Herding behaviour and sentiment: Evidence in a small European market

AbstractThis work studies herding behaviour in a small European market, by analysing the stocks that constituted the Portuguese stock PSI-20 index, for the period between 2003 and 2011. The two different approaches used to measure herding intensity led to different results, suggesting that measurements of the herding phenomenon are sensitive to the method used. Consequently, there is a need for further research into the methodology used to test this phenomenon. Additionally, the study analyses the relationship between herd behaviour and investor sentiment, an area that has been little explored. In applying causality tests to the impact of sentiment on herd behaviour, only weak evidence is found that sentiment influences herding

Acoustics reflex abnormalities in auditory processing disorder

Introduction: The acoustic reflex threshold is defined as the lowest sound intensity capable of starting the middle ear protection mechanism due to intense sounds (Metz, 1952; Jerger, 1970), being necessary the structural and functional integrity of the periferic and central auditory system. These structures are also responsable for the central processing of auditory information. Aim: We intend to verify whether acoustic reflex abnormalities can also appear in auditory processing (AP) disorders, resulting in symptoms related to speech and language disorders. Study design: Prospective randomized. Material and method: Data were analyzed from one hundred AP assessments, using Pereira (1997) method. Patients, male and female, with ages ranging from 07 to 18 years, had normal hearing thresholds and normal tympanograms patterns. The difference between the acoustic reflex and hearing thresholds defined the acoustic reflex level (ARL), considered normal between 70-90dB and altered when above of this range or when absent in one or more frequencies (Carvallo, 1996; 1997; Metz, 1952). Results: Disorders of AP were found in 97% of the patients. In this group, 62% showed ARL abnormalities, being statistically significant. Furthermore, patients with AP disorders showed ARL alterations, more frequently on severe degree disorders, on patients with combined auditory gnosis impairments and on patients with more than one auditory ability altered. Conclusion: Patients with acoustic reflex alterations and normal audiometry should perform the AP assessment, as these symptoms could unmask pathologies of the central nervous system.Introdução: O limiar do reflexo acústico corresponde à menor intensidade de um som capaz de desencadear o mecanismo de proteção da orelha média frente a sons intensos (Metz, 1952; Jerger, 1970), sendo necessária a integridade estrutural e funcional do sistema auditivo periférico e central em nível de tronco encefálico. Algumas dessas estruturas são também responsáveis pelo processamento central da informação auditiva. Objetivo: Procuramos verificar se alterações do reflexo acústico também estariam presentes na Desordem do Processamento Auditivo Central (DPA), levando a queixas relacionadas aos distúrbios da comunicação. Forma de estudo: Prospectivo randomizado. Material e método: Foram analisados cem protocolos de avaliações do Processamento Auditivo Central (PAC), realizadas segundo Pereira (1997), de indivíduos dos sexos masculino e feminino, de 7 a 18 anos, com limiares de audibilidade normais e timpanograma tipo A. A diferença entre os limiares do reflexo acústico e os de audibilidade forneceu os níveis de reflexos acústicos (NRA), considerados normais entre 70-90dB e alterados quando acima deste intervalo ou quando ocorreu ausência em uma ou mais freqüências (Carvallo, 1996; 1997; Metz, 1952). Resultados: Das crianças avaliadas 97% apresentaram algum tipo de DPA. Destas, 62% tiveram NRA alterados, numa relação estatisticamente significante. Além disso, pacientes com DPA mostraram NRA alterados, mais freqüentemente, nas desordens de grau severo, naquelas com prejuízos gnósicos auditivos combinados e naquelas com mais de uma habilidade auditiva alterada. Conclusão: Assim, indivíduos com alterações no reflexo acústico e sem alterações audiométricas devem submeter-se a provas de PAC, já que esses sintomas podem ser manifestações patológicas do sistema nervoso central.UNIFESP-EPM OtorrinolaringologiaUNIFESP-EPMUNIFESP, EPM, OtorrinolaringologiaUNIFESP, EPMSciEL

Enhanced enzyme reuse through the bioconjugation of L-asparaginase and silica-based supported ionic liquid-like phase materials

L-asparaginase (ASNase) is an amidohydrolase that can be used as a biopharmaceutical, as an agent for acrylamide reduction, and as an active molecule for L-asparagine detection. However, its free form displays some limitations, such as the enzyme’s single use and low stability. Hence, immobilization is one of the most effective tools for enzyme recovery and reuse. Silica is a promising material due to its low-cost, biological compatibility, and tunable physicochemical characteristics if properly functionalized. Ionic liquids (ILs) are designer compounds that allow the tailoring of their physicochemical properties for a given task. If properly designed, bioconjugates combine the features of the selected ILs with those of the support used, enabling the simple recovery and reuse of the enzyme. In this work, silica-based supported ionic liquid-like phase (SSILLP) materials with quaternary ammoniums and chloride as the counterion were studied as novel supports for ASNase immobilization since it has been reported that ammonium ILs have beneficial effects on enzyme stability. SSILLP materials were characterized by elemental analysis and zeta potential. The immobilization process was studied and the pH effect, enzyme/support ratio, and contact time were optimized regarding the ASNase enzymatic activity. ASNase–SSILLP bioconjugates were characterized by ATR-FTIR. The bioconjugates displayed promising potential since [Si][N3444]Cl, [Si][N3666]Cl, and [Si][N3888]Cl recovered more than 92% of the initial ASNase activity under the optimized immobilization conditions (pH 8, 6 × 10−3 mg of ASNase per mg of SSILLP material, and 60 min). The ASNase–SSILLP bioconjugates showed more enhanced enzyme reuse than reported for other materials and immobilization methods, allowing five cycles of reaction while keeping more than 75% of the initial immobilized ASNase activity. According to molecular docking studies, the main interactions established between ASNase and SSILLP materials correspond to hydrophobic interactions. Overall, it is here demonstrated that SSILLP materials are efficient supports for ASNase, paving the way for their use in the pharmaceutical and food industries.publishe

