The Impact of Motor Learning on Motor Behavior and Cortical Dynamics in a Complex Stressful Social Environment

An economy of effort is a core characteristic of highly skilled motor performance often described as being effortless or automatic. Electroencephalographic (EEG) evaluation of cortical activity in elite performers has consistently revealed a reduction in extraneous associative cortical activity and an enhancement of task-relevant cortical processes. However, this has only been demonstrated under what are essentially practice-like conditions. Recently it has been shown that cerebral cortical activity becomes less efficient when performance occurs in a stressful, complex social environment. This dissertation examines the impact of motor skill training or practice on the EEG cortical dynamics that underlie performance in a stressful, complex social environment. Sixteen ROTC cadets participated in head-to-head pistol shooting competitions before and after completing nine sessions of skill training over three weeks. Spectral power increased in the theta frequency band and decreased in the low alpha frequency band after skill training. EEG Coherence increased in the left frontal region and decreased in the left temporal region after the practice intervention. These suggest a refinement of cerebral cortical dynamics with a reduction of task extraneous processing in the left frontal region and an enhancement of task related processing in the left temporal region consistent with the skill level reached by participants. Partitioning performance into ‘best’ and ‘worst’ based on shot score revealed that deliberate practice appears to optimize cerebral cortical activity of ‘best’ performances which are accompanied by a reduction in task-specific processes reflected by increased high-alpha power, while ‘worst’ performances are characterized by an inappropriate reduction in task-specific processing resulting in a loss of focus reflected by higher high-alpha power after training when compared to ‘best’ performances. Together, these studies demonstrate the power of experience afforded by practice, as a controllable factor, to promote resilience of cerebral cortical efficiency in complex environments.

Impact of dental caries on quality of life of adolescents according to access to oral health services: a cross sectional study

Aim: This study presents the prevalence of dental caries and its relation to the quality of life of adolescents according to the access to dental health services. Methods: Two hundred and fifty-six adolescents between 15 and 19 years of age participated in the study; they were all enrolled in public schools in a countryside municipality of the São Paulo State. Data related to dental caries were evaluated by the DMFT Index, and OHIP-14 was used for evaluating the quality of life. Mann Whitney and Spearmann correlation tests were also used (p<0.05). Results: A DMFT of 3.09 (±3.30) was found with a higher prevalence among the adolescents who used public dental services (3.43±3.34) compared with those who used private services (2.94±3.28). A statistically significant relationship between the decay component of DMFT with physical pain (0.020), physical disability (0.002) and quality of life (0.017) was verified. Conclusions: A low prevalence of dental caries was observed, and it was higher in adolescents who used public oral health services rather than private ones, evidencing the low influence of oral health on the quality of life of the participants.

Impact of a fall prevention program in the Internal Medicine wards of a tertiary care university hospital

Objective: To determine whether a falls prevention program reduces the incidence of falls within a hospital. Materials and methods: Each patient admitted to the Internal Medicine ward was classiied into a risk category (high, medium, low) according to the scale of J.H. Downton, and then various general and speciic measures were applied by risk group. Interventions included appointments, teaching materials, and training of medical staff and family. Furthermore, a registration system was developed that allowed adverse event fe edback to the program and identiicat ion of the causes of the fall. The SPSS version 20.0 was used for the data analysis. Descriptive analysis was used for quantitative variables, and qualitative variables were expressed as proportions. To compare the rate of pre- and post-program implementation falls, x 2 was used, with a  = 0.05 determining a signiicant statistical value. Results: Since the implementation of the program, the rate of falls per 1000 days/patient decreased from 1.9 in 2007 to 0.67 in the period 2008-2013, representing a decrease of the rate of falls of up to 70%, with a statistically signiicant difference (P=.02). Conclusions: The implementation of a falls prevention program is an effective tool and reduces the rate and complications associated with them.

