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Objective Functional magnetic resonance imaging (fMRI) is a non-invasive neuroimaging technique widely used in olfactory research. During a typical fMRI olfactory block-design, one functional "run" refers to a combination of multiple blocks with continuous brain image acquisition. The current study investigated the length of functional runs on odor-induced brain response signals (blood oxygen level dependent [BLOD]) within the primary and key secondary olfactory areas. Methods Twenty-five female adults (age range 19 to 30 years, mean age 25 years) underwent a block-design fMRI measurement with odor stimulation. Twelve participants received the odor stimuli within a short run paradigm (six blocks in each 4-minute run, eight runs in total), and 13 participants received the odor stimulation with a long-run paradigm (12 blocks in each 8-minute run, four runs in total). For each paradigm, two odors (peach and rose) were alternatingly presented between runs. Participants rated odor intensity and pleasantness at the end of each run. Ratings and fMRI data were analyzed for different subsections and compared between groups. Results There was a higher level of brain activation in the insula and orbitofrontal cortex during the short-run paradigm as compared to the long-run paradigm. However, there was no difference for odor intensity or pleasantness ratings. Conclusion The current study suggested the employment of short runs with multiple repetitions for odor stimulation during fMRI research. Level of Evidence 3 Laryngoscope, 2019

Background and Objective: Fatigue is common among stroke survivors; and has significant negative consequences. However, long-term follow-up on post-stroke fatigue and it's association with cognitive and physiological parameters remains vague. Methods: A prospective cohort study was carried out on 38 young stroke survivors (aged 18–65 at stroke onset) living in the community 10 years after first-ever stroke. Fatigue was assessed by Fatigue assessment scale (FAS). Global cognition and cognitive sub-domains were assessed repeatedly at 1 week, 7 months, and 10 years after their first-ever stroke. Univariate correlation analysis was used to investigate associations and multivariate regression was used to investigate predictors and association with fatigue. Results: At 10-years follow-up after stroke onset, more than half of the 38 participants suffered from fatigue [with median score 25 on FAS with 25–75% percentile (21–28)]. Most of them were independent in their everyday life [mRS median score 1 (0–2)]. In univariate correlation analyses, higher fatigue score was significantly correlated to higher independence in the daily activity, higher BMI, anxiety, higher scores on global cognition and better working memory at 10-years follow-up as well as better visuospatial functions after 7 months and 10-years. In a multiple regression analysis, only visuospatial function at 7-months follow-up was a significant predictor of fatigue 10 years after stroke onset [F = 23.07, p < 0.009], with adjusted (R2 = 0.815) i.e., higher scores on Block design were associated with more fatigue. Conclusion: Our results extended the time course of post-stroke fatigue up to 10 years after stroke onset. The participants with more fatigue performed better in cognitive assessments and daily activity, which indicated dissociation between fatigue and fatigability among stroke patients. Visuospatial function at the sub-acute phase predicted independently late post-stroke fatigue. This may offer a br

Background and Objective: Fatigue is common among stroke survivors; and has significant negative consequences. However, long-term follow-up on post-stroke fatigue and it's association with cognitive and physiological parameters remains vague. Methods: A prospective cohort study was carried out on 38 young stroke survivors (aged 18–65 at stroke onset) living in the community 10 years after first-ever stroke. Fatigue was assessed by Fatigue assessment scale (FAS). Global cognition and cognitive sub-domains were assessed repeatedly at 1 week, 7 months, and 10 years after their first-ever stroke. Univariate correlation analysis was used to investigate associations and multivariate regression was used to investigate predictors and association with fatigue. Results: At 10-years follow-up after stroke onset, more than half of the 38 participants suffered from fatigue [with median score 25 on FAS with 25–75% percentile (21–28)]. Most of them were independent in their everyday life [mRS median score 1 (0–2)]. In univariate correlation analyses, higher fatigue score was significantly correlated to higher independence in the daily activity, higher BMI, anxiety, higher scores on global cognition and better working memory at 10-years follow-up as well as better visuospatial functions after 7 months and 10-years. In a multiple regression analysis, only visuospatial function at 7-months follow-up was a significant predictor of fatigue 10 years after stroke onset [F = 23.07, p < 0.009], with adjusted (R2 = 0.815) i.e., higher scores on Block design were associated with more fatigue. Conclusion: Our results extended the time course of post-stroke fatigue up to 10 years after stroke onset. The participants with more fatigue performed better in cognitive assessments and daily activity, which indicated dissociation between fatigue and fatigability among stroke patients. Visuospatial function at the sub-acute phase predicted independently late post-stroke fatigue. This may offer a br

Background and Objective: Fatigue is common among stroke survivors; and has significant negative consequences. However, long-term follow-up on post-stroke fatigue and it's association with cognitive and physiological parameters remains vague. Methods: A prospective cohort study was carried out on 38 young stroke survivors (aged 18–65 at stroke onset) living in the community 10 years after first-ever stroke. Fatigue was assessed by Fatigue assessment scale (FAS). Global cognition and cognitive sub-domains were assessed repeatedly at 1 week, 7 months, and 10 years after their first-ever stroke. Univariate correlation analysis was used to investigate associations and multivariate regression was used to investigate predictors and association with fatigue. Results: At 10-years follow-up after stroke onset, more than half of the 38 participants suffered from fatigue [with median score 25 on FAS with 25–75% percentile (21–28)]. Most of them were independent in their everyday life [mRS median score 1 (0–2)]. In univariate correlation analyses, higher fatigue score was significantly correlated to higher independence in the daily activity, higher BMI, anxiety, higher scores on global cognition and better working memory at 10-years follow-up as well as better visuospatial functions after 7 months and 10-years. In a multiple regression analysis, only visuospatial function at 7-months follow-up was a significant predictor of fatigue 10 years after stroke onset [F = 23.07, p < 0.009], with adjusted (R2 = 0.815) i.e., higher scores on Block design were associated with more fatigue. Conclusion: Our results extended the time course of post-stroke fatigue up to 10 years after stroke onset. The participants with more fatigue performed better in cognitive assessments and daily activity, which indicated dissociation between fatigue and fatigability among stroke patients. Visuospatial function at the sub-acute phase predicted independently late post-stroke fatigue. This may offer a br

