution chemistry indicate that the less soluble elements decrease with the time of settling (e.g. Fe, Al, Mn): the elements hosted in organic matter or sulphides and soluble in oxidative media, increase with time (V, Mo, Sb, As). Many other elements are rather constant or at very low concentrations. The occurrence of sorptive minerals tends to hide these trends mainly during the first hour of settling. The chemical input to the body was calculated adding the amount of element in solution to the extractable amount from the digestion of particulates. The latter is based on the simulated digestion of clays taken from the literature. A critical point is the definition of a threshold that discriminates between useful and excessive ingestion of chemical elements. Since no reference models are available, the limit for drinking water was used. Considering that adults drink 2 l of water, the maximum daily dose for water was transformed into the amount of each chemical element considered by the law and compared with the amount available from the preparation of “argillic water”. Based on these results, the settling of clays can be tuned in order to emphasise the desired composition or to minimise side effects.

Purpose: To determine baseline eye care utilization by older Victorians in order to assess change in 2 years after an eye health promotion campaign. Methods: A letter of invitation to participate was sent to all people aged 70–79 years in randomly selected Melbourne postcode areas. A questionnaire was designed to allow gathering of eye health-related information. Eye exams included autorefraction, frequency doubling technology and non-mydriatic fundus photography. Results were compared with the Melbourne Vision Impairment Project . Results: A total of 1695 people with a mean age of 74 years were recruited. The overall proportion with visual impairment was 8% (134/1695), of which 27% (36/134) was due to non-refractive causes. Only 31% (11/36) of visually impaired people knew about low-vision services, of whom 20% (7/36) had used them. Of all people with diabetes, only 52% (96/184) had a dilated eye exam within the recommended 2 years (Melbourne Vision Impairment Project 44%). Conclusions: Compliance rates with recommendations for 2-yearly eye exams for people with diabetes have not improved since the last major eye health study in Victoria 10 years ago. The same is true for the rate of undiagnosed glaucoma, suggesting that messages about eye examinations need to be promoted for older people at high risk of vision loss, for example, those with diabetes and at risk of vision loss from glaucoma.

Free radicals are associated with the appearance of disorders such as tumours, CNS alterations and inflammatory pathologies. Their levels are known to be increased in inflammatory diseases due to the activity of prostaglandins, which are related to protein secretion including enzymes. Peroxidase is an oral enzyme that is implicated in the defence of the oral cavity. In this paper, investigations of the effect and mechanism of the activity of prostaglandin E2 (PGE2) on peroxidase secretion of female rat submandibular glands are reported. Results showed that PGE2 significantly increased the secretion of submandibular peroxidase and that this effect was mediated by an increase of intracellular cAMP and nitric oxide synthase activation. This could imply that prostaglandins play a modulatory role in diseases where free radicals are involved.

Chordoid meningioma (CM) is a meningioma containing regions that are histologically similar to chordoma, with trabeculae of eosinophilic, vacuolated cells in a myxoid background and corresponds to ...

L'articolo mostra la situazione degli studi nietzscheani in Italia e i vantaggi dell'edizione critica "Colli-Montinari" per una corretta lettura di Nietzsche

The applicability of a kinetic model for the prediction of steady-state blood levels, based on body composition as assessed by bioelectric impedance analysis (BIA), was applied to a population of elderly patients, candidates for digoxin therapy. Elderlies, all >70 years of age, underwent standard laboratory and clinical evaluation but no further characterization of liver or renal function. These 72 patients were given 0.125 mg digoxin for 5 days, in order to reach steady-state levels. Treatment was then interrupted and samples were collected 2 and 48 h after the last administration. Plasma digoxin levels were determined both by the immunochemical method with TDX and according to the BIA method described in the accompanying paper. Plasma levels calculated and measured in 2 h samples did not differ statistically, but levels were about 15% higher in the directly measured samples. There was a similar underestimation, i.e. about 15%, for the 48 h calculated levels. However, only approximately 5% of the levels were outside of the 95% confidence intervals as determined from the directly measured levels. These findings indicate that digoxin levels, calculated based on a BIA evaluation, may be sufficiently reliable, in the majority of patients, to allow direct determination of the more appropriate doses of digoxin.

