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A critical component of an advanced gas-cooled reactor station is the graphite core. As a station ages, the graphite bricks that comprise the core can distort and may eventually crack. Since the core cannot be replaced, the core integrity ultimately determines the station life. Monitoring these distortions is usually restricted to the routine outages, which occur every few years, as this is the only time that the reactor core can be accessed by external sensing equipment. This paper presents a monitoring module based on model-based techniques using measurements obtained during the refuelling process. A fault detection and isolation filter based on unknown input observer techniques is developed. The role of this filter is to estimate the friction force produced by the interaction between the wall of the fuel channel and the fuel assembly supporting brushes. This allows an estimate to be made of the shape of the graphite bricks that comprise the core and, therefore, to monitor any distortion on them.

In this paper, the results of a detailed comparison of PEEK and VESPEL®SP1 properties as vacuum seals are reported. These synthetic materials have good insulating and mechanical characteristics at relatively high temperatures, which make them very good candidates for UHV applications. Since PEEK has never been used as a vacuum gasket, the main purpose of the paper is to assess its performances, particularly in comparison to VESPEL, which is the reference material for fusion applications. The bench tests include the analysis of the materials behavior at various temperatures up to 250°C. In addition to tightness and permeation tests, thermal desorption and gas chromatographic-mass spectrometer (GC/MS) analysis have been performed, to assess PEEK outgassing with respect to VESPEL®SP1 in UHV environment. The results obtained indicate that in general PEEK performances are comparable to those of VESPEL®SP1 in the investigated operating ranges. VESPEL®SP1 outgassing results in a factor about five times higher than that of PEEK; moreover, the He permeation of PEEK is almost an order of magnitude lower than VESPEL®SP1.

This work concerns with the problem of monitoring an Advanced Gas-cooled Nuclear Reactor (AGR) core. In the world wide context of energy production, the advanced gas-cooled reactor (AGR) nuclear power stations are approaching the end of their predicted operational live. Currently, it has been proposed to extend the operational lifetime of the nuclear plants if the distortions of the reactor cores are not as severe as initially predicted, and if it is possible to prove that the reactors are still safe to operate. The purpose of this work is to present a monitoring system based on analytical redundancy and directional residual generation using measurements obtained during the refueling process. In short this problem consists of building an unknown input observer with the role to estimate the friction force produced by the interaction between the wall of the fuel channel and the fuel assembly. This let to estimate the shape of the graphite bricks that comprise the core and, therefore, monitor any distortion of them.

Gastric cancer is the second most common cancer worldwide. The involvement of ROS (reactive oxygen species) in the pathogenesis of gastric malignancies was well know. Many human tumors have shown significant changes in the activity and expression of SOD that might be correlated with survival and clinical-pathological parameters for the prognosis of human carcinoma. Aim of this study is the detection of the MnSOD and CuZnSOD activity and expression in adenocarcinoma, Helicobacter Pilory (HP), autoimmune-atrophic-gastrite (GTA) and healthy tissues. A total of 21 gastric specimens (5 adenocarcinoma, 9 healthy, 5 HP and 2 GTA) collected during endoscopy or resected during surgery were extracted in phosphate buffer and used to determine the SOD activity and expression by spectrophotometric and western blotting assay. As regards to the carcinoma tissues, the trend of the activity of MnSOD is over 9-fold higher and 2.5-fold higher which respect to CuZnSOD in tumors and HP, respectively. On the contrary in healthy tissues and GTA the CuZnSOD shows a similar or major activity than MnSOD and each isoforms represent nearly the 50% of total SOD activity. After immunoblotting detection of SOD isoforms, MnSOD seem lightly more expressed in adenocarcinoma and HP cases respect to healthy tissues and GTA. SOD activity assay can provide a specific and sensible method of analysis that allows to differentiate healthy tissue from tumour, GTA and HP. The ratio of MnSOD and CuZnSOD activities obtained from this preliminary study, seems to be more explicative in the identification of a pathological from a healthy tissue. SOD in GTA samples present a trend similar to healthy tissues, although in HP seems to be nearly to adenocarcinoma. Further researches will be necessary to define the role of SODs in cancer and the use of the activity as a prognostic marker.

