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Diazo compounds are organic substances that are often used as precursors in organic synthesis like cyclization reactions, olefinations, cyclopropanations, cyclopropenations, rearrangements, and carbene or metallocarbene insertions into C−H, N−H, O−H, S−H, and Si−H bonds. Typically, reactions from diazo compounds are catalyzed by transition metals with various ligands that modulate the capacity and selectivity of the catalyst. These ligands can modify and enhance chemoselectivity in the substrate, regioselectivity and enantioselectivity by reflecting these preferences in the products. Porphyrins have been used as catalysts in several important reactions for organic synthesis and also in several medicinal applications. In the chemistry of diazo compounds, porphyrins are very efficient as catalysts when complexed with low-cost metals (e.g., Fe and Co) and, therefore, in recent years, this has been the subject of significant research. This review will summarize the advances in the studies involving the field of diazo compounds catalyzed by metalloporphyrins (M−Porph, M = Fe, Ru, Os, Co, Rh, Ir) in the last five years to provide a clear overview and possible opportunities for future applications. Also, at the end of this review, the properties of artificial metalloenzymes and hemoproteins as biocatalysts for a broad range of applications, namely those concerning carbene-transfer reactions, will be considered. [ABSTRACT FROM AUTHOR]

With psychological assessment and testing being part of psychologists' identity, Portuguese and international studies have highlighted less investment in assessing children during their early years. This research aims to characterize the use of testing and other psychological assessment tools on children between 0-7 years old in Portugal. The sample is composed of 63 psychologists who answered an online inquiry within the scope of a broader study. The analysis of instruments most used allowed to reinforce that these mainly consist of tests (and less of rating scales), and also that the cognitive field is more represented than the social-emotional one, with the Wechsler WISC-III and WPPSI-R scales and the Griffiths Mental Development Scales being the most frequently mentioned instruments. The discussion of the results points to the need of further investigation aimed at guaranteeing the psychometric quality of instruments used, and of significant investment in training the field's professionals. [ABSTRACT FROM AUTHOR]

Hyperbaric storage at room temperature (HS/RT: 75 MPa/25 °C) of vacuum-packaged fresh Atlantic salmon (Salmo salar) loins was studied for 30 days and compared to atmospheric pressure at refrigerated temperatures (AP/5 °C, 30 days) and RT (AP/25 °C, 5 days). Most of the fatty acids were not affected by storage conditions, with only a slight decrease of docosahexaenoic acid (DHA) content (n-3 polyunsaturated fatty acid) for AP samples, reflected in the lower polyene index values obtained and higher oxidation extent. For HS, a lower lipid oxidation extension and a slower increase of myofibrillar fragmentation index values were observed, when compared to AP samples. The volatile profile was similar for the HS and fresh samples, with the HS samples retaining fresh-like alcohols and aldehydes components, which disappeared in AP samples, mainly in AP/25 °C samples. The volatile profile for AP samples (5 and 25 °C) revealed mostly spoilage-like compounds due to microbial activity. Drip loss increased progressively during the 30 days of storage under HS, while a slight decrease of water holding capacity after 5 days was observed, increasing further after 30 days. Regarding textural properties, only resilience was affected by HS, decreasing after 30 days. So, HS/RT could represent an interesting extended preservation methodology of fresh salmon loins, since allows retaining important physicochemical properties for at least 15 days, while refrigeration after 5 days showed already volatile spoilage-like compounds due to microbial activity. Furthermore, this methodology allows additional considerable energy savings when compared to refrigeration. [ABSTRACT FROM AUTHOR]

The Eysenck Personality Questionnaire – Revised (EPQ-R) assesses the three fundamental personality dimensions: Psychoticism, Extraversion, Neuroticism, including a Lie/Social Desirability scale. This paper presents the results of the normalization study of EPQ-R in the Portuguese population, which were obtained through a large and representative community sample. A sample of 1689 subjects participated in this study (783 men and 906 women, ages 16-60 years old) from several geographic areas in Portugal. The norms of the Portuguese Version of EPQ-R were constructed considering gender and age, and significant statistical differences between several groups were found. Through a model of Item Response Theory, a DIF analysis was performed and showed the psychometric quality of the EPQ-R items in measuring the N, E, P, and L constructs, concerning gender and age variables. [ABSTRACT FROM AUTHOR]

The present study examined the psychometric properties of a brief measure of the Triarchic model of psychopathy based on the Youth Psychopathic Traits Inventory (YPI-Tri-S) among a forensic sample of detained female youth offenders (M = 16.41 years; SD = 1.19 years) from Portugal. Results supported the expected three-factor structure and cross-gender measurement invariance. The YPI-Tri-S showed good psychometric properties in terms of factor structure, internal consistency, convergent validity, discriminant validity, and criterion-related validity. Findings suggest that the YPI-Tri-S is a valid and reliable measure of the Triarchic model of psychopathy, which can be used to assess female juvenile offenders. [ABSTRACT FROM AUTHOR]

The propensity to morally disengage can be an essential driver of unethical, antisocial, and criminal behavior. The present study examines the psychometric properties of the Propensity to Morally Disengage Scale (PMDS) among a convenience sample of 242 male and female participants (M = 30.19 years, SD = 12.78, range = 16–77) from Portugal. The expected one-factor structure obtained an adequate fit using confirmatory factor analysis. Internal consistency/reliability was adequate as measured by the alpha and omega coefficients. Convergent validity (i.e. with dark traits, low self-control, violence evaluation, and antisociality/criminality tendencies measures), divergent validity (i.e. with basic empathy and light traits of personality measures), and criterion-related validity (e.g. with trouble with the law, arrested by police, sentenced to prison variables) were demonstrated with Pearson and point-biserial correlations. Measurement invariance across gender was established. Significant gender differences in the PMDS scores were found, with males scoring significantly higher than females. Our findings support using the PMDS Portuguese version as a short, valid, and reliable measure of moral disengagement. [ABSTRACT FROM AUTHOR]

Abstract More realistic assessment tools are imperative for a better understanding of the impact of age-related cognitive deficits on functional status. With this in mind, we probed the ability of the EcoKitchen, a non-immersive virtual environment task with increasing executively demanding kitchen chores, to detect the effects of aging on the simulated everyday functioning of healthy adults. Fifty-three adults (age between 23 and 77 years) were assessed with the EcoKitchen and a set of conventional paper-and-pencil neuropsychological tests. The associations between the baseline features of study participants and each of the two different assessment methods were examined. The associations between the EcoKitchen variables and an executive composite score were also explored. Our results showed that older individuals present deficits in the performance of both the EcoKitchen task and standard assessment methods. Notably, we found that, unlike conventional tests, accuracy in the EcoKitchen task was not related to the education level and IQ score of participants. Moreover, the EcoKitchen performance time was significantly correlated with executive tests. We have demonstrated that the EcoKitchen task, an ecologically relevant computerized neuropsychological assessment tool, might be more suitable than classic paper-and-pencil tests to capture the impact of aging on everyday cognitive function, as it proved to be less prone to the influence of confounding factors. Additionally, we have shown that executive function plays an important role in the timely performance of cognitively challenging virtual environment tasks. [ABSTRACT FROM AUTHOR]