Green walls that effectively treat greywater have the potential to become a part of the solution for the issues of water scarcity and pollution control in our cities. To develop reliable and efficient designs of such systems, the following two research questions were addressed: what would be the optimal design of a green wall for greywater treatment, and how tall should the system be to assure adequate treatment. This paper reports on (i) a long-term pollutant removal comparison study of two typical green wall configurations: pot and block designs, and (ii) a short-term profile study exploring pollutant retention at different heights of a three-level green wall, across different plant species. Removal of suspended solids (TSS), nitrogen (TN), phosphorus (TP), chemical oxygen demand (COD) and Escherichia coli was tested, as well as various physical parameters. Pot and block designs were found to exhibit similar pollutant removal performance for standard and high inflow concentrations, while the block design was more resistant to drying. However, due to its multiple practical advantages, pot designs are favoured. The greatest removal was achieved within the top green wall level for all studied pollutants, while subsequent levels facilitated further removal of TSS, COD, and TN. Interestingly, colour, pH, and EC increased after each green wall level, which must be taken into account to determine the maximum height of these systems. The optimal size of the system was found to be dependent on plant species choice. The results were used to create practical recommendations for the effective design of greywater treatment green walls.

Biosolids generated as waste from a Wastewater Treatment Plant (WTP) are a pollution problem by the provision of large volumes in landfills and the waste of their potential as an agricultural input. The research conducted trials to analyze the agricultural use of biosolids in a food company's WTP, their effects on the germination and development of the vegetal plant species Coriandrum sativum were assessed through trials that mixed different amounts of biosolids, land soil and commercial fertilizer, and took into account: planting site characteristics, biosolid and Coriandrum sativum. A random block design was made to compare treatments understudy and resulted in the combination of 50% biosolids with 50% land soil was the best test by germination, height, mass and length of the roots of the plant studied. In the evaluation of results, the behavior of dependent variables was analyzed: germination, height, mass and length with respect to the four test types with their respective repetitions using ANOVA and Fisher's significant minimum difference (LSD) to determine the effect the biosolid had on the plant and to know the optimal dose for its development. The germination rate (GR) was also determined in the trials, and 98.3% was found for the best treatment indicating that the substrate does not contain phytotoxic elements.

Biosolids generated as waste from a Wastewater Treatment Plant (WTP) are a pollution problem by the provision of large volumes in landfills and the waste of their potential as an agricultural input. The research conducted trials to analyze the agricultural use of biosolids in a food company's WTP, their effects on the germination and development of the vegetal plant species Coriandrum sativum were assessed through trials that mixed different amounts of biosolids, land soil and commercial fertilizer, and took into account: planting site characteristics, biosolid and Coriandrum sativum. A random block design was made to compare treatments understudy and resulted in the combination of 50% biosolids with 50% land soil was the best test by germination, height, mass and length of the roots of the plant studied. In the evaluation of results, the behavior of dependent variables was analyzed: germination, height, mass and length with respect to the four test types with their respective repetitions using ANOVA and Fisher's significant minimum difference (LSD) to determine the effect the biosolid had on the plant and to know the optimal dose for its development. The germination rate (GR) was also determined in the trials, and 98.3% was found for the best treatment indicating that the substrate does not contain phytotoxic elements.

Background and Objective: Fatigue is common among stroke survivors; and has significant negative consequences. However, long-term follow-up on post-stroke fatigue and it's association with cognitive and physiological parameters remains vague. Methods: A prospective cohort study was carried out on 38 young stroke survivors (aged 18–65 at stroke onset) living in the community 10 years after first-ever stroke. Fatigue was assessed by Fatigue assessment scale (FAS). Global cognition and cognitive sub-domains were assessed repeatedly at 1 week, 7 months, and 10 years after their first-ever stroke. Univariate correlation analysis was used to investigate associations and multivariate regression was used to investigate predictors and association with fatigue. Results: At 10-years follow-up after stroke onset, more than half of the 38 participants suffered from fatigue [with median score 25 on FAS with 25–75% percentile (21–28)]. Most of them were independent in their everyday life [mRS median score 1 (0–2)]. In univariate correlation analyses, higher fatigue score was significantly correlated to higher independence in the daily activity, higher BMI, anxiety, higher scores on global cognition and better working memory at 10-years follow-up as well as better visuospatial functions after 7 months and 10-years. In a multiple regression analysis, only visuospatial function at 7-months follow-up was a significant predictor of fatigue 10 years after stroke onset [F = 23.07, p < 0.009], with adjusted (R2 = 0.815) i.e., higher scores on Block design were associated with more fatigue. Conclusion: Our results extended the time course of post-stroke fatigue up to 10 years after stroke onset. The participants with more fatigue performed better in cognitive assessments and daily activity, which indicated dissociation between fatigue and fatigability among stroke patients. Visuospatial function at the sub-acute phase predicted independently late post-stroke fatigue. This may offer a br