The RFX reversed field pinch (RFP) has undergone major modifications of the load assembly and is now equipped with a large number of active external coils for magnetohydrodynamics mode control. The study of the effects on the plasma of both the new passive structure and the active coils is then of great importance, as well as the investigation of turbulence due to its influence on plasma transport. An integrated system of magnetic, electrostatic and calorimetric sensors has been realized, fulfilling very challenging requirements in terms of spatial and temporal resolution, which are characteristic features of RFP plasmas. A description of the whole diagnostic system is given, including the original solutions adopted to cope with the limited space available and the thermal and electrical requirements, particularly for the calorimetrical probes. The tests performed on the whole system during the installation are presented. Signal conditioning and data acquisition are described.

In this paper the diagnostic systems implemented on the reversed field pinch (RFP) experiment RFX are presented. The paper is mainly concerned with the general engineering aspects and with the development work addressed to meet specific requirements such as immunity to electrical noise, ultrahigh vacuum compatibility, reliability. A general guideline adopted in the development of diagnostics was to use, whenever possible, proven methods, at least for the systems dedicated to the measurement of the most significant parameters. Each section of the paper illustrates a different system, in which the diagnostic constraints and the specific choices derived from the peculiarities of the RFP configuration are discussed. Although the majority of the diagnostic instruments are at present fully developed and operational, some of them, i.e. far-IR polarimeter, microwave reflectometer, soft X-ray and bolometer tomographic system are either under prototype testing or under construction.

Euryoxic organisms are able to withstand hypoxic conditions until the restoration of normal O2 levels, when the re-introduction of oxygen causes a decisive burst in reactive oxygen species (ROS). The consequent oxidative damage is countered by defence systems constituted by antioxidant enzymes, such as SOD, CAT, Se-GPx and G6PDH. Specimens of Scapharca inaequivalvis were exposed to anoxia for 3, 6 and 24 hours and subsequent reoxygenation for 1, 3, 5 and 24 hours. It has been investigated SOD, CAT, Se-GPx and G6PDH activity and MnSOD and CuZnSOD expression in the digestive gland. The results showed SODs activity to be high during both anoxia and reoxygenation. CAT and Se-GPx increase significantly overall during recovery. Only CuZnSOD expression was greater after 6 and 24 hours of anoxia. The presence of high levels of antioxidant enzymes during anozia suggests that the response of S. inaequivalvis is typical of euryoxic animals and represents an interesting model for studying the processes of ischaemia/reperfusion in mammals.

The article shows the results of a longitudinal study aimed to explore the institutional therapeutic alliance (ITA) that is the alliance formed by a patient and all the therapeutic staff. Fifty five patients who have psychiatric disorders in partial hospitalization were evaluated at admission (global functional level, social support, symptomatic condition, and treatment expectancies), at discharge, and after 3 months. ITA was assessed after 1 week of treatment and at discharge, from patient's and staff's perspectives. Preliminary findings suggest that the ITA represents a specific phenomenon different from the classical therapeutic alliance (patienttherapist), which would be particularly relevant for the treatment of patients who are severely disturbed.

We assessed mammaglobin (MMG) gene expression in bone marrow (BM) aspirates from patients with advanced breast cancer who had received a reduced-intensity conditioning and stem cell allografting, in order to detect a graft-versus-tumor effect on micrometastatic disease. Nine patients received a reduced-intensity conditioning with fludarabine, cyclophosphamide, and thiotepa, followed by peripheral blood allografting from HLA-identical sibling donors. Nested RT-PCR analysis with sequence-specific primers for MMG was carried out on a monthly basis on BM samples. Three patients had MMG-positive BM, four patients had MMG-negative BM before allografting, and two were undetermined. In two patients, a clinical response after allografting (partial remission) occurred concurrently with the clearance of MMG expression, at a median of 6 months after allografting, following immune manipulation. In two patients, a prolonged stable disease and negative MMG expression occurred after day +360 from allografting. In two patients, progression of the disease was associated with MMG RT-PCR changing from negative to positive. In one case, a disease response occurring after donor lymphocyte infusion and grade II acute GVHD was heralded by negativization of MMG expression. Although preliminary, these data suggest that a graft-versus-breast cancer effect is detectable on micrometastatic BM disease.

