Investigation of adaptive filtering and MDL mitigation based on space-time block-coding for spatial division multiplexed coherent receivers

NASA Astrophysics Data System (ADS)

Weng, Yi; He, Xuan; Yao, Wang; Pacheco, Michelle C.; Wang, Junyi; Pan, Zhongqi

2017-07-01

In this paper, we explored the performance of space-time block-coding (STBC) assisted multiple-input multiple-output (MIMO) scheme for modal dispersion and mode-dependent loss (MDL) mitigation in spatial-division multiplexed optical communication systems, whereas the weight matrices of frequency-domain equalization (FDE) were updated heuristically using decision-directed recursive least squares (RLS) algorithm for convergence and channel estimation. The proposed STBC-RLS algorithm can achieve 43.6% enhancement on convergence rate over conventional least mean squares (LMS) for quadrature phase-shift keying (QPSK) signals with merely 16.2% increase in hardware complexity. The overall optical signal to noise ratio (OSNR) tolerance can be improved via STBC by approximately 3.1, 4.9, 7.8 dB for QPSK, 16-quadrature amplitude modulation (QAM) and 64-QAM with respective bit-error-rates (BER) and minimum-mean-square-error (MMSE).

Optimal estimation for discrete time jump processes

NASA Technical Reports Server (NTRS)

Vaca, M. V.; Tretter, S. A.

1977-01-01

Optimum estimates of nonobservable random variables or random processes which influence the rate functions of a discrete time jump process (DTJP) are obtained. The approach is based on the a posteriori probability of a nonobservable event expressed in terms of the a priori probability of that event and of the sample function probability of the DTJP. A general representation for optimum estimates and recursive equations for minimum mean squared error (MMSE) estimates are obtained. MMSE estimates are nonlinear functions of the observations. The problem of estimating the rate of a DTJP when the rate is a random variable with a probability density function of the form cx super K (l-x) super m and show that the MMSE estimates are linear in this case. This class of density functions explains why there are insignificant differences between optimum unconstrained and linear MMSE estimates in a variety of problems.

Optimal estimation for discrete time jump processes

NASA Technical Reports Server (NTRS)

Vaca, M. V.; Tretter, S. A.

1978-01-01

Optimum estimates of nonobservable random variables or random processes which influence the rate functions of a discrete time jump process (DTJP) are derived. The approach used is based on the a posteriori probability of a nonobservable event expressed in terms of the a priori probability of that event and of the sample function probability of the DTJP. Thus a general representation is obtained for optimum estimates, and recursive equations are derived for minimum mean-squared error (MMSE) estimates. In general, MMSE estimates are nonlinear functions of the observations. The problem is considered of estimating the rate of a DTJP when the rate is a random variable with a beta probability density function and the jump amplitudes are binomially distributed. It is shown that the MMSE estimates are linear. The class of beta density functions is rather rich and explains why there are insignificant differences between optimum unconstrained and linear MMSE estimates in a variety of problems.

Optimal design of minimum mean-square error noise reduction algorithms using the simulated annealing technique.

PubMed

Bai, Mingsian R; Hsieh, Ping-Ju; Hur, Kur-Nan

2009-02-01

The performance of the minimum mean-square error noise reduction (MMSE-NR) algorithm in conjunction with time-recursive averaging (TRA) for noise estimation is found to be very sensitive to the choice of two recursion parameters. To address this problem in a more systematic manner, this paper proposes an optimization method to efficiently search the optimal parameters of the MMSE-TRA-NR algorithms. The objective function is based on a regression model, whereas the optimization process is carried out with the simulated annealing algorithm that is well suited for problems with many local optima. Another NR algorithm proposed in the paper employs linear prediction coding as a preprocessor for extracting the correlated portion of human speech. Objective and subjective tests were undertaken to compare the optimized MMSE-TRA-NR algorithm with several conventional NR algorithms. The results of subjective tests were processed by using analysis of variance to justify the statistic significance. A post hoc test, Tukey's Honestly Significant Difference, was conducted to further assess the pairwise difference between the NR algorithms.

A family of chaotic pure analog coding schemes based on baker's map function

NASA Astrophysics Data System (ADS)

Liu, Yang; Li, Jing; Lu, Xuanxuan; Yuen, Chau; Wu, Jun

2015-12-01

This paper considers a family of pure analog coding schemes constructed from dynamic systems which are governed by chaotic functions—baker's map function and its variants. Various decoding methods, including maximum likelihood (ML), minimum mean square error (MMSE), and mixed ML-MMSE decoding algorithms, have been developed for these novel encoding schemes. The proposed mirrored baker's and single-input baker's analog codes perform a balanced protection against the fold error (large distortion) and weak distortion and outperform the classical chaotic analog coding and analog joint source-channel coding schemes in literature. Compared to the conventional digital communication system, where quantization and digital error correction codes are used, the proposed analog coding system has graceful performance evolution, low decoding latency, and no quantization noise. Numerical results show that under the same bandwidth expansion, the proposed analog system outperforms the digital ones over a wide signal-to-noise (SNR) range.

Falls and cognitive decline in Mexican Americans 75 years and older

PubMed Central

Padubidri, Anokha; Al Snih, Soham; Samper-Ternent, Rafael; Markides, Kyriakos S; Ottenbacher, Kenneth J; Raji, Mukaila A

2014-01-01

Background Little is known about long-term emotional and cognitive consequences of falls. We examined the association between falls and subsequent cognitive decline, and tested the hypothesis that depression would mediate any falls–cognition association among cognitively intact Hispanic Elders. Methods We used data from the Hispanic Established Population for the Epidemiological Study of the Elderly to examine change in Mini Mental State Examination (MMSE) scores over the 6-year period according to number of falls. All participants (N=1,119) had MMSE scores ≥21 and complete data on Center for Epidemiologic Studies of Depression Scale, social and demographic factors, medical conditions (diabetes, heart attack, stroke, and hypertension), and hand grip muscle strength. Results At baseline, participants’ mean age was 80.8 years (range, 74–109), mean education was 6.3 years (range, 0–17), and mean MMSE was 25.2 (range, 21–30). Of the 1,119 participants, 15.8% experienced one fall and 14.4% had two or more falls. In mixed model analyses, having two or more falls was associated with greater decline in MMSE score (estimate =−0.81, standard error =0.19, P<0.0001) compared to having no fall, after adjusting for age, sex, marital status, and education. The magnitude of the association decreased (estimate =−0.65, standard error =0.19, P=0.0007) when adjustment was made for high depressive symptoms, suggesting a possible mediating effect of depression on the falls–cognition association. Female sex, high level of education, and high performance in hand grip muscle strength were associated with a slower decline in MMSE scores. Conclusion Having two or more falls was independently associated with steeper decline in cognition over 6 years, with a possible mediating effect of depression on the falls–cognition association. PMID:24790424

Channel estimation in few mode fiber mode division multiplexing transmission system

NASA Astrophysics Data System (ADS)

Hei, Yongqiang; Li, Li; Li, Wentao; Li, Xiaohui; Shi, Guangming

2018-03-01

It is abundantly clear that obtaining the channel state information (CSI) is of great importance for the equalization and detection in coherence receivers. However, to the best of the authors' knowledge, in most of the existing literatures, CSI is assumed to be perfectly known at the receiver. So far, few literature discusses the effects of imperfect CSI on MDM system performance caused by channel estimation. Motivated by that, in this paper, the channel estimation in few mode fiber (FMF) mode division multiplexing (MDM) system is investigated, in which two classical channel estimation methods, i.e., least square (LS) method and minimum mean square error (MMSE) method, are discussed with the assumption of the spatially white noise lumped at the receiver side of MDM system. Both the capacity and BER performance of MDM system affected by mode-dependent gain or loss (MDL) with different channel estimation errors have been studied. Simulation results show that the capacity and BER performance can be further deteriorated in MDM system by the channel estimation, and an 1e-3 variance of channel estimation error is acceptable in MDM system with 0-6 dB MDL values.

Iterative MMSE Detection for MIMO/BLAST DS-CDMA Systems in Frequency Selective Fading Channels - Achieving High Performance in Fully Loaded Systems

NASA Astrophysics Data System (ADS)

Silva, João Carlos; Souto, Nuno; Cercas, Francisco; Dinis, Rui

A MMSE (Minimum Mean Square Error) DS-CDMA (Direct Sequence-Code Division Multiple Access) receiver coupled with a low-complexity iterative interference suppression algorithm was devised for a MIMO/BLAST (Multiple Input, Multiple Output / Bell Laboratories Layered Space Time) system in order to improve system performance, considering frequency selective fading channels. The scheme is compared against the simple MMSE receiver, for both QPSK and 16QAM modulations, under SISO (Single Input, Single Output) and MIMO systems, the latter with 2Tx by 2Rx and 4Tx by 4Rx (MIMO order 2 and 4 respectively) antennas. To assess its performance in an existing system, the uncoded UMTS HSDPA (High Speed Downlink Packet Access) standard was considered.

Validation of the Conversion between the Mini-Mental State Examination and Montreal Cognitive assessment in Korean Patients with Parkinson’s Disease

PubMed Central

Kim, Ryul; Kim, Han-Joon; Kim, Aryun; Jang, Mi-Hee; Kim, Hyun Jeong; Jeon, Beomseok

2018-01-01

Objective Two conversion tables between the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) have recently been established for Parkinson’s disease (PD). This study aimed to validate them in Korean patients with PD and to evaluate whether they could be influenced by educational level. Methods A total of 391 patients with PD who undertook both the Korean MMSE and the Korean MoCA during the same session were retrospectively assessed. The mean, median, and root mean squared error (RMSE) of the difference between the true and converted MMSE scores and the intraclass correlation coefficient (ICC) were calculated according to educational level (6 or fewer years, 7–12 years, or 13 or more years). Results Both conversions had a median value of 0, with a small mean and RMSE of differences, and a high correlation between the true and converted MMSE scores. In the classification according to educational level, all groups had roughly similar values of the median, mean, RMSE, and ICC both within and between the conversions. Conclusion Our findings suggest that both MMSE-MoCA conversion tables are useful instruments for transforming MoCA scores into converted MMSE scores in Korean patients with PD, regardless of educational level. These will greatly enhance the utility of the existing cognitive data from the Korean PD population in clinical and research settings. PMID:29316782

Cognitive function and dementia in six areas of England and Wales: the distribution of MMSE and prevalence of GMS organicity level in the MRC CFA Study. The Medical Research Council Cognitive Function and Ageing Study (MRC CFAS).

PubMed

1998-03-01

This two-stage prevalence survey involved geographically delimited areas, four urban (Liverpool, Newcastle, Nottingham and Oxford) and two rural (Cambridgeshire and Gwynedd), including institutions. Stratified random population samples of people in their 65th year and above, from Family Health Service Authorities were studied. The sample was stratified (65-74 years and > or = 75) to provide equal numbers. In Liverpool equal numbers in 5 year age groups were taken. After an initial screening interview, approximately 20% were selected on the basis of age, AGECAT organicity confidence level and MMSE score to proceed to a detailed assessment interview from which the full AGECAT organicity confidence level could be derived. Major influences on MMSE were confirmed as age, sex, social class and educational level. Estimates of prevalence of AGECAT O3 and above for each centre and the entire sample according to age are given, based on 1991 Census population structure, and suggest that around half a million (543,400) people in England and Wales would be defined as case level by this method. The five centres employing the same methodology showed no heterogeneity in prevalence. Prevalence of cognitive impairment and dementia appear not to vary widely across the centres examined in this study, which provides stable estimates by age and sex for AGECAT O3 and above, and norms for MMSE. Using these estimates as an indication of the size of the population affected, around 550,000 individuals in England and Wales would be expected to be suffering from dementia of mild or greater severity.

The relationship between education level and Mini Mental State Examination domains among older Mexican Americans

PubMed Central

Matallana, Diana; de Santacruz, Cecilia; Cano, Carlos; Reyes, Pablo; Samper-Ternent, Rafael; Markides, Kyriakos S.; Ottenbacher, Kenneth J.; Reyes-Ortiz, Carlos A.

2011-01-01

To study the effect of education on the performance in the Mini-Mental State Examination (MMSE) domains, we included 2,861 Mexican Americans aged 65 and older from the Hispanic Established Populations for Epidemiologic Studies of the Elderly (EPESE) followed from 1993–1994 until 2004–2005. The MMSE was examined as total score (0–30) or divided in two global domains: 1) no-memory (score 0–24): Orientation, attention, and language; and 2) memory (score 0–6): working and delayed memory. Mean age and total MMSE were 72.7 and 24.6 at wave 1, and 81.7 and 20.5 at wave 5. Spanish speaking subjects had lower years of education (4.1 vs. 7.4, p<.0001), they had significantly higher adjusted (by age, education, and gender) mean scores for memory, no-memory and the total MMSE compared with English speaking subjects across the five waves of follow-up. In multivariate longitudinal analyses over 11 years of follow-up, subjects with more years of education performed better than those less educated, especially in no-memory and the total MMSE. Spanish speaking subjects with 4–6 years of education had higher memory scores than those speaking English (estimate 0.40, standard error [SE] = 0.14, p<.001), 7–11 (estimate 0.27, SE= 0.13, p<.01) or 12+ (estimate 0.44, SE= 0.13, p<.001). This suggests that cultural factors and factors related to preferred language use may determine variations in MMSE performance. Since the memory domain of the MMSE is less affected by education, it may be used along with other cognitive tests in older populations with low education. PMID:20538969

A Practical, Hardware Friendly MMSE Detector for MIMO-OFDM-Based Systems

NASA Astrophysics Data System (ADS)

Kim, Hun Seok; Zhu, Weijun; Bhatia, Jatin; Mohammed, Karim; Shah, Anish; Daneshrad, Babak

2008-12-01

Design and implementation of a highly optimized MIMO (multiple-input multiple-output) detector requires cooptimization of the algorithm with the underlying hardware architecture. Special attention must be paid to application requirements such as throughput, latency, and resource constraints. In this work, we focus on a highly optimized matrix inversion free [InlineEquation not available: see fulltext.] MMSE (minimum mean square error) MIMO detector implementation. The work has resulted in a real-time field-programmable gate array-based implementation (FPGA-) on a Xilinx Virtex-2 6000 using only 9003 logic slices, 66 multipliers, and 24 Block RAMs (less than 33% of the overall resources of this part). The design delivers over 420 Mbps sustained throughput with a small 2.77-microsecond latency. The designed [InlineEquation not available: see fulltext.] linear MMSE MIMO detector is capable of complying with the proposed IEEE 802.11n standard.

Color discrimination performance in patients with Alzheimer's disease.

PubMed

Salamone, Giovanna; Di Lorenzo, Concetta; Mosti, Serena; Lupo, Federica; Cravello, Luca; Palmer, Katie; Musicco, Massimo; Caltagirone, Carlo

2009-01-01

Visual deficits are frequent in Alzheimer's disease (AD), yet little is known about the nature of these disturbances. The aim of the present study was to investigate color discrimination in patients with AD to determine whether impairment of this visual function is a cognitive or perceptive/sensory disturbance. A cross-sectional clinical study was conducted in a specialized dementia unit on 20 patients with mild/moderate AD and 21 age-matched normal controls. Color discrimination was measured by the Farnsworth-Munsell 100 hue test. Cognitive functioning was measured with the Mini-Mental State Examination (MMSE) and a comprehensive battery of neuropsychological tests. The scores obtained on the color discrimination test were compared between AD patients and controls adjusting for global and domain-specific cognitive performance. Color discrimination performance was inversely related to MMSE score. AD patients had a higher number of errors in color discrimination than controls (mean +/- SD total error score: 442.4 +/- 84.5 vs. 304.1 +/- 45.9). This trend persisted even after adjustment for MMSE score and cognitive performance on specific cognitive domains. A specific reduction of color discrimination capacity is present in AD patients. This deficit does not solely depend upon cognitive impairment, and involvement of the primary visual cortex and/or retinal ganglionar cells may be contributory.

Space-Time Joint Interference Cancellation Using Fuzzy-Inference-Based Adaptive Filtering Techniques in Frequency-Selective Multipath Channels

NASA Astrophysics Data System (ADS)

Hu, Chia-Chang; Lin, Hsuan-Yu; Chen, Yu-Fan; Wen, Jyh-Horng

2006-12-01

An adaptive minimum mean-square error (MMSE) array receiver based on the fuzzy-logic recursive least-squares (RLS) algorithm is developed for asynchronous DS-CDMA interference suppression in the presence of frequency-selective multipath fading. This receiver employs a fuzzy-logic control mechanism to perform the nonlinear mapping of the squared error and squared error variation, denoted by ([InlineEquation not available: see fulltext.],[InlineEquation not available: see fulltext.]), into a forgetting factor[InlineEquation not available: see fulltext.]. For the real-time applicability, a computationally efficient version of the proposed receiver is derived based on the least-mean-square (LMS) algorithm using the fuzzy-inference-controlled step-size[InlineEquation not available: see fulltext.]. This receiver is capable of providing both fast convergence/tracking capability as well as small steady-state misadjustment as compared with conventional LMS- and RLS-based MMSE DS-CDMA receivers. Simulations show that the fuzzy-logic LMS and RLS algorithms outperform, respectively, other variable step-size LMS (VSS-LMS) and variable forgetting factor RLS (VFF-RLS) algorithms at least 3 dB and 1.5 dB in bit-error-rate (BER) for multipath fading channels.

Diagnostic performance of short portable mental status questionnaire for screening dementia among patients attending cognitive assessment clinics in Singapore.

PubMed

Malhotra, Chetna; Chan, Angelique; Matchar, David; Seow, Dennis; Chuo, Adeline; Do, Young Kyung

2013-07-01

The Short Portable Mental Status Questionnaire (SPMSQ) is a brief cognitive screening instrument, which is easy to use by a healthcare worker with little training. However, the validity of this instrument has not been established in Singapore. Thus, the primary aim of this study was to determine the diagnostic performance of SPMSQ for screening dementia among patients attending outpatient cognitive assessment clinics and to assess whether the appropriate cut-off score varies by patient's age and education. A secondary aim of the study was to map the SPMSQ scores with Mini-Mental State Examination (MMSE) scores. SPMSQ and MMSE were administered by a trained interviewer to 127 patients visiting outpatient cognitive assessment clinics at the Singapore General Hospital, Changi General Hospital and Tan Tock Seng Hospital. The geriatricians at these clinics then diagnosed these patients with dementia or no dementia (reference standard). Sensitivity and specificity of SPMSQ with different cut-off points (number of errors) were calculated and compared to the reference standard using the Receiver Operator Characteristic (ROC) analysis. Correlation coefficient was also calculated between MMSE and SPMSQ scores. Based on the ROC analysis and a balance of sensitivity and specificity, the appropriate cut-off for SPMSQ was found to be 5 or more errors (sensitivity 78%, specificity 75%). The cut-off varied by education, but not by patient's age. There was a high correlation between SPMSQ and MMSE scores (r = 0.814, P <0.0001). Despite the advantage of being a brief screening instrument for dementia, the use of SPMSQ is limited by its low sensitivity and specificity, especially among patients with less than 6 years of education.

A study on the achievable data rate in massive MIMO system

NASA Astrophysics Data System (ADS)

Salh, Adeeb; Audah, Lukman; Shah, Nor Shahida M.; Hamzah, Shipun A.

2017-09-01

The achievable high data rates depend on the ability of massive multi-input-multi-output (MIMO) for the fifth-generation (5G) cellular networks, where the massive MIMO systems can support very high energy and spectral efficiencies. A major challenge in mobile broadband networks is how to support the throughput in the future 5G, where the highlight of 5G expected to provide high speed internet for every user. The performance massive MIMO system increase with linear minimum mean square error (MMSE), zero forcing (ZF) and maximum ratio transmission (MRT) when the number of antennas increases to infinity, by deriving the closed-form approximation for achievable data rate expressions. Meanwhile, the high signal-to-noise ratio (SNR) can be mitigated by using MMSE, ZF and MRT, which are used to suppress the inter-cell interference signals between neighboring cells. The achievable sum rate for MMSE is improved based on the distributed users inside cell, mitigated the inter-cell interference caused when send the same signal by other cells. By contrast, MMSE is better than ZF in perfect channel state information (CSI) for approximately 20% of the achievable sum rate.

MMSE Estimator for Children’s Speech with Car and Weather Noise

NASA Astrophysics Data System (ADS)

Sayuthi, V.

2018-04-01

Previous research mentioned that most people need and use vehicles for various purposes, in this recent time and future, as a means of traveling. Many ways can be done in a vehicle, such as for enjoying entertainment, and doing work, so vehicles not just only as a means of traveling. In this study, we will examine the children’s speech from a girl in the vehicle that affected by noise disturbances from the sound source of car noise and the weather sound noise around it, in this case, the rainy weather noise. Vehicle sounds may be from car engine or car air conditioner. The minimum mean square error (MMSE) estimator is used as an attempt to obtain or detect the children’s clear speech by representing simulation research as random process signal that factored by the autocorrelation of both the child’s voice and the disturbance noise signal. This MMSE estimator can be considered as wiener filter as the clear sound are reconstructed again. We expected that the results of this study can help as the basis for development of entertainment or communication technology for passengers of vehicles in the future, particularly using MMSE estimators.

Development of Super-Ensemble techniques for ocean analyses: the Mediterranean Sea case

NASA Astrophysics Data System (ADS)

Pistoia, Jenny; Pinardi, Nadia; Oddo, Paolo; Collins, Matthew; Korres, Gerasimos; Drillet, Yann

2017-04-01

Short-term ocean analyses for Sea Surface Temperature SST in the Mediterranean Sea can be improved by a statistical post-processing technique, called super-ensemble. This technique consists in a multi-linear regression algorithm applied to a Multi-Physics Multi-Model Super-Ensemble (MMSE) dataset, a collection of different operational forecasting analyses together with ad-hoc simulations produced by modifying selected numerical model parameterizations. A new linear regression algorithm based on Empirical Orthogonal Function filtering techniques is capable to prevent overfitting problems, even if best performances are achieved when we add correlation to the super-ensemble structure using a simple spatial filter applied after the linear regression. Our outcomes show that super-ensemble performances depend on the selection of an unbiased operator and the length of the learning period, but the quality of the generating MMSE dataset has the largest impact on the MMSE analysis Root Mean Square Error (RMSE) evaluated with respect to observed satellite SST. Lower RMSE analysis estimates result from the following choices: 15 days training period, an overconfident MMSE dataset (a subset with the higher quality ensemble members), and the least square algorithm being filtered a posteriori.

Handling missing Mini-Mental State Examination (MMSE) values: Results from a cross-sectional long-term-care study.

PubMed

Godin, Judith; Keefe, Janice; Andrew, Melissa K

2017-04-01

Missing values are commonly encountered on the Mini Mental State Examination (MMSE), particularly when administered to frail older people. This presents challenges for MMSE scoring in research settings. We sought to describe missingness in MMSEs administered in long-term-care facilities (LTCF) and to compare and contrast approaches to dealing with missing items. As part of the Care and Construction project in Nova Scotia, Canada, LTCF residents completed an MMSE. Different methods of dealing with missing values (e.g., use of raw scores, raw scores/number of items attempted, scale-level multiple imputation [MI], and blended approaches) are compared to item-level MI. The MMSE was administered to 320 residents living in 23 LTCF. The sample was predominately female (73%), and 38% of participants were aged >85 years. At least one item was missing from 122 (38.2%) of the MMSEs. Data were not Missing Completely at Random (MCAR), χ 2 (1110) = 1,351, p < 0.001. Using raw scores for those missing <6 items in combination with scale-level MI resulted in the regression coefficients and standard errors closest to item-level MI. Patterns of missing items often suggest systematic problems, such as trouble with manual dexterity, literacy, or visual impairment. While these observations may be relatively easy to take into account in clinical settings, non-random missingness presents challenges for research and must be considered in statistical analyses. We present suggestions for dealing with missing MMSE data based on the extent of missingness and the goal of analyses. Copyright © 2016 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

Screening an elderly hearing impaired population for mild cognitive impairment using Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA).

PubMed

Lim, Magdalene Yeok Leng; Loo, Jenny Hooi Yin

2018-07-01

To determine if there is an association between hearing loss and poorer cognitive scores on Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) and to determine if poor hearing acuity affects scoring on the cognitive screening tests of MMSE and MoCA. One hundred fourteen elderly patients (Singapore residents) aged between 55 and 86 years were sampled. Participants completed a brief history questionnaire, pure tone audiometry, and 2 cognitive screening tests-the MMSE and MoCA. Average hearing thresholds of the better ear in the frequencies of 0.5, 1, 2, and 4 kHz were used for data analysis. Hearing loss was significantly associated with poorer cognitive scores in Poisson regression models adjusted for age. Mini-Mental State Examination scores were shown to decrease by 2.8% (P = .029), and MoCA scores by 3.5% (P = .013) for every 10 dB of hearing loss. Analysis of hearing-sensitive components of "Registration" and "Recall" in MMSE and MoCA using chi-square tests showed significantly poorer performance in the hearing loss group as compared to the normal hearing group. Phonetic analysis of target words with high error rates shows that the poor performance was likely contributed by decreased hearing acuity, on top of a possible true deficit in cognition in the hearing impaired. Hearing loss is associated with poorer cognitive scores on MMSE and MoCA, and cognitive scoring is likely confounded by poor hearing ability. This highlights an important, often overlooked aspect of sensory impairment during cognitive screening. Provisions should be made when testing for cognition in the hearing-impaired population to avoid over-referral and subsequent misdiagnoses of cognitive impairment. Copyright © 2018 John Wiley & Sons, Ltd.

Time-of-flight PET image reconstruction using origin ensembles.

PubMed

Wülker, Christian; Sitek, Arkadiusz; Prevrhal, Sven

2015-03-07

The origin ensemble (OE) algorithm is a novel statistical method for minimum-mean-square-error (MMSE) reconstruction of emission tomography data. This method allows one to perform reconstruction entirely in the image domain, i.e. without the use of forward and backprojection operations. We have investigated the OE algorithm in the context of list-mode (LM) time-of-flight (TOF) PET reconstruction. In this paper, we provide a general introduction to MMSE reconstruction, and a statistically rigorous derivation of the OE algorithm. We show how to efficiently incorporate TOF information into the reconstruction process, and how to correct for random coincidences and scattered events. To examine the feasibility of LM-TOF MMSE reconstruction with the OE algorithm, we applied MMSE-OE and standard maximum-likelihood expectation-maximization (ML-EM) reconstruction to LM-TOF phantom data with a count number typically registered in clinical PET examinations. We analyzed the convergence behavior of the OE algorithm, and compared reconstruction time and image quality to that of the EM algorithm. In summary, during the reconstruction process, MMSE-OE contrast recovery (CRV) remained approximately the same, while background variability (BV) gradually decreased with an increasing number of OE iterations. The final MMSE-OE images exhibited lower BV and a slightly lower CRV than the corresponding ML-EM images. The reconstruction time of the OE algorithm was approximately 1.3 times longer. At the same time, the OE algorithm can inherently provide a comprehensive statistical characterization of the acquired data. This characterization can be utilized for further data processing, e.g. in kinetic analysis and image registration, making the OE algorithm a promising approach in a variety of applications.

Time-of-flight PET image reconstruction using origin ensembles

NASA Astrophysics Data System (ADS)

Wülker, Christian; Sitek, Arkadiusz; Prevrhal, Sven

2015-03-01

The origin ensemble (OE) algorithm is a novel statistical method for minimum-mean-square-error (MMSE) reconstruction of emission tomography data. This method allows one to perform reconstruction entirely in the image domain, i.e. without the use of forward and backprojection operations. We have investigated the OE algorithm in the context of list-mode (LM) time-of-flight (TOF) PET reconstruction. In this paper, we provide a general introduction to MMSE reconstruction, and a statistically rigorous derivation of the OE algorithm. We show how to efficiently incorporate TOF information into the reconstruction process, and how to correct for random coincidences and scattered events. To examine the feasibility of LM-TOF MMSE reconstruction with the OE algorithm, we applied MMSE-OE and standard maximum-likelihood expectation-maximization (ML-EM) reconstruction to LM-TOF phantom data with a count number typically registered in clinical PET examinations. We analyzed the convergence behavior of the OE algorithm, and compared reconstruction time and image quality to that of the EM algorithm. In summary, during the reconstruction process, MMSE-OE contrast recovery (CRV) remained approximately the same, while background variability (BV) gradually decreased with an increasing number of OE iterations. The final MMSE-OE images exhibited lower BV and a slightly lower CRV than the corresponding ML-EM images. The reconstruction time of the OE algorithm was approximately 1.3 times longer. At the same time, the OE algorithm can inherently provide a comprehensive statistical characterization of the acquired data. This characterization can be utilized for further data processing, e.g. in kinetic analysis and image registration, making the OE algorithm a promising approach in a variety of applications.

MMSE and MoCA in Parkinson’s disease and dementia with Lewy bodies: a multicenter 1-year follow-up study

PubMed Central

Weis, L.; Bostantjopoulou, S.; Stefanova, E.; Falup-Pecurariu, C.; Kramberger, M. G.; Geurtsen, G. J.; Antonini, A.; Weintraub, D.; Aarsland, D.

2016-01-01

The Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) are the most commonly used scales to test cognitive impairment in Lewy body disease (LBD), but there is no consensus on which is best suited to assess cognition in clinical practice and most sensitive to cognitive decline. Retrospective cohort study of 265 LBD patients [Parkinson’s disease (PD) without dementia (PDnD, N = 197), PD with dementia (PDD, N = 40), and dementia with Lewy bodies (DLB, N = 28)] from an international consortium who completed both the MMSE and MoCA at baseline and 1-year follow-up (N = 153). Percentage of relative standard deviation (RSD%) at baseline was the measure of inter-individual variance, and estimation of change (Cohen’s d) over time was calculated. RSD% for the MoCA (21 %) was greater than for the MMSE (13 %) (p = 0.03) in the whole group. This difference was significant only in PDnD (11 vs. 5 %, p < 0.01), but not in PDD (30 vs. 19 %, p = 0.37) or DLB (15 vs. 14 %, p = 0.78). In contrast, the 1-year estimation of change did not differ between the two tests in any of the groups (Cohen’s effect <0.20 in each group). MMSE and MoCA are equal in measuring the rate of cognitive changes over time in LBD. However, in PDnD, the MoCA is a better measure of cognitive status as it lacks both ceiling and floor effects. PMID:26852137

Tracking with time-delayed data in multisensor systems

NASA Astrophysics Data System (ADS)

Hilton, Richard D.; Martin, David A.; Blair, William D.

1993-08-01

When techniques for target tracking are expanded to make use of multiple sensors in a multiplatform system, the possibility of time delayed data becomes a reality. When a discrete-time Kalman filter is applied and some of the data entering the filter are delayed, proper processing of these late data is a necessity for obtaining an optimal estimate of a target's state. If this problem is not given special care, the quality of the state estimates can be degraded relative to that quality provided by a single sensor. A negative-time update technique is developed using the criteria of minimum mean-square error (MMSE) under the constraint that only the results of the most recent update are saved. The performance of the MMSE technique is compared to that of the ad hoc approach employed in the Cooperative Engagement Capabilities (CEC) system for processing data from multiple platforms. It was discovered that the MMSE technique is a stable solution to the negative-time update problem, while the CEC technique was found to be less than desirable when used with filters designed for tracking highly maneuvering targets at relatively low data rates. The MMSE negative-time update technique was found to be a superior alternative to the existing CEC negative-time update technique.

Three-dimensional holoscopic image coding scheme using high-efficiency video coding with kernel-based minimum mean-square-error estimation

NASA Astrophysics Data System (ADS)

Liu, Deyang; An, Ping; Ma, Ran; Yang, Chao; Shen, Liquan; Li, Kai

2016-07-01

Three-dimensional (3-D) holoscopic imaging, also known as integral imaging, light field imaging, or plenoptic imaging, can provide natural and fatigue-free 3-D visualization. However, a large amount of data is required to represent the 3-D holoscopic content. Therefore, efficient coding schemes for this particular type of image are needed. A 3-D holoscopic image coding scheme with kernel-based minimum mean square error (MMSE) estimation is proposed. In the proposed scheme, the coding block is predicted by an MMSE estimator under statistical modeling. In order to obtain the signal statistical behavior, kernel density estimation (KDE) is utilized to estimate the probability density function of the statistical modeling. As bandwidth estimation (BE) is a key issue in the KDE problem, we also propose a BE method based on kernel trick. The experimental results demonstrate that the proposed scheme can achieve a better rate-distortion performance and a better visual rendering quality.

Effects of Transient Versus Chronic Loneliness on Cognitive Function in Older Adults: Findings From the Chinese Longitudinal Healthy Longevity Survey.

PubMed

Zhong, Bao-Liang; Chen, Shu-Lin; Conwell, Yeates

2016-05-01

Loneliness is a risk factor for poor cognitive function in older adults (OAs); to date, however, no studies have explored whether transient and chronic loneliness have differential effects on OAs' cognitive function. The present study evaluates the impacts of transient versus chronic loneliness on cognitive function in OAs. A 6-year follow-up cohort study. Rural and urban communities of 22 provinces in China. 2,995 OAs who were cognitively healthy (the modified Mini-Mental State Examination [mMMSE] ≥ 14) and completed the 2005, 2008, and 2011 waves of the Chinese Longitudinal Healthy Longevity Survey. Self-report loneliness and mMMSE. Both transient (β = -0.389, t = -2.191, df = 2994, p = 0.029) and chronic loneliness (β = -0.640, t = -2.109, df = 2994, p = 0.035) were significantly associated with lower mMMSE scores 6 years later, net of potential confounding effects of baseline covariates. Sensitivity analyses found that regression coefficients of mMMSE scores on transient loneliness were statistically significant and relatively stable across samples with various levels of cognitive function. In contrast, coefficients of mMMSE scores on chronic loneliness were statistically significant only among samples with normal cognitive function and the absolute values of these coefficients increased with the degree of cognitive health of the analytic sample. In the sample with mMMSE greater than or equal to 21, the coefficient of chronic loneliness was 2.59 times as large as that of transient loneliness (-1.017 versus -0.392). Both transient and chronic loneliness are significant predictors of cognitive decline in OAs. Relative to transient loneliness, chronic loneliness has more pronounced negative effects on the brain health of OAs. Copyright © 2016 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

Performance Evaluation of MIMO-UWB Systems Using Measured Propagation Data and Proposal of Timing Control Scheme in LOS Environments

NASA Astrophysics Data System (ADS)

Takanashi, Masaki; Nishimura, Toshihiko; Ogawa, Yasutaka; Ohgane, Takeo

Ultrawide-band impulse radio (UWB-IR) technology and multiple-input multiple-output (MIMO) systems have attracted interest regarding their use in next-generation high-speed radio communication. We have studied the use of MIMO ultrawide-band (MIMO-UWB) systems to enable higher-speed radio communication. We used frequency-domain equalization based on the minimum mean square error criterion (MMSE-FDE) to reduce intersymbol interference (ISI) and co-channel interference (CCI) in MIMO-UWB systems. Because UWB systems are expected to be used for short-range wireless communication, MIMO-UWB systems will usually operate in line-of-sight (LOS) environments and direct waves will be received at the receiver side. Direct waves have high power and cause high correlations between antennas in such environments. Thus, it is thought that direct waves will adversely affect the performance of spatial filtering and equalization techniques used to enhance signal detection. To examine the feasibility of MIMO-UWB systems, we conducted MIMO-UWB system propagation measurements in LOS environments. From the measurements, we found that the arrival time of direct waves from different transmitting antennas depends on the MIMO configuration. Because we can obtain high power from the direct waves, direct wave reception is critical for maximizing transmission performance. In this paper, we present our measurement results, and propose a way to improve performance using a method of transmit (Tx) and receive (Rx) timing control. We evaluate the bit error rate (BER) performance for this form of timing control using measured channel data.

Modeling the Atmospheric Phase Effects of a Digital Antenna Array Communications System

NASA Technical Reports Server (NTRS)

Tkacenko, A.

2006-01-01

In an antenna array system such as that used in the Deep Space Network (DSN) for satellite communication, it is often necessary to account for the effects due to the atmosphere. Typically, the atmosphere induces amplitude and phase fluctuations on the transmitted downlink signal that invalidate the assumed stationarity of the signal model. The degree to which these perturbations affect the stationarity of the model depends both on parameters of the atmosphere, including wind speed and turbulence strength, and on parameters of the communication system, such as the sampling rate used. In this article, we focus on modeling the atmospheric phase fluctuations in a digital antenna array communications system. Based on a continuous-time statistical model for the atmospheric phase effects, we show how to obtain a related discrete-time model based on sampling the continuous-time process. The effects of the nonstationarity of the resulting signal model are investigated using the sample matrix inversion (SMI) algorithm for minimum mean-squared error (MMSE) equalization of the received signal

End-stage dementia spark of life: reliability and validity of the "GATOS" questionnaire.

PubMed

Tsoucalas, Gregory; Bourelia, Stamati; Kalogirou, Vaso; Giatsiou, Styliani; Mavrogiannaki, Eirini; Gatos, Georgios; Galanos, Antonis; Repana, Olga; Iliadou, Eleni; Antoniou, Antonis; Sgantzos, Markos; Gatos, Konstantinos

2015-01-01

Fl oor effects are present in most dementia assessment tools as dementia progresses and the in-depth assessment of patients considered more or less on vegetative state is questionable. To develop a questionnaire (the "Gatos Clinical Test-GCT") for the assessment of end-stage demented patients. Five hundred patients with dementia of various causes and an MMSE score between 0 and 2 were enrolled in the study. The GCT consists of 14 closed type questions rated on a Likert scale. The total score is used to evaluate patient's dementia. Various aspects of validity and reliability (including face, content and structural validity as well as test-retest reliability) were examined. Three subscales "Autonomy/Alertness", "Gnosias" and "Somatokinetic function" were defined, with a Cronbach equal to 0.851, 0.756 and 0.598 respectively. The GCT subscales and total score were statistically significant higher in patients with MMSE score 1 or 2 compared with those with MMSE score 0 (p<0.0005). Patients with GCT total score less than 12.5 had 75% probability to have zero MMSE score. The "GATOS" questionnaire is a valid and reliable test for patients with severe dementia, aiming at identification of those patients who could sustain some quality of life. It is a relatively short and easy to administer tool. As dementia prevalence is expected to rise further worldwide we believe that GCT could offer valuable services to health professionals, caregivers and patients.

Application of the clinical version of the narrow path walking test to identify elderly fallers.

PubMed

Gimmon, Yoav; Barash, Avi; Debi, Ronen; Snir, Yoram; Bar David, Yair; Grinshpon, Jacob; Melzer, Itshak

2016-01-01

Falling during walking is a common problem among the older population. Hence, the challenge facing clinicians is identifying who is at risk of falling during walking, for providing an effective intervention to reduce that risk. We aimed to assess whether the clinical version of the narrow path walking test (NPWT) could identify older adults who are reported falls. A total of 160 older adults were recruited and asked to recall fall events during the past year. Subjects were instructed to walk in the laboratory at a comfortable pace within a 6 meter long narrow path, 3 trials under single task (ST) and 3 trials dual task (DT) conditions without stepping outside the path (i.e., step errors). The average trial time, number of steps, trial velocity, number of step errors, and number of cognitive task errors were calculated for ST and DT. Fear of falling, performance oriented mobility assessment (POMA) and mini-metal state examination (MMSE) were measured as well. Sixty-one subjects reported that they had fallen during the past year and 99 did not. Fallers performed more steps, and were slower than non-fallers. There were no significant differences, however, in the number of steps errors, the cognitive task errors in ST and DT in POMA and MMSE. Our data demonstrates slower gait speed and more steps during the NPWT in ST and DT in fallers. There is no added value of DT over the ST for identification of faller's older adults. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Advanced diffraction-based overlay for double patterning

NASA Astrophysics Data System (ADS)

Li, Jie; Liu, Yongdong; Dasari, Prasad; Hu, Jiangtao; Smith, Nigel; Kritsun, Oleg; Volkman, Catherine

2010-03-01

Diffraction based overlay (DBO) technologies have been developed to address the tighter overlay control challenges as the dimensions of integrated circuit continue to shrink. Several studies published recently have demonstrated that the performance of DBO technologies has the potential to meet the overlay metrology budget for 22nm technology node. However, several hurdles must be cleared before DBO can be used in production. One of the major hurdles is that most DBO technologies require specially designed targets that consist of multiple measurement pads, which consume too much space and increase measurement time. A more advanced spectroscopic ellipsometry (SE) technology-Mueller Matrix SE (MM-SE) is developed to address the challenge. We use a double patterning sample to demonstrate the potential of MM-SE as a DBO candidate. Sample matrix (the matrix that describes the effects of the sample on the incident optical beam) obtained from MM-SE contains up to 16 elements. We show that the Mueller elements from the off-diagonal 2x2 blocks respond to overlay linearly and are zero when overlay errors are absent. This superior property enables empirical DBO (eDBO) using two pads per direction. Furthermore, the rich information in Mueller matrix and its direct response to overlay make it feasible to extract overlay errors from only one pad per direction using modeling approach (mDBO). We here present the Mueller overlay results using both eDBO and mDBO and compare the results with image-based overlay (IBO) and CD-SEM results. We also report the tool induced shifts (TIS) and dynamic repeatability.

The Montreal Cognitive Assessment and the mini-mental state examination as screening instruments for cognitive impairment: item analyses and threshold scores.

PubMed

Damian, Anne M; Jacobson, Sandra A; Hentz, Joseph G; Belden, Christine M; Shill, Holly A; Sabbagh, Marwan N; Caviness, John N; Adler, Charles H

2011-01-01

To perform an item analysis of the Montreal Cognitive Assessment (MoCA) versus the Mini-Mental State Examination (MMSE) in the prediction of cognitive impairment, and to examine the characteristics of different MoCA threshold scores. 135 subjects enrolled in a longitudinal clinicopathologic study were administered the MoCA by a single physician and the MMSE by a trained research assistant. Subjects were classified as cognitively impaired or cognitively normal based on independent neuropsychological testing. 89 subjects were found to be cognitively normal, and 46 cognitively impaired (20 with dementia, 26 with mild cognitive impairment). The MoCA was superior in both sensitivity and specificity to the MMSE, although not all MoCA tasks were of equal predictive value. A MoCA threshold score of 26 had a sensitivity of 98% and a specificity of 52% in this population. In a population with a 20% prevalence of cognitive impairment, a threshold of 24 was optimal (negative predictive value 96%, positive predictive value 47%). This analysis suggests the potential for creating an abbreviated MoCA. For screening in primary care, the MoCA threshold of 26 appears optimal. For testing in a memory disorders clinic, a lower threshold has better predictive value. Copyright © 2011 S. Karger AG, Basel.

Norms of the Mini-Mental state Examination for Japanese subjects that underwent comprehensive brain examinations: the Kashima Scan Study.

PubMed

Yakushiji, Yusuke; Horikawa, Etsuo; Eriguchi, Makoto; Nanri, Yusuke; Nishihara, Masashi; Hirotsu, Tatsumi; Hara, Hideo

2014-01-01

The distribution of the Mini-Mental State Examination (MMSE) scores by age and educational level was investigated in subjects that underwent comprehensive brain examinations. This cross-sectional study included 1,414 adults without neurological disorders who underwent health-screening tests of the brain, referred to as the "Brain Dock," in our center. The MMSE scores were compared between age groups (40-44, 45-49, 50-54, 55-59, 60-64, 65-69, or ≥70 years) and educational levels [the low education level group (6-12 years) and the high education level group (≥13 years)]. The median age was 59 years, and 763 (54%) were women. There was no significant difference in the MMSE total score between women and men. The stepwise method of the multiple linear regression analysis confirmed that a higher age [β value, -0.129; standard error (S.E.), 0.020; p<0.001], low education level (6-12 years) (β value, -0.226; S.E., 0.075; p=0.003), and women (β values, 0.148; S.E., 0.066; p=0.024) was significantly associated with decreased MMSE score. In general, both the percentile scores and mean scores decreased with aging and were lower in the low education level group than in the high education level group. The degree of decrement in scores with age was stronger in the low education level group than in the high education level group. The provided data for age- and education-specific reference norms will be useful for both clinicians and investigators who perform comprehensive brain examinations to assess the cognitive function of subjects.

Rigorous study of low-complexity adaptive space-time block-coded MIMO receivers in high-speed mode multiplexed fiber-optic transmission links using few-mode fibers

NASA Astrophysics Data System (ADS)

Weng, Yi; He, Xuan; Wang, Junyi; Pan, Zhongqi

2017-01-01

Spatial-division multiplexing (SDM) techniques have been purposed to increase the capacity of optical fiber transmission links by utilizing multicore fibers or few-mode fibers (FMF). The most challenging impairments of SDMbased long-haul optical links mainly include modal dispersion and mode-dependent loss (MDL), whereas MDL arises from inline component imperfections, and breaks modal orthogonality thus degrading the capacity of multiple-inputmultiple- output (MIMO) receivers. To reduce MDL, optical approaches include mode scramblers and specialty fiber designs, yet these methods were burdened with high cost, yet cannot completely remove the accumulated MDL in the link. Besides, space-time trellis codes (STTC) were purposed to lessen MDL, but suffered from high complexity. In this work, we investigated the performance of space-time block-coding (STBC) scheme to mitigate MDL in SDM-based optical communication by exploiting space and delay diversity, whereas weight matrices of frequency-domain equalization (FDE) were updated heuristically using decision-directed recursive-least-squares (RLS) algorithm for convergence and channel estimation. The STBC was evaluated in a six-mode multiplexed system over 30-km FMF via 6×6 MIMO FDE, with modal gain offset 3 dB, core refractive index 1.49, numerical aperture 0.5. Results show that optical-signal-to-noise ratio (OSNR) tolerance can be improved via STBC by approximately 3.1, 4.9, 7.8 dB for QPSK, 16- and 64-QAM with respective bit-error-rates (BER) and minimum-mean-square-error (MMSE). Besides, we also evaluate the complexity optimization of STBC decoding scheme with zero-forcing decision feedback (ZFDF) equalizer by shortening the coding slot length, which is robust to frequency-selective fading channels, and can be scaled up for SDM systems with more dynamic channels.

Three screening methods for cognitive dysfunction using the Mini-Mental State Examination and Korean Dementia Screening Questionnaire.

PubMed

Choi, Seong Hye; Park, Moon Ho

2016-02-01

To screen for and determine cognitive dysfunction, cognitive tests and/or informant reports are commonly used. However, these cognitive tests and informant reports are not always available. The present study investigated three screening methods using the Mini-Mental State Examination (MMSE) as the cognitive test, and the Korean dementia screening questionnaire (KDSQ) as the informant report. Participants were recruited from the Korea Clinical Research Center for Dementia of South Korea, and included 2861 patients with Alzheimer's disease (dementia), 3519 patients with mild cognitive impairment and 1375 controls with no cognitive dysfunction. Three screening methods were tested: (i) MMSE alone (MMSE(cut-off) ); (ii) a conventional combination of MMSE and KDSQ (MMSE+KDSQ(cut-off) ); and (iii) a decision tree with MMSE and KDSQ (MMSE+KDSQ(decision tree) ). For discriminating any cognitive dysfunction from controls, MMSE+KDSQ(cut-off) had the highest area under the receiver operating characteristic curve (0.784). For discriminating dementia from controls, MMSE+KDSQ(cut-off) had the highest area under the receiver operating characteristic curve (0.899). For discriminating mild cognitive impairment from controls, MMSE(cut-off) had the highest area under the receiver operating characteristic curve (0.683). MMSE+KDSQ(decision tree) showed the highest sensitivity for all discriminations. For overall classification accuracy, MMSE+KDSQ(decision tree) had the highest value (70.0%). These three methods had different advantageous properties for screening and staging cognitive dysfunction. As there might be different availability across clinical settings, these three methods can be selected and used according to situational needs. © 2015 Japan Geriatrics Society.

The MMSE orientation for time domain is a strong predictor of subsequent cognitive decline in the elderly.

PubMed

Guerrero-Berroa, Elizabeth; Luo, Xiaodong; Schmeidler, James; Rapp, Michael A; Dahlman, Karen; Grossman, Hillel T; Haroutunian, Vahram; Beeri, Michal Schnaider

2009-12-01

The mini-mental state exam (MMSE) has been used to address questions such as determination of appropriate cutoff scores for differentiation of individuals with intact cognitive function from patients with dementia and rate of cognitive decline. However, little is known about the relationship of performance in specific cognitive domains to subsequent overall decline. To examine the specific and/or combined contribution of four MMSE domains (orientation for time, orientation for place, delayed recall, and attention) to prediction of overall cognitive decline on the MMSE. Linear mixed models were applied to 505 elderly nursing home residents (mean age = 85, > 12 years education = 27%; 79% F, mean follow-up = 3.20 years) to examine the relationship between baseline scores of these domains and total MMSE scores over time. Orientation for time was the only domain significantly associated with MMSE decline over time. Combination of poor delayed recall with either attention or orientation for place was associated with significantly increased decline on the MMSE. The MMSE orientation for time predicts overall decline on MMSE scores over time. A good functioning domain added to good functioning delayed recall was associated with slower rate of decline. Copyright (c) 2009 John Wiley & Sons, Ltd.

Performance analysis of adaptive equalization for coherent acoustic communications in the time-varying ocean environment.

PubMed

Preisig, James C

2005-07-01

Equations are derived for analyzing the performance of channel estimate based equalizers. The performance is characterized in terms of the mean squared soft decision error (sigma2(s)) of each equalizer. This error is decomposed into two components. These are the minimum achievable error (sigma2(0)) and the excess error (sigma2(e)). The former is the soft decision error that would be realized by the equalizer if the filter coefficient calculation were based upon perfect knowledge of the channel impulse response and statistics of the interfering noise field. The latter is the additional soft decision error that is realized due to errors in the estimates of these channel parameters. These expressions accurately predict the equalizer errors observed in the processing of experimental data by a channel estimate based decision feedback equalizer (DFE) and a passive time-reversal equalizer. Further expressions are presented that allow equalizer performance to be predicted given the scattering function of the acoustic channel. The analysis using these expressions yields insights into the features of surface scattering that most significantly impact equalizer performance in shallow water environments and motivates the implementation of a DFE that is robust with respect to channel estimation errors.

Clinical utility of the mini-mental status examination when assessing decision-making capacity.

PubMed

Pachet, Arlin; Astner, Kevin; Brown, Lenora

2010-03-01

The main objectives of this study were to examine the relationship between cognitive deficits, as measured by the Mini-Mental Status Examination (MMSE), and decision-making capacity and to determine whether the sensitivity and specificity of the MMSE varied based upon the patient population assessed. Using a sample size of 152 patients and varying cutoff scores, the MMSE demonstrated extremely poor sensitivity. In contrast, the MMSE had excellent specificity when scores of 19 or less were obtained. In our sample, not one patient, regardless of diagnosis, was deemed to have capacity if their MMSE score was below 20. However, reliance on the MMSE for scores above 19 would too frequently lead to misclassification and incorrect assumptions about a patient's decision-making abilities. Although a score below 20 consistently yielded findings of incapability in our sample, it remains our opinion that the MMSE should not be used as a stand-alone tool to make determinations related to capacity, especially when considering the complexities associated with capacity evaluations and the vital areas, such as executive functioning and individual values and beliefs, which are omitted by the MMSE.

Conversion of the Mini-Mental State Examination to the International Classification of Functioning, Disability and Health terminology and scoring system.

PubMed

De Vriendt, P; Gorus, E; Bautmans, I; Mets, T

2012-01-01

In older patients, evaluation of the cognitive status is crucial. The Mini-Mental State Examination (MMSE) is widely used for screening of cognition, providing fairly high sensitivity, specificity and reproducibility. Recently, a consensus emerged on the necessity of an international and transparent language, as provided by the WHO's International Classification of Functioning, Disability and Health (ICF). Most assessment tools however are not in accordance with the ICF. To reformulate the MMSE according to the ICF, both for the individual items and for the scoring system. MMSE data (scores varying from 3 to 30/30) of (1) 217 cognitively healthy elderly, (2) 60 persons with mild cognitive impairment, (3) 60 patients with mild Alzheimer's disease (AD), and (4) 60 patients with moderate/severe AD were obtained from studies at a university hospital setting. Subjects were aged 65 years or more and recruited either through advertisement (group 1), from the geriatric day hospital (groups 2 and 3), or the geriatric ward (group 4). The allocation to the groups was done after multidisciplinary evaluation. The conversion of the MMSE to ICF-MMSE was done by content comparison and by subsequent translation of the scoring system using automatic algorithms. All MMSE items were converted to the corresponding ICF categories. Three ICF domains were addressed: global and specific mental functions, general tasks and demands, divided over 6 ICF categories (orientation time/place, sustaining attention, memory functions, mental functions of language, undertaking a simple task). Scores on individual items were transformed according to their relative weight on the original MMSE scale, and a total ICF-MMSE score from 0 (no problem) to 100 (complete problem) was generated. Translation was satisfying, as illustrated by a good correlation between MMSE and ICF-MMSE. The diagnostic groups were distributed over the ICF-MMSE scores as expected. For each ICF domain, ICF-MMSE subscores were higher with increasing severity in cognitive decline. There was a higher dispersion, in accordance with the more detailed scoring possibilities of the ICF-MMSE. It is possible to adapt the MMSE to the ICF concept. This adaptation enhances interdisciplinary communication since it provides more clarity in assessment, with better visibility of the areas covered by the instrument. Copyright © 2011 S. Karger AG, Basel.

The Influence of Noise Reduction on Speech Intelligibility, Response Times to Speech, and Perceived Listening Effort in Normal-Hearing Listeners.

PubMed

van den Tillaart-Haverkate, Maj; de Ronde-Brons, Inge; Dreschler, Wouter A; Houben, Rolph

2017-01-01

Single-microphone noise reduction leads to subjective benefit, but not to objective improvements in speech intelligibility. We investigated whether response times (RTs) provide an objective measure of the benefit of noise reduction and whether the effect of noise reduction is reflected in rated listening effort. Twelve normal-hearing participants listened to digit triplets that were either unprocessed or processed with one of two noise-reduction algorithms: an ideal binary mask (IBM) and a more realistic minimum mean square error estimator (MMSE). For each of these three processing conditions, we measured (a) speech intelligibility, (b) RTs on two different tasks (identification of the last digit and arithmetic summation of the first and last digit), and (c) subjective listening effort ratings. All measurements were performed at four signal-to-noise ratios (SNRs): -5, 0, +5, and +∞ dB. Speech intelligibility was high (>97% correct) for all conditions. A significant decrease in response time, relative to the unprocessed condition, was found for both IBM and MMSE for the arithmetic but not the identification task. Listening effort ratings were significantly lower for IBM than for MMSE and unprocessed speech in noise. We conclude that RT for an arithmetic task can provide an objective measure of the benefit of noise reduction. For young normal-hearing listeners, both ideal and realistic noise reduction can reduce RTs at SNRs where speech intelligibility is close to 100%. Ideal noise reduction can also reduce perceived listening effort.

Increased Muscle Sympathetic Nerve Activity and Impaired Executive Performance Capacity in Obstructive Sleep Apnea.

PubMed

Goya, Thiago T; Silva, Rosyvaldo F; Guerra, Renan S; Lima, Marta F; Barbosa, Eline R F; Cunha, Paulo Jannuzzi; Lobo, Denise M L; Buchpiguel, Carlos A; Busatto-Filho, Geraldo; Negrão, Carlos E; Lorenzi-Filho, Geraldo; Ueno-Pardi, Linda M

2016-01-01

To investigate muscle sympathetic nerve activity (MSNA) response and executive performance during mental stress in obstructive sleep apnea (OSA). Individuals with no other comorbidities (age = 52 ± 1 y, body mass index = 29 ± 0.4, kg/m2) were divided into two groups: (1) control (n = 15) and (2) untreated OSA (n = 20) defined by polysomnography. Mini-Mental State of Examination (MMSE) and Inteligence quocient (IQ) were assessed. Heart rate (HR), blood pressure (BP), and MSNA (microneurography) were measured at baseline and during 3 min of the Stroop Color Word Test (SCWT). Sustained attention and inhibitory control were assessed by the number of correct answers and errors during SCWT. Control and OSA groups (apnea-hypopnea index, AHI = 8 ± 1 and 47 ± 1 events/h, respectively) were similar in age, MMSE, and IQ. Baseline HR and BP were similar and increased similarly during SCWT in control and OSA groups. In contrast, baseline MSNA was higher in OSA compared to controls. Moreover, MSNA significantly increased in the third minute of SCWT in OSA, but remained unchanged in controls (P < 0.05). The number of correct answers was lower and the number of errors was significantly higher during the second and third minutes of SCWT in the OSA group (P < 0.05). There was a significant correlation (P < 0.01) between the number of errors in the third minute of SCWT with AHI (r = 0.59), arousal index (r = 0.55), and minimum O2 saturation (r = -0.57). As compared to controls, MSNA is increased in patients with OSA at rest, and further significant MSNA increments and worse executive performance are seen during mental stress. URL: http://www.clinicaltrials.gov, registration number: NCT002289625. © 2016 Associated Professional Sleep Societies, LLC.

[Cost relation between severity of Alzheimer's disease and cognitive and functional impairment].

PubMed

López-Pousa, Secundino; Garre-Olmo, Josep; Turon-Estrada, Antoni; Hernández, Francisco; Expósito, Inmaculada; Lozano-Gallego, Manoli; Hernández-Ferrándiz, Marta; Gelada-Batlle, Esther; Pericot-Nierga, Imma; Vilalta-Franch, Joan

2004-05-29

This study aims to identify the relationship between costs of medical and social attention in patients with dementia of Alzheimer disease (AD) type and clinical and sociodemographic data of patients and their caregivers. It was an analytic observational study in a cohort of patients diagnosed with Alzheimer's disease who received ambulatory attention. Information about the use of health-related resources was collected and costs were estimated from a societal perspective. Indirect costs were calculated using a replacement cost approach. Patients and caregivers were examined with the Mini-Mental State Examination (MMSE), the Rapid Disability Rating Scale (RDRS-2), the Neuropsychiatric Inventory (NPI), the Burden Interview (BI) and the Resource Utilization in Dementia (RUD). Patients were grouped taking into account the score obtained in the MMSE. A cohort of 417 patients, mean age (SD) 75.2 (6.6) years, 71% females, was studied. Disease severity levels were distributed as follows: MMSE, 26% for MMSE > 19, 66% for MMSE = 19-11, and 8% for MMSE < 11. 69% of caregivers were women, with a mean age of 57.1 (15.8) years. The cost per patient and per month was estimated to be 419.3 Euro for MMSE > 19, 641.9 Euro for MMSE = 19-11, and 1150.6 Euro for MMSE < 11. The societal cost of AD increases dramatically with increasing disease severity. Caregiver burden and sex as well as the marital status of patients are associated with the cost of the disease.

Mini-Mental Status Examination: mixed Rasch model item analysis derived two different cognitive dimensions of the MMSE.

PubMed

Schultz-Larsen, Kirsten; Kreiner, Svend; Lomholt, Rikke Kirstine

2007-03-01

This study published in two companion papers assesses properties of the Mini-Mental State Examination (MMSE) with the purpose of improving the efficiencies of the methods of screening for cognitive impairment and dementia. An item analysis by conventional and mixed Rasch models was used to explore empirically derived cognitive dimensions of the MMSE, to assess item bias, and to construct diagnostic cut-points. The scores of 1,189 elderly residents were analyzed. Two dimensions of cognitive function, which are statistically and conceptually different from those obtained in previous studies, were derived. The corresponding sum scales were (1) age-correlated MMSE scale (A-MMSE scale: orientation to time, attention/calculation, naming, repetition, and three-stage command) and (2) non-age-correlated MMSE scale (B-MMSE scale: orientation to place, registration, recall, reading, and copying). The "writing" item was not included due to differential effects of age and sex. The analysis also showed that the study sample consisted of two cognitively different groups of elderly. The findings indicate that a two-scale solution is a stable and statistically supported framework for interpreting data obtained by means of the MMSE. Supplementary analyses are presented in the companion paper to explore the performance of this item response theory calibration as a screening test for dementia.

A Longitudinal Study of the Mini-Mental State Examination in Late Nonagenarians and Its Relationship with Dementia, Mortality, and Education.

PubMed

Skoog, Johan; Backman, Kristoffer; Ribbe, Mats; Falk, Hanna; Gudmundsson, Pia; Thorvaldsson, Valgeir; Borjesson-Hanson, Anne; Ostling, Svante; Johansson, Boo; Skoog, Ingmar

2017-06-01

To examine level of and change in cognitive status using the Mini-Mental State Examination (MMSE) in relation to dementia, mortality, education, and sex in late nonagenarians. Three-year longitudinal study with examinations at ages 97, 99, and 100. Trained psychiatric research nurses examined participants at their place of living. A representative population-based sample of 97-year-old Swedes (N = 591; 107 men, 484 women) living in Gothenburg, Sweden. A Swedish version of the MMSE was used to measure cognitive status. Geriatric psychiatrists diagnosed dementia according to the Diagnostic and Statistical Manual of Mental Disorders, Third Edition, Revised. Mixed models were fitted to the data to model the longitudinal relationship between MMSE score and explanatory variables. Individuals with dementia between age 97 and 100 had lower mean MMSE scores than those without dementia. Those who died during the 3-year follow-up had lower MMSE scores than those who survived. MMSE scores at baseline did not differ between those without dementia and those who developed dementia during the 3-year follow-up. Participants with more education had higher MMSE scores, but there was no association between education and linear change. MMSE score is associated with dementia and subsequent mortality even in very old individuals, although the preclinical phase of dementia may be short in older age. Level of education is positively associated with MMSE score but not rate of decline in individuals approaching age 100. © 2017, Copyright the Authors Journal compilation © 2017, The American Geriatrics Society.

Study of Mini-Mental State Exam evolution in community-dwelling subjects aged over 60 years without dementia.

PubMed

Watfa, G; Husson, N; Buatois, S; Laurain, M C; Miget, P; Benetos, A

2011-12-01

In recent years, the Mini-Mental State Examination (MMSE) has been widely used and has been proposed for cognitive decline screening in the framework of a systematic geriatric evaluation in health centers. The aim of the present longitudinal study was to identify the potential determinants of MMSE score and its evolution over a 4-year period in a population aged over sixty years with good general health without dementia and consulting for a health check-up. Longitudinal study. The preventive medical center (CMP) in Nancy. 687 subjects over 60 years of age (mean age 65.6 ± 5.07 years) were included from the Senior health examination study. All subjects underwent 2 visits over a period of 4 years. MMSE measurement and a self-administered questionnaire of emotional and psychological state were evaluated at baseline and at the follow-up visit. The major components of total variance of baseline MMSE were represented by education level, practice of regular physical activity, nervousness and despair. Multivariate analysis identified 3 variables at baseline visit that independently predicted annual changes in MMSE: MMSE score, education level and "Difficulty in social relations" (r= -0.222, 0.154 and -0.255 respectively). Education level and several psychological factors may influence MMSE score and its evolution over time in community-dwelling subjects aged over 60 years without dementia. In these subjects, a low MMSE score does not predict cognitive decline over a period of 4 years. Therefore, the reliability of MMSE in this type of population is questionable.

Cognition and quality of life after chemotherapy plus radiotherapy (RT) vs. RT for pure and mixed anaplastic oligodendrogliomas: radiation therapy oncology group trial 9402.

PubMed

Wang, Meihua; Cairncross, Gregory; Shaw, Edward; Jenkins, Robert; Scheithauer, Bernd; Brachman, David; Buckner, Jan; Fink, Karen; Souhami, Luis; Laperriere, Normand; Mehta, Minesh; Curran, Walter

2010-07-01

Radiation Therapy Oncology Group 9402 compared procarbazine, lomustine, and vincristine (PCV) chemotherapy plus radiation therapy (PCV + RT) vs. RT alone for anaplastic oligodendroglioma. Here we report longitudinal changes in cognition and quality of life, effects of patient factors and treatments on cognition, quality of life and survival, and prognostic implications of cognition and quality of life. Cognition was assessed by Mini Mental Status Examination (MMSE) and quality of life by Brain-Quality of Life (B-QOL). Scores were analyzed for survivors and within 5 years of death. Shared parameter models evaluated MMSE/B-QOL with survival. For survivors, MMSE and B-QOL scores were similar longitudinally and between treatments. For those who died, MMSE scores remained stable initially, whereas B-QOL slowly declined; both declined rapidly in the last year of life and similarly between arms. In the aggregate, scores decreased over time (p = 0.0413 for MMSE; p = 0.0016 for B-QOL) and were superior with age <50 years (p < 0.001 for MMSE; p = 0.0554 for B-QOL) and Karnofsky Performance Score (KPS) 80-100 (p < 0.001). Younger age and higher KPS were associated with longer survival. After adjusting for patient factors and drop-out, survival was longer after PCV + RT (HR = 0.66, 95% CI = 0.49-0.9, p = 0.0084; HR = 0.74, 95% CI = 0.54-1.01, p = 0.0592) in models with MMSE and B-QOL. In addition, there were no differences in MMSE and B-QOL scores between arms (p = 0.4752 and p = 0.2767, respectively); higher scores predicted longer survival. MMSE and B-QOL scores held steady in the upper range in both arms for survivors. Younger, fitter patients had better MMSE and B-QOL and longer survival. (c) 2010 Elsevier Inc. All rights reserved.

Cognition and Quality of Life After Chemotherapy Plus Radiotherapy (RT) vs. RT for Pure and Mixed Anaplastic Oligodendrogliomas: Radiation Therapy Oncology Group Trial 9402

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang Meihua, E-mail: mwang@phila.acr.or; Cairncross, Gregory; Shaw, Edward

2010-07-01

Purpose: Radiation Therapy Oncology Group 9402 compared procarbazine, lomustine, and vincristine (PCV) chemotherapy plus radiation therapy (PCV + RT) vs. RT alone for anaplastic oligodendroglioma. Here we report longitudinal changes in cognition and quality of life, effects of patient factors and treatments on cognition, quality of life and survival, and prognostic implications of cognition and quality of life. Methods and Materials: Cognition was assessed by Mini Mental Status Examination (MMSE) and quality of life by Brain-Quality of Life (B-QOL). Scores were analyzed for survivors and within 5 years of death. Shared parameter models evaluated MMSE/B-QOL with survival. Results: For survivors,more » MMSE and B-QOL scores were similar longitudinally and between treatments. For those who died, MMSE scores remained stable initially, whereas B-QOL slowly declined; both declined rapidly in the last year of life and similarly between arms. In the aggregate, scores decreased over time (p = 0.0413 for MMSE; p = 0.0016 for B-QOL) and were superior with age <50 years (p < 0.001 for MMSE; p = 0.0554 for B-QOL) and Karnofsky Performance Score (KPS) 80-100 (p < 0.001). Younger age and higher KPS were associated with longer survival. After adjusting for patient factors and drop-out, survival was longer after PCV + RT (HR = 0.66, 95% CI = 0.49-0.9, p = 0.0084; HR = 0.74, 95% CI = 0.54-1.01, p = 0.0592) in models with MMSE and B-QOL. In addition, there were no differences in MMSE and B-QOL scores between arms (p = 0.4752 and p = 0.2767, respectively); higher scores predicted longer survival. Conclusion: MMSE and B-QOL scores held steady in the upper range in both arms for survivors. Younger, fitter patients had better MMSE and B-QOL and longer survival.« less

Using the Folstein Mini Mental State Exam (MMSE) to explore methodological issues in cognitive aging research.

PubMed

Monroe, Todd; Carter, Michael

2012-09-01

Cognitive scales are used frequently in geriatric research and practice. These instruments are constructed with underlying assumptions that are a part of their validation process. A common measurement scale used in older adults is the Folstein Mini Mental State Exam (MMSE). The MMSE was designed to screen for cognitive impairment and is used often in geriatric research. This paper has three aims. Aim one was to explore four potential threats to validity in the use of the MMSE: (1) administering the exam without meeting the underlying assumptions, (2) not reporting that the underlying assumptions were assessed prior to test administration, (3) use of variable and inconsistent cut-off scores for the determination of presence of cognitive impairment, and (4) failure to adjust the scores based on the demographic characteristics of the tested subject. Aim two was to conduct a literature search to determine if the assumptions of (1) education level assessment, (2) sensory assessment, and (3) language fluency were being met and clearly reported in published research using the MMSE. Aim three was to provide recommendations to minimalize threats to validity in research studies that use cognitive scales, such as the MMSE. We found inconsistencies in published work in reporting whether or not subjects meet the assumptions that underlie a reliable and valid MMSE score. These inconsistencies can pose threats to the reliability of exam results. Fourteen of the 50 studies reviewed reported inclusion of all three of these assumptions. Inconsistencies in reporting the inclusion of the underlying assumptions for a reliable score could mean that subjects were not appropriate to be tested by use of the MMSE or that an appropriate test administration of the MMSE was not clearly reported. Thus, the research literature could have threats to both validity and reliability based on misuse of or improper reported use of the MMSE. Six recommendations are provided to minimalize these threats in future research.

[Performance of an abbreviated mini mental examination to detect dementia in older people].

PubMed

Jiménez, Daniel; Lavados, Manuel; Rojas, Paula; Henríquez, Claudio; Silva, Fernando; Guillón, Marta

2017-07-01

The usefulness of the abbreviated Mini-Mental State Examination included in the Chilean Functional assessment of elderly people (MM-SE-EFAM) to detect Dementia has not been determined. To assess the performance of the MMSE-EFAM to detect dementia. We studied a non-probabilistic sample of subjects older than 65 years who had been assessed by the MMSE-EFAM in a Chilean primary care center during a period of 6 months. Patients underwent clinical evaluation by a neurologist blinded to MMSE-EFAM score, to establish the diagnosis of dementia using DSM-IV-TR criteria. Besides, the full Mini-Mental State Examination (MMSE) was applied. The clinical diagnosis of Dementia was established in 13 of the 54 peoples evaluated. MMSE-EFAM had a sensitivity of 30.8% (95% confidence intervals (CI); 9-61.4) and a specificity of 90.2% (95% CI; 76.9%-97.3%), while MMSE had a sensitivity of 84.6% (95% CI; 54.6-98.1) and a specificity of 58.5% (95% CI; 42.1-73.7). In a receiver operating characteristic (ROC) curve analysis, the areas under the curve (AUC) were 0.77 (95% CI; 0.61-0.93) and 0.82 (95% CI; 0.70-0.95) for MMSE-EFAM and MMSE, respectively. Socio-demographic variables did not influence test performance in both cases. MMSE-EFAM has a low sensitivity to detect patients with Dementia and it is not an effective screening tool. These results are in agreement with the evidence and international guidelines that do not support the use of cognitive screening tools to detect dementia in the older general population.

Clinical efficacy of formula-based bifrontal versus right unilateral electroconvulsive therapy (ECT) in the treatment of major depression among elderly patients: a pragmatic, randomized, assessor-blinded, controlled trial.

PubMed

Bjølseth, Tor Magne; Engedal, Knut; Benth, Jūratė Šaltytė; Dybedal, Gro Strømnes; Gaarden, Torfinn Lødøen; Tanum, Lars

2015-04-01

No prior study has compared the efficacy of bifrontal (BF) vs right unilateral (RUL) electroconvulsive therapy (ECT) by including the subgroup that is most likely to receive it: only elderly patients with major depression (MD). This single-site, randomized, assessor-blinded, controlled trial was conducted from 2009 to 2013. Seventy-three elderly patients with MD, unipolar and bipolar, were treated with a course of formula-based BF ECT or RUL ECT. The 17-item Hamilton Rating Scale for Depression (HRSD17) was used to measure efficacy. Safety was assessed with the Mini Mental State Examination (MMSE). Both electrode placements resulted in highly significant downward trends in symptom severity (all p<0.001), with a non-significant difference between methods (p=0.703). At the end of the ECT course, response rates for the BF and RUL group were 63.9% and 67.6%, respectively. Short-term remission, defined as an HRSD17 score≤7, was achieved in 14 (38.9%) patients in the BF group and 19 (51.4%) patients in the RUL group. Global cognitive function, as measured by the MMSE, did not deteriorate in the two treatment groups. The small number of subjects may have led to reduced power to detect real differences. The MMSE is not sufficient to ascertain the negative effect of ECT on cognition. This study indicates that formula-based BF and RUL ECT are equally efficacious, and that remission rates of formula-based dosing are lower than those previously reported for titrated dosing, in a clinical sample of elderly patients with MD. ClinicalTrials.gov NCT01559324. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Cognitive performance on the mini-mental state examination and the montreal cognitive assessment across the healthy adult lifespan.

PubMed

Gluhm, Shea; Goldstein, Jody; Loc, Kiet; Colt, Alexandra; Liew, Charles Van; Corey-Bloom, Jody

2013-03-01

We sought to compare age-related performance on the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) across the adult lifespan in an asymptomatic, presumably normal, sample. The MMSE is the most commonly used brief cognitive screening test; however, the MoCA may be better at detecting early cognitive dysfunction. We gave the MMSE and MoCA to 254 community-dwelling participants ranging in age from 20 to 89, stratified by decade, and we compared their scores using the Wilcoxon signed rank test. For the total sample, the MMSE and MoCA differed significantly in total scores as well as in visuospatial, language, and memory domains (for all of these scores, P<0.001). Mean MMSE scores declined only modestly across the decades; mean MoCA scores declined more dramatically. There were no consistent domain differences between the MMSE and MoCA during the third and fourth decades; however, significant differences in memory (P<0.05) and language (P<0.001) emerged in the fifth through ninth decades. We conclude that the MoCA may be a better detector of age-related decrements in cognitive performance than the MMSE, as shown in this community-dwelling adult population.

Use of the MC-FAQ and MMSE-FAQ in cognitive screening of older African Americans, Hispanic Americans, and European Americans.

PubMed

Tappen, Ruth M; Rosselli, Monica; Engstrom, Gabriella

2012-11-01

The purpose of this study was to examine the performance of the Mini-Cog-Functional Activities Questionnaire (MC-FAQ) and the Mini-Mental State Examination-Functional Activities Questionnaire (MMSE-FAQ) in cognitive screening of a multiethnic sample of older adults. This is a descriptive psychometric study. Cognitive screening was done in senior centers, at health fairs, and within the nine participating memory disorder centers in the State of Florida. African American, Hispanic American, and European American older adults who participated in this screening were matched on gender, age within 3 years and education within 3 years yielding a sample of 225. The MC-FAQ is a combination of the Mini-Cog and Functional Activities Questionnaire. The MMSE-FAQ combines the MMSE with the FAQ. The Geriatric Depression Scale was used to assess depressive symptoms. African Americans reported significantly less depressive symptoms (F[2, 217] = 10.31, p <0.001) and European Americans had significantly higher mean MMSE scores than the other two groups (F[2, 222] = 3.33, p = 0.037). Participants did not differ by ethnic group on the MC-FAQ or MMSE-FAQ classifications of normal, mild cognitive impairment, or dementia. Age, years of education, and depressive symptoms were significant predictors of MC-FAQ and MMSE-FAQ classifications. The results suggest that these combinations of screening measures may have less culture bias than the MMSE alone. Sensitivity and specificity should be evaluated in these groups with confirmatory neurological and psychiatric diagnosis. 2012 American Association for Geriatric Psychiatry

Cognitive Evolution by MMSE in Poststroke Patients

ERIC Educational Resources Information Center

da Costa, Fabricia Azevedo

2010-01-01

The aim of this study was to investigate the cognitive and clinical evolution of post-acute stroke patients and the evolution of each Mini-Mental State Examination (MMSE) item. A longitudinal study was conducted with 42 poststroke individuals in rehabilitation. The MMSE and the National Institutes of Health Stroke Scale were used to assess…

Coordinated Analysis of Age, Sex, and Education Effects on Change in MMSE Scores

PubMed Central

2013-01-01

Objectives. We describe and compare the expected performance trajectories of older adults on the Mini-Mental Status Examination (MMSE) across six independent studies from four countries in the context of a collaborative network of longitudinal studies of aging. A coordinated analysis approach is used to compare patterns of change conditional on sample composition differences related to age, sex, and education. Such coordination accelerates evaluation of particular hypotheses. In particular, we focus on the effect of educational attainment on cognitive decline. Method. Regular and Tobit mixed models were fit to MMSE scores from each study separately. The effects of age, sex, and education were examined based on more than one centering point. Results. Findings were relatively consistent across studies. On average, MMSE scores were lower for older individuals and declined over time. Education predicted MMSE score, but, with two exceptions, was not associated with decline in MMSE over time. Conclusion. A straightforward association between educational attainment and rate of cognitive decline was not supported. Thoughtful consideration is needed when synthesizing evidence across studies, as methodologies adopted and sample characteristics, such as educational attainment, invariably differ. PMID:23033357

Coordinated analysis of age, sex, and education effects on change in MMSE scores.