Equity-focused health impact assessment of Portuguese tobacco control legislation

The World Health Organization recommend the Equity-Focused Health Impact Assessment (HIA) as a means to assess the impact of social and economic policies on the health of populations, and acknowledges their contribution to health inequality. We describe the application of the Equity-focusedImpact Assessment methodology on the Portuguese law on Smoking Prevention and Tobacco Control (Law No. 37/2007). A rapid assessment was carried out to issue recommendations which could be incorporated into the law during a revision in 2014. Quantitative (consumption and health status indicators; equity analysis) and qualitative (Focus Group) approaches were taken to evaluate the impact of the law and formulate recommendations. Young people, men and women of low socioeconomic status, and pregnant women were identified as requiring specific and appropriate interventions to prevent smoking and support smoking cessation.

Tradicional ou Low Cost?

Sendo o sector do transporte aéreo considerado dos mais importantes no crescimento económico nacional e internacional, torna-se necessário comparar os vários tipos de consumidores, os seus comportamentos, e o que os leva a decidir escolher companhias aéreas low cost em detrimento de companhias aéreas tradicionais. Desta forma, este estudo propõe investigar se o preço, associado à satisfação do consumidor, tem impacto no momento de decisão, em detrimento de outros atributos como sejam a reputação da marca ou outras valências do produto oferecido. Assim, em função da satisfação, serão analisados os factores que maior influência exercem sobre os consumidores, no momento da compra. Considerando uma fase de pré-compra (momento que contempla consumidores que nunca utilizaram companhias aéreas low cost) e uma fase de pós-compra (momento que contempla consumidores que utilizam e consumidores que deixaram de utilizar este tipo de companhias), serão analisados os motivos que os levam a optar por um tipo em detrimento de outro.

Theoretical Rationalization of the Singlet–Triplet Gap in OLEDs Materials: Impact of Charge-Transfer Character

New materials for OLED applications with low singlet–triplet energy splitting have been recently synthesized in order to allow for the conversion of triplet into singlet excitons (emitting light) via a Thermally Activated Delayed Fluorescence (TADF) process, which involves excited-states with a non-negligible amount of Charge-Transfer (CT). The accurate modeling of these states with Time-Dependent Density Functional Theory (TD-DFT), the most used method so far because of the favorable trade-off between accuracy and computational cost, is however particularly challenging. We carefully address this issue here by considering materials with small (high) singlet–triplet gap acting as emitter (host) in OLEDs and by comparing the accuracy of TD-DFT and the corresponding Tamm-Dancoff Approximation (TDA), which is found to greatly reduce error bars with respect to experiments thanks to better estimates for the lowest singlet–triplet transition. Finally, we quantitatively correlate the singlet–triplet splitting values with the extent of CT, using for it a simple metric extracted from calculations with double-hybrid functionals, that might be applied in further molecular engineering studies.

Impact of genetic polymorphisms determining leukocyte/neutrophil count on chemotherapy toxicity

Nous avons investigué la relation entre les polymorphismes de nucléotides simples (SNPs) chez trois gènes/loci candidats : DARC, CXCL2 et le loci ORMDL3-GSDMA-CSF3 situés sur le chromosome 17q21 et les complications neutropéniques et infectieuses qui en résultent durant la chimiothérapie chez les patients atteints de la leucémie lymphoblastique aigue. Ces loci codent pour certaines composantes du système immunitaire altérant la concentration de chémokines et leur distribution (DARC), stimulant le relâchement et la migration des neutophiles de la moelle épinière (CXCL2) et régulant la prolifération et la survie des granulocytes (G-CSF). Il est possible que des polymorphismes dans ces loci lorsqu’associés à de la chimiothérapie puissent mettre des individus suceptibles à un risque plus élevé de complication reliées à la chimiothérapie. Une sélection des marqueurs SNPs dans ces gènes ont été génotypés chez des enfants traités au CHU Ste-Justine pour une ALL entre 1989 et 2005. Après correction pour tests multiples, un polymorphisme DARC rs3027012 situé dans le 5’UTR a été associé à un compte phagocytaire peu élevé (APC<500 et <1000 cellules/µL, p=0.001 and p=0.0005, respectivement) ainsi qu’une hospitalisation due à une neutropénie (p=0.007) ou due à une infection et/ou neutropénie (p=0.007). Un effet protecteur a été identifié pour la mutation non sense Gly42Asp variant rs12075 (p=0.006). Des polymorphismes sur le chromosome 17q2 étaient associés à une hospitalisation due à une infection (rs3859192, p= 0.004) et à une neutropénie (rs17609240, p=0.006) L’infection était aussi modulée par CXCL2 (rs16850408, p=0.008) Cette étude identifie pour la première fois que les loci modulant le décompte des leucocytes et des neutrophiles pourraient jouer un rôle dans de déclenchement de complications dues à la chimiothérapie et pourraient ainsi servir de marqueurs pour un ajustement et un suivi du traitement.