Background and Objective: Fatigue is common among stroke survivors; and has significant negative consequences. However, long-term follow-up on post-stroke fatigue and it's association with cognitive and physiological parameters remains vague. Methods: A prospective cohort study was carried out on 38 young stroke survivors (aged 18–65 at stroke onset) living in the community 10 years after first-ever stroke. Fatigue was assessed by Fatigue assessment scale (FAS). Global cognition and cognitive sub-domains were assessed repeatedly at 1 week, 7 months, and 10 years after their first-ever stroke. Univariate correlation analysis was used to investigate associations and multivariate regression was used to investigate predictors and association with fatigue. Results: At 10-years follow-up after stroke onset, more than half of the 38 participants suffered from fatigue [with median score 25 on FAS with 25–75% percentile (21–28)]. Most of them were independent in their everyday life [mRS median score 1 (0–2)]. In univariate correlation analyses, higher fatigue score was significantly correlated to higher independence in the daily activity, higher BMI, anxiety, higher scores on global cognition and better working memory at 10-years follow-up as well as better visuospatial functions after 7 months and 10-years. In a multiple regression analysis, only visuospatial function at 7-months follow-up was a significant predictor of fatigue 10 years after stroke onset [F = 23.07, p < 0.009], with adjusted (R2 = 0.815) i.e., higher scores on Block design were associated with more fatigue. Conclusion: Our results extended the time course of post-stroke fatigue up to 10 years after stroke onset. The participants with more fatigue performed better in cognitive assessments and daily activity, which indicated dissociation between fatigue and fatigability among stroke patients. Visuospatial function at the sub-acute phase predicted independently late post-stroke fatigue. This may offer a br

We introduce the notion of quasi-orthogonal cocycle. This is motivated in part by the maximal determinant problem for square {±1}-matrices of size congruent to 2 modulo 4. Quasi-orthogonal cocycles are analogous to the orthogonal cocycles of algebraic design theory. Equivalences with new and known combinatorial objects afforded by this analogy, such as quasi-Hadamard groups, relative quasi-difference sets, and certain partially balanced incomplete block designs, are proved.

We introduce the notion of quasi-orthogonal cocycle. This is motivated in part by the maximal determinant problem for square {±1}-matrices of size congruent to 2 modulo 4. Quasi-orthogonal cocycles are analogous to the orthogonal cocycles of algebraic design theory. Equivalences with new and known combinatorial objects afforded by this analogy, such as quasi-Hadamard groups, relative quasi-difference sets, and certain partially balanced incomplete block designs, are proved.

We introduce the notion of quasi-orthogonal cocycle. This is motivated in part by the maximal determinant problem for square {±1}-matrices of size congruent to 2 modulo 4. Quasi-orthogonal cocycles are analogous to the orthogonal cocycles of algebraic design theory. Equivalences with new and known combinatorial objects afforded by this analogy, such as quasi-Hadamard groups, relative quasi-difference sets, and certain partially balanced incomplete block designs, are proved.

We introduce the notion of quasi-orthogonal cocycle. This is motivated in part by the maximal determinant problem for square {±1}-matrices of size congruent to 2 modulo 4. Quasi-orthogonal cocycles are analogous to the orthogonal cocycles of algebraic design theory. Equivalences with new and known combinatorial objects afforded by this analogy, such as quasi-Hadamard groups, relative quasi-difference sets, and certain partially balanced incomplete block designs, are proved.

We introduce the notion of quasi-orthogonal cocycle. This is motivated in part by the maximal determinant problem for square {±1}-matrices of size congruent to 2 modulo 4. Quasi-orthogonal cocycles are analogous to the orthogonal cocycles of algebraic design theory. Equivalences with new and known combinatorial objects afforded by this analogy, such as quasi-Hadamard groups, relative quasi-difference sets, and certain partially balanced incomplete block designs, are proved.

We introduce the notion of quasi-orthogonal cocycle. This is motivated in part by the maximal determinant problem for square {±1}-matrices of size congruent to 2 modulo 4. Quasi-orthogonal cocycles are analogous to the orthogonal cocycles of algebraic design theory. Equivalences with new and known combinatorial objects afforded by this analogy, such as quasi-Hadamard groups, relative quasi-difference sets, and certain partially balanced incomplete block designs, are proved.

Epub ahead of print 27/07/2016, Multi-echo fMRI, particularly the multi-echo independent component analysis (ME-ICA) algorithm, has previously proven useful for increasing the sensitivity and reducing false positives for functional MRI (fMRI) based resting state connectivity studies. Less is known about its efficacy for task-based fMRI, especially at the single subject level. This work, which focuses exclusively on individual subject results, compares ME-ICA to single-echo fMRI and a voxel-wise T2⁎ weighted combination of multi-echo data for task-based fMRI under the following scenarios: cardiac-gated block designs, constant repetition time (TR) block designs, and constant TR rapid event-related designs. Performance is evaluated primarily in terms of sensitivity (i.e., activation extent, activation magnitude, percent detected trials and effect size estimates) using five different tasks expected to evoke neuronal activity in a distributed set of regions. The ME-ICA algorithm significantly outperformed all other evaluated processing alternatives in all scenarios. Largest improvements were observed for the cardiac-gated dataset, where ME-ICA was able to reliably detect and remove non-neural T1 signal fluctuations caused by non-constant repetition times. Although ME-ICA also outperformed the other options in terms of percent detection of individual trials for rapid event-related experiments, only 46% of all events were detected after ME-ICA; suggesting additional improvements in sensitivity are required to reliably detect individual short event occurrences. We conclude the manuscript with a detailed evaluation of ME-ICA outcomes and a discussion of how the ME-ICA algorithm could be further improved. Overall, our results suggest that ME-ICA constitutes a versatile, powerful approach for advanced denoising of task-based fMRI, not just resting-state data.