PubMed

Piccinin, Andrea M; Muniz-Terrera, Graciela; Clouston, Sean; Reynolds, Chandra A; Thorvaldsson, Valgeir; Deary, Ian J; Deeg, Dorly J H; Johansson, Boo; Mackinnon, Andrew; Spiro, Avron; Starr, John M; Skoog, Ingmar; Hofer, Scott M

2013-05-01

We describe and compare the expected performance trajectories of older adults on the Mini-Mental Status Examination (MMSE) across six independent studies from four countries in the context of a collaborative network of longitudinal studies of aging. A coordinated analysis approach is used to compare patterns of change conditional on sample composition differences related to age, sex, and education. Such coordination accelerates evaluation of particular hypotheses. In particular, we focus on the effect of educational attainment on cognitive decline. Regular and Tobit mixed models were fit to MMSE scores from each study separately. The effects of age, sex, and education were examined based on more than one centering point. Findings were relatively consistent across studies. On average, MMSE scores were lower for older individuals and declined over time. Education predicted MMSE score, but, with two exceptions, was not associated with decline in MMSE over time. A straightforward association between educational attainment and rate of cognitive decline was not supported. Thoughtful consideration is needed when synthesizing evidence across studies, as methodologies adopted and sample characteristics, such as educational attainment, invariably differ.

[Effects of COPD on cognitive functions: a case control study].

PubMed

Sarınç Ulaşlı, Sevinç; Oruç, Serdar; Günay, Ersin; Aktaş, Orçun; Akar, Olcay; Koyuncu, Tülay; Ünlü, Mehmet

2013-01-01

Assessment of disease severity, effects of disease on health status and future events should be considered to direct treatment strategies in chronic obstructive pulmonary disease (COPD) management. Although extrapulmonary effects of COPD are well known, effects of COPD on cognitive functions have not been evaluated sufficiently. therefore we aimed to determine cognitive functions of copd patients in the present study. 112 COPD patients with moderate, severe and very severe irreversible airway obstruction and 44 age matched healthy subjects without COPD and systemic diseases as control group were enrolled to the study. Mini mental state examination (MMSE) was performed to evaluate cognitive functions. MMSE results were compared between patient and control groups. Moreover relationship between exacerbation frequency and cognitive functions was evaluated. Total 156 subjects as 112 COPD patients and 44 healthy subjects were included to the study. Mean age of COPD patients was 65.03 ± 7.63 years, and mean age of control group was 63.63 ± 8.96 years (p= 0.364). Mean score of MMSE in COPD patients was 23.8 ± 4.39, and mean score of MMSE in control group was 26.7 ± 2.88. We determined a significant difference in terms of MMSE scores betweeen patient and control group (p< 0.0001). MMSE scores and FEV1 values were significantly different among patients with moderate, sevre and very severe airflow obstruction (p= 0.001; p< 0.0001 respectively). We found a significant negative correlation between MMSE results and exacerbation frequency during last year (p= 0.003; r= -0.239). Lower MMSE scores of COPD patients than subjects in control group indicates the impairment of cognitive functions in COPD patients. Moreover a negative relationship between MMSE scores with exacerbation frequency during last year suggests that prevention from exacerbation can decrease cognitive impairment in COPD patients. We believe that assessment of cognitive functions and preventive strategies should be considered in COPD management.

Role of physical activity in reducing cognitive decline in older Mexican-American adults.

PubMed

Ottenbacher, Allison J; Snih, Soham Al; Bindawas, Saad M; Markides, Kyriakos S; Graham, James E; Samper-Ternent, Rafael; Raji, Mukaila; Ottenbacher, Kenneth J

2014-09-01

The effect of physical activity on cognitive function in older adults from minority and disadvantaged populations is not well understood. This study examined the longitudinal association between physical activity and cognition in older Mexican Americans. The study methodology included a prospective cohort with longitudinal analysis of data from the Hispanic Established Populations for the Epidemiologic Study of the Elderly. General linear mixed models were used to assess the associations and interactions between physical activity and cognitive function over 14 years. Community-based assessments were performed in participants' homes. Physical activity was recorded for 1,669 older Mexican Americans using the Physical Activity Scale for the Elderly. Cognition was measured using the Mini-Mental State Examination (MMSE) and separated into memory and nonmemory components. A statistically significant positive association was observed between levels of physical activity and cognitive function after adjusting for age, sex, marital status, education, and comorbid health conditions. There was a statistically significant difference in MMSE scores over time between participants in the third (β = 0.11, standard error (SE) = 0.05) and fourth (β = 0.10, SE = 0.2) quartiles of physical activity and those in the first. The protective effect of physical activity on cognitive decline was evident for the memory component of the MMSE but not the nonmemory component after adjusting for covariates. Greater physical activity at baseline was associated with less cognitive decline over 14 years in older Mexican Americans. The reduction in cognitive decline appeared to be related to the memory components of cognitive function. © 2014, Copyright the Authors Journal compilation © 2014, The American Geriatrics Society.

Do subjective memory complaints predict senile Alzheimer dementia?

PubMed

Jungwirth, Susanne; Zehetmayer, Sonja; Weissgram, Silvia; Weber, Germain; Tragl, Karl Heinz; Fischer, Peter

2008-01-01

Many elderly complain about their memory and undergo dementia screening by the Mini-Mental State Examination (MMSE). While objective memory impairment always precedes Alzheimer dementia (AD) it is unclear whether subjective memory complaints are predicting AD. We tried to answer this question in a prospective cohort study. The 75-years old non-demented inhabitants of Vienna-Transdanube were investigated for conversion to AD after 30 months. The predictive value of subjective memory complaints was analysed in two groups: subjects with high MMSE-score (28-30) and subjects with low MMSE-score (23-27). Only in subjects with high MMSE univariate analyses showed an association between subjective memory complaints and incident AD. In both groups the verbal memory test was the main predictor of AD in multivariate analyses. We suggest to perform memory testing in subjects complaining about memory irrespective of their performance in a screening procedure like the MMSE.

[Using the MMSE as a cognitive screener among Turkish and Moroccan migrants].

PubMed

Zwart, L A R; Goudsmit, M; van Campen, J P C M; Rijkers, C J M; Wind, A W

2015-02-01

The Dutch population of first generation Turkish and Moroccan migrants is ageing. Among them hypertension and diabetes mellitus are frequent findings, which will probably cause an increased incidence of dementia. The language barrier, low education and cultural differences make the diagnosis more difficult. To what extent the MMSE can be used as a cognitive screener in this population will be investigated in this retrospective study.Patients received standard diagnostics, a professional translator addressed the language barrier. Correspondence was scored on characteristics of dementia, a procedure was used to diagnose without including the MMSE score. The optimal cut-off was calculated with the Youden Index and Area under the ROC (AUROC).106 patients were included, 61% had no education. Average MMSE-score was 16, with dementia 12, without 19. The AUROC was 0.85, optimal cut-off was 18 with a Youden index of 0.61.By using a professional translator the MMSE can possibly be used as a cognitive screener in this population. However, the cognitive skills addressed by the MMSE require an education and language skills. Developing a test that is independent of education and language barrier will probably be better.

Relationship between the Montreal Cognitive Assessment and Mini-mental State Examination for assessment of mild cognitive impairment in older adults.

PubMed

Trzepacz, Paula T; Hochstetler, Helen; Wang, Shufang; Walker, Brett; Saykin, Andrew J

2015-09-07

The Montreal Cognitive Assessment (MoCA) was developed to enable earlier detection of mild cognitive impairment (MCI) relative to familiar multi-domain tests like the Mini-Mental State Exam (MMSE). Clinicians need to better understand the relationship between MoCA and MMSE scores. For this cross-sectional study, we analyzed 219 healthy control (HC), 299 MCI, and 100 Alzheimer's disease (AD) dementia cases from the Alzheimer's Disease Neuroimaging Initiative (ADNI)-GO/2 database to evaluate MMSE and MoCA score distributions and select MoCA values to capture early and late MCI cases. Stepwise variable selection in logistic regression evaluated relative value of four test domains for separating MCI from HC. Functional Activities Questionnaire (FAQ) was evaluated as a strategy to separate dementia from MCI. Equi-percentile equating produced a translation grid for MoCA against MMSE scores. Receiver Operating Characteristic (ROC) analyses evaluated lower cutoff scores for capturing the most MCI cases. Most dementia cases scored abnormally, while MCI and HC score distributions overlapped on each test. Most MCI cases scored ≥ 17 on MoCA (96.3%) and ≥ 24 on MMSE (98.3%). The ceiling effect (28-30 points) for MCI and HC was less using MoCA (18.1%) versus MMSE (71.4%). MoCA and MMSE scores correlated most for dementia (r = 0.86; versus MCI r = 0.60; HC r = 0.43). Equi-percentile equating showed a MoCA score of 18 was equivalent to MMSE of 24. ROC analysis found MoCA ≥ 17 as the cutoff between MCI and dementia that emphasized high sensitivity (92.3%) to capture MCI cases. The core and orientation domains in both tests best distinguished HC from MCI groups, whereas comprehension/executive function and attention/calculation were not helpful. Mean FAQ scores were significantly higher and a greater proportion had abnormal FAQ scores in dementia than MCI and HC. MoCA and MMSE were more similar for dementia cases, but MoCA distributes MCI cases across a broader score range with less ceiling effect. A cutoff of ≥ 17 on the MoCA may help capture early and late MCI cases; depending on the level of sensitivity desired, ≥ 18 or 19 could be used. Functional assessment can help exclude dementia cases. MoCA scores are translatable to the MMSE to facilitate comparison.

Using the Oxford Cognitive Screen to Detect Cognitive Impairment in Stroke Patients: A Comparison with the Mini-Mental State Examination.

PubMed

Mancuso, Mauro; Demeyere, Nele; Abbruzzese, Laura; Damora, Alessio; Varalta, Valentina; Pirrotta, Fabio; Antonucci, Gabriella; Matano, Alessandro; Caputo, Marina; Caruso, Maria Giovanna; Pontiggia, Giovanna Teresa; Coccia, Michela; Ciancarelli, Irene; Zoccolotti, Pierluigi

2018-01-01

The Oxford Cognitive Screen (OCS) was recently developed with the aim of describing the cognitive deficits after stroke. The scale consists of 10 tasks encompassing five cognitive domains: attention and executive function, language, memory, number processing, and praxis. OCS was devised to be inclusive and un-confounded by aphasia and neglect. As such, it may have a greater potential to be informative on stroke cognitive deficits of widely used instruments, such as the Mini-Mental State Examination (MMSE) or the Montreal Cognitive Assessment, which were originally devised for demented patients. The present study compared the OCS with the MMSE with regards to their ability to detect cognitive impairments post-stroke. We further aimed to examine performance on the OCS as a function of subtypes of cerebral infarction and clinical severity. 325 first stroke patients were consecutively enrolled in the study over a 9-month period. The OCS and MMSE, as well as the Bamford classification and NIHSS, were given according to standard procedures. About a third of patients (35.3%) had a performance lower than the cutoff (<22) on the MMSE, whereas 91.6% were impaired in at least one OCS domain, indicating higher incidences of impairment for the OCS. More than 80% of patients showed an impairment in two or more cognitive domains of the OCS. Using the MMSE as a standard of clinical practice, the comparative sensitivity of OCS was 100%. Out of the 208 patients with normal MMSE performance 180 showed impaired performance in at least one domain of the OCS. The discrepancy between OCS and MMSE was particularly strong for patients with milder strokes. As for subtypes of cerebral infarction, fewer patients demonstrated widespread impairments in the OCS in the Posterior Circulation Infarcts category than in the other categories. Overall, the results showed a much higher incidence of cognitive impairment with the OCS than with the MMSE and demonstrated no false negatives for OCS vs MMSE. It is concluded that OCS is a sensitive screen tool for cognitive deficits after stroke. In particular, the OCS detects high incidences of stroke-specific cognitive impairments, not detected by the MMSE, demonstrating the importance of cognitive profiling.

Efficacy and safety of haloperidol versus atypical antipsychotic medications in the treatment of delirium.

PubMed

Yoon, Hyung-Jun; Park, Kyoung-Min; Choi, Won-Jung; Choi, Soo-Hee; Park, Jin-Young; Kim, Jae-Jin; Seok, Jeong-Ho

2013-09-30

Most previous studies on the efficacy of antipsychotic medication for the treatment of delirium have reported that there is no significant difference between typical and atypical antipsychotic medications. It is known, however, that older age might be a predictor of poor response to antipsychotics in the treatment of delirium. The objective of this study was to compare the efficacy and safety of haloperidol versus three atypical antipsychotic medications (risperidone, olanzapine, and quetiapine) for the treatment of delirium with consideration of patient age. This study was a 6-day, prospective, comparative clinical observational study of haloperidol versus atypical antipsychotic medications (risperidone, olanzapine, and quetiapine) in patients with delirium at a tertiary level hospital. The subjects were referred to the consultation-liaison psychiatric service for management of delirium and were screened before enrollment in this study. A total of 80 subjects were assigned to receive either haloperidol (N = 23), risperidone (N = 21), olanzapine (N = 18), or quetiapine (N = 18). The efficacy was evaluated using the Korean version of the Delirium Rating Scale-Revised-98 (DRS-K) and the Korean version of the Mini Mental Status Examination (K-MMSE). The safety was evaluated by the Udvalg Kliniske Undersogelser side effect rating scale. There were no significant differences in mean DRS-K severity or K-MMSE scores among the four groups at baseline. In all groups, the DRS-K severity score decreased and the K-MMSE score increased significantly over the study period. However, there were no significant differences in the improvement of DRS-K or K-MMSE scores among the four groups. Similarly, cognitive and non-cognitive subscale DRS-K scores decreased regardless of the treatment group. The treatment response rate was lower in patients over 75 years old than in patients under 75 years old. Particularly, the response rate to olanzapine was poorer in the older age group. Fifteen subjects experienced a few adverse events, but there were no significant differences in adverse event profiles among the four groups. Haloperidol, risperidone, olanzapine, and quetiapine were equally efficacious and safe in the treatment of delirium. However, age is a factor that needs to be considered when making a choice of antipsychotic medication for the treatment of delirium. Clinical Research Information Service, Republic of Korea, (http://cris.nih.go.kr/cris/en/search/basic_search.jsp, Registered Trial No. KCT0000632).

People with Parkinson Disease and Normal MMSE Score Have a Broad Range of Cognitive Performance

PubMed Central

Burdick, DJ; Cholerton, B; Watson, GS; Siderowf, A; Trojanowski, JQ; Weintraub, D; Ritz, B; Rhodes, SL; Rausch, R; Factor, SA; Wood-Siverio, C; Quinn, JF; Chung, KA; Srivatsal, S; Edwards, KL; Montine, TJ; Zabetian, CP; Leverenz, JB

2014-01-01

Background Cognitive impairment, including dementia, is common in Parkinson disease (PD). The Mini-Mental State Examination (MMSE) has been recommended as a screening tool for PDD, with values below 26 indicative of possible dementia. Using a detailed neuropsychological battery, we examined the range of cognitive impairment in PD patients with a MMSE score ≥ 26. Methods In this multi-center, cross-sectional, observational study, we performed neuropsychological testing in a sample of 788 PD patients with MMSE ≥ 26. Evaluation included tests of global cognition, executive function, language, memory, and visuospatial skills. A consensus panel reviewed results for 342 subjects and assigned a diagnosis of no cognitive impairment, mild cognitive impairment, or dementia. Results 67% of the 788 subjects performed 1.5 standard deviations below the normative mean on at least one test. On eight of the 15 tests, more than 20% of subjects scored 1.5 standard deviations or more below the normative mean. Greatest impairments were found on Hopkins Verbal Learning and Digit Symbol Coding tests. The sensitivity of the MMSE to detect dementia was 45% in a subset of participants who underwent clinical diagnostic procedures. Conclusions A remarkably wide range of cognitive impairment can be found in PD patients with a relatively high score on the MMSE, including a level of cognitive impairment consistent with dementia. Given these findings, clinicians must be aware of the limitations of the MMSE in detecting cognitive impairment, including dementia, in PD. PMID:25073717

Predictors of Cognitive and Functional Decline in Patients With Alzheimer Disease Dementia From Brazil.

PubMed

Oliveira, Fabricio F; Chen, Elizabeth S; Smith, Marilia C; Bertolucci, Paulo H F

2016-01-01

Little is known on how risk factors for Alzheimer disease (AD) dementia affect disease progression, much less for populations with low mean schooling, whereas the transcription of APOE may be regulated by nongenetic factors. In this 44-month cohort study, 214 consecutive outpatients with late-onset AD were assessed for rates of cognitive and functional decline by way of Clinical Dementia Rating and Mini-Mental State Examination (MMSE) scores, keeping blinded assessment of APOE haplotypes. Subjects were evaluated for sex, schooling, age of dementia onset, and cerebrovascular risk factors (including Framingham risk scores). Of the 214 patients, there were 146 (68.2%) women and 113 (52.8%) APOE4+ carriers. The mean age of AD onset was 73.4±6.5 years-old, negatively correlated with time to Clinical Dementia Rating >1.0 (β=-0.132; ρ<0.001), MMSE=20 (β=-0.105; ρ<0.001), and MMSE=15 (β=-0.124; ρ=0.003), more significantly for women and APOE4+ carriers. Mean schooling was 4.18±3.7 years, correlated with time to MMSE=20 and MMSE=15 for women and APOE4+ carriers. Body mass index was correlated with time to MMSE=20 only for men (ρ=0.006). The 10-year coronary heart disease risk was correlated with time to MMSE=20 only for APOE4+ carriers (ρ=0.015). These outcomes suggest interactions among genomic effects of cognitive reserve, cerebral perfusion, and hormonal changes over mechanisms of neurodegeneration.

Physical activity and cognition in the northern Manhattan study.

PubMed

Willey, Joshua Z; Park Moon, Yeseon; Ruder, Rachel; Cheung, Yuen K; Sacco, Ralph L; Elkind, Mitchell S V; Wright, Clinton B

2014-01-01

To test the hypothesis that leisure time physical activity (PA) is associated with cognitive status. We assessed cognition using the Mini-Mental Status Examination (MMSE) at enrollment and using the modified Telephone Interview for Cognitive Status (TICS-m) administered annually since 2001 in the Northern Manhattan Study. Baseline measures of leisure time PA were collected via in-person questionnaires. Total PA was categorized into 3 groups based on the metabolic equivalent (MET) score, a composite of total reported intensity and time. We used linear regression models to examine the association of PA with MMSE, and generalized estimating equations for change in TICS-m over time. There were 3,298 stroke-free participants with MMSE data (mean MMSE 26.0 ± 3.8) and 2,279 with TICS-m scores available. Compared to no PA, those with the upper quartile of MET scores had greater baseline MMSE scores (adjusted β = 0.4, p = 0.01) but no association with change in TICS-m over time. There were interactions (p < 0.05) between PA and both insurance and education; compared to no PA, those in the upper quartile of MET scores had a greater MMSE score only among those with Medicaid/no insurance (adjusted β = 0.83, p = 0.0005) and those who did not complete high school (adjusted β = 0.68, p = 0.001). Increased levels of PA were associated with better baseline MMSE, particularly among those with socioeconomic disadvantages, but not with cognitive decline. © 2013 S. Karger AG, Basel.

Influence of anxiety symptoms on improvement of neurocognitive functions in patients with major depressive disorder: A 12-week, multicenter, randomized trial of tianeptine versus escitalopram, the CAMPION study.

PubMed

Yoo, Ikki; Woo, Jong-Min; Lee, Seung-Hwan; Fava, Maurizio; Mischoulon, David; Papakostas, George I; Kim, Eui-Joong; Chung, Seockhoon; Ha, Jee Hyun; Jeon, Hong Jin

2015-10-01

Previous research has reported evidence that patients with major depressive disorder (MDD) show anxiety symptoms and neurocognitive impairments. However, the influence of anxiety on neurocognitive function in MDD patients during antidepressant treatment is unclear. MDD patients (n=164) completed a 12-week, multicenter, randomized trial assigned in a 1:1 ratio to either tianeptine or escitalopram. Changes of anxiety symptoms were assessed by the Hamilton Anxiety Rating Scale (HAM-A), and the Hamilton Depression Rating Scale (HAM-D), self-rated subjective cognitive impairment on memory and concentration, the Mini-Mental Status Examination (MMSE), Continuous Performance Test (CPT), Verbal Learning Test (VLT), and Raven's Progressive Matrices (RPM) were assessed every 4 weeks. During 12 weeks of treatment, decrease in the HAM-A score was significantly associated with improvement of subjective cognitive impairments on memory (p<0.001) and concentration (p<0.001), and objective measures on delayed memory (p=0.006) and reasoning ability (p=0.002), after adjusting for covariates such as baseline HAM-A scores, time, sex, age, education years and assigned medication using the Mixed effects and Generalized Estimated Equation model analysis. However, the other cognitive outcome variables, immediate memory, commission error, and MMSE, which showed significant improvement through 12-week study period, showed no significant association with improvement of anxiety. Improvement of anxiety symptoms was significantly associated with improvement in subjective and objective neurocognitive functions such as delayed memory and reasoning ability in elderly MDD patients during antidepressant treatment, but not significantly associated with improvement of immediate memory and commission error. ClinicalTrials.gov identifier NCT01309776. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparison between mini mental state examination (MMSE) and Montreal cognitive assessment Indonesian version (MoCA-Ina) as an early detection of cognitive impairments in post-stroke patients

NASA Astrophysics Data System (ADS)

Lestari, S.; Mistivani, I.; Rumende, C. M.; Kusumaningsih, W.

2017-08-01

Mild cognitive impairment (MCI) is defined as cognitive impairment that may never develop into dementia. Cognitive impairment is one long-term complication of a stroke. The Mini Mental State Examination (MMSE), which is commonly used as a screening tool for cognitive impairment, has a low sensitivity to detect cognitive impairment, especially MCI. Alternatively, the Montreal Cognitive Assessment Indonesian version (MoCA-Ina) has been reported to have a higher sensitivity than the MMSE. The aim of this study was to compare the proportion of MCI identified between the MMSE and MoCA-Ina in stroke patients. This was a cross-sectional study of stroke outpatients who attended the Polyclinic Neuromuscular Division, Rehabilitation Department, and Polyclinic Stroke, Neurology Department Cipto Mangunkusumo General Hospital, Jakarta. The proportion of MCI identified using the MMSE was 31.03% compared to 72.41% when using the MoCA-Ina. This difference was statistically significant (Fisher’s exact test, p = 0.033). The proportion of MCI in stroke patients was higher when using the MoCA-Ina compared to the MMSE. The MoCA-Ina should be used as an alternative in the early detection of MCI in stroke patients, especially those undergoing rehabilitation.

Item and scale differential functioning of the Mini-Mental State Exam assessed using the Differential Item and Test Functioning (DFIT) Framework.

PubMed

Morales, Leo S; Flowers, Claudia; Gutierrez, Peter; Kleinman, Marjorie; Teresi, Jeanne A

2006-11-01

To illustrate the application of the Differential Item and Test Functioning (DFIT) method using English and Spanish versions of the Mini-Mental State Examination (MMSE). Study participants were 65 years of age or older and lived in North Manhattan, New York. Of the 1578 study participants who were administered the MMSE 665 completed it in Spanish. : The MMSE contains 20 items that measure the degree of cognitive impairment in the areas of orientation, attention and calculation, registration, recall and language, as well as the ability to follow verbal and written commands. After assessing the dimensionality of the MMSE scale, item response theory person and item parameters were estimated separately for the English and Spanish sample using Samejima's 2-parameter graded response model. Then the DFIT framework was used to assess differential item functioning (DIF) and differential test functioning (DTF). Nine items were found to show DIF; these were items that ask the respondent to name the correct season, day of the month, city, state, and 2 nearby streets, recall 3 objects, repeat the phrase no ifs, no ands, no buts, follow the command, "close your eyes," and the command, "take the paper in your right hand, fold the paper in half with both hands, and put the paper down in your lap." At the scale level, however, the MMSE did not show differential functioning. Respondents to the English and Spanish versions of the MMSE are comparable on the basis of scale scores. However, assessments based on individual MMSE items may be misleading.

Neuropsychometric tests in cross sectional and longitudinal studies - a regression analysis of ADAS - cog, SKT and MMSE.

PubMed

Ihl, R; Grass-Kapanke, B; Jänner, M; Weyer, G

1999-11-01

In clinical and drug studies, different neuropsychometric tests are used. So far, no empirical data have been published to compare studies using different tests. The purpose of this study was to calculate a regression formula allowing a comparison of cross-sectional and longitudinal data from three neuropsychometric tests that are frequently used in drug studies (Alzheimer's Disease Assessment Scale, ADAS-cog; Syndrom Kurz Test, SKT; Mini Mental State Examination, MMSE). 177 patients with dementia according to ICD10 criteria were studied for the cross sectional and 61 for the longitudinal analysis. Correlations and linear regressions were calculated between tests. Significance was proven with ANOVA and t-tests using the SPSS statistical package. Significant Spearman correlations and slopes in the regression occurred in the cross sectional analysis (ADAS-cog-SKT r(s) = 0.77, slope = 0.45, SKT-ADAS-cog slope = 1.3, r2 = 0.59; ADAS-cog-MMSE r2 = 0.76, slope = -0.42, MMSE-ADAS-cog slope = -1.5, r2 = 0.64; MMSE-SKT r(s) = -0.79, slope = -0.87, SKT-MMSE slope = -0.71, r2 = 0.62; p<0.001 after Bonferroni correction; N = 177) and in the longitudinal analysis (SKT-ADAS-cog, r(s) = 0.48, slope = 0.69, ADAS-cog-SKT slope = 0.69, p<0.001, r2 = 0.32, MMSE-SKT, r(s) = 0.44, slope = -0.41, SKT-MMSE, slope = -0.55, p<0.001, r2 = 0.21). The results allow calculation of ADAS-scores when SKT scores are given, and vice versa. In longitudinal studies or in the course of the disease, scores assessed with the ADAS-cog and the SKT may now be statistically compared. In all comparisons, bottom and ceiling effects of the tests have to be taken into account.

Age, education, and changes in the Mini-Mental State Exam scores of older women: findings from the Nun Study.

PubMed

Butler, S M; Ashford, J W; Snowdon, D A

1996-06-01

To describe the relationship of Mini-Mental State Exam (MMSE) scores and changes over time in MMSE scores to age and education in a population of older women. A prospective study of a defined population. Various motherhouses and church-run health care facilities in the Eastern, Midwestern, and Southern regions of the United States. Catholic sisters (nuns) participating in the Nun Study, a study of aging and Alzheimer's Disease. The 678 participants were 75 to 102 years old (mean 83.3, standard deviation 5.5, median 82.3) at the time of the first functional assessment. Second assessments were obtained an average of 1.6 years later on 575 survivors. The outcome variables were MMSE scores at the first assessment (Time-one), and MMSE scores at the second assessment (Time-two). The independent variables were age at Time-one, and education (bachelor's degree or no bachelor's degree). Time-one MMSE scores decreased with age at Time-one. The decrease in MMSE scores with age was less in sisters with bachelor's degrees than in sisters without bachelor's degrees. The changes in MMSE scores had a "U-shaped" relationship with Time-one score, where the greatest declines occurred in sisters with intermediate Time-one scores. Stratified analysis by age, education, and Time-one MMSE scores of 20 or greater because of the small numbers of sisters with Time-one scores less than 20. In sisters with Time-one MMSE scores in the categories 20 to 23, 24 to 26, or 27 to 30, older ages at Time-one were associated with greater decline in those with bachelor's degrees, but not in those without bachelor's degrees. Also, lower education was associated with greater decline in sisters aged 75 to 84 years at Time-one, but this education effect disappeared or reversed in sisters who were 85 years of age or older at Time-one. Cognitive function as measured by the MMSE decreased with age at Time-one, most steeply as a function of age in those without bachelor's degrees. Cognitive function declined over 1.6 years within individuals, and the extent of decline increased with age in the sisters with bachelor's degrees. The extent of decline varied with age and education in an interactive manner, which may have been attributable to a hardy survivor effect in lower educated sisters. It may be necessary to consider such interactions whenever changes in function are studied, particularly when analyses are stratified by the initial level of function.

A hybrid demodulation method of fiber-optic Fabry-Perot pressure sensor

NASA Astrophysics Data System (ADS)

Yu, Le; Lang, Jianjun; Pan, Yong; Wu, Di; Zhang, Min

2013-12-01

The fiber-optic Fabry-Perot pressure sensors have been widely applied to measure pressure in oilfield. For multi-well it will take a long time (dozens of seconds) to demodulate downhole pressure values of all wells by using only one demodulation system and it will cost a lot when every well is equipped with one system, which heavily limits the sensor applied in oilfield. In present paper, a new hybrid demodulation method, combining the windowed nonequispaced discrete Fourier Transform (nDFT) method with segment search minimum mean square error estimation (MMSE) method, was developed, by which the demodulation time can be reduced to 200ms, i.e., measuring 10 channels/wells was less than 2s. Besides, experimental results showed the demodulation cavity length of the fiber-optic Fabry-Perot sensor has a maximum error of 0.5 nm and consequently pressure measurement accuracy can reach 0.4% F.S.

A retrospective analysis of the sentence writing component of the Mini Mental State Examination: cognitive and affective aspects.

PubMed

Press, Yan; Velikiy, Natalia; Berzak, Alex; Tandeter, Howard; Peleg, Roni; Freud, Tamar; Punchik, Boris; Dwolatzky, Tzvi

2012-01-01

One of the components of the Mini Mental State Examination (MMSE) is the request to write a sentence. We investigated the relationship between the characteristics of the written sentence of the MMSE and the cognitive and affective status of elderly patients. The characteristics of the sentence were compared to the total MMSE score, sociodemographic characteristics, tests evaluating cognition and affective status, and diagnoses. The number of words was significantly associated with the degree of cognitive impairment, whereas the emotional polarity of sentences and concerns about health were associated with depression. Characteristics of the MMSE sentence may provide important additional information regarding both cognition and affect when assessing older people. Copyright © 2012 S. Karger AG, Basel.

Associations of cumulative Pb exposure and longitudinal changes in Mini-Mental Status Exam scores, global cognition and domains of cognition: The VA Normative Aging Study.

PubMed

Farooqui, Zishaan; Bakulski, Kelly M; Power, Melinda C; Weisskopf, Marc G; Sparrow, David; Spiro, Avron; Vokonas, Pantel S; Nie, Linda H; Hu, Howard; Park, Sung Kyun

2017-01-01

Lead (Pb) exposure has been associated with poorer cognitive function cross-sectionally in aging adults, however the association between cumulative Pb exposure and longitudinal changes in cognition is little characterized. In a 1993-2007 subcohort of the VA Normative Aging Study (Mini-mental status exam (MMSE) n=741; global cognition summary score n=715), we used linear mixed effects models to test associations between cumulative Pb exposure (patella or tibia bone Pb) and repeated measures of cognition (MMSE, individual cognitive tests, and global cognition summary). Cox proportional hazard modeling assessed the risk of an MMSE score falling below 25. Among men 51-98 at baseline, higher patella Pb concentration (IQR: 21μg/g) was associated with -0.13 lower baseline MMSE (95% CI: -0.25, -0.004) and faster longitudinal MMSE decline (-0.016 units/year, 95% CI: -0.032, -0.0004) over 15 years. Each IQR increase in patella Pb was associated with increased risk of a MMSE score below 25 (HR=1.21, 95% CI: 0.99, 1.49; p=0.07). There were no significant associations between Pb and global cognition (both baseline and longitudinal change). Patella Pb was associated with faster longitudinal decline in Word List Total Recall in the language domain (0.014 units/year, 95% CI: -0.026, -0.001) and Word List Delayed Recall in the memory domain (0.014 units/year, 95% CI: -0.027, -0.002). We found weaker associations with tibia Pb. Cumulative Pb exposure is associated with faster declines in MMSE and Word List Total and Delayed Recall tests. These findings support the hypothesis that Pb exposure accelerates cognitive aging. Copyright © 2016 Elsevier Inc. All rights reserved.

Cognitive impairment and mortality among the oldest-old Chinese.

PubMed

An, Ruopeng; Liu, Gordon G

2016-12-01

This study examined the relationship between cognitive impairment status and all-cause mortality among the oldest-old Chinese. A total of 7474 survey participants 80 years of age and above came from the Chinese Longitudinal Healthy Longevity Survey 1998-2012 waves. Baseline cognitive impairment status was assessed using the Chinese version of the mini-mental state examination (MMSE), with total score ranging from 0 to 30. Cox proportional hazards regressions were performed to examine the relationship between baseline cognitive impairment status in 1998 and subsequent all-cause mortality during 1998-2012, adjusting for various individual characteristics at baseline. Compared with those with no or mild cognitive impairment (18 ≤ MMSE score ≤ 30) at baseline, participants with moderate-to-severe cognitive impairment (0 ≤ MMSE score ≤ 17) were 28% (95% confidence interval = 20%, 37%) more likely to die during the follow-up period from 1998 to 2012. A dose-response relationship between baseline severity level of cognitive impairment and mortality was evident. Compared with those without cognitive impairment (25 ≤ MMSE score ≤ 30) at baseline, those having mild cognitive impairment (18 ≤ MMSE score ≤ 24), moderate cognitive impairment (10 ≤ MMSE score ≤ 17), and severe cognitive impairment (0 ≤ MMSE score ≤ 9), were 20% (13%, 28%), 38% (27%, 51%), and 47% (33%, 62%) more likely to die during the follow-up period. No statistically significant gender differences in the relationship between cognitive impairment status and mortality were found. Baseline cognitive impairment was inversely associated with longevity among the oldest-old Chinese. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Total homocysteine and cognition in a tri-ethnic cohort

PubMed Central

Wright, C.B.; Lee, H.-S.; Paik, M.C.; Stabler, S.P.; Allen, R.H.; Sacco, R.L.

2005-01-01

Objective: Several studies implicate elevated homocysteine as a risk factor for dementia and cognitive decline, but most studies have involved subjects older than 55 years from homogeneous populations. The authors examined homocysteine and cognition in a tri-ethnic community sample 40 years and older. Method: The Northern Manhattan Study includes 3,298 stroke-free subjects. Of these 2,871 had baseline fasting total homocysteine (tHcy) levels and Mini-Mental State Examination (MMSE) scores available. The authors used multiple linear regression to examine the cross-sectional association between baseline tHcy levels and mean MMSE scores adjusting for sociodemographic and vascular risk factors. Results: Homocysteine levels were related to age, renal function, and B12 deficiency. Those with B12 deficiency had tHcy levels five points higher (9.4 vs 14.4 nmol/L). Mean MMSE scores differed by age, sex, and race-ethnic group. Those with hypertension, diabetes, cardiac disease, and B12 deficiency had lower MMSE scores. In multivariate analyses, elevated tHcy was associated with lower mean MMSE scores for those older than 65 but not for those 40 to 64. Adjusting for B12 deficiency and sociodemographic factors the mean MMSE was 2.2 points lower for each unit increase in the log tHcy level (95% CI −3.6, −0.9). Adding vascular risk factors to the model did not attenuate this effect (mean MMSE −2.2 points; 95% CI −3.5, −0.9). Conclusions: Elevated homocysteine was independently associated with decreased cognition in subjects older than 65 in this tri-ethnic cohort, adjusting for sociodemographic and vascular risk factors. PMID:15277617

Methylation and demethylation of intermediates selenide and methylselenol in the metabolism of selenium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ohta, Yuki; Suzuki, Kazuo T.

2008-01-15

All nutritional selenium sources are transformed into the assumed common intermediate selenide for the syntheses of selenoproteins for utilization and/or of selenosugar for excretion. Methylselenol [monomethylselenide, MMSe] is the assumed intermediate leading to other methylated metabolites, dimethylselenide (DMSe) and trimethylselenonium (TMSe) for excretion, and also to the intermediate selenide from methylselenocysteine and methylseleninic acid (MSA). Here, related methylation and demethylation reactions were studied in vitro by providing chemically reactive starting substrates ({sup 76}Se-selenide, {sup 77}Se-MMSe and {sup 82}Se-DMSe) which were prepared in situ by the reduction of the corresponding labeled proximate precursors ({sup 76}Se-selenite, {sup 77}Se-MSA and {sup 82}Se-dimethylselenoxide (DMSeO),more » respectively) with glutathione, the three substrates being incubated simultaneously in rat organ supernatants and homogenates. The resulting chemically labile reaction products were detected simultaneously by speciation analysis with HPLC-ICP-MS after converting the products and un-reacted substrates to the corresponding oxidized derivatives (selenite, MSA and DMSeO). The time-related changes in selenium isotope profiles showed that demethylation of MMSe to selenide was efficient but that of DMSe to MMSe was negligible, whereas methylation of selenide to MMSe, and MMSe to DMSe were efficient, and that of DMSe to TMSe occurred less efficiently. The present methylation and demethylation reactions on equilibrium between selenide, MMSe and DMSe without producing selenosugar and selenoproteins indicated that DMSe rather than TMSe is produced as the end product, suggesting that DMSe is to be excreted more abundantly than TMSe. Organ-dependent differences in the methylation and demethylation reactions were characterized for the liver, kidney and lung.« less

Cross-validation of a Shortened Battery for the Assessment of Dysexecutive Disorders in Alzheimer Disease.

PubMed

Godefroy, Olivier; Martinaud, Olivier; Verny, Marc; Mosca, Chrystèle; Lenoir, Hermine; Bretault, Eric; Devendeville, Agnès; Diouf, Momar; Pere, Jean-Jacques; Bakchine, Serge; Delabrousse-Mayoux, Jean-Philippe; Roussel, Martine

2016-01-01

The frequency of executive disorders in mild-to-moderate Alzheimer disease (AD) has been demonstrated by the application of a comprehensive battery. The present study analyzed data from 2 recent multicenter studies based on the same executive battery. The objective was to derive a shortened battery by using the GREFEX population as a training dataset and by cross-validating the results in the REFLEX population. A total of 102 AD patients of the GREFEX study (MMSE=23.2±2.9) and 72 patients of the REFLEX study (MMSE=20.8±3.5) were included. Tests were selected and receiver operating characteristic curves were generated relative to the performance of 780 controls from the GREFEX study. Stepwise logistic regression identified 3 cognitive tests (Six Elements Task, categorical fluency and Trail Making Test B error) and behavioral disorders globally referred as global hypoactivity (P=0.0001, all). This shortened battery was as accurate as the entire GREFEX battery in diagnosing dysexecutive disorders in both training group and the validation group. Bootstrap procedure confirmed the stability of AUC. A shortened battery based on 3 cognitive tests and 3 behavioral domains provides a high diagnosis accuracy of executive disorders in mild-to-moderate AD.

Estimators of The Magnitude-Squared Spectrum and Methods for Incorporating SNR Uncertainty

PubMed Central

Lu, Yang; Loizou, Philipos C.

2011-01-01

Statistical estimators of the magnitude-squared spectrum are derived based on the assumption that the magnitude-squared spectrum of the noisy speech signal can be computed as the sum of the (clean) signal and noise magnitude-squared spectra. Maximum a posterior (MAP) and minimum mean square error (MMSE) estimators are derived based on a Gaussian statistical model. The gain function of the MAP estimator was found to be identical to the gain function used in the ideal binary mask (IdBM) that is widely used in computational auditory scene analysis (CASA). As such, it was binary and assumed the value of 1 if the local SNR exceeded 0 dB, and assumed the value of 0 otherwise. By modeling the local instantaneous SNR as an F-distributed random variable, soft masking methods were derived incorporating SNR uncertainty. The soft masking method, in particular, which weighted the noisy magnitude-squared spectrum by the a priori probability that the local SNR exceeds 0 dB was shown to be identical to the Wiener gain function. Results indicated that the proposed estimators yielded significantly better speech quality than the conventional MMSE spectral power estimators, in terms of yielding lower residual noise and lower speech distortion. PMID:21886543

Increased Risk for Falling Associated with Subtle Cognitive Impairment: Secondary Analysis of a Randomized Clinical Trial

PubMed Central

Gleason, Carey E.; Gangnon, Ronald E.; Fischer, Barbara L.; Mahoney, Jane E.

2009-01-01

Background/Aims Having dementia increases patients’ risk for accidental falls. However, it is unknown if having mild cognitive deficits also elevates a person's risk for falls. This study sought to clarify the relationship between subtle cognitive impairment, measured with a widely-used, clinic-based assessment, the Mini Mental State Exam (MMSE), and risk for falls. Methods In a secondary analysis of the Kenosha County Falls Prevention Study, a randomized controlled trial targeting older adults at risk for falls, we examined the association between baseline MMSE and prospective rate of falls over 12 months in 172 subjects randomized to control group. Results Using univariate analysis, the rate of falls increased with each unit decrease in MMSE score down to at least 22 (rate ratio 1.25, 95% confidence interval (CI) 1.09–1.45, p = 0.0026). Using stepwise multivariate regression, controlling for ability to perform activities of daily living, use of assistive device, current exercise, and arthritis, the association between MMSE score and falls rate persisted (rate ratio 1.20, 95% CI 1.03–1.40, p = 0.021). Conclusion Minimal decrements on the MMSE were associated with elevations in rate of falls, suggesting that subtle cognitive deficits reflected in MMSE scores above a cut-off consistent with a diagnosis of dementia, can influence risk for falls. PMID:19602883

Transitions across cognitive states and death among older adults in relation to education: A multistate survival model using data from six longitudinal studies.

PubMed

Robitaille, Annie; van den Hout, Ardo; Machado, Robson J M; Bennett, David A; Čukić, Iva; Deary, Ian J; Hofer, Scott M; Hoogendijk, Emiel O; Huisman, Martijn; Johansson, Boo; Koval, Andriy V; van der Noordt, Maaike; Piccinin, Andrea M; Rijnhart, Judith J M; Singh-Manoux, Archana; Skoog, Johan; Skoog, Ingmar; Starr, John; Vermunt, Lisa; Clouston, Sean; Muniz Terrera, Graciela

2018-04-01

This study examines the role of educational attainment, an indicator of cognitive reserve, on transitions in later life between cognitive states (normal Mini-Mental State Examination (MMSE), mild MMSE impairment, and severe MMSE impairment) and death. Analysis of six international longitudinal studies was performed using a coordinated approach. Multistate survival models were used to estimate the transition patterns via different cognitive states. Life expectancies were estimated. Across most studies, a higher level of education was associated with a lower risk of transitioning from normal MMSE to mild MMSE impairment but was not associated with other transitions. Those with higher levels of education and socioeconomic status had longer nonimpaired life expectancies. This study highlights the importance of education in later life and that early life experiences can delay later compromised cognitive health. This study also demonstrates the feasibility and benefit in conducting coordinated analysis across multiple studies to validate findings. Copyright © 2017 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Weak independent association signals between IDE polymorphisms, Alzheimer's disease and cognitive measures.

PubMed

Mueller, Jakob C; Riemenschneider, Matthias; Schoepfer-Wendels, Andreas; Gohlke, Henning; Konta, Lidija; Friedrich, Patricia; Illig, Thomas; Laws, Simon M; Förstl, Hans; Kurz, Alexander

2007-05-01

Functional and genetic studies suggest that insulin-degrading enzyme (IDE) may be a strong functional and positional candidate. As there is a lack of consensus in regards to the level and location of IDE association signals we aimed to clarify these discrepancies through genotyping 28 SNPs in a large case-control collective together with quantitative measures of cognitive ability (MMSE). Four SNPs (rs11187007, rs2149632_ide12, rs11187033, rs11187040) were found to be associated with AD (nominal p<0.01). Tests with MMSE scores adjusted for disease duration identified associations, with the most significant result for rs1999763 (nominal p=0.008). Similarly, different reconstructed IDE haplotypes were associated with AD and higher MMSE scores. The association signals are only borderline significant after adjustment for multiple testing, but add further evidence to previous published results on the association between IDE and AD or MMSE. A subgroup analysis indicated more prominent associations with AD in younger, and with MMSE in older patients. There may be two independent effects mediated by IDE variants, risk for AD and modification of disease progression.

LS Channel Estimation and Signal Separation for UHF RFID Tag Collision Recovery on the Physical Layer.

PubMed

Duan, Hanjun; Wu, Haifeng; Zeng, Yu; Chen, Yuebin

2016-03-26

In a passive ultra-high frequency (UHF) radio-frequency identification (RFID) system, tag collision is generally resolved on a medium access control (MAC) layer. However, some of collided tag signals could be recovered on a physical (PHY) layer and, thus, enhance the identification efficiency of the RFID system. For the recovery on the PHY layer, channel estimation is a critical issue. Good channel estimation will help to recover the collided signals. Existing channel estimates work well for two collided tags. When the number of collided tags is beyond two, however, the existing estimates have more estimation errors. In this paper, we propose a novel channel estimate for the UHF RFID system. It adopts an orthogonal matrix based on the information of preambles which is known for a reader and applies a minimum-mean-square-error (MMSE) criterion to estimate channels. From the estimated channel, we could accurately separate the collided signals and recover them. By means of numerical results, we show that the proposed estimate has lower estimation errors and higher separation efficiency than the existing estimates.

Increased Muscle Sympathetic Nerve Activity and Impaired Executive Performance Capacity in Obstructive Sleep Apnea

PubMed Central

Goya, Thiago T.; Silva, Rosyvaldo F.; Guerra, Renan S.; Lima, Marta F.; Barbosa, Eline R.F.; Cunha, Paulo Jannuzzi; Lobo, Denise M.L.; Buchpiguel, Carlos A.; Busatto-Filho, Geraldo; Negrão, Carlos E.; Lorenzi-Filho, Geraldo; Ueno-Pardi, Linda M.

2016-01-01

Study Objectives: To investigate muscle sympathetic nerve activity (MSNA) response and executive performance during mental stress in obstructive sleep apnea (OSA). Methods: Individuals with no other comorbidities (age = 52 ± 1 y, body mass index = 29 ± 0.4, kg/m2) were divided into two groups: (1) control (n = 15) and (2) untreated OSA (n = 20) defined by polysomnography. Mini-Mental State of Examination (MMSE) and Inteligence quocient (IQ) were assessed. Heart rate (HR), blood pressure (BP), and MSNA (microneurography) were measured at baseline and during 3 min of the Stroop Color Word Test (SCWT). Sustained attention and inhibitory control were assessed by the number of correct answers and errors during SCWT. Results: Control and OSA groups (apnea-hypopnea index, AHI = 8 ± 1 and 47 ± 1 events/h, respectively) were similar in age, MMSE, and IQ. Baseline HR and BP were similar and increased similarly during SCWT in control and OSA groups. In contrast, baseline MSNA was higher in OSA compared to controls. Moreover, MSNA significantly increased in the third minute of SCWT in OSA, but remained unchanged in controls (P < 0.05). The number of correct answers was lower and the number of errors was significantly higher during the second and third minutes of SCWT in the OSA group (P < 0.05). There was a significant correlation (P < 0.01) between the number of errors in the third minute of SCWT with AHI (r = 0.59), arousal index (r = 0.55), and minimum O2 saturation (r = −0.57). Conclusions: As compared to controls, MSNA is increased in patients with OSA at rest, and further significant MSNA increments and worse executive performance are seen during mental stress. Clinical Trial Registration: URL: http://www.clinicaltrials.gov, registration number: NCT002289625. Citation: Goya TT, Silva RF, Guerra RS, Lima MF, Barbosa ER, Cunha PJ, Lobo DM, Buchpiguel CA, Busatto-Filho G, Negrão CE, Lorenzi-Filho G, Ueno-Pardi LM. Increased muscle sympathetic nerve activity and impaired executive performance capacity in obstructive sleep apnea. SLEEP 2016;39(1):25–33. PMID:26237773

Performance Analysis of Integrated Wireless Sensor and Multibeam Satellite Networks Under Terrestrial Interference

PubMed Central

Li, Hongjun; Yin, Hao; Gong, Xiangwu; Dong, Feihong; Ren, Baoquan; He, Yuanzhi; Wang, Jingchao

2016-01-01

This paper investigates the performance of integrated wireless sensor and multibeam satellite networks (IWSMSNs) under terrestrial interference. The IWSMSNs constitute sensor nodes (SNs), satellite sinks (SSs), multibeam satellite and remote monitoring hosts (RMHs). The multibeam satellite covers multiple beams and multiple SSs in each beam. The SSs can be directly used as SNs to transmit sensing data to RMHs via the satellite, and they can also be used to collect the sensing data from other SNs to transmit to the RMHs. We propose the hybrid one-dimensional (1D) and 2D beam models including the equivalent intra-beam interference factor β from terrestrial communication networks (TCNs) and the equivalent inter-beam interference factor α from adjacent beams. The terrestrial interference is possibly due to the signals from the TCNs or the signals of sinks being transmitted to other satellite networks. The closed-form approximations of capacity per beam are derived for the return link of IWSMSNs under terrestrial interference by using the Haar approximations where the IWSMSNs experience the Rician fading channel. The optimal joint decoding capacity can be considered as the upper bound where all of the SSs’ signals can be jointly decoded by a super-receiver on board the multibeam satellite or a gateway station that knows all of the code books. While the linear minimum mean square error (MMSE) capacity is where all of the signals of SSs are decoded singularly by a multibeam satellite or a gateway station. The simulations show that the optimal capacities are obviously higher than the MMSE capacities under the same conditions, while the capacities are lowered by Rician fading and converge as the Rician factor increases. α and β jointly affect the performance of hybrid 1D and 2D beam models, and the number of SSs also contributes different effects on the optimal capacity and MMSE capacity of the IWSMSNs. PMID:27754438

Analysis of the Bayesian Cramér-Rao lower bound in astrometry. Studying the impact of prior information in the location of an object

NASA Astrophysics Data System (ADS)

Echeverria, Alex; Silva, Jorge F.; Mendez, Rene A.; Orchard, Marcos

2016-10-01

Context. The best precision that can be achieved to estimate the location of a stellar-like object is a topic of permanent interest in the astrometric community. Aims: We analyze bounds for the best position estimation of a stellar-like object on a CCD detector array in a Bayesian setting where the position is unknown, but where we have access to a prior distribution. In contrast to a parametric setting where we estimate a parameter from observations, the Bayesian approach estimates a random object (I.e., the position is a random variable) from observations that are statistically dependent on the position. Methods: We characterize the Bayesian Cramér-Rao (CR) that bounds the minimum mean square error (MMSE) of the best estimator of the position of a point source on a linear CCD-like detector, as a function of the properties of detector, the source, and the background. Results: We quantify and analyze the increase in astrometric performance from the use of a prior distribution of the object position, which is not available in the classical parametric setting. This gain is shown to be significant for various observational regimes, in particular in the case of faint objects or when the observations are taken under poor conditions. Furthermore, we present numerical evidence that the MMSE estimator of this problem tightly achieves the Bayesian CR bound. This is a remarkable result, demonstrating that all the performance gains presented in our analysis can be achieved with the MMSE estimator. Conclusions: The Bayesian CR bound can be used as a benchmark indicator of the expected maximum positional precision of a set of astrometric measurements in which prior information can be incorporated. This bound can be achieved through the conditional mean estimator, in contrast to the parametric case where no unbiased estimator precisely reaches the CR bound.

Comparison of clock drawing with Mini Mental State Examination as a screening test in elderly acute hospital admissions.

PubMed Central

Death, J.; Douglas, A.; Kenny, R. A.

1993-01-01

Clock drawing is a quick, easy to remember test that is well received by patients. It is a good screening test for Alzheimer's disease in the outpatient setting. We evaluated its usefulness compared with the standard Mini Mental State Examination (MMSE) in elderly acute medical and surgical hospital admissions. Within 48 hours of admission, 117 patients over 70 years old were administered the MMSE and asked to draw a clock. Using the MMSE as the standard, clock drawing had a sensitivity of 77% and a specificity of 87%. Patients with discrepant scores were then further evaluated. The findings suggest that normal clock drawing ability reasonably excludes cognitive impairment or other causes of an abnormal MMSE in elderly acute medical and surgical hospital admissions, where cognitive impairment is common and frequently missed. PMID:8255833

The Telephone Interview for Cognitive Status: Creating a crosswalk with the Mini-Mental State Exam

PubMed Central

Fong, Tamara G.; Fearing, Michael A.; Jones, Richard N.; Shi, Peilin; Marcantonio, Edward R.; Rudolph, James L.; Yang, Frances M.; Kiely, Dan K.; Inouye, Sharon K.

2009-01-01

Background Brief cognitive screening measures are valuable tools for both research and clinical applications. The most widely used instrument, the Mini-Mental State Examination (MMSE) is limited in that it must be administered face-to-face, cannot be used in participants with visual or motor impairments, and is protected by copyright. Alternative screening instruments, such as the Telephone Interview for Cognitive Status (TICS) have been developed and may provide a valid alternative with comparable cut point scores to rate global cognitive function. Methods MMSE, TICS-30, and TICS-40 scores from 746 community dwelling elders who participated in the Aging, Demographics, and Memory Study (ADAMS) were analyzed with equipercentile equating, a statistical process of determining comparable scores based on percentile equivalents on different forms of an examination. Results Scores from the MMSE and the TICS-30 and TICS-40 corresponded well and clinically relevant cut point scores were determined; for example, an MMSE score of 23 is equivalent to 17 and 20 on the TICS-30 and TICS-40, respectively. Conclusions These findings provide scores that can be used to link TICS and MMSE scores directly. Clinically relevant and important MMSE cut points and the respective ADAMS TICS-30 and TICS-40 cut point scores have been included to identify the degree of cognitive impairment among respondents with any type of cognitive disorder. These results will help with the widespread application of the TICS in both research and clinical practice. PMID:19647495

Factors Influencing Cognitive Function in Subjects With COPD.

PubMed

Dag, Ersel; Bulcun, Emel; Turkel, Yakup; Ekici, Aydanur; Ekici, Mehmet

2016-08-01

The aim of this study was to assess the association between cognitive function and age, pulmonary function, comorbidity index, and the 6-min walk distance in subjects with COPD as well as to compare the Mini Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) in terms of their ability to identify cognitive dysfunction in subjects with COPD. A total of 52 individuals with stable COPD were included in this study. Cognitive function was assessed using MMSE and MoCA. Age, body mass index, the Modified Cumulative Illness Rating Scale, 6-min walk distance, arterial blood gases, and pulmonary function tests were assessed and recorded. The range and SD of scores in subjects with COPD were larger with MoCA than with MMSE. MMSE and MoCA scores are associated with 6-min walk distance and comorbidity index in subjects with COPD. General cognitive function measured by MoCA was negatively correlated with the comorbidity index but was positively associated with 6-min walk distance in subjects with COPD after controlling for possible confounding factors in the multivariate model. However, general cognitive function measured by MMSE was not correlated with the comorbidity index and 6-min walk distance in subjects with COPD, after controlling for possible confounding factors in the multivariate model. MoCA may be a more reliable screening test than MMSE in detecting cognitive impairment in subjects with COPD. The addition of cognitive tests on assessment of subjects with COPD can provide further benefit. Copyright © 2016 by Daedalus Enterprises.

Montreal Cognitive Assessment (MoCA): validation study for frontotemporal dementia.

PubMed

Freitas, Sandra; Simões, Mário R; Alves, Lara; Duro, Diana; Santana, Isabel

2012-09-01

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

Control of adaptive optic element displacement with the help of a magnetic rheology drive

NASA Astrophysics Data System (ADS)

Deulin, Eugeni A.; Mikhailov, Valeri P.; Sytchev, Victor V.

2000-10-01

The control system of adaptive optic of a large astronomical segmentated telescope was designed and tested. The dynamic model and the amplitude-frequency analysis of the new magnetic rheology (MR) drive are presented. The loop controlled drive consists of hydrostatic carrier, MR hydraulic loop controlling system, elastic thin wall seal, stainless seal which are united in a single three coordinate manipulator. This combination ensures short positioning error (delta) (phi)

Associations of cumulative Pb exposure and longitudinal changes in Mini-Mental Status Exam scores, global cognition and domains of cognition: The VA Normative Aging Study

PubMed Central

Farooqui, Zishaan; Bakulski, Kelly M.; Power, Melinda C.; Weisskopf, Marc G.; Sparrow, David; Spiro, Avron; Vokonas, Pantel S.; Nie, Huiling; Hu, Howard; Park, Sung Kyun

2016-01-01

Background Lead (Pb) exposure has been associated with poorer cognitive function cross-sectionally in aging adults, however the association between cumulative Pb exposure and longitudinal changes in cognition is little characterized. Methods In a 1993–2007 subcohort of the VA Normative Aging Study (Mini-mental status exam (MMSE) n=741; global cognition summary score n=715), we used linear mixed effects models to test associations between cumulative Pb exposure (patella or tibia bone Pb) and repeated measures of cognition (MMSE, individual cognitive tests, and global cognition summary). Cox proportional hazard modeling assessed the risk of an MMSE score falling below 25. Results Among men 51–98 at baseline, higher patella Pb concentration (IQR: 21 µg/g) was associated with −0.13 lower baseline MMSE (95% CI: −0.25, −0.004) and faster longitudinal MMSE decline (−0.016 units/year, 95% CI: −0.032, −0.0004) over 15 years. Each IQR increase in patella Pb was associated with increased risk of a MMSE score below 25 (HR=1.21, 95% CI: 0.99, 1.49; p=0.07). There were no significant associations between Pb and global cognition (both baseline and longitudinal change). Patella Pb was associated with faster longitudinal decline in Word List Total Recall in the language domain (0.014 units/year, 95% CI: −0.026, −0.001) and Word List Delayed Recall in the memory domain (0.014 units/year, 95% CI: −0.027, −0.002). We found weaker associations with tibia Pb. Conclusions Cumulative Pb exposure is associated with faster declines in MMSE and Word List Total and Delayed Recall tests. These findings support the hypothesis that Pb exposure accelerates cognitive aging. PMID:27770710

Converting MMSE to MoCA and MoCA 5-minute protocol in an educationally heterogeneous sample with stroke or transient ischemic attack.

PubMed

Wong, Adrian; Black, Sandra E; Yiu, Stanley Y P; Au, Lisa W C; Lau, Alexander Y L; Soo, Yannie O Y; Chan, Anne Y Y; Leung, Thomas W H; Wong, Lawrence K S; Kwok, Timothy C Y; Cheung, Theodore C K; Leung, Kam-Tat; Lam, Bonnie Y K; Kwan, Joseph S K; Mok, Vincent C T

2018-05-01

The Montreal Cognitive Assessment (MoCA) is psychometrically superior over the Mini-mental State Examination (MMSE) for cognitive screening in stroke or transient ischemic attack (TIA). It is free for clinical and research use. The objective of this study is to convert scores from the MMSE to MoCA and MoCA-5-minute protocol (MoCA-5 min) and to examine the ability of the converted scores in detecting cognitive impairment after stroke or TIA. A total of 904 patients were randomly divided into training (n = 623) and validation (n = 281) samples matched for demography and cognition. MMSE scores were converted to MoCA and MoCA-5 min using (1) equipercentile method with log-linear smoothing and (2) Poisson regression adjusting for age and education. Receiver operating characteristics curve analysis was used to examine the ability of the converted scores in differentiating patients with cognitive impairment. The mean education was 5.8 (SD = 4.6; ranged 0-20) years. The entire spectrum of MMSE scores was converted to MoCA and MoCA-5 min using equipercentile method. Relationship between MMSE and MoCA scores was confounded by age and education, and a conversion equation with adjustment for age and education was derived. In the validation sample, the converted scores differentiated cognitively impaired patients with area under receiver operating characteristics curve 0.826 to 0.859. We provided 2 methods to convert scores from the MMSE to MoCA and MoCA-5 min based on a large sample of patients with stroke or TIA having a wide range of education and cognitive levels. The converted scores differentiated patients with cognitive impairment after stroke or TIA with high accuracy. Copyright © 2018 John Wiley & Sons, Ltd.

Trade-Offs in a 1 Tbps Multiple-Input and Multiple-Output (MIMO) Communication System Between an Airship and Ground Receive Antennas

DTIC Science & Technology

2012-03-01

covariance PT T Ir, where R is the number of receive antennas. The capacity is given by B × log2 ∣ ∣Ir + PT T HHH ∣ ∣. From his theorem, Telatar stated that...Applying Telatar’s theorem to 2.9, the capacity for a MIMO system can be rewritten as C = B log2 ∣ ∣ ∣ ∣ I+ PT T HHH ∣ ∣ ∣ ∣ , (2.13) where I is the identity...as a MMSE equalizer and is modeled as H† = ( HHH + σ2 n I)−1HH, (2.39) where H is the channel gain matrix, σ2n is the SNR per transmit antenna, x H

Shapes of the Trajectories of Five Major Biomarkers of Alzheimer’s Disease

PubMed Central

Jack, Clifford R.; Vemuri, Prashanthi; Wiste, Heather J.; Weigand, Stephen D.; Lesnick, Timothy G.; Lowe, Val; Kantarci, Kejal; Bernstein, Matt A.; Senjem, Matthew L.; Gunter, Jeffrey L.; Boeve, Bradley F.; Trojanowski, John Q.; Shaw, Leslie M.; Aisen, Paul S.; Weiner, Michael W.; Petersen, Ronald C.; Knopman, David S.

2013-01-01

Objective To characterize the shape of the trajectories of Alzheimer’s Disease (AD) biomarkers as a function of MMSE. Design Longitudinal registries from the Mayo Clinic and the Alzheimer’s Disease Neuroimaging Initiative (ADNI). Patients Two different samples (n=343 and n=598) were created that spanned the cognitive spectrum from normal to AD dementia. Subgroup analyses were performed in members of both cohorts (n=243 and n=328) who were amyloid positive at baseline. Main Outcome Measures The shape of biomarker trajectories as a function of MMSE, adjusted for age, was modeled and described as baseline (cross-sectional) and within-subject longitudinal effects. Biomarkers evaluated were cerebro spinal fluid (CSF) Aβ42 and tau; amyloid and fluoro deoxyglucose position emission tomography (PET) imaging, and structural magnetic resonance imaging (MRI). Results Baseline biomarker values generally worsened (i.e., non-zero slope) with lower baseline MMSE. Baseline hippocampal volume, amyloid PET and FDG PET values plateaued (i.e., non-linear slope) with lower MMSE in one or more analyses. Longitudinally, within-subject rates of biomarker change were associated with worsening MMSE. Non-constant within-subject rates (deceleration) of biomarker change were found in only one model. Conclusions Biomarker trajectory shapes by MMSE were complex and were affected by interactions with age and APOE status. Non-linearity was found in several baseline effects models. Non-constant within-subject rates of biomarker change were found in only one model, likely due to limited within-subject longitudinal follow up. Creating reliable models that describe the full trajectories of AD biomarkers will require significant additional longitudinal data in individual participants. PMID:22409939

Microbleeds do not affect rate of cognitive decline in Alzheimer disease.

PubMed

van der Vlies, Annelies E; Goos, Jeroen D C; Barkhof, Frederik; Scheltens, Philip; van der Flier, Wiesje M

2012-08-21

To investigate the relationship between brain microbleeds (MBs) and the rate of cognitive decline in Alzheimer disease (AD). In this cohort study, we studied 221 patients with AD with available baseline MRI scans (1.0 or 1.5 T) and at least 2 Mini-Mental State Examinations (MMSE) scores obtained more than 1 year apart from our memory clinic. Mean ± SD follow-up time was 3 ± 1 years, and patients had a median of 4 MMSE scores (range 2-17). We used linear mixed models with sex and age as covariates to investigate whether MBs influenced the rate of cognitive decline. Mean age was 68 ± 9 years, 109 (49%) patients were female, and the baseline MMSE score was 22 ± 4. There were 39 patients (18%) with MBs (median 2, range 1-27) and 182 without. Linear mixed models showed that overall patients declined 2 MMSE points per year. We found no association of the presence of MBs with baseline MMSE or change in MMSE. Adjustment for atrophy, white matter hyperintensities, lacunes, and vascular risk factors did not change the results nor did stratification for MB location, APOE ε4 carriership, or age at onset (≤65 years vs >65 years). Repeating the analyses with number of MBs as predictor rendered similar results. MBs did not influence the rate of cognitive decline in patients with AD. The formerly reported increased risk of mortality in patients with MBs seems not to be attributable to a steeper rate of decline per se but might be due to vascular events, including (hemorrhagic) stroke.

Validity of a semantically cued recall procedure for the mini-mental state examination.

PubMed

Yuspeh, R L; Vanderploeg, R D; Kershaw, D A

1998-10-01

The validity of supplementing the three-item recall portion of the Mini-Mental State Examination (MMSE) with a cued recall procedure to help specify the nature of patients' memory problems was examined. Subjects were 247 individuals representing three diagnostic groups: Alzheimer's disease (AD), subcortical vascular ischemic dementia (SVaD), and normal controls. Individuals were administered a battery of neuropsychological tests, including the MMSE, as part of a comprehensive evaluation for the presence of dementia or other neurologic disorder. MMSE performance differed among groups. The three-item free recall performance also differed among groups, with post hoc analyses revealing the AD and SVaD groups were more impaired than controls but did not differ significantly from each other. Following a cued recall procedure of the MMSE three-items, groups differed, with post hoc analyses showing that AD patients failed to benefit from cues, whereas SVaD patients performed significantly better and comparable to control subjects. Significant correlations between the MMSE three-item cued recall performance and other memory measures demonstrated concurrent validity. Consistent with previous research indicating that SVaD is associated with memory encoding and retrieval deficits, whereas AD is associated with consolidation and storage problems, the present study supported the validity of the cued recall procedure of the three items on the MMSE in helping to distinguish between patients with AD and those with a vascular dementia with primarily subcortical pathology; however, despite these findings, a more extensive battery of neuropsychological measures is still recommended to consistently assess subtle diagnostic differences in these memory processes.

Describing the Sequence of Cognitive Decline in Alzheimer's Disease Patients: Results from an Observational Study.

PubMed

Henneges, Carsten; Reed, Catherine; Chen, Yun-Fei; Dell'Agnello, Grazia; Lebrec, Jeremie

2016-01-01

Improved understanding of the pattern of cognitive decline in Alzheimer's disease (AD) would be useful to assist primary care physicians in explaining AD progression to patients and caregivers. To identify the sequence in which cognitive abilities decline in community-dwelling patients with AD. Baseline data were analyzed from 1,495 patients diagnosed with probable AD and a Mini-Mental State Examination (MMSE) score ≤ 26 enrolled in the 18-month observational GERAS study. Proportional odds logistic regression models were applied to model MMSE subscores (orientation, registration, attention and concentration, recall, language, and drawing) and the corresponding subscores of the cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-cog), using MMSE total score as the index of disease progression. Probabilities of impairment start and full impairment were estimated at each MMSE total score level. From the estimated probabilities for each MMSE subscore as a function of the MMSE total score, the first aspect of cognition to start being impaired was recall, followed by orientation in time, attention and concentration, orientation in place, language, drawing, and registration. For full impairment in subscores, the sequence was recall, drawing, attention and concentration, orientation in time, orientation in place, registration, and language. The sequence of cognitive decline for the corresponding ADAS-cog subscores was remarkably consistent with this pattern. The sequence of cognitive decline in AD can be visualized in an animation using probability estimates for key aspects of cognition. This might be useful for clinicians to set expectations on disease progression for patients and caregivers.

Cereal Intake Increases and Dairy Products Decrease Risk of Cognitive Decline among Elderly Female Japanese.

PubMed

Otsuka, R; Kato, Y; Nishita, Y; Tange, C; Nakamoto, M; Tomida, M; Imai, T; Ando, F; Shimokata, H

2014-01-01

If cognitive decline can be prevented through changes in daily diet with no medical intervention, it will be highly significant for dementia prevention. This longitudinal study examined the associations of different food intakes on cognitive decline among Japanese subjects. Prospective cohort study. The National Institute for Longevity Sciences - Longitudinal Study of Aging, a community-based study. Participants included 298 males and 272 females aged 60 to 81 years at baseline who participated in the follow-up study (third to seventh wave) at least one time. Cognitive function was assessed with the Mini-Mental State Examination (MMSE) in all study waves. Nutritional intake was assessed using a 3-day dietary record in the second wave. Cumulative data among participants with an MMSE >27 in the second wave were analyzed using a generalized estimating equation. Multivariate adjusted odds ratios (OR) and 95% confidence intervals (CI) for an MMSE score ≤27 in each study wave according to a 1 standard deviation (SD) increase of each food intake at baseline were estimated, after adjusting for age, follow-up time, MMSE score at baseline, education, body mass index, annual household income, current smoking status, energy intake, and history of diseases. In men, after adjusting for age, and follow-up period, MMSE score at baseline, the adjusted OR for a decline in MMSE score was 1.20 (95% CI, 1.02-1.42; p=0.032) with a 1-SD increase in cereal intake. After adjusting for education and other confounding variables, the OR for a decrease in MMSE score did not reach statistical significance for this variable. In women, multivariate adjusted OR for MMSE decline was 1.43 (95% CI, 1.15-1.77; p=0.001) with a 1-SD increase in cereal intake and 0.80 (95% CI, 0.65-0.98; p=0.034) with a 1-SD increase in milk and dairy product intake. This study indicates that a 1-SD (108 g/day) decrease in cereal intake and a 1-SD (128 g/day) increase in milk and dairy product intake may have an influence of cognitive decline in community-dwelling Japanese women aged 60 years and older. Further studies are needed in order to explore the potential causal relationship.

Beamforming Based Full-Duplex for Millimeter-Wave Communication

PubMed Central

Liu, Xiao; Xiao, Zhenyu; Bai, Lin; Choi, Jinho; Xia, Pengfei; Xia, Xiang-Gen

2016-01-01

In this paper, we study beamforming based full-duplex (FD) systems in millimeter-wave (mmWave) communications. A joint transmission and reception (Tx/Rx) beamforming problem is formulated to maximize the achievable rate by mitigating self-interference (SI). Since the optimal solution is difficult to find due to the non-convexity of the objective function, suboptimal schemes are proposed in this paper. A low-complexity algorithm, which iteratively maximizes signal power while suppressing SI, is proposed and its convergence is proven. Moreover, two closed-form solutions, which do not require iterations, are also derived under minimum-mean-square-error (MMSE), zero-forcing (ZF), and maximum-ratio transmission (MRT) criteria. Performance evaluations show that the proposed iterative scheme converges fast (within only two iterations on average) and approaches an upper-bound performance, while the two closed-form solutions also achieve appealing performances, although there are noticeable differences from the upper bound depending on channel conditions. Interestingly, these three schemes show different robustness against the geometry of Tx/Rx antenna arrays and channel estimation errors. PMID:27455256

Self-administered Gerocognitive Examination (SAGE): a brief cognitive assessment Instrument for mild cognitive impairment (MCI) and early dementia.

PubMed

Scharre, Douglas W; Chang, Shu-Ing; Murden, Robert A; Lamb, James; Beversdorf, David Q; Kataki, Maria; Nagaraja, Haikady N; Bornstein, Robert A

2010-01-01

To develop a self-administered cognitive assessment instrument to facilitate the screening of mild cognitive impairment (MCI) and early dementia and determine its association with gold standard clinical assessments including neuropsychologic evaluation. Adults aged above 59 years with sufficient vision and English literacy were recruited from geriatric and memory disorder clinics, educational talks, independent living facilities, senior centers, and memory screens. After Self-administered Gerocognitive Examination (SAGE) screening, subjects were randomly selected to complete a clinical evaluation, neurologic examination, neuropsychologic battery, functional assessment, and mini-mental state examination (MMSE). Subjects were identified as dementia, MCI, or normal based on standard clinical criteria and neuropsychologic testing. Two hundred fifty-four participants took the SAGE screen and 63 subjects completed the extensive evaluation (21 normal, 21 MCI, and 21 dementia subjects). Spearman rank correlation between SAGE and neuropsychologic battery was 0.84 (0.76 for MMSE). SAGE receiver operating characteristics on the basis of clinical diagnosis showed 95% specificity (90% for MMSE) and 79% sensitivity (71% for MMSE) in detecting those with cognitive impairment from normal subjects. This study suggests that SAGE is a reliable instrument for detecting cognitive impairment and compares favorably with the MMSE. The self-administered feature may promote cognitive testing by busy clinicians prompting earlier diagnosis and treatment.

A comparative study of behavioral and psychological symptoms of dementia in patients with Alzheimer's disease and vascular dementia referred to psychogeriatric services in Korea and the U.K.

PubMed

Shah, Ajit; Ellanchenny, Nalini; Suh, Guk-Hee

2005-06-01

There is a paucity of cross-cultural studies of behavioral and psychological symptoms of dementia (BPSD). BPSD were examined in consecutive series of referrals to a psychogeriatric service in Korea and the U.K. using the Behavioral Pathology in Alzheimer's Disease (BEHAVE-AD) rating scale and the Cornell Scale for Depression in Dementia (CSDD). Results were analyzed separately for Alzheimer's disease and vascular dementia. Koreans in both diagnostic groups had lower Mini-mental State Examination (MMSE) scores and higher BEHAVE-AD total and subscale scores for most subscales. In both countries, for both diagnostic groups, the total BEHAVE-AD score and several subscale scores were negatively correlated with the MMSE scores. Logistic regression analysis for Alzheimer's disease revealed that BEHAVE-AD total and most subscale scores independently predicted the country of origin in addition to the MMSE scores predicting the same. These differences in BPSD are most likely explained by the lower MMSE scores in the Korean sample. However, genuine differences in BPSD between the two countries can only be critically examined in a cross-cultural population-based epidemiological study for both diagnostic categories using validated instruments to measure BPSD and controlling for the influence of MMSE score.

Mini-Mental State Exam performance of older African Americans: effect of age, gender, education, hypertension, diabetes, and the inclusion of serial 7s subtraction versus "world" backward on score.

PubMed

Hawkins, Keith A; Cromer, Jennifer R; Piotrowski, Andrea S; Pearlson, Godfrey D

2011-11-01

The Mini-Mental State Exam (MMSE) is a clinically ubiquitous yet incompletely standardized instrument. Though the test offers considerable examiner leeway, little data exist on the normative consequences of common administration variations. We sought to: (a) determine the effects of education, age, gender, health status, and a common administration variation (serial 7s subtraction vs. "world" spelled backward) on MMSE score within a minority sample, (b) provide normative data stratified on the most empirically relevant bases, and (c) briefly address item failure rates. African American citizens (N = 298) aged 55-87 living independently in the community were recruited by advertisement, community recruitment, and word of mouth. Total score with "world" spelled backward exceeded total score with serial 7s subtraction across all levels of education, replicating findings in Caucasian samples. Education is the primary source of variance on MMSE score, followed by age. In this cohort, women out-performed men when "world" spelled backward was included, but there was no gender effect when serial 7s subtraction was included in MMSE total score. To ensure an appropriate interpretation of MMSE scores, reports, whether clinical or in publications of research findings, should be explicit regarding the administration method. Stratified normative data are provided.

[Association between cerumen impaction, cognitive function and hearing in Japanese elderly].