Recently, electrophoretic analyses of waxy wheat proteins in several hexaploid and tetraploid wheat accessions, from worldwide collections, have permitted to identify new variants at the waxy Ioci, including partial null types. In this paper we present a preliminary note on the molecular characterisation of the new mutations identified.

Brazed molybdenum/graphite joints are frequently adopted for plasma facing components in fusion experiments. In particular, the RFX (Reversed Field Pinch Experiment) first wall tiles are fastened onto the vacuum vessel by molybdenum retaining keys having a graphite cap brazed onto the top. The possibility of testing graphite-molybdenum brazed joints by means of radiographic examination has been demonstrated by means of a comparison with the results of destructive methods (metallographies and mechanical tests). The good correlation that was obtained among the three different methods allowed the adoption of this test procedure for the final quality control of approximately 3000 brazed pieces to be exposed to the plasma in the RFX experiment; the tests proceeded very quickly and 100% of the pieces were accepted. The installation of the tiles with their clamps inside the vacuum vessel was then accomplished in four weeks without any major difficulty. >

Reaction of the methylcyclopentadienyl (Cp') cluster compound [(eta(5)-Cp')(3)Mo(3)S(4)][pts] (pts = p-toluenesulfonate) with noble metal alkene complexes resulted in the formation of four new heterobimetallic cubane-like Mo(3)S(4)M' cluster cores (M' = Ru, Os, Rh, Ir). Thus, reaction with [(1,5-cod)Ru(CO)(3)] or [(1,3-cod)Os(CO)(3)] (cod = cyclooctadiene) afforded [(eta(5)-Cp')(3)Mo(3)S(4)M'(CO)(2)][pts] (M' = Ru: [1][pts]; M' = Os: [2][pts]). When [1][pts] was kept in CH(2)Cl(2)/pentane solution, partial loss of carbonyl ligands occurred and the carbonyl-bridged dicubane cluster [((eta(5)-Cp')(3)Mo(3)S(4)Ru)(2)(mu-CO)(3)][pts](2) was isolated. An X-ray crystal structure revealed the presence of the hitherto unobserved Ru(mu-CO)(3)Ru structural element. The formation of cluster compounds containing Mo(3)S(4)Rh and Mo(3)S(4)Ir cores was achieved in boiling methanol by reacting [(eta(5)-Cp')(3)Mo(3)S(4)][pts] with [M'Cl(cyclooctene)(2)](2) (M' = Rh, Ir) in the presence of PPh(3). In this way [(eta(5)-Cp')(3)Mo(3)S(4)M'Cl(PPh(3))][pts] (M' = Rh, Ir) could be isolated. An alternative route to the Mo(3)S(4)Rh cluster core was found in the reaction of [(eta(5)-Cp')(3)Mo(3)S(4)][pts] with [RhCl(1,5-cod)](2), which yielded [(eta(5)-Cp')(3)Mo(3)S(4)Rh(cod)][pts](2) ([7][pts](2)). Substitution of the cod ligand in [7][pts](2) by 1,3-bis(diphenylphosphanyl)propane (dppp) gave [(eta(5)-Cp')(3)Mo(3)S(4)Rh(dppp)][pts](2).

A movable in-vessel electrode has been designed for the RFX experiment in order to modify the radial electric field. The results of the tests performed on prototypes of the components are reported. The reliability of the structure has been assessed by a finite element structural analysis of the system. The power supply to be used for the electrode operation is described.

The commissioning of the RFX power supplies and their integration with the machine windings were performed in steps of increasing complexity; the target was to start the experiments with plasma in the final configuration of all systems, tested up to the performances required for first operation. After a brief description of RFX circuits and operation, the final tests on the power supplies, their commissioning with the control, data acquisition and fast protection systems and the integration with the machine windings are presented. Indications on operation reliability following the first experimental phase are finally given.