Epub ahead of print 27/07/2016, Multi-echo fMRI, particularly the multi-echo independent component analysis (ME-ICA) algorithm, has previously proven useful for increasing the sensitivity and reducing false positives for functional MRI (fMRI) based resting state connectivity studies. Less is known about its efficacy for task-based fMRI, especially at the single subject level. This work, which focuses exclusively on individual subject results, compares ME-ICA to single-echo fMRI and a voxel-wise T2⁎ weighted combination of multi-echo data for task-based fMRI under the following scenarios: cardiac-gated block designs, constant repetition time (TR) block designs, and constant TR rapid event-related designs. Performance is evaluated primarily in terms of sensitivity (i.e., activation extent, activation magnitude, percent detected trials and effect size estimates) using five different tasks expected to evoke neuronal activity in a distributed set of regions. The ME-ICA algorithm significantly outperformed all other evaluated processing alternatives in all scenarios. Largest improvements were observed for the cardiac-gated dataset, where ME-ICA was able to reliably detect and remove non-neural T1 signal fluctuations caused by non-constant repetition times. Although ME-ICA also outperformed the other options in terms of percent detection of individual trials for rapid event-related experiments, only 46% of all events were detected after ME-ICA; suggesting additional improvements in sensitivity are required to reliably detect individual short event occurrences. We conclude the manuscript with a detailed evaluation of ME-ICA outcomes and a discussion of how the ME-ICA algorithm could be further improved. Overall, our results suggest that ME-ICA constitutes a versatile, powerful approach for advanced denoising of task-based fMRI, not just resting-state data.

Epub ahead of print 27/07/2016, Multi-echo fMRI, particularly the multi-echo independent component analysis (ME-ICA) algorithm, has previously proven useful for increasing the sensitivity and reducing false positives for functional MRI (fMRI) based resting state connectivity studies. Less is known about its efficacy for task-based fMRI, especially at the single subject level. This work, which focuses exclusively on individual subject results, compares ME-ICA to single-echo fMRI and a voxel-wise T2⁎ weighted combination of multi-echo data for task-based fMRI under the following scenarios: cardiac-gated block designs, constant repetition time (TR) block designs, and constant TR rapid event-related designs. Performance is evaluated primarily in terms of sensitivity (i.e., activation extent, activation magnitude, percent detected trials and effect size estimates) using five different tasks expected to evoke neuronal activity in a distributed set of regions. The ME-ICA algorithm significantly outperformed all other evaluated processing alternatives in all scenarios. Largest improvements were observed for the cardiac-gated dataset, where ME-ICA was able to reliably detect and remove non-neural T1 signal fluctuations caused by non-constant repetition times. Although ME-ICA also outperformed the other options in terms of percent detection of individual trials for rapid event-related experiments, only 46% of all events were detected after ME-ICA; suggesting additional improvements in sensitivity are required to reliably detect individual short event occurrences. We conclude the manuscript with a detailed evaluation of ME-ICA outcomes and a discussion of how the ME-ICA algorithm could be further improved. Overall, our results suggest that ME-ICA constitutes a versatile, powerful approach for advanced denoising of task-based fMRI, not just resting-state data.

[ES] El desarrollo de las técnicas de neuroimagen ha sido uno de los factores que han contribuido a la mejora de los tratamientos neuroquirúrgicos, lo que se ha traducido en un incremento de la esperanza de vida y una disminución de la morbilidad y de otros problemas posteriores a las intervenciones. Entre estas técnicas destaca actualmente la aplicación de la resonancia magnética funcional (fMRI). La técnica funcional, consiste en monitorear la actividad cerebral de forma no invasiva, mediante resonancia magnética, generando mapas funcionales que permiten registrar las zonas del cerebro que se han activado tras realizar un proceso mental, motor, visual, auditivo, ó sensorial. El principio de la resonancia magnética funcional se basa en la detección de los cambios hemodinámicos producidos por el incremento en la actividad en una zona del cerebro, constituyendo de esta forma una medición indirecta de la actividad neuronal. En el presente trabajo abordaremos la problemática del diseño y validación de un paradigma para el estudio de fMRI para la compresión del lenguaje por medio visual. Este trabajo se dividirá en 3 grandes ítems: estado del arte, selección y validación del paradigma y discusión de resultados. En el estado del arte estudiaremos toda la teoría relacionada a MRI y fMRI, pasando por los principios básicos de la señal BOLD, técnicas de muestreo y adquisición de la fMRI en funciones cognitivas pasando por el estudio de protocolos utilizados en la compresión del lenguaje. En el proceso de selección del paradigma analizaremos aquel que se acerca más a nuestras expectativas de resultados esperados para luego validar en voluntarios sanos. Recogidas todas las muestras de nuestros sujetos a estudio se analizarán estadísticamente para culminar en un proceso de discusión de los resultados obtenidos. En la discusión de resultados abordaremos la problemática de la selección del paradigma, las adquisiciones obtenidas y los trabajos a futuro. Concluimos diciendo que to