PubMed

Sugiura, Saiko; Uchida, Yasue; Nakashima, Tsutomu; Nishita, Yukiko; Tange, Chikako; Ando, Fujiko; Shimokata, Hiroshi

2012-01-01

In this study we aimed to evaluate the frequency of cerumen impaction in Japanese elderly and clarify the associations between cerumen, cognitive function, and hearing impairment. The subjects enrolleded in this study were participants in the National Institute for Longevity Sciences, Longitudinal Study of Aging (NILS-LSA). The data of 792 community-dwelling participants aged 60 to 88 years old were collected. All had taken the Mini-Mental State Examination (MMSE) and had undergone pure tone audiometry (PTA) assessment and video recording of an otoscopic examination. We then analyzed associations between the incidence of the cerumen impaction of better-hearing ear, hearing level and MMSE scores using a general linear model. Cerumen impaction of the better-hearing ear was observed in 10.7% of all participants. In participants with an MMSE score of less than 24, the frequency of cerumen impaction was 23.3%. Cerumen was significant associated with poorer hearing after adjustment for sex and age (p=0.0001). Cerumen impaction also showed a significant association with a low MMSE score after adjustment for sex, age, hearing level and education (p=0.02). The frequency of cerumen impaction in Japanese elderly was estimated to be approximately 10%. The existence of cerumen impaction was associated with poorer hearing level and lower MMSE score.

Evaluation of the Addenbrooke's Cognitive Examination's validity in a brain injury rehabilitation setting.

PubMed

Gaber, Tarek A-Z K

2008-07-01

Several reports have warned of the Mini Mental State Examination's (MMSE) inability to detect gross memory and high executive impairments. Addenbrooke's Cognitive Examination-Revised (ACE-R) has gained enormous popularity in dementia screening as it addresses the main shortcomings of MMSE. This study aimed at evaluating the use of ACE-R and to establish its sensitivity compared to MMSE in a cohort of brain injury patients. ACE-R was administered to a cohort of chronic brain injury patients. All patients had a cognitive impairment which was severe enough to prevent them working or studying. Patients with significant mental health, sensory, communication or physical impairments were excluded. Thirty-six patients were recruited, 31 males with a mean age of 37 years. For an upper cut-off value of 27/30 for MMSE and 88/100 for ACE-R, their sensitivities were 36% and 72%, respectively. For a lower cut-off value of 24/30 and 82/100 the tests sensitivities were 11% and 56%, respectively. Analysis of the ACE-R sub-tests indicated that memory and verbal fluency sub-tests showed the most dramatic impairment. MMSE is insensitive as a screening test in brain injury patients. The results show ACE-R to be a sensitive, easily administered test.

Interleukin-6 is associated with cognitive function: the Northern Manhattan Study

PubMed Central

Wright, C.B.; Sacco, R.L.; Rundek, T.R.; Delman, J.B.; Rabbani, L.E.; Elkind, M.S.V.

2006-01-01

Background and purpose Inflammation has been linked to cognitive decline and dementia but the mechanism is not clear and few studies have included Hispanic and black subjects that may be at increased risk of these disorders. Methods We performed a cross-sectional analysis of the association between inflammatory marker levels and cognition in the stroke-free population-based cohort of the Northern Manhattan Study. Mini Mental State Exam (MMSE) scores were the continuous outcome and we adjusted for sociodemographic and vascular risk factors as well as subclinical atherosclerosis. Results Of the inflammatory markers, only interleukin (IL)-6 levels were associated with the MMSE. In univariate analysis age, hypertension, diabetes, smoking, moderate alcohol use, total homocysteine, carotid intima media thickness, and body mass index were positively associated with IL-6 levels. Hispanics compared to whites, those with less than a high school education, hypertension, cardiac disease, and total homocysteine were associated with lower MMSE scores. In a multivariate linear regression model, IL-6 was negatively associated with MMSE score adjusting for sociodemographic and vascular risk factors. Conclusions IL-6 levels were negatively associated with performance on the MMSE in this multiethnic cohort. Adjusting for vascular disease and subclinical atherosclerosis did not attenuate the association, suggesting a direct effect on the brain. PMID:16501663

Equalization for a page-oriented optical memory system

NASA Astrophysics Data System (ADS)

Trelewicz, Jennifer Q.; Capone, Jeffrey

1999-11-01

In this work, a method of decision-feedback equalization is developed for a digital holographic channel that experiences moderate-to-severe imaging errors. Decision feedback is utilized, not only where the channel is well-behaved, but also near the edges of the camera grid that are subject to a high degree of imaging error. In addition to these effects, the channel is worsened by typical problems of holographic channels, including non-uniform illumination, dropouts, and stuck bits. The approach described in this paper builds on established methods for performing trained and blind equalization on time-varying channels. The approach is tested on experimental data sets. On most of these data sets, the method of equalization described in this work delivers at least an order of magnitude improvement in bit-error rate (BER) before error-correction coding (ECC). When ECC is introduced, the approach is able to recover stored data with no errors for many of the tested data sets. Furthermore, a low BER was maintained even over a range of small alignment perturbations in the system. It is believed that this equalization method can allow cost reductions to be made in page-memory systems, by allowing for a larger image area per page or less complex imaging components, without sacrificing the low BER required by data storage applications.

Delayed Recall and Working Memory MMSE Domains Predict Delirium following Cardiac Surgery.

PubMed

Price, Catherine C; Garvan, Cynthia; Hizel, Loren P; Lopez, Marcos G; Billings, Frederic T

2017-01-01

Reduced preoperative cognition is a risk factor for postoperative delirium. The significance for type of preoperative cognitive deficit, however, has yet to be explored and could provide important insights into mechanisms and prediction of delirium. Our goal was to determine if certain cognitive domains from the general cognitive screener, the Mini-Mental State Exam (MMSE), predict delirium after cardiac surgery. Patients completed a preoperative MMSE prior to undergoing elective cardiac surgery. Following surgery, delirium was assessed throughout ICU stay using the Confusion Assessment Method for ICU delirium and the Richmond Agitation and Sedation Scale. Cardiac surgery patients who developed delirium (n = 137) had lower total MMSE scores than patients who did not develop delirium (n = 457). In particular, orientation to place, working memory, delayed recall, and language domain scores were lower. Of these, only the working memory and delayed recall domains predicted delirium in a regression model adjusting for history of chronic obstructive pulmonary disease, age, sex, and duration of cardiopulmonary bypass. For each word not recalled on the three-word delayed recall assessment, the odds of delirium increased by 50%. For each item missed on the working memory index, the odds of delirium increased by 36%. Of the patients who developed delirium, 47% had a primary impairment in memory, 21% in working memory, and 33% in both domains. The area under the receiver operating characteristics curve using only the working memory and delayed recall domains was 0.75, compared to 0.76 for total MMSE score. Delirium risk is greater for individuals with reduced MMSE scores on the delayed recall and working memory domains. Research should address why patients with memory and executive vulnerabilities are more prone to postoperative delirium than those with other cognitive limitations.

Comparison of two commonly used clinical cognitive screening tests to diagnose mild cognitive impairment in heart failure with the golden standard European Consortium Criteria.

PubMed

Alagiakrishnan, Kannayiram; Mah, Darren; Dyck, Jason R B; Senthilselvan, Ambikaipakan; Ezekowitz, Justin

2017-02-01

This study on mild cognitive impairment (MCI) in heart failure (HF) compares the utility of Montreal Cognitive Assessment (MoCA) to the Mini-Mental Status Exam (MMSE) for diagnosing MCI in a HF population when compared to the golden standard European Consortium Criteria (ECC). Participants were recruited from the Alberta HEART study at the Mazankowski Alberta Heart Institute in Edmonton and St. Mary's hospital in Camrose. This study enrolled 53 community adults aged>50years: 33 HF and 20 controls. Participants were assessed using both the MMSE and MoCA for MCI. MCI was diagnosed using the golden standard, European Consortium Criteria. Sensitivity and specificity analysis, positive and negative predictive values, likelihood ratios and kappa statistic were calculated. The mean age was 72.8years (SD 8.4), 60.4% were females and 34% had underlying ischemic heart disease. Overall, two thirds of patients (22/33, 66%) with HF had MCI. In comparison to European Consortium Criteria, the sensitivity and specificity of MoCA were 82% and 91% in identifying individuals with MCI, and MMSE were 9% and 91%, respectively. The positive and negative predictive values for MoCA were 95% and 71%, and for MMSE were 67% and 33%, respectively. Kappa statistics showed good agreement between MoCA and consortium criteria (kappa=0.68) and a low agreement between MMSE and consortium criteria (kappa=0.07). Cognitive dysfunction is common in patients with HF. Overall, the MoCA seems to be a better screening tool than MMSE for MCI in HF patients. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

[Influence of habitual chocolate consumption over the Mini-Mental State Examination in Spanish older adults].

PubMed

Orozco Arbelaez, Edilbeto; Banegas, José Ramón; Rodríguez Artalejo, Fernando; López García, Esther

2017-07-28

There are associations described between dementia, mild cognitive impairment (MCI) and foods with a high content of polyphenols. To assess the infl uence of habitual chocolate consumption over the MMSE in Spanish older adults. Cross-sectional study, using data of the follow-up of the Seniors-Study on Nutrition and Cardiovascular Risk in Spain (ENRICA) cohort. Habitual chocolate consumption in the last year was assessed with a computerized dietary history; differences between dark chocolate and milk chocolate were recorded. Chocolate intake was classified into the following categories: no consumption, < 10 g/day, and ≥ 10 g/day. Validated MMSE scores for Spain were obtained during an interview and different cutoff points were used to define ≤ 25, ≤ 24 and ≤ 23. Linear and logistic regression models were used to calculate adjusted beta coefficients and odds ratios (OR). Compared to non-consumers, participants with a habitual chocolate consumption of ≥ 10 g/d had a better MMSE score (adjusted beta coefficient and 95% confidence interval: 0.26 (0.02-0.50; p trend = 0.05); for dark chocolate, the results were also statistically significant (0.48 [0.18-0.78]; p trend < 0.001). Total chocolate consumption was not associated with higher likelihood of having MCI. However, dark chocolate consumption was associated with less likelihood of MCI (OR and 95%CI for MMSE ≤ 25: 0.39 [0.20-0.77]; for MMSE ≤ 24: 0.26 [0.10-0.67]; and for MMSE ≤ 23: 0.25 [0.07-0.82]). Our results suggest that habitual dark chocolate consumption might improve cognitive function among the older population.

Cognitive impairment, the Mini-Mental State Examination and socio-demographic and dental variables in the elderly in Brazil.

PubMed

Miranda, Leonardo de Paula; Silveira, Marise F; Oliveira, Thatiane L; Alves, Sâmia F F; Júnior, Hercílio M; Batista, André U D; Bonan, Paulo R F

2012-06-01

Dementia, a syndrome characterised by multiple cognitive impairments, is an increasing medical and social problem across the world. The Mini-Mental State Examination (MMSE) is the instrument most often used in the evaluation of cognitive compromise and dementia in elderly individuals. It is noteworthy that there is a scarcity of works in the literature on the dimensions of the MMSE and its relation to dental variables in the elderly. To evaluate the condition of cognitive impairment, the dimensions of the MMSE, and the latter's relation to socio-demographic and dental variables in elderly individuals of Montes Claros, Minas Gerais, Brazil. This is a cross-sectional descriptive study, whereby 218 elderly users of the system were evaluated at the Sistema Único de Saúde (Brazilian health service) in Montes Claros. The collection of data involved the realisation of structured interviews and clinical dentistry examinations. The screening of cognitive impairment was carried out with the Portuguese version of MMSE. The data were subjected to descriptive and bivariate analyses. The prevalence of cognitive impairment found was 6.4%. A statistically significant association was observed between cognitive decline and age, marital status and use of dental prostheses. An association was also noted between several dimensions of MMSE and edentulism (time orientation, attention and calculation, and final score) and use of prostheses (except evocation memory and language). It was noticed that those who were 80 years old or more, not married and using prostheses were more likely to manifest cognitive impairment. Associations between some MMSE dimensions were established, including the final score, with edentulism and the use of prostheses. © 2011 The Gerodontology Society and John Wiley & Sons A/S.

Methylphenidate hydrochloride improves cognitive function in patients with advanced cancer and hypoactive delirium: a prospective clinical study

PubMed Central

Gagnon, Bruno; Low, Graeme; Schreier, Gil

2005-01-01

Objective To investigate the clinical improvement observed in patients with advanced cancer and hypoactive delirium after the administration of methylphenidate hydrochloride. Methods Fourteen patients with advanced cancer and hypoactive delirium were seen between March 1999 and August 2000 at the Palliative Care Day Hospital and the inpatient Tertiary Palliative Care Unit of Montreal General Hospital, Montréal. They were chosen for inclusion in a prospective clinical study on the basis of (1) cognitive failure documented by the Mini-Mental State Examination (MMSE), (2) sleep–wake pattern disturbances, (3) psychomotor retardation, (4) absence of delusions or hallucinations, and (5) absence of an underlying cause to explain the delirium. All patients were treated with methylphenidate, and changes in their cognitive function were measured using the MMSE. Results All 14 patients showed improvement in their cognitive function as documented by the MMSE. The median pretreatment MMSE score (maximum score 30) was 21 (mean 20.9, standard deviation [SD] 4.9), which improved to a median of 27 (mean 24.9, SD 4.7) after the first dose of methylphenidate (p < 0.001, matched, paired Wilcoxon signed rank test). One patient died before reaching a stable dose of methylphenidate. In the other 13 patients, the median MMSE score further improved to 28 (mean 27.8, SD 2.4) (p = 0.02 compared with the median MMSE score documented 1 hour after the first dose of methylphenidate). All patients showed an improvement in psychomotor activities. Conclusions Hypoactive delirium that cannot be explained by an underlying cause (metabolic or drug-induced) in patients with advanced cancer appears to be a specific syndrome that could be improved by the administration of methylphenidate. PMID:15798785

Three-class ROC analysis--the equal error utility assumption and the optimality of three-class ROC surface using the ideal observer.

PubMed

He, Xin; Frey, Eric C

2006-08-01

Previously, we have developed a decision model for three-class receiver operating characteristic (ROC) analysis based on decision theory. The proposed decision model maximizes the expected decision utility under the assumption that incorrect decisions have equal utilities under the same hypothesis (equal error utility assumption). This assumption reduced the dimensionality of the "general" three-class ROC analysis and provided a practical figure-of-merit to evaluate the three-class task performance. However, it also limits the generality of the resulting model because the equal error utility assumption will not apply for all clinical three-class decision tasks. The goal of this study was to investigate the optimality of the proposed three-class decision model with respect to several other decision criteria. In particular, besides the maximum expected utility (MEU) criterion used in the previous study, we investigated the maximum-correctness (MC) (or minimum-error), maximum likelihood (ML), and Nyman-Pearson (N-P) criteria. We found that by making assumptions for both MEU and N-P criteria, all decision criteria lead to the previously-proposed three-class decision model. As a result, this model maximizes the expected utility under the equal error utility assumption, maximizes the probability of making correct decisions, satisfies the N-P criterion in the sense that it maximizes the sensitivity of one class given the sensitivities of the other two classes, and the resulting ROC surface contains the maximum likelihood decision operating point. While the proposed three-class ROC analysis model is not optimal in the general sense due to the use of the equal error utility assumption, the range of criteria for which it is optimal increases its applicability for evaluating and comparing a range of diagnostic systems.

EMG Versus Torque Control of Human-Machine Systems: Equalizing Control Signal Variability Does not Equalize Error or Uncertainty.

PubMed

Johnson, Reva E; Kording, Konrad P; Hargrove, Levi J; Sensinger, Jonathon W

2017-06-01

In this paper we asked the question: if we artificially raise the variability of torque control signals to match that of EMG, do subjects make similar errors and have similar uncertainty about their movements? We answered this question using two experiments in which subjects used three different control signals: torque, torque+noise, and EMG. First, we measured error on a simple target-hitting task in which subjects received visual feedback only at the end of their movements. We found that even when the signal-to-noise ratio was equal across EMG and torque+noise control signals, EMG resulted in larger errors. Second, we quantified uncertainty by measuring the just-noticeable difference of a visual perturbation. We found that for equal errors, EMG resulted in higher movement uncertainty than both torque and torque+noise. The differences suggest that performance and confidence are influenced by more than just the noisiness of the control signal, and suggest that other factors, such as the user's ability to incorporate feedback and develop accurate internal models, also have significant impacts on the performance and confidence of a person's actions. We theorize that users have difficulty distinguishing between random and systematic errors for EMG control, and future work should examine in more detail the types of errors made with EMG control.

Usefulness of the Montreal Cognitive Assessment (MoCA) in Huntington's disease.

PubMed

Gluhm, Shea; Goldstein, Jody; Brown, Daniel; Van Liew, Charles; Gilbert, Paul E; Corey-Bloom, Jody

2013-10-01

The Montreal Cognitive Assessment (MoCA) is a brief screening instrument for dementia that is sensitive to executive dysfunction. This study examined its usefulness for assessing cognitive performance in mild, moderate, and severe Huntington's disease (HD), compared with the use of the Mini-Mental State Examination (MMSE). We compared MoCA and MMSE total scores and the number of correct answers in 5 cognitive-specific domains in 104 manifest HD patients and 100 matched controls. For the total HD sample, and for the moderate and severe patients, significant differences between both MoCA and MMSE total scores and almost all cognitive-specific domains emerged. Even mild HD subjects showed significant differences with regard to total score and several cognitive domains on both instruments. We conclude that the MoCA, although not necessarily superior to the MMSE, is a useful instrument for assessing cognitive performance over a broad level of functioning in HD. © 2013 Movement Disorder Society.

Equalization and detection for digital communication over nonlinear bandlimited satellite communication channels. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Gutierrez, Alberto, Jr.

1995-01-01

This dissertation evaluates receiver-based methods for mitigating the effects due to nonlinear bandlimited signal distortion present in high data rate satellite channels. The effects of the nonlinear bandlimited distortion is illustrated for digitally modulated signals. A lucid development of the low-pass Volterra discrete time model for a nonlinear communication channel is presented. In addition, finite-state machine models are explicitly developed for a nonlinear bandlimited satellite channel. A nonlinear fixed equalizer based on Volterra series has previously been studied for compensation of noiseless signal distortion due to a nonlinear satellite channel. This dissertation studies adaptive Volterra equalizers on a downlink-limited nonlinear bandlimited satellite channel. We employ as figure of merits performance in the mean-square error and probability of error senses. In addition, a receiver consisting of a fractionally-spaced equalizer (FSE) followed by a Volterra equalizer (FSE-Volterra) is found to give improvement beyond that gained by the Volterra equalizer. Significant probability of error performance improvement is found for multilevel modulation schemes. Also, it is found that probability of error improvement is more significant for modulation schemes, constant amplitude and multilevel, which require higher signal to noise ratios (i.e., higher modulation orders) for reliable operation. The maximum likelihood sequence detection (MLSD) receiver for a nonlinear satellite channel, a bank of matched filters followed by a Viterbi detector, serves as a probability of error lower bound for the Volterra and FSE-Volterra equalizers. However, this receiver has not been evaluated for a specific satellite channel. In this work, an MLSD receiver is evaluated for a specific downlink-limited satellite channel. Because of the bank of matched filters, the MLSD receiver may be high in complexity. Consequently, the probability of error performance of a more practical suboptimal MLSD receiver, requiring only a single receive filter, is evaluated.

Normative data for the Tygerberg Cognitive Battery and Mini-Mental Status Examination in a South African population.

PubMed

Roos, Annerine; Calata, Dorothy; Jonkers, Liesl; Maritz, Stephan J; Kidd, Martin; Daniels, Willie M U; Hugo, Frans J

2010-01-01

Normative data for the Tygerberg Cognitive Battery (TCB) and Mini-Mental Status Examination (MMSE) (in South Africa) have not been formally examined before. The TCB was developed for the bedside pen-and-paper screening of cognitive impairment in each of the 6 main cognitive domains, including attention and concentration, speech, memory, praxis, gnosis, and executive functioning. The test is also used to diagnose different neuropsychiatric conditions. The MMSE is an established screen of cognitive status, which is often used as a comparative standard for novel screening tests such as the TCB. The TCB was initially developed in English and Afrikaans, and a Xhosa version was also initiated with this study so that the 3 most common languages of the region could be accommodated. The first aim of the study was to estimate normative test performance on the TCB and MMSE among controls, and the second aim was to develop a Xhosa version of the TCB. Assessments of the TCB and MMSE were carried out in a population of healthy individuals (n = 157). In addition, healthy Xhosa-speaking participants (n = 14) were screened using a Xhosa version of the TCB. Reliability scores for all forms of the TCB were satisfactory. Age and education correlated significantly with TCB scores (r = -0.26, P < .01; r = 0.64, P < .01, respectively), whereas only education significantly correlated with MMSE scores (r = 0.32, P < .05). Normative values were calculated accordingly, that is, controlled for the effects of age and education. The TCB scores also correlated significantly with MMSE scores (r = 0.49, P < .05), demonstrating the potential of the TCB to serve as an alternate cognitive assessment tool, along with the MMSE, to focus neuropsychiatric investigations. Scores on the Xhosa version differed significantly on speech, praxis, and gnosis between the Afrikaans and English participant scores. These normative data can be used to increase precision and to provide an impartial evaluation when applying TCB to evaluate the cognitive ability of neuropsychiatrically impaired adult patients. However, age and education effects should be considered when computing the results of cognitive assessment. Copyright 2010 Elsevier Inc. All rights reserved.

Glucose impairment and ghrelin gene variants are associated to cognitive dysfunction.

PubMed

Mora, M; Mansego, M L; Serra-Prat, M; Palomera, E; Boquet, X; Chaves, J F; Puig-Domingo, M

2014-04-01

Cognitive state and brain volume have been related to body mass index, abdominal fat, waist-hip ratio, components of metabolic syndrome (MS) and ghrelin. Genetic variations within the ghrelin gene have been recently associated to MS. The aim of our study was to investigate cognitive state by Mini-Mental State Examination (MMSE) in relation to MS components (ATP-III criteria) and ghrelin gene polymorphisms in dwelling individuals aged ≥70. 280 subjects (137 men/143 women, age 77.03 ± 5.92) from the Mataró Ageing Study were included. Individuals were phenotypically characterized by anthropometric variables, lipids, glucose, blood pressure and MMSE. SNPs -501AC (rs26802), -994CT (rs26312), -604GA (rs27647), M72L (rs696217) and L90G (rs4684677) of the ghrelin gene were studied. Genotypes were determined by polymerase chain reaction and SNapshot minisequencing. 22.1 % had MMSE <24. MMSE <24 was associated with age (p < 0.001), female gender (p = 0.016), low education (p < 0.001) and glucose impairment or diabetes (p = 0.040). MMSE was influenced by obesity, central obesity, MS and glucose impairment. This latter association remained significant after adjustment by gender, age, alcohol, educational level, GDS and ApoE genotype (p = 0.009). Ghrelin SNPs were associated to MMSE: M72L C/A genotype showed lower score than C/C (p = 0.032, after adjusting for confounders 0.049); L90G A/T genotype showed lower score than A/A (p = 0.054, after adjusting 0.005). MMSE <24 was associated to L90G (39.1 % in A/T genotype vs 19.3 % in A/A, p = 0.026, after adjusting for confounders p = 0.002, OR 6.18 CI 1.93-21.75). Glucose impairment and L90G Ghrelin gene variant influence cognitive function in old dwelling individuals participating in the Mataró Ageing Study.

Efficacy of acetylcholinesterase inhibitors versus nootropics in Alzheimer's disease: a retrospective, longitudinal study.

PubMed

Tsolaki, M; Pantazi, T; Kazis, A

2001-01-01

The aim of this study was to investigate the efficacy of nootropics (piracetam, aniracetam, nimodopine and dihydroergicristine) versus acetylcholinesterase inhibitors (AChE-Is) (tacrine and donepezil) in the treatment of Alzheimer's disease. This is a retrospective study of 510 patients with Alzheimer's disease. To determine clinical efficacy of treatment, we used the mean change over time in scores for the following tests: the Mini-Mental State Examination (MMSE); the Cambridge Cognitive Examination for the Elderly; and the Functional Rating Scale for Symptoms of Dementia. In all patients and in patients with severe Alzheimer's disease (baseline MMSE < 11), no significant differences were seen in the neuropsychological test scores between the two treatment groups. In patients with moderate dementia (baseline MMSE between 11 and 20), however, there was a significantly greater deterioration, as shown on the CAMCOG scale, after 12 months' treatment for patients receiving AChE-Is compared with those receiving nootropics (-4.38 for AChE-Is group versus 1.48 for nootropics group). For patients with mild dementia (baseline MMSE score between 21 and 26), there was a significantly greater deterioration on the MMSE scale for each time-point in the nootropics group compared with the AChE-Is group. In conclusion, we did not find any strong evidence that a difference in efficacy exists between AChE-Is and nootropics in the treatment of Alzheimer's disease.

Cognitive Function in Ambulatory Patients with Systolic Heart Failure: Insights from the Warfarin versus Aspirin in Reduced Cardiac Ejection Fraction (WARCEF) Trial

PubMed Central

Graham, Susan; Ye, Siqin; Qian, Min; Sanford, Alexandra R.; Di Tullio, Marco R.; Sacco, Ralph L.; Mann, Douglas L.; Levin, Bruce; Pullicino, Patrick M.; Freudenberger, Ronald S.; Teerlink, John R.; Mohr, J. P.; Labovitz, Arthur J.; Lip, Gregory Y. H.; Estol, Conrado J.; Lok, Dirk J.; Ponikowski, Piotr; Anker, Stefan D.; Thompson, John L. P.; Homma, Shunichi

2014-01-01

We sought to determine whether cognitive function in stable outpatients with heart failure (HF) is affected by HF severity. A retrospective, cross-sectional analysis was performed using data from 2, 043 outpatients with systolic HF and without prior stroke enrolled in the Warfarin versus Aspirin in Reduced Cardiac Ejection Fraction (WARCEF) Trial. Multivariable regression analysis was used to assess the relationship between cognitive function measured using the Mini-Mental Status Exam (MMSE) and markers of HF severity (left ventricular ejection fraction [LVEF], New York Heart Association [NYHA] functional class, and 6-minute walk distance). The mean (SD) for the MMSE was 28.6 (2.0), with 64 (3.1%) of the 2,043 patients meeting the cut-off of MMSE <24 that indicates need for further evaluation of cognitive impairment. After adjustment for demographic and clinical covariates, 6-minute walk distance (β-coefficient 0.002, p<0.0001), but not LVEF or NYHA functional class, was independently associated with the MMSE as a continuous measure. Age, education, smoking status, body mass index, and hemoglobin level were also independently associated with the MMSE. In conclusion, six-minute walk distance, but not LVEF or NYHA functional class, was an important predictor of cognitive function in ambulatory patients with systolic heart failure. PMID:25426862

Psychometric Properties of the Folstein Mini-Mental State Examination

ERIC Educational Resources Information Center

Lopez, Michael N.; Charter, Richard A.; Mostafavi, Beeta; Nibut, Lorraine P.; Smith, Whitney E.

2005-01-01

Criterion-referenced (Livingston) and norm-referenced (Gilmer-Feldt) techniques were used to measure the internal consistency reliability of Folsteins Mini-Mental State Examination (MMSE) on a large sample (N = 418) of elderly medical patients. Two administration and scoring variants of the MMSE Attention and Calculation section (Serial 7s only…

Adaptively combined FIR and functional link artificial neural network equalizer for nonlinear communication channel.

PubMed

Zhao, Haiquan; Zhang, Jiashu

2009-04-01

This paper proposes a novel computational efficient adaptive nonlinear equalizer based on combination of finite impulse response (FIR) filter and functional link artificial neural network (CFFLANN) to compensate linear and nonlinear distortions in nonlinear communication channel. This convex nonlinear combination results in improving the speed while retaining the lower steady-state error. In addition, since the CFFLANN needs not the hidden layers, which exist in conventional neural-network-based equalizers, it exhibits a simpler structure than the traditional neural networks (NNs) and can require less computational burden during the training mode. Moreover, appropriate adaptation algorithm for the proposed equalizer is derived by the modified least mean square (MLMS). Results obtained from the simulations clearly show that the proposed equalizer using the MLMS algorithm can availably eliminate various intensity linear and nonlinear distortions, and be provided with better anti-jamming performance. Furthermore, comparisons of the mean squared error (MSE), the bit error rate (BER), and the effect of eigenvalue ratio (EVR) of input correlation matrix are presented.

Predictors of Performance on the MMSE and the DRS-2 Among American Indian Elders

PubMed Central

Jervis, Lori L.; Fickenscher, Alexandra; Beals, Janette; Cullum, C. Munro; Novins, Douglas K.; Manson, Spero M.; Arciniegas, David B.

2015-01-01

Little is known about factors that predict older American Indians’ performance on cognitive tests. This study examined 137 American Indian elders’ performance on the MMSE and the Dementia Rating Scale—Second Edition (DRS-2). Multivariate regression identified younger age, more education, not receiving Supplemental Security Income, and frequent receipt of needed health care as predictors of better performance on the MMSE. Better performance on the DRS-2 was predicted by more education, boarding school attendance, not receiving Supplemental Security Income, and frequent receipt of needed health care. This study points to the importance of economic and educational factors on cognitive test performance among American Indian elders. PMID:21037127

Predictors of performance on the MMSE and the DRS-2 among American Indian elders.

PubMed

Jervis, Lori L; Fickenscher, Alexandra; Beals, Janette; Cullum, C Munro; Novins, Douglas K; Manson, Spero M; Arciniegas, David B

2010-01-01

Little is known about factors that predict older American Indians' performance on cognitive tests. This study examined 137 American Indian elders' performance on the MMSE and the Dementia Rating Scale-Second Edition (DRS-2). Multivariate regression identified younger age, more education, not receiving Supplemental Security Income, and frequent receipt of needed health care as predictors of better performance on the MMSE. Better performance on the DRS-2 was predicted by more education, boarding school attendance, not receiving Supplemental Security Income, and frequent receipt of needed health care. This study points to the importance of economic and educational factors on cognitive test performance among American Indian elders.

Variables Associated with Cognitive Function in Elderly California Seventh-day Adventists

PubMed Central

Fraser, Gary E.; Singh, Pramil N.; Bennett, Hannelore

2012-01-01

From a cohort of white, non-Hispanic California Seventh-day Adventists, 99 subjects over age 75 years in 1991 were randomly selected. Dietary habits and educational status had been measured in 1976. Subjects completed the Mini-Mental State Examination (MMSE) in 1991, and at that time, they or caregivers also gave information on current medical problems and drug therapy. Those who ate more calories in 1976 had lower MMSE scores in 1991 (p = 0.03), an association strengthened by excluding those with previous stroke or Parkinson’s disease by 1991. This raises the possibility that higher consumption of calories in middle age may accelerate the decline in cognitive function seen with aging, as apparently occurs in some animals. Less-educated subjects had lower MMSE scores, especially among the very elderly. The statistical model predicts that the negative association between use of psychotropic drugs and MMSE score (p = 0.004) is particularly potent in those cognitively impaired for other reasons. If causal, this suggests that physicians should use these agents very cautiously in such subjects. PMID:8651216

Variables associated with cognitive function in elderly California Seventh-day Adventists.

PubMed

Fraser, G E; Singh, P N; Bennett, H

1996-06-15

From a cohort of white, non-Hispanic California Seventh-day Adventists, 99 subjects over age 75 years in 1991 were randomly selected. Dietary habits and educational status had been measured in 1976. Subjects completed the Mini-Mental State Examination (MMSE) in 1991, and at that time, they or caregivers also gave information on current medical problems and drug therapy. Those who ate more calories in 1976 had lower MMSE scores in 1991 (p = 0.03), an association strengthened by excluding those with previous stroke or Parkinson's disease by 1991. This raises the possibility that higher consumption of calories in middle age may accelerate the decline in cognitive function seen with aging, as apparently occurs in some animals. Less-educated subjects had lower MMSE scores, especially among the very elderly. The statistical model predicts that the negative association between use of psychotropic drugs and MMSE score (p = 0.004) is particularly potent in those cognitively impaired for other reasons. If causal, this suggests that physicians should use these agents very cautiously in such subjects.

The mini mental state examination at the time of Alzheimer's disease and related disorders diagnosis, according to age, education, gender and place of residence: a cross-sectional study among the French National Alzheimer database.

PubMed

Pradier, Christian; Sakarovitch, Charlotte; Le Duff, Franck; Layese, Richard; Metelkina, Asya; Anthony, Sabine; Tifratene, Karim; Robert, Philippe

2014-01-01

was firstly to describe the MMSE (Mini-Mental State Examination) score upon initial diagnosis of Alzheimer's disease and related disorders among the French population, according to age. Secondly, education, gender and place of residence were studied as factors potentially associated with delayed Alzheimer's disease diagnosis. we conducted a cross sectional analysis of the French National Alzheimer database (BNA). Data from 2008 to 2012 were extracted. Patients were selected at the moment of their first diagnosis of AD (n = 39,451). The MMSE score at initial diagnosis dropped significantly with increasing age. The test score increased with the degree of educational background regardless of age. Gender and place of residence were significantly related to the MMSE score, women and persons living in medical institutions having lower MMSE scores under the age of 90 years and at all educational levels. Health care professionals should be aware of these risk factors in order to maximize chances of earliest possible diagnosis of Alzheimer's disease and related disorders.

Influence of mental practice and movement observation on motor memory, cognitive function and motor performance in the elderly

PubMed Central

Altermann, Caroline D. C.; Martins, Alexandre S.; Carpes, Felipe P.; Mello-Carpes, Pâmela B.

2014-01-01

Background With aging, it is important to maintain cognitive and motor functions to ensure autonomy and quality of life. During the acquisition of motor skills, it is necessary for the elderly to understand the purpose of the proposed activities. Physical and mental practice, as well as demonstrations, are strategies used to learn movements. Objectives To investigate the influence of mental practice and the observation of movement on motor memory and to understand the relationship between cognitive function and motor performance in the execution of a sequence of digital movements in the elderly. Method This was a cross-sectional study conducted with 45 young and 45 aged subjects. The instruments used were Mini-Mental State Examination (MMSE), Manual Preference Inventory and a Digital Motor Task (composed of a training of a sequence of movements, an interval and a test phase). The subjects were divided into three subgroups: control, mental practice and observation of movement. Results The elderly depend more strongly on mental practice for the acquisition of a motor memory. In comparing the performances of people in different age groups, we found that in the elderly, there was a negative correlation between the MMSE score and the execution time as well as the number of errors in the motor task. Conclusions For the elderly, mental practice can advantage motor performance. Also, there is a significant relationship between cognitive function, learning and the execution of new motor skills. PMID:24839046

Effects of education on very mild dementia among Chinese people in Hong Kong: potential mediators in the Cantonese Mini-Mental State Examination tasks.

PubMed

Tse, C S; Chang, J F; Leung, Grace T Y; Fung, Ada W T; Hau, K T; Chiu, Helen F K; Lam, Linda C W

2013-01-01

In Hong Kong, older Chinese adults generally have a low level of education. This study examined the effect of education on very mild Alzheimer's disease (AD), as quantified by Clinical Dementia Rating (CDR) scale (CDR 0.5 versus 0), in a Chinese community. The Cantonese version of the Mini-Mental State Examination (C-MMSE) was used to estimate cognitive abilities that were related to the level of education, and that in turn serve as protective factors for AD. A total of 788 community-dwelling older adults (383 CDR 0 and 405 CDR 0.5) were recruited in this cross-sectional study, which was derived from a population-based prevalence project. The participants' number of years of education and C-MMSE scores were used to predict their CDR scores using logistic regression and the mediation effects of C-MMSE scores were analyzed. Consistent with previous studies, the chance of being rated as having very mild AD increased with age, but decreased with years of education, among the older adult community of Hong Kong. The effect of education on very mild dementia was weakened substantially when C-MMSE scores were included as mediating variables. The findings indicate that the protective effects of education on dementia were mediated by an enhancement of older adults' performance on some C-MMSE items, including attention and orientation to time and place.

Exposure to smoking in movies and smoking initiation among black youth.

PubMed

Dal Cin, Sonya; Stoolmiller, Mike; Sargent, James D

2013-04-01

Black adolescents see more substance use in mainstream media but seem less responsive to it than other U.S. adolescents. Black-oriented media may be more personally relevant to them. To determine smoking exposure separately for black-oriented (BSME) and mainstream (MMSE) movies and assess their longitudinal relationships with smoking among black and other-race adolescents. Two-wave (2007-2009) national cohort survey of 2341 nonsmoking (at baseline) U.S. adolescents (aged 13-19 years), analyzed in 2012. The surveys determined BMSE and MMSE based on respondents' exposure to random subsets of 50 movies from a contemporary sample of 95 black-oriented and 288 mainstream movies previously content-coded for smoking. Outcome was smoking initiation. Black teens had significantly more BMSE and MMSE than other teens (p's <0.001). At follow-up, 23.5% of black and 29.0% of nonblack respondents had tried smoking. Among black respondents, BMSE was related to smoking initiation at follow-up but MMSE was not. For other adolescents, both BMSE and MMSE were related to smoking initiation. A prospective relationship was found between exposure to smoking in movies and smoking initiation. Among black adolescents in the U.S., this was only for black-oriented movies, suggesting the importance of personal relevance of the exposures. Parents, practitioners, and producers should be aware of these potential influences of media on black teen viewers. Copyright © 2013 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Cross-cultural comparisons of the Mini-mental State Examination between Japanese and U.S. cohorts

PubMed Central

Meguro, Kenichi; Ishii, Hiroshi; Yamaguchi, Satoshi; Saxton, Judith A.; Ganguli, Mary

2009-01-01

Background The Mini-mental State Examination (MMSE) is widely used in Japan and the U.S.A. for cognitive screening in the clinical setting and in epidemiological studies. A previous Japanese community study reported distributions of the MMSE total score very similar to that of the U.S.A. Methods Data were obtained from the Monongahela Valley Independent Elder's Study (MoVIES), a representative sample of community-dwelling elderly people aged 65 and older living near Pittsburgh, U.S.A., and from the Tajiri Project, with similar aims in Tajiri, Japan. We examined item-by-item distributions of the MMSE between two cohorts, comparing (1) percentage of correct answers for each item within each cohort, and (2) relative difficulty of each item measured by Item Characteristic Curve analysis (ICC), which estimates log odds of obtaining a correct answer adjusted for the remaining MMSE items, demographic variables (age, gender, education) and interactions of demographic variables and cohort. Results Median MMSE scores were very similar between the two samples within the same education groups. However, the relative difficulty of each item differed substantially between the two cohorts. Specifically, recall and auditory comprehension were easier for the Tajiri group, but reading comprehension and sentence construction were easier for the MoVIES group. Conclusions Our results reaffirm the importance of validation and examination of thresholds in each cohort to be studied when a common instrument is used as a dementia screening tool or for defining cognitive impairment. PMID:18925977

Utility of TICS-M for the assessment of cognitive function in older adults.

PubMed

de Jager, Celeste A; Budge, Marc M; Clarke, Robert

2003-04-01

Routine screening of high-risk elderly people for early cognitive impairment is constrained by the limitations of currently available cognitive function tests. The Telephone Interview of Cognitive Status is a novel instrument for assessment of cognitive function that can be administered in person or by telephone. To evaluate the determinants and utility of TICS-M (13-item modified version) for assessment of cognitive function in healthy elderly people. The utility of TICS-M was compared with more widely used MMSE and CAMCOG in a cross-sectional survey of 120 older (62 to 89 years) UK adults. The TICS-M cognitive test scores (27.97, SD 4.15) were normally distributed in contrast with those for MMSE and CAMCOG that had a negatively skewed distribution. TICS-M scores were inversely correlated with age (r = -0.21) and with the NART fullscale IQ (r = -0.35), but were independent of years of education in this cohort. TICS-M was highly correlated with MMSE (r = 0.57) and with CAMCOG (r = 0.62) scores. The time required to complete the test is comparable to MMSE and substantially less than CAMCOG. The normal distribution of TICS-M test scores suggest that this test is less constrained by the ceiling effect which limits the utility of MMSE and CAMCOG test scores in detecting early cognitive impairment. TICS-M is an appropriate instrument to assess cognitive function in both research and in clinical practice. Copyright 2003 John Wiley & Sons, Ltd.

Albumin, Hemoglobin, and the Trajectory of Cognitive Function in Community-Dwelling Older Japanese: A 13-Year Longitudinal Study.

PubMed

Murayama, H; Shinkai, S; Nishi, M; Taniguchi, Y; Amano, H; Seino, S; Yokoyama, Y; Yoshida, H; Fujiwara, Y; Ito, H

2017-01-01

Cognitive function can substantially decline over a long period, and understanding the trajectory of cognitive function is important. However, little is known about the linkage between nutritional biomarkers and long-term cognitive change. We analyzed 13-year longitudinal data for older Japanese to examine the associations of serum albumin and hemoglobin levels with the trajectory of cognitive function. Longitudinal study. Community-based. A total of 1,744 community-dwelling adults aged 65 years or older who participated in annual health examinations in Kusatsu town, Gunma Prefecture, Japan, from 2002-2014. Cognitive function was assessed annually by the Mini-Mental State Examination (MMSE). Albumin and hemoglobin levels at baseline (the year when a respondent first participated in the health examination) were divided into quartiles. Hierarchical linear modeling was used to analyze intrapersonal and interpersonal differences in cognitive function. Participants' MMSE scores decreased at an accelerated rate over the 13-year period. Participants with the lowest baseline albumin level (below the first quartile line) showed a greater accelerated decline in MMSE scores over time, compared with those with the highest level (above the third quartile line). Moreover, MMSE scores in participants with a lower hemoglobin level and lower MMSE score at baseline tended to decline faster over time at an accelerated rate. These findings yield new insights about the complex and diverse roles of these nutritional biomarkers on the trajectory of cognitive function in old age.

Tracking Cognitive Decline in Amnestic Mild Cognitive Impairment and Early-Stage Alzheimer Dementia: Mini-Mental State Examination versus Neuropsychological Battery.

PubMed

Kim, Joonho; Na, Han Kyu; Byun, Justin; Shin, Jiwon; Kim, Sungsoo; Lee, Byung Hwa; Na, Duk L

2017-01-01

Although the Mini-Mental State Examination (MMSE), Clinical Dementia Rating-Sum of Boxes (CDR-SOB), and neuropsychological batteries are widely used for evaluating cognitive function, it remains elusive which instrument best reflects the longitudinal disease progression in amnestic mild cognitive impairment (aMCI) and probable Alzheimer disease (AD). We investigated whether changes in these three instruments over time correlate with loss of cortical gray matter volume (cGMV). We retrospectively investigated 204 patients (aMCI, n = 114; AD, n = 90) who had undergone MMSE, CDR-SOB, the dementia version of the Seoul Neuropsychological Screening Battery (SNSB-D), and 3-dimensional T1-weighted magnetic resonance images at least twice. We investigated the partial correlation between annual decline in test scores and percent change of cGMV. In aMCI patients, changes in the SNSB-D total score (r = 0.340, p < 0.001) and CDR-SOB (r = 0.222, p = 0.020), but not MMSE, showed a correlation with cGMV loss, with the SNSB-D total score showing the strongest correlation. In AD patients, decline in all three test scores correlated significantly with cGMV loss, with MMSE exhibiting the strongest correlation (r = 0.464, p < 0.001). In aMCI patients, neuropsychological battery, though time-consuming, was the most adequate tool in tracking disease progression. In AD patients, however, MMSE may be the most effective longitudinal monitoring tool when considering cost-effectiveness. © 2017 S. Karger AG, Basel.

Exposure to Smoking in Movies and Smoking Initiation Among Black Youth

PubMed Central

Dal Cin, Sonya; Stoolmiller, Mike; Sargent, James D.

2013-01-01

Background Black adolescents see more substance use in mainstream media but seem less responsive to it than other U.S. adolescents. Black-oriented media may be more personally relevant to them. Purpose To determine smoking exposure separately for black-oriented (BSME) and mainstream (MMSE) movies and assess their longitudinal relationships with smoking among black and other-race adolescents. Methods Two-wave (2007–2009) national cohort survey of 2341 nonsmoking (at baseline) U.S. adolescents (aged 13–19 years), analyzed in 2012. The surveys determined BMSE and MMSE based on respondents’ exposure to random subsets of 50 movies from a contemporary sample of 95 black-oriented and 288 mainstream movies previously content-coded for smoking. Outcome was smoking initiation. Results Black teens had significantly more BMSE and MMSE than other teens (p’s <0.001). At follow-up, 23.5% of black and 29.0% of nonblack respondents had tried smoking. Among black respondents, BMSE was related to smoking initiation at follow-up but MMSE was not. For other adolescents, both BMSE and MMSE were related to smoking initiation. Conclusions A prospective relationship was found between exposure to smoking in movies and smoking initiation. Among black adolescents in the U.S., this was only for black-oriented movies, suggesting the importance of personal relevance of the exposures. Parents, practitioners, and producers should be aware of these potential influences of media on black teen viewers. PMID:23498099

Assessment of cognitive impairment in long-term oxygen therapy-dependent COPD patients.

PubMed

Karamanli, Harun; Ilik, Faik; Kayhan, Fatih; Pazarli, Ahmet Cemal

2015-01-01

A number of studies have shown that COPD, particularly in its later and more severe stages, is associated with various cognitive deficits. Thus, the primary goal of the present study was to elucidate the extent of cognitive impairment in patients with long-term oxygen therapy-dependent (LTOTD) COPD. In addition, this study aimed to determine the effectiveness of two cognitive screening tests, the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA), for COPD patients and the ability of oxygen therapy to mitigate COPD-related deficits in cognitive function. The present study enrolled 45 subjects: 24 nonuser and 21 regular-user LTOTD-COPD patients. All subjects had a similar grade of education, and there were no significant differences regarding age or sex. The MoCA (cutoff: <26 points) and MMSE (cutoff: ≤24 points) scores were compared between these two groups. The nonuser LTOTD-COPD group had a significantly lower MoCA score than that of the regular-user LTOTD-COPD group (19.38±2.99 vs 21.68±2.14, respectively) as well as a significantly lower MMSE score. Moreover, the absence of supplemental oxygen therapy increased the risk of cognitive impairment (MoCA, P=0.007 and MMSE, P=0.014), and the MoCA and MMSE scores significantly correlated with the number of emergency admissions and the number of hospitalizations in the last year. In the present study, the nonuser LTOTD-COPD group exhibited a significant decrease in cognitive status compared with the regular-user LTOTD-COPD group. This suggests that the assessment of cognitive function in nonuser LTOTD-COPD patients and the use of protective strategies, such as continuous supplemental oxygen treatment, should be considered during the management of COPD in this population. In addition, the MoCA score was superior to the MMSE score for the determination of cognitive impairment in the nonuser LTOTD-COPD patients.

A Pilot Study: The Beneficial Effects of Combined Statin-exercise Therapy on Cognitive Function in Patients with Coronary Artery Disease and Mild Cognitive Decline.

PubMed

Toyama, Kensuke; Sugiyama, Seigo; Oka, Hideki; Hamada, Mari; Iwasaki, Yuri; Horio, Eiji; Rokutanda, Taku; Nakamura, Shinichi; Spin, Joshua M; Tsao, Philip S; Ogawa, Hisao

2017-01-01

Objective Hypercholesterolemia, a risk factor in cognitive impairment, can be treated with statins. However, cognitive decline associated with "statins" (HMG-CoA reductase inhibitors) is a clinical concern. This pilot study investigated the effects of combining statins and regular exercise on cognitive function in coronary artery disease (CAD) patients with prior mild cognitive decline. Methods We recruited 43 consecutive CAD patients with mild cognitive decline. These patients were treated with a statin and weekly in-hospital aerobic exercise for 5 months. We measured serum lipids, exercise capacity, and cognitive function using the mini mental state examination (MMSE). Results Low-density lipoprotein cholesterol levels were significantly decreased, and maximum exercise capacity (workload) was significantly increased in patients with CAD and mild cognitive decline after treatment compared with before. Combined statin-exercise therapy significantly increased the median (range) MMSE score from 24 (22-25) to 25 (23-27) across the cohort (p<0.01). Changes in body mass index (BMI) were significantly and negatively correlated with changes in the MMSE. After treatment, MMSE scores in the subgroup of patients that showed a decrease in BMI were significantly improved, but not in the BMI-increased subgroup. Furthermore, the patients already on a statin at the beginning of the trial displayed a more significant improvement in MMSE score than statin-naïve patients, implying that exercise might be the beneficial aspect of this intervention as regards cognition. In a multivariate logistic regression analysis adjusted for age >65 years, sex, and presence of diabetes mellitus, a decrease in BMI during statin-exercise therapy was significantly correlated with an increase in the MMSE score (odds ratio: 4.57, 95% confidence interval: 1.05-20.0; p<0.05). Conclusion Statin-exercise therapy may help improve cognitive dysfunction in patients with CAD and pre-existing mild cognitive decline.

How Can We Best Screen for Cognitive Impairment in Malaysia? A Pilot of the IDEA Cognitive Screen and Picture-Based Memory Impairment Scale and Comparison of Criterion Validity with the Mini Mental State Examination.

PubMed

Rosli, Roshaslina; Tan, Maw Pin; Gray, William K; Subramanian, Pathmawathi; Mohd Hairi, Noran Naqiah; Chin, Ai-Vyrn

2017-01-01

To pilot two new cognitive screening tools for use in an urban Malaysian population and to compare their criterion validity against a gold standard, the well-established Mini-Mental State Examination (MMSE). The IDEA cognitive screen, Picture-based Memory Impairment Scale (PMIS), and MMSE were administered to a convenience sample of elderly (≥ 65 years) from the community and outpatient clinics at an urban teaching hospital. Consensus diagnosis was performed by two geriatricians blinded to PMIS and IDEA cognitive screen scores using the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-V) clinical criteria. The MMSE performance was used as a reference. The study enrolled 66 participants, with a median age of 78.5 years (interquartile range [IQR], 72.5-83.0) years and 11.0 median years of education (IQR, 9.0-13.0). Forty-three (65.2%) were female, and 32 (48.4%) were Chinese. The area under the receiver operating characteristic (AUROC) curve values were .962 (IDEA cognitive screen), .970 (PMIS), and .935 (MMSE). The optimal cutoff values for sensitivity and specificity were: IDEA cognitive screen: ≤ 11, 90.9% and 89.7%; PMIS: ≤ 6, 97.3% and 69.0%; and MMSE: ≤ 23, 84.6% and 76.0%. Although the sample size was small, multivariable logistic regression modelling suggested that all three screen scores did not appear to be educationally biased. The IDEA and PMIS tools are potentially valid screening tools for dementia in urban Malaysia, and perform at least as well as the MMSE. Further work on larger representative, cohorts is needed to further assess the psychometric properties. Study provides alternative screening tools for dementia for both non-specialists and specialists.

Cognitive changes after parathyroidectomy in patients with secondary hyperparathyroidism.

PubMed

Chou, Fong-Fu; Chen, Jin-Bor; Hsieh, Kun-Chou; Liou, Chia-Wei

2008-04-01

Cognitive impairment was frequently reported in uremic patients with dialysis, but improvements of cognition after parathyroidectomy for symptomatic secondary hyperparathyroidism have never been reported before. Thirty-nine patients, who were successfully operated on with total parathyroidectomy plus autotransplantation were enrolled. Twenty-three dialysis patients, age >50 years, who had a serum level of intact parathyroid hormone (iPTH) greater than 650 pg/ml, and who did not undergo parathyroidectomy were selected as the control group. The mini-mental state examination (MMSE) and the clinical dementia rating (CDR) test were administered to all patients. Before the operation, educational level, symptoms of bone pain, skin itching, general weakness and insomnia were recorded and serum levels of calcium, phosphorus, alkaline phosphatase (Alk-ptase), iPTH, aluminum, and hemoglobin were measured in the study and control groups. At 12-week postoperatively, serum levels of calcium, phosphorus, Alk-ptase, iPTH, and aluminum were measured again and at 16-week postoperatively, the MMSE and the CDR test were administered again. In the control group, both MMSE and CDR test were administered again after the period or 16-week. Serum calcium level was only significant difference (p = 0.002), whereas clinical symptoms, gender, etiologies of secondary hyperparathyroidism, duration of dialysis, educational level, age, and serum levels of phosphorus, Alk-ptase, iPTH, aluminum, and hemoglobin were not significantly different between the two groups. The educational level was the only factor affecting MMSE scores (p = 0.003). In the study group, at 12-week postoperatively, symptoms improved significantly, serum levels of calcium, phosphorus, Alk-ptase, iPTH, and aluminum decreased significantly, and at 16-week postoperatively, MMSE scores increased from 25 +/- 5 (mean +/- SD) to 26 +/- 5 (p < 0.001) and CDR scales decreased significantly (p < 0.001). Neither MMSE scores nor CDR scales of the control group changed significantly after the 16-week period. Parathyroidectomy for symptomatic secondary hyperparathyroidism can improve cognition.

A joint equalization algorithm in high speed communication systems

NASA Astrophysics Data System (ADS)

Hao, Xin; Lin, Changxing; Wang, Zhaohui; Cheng, Binbin; Deng, Xianjin

2018-02-01

This paper presents a joint equalization algorithm in high speed communication systems. This algorithm takes the advantages of traditional equalization algorithms to use pre-equalization and post-equalization. The pre-equalization algorithm takes the advantage of CMA algorithm, which is not sensitive to the frequency offset. Pre-equalization is located before the carrier recovery loop in order to make the carrier recovery loop a better performance and overcome most of the frequency offset. The post-equalization takes the advantage of MMA algorithm in order to overcome the residual frequency offset. This paper analyzes the advantages and disadvantages of several equalization algorithms in the first place, and then simulates the proposed joint equalization algorithm in Matlab platform. The simulation results shows the constellation diagrams and the bit error rate curve, both these results show that the proposed joint equalization algorithm is better than the traditional algorithms. The residual frequency offset is shown directly in the constellation diagrams. When SNR is 14dB， the bit error rate of the simulated system with the proposed joint equalization algorithm is 103 times better than CMA algorithm, 77 times better than MMA equalization, and 9 times better than CMA-MMA equalization.

[Toward constructing a system for detecting and coping with senile dementia in early stages among community-dwelling older people].

PubMed

Fujiwara, Yoshinori; Amano, Hidenori; Mori, Setsuko; Watanabe, Shuichiro; Kumagai, Shu; Yoshida, Yuko; Kim, Jungnim; Takabayashi, Koji; Yoshida, Hiroto; Ishihara, Miyuki; Eguchi, Fusako; Fuse, Sumie; Morita, Masahiro; Nagai, Hiroko; Shinkai, Shoji

2003-08-01

To establish a community health care system for screening community-dwelling older people with mild cognitive decline (MCD) and early diagnosis by a medical specialist. Out of all the elderly residents aged 65 years and over living in Yoita town in 2000 (n = 1673), 1544 participated in the interview survey held at community halls or at home (92.3% response). They underwent a Mini-Mental State Examination (MMSE) for assessment of cognitive function and answered questionnaires covering socio-demographic, psychological, physical and medical, and social activity items (2000/11). We defined cognitive decline as an MMSE < or = 1 SD below the age-specific mean (n = 371). Out of a total eligible population of 332, 158 pairs of subjects and their proxies participated in a follow-up survey (2001/11). The subjects themselves underwent MMSE again, and were asked for complaints of memory-related problems. Proxies answered about functional capacity and memory-related problems of subjects, for which we assessed the level of dementia with the Clinical Dementia Rating (CDR). We established criteria for encouragement to undergo detailed examination by a medical specialist as follows. 1) MMSE scores < or = 1 SD below age-specific means at both baseline and follow-up surveys, or 2) CDR > or = 0.5, and 3) not due to mental retardation. Non-participants had significant higher MMSE scores but were younger in the follow-up survey. Out of 96 subjects eligible for the detailed examination, 47 participants showed a tendency for older age with lower MMSE scores or younger age with higher MMSE scores than the average in the follow-up survey. The detailed examinations confirmed dementia of Alzheimer's type in 22 and vascular dementia in 13 on DSM-IV or magnetic resonance imaging. During our screening, 8 community care saloons were opened and the number of facilities for older people with cognitive decline is increasing. To establish a community health care system to screen and cope with community-dwelling older people with MCD in earlier stages, increased awareness of residents with slight MCD is especially important. Our attempt also suggested the importance of educational lectures, methods for testing cognitive function, and dementia care activity.

Study of a co-designed decision feedback equalizer, deinterleaver, and decoder

NASA Technical Reports Server (NTRS)

Peile, Robert E.; Welch, Loyd

1990-01-01

A technique that promises better quality data from band limited channels at lower received power in digital transmission systems is presented. Data transmission, in such systems often suffers from intersymbol interference (ISI) and noise. Two separate techniques, channel coding and equalization, have caused considerable advances in the state of communication systems and both concern themselves with removing the undesired effects of a communication channel. Equalizers mitigate the ISI whereas coding schemes are used to incorporate error-correction. In the past, most of the research in these two areas has been carried out separately. However, the individual techniques have strengths and weaknesses that are complementary in many applications: an integrated approach realizes gains in excess to that of a simple juxtaposition. Coding schemes have been successfully used in cascade with linear equalizers which in the absence of ISI provide excellent performance. However, when both ISI and the noise level are relatively high, nonlinear receivers like the decision feedback equalizer (DFE) perform better. The DFE has its drawbacks: it suffers from error propagation. The technique presented here takes advantage of interleaving to integrate the two approaches so that the error propagation in DFE can be reduced with the help of error correction provided by the decoder. The results of simulations carried out for both, binary, and non-binary, channels confirm that significant gain can be obtained by codesigning equalizer and decoder. Although, systems with time-invariant channels and simple DFE having linear filters were looked into, the technique is fairly general and can easily be modified for more sophisticated equalizers to obtain even larger gains.

Linear time-dependent reference intervals where there is measurement error in the time variable-a parametric approach.

PubMed

Gillard, Jonathan

2015-12-01

This article re-examines parametric methods for the calculation of time specific reference intervals where there is measurement error present in the time covariate. Previous published work has commonly been based on the standard ordinary least squares approach, weighted where appropriate. In fact, this is an incorrect method when there are measurement errors present, and in this article, we show that the use of this approach may, in certain cases, lead to referral patterns that may vary with different values of the covariate. Thus, it would not be the case that all patients are treated equally; some subjects would be more likely to be referred than others, hence violating the principle of equal treatment required by the International Federation for Clinical Chemistry. We show, by using measurement error models, that reference intervals are produced that satisfy the requirement for equal treatment for all subjects. © The Author(s) 2011.

Binarization of apodizers by adapted one-dimensional error diffusion method

NASA Astrophysics Data System (ADS)

Kowalczyk, Marek; Cichocki, Tomasz; Martinez-Corral, Manuel; Andres, Pedro

1994-10-01

Two novel algorithms for the binarization of continuous rotationally symmetric real positive pupil filters are presented. Both algorithms are based on 1-D error diffusion concept. The original gray-tone apodizer is substituted by a set of transparent and opaque concentric annular zones. Depending on the algorithm the resulting binary mask consists of either equal width or equal area zones. The diffractive behavior of binary filters is evaluated. It is shown that the pupils with equal width zones give Fraunhofer diffraction pattern more similar to that of the original continuous-tone pupil than those with equal area zones, assuming in both cases the same resolution limit of printing device.

Construct validation of two music-based assessments for people with dementia.

PubMed

Lipe, Anne W; York, Elizabeth; Jensen, Eric

2007-01-01

The purpose of this study was to substantiate the usefulness of the tasks on two music-based assessments in providing information about music cognition among people with dementia and to more fully understand the nature of this construct and its relationship to general cognition. Individuals with dementia (N = 50) received 3 evaluations: the Mini-Mental State Exam (MMSE), the MBECF, and the RMST. Results of the study revealed significant correlations between the MMSE and both music-based assessments. A pattern of correlations between the MMSE and the subsets of tasks contained in both music-based assessments showed that while there are strong relationships between music and general cognition, that there also is uniqueness to the melodic, singing and rhythmic aspects of music cognition.

Multiple point least squares equalization in a room

NASA Technical Reports Server (NTRS)

Elliott, S. J.; Nelson, P. A.

1988-01-01

Equalization filters designed to minimize the mean square error between a delayed version of the original electrical signal and the equalized response at a point in a room have previously been investigated. In general, such a strategy degrades the response at positions in a room away from the equalization point. A method is presented for designing an equalization filter by adjusting the filter coefficients to minimize the sum of the squares of the errors between the equalized responses at multiple points in the room and delayed versions of the original, electrical signal. Such an equalization filter can give a more uniform frequency response over a greater volume of the enclosure than can the single point equalizer above. Computer simulation results are presented of equalizing the frequency responses from a loudspeaker to various typical ear positions, in a room with dimensions and acoustic damping typical of a car interior, using the two approaches outlined above. Adaptive filter algorithms, which can automatically adjust the coefficients of a digital equalization filter to achieve this minimization, will also be discussed.

Effect of twist on single-mode fiber-optic 3 × 3 couplers

NASA Astrophysics Data System (ADS)

Chen, Dandan; Ji, Minning; Peng, Lei

2018-01-01

In the fabricating process of a 3 × 3 fused tapered coupler, the three fibers are usually twisted to be close-contact. The effect of twist on 3 × 3 fused tapered couplers is investigated in this paper. It is found that though a linear 3 × 3 coupler may realize equal power splitting ratio theoretically by twisting a special angle, it is hard to be fabricated actually because the twist angle and the coupler's length must be determined in advance. While an equilateral 3 × 3 coupler can not only realize approximate equal power splitting ratio theoretically but can also be fabricated just by controlling the elongation length. The effect of twist on the equilateral 3 × 3 coupler lies in the relationship between the equal ratio error and the twist angle. The more the twist angle is, the larger the equal ratio error may be. The twist angle usually should be no larger than 90° on one coupling period length in order to keep the equal ratio error small enough. The simulation results agree well with the experimental data.

[Revalidation and standardization of the cognition mini-exam (first Spanish version of the Mini-Mental Status Examination) in the general geriatric population].

PubMed

Lobo, A; Saz, P; Marcos, G; Día, J L; de la Cámara, C; Ventura, T; Morales Asín, F; Fernando Pascual, L; Montañés, J A; Aznar, S

1999-06-05

The revalidation of the Mini Examen Cognoscitivo (MEC), first Spanish version (1978) of the Mini-Mental Status Examination (MMSE) and documentation of "population-based norms" should clarify the potential confusion induced by later versions of MMSE. The Zaragoza Study on the prevalence of dementia and depression in a representative sample of the elderly community (N = 1,080). MEC-35 and MEC-30 points, and validated, Spanish versions of Geriatric Mental State (GMS), History and Aetiology Schedule (HAS) and Social Status Schedule (SSS). a) validation of MEC (standardized lay interviewers) against the gold standard of psychiatric diagnosis (DSM-III-R), two months later; b) "population-based norms" in the "healthy" population, and c) comparison with other MMSE versions. The instrument fulfills criteria of "feasibility", "content", "procedural" and "construct validity". Test-retest reliability: weighted kappa = 0.637. MEC-30 (cut-off point 23/24), sensitivity = 89.8%, specificity = 75.1% (80.8% with the cut-off at 22/23), and ROC curve, AUC = 0.920. The coefficients of individual items were satisfactory and the specificity increases in MEC-35 (83.9%). Other MMSE Spanish versions have not improved these coefficients. "Population-based norms" confirm the hypothesized influence of age and education level. MEC-30 is the version with most comparable results with the MMSE in USA. The validity of MEC is confirmed in the elderly population, with the same cut-off points recommended in the original standardization. MEC-30 is the best version for international comparisons.

Comparison of the montreal cognitive assessment and the mini-mental state examination as screening tests in hemodialysis patients without symptoms.

PubMed

Lee, Sun Hwa; Cho, AJin; Min, Yang-Ki; Lee, Young-Ki; Jung, San

2018-11-01

Cognitive impairment in end-stage renal disease patients is associated with an increased risk of mortality. We examined the cognitive function in hemodialysis (HD) patients and compared the Korean versions of the Montreal Cognitive Assessment (K-MoCA) and of the Mini-Mental State Examination (K-MMSE) to identify the better cognitive screening instrument in these patients. Thirty patients undergoing hemodialysis and 30 matched reference group of apparently healthy control were included. All subjects underwent the K-MoCA, K-MMSE and a neuropsychological test battery to measure attention, visuospatial function, language, memory and executive function. All cognitive data were converted to z-scores with appropriate age and education level prior to group comparisons. Cognitive performance 1.0 SD below the mean was defined as modest cognitve impairment while 1.5 below the mean was defined as severe cognitive impairment. Modest cognitive impairment in memory plus other cognitive domains was detected in 27 patients (90%) while severe cognitive impairment in memory plus other cognitive domains was detected in 23 (77%) patients. Total scores in the K-MoCA were significantly lower in HD patients than in the reference group. However, no significant group difference was found in the K-MMSE. The K-MMSE ROC AUC (95% confidence interval) was 0.72 (0.59-0.85) and K-MoCA ROC AUC was 0.77 (0.65-0.89). Cognitive impairment is common but under-diagnosed in this population. The K-MoCA seems to be more sensitive than the K-MMSE in HD patients.

Major depressive disorder with psychotic features may lead to misdiagnosis of dementia: a case report and review of the literature.

PubMed

Wagner, Gerhardt S; McClintock, Shawn M; Rosenquist, Peter B; McCall, W Vaughn; Kahn, David A

2011-11-01

Major depressive disorder (MDD) with psychotic features is relatively frequent in patients with greater depressive symptom severity and is associated with a poorer course of illness and greater functional impairment than MDD without psychotic features. Multiple studies have found that patients with psychotic mood disorders demonstrate significantly poorer cognitive performance in a variety of areas than those with nonpsychotic mood disorders. The Mini Mental State Examination (MMSE) and the Dementia Rating Scale, Second Edition (DRS-2) are widely used to measure cognitive functions in research on MDD with psychotic features. Established total raw score cut-offs of 24 on the MMSE and 137 on the DRS-2 in published manuals suggest possible global cognitive impairment and dementia, respectively. Limited research is available on these suggested cut-offs for patients with MDD with psychotic features. We document the therapeutic benefit of electroconvulsive therapy (ECT), which is usually associated with short-term cognitive impairment, in a 68-year-old woman with psychotic depression whose MMSE and DRS-2 scores initially suggested possible global cognitive impairment and dementia. Over the course of four ECT treatments, the patient's MMSE scores progressively increased. After the second ECT treatment, the patient no longer met criteria for global cognitive impairment. With each treatment, depression severity, measured by the 24-item Hamilton Rating Scale for Depression, improved sequentially. Thus, the suggested cut-off scores for the MMSE and the DRS-2 in patients with MDD with psychotic features may in some cases produce false-positive indications of dementia.

Finger displacement in Parkinson disease: up? down? sideways?

PubMed

Lieberman, Abraham; Dhall, Rohit; Salins, Naomi; Sadreddin, Arshia; Moguel-Cobos, Guillermo; Karis, John; Krishnamurthi, Narayanan

2014-05-01

We previously reported that patients with tremor preponderant Parkinson disease (PD) displayed upward or lateral displacement of their more tremulous finger when they pointed both their index fingers at a target and closed their eyes for 15 seconds. In this study, we examined the phenomenon in 104 PD patients: 72 patients without tremor and 32 with minimal tremor to see if the displacement is related to the disease or the tremor. Sixty-eight of the 72 patients without tremor, 94%, exhibited finger displacement suggesting the phenomenon is related to the disease. None of the 104 patients were demented: mini-mental status examination (MMSE) score 29.0 ± 0. 75. Ninety patients displayed upward displacement (56 patients) or lateral or medial displacement (34 patients). MMSE score of the 90 patients: 29.2 ± 0.74 with no score < 28. Eight patients (6 without tremor) displayed downward displacement. MMSE score of the 8 patients: 27.5 ± 0.35 with 5 having MMSE score of 27. Although not significant the results suggest that patients with downward displacement and lower MMSE score may be evolving a dementia. Upward displacement with eyes closed for 15 seconds requires an ability to "remember" the position of the finger in space and to alter tone to overcome gravity. Downward displacement implies an inability to "remember" the position of the finger in space an inability to overcome the effects of gravity. This may be more likely in patients who are evolving a dementia. Two patients, with PD-like symptoms, and specific anatomical abnormalities are also presented as they illustrate the anatomy of finger displacement.

Cognitive abilities screening instrument-short form, mini-mental state examination and functional activities questionnaire in the illiterate elderly.

PubMed

Rezende, Gabriela Pravatta; Cecato, Juliana; Martinelli, José Eduardo

2013-01-01

Dementia prevalence is increasing in developing countries due to population aging. Brief tests for assessing cognition and activities of daily living are very useful for the diagnosis of dementia by the clinician. Low education, particularly illiteracy, is a hindrance to the diagnosis of dementia in several regions of the world. To compare the Brazilian version of the Cognitive Abilities Screening Instrument-Short Form (CASI-S) with the Mini-Mental State Examination (MMSE) and Pfeffer Functional Activities Questionnaire (PFAQ) for the diagnosis of dementia in illiterate elderly. A cross-sectional study with illiterate elderly of both genders seen at the outpatient clinics of the Institute of Gerontology and Geriatrics Jundiaí, São Paulo state was performed. Spearman's correlation coefficient was used to correlate CASI-S, MMSE and PFAQ scores. The sample comprised 29 elderly over 57 years old whose mean scores on the CASI-S (scores ranging from 3 to 23) and the MMSE (scores ranging from 2 to 23) were 11.69 and 12.83, respectively. There was a strong significant correlation between the CASI-S and MMSE (r=0.75, p<0.001) and a moderate correlation coefficient that was significant and negative between the PFAQ and CASI-S (r= -0.53 p=0.003),similar to that between the MMSE and PFAQ (r= -0.41 p=0.025). The Brazilian version of the CASI-S demonstrates ease of application and correction in the illiterate elderly, and warrants further studies regarding its applicability for the diagnosis of dementia in populations with a heterogeneous educational background.

Correlates of Level and Change in the Mini-Mental State Examination

ERIC Educational Resources Information Center

Soubelet, Andrea; Salthouse, Timothy A.

2011-01-01

The goal of the current project was to determine (a) the cognitive abilities assessed by the Mini Mental State Examination (MMSE; M. F. Folstein, S. E. Folstein, & P. R. McHugh, 1975), (b) whether the same abilities are associated with MMSE performance among people of different ages, and (c) whether the same abilities are involved in changes…

Characteristic differences in the mini-mental state examination used in Asian countries.

PubMed

Shim, Yong S; Yang, Dong Won; Kim, Hee-Jin; Park, Young Ho; Kim, SangYun

2017-07-21

The mini-mental state examination (MMSE) was adapted by individual countries according to their languages and cultures, though it has not been systematically compared. The objective of this study was to compare the linguistic and cultural variations of the MMSE used in various Asian countries. With this, we can analyze the strengths and weaknesses of the MMSE and consider using a common version in future international clinical studies in Asia. We collected the MMSEs used in 11 Asian nations. After translating those into English, we compared them to understand the differences in the questionnaires with regard to cultural aspects. Many items may be applicable or comparable with a little modification, for Asian countries. However, attention and calculation and repetition may be incomparable. There were some differences in the contents and the ways to administer. The lack of consideration of the cultural differences and their influences on the interpretation of the same cognitive test makes cross-cultural studies difficult. Some items of MMSE tasks need readjusting for, if any, multi-national studies. This study might serve as a first step in the development of a standardized cross-cultural cognitive instrument, especially in Asia.

Tai Ji Quan and global cognitive function in older adults with cognitive impairment: a pilot study.

PubMed

Li, Fuzhong; Harmer, Peter; Liu, Yu; Chou, Li-Shan

2014-01-01

This study evaluated whether Tai Ji Quan: Moving for Better Balance (TJQMBB) could improve global cognitive function in older adults with cognitive impairment. Using a nonrandomized control group pretest-posttest design, participants aged ≥65 years who scored between 20 and 25 on the Mini-Mental State Examination (MMSE) were allocated into either a 14-week TJQMBB program (n=22) or a control group (n=24). The primary outcome was MMSE as a measure of global cognitive function with secondary outcomes of 50-ft speed walk, Timed Up&Go, and Activities-Specific Balance Confidence (ABC) scale. At 14 weeks, Tai Ji Quan participants showed significant improvement on MMSE (mean=2.26, p<0.001) compared to controls (mean=0.63, p=0.08). Similarly, Tai Ji Quan participants performed significantly better compared to the controls in both physical performance and balance efficacy measures (p<0.05). Improvement in cognition as measured by MMSE was related to improved physical performance and balance efficacy. These results provide preliminary evidence of the utility of the TJQMBB program to promote cognitive function in older adults in addition to physical benefits. Copyright © 2014 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

'Yes' ifs, ands or buts: examining performance and correlates of the repetition task in the mini-mental state examination.

PubMed

Werner, P; Heinik, J; Lin, R; Bleich, A

1999-09-01

The aim of this study was to examine whether the type of sentence used in the repetition task included in the Mini-Mental State Examination (MMSE) affected performance in a group of 79 demented and 19 non-demented Hebrew-speaking elderly persons. The cognitive functioning of the participants was assessed using the MMSE and CAMCOG examinations. The performance of the repetition task was evaluated by using three sentences: the literal translation of the English language expression used in the original MMSE; a well-known Hebrew proverb consisting of monosyllabic words and rhythmic effects; and another well-known Hebrew proverb without such attributes. Only a third of the participants successfully repeated the literally translated expression. It showed low predictive value and was highly affected by education. The well-known Hebrew monosyllabic proverb showed moderate predictive value but no discriminatory ability. The other well-known Hebrew proverb performed the best. The translation of the repetition task in the MMSE to other languages is problematic. Strict adherence to the original language proved to be the least desirable choice. Copyright 1999 John Wiley & Sons, Ltd.

Method and apparatus for communicating computer data from one point to another over a communications medium

DOEpatents

Arneson, Michael R [Chippewa Falls, WI; Bowman, Terrance L [Sumner, WA; Cornett, Frank N [Chippewa Falls, WI; DeRyckere, John F [Eau Claire, WI; Hillert, Brian T [Chippewa Falls, WI; Jenkins, Philip N [Eau Claire, WI; Ma, Nan [Chippewa Falls, WI; Placek, Joseph M [Chippewa Falls, WI; Ruesch, Rodney [Eau Claire, WI; Thorson, Gregory M [Altoona, WI

2007-07-24

The present invention is directed toward a communications channel comprising a link level protocol, a driver, a receiver, and a canceller/equalizer. The link level protocol provides logic for DC-free signal encoding and recovery as well as supporting many features including CRC error detection and message resend to accommodate infrequent bit errors across the medium. The canceller/equalizer provides equalization for destabilized data signals and also provides simultaneous bi-directional data transfer. The receiver provides bit deskewing by removing synchronization error, or skewing, between data signals. The driver provides impedance controlling by monitoring the characteristics of the communications medium, like voltage or temperature, and providing a matching output impedance in the signal driver so that fewer distortions occur while the data travels across the communications medium.

On codes with multi-level error-correction capabilities

NASA Technical Reports Server (NTRS)

Lin, Shu

1987-01-01

In conventional coding for error control, all the information symbols of a message are regarded equally significant, and hence codes are devised to provide equal protection for each information symbol against channel errors. However, in some occasions, some information symbols in a message are more significant than the other symbols. As a result, it is desired to devise codes with multilevel error-correcting capabilities. Another situation where codes with multi-level error-correcting capabilities are desired is in broadcast communication systems. An m-user broadcast channel has one input and m outputs. The single input and each output form a component channel. The component channels may have different noise levels, and hence the messages transmitted over the component channels require different levels of protection against errors. Block codes with multi-level error-correcting capabilities are also known as unequal error protection (UEP) codes. Structural properties of these codes are derived. Based on these structural properties, two classes of UEP codes are constructed.

Evaluation of the efficacy of animal-assisted therapy based on the reality orientation therapy protocol in Alzheimer's disease patients: a pilot study.