Background: There are numerous scales for screening cognitive performance and thus identification of any potential deficits, but in spite of the vulnerability of the prison population to such problems, there has been no adequate validation of screening tools specifically for use with prisoners or others in the criminal justice system. Aim: To validate the Montreal Cognitive Assessment (MoCA) for use with prisoners. Methods: 100 adult prisoners in one Portuguese prison were randomly invited by clinicians to take part in this study. A same size sample of community‐living adult non‐offenders of similar age was selected from the MoCA's normative study database in Portugal. For both groups, the key inclusion criterion was fluency in the Portuguese language. All participants completed the Mini Mental State Examination (MMSE) and the MoCA, both in Portuguese translation. Cronbach's alpha coefficient was calculated as an index of internal consistency and Pearson's r correlations calculated. Group performances were compared using independent samples t‐test. Covariance analysis (ANCOVA) was computed with level of education as covariate. To measure the magnitude of the effect, ηp2 ${\eta }_{p}^{2}$ was used. A receiver operating characteristics curve analysis was computed to evaluate the discriminatory accuracy of MoCA and MMSE. Results: The MoCA showed a 'reasonable' internal consistency index (α = 0.75) as well as positive and significant correlations with the MMSE. As a cognitive measure, however, the MoCA showed consistently superior psychometric properties and higher discriminatory accuracy (MoCA = 89%) than the MMSE (65%). According to the Youden index, the optimal cut‐off point for the MoCA is below 24 points, whereas for the MMSE, it is below 27. Conclusions: The MoCA is a valid cognitive screening tool for use with prisoners. Further validations against detailed cognitive evaluation would be a useful next step. [ABSTRACT FROM AUTHOR]

The unstructured families have been increasing and, consequently, also the school failure in young adolescents from these families. These present more and more psychological disorders of difficult control. In this study we highlight the loss of quality of life of these young people and risk deportments. This essentially quantitative research allowed perform an intervention in the school through relaxation techniques applied by Simões (2003, 2013) and associated to the contents of positive psychology and used by Neto and Marujo (2004, 2011). These include guided meditation techniques already applied in the health area. From research about the representation of teachers and the role of parents in the school (Faria; Pedro, 1995), and later on the representation of parents on teachers' identity (Faria; Tavares, 2011), It can be concluded that both have specific roles and an important mission in the educational process. Following these studies, we questioned the interest of parents and teachers (educational stakeholders) about which values they consider most important to develop in school with their children and that may be directly associated with their deportments. For this purpose, we applied an appreciative survey (from the scope of positive psychology), as used by Marujo; Neto; Caetano e Rivero (2007), which allowed us to determine the most important values to be applied to young people, more balanced deportments and better learning. The calculated values seem directly associated with the forces of character designated by Seligman & Peterson (2004) in the scope of positive psychology. This auscultation of the opinion of the educational agents allowed the realization of the “base-line" for the construction of the visual analogue scale that measured the evolution of the students throughout the intervention. The results point to significant differences, over time, in the groups where the intervention was performed. [ABSTRACT FROM AUTHOR]

The literature lacks information on the performance of patients with brain tumors on the Wechsler Intelligence Scales. This study aimed to explore the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III) performance profile of 23 consecutive patients with brain tumors and 23 matched controls selected from the Portuguese WAIS-III standardization sample, using the technical manual steps recommended for score interpretation. The control group was demographically matched to the tumor group regarding gender, age, education, profession, and geographic region. The technical manual steps recommended for score interpretation were applied. Patients with brain tumors had significantly lower performances on the Performance IQ, Full-Scale IQ, Perceptual Organization Index, Working Memory Index, Processing Speed Index, Arithmetic, Object Assembly, and Picture Arrangement, though all scaled scores were within the normal range according to the manual tables. Only Vocabulary and Comprehension scatter scores were statistically different between groups. No strengths or weaknesses were found for either group. The mean discrepancy scores do not appear to have clinical value for this population. In conclusion, the study results did not reveal a specific profile for patients with brain tumors on the WAIS-III. [ABSTRACT FROM AUTHOR]

Porphyrin-based Metal-Organic Frameworks (Por-MOFs) constitute a special branch of the wide MOF family that has proven its own value and high potential in different applications. In this mini-review the application of these materials as catalysts in oxidation reactions is highlighted. [ABSTRACT FROM AUTHOR]

The Metacognitive Awareness Inventory (MAI) of Schraw and Dennison (1994) assesses two general metacognitive dimensions in adolescents and adults: knowledge of cognition, which includes three subprocesses, and regulation of cognition, which has five subprocesses. This study shows the process of translation and adaptation of MAI to the Portuguese population. Internal consistency in the dimensions knowledge and regulation of cognition was 0.82 and 0.90, respectively. The results of Confirmatory Factor Analysis suggest a factor of second order based on the correlation of two main dimensions. The declarative knowledge subscale showed better criterion validity compared to the other subscales. The MAI constitutes an adapted instrument to the Portuguese reality both for the assessment of a global metacognition score and in their two main dimensions, allowing research into the performance in learning and training processes in adults and adolescents. [ABSTRACT FROM AUTHOR]

Background: Regional body composition can influence disease risk and simple screening methods to identify individuals at risk are still needed. Aim: To develop equations for estimating fat and lean mass distribution, using DXA as a criterion, and to compare their performance by the association with cardiometabolic risk factors (systolic and diastolic blood pressure, high-density lipoprotein cholesterol, triacylglycerides and fasting glucose). Subject and methods: The study was conducted among 391 adults (52% female; aged 24–64 years), randomly selected from the EPIPorto cohort, with anthropometric (skin-folds and circumferences) and DXA measures. Multiple linear regression models, by sex, were used to derive predictive equations and to investigate their performance by the associations with cardiometabolic risk factors. Results: The best predicting models included circumferences and skin-folds. The final equations standard error (SEEs) ranged between 1.7–3.2% in men and 2.0–3.7% in women. Similar associations were found between regional body composition, measured by DXA or estimated by anthropometric equations, with traditional cardiometabolic risk factors, supporting the convergent validity of the equations. Additionally, it was found that central fat was associated adversely, whereas peripheral fat was favourably associated with cardiometabolic risk factors and their clustering. Conclusions: Equations combining both circumferences and skin-folds met the necessary standards for predicting regional body composition accurately, being an important tool to identify individuals with cardiometabolic risk. [ABSTRACT FROM PUBLISHER]