[ES] El desarrollo de las técnicas de neuroimagen ha sido uno de los factores que han contribuido a la mejora de los tratamientos neuroquirúrgicos, lo que se ha traducido en un incremento de la esperanza de vida y una disminución de la morbilidad y de otros problemas posteriores a las intervenciones. Entre estas técnicas destaca actualmente la aplicación de la resonancia magnética funcional (fMRI). La técnica funcional, consiste en monitorear la actividad cerebral de forma no invasiva, mediante resonancia magnética, generando mapas funcionales que permiten registrar las zonas del cerebro que se han activado tras realizar un proceso mental, motor, visual, auditivo, ó sensorial. El principio de la resonancia magnética funcional se basa en la detección de los cambios hemodinámicos producidos por el incremento en la actividad en una zona del cerebro, constituyendo de esta forma una medición indirecta de la actividad neuronal. En el presente trabajo abordaremos la problemática del diseño y validación de un paradigma para el estudio de fMRI para la compresión del lenguaje por medio visual. Este trabajo se dividirá en 3 grandes ítems: estado del arte, selección y validación del paradigma y discusión de resultados. En el estado del arte estudiaremos toda la teoría relacionada a MRI y fMRI, pasando por los principios básicos de la señal BOLD, técnicas de muestreo y adquisición de la fMRI en funciones cognitivas pasando por el estudio de protocolos utilizados en la compresión del lenguaje. En el proceso de selección del paradigma analizaremos aquel que se acerca más a nuestras expectativas de resultados esperados para luego validar en voluntarios sanos. Recogidas todas las muestras de nuestros sujetos a estudio se analizarán estadísticamente para culminar en un proceso de discusión de los resultados obtenidos. En la discusión de resultados abordaremos la problemática de la selección del paradigma, las adquisiciones obtenidas y los trabajos a futuro. Concluimos diciendo que to

[ES] El desarrollo de las técnicas de neuroimagen ha sido uno de los factores que han contribuido a la mejora de los tratamientos neuroquirúrgicos, lo que se ha traducido en un incremento de la esperanza de vida y una disminución de la morbilidad y de otros problemas posteriores a las intervenciones. Entre estas técnicas destaca actualmente la aplicación de la resonancia magnética funcional (fMRI). La técnica funcional, consiste en monitorear la actividad cerebral de forma no invasiva, mediante resonancia magnética, generando mapas funcionales que permiten registrar las zonas del cerebro que se han activado tras realizar un proceso mental, motor, visual, auditivo, ó sensorial. El principio de la resonancia magnética funcional se basa en la detección de los cambios hemodinámicos producidos por el incremento en la actividad en una zona del cerebro, constituyendo de esta forma una medición indirecta de la actividad neuronal. En el presente trabajo abordaremos la problemática del diseño y validación de un paradigma para el estudio de fMRI para la compresión del lenguaje por medio visual. Este trabajo se dividirá en 3 grandes ítems: estado del arte, selección y validación del paradigma y discusión de resultados. En el estado del arte estudiaremos toda la teoría relacionada a MRI y fMRI, pasando por los principios básicos de la señal BOLD, técnicas de muestreo y adquisición de la fMRI en funciones cognitivas pasando por el estudio de protocolos utilizados en la compresión del lenguaje. En el proceso de selección del paradigma analizaremos aquel que se acerca más a nuestras expectativas de resultados esperados para luego validar en voluntarios sanos. Recogidas todas las muestras de nuestros sujetos a estudio se analizarán estadísticamente para culminar en un proceso de discusión de los resultados obtenidos. En la discusión de resultados abordaremos la problemática de la selección del paradigma, las adquisiciones obtenidas y los trabajos a futuro. Concluimos diciendo que to

Rs9722 and rs1051169 have been reported as affecting the levels of S100B in the serum or the brain, and haplotypes containing these two SNPs have been associated with schizophrenia. The current study investigated the role of the S100B gene in an endophenotype of schizophrenia-spatial disability. 304 schizophrenia patients and 196 healthy controls were given a block design task and a mental rotation task. Results showed that the two aforementioned SNPs and related haplotypes were associated with the spatial disability of schizophrenia patients. Specifically, risk factors for the elevated S100B levels, including the A allele of rs9722, the G allele of rs1051169, and the AG haplotype, were associated with a poorer performance on both tests of spatial ability, especially the mental rotation task. These results implicate a role for S100B gene polymorphisms in the cognitive functions of schizophrenia patients and encourage further investigation into spatial disability as an endophenotype of schizophrenia.

Rs9722 and rs1051169 have been reported as affecting the levels of S100B in the serum or the brain, and haplotypes containing these two SNPs have been associated with schizophrenia. The current study investigated the role of the S100B gene in an endophenotype of schizophrenia-spatial disability. 304 schizophrenia patients and 196 healthy controls were given a block design task and a mental rotation task. Results showed that the two aforementioned SNPs and related haplotypes were associated with the spatial disability of schizophrenia patients. Specifically, risk factors for the elevated S100B levels, including the A allele of rs9722, the G allele of rs1051169, and the AG haplotype, were associated with a poorer performance on both tests of spatial ability, especially the mental rotation task. These results implicate a role for S100B gene polymorphisms in the cognitive functions of schizophrenia patients and encourage further investigation into spatial disability as an endophenotype of schizophrenia.

Latin squares have been historically used in order to create statistical designs in which, starting from a small number of experiments, it can be obtained a large experimental space. In this sense, the optimization of the selection of Latin squares can be decisive. A factor to take into account is the symmetry that the experimental space must verify and which is established by the autotopism group of each Latin square. Although the size of this group is known for Latin squares of order up to 10, a classification of the different symmetries has not yet been done. In this paper, given a cycle structure of a Latin square autotopism, it is studied the regularity of the incidence structure formed by the set of autotopisms having this cycle structure and the set of Latin squares remaining stable by at least one of the previous autotopisms. Moreover, it is proven that every substructure given by the isotopism class of a Latin square is a 1-(v,k,r) design. Since the corresponding parameter k is known for Latin squares of order up to 7, we obtain the rest of the parameters of all these substructures and, consequently, a classification of all possible symmetries is reached for these orders.

