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1.

Background  

The exact cause of schizophrenia is not known, although several aetiological theories have been proposed for the disease, including developmental or neurodegenerative processes, neurotransmitter abnormalities, viral infection and immune dysfunction or autoimmune mechanisms. Growing evidence suggests that specific cytokines and chemokines play a role in signalling the brain to produce neurochemical, neuroendocrine, neuroimmune and behavioural changes. A relationship between inflammation and schizophrenia was supported by abnormal cytokines production, abnormal concentrations of cytokines and cytokine receptors in the blood and cerebrospinal fluid in schizophrenia. Since the neuropathology of schizophrenia has recently been reported to be closely associated with microglial activation we aimed to determined whether spontaneous or LPS-induced peripheral blood mononuclear cell chemokines and cytokines production is dysregulated in schizophrenic patients compared to healthy subjects. We enrolled 51 untreated first-episode schizophrenics (SC) and 40 healthy subjects (HC) and the levels of MCP-1, MIP-1α, IL-8, IL-18, IFN-γ and RANTES were determined by Elisa method in cell-free supernatants of PBMC cultures.  相似文献   
2.
Aeolian mineral dust archived in polar and mid latitude ice cores represents a precious proxy for assessing environmental and climatic variations at different timescales. In this respect, the identification of dust mineralogy plays a key role. In this work we performed the first preliminary X-ray absorption spectroscopy (XAS) experiments on mineral dust particles extracted from Antarctic and from Alpine firn cores using grazing incidence geometry at the Fe K-edge. A dedicated high vacuum experimental chamber was set up for normal-incidence and total-reflection X-Ray Fluorescence and Absorption Spectroscopy analyses on minor amounts of mineral materials at the Stanford Synchrotron Radiation Laboratory. Results show that this experimental technique and protocol allows recognizing iron inclusion mineral fraction on insoluble dust in the 1–10 µg range.  相似文献   
3.
Summary The paper discusses the collapse theorems for materials which do not exhibit normality of the strain rate vector to the yield surface in the superposed stress and strain rate spaces. The consequences of the lack of normality on the designs for minimum weight are considered.
Sommario Si presentano i teoremi fondamentali dell'analisi limite con riferimento a materiali per i quali i vettorï velocità di deformazione plastica non sono normali alla superficie rappresentativa, nello spazio delle tensioni, della condizione di plasticità. Se ne considerano quindi le conseguenze sui progetti di minimo peso.


Study supported by the C.N.R. (Plasticity Group).

We use here the term non-standard materials as currently used in the French literature. English-speaking Authors usually prefer the equivalent expression materials with non-associated flow law.  相似文献   
4.
Summary A generic structure is considered, made up of elements with rigid perfectly plastic standard material and random plasticity constant, however distributed around the average value. The limit load of structures having elements of average plasticity constant is shown to be greater than or equal to the average value of the limit loads of all the feasible structures, thus generalising a theorem [1] formulated for framed structures.The minimum volume of structures having elements of average plasticity constant is then shown to be less than or equal to the average value of the minimum volumes of all the feasible structures. Then the earlier theorems are extended to take in non standard materials.
Sommario Si considera una generica struttura composta da elementi di materiale rigido-plastico standard a costante di plasticità aleatoria e comunque distribuita attorno al valor medio.Si dimostra che il carico di collasso della struttura dotata di elementi a costante di plasticità media è maggiore o uguale al valor medio dei carichi limite di tutte le strutture possibili, generalizzando un teorema [1] formulato per le travature reticolari. Si dimostra poi che il minimo volume della struttura dotata di elementi a costante di plasticità media è minore o uguale al valor medio dei minimi volumi di tutte le strutture possibili. Si estendono quindi i teoremi precedenti al caso di materiali non standard.


This work has been sponsored by C.N.R. (the Italian Council of Research).  相似文献   
5.
In this work, the lightfastness of wool textile samples, dyed with madder and its principal components alizarin and purpurin, was investigated using two complementary experimental techniques: absorption and emission UV-vis spectroscopy and chromatography (HPLC-PDA). Spectroscopic techniques were used to follow the time course of ageing, whereas chromatography was applied to determine relative compositional changes that occurred after exposure of wool dyed samples to natural and artificial ageing. The results from the two techniques integrate well each other and provide complementary and useful indications about the sensitivity of the dyed textiles to ageing, showing that purpurin is the principal component responsible for the spectral and chromatic properties of madder as well as for its degradation. The fading of both the fibre and dye is reduced in the presence of alum and in the absence of oxygen. The multi-analytical approach used highlights the potential of the UV-vis spectroscopy for the investigation of dyes on textiles. The great sensitivity of the spectrofluorimetry makes this technique particularly promising for a non-destructive study of dyes on works of art.  相似文献   
6.
7.
Photodynamic therapy (PDT) is based on the light-induced activation of a photosensitizer generating highly reactive oxygen species that induce tissue destruction in malignant tissues. The present study was carried out to assess the photosensitizing potential of bis(3,5-diiodo-2,4,6-trihydroxyphenyl)squaraine in PDT trials in vivo. Male Swiss albino mice were divided into five groups. Skin tumor was induced using 7,12-dimethylbenz(a)anthracene - DMBA in the animals of Groups II, III, IV and V, while animals of Group I served as the control. At the completion of 20 weeks of induction, the tumor bearing mice from Group III, IV and V were given an intraperitoneal injection with the squaraine dye (12.5mg/kg body weight). After 24h, in the Group IV and V animals, the tumor area was exposed to visible light from a 1000W halogen lamp. The mice from groups I to IV were sacrificed two weeks after the PDT treatment and the marker enzymes (myeloperoxidase [MPO], beta-d-glucuronidase, rhodanese, lactate dehydrogenase [LDH], hexokinase, sialic acid and caspase) were assayed in tumor and normal tissues. Animals from Group V were sacrificed after 90 days of PDT treatment and the above parameters were recorded. Reduction in tumor volume and reversal of biochemical markers to near normal levels were observed in the treatment groups. The study assumes importance as it is the first report on PDT-a novel modality, using a squaraine dye for skin cancer therapy in vivo. The uniqueness of the mode of treatment lies in the selective uptake of squaraine dye by the cancer cells and their selective destruction using PDT without affecting the neighbouring normal cells, which is much advantageous over radiation therapy now frequently used. Also in skin cancer models, the progression/cure can be visualized by the naked eye which is another point of advantage, while seeking new modalities for the treatment of cancer.  相似文献   
8.
In this work the results on X-ray micro-imaging by means of novel polycapillary optical elements will be presented. To simulate various radiation propagation processes in both single capillary and polycapillary systems, a PolyCAD code was developed. The new experimental results on radiation redistribution by novel capillary lenses in comparison with simulated data will be reported. The images of characterized extended samples (~ 3 mm) were recorded with 6 μm resolution, the maximum provided by CCD. Polycapillary Optics CAD software X-ray tracing Imaging Confocal 02.60.Cb 02.70.-c 41.50. + h 42.15.-i 42.15.Dp 42.30.-d.  相似文献   
9.
10.
Basic points of some papers on Optimal Design, published by the authors many years ago, are here presented. This seemed the more suitable choice for recalling the bonds of friendship and academic life that related them for many decades with Giulio Maier. Sommario. Sono richiamati gli aspetti essenziali di alcuni lavori, in tema di ottimizzazione strutturale, pubblicati dagli autori diversi anni orsono. Questa scelta è sembrata la più opportuna per ricordare i legami di amicizia e di vita accademica che da molti decenni intercorrono con Giulio Maier.  相似文献   
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