IMPACT OF PLUG-IN ELECTRIC VEHICLES AND WIND GENERATORS ON HARMONIC DISTORTION OF ELECTRIC DISTRIBUTION SYSTEMS

Harmonic distortion on voltages and currents increases with the increased penetration of Plug-in Electric Vehicle (PEV) loads in distribution systems. Wind Generators (WGs), which are source of harmonic currents, have some common harmonic profiles with PEVs. Thus, WGs can be utilized in careful ways to subside the effect of PEVs on harmonic distortion. This work studies the impact of PEVs on harmonic distortions and integration of WGs to reduce it. A decoupled harmonic three-phase unbalanced distribution system model is developed in OpenDSS, where PEVs and WGs are represented by harmonic current loads and sources respectively. The developed model is first used to solve harmonic power flow on IEEE 34-bus distribution system with low, moderate, and high penetration of PEVs, and its impact on current/voltage Total Harmonic Distortions (THDs) is studied. This study shows that the voltage and current THDs could be increased upto 9.5% and 50% respectively, in case of distribution systems with high PEV penetration and these THD values are significantly larger than the limits prescribed by the IEEE standards. Next, carefully sized WGs are selected at different locations in the 34-bus distribution system to demonstrate reduction in the current/voltage THDs. In this work, a framework is also developed to find optimal size of WGs to reduce THDs below prescribed operational limits in distribution circuits with PEV loads. The optimization framework is implemented in MATLAB using Genetic Algorithm, which is interfaced with the harmonic power flow model developed in OpenDSS. The developed framework is used to find optimal size of WGs on the 34-bus distribution system with low, moderate, and high penetration of PEVs, with an objective to reduce voltage/current THD deviations throughout the distribution circuits. With the optimal size of WGs in distribution systems with PEV loads, the current and voltage THDs are reduced below 5% and 7% respectively, which are within the limits prescribed by IEEE.

ELECTRON TRANSPORT IN LOW-DIMENSIONAL NANOSTRUCTURES - THEORETICAL STUDY WITH APPLICATION

Graphene as a carbon monolayer has attracted extensive research interest in recent years. My research work within the frame of density functional theory has suggested that positioning graphene in proximity to h-BN may induce a finite energy gap in graphene, which is important for device applications. For an AB-stacked graphene/BN bilayer, a finite gap is induced at the equilibrium configuration. This induced gap shows a linear relationship with the applied strain. For a graphene/BN/graphene trilayer, a negligible gap is predicted in the ground state due to the overall symmetry of the system. When an electric field is applied, a tunable gap can be obtained for both AAA and ABA stackings. Enhanced tunneling current in the AA-stacked bilayer nanoribbons is predicted compared to either single-layer or AB-stacked bilayer nanoribbons. Interlayer separation between the nanoribbons is shown to have a profound impact on the conducting features. The effect of boron or nitrogen doping on the electronic transport properties of C60 fullerene is studied. The BC59 fullerene exhibits a considerably higher current than the pristine or nitrogen doped fullerenes beyond the applied bias of 1 V, suggesting it can be an effective semiconductor in p-type devices. The interaction between nucleic acid bases - adenine (A), guanine (G), cytosine (C), thymine (T) and uracil (U) - and a hydrogen-passivated silicon nanowire (SiNW) is investigated. The binding energy of the bases with the SiNW shows the order: G > A~C~T~U. This suggests that the interaction strength of a hydrogen passivated SiNW with the nucleic acid bases is nearly the same-G being an exception. The nature of the interaction is suggested to be electrostatic.