The Reverse Field Pinch experiment RFX has been operating since the end of 1991. The paper, after a brief description of the load assembly, presents the most significant aspects of the assembly phase and discusses methods and results of the final tests, carried out before producing the first plasma. Finally, the machine behaviour during the first experimental phase is described.

A movable limiter made of graphite and instrumented with an array of Langmuir and heat flux probes has been developed for the reversed field pinch experiment RFX. The limiter is mushroom shaped and designed to be exposed to the edge plasma for a discharge duration ≊250 ms. The distribution of the probes on the limiter surface allows simultaneous collection, in a single discharge, of edge parameters at different angles and radial positions. A bellows drive system with three degrees of freedom allows the instrumented limiter to be rotated and translated to investigate the spatial structure of the edge plasma. Cables and feedthroughs have been designed for 1‐kV voltage and 5‐A current. The power supply provides an output voltage ±100 V and a maximum current 4 A. Specific software has been developed for the automatic analysis of the Langmuir probes data.

The present work shows some preliminary results of a longitudinal study aimed at validating a psychometric instrument - the Subjective Distance Scale (SDS) - developed to assess the patient's affective nearness/remoteness towards/from the psychiatric treatment in a Day Hospital program. 55 day hospital patients were assessed at different moments of the treatment: At admission they were evaluated by means of the SDS, the SCL-90-R (patient's psychiatric symptoms) and the GAS (patient's mental health level). Institutional therapeutic alliance was assessed one week from admission (IWAI-p) and finally, patient's psychiatric symptoms were retested (SCL-90-R) at the end of the treatment and 3 months from discharge. The main results reveal good psychometric properties of the SDS: its factorial structure partially confirms the dimensions theoretically hypothesised; its internal consistency - total and most of its subscales - reach adequate reliability levels; and related to its predicted validity, the scale correlates with some important aspects of the treatment, like the quality of the early institutional alliance, the symptomatic improvement and the stability of the improvements in time. New studies with larger samples and conducted in additional psychiatric settings are necessary to guarantee the validity and reliability of the scale before it could be used as a clinical screening instrument.

The relevance of a good therapeutic alliance development between patient and therapists in the treatment success has been documented in more than 3 decades of empirical research. In the case of the treatment of severely disturbed patients, the alliance construction process involves particular characteristics determined, in part, by the patients inability to form safety bonds with others and because of, usually, various therapeutic figures are engaged in their treatments. The present work offers a general review of the most important empirical evidence about the therapeutic alliance process in institutional context treatments (i.e., hospitalization, therapeutic community), introduces the concept of Institutional Therapeutic Alliance (ITA) - clinical and empirical phenomenon that accounts for the working bond between the patient and the therapeutic staff perceived as a whole - and reports the major results of a longitudinal study conducted to assess the ITA and explores the relationship with treatment outcomes.55 day-hospital patients take part in the research and were evaluated at admission, before one week, at discharge and after 3 months. The assessment battery included: Symptom Check List (SCL-90), Global Assessment Scale (GAS), Multidimensional Social Perceived Support Scale (MSPSS), Institutional Working Alliance Inventory (IWAI) and Subjective Distance Scale (SDS). The results show that ITA is positively correlated with symptomatic reduction at discharge and negatively associated with patient's re-hospitalization after 3 months.The work concludes by discussing, from a clinical point of view, the promoting and obstructing alliance factors linked with the patient, the staff and their relationships.

Forty patients with histologically proved intracranial tumors were submitted to preoperative lumbar and venous punctures. The concentration of alpha-1-antitrypsin in the serum and in cerebrospinal fluid was determined by radial immunodiffusion technique. In the series, both serum and cerebrospinal fluid alpha-1-antitrypsin concentrations are significantly higher than the mean normal values. No statistical differences are observed in serum alpha-1-antitrypsin levels between benign and malignant tumors, but cerebrospinal fluid alpha-1-antitrypsin is significantly increased in the group of malignant tumors if cases undergoing steroid treatment are excluded. The diagnostic value of alpha-1-antitrypsin determinations in groups of patients with intracranial tumors is suggested.