PURPOSE: This study investigated the association between visual field loss and participation in daily activities in individuals with glaucoma. METHODS: Seventy-nine patients were recruited from the Royal Victorian Eye and Ear Hospital. Visual fields were assessed using the Esterman binocular visual field tests and participation in daily activities was assessed using the Impact of Vision Impairment (IVI) questionnaire. Visual acuity and contrast sensitivity were also measured. RESULTS: There was no independent relationship between visual field loss and IVI score (r = -0.20; P = 0.09), except for the mobility domain (r = 0.25; P = 0.03). Mobility was the most affected domain of the IVI (mean = 1.2). Over a quarter of the patients reported experiencing moderate to severe restriction with mobility activities despite relatively minor binocular field loss. CONCLUSION: Mobility is the area in which glaucoma patients encounter difficulties even when the visual field and visual acuity are relatively good. Questions related to mobility could be asked to identify those patients who need rehabilitation.

Background: Chronic hypergastrinaemia causes gastric enterochromaffin cell proliferation and carcinoid tumours. The only reliable means to diagnose enterochromaffin cell changes/carcinoids is by biopsy. Aim: To assess whether serum histamine, chromogranin A or serotonin and urinary N-methylimidazoleacetic acid or 5-hydroxyindoleacetic acid correlate with advanced enterochromaffin cell changes or gastric carcinoids in patients with gastrinomas. Methods: Consecutive patients (n=145) had the above assays and endoscopy with gastric biopsies. Results: Lower N-methylimidazoleacetic acid and chromogranin A levels (P

Elastofibroma dorsi (ED) is considered a member of a heterogeneous group of benign fibrous (fibroblastic or myofibroblastic) soft-tissue tumors, frequently localized in the periscapular region in middle aged or older individuals. However, the pathogenesis of ED is still unclear and many authors believe that ED results from a reactive hyperproliferation of fibroblastic tissue, while others suggest that it may be a consequence of a mechanical friction. In our study, we examined 11 cases of ED using histochemical and immunohistochemical methods, in order to extend the knowledge about extracellular matrix composition and histopathogenesis of ED. From the results it appeared that stroma and interspersed spindle cells of ED were positive for both periostin and tenascin-C. Mast cells tryptase-positive were also abundant throughout the lesion. The perivascular distribution of periostin and tenascin-C, associated with the CD34 positivity, suggest that endothelial-mesenchymal transition events can account for neovascularization and production of fibroelastic tissue characteristic of elastofibroma. Our data obtained in endothelial cells cultures demonstrated that elastin production is higher when the status of confluence of the cells is low. So, we can assume that such a phenomenon is a characteristic of mesenchymal/endothelial cells CD34 positive, in which elastin production results to be inversely proportional to the vascular differentiation of cellular elements. In the light of these considerations, we think that a cancerous nature of ED is unlikely. Overall, our study report, for the first time, a detailed description of extracellular matrix composition in ED, suggesting that a mechanical strain-dependent reactivation of periostin and tenascin-C expression, as well as of elastin deposition, could be responsible for development of ED.

Carcinoid tumors were identified in the antro-pyloric mucosa of four patients with multiple endocrine neoplasia type 1 (MEN-1)/Zollinger-Ellison syndrome, accounting for 8.7% of 46 patients with this condition examined by endoscopy and histology. In contrast, no tumors were found in the antral biopsies from 124 cases of sporadic Zollinger-Ellison syndrome (P < 0.001), indicating a prominent role for the MEN-1 gene defects in tumor development. Immunohistochemically the tumors did not express the hormones produced by antral endocrine cells (gastrin, somatostatin, serotonin). In contrast, two of them were diffusely immunoreactive for the isoform 2 of the vesicular monoamine transporter (VMAT-2), a marker specific for the gastric nonantral enterochromaffin-like (ECL) cells. In one of these patients a second antral VMAT-2-positive carcinoid was seen 21 months after the first diagnosis. The other two antral carcinoids were unreactive for VMAT-2. Multiple ECL cell tumors were found in the gastric body-fundus mucosa of the two patients with VMAT-2-positive, but not in those with VMAT-2-negative, antral carcinoids. In one case, the former tumors were diagnosed 22 months after the detection of the antral tumor. We conclude that the antral mucosa is an additional tissue that may harbor endocrine tumors in MEN-1 syndrome. These tumors did not express the phenotype of normal antral endocrine cells and, in at least two cases, were identified as ectopic ECL cell carcinoids.

