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The crystallization and the hydrogen absorption properties of a Ni 32 Nb 28 Zr 30 Fe 10 melt spun ribbon were investigated. X-ray diffraction measurements reveal that a small fraction of the ribbon is in a crystalline state, whereas the main component is amorphous. The bulk crystallization process of the alloy ribbon occurs in two steps above 770 K, as measured by differential scanning calorimetry. At each step of the crystallization process, an unusually low activation energy of the order of 180 kJ/mol, was observed. Hydrogen absorption pressure-composition isotherms measured between 598 K and 673 K showed that the enthalpy of hydrogenation is quite high (∼85 kJ/mol), as compared to that of analogous ribbons. The isotherms of these ribbons do not exhibit any plateau, similarly to other amorphous materials, but they exhibited extremely slow kinetics for hydrogen absorption. To simulate the local atomic structure involving cluster formation in amorphous Ni 32 Nb 28 Zr 30 Fe 10 alloy, DFT-MD approach was used to construct an amorphous supercell of this alloy with 108 atoms. Calculations predicted that a fully amorphous structure of Ni 32 Nb 28 Zr 30 Fe 10 can form. The low activation energy of crystallization observed before hydrogenation is due to the presence of only 3 full icosahedra without any Ni-centered icosahedra, that could provide resistance against crystallization. Moreover, a cluster analysis of the Ni 32 Nb 28 Zr 30 Fe 10 alloy after hydrogenation showed interaction of hydrogen atoms with only two icosahedra out of four found in this case, and this could be the probable reason for the extremely slow kinetics of hydrogen absorption. [Display omitted] • Melt spun Ni 32 Nb 28 Zr 30 Fe 10 is mainly amorphous with a minor crystalline inclusion. • Activation energy for crystallization is extremely low (180 kJ/mol). • Large quantities of hydrogen are stored with a slow kinetics. • DFT Molecular Dynamics show the alloy has poor resistance to crystallization. • Hydrogen interacts with two out of four icosahedral clusters with a slow kinetics. [ABSTRACT FROM AUTHOR]

Abstract This paper aims to identify the main issues and drivers of sustainable corporate governance to prevent corruption, analysing the interaction between the principal governance body–Board of Directors–and the implementation and application of corruption prevention plans by pointing out exploratory evidence from the company sample. This paper is built upon two steps. First, the content analysis research method is applied, selecting a sample of Italian companies and analysing information from the corruption prevention plans to establish the role of the Board of Directors in the management of company's system. Second, the level of the implication of Board of Directors in drafting through the identification of the Global Indicator is investigated, measuring the degree of the Board of Directors' involvement and making use of the content analysis's results. Additionally, a linear regression between the Global Indicator, companies dimensional indicator and performance indicators is carried out with the aim to define variables affecting this process. The paper proposes exploratory evidence which shows a deep understanding of the governance body in the construction and application of the corporate corruption prevention plans, taking into consideration crucial information from: the anti-corruption national legislation (Law 190/2012), risk management and organization model (Legislative Decree 231/2001), corporate sustainability and compliance programs adopted by companies. The originality of the findings derives from the need to establish an integrated sustainable corporate governance model directed at preventing corruption. Thus, this paper proposes not only the analysis of the Italian companies' compliance sustainable models to prevent corruption in their corporate governance but shows the path for future research on the topic. Graphical abstract Image 10800 [ABSTRACT FROM AUTHOR]

Ambient Vibration Testing (AVT) and Operational Modal Analysis (OMA) are widely accepted non-invasive diagnostic tools for investigating the actual dynamic behavior of full scale structures and for extracting useful information for the optimal tuning of numerical models. However, despite many successful applications in the case of bridges and slender buildings, ambient vibration testing is still rarely carried out on historical heritage buildings, with a few documented applications on slender structures such as civic and bell towers. In this paper, the authors aim to investigate the potential of AVT and OMA when applied to unconventional heritage structures. In particular, dynamic testing and operational modal analysis of a monumental fountain, the “Fontana Maggiore”, in the City of Perugia, Italy, is presented using data acquired by both contact and non-contact sensing techniques. Results also allow to comment on the most suitable sensing hardware for the considered application. [ABSTRACT FROM AUTHOR]