Li 3 MnO 4 , a Mn 5 + -containing phase, is a promising cathode material for Li-ion batteries due to its very high theoretical capacity of 698 Ah/kg. However, the possibility to exploit only part of the theoretical capacity and its rapid capacity fading prevents the use in Li-ion batteries. An ex-situ post mortem analysis combining XRD, SEM, XPS and Raman measurements revealed that lithium extraction or insertion gives rise to amorphization of the structure with conversion to a more stable amorphous MnO 2 phase, already after the first cycle. Formation of solid electrolyte interface on the surface of the particles during discharge and its dissolution during charge was also demonstrated. In conclusion, a model for the degradation mechanism of Li 3 MnO 4 in Li-ion batteries was proposed. [ABSTRACT FROM AUTHOR]

Based on the P-E-N Model, the Eysenck Personality Questionnaire - Revised (EPQ-R; S. Eysenck, H. Eysenck, & Barrett, 1985) assesses the three fundamental personality dimensions: Psychoticism (P), Extraversion (E), and Neuroticism (N). This test also includes the L scale, which is a Lie/Social Desirability scale. This paper presents the results of psychometric studies obtained with the Portuguese Experimental Version of the EPQ-R (Almiro & M.R. Simões, 2007) in a sample of 671 participants. These studies include: reliability analysis (internal consistency and test-retest methods); construct validity analysis (principal components analysis) and concurrent validity analysis (using the test scores in BDI, STAI and BSI as an external criterion of validation); and item analysis (item fit, item reliability, item validity) applying the Rasch Model. These results show the good psychometric properties of the Experimental Version of the EPQ-R. [ABSTRACT FROM AUTHOR]

The term “executive function” has been used to describe several higher-order cognitive processes. This study examined the processing speed, shifting, planning, and verbal fluency of a sample of 50 Portuguese children with developmental dyslexia (DD) and 50 typically developing children (TDC; chronological-age-matched controls) between 8 and 12 years of age to evaluate the children’s executive functioning. Compared to TDC, children with DD revealed significant processing speed, shifting, and verbal fluency deficits. After controlling for differences in the general intellectual ability, significant group differences remained for shifting, verbal fluency and marginally for processing speed. No significant differences in planning ability were observed between the groups. No significant interaction of group, gender, and age was found for any of the executive functions measures studied. Word productivity in both semantic and phonemic verbal fluency tasks decreased significantly over the 60 seconds for both groups. Shifting was the only significant predictor of DD in the binary logistic regression analysis and yielded the highest area under the curve value (receiver operating characteristics curve analysis). Therefore, although these findings highlight the presence of specific executive functions deficits in children with DD, they should not be interpreted as indicative of the presence or absence of this learning disorder. [ABSTRACT FROM AUTHOR]

Vanadium manganese oxides with Mn content up to 33 at% were synthesized by a low temperature hydrothermal route allowing for the preparation of both anodic and cathodic materials for Li-ion batteries. Low amounts of manganese (below 13 at%) lead to the formation of elongated particles of layered hydrated vanadium oxides with manganese and water intercalated between the V 2 O 5 slabs, while for higher Mn content of 33 at%, monoclinic MnV 2 O 6 is formed. Former materials are suitable for high energy cathodes while the latter one is an anodic compound. The material containing 10 at% Mn has the composition Mn 0.2 V 2 O 5 ·0.9H 2 O and shows the best cathodic activity with 20% capacity improvement over V 2 O 5 ·0.5H 2 O. Lithiated MnV 2 O 6 with Li 5 MnV 2 O 6 composition prepared electrochemically was evaluated for the first time as anode in a full-cell against Mn 0.2 V 2 O 5 ·0.9H 2 O cathode. An initial capacity ca. 300 A h kg −1 was measured with this battery corresponding to more than 500 Wh kg −1 . These results confirm the prospect of using Li 5 MnV 2 O 6 anodes in lithium-ion batteries as well as high-capacity layered hydrated vanadium oxides cathodes such as V 2 O 5 ·0.5H 2 O and Mn 0.2 V 2 O 5 ·0.9H 2 O. [ABSTRACT FROM AUTHOR]

Li 3 MnO 4 , a lithium rich phase containing manganese (V), is a promising cathode material for Li-ion batteries due to its very high theoretical capacity (698 A h kg −1 ). Li 3 MnO 4 was synthesized from freeze dried precursors at 398 K. Combined structural, morphological and chemical characterization by XRD, TGA, SEM, TEM and XPS revealed improvements in the micro- and nanostructure in comparison to the material synthesized by a standard solid state chemistry route. The average particle size decreased from 10 μm to 3.5 μm and the average crystallite size from close to 100 nm to around 30 nm. These modifications enhanced the capacity (23% at 10 A kg −1 and up to 31% at 50 A kg −1 with a maximum discharge capacity of 290 A h kg −1 ) and the rate capability. [ABSTRACT FROM AUTHOR]

The International Working Group on Alzheimer's disease ( AD) suggested the free and cued selective reminding test ( FCSRT) to assess memory, as it showed high sensitivity and specificity in the differentiation of AD from healthy controls and other dementias. The FCSRT involves the use of selective reminding with semantic cueing in memory assessment. This study aims to validate the FCSRT for mild cognitive impairment ( MCI) and AD through the analysis of the diagnostic accuracy and the suggestion of cut-off scores. Patients were classified into two groups according to standard criteria: MCI ( n = 100) and AD ( n = 70). A matched control group ( n = 101) of cognitively healthy subjects was included. The reliability and the validity of the FCSRT were analysed on the immediate ( IR) and delayed ( DR) recalls. The Cronbach's alpha was 0.915 for the IR and 0.879 for the DR. The total recall measures revealed good areas under the curve for MCI ( IR: .818; DR: .828) and excellent for AD ( IR: .987; DR: .991). Furthermore, the MCI group was subdivided with respect to a non-similar/similar AD pattern of impairment, with almost half of the subjects showing an AD-like decline. This analysis represents a novel contribution regarding the properties of the FCSRT in illustrating the heterogeneity of MCI at baseline. The FCSRT has proved to be a very useful tool in the characterization of the memory impairment of the AD spectrum. [ABSTRACT FROM AUTHOR]

Synthetic metalloporphyrins are catalysts that can efficiently insert oxygen and other atoms such as nitrogen and sulfur in hydrocarbons and in a wide variety of other organic compounds. This work reports on a synthetic strategy to prepare new metalloporphyrins via structural modification of [5,10,15,20-tetrakis (pentafluorophenyl)porphyrin], or [H 2 (TPFPP)], with 4-mercaptobenzoic acid; it also describes their characterization and catalytic activity. The substituent groups present in the structure of the resulting porphyrins furnished structured solids, which could potentially serve as catalysts in heterogeneous medium. Investigation of the catalytic activity of the new derivatives in the oxidation of (Z)-cyclooctene, cyclohexane, and heptane, under homogeneous conditions, and in the oxidation of (Z)-cyclooctene, in heterogeneous medium, proved that the new metalloporphyrins constituted excellent catalysts for (Z)-cyclooctene epoxidation. As for alkane oxidation, they selectively gave the corresponding alcohol in good yields. [ABSTRACT FROM AUTHOR]