Effect of Genetic Material and Rotation on the Properties of Charcoal

This study aimed to evaluate chemical properties and yield of charcoal from two Eucalyptus urophylla clones considering the first and second rotation of the wood. The study was carried out with material from Arcelor Mittal Jequitinhonha, with a mean age of 61.5 months. The values of fixed carbon, volatile materials, ash content, higher calorific value, gravimetric yield, liquid yield and gas yield were determined. The data were analyzed statistically by Analysis of Variance (ANOVA) and significant differences were compared by the Tukey test (p <0.05). The results showed significant differences for the fixed carbon contents (67% and 70.5%) and volatile materials (32% and 29%) of clones AEC 0182 and AEC 0296, respectively. The analysis of the results showed that both the first and second rotation woods have satisfactory characteristics for charcoal production and are not influenced by the effect of the rotations

Bullying of individuals with cleft lip and palate frequency and preventive procedures

Purpose: The purpose of this study was to verify the prevalence of bullying among children and adolescents, the consequences on the social development and educational process, evaluating the public policies for prevention or punishment of this negative behavior. Methods: The study group comprised 121 patients with cleft lip and palate in the process of rehabilitation in a single center from both sexes with age varying from 6 to 35 years. The control group comprised 121 siblings of these patients born without cleft lip and palate. A questionnaire with objective questions on bullying and its consequences was answered by one of the parents or tutors. Preventive procedures were discussed with the parents. The prevalence of bullying was calculated for each group. Intergroup comparisons were performed using Chi-square and Fisher exact tests (p<0.05). Results: Bullying was reported as a frequent occurrence in the group of individuals with cleft lip and palate (50.4%). A higher frequency of bullying against individuals with CLP was found compared to the group of siblings without CLP (22.3%) (p<0.01). The most common type of bullying was oral offense (78.7%) followed by physical with oral offense (19.7%). The school was the most frequent place of bullying occurrence (86.9%). Most of the parents/tutor reported the desire for educational procedures and public policies to prevent this type of aggression. Conclusions: Bullying was more frequent among individuals with cleft lip and palate in comparison with noncleft individuals. Public policies should be implemented for educating and preventing this violence against human being

Biodiesel derived from microalgae: advances and perspectives

Microalgae are a promising source of raw material for biodiesel production. This review discusses the latest developments related to the application of microalgae biomass for biodiesel production. Characterization of fatty acid of microalgae and comparisons with other sources of raw materials and processes are presented. Furthermore, technological perspectives and approaches for growing microalgae in photobioreactors, microalgal oil extraction techniques, and procedures for synthesizing biodiesel are reviewed

Design of nanostructures, obtained from assembling of α-lactalbumin and lysozyme upon heat treatment and selective environmental conditions

Protein assembly into supramolecular structures (e.g. aggregates, fibrils and nanotubes) is a widespread phenomenon in biological sciences. Nowadays, it is well documented that the amphiphilic properties of proteins is a driving force to their self-assembling into innovative micro- and nanostructures of high interest in the food and pharmaceutical fields. Formation of such structures is strongly dependent on physicochemical conditions and protein conformation. In this study, bio-based nanostructures were produced from assembly of hen egg white lysozyme (Lys) and bovine α-lactalbumin (α-La) – i.e. two homologous globular proteins with opposite charge), under various processing conditions: heating treatment (55 °C and 75 °C), holding time (25 and 35 min) and pH (3 and 11). The nano-scale structures prepared by solubilization of 2 mg mL-1 of Lys and α-La powders in water, at a molar ratio of 1:0.54, were characterized via dynamic light scattering (in terms of particle size, polydispersity and zeta potential), and further analyzed by transmission electron microscopy (TEM). Smaller sized particles (75 nm) and low podydispersity values (0.24) were produced at pH 11 after heating at 75 °C for 25 min, whereas at pH 3 (and similar conditions) the average mean particle size was ca. 402 nm with polydispersity of 0.45. The nanostructure stability was also assessed; higher stability was obtained at pH 11 than 3, with zeta potentials of -35 and +27 mV, respectively, by 60 d. The nanostructure entities prepared at pH 11 were shown by TEM to possess a well defined spherical shape. Protein assembly mechanisms and intermolecular interactions involved appear to be controlled by the environmental conditions applied; therefore, an understanding of the quantitative effects of these conditions are crucial for rational design of new protein assemblies with tailor-made functionalities