Ni based amorphous materials have great potential as hydrogen purification membranes. In the present work the melt spun (Ni 0.6 Nb 0.4−y Ta y ) 100−x Zr x with y=0, 0.1 and x=20, 30 was studied. The result of X-ray diffraction spectra of the ribbons showed an amorphous nature of the alloys. Heating these ribbons below T<400 °C, even in a hydrogen atmosphere (1−10 bar), the amorphous structure was retained. The crystallization process was characterized by differential thermal analysis and the activation energy of such process was obtained. The hydrogen absorption properties of the samples in their amorphous state were studied by the volumetric method, and the results showed that the addition of Ta did not significantly influence the absorption properties, a clear change of the hydrogen solubility was observed with the variation of the Zr content. The values of the hydrogenation enthalpy changed from ~37 kJ/mol for x=30 to ~9 kJ/mol for x=20. The analysis of the volumetric data provides the indications about the hydrogen occupation sites during hydrogenation, suggesting that at the beginning of the absorption process the deepest energy levels are occupied, while only shallower energy levels are available at higher hydrogen content, with the available interstitial sites forming a continuum of energy levels. [ABSTRACT FROM AUTHOR]

We measured the far- and mid-infrared spectra of three ionic liquids having bis(trifluoromethanesulfonyl)imide anions and three different cations of the families of pyrrolidinium and ammmonium ions. The molecular vibrations of the individual ions were calculated by means of DFT theory at the B3LYP/6-31G** level: we found good agreement between the experimental and the computed frequencies. The infrared lines are ascribable to molecular vibrations of the single ions, suggesting an extremely weak interaction between anions and cations. The spectral lines found experimentally between 760 and 1050 cm −1 are fingerprints for different cations. The comparison with the calculated frequencies allows the assignment of the experimental spectral lines to specific molecular vibrations of anions and for the first time of the specific cations of the measured ionic liquids. [ABSTRACT FROM AUTHOR]

Objectives: Neuropsychiatric symptoms are common in patients with Alzheimer disease (AD). Treatment for both AD and psychiatric disturbances may affect the clinical observed pattern and comorbidity. The authors aimed to identify whether particular neuropsychiatric syndromes occur in untreated patients with AD, establish the severity of syndromes, and investigate the relationship between specific neuropsychiatric syndromes and AD disease severity. Design: Cross-sectional, multicenter, clinical study. Participants: A total of 1,015 newly diagnosed, untreated outpatients with AD from five Italian memory clinics were consecutively enrolled in the study from January 2003 to December 2005. Measurements: All patients underwent thorough examination by clinical neurologists/geriatricians, including neuropsychiatric symptom evaluation with the Neuropsychiatric Inventory. Results: Factor analysis revealed five distinct neuropsychiatric syndromes: the apathetic syndrome (as unique syndrome) was the most frequent, followed by affective syndrome (anxiety and depression), psychomotor (agitation, irritability, and aberrant motor behavior), psychotic (delusions and hallucinations), and manic (disinhibition and euphoria) syndromes. More than three quarters of patients with AD presented with one or more of the syndromes (N = 790, 77.8%), and more than half exhibited clinically significant severity of symptoms (N = 603, 59-4%). With the exception of the affective one, all syndromes showed an increased occurrence with increasing severity of dementia. Conclusions: The authors' study supports the use of a syndrome approach for neuropsychiatric evaluation in patients with AD. Individual neuropsychiatric symptoms can be reclassified into five distinct psychiatric syndromes. Clinicians should incorporate a thorough psychiatric and neurologic examination of patients with AD and consider therapeutic strategies that focus on psychiatric syndromes, rather than specific individual symptoms. [ABSTRACT FROM AUTHOR]