Skin cancer is one of the cancers that registers the highest number of new cases annually. Among all forms of skin cancer, melanoma is the most invasive and deadliest. The resistance of this form of cancer to conventional treatments has led to the employment of alternative/complementary therapeutic approaches. Photodynamic therapy (PDT) appears to be a promising alternative to overcome the resistance of melanoma to conventional therapies. PDT is a non-invasive therapeutic procedure in which highly reactive oxygen species (ROS) are generated upon excitation of a photosensitizer (PS) when subjected to visible light of an adequate wavelength, resulting in the death of cancer cells. In this work, inspired by the efficacy of tetrapyrrolic macrocycles to act as PS against tumor cells, we report the photophysical characterization and biological assays of isobacteriochlorins and their corresponding chlorins and porphyrins against melanoma cancer cells through a photodynamic process. The non-tumoral L929 fibroblast murine cell line was used as the control. The results show that the choice of adequate tetrapyrrolic macrocycle-based PS can be modulated to improve the performance of PDT. [ABSTRACT FROM AUTHOR]

NH2-MIL-125, [Ti8O8(OH)4(bdc-NH2)6] (bdc2-=1,4- benzene dicarboxylate) is a highly porous metal-organic framework (MOF) that has a band gap lying within the ultraviolet region at about 2.6 eV. The band gap may be reduced by a suitable post-synthetic modification of the nanochannels using conventional organic chemistry methods. Here, it is shown that the photocatalytic activity of NH2-MIL-125 in the degradation of methylene blue under visible light is remarkably augmented by post-synthetic modification with acetylacetone followed by CrIII complexation. The latter metal ion extends the absorption from the ultraviolet to the visible light region (band gap 2.21 eV). The photogenerated holes migrate from the MOF's valence band to the CrIII valence band, promoting the separation of holes and electrons and increasing the recombination time. Moreover, it is shown that the MOF's photocatalytic activity is also much improved by doping with Ag nanoparticles, formed in situ by the reduction of Ag+ with the acetylacetonate pendant groups (the resulting MOF band gap is 2.09 eV). Presumably, the Ag nanoparticles are able to accept the MOF's photogenerated electrons, thus avoiding electron-hole recombination. Both, the Cr- and Ag-bearing materials are stable under photocatalytic conditions. These findings open new avenues for improving the photocatalytic activity of MOFs. [ABSTRACT FROM AUTHOR]

The Mini Mental State Examination (MMSE) is the most broadly used cognitive screening instrument in clinical and research contexts. The MMSE was administered to a community-based sample of cognitively healthy adults (n = 850), stratified according to several sociodemographic variables, with a distribution similar to that observed in the Portuguese population. This study aimed to analyze the influence of sociodemographic (age, gender, education level, marital and employment status, geographic region, geographic localization, and residence area) and health variables (subjective memory complaints of the participant and evaluated by the informant, depressive symptoms, and family history of dementia) on the participants’ performance on the MMSE and to establish normative data for the Portuguese population. Education level and age significantly contributed to the prediction of the MMSE scores and explained 26% of its variance. Regarding health variables, only the subjective memory complaints of the participant showed a small contribution (4%) to the variance of the MMSE scores. According to these results, age and education were considered in the development of the normative data of the MMSE for the Portuguese population. [ABSTRACT FROM PUBLISHER]

The term “executive function” has been used to describe several higher-order cognitive processes. This study examined the processing speed, shifting, planning, and verbal fluency of a sample of 50 Portuguese children with developmental dyslexia (DD) and 50 typically developing children (TDC; chronological-age-matched controls) between 8 and 12 years of age to evaluate the children’s executive functioning. Compared to TDC, children with DD revealed significant processing speed, shifting, and verbal fluency deficits. After controlling for differences in the general intellectual ability, significant group differences remained for shifting, verbal fluency and marginally for processing speed. No significant differences in planning ability were observed between the groups. No significant interaction of group, gender, and age was found for any of the executive functions measures studied. Word productivity in both semantic and phonemic verbal fluency tasks decreased significantly over the 60 seconds for both groups. Shifting was the only significant predictor of DD in the binary logistic regression analysis and yielded the highest area under the curve value (receiver operating characteristics curve analysis). Therefore, although these findings highlight the presence of specific executive functions deficits in children with DD, they should not be interpreted as indicative of the presence or absence of this learning disorder. [ABSTRACT FROM AUTHOR]

Calcium manganate Ruddlesden–Popper phases Ca 2 MnO 4–δ were prepared by soft chemistry and treated with acid to extract a part of the calcium ions. Combined structural, morphological and spectroscopic analyses by XRD, SEM/EDX, TEM and Raman revealed an amorphization of the treated surface with a preserved inner crystalline phase in the core of the particles. The inner part of the particles consists of Ca 2 MnO 4–δ and the outer part of hydrated amorphous manganese oxide MnO 2 ·xH 2 O. Although pristine Ca 2 MnO 4–δ is not electrochemically active, electrochemical characterization of the acid-treated powders shows a significant change in capacity that correlates to the amount of extracted calcium. The cycling stability of the Ca 2 + extracted compounds was improved by more than a factor of 10 in comparison to pure MnO 2 ·xH 2 O. The acid-treated Ca 2 MnO 4–δ showed enhanced capacity retention of up to 50% after 70 cycles compared to 4% for bare MnO 2 ·xH 2 O due to its crystalline core. [ABSTRACT FROM AUTHOR]

Following our approach on the use of metalloporphyrins as catalysts and hydrogen peroxide as oxidant in the oxidation of organosulfur compounds (e.g. sulfides, benzothiophenes and dibenzothiophenes), herein the excellent catalytic performance of a homogeneous iron(III) porphyrin complex is demonstrated. Beyond the better results obtained, when compared with those with manganese(III) complexes, the present procedure involves a cleaner approach because ethanol is used as solvent and a co-catalyst is not required. For all the studied substrates (1-10), conversions higher than 95% were achieved with Fe(TF4NMe2PP)Cl (I). More significantly, catalyst (I) is also efficient in the oxidation of a model fuel, constituted by a mixture of benzothiophene (3), 3-methylbenzothiophene (5), 4-methyldibenzothiophene (8) and 4,6-diethyldibenzothiophene (10) in hexane, affording an overall conversion of 84%. [ABSTRACT FROM AUTHOR]

