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The principal limiting factor in the clinical acceptance of scintimammography is certainly its low sensitivity for cancers sized

The availability of LaBr3 :Ce crystals from St. Gobain has started various investigations in the field of medical imaging, in particular in PET, SPECT and Compton camera systems. At present LaBr3 :Ce crystals are available in a continuous shape covering up to 10×10 cm2 with a thickness of 1 cm, in contrast, serious concerns are arising in pixellated manufacturing. With the aim of verifying the potentials introduced by LaBr3 :Ce for SPET imaging, two small γ cameras based on Anger camera principle have been assembled and imaging performances were compared. Two crystals of LaBr3 :Ce and NaI(Tl) with the same detection area (5×5 cm2) and thickness of 5 and 1.5 mm, respectively were been integrally assembled with a H8500 Hamamatsu flat panel PMT. Through the thicker crystal, the LaBr3 :Ce camera showed superior imaging and detection performances at 140 keV compared with the NaI(Tl) one, with 0.9 mm FWHM intrinsic spatial resolution, 8% FWHM energy resolution and 80% intrinsic detection efficiency.

In mammals, estrogens have dose- and cell-type-specific effects on immune cells and may act as pro- and anti-inflammatory stimuli, depending on the setting. In the bivalve mollusc Mytilus, the natural estrogen 17beta-estradiol (E(2)) has been shown to affect neuroimmune functions. We have investigated the immunomodulatory role of E(2) in Mytilus hemocytes, the cells responsible for the innate immune response. E(2) at 5-25 nM rapidly stimulated phagocytosis and oxyradical production in vitro; higher concentrations of E(2) inhibited phagocytosis. E(2)-induced oxidative burst was prevented by the nitric oxide (NO) synthase inhibitor N(G)-monomethyl-L-arginine and superoxide dismutase, indicating involvement of NO and O(2)(-); NO production was confirmed by nitrite accumulation. The effects of E(2) were prevented by the antiestrogen tamoxifen and by specific kinase inhibitors, indicating a receptor-mediated mechanism and involvement of p38 MAPK and PKC. E(2) induced rapid and transient increases in the phosphorylation state of PKC, as well as of a aCREB-like (cAMP responsive element binding protein) transcription factor, as indicated by Western blot analysis with specific anti-phospho-antibodies. Localization of estrogen receptor-alpha- and -beta-like proteins in hemocytes was investigated by immunofluorescence confocal microscopy. The effects of E(2) on immune function were also investigated in vivo at 6 and 24 h in hemocytes of E(2)-injected mussels. E(2) significantly affected hemocyte lysosomal membrane stability, phagocytosis, and extracellular release of hydrolytic enzymes: lower concentrations of E(2) resulted in immunostimulation, and higher concentrations were inhibitory. Our data indicate that the physiological role of E(2) in immunomodulation is conserved from invertebrates to mammals.

Organic molecule-metal interfaces are relevant both for theirtechnological applications and for the knowledge of the earlystage of the adsorption. In this context the interface propertiesplay an important role in determining the adsorbate orderingand its electronic properties. In this work we present theelectronic properties and the growth morphology of the CuPcmolecule grown on Al(100) and Au(110) surfaces. These twometals have completely di.erent properties that influence thenature of the interface. Al is a prototype of a free electronmetal and the CuPc/Al(100) interface is characterized by asignificant charge transfer as observed by the disappearanceof the HOMO-LUMO transition in the EELS spectra at lowcoverage [1]. Strong evidence of the interaction between themolecule and Al substrate also come from XPS [2] where weobserve the disappearance of the shake-up satellites in the C1s spectra and the complete reduction of copper for the lowestcoverages. On the contrary Au is characterized by a stronglocalization of d electrons and a low density of delocalized selectrons. For the CuPc/Au(110) interface we observe less important modification of the electronic structure of the moleculewith respect to the CuPc/Al(100) interface. Nonetheless theinteraction between the molecule and the Au substrate is notnegligible. In fact HR-UPS study has shown the presence ofinterface states [3]. From a morphological point of view weobserve that CuPc grown on Au(110) gives rise to di.erentsymmetry of the interface as a function of the CuPc thickness:the 1x2 clean Au reconstruction evolves in a 5x5 and in a 5x3reconstruction as observed by LEED. The Au(110) surface ismade by long channels of missing atoms that act as a guidefor the adsorption of the molecules. Along the direction of thechannels we observe a periodicity that match the dimension ofthe molecule, while along the other direction the x2 reconstructionof the Au atoms disappears after a deposition of a fractionof monolayer and it evolves in the x5 and the x3 reconstruction.As pointed out by GIXD [4], these reconstructions along the [001] direction is due to a rearrangement of the uppermostgold atoms. The CuPc/Al(100) interface does not show anylong range order. For the lowest coverage the strong interactionsuggests a flat lying deposition while for thicker film, XASdata indicate the growth of CuPc layer with the plane of themolecule perpendicular to the surface.

Architectural and engineering geniuses of ancient times have left to the world an important heritage of stone, masonry and other structures ranging from temples, churches, mosques, pyramids to aqueducts, palaces, and dams. Preserving these for future generations is one of the more important challenges facing modern civilization. In some places vibrations from traffic can be a cause of gradual damage, which if not counteracted could result in eventual catastrophic collapse. More often than not, it is earthquakes that pose such a threat that catastrophic failure could occur. Other factors or combination of factors can also cause catastrophic distress to a structure (impacts, blasts, fire, lightening, etc.). Modern engineering design practices usually consider the so called ultimate limit states for a structure as a whole. By using the theory of probability for design parameters such as loads and material properties, one can arrive at the probability of a catastrophic failure of a structure given a particular event. The problem with applying these to significant historical structures is that the computational tools available are at times somewhat limited for ancient structure analyses purposes simply because of the specific and innovative ways the structures were built. In this paper, using the Los Alamos MUNROU package it is demonstrated that the combined finite discrete element method (FDEM) has some unique capabilities in modeling the ultimate limit state of historical buildings ; each individual stone blocks or stone anchors could potentially be captured with accurate representation of frictional energy dissipation under transient dynamic loads. Our work here focuses on an initial cursory analysis of the potential earthquake threat posed to one of the most famous historical structures, the Santa Maria Del Fiore Dome in Florence.

Hypothyroidism and gestational diabetes are common endocrine disorders in pregnancy. Our aim is to evaluate the outcome of newborns from mothers with hypothyroidism and from mothers with gestational diabetes.The study analysed 216 newborns: 112 from mothers with gestational diabetes and 104 from mothers with hypothyroidism. For each case, we included as a control a newborn of same sex and gestational age from a mother without diabetes or thyreopathy.In newborns from mothers with gestational diabetes there was an increased frequency of hypoglycaemia and hypocalcaemia, of lower head circumference and of small-for-gestational age (SGA) birth or macrosomy (LGA) than controls. The newborns from mothers with hypothyroidism are more frequently SGA or LGA and they have a slightly increased risk of hypoglycaemia.Newborns from mothers with diabetes mellitus or hypothyroidism have an increased risk of being SGA or LGA, and to develop a mild transient hypoglycaemia. Newborns from mothers with diabetes mellitus have also an increased risk to develop hypocalcaemia and to have a lower head circumference than controls. Thus, to prevent SGA or LGA births, it is very important an early diagnosis and treatment, and a strict metabolic control of these conditions.