PubMed

Menna, Lucia Francesca; Santaniello, Antonio; Gerardi, Federica; Di Maggio, Annamaria; Milan, Graziella

2016-07-01

The aim of this study was to evaluate the efficacy of animal-assisted therapy (AAT) in elderly patients affected by Alzheimer's disease based on the formal reality orientation therapy (ROT) protocol. Our study was carried out at an Alzheimer's centre for 6 months. A homogeneous sample (age, Mini-Mental State Examination (MMSE), 15-item Geriatric Depression Scale (GDS)) of 50 patients was selected at random and successively. Patients were divided into three groups: (i) 20 patients received a course of AAT (AAT group) based on the ROT protocol; (ii) 20 patients were engaged exclusively in activities based on the ROT group; and (iii) 10 patients (control group) participated in no stimulations. MMSE and GDS were administered at time 0 (T0 ) and time 1 (T1 ) to all three groups. Differences within groups between T0 and T1 for GDS and MMSE scores were analyzed by Student's t-test. Differences between group means were analyzed using an anova test with the Bonferroni-Dunn test for post-hoc comparisons. Both the AAT group and ROT group had improved GDS scores and showed a slight improvement in terms of mood. On the GDS, the AAT group improved from 11.5 (T0 ) to 9.5 (T1 ), and the ROT group improved from 11.6 (T0 ) to 10.5 (T1 ). At the same time, a slight improvement in cognitive function, as measured by the MMSE, was observed. In the AAT group, mean MMSE was 20.2 at T0 and 21.5 at T1 , and in the ROT group, it was 19.9 at T0 and 20.0 at T1 . In the control group, the average values of both the GDS and MMSE remained unchanged. The Bonferroni-Dunn results showed statistically significant differences between groups, particularly between the AAT group and the other two (P < 0.001). Pet therapy interventions based on the formal ROT protocol were effective and, compared to the ROT, provided encouraging and statistically significant results. © 2015 The Authors. Psychogeriatrics © 2015 Japanese Psychogeriatric Society.

The sensitivity and specificity of subjective memory complaints and the subjective memory rating scale, deterioration cognitive observee, mini-mental state examination, six-item screener and clock drawing test in dementia screening.

PubMed

Ramlall, S; Chipps, J; Bhigjee, A I; Pillay, B J

2013-01-01

The effectiveness of dementia screening depends on the availability of suitable screening tools with good sensitivity and specificity to confidently distinguish normal age-related cognitive decline from dementia. The aim of this study was to evaluate the discriminant validity of 7 screening measures for dementia. A sample of 140 participants aged ≥60 years living in a residential facility for the aged were assessed clinically and assigned caseness for dementia using the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, text revised diagnostic criteria. Sensitivity and specificity of a selection of the following screening measures were tested using receiver operating characteristic (ROC) analysis for individual and combined tests: the Mini-Mental State Examination (MMSE), Six-Item Screener (SIS), Subjective Memory Complaint, Subjective Memory Complaint Clinical (SMCC), Subjective Memory Rating Scale (SMRS), Deterioration Cognitive Observee (DECO) and the Clock Drawing Test (CDT). Using ROC analyses, the SMCC, MMSE and CDT were found to be 'moderately accurate' in screening for dementia with an area under the curve (AUC) >0.70. The AUCs for the SIS (0.526), SMRS (0.661) and DECO (0.687) classified these measures as being 'less accurate'. At recommended cutoff scores, the SMCC had a sensitivity of 90.9% and specificity of 45.7%; the MMSE had a sensitivity of 63.6% and a specificity of 76.0%, and the CDT had a sensitivity of 44.4% and a specificity of 88.9%. Combining the SMCC and MMSE did not improve their predictive power except for a modest increase when using the sequential rule. The SMCC is composed of valid screening questions that have high sensitivity, are simple to administer and ideal for administration at the community or primary health care level as a first level of 'rule-out' screening. The MMSE can be included at a second stage of screening at the general hospital level and the CDT in specialist clinical settings. Sequential use of the SMCC and MMSE will improve the specificity of the former and the sensitivity of the latter. Copyright © 2013 S. Karger AG, Basel.

Use of scan overlap redundancy to enhance multispectral aircraft scanner data

NASA Technical Reports Server (NTRS)

Lindenlaub, J. C.; Keat, J.

1973-01-01

Two criteria were suggested for optimizing the resolution error versus signal-to-noise-ratio tradeoff. The first criterion uses equal weighting coefficients and chooses n, the number of lines averaged, so as to make the average resolution error equal to the noise error. The second criterion adjusts both the number and relative sizes of the weighting coefficients so as to minimize the total error (resolution error plus noise error). The optimum set of coefficients depends upon the geometry of the resolution element, the number of redundant scan lines, the scan line increment, and the original signal-to-noise ratio of the channel. Programs were developed to find the optimum number and relative weights of the averaging coefficients. A working definition of signal-to-noise ratio was given and used to try line averaging on a typical set of data. Line averaging was evaluated only with respect to its effect on classification accuracy.

Plasma Klotho and Cognitive Decline in Older Adults: Findings From the InCHIANTI Study

PubMed Central

Semba, Richard D.; Rosano, Caterina; Kalyani, Rita R.; Bandinelli, Stefania; Chia, Chee W.; Ferrucci, Luigi

2016-01-01

Background. The hormone klotho, encoded by the gene klotho, is primarily expressed in the kidney and choroid plexus of the brain. Higher klotho concentrations and certain genetic variants of klotho have been linked to better cognition; however, it is unknown whether klotho relates prospectively to slower cognitive decline in older adults. Methods: Plasma klotho was measured in 833 participants aged 55 or older without dementia enrolled in InCHIANTI, a prospective cohort study comprising Italian adults. Cognition was measured by Mini-Mental State Examination (MMSE) and Trail-Making Tests A and B (Trails A and Trails B) at enrollment and at 3 and 6 years after enrollment. We assessed whether klotho concentrations measured at the 3-year visit related to cognition and cognitive decline. Results: Each additional natural logarithm of klotho (pg/mL) was associated with 35% lower risk of meaningful decline in MMSE, defined as decline exceeding three points (relative risk = 0.65; 95% confidence interval 0.45, 0.95; p value = .02), and 0.75-point smaller average 3-year decline (baseline to 3-year visit) in MMSE (95% confidence interval 0.02, 1.48; p value = .04). No statistically significant associations were found between klotho and declining Trails A (relative risk = 0.99; 95% confidence interval 0.75, 1.32; p value = .97) and B (relative risk = 1.02; 95% confidence interval 0.84, 1.24; p value = .82). Conclusions: Higher plasma klotho concentrations were associated with lower risk of meaningful decline and smaller average decline in MMSE. We did not observe such findings with Trails A and B, perhaps because they test executive function and motor skills, whereas MMSE measures global cognition. Future studies should investigate mechanisms through which klotho may affect domain-specific cognitive changes. PMID:26297657

The level of cognitive function and recognition of emotions in older adults

PubMed Central

Singh-Manoux, Archana; Batty, G. David; Ebmeier, Klaus P.; Jokela, Markus; Harmer, Catherine J.; Kivimäki, Mika

2017-01-01

Background The association between cognitive decline and the ability to recognise emotions in interpersonal communication is not well understood. We aimed to investigate the association between cognitive function and the ability to recognise emotions in other people’s facial expressions across the full continuum of cognitive capacity. Methods Cross-sectional analysis of 4039 participants (3016 men, 1023 women aged 59 to 82 years) in the Whitehall II study. Cognitive function was assessed using a 30-item Mini-Mental State Examination (MMSE), further classified into 8 groups: 30, 29, 28, 27, 26, 25, 24, and <24 (possible dementia) MMSE points. The Facial Expression Recognition Task (FERT) was used to examine recognition of anger, fear, disgust, sadness, and happiness. Results The multivariable adjusted difference in the percentage of accurate recognition between the highest and lowest MMSE group was 14.9 (95%CI, 11.1–18.7) for anger, 15.5 (11.9–19.2) for fear, 18.5 (15.2–21.8) for disgust, 11.6 (7.3–16.0) for sadness, and 6.3 (3.1–9.4) for happiness. However, recognition of several emotions was reduced already after 1 to 2-point reduction in MMSE and with further points down in MMSE, the recognition worsened at an accelerated rate. Conclusions The ability to recognize emotion in facial expressions is affected at an early stage of cognitive impairment and might decline at an accelerated rate with the deterioration of cognitive function. Accurate recognition of happiness seems to be less affected by a severe decline in cognitive performance than recognition of negatively valued emotions. PMID:28977015

Screening cognitive impairment among institutionalized older Chinese men in Taiwan: a new minimum data set-based dementia screening tool is needed.

PubMed

Lin, Chu-Sheng; Lin, Ming-Hsien; Peng, Li-Ning; Chen, Liang-Kung; Hwang, Shinn-Jang; Lan, Chung-Fu

2011-01-01

Dementia screening is of great importance in various health settings for older people, long-term care facilities are no exception. The need for an effective dementia screening tool being culture sensitive is important. Minimum data set (MDS) is a population instrument for health care management in the world, which also covers dementia screening. The main purpose of this study was to evaluate the effectiveness of the MDS-based dementia screening tools among older Chinese men in the Veteran Home in Taiwan. Overall, 576 participants (mean age: 80.9±5.3 years, all males, 92.7% physically independent), 18.6% had cognitive impairment according to the mini-mental state examination (MMSE) (mean score: 26.7±3.9). However, the prevalence of cognitive impairment was 5.5% by MDS cognitive performance scale (CPS) and 18.9% by MDS cognition scale (MDS-COGS). The screening results of CPS and MDS-COGS were highly interrelated (γ=0.93, p<0.001), and MMSE scores were also significantly associated with CPS and MDS-COGS status (γ=-0.50, p<0.001 and γ=-0.52, p<0.001, respectively). Although the prevalence of cognitive impairment by MMSE and MDS-COGS are similar, the results are significantly inconsistent (p<0.001). In conclusion, both MDS-COGS and CPS were significantly correlated with MMSE scores, but significant inconsistence was noted between screening results of MMSE, CPS and MDS-COGS. Further study is needed to develop MDS-based dementia screening tools for older Chinese men in Taiwan. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Drug Burden Index and change in cognition over time in community-dwelling older men: the CHAMP study.

PubMed

Jamsen, Kris M; Gnjidic, Danijela; Hilmer, Sarah N; Ilomäki, Jenni; Le Couteur, David G; Blyth, Fiona M; Handelsman, David J; Naganathan, Vasi; Waite, Louise M; Cumming, Robert G; Bell, J Simon

2017-03-01

Anticholinergic and sedative medications are associated with acute cognitive impairment, but the long-term impact on change in cognition is unclear. This study investigated the effect of anticholinergic and sedative medications, quantified using the Drug Burden Index (DBI), on change in cognition over time in community-dwelling older men. This was a prospective cohort study of men aged ≥70 years in Sydney, Australia. DBI was assessed at baseline, 2, and 5 years. Cognitive performance was assessed using the Mini-Mental State Exam (MMSE) at each wave. Logistic quantile mixed-effects modelling was used to assess the adjusted effect of DBI on the median MMSE-time profile. Analyses were restricted to men with English-speaking backgrounds (n = 1059, 862, and 611 at baseline, 2, and 5 years). Overall, 292 (27.7%), 258 (29.9%), and 189 (31.3%) men used anticholinergic or sedative medications at baseline, 2, and 5 years. There was a concave relationship between MMSE and time, where higher DBI corresponded to lower MMSE scores (coefficient: -0.161; 95% CI: -0.250 to -0.071) but not acceleration of declining MMSE over time. Exposure to anticholinergic and sedative medications is associated with a small impairment in cognitive performance but not decline in cognition over time. KEY MESSAGES Exposure to anticholinergic and sedative medications, quantified using the Drug Burden Index, is associated with small cross-sectional impairments in cognitive performance. There was no evidence that exposure to anticholinergic and sedative medications is associated with accelerating decline in cognitive performance over a 5-year follow-up. Older people taking anticholinergic and sedative medications may derive immediate but small benefits in cognitive performance from clinical medication reviews to minimize or cease prescribing of these medications.

The relationship of bilingualism to cognitive decline: The Australian Longitudinal Study of Ageing.

PubMed

Mukadam, Naaheed; Jichi, Fatima; Green, David; Livingston, Gill

2018-02-01

We wished to clarify the link between bilingualism and cognitive decline, and examine whether improved executive function due to bilingualism may be a factor in preventing cognitive decline. We used the Australian Longitudinal Study of Ageing which collected data on 2087 participants aged over 65 over 20 years. We compared baseline demographics, health, and social characteristics between bilingual and non-bilingual participants. We used linear mixed models analysis to explore the effect of bilingualism on MMSE score over time and linear regression to explore the effect of bilingualism on baseline MMSE scores, controlling for pre-specified potential confounders. Bilingual participants had lower baseline MMSE scores than the non-bilingual population (mean difference = -2.3 points; 95% confidence intervals = 1.56-2.90). This was fully explained by education and National Adult Reading Test scores (17.4; standard deviation [SD] =7.7 versus 28.1; SD = 8.2) which also partly explained baseline executive function test scores differences. Bilingual and non-bilingual participants did not differ in MMSE decline over time (-0.33 points, P = 0.31) nor on baseline tests of executive function (-0.26, P = 0.051). In this cohort, education rather than bilingualism was a predictor of MMSE score, and being bilingual did not protect from cognitive decline. We conclude that bilingualism is complex, and when it is not the result of greater educational attainment, it does not always protect from cognitive decline. Neuroprotective effects of bilingualism over time may be attributable to the precise patterns of language use but not to bilingualism per se. Copyright © 2017 John Wiley & Sons, Ltd.

Validation of the Chinese version of the NUCOG cognitive screening tool in patients with epilepsy, dementia and other neurological disorders.

PubMed

Gao, Lan; Li, Shu-Chuen; Xia, Li; Pan, Songqing; Velakoulis, Dennis; Walterfang, Mark

2014-06-01

We aimed to develop and validate a Chinese version of the Neuropsychiatry Unit Cognitive Assessment Tool (NUCOG) for use in Chinese-speaking subjects internationally. Patients and healthy controls were recruited from two hospitals between July and October 2012. Receiver operating characteristic (ROC) curves were utilized to test criterion validity. Convergent validity was assessed via correlations between NUCOG and the Mini-Mental State Examination (MMSE). Reliability was measured by internal consistency (Cronbach's α). Patients with epilepsy (n=144), neurological diseases (n=81), dementia (n=44), and controls (n=260) completed the NUCOG and the MMSE. Overall, both NUCOG and MMSE scores differed significantly across the four groups with the highest scores in the control group and the lowest in the dementia group (p<0.0001). The NUCOG scores could differentiate between patients with certain seizure types, stroke and transient ischemic attack. Compared to the MMSE, the NUCOG exhibited a higher area under the ROC curve. The convergent validity was substantially correlated, and internal consistency was very high (0.922). The Chinese version of NUCOG was demonstrated to be a sensitive and reliable screening tool for cognitive impairment in a Chinese-speaking population not only in China, but also in countries where there is a sizeable population of ethnic Chinese. Additionally, our study also showed the NUCOG could better differentiate cognitive function in patients with certain seizure types, stroke and transient ischemic attack than the MMSE. This potentially expands the clinical usefulness of NUCOG, enabling clinicians to measure the cognitive profile of patients with epilepsy and ischemic cerebrovascular diseases. Copyright © 2013 Elsevier Ltd. All rights reserved.

Interaction Effects between HIV and Aging on Selective Neurocognitive Impairment.

PubMed

Ding, Yingying; Lin, Haijiang; Shen, Weiwei; Wu, Qionghai; Gao, Meiyang; He, Na

2017-12-01

HIV infection and aging are each associated with neurocognitive impairment (NCI). This study examined the combined effects of HIV infection and aging on NCI. We performed a cross-sectional survey among 345 HIV-infected and 345 HIV-uninfected participants aged at least 40 years. The International HIV Dementia Scale (IHDS) and Chinese version of Mini-mental State Examination (MMSE) were administered to screen for NCI. HIV-infected individuals had higher prevalence of NCI than uninfected individuals (46.7% vs 15.1% for IHDS using cut-off of ≤ 10; 17.1% vs 2.6% for MMSE). Significant main effects of HIV and age were observed on IHDS and MMSE composite scores and all domains except for HIV on attention and calculation. Significant interaction effects between HIV and age were observed on motor speed, orientation, registration and recall, and mainly attributed to the inferior performance of HIV-infected patients aged over 60 years. Among HIV-infected individuals, in multivariable logistic models, older age, depressive symptoms and history of nevirapine treatment were associated with NCI using both IHDS and MMSE, whereas lower education current smoker and current CD4 ≥ 800 cells/μL were associated only with NCI using IHDS, and hypertension was associated only with NCI using MMSE. Findings suggest that HIV and older age may confer interactive effects on cognitive function in several domains with older HIV-infected adults experiencing greater NCI, which requires further longitudinal investigation. Furthermore, HIV early diagnosis and treatment may prevent or reverse NCI, but extra attention should be given to adverse effects including metabolic changes associated with long-term treatment.

Correlates of self-reported, autobiographical, and mini-mental status examination defined memory deficits following electroconvulsive therapy in South India.

PubMed

Rajkumar, Anto P; Petit, Cheryl P; Rachana, Arun; Deinde, Funmi; Shyamsundar, G; Thangadurai, P; Jacob, Kuruthukulangara S

2018-04-01

Cognitive deficits, self-reported or found following electroconvulsive therapy (ECT), and their correlates are diverse. Despite the characteristics of people receiving ECT in Asia differ widely from the west, pertinent research from Asia remains sparse. We investigated the correlates of self-reported, mini-mental status examination (MMSE) defined, and autobiographical memory deficits in a cohort that received ECT in a south Indian tertiary-care setting. 76 consecutive consenting people were recruited within seven days of completing their ECT course. Memory was assessed by a subjective Likert scale, MMSE, and an autobiographical memory scale (AMS). Psychopathology was assessed by brief psychiatric rating scale, and serum cortisol levels were estimated by chemi-luminescence immunoassays. Relevant sociodemographic and clinical data were collected from the participants, and their medical records. The correlates were analysed using generalised linear models after adjusting for the effects of potential confounders. Self-reported, MMSE-defined, and autobiographical memory deficits were present in 27.6% (95%CI 17.6-37.7%), 42.1% (95%CI 31.0-53.2%), and 36.8% (95%CI 26.0-47.7%) of participants, respectively. Agreement between the memory deficits was poor. Age, less education, duration of illness, hypothyroidism, and past history of another ECT course were significantly associated with MMSE-defined deficits. Age, anaemia, past ECT course, and pre-ECT blood pressure were significantly associated with autobiographical memory deficits, while residual psychopathology and cortisol levels were significantly associated with self-reported memory deficits. Self-reported, MMSE-defined, and autobiographical memory deficits are common at the completion of ECT course, and their correlates differ. All service users receiving ECT need periodic cognitive assessments evaluating multiple cognitive domains. Copyright © 2018 Elsevier B.V. All rights reserved.

The effect of CPAP therapy on insulin-like growth factor and cognitive functions in obstructive sleep apnea patients.

PubMed

Kanbay, Asiye; Demir, Neslihan Cerrah; Tutar, Nuri; Köstek, Osman; Özer Şimşek, Zuhal; Buyukoglan, Hakan; Demir, Ramazan; Parrino, Liborio

2017-07-01

Cognitive impairment is common among patients with obstructive sleep apnea syndrome (OSAS). In this study, we aimed to investigate the effect of continuous positive airway pressure (CPAP) therapy on serum insulin-like growth factor-1 (IGF-1) levels and cognitive functions in patients with OSAS. Thirty-three patients with newly diagnosed OSAS and 17 healthy-control subjects enrolled in the study. All individuals completed the mini-mental state examination (MMSE) to evaluate cognitive function. Blood samples were taken at the end of the polysomnography in the morning and the same procedures were repeated 3 months after starting CPAP treatment. In the OSAS group, the baseline MMSE score was 23.5 ± 3.6, and serum IGF-1 level was 79.1 ± 36.1 ng/mL. Both values were significantly lower compared with the control group (mean MMSE score = 28.1 ± 1.4, P = 0.0001; mean serum IGF-1 level = 147.1 ± 49.1 ng/mL, P < 0.0001). Three months after CPAP treatment, OSAS patients showed a significant improvement in MMSE scores (26.5 ± 2.8, P = 0.0001) and serum IGF-1 level (129.1 ± 58.2, P = 0.0001). In contrast, baseline and third-month measurements for IGF-1 levels and MMSE scores were not significantly different in the control group. The results indicate that effective CPAP therapy in OSAS patients leads to significant improvement in cognitive functions and IGF-1 even in a short-term follow-up. Cognitive function assessment might be a part of evaluation in OSAS patients. © 2015 John Wiley & Sons Ltd.

Effects of transient versus chronic loneliness on cognitive function in older adults: Findings from the Chinese Longitudinal Healthy Longevity Survey

PubMed Central

Zhong, Bao-Liang; Chen, Shu-Lin; Conwell, Yeates

2016-01-01

Objectives Loneliness is a risk factor for poor cognitive function in older adults (OAs), however, to date, no studies have explored whether transient and chronic loneliness have differential effects on OAs’ cognitive function. The present study evaluates the impacts of transient versus chronic loneliness on cognitive function in OAs. Design A 6-year follow-up cohort study. Setting Rural and urban communities of 23 provinces in China. Participants 2995 OAs who were cognitively healthy (the modified Mini-mental State Examination [mMMSE] ≥ 14) and completed the 2005, 2008 and 2011 waves of the Chinese Longitudinal Healthy Longevity Survey. Measurements Self-report loneliness and mMMSE. Results Both transient (β=−0.389, t=−2.191, df=2994, P=0.029) and chronic loneliness (β=−0.640, t=−2.109, df=2994, P=0.035) were significantly associated with lower mMMSE scores six years later, net of potential confounding effects of baseline covariates. Sensitivity analyses found that regression coefficients of mMMSE scores on transient loneliness were statistically significant and relatively stable across samples with various levels of cognitive function. In contrast, coefficients of mMMSE scores on chronic loneliness were statistically significant only among samples with normal cognitive function and the absolute values of these coefficients increased with the degree of cognitive health of the analytic sample. In the sample with mMMSE≥21, the coefficient of chronic loneliness was 2.59 times as large as that of transient loneliness (−1.017 versus −0.392). Conclusions Both transient and chronic loneliness are significant predictors of cognitive decline in OAs. Relative to transient loneliness, chronic loneliness has more pronounced negative effects on the brain health of OAs. PMID:26905049

Cognitive function variations in postmenopausal women treated with continuous, combined HRT or tibolone. A comparison.

PubMed

Pan, Hsien-An; Wang, Shan-Tair; Pai, Ming-Chyi; Chen, Chih-Hung; Wu, Meng-Hsing; Huang, Ko-En

2003-05-01

To compare cognitive function in postmenopausal women receiving continuous hormone replacement therapy and those receiving tibolone. This was a 6-month, prospective, single-blind, single center, randomized study. A total of 50 healthy, postmenopausal women were enrolled. In the end, 40 women completed the 6-month follow-up. One group (23 subjects) received conjugated equine estrogens (CEE), 0.625 mg/d, and medroxyprogesterone acetate (MPA), 5 mg/d. The other group (17 subjects) received tibolone, 2.5 mg/d. Their serum estradiol levels and Cognitive Abilities Screening Instrument (CASI) and Mini-Mental State Examination (MMSE) scores were obtained before starting and after 3 and 6 months of treatment. There was a significant increase in the serum estradiol level in the CEE + MPA group, especially after 3 months of treatment, but there was no increase in the estradiol level in the tibolone group. The CASI and MMSE scores of the CEE + MPA group and the tibolone group after 3 and 6 months of treatment showed no significant difference between the two groups apart from the MMSE at the 3-month follow-up. We saw an increasing trend in CASI and MMSE scores after treatment in both groups; however, the increases were not statistically significant. The rate of increase of both CASI and MMSE scores in the CEE + MPA group was greater than in the tibolone group, though the difference was not significant. This preliminary study demonstrated that both CEE + MPA and tibolone can preserve cognitive function and may be able to prevent cognitive decline in postmenopausal women during short-term treatment. Our results also show that continuous, combined CEE + MPA seems to be marginally more effective than tibolone in improving cognitive processes; however, long-term study is needed to follow-up such effect.

Mild cognitive impairment is associated with poor physical function but not bone structure or density in late adulthood: findings from the Hertfordshire cohort study.

PubMed

Patel, A; Jameson, K A; Edwards, M H; Ward, K; Gale, C R; Cooper, C; Dennison, Elaine M

2018-04-24

This study investigated the association between mild cognitive impairment (MCI) and physical function and bone health in older adults. MCI was associated with poor physical performance but not bone mineral density or bone microarchitecture. Cross-sectional study to investigate the association between mild cognitive impairment (MCI) and physical performance, and bone health, in a community-dwelling cohort of older adults. Cognitive function of 222 men and 221 women (mean age 75.5 and 75.8 years in men and women, respectively) was assessed by the Strawbridge questionnaire and Mini Mental State Exam (MMSE). Participants underwent dual-energy X-ray absorptiometry (DXA), peripheral-quantitative computed tomography (pQCT) and high-resolution peripheral-quantitative computed tomography (HR-pQCT) scans to assess their bone density, strength and microarchitecture. Their physical function was assessed and a physical performance (PP) score was recorded. In the study, 11.8% of women and 8.1% of men were cognitively impaired on the MMSE (score < 24). On the Strawbridge questionnaire, 24% of women were deemed cognitively impaired compared to 22.3% of men. Cognitive impairment on the Strawbridge questionnaire was associated with poorer physical performance score in men but not in women in the unadjusted analysis. MMSE < 24 was strongly associated with the risk of low physical performance in men (OR 12.9, 95% CI 1.67, 99.8, p = 0.01). Higher MMSE score was associated with better physical performance in both sexes. Poorer cognitive function, whether assessed by the Strawbridge questionnaire, or by MMSE score, was not associated with bone density, shape or microarchitecture, in either sex. MCI in older adults was associated with poor physical performance, but not bone density, shape or microarchitecture.

Cognitive impairment associated with locomotive syndrome in community-dwelling elderly women in Japan.

PubMed

Nakamura, Misa; Tazaki, Fumie; Nomura, Kazuki; Takano, Taeko; Hashimoto, Masashi; Hashizume, Hiroshi; Kamei, Ichiro

2017-01-01

In our worldwide aging society, elderly people should maintain cognitive and physical function to help avoid health problems. Dementia is a major brain disease among elderly people, and is caused by cognitive impairment. The locomotive syndrome (LS) refers to a condition in which people require healthcare services because of problems associated with locomotion. The purpose of this study was to determine the association between cognitive impairment and LS. Study participants were 142 healthy elderly female volunteers living in a rural area in Japan. Cognitive function was assessed using the Mini-Mental State Examination (MMSE). A score of ≤26 points on the MMSE was used to indicate categorically defined poor cognitive performance (cognitive impairment). The LS was defined by a score ≥16 points, and non-LS as <16 points, on the 25-question Geriatric Locomotive Function Scale (GLFS-25). Twenty-one participants (14.8%) had an MMSE score ≤26, and 19.0% were found to have LS. Compared with the MMSE >26 group, the ≤26 group was significantly older, had a higher percentage of body fat, and a higher GLFS-25 score. Those with LS were significantly older, had a higher body mass index, a higher percentage of body fat, and a lower MMSE score. Participants in the LS group had higher odds of cognitive impairment than those without LS [odds ratio (OR) =3.08] by logistic regression analysis adjusted for age. Furthermore, participants with GLFS-25 scores ≥6 had higher odds of cognitive impairment than those with a GLFS-25 score <6 by logistic regression analysis adjusted for both age (OR =4.44), and age and percent body fat (OR =4.12). These findings suggest that a strong relationship exists between the early stage of decreased motor function and cognitive impairment.

Cognitive abilities screening instrument-short form, mini-mental state examination and functional activities questionnaire in the illiterate elderly

PubMed Central

Rezende, Gabriela Pravatta; Cecato, Juliana; Martinelli, José Eduardo

2013-01-01

Dementia prevalence is increasing in developing countries due to population aging. Brief tests for assessing cognition and activities of daily living are very useful for the diagnosis of dementia by the clinician. Low education, particularly illiteracy, is a hindrance to the diagnosis of dementia in several regions of the world. OBJECTIVES To compare the Brazilian version of the Cognitive Abilities Screening Instrument-Short Form (CASI-S) with the Mini-Mental State Examination (MMSE) and Pfeffer Functional Activities Questionnaire (PFAQ) for the diagnosis of dementia in illiterate elderly. METHODS A cross-sectional study with illiterate elderly of both genders seen at the outpatient clinics of the Institute of Gerontology and Geriatrics Jundiaí, São Paulo state was performed. Spearman's correlation coefficient was used to correlate CASI-S, MMSE and PFAQ scores. RESULTS The sample comprised 29 elderly over 57 years old whose mean scores on the CASI-S (scores ranging from 3 to 23) and the MMSE (scores ranging from 2 to 23) were 11.69 and 12.83, respectively. There was a strong significant correlation between the CASI-S and MMSE (r=0.75, p<0.001) and a moderate correlation coefficient that was significant and negative between the PFAQ and CASI-S (r= –0.53 p=0.003),similar to that between the MMSE and PFAQ (r= –0.41 p=0.025). CONCLUSION The Brazilian version of the CASI-S demonstrates ease of application and correction in the illiterate elderly, and warrants further studies regarding its applicability for the diagnosis of dementia in populations with a heterogeneous educational background. PMID:29213866

[Effects of physical activity on cognitive functions, balance and risk of falls in elderly patients with Alzheimer's dementia].

PubMed

Hernandez, Salma S S; Coelho, Flávia G M; Gobbi, Sebastião; Stella, Florindo

2010-01-01

To analyze the effects of regular, systematic and supervised activity on the cognitive functions, balance and risk of falls of elderly patients with Alzheimer's Dementia (AD). Sixteen elderly patients (mean age 78.5+/-6.8 years) were divided into two groups: intervention group (IG; n=9) and routine group (RG; n=7). The IG exercised systematically for six months, and both groups were submitted to the following tests: Mini-Mental State Examination (MMSE), Berg Balance Scale (BBS), Timed Up-and-Go (TUG) and the agility/dynamic balance (AGIBAL) item of the American Alliance for Health, Physical Education, Recreation and Dance (AAHPERD) test battery. There was a statistically significant interaction (two-way ANOVA; F1,14=32.07; p=0.01) between groups and moments for the AGIBAL. The Mann Whitney U test indicated significant differences between groups (p=0.03), only at the post-intervention moment for the TUG measured in steps and for BBS. Therefore, no significant intergroup differences were found for the TUG, BBS and MMSE at the pre-intervention moment or at post-intervention moment for the TUG measured in seconds and MMSE. The intragroup analysis by means of the Wilcoxon test showed a significant decline in the TUG, BBS and MMSE for the RG, but not for the IG. Spearman's coefficient showed a significant correlation between the results of the MMSE and AGIBAL. Physical activity may be an important non-pharmacological approach that can benefit cognitive functions and balance and reduce the risk of falls. Moreover, agility and balance are associated with cognitive functions in elderly patients with AD.

Effects of Exercise on Cognitive Function in Older People with Dementia: A Randomized Controlled Trial.

PubMed

Toots, Annika; Littbrand, Håkan; Boström, Gustaf; Hörnsten, Carl; Holmberg, Henrik; Lundin-Olsson, Lillemor; Lindelöf, Nina; Nordström, Peter; Gustafson, Yngve; Rosendahl, Erik

2017-01-01

Although physical exercise has been suggested to influence cognitive function, previous exercise studies show inconsistent results in people with dementia. To investigate effects of exercise on cognitive function in people with dementia. The Umeå Dementia and Exercise (UMDEX) study, a cluster-randomized controlled trial, was set in 16 nursing homes in Umeå, Sweden. One hundred-and-forty-one women and 45 men with dementia; mean age of 85 y and mean Mini-Mental State Examination (MMSE) score of 15, were randomized to a High-Intensity Functional Exercise program or a seated attention control activity. Blinded assessors measured global cognitive function using the MMSE and the Alzheimer's disease Assessment Scale - Cognitive subscale (ADAS-Cog), and executive function using Verbal fluency (VF) at baseline and 4 months (directly after intervention completion), and MMSE and VF at 7 months. Linear mixed models showed no between-group effects in mean difference from baseline (95% confidence intervals, CI) at 4 months in MMSE (-0.27; 95% CI -1.4 to 0.87, p = 0.644), ADAS-Cog (-1.04, 95% CI -4 to 1.92, p = 0.491), or VF (-0.53, 95% CI -1.42 to 0.35, p = 0.241) or at 7 months in MMSE (-1.15, 95% CI -2.32 to 0.03, p = 0.056) or VF (-0.18, 95% CI -1.09 to 0.74, p = 0.707). A 4-month, high-intensity functional exercise program had no superior effects on global cognition or executive function in people with dementia living in nursing homes when compared with an attention control activity.

Long-term cumulative depressive symptom burden and risk of cognitive decline and dementia among very old women.

PubMed

Zeki Al Hazzouri, Adina; Vittinghoff, Eric; Byers, Amy; Covinsky, Ken; Blazer, Dan; Diem, Susan; Ensrud, Kristine E; Yaffe, Kristine

2014-05-01

Depressive symptoms and cognitive outcomes are strongly interrelated. Despite that rates of depressive symptoms fluctuate during late life, little is known about the impact of long-term cumulative depressive symptom burden on cognitive decline and dementia in older adults. This study examines the association of nearly 20 years of cumulative depressive symptoms with cognitive outcomes in a cohort of older women. We assessed depressive symptoms in 7,240 women using the Geriatric Depression scale (GDS) at serial visits. We used a Poisson model with random slopes to estimate GDS trajectories for each participant from baseline to death or end of follow-up, and then characterized depressive symptom burden by quartile of the area under the curve. We assessed cognitive outcomes using repeated measures of the Mini-Mental State Examination (MMSE) and Trails B score over 20 years, Year-20 neuropsychological test battery, and adjudicated dementia and mild cognitive impairment (MCI). Adjusting for potential confounders, compared with women in the lowest quartile of cumulative depressive symptoms burden, women in the highest quartile had 21% more MMSE errors over time (95% CI = 17%, 26%), 20% worse Trails B score over time (95% CI = 17%, 23%), worse scores on most of the Year-20 cognitive tests, and a twofold greater likelihood of developing dementia or MCI (95% CI = 1.48, 3.11). Long-term cumulative depressive symptom burden was associated with cognitive decline and risk of dementia or MCI. Older adults with a history of depression should be closely monitored for recurrent episodes or unresolved depressive symptoms as well as any cognitive deficits.

Comparison of Three Cognitive Screening Tools in Older Urban and Regional Aboriginal Australians.

PubMed

Radford, Kylie; Mack, Holly A; Draper, Brian; Chalkley, Simon; Delbaere, Kim; Daylight, Gail; Cumming, Robert G; Bennett, Hayley; Broe, Gerald A

2015-01-01

Validated cognitive screening tools for use in urban and regional Aboriginal populations in Australia are lacking. In a cross-sectional community-based study, 235 participants were assessed on the Mini-Mental State Examination (MMSE), the Rowland Universal Dementia Assessment Scale (RUDAS) and an urban modification of the Kimberley Indigenous Cognitive Assessment (mKICA). Performance on these cognitive screening tools was compared to dementia diagnosis by clinical consensus. All tests were culturally acceptable with good psychometric properties. Receiver operating characteristic curve analyses revealed that the MMSE and mKICA were the most accurate. The MMSE is an effective cognitive screening tool in urban Aboriginal populations. The mKICA is a good alternative when illiteracy, language or cultural considerations deem it appropriate. The RUDAS also has adequate validity in this population. © 2015 S. Karger AG, Basel.

One-dimensional error-diffusion technique adapted for binarization of rotationally symmetric pupil filters

NASA Astrophysics Data System (ADS)

Kowalczyk, Marek; Martínez-Corral, Manuel; Cichocki, Tomasz; Andrés, Pedro

1995-02-01

Two novel algorithms for the binarization of continuous rotationally symmetric real and positive pupil filters are presented. Both algorithms are based on the one-dimensional error diffusion concept. In our numerical experiment an original gray-tone apodizer is substituted by a set of transparent and opaque concentric annular zones. Depending on the algorithm the resulting binary mask consists of either equal width or equal area zones. The diffractive behavior of binary filters is evaluated. It is shown that the filter with equal width zones gives Fraunhofer diffraction pattern more similar to that of the original gray-tone apodizer than that with equal area zones, assuming in both cases the same resolution limit of device used to print both filters.

COMPASS: A computational model to predict changes in MMSE scores 24-months after initial assessment of Alzheimer's disease.

PubMed

Zhu, Fan; Panwar, Bharat; Dodge, Hiroko H; Li, Hongdong; Hampstead, Benjamin M; Albin, Roger L; Paulson, Henry L; Guan, Yuanfang

2016-10-05

We present COMPASS, a COmputational Model to Predict the development of Alzheimer's diSease Spectrum, to model Alzheimer's disease (AD) progression. This was the best-performing method in recent crowdsourcing benchmark study, DREAM Alzheimer's Disease Big Data challenge to predict changes in Mini-Mental State Examination (MMSE) scores over 24-months using standardized data. In the present study, we conducted three additional analyses beyond the DREAM challenge question to improve the clinical contribution of our approach, including: (1) adding pre-validated baseline cognitive composite scores of ADNI-MEM and ADNI-EF, (2) identifying subjects with significant declines in MMSE scores, and (3) incorporating SNPs of top 10 genes connected to APOE identified from functional-relationship network. For (1) above, we significantly improved predictive accuracy, especially for the Mild Cognitive Impairment (MCI) group. For (2), we achieved an area under ROC of 0.814 in predicting significant MMSE decline: our model has 100% precision at 5% recall, and 91% accuracy at 10% recall. For (3), "genetic only" model has Pearson's correlation of 0.15 to predict progression in the MCI group. Even though addition of this limited genetic model to COMPASS did not improve prediction of progression of MCI group, the predictive ability of SNP information extended beyond well-known APOE allele.

Sources of Variation on the Mini-Mental State Examination in a Population-Based Sample of Centenarians

PubMed Central

Dai, Ting; Davey, Adam; Woodard, John L.; Miller, L. Stephen; Gondo, Yasuyuki; Kim, Seock-Ho; Poon, Leonard W.

2013-01-01

Centenarians represent a rare but rapidly growing segment of the oldest-old. This study presents item-level data from the Mini-Mental State Examination (MMSE, M=16.2, SD=8.8, Range 0–30) in a cross-sectional, population-based sample of 244 centenarians and near-centenarians (aged 98–108, 16% men, 21% African-American, 38% community-dwelling) from the Georgia Centenarian Study (2001–2008) by age, education, sex, race, and residential status. Multiple-Indicator Multiple-Causes (MIMIC) models were used to identify systematic domain-level differences on MMSE scores by key demographic characteristics in this age group. Indirect effects of age, educational attainment, race, and residential status were found on MMSE scores. Direct effects were limited to concentration for education and race, and orientation for residential status. Mean levels of cognitive functioning in centenarians were low, with mean values below most commonly-used cut-offs. Overall scores on the MMSE differed as a function of age, education, race, and residential status, with differences in scale performance limited primarily to concentration and orientation, with no evidence for interactions among centenarian characteristics. Adjusting for education was not sufficient to account for differences by race; adjusting for residential status was not sufficient to account for differences by age. PMID:23889552

Prognosis of Treatment Outcomes by Cognitive and Physical Scales.

PubMed

Jakavonytė-Akstinienė, Agnė; Dikčius, Vytautas; Macijauskienė, Jūratė

2018-01-01

The aim of this study was to assess the possibility of using scales for measuring cognitive and physical functions for a prognosis of care outcomes in elderly patients. The survey was carried out in one of the Vilnius City Hospitals for Nursing and Support Treatment. A total number of 177 respondents were involved in the study. The Mini-Mental State Examination (MMSE), The Barthel Index (BI) and The Morse Fall Scale were used. A statistically significant correlation was revealed between the scores of MMSE and BI (Pearson R = 0.41, p < 0.01); those with severe cognitive impairment were more dependent. A statistically significant correlation (Pearson R = -0.181, p < 0.01) was reported between the scores of MMSE and the Morse Fall Scale - the risk of falling was higher in patients with severe cognitive impairment. The Morse Fall Scale was not suitable for the prognosis of outcomes. The MMSE was suitable for the prognosis of a patient's discharge. The Barthel Index should be considered as the most suitable tool for the prognosis of care outcomes: the sum-score of the Barthel Index above 25 may suggest that the patient would be discharged home; the sum-score below this level was associated with a higher likelihood of patient death.

[Cognitive disorders and falls: experience of the Lille multidisciplinary falls service].

PubMed

Maeker, E; Bombois, S; Pardessus, V; Tiberghien, F; Dipompeo, C; Thevenon, A; Dewailly, P; Puisieux, F

2005-04-01

Falls and dementia are two major public health problems which concern the elderly population. Cognitive impairment, as a result of Alzheimer's disease or non-Alzheimer dementia, is recognized as a risk factor for falling. Through the experience of the Multidisciplinary Falls Consultation, our aims were first, to evaluate the prevalence of a cognitive decline among outpatients who consult for falls, and second, to determine whether the cognitive impairment was known and diagnosed before the consultation or not. Data concerning the first 300 outpatients who completed the initial evaluation are reported. Each patient was assessed by a geriatrician, a neurologist, and a physiatrist, who visited him or her at home. Cognitive impairment was defined as a Mini-Mental State Examination (MMSE) score<24. Of the 300 patients, 228 patients completed the initial evaluation. Among them, 97 (42.5 percent) had a MMSE score<24; 55 had mild stage dementia (MMSE score between 23 and 18) and 42 were at a moderate or severe stage (MMSE score< or =17/30). The cognitive decline was not diagnosed before the consultation in 80 of the 97 patients (82 percent). The findings show that a large proportion of old persons presenting with gait disturbance at the Multidisciplinary Falls Consultation have an underlying cognitive decline. Assessment of cognitive functions is required in every elderly faller.

Engaged Lifestyle, Personality, and Mental Status Among Centenarians

PubMed Central

Baenziger, Joan; MacDonald, Maurice; Siegler, Ilene C.; Poon, Leonard W.

2010-01-01

This study assessed engaged lifestyle activities (e.g., volunteering, traveling, and public speaking) for centenarians of the Georgia Centenarian Study. A total of 285 centenarians and near-centenarians (i.e., 98 years and older) and their proxy informants participated in this study. The Mini-Mental Status Examination (MMSE) was assessed for all centenarians, and proxy informants reported on lifestyle activities and personality traits of the centenarians. Results suggested that participants who had volunteered, traveled, and those who had given public talks and balanced their checkbooks were more likely to show relatively high mental status scores (i.e., MMSE > 17). Personality traits were found to be moderators in the relationship between engaged lifestyle and mental status: Participants with high levels of Emotional Stability, Extraversion, Openness, and Conscientiousness and with high levels of engaged lifestyle were more likely to show relatively high mental status scores (i.e., MMSE > 17), whereas participants with low levels of Emotional Stability, Extraversion, Openness, Agreeableness, and Conscientiousness and with low levels of engaged lifestyle were more likely to show relatively low mental status scores (i.e., MMSE < 18). The results suggest that engaged lifestyle, particularly in combination with personality traits, plays an important role in the level of cognitive functioning among oldest old adults. PMID:21132076

Predicting the Rate of Cognitive Decline in Alzheimer Disease: Data From the ICTUS Study.

PubMed

Canevelli, Marco; Kelaiditi, Eirini; Del Campo, Natalia; Bruno, Giuseppe; Vellas, Bruno; Cesari, Matteo

2016-01-01

Different rates of cognitive progression have been observed among Alzheimer disease (AD) patients. The present study aimed at evaluating whether the rate of cognitive worsening in AD may be predicted by widely available and easy-to-assess factors. Mild to moderate AD patients were recruited in the ICTUS study. Multinomial logistic regression analysis was performed to measure the association between several sociodemographic and clinical variables and 3 different rates of cognitive decline defined by modifications (after 1 year of follow-up) of the Mini Mental State Examination (MMSE) score: (1) "slow" progression, as indicated by a decrease in the MMSE score ≤1 point; (2) "intermediate" progression, decrease in the MMSE score between 2 and 5 points; and (3) "rapid" progression, decrease in the MMSE score ≥6 points. A total of 1005 patients were considered for the present analyses. Overall, most of the study participants (52%) exhibited a slow cognitive course. Higher ADAS-Cog scores at baseline were significantly associated with both "intermediate" and "rapid" decline. Conversely, increasing age was negatively associated with "rapid" cognitive worsening. A slow progression of cognitive decline is common among AD patients. The influence of age and baseline cognitive impairment should always be carefully considered when designing AD trials and defining study populations.

Using sediment 'fingerprints' to assess sediment-budget errors, north Halawa Valley, Oahu, Hawaii, 1991-92

USGS Publications Warehouse

Hill, B.R.; DeCarlo, E.H.; Fuller, C.C.; Wong, M.F.

1998-01-01

Reliable estimates of sediment-budget errors are important for interpreting sediment-budget results. Sediment-budget errors are commonly considered equal to sediment-budget imbalances, which may underestimate actual sediment-budget errors if they include compensating positive and negative errors. We modified the sediment 'fingerprinting' approach to qualitatively evaluate compensating errors in an annual (1991) fine (<63 ??m) sediment budget for the North Halawa Valley, a mountainous, forested drainage basin on the island of Oahu, Hawaii, during construction of a major highway. We measured concentrations of aeolian quartz and 137Cs in sediment sources and fluvial sediments, and combined concentrations of these aerosols with the sediment budget to construct aerosol budgets. Aerosol concentrations were independent of the sediment budget, hence aerosol budgets were less likely than sediment budgets to include compensating errors. Differences between sediment-budget and aerosol-budget imbalances therefore provide a measure of compensating errors in the sediment budget. The sediment-budget imbalance equalled 25% of the fluvial fine-sediment load. Aerosol-budget imbalances were equal to 19% of the fluvial 137Cs load and 34% of the fluval quartz load. The reasonably close agreement between sediment- and aerosol-budget imbalances indicates that compensating errors in the sediment budget were not large and that the sediment-budget imbalance as a reliable measure of sediment-budget error. We attribute at least one-third of the 1991 fluvial fine-sediment load to highway construction. Continued monitoring indicated that highway construction produced 90% of the fluvial fine-sediment load during 1992. Erosion of channel margins and attrition of coarse particles provided most of the fine sediment produced by natural processes. Hillslope processes contributed relatively minor amounts of sediment.

Relationship between dietary pattern and cognitive function in elderly patients with type 2 diabetes mellitus.

PubMed

Enomoto, Mari; Yoshii, Hidenori; Mita, Tomoya; Sanke, Haruna; Yokota, Ayako; Yamashiro, Keiko; Inagaki, Noriko; Gosho, Masahiko; Ohmura, Chie; Kudo, Kayo; Watada, Hirotaka; Onuma, Tomio

2015-08-01

To analyse the relationships between dietary patterns and cognitive function in elderly patients with type 2 diabetes mellitus (T2DM). Patients with T2DM completed a 3-day dietary record and Mini-mental State Examination (MMSE). Dietary patterns were identified by factor analysis. The study included 73 patients and identified five dietary patterns, one of which was characterized by high loading for vegetables and fish. A higher consumption of vegetables and fish was significantly associated with improved MMSE score (unadjusted model, model adjusted for age and sex, and model adjusted for age, sex, education, diabetic nephropathy and alcohol consumption), and decreased prevalence of suspected mild dementia (unadjusted model, model adjusted for age and sex). A high score in the vegetables and fish dietary pattern was associated with high MMSE score and low prevalence of suspected mild dementia in elderly patients with T2DM. © The Author(s) 2015.

Topological Interference Management for K-User Downlink Massive MIMO Relay Network Channel.

PubMed

Selvaprabhu, Poongundran; Chinnadurai, Sunil; Li, Jun; Lee, Moon Ho

2017-08-17

In this paper, we study the emergence of topological interference alignment and the characterizing features of a multi-user broadcast interference relay channel. We propose an alternative transmission strategy named the relay space-time interference alignment (R-STIA) technique, in which a K -user multiple-input-multiple-output (MIMO) interference channel has massive antennas at the transmitter and relay. Severe interference from unknown transmitters affects the downlink relay network channel and degrades the system performance. An additional (unintended) receiver is introduced in the proposed R-STIA technique to overcome the above problem, since it has the ability to decode the desired signals for the intended receiver by considering cooperation between the receivers. The additional receiver also helps in recovering and reconstructing the interference signals with limited channel state information at the relay (CSIR). The Alamouti space-time transmission technique and minimum mean square error (MMSE) linear precoder are also used in the proposed scheme to detect the presence of interference signals. Numerical results show that the proposed R-STIA technique achieves a better performance in terms of the bit error rate (BER) and sum-rate compared to the existing broadcast channel schemes.

Topological Interference Management for K-User Downlink Massive MIMO Relay Network Channel

PubMed Central

Li, Jun; Lee, Moon Ho

2017-01-01

In this paper, we study the emergence of topological interference alignment and the characterizing features of a multi-user broadcast interference relay channel. We propose an alternative transmission strategy named the relay space-time interference alignment (R-STIA) technique, in which a K-user multiple-input-multiple-output (MIMO) interference channel has massive antennas at the transmitter and relay. Severe interference from unknown transmitters affects the downlink relay network channel and degrades the system performance. An additional (unintended) receiver is introduced in the proposed R-STIA technique to overcome the above problem, since it has the ability to decode the desired signals for the intended receiver by considering cooperation between the receivers. The additional receiver also helps in recovering and reconstructing the interference signals with limited channel state information at the relay (CSIR). The Alamouti space-time transmission technique and minimum mean square error (MMSE) linear precoder are also used in the proposed scheme to detect the presence of interference signals. Numerical results show that the proposed R-STIA technique achieves a better performance in terms of the bit error rate (BER) and sum-rate compared to the existing broadcast channel schemes. PMID:28817071

Augmented burst-error correction for UNICON laser memory. [digital memory

NASA Technical Reports Server (NTRS)

Lim, R. S.

1974-01-01

A single-burst-error correction system is described for data stored in the UNICON laser memory. In the proposed system, a long fire code with code length n greater than 16,768 bits was used as an outer code to augment an existing inner shorter fire code for burst error corrections. The inner fire code is a (80,64) code shortened from the (630,614) code, and it is used to correct a single-burst-error on a per-word basis with burst length b less than or equal to 6. The outer code, with b less than or equal to 12, would be used to correct a single-burst-error on a per-page basis, where a page consists of 512 32-bit words. In the proposed system, the encoding and error detection processes are implemented by hardware. A minicomputer, currently used as a UNICON memory management processor, is used on a time-demanding basis for error correction. Based upon existing error statistics, this combination of an inner code and an outer code would enable the UNICON system to obtain a very low error rate in spite of flaws affecting the recorded data.

A preliminary study of the Six-Item Screener in detecting cognitive impairment.

PubMed

Chen, Mei-Rong; Guo, Qi-Hao; Cao, Xin-Yi; Hong, Zhen; Liu, Xiao-Hong

2010-08-01

The present retrospective study was to explore the clinical value of Six-Item Screener (SIS), which is constituted by 6 items from mini-mental status examination (MMSE), to identify cognitive impairment. A total number of 1976 patients aged over 50 years, from the Memory Clinic of Huashan Hospital were employed in a battery of neuropsychological tests including MMSE. Subjects with severe conditions, unable to cooperate, or having been previously enrolled, were excluded from this study. The employed subjects were divided into 3 groups: subjective memory complaints (SMCs) (475 cases), patients with mild cognitive impairment (MCI) (440 cases), and patients with Alzheimer's disease (AD) (1061 cases, including 555 mild, 339 moderate, and 167 severe). A total score of MMSE and a score of SIS composed of date, month, year, three-word delayed recall from MMSE were calculated. Data were analyzed based on educational background. The cut-off of SIS score was <2 for illiterate, <3 for elementary, and <4 for junior high school or above. The sensitivity and specificity of SIS for detecting mild AD were 88.5% and 78.3%, respectively, with an overall accuracy of 83.8%, while for detecting MCI, the sensitivity and specificity were 34.3% and 90.1%, respectively, with an overall accuracy of 63.2%. SIS is an effective and reliable instrument for dementia detection in outpatient department. However, it has limited value for MCI identification.

Improving detection of dementia in Asian patients with low education: combining the Mini-Mental State Examination and the Informant Questionnaire on Cognitive Decline in the Elderly.

PubMed

Narasimhalu, Kaavya; Lee, June; Auchus, Alexander P; Chen, Christopher P L H

2008-01-01

Previous work combining the Mini-Mental State Examination (MMSE) and Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) has been conducted in western populations. We ascertained, in an Asian population, (1) the best method of combining the tests, (2) the effects of educational level, and (3) the effect of different dementia etiologies. Data from 576 patients were analyzed (407 nondemented controls, 87 Alzheimer's disease and 82 vascular dementia patients). Sensitivity, specificity and AUC values were obtained using three methods, the 'And' rule, the 'Or' rule, and the 'weighted sum' method. The 'weighted sum' rule had statistically superior AUC and specificity results, while the 'Or' rule had the best sensitivity results. The IQCODE outperformed the MMSE in all analyses. Patients with no education benefited more from combined tests. There was no difference between Alzheimer's disease and vascular dementia populations in the predictive value of any of the combined methods. We recommend that the IQCODE be used to supplement the MMSE whenever available and that the 'weighted sum' method be used to combine the MMSE and the IQCODE, particularly in populations with low education. As the study population selected may not be representative of the general population, further studies are required before generalization to nonclinical samples. (c) 2007 S. Karger AG, Basel.

Clinically insubstantial cognitive side effects of bitemporal electroconvulsive therapy at 0.5 msec pulse width.

PubMed

Warnell, Ronald L; Swartz, Conrad M; Thomson, Alice

2011-11-01

We measured cognitive side effects from bitemporal electroconvulsive therapy (ECT) using stimuli of 0.5 msec pulse width 900 milliamperes (mA). Mini-Mental State Exam (MMSE) and 21-item Hamilton Rating Scale for Depression (HRSD-21) were rated within 36 hours before and 36 hours after a series of 6 bitemporal ECT sessions on 15 patients age ≥45. MMSE remained high after ECT (pre-ECT mean 29, standard deviation [SD] 1.60, post-ECT mean 28.53, SD 1.36) with no significant change. The mean HRSD-21 fell from 27.5 to 16.3. Post-ECT MMSE was significantly and markedly higher than in previous studies of bitemporal ECT; all had used ECT stimuli of pulse width at least 1 msec. With stimuli of 0.5 msec pulse width and 900 mA, 6 bitemporal ECTs did not decrease MMSE score. This result leaves no opportunity for further decrease in basic cognitive side effects, and complements published reports of stronger physiological effects with stimuli of 0.5 msec pulse width and 900 mA. ECT stimuli of 0.5 msec pulse width and 900 mA are more desirable than wider pulse widths. Six bitemporal ECT sessions using these stimuli generally will not have more cognitive side effects than treatments with other placements, allowing maintenance of full efficacy with clinically insubstantial side effects.

Evaluation of alternative model selection criteria in the analysis of unimodal response curves using CART

USGS Publications Warehouse

Ribic, C.A.; Miller, T.W.

1998-01-01

We investigated CART performance with a unimodal response curve for one continuous response and four continuous explanatory variables, where two variables were important (ie directly related to the response) and the other two were not. We explored performance under three relationship strengths and two explanatory variable conditions: equal importance and one variable four times as important as the other. We compared CART variable selection performance using three tree-selection rules ('minimum risk', 'minimum risk complexity', 'one standard error') to stepwise polynomial ordinary least squares (OLS) under four sample size conditions. The one-standard-error and minimum-risk-complexity methods performed about as well as stepwise OLS with large sample sizes when the relationship was strong. With weaker relationships, equally important explanatory variables and larger sample sizes, the one-standard-error and minimum-risk-complexity rules performed better than stepwise OLS. With weaker relationships and explanatory variables of unequal importance, tree-structured methods did not perform as well as stepwise OLS. Comparing performance within tree-structured methods, with a strong relationship and equally important explanatory variables, the one-standard-error-rule was more likely to choose the correct model than were the other tree-selection rules 1) with weaker relationships and equally important explanatory variables; and 2) under all relationship strengths when explanatory variables were of unequal importance and sample sizes were lower.

Map projections for global and continental data sets and an analysis of pixel distortion caused by reprojection

USGS Publications Warehouse

Steinwand, Daniel R.; Hutchinson, John A.; Snyder, J.P.

1995-01-01

In global change studies the effects of map projection properties on data quality are apparent, and the choice of projection is significant. To aid compilers of global and continental data sets, six equal-area projections were chosen: the interrupted Goode Homolosine, the interrupted Mollweide, the Wagner IV, and the Wagner VII for global maps; the Lambert Azimuthal Equal-Area for hemisphere maps; and the Oblated Equal-Area and the Lambert Azimuthal Equal-Area for continental maps. Distortions in small-scale maps caused by reprojection, and the additional distortions incurred when reprojecting raster images, were quantified and graphically depicted. For raster images, the errors caused by the usual resampling methods (pixel brightness level interpolation) were responsible for much of the additional error where the local resolution and scale change were the greatest.

[Mini Mental State Examination (MMSE): determination of cutoff scores according to age and educational level].

PubMed

Solias, A; Skapinakis, P; Degleris, N; Pantoleon, M; Katirtzoglou, E; Politis, A

2014-01-01

For the last 38 years, Mini Mental State Examination (MMSE) has been widely used as a dementia screening measure in everyday clinical practice as well as in both cohort and cross-sectional studies. Its validity and reliability for the Greek population has explicitly been documented. However, the effect of age and education on the subject's performance makes it necessary to reckon them in the estimation of the "cutoff score". The purpose of this study is to estimate the prevalence of dementia in Greek population and determine the "cutoff score" by age and education-corrected norms. Cross sectional study of 630 patients older than 55 years, who live independently in Ilion and Helioupolis Municipalities was conducted, 27.3% of the subjects tested in the study were diagnosed with memory disorder according to their MMSE scores and the validation for the Greek population. The effect of age and education to the subjects' performance was statistically significant (p=.000). The use of standard "cutoff score" was not proved to be useful for the personalized interpretation of the results, as documented by the fact that older individuals with lower education had a poorer performance relatively to younger, highly educated subjects. Comparatively to the group age of 55-60 years, the odds ratio after the age of 75 years varies from 2.58 to 4.91. Regarding the variable factor of education, the odds ratio for the first degree education graduates decreases from 1.43 to 3.19 for the third degree education graduates in comparison with the group of illiterates. In conclusion, the use of the "cutoff score" algorithm and the simultaneous estimation of age and education effect on MMSE score may prove useful for the proper evaluation of MMSE performance. According to the age and education of examine candidates in the community and the primary care, we propose the use of the 25th percentile as a more useful cutoff score in order to decrease the false positive results.

Cognitive problems in patients in a cardiac rehabilitation program after an out-of-hospital cardiac arrest.

PubMed

Boyce-van der Wal, L W; Volker, W G; Vliet Vlieland, T P M; van den Heuvel, D M J; van Exel, H J; Goossens, P H

2015-08-01

Estimate prevalence of cognitive problems due to hypoxic brain injury in out-of-hospital cardiac arrest (OHCA) survivors referred for cardiac rehabilitation and association with quality of life as well as autonomy and participation. Prospective cohort study. Consecutive OHCA patients. The Mini-Mental State Examination (MMSE), Cognitive Failures Questionnaire (CFQ) and Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) were administered 4 weeks after the OHCA. Cognitive problems were defined if MMSE <28, CFQ >32 or IQCODE >3.6. The Impact on Participation and Autonomy Questionnaire (IPAQ) (participation/autonomy), the SF-36 Health Survey (SF-36) (quality of life) and the Hospital Anxiety Depression Scale (HADS) (anxiety/depression) were administered. Correlations between cognitive problems and participation/autonomy and quality of life were calculated. 63 of 77 patients were male (82%), median age 59 years (range 15-84). MMSE median 29 (interquartile range 28-30), CFQ mean 20.9 (SD 9.4) and IQCODE mean 3.1 (SD 0.2). Eighteen patients (23%) scored positive for cognitive problems. Significant correlations were found between MMSE and IPAQ: autonomy inside (r = -0.38), family role (r = -0.26), autonomy outside (r = -0.32), social relations (r = -0.38) and social functioning (r = 0.32). MMSE was related to SF-36: social functioning (r = 0.32). The CFQ was related to IPAQ: autonomy outdoors (r = 0.29) and SF-36: bodily pain (r = -0.37), vitality (r = -0.25), mental health (r = -0.35) and role emotional (r = -0.40). The IQCODE was related to IPAQ: autonomy indoors (r = 0.26) and to SF-36: vitality (r = -0.33) and social functioning (r = -0.41). Twenty-three percent of the patients referred for cardiac rehabilitation showed cognitive problems. Associations were found between cognitive problems and several aspects of participation/autonomy and perceived quality of life. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Discrimination between stages of Alzheimer's disease with subsets of Mini-Mental State Examination items. An analysis of Consortium to Establish a Registry for Alzheimer's Disease data.

PubMed

Fillenbaum, G G; Wilkinson, W E; Welsh, K A; Mohs, R C

1994-09-01

To identify minimal sets of Mini-Mental State Examination (MMSE) items that can distinguish normal control subjects from patients with mild Alzheimer's disease (AD), patients with mild from those with moderate AD, and those with moderate from those with severe AD. Two randomly selected equivalent half samples. Results of logistic regression analysis from data from the first half of the sample were confirmed by receiver operating characteristic curves on the second half. Memory disorders clinics at major medical centers in the United States affiliated with the Consortium to establish a Registry for Alzheimer's Disease (CERAD). White, normal control subjects (n = 412) and patients with AD (n = 621) who met CERAD criteria; nonwhite subjects (n = 165) and persons with missing data (n = 27) were excluded. Three four-item sets of MMSE items that discriminate, respectively, (1) normal controls from patients with mild AD, (2) patients with mild from those with moderate AD, and (3) patients with moderate from those with severe AD. The MMSE items discriminating normal controls from patients with mild AD were day, date, recall of apple, and recall of penny; those discriminating patients with mild from those with moderate AD were month, city, spelling world backward, and county, and those discriminating patients with moderate from those with severe AD were floor of building, repeating the word table, naming watch, and folding paper in half. Performance on the first two four-item sets was comparable with that of the full MMSE; the third set distinguished patients with moderate from those with severe AD better than chance. A minimum set of MMSE items can effectively discriminate normal controls from patients with mild AD and between successive levels of severity of AD. Data apply only to white patients with AD. Performance in minorities, more heterogeneous groups, or normal subjects with questionable cognitive status has not been assessed.

Association of physical activity with the visuospatial/executive functions of the montreal cognitive assessment in patients with vascular cognitive impairment.

PubMed

Ihara, Masafumi; Okamoto, Yoko; Hase, Yoshiki; Takahashi, Ryosuke

2013-10-01

The Montreal Cognitive Assessment (MoCA) is more suitable than the Mini-Mental State Examination (MMSE) for the detection of vascular cognitive impairment. In this study, we performed a correlation analysis of MoCA/MMSE scores with daily physical activity in patients with subcortical ischemic white matter changes. Ten patients (average 75.9 ± 9.1 years old) with extensive leukoaraiosis detected on magnetic resonance imaging underwent cognitive testing, including the MMSE and the Japanese version of the MoCA (MoCA-J). Physical activity was monitored with the Kenz Lifecorder EX device (Suzuken, Nagoya, Japan) to assess daily physical activity in terms of caloric expenditure, motor activity, number of steps, and walking distance for 6 months. Correlations of individual physical activity with total and subscale scores of MMSE/MoCA-J or 6-month interval change of MoCA-J scores were assessed. The total or subscale scores of the MMSE did not correlate with any parameters of physical activity. However, the mean number of steps and walking distance significantly correlated with the total MoCA-J scores (r = .67 and .64, respectively) and its visuospatial/executive subscores (r = .66 and .66, respectively). The mean interval change of MoCA-J was + .6; those who improved number of steps (n = 4; 80.5 ± 3.0 years of age) had significantly preserved MoCA-J scores compared to those who did not (n = 6; 73.0 ± 11.6 years of age; +2.0 versus - .3; P = .016). These results suggest that MoCA is useful to detect a biologically determined specific relationship between physical activity and executive function. In addition, physical exercise, such as walking, may help enhance cognitive function in patients with vascular cognitive impairment of subcortical origin. Copyright © 2013 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Cognitive Assessment of Patients With Alzheimer's Disease by Telemedicine: Pilot Study

PubMed Central

Carotenuto, Anna; Rea, Raffaele; Ricci, Giovanna; Fasanaro, Angiola Maria; Amenta, Francesco

2018-01-01

Background Approximately 46.8 million people are living with dementia worldwide and their number will grow in the next years. Any potential treatment should be administered as early as possible because it is important to provide an early cognitive assessment and to regularly monitor the mental function of patients. Information and communication technologies can be helpful to reach and follow patients without displacing them, but there may be doubts about the reliability of cognitive tests performed by telemedicine. Objective The purpose of this study was to evaluate the reliability of the Mini Mental State Examination (MMSE) and the Alzheimer’s Disease Assessment Scale cognitive subscale (ADAS-cog) tests administered in hospital by videoconference to patients with mild to moderate Alzheimer's disease. Methods The tests were administered to 28 Alzheimer's disease outpatients (8 male, mean age 73.88, SD 7.45 years; 20 female mean age 76.00, SD 5.40 years) recruited and followed in the Alzheimer’s Unit of the A Cardarelli National Hospital (Naples, Italy) at baseline and after 6, 12, 18, and 24 months of observation. Patients were evaluated first face-to-face by a psychologist and then, after 2 weeks, by another psychologist via videoconference in hospital. Results This study showed no differences in the MMSE and ADAS-cog scores when the tests were administered face-to-face or by videoconference, except in patients with more pronounced cognitive deficits (MMSE<17), in which the assessment via videoconference overestimated the cognitive impairment (face to face, MMSE mean 13.9, SD 4.9 and ADAS-cog mean 9.0, SD 3.8; videoconference, MMSE mean 42.8, SD 12.5 and ADAS-cog mean 56.9, SD 5.5). Conclusions We found that videoconferencing is a reliable approach to document cognitive stability or decline, and to measure treatment effects in patients with mild to moderate dementia. A more extended study is needed to confirm these results. PMID:29752254

The temporal limits of cognitive change from music therapy in elderly persons with dementia or dementia-like cognitive impairment: a randomized controlled trial.

PubMed

Bruer, Robert A; Spitznagel, Edward; Cloninger, C Robert

2007-01-01

This study explored the temporal limits of cognitive change from an intention-to-treat with group music therapy. Elderly cognitively-impaired psychiatric inpatients (N = 28) participated in an 8-week randomized control trial using a crossover design. Once a week, subjects were assigned either to music therapy or a control treatment (age-appropriate movie). The Mini-Mental State Exam (MMSE) assessed cognition 3 times every week: prior to the intervention, immediately after the mid-afternoon intervention, and the morning following the intervention. Comparisons between conditions included weekly changes in individual subject's MMSE scores from weekly baseline to both the 2 follow-ups and the following week's baseline. Significant next morning improvements in MMSE scores were found within intent-to-treat music therapy cases as compared to control cases. While all the subjects in this study were cognitively impaired, only 17 had been formally diagnosed with dementia. Based on a Cochrane Collaboration suggestion that music therapy studies within geriatric populations look specifically at the treatment of dementia, a final generalized estimating equation model considered only the change within the 17 dementia-diagnosed subjects. Immediately after the intervention, MMSE scores in the dementia-diagnosed subjects assigned to music therapy improved 2.00 points compared to the dementia-diagnosed subjects assigned to the control group (Z = 1.99, p < .05). Next-day MMSE test scores in the dementia-diagnosed subjects assigned to music therapy showed average improvements of 3.69 points compared to the control subjects (Z = 3.38, p < .001). By the following week, no significant cognitive differences remained between the two groups. It was concluded that a reasonable music therapy intervention facilitated by a trained and accredited music therapist significantly improved next-morning cognitive functioning among dementia patients. With many music therapists working in geriatric settings, more research is justified to both replicate this study and provide better guidance into the effective use of music therapy in the treatment of dementia.

Inter-track interference mitigation with two-dimensional variable equalizer for bit patterned media recording

NASA Astrophysics Data System (ADS)

Wang, Yao; Vijaya Kumar, B. V. K.

2017-05-01

The increased track density in bit patterned media recording (BPMR) causes increased inter-track interference (ITI), which degrades the bit error rate (BER) performance. In order to mitigate the effect of the ITI, signals from multiple tracks can be equalized by a 2D equalizer with 1D target. Usually, the 2D fixed equalizer coefficients are obtained by using a pseudo-random bit sequence (PRBS) for training. In this study, a 2D variable equalizer is proposed, where various sets of 2D equalizer coefficients are predetermined and stored for different ITI patterns besides the usual PRBS training. For data detection, as the ITI patterns are unknown in the first global iteration, the main and adjacent tracks are equalized with the conventional 2D fixed equalizer, detected with Bahl-Cocke-Jelinek-Raviv (BCJR) detector and decoded with low-density parity-check (LDPC) decoder. Then using the estimated bit information from main and adjacent tracks, the ITI pattern for each island of the main track can be estimated and the corresponding 2D variable equalizers are used to better equalize the bits on the main track. This process is executed iteratively by feeding back the main track information. Simulation results indicate that for both single-track and two-track detection, the proposed 2D variable equalizer can achieve better BER and frame error rate (FER) compared to that with the 2D fixed equalizer.

Decline in cognitive function and risk of elder self-neglect: finding from the Chicago Health Aging Project.

PubMed

Dong, XinQi; Simon, Melissa A; Wilson, Robert S; Mendes de Leon, Carlos F; Rajan, K Bharat; Evans, Denis A

2010-12-01

To examine the longitudinal association between decline in cognitive function and risk of elder self-neglect in a community-dwelling population. Prospective population-based study. Geographically defined community in Chicago. Community-dwelling subjects reported to the social services agency from 1993 to 2005 for self-neglect who also participated in the Chicago Health Aging Project (CHAP). Of the 5,519 participants in CHAP, 1,017 were reported to social services agency for suspected elder self-neglect from 1993 to 2005. Social services agency identified reported elder self-neglect. The primary predictor was decline in cognitive function assessed using the Mini-Mental State Examination (MMSE), the Symbol Digit Modalities Test (Executive Function), and immediate and delayed recall of the East Boston Memory Test (Episodic Memory). An index of global cognitive function scores was derived by averaging z-scores of all tests. Outcome of interest was elder self-neglect. Logistic and linear regression models were used to assess these longitudinal associations. After adjusting for potential confounding factors, decline in global cognitive function, MMSE score, and episodic memory were not independently associated with greater risk of reported and confirmed elder self-neglect. Decline in executive function was associated with greater risk of reported and confirmed elder self-neglect. Decline in global cognitive function was associated with greater risk of greater self-neglect severity (parameter estimate=0.76, standard error=0.31, P=.01). Decline in executive function was associated with risk of reported and confirmed elder self-neglect. Decline in global cognitive function was associated with risk of greater self-neglect severity. © 2010, Copyright the Authors. Journal compilation © 2010, The American Geriatrics Society.

Mapping correlations between ventricular expansion and CSF amyloid and tau biomarkers in 240 subjects with Alzheimer’s disease, mild cognitive impairment and elderly controls

PubMed Central

Chou, Yi-Yu; Leporé, Natasha; Avedissian, Christina; Madsen, Sarah K.; Parikshak, Neelroop; Hua, Xue; Shaw, Leslie M.; Trojanowski, John Q.; Weiner, Michael W.; Toga, Arthur W.; Thompson, Paul M.

2009-01-01

Automated ventricular mapping with multi-atlas fluid image alignment reveals genetic effects in Alzheimer’s disease, NeuroImage 40(2): 615–630); with this method, we calculated minimal numbers of subjects needed to detect correlations between clinical scores and ventricular maps. We also assessed correlations between emerging CSF biomarkers of Alzheimer’s disease pathology and localizable deficits in the brain, in 80 AD, 80 mild cognitive impairment (MCI), and 80 healthy controls from the Alzheimer’s Disease Neuroimaging Initiative. Six expertly segmented images and their embedded parametric mesh surfaces were fluidly registered to each brain; segmentations were averaged within subjects to reduce errors. Surface-based statistical maps revealed powerful correlations between surface morphology and 4 variables: (1) diagnosis, (2) depression severity, (3) cognitive function at baseline, and (4) future cognitive decline over the following year. Cognitive function was assessed using the mini-mental state exam (MMSE), global and sum-of-boxes clinical dementia rating (CDR) scores, at baseline and 1-year follow-up. Lower CSF Aβ1–42 protein levels, a biomarker of AD pathology assessed in 138 of the 240 subjects, were correlated with lateral ventricular expansion. Using false discovery rate (FDR) methods, 40 and 120 subjects, respectively, were needed to discriminate AD and MCI from normal groups. 120 subjects were required to detect correlations between ventricular enlargement and MMSE, global CDR, sum-of-boxes CDR and clinical depression scores. Ventricular expansion maps correlate with pathological and cognitive measures in AD, and may be useful in future imaging-based clinical trials. PMID:19236926

Feedforward Equalizers for MDM-WDM in Multimode Fiber Interconnects

NASA Astrophysics Data System (ADS)

Masunda, Tendai; Amphawan, Angela

2018-04-01

In this paper, we present new tap configurations of a feedforward equalizer to mitigate mode coupling in a 60-Gbps 18-channel mode-wavelength division multiplexing system in a 2.5-km-long multimode fiber. The performance of the equalization is measured through analyses on eye diagrams, power coupling coefficients and bit-error rates.

Bayesian estimation of the discrete coefficient of determination.

PubMed

Chen, Ting; Braga-Neto, Ulisses M

2016-12-01

The discrete coefficient of determination (CoD) measures the nonlinear interaction between discrete predictor and target variables and has had far-reaching applications in Genomic Signal Processing. Previous work has addressed the inference of the discrete CoD using classical parametric and nonparametric approaches. In this paper, we introduce a Bayesian framework for the inference of the discrete CoD. We derive analytically the optimal minimum mean-square error (MMSE) CoD estimator, as well as a CoD estimator based on the Optimal Bayesian Predictor (OBP). For the latter estimator, exact expressions for its bias, variance, and root-mean-square (RMS) are given. The accuracy of both Bayesian CoD estimators with non-informative and informative priors, under fixed or random parameters, is studied via analytical and numerical approaches. We also demonstrate the application of the proposed Bayesian approach in the inference of gene regulatory networks, using gene-expression data from a previously published study on metastatic melanoma.

Measuring the Utility of a Cyber Incident Mission Impact Assessment (CIMIA) Process for Mission Assurance

DTIC Science & Technology

2011-03-01

1.179 1 22 .289 POP-UP .000 1 22 .991 Tests the null hypothesis that the error variance of the dependent variable is equal across groups. a. Design ...POP-UP 2.104 1 22 .161 Tests the null hypothesis that the error variance of the dependent variable is equal across groups. a. Design : Intercept... design also limited the number of intended treatments. The experimental design originally was suppose to test all three adverse events that threaten

General model for the pointing error analysis of Risley-prism system based on ray direction deviation in light refraction

NASA Astrophysics Data System (ADS)

Zhang, Hao; Yuan, Yan; Su, Lijuan; Huang, Fengzhen; Bai, Qing

2016-09-01

The Risley-prism-based light beam steering apparatus delivers superior pointing accuracy and it is used in imaging LIDAR and imaging microscopes. A general model for pointing error analysis of the Risley prisms is proposed in this paper, based on ray direction deviation in light refraction. This model captures incident beam deviation, assembly deflections, and prism rotational error. We derive the transmission matrixes of the model firstly. Then, the independent and cumulative effects of different errors are analyzed through this model. Accuracy study of the model shows that the prediction deviation of pointing error for different error is less than 4.1×10-5° when the error amplitude is 0.1°. Detailed analyses of errors indicate that different error sources affect the pointing accuracy to varying degree, and the major error source is the incident beam deviation. The prism tilting has a relative big effect on the pointing accuracy when prism tilts in the principal section. The cumulative effect analyses of multiple errors represent that the pointing error can be reduced by tuning the bearing tilting in the same direction. The cumulative effect of rotational error is relative big when the difference of these two prism rotational angles equals 0 or π, while it is relative small when the difference equals π/2. The novelty of these results suggests that our analysis can help to uncover the error distribution and aid in measurement calibration of Risley-prism systems.