To characterize all hospitalizations held in mainland Portugal (2010–2015) with dementia-related agitation based on International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) coding, and to investigate whether there is a relationship between agitation and hospitalization outcomes. A retrospective observational study was conducted using an administrative dataset containing data from all mainland Portuguese public hospitals. Only hospitalization episodes for patients aged over 65 years who have received a dementia diagnosis ascertained by an ICD-9-CM code of dementia with behavioral disturbance (294.11 and 294.21) and dementia without behavioral disturbance (294.10 and 294.20) were selected. Episodes were further grouped according to the presence of an agitation code. For each episode, demographic data and hospitalization outcomes, including length of stay (LoS), in-hospital mortality, discharge destination and all-cause hospital readmissions, were sourced from the dataset. Comparative analyses were performed and multivariable logistic methods were used to estimate the adjusted associations between agitation (exposure) and outcomes. Overall, 53,156 episodes were selected, of which 6,586 had an agitation code. These were mostly related to male, younger inpatients (mean 81.19 vs. 83.29 years, p < 0.001), had a higher comorbidity burden, stayed longer at the hospital (median 9.00 vs. 8.00 days, p < 0.001) and frequently ended being transferred to another facility with inpatient care. Agitation was shown to independently increase LoS (aOR = 1.385; 95%CI:1.314–1.461), but not the risk of a fatal outcome (aOR = 0.648; 95%CI:0.600–0.700). These results support the importance of detecting and managing agitation early on admission, since its prompt management may prevent lengthy disruptive hospitalizations. [ABSTRACT FROM AUTHOR]

Abstract: Temporal lobe epilepsies are associated with cognitive dysfunctions in memory which are important clues currently used clinically for the lateralization of the epileptic focus in evaluations for epilepsy surgery. Because these lobes also contain the primary auditory cortex, the study of auditory evoked potentials (AEPs) is a candidate, not yet established, complementary method to characterize epilepsy-induced dysfunction. We aimed to establish the clinical usefulness of auditory evoked potentials for the study of pediatric symptomatic temporal lobe epilepsies. A group of 17 patients (ages 4–16) with symptomatic epilepsies undergoing evaluation for epilepsy surgery epilepsy was submitted to auditory evoked potentials using 35-channel scalp EEG recordings. A control group of 10 healthy volunteers was studied with the same protocol. The P100 and mismatch negativity (MMN) potential latencies and normalized amplitudes were studied. We also performed a voxel-based lesion-symptom mapping (VLSM) to determine the anatomical areas associated with changes in the AEPs. Eleven patients had temporal lobe epilepsy, three had frontal lobe epilepsy, and three had occipital lobe epilepsy. Latencies for the P100 were normal in 15/17 and in 11/17 for the MMN, with no consistent correlation with the epilepsy type. The MMN amplitude was abnormal in 7/17 patients, all with temporal lobe epilepsies (sensitivity of 64%). Of these patients, four had a decreased MMN associated with a Heschl's gyrus lesion in the VLSM, and three had an increased MMN associated with hippocampal lesion. No extratemporal epilepsy showed MMN amplitude abnormalities (specificity of 100%). The P100 amplitude was abnormal in 3/17, two with temporal and one with frontal lobe epilepsies. The auditory MMN has a high specificity but a low sensitivity for temporal lobe epilepsy in symptomatic pediatric epilepsies. Amplitude decreases of the MMN are associated with homolateral Heschl's gyrus lesions, and MMN increases with hippocampal lesions. [Copyright &y& Elsevier]

Cognitive decline assessment implies measuring discrepancies between the subject's previous (premorbid) and the current levels of functioning. However, this information is rarely available and clinicians have to infer it by using indirect methods. This article provides an historical overview of the different methods that have been developed for premorbid intelligence estimation, from the first qualitative methods to the most recent quantitative approaches. The discussion sustains that the most valid methods for premorbid intelligence estimation are those that combine current level of the subject's performance and demographic variables in regression formulas. The constant development of premorbid estimation methods with increasing validity is suggestive of the importance that this measure has for psychological assessment. [ABSTRACT FROM AUTHOR]

This study analysed the usefulness of the Wechsler Intelligence Scale for Children-Third Edition in identifying specific cognitive impairments that are linked to developmental dyslexia (DD) and the diagnostic utility of the most common profiles in a sample of 100 Portuguese children (50 dyslexic and 50 normal readers) between the ages of 8 and 12 years. Children with DD exhibited significantly lower scores in the Verbal Comprehension Index (except the Vocabulary subtest), Freedom from Distractibility Index (FDI) and Processing Speed Index subtests, with larger effect sizes than normal readers in Information, Arithmetic and Digit Span. The Verbal-Performance IQs discrepancies, Bannatyne pattern and the presence of FDI; Arithmetic, Coding, Information and Digit Span subtests (ACID) and Symbol Search, Coding, Arithmetic and Digit Span subtests (SCAD) profiles (full or partial) in the lowest subtests revealed a low diagnostic utility. However, the receiver operating characteristic curve and the optimal cut-off score analyses of the composite ACID; FDI and SCAD profiles scores showed moderate accuracy in correctly discriminating dyslexic readers from normal ones. These results suggested that in the context of a comprehensive assessment, the Wechsler Intelligence Scale for Children-Third Edition provides some useful information about the presence of specific cognitive disabilities in DD. Copyright © 2013 John Wiley & Sons, Ltd. Practitioner Points Children with developmental dyslexia revealed significant deficits in the Wechsler Intelligence Scale for Children-Third Edition subtests that rely on verbal abilities, processing speed and working memory., The composite Arithmetic, Coding, Information and Digit Span subtests (ACID); Freedom from Distractibility Index and Symbol Search, Coding, Arithmetic and Digit Span subtests (SCAD) profile scores showed moderate accuracy in correctly discriminating dyslexics from normal readers., Wechsler Intelligence Scale for Children-Third Edition may provide some useful information about the presence of specific cognitive disabilities in developmental dyslexia. [ABSTRACT FROM AUTHOR]

Abstract: Panayiotopoulos syndrome (PS) is a common epilepsy syndrome associated with rare clinical seizures and unknown localization of the epileptogenic area. Despite findings of normal development in patients with PS, recent neuropsychological studies point to subtle and diverse cognitive impairments. No well-outlined hypothesis about the localization of the brain dysfunction responsible for these impairments has been proposed. We further explored the cognitive dysfunctions in PS and made inferences on the most likely anatomical localization of brain impairment. A group of 19 patients (aged 6–12) with PS was rated according to spike activity and lateralization. The patients were submitted to a neuropsychological evaluation to assess general intelligence, memory, language, visual–perceptual abilities, attention, and executive functions. Using 35-channel scalp EEG recordings, the N170 face-evoked event-related potential (ERP) was obtained to assess the functional integrity of the ventral pathway. All patients with PS showed normal IQ but subtle and consistent neurocognitive impairments. Namely, we found abnormalities in the copy task of the Rey–Osterrieth Complex Figure and in the Narrative Memory Test. There was no correlation between neuropsychological impairments with spike activity and hemispheric spike lateralization. The N170 ERP was normal in all patients except for one. Our neuropsychological findings demonstrate impairments in visual–perceptual abilities and in semantic processing. These findings, paired with the absence of occipital lobe dysfunction in all neuropsychological studies of PS performed to this date, support the existence of parietal lobe dysfunction. [Copyright &y& Elsevier]