Impact of genetic polymorphisms determining leukocyte/neutrophil count on chemotherapy toxicity

Nous avons investigué la relation entre les polymorphismes de nucléotides simples (SNPs) chez trois gènes/loci candidats : DARC, CXCL2 et le loci ORMDL3-GSDMA-CSF3 situés sur le chromosome 17q21 et les complications neutropéniques et infectieuses qui en résultent durant la chimiothérapie chez les patients atteints de la leucémie lymphoblastique aigue. Ces loci codent pour certaines composantes du système immunitaire altérant la concentration de chémokines et leur distribution (DARC), stimulant le relâchement et la migration des neutophiles de la moelle épinière (CXCL2) et régulant la prolifération et la survie des granulocytes (G-CSF). Il est possible que des polymorphismes dans ces loci lorsqu’associés à de la chimiothérapie puissent mettre des individus suceptibles à un risque plus élevé de complication reliées à la chimiothérapie. Une sélection des marqueurs SNPs dans ces gènes ont été génotypés chez des enfants traités au CHU Ste-Justine pour une ALL entre 1989 et 2005. Après correction pour tests multiples, un polymorphisme DARC rs3027012 situé dans le 5’UTR a été associé à un compte phagocytaire peu élevé (APC<500 et <1000 cellules/µL, p=0.001 and p=0.0005, respectivement) ainsi qu’une hospitalisation due à une neutropénie (p=0.007) ou due à une infection et/ou neutropénie (p=0.007). Un effet protecteur a été identifié pour la mutation non sense Gly42Asp variant rs12075 (p=0.006). Des polymorphismes sur le chromosome 17q2 étaient associés à une hospitalisation due à une infection (rs3859192, p= 0.004) et à une neutropénie (rs17609240, p=0.006) L’infection était aussi modulée par CXCL2 (rs16850408, p=0.008) Cette étude identifie pour la première fois que les loci modulant le décompte des leucocytes et des neutrophiles pourraient jouer un rôle dans de déclenchement de complications dues à la chimiothérapie et pourraient ainsi servir de marqueurs pour un ajustement et un suivi du traitement.

The impact of the gut microbiota on drug metabolism and clinical outcome

The significance of the gut microbiota as a determinant of drug pharmacokinetics and accordingly therapeutic response is of increasing importance with the advent of modern medicines characterised by low solubility and/or permeability, or modified-release. These physicochemical properties and release kinetics prolong drug residence times within the gastrointestinal tract, wherein biotransformation by commensal microbes can occur. As the evidence base in support of this supplementary metabolic “organ” expands, novel opportunities to engineer the microbiota for clinical benefit have emerged. This review provides an overview of microbe-mediated alteration of drug pharmacokinetics, with particular emphasis on studies demonstrating proof of concept in vivo. Additionally, recent advances in modulating the microbiota to improve clinical response to therapeutics are explored.

Assessing the impact of agricultural drought on maize prices in Kenya with the approach of the SPOT-VEGETATION NDVI remote sensing

The high cost of maize in Kenya is basically driven by East African regional commodity demand forces and agricultural drought. The production of maize, which is a common staple food in Kenya, is greatly affected by agricultural drought. However, calculations of drought risk and impact on maize production in Kenya is limited by the scarcity of reliable rainfall data. The objective of this study was to apply a novel hyperspectral remote sensing method to modelling temporal fluctuations of maize production and prices in five markets in Kenya. SPOT-VEGETATION NDVI time series were corrected for seasonal effects by computing the standardized NDVI anomalies. The maize residual price time series was further related to the NDVI seasonal anomalies using a multiple linear regression modelling approach. The result shows a moderately strong positive relationship (0.67) between residual price series and global maize prices. Maize prices were high during drought periods (i.e. negative NDVI anomalies) and low during wet seasons (i.e. positive NDVI anomalies). This study concludes that NDVI is a good index for monitoring the evolution of maize prices and food security emergency planning in Kenya. To obtain a very strong correlation for the relationship between the wholesale maize price and the global maize price, future research could consider adding other price-driving factors into the regression models.