Among 70 patients referred for suspected multiple sclerosis (MS) a total of 40 met criteria for definite (17), likely (12) or possible (11) diagnosis of the disease. Visual evoked potentials provided evidence of CNS lesion in 13 cases. Abnormalities of somatosensory evoked potentials, particularly on stimulation of the posterior tibial nerve, were present in 90% of patients. Brainstem auditory evoked potentials were of little use, contributing to diagnosis of one subclinical lesion; they were normal in 14 cases with suspected brainstem involvement. A definite diagnosis of MS was made in 4 cases by study of oligoclonal bands. The most frequently involved sites were the optic nerve and the brainstem, followed by the spinal cord. Hemispheral location was demonstrated in only 3 cases. These findings of the first study on MS in our country suggest a different pattern for demyelinating diseases in Chile.

The oxidative addition of PhSeX (X = Cl, Br, I) to Pt0 complexes of formula [Pt(N,N-chelate)(olefin)] is described. The reaction quantitatively affords the trigonal-bipyramidal products [PtX(SePh)(N,N-chelate)(olefin)] with the X and SePh fragments in the axial positions. NMR spectroscopic data have allowed us to gain insights into the geometrical isomerism of some of these complexes. The reactivity of the axial ligands towards electrophilic reagents is also investigated, and the molecular structures of [PtX(SePh)(dmphen)(dimethyl fumarate)] (X = Br, I) are compared. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

The site selective synthesis of functionalized indoles is presented under environmentally convenient tetrabutylammonium fluoride catalysis. The metal-free approach exploits the combined efficiency of Bu4N+ and F− ions in performing a cascade sequence involving intramolecular hydroamination of the C–C triple bond, cleavage of silyl-protecting groups and site-selective sigmatropic aza-Cope-type [3,3]-rearrangement. A range of C(3)-allenyl-(1H)-indoles (2) is obtained in an efficient manner (yield up to 93%) providing a valuable synthetic alternative to noble metal-based protocols.

Preparation of piperidine-2-one scaffolds by the hetero-Diels-Alder (HAD) reaction, assisted by microwaves, is described. The versatility of this new approach has been demonstrated by the synthesis of racemic (+/-)-2-phenylpiperidine. Theoretical calculations have allowed us to clarify the factors that govern ring closure to form four-membered rings, arising from a Staudinger-type electrocyclization, and/or six-membered rings through a classical [4+2] HAD cyclization. This competition may be lowered by increasing the electronic demand of the dienophile, as anticipated by the computational studies.

The reactions of 1-(2-haloethyl)pyrrole-2-carbaldehydes with (1S)-1-phenylglycinol or (1S)-valinol gave the corresponding fused tricyclic oxazolidines as single diastereomers from which 1,2-disubstituted 1,2,3,4-tetrahydropyrrole[1,2-a]pyrazines were obtained by addition of organometallic reagents. The diastereoselectivity was dependent on the nature of both the chiral auxiliary and the organometallic reagent. The best diastereoselectivity (dr ≤ 98:2) was obtained by using Grignard reagents with the oxazolidine derived from (1S)-phenylglycinol. (+)-1-Methyl- and (+)-1-ethyl-1,2,3,4-tetrahydropyrrole[1,2-a]pyrazines were obtained by reductive removal of the N2-substituent.