The term "executive function" has been used to describe several higher-order cognitive processes. This study examined the processing speed, shifting, planning, and verbal fluency of a sample of 50 Portuguese children with developmental dyslexia (DD) and 50 typically developing children (TDC; chronological-age-matched controls) between 8 and 12 years of age to evaluate the children's executive functioning. Compared to TDC, children with DD revealed significant processing speed, shifting, and verbal fluency deficits. After controlling for differences in the general intellectual ability, significant group differences remained for shifting, verbal fluency and marginally for processing speed. No significant differences in planning ability were observed between the groups. No significant interaction of group, gender, and age was found for any of the executive functions measures studied. Word productivity in both semantic and phonemic verbal fluency tasks decreased significantly over the 60 seconds for both groups. Shifting was the only significant predictor of DD in the binary logistic regression analysis and yielded the highest area under the curve value (receiver operating characteristics curve analysis). Therefore, although these findings highlight the presence of specific executive functions deficits in children with DD, they should not be interpreted as indicative of the presence or absence of this learning disorder. [ABSTRACT FROM AUTHOR]

Highlights: [•] Study of cognitive and psychomotor predictors of unsafe driving in older adults. [•] The best predictors of the Senior Drivers Battery were derived from reaction time tasks. [•] Additional tests of visuospatial and executive abilities with higher accuracy were identified. [•] Certain tests may be included in predictor models of driving fitness in older adults. [ABSTRACT FROM AUTHOR]

Metalloporphyrins (MPs) are known to catalyze in vitro a broad range of cytochrome P450-mediated reactions occurring in vivo. Most of the biomimetic research using MPs in oxidative catalysis has been directed towards the oxidation of organic compounds presenting significant reactivity features in one functional group. Much less effort has been made to imitate the oxidation of more complex molecules, with a range of functionalities, such as drugs or other xenobiotics. By varying the structure of the porphyrin, the metal ion, the oxidant, and the reaction conditions, it is possible to modulate the regioselectivity of the oxidation reactions. Recently, and along with studies on the synthesis and reactivity of porphyrins, chlorins, and phthalocyanines, our group was able to develop an interesting line of research in the field of biomimetic oxidation of organic compounds using environmentally benign hydrogen peroxide as oxidant and Mn(III) or Fe(III) porphyrin complexes as catalysts. The more up to date results obtained in such work are reviewed here. [ABSTRACT FROM AUTHOR]

Verbal fluency tests are sensitive to different neuropsychological functions used in assessing the integrity of the frontal and temporal lobes. In this study, 120 healthy children (aged 7 to 10 years) were examined through a semantic and a phonemic verbal fluency test. The results of exploratory factor analysis, confirmatory factor analysis and correlation analysis seem to indicate that these two verbal fluency tests depend on different neurocognitive functions. The number of words produced in the phonemic task was significantly lower than the semantic task, indicating that is cognitively more complex. No gender differences were found, but a significant effect was observed for children's age, showing the sensitivity of these verbal fluency tests to neurodevelopmental processes. The analyze of performance over the 60 seconds showed a significant production of words in the first 15 seconds and decrease over the remaining 45 seconds. [ABSTRACT FROM AUTHOR]

Cognitive screening tests are well-established tools for detecting cognitive impairment, but concerns regarding the influence of premorbid intelligence on patient’s performance and cognitive status classification remain. Risk of inaccurate assessment especially affects the elders with high or low premorbid intelligence (who are more likely to be misclassified). The present study examines the influence of premorbid intelligence assessed by the TeLPI (an irregular words reading test) on 2 cognitive screening tests, the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA), in healthy participants and patients with cognitive impairments (mild cognitive impairment and Alzheimer disease). Results show that premorbid IQ influences the MMSE and the MoCA scores in both the groups, predicting variance from 8.4% to 33.2%, according to test and group analyzed. Hence, we propose that whenever the MMSE or the MoCA is used, premorbid IQ evaluation should also be considered to ensure correct interpretation and classification. [ABSTRACT FROM PUBLISHER]

The Montreal Cognitive Assessment (MoCA) is a brief instrument developed for the screening of milder forms of cognitive impairment, having surpassed the well-known limitations of the MMSE. The aim of the present study was to validate the MoCA as well as its short version, which was proposed by the NINDS-CSN VCI Harmonization Standards for screening Vascular Dementia (VaD) patients. The results, based on a homogeneous sample of 34 VaD patients, indicate that the MoCA is a psychometrically valid and reliable instrument for cognitive screening in VaD patients, showing excellent discriminant validity. Both the full and short versions of the MoCA had excellent diagnostic accuracy in discriminating VaD patients, exhibiting an area under curve (AUC) higher than the MMSE [AUC(MoCA full version) = .950; 95% IC = .868-.988; AUC(MoCA short version) = .936; 95% IC = .849-.981; AUC(MMSE) = .860; 95% IC = .754-.932]. With a cutoff below 17 on the MoCA full version and 8 on the short version, the results for sensitivity, specificity, positive and negative predictive values, and classification accuracy were superior compared to the MMSE. In conclusion, both versions of the MoCA are valid, reliable, sensitive and accurate screening instruments for VaD patients. [ABSTRACT FROM AUTHOR]

Abstract: Considerable research has shown that neuropsychological tests are predictive of real-world driving ability. The Mini-Mental State Examination (MMSE) is a brief cognitive test that has been commonly used in the assessment of older drivers. However, this test has inherent problems that limit its validity to evaluate cognitive abilities related to driving and to screen for driving impairments in non-demented people. Therefore, it is useful to test new screening instruments that may predict potential unsafe drivers who require an in-depth neuropsychological assessment in a specialised centre. To date, the utility of the Addenbrooke''s Cognitive Examination Revised (ACE-R) as an indicator of driving ability has not been established. In the current study, fifty older drivers (mean age=73.1years) who were referred for a psychological assessment, the protocol of which included the ACE-R, underwent an on-road driving test. Using linear discriminant analyses, the results highlighted the higher classification accuracy of the ACE-R compared to the MMSE score, particularly for detecting unsafe drivers. Measures of visuospatial and executive functions, which are not incorporated in the MMSE score, had an incremental value in the prediction of driving ability. This emerging brief cognitive test may warrant additional study for use in the fitness to drive assessment of older adults. [Copyright &y& Elsevier]

Abstract: Type 2 diabetes mellitus has emerged as a major non-communicable chronic diseases in many countries. The importance of exercise in the prevention and management of this disease is evident. This paper briefly reviews the effects of combining aerobic and resistance exercises on glycemic control, and details the training and characteristics of various interventions in adults with type 2 diabetes mellitus. Literature searches were performed using electronic databases between the 1st of January 1950 and the 15th of September 2011. Of the 403 articles retrieved, 28 studies met our inclusion criteria. Combined exercise protocols seem to improve glycemic control to a greater extent than isolated forms of exercise. Nevertheless, length, duration, intensity, mode, number of exercises, sets and repetitions varied markedly among studies. Supervised training sessions, recommended structured exercises, and splitting aerobic and resistance training in separate sessions may be relevant for best results. Future studies should analyze the effects of different aerobic and resistance training modes, different training and progression methods, and whether one type of exercise is optimal, as these issues are likely to convey greater knowledge on type 2 diabetes mellitus management through combined exercise. [Copyright &y& Elsevier]

