1,560 research outputs found
Medial Temporal Lobe Does Not Tell The Whole Story: Episodic Memory In ‘atypical’ Variants Of Alzheimer’s Disease
Alzheimer’s disease is the most common form of dementia, which is globally epidemic and well-known by the general public. Episodic memory, a conscious recollection of a particular event in spatial and temporal context, is the most prominent deficit in the early stage of clinical amnestic AD, and reflected by the shrinkage of structures in medial temporal lobe (MTL), including the hippocampus. According to Braak staging, tangles begin in the transentorhinal cortex of the MTL, which then spreads to hippocampal subfields, and later to neocortical areas. Cases that are less recognized by the general public are patients with the atypical variants of AD. Interestingly, many of the atypical cases of AD appear to share the same histopathological features with clinical amnestic AD. According to the diagnostic criteria for these atypical variants of AD, episodic memory should be relatively preserved. However, inconsistent reports on the episodic memory performance and the hippocampal involvement in these atypical cases pose challenges for accurately diagnosing these patients. The two kinds of atypical variants of AD that I focused here are logopenic variant of Primary Progressive Aphasia (lvPPA) and posterior cortical atrophy (PCA). The overarching theme of my thesis is to examine 1) whether the atypical cases of AD have episodic memory difficulty, and if so, 2) what brain areas are responsible for this difficulty. Chapter 2 and 3 of the current thesis show that 1) episodic memory difficulty is observed in lvPPA and PCA cases and 2) this impairment is modulated by deficit in other cognitive domains and associated with disease in non-MTL brain regions. This would be consistent with the ‘hippocampal-sparing’ hypothesis that not all AD histopathology begins in the MTL, and these hippocampal-sparing conditions suggest that additional mechanisms must be considered in the genesis of spreading pathology in AD
Declines in swimming performance with age: a longitudinal study of Masters swimming champions.
IntroductionBecause of its many participants and thorough records, competitive Masters swimming offers a rich data source for determining the rate of physical decline associated with aging in physically fit individuals. The decline in performance among national champion swimmers, both men and women and in short and long swims, is linear, at about 0.6% per year up to age 70-75, after which it accelerates in quadratic fashion. These conclusions are based primarily on cross-sectional studies, and little is known about individual performance declines with aging. Herein we present performance profiles of 19 male and 26 female national and international champion Masters swimmers, ages 25 to 96 years, participating in competitions for an average of 23 years.Methods and resultsSwimmers' longitudinal data were compared with the fastest times of world record holders across ages 35-100 years by two regression methods. Neither method proved to accurately model this data set: compared with the rates of decline estimated from the world record data, which represent the best recorded times at given ages, there was bias toward shallower rates of performance decline in the longitudinal data, likely owing to a practice effect in some swimmers as they began their Masters programs. In swimmers' later years, once maximum performance had been achieved, individual profiles followed the decline represented in the world records, and a few swimmers became the world record holders. In some instances, the individual profiles indicated performance better than the world record data; these swimmers achieved their times after the world record data were collected in 2005-2006.ConclusionDeclining physiological functional capacity occurs with advancing age, and this is reflected in the performance decrements of aging Masters swimmers. Individual swimmers show different performance trajectories with aging, declines being mitigated by practice, which improves both physiological capacity and swimming technique, particularly in the early years of participation. The longitudinal data of this study indicate that individuals can participate in high-intensity swimming over several decades, competitively improving over those decades until, in some instances, they become world record holders for their age groups
Group Theory Applications: Infra-red Spectral Assignment
Group theory principles were applied and the transformation of the x, y, z vectors on each atom caused by symmetry operations were observed to obtain the 3N basis vector representations é3N, of NiCl4 , Al2Cl6 and Fe(CO)5. The identified infra-red active modes and Raman active modes were then assigned to the experimental spectral frequencies by using the projection operator method
Poverty among households living in slum area of Hlaing Tharyar Township, Yangon City, Myanmar
Background: Slums can be regarded as physical manifestations of urban poverty. Although the world has made dramatic improvement in reducing poverty since 1990, poverty still persists at an unacceptable level. Although current situations highlights the importance of slum areas to be given priority in poverty alleviation, there are limited data on poverty level among people living in urban slums of Myanmar.Methods: A cross-sectional study was conducted among households living in slum areas of Hlaing Tharyar Township, Yangon City, Myanmar during 2016. Multi-staged systematic random sampling and face-to-face interview were applied in selecting the samples and collecting the data, respectively. The new global poverty line (1.9 USD per person per day) was used as a threshold in determining the poverty. Chi-squared test and multivariate logistic regression analysis were utilized in data analysis.Results: Altogether 254 participants were recruited after getting informed consent. The occurrence of poverty among households was 54.3% (95% CI: 48.2%, 60.5%). Head counts of poverty among study population was 58.8%. The education status of household’s head, size of household and the presence of less than 15 years old children in the household were detected as significant determinants of being poor household.Conclusions: Poverty among households living in slum area of Hlaing Tharyar Township, Yangon City was high. Measures to alleviate poverty in urban slums should be intensified. Education level of household’s heads should be improved. Family planning or birth spacing programme should also be strengthened, especially in urban slums.