Latin squares have been historically used in order to create statistical designs in which, starting from a small number of experiments, it can be obtained a large experimental space. In this sense, the optimization of the selection of Latin squares can be decisive. A factor to take into account is the symmetry that the experimental space must verify and which is established by the autotopism group of each Latin square. Although the size of this group is known for Latin squares of order up to 10, a classification of the different symmetries has not yet been done. In this paper, given a cycle structure of a Latin square autotopism, it is studied the regularity of the incidence structure formed by the set of autotopisms having this cycle structure and the set of Latin squares remaining stable by at least one of the previous autotopisms. Moreover, it is proven that every substructure given by the isotopism class of a Latin square is a 1-(v,k,r) design. Since the corresponding parameter k is known for Latin squares of order up to 7, we obtain the rest of the parameters of all these substructures and, consequently, a classification of all possible symmetries is reached for these orders.

Latin squares have been historically used in order to create statistical designs in which, starting from a small number of experiments, it can be obtained a large experimental space. In this sense, the optimization of the selection of Latin squares can be decisive. A factor to take into account is the symmetry that the experimental space must verify and which is established by the autotopism group of each Latin square. Although the size of this group is known for Latin squares of order up to 10, a classification of the different symmetries has not yet been done. In this paper, given a cycle structure of a Latin square autotopism, it is studied the regularity of the incidence structure formed by the set of autotopisms having this cycle structure and the set of Latin squares remaining stable by at least one of the previous autotopisms. Moreover, it is proven that every substructure given by the isotopism class of a Latin square is a 1-(v,k,r) design. Since the corresponding parameter k is known for Latin squares of order up to 7, we obtain the rest of the parameters of all these substructures and, consequently, a classification of all possible symmetries is reached for these orders.

Latin squares have been historically used in order to create statistical designs in which, starting from a small number of experiments, it can be obtained a large experimental space. In this sense, the optimization of the selection of Latin squares can be decisive. A factor to take into account is the symmetry that the experimental space must verify and which is established by the autotopism group of each Latin square. Although the size of this group is known for Latin squares of order up to 10, a classification of the different symmetries has not yet been done. In this paper, given a cycle structure of a Latin square autotopism, it is studied the regularity of the incidence structure formed by the set of autotopisms having this cycle structure and the set of Latin squares remaining stable by at least one of the previous autotopisms. Moreover, it is proven that every substructure given by the isotopism class of a Latin square is a 1-(v,k,r) design. Since the corresponding parameter k is known for Latin squares of order up to 7, we obtain the rest of the parameters of all these substructures and, consequently, a classification of all possible symmetries is reached for these orders.

Latin squares have been historically used in order to create statistical designs in which, starting from a small number of experiments, it can be obtained a large experimental space. In this sense, the optimization of the selection of Latin squares can be decisive. A factor to take into account is the symmetry that the experimental space must verify and which is established by the autotopism group of each Latin square. Although the size of this group is known for Latin squares of order up to 10, a classification of the different symmetries has not yet been done. In this paper, given a cycle structure of a Latin square autotopism, it is studied the regularity of the incidence structure formed by the set of autotopisms having this cycle structure and the set of Latin squares remaining stable by at least one of the previous autotopisms. Moreover, it is proven that every substructure given by the isotopism class of a Latin square is a 1-(v,k,r) design. Since the corresponding parameter k is known for Latin squares of order up to 7, we obtain the rest of the parameters of all these substructures and, consequently, a classification of all possible symmetries is reached for these orders.

Latin squares have been historically used in order to create statistical designs in which, starting from a small number of experiments, it can be obtained a large experimental space. In this sense, the optimization of the selection of Latin squares can be decisive. A factor to take into account is the symmetry that the experimental space must verify and which is established by the autotopism group of each Latin square. Although the size of this group is known for Latin squares of order up to 10, a classification of the different symmetries has not yet been done. In this paper, given a cycle structure of a Latin square autotopism, it is studied the regularity of the incidence structure formed by the set of autotopisms having this cycle structure and the set of Latin squares remaining stable by at least one of the previous autotopisms. Moreover, it is proven that every substructure given by the isotopism class of a Latin square is a 1-(v,k,r) design. Since the corresponding parameter k is known for Latin squares of order up to 7, we obtain the rest of the parameters of all these substructures and, consequently, a classification of all possible symmetries is reached for these orders.

Latin squares have been historically used in order to create statistical designs in which, starting from a small number of experiments, it can be obtained a large experimental space. In this sense, the optimization of the selection of Latin squares can be decisive. A factor to take into account is the symmetry that the experimental space must verify and which is established by the autotopism group of each Latin square. Although the size of this group is known for Latin squares of order up to 10, a classification of the different symmetries has not yet been done. In this paper, given a cycle structure of a Latin square autotopism, it is studied the regularity of the incidence structure formed by the set of autotopisms having this cycle structure and the set of Latin squares remaining stable by at least one of the previous autotopisms. Moreover, it is proven that every substructure given by the isotopism class of a Latin square is a 1-(v,k,r) design. Since the corresponding parameter k is known for Latin squares of order up to 7, we obtain the rest of the parameters of all these substructures and, consequently, a classification of all possible symmetries is reached for these orders.