The Montreal Cognitive Assessment (MoCA) is a brief instrument developed for the screening of milder forms of cognitive impairment, having surpassed the well-known limitations of the Mini-Mental State Examination (MMSE). The aim of the present study was to validate the MoCA as a cognitive screening test for behavioral-variant frontotemporal dementia (bv-FTD) by examining its psychometric properties and diagnostic accuracy. Three matched subgroups of participants were considered: bv-FTD (n = 50), Alzheimer disease (n = 50), and a control group of healthy adults (n = 50). Compared with the MMSE, the MoCA demonstrated consistently superior psychometric properties and discriminant capacity, providing comprehensive information about the patients’ cognitive profiles. The diagnostic accuracy of MoCA for bv-FTD was extremely high (area under the curve AUC [MoCA] = 0.934, 95% confidence interval [CI] = 0.866-.974; AUC [MMSE] = 0.772, 95% CI = 0.677-0.850). With a cutoff below 17 points, the MoCA results for sensitivity, specificity, positive predictive value, negative predictive value, and classification accuracy were significantly superior to those of the MMSE. The MoCA is a sensitive and accurate instrument for screening the patients with bv-FTD and represents a better option than the MMSE. [ABSTRACT FROM AUTHOR]

The Montreal Cognitive Assessment (MoCA) is a brief cognitive instrument for screening milder forms of cognitive impairment. The present study aimed to analyze the influence of sociodemographic (age, gender, educational level, marital and employment status, geographic region, geographic localization, and residence area) and health variables (subjective memory complaints of the participant and evaluated by the informant, depressive symptoms, and family history of dementia) on the participants' performance on the MoCA. The investigation was carried out in a Portuguese community-based sample of 650 cognitively healthy adults, who were representative of the distribution observed in the Portuguese population. Educational level and age significantly contributed to the prediction of the MoCA scores, explaining 49% of the variance. Regarding health variables, only the subjective memory complaints of the participant showed a small contribution (9%) to the variance on the MoCA scores. This study contributes a useful approach to understanding MoCA performance, stressing the great impact of education and age on scores. [ABSTRACT FROM PUBLISHER]

The Montreal Cognitive Assessment (MoCA) is a brief instrument developed for the screening of milder forms of cognitive impairment. The present study aims to assess the construct related validity of the MoCA through the establishment of the factorial, convergent, and discriminant related validities, and the reliability of data. In a Portuguese sample of 830 participants, several models were tested using Confirmatory Factor Analysis. Although all tested models showed a good fit, the six-factor model based on the conceptual model proposed by the MoCA's authors showed a significantly better fit. The results allowed us to establish the factorial, convergent, and discriminant validity of this six-dimensional structure. An overall psychometric adequacy of the items, and a good reliability were also found. This study contributes to overcome an important gap in the construct related validity of this instrument. The present findings corroborate the six-dimensional structure of the MoCA and provide good evidence of the construct related validity. The MoCA has proved to be an appropriate measure for cognitive screening taking into account different cognitive domains, which will enable clinicians and researchers to use this test and its six latent dimensions to achieve a better understanding of the individuals’ cognitive profile. (JINS, 2012, 18, 242–250) [ABSTRACT FROM PUBLISHER]

Information regarding cognitive abilities in earlier stages of life is essential to ascertain if and to what extent these may have declined. When unavailable, clinicians rely on estimate methods. One of the contemporary methods used worldwide combines performance on irregular word reading test with demographics since it has shown to provide reliable estimates of premorbid ability. Hence, a reading test portuguese irregular word reading test (TeLPI) was developed, filling an important gap in the neuropsychological evaluation of Portuguese speakers. Using 46 irregular, infrequent Portuguese words, TeLPI was validated against Wechsler Adult Intelligence Scale (WAIS)-III (N = 124), and regression-based equations were determined to estimate premorbid IQ considering TeLPI scores and demographic variables. TeLPI scores accounted for 63% of the variance of WAIS-III Full-Scale IQ, 62% of Verbal IQ, and 47% of Performance IQ and thus were considered valid for premorbid intelligence estimation. [ABSTRACT FROM PUBLISHER]

Abstract: Effects toward electrocatalytic activity for glycerol oxidation of the modification of carbon supported Pd and Pt-based nanomaterials by bismuth were evaluated in alkaline medium. Pd/C, Pd0.9Bi0.1/C, Pt/C, Pt0.9Bi0.1/C and Pd0.45Pt0.45Bi0.1/C catalysts were synthesized by a colloidal route, and physical and electrochemical methods were used to characterize the structure and the surface of the catalysts (TEM, HRTEM, EDX, XRD, ICP-OES and XPS). It was shown that only a few amount of bismuth was deposited on the Pt and/or Pd surface, and that no alloy was formed between bismuth and the other metals. The onset potential of glycerol oxidation is ca. 0.15V lower on Pt/C than on Pd/C. However, Pt-free Pd0.9Bi0.1/C catalyst presented the same catalytic activity than platinum catalyst. The Pt0.9Bi0.1/C led reaching a higher catalytic activity by shifting the oxidation onset potential by ca. 0.2V toward lower potentials compared with the Pt/C catalyst. But, the replacing of half of the platinum atoms by palladium atoms in the Pd0.45Pt0.45Bi0.1/C material allowed achieving the same catalytic activity as with Pt0.9Bi0.1/C. Electrochemical experiments combined with in situ infrared spectroscopy measurements have shown that glycerol electrooxidation mechanism is independent on the catalyst, but dependent on the electrode potential. Chronoamperometry experiments combined with HPLC measurements showed that the main reaction products were glycerate, dihydroxyacetone and tartronate at low potentials, and that the increase of the electrode potential led to the formation of mesoxalate. For potential higher than 0.8V vs RHE, the C–C bond cleavage occurred and oxalate and formiate were detected. [Copyright &y& Elsevier]

Abstract: The oxidation of styrene and derivatives with H2O2 catalyzed by manganese porphyrins in acetonitrile is described. The effect of the imidazolium substituent on the catalytic efficiency has been also considered. The thermodynamic analysis has indicated that enthalpy rules styrene oxidation when catalysts Mn(Porph)-1 and Mn(Porph)-2 are used whereas the entropy is the driven force for Mn(Porph)-3 and Mn(Porph)-4 catalyzed reactions. Interestingly, an enthalpy–entropy compensation phenomenon is observed when comparing the thermodynamic results obtained for catalysts Mn(Porph)-3 and Mn(Porph)-4. Hammett plots for the studied manganese porphyrins provided small ρ-values, and this is typical for multi-step reactions, indicating that there is no significant charge separation in the transition state. For Mn(Porph)-1 and Mn(Porph)-2 the formation of multiple active species can be put forward whereas for Mn(Porph)-3 and Mn(Porph)-4 a concerted-type mechanism, via metalloxetane intermediate, fits well with the values obtained for those catalysts. The imidazolium-based catalysts have shown to be efficient catalysts in styrene and derivatives oxidation with hydrogen peroxide. [Copyright &y& Elsevier]

