594 research outputs found

    Fishery resources and some economic aspects of four fishing villages on Lakes George and Edward in the Queen Elizabeth National Park, Uganda

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    The fishery resources of Lake George and Ugandan waters of Lake Edward are described. The main fish species currently observed in the commercial catches were determined and the reasons of changes in species composition of the catches. that occurred in the recent years, are explained. The fishing activity and some economic and nutritional aspects of four fishing villages, selected among the ten present within the Queen Elizabeth National Park boundaries, are analyzed, In the end some suggestions are given for management of the fishery resources of these lakes

    Don't judge a book by its cover. factitious disorder imposed on children-report on 2 cases

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    Factitious Disorder Imposed on Another (FDIA), also known as Munchausen Syndrome by Proxy (MSbP) is a very serious form of child abuse. The perpetrator, usually the mother, invents symptoms or causes real ones in order to make her child appear sick. Usually this is due to a maladaptive disorder or to an excessive of attention-seeking on her part. We report here two new cases of FDIA. The first one is a 9-year-old boy with a history of convulsive episodes, reduced verbal production, mild psychomotor disorder and urological problems who underwent several invasive procedures and hospitalizations before a diagnosis of FDIA was made. The second is a 12 year-old girl with headache, abdominal pain, lipothymic episodes, seizures and a gait impairment, who was hospitalized in several hospitals before an FDIA was diagnosed

    Lo scavo della Chiesa di Santa Maria Degli Angeli alla Gancia: indicatori archeologici della prima età islamica a Palermo

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    Lo scavo in occasione del restauro della chiesa di Santa Maria degli Angeli alla Gancia a Palermo ha permesso di recuperare alcune stratigrafie affidabili relative alla prima età islamica a Palermo. Lo studio della ceramica ha restituito una serie di indicatori cronologici per il IX-X secolo nonché di proporre nuove cronologie per alcune classi di materiali. Relativamente alla storia della città questo scavo ha aggiunto alcune note importanti che riguardano il porto e la cittadella e mirale la al-Halisah

    Sintering process of amorphous SiO2 nanoparticles investigated by AFM, IR and Raman techniques

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    We report an experimental investigation on the effects of thermal treatments at different temperatures (room— 1270 K) and for different duration (0–75 h) on amorphous silica nanoparticles (fumed silica) in powder tablet form. Three types of fumed silica are considered, comprising nearly spherical particles of 40 nm, 14 nmand 7 nm mean diameter. The experimental techniques used here are Raman and infrared absorption (IR) spectroscopy together with atomic force microscopy (AFM). Raman and IR spectra indicate that the structure of nanometer silica particles is significantly differentwith respect to that of a bulk silica glass. In particular, themain differences regard the positions of the IR band peaked at about 2260 cm−1, the Raman R-band peaked at about 440 cm−1 and the intensity of the D1 and the D2 Raman lines, related to the populations of 4- and 3-membered rings, respectively. Our data also indicate that, under thermal treatments, the structure of fumed silica samples is significantly changed, gradually relaxing towards that pertaining to ordinary bulk silica. These changes are interpreted here on the basis of the morphological information provided by the AFM measurements and assuming a two-shell structure for the fumed silica primary particles

    Mesoporous silica networks with improved diffusion and interference-rejecting properties for electroanalytical sensing

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    Mesoporous silica materials characterized by well-ordered microstructure and size- and shape-controlled pores have attracted much attention in the last years. These systems can be used for the development of functional thin films for advanced applications in catalysis and electrocatalysis, sensors and actuators, separation techniques, micro- and nano-electronic engineering [1-2]. In this work, \u201cinsulating\u201d and mesoporous silica films were prepared by spin coating a home-made silica sol on a cleaned ITO glass support. The mesoporosity was controlled by the use of Polystyrene (PS) latex beads with different dimensions (30-60-100 nm) as template. The number of successive multi-layer depositions was varied (1-2-3-5 layers) and after the template removal, stable, homogeneous and reproducible transparent films were obtained, characterized by an interconnected porous structure. The morphological features and the physicochemical and optical properties of the films and/or sol-precursors were studied by DLS, FE-SEM, AFM, UV-vis transmittance spectroscopy and wettability analyses. Moreover, a deep electrochemical characterization was also performed by Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). In particular, the use of two redox mediator probes [(K4Fe(CN)6) and (Ru(NH3)6Cl3)], presenting opposite charge and different diffusional behaviour, allowed the comprehension of the mass transport and charge transfer phenomena, evidencing the effects of spatial confinement and charge selection. In the case of \u201cinsulating\u201d films prepared without the use of PS latexes, we proved an experimental evidence for theoretical models [3] concerning electroinactive layer-modified electrodes, with a scan-rate-dependent variation of the CV shape due to a progressive increase in the diffusion coefficient inside the insulating layer. A complex balance between diverging effects (higher hydrophilicity and insulating behavior effects of silica) when increasing the numbers of layers was also observed [4]. In the case of mesoporous layers, a better electrochemical response of smaller pores and of thicker layers was found, due to two main cooperative phenomena: i) a diffusion modification from fully planar to radial-convergent at the pore-silica interface due to surface porosity; ii) the presence of pores in a hydrophilic matrix which leads to a capillary pull effects, stronger in the case of smaller hydrophilic pores. The easiness of preparation and the interesting properties of these devices pave the way towards their use in many fields, particularly trace electroanalysis in real matrices. In fact, for example, the porous and properly charged network is able to exclude interfering macromolecules (mucin in our case), preventing electrode biofouling and enhancing the performances of the sensor towards dopamine detection. References [1] M. Ogawa, Chem. Rec. 17 (2017) 217-232. [2] A. Walcarius, Chem. Soc. Rev. 42 (2013) 4098-4140. [3] D. Menshykau, R.G. Compton, Langmuir 25 (2009) 2519\u20132529. [4] V. Pifferi, L. Rimoldi, D. Meroni, F. Segrado, G. Soliveri, S. Ardizzone, L. Falciola, Electrochem. Commun. 81 (2017) 102-105