Apprendre avec la technologie : l'impact sur l'enseignement et l'apprentissage de l’utilisation de la technologie numérique (SMARTBOARD) dans les classes

This research was devoted to gaining information on teachers? use of technology, specifically SMARTBOARD technology, for teaching and promoting learning in the classroom. Research has suggested that use of technology can enhance learning and classroom practices. This has resulted in administrators encouraging the use of SMARTBOARDS, installing them in classrooms and providing training and support for teachers to use this technology. Adoption of new technology, however, is not simple. It is even more challenging because making the best use of new technologies requires more than training; it requires a paradigm shift in teachers? pedagogical approach. Thus, while it may be reasonable to believe that all we need to do is show teachers the benefits of using the SMARTBOARD; research tells us that changing paradigms is difficult for a variety of reasons. This research had two main objectives. First, to discover what factors might positively or negatively affect teachers? decisions to take up this technology. Second, to investigate how the SMARTBOARD is used by teachers who have embraced it and how this impacts participation in classrooms. The project was divided into two parts; the first was a survey research (Part 1), and the second was an ethnographic study (Part 2). A thirty-nine item questionnaire was designed to obtain information on teachers? use of technology and the SMARTBOARD. The questionnaire was distributed to fifty teachers at two EMSB schools: James Lyng Adult Centre (JLAC) and the High School of Montreal (HSM). Part 2 was an ethnographic qualitative study of two classes (Class A, Class B) at JLAC. Class A was taught by a male teacher, an early-adopter of technology and a high-level user of the SMARTBOARD; Class B was taught by a female teacher who was more traditional and a low-level user. These teachers were selected because they had similar years of experience and general competence in their subject matter but differed in their use of the technology. The enrollment in Class A and Class B were twenty-three and twenty-four adult students, respectively. Each class was observed for 90 minutes on three consecutive days in April 2010. Data collection consisted of videotapes of the entire period, and observational field notes with a graphical recording of participatory actions. Information from the graphical recording was converted to sociograms, a graphic representation of social links among individuals involved in joint action. The sociogram data was tabulated as quantified data. The survey results suggest that although most teachers are interested in and use some form of technology in their teaching, there is a tendency for factors of gender and years of experience to influence the use of and opinions on using technology. A Chi Square analysis of the data revealed (a) a significant difference (2 = 6.031, p < .049) for gender in that male teachers are more likely to be interested in the latest pedagogic innovation compared to female teachers; and, (b) a significant difference for years of experience (2 = 10.945, p < .004), showing that teachers with ?6 years experience were more likely to use the SMARTBOARD, compared to those with more experience (>6 years). All other items from the survey data produced no statistical difference. General trends show that (a) male teachers are more willing to say yes to using the SMARTBOARD compared to female teachers, and (b) teachers with less teaching experience were more likely to have positive opinions about using the SMARTBOARD compared to teachers with more experience. The ethnographic study results showed differences in students? response patterns in the two classrooms. Even though both teachers are experienced and competent, Teacher A elicited more participation from his students than Teacher B. This was so partly because he used the SMARTBOARD to present visual materials that the students could easily respond to. By comparison, Teacher B used traditional media or methods to present most of her course material. While these methods also used visual materials, students were not able to easily relate to these smaller, static images and did not readily engage with the material. This research demonstrates a generally positive attitude by teachers towards use of the SMARTBOARD and a generally positive role of this technology in enhancing students? learning and engagement in the classroom. However, there are many issues related to the SMARTBOARD use that still need to be examined. A particular point is whether teachers feel adequately trained to integrate SMARTBOARD technology into their curricula. And, whether the gender difference revealed is related to other factors like a need for more support, other responsibilities, or a general sense of anxiety when it comes to technology. Greater opportunity for training and ongoing support may be one way to increase teacher use of the SMARTBOARD; particularly for teachers with more experience (>6 years) and possibly also for female teachers.

