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Background: Residual stress development in precipitation strengthened aluminium foundry alloys has seen little attention, despite the prevalence of their use over a wide array of applications. Objective: This study aims at the evaluation of the residual stress in a cast aluminium benchmark that develops during precipitation heat treatment and determines the preferable stress relaxing techniques for such applications. Methods: The stress states in the as-cast, T4 and T6 tempers of the same AlSi7Cu0.5Mg (A356 with 0.5 wt% Cu) sample were determined through a novel application of the contour method, standard hole drilling, deep hole drilling and incremental deep hole drilling. Results: The results of all measurement techniques lie within approximately 40 MPa for all regions available for comparison, with the greatest differences occurring between the contour method and deep hole drilling for the T6 component. It is shown that the peak tensile residual stresses are almost identical between the heat-treated components (75 MPa), but the distribution and magnitude of compressive residual stress are found to be significantly different. Conclusions: Among the measurement techniques evaluated, the contour method and incremental hole drilling are found to be more suitable for T6 temper, while all techniques perform equally well for T4 temper due to its relatively low strength. It is hypothesised that the difference between the as-cast and heat-treated samples is due to solution heat treatment and quenching, while the difference in T4 and T6 tempers is attributed to the response to ageing. [ABSTRACT FROM AUTHOR]

Two new mononuclear complexes, [Cu2Cl1.23(NO3)0.77(Ampy)4(H2O)4](NO3)2·4H2O (I) and [CdI2(Ampy)2] (II) (Ampy = 4-amino-6-methoxypyrimidine) have been synthesized and characterized by single crystal X-ray diffraction studies (CCDC nos. 2023331 (I), 2023331 (II)) at 295 K for (I) and 100 K for (II). The structure of the Cu(II) complex shows that the Cu(II) central atom is five-coordinated with a distorted square pyramidal geometry. In compound (II) the Cd(II) cations are tetracoordinated with a distorted tetrahedral fashion. Intermolecular interactions were investigated by Hirshfeld surfaces. Electronic properties such as HOMO and LUMO energies were derived. [ABSTRACT FROM AUTHOR]

Background: 123I-MIBG myocardial scintigraphy and clonidine growth hormone test (CGH test) may help to distinguish multiple system atrophy (MSA) from Parkinson’s disease (PD). Their relevance in the first-stage parkinsonism of uncertain etiology is unknown.Methods: Patients experiencing parkinsonism of ambiguous etiology were clinically classified into the PD group or the MSA group as initial clinical diagnosis (ICD). Then, CGH test and myocardial scintigraphy were performed. Clinical assessment was repeated throughout the disease course until the final clinical diagnosis (FCD) could be established according to the criteria of PD and MSA, respectively.Results: Twenty-five patients with uncertain diagnosis were included (15 MSA and 10 PD as ICD). At the end of a 6-year follow-up, FCD was MSA in 11/25 patients and PD in 14/25. The CGH test and the scintigraphy showed a sensitivity of 82%, and a specificity of 71 and 93%, respectively, for the diagnosis of MSA. The combination of a normal scintigraphy (i.e., with myocardial MIBG uptake) with genitourinary dysfunction was the most relevant test to diagnose MSA, whereas an abnormal scintigraphy with a levodopa response of > 30% or an abnormal scintigraphy with the absence of OH was the most relevant combinations to diagnose PD. All these combinations had an accuracy superior than 90% and a specificity of 100%.Conclusion: Combinations of myocardial scintigraphy with genitourinary dysfunction, levodopa response of > 30%, or orthostatic hypotension could be of interest for the distinction between PD and MSA when the clinical diagnosis remains ambiguous at the first stage of the disease. [ABSTRACT FROM AUTHOR]