OBJECTIVES: A deficit in facial emotion recognition was described in patients with Alzheimer disease (AD). However, this issue has been underexplored in subjects with amnestic mild cognitive impairment (a-MCI). Thus, the authors aimed to determine whether a deficit in facial emotion recognition is present in a-MCI phase and whether this is intensity dependent. A secondary aim was to investigate relationships between facial emotion recognition and cognitive performances. DESIGN: Case-control study. SETTING: Memory clinic. PARTICIPANTS: Fifty a-MCI patients, 50 mild AD patients, and 50 comparison subjects (COM) were enrolled. MEASUREMENTS: Information about facial emotion recognition was obtained from Penn Emotion Recognition Test. The Mental Deterioration Battery was used to measure cognitive impairment. RESULTS: Mild AD patients were more impaired in the recognition of almost all emotional stimuli of all intensities than a-MCI and COM subjects. However, there was an increased progression only in low-intensity facial emotion recognition deficit from COM to a-MCI to mild AD patients. In particular, a-MCI subjects differed significantly from COM in low-intensity fearful face recognition performance. This deficit in a-MCI patients was explained by the short-term verbal memory impairment, whereas the same deficit in mild AD patients was explained by the long-term verbal memory impairment. CONCLUSIONS: Emotion recognition progresses from a deficit in low-intensity fearful facial recognition in a-MCI phase to a deficit in all intensities and emotions in mild AD. This could be an effect of the progressive degeneration of brain structures modulating emotional processing. An early detection of emotional impairment in MCI phases of dementia may have clinical implications. [ABSTRACT FROM AUTHOR]

The article examines the effect of glutathione S-transferase (GST) P1-M1-T1 gene polymorphisms and their interactions with the apolipoprotein E e4 allelic variant during a three-year longitudinal course of 99 late-onset Alzheimer's disease (LOAD) patients. The study showed that GSTP1 was associated with a faster decline in cognitive functioning and basic activities of daily living. GSTs may show that oxidative stress plays a major role in Alzheimer's disease neurodegeneration.

The high-temperature anelastic spectrum of the solid solution Sc–O has been investigated on a polycrystalline sample at oxygen concentrations between 0.024 and ∼0.9 at.% O, as estimated by residual resistivity and intentional O doping. Two thermally activated relaxation processes appear near 430 and 520 K for a vibration frequency of 3.5 kHz; both peaks are stable with thermal cycling and their intensities increase with the oxygen content, indicating that they are due to O jumps. The process at lower temperature has an intensity that strongly increases with increasing temperature, when measured at higher frequency (42 kHz), indicating that the relaxation occurs between states differing in energy by ∼0.3 eV. The peak is describable by a single relaxation time, and is interpreted as due to the stress-induced hopping of single oxygen atoms between the non-equivalent tetrahedral and octahedral interstitial sites. The process at high temperature is tentatively attributed to O pairs. An estimate of the specific resistivity of O atoms has been provided. [Copyright &y& Elsevier]

A mixture of MgH 2 and Mg 2 FeH 6 was synthesized by reactive ball milling of magnesium hydride and iron in hydrogen atmosphere. The material is highly nanocrystalline, with typical dimensions of the order of 10 nm; after hydrogen cycling at ∼400 °C, well defined XRD peaks of Mg 2 FeH 6 can be observed. Volumetric measurements of hydrogenation/dehydrogenation provide clear evidence of the presence of both hydrides even at lower temperatures. The relative content of magnesium-iron hydride increases on increasing H 2 cycling temperature, passing from ∼44% at 335 °C to ∼54% at 390 °C. Already at 250 °C the composite releases ∼3wt% H 2 in ∼1000 s, while above 340 °C, more than 4wt% H 2 can be discharged in less than 100s, following the Johnson-Mehl-Avrami-Kolmogorov equation, with an exponent n = 1, compatible with a reaction controlled transformation. Finally, also the electrochemical performances in a lithium cell have been investigated: the material is able to undergo a conversion reaction and gives on the first discharge more than 1400 mAhg −1 . The overpotentials decrease after materials activation by H 2 sorption treatments. Moreover, for the first time, the partial reversibility of the conversion reaction for materials containing magnesium iron hydride is here reported. [ABSTRACT FROM AUTHOR]