Keterkaitan antara Demokrasi Politik, Demokrasi Ekonomi dan Sistem Ekonomi Kerakyatan
Demokrasi politik merupakan syarat bagi berjalannya demokrasi ekonomi. Pelaksanaan demokrasi ekonomi akan terwujud bila terdapat kesejajaran antara sistem politik dan sistem ekonomi. Dalam sejarah perekonomian nasional, semangat demokrasi ekonomi sering dilanggar oleh menjurusnya sistem ekonomi nasional baik ke arah ekonomi kapitalistik atau ke sistem ekonomi terpusat. Sistem ekonomi kerakyatan yang bercirikan penegakan keadilan demokrasi ekonomi dan pemihakan terhadap yang lemah merupakan landasan dan sekaligus sebagai sarana bagi mewujudkan keadilan sosial bagi seluruh rakyat yang merupakan pilar utama demokrasi ekonomi
Keterkaitan antara Demokrasi Politik, Demokrasi Ekonomi dan Sistem Ekonomi Kerakyatan
Demokrasi politik merupakan syarat bagi berjalannya demokrasi ekonomi. Pelaksanaan demokrasi ekonomi akan terwujud bila terdapat kesejajaran antara sistem politik dan sistem ekonomi. Dalam sejarah perekonomian nasional, semangat demokrasi ekonomi sering dilanggar oleh menjurusnya sistem ekonomi nasional baik ke arah ekonomi kapitalistik atau ke sistem ekonomi terpusat. Sistem ekonomi kerakyatan yang bercirikan penegakan keadilan demokrasi ekonomi dan pemihakan terhadap yang lemah merupakan landasan dan sekaligus sebagai sarana bagi mewujudkan keadilan sosial bagi seluruh rakyat yang merupakan pilar utama demokrasi ekonomi
Genetic analysis of Myanmar Vigna species in responses to salt stress at the seedling stage
Twelve (12) Vigna genotypes were investigated for the evaluation of their tolerance levels in responses to four concentrations of NaCl (0, 75, 150 and 225 mM) at seedling stage. In the investigation, salt stress inhibited almost all the growth parameters as well as relative water content; however, the degree of reduction was highly dependent on different genotypes and salinity levels. Generally, the control plants showed higher degree of all measured parameters than those of salt stress plants. Analysis of the heredity parameters based on the 12 investigated genotypes showed different genotypic variance of the salt tolerance index (STI) values. Salinity stress induced two new bands between 45 and 22 kDa, respectively, in salt tolerant genotypes. Furthermore, band intensity of the salt treated genotypes was higher than the control plants. Ward’s clustering technique was clearly divided into two clusters, A and B, according to their levels of salt tolerance. Considering their STI values of growth parameters, two genotypes V7 and V4 were identified as salt tolerant, whereas, V2, V6, V9, V8, V11 and V1 were recognized as salinity susceptible genotypes. These results suggest that, the genetically diverseaccessions resistant to salt stresses within the Vigna genotypes can be of considerable practical value for studying the mechanism of salt tolerance and for the provision of genetic resources for salinity breeding program.Key words: Cluster analysis, heritability, salt tolerance, SDS-PAGE, Vigna
An Alternative Electrode System for Monitoring Belousov-Zhabotinsky Chemical Oscillations
The capability of copper-platinum (Cu/Pt) electrode system as a BelousovZhabotinsky (BZ) chemical oscillation monitor was compared with that of the normally used SCE/Pt electrode system, by testing it on three BZ systems, which were obtained by varying the oscillator in the combination bromate, oscillator and malonic acid. The oscillators, used separately, were cerium(IV), manganese(II) and ferroin [iron (II)-1,10- phenanthroline complex].Cu/Pt electrode gave essentially identical values of oscillation characteristics (oscillation period, peak potential, induction period, peak width) except peak potentials. This indicated that the Cu/Pt electrode system would be more useful than the SCE/Pt electrode system (which had chloride leakage problem), in electrical applications of chemical oscillations, such as electrical switches, which would depend only on the on/off frequency
A Potential Model for Chemical Oscillations
Oscillation characteristics: induction period, oscillation period, peak potential, and total oscillation time of Belousov-Zhabotinsky systems, which consisted of bromate - oscillator [Ce4+ or Mn2+ or ferroin] - malonic acid were deter- mined using SCE/Pt and Cu/Pt electrodes. The solution potential requirements for appearance of chemical oscillations were determined by finding the concentra- tion limits of the reactants, bromate and malonic acid, and measuring the corres-ponding solution reduction potentials. A chemical oscillation model was proposed
Australia's national health programs: An ontological mapping
Australia has a large number of health program initiatives whose comprehensive assessment will help refine and redefine priorities by highlighting areas of emphasis, under-emphasis, and non-emphasis. The objectives of our research are to: (a) systematically map all the programs onto an ontological framework, and (b) systemically analyse their relative emphases at different levels of granularity. We mapped all the health program initiatives onto an ontology with five dimensions, namely: (a) Policy-scope, (b) Policy-focus, (c) Outcomes, (d) Type of care, and (e) Population served. Each dimension is expanded into a taxonomy of its constituent elements. Each combination of elements from the five dimensions is a possible policy initiative component. There are 30,030 possible components encapsulated in the ontology. It includes, for example: (a) National financial policies on accessibility of preventive care for family, and (b) Local-urban regulatory policies on cost of palliative care for individual-aged. Four of the authors mapped all of Australia's health programs and initiatives on to the ontology. Visualizations of the data are used to highlight the relative emphases in the program initiatives. The dominant emphasis of the program initiatives is: [National] [educational, personnel-physician, information] policies on [accessibility, quality] of [preventive, wellness] care for the [community]. However, although (a) information is emphasized technology is not and (b) accessibility and quality are emphasized cost, satisfaction, and quality are not. The ontology and the results of the mapping can help systematically reassess and redirect the relative emphases of the programs and initiatives from a systemic perspective
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