Integrated soil fertility management in eastern and western Africa: The role of knowledge and innovation systems, its adoption and impact

The rise in population growth, as well as nutrient mining, has contributed to low agricultural productivity in Sub-Saharan Africa (SSA). A plethora of technologies to boost agricultural production have been developed but the dissemination of these agricultural innovations and subsequent uptake by smallholder farmers has remained a challenge. Scientists and philanthropists have adopted the Integrated Soil Fertility Management (ISFM) paradigm as a means to promote sustainable intensification of African farming systems. This comparative study aimed: 1) To assess the efficacy of Agricultural Knowledge and Innovation Systems (AKIS) in East (Kenya) and West (Ghana) Africa in the communication and dissemination of ISFM (Study I); 2) To investigate how specifically soil quality, and more broadly socio-economic status and institutional factors, influence farmer adoption of ISFM (Study II); and 3) To assess the effect of ISFM on maize yield and total household income of smallholder farmers (Study III). To address these aims, a mixed methodology approach was employed for study I. AKIS actors were subjected to social network analysis methods and in-depth interviews. Structured questionnaires were administered to 285 farming households in Tamale and 300 households in Kakamega selected using a stratified random sampling approach. There was a positive relationship between complete ISFM awareness among farmers and weak knowledge ties to both formal and informal actors at both research locations. The Kakamega AKIS revealed a relationship between complete ISFM awareness among farmers and them having strong knowledge ties to formal actors implying that further integration of formal actors with farmers’ local knowledge is crucial for the agricultural development progress. The structured questionnaire was also utilized to answer the query pertaining to study II. Soil samples (0-20 cm depth) were drawn from 322 (Tamale, Ghana) and 459 (Kakamega, Kenya) maize plots and analysed non-destructively for various soil fertility indicators. Ordinal regression modeling was applied to assess the cumulative adoption of ISFM. According to model estimates, soil carbon seemed to preclude farmers from intensifying input use in Tamale, whereas in Kakamega it spurred complete adoption. This varied response by farmers to soil quality conditions is multifaceted. From the Tamale perspective, it is consistent with farmers’ tendency to judiciously allocate scarce resources. Viewed from the Kakamega perspective, it points to a need for farmers here to intensify agricultural production in order to foster food security. In Kakamega, farmers with more acidic soils were more likely to adopt ISFM. Other household and farm-level factors necessary for ISFM adoption included off-farm income, livestock ownership, farmer associations, and market inter-linkages. Finally, in study III a counterfactual model was used to calculate the difference in outcomes (yield and household income) of the treatment (ISFM adoption) in order to estimate causal effects of ISFM adoption. Adoption of ISFM contributed to a yield increase of 16% in both Tamale and Kakamega. The innovation affected total household income only in Tamale, where ISFM adopters had an income gain of 20%. This may be attributable to the different policy contexts under which the two sets of farmers operate. The main recommendations underscored the need to: (1) improve the functioning of AKIS, (2) enhance farmer access to hybrid maize seed and credit, (3) and conduct additional multi-locational studies as farmers operate under varying contexts.

Impact of salt reduction on biogenic amines, fatty acids, microbiota, texture and sensory profile in traditional blood dry-cured sausages

Meat industry needs to reduce salt in their products due to health issues. The present study evaluated the effect of salt reduction from 6% to 3% in two Portuguese traditional blood dry-cured sausages. Physicochemical and microbiological parameters, biogenic amines, fatty acids and texture profiles and sensory panel evaluations were considered. Differences due to salt reduction were perceptible in a faint decline of water activity, which slightly favoured microbial growth. Total biogenic amines content ranged from 88.86 to 796.68 mg kg 1 fresh matter, with higher amounts, particularly of cadaverine, histamine and tyramine, in low-salt products. Still, histamine and other vasoactive amines remained at low levels, thus not affecting consumers’ health. Regarding fatty acids, no significant differences were observed due to salt. However, texture profile analysis revealed lower resilience and cohesiveness in low-salt products, although no textural changes were observed by the sensory panel. Nevertheless, low-salt sausages were clearly preferred by panellists.