Intertidal area is characterized by several fluctuations in natural agents and anthropogenic factors (oxygen levels, temperature, salinity, B[a]P presence) that cause a noticeable increase in the expression rate of heat shock protein 70 (HSP70). HSPs acting as molecular chaperones and their induction represent a specific cellular defence mechanism in response to several stress. Chamelea gallina specimens from the North Adriatic coast were exposed to different experimental conditions: varying oxygen levels (48 h of anoxia followed by 24 h of normoxic recovery), temperatures (20, 25, 30 °C for 7 days), salinity (28, 34, 40‰ for 7 days) and B[a]P concentrations (0.5 mg/L for 24 h, 7 and 12 days). Following the extraction of the digestive gland and gills, HSP70 levels were identified in the cytosolic fraction by immunoblotting using primary monoclonal antibodies. An increase in the rate of HSP70 expression under anoxic conditions in the digestive gland was observed at high temperatures, at low salinity and in the presence of B[a]P. The protein was overexpressed in the absence of oxygen and after 12 days of B[a]P exposure, while it was underexpressed in hyposaline conditions in the gills. HSP70 induction can be considered an adaptation mechanism associated with changes in environmental parameters, but also with xenobiotic presence. The overexpression of HSP70 is therefore induced by protein damage due to stressogenic factors. HSP recruitment renders them available for the processes of folding and refolding of denatured proteins or for their transport to a degradation system. The evident sensitivity of HSP70 to natural and anthropogenic stressogenic agents was examined in the present research. The results of this research revealed an interesting response of heat shock protein 70 in C. gallina, underlining the sensitivity of this important commercial species to natural and anthropogenic stress agents. © 2010 Elsevier B.V. All rights reserved.

The recent booming of gold catalysis has demonstrated that unprecedented transformations can be realized in a highly selective manner. Moreover, due to the growing availability of chiral organic ligands, gold-catalysis can be considered as one of most dynamic hot spots in asymmetric synthesis. However, in this context, the use of non-activated olefinic C–C double bonds is still largely unexplored due to the intrinsic inertness of C C (respect to allenes and alkynes) in taking part in nucleophilic additions assisted by π-electrophilic activations. Allylic alcohols have been demonstrated to be feasible “surrogates” of non-activated alkenes for the enantioselective allylic alkylation of indoles catalyzed by chiral gold(I) complexes. In this investigation, a full account addressing efficiency and substrate scope of such a process is presented.

The double addition of organometallic reagents to fused oxazino-oxazines prepared from glyoxal and ( S )-phenylglycinol afforded C 2 - or C 1 -symmetric 1,2-ethylenebis(β-aminoalcohols), depending on the nature of the organometallic reagent. This route was modified by the use of ( S )-valinol and phenylglyoxal as starting materials, and by reduction of the oxazino-oxazines by diborane. Cyclization of the β-aminoalcohol moieties gave 1,2-ethylenediaziridines bearing one substituent/stereocenter on the ring carbon and one, two or no substituents/stereocenters in the ethylene tether. These bis(aziridines) were used as ligands in the Pd-catalyzed allylic alkylation of dimethyl malonate. It was established that the substituent(s) in the carbon tether and the configuration of the corresponding stereocenters have limited influence on the enantioselectivity.

A series of oligomers of the type Boc-(L-Phe-D-Oxd)(n)-OBn (Boc = tert-butoxycarbonyl; Oxd = 4-methyl-5-carboxy oxazolidin-2-one; Bn = benzyl) were prepared for n = 2-5. The shortest oligomer, Boc-(L-Phe-D-Oxd)(2)-OBn, aggregates and forms a fiber-like material with an anti-parallel beta-sheet structure in which the oligopeptide units are connected to each other by only one intermolecular hydrogen bond. The longer oligomers exhibit structural heterogeneity. They start to organize into secondary structures by the formation of intramolecular hydrogen bonds at the pentamer level. Microscopy and diffraction of the oligomers indicated a crystalline character for only the shorter ones.E’ stata sintetizzata la serie di oligomeri Boc-(L-Phe-D-Oxd)

The dipeptide Boc-L-Phe-D-Oxd-OBn spontaneously forms fibers consisting of parallel infinite linear chains arising from single intermolecular N-H…O=C hydrogen bonds, as demonstrated by IR spectroscopy, X-ray diffraction, and solid-state NMR. SEM observations show that the thickness and the width of the filamentous material are almost constant. This is the absolute borderline case of a parallel beta-sheet structure.