Performance of the Automated Neuropsychological Assessment Metrics (ANAM) in detecting cognitive impairment in heart failure patients.

PubMed

Xie, Susan S; Goldstein, Carly M; Gathright, Emily C; Gunstad, John; Dolansky, Mary A; Redle, Joseph; Hughes, Joel W

2015-01-01

Evaluate capacity of the Automated Neuropsychological Assessment Metrics (ANAM) to detect cognitive impairment (CI) in heart failure (HF) patients. CI is a key prognostic marker in HF. Though the most widely used cognitive screen in HF, the Mini-Mental State Examination (MMSE) is insufficiently sensitive. The ANAM has demonstrated sensitivity to cognitive domains affected by HF, but has not been assessed in this population. Investigators administered the ANAM and MMSE to 57 HF patients, compared against a composite model of cognitive function. ANAM efficiency (p < .05) and accuracy scores (p < .001) successfully differentiated CI and non-CI. ANAM efficiency and accuracy scores classified 97.7% and 93.0% of non-CI patients, and 14.3% and 21.4% with CI, respectively. The ANAM is more effective than the MMSE for detecting CI, but further research is needed to develop a more optimal cognitive screen for routine use in HF patients. Copyright © 2015 Elsevier Inc. All rights reserved.

Payload specialist station study: Volume 2, part 3: Program analysis and planning for phase C/D

NASA Technical Reports Server (NTRS)

1976-01-01

The controls and displays (C&D) required at the Orbiter aft-flight deck (AFD) and the core C&D required at the Payload Specialist Station (PSS) are identified in this document. The AFD C&D Concept consists of a multifunction display system (MFDS) and elements of multiuse mission support equipment (MMSE). The MFDS consists of two CRTs, a display electronics unit (DEU), and a keyboard. The MMSE consists of a manual pointing controller (MPC), five digit numeric displays, 10 character alphanumeric legends, event timers, analog meters, rotary and toggle switches. The MMSE may be hardwired to the experiment, or interface with a data bus at the PSS for signal processing. The MFDS has video capability, with alphanumeric and graphic overlay features, on one CRT and alphanumeric and graphic (tricolor) capability on a second CRT. The DEU will have the capability to communicate, via redundant data buses, with both the spacelab experiment and subsystem computers.

Cognitive impairment in patients with fibromyalgia syndrome as assessed by the mini-mental state examination.

PubMed

Rodríguez-Andreu, Jose; Ibáñez-Bosch, Rosario; Portero-Vázquez, Amparo; Masramon, Xavier; Rejas, Javier; Gálvez, Rafael

2009-12-21

This study evaluated the frequency of cognitive impairment in patients with Fibromyalgia syndrome (FMS) using the Mini Mental State Examination (MMSE). We analyzed baseline data from all 46 patients with FMS and 92 age- and sex-matched controls per diagnosis of neuropathic (NeP) or mixed pain (MP) selected from a larger prospective study. FMS had a slight but statistically significant lower score in the adjusted MMSE score (26.9; 95% CI 26.7-27.1) than either NeP (27.3; 95% CI 27.2-27.4) or MP (27.3; 27.2-27.5). The percentage of patients with congnitive impairment (adjusted MMSE

Predictors of driving safety in early Alzheimer disease

PubMed Central

Dawson, J D.; Anderson, S W.; Uc, E Y.; Dastrup, E; Rizzo, M

2009-01-01

Objective: To measure the association of cognition, visual perception, and motor function with driving safety in Alzheimer disease (AD). Methods: Forty drivers with probable early AD (mean Mini-Mental State Examination score 26.5) and 115 elderly drivers without neurologic disease underwent a battery of cognitive, visual, and motor tests, and drove a standardized 35-mile route in urban and rural settings in an instrumented vehicle. A composite cognitive score (COGSTAT) was calculated for each subject based on eight neuropsychological tests. Driving safety errors were noted and classified by a driving expert based on video review. Results: Drivers with AD committed an average of 42.0 safety errors/drive (SD = 12.8), compared to an average of 33.2 (SD = 12.2) for drivers without AD (p < 0.0001); the most common errors were lane violations. Increased age was predictive of errors, with a mean of 2.3 more errors per drive observed for each 5-year age increment. After adjustment for age and gender, COGSTAT was a significant predictor of safety errors in subjects with AD, with a 4.1 increase in safety errors observed for a 1 SD decrease in cognitive function. Significant increases in safety errors were also found in subjects with AD with poorer scores on Benton Visual Retention Test, Complex Figure Test-Copy, Trail Making Subtest-A, and the Functional Reach Test. Conclusion: Drivers with Alzheimer disease (AD) exhibit a range of performance on tests of cognition, vision, and motor skills. Since these tests provide additional predictive value of driving performance beyond diagnosis alone, clinicians may use these tests to help predict whether a patient with AD can safely operate a motor vehicle. GLOSSARY AD = Alzheimer disease; AVLT = Auditory Verbal Learning Test; Blocks = Block Design subtest; BVRT = Benton Visual Retention Test; CFT = Complex Figure Test; CI = confidence interval; COWA = Controlled Oral Word Association; CS = contrast sensitivity; FVA = far visual acuity; JLO = Judgment of Line Orientation; MCI = mild cognitive impairment; MMSE = Mini-Mental State Examination; NVA = near visual acuity; SFM = structure from motion; TMT = Trail-Making Test; UFOV = Useful Field of View. PMID:19204261

Comparative Diagnostic Accuracy of the ACE-III, MIS, MMSE, MoCA, and RUDAS for Screening of Alzheimer Disease.

PubMed

Matías-Guiu, Jordi A; Valles-Salgado, María; Rognoni, Teresa; Hamre-Gil, Frank; Moreno-Ramos, Teresa; Matías-Guiu, Jorge

2017-01-01

Our aim was to evaluate and compare the diagnostic properties of 5 screening tests for the diagnosis of mild Alzheimer disease (AD). We conducted a prospective and cross-sectional study of 92 patients with mild AD and of 68 healthy controls from our Department of Neurology. The diagnostic properties of the following tests were compared: Mini-Mental State Examination (MMSE), Addenbrooke's Cognitive Examination III (ACE-III), Memory Impairment Screen (MIS), Montreal Cognitive Assessment (MoCA), and Rowland Universal Dementia Assessment Scale (RUDAS). All tests yielded high diagnostic accuracy, with the ACE-III achieving the best diagnostic properties. The area under the curve was 0.897 for the ACE-III, 0.889 for the RUDAS, 0.874 for the MMSE, 0.866 for the MIS, and 0.856 for the MoCA. The Mini-ACE score from the ACE-III showed the highest diagnostic capacity (area under the curve 0.939). Memory scores of the ACE-III and of the RUDAS showed a better diagnostic accuracy than those of the MMSE and of the MoCA. All tests, especially the ACE-III, conveyed a higher diagnostic accuracy in patients with full primary education than in the less educated group. Implementing normative data improved the diagnostic accuracy of the ACE-III but not that of the other tests. The ACE-III achieved the highest diagnostic accuracy. This better discrimination was more evident in the more educated group. © 2017 S. Karger AG, Basel.

A systematic review of cognitive decline in dementia with Lewy bodies versus Alzheimer’s disease

PubMed Central

2014-01-01

Introduction The aim of this review was to investigate whether there is a faster cognitive decline in dementia with Lewy bodies (DLB) than in Alzheimer’s disease (AD) over time. Methods PsycINFO and Medline were searched from 1946 to February 2013. A quality rating from 1 to 15 (best) was applied to the included studies. A quantitative meta-analysis was done on studies with mini mental state examination (MMSE) as the outcome measure. Results A total of 18 studies were included. Of these, six (36%) reported significant differences in the rate of cognitive decline. Three studies reported a faster cognitive decline on MMSE in patients with mixed DLB and AD compared to pure forms, whereas two studies reported a faster decline on delayed recall and recognition in AD and one in DLB on verbal fluency. Mean quality scores for studies that did or did not differ were not significantly different. Six studies reported MMSE scores and were included in the meta-analysis, which showed no significant difference in annual decline on MMSE between DLB (mean 3.4) and AD (mean 3.3). Conclusions Our findings do not support the hypothesis of a faster rate of cognitive decline in DLB compared to AD. Future studies should apply recent diagnostic criteria, as well as extensive diagnostic evaluation and ideally autopsy diagnosis. Studies with large enough samples, detailed cognitive tests, at least two years follow up and multivariate statistical analysis are also needed. PMID:25478024

Electroencephalographic characteristics of Iranian schizophrenia patients.

PubMed

Chaychi, Irman; Foroughipour, Mohsen; Haghir, Hossein; Talaei, Ali; Chaichi, Ashkan

2015-12-01

Schizophrenia is a prevalent psychiatric disease with heterogeneous causes that is diagnosed based on history and mental status examination. Applied electrophysiology is a non-invasive method to investigate the function of the involved brain areas. In a previously understudied population, we examined acute phase electroencephalography (EEG) records along with pertinent Positive and Negative Syndrome Scale (PANSS) and Mini Mental State Examination (MMSE) scores for each patient. Sixty-four hospitalized patients diagnosed to have schizophrenia in Ebn-e-Sina Hospital were included in this study. PANSS and MMSE were completed and EEG tracings for every patient were recorded. Also, EEG tracings were recorded for 64 matched individuals of the control group. Although the predominant wave pattern in both patients and controls was alpha, theta waves were almost exclusively found in eight (12.5 %) patients with schizophrenia. Pathological waves in schizophrenia patients were exclusively found in the frontal brain region, while identified pathological waves in controls were limited to the temporal region. No specific EEG finding supported laterality in schizophrenia patients. PANSS and MMSE scores were significantly correlated with specific EEG parameters (all P values <0.04). Patients with schizophrenia demonstrate specific EEG patterns and show a clear correlation between EEG parameters and PANSS and MMSE scores. These characteristics are not observed in all patients, which imply that despite an acceptable specificity, they are not applicable for the majority of schizophrenia patients. Any deduction drawn based on EEG and scoring systems is in need of larger studies incorporating more patients and using better functional imaging techniques for the brain.

Correlation between the Quality of Attention and Cognitive Competence with Motor Action in Stroke Patients.

PubMed

Arsic, S; Konstantinovic, Lj; Eminovic, F; Pavlovic, D; Popovic, M B; Arsic, V

2015-01-01

It is considered that cognitive function and attention could affect walking, motion control, and proper conduct during the walk. To determine whether there is a difference in the quality of attention and cognitive ability in stroke patients and patients without neurological damage of similar age and education and to determine whether the connection of attention and cognition affects motor skills, the sample consisted of 50 stroke patients tested with hemiparesis, involved in the process of rehabilitation, and 50 persons, randomly chosen, without neurological damage. The survey used the following tests: Trail Making (TMT A B) test for assessing the flexibility of attention; Mini-Mental State Examination (MMSE) for cognitive status; Functional Ambulation Category (FAC) test to assess the functional status and parameters of walk: speed, frequency, and length of stride; STEP test for assessing the precision of movement and balance. With stroke patients, relationship between age and performance on the MMSE test was marginally significant. The ratio of performance to TMT A B test and years does not indicate statistical significance, while statistical significance between the MMSE test performance and education exists. In stroke patients, performance on MMSE test is correlated with the frequency and length of stride walk. The quality of cognitive function and attention is associated with motor skills but differs in stroke patients and people without neurological damage of similar age. The significance of this correlation can supplement research in neurorehabilitation, improve the quality of medical rehabilitation, and contribute to efficient recovery of these patients.

Uncertainties in the cluster-cluster correlation function

NASA Astrophysics Data System (ADS)

Ling, E. N.; Frenk, C. S.; Barrow, J. D.

1986-12-01

The bootstrap resampling technique is applied to estimate sampling errors and significance levels of the two-point correlation functions determined for a subset of the CfA redshift survey of galaxies and a redshift sample of 104 Abell clusters. The angular correlation function for a sample of 1664 Abell clusters is also calculated. The standard errors in xi(r) for the Abell data are found to be considerably larger than quoted 'Poisson errors'. The best estimate for the ratio of the correlation length of Abell clusters (richness class R greater than or equal to 1, distance class D less than or equal to 4) to that of CfA galaxies is 4.2 + 1.4 or - 1.0 (68 percentile error). The enhancement of cluster clustering over galaxy clustering is statistically significant in the presence of resampling errors. The uncertainties found do not include the effects of possible systematic biases in the galaxy and cluster catalogs and could be regarded as lower bounds on the true uncertainty range.

Kalman Filtering Approach to Blind Equalization

DTIC Science & Technology

1993-12-01

NAVAL POSTGRADUATE SCHOOL Monterey, California •GR AD13 DTIC 94-07381 AR 0C199 THESIS S 0 LECTE4u KALMAN FILTERING APPROACH TO BLIND EQUALIZATION by...FILTERING APPROACH 5. FUNDING NUMBERS TO BLIND EQUALIZATION S. AUTHOR(S) Mehmet Kutlu 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) S...which introduces errors due to intersymbol interference. The solution to this problem is provided by equalizers which use a training sequence to adapt to

The nearest neighbor and the bayes error rates.

PubMed

Loizou, G; Maybank, S J

1987-02-01

The (k, l) nearest neighbor method of pattern classification is compared to the Bayes method. If the two acceptance rates are equal then the asymptotic error rates satisfy the inequalities Ek,l + 1 ¿ E*(¿) ¿ Ek,l dE*(¿), where d is a function of k, l, and the number of pattern classes, and ¿ is the reject threshold for the Bayes method. An explicit expression for d is given which is optimal in the sense that for some probability distributions Ek,l and dE* (¿) are equal.

Eighth Grade Students' Reading Responses to Encoded Inflectional, Syntactic, Grammatical and Semantic Errors.

ERIC Educational Resources Information Center

Williamson, Leon E.; And Others

A study investigated the reading responses of 60 eighth grade students to encoded inflectional, syntactic, grammatical, and semantic errors. The students were equally divided into three categories based on grade level reading competency and given three Aesopian fables to read. The text of the fables contained the following errors: (1) words to…

Fusing Bluetooth Beacon Data with Wi-Fi Radiomaps for Improved Indoor Localization

PubMed Central

Kanaris, Loizos; Kokkinis, Akis; Liotta, Antonio; Stavrou, Stavros

2017-01-01

Indoor user localization and tracking are instrumental to a broad range of services and applications in the Internet of Things (IoT) and particularly in Body Sensor Networks (BSN) and Ambient Assisted Living (AAL) scenarios. Due to the widespread availability of IEEE 802.11, many localization platforms have been proposed, based on the Wi-Fi Received Signal Strength (RSS) indicator, using algorithms such as K-Nearest Neighbour (KNN), Maximum A Posteriori (MAP) and Minimum Mean Square Error (MMSE). In this paper, we introduce a hybrid method that combines the simplicity (and low cost) of Bluetooth Low Energy (BLE) and the popular 802.11 infrastructure, to improve the accuracy of indoor localization platforms. Building on KNN, we propose a new positioning algorithm (dubbed i-KNN) which is able to filter the initial fingerprint dataset (i.e., the radiomap), after considering the proximity of RSS fingerprints with respect to the BLE devices. In this way, i-KNN provides an optimised small subset of possible user locations, based on which it finally estimates the user position. The proposed methodology achieves fast positioning estimation due to the utilization of a fragment of the initial fingerprint dataset, while at the same time improves positioning accuracy by minimizing any calculation errors. PMID:28394268

Fusing Bluetooth Beacon Data with Wi-Fi Radiomaps for Improved Indoor Localization.

PubMed

Kanaris, Loizos; Kokkinis, Akis; Liotta, Antonio; Stavrou, Stavros

2017-04-10

Indoor user localization and tracking are instrumental to a broad range of services and applications in the Internet of Things (IoT) and particularly in Body Sensor Networks (BSN) and Ambient Assisted Living (AAL) scenarios. Due to the widespread availability of IEEE 802.11, many localization platforms have been proposed, based on the Wi-Fi Received Signal Strength (RSS) indicator, using algorithms such as K -Nearest Neighbour (KNN), Maximum A Posteriori (MAP) and Minimum Mean Square Error (MMSE). In this paper, we introduce a hybrid method that combines the simplicity (and low cost) of Bluetooth Low Energy (BLE) and the popular 802.11 infrastructure, to improve the accuracy of indoor localization platforms. Building on KNN, we propose a new positioning algorithm (dubbed i-KNN) which is able to filter the initial fingerprint dataset (i.e., the radiomap), after considering the proximity of RSS fingerprints with respect to the BLE devices. In this way, i-KNN provides an optimised small subset of possible user locations, based on which it finally estimates the user position. The proposed methodology achieves fast positioning estimation due to the utilization of a fragment of the initial fingerprint dataset, while at the same time improves positioning accuracy by minimizing any calculation errors.

Cognitive Assessment of Patients With Alzheimer's Disease by Telemedicine: Pilot Study.

PubMed

Carotenuto, Anna; Rea, Raffaele; Traini, Enea; Ricci, Giovanna; Fasanaro, Angiola Maria; Amenta, Francesco

2018-05-11

Approximately 46.8 million people are living with dementia worldwide and their number will grow in the next years. Any potential treatment should be administered as early as possible because it is important to provide an early cognitive assessment and to regularly monitor the mental function of patients. Information and communication technologies can be helpful to reach and follow patients without displacing them, but there may be doubts about the reliability of cognitive tests performed by telemedicine. The purpose of this study was to evaluate the reliability of the Mini Mental State Examination (MMSE) and the Alzheimer's Disease Assessment Scale cognitive subscale (ADAS-cog) tests administered in hospital by videoconference to patients with mild to moderate Alzheimer's disease. The tests were administered to 28 Alzheimer's disease outpatients (8 male, mean age 73.88, SD 7.45 years; 20 female mean age 76.00, SD 5.40 years) recruited and followed in the Alzheimer's Unit of the A Cardarelli National Hospital (Naples, Italy) at baseline and after 6, 12, 18, and 24 months of observation. Patients were evaluated first face-to-face by a psychologist and then, after 2 weeks, by another psychologist via videoconference in hospital. This study showed no differences in the MMSE and ADAS-cog scores when the tests were administered face-to-face or by videoconference, except in patients with more pronounced cognitive deficits (MMSE<17), in which the assessment via videoconference overestimated the cognitive impairment (face to face, MMSE mean 13.9, SD 4.9 and ADAS-cog mean 9.0, SD 3.8; videoconference, MMSE mean 42.8, SD 12.5 and ADAS-cog mean 56.9, SD 5.5). We found that videoconferencing is a reliable approach to document cognitive stability or decline, and to measure treatment effects in patients with mild to moderate dementia. A more extended study is needed to confirm these results. ©Anna Carotenuto, Raffaele Rea, Enea Traini, Giovanna Ricci, Angiola Maria Fasanaro, Francesco Amenta. Originally published in JMIR Mental Health (http://mental.jmir.org), 11.05.2018.

Telomere Length, Long-Term Black Carbon Exposure, and Cognitive Function in a Cohort of Older Men: The VA Normative Aging Study.

PubMed

Colicino, Elena; Wilson, Ander; Frisardi, Maria Chiara; Prada, Diddier; Power, Melinda C; Hoxha, Mirjam; Dioni, Laura; Spiro, Avron; Vokonas, Pantel S; Weisskopf, Marc G; Schwartz, Joel D; Baccarelli, Andrea A

2017-01-01

Long-term air pollution exposure has been associated with age-related cognitive impairment, possibly because of enhanced inflammation. Leukocytes with longer telomere length (TL) are more responsive to inflammatory stimuli, yet TL has not been evaluated in relation to air pollution and cognition. We assessed whether TL modifies the association of 1-year exposure to black carbon (BC), a marker of traffic-related air pollution, with cognitive function in older men, and we examined whether this modification is independent of age and of C-reactive protein (CRP), a marker of inflammation. Between 1999 and 2007, we conducted 1-3 cognitive examinations of 428 older men in the Veterans Affairs (VA) Normative Aging Study. We used covariate-adjusted repeated-measure logistic regression to estimate associations of 1-year BC exposure with relative odds of being a low scorer (≤ 25) on the Mini-Mental State Examination (MMSE), which is a proxy of poor cognition. Confounders included age, CRP, and lifestyle and sociodemographic factors. Each doubling in BC level was associated with 1.57 (95% CI: 1.20, 2.05) times higher odds of low MMSE scores. The BC-MMSE association was greater only among individuals with longer blood TL (5th quintile) (OR = 3.23; 95% CI: 1.37, 7.59; p = 0.04 for BC-by-TL-interaction). TL and CRP were associated neither with each other nor with MMSE. However, CRP modified the BC-MMSE relationship, with stronger associations only at higher CRP (5th quintile) and reference TL level (1st quintile) (OR = 2.68; 95% CI: 1.06, 6.79; p = 0.04 for BC-by-CRP-interaction). TL and CRP levels may help predict the impact of BC exposure on cognitive function in older men. Citation: Colicino E, Wilson A, Frisardi MC, Prada D, Power MC, Hoxha M, Dioni L, Spiro A III, Vokonas PS, Weisskopf MG, Schwartz JD, Baccarelli AA. 2017. Telomere length, long-term black carbon exposure, and cognitive function in a cohort of older men: the VA Normative Aging Study. Environ Health Perspect 125:76-81; http://dx.doi.org/10.1289/EHP241.

Depression and dementia in Parkinson's disease.

PubMed

Sinanović, Osman; Hudić, Josip; Zukić, Sanela; Kapidžić, Almasa; Zonić, Lejla; Vidović, Mirjana

2015-03-01

Parkinson's disease (PD) is a neurodegenerative disorder causing not only motor dysfunction but also cognitive, psychiatric, autonomic and sensory disturbances. Depression is the most common psychiatric disturbance identified in patients with PD and has been shown to be more common in PD than in other chronic and disabling disorders, occurring in approximately 40% of PD patients. However, the prevalence and clinical features associated with depression in PD remain controversial. Dementia is increasingly recognized as a symptom associated with idiopathic PD, and is found in up to 40% of all patients suffering from that condition. The aim of this study was to estimate the prevalence of depressive and dementia symptoms in PD patients. The study included 35 consecutive patients with PD, 13 (37.4%) male and 22 (62.6%) female (mean age 62.9 ± 11.0, range 36-85 years), mean duration of disease 4.7 ± 2.9 (range 1-10) years, hospitalized during one year at Clinical Department of Neurology, Tuzla University Clinical Center, Tuzla, Bosnia and Herzegovina. The Mini Mental State Examination (MMSE) was used for assessment of cognitive deterioration and Beck Depression Inventory (BDI) for depression. Computerized tomography was performed in all patients. According to BDI scale, depressive symptoms were present in all 35 PD patients: minimal in 4 (11.4%), low in 7 (20%), moderate in 8 (22.8%), severe in 9 (25.4%) and extreme in 7 (20%) patients. On MMSE scale, 9 (25.4%) patients were free from cognitive deterioration and 26 (74.6%) patients had moderate to severe deterioration, but 21 (60%) patients (7 (33.33%) male and 14 (66.66%) female) had symptoms of dementia (MMSE score ≤ 23). Using MMSE scale, 8 (22.8%) patients were free from dementia and 27 (77.2%) patients had some cognitive deterioration. Very mild symptoms of dementia were found in 6 (25.9%) and overt features of dementia in 21 (74.1%) PD patients. So, out of 35 PD study patients, 21 (60%) (7 (33.3%) male and 14 (66.7%) female) had symptoms of dementia (MMSE score ≤ 23). In conclusion, depressive and dementia symptoms are common in PD patients.

Does cognitive/physical screening in an outpatient setting predict institutionalization after hip fracture?

PubMed

Hongisto, Markus T; Nuotio, Maria; Luukkaala, Tiina; Väistö, Olli; Pihlajamäki, Harri K

2016-10-22

Institutionalization after hip fracture is a socio-economical burden. We examined the predictive value of Instrumental Activities of Daily Living (IADL) and Mini Mental State Examination (MMSE) for institutionalization after hip fracture to identify patients at risk for institutionalization. Fragility hip fracture patients ≥65 years of age (n = 584) were comprehensively examined at a geriatric outpatient clinic 4 to 6 months after surgery and followed 1 year postoperatively. A telephone interview with a structured inquiry was performed at 1, 4, and 12 months after hip fracture. Age-adjusted univariate logistic regression analysis revealed that IADL and MMSE scores measured at the outpatient clinic were significantly associated with living arrangements 1 year after hip fracture. Multivariate logistic regression analysis established that institutionalization 1 year after hip fracture was significantly predicted by institutionalization at 4 months (odds ratio [OR] 16.26, 95 % confidence interval [CI] 7.37-35.86), IADL <5 (OR 12.96, 95 % CI 1.62-103.9), and MMSE <20 (OR 4.19, 95 % CI 1.82-9.66). A cut-off value of 5 was established for IADL with 100 % (95 % CI 96 %-100 %) sensitivity and 38 % (95 % CI 33 %-43 %) specificity and for MMSE, a cut-off value of 20 had 83 % (95 % CI 74 %-91 %) sensitivity and 65 % (95 % CI 60 %-70 %) specificity for institutionalization. During the time period from 4 to 12 months, 66 (11 %) patients changed living arrangements, and 36 (55 %) of these patients required more supportive accommodations. IADL and MMSE scores obtained 4 to 6 months after hospital discharge may be applicable for predicting institutionalization among fragility hip fracture patients ≥65 years of age at 1 year after hip fracture. An IADL score of ≥5 predicted the ability to remain in the community. Changes in living arrangements also often occur after 4 months.

[Relationship between status of physical and mental function and quality of life among the elderly people admitted from long-term care insurance].

PubMed

Kim, Hyeong Seon; Bae, Nam Kyou; Kwon, In Sun; Cho, Young Chae

2010-07-01

This study was performed to determine the levels of quality of life (QOL) according to the grade of long-term care service for the elderly people who were admitted from long-term care insurance, and to reveal its association with the physical and mental functioning such as the Activity of Daily Living (ADL), the Instrumental Activity of Daily Living (IADL), the Center for Epidemiologic Studies Depression Scale (CES-D), and the Mini-Mental State Examination-Korean version (MMSE-K). The interviews were performed during the period from March 1 to May 31, 2009, for 958 elderly people in urban and rural areas. The questionnaire items included various indices such as the ADL, IADL, CES-D, and MMSE-K, as independent variables and the index of QOL, as the dependent ones. For statistical analysis, t-tests were used for the mean scores of QOL according to gender and the grade of long-term care services, and Spearman's correlation was used for each variable. The effects of physical and mental functioning for QOL were assessed by covariance structure analysis. The statistical significance was set at p<0.05. The mean scores of QOL among all the subjects was 55.4 ± 15.62 (Grade I: 49.7 ± 14.17, Grade II: 56.8 ± 14.62, Grade III: 59.4 ± 16.36), and it was lower according to the higher grade of long-term care insurance. In terms of the correlation matrix of the QOL and the physical and mental function factors, the QOL showed positive correlation with the ADL, IADL and MMSE-K, while it had negative correlation with depression. On the analysis of covariance, mental functioning (depression and the MMSE-K) had a greater influence on the level of QOL than the physical functioning (ADL and IADL). The level of the QOL in the elderly people who were admitted from long-term care insurance was lower according to higher the grade of long-term care insurance. Also, the mental functioning (depression and MMSE-K) was more influential on the level of the QOL than the physical functioning (ADL and IADL).

Predictive factors for dementia and cognitive impairment among residents living in the veterans' retirement communities in Taiwan: Implications for cognitive health promotion activities.

PubMed

Chen, Liang-Yu; Wu, Yi-Hui; Huang, Chung-Yu; Liu, Li-Kuo; Hwang, An-Chun; Peng, Li-Ning; Lin, Ming-Hsieh; Chen, Liang-Kung

2017-04-01

To identify potentially modifiable risk factors for cognitive decline among veterans' home residents in Taiwan METHODS: The present retrospective cohort study was part of the Veteran Affairs-Comprehensive Geriatric Assessment study that retrieved data of the comprehensive geriatric assessment for 946 residents living at four veterans' homes in Taiwan. The study participants were interviewed every 3-6 months from January 2012 and December 2014. Demographic characteristics,multimorbidity by Charlson's Comorbidities Index, physical function by the Barthel Index, cognition by the Mini-Mental State Examination (MMSE), depression by the five-item Geriatric Depression Scale and nutritional status by the Mini-Nutrition Assessment-Short Form were collected for analysis. A generalized estimating equation model was used after it was adjusted for age, educational level, five-item Geriatric Depression Scale, and problem of communication difficulty to identify potential modifiable risk factors for cognitive decline. The mean age of the participants was 85.7 ± 5.2 years, with a mean follow-up period of 41 ± 21.6 weeks. The prevalence of cognitive impairment (defined by MMSE <24) was 65.6%, whereas 34% of the study participants were positive for depressive symptoms. Approximately one-fifth of the study participants were using psychotropic agents, which was higher among participants with cognitive impairment (23.6% vs 15.6%, P < 0.05) than those without. In the generalized estimating equation model, physical function, nutritional status, depressive symptoms, ex-drinker, multimorbidity and stool incontinence were positively correlated with MMSE score; whereas advanced age, low educational level (<6 years), presence of communication difficulty and use of psychotropic agents were inversely associated with the MMSE score. Physical function and nutritional status were positively associated with the MMSE score, and use of psychotropic agents was negatively correlated with cognitive function. Further intervention study is required to improve the cognitive health of older adults living in the veterans' retirement communities. Geriatr Gerontol Int 2017: 17 (Suppl. 1): 7-13. © 2017 Japan Geriatrics Society.

Determinants of Quality of Life in the Acute Stage Following Stroke

PubMed Central

Jeong, Bo-Ok; Kang, Hee-Ju; Bae, Kyung-Yeol; Kim, Sung-Wan; Shin, Il-Seon; Kim, Joon-Tae; Park, Man-Seok; Cho, Ki-Hyun; Yoon, Jin-Sang

2012-01-01

Objective This study aimed to investigate the factors influence the quality of life (QOL) of survivors of an acute stroke. Methods For 422 stroke patients, assessments were made within two weeks of the index event. QOL was measured using the World Health Organization Quality of Life-Abbreviated form (WHOQOL-BREF), which has four domains related to physical factors, psychological factors, social relationships, and environmental context. Associations of each four WHOQOL-BREF domain score with socio-demographic characteristics (age, sex, education, marital status, religion, and occupation), stroke severity (National Institutes of Health Stroke Scale), physical disability (Barthel Index), cognitive function (Mini-Mental Status Examination: MMSE), grip strength, and psychological distress (Hospital Anxiety and Depression Scale depression and anxiety subscale: HADS-D and HADS-A) were investigated using the linear regression models. Results Higher physical domain scores were independently associated with higher MMSE scores, stronger hand-grip strength, and lower HADS-D and HADS-A scores; higher psychological domain scores were independently associated with higher educational level, higher MMSE scores, and lower HADS-D and HADS-A scores; higher social relationships domain scores were independently associated with lower HADS-D and HADS-A scores; and higher environmental domain scores were independently associated with higher educational level, higher MMSE scores, and lower HADS-D scores. Conclusion Psychological distress and impaired cognitive function were independently associated with lower QOL in patients with acute stroke. However, stroke severity, physical disability and other socio-demographic factors were less significantly associated with QOL. These findings underscore the importance of psychological interventions for improving QOL during the acute phase following stroke. PMID:22707962

Differential effects of enriched environment at work on cognitive decline in old age.

PubMed

Then, Francisca S; Luck, Tobias; Luppa, Melanie; König, Hans-Helmut; Angermeyer, Matthias C; Riedel-Heller, Steffi G

2015-05-26

The aim of the present study was to investigate how different mentally demanding work conditions during the professional life-i.e., enriched environments at work-might influence the rate of cognitive decline in old age. Individuals (n = 1,054) of the Leipzig Longitudinal Study of the Aged, a representative population-based cohort study of individuals aged 75 years and older, underwent cognitive testing via the Mini-Mental State Examination (MMSE) in up to 6 measurement waves. Type and level of mentally demanding work conditions in the participants' former professional life were classified based on the O*NET job descriptor database. In multivariate mixed-model analyses (controlling for sociodemographic and health-related factors), a high level of mentally demanding work tasks stimulating verbal intelligence was significantly associated with a better cognitive functioning at baseline (on average 5 MMSE points higher) as well as a lower rate of cognitive decline (on average 2 MMSE points less) over the 8-year follow-up period compared with a low level. The rate of cognitive decline in old age was also significantly lower (on average 3 MMSE points less) in individuals who had a high level of mentally demanding work tasks stimulating executive functions than those who had a low level. The results suggest that a professional life enriched with work tasks stimulating verbal intelligence and executive functions may help to sustain a good cognitive functioning in old age (75+ years). The findings thus emphasize that today's challenging work conditions may also promote positive health effects. © 2015 American Academy of Neurology.

Exploring the Role of Cognitive Factors in a New Instrument for Elders' Financial Capacity Assessment.

PubMed

Giannouli, Vaitsa; Stamovlasis, Dimitrios; Tsolaki, Magda

2018-01-01

The influence of cognitive factors on financial capacity across the dementia spectrum of cognitive aging, Alzheimer's disease (AD), and mild cognitive impairment (MCI) has been little investigated, while it has not been investigated at all in other types of dementia as well as in extended samples of elders in Greece. The aim of this study is to investigate financial capacity, to develop a tool, test its psychometric properties, validate, and then test the tool in groups of healthy controls compared to elders with dementia, while examining other facets of their cognitive performance. 719 elders from Greece including healthy participants and patients with different types of dementia were examined with Legal Capacity for Property Law Transactions Assessment Scale (LCPLTAS) and a battery of neuropsychological tests concerning various cognitive functions. Significantly different profiles in the scores and subscores of LCPLTAS for all the groups of dementia patients were found, with a general incapacity finding for all the dementia groups including the MCI patients. Logistic regression showed that Mini-Mental State Examination (MMSE), Geriatric Depression Scale, and Trail Making Part B predicted competence on LCPLTAS for the dementia patients. Persons with MCI and dementia had lower financial knowledge scores than those without cognitive impairment, with MMSE scores below 27 suggestive as an indication of financial incapacity. The LCPLTAS provides information for a strong positive correlation with MMSE, while the use both of MMSE and LCPLTAS as adequate measures of financial (in)capacity is discussed for the Greek legal procedures regarding elder guardianship cases.

Decision trees for the analysis of genes involved in Alzheimer's disease pathology.

PubMed

Mestizo Gutiérrez, Sonia L; Herrera Rivero, Marisol; Cruz Ramírez, Nicandro; Hernández, Elena; Aranda-Abreu, Gonzalo E

2014-09-21

Alzheimer's disease (AD) is characterized by a gradual loss of memory, orientation, judgement and language. There is still no cure for this disorder. AD pathogenesis remains fairly unknown and its underlying molecular mechanisms are not yet fully understood. Several studies have shown that the abnormal accumulation of beta-amyloid and tau proteins occurs 10 to 20 years before the onset of symptoms of the disease, so it is extremely important to identify changes in the brain before the first symptoms. We used decision trees to classify 31 individuals (9 healthy controls and 22 AD patients in three different stages of disease) according to the expression of 69 genes previously reported in a meta-analysis, plus the expression levels of APP, APOE, BACE1, NCSTN, PSEN1, PSEN2 and MAPT. We also included in our analysis the MMSE (Mini-Mental State Examination) scores and number of NFT (neurofibrillary tangles). Results allowed us to generate a model of classification values for different AD stages of severity, according to MMSE scores, and achieve the identification of the expression level of protein tau that may possibly determine the onset (incipient stage) of AD. We used decision trees to model the different stages of AD (severe, moderate, incipient and control) based on the meta-analysis of gene expression levels plus MMSE and NFT scores. Both classifiers reported the variable MMSE as most informative, however it we were found that the protein tau also an important role in the onset of AD. Copyright © 2014 Elsevier Ltd. All rights reserved.

Going outdoors and cognitive function among community-dwelling older adults: Moderating role of physical function.

PubMed

Harada, Kazuhiro; Lee, Sangyoon; Park, Hyuntae; Shimada, Hiroyuki; Makizako, Hyuma; Doi, Takehiko; Yoshida, Daisuke; Tsutsumimoto, Kota; Anan, Yuya; Uemura, Kazuki; Suzuki, Takao

2016-01-01

Identifying the risk factors of cognitive impairment is essential for implementing effective prevention strategies for dementia. Previous studies have shown that the frequency of going outdoors is inversely associated with cognitive decline. Little research has examined whether the relationship between going outdoors and cognitive decline varies with physical functioning in older adults. The aim of the present study was to examine the relationship between going outdoors and cognitive function in older adults with and without physical function limitations. The present study analyzed the data of 4450 individuals (aged 65 years or older) who participated in the Obu Study of Health Promotion for the Elderly. The measures were the Mini-Mental State Examination (MMSE), going outdoors (at least once a week or not), self-reported physical function limitations (with or without), and demographic and health-related factors as potential confounders. Analysis of covariance and post-hoc comparisons showed that although going outdoors at least once a week was associated with higher MMSE scores among older adults with limited physical function, it was not significantly associated with the MMSE scores among older adults without limited physical function. Similarly, logistic regression analyses, stratified by physical function, showed a significant association between going outdoors and MMSE (<24 points or not) among older adults with limited physical function. The results show that going outdoors less than once a week is associated with decreased cognitive function among older adults with limited physical function, but it is not associated with cognitive function among older adults without limited physical function. © 2015 Japan Geriatrics Society.

Carotid intima-media thickness and cognitive function in a middle-aged and older adult community: a cross-sectional study.

PubMed

Wang, Anxin; Chen, Guojuan; Su, Zhaoping; Liu, Xiaoxue; Yuan, Xiaodong; Jiang, Ruixuan; Cao, Yibin; Chen, Shuohua; Luo, Yanxia; Guo, Xiuhua; Wu, Shouling; Zhao, Xingquan

2016-10-01

The relationship between atherosclerosis and cognitive function is less well studied in Chinese populations. In addition, the results among middle-aged adults have been mixed. We aimed to investigate the association of atherosclerosis measured by carotid intima-media thickness (CIMT) and cognitive function in middle-aged and older adults from a Chinese community. Participants in the Asymptomatic Polyvascular Abnormalities in Community study (APAC) who had completed the CIMT detection and cognitive function measurements in 2012/2013 were included. Cognitive function was measured using the Mini-Mental State Examination (MMSE). Multivariate linear regression analysis was used to analyze the association between CIMT and MMSE. Then, a stratified analysis was performed separately in middle-aged and older adults. A total of 3227 participants were included in this study (mean age 57.9 years, range 43-93 years); 56.6 % of them were men, 66.0 % were middle-aged adults. After adjusting for potential confounders, larger CIMT was associated with lower MMSE scores, with a 0.75-point decrease in MMSE score for every 1-mm increase in CIMT (β = - 0.75, P = 0.0020). The association remained statistically significant in middle-aged adults (β = - 0.57, P = 0.0390), and was stronger in older adults and adults with low education levels. There is a significant association between CIMT and cognitive function among middle-aged and older adults sampled from a Chinese population. This association was stronger in older adults and adults with low education levels.

Correlation Between Vision and Cognitive Function in the Elderly

PubMed Central

Spierer, Oriel; Fischer, Naomi; Barak, Adiel; Belkin, Michael

2016-01-01

Abstract The correlation between vision and cognition is not fully understood. Visual impairment in the elderly has been associated with impaired cognitive function, dementia, and Alzheimer disease. The aim was to study the correlation between near visual acuity (VA), refraction, and cognitive state in an elderly population. Subjects ≥75 years were enrolled in this cross-sectional study. Refraction and near VA was tested. Cognitive function was evaluated with a version of the mini-mental state examination for the visually impaired (MMSE-blind). The eye with better VA and no cataract or refractive surgery was analyzed. One-hundred ninety subjects (81.6 ± 5.1 years, 69.5% female) were included. Good VA (≤J3) was associated with high MMSE-blind (>17) (OR = 3.18, 95% CI = 1.57–6.43, P = 0.001). This remained significant adjusting for sex, age, and years of education. Wearing reading glasses correlated significantly with high MMSE-blind after adjustment for sex and age (OR = 2.14, 95% CI = 1.16–3.97, P = 0.016), but reached borderline significance after adjustment for education. There was a trend toward correlation between myopia and better MMSE-blind (r = −0.123, P = 0.09, Pearson correlation). Good VA and wearing glasses seem to correlate with better cognitive function. Reading glasses can serve as a protective factor against cognitive deterioration associated with sensory (visual) deprivation in old age. The association between myopia and cognition requires further investigation. PMID:26817872

Walking stabilizes cognitive functioning in Alzheimer's disease (AD) across one year

PubMed Central

Winchester, J.; Dick, M.B.; Gillen, D.; Reed, B.; Miller, B.; Tinklenberg, J.; Mungas, D.; Chui, H.; Galasko, D.; Hewett, L.; Cotman, C.W.

2013-01-01

AD is a public health epidemic, which seriously impacts cognition, mood and daily activities; however, one type of activity, exercise, has been shown to alter these states. Accordingly, we sought to investigate the relationship between exercise and mood, in early-stage AD patients (N = 104) from California, over a 1-year period. Patients completed the Mini-Mental State Examination (MMSE), Geriatric Depression Scale (GDS), and Blessed-Roth Dementia Rating Scale (BRDRS), while their caregivers completed the Yale Physical Activity Survey (YALE), Profile of Mood States (POMS), the Neuropsychiatric Inventory (NPI) and Functional Abilities Questionnaire (FAQ). Approximately half of the participants were female, from a variety of ethnic groups (Caucasian = 69.8%; Latino/Hispanic Americans = 20.1%). Our results demonstrated that the patients spent little time engaged in physical activity in general, their overall activity levels decreased over time, and this was paired with a change in global cognition (e.g., MMSE total score) and affect/mood (e.g., POMS score). Patients were parsed into Active and Sedentary groups based on their Yale profiles, with Active participants engaged in walking activities, weekly, over 1 year. Here, Sedentary patients had a significant decline in MMSE scores, while the Active patients had an attenuation in global cognitive decline. Importantly, among the Active AD patients, those individuals who engaged in walking for more than 2 h/week had a significant improvement in MMSE scores. Structured clinical trials which seek to increase the amount of time AD patients were engaged in walking activities and evaluate the nature and scope of beneficial effects in the brain are warranted. PMID:22959822

Validation of the Sinhala version of the Repeatable Battery for Assessment of Neuropsychological Status (RBANS)

PubMed

Suraweera, Chathurie; Anandakumar, D; Dahanayake, D; Subendran, M; Perera, U T; Hanwella, Raveen; de Silva, Varuni

2016-12-30

Only the Mini mental state examination (MMSE) and Montreal Cognitive Assessment scale have been validated in a Sri Lankan population for the assessment of cognitive functions. Both tests are deficient in the number of domains assessed. Therefore validation of Repeatable Battery for Assessment of Neuropsychological Status is important as it assesses most of the cognitive domains. To culturally adapt RBANS and investigate the validity and reliability of culturally adapted RBANS (RBANS-S). Fifty four participants with major neurocognitive disorder and 60 normal controls aged >50 were administered with RBANS-S at the Cognitive Assessment Unit, Faculty of Medicine, Colombo and National Hospital of Sri Lanka. The participants were selected after a detailed clinical assessment according to Diagnostic and Statistical Manual – 5 criteria. Data were analysed using SPSS data package. The mean age of the sample was 69.5 years. RBANS-S total scale correlated highly with MMSE total score, (Pearson correlational coefficient = 0.793 p=0.01). Criterion validity was assessed using receiver operating curve characteristic analysis and the area under the curve was 0.937. RBANS-S showed strong concurrent validity us indicated by its significant correlations with the MMSE. All of the RBANS-S subtests demonstrated significant correlations with the MMSE subsets. The sensitivity and specificity for RBANS-S was 89% and 85% respectively at a totals score of 80.5. The RBANS-S yielded a reliability coefficient of 0.929. Culturally adapted RBANS-S is a valid and reliable instrument which can be used in assessment of cognitive functions.

Development and validation of a new cognitive screening test: The Hong Kong Brief Cognitive Test (HKBC).

PubMed

Chiu, Helen F K; Zhong, Bao-Liang; Leung, Tony; Li, S W; Chow, Paulina; Tsoh, Joshua; Yan, Connie; Xiang, Yu-Tao; Wong, Mike

2018-07-01

To develop and examine the validity of a new brief cognitive test with less educational bias for screening cognitive impairment. A new cognitive test, Hong Kong Brief Cognitive Test (HKBC), was developed based on review of the literature, as well as the views of an expert panel. Three groups of subjects aged 65 or above were recruited after written consent: normal older people recruited in elderly centres, people with mild NCD (neurocognitive disorder), and people with major NCD. The brief cognitive test, Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment Scale (MoCA), were administered to the subjects. The performance of HKBC in differentiating subjects with major NCD, mild NCD, and normal older people were compared with the clinical diagnosis, as well as the MMSE and MoCA scores. In total, 359 subjects were recruited, with 99 normal controls, 132 subjects with major NCD, and 128 with mild NCD. The mean MMSE, MoCA, and HKBC scores showed significant differences among the 3 groups of subjects. In the receiving operating characteristic curve analysis of the HKBC in differentiating normal subjects from those with cognitive impairment (mild NCD + major NCD), the area under the curve was 0.955 with an optimal cut-off score of 21/22. The performances of MMSE and MoCA in differentiating normal from cognitively impaired subjects are slightly inferior to the HKBC. The HKBC is a brief instrument useful for screening cognitive impairment in older adults and is also useful in populations with low educational level. Copyright © 2018 John Wiley & Sons, Ltd.

Depressive status explains a significant amount of the variance in COPD assessment test (CAT) scores

PubMed Central

Miravitlles, Marc; Molina, Jesús; Quintano, José Antonio; Campuzano, Anna; Pérez, Joselín; Roncero, Carlos

2018-01-01

Background COPD assessment test (CAT) is a short, easy-to-complete health status tool that has been incorporated into the multidimensional assessment of COPD in order to guide therapy; therefore, it is important to understand the factors determining CAT scores. Methods This is a post hoc analysis of a cross-sectional, observational study conducted in respiratory medicine departments and primary care centers in Spain with the aim of identifying the factors determining CAT scores, focusing particularly on the cognitive status measured by the Mini-Mental State Examination (MMSE) and levels of depression measured by the short Beck Depression Inventory (BDI). Results A total of 684 COPD patients were analyzed; 84.1% were men, the mean age of patients was 68.7 years, and the mean forced expiratory volume in 1 second (%) was 55.1%. Mean CAT score was 21.8. CAT scores correlated with the MMSE score (Pearson’s coefficient r=−0.371) and the BDI (r=0.620), both p<0.001. In the multivariate analysis, the usual COPD severity variables (age, dyspnea, lung function, and comorbidity) together with MMSE and BDI scores were significantly associated with CAT scores and explained 45% of the variability. However, a model including only MMSE and BDI scores explained up to 40% and BDI alone explained 38% of the CAT variance. Conclusion CAT scores are associated with clinical variables of severity of COPD. However, cognitive status and, in particular, the level of depression explain a larger percentage of the variance in the CAT scores than the usual COPD clinical severity variables. PMID:29563782

Association between functional alterations of senescence and senility and disorders of gait and balance

PubMed Central

Teixeira-Leite, Homero; Manhães, Alex C.

2012-01-01

OBJECTIVES: Declines in cognition and mobility are frequently observed in the elderly, and it has been suggested that the appearance of gait disorders in older individuals may constitute a marker of cognitive decline that precedes significant findings in functional performance screening tests. This study sought to evaluate the relationship between functional capacities and gait and balance in an elderly community monitored by the Preventive and Integrated Care Unit of the Hospital Adventista Silvestre in Rio de Janeiro, RJ, Brazil. METHODS: Elderly individuals (193 females and 90 males) were submitted to a broad geriatric evaluation, which included the following tests: 1) a performance-oriented mobility assessment (POMA) to evaluate gait; 2) a mini-mental state examination (MMSE); 3) the use of Katz and Lawton scales to assess functional capacity; 4) the application of the geriatric depression scale (GDS); and 5) a mini-nutritional assessment (MNA) scale. RESULTS: Reductions in MMSE, Katz and Lawton scores were associated with reductions in POMA scores, and we also observed that significant reductions in POMA scores were present in persons for whom the MMSE and Katz scores did not clearly indicate cognitive dysfunction. We also demonstrated that a decline in the scores obtained with the GDS and MNA scales was associated with a decline in the POMA scores. CONCLUSIONS: Considering that significant alterations in the POMA scores were observed prior to the identification of significant alterations in cognitive capacity using either the MMSE or the Katz systems, a prospective study seems warranted to assess the predictive capacity of POMA scores regarding the associated decline in functional capacity. PMID:22892914

Association between functional alterations of senescence and senility and disorders of gait and balance.

PubMed

Teixeira-Leite, Homero; Manhães, Alex C

2012-07-01

Declines in cognition and mobility are frequently observed in the elderly, and it has been suggested that the appearance of gait disorders in older individuals may constitute a marker of cognitive decline that precedes significant findings in functional performance screening tests. This study sought to evaluate the relationship between functional capacities and gait and balance in an elderly community monitored by the Preventive and Integrated Care Unit of the Hospital Adventista Silvestre in Rio de Janeiro, RJ, Brazil. Elderly individuals (193 females and 90 males) were submitted to a broad geriatric evaluation, which included the following tests: 1) a performance-oriented mobility assessment (POMA) to evaluate gait; 2) a mini-mental state examination (MMSE); 3) the use of Katz and Lawton scales to assess functional capacity; 4) the application of the geriatric depression scale (GDS); and 5) a mini-nutritional assessment (MNA) scale. Reductions in MMSE, Katz and Lawton scores were associated with reductions in POMA scores, and we also observed that significant reductions in POMA scores were present in persons for whom the MMSE and Katz scores did not clearly indicate cognitive dysfunction. We also demonstrated that a decline in the scores obtained with the GDS and MNA scales was associated with a decline in the POMA scores. Considering that significant alterations in the POMA scores were observed prior to the identification of significant alterations in cognitive capacity using either the MMSE or the Katz systems, a prospective study seems warranted to assess the predictive capacity of POMA scores regarding the associated decline in functional capacity.

Efficacy of video-music therapy on quality of life improvement in a group of patients with Alzheimer's disease: a pre-post study.

PubMed

Rubbi, Ivan; Magnani, Daniela; Naldoni, Giada; Di Lorenzo, Rosaria; Cremonini, Valeria; Capucci, Patrizia; Artioli, Giovanna; Ferri, Paola

2016-11-22

Alzheimer's disease is the most common degenerative dementia with a predominantly senile onset. The difficult management of altered behaviour related to this disorder, poorly responsive to pharmacological treatments, has stimulated growth in non-pharmacological interventions, such as music therapy, whose effectiveness has not been supported by the literature up to now. The aim of this study was to evaluate the efficacy of video-music therapy on quality of life improvement in Patients affected by Alzheimer's Disease (AD). A pre-post study was conducted in a residential facility. 32 AD Patients, who attended this facility daily to participate in supportive and rehabilitative programs, were treated with 2 cycles of 6 video-music-therapy sessions, which consisted of folk music and video, recalling local traditions. In order to investigate their cognitive status, Mini Mental State Examination (MMSE) was administered and Patients were divided into stages according to MMSE scores. After each session of video-music-therapy, Quality of Life in Alzheimer's Disease Scale (QOL-AD) was administered to our Patients. 21 AD Patients completed the 2 cycles of video-music therapy. Among them, only the Patients with questionable, mild and moderate neurocognitive impairment (MMSE Stages 1, 2, 3) reported an improvement in their quality of life, whereas the Patients with severe deterioration (MMSE stage 4) did not report any change. Many items of QOL-AD improved, showing a statistically significantly correlation to each other. Video-music therapy was a valuable tool for improving the quality of life only in Patients affected by less severe neurocognitive impairment.

Is there information contained within the sentence-writing component of the mini mental state examination? A retrospective study of community dwelling older people.

PubMed

Shenkin, Susan D; Starr, John M; Dunn, Joanne M; Carter, Samantha; Deary, Ian J

2008-12-01

To investigate the relationship between features of the MMSE written sentence and cognitive function, depression and disability. MMSE sentences from 191 community dwelling individuals without dementia from the Lothian Birth Cohort 1921 (LBC1921) study were: (a) photocopied and (b) typed as written. Sentences were rated for objective criteria: word number and frequency, first person usage, time orientation, and letter case. Twenty healthy raters (50% male, age 20-26 years), blind to all other data, rated each handwritten and typed sentence for subjective criteria: legibility, 'emotional' tone (positive to negative), estimated age, health, and intelligence. As part of the LBC1921 volunteers had results available for cognitive ability tests (from which we extracted a general cognitive ability factor, g), Hospital Anxiety and Depression Score (HADS), and Townsend disability scores. 43.5% of subjects were male, mean age 78.6, SD 0.43 years. There was no significant association between the objective sentence criteria, legibility or tone and measured cognitive ability or physical disability. However, estimates of intelligence from the MMSE written sentence correlated significantly with current cognitive ability (r = 0.29, p < 0.001). There was a trend towards sentences with a negative tone being associated with a higher HADS-depression score (rho = -0.12, p = 0.09). In community dwelling people aged around 80 years, despite no association between objectively rated features of the MMSE sentence and intelligence or disability, raters were able to make better-than-chance estimates of subjects' intelligence test scores. (c) 2008 John Wiley & Sons, Ltd.

Mental status testing in the elderly nursing home population.

PubMed

Nadler, J D; Relkin, N R; Cohen, M S; Hodder, R A; Reingold, J; Plum, F

1995-07-01

The clinical utility of selected brief cognitive screening instruments in detecting dementia in an elderly nursing home population was examined. One hundred twenty nursing home residents (mean age 87.9) were administered the Mini-Mental State Exam (MMSE) and the Modified Mini-Mental State Exam (3MS). The majority of the subjects (75%) were also administered the Dementia Rating Scale (DRS). Both clinically diagnosed demented (n = 57) and non-demented (n = 63) subjects participated in the study. Dementia was diagnosed in accordance with DSM-III-R criteria by physicians specializing in geriatric medicine. Using standard cutoffs for impairment, the 3MS, MMSE, and DRS achieved high sensitivity (82% to 100%) but low specificity (33% to 52%) in the detection of dementia among nursing home residents. Positive predictive values ranged from 52% to 61%, and negative predictive values from 77% to 100%. Higher age, lower education, and history of depression were significantly associated with misclassification of non-demented elderly subjects. Receiver Operating Characteristic (ROC) curve analyses revealed optimal classification of dementia with cutoff values of 74 for the 3MS, 22 for the MMSE, and 110 for the DRS. The results suggest that the 3MS, MMSE, and DRS do not differ significantly with respect to classification accuracy of dementia in a nursing home population. Elderly individuals of advanced age (i.e., the oldest-old) with lower education and a history of depression appear at particular risk for dementia misclassification with these instruments. Revised cutoff values for impairment should be employed when these instruments are applied to elderly residents of nursing homes and the oldest-old.

Mild cognitive impairment in symptomatic and asymptomatic cerebrovascular disease.

PubMed

Popović, Irena Martinić; Serić, Vesna; Demarin, Vida

2007-06-15

We tried to evaluate and to compare usefulness of two brief cognitive tests in early detection of cognitive decline in subjects with increased cerebrovascular (CV) risk. As CV risk factors are recognised as important in etiology of dementia, we also aimed to determine the possible associations of specific CV risk factors and cognitive results. Patients (PGs) with first-ever stroke or TIA (N=110) and CV symptoms-free controls (CGs) with CV risk factors present (N=45) matched for age, gender and education level were tested using Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) on admission, at three- and six-month points. In all subjects, detailed CV risk factors profile was assessed. We observed the decrement in cognitive performance during the six-month study period in both groups, more evident if MoCA (p<0.001) than if MMSE was used (p=0.022). Six months after first stroke/TIA 83.6% PGs scored below normal range on MoCA. In PGs, positive associations for cognitive decrement and multiple CV risk factors (>2) were found (p=0.034 for MMSE; p=0.002 for MoCA). In CGs, positive associations were found for cognitive decrement and arterial hypertension with increased IMT values (p<0.001 for MMSE) and for multiple CV risk factors and arterial hypertension (p=0.003 for MoCA). The use of MoCA could aid to early recognition of cognitive deficits in persons with increased CV risk. Individuals with multiple CV risk factors seem to have increased risk of cognitive decline.

Effects of nutritional status and cognitive ability on olfactory function in geriatric patients.

PubMed

Jin, Sung-Yong; Jeong, Hye Seon; Lee, Jin Woo; Kwon, Ki Ryun; Rha, Ki-Sang; Kim, Yong Min

2016-02-01

The aim of this study was to investigate the prevalence of olfactory dysfunction and evaluate the relationship between olfactory function and nutritional status, comorbidity, and the results of a neurocognitive test in geriatric patients who do not suffer from neurodegenerative disease. A total of 45 patients who visited the Geriatric Health Center of Chungnam National University Hospital were enrolled in this study. Olfactory function was assessed using a Korean Version of Sniffin' Stick Test II. Cognitive status of all participants was assessed with the MMSE-K (Korean version of the Mini-Mental State Examination). Nutritional status was assessed with body mass index, Mini-Nutritional Assessment (MNA), and serum total protein and albumin. A total of 45 participants were enrolled in this study. Of these subjects, 28 were men and 17 were women, with a mean age of 71.7±5.16 years. Nine (20%) were normosmia, 13 (28.9%) were hyposmia, and 23 (51.1%) were anosmia. Thirty-six patients (80%) suffered from olfactory dysfunction (anosmia or hyposmia). MMSE score showed significant correlation with MNA score. There were significant negative correlations between age and total TDI (threshold, discrimination, and identification) score, discrimination score, identification score, and MMSE score. MMSE score showed significant correlation with discrimination score and identification score. However, MNA score did not show any significant correlation with olfactory function test results. Although olfactory function was not influenced by nutritional status, abilities of discrimination and identification of odors were associated with cognitive function in geriatric patients. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Depressive status explains a significant amount of the variance in COPD assessment test (CAT) scores.

PubMed

Miravitlles, Marc; Molina, Jesús; Quintano, José Antonio; Campuzano, Anna; Pérez, Joselín; Roncero, Carlos

2018-01-01

COPD assessment test (CAT) is a short, easy-to-complete health status tool that has been incorporated into the multidimensional assessment of COPD in order to guide therapy; therefore, it is important to understand the factors determining CAT scores. This is a post hoc analysis of a cross-sectional, observational study conducted in respiratory medicine departments and primary care centers in Spain with the aim of identifying the factors determining CAT scores, focusing particularly on the cognitive status measured by the Mini-Mental State Examination (MMSE) and levels of depression measured by the short Beck Depression Inventory (BDI). A total of 684 COPD patients were analyzed; 84.1% were men, the mean age of patients was 68.7 years, and the mean forced expiratory volume in 1 second (%) was 55.1%. Mean CAT score was 21.8. CAT scores correlated with the MMSE score (Pearson's coefficient r =-0.371) and the BDI ( r =0.620), both p <0.001. In the multivariate analysis, the usual COPD severity variables (age, dyspnea, lung function, and comorbidity) together with MMSE and BDI scores were significantly associated with CAT scores and explained 45% of the variability. However, a model including only MMSE and BDI scores explained up to 40% and BDI alone explained 38% of the CAT variance. CAT scores are associated with clinical variables of severity of COPD. However, cognitive status and, in particular, the level of depression explain a larger percentage of the variance in the CAT scores than the usual COPD clinical severity variables.

The Modified Telephone Interview for Cognitive Status is More Predictive of Memory Abilities Than the Mini-Mental State Examination.

PubMed

Duff, Kevin; Tometich, Danielle; Dennett, Kathryn

2015-09-01

Although not as popular as the Mini-Mental State Examination (MMSE), the modified Telephone Interview for Cognitive Status (mTICS) has some distinct advantages when screening cognitive functioning in older adults. The current study compared these 2 cognitive screening measures in their ability to predict performance on a memory composite (ie, delayed recall of verbal and visual information) in a cohort of 121 community-dwelling older adults, both at baseline and after 1 year. Both the MMSE and the mTICS significantly correlated with the memory composite at baseline (r's of .41 and .62, respectively) and at 1 year (r's of .36 and .50, respectively). At baseline, stepwise linear regression indicated that the mTICS and gender best predicted the memory composite score (R (2) = .45, P < .001), and the MMSE and other demographic variables did not significantly improve the prediction. At 1 year, the results were very similar. Despite its lesser popularity, the mTICS may be a more attractive option when screening for cognitive abilities in this age range. © The Author(s) 2015.

On the optimum signal constellation design for high-speed optical transport networks.

PubMed

Liu, Tao; Djordjevic, Ivan B

2012-08-27

In this paper, we first describe an optimum signal constellation design algorithm, which is optimum in MMSE-sense, called MMSE-OSCD, for channel capacity achieving source distribution. Secondly, we introduce a feedback channel capacity inspired optimum signal constellation design (FCC-OSCD) to further improve the performance of MMSE-OSCD, inspired by the fact that feedback channel capacity is higher than that of systems without feedback. The constellations obtained by FCC-OSCD are, however, OSNR dependent. The optimization is jointly performed together with regular quasi-cyclic low-density parity-check (LDPC) code design. Such obtained coded-modulation scheme, in combination with polarization-multiplexing, is suitable as both 400 Gb/s and multi-Tb/s optical transport enabling technology. Using large girth LDPC code, we demonstrate by Monte Carlo simulations that a 32-ary signal constellation, obtained by FCC-OSCD, outperforms previously proposed optimized 32-ary CIPQ signal constellation by 0.8 dB at BER of 10(-7). On the other hand, the LDPC-coded 16-ary FCC-OSCD outperforms 16-QAM by 1.15 dB at the same BER.

Cognitive cooperation groups mediated by computers and internet present significant improvement of cognitive status in older adults with memory complaints: a controlled prospective study.

PubMed

Krug, Rodrigo de Rosso; Silva, Anna Quialheiro Abreu da; Schneider, Ione Jayce Ceola; Ramos, Luiz Roberto; d'Orsi, Eleonora; Xavier, André Junqueira

2017-04-01

To estimate the effect of participating in cognitive cooperation groups, mediated by computers and the internet, on the Mini-Mental State Examination (MMSE) percent variation of outpatients with memory complaints attending two memory clinics. A prospective controlled intervention study carried out from 2006 to 2013 with 293 elders. The intervention group (n = 160) attended a cognitive cooperation group (20 sessions of 1.5 hours each). The control group (n = 133) received routine medical care. Outcome was the percent variation in the MMSE. Control variables included gender, age, marital status, schooling, hypertension, diabetes, dyslipidaemia, hypothyroidism, depression, vascular diseases, polymedication, use of benzodiazepines, exposure to tobacco, sedentary lifestyle, obesity and functional capacity. The final model was obtained by multivariate linear regression. The intervention group obtained an independent positive variation of 24.39% (CI 95% = 14.86/33.91) in the MMSE compared to the control group. The results suggested that cognitive cooperation groups, mediated by computers and the internet, are associated with cognitive status improvement of older adults in memory clinics.

Gender, Resources Across the Life Course, and Cognitive Functioning in Egypt

PubMed Central

YOUNT, KATHRYN M.

2008-01-01

In this article, I evaluate the life-course determinants of cognitive functioning among 1,003 women and men aged 50 and older in Ismailia, Egypt. Three questions motivate this analysis: (1) Do older women have poorer cognitive functioning than do older men?; (2) Do cognitive resources accrued in childhood and adulthood have net positive associations with later-life cognitive functioning for women and men?; and (3) To what extent do differences in the amounts and effects of women’s and men’s cognitive resources account for gaps in their cognitive functioning? Compared with men, women have lower Modified-Mini Mental Status Exam (M-MMSE) scores for overall cognitive functioning. Cognitive resources in childhood and adulthood are jointly associated with the M-MMSE score. About 83% of the gender gap in mean M-MMSE scores is attributable to gaps in men’s and women’s attributes across the life course. Gender gaps in childhood cognitive resources—and especially schooling attainment—account for the largest share (18%) of the residual gender gap in cognitive functioning. PMID:19110904

Cognitive impairment in patients with Fibromyalgia syndrome as assessed by the Mini-Mental State Examination

PubMed Central

2009-01-01

Background This study evaluated the frequency of cognitive impairment in patients with Fibromyalgia syndrome (FMS) using the Mini Mental State Examination (MMSE). Methods We analyzed baseline data from all 46 patients with FMS and 92 age- and sex-matched controls per diagnosis of neuropathic (NeP) or mixed pain (MP) selected from a larger prospective study. Results FMS had a slight but statistically significant lower score in the adjusted MMSE score (26.9; 95% CI 26.7-27.1) than either NeP (27.3; 95% CI 27.2-27.4) or MP (27.3; 27.2-27.5). The percentage of patients with congnitive impairment (adjusted MMSE ≤ 26) was numerically higher in FMS (15%; 95% CI 6.3-29) compared with NeP (5%; 95% CI 1.8-12.2) or MP (5%; 95% CI 1.8-12.2) and higher than in the same age stratum of the general population (0.05%). Conclusions Compared with the population reference value, patients with FMS showed high frequency of cognitive impairment. PMID:20025750

Cultural adaptation, standardization and clinical validity of the test your memory dementia screening instrument in Greek.

PubMed

Iatraki, Eliza; Simos, Panagiotis G; Lionis, Christos; Zaganas, Ioannis; Symvoulakis, Emmanouil K; Papastefanakis, Emmanouil; Panagiotakis, Simeon; Pantelidakis, Heraklis; Papadopoulos, Konstantinos; Tziraki, Chariklia

2014-01-01

To adapt and standardize the Test Your Memory (TYM) dementia screening instrument in Greek. Normative data on the Greek version of the TYM were obtained from a community sample of 239 adults aged 21-92 years. Clinical validity was assessed in a cohort of 134 Neurology Clinic patients. Concurrent validity was examined through comparisons with the Mini-Mental State Examination (MMSE) and the Greek Everyday Function Scale. Correlations between the TYM and the MMSE were 0.73 and 0.82 in the community and patient samples, respectively. Scores on both tests were moderately associated with everyday functional capacity. Using age- and education-corrected cutoff scores ranging from 26/50 to 45/50 points, the sensitivity of the TYM for Alzheimer's disease detection was found to be higher than that of the MMSE (0.82 vs. 0.70), although its specificity was lower (0.71 vs. 0.90). Findings are consistent with previous reports in a variety of cultural settings supporting the potential utility of the TYM as a dementia screening tool.

An observational clinical study of the efficacy and tolerability of donepezil in the treatment of Alzheimer's disease.

PubMed

Hager, Klaus; Calabrese, Pasquale; Frölich, Lutz; Göbel, Claus; Berger, Frank M

2003-01-01

An open-label, observational Post-Marketing Surveillance (PMS) study was undertaken in Germany to examine the efficacy and tolerability of donepezil in routine clinical practice. Alzheimer's disease (AD) patients were treated with donepezil (5 or 10 mg once daily) and observed for a period of approximately 3 months. Study assessments included the Mini-Mental State Examination (MMSE), the Nurses' Observation Scale for Geriatric Patients (NOSGER), and adverse events (AEs). A total of 2,092 patients (mean age 73.0 years; mean +/- SD MMSE score 17.8 +/- 5.8) were included in the efficacy assessments. MMSE and NOSGER scores showed statistically significant improvements in the total patient population and in the subpopulations with severe AD or AD with concomitant Parkinsonian symptoms (ADPS cohort). AEs were reported in a total of 12% of patients and were mostly due to peripheral cholinergic effects. In this observational PMS study, donepezil was shown to be an effective and well-tolerated therapy in the overall patient population, in patients with severe AD, and in the ADPS cohort. Copyright 2003 S. Karger AG, Basel

Memantine in the prevention or alleviation of electroconvulsive therapy induces cognitive disorders: A placebo controlled trial.

PubMed

Abbasinazari, Mohammad; Adib-Eshgh, Ladan; Rostami, Azin; Beyraghi, Narges; Dabir, Shideh; Jafari, Reyhaneh

2015-06-01

The purpose of this study was to evaluate the effect of memantine administration on the adverse cognitive effects of electroconvulsive therapy (ECT). Forty patients diagnosed with a major depressive disorder for which ECT was indicated as a treatment for their current episode were randomly allocated to either the memantine (5mg/day) group or the placebo group. All patients underwent the same protocol for anaesthesia and ECT procedures. The patients received memantine or the placebo for the whole period of ECT treatment, starting the day before ECT and continuing until the fourth session of ECT. The Modified Mental State Examination (MMSE) was used for the assessment of cognition before and after the trial. Regarding MMSE and item 3 MMSE (related to recent memory), the memantine group scored significantly higher at the end of ECT sessions than the control group (P=0.02, P<0.001, respectively). Our data support the hypothesis that memantine may reduce cognitive impairment following ECT. Memantine could be both a safe and well-tolerated treatment for use with ECT. Copyright © 2015 Elsevier B.V. All rights reserved.

Free-space optics mode-wavelength division multiplexing system using LG modes based on decision feedback equalization

NASA Astrophysics Data System (ADS)

Amphawan, Angela; Ghazi, Alaan; Al-dawoodi, Aras

2017-11-01

A free-space optics mode-wavelength division multiplexing (MWDM) system using Laguerre-Gaussian (LG) modes is designed using decision feedback equalization for controlling mode coupling and combating inter symbol interference so as to increase channel diversity. In this paper, a data rate of 24 Gbps is achieved for a FSO MWDM channel of 2.6 km in length using feedback equalization. Simulation results show significant improvement in eye diagrams and bit-error rates before and after decision feedback equalization.

Conditional Standard Errors, Reliability and Decision Consistency of Performance Levels Using Polytomous IRT.

ERIC Educational Resources Information Center

Wang, Tianyou; And Others

M. J. Kolen, B. A. Hanson, and R. L. Brennan (1992) presented a procedure for assessing the conditional standard error of measurement (CSEM) of scale scores using a strong true-score model. They also investigated the ways of using nonlinear transformation from number-correct raw score to scale score to equalize the conditional standard error along…

Local Observability Analysis of Star Sensor Installation Errors in a SINS/CNS Integration System for Near-Earth Flight Vehicles.

PubMed

Yang, Yanqiang; Zhang, Chunxi; Lu, Jiazhen

2017-01-16

Strapdown inertial navigation system/celestial navigation system (SINS/CNS) integrated navigation is a fully autonomous and high precision method, which has been widely used to improve the hitting accuracy and quick reaction capability of near-Earth flight vehicles. The installation errors between SINS and star sensors have been one of the main factors that restrict the actual accuracy of SINS/CNS. In this paper, an integration algorithm based on the star vector observations is derived considering the star sensor installation error. Then, the star sensor installation error is accurately estimated based on Kalman Filtering (KF). Meanwhile, a local observability analysis is performed on the rank of observability matrix obtained via linearization observation equation, and the observable conditions are presented and validated. The number of star vectors should be greater than or equal to 2, and the times of posture adjustment also should be greater than or equal to 2. Simulations indicate that the star sensor installation error could be readily observable based on the maneuvering condition; moreover, the attitude errors of SINS are less than 7 arc-seconds. This analysis method and conclusion are useful in the ballistic trajectory design of near-Earth flight vehicles.

Optimal design of multichannel equalizers for the structural similarity index.

PubMed

Chai, Li; Sheng, Yuxia

2014-12-01

The optimization of multichannel equalizers is studied for the structural similarity (SSIM) criteria. The closed-form formula is provided for the optimal equalizer when the mean of the source is zero. The formula shows that the equalizer with maximal SSIM index is equal to the one with minimal mean square error (MSE) multiplied by a positive real number, which is shown to be equal to the inverse of the achieved SSIM index. The relation of the maximal SSIM index to the minimal MSE is also established for given blurring filters and fixed length equalizers. An algorithm is also presented to compute the suboptimal equalizer for the general sources. Various numerical examples are given to demonstrate the effectiveness of the results.

[Effect of modified huanglian wendan decoction in treating senile patients with mild cognitive impairment of turbid-phlegm blocking orifice syndrome].

PubMed

Guo, Ren-zhen; Zhou, Wen-quan; Luo, Zeng-gang

2010-01-01

To observe the clinical efficacy of modified Huanglian Wendan Decoction (HWD) in treating senile mild cognitive impairment (MCI) of turbid-phlegm blocking orifice syndrome. With a block randomized, double-blinded and controlled design adopted, the 64 patients of MCI selected from December 2007 to February 2009 were randomly and equally assigned to two groups. The treatment group was treated with HWD in dose of 200 mL, twice a day; the control group was given Aniracetam 0.2 g (for patients over 70-years-old, 0.1 g) three times a day. And the illusive medicine in dosage-form of capsule/decoction simulated to that used in the opposite group was applied. The medication and observation lasted for three months. Chinese medicine syndrome, cognition capacity (by MMSE), laboratory indexes [acetylcholine (Ach), superoxide dismutase (SOD), malondialdehyde (MDA)] and safety related indexes in patients were observed. After treatment, MMSE score increased in both groups, but the increment in the treatment group was significantly higher than that in the control group (P<0.01); Chinese medicine syndrome estimated by scoring showed that after treatment, all scores of syndromes, excepting the expectoration, were improved in the treatment group with the post-treatment scores significantly lower than those in the control group respectively (P<0.05 or P<0.01); while in the control group, lowering of scores only showed in some symptoms such as poor memory, heavy head or dizziness, and heavy sensation in limbs and body. Serum levels of Ach and SOD decreased and MDA increased in both groups after treatment, but the change of Ach was more significant in the treatment group (P<0.01). No obvious adverse reactions were found during the treatment. For treatment of MCI, HWD shows effects in improving patients' symptoms, cognition capacity and elevating serum Ach content better than that of Aniracetam; and with effects for raising SOD activity and reducing MDA level similar to those of Aniracetam.

Development and effect of a cognitive enhancement gymnastics program for elderly people with dementia

PubMed Central

Han, Yoon-Soo; Araki, Tatsuo; Lee, Pil-Young; Choi, Jung-Hyun; Kwon, In-Seon; Kwon, Ki-Nam; Kim, Ji-Youn

2016-01-01

The purpose of this study was to develop a cognitive enhancement gymnastics program for the elderly with dementia and to verify its effect. The study was conducted on 27 people with dementia being treated in a dementia day care center in Incheon city. No statistically significant differences were found in the measures Mini-Mental State Examination for Dementia Screening (MMSE-DS), Short Geriatric Depression Scale (SGDS), Seoul Activities of Daily Living (S-ADL), or rock-paper-scissors. However, the MMSE-DS and rock-paper-scissors showed improvement after 12 weeks. PMID:27656632

The luminosity function of the CfA Redshift Survey

NASA Technical Reports Server (NTRS)

Marzke, R. O.; Huchra, J. P.; Geller, M. J.

1994-01-01

We use the CfA Reshift Survey of galaxies with m(sub z) less than or equal to 15.5 to calculate the galaxy luminosity function over the range -13 less than or equal to M(sub z) less than or equal to -22. The sample includes 9063 galaxies distributed over 2.1 sr. For galaxies with velocities cz greater or equal to 2500 km per sec, where the effects of peculiar velocities are small, the luminosity function is well represented by a Schechter function with parameters phi(sub star) = 0.04 +/- 0.01 per cu Mpc, M(sub star) = -18.8 +/- 0.3, and alpha = -1.0 +/- 0.2. When we include all galaxies with cz greater or equal to 500 km per sec, the number of galaxies in the range -16 less than or equal to M(sub z) less than or equal to -13 exceeds the extrapolation of the Schechter function by a factor of 3.1 +/- 0.5. This faint-end excess is not caused by the local peculiar velocity field but may be partially explained by small scale errors in the Zwicky magnitudes. Even with a scale error as large as 0.2 mag per mag, which is unlikely, the excess is still a factor of 1.8 +/- 0.3. If real, this excess affects the interpretation of deep counts of field galaxies.