Androgens have been linked to visuospatial ability. We examined the relationship between serum free testosterone (T) levels and spatial visualization ability in a population-based sample of 450 healthy men between the ages of 35 and 80 years. They were tested on block design and Mini Mental State of Examination (MMSE) draw-a-figure, as well as tasks assessing episodic memory, semantic memory, procedural memory, and verbal fluency. Blood was analyzed for free T and estradiol. Participants were grouped into high or low free T based on age-specific median values. Participants with low free T performed at a superior level on both the block design task and draw-a-figure task as compared to participants with high free T. The results are discussed within the scant body of research on androgens and cognition in men.

Aging pattern in WAIS-R Block Design test (BDT) performance were examined cross-sectionally and longitudinally. One sample (35-80 years, n = 1000) was assessed in 1988-1990 and five years later (836 returned). An independent cohort-matched sample (n = 974) was included at Time 2 to estimate the magnitude of practice effects. Relations between BDT performance, gender, and education were also examined. The cross-sectional analyses indicated a gradual age-related deterioration from 35 to 55, even when minor practice effects were adjusted for. Decline was apparent for the older cohorts, regardless of estimation method. Education-adjusted cross-sectional differences showed a similar pattern. A minor age- and time-invariant gender difference favoring males was observed. Education predicted some time-related change, such as higher education was associated with lesser decline. Collectively, the results demonstrate the nedd to control for cohort and retest effects in cross-sectional and longitudinal studies, and reveal interesting relations between BDT performance and demographic variables.

Recently, different types of composite floor slabs have been developed and used in the construction industry worldwide. These floor slabs are developed to cater for the shortcomings that are observed in the existing floor slabs. Some of these shortcomings are: long construction time, heavy weight and, bad thermal and sound barrier. All these shortcomings are dependant on the heavy equipment on job site and on formwork and the jointing problems. Ferrocement-Brick composite slab is one of the recent developments in composite slab systems. The composite is a semi-precast floor slab system which consists of an inverted ribbed ferrocement layer interlocked with bricks used in situ concrete ribs. Aerated autoclaved concrete (AAC) blocks are used, instead of bricks, in a ferrocement-brick composite. The blocks provides a very light weight material ( =6 kN/m3), effective thermal insulation and sound barrier compared to normal bricks. Using the aerated autoclaved concrete block will lead to 30% reduction in the weight of the slab compared to the reinforced concrete slab. This study aims at investigating the structural behaviour of ferrocement-AAC block composite floor slab under flexural loading focusing on the effect of different AAC block layouts in the composite slab on the structural performance of the composite slab. Nine full-scale ferrocement-block composite slabs of different block layouts are cast and tested experimentally under two-point loads. In addition, three ferrocement layers are tested to identify their capabilities to carry the construction loads. The structural performance of the composite slabs is investigated in terms of their deformation and ductility characteristics, cracking characteristics, strain distribution and failure mechanism. The AAC block layouts play a significant role in the structural behaviour of the ferrocement-AAC block composite slab. It is also concluded that the interlocking mechanism is capable of connecting the two layers and the s

Recently, different types of composite floor slabs have been developed and used in the construction industry worldwide. These floor slabs are developed to cater for the shortcomings that are observed in the existing floor slabs. Some of these shortcomings are: long construction time, heavy weight and, bad thermal and sound barrier. All these shortcomings are dependant on the heavy equipment on job site and on formwork and the jointing problems. Ferrocement-Brick composite slab is one of the recent developments in composite slab systems. The composite is a semi-precast floor slab system which consists of an inverted ribbed ferrocement layer interlocked with bricks used in situ concrete ribs. Aerated autoclaved concrete (AAC) blocks are used, instead of bricks, in a ferrocement-brick composite. The blocks provides a very light weight material ( =6 kN/m3), effective thermal insulation and sound barrier compared to normal bricks. Using the aerated autoclaved concrete block will lead to 30% reduction in the weight of the slab compared to the reinforced concrete slab. This study aims at investigating the structural behaviour of ferrocement-AAC block composite floor slab under flexural loading focusing on the effect of different AAC block layouts in the composite slab on the structural performance of the composite slab. Nine full-scale ferrocement-block composite slabs of different block layouts are cast and tested experimentally under two-point loads. In addition, three ferrocement layers are tested to identify their capabilities to carry the construction loads. The structural performance of the composite slabs is investigated in terms of their deformation and ductility characteristics, cracking characteristics, strain distribution and failure mechanism. The AAC block layouts play a significant role in the structural behaviour of the ferrocement-AAC block composite slab. It is also concluded that the interlocking mechanism is capable of connecting the two layers and the s

Five-year changes in episodic and semantic memory were examined in a sample of 829 participants (35-80 years). A cohort-matched sample (N=967) was assessed to control for practice effects. For episodic memory, cross-sectional analyses indicated gradual age-related decrements, whereas the longitudinal data revealed no decrements before age 60, even when practice effects were adjusted for. Longitudinally, semantic memory showed minor increments until age 55, with smaller decrements in old age as compared with episodic memory. Cohort differences in educational attainment appear to account for the discrepancies between cross-sectional and longitudinal data. Collectively, the results show that age trajectories for episodic and semantic memory differ and underscore the need to control for cohort and retest effects in cross-sectional and longitudinal studies, respectively.

2 - (v,k,1)設計的自同構群的傳遞性強烈地影響著設計的結構 ,Buekenbout等人在 2 - (v,k,1)設計有旗傳遞自同構群的假設下幾乎決定出所有可能的設計 .此后人們轉而研究具有區組傳遞的自同構群的設計 .我們證明了 ,若一個 2 - (v,k,1)設計 D有一個自同構群 G在 D上區組傳遞、點本原 ,且 G的基柱為交錯群 ,則 D為 2元域上 3維射影空間而 G=A7或 A8. The transitivity of the automorphism group of a 2- (v, k, 1) design heavily restricts the structure of the design. Buekenhout et al. determined almost all possible 2- (v, k, 1) designs, of which the automorphism group act flag-transitively on them. After that people devote their attention to the designs with block-transitive automorphism groups. It is proved that if the automorphism group G of a 2- (v, k, 1) design D acts block-transitively and point-primitively on D and the socle of G is an alternation group, then D is the projective geometry of dimension 3 over GF (2) and G≌A 7 or A 8.