A combined catalytic and crystallographic investigation on the effectiveness of chiral diamino-bithiophene (2) and the corresponding diimino molecules (1) as chiral ligands for Pd(II) catalyzed transformations is presented. In particular, a systematic X-ray characterization of the [Pd]-pre-catalytic species provided valuable rationales for the different behavior of the two classes of ligands, underlining the key role played by sterical as well as electronic factors in controlling the oxidative addition of the starting racemic allylcarbonate to the chiral Pd(0) intermediate. Moreover, the versatility of the synthetic strategy for the preparation of enantiopure oligothienyl systems allowed us to synthesize a new type of mixed thiophene/pyridine ligands (2d) that have been effectively employed in asymmetric allylic alkylations (AAA).

The effects of high temperatures on the clam, Chamelea gallina, generally recognised as a low tolerant bivalve species, were studied by evaluating some functional responses of the haemocytes. The animals were kept for 7days at 20, 25 and 30 degrees C and total haemocyte count (THC), phagocytosis, lysozyme activity (in both haemocyte lysate and cell-free haemolymph), activity and expression of the antioxidant enzyme superoxide dismutase (SOD) (in both haemocyte lysate and cell-free haemolymph) were chosen as biomarkers of exposure to high temperatures. The survival-in-air test was also performed. During the experiment, the clams showed differing burrowing behaviour: the animals kept at 20 and 25 degrees C burrowed completely, whereas at 30 degrees C the clams progressively emerged from the sediment and then remained on the surface. The highest temperature significantly increased THC, whereas it decreased the phagocytic activity of haemocytes. The haemocyte size frequency distribution in clams kept at 30 degrees C showed that the cell population of about 8-10microm was markedly reduced compared to clams kept at 20 and 25 degrees C. In clams maintained at 25 degrees C, lysozyme activity was significantly increased in haemocyte lysate, whereas it was markedly decreased in cell-free haemolymph. Total SOD activity significantly decreased in haemocytes from clams held at 30 degrees C whereas it increased in cell-free haemolymph from clams held at 25 degrees C and 30 degrees C. A significant decrease in haemocyte Mn-SOD and Cu/Zn-SOD activities was found with increasing temperature. In cell-free haemolymph, the highest Mn-SOD activity was recorded at 30 degrees C, whereas the Cu/Zn-SOD activity showed no significant changes in clams maintained at different temperatures. SOD isoform expression exhibited different patterns in haemocyte lysate and cell-free haemolymph. The resistance to air exposure of clams kept at 30 degrees C was shown to decrease significantly, LT(50) values fell from 6days in clams kept at 20 degrees C and 25 degrees C to 4days in those kept at 30 degrees C.

The first total synthesis of (R)-convolutamydine A has been achieved by the organocatalytic addition of acetone to 4,6-dibromoisatin. The absolute configuration was determined by single crystal X-ray diffraction. DFT studies were used to model the transition states for the aldol reaction and equilibrium geometries of the post-aldol reaction intermediates. The DFT study revealed that the aldol bond forming reaction was considerably endothermic.

C 2 -Symmetrical, enantiopure 2,6-di[1-(1-aziridinyl)alkyl]pyridines (DIAZAPs) were prepared by a high-yielding, three-step sequence starting from 2,6-pyridinedicarbaldehyde and (S)-valinol or (S)-phenylglycinol. The new compounds were tested as ligands in palladium-catalyzed allylation of carbanions in different solvents. Almost quantitative yield and up to 99% enantiomeric excess were obtained in the reactions of the enolates derived from malonate, phenyl- and benzylmalonate dimethyl esters with 1,3-diphenyl-2-propenyl ethyl carbonate.