The physicochemical properties of a new cyclohexaphosphate, (CHN)(HO)(PO), prepared by an acid-base reaction between cyclohexaphosphoric acid HPO and 2,4,6-trimethylaniline, are discussed on the basis of X-ray crystal structure investigation. The crystal structure determination reveals that the complete cyclohexaphosphate anion, with chair conformation, is generated by crystallographic inversion symmetry. The asymmetric unit consists of two organic cations, one half-anion and one hydronium cation. The atomic arrangement can be described by thick layers built by PO anions and HO cations parallel to the (a, b) plane. Each cyclohexaphosphate group is connected to its adjacent neighbors by six hydronium ions through strong O-H...O hydrogen bonds. The protonated amines are located between these successive inorganic layers, in order to balance the negative charge of the inorganic framework by establishing N-H...O hydrogen bonds with the O atoms of the PO anions. The three-dimensional cohesion is assured by different interactions (electrostatic, H-bonds, van der Waals) established between the various molecular components. This compound is also characterized by infrared spectroscopy and solid state MAS-NMR. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Specimens of the freshwater unionid bivalve Hyridella depressa were experimentally exposed to a synthetic river water containing an elevated Mn water concentration (20 mg l) for 2 or 6 days. SIMS depth profiles through the incremental nacre microlaminations or tablets (∼0.6 μm breadth) of the shells of these bivalves showed increases in the signal intensity of Ca-normalised Mn that corresponded to the period of exposure. These results support the proposition that bivalve shells can be used as retrospective monitors of water chemistry. They also indicate that 1) there is a lag phase between exposure to the elevated Mn water concentration and its expression in the shell, and 2) the period for Mn in the shell to reach equilibrium with the aquatic medium is greater that 2 to 6 days. [ABSTRACT FROM AUTHOR]

Human α2-macroglobulin-human pancreatic elastase II binding were investigated using a homologous substrate, human aortic elastin, in order to test the enzymatic activity. We demonstrated that two moles of α2-M are required to inhibit one mole of HPE when the enzyme is added to a mixture of elastin and α2-M. In addition, when the elastase-α2-M complex is prepared under some circumstances, it exhibits an elastinolytic activity. [ABSTRACT FROM AUTHOR]

The effect of some divalent cations, especially Mg, on elastinolysis by porcine or human pancreatic elastase has been determined usingIodine-labeled elastin as substrate. Elastin degradation was significantly increased in the presence of 10 M Mg. If elastin was pre-incubated with 0.5 (w/v) Triton, there was a further increase in elastinolysis to 2.6 times the original rate. [ABSTRACT FROM AUTHOR]

Spinal neurenteric cyst is a rare congenital lesion that may occur either alone or in the context of a complex malformative disorder. Our case is unusual because of its rare intramedullary location, the association with an important intrathoracic development, and the age of the child at presentation (1 month). An anterior approach through a right-sided lateral thoracotomy was performed for a total resection of the intrathoracic part and a subtotal resection for the intramedullar portion. During 2 years of follow-up, the child presented no neurological deficit and post-operative magnetic resonance imaging found a small residue fixed on the anterior spinal cord without progression. [ABSTRACT FROM AUTHOR]

A prospective, observational study which assessed the medical time spent by intensivists outside the intensive care unit (ICU) and its workload, is presented. Topics covered include time spent by ICU physicians in for the care of patients in other departments and for the management of patients during an intra-hospital transport (IHT) and how the medical time of ICU physicians outside the ICU was organized and distributed.

The new organic cyclohexaphosphate (C6H7ClFN)4 (Li)2(P6O18)(H2O)4, has been synthesized at room temperature by an acid/base reaction between H6P6O18 and 3-chloro-4-fluoroaniline as an organic template. The crystal structure of (C6H7ClFN)4 (Li)2(P6O18)(H2O)4 was solved by single crystal X-ray diffraction analysis. A double head-to-head layer of cations is formed by hydrophobic interactions. Hirshfeld surface analysis reveals the nature of intermolecular contacts of the title compound. The contacts enrichment ratio shows that both strong electrostatic interactions and hydrophobic contacts are overrepresented. This hybrid material was then characterized by 1H, 13C, 31P, 15N and 19F solid-state NMR and IR spectroscopies. Electrical conductivity was also studied using impedance spectroscopy and results showed that the conductivity at 105 °C was equal to 96.5 × 10−4 S.cm−1. Antioxidant properties of this compound were studied, in vitro, at various concentrations with different tests; 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing power (FRAP), Trolox equivalent antioxidant capacity (TEAC) or ABTS+, using 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox) as control. [ABSTRACT FROM AUTHOR]