This document considers the problem of comparing test treatments with a control in a proper block design. The auther derives sufficient conditions for the A-optimality of both R-type and S-type designs, and demonstrates how these conditions can be used to obtain families of optimal designs. He gives an example for the construction of the desired S-type designs. A table with optimal R-type designs (3 or = k or = 10, k or = v or = 30) is also given.

The problem of obtaining A optimal designs for comparing v test treatments with a control in b blocks of size k each is considered. A step type design is a BTIB design in which the control is replicated t times in some blocks and t + 1 times in the remaining blocks. A condition on the parameters (v,b,k) is identified for which optimal step type designs can be obtained. Families of such designs are given. Methods for searching for highly efficient designs are proposed, for situations where it is difficult to determine an A optimal design.

A method for the construction of a rectangular geometric dual from a Deltahedron based maximally planar adjacency graph is given along with its computer implementation. In addition, a method and its computer implementation for the addition of areas to form a block plan is given. Comparisons with output from other computer methods is included. Possible extensions include the construction of a rectangular geometric dual with areas for all maximally planar and adjacency graphs.

This paper studies the class of augmented balanced incomplete block designs, which are used for comparing a control treatment with a set of test treatments. Under the A criterion a condition is established that enables us to determine the most efficient augmented design and we suggest some methods to compute a lower bound for the efficiency of these designs. For 3 or = k or = k the parameters of the most efficient designs with a lower bound for their efficiency or, if known, mention their optimality.

There is a vast literature on the construction of orthogonal single replicate factorial designs in incomplete blocks. The reader is referred to Voss for the list of references. The concept of deletion designs was introduced in Kishen and Srivastava. The deletion technique in deletion designs was then used by many authors. This article considers deletion designs in three incomplete blocks and then presents a systematic method for finding the u.e. (unbiasedly estimable) and n.u.e. (not unbiasedly estimable) factorial effects. For n.u.e. factorial effects, the biased estimators (biased w.r.t block effects) are called the unadjusted estimators. Under the assumption that certain higher order interactions are negligible, the unbiased estimation of block effects contrasts and n.u.e. factorial effects, excluding the general mean, are possible. This makes the deletion design an orthogonal design. The unbiased estimators of n.u. e. factorial effects under the assumption are called the adjusted estimators. The relative efficiency in the estimation of a factorial effect is the ratio of the variance of the unadjusted estimator divided by the variance of the adjusted estimator.

This article is concerned with the analysis of experiments arranged in blocks chosen at random. Estimates of the polynomial parameters in the associated response surface model are obtained free of blocks. Tests concerning the polynomial and random block effects are presented. Furthermore, the power of the test for the block effect is obtained using a certain approximation by Hirotsu (1979). A numerical example is given to illustrate the implementation of the proposed analysis. Keywords: Design moments; Fixed and random effects; Mixed model; Orthogonal blocking; Polynomial and block effects; Response surface model.

For certain number of treatments, v, it is impossible to form a reduced BIB design in blocks of size k. Based on the necessary conditions vr = bk and lambda (v-1) = r(k-1) which must hold in any BIB (v,b,r,k, lambda) design, it is shown that v = 8 and k = 3 is the only case for which no reduced BIB design can be constructed if k > 2. A table of BIB designs for v = 8 and k = 3 with support sizes from 22 to 56 is provided., Prepared in cooperation with California Univ., Berkeley. Dept. of Statistics.

A block-structured solution scheme is developed for the analysis of three-dimensional transonic flows. The scheme is based on the solution of potential flow equations for individual blocks representing part of the flow field. Based on a previously developed block-structured grid generation scheme, appropriate computational grids are generated for each of the blocks depending on the complexity of the local flow field. The equations are then solved to provide a solution of a large problem in terms of an assembly of smaller problems for each block. Numerical results illustrate the applicability of the method for a three-dimensional flow field around a wing profile (NACA0012). Different block structures are analyzed to demonstrate the robustness and the accuracy of the developed method. Finally a three-dimensional wing-body configuration is analyzed and the results are compared with previously obtained single block solutions. The method is expandable to the solution of Euler and Navier-Stokes equations. It is also suited to be executed in a parallel processing environment. Keywords: Finite Element Method; Transonic Flow, Three Dimensional Flow; Potential Flow.

A-optimal designs for comparing v test treatments with a control in b blocks of size k each are considered. 111 such designs are given when the parameters are in the range: 2 or = k or = 8, k or = v or = 30, v or = b or = 50. (Author)

The set of distinct blocks of a block design is known as its support. We construct a BIB design with parameters V or = 7, k = 3, lambda = v - 2 which contains a block of maximal multiplicity and has support (V/3) - 4(v-3). Any BIB design which contains such a block and has parameters as above must be supported on at most (V/3) - 4(v-3) blocks. (Author)

It is shown that among binary and connected block designs with and without equal block sizes and equal replications only a symmetric balanced incomplete block design produces a completely symmetric information matrix for the treatment effects whenever the number of blocks is equal to the number of treatments and the number of experimental units is a multiple of the number of treatments. This result contains a known result as a special case.