    A Narrative Review about Prosocial and Antisocial Behavior in Childhood: The Relationship with Shame and Moral Development

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    We conducted a literature review aimed at identifying the origins of shame as well as its effects on moral development, especially in terms of behavioral outcomes, and we reflected on the practical implications of our findings. We explored the role of shame in moral development through cultural differences and parental influences, collecting evidence of psychopathological consequences of primary moral emotion dysregulation. These studies showed a dichotomous feature of shame, as a prosocial behavior enhancer in morally relevant situations and, simultaneously, a risk factor for aggressive and antisocial behaviors on other occasions. Dysregulated shame leads to maladaptive interpersonal behaviors, which could evolve towards psychopathological paths. Therefore, an integrated intervention is recommended in children with emotional/behavioral problems

    PA6 and halloysite nanotubes composites with improved hydrothermal ageing resistance : role of filler physicochemical properties, functionalization and dispersion technique

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    Polyamide 6 (PA6) suffers from fast degradation in humid conditions due to hydrolysis of amide bonds, which limits its durability. The addition of nanotubular fillers represents a viable strategy for overcoming this issue, although the additive/polymer interface at high filler content can become privileged site for moisture accumulation. As a cost-effective and versatile material, halloysite nanotubes (HNT) were investigated to prepare PA6 nanocomposites with very low loadings (1-45% w/w). The roles of the physicochemical properties of two differently sourced HNT, of filler functionalization with (3-aminopropyl)triethoxysilane and of dispersion techniques (in situ polymerization vs. melt blending) were investigated. The aspect ratio (5 vs. 15) and surface charge (-31 vs.-59 mV) of the two HNT proved crucial in determining their distribution within the polymer matrix. In situ polymerization of functionalized HNT leads to enclosed and well-penetrated filler within the polymer matrix. PA6 nanocomposites crystal growth and nucleation type were studied according to Avrami theory, as well as the formation of different crystalline structures (\u3b1 and \u3b3 forms). After 1680 h of ageing, functionalized HNT reduced the diffusion of water into polymer, lowering water uptake after 600 h up to 90%, increasing the materials durability also regarding molecular weights and rheological behavior

    Conductive inks based on methacrylate end-capped poly(3,4-ethylenedioxythiophene) for printed, flexible and wearable electronics

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    A new synthesis of methacrylate end-capped Poly(3,4-ethylenedioxythiophene) (PEDOT) was performed: the new material obtained is soluble in common organic solvents, thus overcoming the well-known technical problems related to the use of commercial PEDOT in different printing technologies, such as screen printing, due to its poor processability and compatibility in formulations with other resins and polymers [1]. The new synthetic method developed is based on the direct oxidative polycondensation of 3,4-ethylenedioxythiophene (EDOT) in the presence of an oxidant species and a cross-linkable end-capper, i.e. methacrylate end-capped EDOT (mEDOT), prepared via Friedel Crafts acylation with methacryloyl chloride. The oxidative polycondensation between EDOT and mEDOT monomers in the presence of a new kind of doping agent, Sulfonated Polyarylethersulfone (SPAES) [2, 3] - characterized by different degree of sulfonation (DS) - was conducted, leading to functional end-capped conducting PEDOT, with conductivity of 210 S/cm, 50 S/cm higher than the one of commercial PEDOT [6]. Thanks to the enhancement of solubility, leading to better processability, end-capped PEDOTs were formulated with a thermoplastic ink, Plastisol\uae, and electronic circuits were successfully screen printed on flexible textile substrates [4, 5], in order to obtain wearable electronic circuits [7] (Figure 1)

    Pharmacologic P2X purinergic receptor antagonism in the treatment of collagen-induced arthritis

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    OBJECTIVE.: The aim of the present study was to assess the therapeutic potential of a P2X purinergic receptor antagonist, namely periodate oxidized ATP (oATP), in collagen-induced arthritis (CIA). METHODS.: Arthritis was induced in male DBA/1J mice by immunization with type II collagen. Animals showing digits inflammation and paw swelling were treated intraperitoneally each day for 10 days with 100 \u3bcl of 3 mM oATP. At the end of treatment animals were sacrificed and paws removed for histological analysis and evaluation of T-cell infiltration. Humoral response to type II collagen was analyzed and specific serum autoantibody levels were correlated to the clinical score observed in the different animal groups. RESULTS: oATP treatment resulted in a sustained reduction of disease activity, which was associated with a significant decrease in CD3+ T-cells infiltration in arthritic lesions and a significant amelioration of cartilage erosion. Peripheral regulatory T cells (Tregs) were significantly increased upon P2X blockade in lymph nodes. Moreover, a marked reduction of circulating autoantibodies directed against mouse collagen type II wasdetected. CONCLUSIONS.: Our findings indicate that P2X receptor antagonism has an important therapeutic potential for chronic inflammatory rheumatic disorders. The therapeutic efficacy was associated with an increase of Tregs in secondary lymphoid organs. Notably, we observed a significant correlation between serum autoantibodies and clinical efficacy exerted by oATP treatment. Together these results underscore the potential value of the P2X receptor signaling pathway as a potential pharmacological target for the modulation of adaptive immunity in CIA
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