Author Correction: Geometric constraints during epithelial jamming

NASA Astrophysics Data System (ADS)

Atia, Lior; Bi, Dapeng; Sharma, Yasha; Mitchel, Jennifer A.; Gweon, Bomi; Koehler, Stephan A.; DeCamp, Stephen J.; Lan, Bo; Kim, Jae Hun; Hirsch, Rebecca; Pegoraro, Adrian F.; Lee, Kyu Ha; Starr, Jacqueline R.; Weitz, David A.; Martin, Adam C.; Park, Jin-Ah; Butler, James P.; Fredberg, Jeffrey J.

2018-06-01

In the first correction to this Article, the authors added James P. Butler and Jeffrey J. Fredburg as equally contributing authors. However, this was in error; the statement should have remained indicating that Lior Atia, Dapeng Bi and Yasha Sharma contributed equally. This has now been corrected.

Computer simulations of interferometric imaging with the VLT Interferometer and the AMBER instrument

NASA Astrophysics Data System (ADS)

Bloecker, Thomas; Hofmann, Karl-Heinz; Przygodda, Frank; Weigelt, Gerd

2000-07-01

We present computer simulations of interferometric imaging with the VLT interferometer and the AMBER instrument. These simulations include both the astrophysical modeling of a stellar object by radiative transfer calculations and the simulation of light propagation from the object to the detector (through atmosphere, telescopes, and the AMBER instrument), simulation of photon noise and detector read- out noise, and finally data processing of the interferograms. The results show the dependence of the visibility error bars on the following observational parameters: different seeing during the observation of object and reference star (Fried parameters r0,object equals 2.4 m, r0,ref. equals 2.5 m), different residual tip- tilt error ((delta) tt,object equals 2% of the Airy disk diameter, (delta) tt,ref. equals 0.1%), and object brightness (Kobject equals 3.5 mag and 11 mag, Kref. equals 3.5 mag). Exemplarily, we focus on stars in late stages of stellar evolution and study one of its key objects, the dusty supergiant IRC + 10420 that is rapidly evolving on human timescales. We show computer simulations of VLTI interferometry of IRC + 10420 with two ATs (wide-field mode, i.e. without fiber optics spatial filters) and discuss whether the visibility accuracy is sufficient to distinguish between different theoretical model predictions.

Comparison of base flows to selected streamflow statistics representative of 1930-2002 in West Virginia

USGS Publications Warehouse

Wiley, Jeffrey B.

2012-01-01

Base flows were compared with published streamflow statistics to assess climate variability and to determine the published statistics that can be substituted for annual and seasonal base flows of unregulated streams in West Virginia. The comparison study was done by the U.S. Geological Survey, in cooperation with the West Virginia Department of Environmental Protection, Division of Water and Waste Management. The seasons were defined as winter (January 1-March 31), spring (April 1-June 30), summer (July 1-September 30), and fall (October 1-December 31). Differences in mean annual base flows for five record sub-periods (1930-42, 1943-62, 1963-69, 1970-79, and 1980-2002) range from -14.9 to 14.6 percent when compared to the values for the period 1930-2002. Differences between mean seasonal base flows and values for the period 1930-2002 are less variable for winter and spring, -11.2 to 11.0 percent, than for summer and fall, -47.0 to 43.6 percent. Mean summer base flows (July-September) and mean monthly base flows for July, August, September, and October are approximately equal, within 7.4 percentage points of mean annual base flow. The mean of each of annual, spring, summer, fall, and winter base flows are approximately equal to the annual 50-percent (standard error of 10.3 percent), 45-percent (error of 14.6 percent), 75-percent (error of 11.8 percent), 55-percent (error of 11.2 percent), and 35-percent duration flows (error of 11.1 percent), respectively. The mean seasonal base flows for spring, summer, fall, and winter are approximately equal to the spring 50- to 55-percent (standard error of 6.8 percent), summer 45- to 50-percent (error of 6.7 percent), fall 45-percent (error of 15.2 percent), and winter 60-percent duration flows (error of 8.5 percent), respectively. Annual and seasonal base flows representative of the period 1930-2002 at unregulated streamflow-gaging stations and ungaged locations in West Virginia can be estimated using previously published values of statistics and procedures.

Predicted blood glucose from insulin administration based on values from miscoded glucose meters.

PubMed

Raine, Charles H; Pardo, Scott; Parkes, Joan Lee

2008-07-01

The proper use of many types of self-monitored blood glucose (SMBG) meters requires calibration to match strip code. Studies have demonstrated the occurrence and impact on insulin dose of coding errors with SMBG meters. This paper reflects additional analyses performed with data from Raine et al. (JDST, 2:205-210, 2007). It attempts to relate potential insulin dose errors to possible adverse blood glucose outcomes when glucose meters are miscoded. Five sets of glucose meters were used. Two sets of meters were autocoded and therefore could not be miscoded, and three sets required manual coding. Two of each set of manually coded meters were deliberately miscoded, and one from each set was properly coded. Subjects (n = 116) had finger stick blood glucose obtained at fasting, as well as at 1 and 2 hours after a fixed meal (Boost((R)); Novartis Medical Nutrition U.S., Basel, Switzerland). Deviations of meter blood glucose results from the reference method (YSI) were used to predict insulin dose errors and resultant blood glucose outcomes based on these deviations. Using insulin sensitivity data, it was determined that, given an actual blood glucose of 150-400 mg/dl, an error greater than +40 mg/dl would be required to calculate an insulin dose sufficient to produce a blood glucose of less than 70 mg/dl. Conversely, an error less than or equal to -70 mg/dl would be required to derive an insulin dose insufficient to correct an elevated blood glucose to less than 180 mg/dl. For miscoded meters, the estimated probability to produce a blood glucose reduction to less than or equal to 70 mg/dl was 10.40%. The corresponding probabilities for autocoded and correctly coded manual meters were 2.52% (p < 0.0001) and 1.46% (p < 0.0001), respectively. Furthermore, the errors from miscoded meters were large enough to produce a calculated blood glucose outcome less than or equal to 50 mg/dl in 42 of 833 instances. Autocoded meters produced zero (0) outcomes less than or equal to 50 mg/dl out of 279 instances, and correctly coded manual meters produced 1 of 416. Improperly coded blood glucose meters present the potential for insulin dose errors and resultant clinically significant hypoglycemia or hyperglycemia. Patients should be instructed and periodically reinstructed in the proper use of blood glucose meters, particularly for meters that require coding.

Mini-Mental State Examination (MMSE) for the detection of dementia in clinically unevaluated people aged 65 and over in community and primary care populations.

PubMed

Creavin, Sam T; Wisniewski, Susanna; Noel-Storr, Anna H; Trevelyan, Clare M; Hampton, Thomas; Rayment, Dane; Thom, Victoria M; Nash, Kirsty J E; Elhamoui, Hosam; Milligan, Rowena; Patel, Anish S; Tsivos, Demitra V; Wing, Tracey; Phillips, Emma; Kellman, Sophie M; Shackleton, Hannah L; Singleton, Georgina F; Neale, Bethany E; Watton, Martha E; Cullum, Sarah

2016-01-13

The Mini Mental State Examination (MMSE) is a cognitive test that is commonly used as part of the evaluation for possible dementia. To determine the diagnostic accuracy of the Mini-Mental State Examination (MMSE) at various cut points for dementia in people aged 65 years and over in community and primary care settings who had not undergone prior testing for dementia. We searched the specialised register of the Cochrane Dementia and Cognitive Improvement Group, MEDLINE (OvidSP), EMBASE (OvidSP), PsycINFO (OvidSP), LILACS (BIREME), ALOIS, BIOSIS previews (Thomson Reuters Web of Science), and Web of Science Core Collection, including the Science Citation Index and the Conference Proceedings Citation Index (Thomson Reuters Web of Science). We also searched specialised sources of diagnostic test accuracy studies and reviews: MEDION (Universities of Maastricht and Leuven, www.mediondatabase.nl), DARE (Database of Abstracts of Reviews of Effects, via the Cochrane Library), HTA Database (Health Technology Assessment Database, via the Cochrane Library), and ARIF (University of Birmingham, UK, www.arif.bham.ac.uk). We attempted to locate possibly relevant but unpublished data by contacting researchers in this field. We first performed the searches in November 2012 and then fully updated them in May 2014. We did not apply any language or date restrictions to the electronic searches, and we did not use any methodological filters as a method to restrict the search overall. We included studies that compared the 11-item (maximum score 30) MMSE test (at any cut point) in people who had not undergone prior testing versus a commonly accepted clinical reference standard for all-cause dementia and subtypes (Alzheimer disease dementia, Lewy body dementia, vascular dementia, frontotemporal dementia). Clinical diagnosis included all-cause (unspecified) dementia, as defined by any version of the Diagnostic and Statistical Manual of Mental Disorders (DSM); International Classification of Diseases (ICD) and the Clinical Dementia Rating. At least three authors screened all citations.Two authors handled data extraction and quality assessment. We performed meta-analysis using the hierarchical summary receiver-operator curves (HSROC) method and the bivariate method. We retrieved 24,310 citations after removal of duplicates. We reviewed the full text of 317 full-text articles and finally included 70 records, referring to 48 studies, in our synthesis. We were able to perform meta-analysis on 28 studies in the community setting (44 articles) and on 6 studies in primary care (8 articles), but we could not extract usable 2 x 2 data for the remaining 14 community studies, which we did not include in the meta-analysis. All of the studies in the community were in asymptomatic people, whereas two of the six studies in primary care were conducted in people who had symptoms of possible dementia. We judged two studies to be at high risk of bias in the patient selection domain, three studies to be at high risk of bias in the index test domain and nine studies to be at high risk of bias regarding flow and timing. We assessed most studies as being applicable to the review question though we had concerns about selection of participants in six studies and target condition in one study.The accuracy of the MMSE for diagnosing dementia was reported at 18 cut points in the community (MMSE score 10, 14-30 inclusive) and 10 cut points in primary care (MMSE score 17-26 inclusive). The total number of participants in studies included in the meta-analyses ranged from 37 to 2727, median 314 (interquartile range (IQR) 160 to 647). In the community, the pooled accuracy at a cut point of 24 (15 studies) was sensitivity 0.85 (95% confidence interval (CI) 0.74 to 0.92), specificity 0.90 (95% CI 0.82 to 0.95); at a cut point of 25 (10 studies), sensitivity 0.87 (95% CI 0.78 to 0.93), specificity 0.82 (95% CI 0.65 to 0.92); and in seven studies that adjusted accuracy estimates for level of education, sensitivity 0.97 (95% CI 0.83 to 1.00), specificity 0.70 (95% CI 0.50 to 0.85). There was insufficient data to evaluate the accuracy of the MMSE for diagnosing dementia subtypes.We could not estimate summary diagnostic accuracy in primary care due to insufficient data. The MMSE contributes to a diagnosis of dementia in low prevalence settings, but should not be used in isolation to confirm or exclude disease. We recommend that future work evaluates the diagnostic accuracy of tests in the context of the diagnostic pathway experienced by the patient and that investigators report how undergoing the MMSE changes patient-relevant outcomes.

[Correlates of change in cognitive function during a two-year follow-up period in a comprehensive health examination for the community-dwelling elderly for the prevention of geriatric syndromes and bed-ridden state].

PubMed

Iwasa, Hajime; Suzuki, Takao; Yoshida, Yuko; Kwon, Jinhee; Yoshida, Hideyo; Kim, Hunkyung; Sugiura, Miho; Furuna, Taketo

2006-11-01

We explored correlates of change in cognitive function during a two-year follow-up period among the community-dwelling elderly in Japan, using a population-based prospective approach. The participants analyzed in the present study were 260 men and 222 women aged 70 to 84 years at baseline, living in an urban Japanese community. Data such as change in cognitive function during two years (calculated by subtracting baseline Mini-Mental State Examination [MMSE] score from follow-up MMSE score: a negative value means a decrease in MMSE scores during the two-year period) as an outcome variable, age, education, hearing and vision problems, IADL deficit (measured by the Tokyo Metropolitan Institute of Gerontology of Index of Competence), problems related to memory complaint, living alone, hemoglobin level, as explanatory variables, and the baseline MMSE score, depressive status (measured by the Mini-International Neuropsychiatric Interview), chronic conditions (hypertension, stroke, and diabetes mellitus) as covariates, were collected during a comprehensive health examination survey for the elderly. We conducted multivariate regression analysis by genders to explore correlates of change in cognitive function. The results showed that higher age (beta = -0.18), presence of hearing problem (beta = -0.21), presence of IADL deficit (beta = -0.15), and memory complaint (beta = -0.20) in men, and higher age (beta = -0.27), low education level (beta = -0.25) and lower hemoglobin level (beta = 0.16) in women, were significantly associated with change in cognitive function when adjusting for the potential confounders. These factors may be reliable predictors for cognitive decline.

Distinct Patterns of Cognitive Aging Modified by Education Level and Gender among Adults with Limited or No Formal Education: A Normative Study of the Mini-Mental State Examination.

PubMed

Xie, Haiqun; Zhang, Chengguo; Wang, Yukai; Huang, Shuyun; Cui, Wei; Yang, Wenbin; Koski, Lisa; Xu, Xiping; Li, Youbao; Zheng, Meili; He, Mingli; Fu, Jia; Shi, Xiuli; Wang, Kai; Tang, Genfu; Wang, Binyan; Huo, Yong

2016-01-01

Dementia is increasingly prevalent due to rapid aging of the population, but under-recognized among people with low education levels. This is partly due to a lack of appropriate and precise normative data, which underestimates cognitive aging in the use of screening tools for dementia. We aimed to improve the precision of screening for cognitive impairment, by characterizing the patterns of cognitive aging and derived normative data of the Mini-Mental State Examination (MMSE) for illiterate and low-educated populations. This community-based study included data from 2,280 individuals aged 40 years or older from two rural areas. Multiple linear modeling examined the effect of aging on cognition reflected by the MMSE, stratified by education level and gender. Threshold effect of age on cognition was performed using a smoothing function. The majority of participants (60.4%) were illiterate or had attended only primary school (24.6%). The effect of aging on cognition varied by gender and education. Primary-school educated females and males remained cognitively stable up to 62 and 71 years of age, respectively, with MMSE score declining 0.4 and 0.8 points/year in females and males thereafter. Illiterates females scored 2.3 points lower than illiterate males, and scores for both declined 0.2 points/year. According to these results, normative data stratified by age, education and gender was generated. This study suggests gender and educational differences exist in cognitive aging among adults with limited or no formal education. To improve screening precision for cognitive impairment with the use of MMSE in low-educated population, age, gender, and education level should be considered.

Benefits of use, and tolerance of, medium-chain triglyceride medical food in the management of Japanese patients with Alzheimer's disease: a prospective, open-label pilot study.

PubMed

Ohnuma, Tohru; Toda, Aiko; Kimoto, Ayako; Takebayashi, Yuto; Higashiyama, Ryoko; Tagata, Yuko; Ito, Masanobu; Ota, Tsuneyoshi; Shibata, Nobuto; Arai, Heii

2016-01-01

This is the first clinical trial of this type in Japan, designed to analyze two important aspects of Alzheimer's disease (AD) management using medium-chain triglycerides. Axona was administered for 3 months (40 g of powder containing 20 g of caprylic triglycerides). We used an indurating, four-step dose-titration method (from 10 to 40 g per day) for 7 days before the trial, and examined the tolerance and adverse effects of this intervention. We also investigated its effect on cognitive function in mild-to-moderate AD patients. This was a clinical intervention in 22 Japanese patients with sporadic AD at a mild-to-moderate stage (ten females, 12 males), mean age (± standard deviation) 63.9 (±8.5) years, Mini-Mental State Examination (MMSE) score, 10-25, seven patients were ApoE4-positive. During Axona administration, we examined changes in cognitive function by obtaining MMSE and AD assessment-scale scores. Intolerance and serum ketone concentrations were also examined. The tolerance of Axona was good, without severe gastrointestinal adverse effects. Axona did not improve cognitive function in our sample of AD patients, even in those patients without the ApoE4 allele. However, some ApoE4-negative patients with baseline MMSE score ≥14 showed improvement in their cognitive functions. The modified dose-titration method, starting with a low dose of Axona, decreased gastrointestinal adverse effects in Japanese patients. Axona might be effective for some relatively mildly affected patients with AD (with cognitive function MMSE score of ≥14 and lacking the ApoE4 allele).

Development of a tool for assessment and care planning for dementia-related problem behaviors in home and community-based services programs: the Problem Behavior Inventory.

PubMed

Phillips, V L; Diwan, Sadhna; Egner, Amanda

2002-01-01

To describe development, validity, and application of the Problem Behavior Inventory (PBI), a tool to assess dementia-related problem behaviors (DRPBs) in community-based populations. Demographic, contact, and disease-specific data were extracted from client files from a Medicaid-funded home and community-based services program. Primary caregivers completed standard surveys relating to the care recipients' memory, mood, and behaviors. The client (care recipient) completed the Mini-Mental Status Exam (MMSE). Cognitively impaired clients, enrolled in the Community Care Services Program (CCSP) during a reference month, and their primary caregivers, were identified by CCSP case managers for participation in the study. Primary caregivers completed the Revised Memory and Behavior Problem Checklist (RMBPC). Clients screening positive for the presence of DRPBs based on caregiver responses to the RMBPC were then assessed using the Problem Behavior Inventory (PBI). Within the CCSP sample, the most prevalent behavior was appearing sad or depressed (67%), while the most frequent behavior was seeking attention, occurring at least daily in 58% of the group. The most bothersome behaviors were being sexually inappropriate, wandering, and misbehaving in public. Examination by behavior category (physical, verbal, mood, etc.) revealed a strong relationship between level of bother and behavior frequency. Frequency of verbal behaviors was positively related to MMSE scores, whereas frequency of ADL-related behaviors was inversely related to MMSE scores. Bother scores were not associated with MMSE scores. This study documents that the PBI is a valid, useful, and feasible tool for assessing DRPBs in community populations. Case managers using the PBI can determine specific problem behavior areas among client populations and for individual clients and institute client-specific interventions to address each issue.

Migraine is associated with better cognition in the middle-aged and elderly: the Rotterdam Study.

PubMed

Wen, K; Nguyen, N T; Hofman, A; Ikram, M A; Franco, O H

2016-10-01

Converging evidence suggests that migraine has, in part, a vascular basis. In turn, vascular pathology is a strong risk factor for cognitive decline. In this population-based study, we studied cognition amongst individuals with and without migraine. In 6708 participants of the Rotterdam Study, migraine was assessed using a validated questionnaire. Cognition was assessed by the Mini Mental State Examination (MMSE) and a dedicated cognitive test battery. Participants were classified as non-migraineurs (n = 5399), migraineurs (n = 1021) or probable migraineurs (n = 288). Multivariable linear regression was used to cross-sectionally evaluate the association between migraine and cognition, adjusting for age, sex and cardiovascular risk factors. Additionally, we stratified the analysis by sex and by migraine subtype. Migraineurs had higher mean MMSE scores [unstandardized regression coefficient 0.21, (95% confidence interval, 0.08; 0.34)] and global cognition [0.10 (0.04; 0.15)] than non-migraineurs. This difference was particularly marked for migraineurs with aura [MMSE: 0.39 (0.13; 0.66); global cognition: 0.13 (0.01; 0.24)]. Migraineurs performed better on tests of executive function and fine motor skills amongst specific cognitive domains. The difference in MMSE between migraineurs and non-migraineurs was greater in women [0.25 (0.10; 0.40)] than in men [0.13 (-0.15; 0.40)], whereas the difference in global cognition was similar in men and women [0.15 (0.04; 0.27) and 0.09 (0.02; 0.15), respectively]. Migraineurs, particularly migraineurs with aura, tend to score higher in cognition tests than non-migraineurs. More studies are needed to corroborate these findings. © 2016 EAN.

The association between orthostatic hypotension and cognitive state among adults 65 years and older who underwent a comprehensive geriatric assessment

PubMed Central

Punchick, Boris; Freud, Tamar; Press, Yan

2016-01-01

Abstract The prevalence of cognitive impairment and orthostatic hypotension (OH) increases with age, but the results of studies that assessed possible associations between them are inconsistent. The aim of this study is to assess possible associations between cognitive impairment and OH in patients ≥65 years of age who underwent a comprehensive geriatric assessment. A retrospective analysis was conducted of the computerized medical records of the study population from 2005 to 2013. Data collected included blood pressure measurements that enabled the calculation of OH, results of the mini-mental state examination (MMSE), results of the Montreal cognitive assessment (MoCA) test, and cognitive diagnoses that were determined over the course of the assessment. The rate of OH in the study population of 571 adults was 32.1%. The mean MMSE score was 22.5 ± 5.2 among participants with OH and 21.6 ± 5.8 among those without OH (P = 0.09). The absence of a significant association between OH and MMSE remained after adjusting the MMSE score for age and education level. The mean MoCA score was 16.4 ± 5.0 among participants with OH and 16.4 ± 4.8 among those without (P = 0.33). The prevalence of OH was 39% among participants without cognitive impairment, 28.9% among those with mild cognitive impairment (MCI), and 30.6% among those with dementia (P = 0.13). There was no association between OH and cognitive impairment in adults who underwent a comprehensive geriatric assessment. PMID:27442658

Racial and sex differences in associations between activities of daily living and cognition in community-dwelling older adults.

PubMed

Garrett, Stephanie L; Sawyer, Patricia; Kennedy, Richard E; McGuire, Dawn; Simon, Roger P; Strothers, Harry S; Allman, Richard M

2013-12-01

To examine the association between function measured according to activities of daily living (ADLs), instrumental activ1ities of daily living (IADLs), and cognition assessed according to Mini-Mental State Examination (MMSE) scores of older African-American and non-Hispanic white community-dwelling men and women. Cross-sectional study assessing associations between self-reported ADL and IADL difficulty and MMSE scores for race- and sex-specific groups. Homes of community-dwelling older adults. A random sample of 974 African-American and non-Hispanic white Medicare beneficiaries aged 65 and older living in west-central Alabama and participating in the University of Alabama at Birmingham Study of Aging, excluding those with reported diagnoses of dementia or with missing data. Function, based on self-reported difficulty in performing ADLs and IADLs, and cognition, using the MMSE. Multivariable linear regression models were used to test the association between function and cognition in race- and sex-specific groups after adjusting for covariates. Mini-Mental State Examination scores were modestly correlated with ADL and IADL difficulty in all four race- and sex-specific groups, with Pearson correlation coefficients ranging from −0.189 for non-Hispanic white women to −0.429 for African-American men. Correlations between MMSE and ADL or IADL difficulty in any of the race- and sex-specific groups were no longer significant after controlling for sociodemographic factors and comorbidities. Mini-Mental State Examination was not significantly associated with functional difficulty in older African-American and non-Hispanic white men and women after adjusting for sociodemographic factors and comorbidities, suggesting a mediating role in the relationship between cognition and function. © 2013, Copyright the Authors Journal compilation © 2013, The American Geriatrics Society.

Scenery Picture Memory Test: A new type of quick and effective screening test to detect early stage Alzheimer’s disease patients

PubMed Central

Takechi, Hajime; Dodge, Hiroko H

2010-01-01

Aim It is highly desirable to develop a neuropsychological screening test which is sensitive to the early stage of Alzheimer’s disease (AD), and is easy to administer at the primary care physician’s (PCP’s) office. Methods Participants were 128 AD patients and 54 healthy volunteers. Brief cognitive screening tests were administered to the participants including the Mini-Mental State Examination (MMSE), Clock Drawing Test (CDT), Verbal Fluency Test (VFT), a Verbal Category Cued Memory test (CCMT) and the Scenery Picture Memory Test (SPMT). In the SPMT, a scenery picture of a living room containing 23 familiar objects was used. The administration of the SPMT comprised the first shallow memory session (Pict 1) and the second deep memory session (Pict 2). The area under the receiver–operator curve (AUC) was used to compare the efficacy of SPMT with other cognitive tests. Results Pict 1, which requires less than 2 min to complete, had the same AUC as Pict 2, and showed significantly larger AUC than MMSE, CDT and VFT for all (MMSE 19–23) and very mild (MMSE ≥ 24) AD patients. When we conducted the similar analysis separately for those younger than 75 years and those aged 75 years or older, we obtained the same results as above among the older age group. Pict 1 showed larger AUC than CCMT in overall sample and also in the older age group, although the difference was not statistically significant. Conclusion The SPMT could be useful for detection of mild and very mild AD in settings even where time is limited. PMID:20446933

Aging-Related Oxidative Stress: Positive Effect of Memory Training.

PubMed

Pesce, Mirko; Tatangelo, Raffaella; La Fratta, Irene; Rizzuto, Alessia; Campagna, Giovanna; Turli, Cinzia; Ferrone, Alessio; Franceschelli, Sara; Speranza, Lorenza; Patruno, Antonia; Ballerini, Patrizia; De Lutiis, Maria Anna; Felaco, Mario; Grilli, Alfredo

2018-02-01

The cognitive impairment characterizing the phenotype of older adults has been related to the efficiency of the antioxidant system. This study aimed at investigating the effect of memory training (MT) on memory, global cognitive functioning, and the oxidant and antioxidant capacity of plasma. We recruited 52 healthy subjects aged over 60. Twenty-nine subjects were submitted to 6-months of MT (Experimental Group, EG), and 23 were used as a Control Group (CG). Global cognitive functioning was assessed by the Mini-Mental State Examination (MMSE) and Short- and Long-Term Memory (STM and LTM, respectively) by the Rey Auditory Verbal Learning Test (RAVLT) at baseline (T0) and after 6-months (T1). Meanwhile, Reactive Oxygen Metabolites derivative compounds (d-ROMs), Biological Antioxidant Potential (BAP), and their ratio were evaluated on plasma. Results showed that the MMSE and RAVLT scores improved in EG at T1. At the same time, the d-ROMs levels significantly decreased, while the BAP and BAP/d-ROMs ratio showed an opposite trend. In both groups, the MMSE and LTM scores were negatively associated with d-ROMs levels, and positively correlated with BAP levels and the BAP/d-ROMs ratio. When we considered the Δvalue (Δvariable = variable post-MT minus variable pre-MT) in EG, the ΔMMSE and ΔLTM scores were negatively associated to Δd-ROMs, and positively to ΔBAP and ΔBAP/dROM. In conclusion, our results suggest that MT improves memory and global cognitive functioning. These processes were significantly associated to increase in resistance against oxidative stress at the plasma level in healthy older adults. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Association between oxidized low-density lipoprotein and cognitive impairment in patients with ischemic stroke.

PubMed

Wang, A; Liu, J; Meng, X; Li, J; Wang, H; Wang, Y; Su, Z; Zhang, N; Dai, L; Wang, Y; Wang, Y

2018-01-01

The association between oxidized low-density lipoprotein (oxLDL) and cognitive impairment is unclear. This study aimed to investigate the potential association between oxLDL and cognitive impairment among patients with acute ischemic stroke. We measured the levels of oxLDL and recorded the Mini-Mental State Examination (MMSE) score in patients with acute ischemic stroke who were recruited from the Study of Oxidative Stress in Patients with Acute Ischemic Stroke. Cognitive impairment was defined as an MMSE score of <24. The association between oxLDL and cognitive impairment was assessed by multivariate logistic or linear regression analysis. Other clinical variables of interest were also studied. A total of 3726 patients [1287 (34.54%) female] were included in this study, with a mean age of 63.62 ± 11.96 years. After adjusting for potential confounders in our logistic regression model, each SD increase in oxLDL was associated with a 26% increase in the prevalence of cognitive impairment (odds radio, 1.26; 95% confidence interval, 1.13-1.39; P < 0.0001). Similarly, higher oxLDL was associated with lower MMSE scores, with a 0.56-point decrease in MMSE score for every SD increase in oxLDL in a linear regression analysis (β = -0.56; 95% confidence interval, -0.81 to -0.32; P < 0.0001). There were no significant interactions between oxLDL and age, sex or education levels for cognitive impairment (all interactions, P > 0.05). Elevated levels of oxLDL were associated with a higher prevalence of cognitive impairment in patients with ischemic stroke. © 2017 EAN.

Regression-Based Estimates of Observed Functional Status in Centenarians

PubMed Central

Mitchell, Meghan B.; Miller, L. Stephen; Woodard, John L.; Davey, Adam; Martin, Peter; Burgess, Molly; Poon, Leonard W.

2011-01-01

Purpose of the Study: There is lack of consensus on the best method of functional assessment, and there is a paucity of studies on daily functioning in centenarians. We sought to compare associations between performance-based, self-report, and proxy report of functional status in centenarians. We expected the strongest relationships between proxy reports and observed performance of basic activities of daily living (BADLs) and instrumental activities of daily living (IADLs). We hypothesized that the discrepancy between self-report and observed daily functioning would be modified by cognitive status. We additionally sought to provide clinicians with estimates of centenarians’ observed daily functioning based on their mental status in combination with subjective measures of activities of daily living (ADLs). Design and Methods: Two hundred and forty-four centenarians from the Georgia Centenarian Study were included in this cross-sectional population-based study. Measures included the Direct Assessment of Functional Status, self-report and proxy report of functional status, and the Mini-Mental State Examination (MMSE). Results: Associations between observed and proxy reports were stronger than between observed and self-report across BADL and IADL measures. A significant MMSE by type of report interaction was found, indicating that lower MMSE performance is associated with a greater discrepancy between subjective and objective ADL measures. Implications: Results demonstrate associations between 3 methods of assessing functional status and suggest proxy reports are generally more accurate than self-report measures. Cognitive status accounted for some of the discrepancy between observed and self-reports, and we provide clinicians with tables to estimate centenarians’ performance on observed functional measures based on MMSE and subjective report of functional status. PMID:20974657

Cognitive function and walking velocity in people with dementia; a comparison of backward and forward walking.

PubMed

Johansson, Hanna; Lundin-Olsson, Lillemor; Littbrand, Håkan; Gustafson, Yngve; Rosendahl, Erik; Toots, Annika

2017-10-01

How forward and backward walking, both central to everyday life, relate to cognition are relatively unexplored in people with dementia. This study aimed to investigate if forward and backward walking velocity respectively, associated with global cognition and executive function in people with dementia, and whether the association differed according to walking aid use or dementia type. Using a cross-sectional design, 161 participants (77% women), a mean Mini-Mental State Examination (MMSE) score of 15, and mean age of 85.5years and living in nursing homes were included. Self-paced forward walking (FW) and backward walking (BW) velocity over 2.4m was measured. Global cognitive outcome measurements included MMSE and Alzheimer Disease Assessment Scale - Cognitive subscale (ADAS-Cog). Executive function was measured using Verbal Fluency (VF). In comprehensively adjusted multivariate linear regression analyses, FW was independently associated with VF (p=0.001), but not MMSE (p=0.126) or ADAS-Cog (p=0.818). BW was independently associated with VF (p=0.043) and MMSE (p=0.022), but not ADAS-Cog (p=0.519). Interaction analyses showed that the association between BW velocity and executive function were stronger in participants who walked without a walking aid. No associations differed according to dementia type. In conclusion, executive function appears important to walking velocity, both forward and backward, in people with dementia with mild to moderately severe cognitive impairment. Global cognitive function was associated with backward walking only, perhaps due to it being more challenging. The association between BW velocity and executive function differed according to use of walking aids, which appeared to attenuate the association. Copyright © 2017 Elsevier B.V. All rights reserved.

Low intakes of carotene, vitamin B2 , pantothenate and calcium predict cognitive decline among elderly patients with diabetes mellitus: The Japanese Elderly Diabetes Intervention Trial.

PubMed

Araki, Atsushi; Yoshimura, Yukio; Sakurai, Takashi; Umegaki, Hiroyuki; Kamada, Chiemi; Iimuro, Satoshi; Ohashi, Yasuo; Ito, Hideki

2017-08-01

The present study aimed to examine whether nutrient intakes predicted cognitive decline among elderly patients with diabetes mellitus. This study evaluated data from a 6-year prospective follow up of 237 elderly patients (aged ≥65 years) with diabetes mellitus, and the associations of baseline nutrient intakes with cognitive decline. Cognitive decline was defined as a ≥2-point decrease in the Mini-Mental State Examination (MMSE) score. Intakes of food and nutrients were assessed using a validated food frequency questionnaire, and were compared between patients with cognitive decline and intact cognition. Analysis of covariance and logistic regression analysis were used to compare the changes in the MMSE score during the follow up among intake tertile groups for each nutrient. Compared with men with intact cognition, the men with cognitive decline had lower baseline intakes of calcium, vitamin A, vitamin B 2 , pantothenate, soluble fiber, green vegetables and milk. However, no significant associations between cognitive decline and nutrient intakes were observed among women. After adjusting for age, body mass index, glycated hemoglobin levels, history of severe hypoglycemia, previous stroke and baseline MMSE score, we found that cognitive decline was significantly associated with low intakes of carotene, vitamin B 2 , pantothenate, calcium and green vegetables. Multiple logistic regression analysis showed that intakes of nutrients and green vegetables predicted cognitive decline after adjusting for age, body mass index, glycated hemoglobin levels, baseline MMSE score, and incident stroke during the follow up. These findings suggest that sufficient intakes of carotene, vitamin B 2 , pantothenate, calcium and vegetables could help prevent cognitive decline among elderly men with diabetes mellitus. Geriatr Gerontol Int 2017; 17: 1168-1175. © 2016 Japan Geriatrics Society.

Predictors of cognitive impairment assessed by Mini Mental State Examination in community-dwelling older adults: relevance of the step test.

PubMed

Muscari, Antonio; Spiller, Ilaria; Bianchi, Giampaolo; Fabbri, Elisa; Forti, Paola; Magalotti, Donatella; Pandolfi, Paolo; Zoli, Marco

2018-07-15

Several predictors of cognitive impairment assessed by Mini Mental State Examination (MMSE) have previously been identified. However, which predictors are the most relevant and what is their effect on MMSE categories remains unclear. Cross-sectional and longitudinal study using data from 1116 older adults (72.6 ± 5.6 years, 579 female), 350 of whom were followed for 7 years. At baseline, the following variables were collected: personal data, marital status, occupation, anthropometric measures, risk factors, previous cardiovascular events, self-rated health and physical activity during the last week. Furthermore, routine laboratory tests, abdominal echography and a step test (with measurement of the time needed to ascend and descend two steps 20 times) were performed. The associations of these variables with cross-sectional cognitive deficit (MMSE < 24) and longitudinal cognitive decline (decrease of MMSE score over 7 years of follow-up) were investigated using logistic regression models. Cross-sectional cognitive deficit was independently associated with school education ≤ 5 years, prolonged step test duration, having been blue collar or housewife (P ≤ 0.0001 for all) and, with lower significance, with advanced age, previous stroke and poor recent physical activity (P < 0.05). Longitudinal cognitive decline was mainly associated with step test duration (P = 0.0001) and diastolic blood pressure (P = 0.0002). The MMSE categories mostly associated with step test duration were orientation, attention, calculation and language, while memory appeared to be poorly or not affected. In our cohort of older adults, step test duration was the most relevant predictor of cognitive impairment. Copyright © 2018 Elsevier Inc. All rights reserved.

Mental and physical activities delay cognitive decline in older persons with dementia.

PubMed

Cheng, Sheung-Tak; Chow, Pizza K; Song, You-Qiang; Yu, Edwin C S; Chan, Alfred C M; Lee, Tatia M C; Lam, John H M

2014-01-01

To examine the effects of cognitive stimulation (mahjong) and physical exercise (tai chi [TC]) on cognitive performance in persons with dementia. Cluster-randomized open-label controlled design. Nursing homes. One hundred ten residents, most of whom were cholinesterase-inhibitor naive. Inclusion criteria were Mini-Mental State Examination (MMSE) = 10-24 and suffering from at least very mild dementia (Clinical Dementia Rating ≥ 0.5). Exclusion criteria were being bedbound, audio/visual impairment, regular activity participation before study, or contraindications for physical or group activities. Homes were randomized into three conditions (mahjong, TC, and simple handicrafts [control]). Activities were conducted three times weekly for 12 weeks. Primary outcome was MMSE. Secondary outcomes were immediate/delayed recall, categorical fluency, and digit span. Various biological risk factors, including apolipoprotein E ε4 allele, were included as covariates. Measures were collected at 0 (baseline), 3 (posttreatment), 6, and 9 months. Intent-to-treat analyses were performed using mixed-effects regression. Mahjong's effect varied by time for MMSE, delayed recall, and forward digit span. TC had similar effects but not for delayed recall. The typical pattern was that control participants deteriorated while mahjong and TC participants maintained their abilities over time, leading to enlarged treatment effects as time progressed. By 9 months, mahjong and TC differed from control by 4.5 points (95% confidence interval: 2.0-6.9; d = 0.48) and 3.7 points (95% confidence interval: 1.4-6.0; d = 0.40), respectively, on MMSE. No treatment effects were observed for immediate recall and backward digit span. Mahjong and TC can preserve functioning or delay decline in certain cognitive domains, even in those with significant cognitive impairment. Copyright © 2014 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

The traveling salesman problem as a new screening test in early Alzheimer's disease: an exploratory study. Visual problem-solving in AD.

PubMed

De Vreese, Luc Pieter; Pradelli, Samantha; Massini, Giulia; Buscema, Massimo; Savarè, Rita; Grossi, Enzo

2005-12-01

In the clinical setting, brief general mental status tests tend to detect early-stage Alzheimer's disease (AD) less well than more specific cognitive tests. Some preliminary information was collected on the diagnostic accuracy of the Traveling Salesman Problem (TSP) compared with the Mini-Mental State Examination (MMSE) in recognizing early AD from normal aging. Fifteen AD outpatients (mean +/- SD MMSE: 24.45 +/- 2.61) and 30 age- and education-matched controls were submitted in a single blind protocol to a paper-and-pencil visually-presented version of the TSP, containing a random array of 30 points (TSP30). The task consisted of drawing the shortest continuous path, passing through each point once and only once, and returning to the starting point. Path lengths for subjects' solutions were computed and compared with the optimal solution given by a specific evolutionary algorithm called GenD. TP30 discriminated significantly better between AD subjects and controls (ROC curve AUC = 0.976; 95% CI 0.94-1.01) compared with the MMSE corrected for age and education (ROC curve AUC = 0.877; 95% CI 0.74-1.005). A path length of 478.2354, taken as "cut-off point", classified correctly subjects with a sensitivity of 93.3% and a specificity of 99.3%, whereas a score corrected for age and education of 25.85 on the MMSE had a sensitivity of 73.3% and a specificity of 96.7%. The TSP seems to be particularly sensitive to early AD and independent of patient's age and educational level. The high diagnostic ability, simplicity, and independence of age and education make the TSP promising as a screening test for early AD.

Association between exercise habits and subcortical gray matter volumes in healthy elderly people: A population-based study in Japan.

PubMed

Yamamoto, Mikie; Wada-Isoe, Kenji; Yamashita, Fumio; Nakashita, Satoko; Kishi, Masafumi; Tanaka, Kenichiro; Yamawaki, Mika; Nakashima, Kenji

2017-06-01

The relationship between exercise and subcortical gray matter volume is not well understood in the elderly population, although reports indicate that exercise may prevent cortical gray matter atrophy. To elucidate this association in the elderly, we measured subcortical gray matter volume and correlated this with volumes to exercise habits in a community-based cohort study in Japan. Subjects without mild cognitive impairment or dementia (n = 280, 35% male, mean age 73.1 ± 5.9 years) were evaluated using the Mini-Mental State Examination (MMSE), an exercise habit questionnaire, and brain magnetic resonance imaging. Subcortical gray matter volume was compared between groups based on the presence/absence of exercise habits. The MMSE was re-administered 3 years after the baseline examination. Ninety-one subjects (32.5%) reported exercise habits (exercise group), and 189 subjects (67.5%) reported no exercise habits (non-exercise group). Volumetric analysis revealed that the volumes in the exercise group were greater in the left hippocampus (p = 0.042) and bilateral nucleus accumbens (left, p = 0.047; right, p = 0.007) compared to those of the non-exercise group. Among the 195 subjects who received a follow-up MMSE examination, the normalized intra-cranial volumes of the left nucleus accumbens (p = 0.004) and right amygdala (p = 0.014)showed significant association with a decline in the follow-up MMSE score. Subjects with exercise habits show larger subcortical gray matter volumes than subjects without exercise habits in community-dwelling elderly subjects in Japan. Specifically, the volume of the nucleus accumbens correlates with both exercise habits and cognitive preservation.

Walking stabilizes cognitive functioning in Alzheimer's disease (AD) across one year.

PubMed

Winchester, J; Dick, M B; Gillen, D; Reed, B; Miller, B; Tinklenberg, J; Mungas, D; Chui, H; Galasko, D; Hewett, L; Cotman, C W

2013-01-01

AD is a public health epidemic, which seriously impacts cognition, mood and daily activities; however, one type of activity, exercise, has been shown to alter these states. Accordingly, we sought to investigate the relationship between exercise and mood, in early-stage AD patients (N=104) from California, over a 1-year period. Patients completed the Mini-Mental State Examination (MMSE), Geriatric Depression Scale (GDS), and Blessed-Roth Dementia Rating Scale (BRDRS), while their caregivers completed the Yale Physical Activity Survey (YALE), Profile of Mood States (POMS), the Neuropsychiatric Inventory (NPI) and Functional Abilities Questionnaire (FAQ). Approximately half of the participants were female, from a variety of ethnic groups (Caucasian=69.8%; Latino/Hispanic Americans=20.1%). Our results demonstrated that the patients spent little time engaged in physical activity in general, their overall activity levels decreased over time, and this was paired with a change in global cognition (e.g., MMSE total score) and affect/mood (e.g., POMS score). Patients were parsed into Active and Sedentary groups based on their Yale profiles, with Active participants engaged in walking activities, weekly, over 1 year. Here, Sedentary patients had a significant decline in MMSE scores, while the Active patients had an attenuation in global cognitive decline. Importantly, among the Active AD patients, those individuals who engaged in walking for more than 2 h/week had a significant improvement in MMSE scores. Structured clinical trials which seek to increase the amount of time AD patients were engaged in walking activities and evaluate the nature and scope of beneficial effects in the brain are warranted. Copyright © 2012. Published by Elsevier Ireland Ltd.

Stimulus Equalization: Temporary Reduction of Stimulus Complexity to Facilitate Discrimination Learning.

ERIC Educational Resources Information Center

Hoko, J. Aaron; LeBlanc, Judith M.

1988-01-01

Because disabled learners may profit from procedures using gradual stimulus change, this study utilized a microcomputer to investigate the effectiveness of stimulus equalization, an error reduction procedure involving an abrupt but temporary reduction of dimensional complexity. The procedure was found to be generally effective and implications for…

Chemical composition of cosmic rays with Z greater than or equal to 30 and E greater than or equal to 325 MeV/N

NASA Technical Reports Server (NTRS)

Binns, W. R.; Fernandez, J. I.; Israel, M. H.; Klarmann, J.; Maehl, R. C.; Mewaldt, R. A.

1974-01-01

Results are presented on the chemical composition of VVH cosmic rays from a series of six high-altitude balloon flights of a large-area, high-resolution electronic detector. The charge composition in the 32 less than or equal to Z less than or equal to 45 interval is found to be inconsistent with S-process nucleosynthesis. The energy spectrum of particles with Z greater than or equal to 32 between 600 and 1500 MeV/N at the top of the atmosphere is measured and is found to be consistent with the 25 less than or equal to Z less than or equal to 27 group within experimental error.

New spatial diversity equalizer based on PLL

NASA Astrophysics Data System (ADS)

Rao, Wei

2011-10-01

A new Spatial Diversity Equalizer (SDE) based on phase-locked loop (PLL) is proposed to overcome the inter-symbol interference (ISI) and phase rotations simultaneously in the digital communication system. The proposed SDE consists of equal gain combining technique based on a famous blind equalization algorithm constant modulus algorithm (CMA) and a PLL. Compared with conventional SDE, the proposed SDE has not only faster convergence rate and lower residual error but also the ability to recover carrier phase rotation. The efficiency of the method is proved by computer simulation.

Cellular traction force recovery: An optimal filtering approach in two-dimensional Fourier space.

PubMed

Huang, Jianyong; Qin, Lei; Peng, Xiaoling; Zhu, Tao; Xiong, Chunyang; Zhang, Youyi; Fang, Jing

2009-08-21

Quantitative estimation of cellular traction has significant physiological and clinical implications. As an inverse problem, traction force recovery is essentially susceptible to noise in the measured displacement data. For traditional procedure of Fourier transform traction cytometry (FTTC), noise amplification is accompanied in the force reconstruction and small tractions cannot be recovered from the displacement field with low signal-noise ratio (SNR). To improve the FTTC process, we develop an optimal filtering scheme to suppress the noise in the force reconstruction procedure. In the framework of the Wiener filtering theory, four filtering parameters are introduced in two-dimensional Fourier space and their analytical expressions are derived in terms of the minimum-mean-squared-error (MMSE) optimization criterion. The optimal filtering approach is validated with simulations and experimental data associated with the adhesion of single cardiac myocyte to elastic substrate. The results indicate that the proposed method can highly enhance SNR of the recovered forces to reveal tiny tractions in cell-substrate interaction.

An Energy-Efficient Compressive Image Coding for Green Internet of Things (IoT).

PubMed

Li, Ran; Duan, Xiaomeng; Li, Xu; He, Wei; Li, Yanling

2018-04-17

Aimed at a low-energy consumption of Green Internet of Things (IoT), this paper presents an energy-efficient compressive image coding scheme, which provides compressive encoder and real-time decoder according to Compressive Sensing (CS) theory. The compressive encoder adaptively measures each image block based on the block-based gradient field, which models the distribution of block sparse degree, and the real-time decoder linearly reconstructs each image block through a projection matrix, which is learned by Minimum Mean Square Error (MMSE) criterion. Both the encoder and decoder have a low computational complexity, so that they only consume a small amount of energy. Experimental results show that the proposed scheme not only has a low encoding and decoding complexity when compared with traditional methods, but it also provides good objective and subjective reconstruction qualities. In particular, it presents better time-distortion performance than JPEG. Therefore, the proposed compressive image coding is a potential energy-efficient scheme for Green IoT.

Adaptive Window Zero-Crossing-Based Instantaneous Frequency Estimation

NASA Astrophysics Data System (ADS)

Sekhar, S. Chandra; Sreenivas, TV

2004-12-01

We address the problem of estimating instantaneous frequency (IF) of a real-valued constant amplitude time-varying sinusoid. Estimation of polynomial IF is formulated using the zero-crossings of the signal. We propose an algorithm to estimate nonpolynomial IF by local approximation using a low-order polynomial, over a short segment of the signal. This involves the choice of window length to minimize the mean square error (MSE). The optimal window length found by directly minimizing the MSE is a function of the higher-order derivatives of the IF which are not available a priori. However, an optimum solution is formulated using an adaptive window technique based on the concept of intersection of confidence intervals. The adaptive algorithm enables minimum MSE-IF (MMSE-IF) estimation without requiring a priori information about the IF. Simulation results show that the adaptive window zero-crossing-based IF estimation method is superior to fixed window methods and is also better than adaptive spectrogram and adaptive Wigner-Ville distribution (WVD)-based IF estimators for different signal-to-noise ratio (SNR).

Potential Seasonal Terrestrial Water Storage Monitoring from GPS Vertical Displacements: A Case Study in the Lower Three-Rivers Headwater Region, China.

PubMed

Zhang, Bao; Yao, Yibin; Fok, Hok Sum; Hu, Yufeng; Chen, Qiang

2016-09-19

This study uses the observed vertical displacements of Global Positioning System (GPS) time series obtained from the Crustal Movement Observation Network of China (CMONOC) with careful pre- and post-processing to estimate the seasonal crustal deformation in response to the hydrological loading in lower three-rivers headwater region of southwest China, followed by inferring the annual EWH changes through geodetic inversion methods. The Helmert Variance Component Estimation (HVCE) and the Minimum Mean Square Error (MMSE) criterion were successfully employed. The GPS inferred EWH changes agree well qualitatively with the Gravity Recovery and Climate Experiment (GRACE)-inferred and the Global Land Data Assimilation System (GLDAS)-inferred EWH changes, with a discrepancy of 3.2-3.9 cm and 4.8-5.2 cm, respectively. In the research areas, the EWH changes in the Lancang basin is larger than in the other regions, with a maximum of 21.8-24.7 cm and a minimum of 3.1-6.9 cm.

Maximum correntropy square-root cubature Kalman filter with application to SINS/GPS integrated systems.

PubMed

Liu, Xi; Qu, Hua; Zhao, Jihong; Yue, Pengcheng

2018-05-31

For a nonlinear system, the cubature Kalman filter (CKF) and its square-root version are useful methods to solve the state estimation problems, and both can obtain good performance in Gaussian noises. However, their performances often degrade significantly in the face of non-Gaussian noises, particularly when the measurements are contaminated by some heavy-tailed impulsive noises. By utilizing the maximum correntropy criterion (MCC) to improve the robust performance instead of traditional minimum mean square error (MMSE) criterion, a new square-root nonlinear filter is proposed in this study, named as the maximum correntropy square-root cubature Kalman filter (MCSCKF). The new filter not only retains the advantage of square-root cubature Kalman filter (SCKF), but also exhibits robust performance against heavy-tailed non-Gaussian noises. A judgment condition that avoids numerical problem is also given. The results of two illustrative examples, especially the SINS/GPS integrated systems, demonstrate the desirable performance of the proposed filter. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

Local Observability Analysis of Star Sensor Installation Errors in a SINS/CNS Integration System for Near-Earth Flight Vehicles

PubMed Central

Yang, Yanqiang; Zhang, Chunxi; Lu, Jiazhen

2017-01-01

Strapdown inertial navigation system/celestial navigation system (SINS/CNS) integrated navigation is a fully autonomous and high precision method, which has been widely used to improve the hitting accuracy and quick reaction capability of near-Earth flight vehicles. The installation errors between SINS and star sensors have been one of the main factors that restrict the actual accuracy of SINS/CNS. In this paper, an integration algorithm based on the star vector observations is derived considering the star sensor installation error. Then, the star sensor installation error is accurately estimated based on Kalman Filtering (KF). Meanwhile, a local observability analysis is performed on the rank of observability matrix obtained via linearization observation equation, and the observable conditions are presented and validated. The number of star vectors should be greater than or equal to 2, and the times of posture adjustment also should be greater than or equal to 2. Simulations indicate that the star sensor installation error could be readily observable based on the maneuvering condition; moreover, the attitude errors of SINS are less than 7 arc-seconds. This analysis method and conclusion are useful in the ballistic trajectory design of near-Earth flight vehicles. PMID:28275211

Correlation between disease severity and brain electric LORETA tomography in Alzheimer's disease.

PubMed

Gianotti, Lorena R R; Künig, Gabriella; Lehmann, Dietrich; Faber, Pascal L; Pascual-Marqui, Roberto D; Kochi, Kieko; Schreiter-Gasser, Ursula

2007-01-01

To compare EEG power spectra and LORETA-computed intracortical activity between Alzheimer's disease (AD) patients and healthy controls, and to correlate the results with cognitive performance in the AD group. Nineteen channel resting EEG was recorded in 21 mild to moderate AD patients and in 23 controls. Power spectra and intracortical LORETA tomography were computed in seven frequency bands and compared between groups. In the AD patients, the EEG results were correlated with cognitive performance (Mini Mental State Examination, MMSE). AD patients showed increased power in EEG delta and theta frequency bands, and decreased power in alpha2, beta1, beta2 and beta3. LORETA specified that increases and decreases of power affected different cortical areas while largely sparing prefrontal cortex. Delta power correlated negatively and alpha1 power positively with the AD patients' MMSE scores; LORETA tomography localized these correlations in left temporo-parietal cortex. The non-invasive EEG method of LORETA localized pathological cortical activity in our mild to moderate AD patients in agreement with the literature, and yielded striking correlations between EEG delta and alpha1 activity and MMSE scores in left temporo-parietal cortex. The present data support the hypothesis of an asymmetrical progression of the Alzheimer's disease.

Effects of multisensory stimulation on cognition, depression and anxiety levels of mildly-affected Alzheimer's patients.

PubMed

Ozdemir, Leyla; Akdemir, Nuran

2009-08-15

The purpose of this study was to investigate and assess the effects of musical therapy, painting inanimate-animate object pictures, and orientation to time-place-person interventions on the cognitive state, depression, and anxiety levels of mildly-affected Alzheimer's patients. The study using a quasi-experimental design was conducted with 27 mildly-affected Alzheimer's patients. The effects of the multisensory stimulation were evaluated with the "Mini Mental State Examination," the "Geriatric Depression Scale," and the "Beck Anxiety Scale." All of these were administered one day prior to beginning the study, immediately after its completion, and three weeks thereafter. A significant negative correlation was determined to exist between the MMSE-depression scores and MMSE-anxiety scores; the correlation between the depression-anxiety scores, on the other hand, had a positive significance. The shifts over time in the MMSE, depression and anxiety scores were significant. The primary conclusion of the study is that the multisensory stimulation method applied to mildly-affected Alzheimer's patients had a positive effect on their cognitive state, depression, and anxiety, and that this effect continued for three weeks following completion of the study intervention, with a tendency to decline progressively.

The relation of education, occupation, and cognitive activity to cognitive status in old age: the role of physical frailty.

PubMed

Ihle, Andreas; Gouveia, Élvio R; Gouveia, Bruna R; Freitas, Duarte L; Jurema, Jefferson; Odim, Angenay P; Kliegel, Matthias

2017-09-01

It remains unclear so far whether the role of cognitive reserve may differ between physically frail compared to less frail individuals. Therefore, the present study set out to investigate the relation of key markers of cognitive reserve to cognitive status in old age and its interplay with physical frailty in a large sample of older adults. We assessed Mini-Mental State Examination (MMSE) in 701 older adults. We measured grip strength as indicator of physical frailty and interviewed individuals on their education, past occupation, and cognitive leisure activity. Greater grip strength, longer education, higher cognitive level of job, and greater engaging in cognitive leisure activity were significantly related to higher MMSE scores. Moderation analyses showed that the relations of education, cognitive level of job, and cognitive leisure activity to MMSE scores were significantly larger in individuals with lower, compared to those with greater grip strength. Cognitive status in old age may more strongly depend on cognitive reserve accumulated during the life course in physically frail (compared to less frail) older adults. These findings may be explained by cross-domain compensation effects in vulnerable individuals.

Identification of measurement differences between English and Spanish language versions of the Mini-Mental State Examination. Detecting differential item functioning using MIMIC modeling.

PubMed

Jones, Richard N

2006-11-01

Knowledge of the extent to which measurement of adult cognitive functioning differs between Spanish and English language administrations of the Mini-Mental State Examination (MMSE) is critical for inclusive, representative, and valid research of older adults in the United States. We sought to demonstrate the use of an item response theory (IRT) based structural equation model, that is, the MIMIC model (multiple indicators, multiple causes), to evaluate MMSE responses for evidence of differential item functioning (DIF) attributable to language of administration. We studied participants in a dementia case registry study (n = 1546), 42% of whom were examined with the Spanish language MMSE. Twelve of 21 items were identified as having significant uniform DIF. The 4 most discrepant included orientation to season, orientation to state, repeat phrase, and follow command. DIF accounted for two-thirds of the observed difference in underlying level of cognitive functioning between Spanish- and English-language administration groups. Failing to account for measurement differences may lead to spurious inferences regarding language group differences in level of underlying level of cognitive functioning. The MIMIC model can be used to detect and adjust for such measurement differences in substantive research.

The relationship between Piaget and cognitive levels in persons with Alzheimer's disease and related disorders.

PubMed

Matteson, M A; Linton, A D; Barnes, S J; Cleary, B L; Lichtenstein, M J

1996-02-01

Clinical observations and research studies have documented that people with Alzheimer's disease and related disorders (ADRD) appear to regress developmentally during the course of the disease. The purpose of this study was to prospectively determine the association between changes in Piaget levels of cognitive development and cognitive decline in nursing home residents in various stages of ADRD. Fifty-seven people were tested three times at yearly intervals, using the Folstein Mini-Mental State Exam to determine cognitive levels and a set of 14 Piaget tasks to determine cognitive developmental levels: 1) Formal Operations; 2) Concrete Operations; 3) Preoperational; and 4) Sensorimotor. Mean MMSE scores declined from 12.7 to 9.4, and there was a downward trend in Piaget levels over the study period. ANOVA showed significant differences (p < 0.0005, Years 1, 2, 3) in MMSE scores among all Piaget levels, and Spearman rho analysis showed significant correlations between Piaget levels and MMSE for each year (p < 0.0005, Years 1, 2, 3). The results suggest that there is a concurrent decline in cognitive developmental levels and cognition in people in various stages of Alzheimer's disease and related disorders.

Cortical connectivity and memory performance in cognitive decline: A study via graph theory from EEG data.

PubMed

Vecchio, F; Miraglia, F; Quaranta, D; Granata, G; Romanello, R; Marra, C; Bramanti, P; Rossini, P M

2016-03-01

Functional brain abnormalities including memory loss are found to be associated with pathological changes in connectivity and network neural structures. Alzheimer's disease (AD) interferes with memory formation from the molecular level, to synaptic functions and neural networks organization. Here, we determined whether brain connectivity of resting-state networks correlate with memory in patients affected by AD and in subjects with mild cognitive impairment (MCI). One hundred and forty-four subjects were recruited: 70 AD (MMSE Mini Mental State Evaluation 21.4), 50 MCI (MMSE 25.2) and 24 healthy subjects (MMSE 29.8). Undirected and weighted cortical brain network was built to evaluate graph core measures to obtain Small World parameters. eLORETA lagged linear connectivity as extracted by electroencephalogram (EEG) signals was used to weight the network. A high statistical correlation between Small World and memory performance was found. Namely, higher Small World characteristic in EEG gamma frequency band during the resting state, better performance in short-term memory as evaluated by the digit span tests. Such Small World pattern might represent a biomarker of working memory impairment in older people both in physiological and pathological conditions. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

High Sensitivity Cardiac Troponin T and Cognitive Function in the Oldest Old: The Leiden 85-Plus Study.

PubMed

Bertens, Anne Suzanne; Sabayan, Behnam; de Craen, Anton J M; Van der Mast, Roos C; Gussekloo, Jacobijn

2017-01-01

Impaired cardiac function has been related to accelerated cognitive decline in late-life. To investigate whether higher levels of high sensitivity cardiac troponin T (hs-cTnT), a sensitive marker for myocardial injury, are associated with worse cognitive function in the oldest old. In 455 participants of the population-based Leiden 85-plus Study, hs-cTnT was measured at 86 years. Cognitive function was measured annually during four years with the Mini-Mental State Examination (MMSE). Participants in the highest gender-specific tertile of hs-cTnT had a 2.0-point lower baseline MMSE score than participants in the lowest tertile (95% confidence interval (CI) (95% CI 0.73-3.3), and had a 0.58-point steeper annual decline in MMSE during follow-up (95% CI 0.06-1.1). The associations remained after adjusting for sociodemographic and cardiovascular risk factors excluding those without a history of overt cardiac disease. In a population-based sample of the oldest old, higher levels of hs-cTnT were associated with worse cognitive function and faster cognitive decline, independently from cardiovascular risk factors and a history of overt cardiac disease.

Changes in Tryptophan Catabolite (TRYCAT) Pathway Patterning Are Associated with Mild Impairments in Declarative Memory in Schizophrenia and Deficits in Semantic and Episodic Memory Coupled with Increased False-Memory Creation in Deficit Schizophrenia.

PubMed

Kanchanatawan, Buranee; Hemrungrojn, Solaphat; Thika, Supaksorn; Sirivichayakul, Sunee; Ruxrungtham, Kiat; Carvalho, André F; Geffard, Michel; Anderson, George; Maes, Michael

2018-06-01

Evidence indicates that schizophrenia and in particular negative symptoms and deficit schizophrenia are accompanied by neurocognitive impairments and changes in the patterning of the tryptophan catabolite (TRYCAT) pathway. This cross-sectional study was carried out to examine the associations between cognitive functions (as measured with Consortium to Establish a Registry for Alzheimer's disease (CERAD)) and TRYCAT pathway patterning in patients with (n = 40) and without (n = 40) deficit schizophrenia and normal controls (n = 40). Cognitive measures were assessed with the Verbal Fluency Test (VFT), Boston Naming Test (BNT), Mini-Mental State Examination (MMSE), Word List Memory (WLM), Constructional Praxis, Word List Recall (WLRecall), and Word List Recognition (WLRecognition), while TRYCAT measurements assessed the IgA/IgM responses to noxious TRYCATs, namely quinolinic acid (QA), 3-OH-kynurenine (3HK), picolinic acid (PA), and xanthurenic (XA) acid, and more protective (PRO) TRYCATs, including kynurenic acid (KA) and anthranilic acid (AA). IgA NOX/PRO, IgM KA/3HK, and IgA/IgM NOX/PRO ratios were computed. Schizophrenia was accompanied by lower VFT and WLM, while BNT (dysnomia) and MMSE are significantly lower in multiple- than first-episode schizophrenia. Deficit schizophrenia is strongly associated with worse outcomes on VFT, MMSE, WLM, WLRecall, WLRecognition, and delayed recall savings and increased false memories. Around 40-50% of the variance in negative symptoms' scores was explained by VFT, WLM, WLRecall, and MMSE. Increases in IgA NOX/PRO, IgM KA/3HK, and/or IgA/IgM NOX/PRO ratios were associated with impairments in VFT, BNT, MMSE, WLM, WLRecall, WLRecognition, and false-memory creation. In conclusion, nondeficit schizophrenia is accompanied by mild memory impairments, while disease progression is accompanied by broader cognitive impairments. Deficit schizophrenia and negative symptoms are strongly associated with deficits in working memory, delayed recall and recognition, and increased false-memory creation. These cognitive impairments and memory deficits are in part explained by increased production and/or attenuated regulation of TRYCATs with neurotoxic, excitotoxic, immune-inflammatory, oxidative, and nitrosative potential, which may contribute to neuroprogression.

Research on Signature Verification Method Based on Discrete Fréchet Distance

NASA Astrophysics Data System (ADS)

Fang, J. L.; Wu, W.

2018-05-01

This paper proposes a multi-feature signature template based on discrete Fréchet distance, which breaks through the limitation of traditional signature authentication using a single signature feature. It solves the online handwritten signature authentication signature global feature template extraction calculation workload, signature feature selection unreasonable problem. In this experiment, the false recognition rate (FAR) and false rejection rate (FRR) of the statistical signature are calculated and the average equal error rate (AEER) is calculated. The feasibility of the combined template scheme is verified by comparing the average equal error rate of the combination template and the original template.

Decision feedback equalizer for holographic data storage.

PubMed

Kim, Kyuhwan; Kim, Seung Hun; Koo, Gyogwon; Seo, Min Seok; Kim, Sang Woo

2018-05-20

Holographic data storage (HDS) has attracted much attention as a next-generation storage medium. Because HDS suffers from two-dimensional (2D) inter-symbol interference (ISI), the partial-response maximum-likelihood (PRML) method has been studied to reduce 2D ISI. However, the PRML method has various drawbacks. To solve the problems, we propose a modified decision feedback equalizer (DFE) for HDS. To prevent the error propagation problem, which is a typical problem in DFEs, we also propose a reliability factor for HDS. Various simulations were executed to analyze the performance of the proposed methods. The proposed methods showed fast processing speed after training, superior bit error rate performance, and consistency.

A Stationary North-Finding Scheme for an Azimuth Rotational IMU Utilizing a Linear State Equality Constraint

PubMed Central

Yu, Huapeng; Zhu, Hai; Gao, Dayuan; Yu, Meng; Wu, Wenqi

2015-01-01

The Kalman filter (KF) has always been used to improve north-finding performance under practical conditions. By analyzing the characteristics of the azimuth rotational inertial measurement unit (ARIMU) on a stationary base, a linear state equality constraint for the conventional KF used in the fine north-finding filtering phase is derived. Then, a constrained KF using the state equality constraint is proposed and studied in depth. Estimation behaviors of the concerned navigation errors when implementing the conventional KF scheme and the constrained KF scheme during stationary north-finding are investigated analytically by the stochastic observability approach, which can provide explicit formulations of the navigation errors with influencing variables. Finally, multiple practical experimental tests at a fixed position are done on a postulate system to compare the stationary north-finding performance of the two filtering schemes. In conclusion, this study has successfully extended the utilization of the stochastic observability approach for analytic descriptions of estimation behaviors of the concerned navigation errors, and the constrained KF scheme has demonstrated its superiority over the conventional KF scheme for ARIMU stationary north-finding both theoretically and practically. PMID:25688588

A successive overrelaxation iterative technique for an adaptive equalizer

NASA Technical Reports Server (NTRS)

Kosovych, O. S.

1973-01-01

An adaptive strategy for the equalization of pulse-amplitude-modulated signals in the presence of intersymbol interference and additive noise is reported. The successive overrelaxation iterative technique is used as the algorithm for the iterative adjustment of the equalizer coefficents during a training period for the minimization of the mean square error. With 2-cyclic and nonnegative Jacobi matrices substantial improvement is demonstrated in the rate of convergence over the commonly used gradient techniques. The Jacobi theorems are also extended to nonpositive Jacobi matrices. Numerical examples strongly indicate that the improvements obtained for the special cases are possible for general channel characteristics. The technique is analytically demonstrated to decrease the mean square error at each iteration for a large range of parameter values for light or moderate intersymbol interference and for small intervals for general channels. Analytically, convergence of the relaxation algorithm was proven in a noisy environment and the coefficient variance was demonstrated to be bounded.

Detectable changes in physical performance measures in elderly African Americans.

PubMed

Mangione, Kathleen Kline; Craik, Rebecca L; McCormick, Alyson A; Blevins, Heather L; White, Meaghan B; Sullivan-Marx, Eileen M; Tomlinson, James D

2010-06-01

African American older adults have higher rates of self-reported disability and lower physical performance scores compared with white older adults. Measures of physical performance are used to predict future morbidity and to determine the effect of exercise. Characteristics of performance measures are not known for African American older adults. The purpose of this study was to estimate the standard error of measurement (SEM) and minimal detectable change (MDC) for the Short Physical Performance Battery (SPPB), Timed "Up & Go" Test (TUG) time, free gait speed, fast gait speed, and Six-Minute Walk Test (6MWT) distance in frail African American adults. This observational measurement study used a test-retest design. Individuals were tested 2 times over a 1-week period. Demographic data collected included height, weight, number of medications, assistive device use, and Mini-Mental Status Examination (MMSE) scores. Participants then completed the 5 physical performance tests. Fifty-two participants (mean age=78 years) completed the study. The average MMSE score was 25 points, and the average body mass index was 29.4 kg/m(2). On average, participants took 7 medications, and the majority used assistive devices. Intraclass correlation coefficients (ICC [2,1]) were greater than .90, except for the SPPB score (ICC=.81). The SEMs were 1.2 points for the SPPB, 1.7 seconds for the TUG, 0.08 m/s for free gait speed, 0.09 m/s for fast gait speed, and 28 m for 6MWT distance. The MDC values were 2.9 points for the SPPB, 4 seconds for the TUG, 0.19 m/s for free gait speed, 0.21 m/s for fast gait speed, and 65 m for 6MWT distance. The entire sample was from an urban area. The SEMs were similar to previously reported values and can be used when working with African American and white older adults. Estimates of MDC were calculated to assist in clinical interpretation.

Performance-based functional assessment in older hospitalized patients: feasibility and clinical correlates.

PubMed

Volpato, Stefano; Cavalieri, Margherita; Guerra, Gianluca; Sioulis, Fotini; Ranzini, Monica; Maraldi, Cinzia; Fellin, Renato; Guralnik, Jack M

2008-12-01

Functional evaluation is a cornerstone of multidimensional geriatric assessment; however, little is known of the clinical value of standardized performance-based assessment in the acute care setting. The aim of this study was to evaluate the clinical correlates and short-term predictive value of the Short Physical Performance Battery (SPPB) in older patients admitted to the hospital for an acute medical event. We enrolled 92 women and men 65 years old or older who were able to walk, who had a Mini-Mental State Examination (MMSE) score > or =18, and who were admitted to the hospital with a clinical diagnosis of congestive heart failure, pneumonia, chronic obstructive pulmonary disease (COPD), or minor stroke. The SPPB was assessed at hospital admission and discharge. Self-report functional assessment included basic activities of daily living (ADL) and instrumental activities of daily living (IADL). Spearman's rank correlation coefficients and multivariable linear regression analyses were used to study the association of SPPB score and functional and clinical characteristics, including length of hospital stay. The mean age was 77.7 years (range 65-94 years), 49% were female, 64.1% had congestive heart failure, 16% COPD, 13.1% pneumonia, and 6.5% minor stroke. At hospital admission the mean SPPB score was 6.0 +/- 2.7. SPPB scores were inversely correlated with age, the severity of the index disease, and IADL and ADL difficulty 2 weeks before hospital admission (p <.01), and were directly correlated with MMSE score (p =.002). On average, SPPB score increased 1 point (+0.97, standard error of the mean = 0.2; p for paired t test <.001) from baseline to hospital discharge assessment. After adjustment for potential confounders, baseline SPPB score was significantly associated with the length of hospital stay (p <.007). In older acute care inpatients, SPPB is a valid indicator of functional and clinical status. SPPB score at hospital admission is an independent predictor of the length of hospital stay.

Binaural noise reduction via cue-preserving MMSE filter and adaptive-blocking-based noise PSD estimation

NASA Astrophysics Data System (ADS)

Azarpour, Masoumeh; Enzner, Gerald

2017-12-01

Binaural noise reduction, with applications for instance in hearing aids, has been a very significant challenge. This task relates to the optimal utilization of the available microphone signals for the estimation of the ambient noise characteristics and for the optimal filtering algorithm to separate the desired speech from the noise. The additional requirements of low computational complexity and low latency further complicate the design. A particular challenge results from the desired reconstruction of binaural speech input with spatial cue preservation. The latter essentially diminishes the utility of multiple-input/single-output filter-and-sum techniques such as beamforming. In this paper, we propose a comprehensive and effective signal processing configuration with which most of the aforementioned criteria can be met suitably. This relates especially to the requirement of efficient online adaptive processing for noise estimation and optimal filtering while preserving the binaural cues. Regarding noise estimation, we consider three different architectures: interaural (ITF), cross-relation (CR), and principal-component (PCA) target blocking. An objective comparison with two other noise PSD estimation algorithms demonstrates the superiority of the blocking-based noise estimators, especially the CR-based and ITF-based blocking architectures. Moreover, we present a new noise reduction filter based on minimum mean-square error (MMSE), which belongs to the class of common gain filters, hence being rigorous in terms of spatial cue preservation but also efficient and competitive for the acoustic noise reduction task. A formal real-time subjective listening test procedure is also developed in this paper. The proposed listening test enables a real-time assessment of the proposed computationally efficient noise reduction algorithms in a realistic acoustic environment, e.g., considering time-varying room impulse responses and the Lombard effect. The listening test outcome reveals that the signals processed by the blocking-based algorithms are significantly preferred over the noisy signal in terms of instantaneous noise attenuation. Furthermore, the listening test data analysis confirms the conclusions drawn based on the objective evaluation.

5 CFR 1604.6 - Error correction.

Code of Federal Regulations, 2010 CFR

2010-01-01

... a service member requesting that a TSP contribution be deducted from bonus pay. Within 30 days of... times the number of months it would take for the service member to earn basic pay equal to the dollar... less than twice the number of months it would take for the service member to earn basic pay equal to...

Single Carrier with Frequency Domain Equalization for Synthetic Aperture Underwater Acoustic Communications

PubMed Central

He, Chengbing; Xi, Rui; Wang, Han; Jing, Lianyou; Shi, Wentao; Zhang, Qunfei

2017-01-01

Phase-coherent underwater acoustic (UWA) communication systems typically employ multiple hydrophones in the receiver to achieve spatial diversity gain. However, small underwater platforms can only carry a single transducer which can not provide spatial diversity gain. In this paper, we propose single-carrier with frequency domain equalization (SC-FDE) for phase-coherent synthetic aperture acoustic communications in which a virtual array is generated by the relative motion between the transmitter and the receiver. This paper presents synthetic aperture acoustic communication results using SC-FDE through data collected during a lake experiment in January 2016. The performance of two receiver algorithms is analyzed and compared, including the frequency domain equalizer (FDE) and the hybrid time frequency domain equalizer (HTFDE). The distances between the transmitter and the receiver in the experiment were about 5 km. The bit error rate (BER) and output signal-to-noise ratio (SNR) performances with different receiver elements and transmission numbers were presented. After combining multiple transmissions, error-free reception using a convolution code with a data rate of 8 kbps was demonstrated. PMID:28684683

Random access to mobile networks with advanced error correction

NASA Technical Reports Server (NTRS)

Dippold, Michael

1990-01-01

A random access scheme for unreliable data channels is investigated in conjunction with an adaptive Hybrid-II Automatic Repeat Request (ARQ) scheme using Rate Compatible Punctured Codes (RCPC) Forward Error Correction (FEC). A simple scheme with fixed frame length and equal slot sizes is chosen and reservation is implicit by the first packet transmitted randomly in a free slot, similar to Reservation Aloha. This allows the further transmission of redundancy if the last decoding attempt failed. Results show that a high channel utilization and superior throughput can be achieved with this scheme that shows a quite low implementation complexity. For the example of an interleaved Rayleigh channel and soft decision utilization and mean delay are calculated. A utilization of 40 percent may be achieved for a frame with the number of slots being equal to half the station number under high traffic load. The effects of feedback channel errors and some countermeasures are discussed.

A theory for predicting composite laminate warpage resulting from fabrication

NASA Technical Reports Server (NTRS)

Chamis, C. C.

1975-01-01

Linear laminate theory is used in conjunction with the moment-curvature relationship to derive equations for predicting end deflections due to warpage without solving the coupled fourth-order partial differential equations of the plate. Using these equations, it is found that a 1 deg error in the orientation angle of one ply is sufficient to produce warpage end deflection equal to two laminate thicknesses in a 10 inch by 10 inch laminate made from 8-ply Mod-I/epoxy. From a sensitivity analysis on the governing parameters, it is found that a 3 deg fiber migration or a void volume ratio of three percent in some plies is sufficient to produce laminate warpage corner deflection equal to several laminate thicknesses. Tabular and graphical data are presented which can be used to identify possible errors contributing to laminate warpage and/or to obtain an a priori assessment when unavoidable errors during fabrication are anticipated.

English speech sound development in preschool-aged children from bilingual English-Spanish environments.

PubMed

Gildersleeve-Neumann, Christina E; Kester, Ellen S; Davis, Barbara L; Peña, Elizabeth D

2008-07-01

English speech acquisition by typically developing 3- to 4-year-old children with monolingual English was compared to English speech acquisition by typically developing 3- to 4-year-old children with bilingual English-Spanish backgrounds. We predicted that exposure to Spanish would not affect the English phonetic inventory but would increase error frequency and type in bilingual children. Single-word speech samples were collected from 33 children. Phonetically transcribed samples for the 3 groups (monolingual English children, English-Spanish bilingual children who were predominantly exposed to English, and English-Spanish bilingual children with relatively equal exposure to English and Spanish) were compared at 2 time points and for change over time for phonetic inventory, phoneme accuracy, and error pattern frequencies. Children demonstrated similar phonetic inventories. Some bilingual children produced Spanish phonemes in their English and produced few consonant cluster sequences. Bilingual children with relatively equal exposure to English and Spanish averaged more errors than did bilingual children who were predominantly exposed to English. Both bilingual groups showed higher error rates than English-only children overall, particularly for syllable-level error patterns. All language groups decreased in some error patterns, although the ones that decreased were not always the same across language groups. Some group differences of error patterns and accuracy were significant. Vowel error rates did not differ by language group. Exposure to English and Spanish may result in a higher English error rate in typically developing bilinguals, including the application of Spanish phonological properties to English. Slightly higher error rates are likely typical for bilingual preschool-aged children. Change over time at these time points for all 3 groups was similar, suggesting that all will reach an adult-like system in English with exposure and practice.