The vinyliminium complexes [Fe2{μ-η1:η3-C(R′) C(R′)C N(Me)(R)}(μ-CO)(CO)(Cp)2][SO3CF3] (R = Me, R′ = Et, 1a; R = Me, R′ = Ph, 1b; R = R′ = Me, 1c; R = Xyl, R′ = Me, 1d; R = Xyl, R′ = Et, 1e; R = Xyl, R′ = Ph, 1f; Xyl = 2,6-Me2C6H3), react with MeLi affording the corresponding μ-vinylalkylidene complexes [Fe2{μ-η1:η3-C(R′)C(R′) CHN(Me)(R)}(μ-CO)(CO)(Cp){C5H4(Me)}] (2a–f). The formation of 2a–f is believed to proceed via nucleophilic attack at the Cp ligand, followed by hydrogen migration from the resulting cyclopentadiene to the iminium carbon. Similarly, the complex [Fe2{μ-η1:η3-C(Ph) C(Ph)C N(Me)(Xyl)}(μ-CO)(CO)(Cp)2][SO3CF3] reacts with PhLi to give [Fe2{μ-η1:η3-C(Ph)C(Ph) CHN(Me)(Xyl)}(μ-CO)(CO)(Cp){C5H4(Ph)}] (4). Treatment of 2a with CF3SO3CH3 results in methylation of the nitrogen, yielding the complex [Fe2{μ-η1:η3-C(Et)C(Et)CH(NMe3)}(μ-CO)(CO)(Cp){C5H4(Me)}][CF3SO3] (5). Analogously, the μ-vinylalkylidene complexes [Fe2{μ-η1:η3-C(R′)C(R″) CHN(Me)(R)}(μ-CO)(CO)(Cp)2], (R = Me, R′ = Tol, R″ = H, 3a; R = Me, R′ = SiMe3, R″ = H, 3b; R = Me, R′ = R″ = Et, 3c; R = Me, R′ = R″ = Ph, 3d; R = Bz, R′ = Tol, R″ = H, 3e; R = Bz, R′ = SiMe3, R″ = H, 3f; R = Bz, R′ = COOMe, R″ = H, 3g; R = Bz, R′ = R″ = COOMe, 3h; R = Bz, R′ = R″ = Me, 3i; Bz = CH2Ph), react with CF3SO3CH3 to give the corresponding ammonium-functionalized μ-allylidene complexes [Fe2{μ-η1:η3-C(R′)C(R″)CH(NMe2R)}(μ-CO)(CO)(Cp)2][CF3SO3] (6a–i). The molecular structures of 5 and 6c have been elucidated by X-ray diffraction studies. Finally, protonation of [Fe2{μ-η1:η3-C(Et)C(Et) CH(NMe2)}(μ-CO)(CO)(Cp)2] (3c), with HBF4, affords the complex [Fe2{μ-η1:η3-C(Et)C(Et)CH(NHMe2)}(μ-CO)(CO)(Cp)2]][BF4] (7).

A new class of chiral C 2 -symmetrical diamino-oligothiophenes is described to be effective in catalyzing Pd-mediated asymmetric allylic alkylations in a highly enantioselective manner. The combination of experimental as well as crystallographic evidence revealed the key role played by sulfur-based heteroaromatic rings in the stereodiscriminating step of the procedure. In particular, unprecedented non-covalent secondary interactions between the inner thiophene and the metal center proved to be essential to create the stereochemical environment necessary in order to guarantee excellent levels of chemical and optical yields.

Reaction of a wide variety of aldehydes with the easily prepared 2-azadienes, in the presence of BF3 etherate, furnishes the corresponding hetero Diels–Alder adducts which have been converted, mainly, to cis epoxides via N-Boc protection followed by one-pot two-step ring opening and nucleophilic displacement of the halogen atom, resulting in final formation of an oxirane ring.

Reaction of the cluster salt [(η5-Cp′)3Mo3S4][pts] ([1][pts], Cp′=methylcyclopentadienyl; pts=p-toluenesulfonate) with CuCl yielded a new heterobimetallic cluster, [(η5-Cp′)3Mo3S4Cu(Cl)][pts] ([2][pts]). X-ray crystal structure determination of [1][pts] and [2][pts] showed that the incorporation of CuCl into the Mo3S4 cluster core has only minor consequences on the Mo–Mo and Mo–S distances. The metal atoms in the cluster core of [2]+ form an almost regular tetrahedron. The [2]+ cation conforms to an idealized C3v symmetry ignoring the Cp′ groups since the Cu–Cl bond is almost aligned with the axis defined by the Cu–S(4) cube diagonal.