Summary In this paper, we report the effect of standard NDGA, as compared to that of an aqueous extract of Larrea divaricata Cav., on BW 5147 lymphoma cell-line proliferation. To determine the mechanism of action, the effects of both on the level of intracellular cAMP, protein kinase C activity and calcium influx were studied. Moreover, the NDGA present in the aqueous extract of the plant was quantified. The aqueous extract and the standard NDGA showed antiproliferative action against these cells. While the antiproliferative activity of the aqueous extract was mediated by an increase in cAMP levels, and inhibition of PKC and calcium influx, the antiproliferative activity of NDGA was related only to the inhibition of PKC. Considering the amount of NDGA detected in the aqueous extract of the plant, at the concentrations analyzed in this case, antiproliferative activity of Larrea divaricata cannot be attributed to this compound, but could have an additive effect on the activity of other compounds.

The channeling radiation is emitted by fast charged particles crossing a crystal target in a direction nearly parallel to the crystal axis or planar directions. The incident particles are trapped in the potential wells due to the crystal lattice, resulting in a coherence effect in the emitted radiation. Since the total energy of the emitted radiation depends on the Lorentz factor as γ 2 , channeling radiation can be applied to discriminate between different particles with the same momentum in a collimated beam. To study this application of the channeling radiation, we have performed a beam test campaign at the CERN PS-T9 and SPS-H4 facilities using a 500 μ m thick 〈 1 1 0 〉 silicon crystal. A NaI calorimeter has been used to detect the channeling gamma-rays produced in the crystal. The electron (positron) pion identification performance has been studied. The preliminary results will be shown and the perspectives will be discussed.

To investigate the optimum number of biopsy specimens to be obtained for enterochromaffin-like (ECL) cell monitoring in hypergastrinemic patients and ECL cell regional variations potentially influencing the results, qualitative ECL cell changes were assessed in 149 patients with Zollinger-Ellison syndrome using jumbo biopsy specimens and a systematic sampling procedure of 4 areas each from the lesser or greater curvature of the gastric body. Of 1,176 specimens examined, 1,101 were adequate. The correlation was excellent between different sites within the greater or lesser curvature. In contrast, a normal ECL cell pattern was more frequent in the lesser curvature, whereas linear hyperplasia was more frequent in the greater curvature. Dysplastic lesions and carcinoid tumors in endoscopically unremarkable mucosa were detected in 3.4% and 1.2% of biopsy specimens, respectively, and were equally distributed between the lesser and greater curvature. Their chances of being diagnosed were related to the number of specimens examined. Extensive sampling of both the lesser and greater curvature is recommended for early diagnosis of dysplastic and/or carcinoid lesions in patients at risk. In contrast, limited sampling in the greater curvature seems to be adequate in patients with no risk for carcinoid development.

This review discusses the current concepts for the classification of gastric endocrine cells subdivided according to the type of mucosa in which they are located. In the oxyntic mucosa, the most important cell type is the ECL cell, involved in the synthesis and secretion of histamine. Proteins involved in many aspects of the biology of ECL cells including the response to the gastrin stimulus, membrane transport and docking, prevention of apoptosis, calcium homeostasis, autocrine activity, and maintenance of the differentiated cell phenotype have been localized to this cell type. Other cells of the oxyntic mucosa include: the D and EC cells producing somatostatin and serotonin, respectively, delivered through long cell processes; the X (or A-like) cells, possibly producing endothelin; and the D(1) and P cells of unknown function and possibly representing morphological variants of other cell types. In the antral mucosa, the three important cell types are represented by: the gastrin-producing G cells; the somatostatin-producing D cells, which are anatomically and functionally associated with G cells; and the serotonin-producing EC cells, which are located at the bottom of antral glands.

The change of estrogen function, represented by amenorrhea or hot flashes, that results from breast cancer treatment may increase the risk of major depressive disorder in those women undergoing treatment for breast cancer. This pilot study describes the course of menopausal symptoms and the incidence of depression in 21 patients who were likely to become acutely estrogen deficient during treatment for breast cancer. These included women who lost menses during chemotherapy, who suddenly stopped estrogen replacement therapy (ERT), or who started tamoxifen. Eight patients (38%) developed major depressive disorder, the majority within 6 months of starting treatment. Twenty patients (95%) had dysphoria and/or insomnia. Fourteen patients (66%) had hot flashes. While this is only pilot data, these data suggest that breast cancer patients whose treatment precipitates menopausal symptoms should be targeted for diagnosis of depression and treated if diagnosed.