Equalization of nonlinear transmission impairments by maximum-likelihood-sequence estimation in digital coherent receivers.

PubMed

Khairuzzaman, Md; Zhang, Chao; Igarashi, Koji; Katoh, Kazuhiro; Kikuchi, Kazuro

2010-03-01

We describe a successful introduction of maximum-likelihood-sequence estimation (MLSE) into digital coherent receivers together with finite-impulse response (FIR) filters in order to equalize both linear and nonlinear fiber impairments. The MLSE equalizer based on the Viterbi algorithm is implemented in the offline digital signal processing (DSP) core. We transmit 20-Gbit/s quadrature phase-shift keying (QPSK) signals through a 200-km-long standard single-mode fiber. The bit-error rate performance shows that the MLSE equalizer outperforms the conventional adaptive FIR filter, especially when nonlinear impairments are predominant.

Breaches of health information: are electronic records different from paper records?

PubMed

Sade, Robert M

2010-01-01

Breaches of electronic medical records constitute a type of healthcare error, but should be considered separately from other types of errors because the national focus on the security of electronic data justifies special treatment of medical information breaches. Guidelines for protecting electronic medical records should be applied equally to paper medical records.

Predicted Blood Glucose from Insulin Administration Based on Values from Miscoded Glucose Meters

PubMed Central

Raine, Charles H.; Pardo, Scott; Parkes, Joan Lee

2008-01-01

Objectives The proper use of many types of self-monitored blood glucose (SMBG) meters requires calibration to match strip code. Studies have demonstrated the occurrence and impact on insulin dose of coding errors with SMBG meters. This paper reflects additional analyses performed with data from Raine et al. (JDST, 2:205–210, 2007). It attempts to relate potential insulin dose errors to possible adverse blood glucose outcomes when glucose meters are miscoded. Methods Five sets of glucose meters were used. Two sets of meters were autocoded and therefore could not be miscoded, and three sets required manual coding. Two of each set of manually coded meters were deliberately miscoded, and one from each set was properly coded. Subjects (n = 116) had finger stick blood glucose obtained at fasting, as well as at 1 and 2 hours after a fixed meal (Boost®; Novartis Medical Nutrition U.S., Basel, Switzerland). Deviations of meter blood glucose results from the reference method (YSI) were used to predict insulin dose errors and resultant blood glucose outcomes based on these deviations. Results Using insulin sensitivity data, it was determined that, given an actual blood glucose of 150–400 mg/dl, an error greater than +40 mg/dl would be required to calculate an insulin dose sufficient to produce a blood glucose of less than 70 mg/dl. Conversely, an error less than or equal to -70 mg/dl would be required to derive an insulin dose insufficient to correct an elevated blood glucose to less than 180 mg/dl. For miscoded meters, the estimated probability to produce a blood glucose reduction to less than or equal to 70 mg/dl was 10.40%. The corresponding probabilities for autocoded and correctly coded manual meters were 2.52% (p < 0.0001) and 1.46% (p < 0.0001), respectively. Furthermore, the errors from miscoded meters were large enough to produce a calculated blood glucose outcome less than or equal to 50 mg/dl in 42 of 833 instances. Autocoded meters produced zero (0) outcomes less than or equal to 50 mg/dl out of 279 instances, and correctly coded manual meters produced 1 of 416. Conclusions Improperly coded blood glucose meters present the potential for insulin dose errors and resultant clinically significant hypoglycemia or hyperglycemia. Patients should be instructed and periodically reinstructed in the proper use of blood glucose meters, particularly for meters that require coding. PMID:19885229

Using the Mean Shift Algorithm to Make Post Hoc Improvements to the Accuracy of Eye Tracking Data Based on Probable Fixation Locations

DTIC Science & Technology

2010-08-01

astigmatism and other sources, and stay constant from time to time (LC Technologies, 2000). Systematic errors can sometimes reach many degrees of visual angle...Taking the average of all disparities would mean treating each as equally important regardless of whether they are from correct or incorrect mappings. In...likely stop somewhere near the centroid because the large hM basically treats every point equally (or nearly equally if using the multivariate

Using SEM to Analyze Complex Survey Data: A Comparison between Design-Based Single-Level and Model-Based Multilevel Approaches

ERIC Educational Resources Information Center

Wu, Jiun-Yu; Kwok, Oi-man

2012-01-01

Both ad-hoc robust sandwich standard error estimators (design-based approach) and multilevel analysis (model-based approach) are commonly used for analyzing complex survey data with nonindependent observations. Although these 2 approaches perform equally well on analyzing complex survey data with equal between- and within-level model structures…

Pairwise comparisons and visual perceptions of equal area polygons.

PubMed

Adamic, P; Babiy, V; Janicki, R; Kakiashvili, T; Koczkodaj, W W; Tadeusiewicz, R

2009-02-01

The number of studies related to visual perception has been plentiful in recent years. Participants rated the areas of five randomly generated shapes of equal area, using a reference unit area that was displayed together with the shapes. Respondents were 179 university students from Canada and Poland. The average error estimated by respondents using the unit square was 25.75%. The error was substantially decreased to 5.51% when the shapes were compared to one another in pairs. This gain of 20.24% for this two-dimensional experiment was substantially better than the 11.78% gain reported in the previous one-dimensional experiments. This is the first statistically sound two-dimensional experiment demonstrating that pairwise comparisons improve accuracy.

Purification of Logic-Qubit Entanglement.

PubMed

Zhou, Lan; Sheng, Yu-Bo

2016-07-05

Recently, the logic-qubit entanglement shows its potential application in future quantum communication and quantum network. However, the entanglement will suffer from the noise and decoherence. In this paper, we will investigate the first entanglement purification protocol for logic-qubit entanglement. We show that both the bit-flip error and phase-flip error in logic-qubit entanglement can be well purified. Moreover, the bit-flip error in physical-qubit entanglement can be completely corrected. The phase-flip in physical-qubit entanglement error equals to the bit-flip error in logic-qubit entanglement, which can also be purified. This entanglement purification protocol may provide some potential applications in future quantum communication and quantum network.

Initial Steps Toward Next-Generation, Waveform-Based, Three-Dimensional Models and Metrics to Improve Nuclear Explosion Monitoring in the Middle East

DTIC Science & Technology

2008-09-30

propagation effects by splitting apart the longer period surface waves from the shorter period, depth-sensitive Pnl waves. Problematic, or high-error... Pnl waves. Problematic, or high-error, stations and paths were further analyzed to identify systematic errors with unknown sensor responses and...frequency Pnl components and slower, longer period surface waves. All cut windows are fit simultaneously, allowing equal weighting of phases that may be

High-throughput, fully-automated volumetry for prediction of MMSE and CDR decline in mild cognitive impairment

PubMed Central

Kovacevic, Sanja; Rafii, Michael S.; Brewer, James B.

2008-01-01

Medial temporal lobe (MTL) atrophy is associated with increased risk for conversion to Alzheimer's disease (AD), but manual tracing techniques and even semi-automated techniques for volumetric assessment are not practical in the clinical setting. In addition, most studies that examined MTL atrophy in AD have focused only on the hippocampus. It is unknown the extent to which volumes of amygdala and temporal horn of the lateral ventricle predict subsequent clinical decline. This study examined whether measures of hippocampus, amygdala, and temporal horn volume predict clinical decline over the following 6-month period in patients with mild cognitive impairment (MCI). Fully-automated volume measurements were performed in 269 MCI patients. Baseline volumes of the hippocampus, amygdala, and temporal horn were evaluated as predictors of change in Mini-mental State Exam (MMSE) and Clinical Dementia Rating Sum of Boxes (CDR SB) over a 6-month interval. Fully-automated measurements of baseline hippocampus and amygdala volumes correlated with baseline delayed recall scores. Patients with smaller baseline volumes of the hippocampus and amygdala or larger baseline volumes of the temporal horn had more rapid subsequent clinical decline on MMSE and CDR SB. Fully-automated and rapid measurement of segmental MTL volumes may help clinicians predict clinical decline in MCI patients. PMID:19474571

Response to rivastigmine transdermal patch or memantine plus rivastigmine patch is affected by apolipoprotein E genotype in Alzheimer patients.

PubMed

Han, Hyun Jeong; Kim, Byeong C; Lee, Jun-Young; Ryu, Seung-Ho; Na, Hae Ri; Yoon, Soo Jin; Park, Hyun Young; Shin, Joon Hyun; Cho, Soo-Jin; Yi, Hyon-Ah; Choi, Mun Seong; Heo, Jae-Hyeok; Park, Kyung Won; Kim, Kwang K; Choi, Seong Hye

2012-01-01

The apolipoprotein E (APOE) genotype in response to pharmacological treatments in patients with Alzheimer's disease (AD) remains a matter of controversy. This analysis investigated the effect of the APOE genotype on the clinical response to rivastigmine transdermal patch monotherapy or memantine plus rivastigmine patch in patients with mild to moderate AD. Two hundred and six (n = 206) patients with probable AD and Mini-Mental State Examination (MMSE) scores of 10-20 were randomized to rivastigmine patch monotherapy or memantine plus rivastigmine patch for 24 weeks. Of the 206 patients with probable AD, 146 patients who consented to genetic testing for APOE were included and assessed for this subgroup study. There were no significant differences on MMSE, NPI, ADAS-cog, ADCS-ADL, CDR-SB, NPI and FAB between rivastigmine patch monotherapy and memantine plus rivastigmine patch according to the APOE genotype. However, patients with moderately severe AD (MMSE ≤15) who were APOE ε4 carriers showed higher responder rates on ADCS-ADL with memantine plus rivastigmine patch compared to rivastigmine patch monotherapy. Moderately severe AD patients with the APOE ε4 allele may respond more favorably to memantine plus rivastigmine patch than ε4 noncarriers. Copyright © 2012 S. Karger AG, Basel.

Investigation of Genetic Variants Associated with Alzheimer Disease in Parkinson Disease Cognition.

PubMed

Barrett, Matthew J; Koeppel, Alexander F; Flanigan, Joseph L; Turner, Stephen D; Worrall, Bradford B

2016-01-01

Meta-analysis of genome-wide association studies have implicated multiple single nucleotide polymorphisms (SNPs) and associated genes with Alzheimer disease. The role of these SNPs in cognitive impairment in Parkinson disease (PD) remains incompletely evaluated. The objective of this study was to test alleles associated with risk of Alzheimer disease for association with cognitive impairment in Parkinson disease (PD). Two datasets with PD subjects accessed through the NIH database of Genotypes and Phenotypes contained both single nucleotide polymorphism (SNP) arrays and mini-mental state exam (MMSE) scores. Genetic data underwent rigorous quality control and we selected SNPs for genes associated with AD other than APOE. We constructed logistic regression and ordinal regression models, adjusted for sex, age at MMSE, and duration of PD, to assess the association between selected SNPs and MMSE score. In one dataset, PICALM rs3851179 was associated with cognitive impairment (MMSE <  24) in PD subjects > 70 years old (OR = 2.3; adjusted p-value = 0.017; n = 250) but not in PD subjects ≤ 70 years old. Our finding suggests that PICALM rs3851179 could contribute to cognitive impairment in older patients with PD. It is important that future studies consider the interaction of age and genetic risk factors in the development of cognitive impairment in PD.

The effect of shunt surgery on neuropsychological performance in normal pressure hydrocephalus: a systematic review and meta-analysis.

PubMed

Peterson, Katie A; Savulich, George; Jackson, Dan; Killikelly, Clare; Pickard, John D; Sahakian, Barbara J

2016-08-01

We conducted a systematic review of the literature and used meta-analytic techniques to evaluate the impact of shunt surgery on neuropsychological performance in patients with normal pressure hydrocephalus (NPH). Twenty-three studies with 1059 patients were identified for review using PubMed, Web of Science, Google scholar and manual searching. Inclusion criteria were prospective, within-subject investigations of cognitive outcome using neuropsychological assessment before and after shunt surgery in patients with NPH. There were statistically significant effects of shunt surgery on cognition (Mini-Mental State Examination; MMSE), learning and memory (Rey Auditory Verbal Learning Test; RAVLT, total and delayed subtests), executive function (backwards digit span, phonemic verbal fluency, trail making test B) and psychomotor speed (trail making test A) all in the direction of improvement following shunt surgery, but with considerable heterogeneity across all measures. A more detailed examination of the data suggested robust evidence for improved MMSE, RAVLT total, RAVLT delayed, phonemic verbal fluency and trail making test A only. Meta-regressions revealed no statistically significant effect of age, sex or follow-up interval on improvement in the MMSE. Our results suggest that shunt surgery is most sensitive for improving global cognition, learning and memory and psychomotor speed in patients with NPH.

Chocolate Consumption is Associated with a Lower Risk of Cognitive Decline.

PubMed

Moreira, Afonso; Diógenes, Maria José; de Mendonça, Alexandre; Lunet, Nuno; Barros, Henrique

2016-05-06

Cocoa-related products like chocolate have taken an important place in our food habits and culture. In this work, we aim to examine the relationship between chocolate consumption and cognitive decline in an elderly cognitively healthy population. In the present longitudinal prospective study, a cohort of 531 participants aged 65 and over with normal Mini-Mental State Examination (MMSE; median 28) was selected. The median follow-up was 48 months. Dietary habits were evaluated at baseline. The MMSE was used to assess global cognitive function at baseline and at follow-up. Cognitive decline was defined by a decrease ≥ 2 points in the MMSE score between evaluations. Relative risk (RR) and 95% confidence interval (95% CI) estimates were adjusted for age, education, smoking, alcohol drinking, body mass index, hypertension, and diabetes. Chocolate intake was associated with a lower risk of cognitive decline (RR = 0.59, 95% CI 0.38-0.92). This protective effect was observed only among subjects with an average daily consumption of caffeine lower than 75 mg (69% of the participants; RR = 0.50, 95% CI 0.31-0.82). To our knowledge, this is the first prospective cohort study to show an inverse association between regular long-term chocolate consumption and cognitive decline in humans.

Medical Patients’ Treatment Decision Making Capacity: A Report from a General Hospital in Greece

PubMed Central

Bilanakis, Nikolaos; Vratsista, Aikaterini; Athanasiou, Eleni; Niakas, Dimitris; Peritogiannis, Vaios

2014-01-01

This study aimed to assess the decision-making capacity for treatment of patients hospitalized in an internal medicine ward of a General Hospital in Greece, and to examine the views of treating physicians regarding patients’ capacity. All consecutive admissions to an internal medicine ward within a month were evaluated. A total of 134 patients were approached and 78 patients were interviewed with the MacArthur Competence Assessment Tool for Treatment (MacCAT-T) and the Mini Mental State Examination (MMSE) questionnaire. Sixty-eight out of 134 patients (50.7%) were incompetent to decide upon their treatment. The majority of them (n=56, 41.8%) were obviously incapable because they were unconscious, or had such marked impairment that they could not give their own names, and the rest (n=12, 8.9%) were rated as incompetent according to their performance in the MacCAT-T. Neurological disorders, old age and altered cognitive function according to MMSE were negatively correlated with decision making capacity. Physicians sometimes failed to recognize patients’ incapacity. Rates of decision-making incapacity for treatment in medical inpatients are high, and incapacity may go unrecognized by treating physicians. Combined patient evaluation with the use of the MacCAT-T and MMSE, could be useful for the determination of incapable patients. PMID:25505489

Resistance Training Exercise Program for Intervention to Enhance Gait Function in Elderly Chronically Ill Patients: Multivariate Multiscale Entropy for Center of Pressure Signal Analysis

PubMed Central

Jiang, Bernard C.

2014-01-01

Falls are unpredictable accidents, and the resulting injuries can be serious in the elderly, particularly those with chronic diseases. Regular exercise is recommended to prevent and treat hypertension and other chronic diseases by reducing clinical blood pressure. The “complexity index” (CI), based on multiscale entropy (MSE) algorithm, has been applied in recent studies to show a person's adaptability to intrinsic and external perturbations and widely used measure of postural sway or stability. The multivariate multiscale entropy (MMSE) was advanced algorithm used to calculate the complexity index (CI) values of the center of pressure (COP) data. In this study, we applied the MSE & MMSE to analyze gait function of 24 elderly, chronically ill patients (44% female; 56% male; mean age, 67.56 ± 10.70 years) with either cardiovascular disease, diabetes mellitus, or osteoporosis. After a 12-week training program, postural stability measurements showed significant improvements. Our results showed beneficial effects of resistance training, which can be used to improve postural stability in the elderly and indicated that MMSE algorithms to calculate CI of the COP data were superior to the multiscale entropy (MSE) algorithm to identify the sense of balance in the elderly. PMID:25295070

Subclinical hypothyroidism and cognitive dysfunction in the elderly.

PubMed

Resta, F; Triggiani, V; Barile, G; Benigno, M; Suppressa, P; Giagulli, V A; Guastamacchia, E; Sabbà, C

2012-09-01

While overt hypothyroidism is associated with reversible dementia in the elderly, the relationship of subclinical hypothyroidism with cognition remains a controversial issue. Our aim was to investigate the correlation between subclinical hypothyroidism and cognition in the elderly, with particular reference to long term memory and selective attention. We selected 337 outpatients (177 men and 160 women), mean age 74.3 years, excluding the subjects with thyroid dysfunction and those treated with drugs influencing thyroid function. The score of Mini Mental State Examination (MMSE) was significantly lower in the group of patients with subclinical hypothyroidism than in euthyroid subjects (p<0.03). It was observed that patients with subclinical hypothyroidism had a probability about 2 times greater (RR = 2.028, p<0.05) of developing cognitive impairment. Prose Memory Test (PMT) score resulted significantly lower in subjects with subclinical hypothyroidism (p<0.04). Considering the Matrix Test (MT) score, the performance was slightly reduced in subclinical hypothyroidism (NS). Furthermore, TSH was negatively correlated with MMSE (p<0.04), PMT (p<0.05) and MT score (NS). No correlation was found between FT4 and FT3 and MMSE, PMT and MT score. In the elderly, subclinical hypothyroidism is associated with cognitive impairment, and its impact on specific aspects of cognition (long term memory and selective attention) is less evident.

Modeling the Association between 43 Different Clinical and Pathological Variables and the Severity of Cognitive Impairment in a Large Autopsy Cohort of Elderly Persons

PubMed Central

Nelson, Peter T.; Abner, Erin L.; Schmitt, Frederick A.; Kryscio, Richard J.; Jicha, Gregory A.; Smith, Charles D.; Davis, Daron G.; Poduska, John W.; Patel, Ela; Mendiondo, Marta S.; Markesbery, William R.

2009-01-01

We evaluated the association between mini-mental status examination (MMSE) scores proximal to death and the values of 43 different clinical and pathological parameters. Studies were performed using data from 334 elderly, longitudinally evaluated research subjects who had undergone autopsy and satisfied inclusion criteria from an initial study group of 501. Interindividual variance in MMSE scores was used as a surrogate for the severity of cognitive impairment linked to aging (CILA). A statistical linear regression-based model provided a framework for assessing the parameters with significant, direct impact on CILA severity. Strong association between CILA and Alzheimer’s disease (AD) pathology, especially isocortical neurofibrillary tangles, was evident. The pattern of association between AD lesion densities with cognitive impairment severity was biologically informative, with neuritic plaques having more impact in relatively high-functioning individuals. Abundant isocortical Lewy bodies tended to be an additive pathology correlating with final MMSE scores approximately 10 points lower. In a subset of cases we found evidence for association between TDP-43-related pathology and CILA severity, independent of AD or hippocampal sclerosis. There was no support for independent association between CILA severity and most evaluated indices including diffuse plaques, argyrophilic grains, heart disease, education level, apolipoprotein E alleles or diabetes. PMID:19021630

Cognitive decline and survival in Alzheimer's disease according to education level.

PubMed

Bruandet, A; Richard, F; Bombois, S; Maurage, C A; Masse, I; Amouyel, P; Pasquier, F

2008-01-01

We tested the hypothesis that a higher education level is associated with faster cognitive decline and lower survival in a cohort of 670 Alzheimer's disease patients, followed for 3.5 years at the Lille-Bailleul memory centre. The patients were categorized in 3 groups according to educational levels: low (12 years). Cognitive function was measured with the Mini Mental State Examination (MMSE) and the Mattis Dementia Rating Scale (DRS). Survival was analyzed with a Cox model. Analyses were adjusted for age, sex, cholinesterase inhibitor treatment, diabetes, hypertension, visible vascular lesions on MRI, baseline DRS and MMSE. The adjusted mixed random model showed that MMSE declined faster for patients with high and intermediate educational levels compared with those with a low educational level (p < 0.0001). The mean annually adjusted DRS decline was highest for the groups with the most education (p = 0.05). The mortality risk was not higher in the better-educated groups (high vs. low: RR = 0.84; 95% CI = 0.35-1.99, intermediate vs. low: RR = 0.82; 95% CI = 0.41-1.63). In our cohort, highly educated patients had a faster cognitive decline than less educated patients but similar mortality rates. Our findings support the cognitive reserve hypothesis. (c) 2007 S. Karger AG, Basel.

Factors Associated with Performance-based Physical Function of Older Veterans of the PLAAF: A Pilot Study

PubMed Central

Chen, Da-Wei; Jin, Yan-Bin; Liu, Wei; Du, Wen-Jin; Li, Hua-Jun; Chen, Jin-Wen; Xu, Wei

2014-01-01

[Purpose] This study investigated the factors associated with performance-based physical function of older veterans of the People’s Liberation Army Air Force of China (PLAAF). [Subjects and Methods] A cross-sectional survey of 146 older veterans of the PLAAF was carried out. Their physical function was measured using the Chinese Mini-Physical Performance Testing (CM-PPT). The demographics and health status (including physical measures, blood chemical tests, chronic diseases, and number of morbidities) were collected from health examination reports and computer records of case history. Cognition was measured using the Mini-Mental Status Examination (MMSE). [Results] In multiple linear regressions, age, MMSE, Parkinsonism, and chronic obstructive pulmonary disease were independently associated with CM-PPT, while previous stroke and albumin level reached borderline statistical significance. The association between the number of morbidities and CM-PPT was significant after adjustment for MMSE and demographics. The CM-PPT of low (0 or 1), medium (2 to 4) and high count (5 or more) morbidities were 11.3±3.9, 10.2±4.1, 6.1±3.8 respectively, and the difference among these three groups was significant. [Conclusion] Some modified conditions and the number of chronic diseases might be associated with the physical function of older veterans of the PLAAF. PMID:24648625

Optical Coherence Tomography Noise Reduction Using Anisotropic Local Bivariate Gaussian Mixture Prior in 3D Complex Wavelet Domain.

PubMed

Rabbani, Hossein; Sonka, Milan; Abramoff, Michael D

2013-01-01

In this paper, MMSE estimator is employed for noise-free 3D OCT data recovery in 3D complex wavelet domain. Since the proposed distribution for noise-free data plays a key role in the performance of MMSE estimator, a priori distribution for the pdf of noise-free 3D complex wavelet coefficients is proposed which is able to model the main statistical properties of wavelets. We model the coefficients with a mixture of two bivariate Gaussian pdfs with local parameters which are able to capture the heavy-tailed property and inter- and intrascale dependencies of coefficients. In addition, based on the special structure of OCT images, we use an anisotropic windowing procedure for local parameters estimation that results in visual quality improvement. On this base, several OCT despeckling algorithms are obtained based on using Gaussian/two-sided Rayleigh noise distribution and homomorphic/nonhomomorphic model. In order to evaluate the performance of the proposed algorithm, we use 156 selected ROIs from 650 × 512 × 128 OCT dataset in the presence of wet AMD pathology. Our simulations show that the best MMSE estimator using local bivariate mixture prior is for the nonhomomorphic model in the presence of Gaussian noise which results in an improvement of 7.8 ± 1.7 in CNR.

On Two-Stage Multiple Comparison Procedures When There Are Unequal Sample Sizes in the First Stage.

ERIC Educational Resources Information Center

Wilcox, Rand R.

1984-01-01

Two stage multiple-comparison procedures give an exact solution to problems of power and Type I errors, but require equal sample sizes in the first stage. This paper suggests a method of evaluating the experimentwise Type I error probability when the first stage has unequal sample sizes. (Author/BW)

Predictors of Rapid Cognitive Decline in Patients with Mild-to-Moderate Alzheimer Disease: A Prospective Cohort Study with 12-Month Follow-Up Performed in Memory Clinics.

PubMed

Tchalla, Achille E; Clément, Jean-Pierre; Saulnier, Isabelle; Beaumatin, Betty; Lachal, Florent; Gayot, Caroline; Bosetti, Anaïs; Desormais, Iléana; Perrochon, Anaïck; Preux, Pierre-Marie; Couratier, Philippe; Dantoine, Thierry

2018-04-23

Alzheimer disease (AD) is particularly devastating, with no cure, no means of prevention, and no proven way to slow progression. AD is associated with the worsening of cognitive function attributable to a variety of factors of which little is known. Our main objective was to determine factors associated with rapid cognitive decline (RCD) in older AD patients. We conducted a 12-month, prospective, multi-centre cohort study. Community-living individuals aged ≥65 years with mild-to-moderate AD were included. RCD was defined as the loss of ≥3 points/year in the Mini-Mental State Examination (MMSE) score. Potential individual-level predictors were collected at baseline. A total of 521 individuals were included. The mean age was 80.8 ± 9.0 years and 66.0% were females. The average baseline MMSE score was 20.5 ± 4.5. The incidence of RCD was 40.9% (95% confidence interval [CI], 36.7-45.1). RCD was more common in patients with moderate (53.5%) than mild (22.3%) AD. The factors associated with RCD were: a parental history of dementia (odds ratio [OR], 2.32 [95% CI, 1.24-4.21], p = 0.011), psychotic symptoms (OR, 2.06 [95% CI, 1.22-3.48], p = 0.007), malnutrition (OR, 1.61 [95% CI, 1.06-2.63], p = 0.028), and the female gender (OR, 1.48 [95% CI, 1.03-2.15], p = 0.036). An MMSE score < 20 at treatment onset was also associated with RCD (p < 0.001). The factors associated with RCD were an MMSE score < 20 at treatment onset, female gender, psychotic symptoms, malnutrition, and a family history of dementia. These results may be directly relevant to patients, their families, and their physicians, enabling early anticipation of difficult clinical trajectories and poor functional outcomes. © 2018 S. Karger AG, Basel.

Predictors of cognitive impairment in an early stage Parkinson's disease cohort.

PubMed

Hu, Michele T M; Szewczyk-Królikowski, Konrad; Tomlinson, Paul; Nithi, Kannan; Rolinski, Michal; Murray, Clara; Talbot, Kevin; Ebmeier, Klaus P; Mackay, Clare E; Ben-Shlomo, Yoav

2014-03-01

The impact of Parkinson's disease (PD) dementia is substantial and has major functional and socioeconomic consequences. Early prediction of future cognitive impairment would help target future interventions. The Montreal Cognitive Assessment (MoCA), the Mini-Mental State Examination (MMSE), and fluency tests were administered to 486 patients with PD within 3.5 years of diagnosis, and the results were compared with those from 141 controls correcting for age, sex, and educational years. Eighteen-month longitudinal assessments were performed in 155 patients with PD. The proportion of patients classified with normal cognition, mild cognitive impairment (MCI), and dementia varied considerably, depending on the MoCA and MMSE thresholds used. With the MoCA total score at screening threshold, 47.7%, 40.5%, and 11.7% of patients with PD were classified with normal cognition, MCI, and dementia, respectively; by comparison, 78.7% and 21.3% of controls had normal cognition and MCI, respectively. Cognitive impairment was predicted by lower education, increased age, male sex, and quantitative motor and non-motor (smell, depression, and anxiety) measures. Longitudinal data from 155 patients with PD over 18 months showed significant reductions in MoCA scores, but not in MMSE scores, with 21.3% of patients moving from normal cognition to MCI and 4.5% moving from MCI to dementia, although 13.5% moved from MCI to normal; however, none of the patients with dementia changed their classification. The MoCA may be more sensitive than the MMSE in detecting early baseline and longitudinal cognitive impairment in PD, because it identified 25.8% of those who experienced significant cognitive decline over 18 months. Cognitive decline was associated with worse motor and non-motor features, suggesting that this reflects a faster progressive phenotype. © 2014 The Authors. International Parkinson and Movement Disorder Society published by Wiley Periodicals, Inc.

First Spanish version of the Memorial Delirium Assessment Scale: psychometric properties, responsiveness, and factor loadings.

PubMed

Noguera, Antonio; Carvajal, Ana; Alonso-Babarro, Alberto; Chisholm, Gary; Bruera, Eduardo; Centeno, Carlos

2014-01-01

The Memorial Delirium Assessment Scale (MDAS) is a reliable and validated instrument with which to assess delirium. However, MDAS responsiveness has only been investigated in an indirect way. Also, neurobehavioral and global cognitive factors seem to be the MDAS main factor loads. The primary objective of this study was to evaluate MDAS responsiveness and analyze individual factors on this scale. The secondary objective was to confirm concurrent validity and reliability of the Spanish version of the MDAS. The translation-back translation method was used to obtain the Spanish version of the MDAS. Delirium diagnosis was determined by the clinical Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria and with the Confusion Assessment Method. Responsiveness and factor loadings were determined with the Delirium Rating Scale-Revised-98, the Mini-Mental State Examination (MMSE), and the MDAS at baseline (0 hours) and at 72 hours. Variation in the scores of the Delirium Rating Scale-Revised-98 shows a correlation of r = 0.93, with variation in MDAS scores at P < 0.001. Variation in MMSE scores shows a correlation of r = -0.84, with variation in MDAS scores at P = 0.015. Factor I, neurobehavioral (reduced awareness, reduced attention, perceptual disturbance, delusions, altered psychomotor activity, and sleep-wake cycle disturbance), correlated moderately with the MMSE at -0.56. Factor II, global cognitive (disorientation, short-term memory impairment, impaired digit span, and disorganized thinking), correlated strongly with the MMSE at -0.81. Factor II was significantly more reliable than Factor I, rho = 0.7, P = 0.01. The high responsiveness confirms the value of the MDAS for ongoing delirium assessment. Two differentiated factor loadings point to a potential future need for MDAS subscales. Copyright © 2014 U.S. Cancer Pain Relief Committee. All rights reserved.

ApoE and SNAP-25 Polymorphisms Predict the Outcome of Multidimensional Stimulation Therapy Rehabilitation in Alzheimer's Disease.

PubMed

Guerini, Franca Rosa; Farina, Elisabetta; Costa, Andrea Saul; Baglio, Francesca; Saibene, Francesca Lea; Margaritella, Nicolò; Calabrese, Elena; Zanzottera, Milena; Bolognesi, Elisabetta; Nemni, Raffaello; Clerici, Mario

2016-10-01

Alzheimer's disease (AD) is a highly prevalent neurodegenerative disorder. Rate of decline and functional restoration in AD greatly depend on the capacity for neural plasticity within residual neural tissues; this is at least partially influenced by polymorphisms in genes that determine neural plasticity, including Apolipoprotein E4 (ApoE4) and synaptosomal-associated protein of 25 kDa (SNAP-25). We investigated whether correlations could be detected between polymorphisms of ApoE4 and SNAP-25 and the outcome of a multidimensional rehabilitative approach, based on cognitive stimulation, behavioral, and functional therapy (multidimensional stimulation therapy [MST]). Fifty-eight individuals with mild-to-moderate AD underwent MST for 10 weeks. Neuro-psychological functional and behavioral evaluations were performed blindly by a neuropsychologist at baseline and after 10 weeks of therapy using Mini-Mental State Examination (MMSE), Functional Living Skill Assessment (FLSA), and Neuropsychiatric Inventory (NPI) scales. Molecular genotyping of ApoE4 and SNAP-25 rs363050, rs363039, rs363043 was performed. Results were correlated with ΔMMSE, ΔNPI and ΔFLSA scores by multinomial logistic regression analysis. Polymorphisms in both genes correlated with the outcome of MST for MMSE and NPI scores. Thus, higher overall MMSE scores after rehabilitation were detected in ApoE4 negative compared to ApoE4 positive patients, whereas the SNAP-25 rs363050(G) and rs363039(A) alleles correlated with significant improvements in behavioural parameters. Polymorphisms in genes known to modulate neural plasticity might predict the outcome of a multistructured rehabilitation protocol in patients with AD. These data, although needing confirmation on larger case studies, could help optimizing the clinical management of individuals with AD, for example defining a more intensive treatment in those subjects with a lower likelihood of success. © The Author(s) 2016.

Posterior Teeth Occlusion Associated with Cognitive Function in Nursing Home Older Residents: A Cross-Sectional Observational Study

PubMed Central

Takeuchi, Kenji; Izumi, Maya; Furuta, Michiko; Takeshita, Toru; Shibata, Yukie; Kageyama, Shinya; Ganaha, Seijun; Yamashita, Yoshihisa

2015-01-01

Early detection and subsequent reduction of modifiable risk factors for cognitive decline is important for extending healthy life expectancy in the currently aging society. Although a recent increase in studies on the state or number of the teeth and cognitive function, few studies have focused on the association between posterior teeth occlusion necessary to maintain chewing function and cognitive function among older adults. This study examined the association between posterior teeth occlusion and cognitive function in nursing home older residents. In this cross-sectional study, 279 residents aged ≥60 years from eight nursing homes in Aso City, Japan participated in cognitive function and dental status assessments and completed a comprehensive questionnaire survey in 2014. Cognitive function was measured using a Mini-Mental State Examination (MMSE). Posterior teeth occlusion was assessed using a total number of functional tooth units (total-FTUs), depending on the number and location of the remaining natural and artificial teeth on implant-supported, fixed, and removable prostheses. Linear regression models were used to assess univariate and multivariate associations between total-FTUs and MMSE scores. Models were sequentially adjusted for demographic characteristics, number of natural teeth, socioeconomic status, health behaviors, comorbidities, physical function, and nutritional status. Among the 200 residents included in our analysis, mean MMSE scores and total-FTUs were 11.0 ± 8.6 and 9.3 ± 4.6, respectively. Higher total-FTUs were significantly associated with higher MMSE scores after adjustment for demographics and teeth number (B = 0.48, 95% confidence interval [CI] = 0.22–0.74). The association remained significant even after adjustment for all covariates (B = 0.25, 95% CI = 0.01–0.49). The current findings demonstrated that loss of posterior teeth occlusion was independently associated with cognitive decline in nursing home older residents in Japan. Maintenance and restoration of posterior teeth occlusion may be a preventive factor against cognitive decline in aged populations. PMID:26512900

Is Social Network a Protective Factor for Cognitive Impairment in US Chinese Older Adults? Findings from the PINE Study.

PubMed

Li, Mengting; Dong, Xinqi

2018-01-01

Social network has been identified as a protective factor for cognitive impairment. However, the relationship between social network and global and subdomains of cognitive function remains unclear. This study aims to provide an analytic framework to examine quantity, composition, and quality of social network and investigate the association between social network, global cognition, and cognitive domains among US Chinese older adults. Data were derived from the Population Study of Chinese Elderly (PINE), a community-engaged, population-based epidemiological study of US Chinese older adults aged 60 and above in the greater Chicago area, with a sample size of 3,157. Social network was assessed by network size, volume of contact, proportion kin, proportion female, proportion co-resident, and emotional closeness. Cognitive function was evaluated by global cognition, episodic memory, executive function, working memory, and Chinese Mini-Mental State Examination (C-MMSE). Linear regression and quantile regression were performed. Every 1-point increase in network size (b = 0.048, p < 0.001) and volume of contact (b = 0.049, p < 0.01) and every 1-point decrease in proportion kin (b = -0.240, p < 0.01) and proportion co-resident (b = -0.099, p < 0.05) were associated with higher level of global cognition. Similar trends were observed in specific cognitive domains, including episodic memory, working memory, executive function, and C-MMSE. However, emotional closeness was only significantly associated with C-MMSE (b = 0.076, p < 0.01). Social network has differential effects on female versus male older adults. This study found that social network dimensions have different relationships with global and domains of cognitive function. Quantitative and structural aspects of social network were essential to maintain an optimal level of cognitive function. Qualitative aspects of social network were protective factors for C-MMSE. It is necessary for public health practitioners to consider interventions that enhance different aspects of older adults' social network. © 2017 S. Karger AG, Basel.

Evaluating driving performance of outpatients with Alzheimer disease.

PubMed

Cox, D J; Quillian, W C; Thorndike, F P; Kovatchev, B P; Hanna, G

1998-01-01

Alzheimer disease (AD) is a progressive disease, with multiple physiologic, psychologic, and social implications. A critical issue in its management is when to recommend restrictions on autonomous functioning, such as driving an automobile. This study evaluates driving performance of patients with AD and its relation to patient scores on the Mini-Mental State Exam (MMSE). This study compared 29 outpatients with probable AD with 21 age-matched control participants on an interactive driving simulator to determine how the two groups differed and how such differences related to mental status. Patients with AD (1) were less likely to comprehend and operate the simulator cognitively, (2) drove off the road more often, (3) spent more time driving considerably slower than the posted speed limit, (4) spent less time driving faster than the speed limit, (5) applied less brake pressure in stop zones, (6) spent more time negotiating left turns, and (7) drove more poorly overall. There were no observed differences between AD patients and the control group in terms of crossing the midline and driving speed variability. Among the AD patients, those who could not drive the simulator because of confusion and disorientation (n = 10) had lower MMSE scores and drove fewer miles annually. Those AD patients who had stopped driving also scored lower on their MMSE but did not perform more poorly on the driving simulator. Factor analysis revealed five driving factors associated with AD, explaining 93 percent of the variance. These five factors correctly classified 27 (85 percent) of 32 AD patients compared with the control group. Of the 15 percent who were improperly classified, there were three false positives (control participants misclassified as AD patients) and two false negatives (AD patients misclassified as control participants). The computed total driving score correlated significantly with MMSE scores (r = -.403, P = 0.011). Driving simulators can provide an objective means of assessing driving safety.

Prevalence of depression in stroke patients with vascular dementia in universiti kebangsaan malaysia medical center.

PubMed

Khoo, K F; Tan, H J; R, Rosdinom; Raymond, A A; M I, Norlinah; A, Shamsul; W Y, Nafisah

2013-04-01

Depression among patients with vascular dementia is frequently overlooked and potentially causes significant morbidity. There is limited data in Malaysia on the subject and this study was conducted to determine the prevalence of depression in vascular dementia (VaD) in UKMMC. This was a cross-sectional study involving diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM IV) criteria and who had a mini mental state examination (MMSE) score of less than 26. All patients were interviewed, examined clinically and their previous brain computer tomography (CT) were reviewed. The prevalence of depression was determined using the Cornell scale of depression. A total of 76 patients were recruited with a mean age of 70.5 ± 9.5 years. The median duration of illness was 2.0 (1.0-4.8) years. The prevalence of depression in the study population was 31.6%. The patients with depression had a significant older mean age (74.5±8.7 years old) compared to those without depression (68.6±9.4 years old). Patients with large artery stroke of less than 3 years had significant higher frequency of depression (53.6%) compared to patients with small artery stroke (23.8%) and patients with right sided large artery stroke had significantly higher frequency of depression compared to left (70% vs. 44.4%). Median MMSE score (17.0) for depressed patients was significantly lower compared with median MMSE score (22.5) for non depressed patients. Median Barthel Index (30.0) for depressed patients was significantly lower compared with median Barthel score for non depressed patients. Depression was prevalent among post stroke patients with VaD in UKMMC particularly for patients with older age, large artery stroke, right sided large artery stroke, low MMSE score and low Barthel Index. Early recognition of high risk patients is important in the holistic management of patients to prevent significant morbidity arising from depression.

Excessive variability in systolic blood pressure that is self-measured at home exacerbates the progression of brain white matter lesions and cognitive impairment in the oldest old.

PubMed

Liu, Zhendong; Zhao, Yingxin; Zhang, Hua; Chai, Qiang; Cui, Yi; Diao, Yutao; Xiu, Jianchao; Sun, Xiaolin; Jiang, Guosheng

2016-04-01

To investigate the effects of variability in self-measured systolic blood pressure at home on the progression of cognitive impairment and white matter lesions in the oldest old. Between April 2009 and October 2009, 248 oldest old aged 80 years or older were eligibly enrolled from geriatric practices and community-dwelling areas of Shandong, China. Self-measured blood pressure at home (HBP) was measured for 7 consecutive days at the baseline, and the Mini-Mental State Examination (MMSE) score and brain white matter hyperintensities (WMH) were assessed at the baseline and during the final follow-up visit. Variability in systolic HBP was evaluated using coefficient of variation (CV) in serial daily systolic HBP measurements of the last 6 consecutive days. After an average of 2.3 years of follow-up visits, 232 oldest old were included in and 16 were excluded from the analysis. The MMSE score declined -4.76 (interquartile ranges: -10.71, -0.83) %, the periventricular WMH, deep WMH, total WMH and WMH fraction increased 16.46 (s.d.: 6.72)%, 10.05 (s.d.: 6.40)%, 14.69 (s.d.: 6.07)% and 15.95 (s.d.: 6.32)%, respectively, in the total oldest old. A declined percentage of the MMSE score and increased percentages of the periventricular WMH, deep WMH, total WMH and WMH fraction in the high group divided by tertile of the CV of the systolic HBP at baseline were greater than those in the low group (P<0.05). The significant differences were retained after adjusting for covariates, including the MMSE score, periventricular WMH, deep WMH and WMH fraction at the baseline (P<0.05). Excessive variability in self-measured systolic HBP exacerbates the progression of cognitive impairment and brain white matter lesions in the oldest old.

[Effect of aluminum exposure on cognitive function in electrolytic workers and its influential factors].

PubMed

Lu, Xiao-ting; Liang, Rui-feng; Jia, Zhi-jian; Wang, Hao; Song, Wen-fei; Li, Qiu-ying; Niu, Qiao

2013-02-01

To clarify the effect of aluminum exposure on the cognitive function in electrolytic workers and the prevalence of mild cognitive impairment (MCI) among them by prevalence survey, and to investigate its influential factors. Sixty-six retired workers from the electrolysis workshop of an electrolytic aluminum plant were selected as an aluminum exposure group, while 70 retired workers from a flour mill in the same region were selected as a control group. MCI patients were screened out by Mini-Mental State Examination (MMSE); the blood aluminum level was measured by inductively coupled plasma-mass spectrometry; multivariate statistical analysis was used to investigate the influential factors for MMSE scores and the correlation between blood aluminum level and MCI prevalence. The aluminum exposure group showed a significantly higher blood aluminum level than the control group (25.18 ± 2.65 µg/L vs 9.97 ± 2.83 µg/L, P < 0.01). The total MMSE score of the aluminum exposure group (26.13 ± 2.57) was significantly lower than that of the control group (27.89 ± 1.91) (P < 0.05), particularly the scores on time and place orientation, short-term memory, calculation ability, and language skill (P < 0.05). The detection rate of MCI was significantly higher in the aluminum exposure group (18.2%) than in the control group (5.7%) (P < 0.01). The main influential factors for MMSE scores were gender, age, education level, and blood aluminum level. The logistic regression analysis indicated that the MCI prevalence was significantly correlated with blood aluminum level in the study population (OR = 1.168, P < 0.01). Long-term exposure to aluminum can cause cognitive disorders in electrolytic workers and may be one of the risk factors for MCI. Advanced age, male, low education level, and high blood aluminum level may be high-risk factors for cognitive impairment.

Effect of concomitant use of memantine on mortality and efficacy outcomes of galantamine-treated patients with Alzheimer's disease: post-hoc analysis of a randomized placebo-controlled study.

PubMed

Hager, Klaus; Baseman, Alan S; Nye, Jeffrey S; Brashear, H Robert; Han, John; Sano, Mary; Davis, Bonnie; Richards, Henry M

2016-11-15

A large, prospective, 2-year, randomized study in patients with mild-to-moderate Alzheimer's disease or mixed dementia demonstrated reductions in mortality and cognitive/functional decline in galantamine-treated patients. A post-hoc analysis was conducted to study the effect of (the presence or absence of) concomitant memantine use on treatment outcome. Randomized patients (N = 2045) were divided into subgroups based on memantine use. Analyses included demographic and clinical characteristics (age, nursing home placement, Mini-Mental State Examination (MMSE) and Disability Assessment for Dementia (DAD) scores) and mortality endpoints. Overall, 496 (24.3 %) patients were memantine users and were older (mean (SD), 74.0 (8.76) vs 72.8 (8.76), p = 0.008), with lower MMSE scores (18.2 (4.16) vs 19.2 (4.02), p < 0.0001) and DAD scores (58.0 (23.49) vs 62.5 (20.52), p < 0.0001) than nonusers. Mortality rates (per 100 patient-years) in memantine nonusers (n = 1549) were lower for galantamine (1.39) vs placebo-treated patients (4.15). In memantine users, mortality rates were similar for placebo-treated (4.49) and galantamine-treated patients (5.57). In memantine nonusers at 24 months, the decline in MMSE scores (effect size (95 % CI) 0.25 (0.14; 0.36)) and DAD scores (0.17 (0.06; 0.28)) from baseline was lower in galantamine patients vs placebo patients. The absence of these benefits in memantine users could not be explained by baseline age, MMSE, or DAD scores. This post-hoc analysis shows that the beneficial effects of galantamine at 2 years post treatment were not observed in patients who had been placed on background memantine. The reasons for memantine treatment and the possibility of interaction between memantine and galantamine merit further investigation. ClinicalTrials.gov NCT00679627 . Registered 15 May 2008.

Experiential Teaching Increases Medication Calculation Accuracy Among Baccalaureate Nursing Students.

PubMed

Hurley, Teresa V

Safe medication administration is an international goal. Calculation errors cause patient harm despite education. The research purpose was to evaluate the effectiveness of an experiential teaching strategy to reduce errors in a sample of 78 baccalaureate nursing students at a Northeastern college. A pretest-posttest design with random assignment into equal-sized groups was used. The experiential strategy was more effective than the traditional method (t = -0.312, df = 37, p = .004, 95% CI) with a reduction in calculation errors. Evaluations of error type and teaching strategies are indicated to facilitate course and program changes.

The calculation of average error probability in a digital fibre optical communication system

NASA Astrophysics Data System (ADS)

Rugemalira, R. A. M.

1980-03-01

This paper deals with the problem of determining the average error probability in a digital fibre optical communication system, in the presence of message dependent inhomogeneous non-stationary shot noise, additive Gaussian noise and intersymbol interference. A zero-forcing equalization receiver filter is considered. Three techniques for error rate evaluation are compared. The Chernoff bound and the Gram-Charlier series expansion methods are compared to the characteristic function technique. The latter predicts a higher receiver sensitivity

4.5-Gb/s RGB-LED based WDM visible light communication system employing CAP modulation and RLS based adaptive equalization.

PubMed

Wang, Yiguang; Huang, Xingxing; Tao, Li; Shi, Jianyang; Chi, Nan

2015-05-18

Inter-symbol interference (ISI) is one of the key problems that seriously limit transmission data rate in high-speed VLC systems. To eliminate ISI and further improve the system performance, series of equalization schemes have been widely investigated. As an adaptive algorithm commonly used in wireless communication, RLS is also suitable for visible light communication due to its quick convergence and better performance. In this paper, for the first time we experimentally demonstrate a high-speed RGB-LED based WDM VLC system employing carrier-less amplitude and phase (CAP) modulation and recursive least square (RLS) based adaptive equalization. An aggregate data rate of 4.5Gb/s is successfully achieved over 1.5-m indoor free space transmission with the bit error rate (BER) below the 7% forward error correction (FEC) limit of 3.8x10(-3). To the best of our knowledge, this is the highest data rate ever achieved in RGB-LED based VLC systems.

Power optimization of digital baseband WCDMA receiver components on algorithmic and architectural level

NASA Astrophysics Data System (ADS)

Schämann, M.; Bücker, M.; Hessel, S.; Langmann, U.

2008-05-01

High data rates combined with high mobility represent a challenge for the design of cellular devices. Advanced algorithms are required which result in higher complexity, more chip area and increased power consumption. However, this contrasts to the limited power supply of mobile devices. This presentation discusses the application of an HSDPA receiver which has been optimized regarding power consumption with the focus on the algorithmic and architectural level. On algorithmic level the Rake combiner, Prefilter-Rake equalizer and MMSE equalizer are compared regarding their BER performance. Both equalizer approaches provide a significant increase of performance for high data rates compared to the Rake combiner which is commonly used for lower data rates. For both equalizer approaches several adaptive algorithms are available which differ in complexity and convergence properties. To identify the algorithm which achieves the required performance with the lowest power consumption the algorithms have been investigated using SystemC models regarding their performance and arithmetic complexity. Additionally, for the Prefilter Rake equalizer the power estimations of a modified Griffith (LMS) and a Levinson (RLS) algorithm have been compared with the tool ORINOCO supplied by ChipVision. The accuracy of this tool has been verified with a scalable architecture of the UMTS channel estimation described both in SystemC and VHDL targeting a 130 nm CMOS standard cell library. An architecture combining all three approaches combined with an adaptive control unit is presented. The control unit monitors the current condition of the propagation channel and adjusts parameters for the receiver like filter size and oversampling ratio to minimize the power consumption while maintaining the required performance. The optimization strategies result in a reduction of the number of arithmetic operations up to 70% for single components which leads to an estimated power reduction of up to 40% while the BER performance is not affected. This work utilizes SystemC and ORINOCO for the first estimation of power consumption in an early step of the design flow. Thereby algorithms can be compared in different operating modes including the effects of control units. Here an algorithm having higher peak complexity and power consumption but providing more flexibility showed less consumption for normal operating modes compared to the algorithm which is optimized for peak performance.

The effect of donepezil on increased regional cerebral blood flow in the posterior cingulate cortex of a patient with Parkinson's disease dementia.

PubMed

Imamura, Keiko; Wada-Isoe, Kenji; Kowa, Hisanori; Tanabe, Yoshio; Nakashima, Kenji

2008-01-01

It has been reported that the cholinesterase inhibitor, donepezil, improves cognitive decline in patients with Parkinson's disease dementia (PDD). However, this improvement was dominant for frontal lobe dysfunction, and the increase in the Mini-Mental State Examination (MMSE) score was minimal. We report a PDD patient with a decline of regional cerebral blood flow (rCBF) in the posterior cingulate cortex, precunei, and bilateral parietotemporal association cortex, as determined by single-photon emission computed tomography (SPECT) using the easy Z-scores imaging system (e-ZIS). Upon administration of donepezil, both the rCBF and MMSE score increased. The effectiveness of donepezil may vary based on the rCBF pattern in PDD.

Purification of Logic-Qubit Entanglement

PubMed Central

Zhou, Lan; Sheng, Yu-Bo

2016-01-01

Recently, the logic-qubit entanglement shows its potential application in future quantum communication and quantum network. However, the entanglement will suffer from the noise and decoherence. In this paper, we will investigate the first entanglement purification protocol for logic-qubit entanglement. We show that both the bit-flip error and phase-flip error in logic-qubit entanglement can be well purified. Moreover, the bit-flip error in physical-qubit entanglement can be completely corrected. The phase-flip in physical-qubit entanglement error equals to the bit-flip error in logic-qubit entanglement, which can also be purified. This entanglement purification protocol may provide some potential applications in future quantum communication and quantum network. PMID:27377165

Analytical investigation of adaptive control of radiated inlet noise from turbofan engines

NASA Technical Reports Server (NTRS)

Risi, John D.; Burdisso, Ricardo A.

1994-01-01

An analytical model has been developed to predict the resulting far field radiation from a turbofan engine inlet. A feedforward control algorithm was simulated to predict the controlled far field radiation from the destructive combination of fan noise and secondary control sources. Numerical results were developed for two system configurations, with the resulting controlled far field radiation patterns showing varying degrees of attenuation and spillover. With one axial station of twelve control sources and error sensors with equal relative angular positions, nearly global attenuation is achieved. Shifting the angular position of one error sensor resulted in an increase of spillover to the extreme sidelines. The complex control inputs for each configuration was investigated to identify the structure of the wave pattern created by the control sources, giving an indication of performance of the system configuration. It is deduced that the locations of the error sensors and the control source configuration are equally critical to the operation of the active noise control system.

High-frequency video capture and a computer program with frame-by-frame angle determination functionality as tools that support judging in artistic gymnastics.

PubMed

Omorczyk, Jarosław; Nosiadek, Leszek; Ambroży, Tadeusz; Nosiadek, Andrzej

2015-01-01

The main aim of this study was to verify the usefulness of selected simple methods of recording and fast biomechanical analysis performed by judges of artistic gymnastics in assessing a gymnast's movement technique. The study participants comprised six artistic gymnastics judges, who assessed back handsprings using two methods: a real-time observation method and a frame-by-frame video analysis method. They also determined flexion angles of knee and hip joints using the computer program. In the case of the real-time observation method, the judges gave a total of 5.8 error points with an arithmetic mean of 0.16 points for the flexion of the knee joints. In the high-speed video analysis method, the total amounted to 8.6 error points and the mean value amounted to 0.24 error points. For the excessive flexion of hip joints, the sum of the error values was 2.2 error points and the arithmetic mean was 0.06 error points during real-time observation. The sum obtained using frame-by-frame analysis method equaled 10.8 and the mean equaled 0.30 error points. Error values obtained through the frame-by-frame video analysis of movement technique were higher than those obtained through the real-time observation method. The judges were able to indicate the number of the frame in which the maximal joint flexion occurred with good accuracy. Using the real-time observation method as well as the high-speed video analysis performed without determining the exact angle for assessing movement technique were found to be insufficient tools for improving the quality of judging.

Spectroscopic ellipsometer based on direct measurement of polarization ellipticity.

PubMed

Watkins, Lionel R

2011-06-20

A polarizer-sample-Wollaston prism analyzer ellipsometer is described in which the ellipsometric angles ψ and Δ are determined by direct measurement of the elliptically polarized light reflected from the sample. With the Wollaston prism initially set to transmit p- and s-polarized light, the azimuthal angle P of the polarizer is adjusted until the two beams have equal intensity. This condition yields ψ=±P and ensures that the reflected elliptically polarized light has an azimuthal angle of ±45° and maximum ellipticity. Rotating the Wollaston prism through 45° and adjusting the analyzer azimuth until the two beams again have equal intensity yields the ellipticity that allows Δ to be determined via a simple linear relationship. The errors produced by nonideal components are analyzed. We show that the polarizer dominates these errors but that for most practical purposes, the error in ψ is negligible and the error in Δ may be corrected exactly. A native oxide layer on a silicon substrate was measured at a single wavelength and multiple angles of incidence and spectroscopically at a single angle of incidence. The best fit film thicknesses obtained were in excellent agreement with those determined using a traditional null ellipsometer.

Co-operation of digital nonlinear equalizers and soft-decision LDPC FEC in nonlinear transmission.

PubMed

Tanimura, Takahito; Oda, Shoichiro; Hoshida, Takeshi; Aoki, Yasuhiko; Tao, Zhenning; Rasmussen, Jens C

2013-12-30

We experimentally and numerically investigated the characteristics of 128 Gb/s dual polarization - quadrature phase shift keying signals received with two types of nonlinear equalizers (NLEs) followed by soft-decision (SD) low-density parity-check (LDPC) forward error correction (FEC). Successful co-operation among SD-FEC and NLEs over various nonlinear transmissions were demonstrated by optimization of parameters for NLEs.

Prediction of acoustic feature parameters using myoelectric signals.

PubMed

Lee, Ki-Seung

2010-07-01

It is well-known that a clear relationship exists between human voices and myoelectric signals (MESs) from the area of the speaker's mouth. In this study, we utilized this information to implement a speech synthesis scheme in which MES alone was used to predict the parameters characterizing the vocal-tract transfer function of specific speech signals. Several feature parameters derived from MES were investigated to find the optimal feature for maximization of the mutual information between the acoustic and the MES features. After the optimal feature was determined, an estimation rule for the acoustic parameters was proposed, based on a minimum mean square error (MMSE) criterion. In a preliminary study, 60 isolated words were used for both objective and subjective evaluations. The results showed that the average Euclidean distance between the original and predicted acoustic parameters was reduced by about 30% compared with the average Euclidean distance of the original parameters. The intelligibility of the synthesized speech signals using the predicted features was also evaluated. A word-level identification ratio of 65.5% and a syllable-level identification ratio of 73% were obtained through a listening test.

Potential Seasonal Terrestrial Water Storage Monitoring from GPS Vertical Displacements: A Case Study in the Lower Three-Rivers Headwater Region, China

PubMed Central

Zhang, Bao; Yao, Yibin; Fok, Hok Sum; Hu, Yufeng; Chen, Qiang

2016-01-01

This study uses the observed vertical displacements of Global Positioning System (GPS) time series obtained from the Crustal Movement Observation Network of China (CMONOC) with careful pre- and post-processing to estimate the seasonal crustal deformation in response to the hydrological loading in lower three-rivers headwater region of southwest China, followed by inferring the annual EWH changes through geodetic inversion methods. The Helmert Variance Component Estimation (HVCE) and the Minimum Mean Square Error (MMSE) criterion were successfully employed. The GPS inferred EWH changes agree well qualitatively with the Gravity Recovery and Climate Experiment (GRACE)-inferred and the Global Land Data Assimilation System (GLDAS)-inferred EWH changes, with a discrepancy of 3.2–3.9 cm and 4.8–5.2 cm, respectively. In the research areas, the EWH changes in the Lancang basin is larger than in the other regions, with a maximum of 21.8–24.7 cm and a minimum of 3.1–6.9 cm. PMID:27657064

Can we improve clinical prediction of at-risk older drivers?

PubMed Central

Bowers, Alex R.; Anastasio, R. Julius; Sheldon, Sarah S.; O’Connor, Margaret G.; Hollis, Ann M.; Howe, Piers D.; Horowitz, Todd S.

2013-01-01

Objectives To conduct a pilot study to evaluate the predictive value of the Montreal Cognitive Assessment test (MoCA) and a brief test of multiple object tracking (MOT) relative to other tests of cognition and attention in identifying at-risk older drivers, and to determine which combination of tests provided the best overall prediction. Methods Forty-seven currently-licensed drivers (58 to 95 years), primarily from a clinical driving evaluation program, participated. Their performance was measured on: (1) a screening test battery, comprising MoCA, MOT, MiniMental State Examination (MMSE), Trail-Making Test, visual acuity, contrast sensitivity, and Useful Field of View (UFOV); and (2) a standardized road test. Results Eighteen participants were rated at-risk on the road test. UFOV subtest 2 was the best single predictor with an area under the curve (AUC) of .84. Neither MoCA nor MOT was a better predictor of the at-risk outcome than either MMSE or UFOV, respectively. The best four-test combination (MMSE, UFOV subtest 2, visual acuity and contrast sensitivity) was able to identify at-risk drivers with 95% specificity and 80% sensitivity (.91 AUC). Conclusions Although the best four-test combination was much better than a single test in identifying at-risk drivers, there is still much work to do in this field to establish test batteries that have both high sensitivity and specificity. PMID:23954688

Habitual sugar intake and cognitive function among middle-aged and older Puerto Ricans without diabetes

PubMed Central

Ye, Xingwang; Gao, Xiang; Scott, Tammy; Tucker, Katherine L.

2016-01-01

Intake of added sugars, mainly fructose and sucrose, has been associated with risk factors for cognitive impairment, such as obesity, the metabolic syndrome and type 2 diabetes. The objective of this analysis was to examine whether habitual intakes of total sugars, added sugars, sugar-sweetened beverages or sweetened solid foods are associated with cognitive function. The present study included 737 participants without diabetes, aged 45–75 years, from the Boston Puerto Rican Health Study, 2004–9. Cognitive function was measured with a battery of seven tests: Mini-Mental State Examination (MMSE), word list learning, digit span, clock drawing, figure copying, and Stroop and verbal fluency tests. Usual dietary intake was assessed with a validated FFQ. Greater intakes of total sugars, added sugars and sugar-sweetened beverages, but not of sugar-sweetened solid foods, were significantly associated with lower MMSE score, after adjusting for covariates. Adjusted OR for cognitive impairment (MMSE score <24) were 2·23 (95 % CI 1·24, 3·99) for total sugars and 2·28 (95 % CI 1·26, 4·14) for added sugars, comparing the highest with lowest intake quintiles. Greater intake of total sugars was also significantly associated with lower word list learning score. In conclusion, higher sugar intake appears to be associated with lower cognitive function, but longitudinal studies are needed to clarify the direction of causality. PMID:21736803

Effect of music intervention on the cognitive and depression status of senior apartment residents in Taiwan

PubMed Central

Tai, Shu-Yu; Wang, Ling-Chun; Yang, Yuan-Han

2015-01-01

Objective To identify the effect of music intervention on cognitive function and depression status of residents in senior citizen apartments based on the existing evidence regarding music therapy. Methods An experimental study was conducted from November 2008 to December 2009. Sixty healthy senior apartment residents over 65 years of age were recruited and separated into two groups. According to their opinion, 41 took part in the music intervention group and 19 in the comparison group. The music intervention involved Buddhist hymns. The short-term effects were evaluated based on the measurement of cognitive function and depression level using the Mini-Mental State Examination (MMSE) and the Geriatric Depression Scale-short form (GDS-SF) at the baseline, 1 month, and 4 months. Results The means of the initial and the 1-month MMSE and GDS-SF scores did not differ between the two groups. The 4-month MMSE score significantly declined compared with the initial level in the comparison group, whereas no significant change was observed in the experimental group. Moreover, the 4-month GDS-SF score significantly improved in both groups compared with the initial level. Conclusion Music intervention may postpone cognitive decline in healthy residents preferring Buddhist hymns in the senior citizen apartments in 4 months follow-up, and intense contact with participants may improve their mood status. PMID:26109859

Dietary Patterns Associated with Cognitive Function among the Older People in Underdeveloped Regions: Finding from the NCDFaC Study.

PubMed

Yin, Zhaoxue; Chen, Jing; Zhang, Jian; Ren, Zeping; Dong, Kui; Kraus, Virginia B; Wang, Zhuoqun; Zhang, Mei; Zhai, Yi; Song, Pengkun; Zhao, Yanfang; Pang, Shaojie; Mi, Shengquan; Zhao, Wenhua

2018-04-09

Although dietary patterns are crucial to cognitive function, associations of dietary patterns with cognitive function have not yet been fully understood. This cross-sectional study explored dietary patterns associated with cognitive function among the older adults in underdeveloped regions, using 1504 community-dwelling older adults aged 60 and over. Diet was assessed using a food frequency questionnaire and 24-h dietary recall. Factor analysis was used to extract dietary patterns. Global cognitive function was assessed using the Mini-Mental State Examination (MMSE). Two dietary patterns, a "mushroom, vegetable, and fruits" (MVF) pattern and a "meat and soybean products" (MS) pattern, were identified. The MVF pattern, characterized by high consumption of mushrooms, vegetables, and fruits was significantly positively associated with cognitive function ( p < 0.05), with an odds ratio of (95% CIs) 0.60 (0.38, 0.94) for cognitive impairment and β (95% CIs) 0.15 (0.02, 0.29) for -log (31-MMSE score). The MS pattern, characterized by high consumption of soybean products and meat, was also associated with better cognitive function, with an odds ratio of 0.47 (95% CIs 0.30, 0.74) for cognitive impairment and β (95% CIs) 0.34 (0.21, 0.47) for -log (31-MMSE score). Our results suggested that both the MVF and MS patterns were positively associated with better cognitive function among older adults in underdeveloped regions.

Correlation or Limits of Agreement? Applying the Bland-Altman Approach to the Comparison of Cognitive Screening Instruments.

PubMed

Larner, A J

2016-01-01

Calculation of correlation coefficients is often undertaken as a way of comparing different cognitive screening instruments (CSIs). However, test scores may correlate but not agree, and high correlation may mask lack of agreement between scores. The aim of this study was to use the methodology of Bland and Altman to calculate limits of agreement between the scores of selected CSIs and contrast the findings with Pearson's product moment correlation coefficients between the test scores of the same instruments. Datasets from three pragmatic diagnostic accuracy studies which examined the Mini-Mental State Examination (MMSE) vs. the Montreal Cognitive Assessment (MoCA), the MMSE vs. the Mini-Addenbrooke's Cognitive Examination (M-ACE), and the M-ACE vs. the MoCA were analysed to calculate correlation coefficients and limits of agreement between test scores. Although test scores were highly correlated (all >0.8), calculated limits of agreement were broad (all >10 points), and in one case, MMSE vs. M-ACE, was >15 points. Correlation is not agreement. Highly correlated test scores may conceal broad limits of agreement, consistent with the different emphases of different tests with respect to the cognitive domains examined. Routine incorporation of limits of agreement into diagnostic accuracy studies which compare different tests merits consideration, to enable clinicians to judge whether or not their agreement is close. © 2016 S. Karger AG, Basel.

Cognitive and physical functions related to the level of supervision and dependence in the toileting of stroke patients.

PubMed

Sato, Atsushi; Okuda, Yutaka; Fujita, Takaaki; Kimura, Norihiko; Hoshina, Noriyuki; Kato, Sayaka; Tanaka, Shigenari

2016-01-01

This study aimed to clarify which cognitive and physical factors are associated with the need for toileting assistance in stroke patients and to calculate cut-off values for discriminating between independent supervision and dependent toileting ability. This cross-sectional study included 163 first-stroke patients in nine convalescent rehabilitation wards. Based on their FIM Ⓡ instrument score for toileting, the patients were divided into an independent-supervision group and a dependent group. Multiple logistic regression analysis and receiver operating characteristic analysis were performed to identify factors related to toileting performance. The Minimental State Examination (MMSE); the Stroke Impairment Assessment Set (SIAS) score for the affected lower limb, speech, and visuospatial functions; and the Functional Assessment for Control of Trunk (FACT) were analyzed as independent variables. The multiple logistic regression analysis showed that the FIM Ⓡ instrument score for toileting was associated with the SIAS score for the affected lower limb function, MMSE, and FACT. On receiver operating characteristic analysis, the SIAS score for the affected lower limb function cut-off value was 8/7 points, the MMSE cut-off value was 25/24 points, and the FACT cut-off value was 14/13 points. Affected lower limb function, cognitive function, and trunk function were related with the need for toileting assistance. These cut-off values may be useful for judging whether toileting assistance is needed in stroke patients.

Thal Amyloid Stages Do Not Significantly Impact the Correlation Between Neuropathological Change and Cognition in the Alzheimer Disease Continuum.

PubMed

Serrano-Pozo, Alberto; Qian, Jing; Muzikansky, Alona; Monsell, Sarah E; Montine, Thomas J; Frosch, Matthew P; Betensky, Rebecca A; Hyman, Bradley T

2016-06-01

The 2012 neuropathological criteria for the diagnosis of Alzheimer disease (AD) summarize the extent of AD neuropathological change with an ABC score, which is a composite of the Thal stage of amyloid deposition (A), the Braak stage of neurofibrillary tangles (NFTs) (B), and the CERAD neuritic plaque score (C). NFTs and neuritic plaques are well-established contributors to cognitive impairment, but whether the Thal amyloid stage independently predicts antemortem cognition remains unknown. We used the National Alzheimer's Coordinating Center autopsy data set to build adjacent-categories logit regression models with CDR-SOB and Mini-Mental State Examination (MMSE) scores as cognitive outcome variables. Increasing CERAD scores were independently associated with higher CDR-SOB scores, whereas increasing Braak NFT stages predicted both higher CDR-SOB and lower MMSE scores. Increasing Thal amyloid stages were not significantly independently associated with either outcome measure. Increasing ABC scores predicted higher CDR-SOB and lower MMSE scores. These results raise the possibility that Thal amyloid stages do not substantially contribute to predicting antemortem cognition compared to CERAD neuritic plaque scores and Braak NFT stages, and suggest that the diffuse amyloid deposits participating in the assignment of Thal amyloid stages are neutral with respect to clinically detectable cognitive and functional changes. © 2016 American Association of Neuropathologists, Inc. All rights reserved.

Habitual sugar intake and cognitive function among middle-aged and older Puerto Ricans without diabetes.

PubMed

Ye, Xingwang; Gao, Xiang; Scott, Tammy; Tucker, Katherine L

2011-11-01

Intake of added sugars, mainly fructose and sucrose, has been associated with risk factors for cognitive impairment, such as obesity, the metabolic syndrome and type 2 diabetes. The objective of this analysis was to examine whether habitual intakes of total sugars, added sugars, sugar-sweetened beverages or sweetened solid foods are associated with cognitive function. The present study included 737 participants without diabetes, aged 45-75 years, from the Boston Puerto Rican Health Study, 2004-9. Cognitive function was measured with a battery of seven tests: Mini-Mental State Examination (MMSE), word list learning, digit span, clock drawing, figure copying, and Stroop and verbal fluency tests. Usual dietary intake was assessed with a validated FFQ. Greater intakes of total sugars, added sugars and sugar-sweetened beverages, but not of sugar-sweetened solid foods, were significantly associated with lower MMSE score, after adjusting for covariates. Adjusted OR for cognitive impairment (MMSE score < 24) were 2.23 (95 % CI 1.24, 3.99) for total sugars and 2.28 (95 % CI 1.26, 4.14) for added sugars, comparing the highest with lowest intake quintiles. Greater intake of total sugars was also significantly associated with lower word list learning score. In conclusion, higher sugar intake appears to be associated with lower cognitive function, but longitudinal studies are needed to clarify the direction of causality.

Optical Coherence Tomography Noise Reduction Using Anisotropic Local Bivariate Gaussian Mixture Prior in 3D Complex Wavelet Domain

PubMed Central

Sonka, Milan; Abramoff, Michael D.

2013-01-01

In this paper, MMSE estimator is employed for noise-free 3D OCT data recovery in 3D complex wavelet domain. Since the proposed distribution for noise-free data plays a key role in the performance of MMSE estimator, a priori distribution for the pdf of noise-free 3D complex wavelet coefficients is proposed which is able to model the main statistical properties of wavelets. We model the coefficients with a mixture of two bivariate Gaussian pdfs with local parameters which are able to capture the heavy-tailed property and inter- and intrascale dependencies of coefficients. In addition, based on the special structure of OCT images, we use an anisotropic windowing procedure for local parameters estimation that results in visual quality improvement. On this base, several OCT despeckling algorithms are obtained based on using Gaussian/two-sided Rayleigh noise distribution and homomorphic/nonhomomorphic model. In order to evaluate the performance of the proposed algorithm, we use 156 selected ROIs from 650 × 512 × 128 OCT dataset in the presence of wet AMD pathology. Our simulations show that the best MMSE estimator using local bivariate mixture prior is for the nonhomomorphic model in the presence of Gaussian noise which results in an improvement of 7.8 ± 1.7 in CNR. PMID:24222760

An Expert System for the Evaluation of Cost Models

DTIC Science & Technology

1990-09-01

contrast to the condition of equal error variance, called homoscedasticity. (Reference: Applied Linear Regression Models by John Neter - page 423...normal. (Reference: Applied Linear Regression Models by John Neter - page 125) Click Here to continue -> Autocorrelation Click Here for the index - Index...over time. Error terms correlated over time are said to be autocorrelated or serially correlated. (REFERENCE: Applied Linear Regression Models by John

Performance of optimum detector structures for noisy intersymbol interference channels

NASA Technical Reports Server (NTRS)

Womer, J. D.; Fritchman, B. D.; Kanal, L. N.

1971-01-01

The errors which arise in transmitting digital information by radio or wireline systems because of additive noise from successively transmitted signals interfering with one another are described. The probability of error and the performance of optimum detector structures are examined. A comparative study of the performance of certain detector structures and approximations to them, and the performance of a transversal equalizer are included.

HyDEn: A Hybrid Steganocryptographic Approach for Data Encryption Using Randomized Error-Correcting DNA Codes

PubMed Central

Regoui, Chaouki; Durand, Guillaume; Belliveau, Luc; Léger, Serge

2013-01-01

This paper presents a novel hybrid DNA encryption (HyDEn) approach that uses randomized assignments of unique error-correcting DNA Hamming code words for single characters in the extended ASCII set. HyDEn relies on custom-built quaternary codes and a private key used in the randomized assignment of code words and the cyclic permutations applied on the encoded message. Along with its ability to detect and correct errors, HyDEn equals or outperforms existing cryptographic methods and represents a promising in silico DNA steganographic approach. PMID:23984392

Demand Controlled Economizer Cycles: A Direct Digital Control Scheme for Heating, Ventilating, and Air Conditioning Systems,

DTIC Science & Technology

1984-05-01

Control Ignored any error of 1/10th degree or less. This was done by setting the error term E and the integral sum PREINT to zero If then absolute value of...signs of two errors jeq tdiff if equal, jump clr @preint else zero integal sum tdiff mov @diff,rl fetch absolute value of OAT-RAT ci rl,25 is...includes a heating coil and thermostatic control to maintain the air in this path at an elevated temperature, typically around 80 degrees Farenheit (80 F

Response Surface Analysis of Experiments with Random Blocks

DTIC Science & Technology

1988-09-01

partitioned into a lack of fit sum of squares, SSLOF, and a pure error sum of squares, SSPE . The latter is obtained by pooling the pure error sums of squares...from the blocks. Tests concerning the polynomial effects can then proceed using SSPE as the error term in the denominators of the F test statistics. 3.2...the center point in each of the three blocks is equal to SSPE = 2.0127 with 5 degrees of freedom. Hence, the lack of fit sum of squares is SSLoF

6.4 Tb/s (32 × 200 Gb/s) WDM direct-detection transmission with twin-SSB modulation and Kramers-Kronig receiver

NASA Astrophysics Data System (ADS)

Zhu, Yixiao; Jiang, Mingxuan; Ruan, Xiaoke; Chen, Zeyu; Li, Chenjia; Zhang, Fan

2018-05-01

We experimentally demonstrate 6.4 Tb/s wavelength division multiplexed (WDM) direct-detection transmission based on Nyquist twin-SSB modulation over 25 km SSMF with bit error rates (BERs) below the 20% hard-decision forward error correction (HD-FEC) threshold of 1.5 × 10-2. The two sidebands of each channel are separately detected using Kramers-Kronig receiver without MIMO equalization. We also carry out numerical simulations to evaluate the system robustness against I/Q amplitude imbalance, I/Q phase deviation and the extinction ratio of modulator, respectively. Furthermore, we show in simulation that the requirement of steep edge optical filter can be relaxed if multi-input-multi-output (MIMO) equalization between the two sidebands is used.

A Two-Stage Approach for Improving the Convergence of Least-Mean-Square Adaptive Decision-Feedback Equalizers in the Presence of Severe Narrowband Interference

NASA Astrophysics Data System (ADS)

Batra, Arun; Zeidler, James R.; Beex, A. A. Louis

2007-12-01

It has previously been shown that a least-mean-square (LMS) decision-feedback filter can mitigate the effect of narrowband interference (L.-M. Li and L. Milstein, 1983). An adaptive implementation of the filter was shown to converge relatively quickly for mild interference. It is shown here, however, that in the case of severe narrowband interference, the LMS decision-feedback equalizer (DFE) requires a very large number of training symbols for convergence, making it unsuitable for some types of communication systems. This paper investigates the introduction of an LMS prediction-error filter (PEF) as a prefilter to the equalizer and demonstrates that it reduces the convergence time of the two-stage system by as much as two orders of magnitude. It is also shown that the steady-state bit-error rate (BER) performance of the proposed system is still approximately equal to that attained in steady-state by the LMS DFE-only. Finally, it is shown that the two-stage system can be implemented without the use of training symbols. This two-stage structure lowers the complexity of the overall system by reducing the number of filter taps that need to be adapted, while incurring a slight loss in the steady-state BER.

L'effet Doppler et le décalage vers le rouge en mécanique rationnelle: applications et verifications experimentales.