Context: The philosophy of care Humanitude emphasizes the value of relational connection and the human factor (Simões, Rodrigues e Salgueiro, 2008). We focus on the important contribution of the Gineste and Marescotti Humanitude method of care published by Gineste and Pellissier (2007). Objectives: to understand the importance that nurses attach to the Humanitude philosophy of care based on Method and Humanitude by Gineste and Marescotti; to identify the extent to which nurses report that they apply the principles of the Method of Gineste and Marescotti in practice. Methods: Descriptive study developed from data collected from a sample of 160 nurses, the population covered by the Regional Section of the Center of the Order of Nurses and who voluntarily answered the survey online. The instrument for data collection, developed and validated, consists of 28 items in the dimensions "approach tuning" and "proactive consolidation". Results: The nurses interviewed stated that consistent approach procedures (90.31%) and proactive consolidation (85.47%) were important or very important. Only 2.21% downplayed the Method. In care practice, nurses said that they often or always applied the principles of tuning approach (83.05%) and proactive consolidation (69.69%). Conclusions: Using a strategy of observation in context, we intend to verify in future research the consistency between the views expressed and actual practice. [ABSTRACT FROM AUTHOR]

Abstract: The biomimetic oxidation of caffeine with hydrogen peroxide using metalloporphyrins as catalysts, which are known to be good biomimetic models of cytochrome P450 enzymes, is investigated. The two manganese porphyrins tested, chloro[5,10,15,20-tetrakis(2,6-dichlorophenyl)porphyrinato]manganese(III), [Mn(TDCPP)Cl], and chloro [5,10,15,20-tetrakis(pentafluorophenyl)porphyrinato]manganese(III), [Mn(TPFPP)Cl], afford high conversions of caffeine for all substrate/catalyst molar ratios. Selectivity was found to be dependent on the catalyst employed, and a new spiro racemic compound is described and fully characterized in the solid state from X-ray diffraction studies. [Copyright &y& Elsevier]

Abstract: In the past few years, borohydrides have gathered a lot of attention as an energy carrier for fuel cell application. Numerous investigations on both hydrogen generation and direct oxidation of NaBH4 have been published. Nonetheless, in our knowledge, only a few catalysts are capable to completely perform the direct oxidation of NaBH4 at low potentials without hydrogen evolution. In this work, carbon supported Pd1−x Bi x /C and Pt1−x Bi x /C nanocatalysts were synthesized by a “water in oil” microemulsion method. The influence of surface modifications of Pt and Pd by Bi on the electrooxidation of sodium borohydride in alkaline media was evaluated. Physical and electrochemical methods were applied to characterize the structure and surface of the synthesized catalysts. It was verified that bismuth is present at the surface of the bimetallic catalysts and that hydrogen adsorption/desorption reactions are strongly limited on Pt and Pd surfaces with high bismuth coverage. Although the onset potential for NaBH4 oxidation on Pd x Bi1−x /C catalysts is ca. 0.2V higher than that for Pd/C, the presence of bismuth on palladium surface influences the reaction mechanism, limiting hydrogen evolution and oxidation in the case of Pd0.8Bi0.2 catalyst. On Pt0.9Bi0.1 catalyst the onset potential remains unchanged comparing to Pt/C and negligible hydrogen evolution was observed in the whole potential range where the catalyst is active. The number of exchanged electrons was calculated using the Koutecky–Levich equation and it was found that for Pt0.9Bi0.1 catalyst, ca. 8 electrons are exchanged per BH4 − ion at low potentials. The presented results are remarkable evidencing that NaBH4 can be directly oxidized at low potentials with high energy efficiency. [Copyright &y& Elsevier]

The Montreal Cognitive Assessment (MoCA) is a cognitive screening instrument created with the purpose of overcoming some of the insufficiencies of the Mini-Mental State Examination (MMSE). The MoCA evaluates more cognitive areas and is comprised of more complex tasks as compared with the MMSE, which makes it a more sensitive instrument in the detection of Mild Cognitive Impairment (MCI), a state that often progresses to dementia. In this study we performed an analysis of the psychometric and diagnostic properties of the Portuguese experimental version of the MoCA in a clinical sample of 212 subjects with MCI and several dementia subtypes in a memory clinic setting. Additionally, we performed a Confirmatory Factor Analysis (CFA) to assess the MoCA’s latent factorial structure. In a clinical population, the MoCA is a valid and reliable instrument with good psychometric properties, revealing high sensitivity in identifying MCI and dementia patients who generally score within the normal range on the MMSE. By using the parcels method, CFA results showed very good/excellent adjustment indexes. The practical implications of this CFA study allow us to propose a two factor model factorial structure for the MoCA: a first factor designated MEMORY, which includes memory, language and orientation subtests (the latter being closely correlated with the former), and a second factor designated ATTENTION/EXECUTIVE FUNCTIONS, comprised of attention, executive functions and visuospacial abilities tasks. [ABSTRACT FROM AUTHOR]

Abstract: Carbon supported Pd, Pt, Au and bimetallic PdAu and PdNi nano-catalysts with different compositions were synthesized. Their catalytic activity toward glycerol electro-oxidation was evaluated in alkaline medium. Physical and electrochemical methods where used to characterize the structure and the surface of the catalysts. It was shown that the Pd x Au1−x /C catalysts were alloys, which present an increase of crystallite (XRD) and particle (TEM) sizes with increasing Au atomic fraction. Their surfaces were palladium rich whatever the Pd atomic ratio. The structure of the Pd0.5Ni0.5/C catalyst is much more difficult to understand, but it seems to be composed of a palladium phase in interaction with a Ni(OH)2 phase. The onset potential of glycerol oxidation is ca. 0.15V lower on Pt/C than on Pd/C and Au/C. All Pd x Me1−x /C catalysts presented lower onset potential than monometallic Au/C and Pd/C ones, but higher than Pt/C. For bimetallic catalysts, the order of activity at low potentials is: Pd0.3Au0.7/C>Pd0.5Au0.5/C>Pd0.5Ni0.5/C. Electrochemical experiments and in situ infrared spectroscopy measurements have shown that glycerol electro-oxidation mechanism is dependent on the catalyst, leading to different reaction products. Adsorbed CO species are detected on monometallic Pt and on Pd rich catalysts, but not on Au and Pd0.3Au0.7 catalysts, indicating that they are not able to break the C–C bond. The formation of hydroxypyruvate ion, which is a costly chemical product, is detected on pure gold catalyst. [Copyright &y& Elsevier]