PubMed

Loiseaus, J

1968-07-01

Shifts z and z' toward the red of the galaxy NGC 5668 for a beam of 21 cm, z measured in radioastronomy with a frequency meter and z' measured in optics with a spectrograph, not being equal, it follows that the speed of light from a galaxy c ' is not equal to that of a galaxy c which is measured on earth from stationary source. The Doppler empirical formula cannot be explained in classical mechanics since it is in contradiction with it. As for the theory of relativity c ' = c from a postulate and z' = z. If we consider the universe represented on a three-dimensional space (H), non-Euclidian, with Euclidian connection plunged in a Riemannine four-dimension space (E), a certain universal time, like that of an astronomer, can be defined and its course calculated in relation to this time: it will necessarily be confounded with the atomic clock time, but c ' not equal c and z' not equal z: the Doppler formula is not accurate. However, c ' and c as well as z' and z are so close in all the experiments carried out on earth, even when an artificial satellite is used, that the errors made in using the Doppler formula are clearly inferior to experimental errors.

Spatial range of illusory effects in Müller-Lyer figures.

PubMed

Predebon, J

2001-11-01

The spatial range of the illusory effects in Müller-Lyer (M-L) figures was examined in three experiments. Experiments 1 and 2 assessed the pattern of bisection errors along the shaft of the standard or double-angle (experiment 1) and the single-angle (experiment 2) M-L figures: Subjects bisected the shaft and the resulting two half-segments of the shaft to produce apparently equal quarters, and then each of the quarters to produce eight equal-appearing segments. The bisection judgments of each segment were referenced to the segment's physical midpoints. The expansion or wings-out and the contraction or wings-in figures yielded similar patterns of bisection errors. For the standard M-L figures, there were significant errors in bisecting each half, and each end-quarter, but not the two central quarters of the shaft. For the single-angle M-L figures, there were significant errors in bisecting the length of the shaft, the half-segment, and the quarter, of the shaft adjacent to the vertex but not the second quarter from the vertex nor in dividing the half of the shaft at the open end of the figure into four equal intervals. Experiment 3 assessed the apparent length of the half-segment of the shaft at the open end of the single-angle figures. Length judgments were unaffected by the vertex at the opposite end of the shaft. Taken together, the results indicate that the length distortions in both the standard and single-angle M-L figures are not uniformly distributed along the shaft but rather are confined mainly to the quarters adjacent to the vertices. The present findings imply that theories of the M-L illusion which assume uniform expansion or contraction of the shafts are incomplete.

Multiple diabetic complications, as well as impaired physical and mental function, are associated with declining balance function in older persons with diabetes mellitus

PubMed Central

Hong, Xiufang; Chen, Xujiao; Chu, Jiaojiao; Shen, Shanshan; Chai, Qichen; Lou, Gaobo; Chen, Lingyan

2017-01-01

Objective To investigate whether there is a difference in balance function between older persons with and without diabetes mellitus (DM), and to identify whether mediating factors, such as diabetic complications, Instrumental Activities of Daily Living (IADL) score, Mini-Mental State Examination (MMSE) score, as well as hemoglobin A1c (HbA1c), fasting plasma glucose (FPG), serum total cholesterol (TC), triglycerides (TG), and low-density lipoprotein (LDL), are associated with balance function in older persons with DM. Methods In this cross-sectional study, a total of 208 older persons were divided into a DM group (n=80) and a control group who did not have DM (n=128). Balance function was evaluated with the Tinetti performance-oriented mobility assessment (POMA), which includes balance and gait subscales. Activities of daily living (ADL), IADL, and the MMSE were also measured. Fall incidents in last 12 months, the use of walking aids, fear of falling, comorbidities, and polypharmacy were recorded. Diabetic complications were recorded, and HbA1c, FPG, TC, TG, and LDL were measured in the patients of the DM group. Results Fall incidents in last 12 months were higher in the DM group than in the control group (P<0.01). POMA score as well as ADL and IADL scores were lower in the diabetic group than the control group (P<0.05). Within the diabetic group, the POMA score was positively related to the ADL score (odds ratio [OR], 11.7; 95% confidence interval [CI], 3.076–44.497; P<0.01), IADL score (OR, 16.286; 95% CI, 4.793–55.333; P<0.01), and MMSE score (OR, 10.524; 95% CI, 2.764–40.074; P<0.01), but was negatively related to age (OR, 7.707; 95% CI, 2.035–29.185; P<0.01) and diabetic complication (OR, 6.667; 95% CI, 2.279–19.504; P<0.01). Also, within the DM group, the decreased POMA score was associated with multiple diabetic complications (OR, 5.977; 95% CI, 1.378–25.926; P<0.05), decreased IADL score (OR, 10.288; 95% CI, 2.410–43.915; P<0.01), and MMSE score (OR, 13.757; 95% CI, 2.556–74.048; P<0.01). Conclusion Multiple diabetic complications, lower MMSE, ADL, and IADL scores were associated with declining balance function in the older persons with DM. These findings can alert physicians to detect and intervene earlier on declining balance in older persons with DM. PMID:28182146

Differential efficacy of treatment with acetylcholinesterase inhibitors in patients with mild and moderate Alzheimer's disease over a 6-month period.

PubMed

López-Pousa, S; Turon-Estrada, A; Garre-Olmo, J; Pericot-Nierga, I; Lozano-Gallego, M; Vilalta-Franch, M; Hernández-Ferràndiz, M; Morante-Muñoz, V; Isern-Vila, A; Gelada-Batlle, E; Majó-Llopart, J

2005-01-01

There are various anticholinesterase inhibitors (AChEIs) for the symptomatic treatment of mild to moderate Alzheimer's disease (AD). All AChEIs have shown greater efficacy than placebo in randomized, double-blind, parallel-group clinical trials. No differential studies have yet been made of the efficacy between all AChEIs. The study aims to determine the differential efficacy of the AChEIs with respect to a historical sample of patients with AD that were not treated with AChEIs. An open-label, prospective, observational study with a retrospective control group was undertaken to examine the evolution of the cognitive function over a 6-month period. The patients were assessed with the Mini-Mental State Examination (MMSE) at study entry and at 6 months. A general linear model was applied for repeated measurements with the MMSE score as the dependent variable, treatment type as an independent variable and the severity of the deterioration, age and the MMSE baseline score as covariables. Of the sample of 147 patients, 40 initiated treatment with donepezil, 32 with galantamine, 30 with rivastigmine and 45 were part of a historical sample of the memory clinic patients between 1991 and 1996 that had not been treated with AChEIs. The average age was 73.7 years (SD = 6.9; range = 52-86), 67.3% were women, 78.2% of the cases were mild and the MMSE baseline score was 18.1 points (range = 11-27). No significant intergroup differences were observed in these variables. The average doses of donepezil, galantamine and rivastigmine were 5.87 mg/day (SD = 1.92), 14.81 mg/day (SD = 6.25) and 6.41 mg/day (SD = 1.82), respectively. At 6 months, the difference in the MMSE score with respect to the untreated group was 1.6 points for donepezil (95% CI 0.79-2.37; p < 0.001), 0.99 points for galantamine (95% CI 0.14-1.85; p = 0.01) and 0.90 points for rivastigmine (95% CI 0.05-1.74; p = 0.03). No significant differences were observed in the efficacy among the groups treated with AChEIs (p > 0.05). Treatment with AChEIs significantly delays the global cognitive impairment associated with AD for at least 6 months. Our study found no significant differences in efficacy between donepezil, galantamine and rivastigmine. Further studies in the context of daily clinical practice will determine the clinical significance of the changes observed. An important variability of the response to the treatment was observed in treated patients. Copyright 2005 S. Karger AG, Basel.

The architecture of blind equalizer for MIMO free space optical communication system

NASA Astrophysics Data System (ADS)

Li, Hongwei; Huang, Yongmei

2016-10-01

The free space optical (FSO) communication system has attracted many researchers from different countries, owning to its advantages such as high security, high speed and anti-interference. Among all kinds of the channels of the FSO communication system, the atmosphere channel is very difficult to deal with for two typical disadvantages at least. The one is the scintillation of the optical carrier intensity caused by the atmosphere turbulence and the other is the multipath effect by the optical scattering. A lot of studies have shown that the MIMO (Multiple Input Multiple Output) technology can overcome the scintillation of the optical carrier through the atmosphere effectively. So the background of this paper is a MIMO system which includes multiple optical transmitting antennas and multiple optical receiving antennas. A number of particles such as hazes, water droplets and aerosols exit in the atmosphere widely. When optical carrier meets these particles, the scattering phenomenon is inevitable, which leads to the multipath effect. As a result, a optical pulse transmitted by the optical transmitter becomes wider, to some extent, when it gets to the optical receiver due to the multipath effect. If the information transmission rate is quite low, there is less relationship between the multipath effect and the bit error rate (BER) of the communication system. Once the information transmission rate increases to a high level, the multipath effect will produce the problem called inter symbol inference (ISI) seriously and the bit error rate will increase severely. In order to take the advantage of the FSO communication system, the inter symbol inference problem must be solved. So it is necessary to use the channel equalization technology. This paper aims at deciding a equalizer and designing suitable equalization algorithm for a MIMO free space optical communication system to overcome the serious problem of bit error rate. The reliability and the efficiency of communication are two important indexes. For a MIMO communication system, there are two typical equalization methods. The first method, every receiving antenna has an independent equalizer without the information derived from the other receiving antennas. The second, the information derived from all of the receiving antennas mixes with each other, according to some definite rules, which is called space-time equalization. The former is discussed in this paper. The equalization algorithm concludes training mode and non training mode. The training mode needs training codes transmitted by the transmitter during the whole communication process and this mode reduces the communication efficiency more or less. In order to improve the communication efficiency, the blind equalization algorithm, a non training mode, is used to solve the parameter of the equalizer. In this paper, firstly, the atmosphere channel is described focusing on the scintillation and multipath effect of the optical carrier. Then, the structure of a equalizer of MIMO free space optical communication system is introduced. In the next part of this paper, the principle of the blind equalization algorithm is introduced. In addition, the simulation results are showed. In the end of this paper, the conclusions and the future work are discussed.

Low complexity adaptive equalizers for underwater acoustic communications

NASA Astrophysics Data System (ADS)

Soflaei, Masoumeh; Azmi, Paeiz

2014-08-01

Interference signals due to scattering from surface and reflecting from bottom is one of the most important problems of reliable communications in shallow water channels. To solve this problem, one of the best suggested ways is to use adaptive equalizers. Convergence rate and misadjustment error in adaptive algorithms play important roles in adaptive equalizer performance. In this paper, affine projection algorithm (APA), selective regressor APA(SR-APA), family of selective partial update (SPU) algorithms, family of set-membership (SM) algorithms and selective partial update selective regressor APA (SPU-SR-APA) are compared with conventional algorithms such as the least mean square (LMS) in underwater acoustic communications. We apply experimental data from the Strait of Hormuz for demonstrating the efficiency of the proposed methods over shallow water channel. We observe that the values of the steady-state mean square error (MSE) of SR-APA, SPU-APA, SPU-normalized least mean square (SPU-NLMS), SPU-SR-APA, SM-APA and SM-NLMS algorithms decrease in comparison with the LMS algorithm. Also these algorithms have better convergence rates than LMS type algorithm.

Reconstruction of elasticity: a stochastic model-based approach in ultrasound elastography

PubMed Central

2013-01-01

Background The convectional strain-based algorithm has been widely utilized in clinical practice. It can only provide the information of relative information of tissue stiffness. However, the exact information of tissue stiffness should be valuable for clinical diagnosis and treatment. Methods In this study we propose a reconstruction strategy to recover the mechanical properties of the tissue. After the discrepancies between the biomechanical model and data are modeled as the process noise, and the biomechanical model constraint is transformed into a state space representation the reconstruction of elasticity can be accomplished through one filtering identification process, which is to recursively estimate the material properties and kinematic functions from ultrasound data according to the minimum mean square error (MMSE) criteria. In the implementation of this model-based algorithm, the linear isotropic elasticity is adopted as the biomechanical constraint. The estimation of kinematic functions (i.e., the full displacement and velocity field), and the distribution of Young’s modulus are computed simultaneously through an extended Kalman filter (EKF). Results In the following experiments the accuracy and robustness of this filtering framework is first evaluated on synthetic data in controlled conditions, and the performance of this framework is then evaluated in the real data collected from elastography phantom and patients using the ultrasound system. Quantitative analysis verifies that strain fields estimated by our filtering strategy are more closer to the ground truth. The distribution of Young’s modulus is also well estimated. Further, the effects of measurement noise and process noise have been investigated as well. Conclusions The advantage of this model-based algorithm over the conventional strain-based algorithm is its potential of providing the distribution of elasticity under a proper biomechanical model constraint. We address the model-data discrepancy and measurement noise by introducing process noise and measurement noise in our framework, and then the absolute values of Young’s modulus are estimated through the EFK in the MMSE sense. However, the initial conditions, and the mesh strategy will affect the performance, i.e., the convergence rate, and computational cost, etc. PMID:23937814

Reconstruction of elasticity: a stochastic model-based approach in ultrasound elastography.

PubMed

Lu, Minhua; Zhang, Heye; Wang, Jun; Yuan, Jinwei; Hu, Zhenghui; Liu, Huafeng

2013-08-10

The convectional strain-based algorithm has been widely utilized in clinical practice. It can only provide the information of relative information of tissue stiffness. However, the exact information of tissue stiffness should be valuable for clinical diagnosis and treatment. In this study we propose a reconstruction strategy to recover the mechanical properties of the tissue. After the discrepancies between the biomechanical model and data are modeled as the process noise, and the biomechanical model constraint is transformed into a state space representation the reconstruction of elasticity can be accomplished through one filtering identification process, which is to recursively estimate the material properties and kinematic functions from ultrasound data according to the minimum mean square error (MMSE) criteria. In the implementation of this model-based algorithm, the linear isotropic elasticity is adopted as the biomechanical constraint. The estimation of kinematic functions (i.e., the full displacement and velocity field), and the distribution of Young's modulus are computed simultaneously through an extended Kalman filter (EKF). In the following experiments the accuracy and robustness of this filtering framework is first evaluated on synthetic data in controlled conditions, and the performance of this framework is then evaluated in the real data collected from elastography phantom and patients using the ultrasound system. Quantitative analysis verifies that strain fields estimated by our filtering strategy are more closer to the ground truth. The distribution of Young's modulus is also well estimated. Further, the effects of measurement noise and process noise have been investigated as well. The advantage of this model-based algorithm over the conventional strain-based algorithm is its potential of providing the distribution of elasticity under a proper biomechanical model constraint. We address the model-data discrepancy and measurement noise by introducing process noise and measurement noise in our framework, and then the absolute values of Young's modulus are estimated through the EFK in the MMSE sense. However, the initial conditions, and the mesh strategy will affect the performance, i.e., the convergence rate, and computational cost, etc.

A fast-initializing digital equalizer with on-line tracking for data communications

NASA Technical Reports Server (NTRS)

Houts, R. C.; Barksdale, W. J.

1974-01-01

A theory is developed for a digital equalizer for use in reducing intersymbol interference (ISI) on high speed data communications channels. The equalizer is initialized with a single isolated transmitter pulse, provided the signal-to-noise ratio (SNR) is not unusually low, then switches to a decision directed, on-line mode of operation that allows tracking of channel variations. Conditions for optimal tap-gain settings are obtained first for a transversal equalizer structure by using a mean squared error (MSE) criterion, a first order gradient algorithm to determine the adjustable equalizer tap-gains, and a sequence of isolated initializing pulses. Since the rate of tap-gain convergence depends on the eigenvalues of a channel output correlation matrix, convergence can be improved by making a linear transformation on to obtain a new correlation matrix.

Plasma free choline, betaine and cognitive performance: the Hordaland Health Study.

PubMed

Nurk, Eha; Refsum, Helga; Bjelland, Ingvar; Drevon, Christian A; Tell, Grethe S; Ueland, Per M; Vollset, Stein E; Engedal, Knut; Nygaard, Harald A; Smith, David A

2013-02-14

Choline and betaine are nutrients involved in one-carbon metabolism. Choline is essential for neurodevelopment and brain function. We studied the associations between cognitive function and plasma concentrations of free choline and betaine. In a cross-sectional study, 2195 subjects (55 % women), aged 70-74 years, underwent extensive cognitive testing including the Kendrick Object Learning Test (KOLT), Trail Making Test (part A, TMT-A), modified versions of the Digit Symbol Test (m-DST), Block Design (m-BD), Mini-Mental State Examination (m-MMSE) and Controlled Oral Word Association Test (COWAT). Compared with low concentrations, high choline (>8·4 μmol/l) was associated with better test scores in the TMT-A (56·0 v. 61·5, P=0·004), m-DST (10·5 v. 9·8, P=0·005) and m-MMSE (11·5 v. 11·4, P=0·01). A generalised additive regression model showed a positive dose-response relationship between the m-MMSE and choline (P=0·012 from a corresponding linear regression model). Betaine was associated with the KOLT, TMT-A and COWAT, but after adjustments for potential confounders, the associations lost significance. Risk ratios (RR) for poor test performance roughly tripled when low choline was combined with either low plasma vitamin B₁₂ (≤257 pmol/l) concentrations (RR(KOLT)=2·6, 95 % CI 1·1, 6·1; RR(m-MMSE)=2·7, 95 % CI 1·1, 6·6; RR(COWAT)=3·1, 95 % CI 1·4, 7·2) or high methylmalonic acid (MMA) (≥3·95 μmol/l) concentrations (RR(m-BD)=2·8, 95 % CI 1·3, 6·1). Low betaine (≤31·1 μmol/l) combined with high MMA was associated with elevated RR on KOLT (RR(KOLT)=2·5, 95 % CI 1·0, 6·2). Low plasma free choline concentrations are associated with poor cognitive performance. There were significant interactions between low choline or betaine and low vitamin B₁₂ or high MMA on cognitive performance.

Multichannel linear descriptors analysis for event-related EEG of vascular dementia patients during visual detection task.

PubMed

Lou, Wutao; Xu, Jin; Sheng, Hengsong; Zhao, Songzhen

2011-11-01

Multichannel EEG recorded in a task condition could contain more information about cognition. However, that has not been widely investigated in the vascular-dementia (VaD)- related studies. The purpose of this study was to explore the differences of brain functional states between VaD patients and normal controls while performing a detection task. Three multichannel linear descriptors, i.e. spatial complexity (Ω), field strength (Σ) and frequency of field changes (Φ), were applied to analyse four frequency bands (delta, theta, alpha and beta) of multichannel event-related EEG signals for 12 VaD patients (mean age ± SD: 69.25 ± 10.56 years ; MMSE score ± SD: 22.58 ± 4.42) and 12 age-matched healthy subjects (mean age ± SD: 67.17 ± 5.97 years ; MMSE score ± SD: 29.08 ± 0.9). The correlations between the three measures and MMSE scores were also analysed. VaD patients showed a significant higher Ω value in the delta (p = 0.013) and theta (p = 0.021) frequency bands, a lower Σ value (p = 0.011) and a higher Φ (p = 0.008) value in the delta frequency band compared with normal controls. The MMSE scores were negatively correlated with the Ω (r = -0.52, p = 0.01) and Φ (r = -0.47, p = 0.02) values in the delta frequency band. The results indicated the VaD patients presented a reduction of synchronization in the slow frequency band during target detection, and suggested more neurons might be activated in VaD patients compared with normal controls. The Ω and Φ measures in the delta frequency band might be used to evaluate the degree of cognitive dysfunction. The multichannel linear descriptors are promising measures to reveal the differences in brain functions between VaD patients and normal subjects, and could potentially be used to evaluate the degree of cognitive dysfunction in VaD patients. Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Tocopherol in Elder Self-Neglect

NASA Technical Reports Server (NTRS)

Aung, K.; Burnett, J.; Dyer, C.; Smith, S. M.

2009-01-01

Although elder self-neglect is the most common form of elder mistreatment, its pathophysiology is not well understood. Alpha-tocopherol is a lipid soluble antioxidant required for the preservation of cell membranes. Since the association between tocopherol and cognitive impairment in older adults has been described, we explored the possibility of its role in elder self-neglect. OBJECTIVE: (1) To determine whether serum tocopherol levels are associated with elder self-neglect, and (2) to assess the association of serum tocopherol levels and cognitive function in elder self-neglect. METHODS: Serum tocopherol levels were measured in a cohort of 67 self-neglecting elders and 67 matched controls, recruited for the Consortium for Research in Elder Self-neglect of Texas. Pearson s correlation tests were performed to assess bivariate associations between serum tocopherol levels and cognitive function. RESULTS: Mean serum alpha-tocopherol levels were 10.8 +/- 4.7 ug/mL in self-neglect group and 13.0 +/- 4.9 ug/mL in control group (p = 0.006, unpaired student s t-test). None of the participants from either group had alpha-tocopherol level lower than the reference range. Mean serum gamma-tocopherol levels were 2.0 +/- 1.0 ug/mL in self-neglect group and 2.0 +/- 1.1 in control group (p=0.83). Proportion of the elders with gamma-tocopherol level lower than the reference range were 4.5% (3/66) in self-neglect group and 10.4% (7/67) in control group (p=0.32, Fisher s Exact Test). Among the self-neglecting elders, no association was found between serum alpha-tocopherol levels and the Mini-Mental State Examination (MMSE) or the Wolf-Klein Clock Drawing Test (CDT) scores (r =-0.42, p=0.75 for MMSE; r=0.08, p=0.54 for CDT). No association was found between serum gamma-tocopherol levels and the MMSE or the CDT (r=-0.12, p=0.35 for MMSE; r=0.05, p=0.68 for CDT). CONCLUSION: In our sample, neither alpha-tocopherol nor gamma-tocopherol appears to have a role in pathophysiology of elder self-neglect. Nevertheless, significantly lower serum alpha-tocopherol levels in the self neglect group merits further research.

Do Arterial Hemodynamic Parameters Predict Cognitive Decline Over a Period of 2 Years in Individuals Older Than 80 Years Living in Nursing Homes? The PARTAGE Study.

PubMed

Watfa, Ghassan; Benetos, Athanase; Kearney-Schwartz, Anna; Labat, Carlos; Gautier, Sylvie; Hanon, Olivier; Salvi, Paolo; Joly, Laure

2015-07-01

Several studies have highlighted a link between vascular alterations and cognitive decline. The PARTAGE study showed that arterial stiffness as evaluated by carotid-femoral pulse wave velocity (cfPWV) was associated with a more pronounced cognitive decline over a 1-year period in very old frail institutionalized individuals. The aim of the present analysis was to assess the role of hemodynamic parameters, such as blood pressure (BP), heart rate (HR), cfPWV, and central/peripheral pulse pressure amplification (PPA) on cognitive decline over 2 years in very old frail individuals. A total of 682 individuals from the PARTAGE study cohort, aged older than 80 years (mean age at inclusion: 87.5 ± 5.0 years) and living in French and Italian nursing homes, were analyzed. Mini-Mental State Examination (MMSE) score was assessed at baseline (BL) and at the end of the first and second year of follow-up (2y-FU). Those with a decrease in MMSE of 3 or more points between BL and 2y-FU were considered as "decliners." The cfPWV and PPA at baseline were assessed with an arterial tonometer. After adjustment for baseline MMSE, HR, body mass index, age, education level, and activities of daily living (ADLs), cfPWV was higher and PPA lower in "decliners" compared with "nondecliners," whereas BP did not differ between the 2 groups. Logistic multivariate analysis also revealed that high cfPWV, low PPA, high HR, and low ADLs were all determinants of MMSE decline. This 2-year longitudinal study in very old institutionalized individuals shows that arterial stiffness and high HR enabled us to identify subjects at higher risk of cognitive decline, whereas BP alone did not appear to have a significant predictive value. These findings highlight the contribution of vascular determinants in cognitive decline even in this very old population. Copyright © 2015 AMDA - The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

EEG complexity as a biomarker for autism spectrum disorder risk

PubMed Central

2011-01-01

Background Complex neurodevelopmental disorders may be characterized by subtle brain function signatures early in life before behavioral symptoms are apparent. Such endophenotypes may be measurable biomarkers for later cognitive impairments. The nonlinear complexity of electroencephalography (EEG) signals is believed to contain information about the architecture of the neural networks in the brain on many scales. Early detection of abnormalities in EEG signals may be an early biomarker for developmental cognitive disorders. The goal of this paper is to demonstrate that the modified multiscale entropy (mMSE) computed on the basis of resting state EEG data can be used as a biomarker of normal brain development and distinguish typically developing children from a group of infants at high risk for autism spectrum disorder (ASD), defined on the basis of an older sibling with ASD. Methods Using mMSE as a feature vector, a multiclass support vector machine algorithm was used to classify typically developing and high-risk groups. Classification was computed separately within each age group from 6 to 24 months. Results Multiscale entropy appears to go through a different developmental trajectory in infants at high risk for autism (HRA) than it does in typically developing controls. Differences appear to be greatest at ages 9 to 12 months. Using several machine learning algorithms with mMSE as a feature vector, infants were classified with over 80% accuracy into control and HRA groups at age 9 months. Classification accuracy for boys was close to 100% at age 9 months and remains high (70% to 90%) at ages 12 and 18 months. For girls, classification accuracy was highest at age 6 months, but declines thereafter. Conclusions This proof-of-principle study suggests that mMSE computed from resting state EEG signals may be a useful biomarker for early detection of risk for ASD and abnormalities in cognitive development in infants. To our knowledge, this is the first demonstration of an information theoretic analysis of EEG data for biomarkers in infants at risk for a complex neurodevelopmental disorder. PMID:21342500

The development and validation of a carer questionnaire to assess cognitive function in neuropsychiatric patients.

PubMed

Randhawa, Sharan; Walterfang, Mark; Miller, Kathryn; Scholes, Amelia; Mocellin, Ramon; Velakoulis, Dennis

2007-07-01

The carer history is an integral part of the assessment of patients with cognitive impairment. We aimed to develop a comprehensive yet concise carer questionnaire, the CogRisk, which captures actuarial risk variables for cognitive impairment in addition to key symptoms suggestive of cognitive decline in a number of cognitive domains, and to then assess its validity and reliability in a neuropsychiatric population. Carers of patients assessed for cognitive impairment completed the CogRisk, and patients were clinically assessed using the Mini-Mental State Examination (MMSE) and Neuropsychiatry Unit COGnitive assessment tool (NUCOG). Reliability was assessed using test-retest and interrater measures and measures of internal consistency. Construct and concurrent validity was assessed using correlation between total and subscale scores on the CogRisk, total scores on the NUCOG and MMSE, and subscale scores on the NUCOG. Predictive validity was determined using measures of sensitivity and specificity and using receiver operating characteristic (ROC) methods. The CogRisk was completed by all carers in less than 10 min. The total CogRisk score correlated significantly with total MMSE and NUCOG scores (r=-0.511 and -0.563, respectively) and remained highly significant when age and education were controlled for. Internal consistency of CogRisk items was high (alpha=0.943). Intrarater reliability of the CogRisk was high with an intraclass correlation coefficient of .978 (P<.001), and interrater reliability between carers was also high at 0.868 (P<.05). Sensitivity and specificity for the detection of dementia were .70 and .73, respectively, with area under the ROC curve not significantly different from that of the MMSE or NUCOG. The CogRisk is a brief carer-rated tool of a patient's cognitive functioning developed for use within a neuropsychiatric setting. It exhibited good concurrent validity, internal consistency, and interrater and intrarater reliability. The CogRisk also demonstrated good sensitivity and specificity for dementia. The CogRisk provides carer information, which complements the clinical assessment and can be used to focus on direct carer interview.

Efficacy and cognitive side effects of electroconvulsive therapy (ECT) in depressed elderly inpatients with coexisting mild cognitive impairment or dementia.

PubMed

Hausner, Lucrezia; Damian, Marinella; Sartorius, Alexander; Frölich, Lutz

2011-01-01

To study cognitive performance in depressed geriatric inpatients with or without preexisting cognitive impairment who received a first course of electroconvulsive therapy (ECT). Forty-four elderly inpatients with major depressive disorder (ICD-10 criteria) were included in a prospective consecutive case series of a university hospital. The patients were divided into 3 groups (no cognitive impairment [NCI], mild cognitive impairment [MCI], dementia) and rated for cognitive performance with the MMSE before first ECT, after sixth ECT, and 6 weeks and 6 months after ECT termination. Affective symptoms were rated by 21-item Hamilton Depression Rating Scale (HDRS-21) before and 6 weeks after ECT. Analysis of variance or Kruskal-Wallis tests on ECT-induced MMSE and HDRS-21 score changes were compared to baseline. Binary logistic regression was used for predictor analysis. The study was conducted from April 2004 to April 2008. After initial nonsignificant cognitive deterioration in all 3 groups, the NCI group improved cognitively 6 weeks (P = .018) and 6 months (P = .027) after ECT. The MCI group improved in cognition 6 months (P = .036) after ECT. In the dementia group, mean MMSE scores also improved numerically over the course of ECT without significance. Dementia patients with antidementia treatment improved in cognition to a clinically relevant extent after the sixth ECT. Dementia subjects without antidementia treatment deteriorated. After the sixth ECT, 70.0% of dementia patients (P = .004) presented a cognitive decline, and 68.8% of MCI patients (P < .001) presented a decline 6 weeks after ECT. Six months after ECT, one-third of the dementia patients (P < .036) still had a cognitive decline. Affective symptoms remitted after ECT in all 3 groups (P < .001). Pre-ECT cognitive deficits were the best predictor of MMSE decline (6 weeks after ECT, P = .007; 6 months after ECT, P = .055). ECT is effective and well tolerated in geriatric depressed inpatients regardless of preexisting cognitive impairment. Cognitive deficits were transient. © Copyright 2011 Physicians Postgraduate Press, Inc.

Cognitive changes under memantine according to vitamin D status in Alzheimer patients: An exposed/unexposed cohort pilot study.

PubMed

Lemire, Pauline; Brangier, Antoine; Beaudenon, Melinda; Duval, Guillaume T; Annweiler, Cedric

2018-01-01

Memantine is a symptomatic treatment that partially prevents cognitive decline in Alzheimer disease (AD). The neuroprotective effects of memantine and vitamin D may potentiate each other, with benefits for cognition. The objective of this exposed/unexposed pilot study was to determine the cognitive changes among AD patients using memantine according to the presence or absence of vitamin D deficiency (VDD). Fifty-eight AD patients followed in a memory clinic during 6 months between 2009 and 2014 (mean±standard deviation, 82.9±5.0years; 56.9%female) were separated into four groups according to VDD (i.e., serum 25-hydroxyvitamin D≤25nM) at M0 and M6 (i.e., Group 1: no VDD-M0, no VDD-M6; Group 2: VDD-M0, no VDD-M6; Group 3: no VDD-M0, VDD-M6; Group 4: VDD-M0, VDD-M6). The 6-month cognitive change was examined with the Mini-Mental State Examination (MMSE) score in the 4 groups according to the use of memantine. Age, gender, body mass index, IADL score, GDS score, and use of pchychoactive drugs were measured at baseline. We found that participants using memantine had a lower MMSE score at M0 compared to those without memantine (P=0.006). After 6 months of follow-up, there was a memantine-related improvement of the MMSE score only in the participants with VDD-M6. This was significant in Group 3 with no VDD-M0 (P=0.039), but not in Group 4 who already had VDD-M0. Similarly, using memantine was associated with a 6-month improvement of MMSE only in Group 3 in whom VDD appeared during the follow-up (β=8.8, P=0.044). In conclusion, the use of memantine was associated with improved cognitive performance after 6 months of treatment in the presence of VDD at M6. Memantine may prevent the cognitive decline that accompanies the onset of VDD, which prompts to give to AD patients a regimen combining both memantine and vitamin D supplements. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bias-field equalizer for bubble memories

NASA Technical Reports Server (NTRS)

Keefe, G. E.

1977-01-01

Magnetoresistive Perm-alloy sensor monitors bias field required to maintain bubble memory. Sensor provides error signal that, in turn, corrects magnitude of bias field. Error signal from sensor can be used to control magnitude of bias field in either auxiliary set of bias-field coils around permanent magnet field, or current in small coils used to remagnetize permanent magnet by infrequent, short, high-current pulse or short sequence of pulses.

Using Thin-Film Thermometers as Heaters in Thermal Control Applications

NASA Technical Reports Server (NTRS)

Cho, Hyung J.; Penanen, Konstantin; Sukhatme, Kalyani G.; Holmes, Warren A.; Courts, Scott

2010-01-01

A cryogenic sensor maintains calibration at approximately equal to 4.2 K to better than 2 mK (< 0.5 percent resistance repeatability) after being heated to approximately equal 40 K with approximately equal 0.5 W power. The sensor withstands 4 W power dissipation when immersed in liquid nitrogen with verified resistance reproducibility of, at worst, 1 percent. The sensor maintains calibration to 0.1 percent after being heated with 1-W power at approximately equal 77 K for a period of 48 hours. When operated with a readout scheme that is capable of mitigating the self-heating calibration errors, this and similar sensors can be used for precision (mK stability) temperature control without the need of separate heaters and associated wiring/cabling.

Learning to classify in large committee machines

NASA Astrophysics Data System (ADS)

O'kane, Dominic; Winther, Ole

1994-10-01

The ability of a two-layer neural network to learn a specific non-linearly-separable classification task, the proximity problem, is investigated using a statistical mechanics approach. Both the tree and fully connected architectures are investigated in the limit where the number K of hidden units is large, but still much smaller than the number N of inputs. Both have continuous weights. Within the replica symmetric ansatz, we find that for zero temperature training, the tree architecture exhibits a strong overtraining effect. For nonzero temperature the asymptotic error is lowered, but it is still higher than the corresponding value for the simple perceptron. The fully connected architecture is considered for two regimes. First, for a finite number of examples we find a symmetry among the hidden units as each performs equally well. The asymptotic generalization error is finite, and minimal for T-->∞ where it goes to the same value as for the simple perceptron. For a large number of examples we find a continuous transition to a phase with broken hidden-unit symmetry, which has an asymptotic generalization error equal to zero.

A theory for predicting composite laminate warpage resulting from fabrication

NASA Technical Reports Server (NTRS)

Chamis, C. C.

1974-01-01

Linear laminate theory is used with the moment-curvature relationship to derive equations for predicting end deflections due to warpage without solving the coupled fourth-order partial differential equations of the plate. Composite micro- and macrohyphenmechanics are used with laminate theory to assess the contribution of factors such as ply misorientation, fiber migration, and fiber and/or void volume ratio nonuniformity on the laminate warpage. Using these equations, it was found that a 1 deg error in the orientation angle of one ply was sufficient to produce warpage end deflection equal to two laminate thicknesses in a 10 inch by 10 inch laminate made from 8 ply Mod-I/epoxy. Using a sensitivity analysis on the governing parameters, it was found that a 3 deg fiber migration or a void volume ratio of three percent in some plies is sufficient to produce laminate warpage corner deflection equal to several laminate thicknesses. Tabular and graphical data are presented which can be used to identify possible errors contributing to laminate warpage and/or to obtain an a priori assessment when unavoidable errors during fabrication are anticipated.

Nonlinear filter based decision feedback equalizer for optical communication systems.

PubMed

Han, Xiaoqi; Cheng, Chi-Hao

2014-04-07

Nonlinear impairments in optical communication system have become a major concern of optical engineers. In this paper, we demonstrate that utilizing a nonlinear filter based Decision Feedback Equalizer (DFE) with error detection capability can deliver a better performance compared with the conventional linear filter based DFE. The proposed algorithms are tested in simulation using a coherent 100 Gb/sec 16-QAM optical communication system in a legacy optical network setting.

Differences among Job Positions Related to Communication Errors at Construction Sites

NASA Astrophysics Data System (ADS)

Takahashi, Akiko; Ishida, Toshiro

In a previous study, we classified the communicatio n errors at construction sites as faulty intention and message pattern, inadequate channel pattern, and faulty comprehension pattern. This study seeks to evaluate the degree of risk of communication errors and to investigate differences among people in various job positions in perception of communication error risk . Questionnaires based on the previous study were a dministered to construction workers (n=811; 149 adminis trators, 208 foremen and 454 workers). Administrators evaluated all patterns of communication error risk equally. However, foremen and workers evaluated communication error risk differently in each pattern. The common contributing factors to all patterns wer e inadequate arrangements before work and inadequate confirmation. Some factors were common among patterns but other factors were particular to a specific pattern. To help prevent future accidents at construction sites, administrators should understand how people in various job positions perceive communication errors and propose human factors measures to prevent such errors.

Payload transportation system study

NASA Technical Reports Server (NTRS)

1976-01-01

A standard size set of shuttle payload transportation equipment was defined that will substantially reduce the cost of payload transportation and accommodate a wide range of payloads with minimum impact on payload design. The system was designed to accommodate payload shipments between the level 4 payload integration sites and the launch site during the calendar years 1979-1982. In addition to defining transportation multi-use mission support equipment (T-MMSE) the mode of travel, prime movers, and ancillary equipment required in the transportation process were also considered. Consistent with the STS goals of low cost and the use of standardized interfaces, the transportation system was designed to commercial grade standards and uses the payload flight mounting interfaces for transportation. The technical, cost, and programmatic data required to permit selection of a baseline system of MMSE for intersite movement of shuttle payloads were developed.

The relation of education and cognitive activity to mini-mental state in old age: the role of functional fitness status.

PubMed

Ihle, Andreas; Gouveia, Élvio R; Gouveia, Bruna R; Freitas, Duarte L; Jurema, Jefferson; Ornelas, Rui T; Antunes, António M; Muniz, Bárbara R; Kliegel, Matthias

2018-06-01

It remains unclear so far whether the role of cognitive reserve for cognitive functioning in old age may differ between individuals with low, compared to those with high functional fitness status. Therefore, the present study set out to investigate the relation of education and cognitive leisure activity as key markers of cognitive reserve to mini-mental state in old age (as an indicator of the extent of cognitive impairment) and its interplay with functional fitness status in a large sample of older adults. We assessed MMSE in 701 older adults ( M  = 70.4 years, SD = 6.9, range: 60-91). We measured functional fitness status using the Senior Fitness Test battery and interviewed individuals on their education and cognitive leisure activity. Results showed that better functional fitness status, longer education, and greater engagement in cognitive leisure activity were significantly related to higher MMSE scores. Moderation analyses showed that the relations of education and cognitive leisure activity to MMSE scores were significantly larger in individuals with low, compared to those with high functional fitness status. In conclusion, cognitive functioning in old age may more strongly depend on cognitive reserve accumulated during the life course in older adults with low, compared to those with high functional fitness status. These findings may be explained by cross-domain compensation effects in vulnerable individuals and may (at least partly) account for the large variability in cognitive reserve-cognition relations debated in the literature.

The mini-cog: a cognitive 'vital signs' measure for dementia screening in multi-lingual elderly.

PubMed

Borson, S; Scanlan, J; Brush, M; Vitaliano, P; Dokmak, A

2000-11-01

The Mini-Cog, a composite of three-item recall and clock drawing, was developed as a brief test for discriminating demented from non-demented persons in a community sample of culturally, linguistically, and educationally heterogeneous older adults. All 129 who met criteria for probable dementia based on informant interviews and 120 with no history of cognitive decline were included; 124 were non-English speakers. Sensitivity, specificity, and diagnostic value of the Mini-Cog were compared with those of the Mini-Mental State Exam (MMSE) and Cognitive Abilities Screening Instrument (CASI). The Mini-Cog had the highest sensitivity (99%) and correctly classified the greatest percentage (96%) of subjects. Moreover, its diagnostic value was not influenced by education or language, while that of the CASI was adversely influenced by low education, and both education and language compromised the diagnostic value of the MMSE. Administration time for the Mini-Cog was 3 minutes vs 7 minutes for the MMSE. The Mini-Cog required minimal language interpretation and training to administer, and no test forms of scoring modifications were needed to compensate for the extensive linguistic and educational heterogeneity of the sample. Validation in clinical and population-based samples is warranted, as its brevity and ease of administration suggest that the Mini-Cog might be readily incorporated into general practice and senior care settings as a routine 'cognitive vital signs' measure. Copyright 2000 John Wiley & Sons, Ltd.

Physical, mental, and cognitive function in a convenience sample of centenarians in Australia.

PubMed

Richmond, Robyn L; Law, Jenaleen; Kay-Lambkin, Frances

2011-06-01

To examine the physical, mental, and cognitive function of centenarians. Descriptive study using a structured questionnaire and convenience sampling. Residential care facilities and private dwellings in Australia. A convenience sample of 188 centenarians. The Hospital Anxiety and Depression Scale (HADS) screened for anxiety and depression. The Katz Index of Independence in Activities of Daily Living (Katz ADL) was used to assess functional status. The Quality of Life Scale was used to assess quality of life. The Mini-Mental State Examination (MMSE) was used to screen for dementia. Structured responses were obtained for living arrangement, marital status, social relationships, and supports. Centenarians had regular contact with friends (59%), neighbors (62%), and families (72%); 54% were religious and 43.5% had received social supports. Average MMSE and Katz ADL scores were 21.5 and 3.7, respectively; 45% had scores on the MMSE indicative of dementia, 10% indicated anxiety and 14% depression on the HADS. Participants with poor ratings of health experienced higher rates of anxiety and depression than their healthier counterparts. In this convenience sample of Australian centenarians, anxiety and depression was relatively nonexistent, and most reported a high quality of life. This was despite objective deterioration in functional status, paralleling the aging process, and high dependence on others for everyday tasks. Potentially, this is suggestive of a unique ability within the sample to adapt to aging and its limitations. © 2011, Copyright the Authors. Journal compilation © 2011, The American Geriatrics Society.

Risk Evaluation of Postoperative Delirium Using Comprehensive Geriatric Assessment in Elderly Patients with Esophageal Cancer.

PubMed

Yamamoto, Masaaki; Yamasaki, Makoto; Sugimoto, Ken; Maekawa, Yoshihiro; Miyazaki, Yasuhiro; Makino, Tomoki; Takahashi, Tsuyoshi; Kurokawa, Yukinori; Nakajima, Kiyokazu; Takiguchi, Shuji; Rakugi, Hiromi; Mori, Masaki; Doki, Yuichiro

2016-11-01

The number of geriatric patients with esophageal cancer is increasing in step with the aging of the population. Geriatric patients have a higher risk of postoperative complications, including delirium that can cause a fall or impact survival. Therefore, it is very important that we evaluate risks of postoperative complications before surgery. The aim of this study was to predict postoperative delirium in elderly patients. We retrospectively reviewed the medical records of 91 patients aged 75 years and over who underwent esophagectomy between January 2006 and December 2014. We investigated the association between postoperative delirium and clinicopathological factors, including comprehensive geriatric assessment (CGA). Postoperative delirium developed in 24 (26 %) patients. Postoperative delirium was significantly associated with low mini-mental state examination (MMSE) and high Geriatric Depression Scale 15 (GDS15), which are components of CGA, and psychiatric disorder (P < 0.0001, P = 0.002, and P = 0.017, respectively). With multiple logistic regression analysis, MMSE (odds ratio [OR], 1.4; 95 % confidence interval [CI], 1.2-1.6; P < 0.0001] and GDS15 (OR, 1.3; 95 % CI, 1.1-1.6; P = 0.004) were independently associated with postoperative delirium. Preoperative CGA, especially MMSE and GDS15, was useful for predicting postoperative delirium in elderly patients undergoing esophagectomy for esophageal cancer. Intervention by a multidisciplinary team using CGA might help prevent postoperative delirium.

Parathyroid Hormone Levels and Cognition

NASA Technical Reports Server (NTRS)

Burnett, J.; Smith, S.M.; Aung, K.; Dyer, C.

2009-01-01

Hyperparathyroidism is a well-recognized cause of impaired cognition due to hypercalcemia. However, recent studies have suggested that perhaps parathyroid hormone itself plays a role in cognition, especially executive dysfunction. The purpose of this study was to explore the relationship of parathyroid hormone levels in a study cohort of elders with impaied cognition. Methods: Sixty community-living adults, 65 years of age and older, reported to Adult Protective Services for self-neglect and 55 controls matched (on age, ethnicity, gender and socio-economic status) consented and participated in this study. The research team conducted in-home comprehensive geriatric assessments which included the Mini-mental state exam (MMSE), the 15-item geriatric depression scale (GDS) , the Wolf-Klein clock test and a comprehensive nutritional panel, which included parathyroid hormone and ionized calcium. Students t tests and linear regression analyses were performed to assess for bivariate associations. Results: Self-neglecters (M = 73.73, sd=48.4) had significantly higher PTH levels compared to controls (M =47.59, sd=28.7; t=3.59, df=98.94, p<.01). There was no significant group difference in ionized calcium levels. Overall, PTH was correlated with the MMSE (r=-.323, p=.001). Individual regression analyses revealed a statistically significant correlation between PTH and MMSE in the self-neglect group (r=-.298, p=.024) and this remained significant after controlling for ionized calcium levels in the regression. No significant associations were revealed in the control group or among any of the other cognitive measures. Conclusion: Parathyroid hormone may be associated with cognitive performance.

Risk factors associated with cognitive decline in the elderly with type 2 diabetes: baseline data analysis of the Japanese Elderly Diabetes Intervention Trial.

PubMed

Umegaki, Hiroyuki; Iimuro, Satoshi; Shinozaki, Tomohiro; Araki, Atsushi; Sakurai, Takashi; Iijima, Katsuya; Ohashi, Yasuo; Ito, Hideki

2012-04-01

Recent evidence has shown that type 2 diabetes mellitus (T2DM) in the elderly is a risk factor for cognitive dysfunction or dementia. However, the precise mechanisms have not yet been elucidated. In the current study, we attempted to elucidate the association of clinical indices and diabetic complications at baseline with cognitive declines after 6-year follow up in type 2 diabetic elderly. The subjects were 261 participants who were administered the Mini-Mental State Examination (MMSE) at baseline and after 6 years, at the end of the observation period. The cognitive decline was determined as a 5-point or greater decline in MMSE scores during the observation period. Logistic regression analysis to find the factors associated with cognitive decline, adjusted for age and sex, were carried out, and factors with P-values of less than 0.2 were included in four models of multiple logistic regression analysis. We found that the existence of diabetic nephropathy, higher systolic blood pressure and higher serum triglycerides (or lower high-density lipoprotein cholesterol) at baseline were significantly associated with cognitive declines after 6 years in Japanese elderly diabetics in all four models. The comorbidity of diabetic nephropathy, hypertension and hypertriglyceridemia at baseline were associated with more than 5-point declines in MMSE. Elucidation of the underlying mechanisms of this association is warranted. © 2012 Japan Geriatrics Society.

A population-based study of parkinsonism in an Amish community.

PubMed

Racette, Brad A; Good, Laura M; Kissel, Abigail M; Criswell, Susan R; Perlmutter, Joel S

2009-01-01

Parkinson's disease (PD) is a neurodegenerative disorder with unknown cause. Genetic mutations account for a minority of cases but the role of environmental factors is unclear. We performed a population-based screening for PD in subjects in an Amish community over age 60. PD was diagnosed using standard clinical criteria and the Unified Parkinson Disease Rating Scale motor subsection 3 (UPDRS3). Community prevalence was calculated. We constructed a community pedigree and calculated kinship coefficients, a measure of relatedness between 2 subjects, for every pair of subjects in diagnostic categories: clinically definite PD, UPDRS3 score >9, Mini-Mental State Exam (MMSE) score <25, and normal. Of 262 eligible subjects, 213 agreed to participate, 15 had PD, 43 had MMSE <25, 73 had UPDRS3 >9. The prevalence of PD was 5,703/100,000 with increasing prevalence in every decade of age. Excluding first-degree relatives, normal subjects were more related to each other (0.0102, SD = 0.0266) than subjects with clinically definite PD (0.0054, SD = 0.0100; p = 0.00003), subjects with UPDRS >9 (0.0076, SD = 0.0155; p = 0.00001), and subjects with MMSE <25 (0.0090, SD = 0.0180; p = 0.00003). PD and parkinsonian signs are common in this population and the prevalence increases with age. The finding that subjects with PD were not more related than normal subjects suggests that environmental factors may contribute to the parkinsonian phenotype in this community. Copyright 2009 S. Karger AG, Basel.

[Performance of cognitive brief test in elderly patients with dementia in advanced stage living in an urban community of Lima, Peru].

PubMed

Custodio, Nilton; Alva-Diaz, Carlos; Becerra-Becerra, Yahaira; Montesinos, Rosa; Lira, David; Herrera-Pérez, Eder; Castro-Suárez, Sheila; Cuenca-Alfaro, José; Valeriano-Lorenzo, Elizabeth

2016-01-01

Evaluate the performance of clock drawing test- Manos versión (PDR-M) and Mini Mental State Examination -Peruvian version (MMSE) to detect dementia in a sample based on urban community of Lima, Peru. This study is a secondary analysis database, observational, analytical and cross-sectional, the gold standard was the clinical and the neuropsychological evaluations together. Performance testing individually and in combination were evaluated.. Data were obtained from prevalence study conducted in 2008 in Cercado de Lima. MMSE performance for evaluation of patients with dementia of any kind showed sensitivity of 64,1%, specificity of 84,1%, PPV of 24.4%, NPV of 96.7%, PLR of 4,03 and NLR of 0,43. PDR-M showed sensitivity of 89,3%, specificity of 98,1%, PPV of 79.3%, NPV of 99.1%, PLR of 47,79 and NLR of 0,11. When both tests were applied, and at least one of them was positive, they showed sensitivity 98.1%, specificity 84.1%, PPV of 33.1%, NPV of 99.8%, PLR of 6,17 and NLR of 0,02. When performing separate analysis of Alzheimer-type dementia and non- Alzheimer dementia, the values of the parameters do not differ substantially from those obtained for dementia of any kind. The combination of MMSE and PDR-M show good discriminative ability to detect moderate and severe dementia in population living in urban community in Lima.

Thyroid function abnormalities and cognitive impairment in elderly people: results of the Invecchiare in Chianti study.

PubMed

Ceresini, Graziano; Lauretani, Fulvio; Maggio, Marcello; Ceda, Gian Paolo; Morganti, Simonetta; Usberti, Elisa; Chezzi, Carlo; Valcavi, Rita; Bandinelli, Stefania; Guralnik, Jack M; Cappola, Anne R; Valenti, Giorgio; Ferrucci, Luigi

2009-01-01

To investigate thyroid function testing abnormalities in older persons and to explore the relationship between thyroid dysfunction and cognition. Cross-sectional. Community-based. One thousand one hundred seventy-one men and women aged 23 to 102. Thyroid function was evaluated by measuring plasma concentrations of thyrotropin (TSH), free thyroxine (FT4), and free triiodothyronine (FT3). Cognition was evaluated using the Mini-Mental State Examination (MMSE). Prevalence of overt and subclinical thyroid dysfunction was evaluated in different age groups (<65 vs > or =65). Age trends in TSH, FT4, and FT3 were examined in euthyroid participants. The cross-sectional association between thyroid dysfunction and MMSE score was evaluated adjusting for confounders. Subclinical hypothyroidism and subclinical hyperthyroidism were more prevalent in older than in younger participants (subclinical hypothyroidism, 3.5% vs 0.4%, P<.03; subclinical hyperthyroidism, 7.8% vs 1.9%, P<.002). In euthyroid participants, TSH and FT3 declined with age, whereas FT4 increased. Older participants with subclinical hyperthyroidism had lower MMSE scores than euthyroid subjects (22.61+/-6.88 vs 24.72+/-4.52, P<.03). In adjusted analyses, participants with subclinical hyperthyroidism were significantly more likely to have cognitive dysfunction (hazard rate=2.26, P=.003). Subtle age-related changes in FT3, FT4, and TSH occur in individuals who remain euthyroid. Subclinical hyperthyroidism is the most prevalent thyroid dysfunction in Italian older persons and is associated with cognitive impairment.

Are we comparing frontotemporal dementia and Alzheimer disease patients with the right measures?

PubMed

Deutsch, Mariel B; Liang, Li-Jung; Jimenez, Elvira E; Mather, Michelle J; Mendez, Mario F

2016-09-01

Clinical research studies of behavioral variant frontotemporal dementia (bvFTD) often use Alzheimer disease (AD) as a comparison group for control of dementia variables, using tests of cognitive function to match the groups. These two dementia syndromes, however, are very different in clinical manifestations, and the comparable severity of these dementias may not be reflected by commonly used cognitive scales such as the Mini-Mental State Examination (MMSE). We evaluated different measures of dementia severity and symptoms among 20 people with bvFTD compared to 24 with early-onset AD. Despite similar ages, disease-duration, education, and cognitive performance on two tests of cognitive function, the MMSE and the Montreal Cognitive Assessment (MoCA), the bvFTD participants, compared to the AD participants, were significantly more impaired on other measures of disease severity, including function (Functional Assessment Questionnaire (FAQ)), neuropsychiatric symptoms (Neuropsychiatric Inventory (NPI)), and global dementia stage (Clinical Dementia Rating Scales (CDRs)). However, when we adjusted for the frontotemporal lobar degeneration-CDR (FTLD-CDR) in the analyses, the two dementia groups were comparable across all measures despite significant differences on the cognitive scales. We found tests of cognitive functions (MMSE and MoCA) to be insufficient measures for ensuring comparability between bvFTD and AD groups. In clinical studies, the FTLD-CDR, which includes additional language and behavior items, may be a better overall way to match bvFTD and AD groups on dementia severity.

Are we comparing frontotemporal dementia and Alzheimer disease patients with the right measures?

PubMed Central

Deutsch, Mariel B.; Liang, Li-Jung; Jimenez, Elvira E.; Mather, Michelle J.; Mendez, Mario F.

2016-01-01

Background Clinical research studies of behavioral variant frontotemporal dementia (bvFTD) often use Alzheimer disease (AD) as a comparison group for control of dementia variables, using tests of cognitive function to match the groups. These two dementia syndromes, however, are very different in clinical manifestations, and the comparable severity of these dementias may not be reflected by commonly used cognitive scales such as the Mini-Mental State Examination (MMSE). Methods We evaluated different measures of dementia severity and symptoms among 20 people with bvFTD compared to 24 with early-onset AD. Results Despite similar ages, disease-duration, education, and cognitive performance on two tests of cognitive function, the MMSE and the Montreal Cognitive Assessment (MoCA), the bvFTD participants, compared to the AD participants, were significantly more impaired on other measures of disease severity, including function (Functional Assessment Questionnaire (FAQ)), neuropsychiatric symptoms (Neuropsychiatric Inventory (NPI)), and global dementia stage (Clinical Dementia Rating Scales (CDRs)). However, when we adjusted for the frontotemporal lobar degeneration-CDR (FTLD-CDR) in the analyses, the two dementia groups were comparable across all measures despite significant differences on the cognitive scales. Conclusion We found tests of cognitive functions (MMSE and MoCA) to be insufficient measures for ensuring comparability between bvFTD and AD groups. In clinical studies, the FTLD-CDR, which includes additional language and behavior items, may be a better overall way to match bvFTD and AD groups on dementia severity. PMID:27079571

Physical strength is associated with Mini-Mental State Examination scores in Spanish institutionalized elderly.

PubMed

Pedrero-Chamizo, Raquel; Albers, Ulrike; Tobaruela, José L; Meléndez, Agustín; Castillo, Manuel J; González-Gross, Marcela

2013-10-01

The present cross-sectional study aimed at assessing muscle strength of hands, the dominant arm and legs in Spanish institutionalized elderly people according to sex, age and cognitive status. A total of 153 elderly subjects (102 females, 51 males, mean age 83.6 ± 6.8 years) living in the region of Madrid were measured for handgrip strength (kg) with a Takei TKK 5101 digital dynamometer (range 5-100 kg, precision 0.1 kg), and arm and leg endurance strength (repetitions) according to the Rikli and Jones tests. Cognitive status was determined with the Mini-Mental State Examination (MMSE). The values for men and women were, respectively: 23.5 ± 7.3 kg and 11.6 ± 4.6 kg (right handgrip), 22.0 ± 7.8 kg and 10.7 ± 4.8 kg (left handgrip), 13 ± 5 and 10 ± 5 repetitions (arm strength), 8 ± 5 and 5 ± 4 repetitions (legs strength), and 21 ± 6 and 17 ± 7 (MMSE score). All parameters were significantly higher for men (P ≤ 0.01), but strength decline with age was less pronounced in women. In all MMSE groups, lower strength was associated with lower cognitive status. Strength values were lower in older subjects in both sexes; this difference was higher in men than in women. Higher strength values were associated with better cognitive status, which was the most influencing variable, even more than sex and age. © 2013 Japan Geriatrics Society.

Effects of head circumference and metabolic syndrome on cognitive decline.

PubMed

Lee, Kang Soo; Eom, Jin-Sup; Cheong, Hae-Kwan; Oh, Byoung Hoon; Hong, Chang Hyung

2010-01-01

Brain volume progressively decreases with an increase in atrophy, and the brain becomes more susceptible to degenerative brain diseases such as Alzheimer's disease. Metabolic syndrome has also been associated with an increased risk of cognitive decline in the elderly. In this study, we aimed to examine the effects of head circumference and metabolic syndrome on cognitive decline. This study was part of a longitudinal study conducted on Koreans aged 60 years or older. We analyzed a final sample of 596 Korean participants with complete baseline and 2-year follow-up data. The cognitive function of the subjects was assessed using the Korean version of the Mini Mental State Examination (MMSE). Head circumference was measured from the glabella to the occipital protuberance using a measuring tape. Metabolic syndrome was defined according to the NCEP-ATP III standards. Central obesity was assessed on the basis of waist-circumference values, in accordance with the World Health Organization Western Pacific Region report on Asians. We used a longitudinal factorial design in which the MMSE score was the dependent variable, and head circumference and metabolic syndrome were considered as factors. After adjusting the results for age, gender, education, height, weight, baseline MMSE, and number of follow-up years, we observed that smaller head circumference and the presence of metabolic syndrome were independently associated with rapid cognitive decline. All these findings suggest that smaller head circumference and the presence of metabolic syndrome have additive effects on cognitive decline. Copyright 2009 S. Karger AG, Basel.

Cognitive Functions and Cognitive Reserve in Relation to Blood Pressure Components in a Population-Based Cohort Aged 53 to 94 Years

PubMed Central

Giordano, Nunzia; Tikhonoff, Valérie; Palatini, Paolo; Bascelli, Anna; Boschetti, Giovanni; De Lazzari, Fabia; Grasselli, Carla; Martini, Bortolo; Caffi, Sandro; Piccoli, Antonio; Mazza, Alberto; Bisiacchi, Patrizia; Casiglia, Edoardo

2012-01-01

In 288 men and women from general population in a cross-sectional survey, all neuropsychological tests were negatively associated with age; memory and executive function were also positively related with education. The hypertensives (HT) were less efficient than the normotensives (NT) in the test of memory with interference at 10 sec (MI-10) (−33%, P = 0.03), clock drawing test (CLOX) (−28%, P < 0.01), and mini-mental state examination (MMSE) (−6%, P = 0.02). Lower MMSE, MI-10, and CLOX were predicted by higher systolic (odds ratio, OR, 0.97, P = 0.02; OR 0.98, P < 0.005; OR 0.95, P < 0.001) and higher pulse blood pressure (BP) (OR 0.97, P = 0.02; OR 0.97, P < 0.01; and 0.95, P < 0.0001). The cognitive reserve index (CRI) was 6% lower in the HT (P = 0.03) and was predicted by higher pulse BP (OR 0.82, P < 0.001). The BP vectors of lower MMSE, MI-10, and CLOX were directed towards higher values of systolic and diastolic BP, that of low CRI towards higher systolic and lower diastolic. The label of hypertension and higher values of systolic or pulse BP are associated to worse memory and executive functions. Higher diastolic BP, although insufficient to impair cognition, strengthens this association. CRI is predicted by higher systolic BP associated to lower diastolic BP. PMID:22548150

Blood Pressure Variability and Cognitive Function Among Older African Americans: Introducing a New Blood Pressure Variability Measure.

PubMed

Tsang, Siny; Sperling, Scott A; Park, Moon Ho; Helenius, Ira M; Williams, Ishan C; Manning, Carol

2017-09-01

Although blood pressure (BP) variability has been reported to be associated with cognitive impairment, whether this relationship affects African Americans has been unclear. We sought correlations between systolic and diastolic BP variability and cognitive function in community-dwelling older African Americans, and introduced a new BP variability measure that can be applied to BP data collected in clinical practice. We assessed cognitive function in 94 cognitively normal older African Americans using the Mini-Mental State Examination (MMSE) and the Computer Assessment of Mild Cognitive Impairment (CAMCI). We used BP measurements taken at the patients' three most recent primary care clinic visits to generate three traditional BP variability indices, range, standard deviation, and coefficient of variation, plus a new index, random slope, which accounts for unequal BP measurement intervals within and across patients. MMSE scores did not correlate with any of the BP variability indices. Patients with greater diastolic BP variability were less accurate on the CAMCI verbal memory and incidental memory tasks. Results were similar across the four BP variability indices. In a sample of cognitively intact older African American adults, BP variability did not correlate with global cognitive function, as measured by the MMSE. However, higher diastolic BP variability correlated with poorer verbal and incidental memory. By accounting for differences in BP measurement intervals, our new BP variability index may help alert primary care physicians to patients at particular risk for cognitive decline.

Network meta-analysis of diagnostic test accuracy studies identifies and ranks the optimal diagnostic tests and thresholds for health care policy and decision-making.

PubMed

Owen, Rhiannon K; Cooper, Nicola J; Quinn, Terence J; Lees, Rosalind; Sutton, Alex J

2018-07-01

Network meta-analyses (NMA) have extensively been used to compare the effectiveness of multiple interventions for health care policy and decision-making. However, methods for evaluating the performance of multiple diagnostic tests are less established. In a decision-making context, we are often interested in comparing and ranking the performance of multiple diagnostic tests, at varying levels of test thresholds, in one simultaneous analysis. Motivated by an example of cognitive impairment diagnosis following stroke, we synthesized data from 13 studies assessing the efficiency of two diagnostic tests: Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA), at two test thresholds: MMSE <25/30 and <27/30, and MoCA <22/30 and <26/30. Using Markov chain Monte Carlo (MCMC) methods, we fitted a bivariate network meta-analysis model incorporating constraints on increasing test threshold, and accounting for the correlations between multiple test accuracy measures from the same study. We developed and successfully fitted a model comparing multiple tests/threshold combinations while imposing threshold constraints. Using this model, we found that MoCA at threshold <26/30 appeared to have the best true positive rate, whereas MMSE at threshold <25/30 appeared to have the best true negative rate. The combined analysis of multiple tests at multiple thresholds allowed for more rigorous comparisons between competing diagnostics tests for decision making. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

The effect of telemedicine on cognitive decline in patients with dementia.

PubMed

Kim, Heeseok; Jhoo, Jin Hyeong; Jang, Jae-Won

2017-01-01

Introduction Telemedicine has the advantage of providing medical resources in rural areas, but few studies have been conducted to investigate its efficacy in dementia care, compared to face-to-face care. This study evaluated the effectiveness of telemedicine in relation to cognitive changes in patients with dementia. Methods We evaluated cognitive changes over time, according to care modality, in 188 patients with dementia who were registered at our university-based dementia clinic. We followed 98 patients using telemedicine services and 90 patients who attended the dementia clinic in person. Patients in the telemedicine group also visited a public health center located in a rural area about 50 km from the dementia clinic. Results Changes in the mean annualized Mini-Mental State Examination (MMSE) score were not significantly different between the telemedicine group and the face-to-face dementia clinic group ( p = 0.291), with changes of 0.60 and 1.03 points, respectively. However, cognitive decline was significantly lower in the telemedicine group for the less severe initial cognitive performance subgroup than more severe cognitive performance subgroup ( p = 0.049), with changes of 0.62 and 1.59 points, respectively. Higher initial Clinical Dementia Rating (CDR) scores, MMSE scores, and age were found to be independent predictive factors of subsequent cognitive changes, as indicated by mean annualized MMSE scores. Discussion These findings suggest that telemedicine may be a useful alternative to face-to-face clinical visits for management of dementia in patients who are located in rural areas.

Error Correction, Control Systems and Fuzzy Logic

NASA Technical Reports Server (NTRS)

Smith, Earl B.

2004-01-01

This paper will be a discussion on dealing with errors. While error correction and communication is important when dealing with spacecraft vehicles, the issue of control system design is also important. There will be certain commands that one wants a motion device to execute. An adequate control system will be necessary to make sure that the instruments and devices will receive the necessary commands. As it will be discussed later, the actual value will not always be equal to the intended or desired value. Hence, an adequate controller will be necessary so that the gap between the two values will be closed.

Analysis of limiting information characteristics of quantum-cryptography protocols

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sych, D V; Grishanin, Boris A; Zadkov, Viktor N

2005-01-31

The problem of increasing the critical error rate of quantum-cryptography protocols by varying a set of letters in a quantum alphabet for space of a fixed dimensionality is studied. Quantum alphabets forming regular polyhedra on the Bloch sphere and the continual alphabet equally including all the quantum states are considered. It is shown that, in the absence of basis reconciliation, a protocol with the tetrahedral alphabet has the highest critical error rate among the protocols considered, while after the basis reconciliation, a protocol with the continual alphabet possesses the highest critical error rate. (quantum optics and quantum computation)

Integrated Data and Control Level Fault Tolerance Techniques for Signal Processing Computer Design

DTIC Science & Technology

1990-09-01

TOLERANCE TECHNIQUES FOR SIGNAL PROCESSING COMPUTER DESIGN G. Robert Redinbo I. INTRODUCTION High-speed signal processing is an important application of...techniques and mathematical approaches will be expanded later to the situation where hardware errors and roundoff and quantization noise affect all...detect errors equal in number to the degree of g(X), the maximum permitted by the Singleton bound [13]. Real cyclic codes, primarily applicable to

A tight Cramér-Rao bound for joint parameter estimation with a pure two-mode squeezed probe

NASA Astrophysics Data System (ADS)

Bradshaw, Mark; Assad, Syed M.; Lam, Ping Koy

2017-08-01

We calculate the Holevo Cramér-Rao bound for estimation of the displacement experienced by one mode of an two-mode squeezed vacuum state with squeezing r and find that it is equal to 4 exp ⁡ (- 2 r). This equals the sum of the mean squared error obtained from a dual homodyne measurement, indicating that the bound is tight and that the dual homodyne measurement is optimal.

Mass predictions from the Garvey-Kelson mass relations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jaenecke, J.; Masson, P.J.

Part A: The transverse Garvey-Kelson mass relation represents a homogeneous third-order partial difference equation. Procedures are described for estimating masses of nuclei with Ngreater than or equal toZ from the most general solution of this difference equation subject to a chi/sup 2/ minimization, using the recent atomic mass adjustment of Wapstra, Audi, and Hoekstra as a boundary condition. A judicious division of the input data in subsets of neutron-rich and proton-rich nuclei had to be introduced to reduce systematic errors in long-range extrapolations. Approximately 5600 mass-excess values for nuclei with 2less than or equal toZless than or equal to103, 4lessmore » than or equal toNless than or equal to157, and Ngreater than or equal toZ (except N = Z odd for A<40) have been calculated. The standard deviation for reproducing the known mass-excess values is sigma/sub m/approx. =103 keV.« less

Quantization error of CCD cameras and their influence on phase calculation in fringe pattern analysis.

PubMed

Skydan, Oleksandr A; Lilley, Francis; Lalor, Michael J; Burton, David R

2003-09-10

We present an investigation into the phase errors that occur in fringe pattern analysis that are caused by quantization effects. When acquisition devices with a limited value of camera bit depth are used, there are a limited number of quantization levels available to record the signal. This may adversely affect the recorded signal and adds a potential source of instrumental error to the measurement system. Quantization effects also determine the accuracy that may be achieved by acquisition devices in a measurement system. We used the Fourier fringe analysis measurement technique. However, the principles can be applied equally well for other phase measuring techniques to yield a phase error distribution that is caused by the camera bit depth.

On the effect of surface emissivity on temperature retrievals. [for meteorology

NASA Technical Reports Server (NTRS)

Kornfield, J.; Susskind, J.

1977-01-01

The paper is concerned with errors in temperature retrieval caused by incorrectly assuming that surface emissivity is equal to unity. An error equation that applies to present-day atmospheric temperature sounders is derived, and the bias errors resulting from various emissivity discrepancies are calculated. A model of downward flux is presented and used to determine the effective downward flux. In the 3.7-micron region of the spectrum, emissivities of 0.6 to 0.9 have been observed over land. At a surface temperature of 290 K, if the true emissivity is 0.6 and unit emissivity is assumed, the error would be approximately 11 C. In the 11-micron region, the maximum deviation of the surface emissivity from unity was 0.05.

Criteria for a catastrophically disabled determination for purposes of enrollment. Final rule.

PubMed

2013-12-03

The Department of Veterans Affairs (VA) is amending its regulation concerning the manner in which VA determines that a veteran is catastrophically disabled for purposes of enrollment in priority group 4 for VA health care. As amended by this rulemaking, the regulation articulates the clinical criteria that identify an individual as catastrophically disabled, instead of using the corresponding International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) and Current Procedural Terminology (CPT[registered trademark]) codes. The revisions ensure that the regulation is not out of date when new versions of those codes are published. The revisions also broaden some of the descriptions for a finding of catastrophic disability. Additionally, the final rule does not rely on the Folstein Mini Mental State Examination (MMSE) as a criterion for determining whether a veteran meets the definition of catastrophically disabled, because we have determined that the MMSE is no longer a necessary clinical assessment tool.

Effects on Cognition of Stereotactic Lesional Surgery For the Treatment of Tremor in Multiple Sclerosis

PubMed Central

Jahanshahi, Marjan; Pieter, Socorro; Alusi, Sundus H.; Jones, Catherine R. G.; Glickman, Scott; Stein, John; Aziz, Tipu; Bain, Peter G.

2008-01-01

Objective: To assess the effect of stereotactic lesional surgery for treatment of tremor in multiple sclerosis on cognition. Methods: Eleven patients (3 males, 8 females) with multiple sclerosis participated in the study. Six subjects comprised the surgical group and five the matched control group. All patients were assessed at baseline and three months using a neuropsychological test battery that included measures of intellectual ability, memory, language, perception and executive function. Results: There were no significant differences between the surgical and control groups and no change from pre to post testing except for a decline in scores on the Mini-Mental State Examination (MMSE), WAIS-R Digit Span and Verbal Fluency in the surgical group. Conclusions: The results indicate that stereotactic lesional surgery does not result in major cognitive impairment in multiple sclerosis. However, the decline in MMSE scores, digit span and verbal fluency require further investigation in a larger sample. PMID:19491469

Development of a cognitive function test using virtual reality technology: examination in healthy participants.

PubMed

Sakai, Hiromi; Nagano, Akinori; Seki, Keiko; Okahashi, Sayaka; Kojima, Maki; Luo, Zhiwei

2018-07-01

We developed a virtual reality test to assess the cognitive function of Japanese people in near-daily-life environment, namely, a virtual shopping test (VST). In this test, participants were asked to execute shopping tasks using touch panel operations in a "virtual shopping mall." We examined differences in VST performances among healthy participants of different ages and correlations between VST and screening tests, such as the Mini-Mental State Examination (MMSE) and Everyday Memory Checklist (EMC). We included 285 healthy participants between 20 and 86 years of age in seven age groups. Therefore, each VST index tended to decrease with advancing age; differences among age groups were significant. Most VST indices had a significantly negative correlation with MMSE and significantly positive correlation with EMC. VST may be useful for assessing general cognitive decline; effects of age must be considered for proper interpretation of the VST scores.

The Influence of Cognitive Status on Elder Food Choice and Meal Service Satisfaction.

PubMed

Crogan, Neva L; Short, Robert; Dupler, Alice E; Heaton, Grace

2015-11-01

This article describes the testing of a new nursing home food delivery system that empowers elders to choose the foods they want to eat and gives them an active voice in menu development. Using a 2-group, repeated measures design, 61 elderly residents from 2 eastern Washington nursing homes were recruited to participate in a 6-month study. Outcome measures included food and meal service satisfaction, body weight, serum prealbumin, and food intake. Serum prealbumin levels and body weight increased post intervention for treatment group residents. Mini-Mental Status Examination (MMSE) scores were not associated with the changes in serum prealbumin, body weight, or food intake. The MMSE scores did not influence the resident's ability to actively participate in the rate the food process or choose the foods they liked and preferred to eat. Cognitive impaired older adults experienced weight gain similarly to higher functioning elderly individuals. © The Author(s) 2012.

Green tea consumption affects cognitive dysfunction in the elderly: a pilot study.

PubMed

Ide, Kazuki; Yamada, Hiroshi; Takuma, Norikata; Park, Mijong; Wakamiya, Noriko; Nakase, Junpei; Ukawa, Yuuichi; Sagesaka, Yuko M

2014-09-29

Green tea is known to have various health benefits for humans. However, the effect of green tea consumption on cognitive dysfunction remains to be clinically verified. We conducted a clinical study to investigate the effects of green tea consumption on cognitive dysfunction. Twelve elderly nursing home residents with cognitive dysfunction (Mini-Mental State Examination Japanese version (MMSE-J) score: <28) participated in the study (2 men, 10 women; mean age, 88 years). The participants consumed green tea powder 2 g/day for 3 months. After three months of green tea consumption, the participants' MMSE-J scores were significantly improved (before, 15.3 ± 7.7; after, 17.0 ± 8.2; p = 0.03). This result suggests that green tea consumption may be effective in improving cognitive function or reducing the progression of cognitive dysfunction; however, long-term large-scale controlled studies are needed to further clarify the effect.

Enhanced intercarrier interference mitigation based on encoded bit-sequence distribution inside optical superchannels

NASA Astrophysics Data System (ADS)

Torres, Jhon James Granada; Soto, Ana María Cárdenas; González, Neil Guerrero

2016-10-01

In the context of gridless optical multicarrier systems, we propose a method for intercarrier interference (ICI) mitigation which allows bit error correction in scenarios of nonspectral flatness between the subcarriers composing the multicarrier system and sub-Nyquist carrier spacing. We propose a hybrid ICI mitigation technique which exploits the advantages of signal equalization at both levels: the physical level for any digital and analog pulse shaping, and the bit-data level and its ability to incorporate advanced correcting codes. The concatenation of these two complementary techniques consists of a nondata-aided equalizer applied to each optical subcarrier, and a hard-decision forward error correction applied to the sequence of bits distributed along the optical subcarriers regardless of prior subchannel quality assessment as performed in orthogonal frequency-division multiplexing modulations for the implementation of the bit-loading technique. The impact of the ICI is systematically evaluated in terms of bit-error-rate as a function of the carrier frequency spacing and the roll-off factor of the digital pulse-shaping filter for a simulated 3×32-Gbaud single-polarization quadrature phase shift keying Nyquist-wavelength division multiplexing system. After the ICI mitigation, a back-to-back error-free decoding was obtained for sub-Nyquist carrier spacings of 28.5 and 30 GHz and roll-off values of 0.1 and 0.4, respectively.

Bandwidth efficient bidirectional 5 Gb/s overlapped-SCM WDM PON with electronic equalization and forward-error correction.

PubMed

Buset, Jonathan M; El-Sahn, Ziad A; Plant, David V

2012-06-18

We demonstrate an improved overlapped-subcarrier multiplexed (O-SCM) WDM PON architecture transmitting over a single feeder using cost sensitive intensity modulation/direct detection transceivers, data re-modulation and simple electronics. Incorporating electronic equalization and Reed-Solomon forward-error correction codes helps to overcome the bandwidth limitation of a remotely seeded reflective semiconductor optical amplifier (RSOA)-based ONU transmitter. The O-SCM architecture yields greater spectral efficiency and higher bit rates than many other SCM techniques while maintaining resilience to upstream impairments. We demonstrate full-duplex 5 Gb/s transmission over 20 km and analyze BER performance as a function of transmitted and received power. The architecture provides flexibility to network operators by relaxing common design constraints and enabling full-duplex operation at BER ∼ 10(-10) over a wide range of OLT launch powers from 3.5 to 8 dBm.

The advanced progress of precoding technology in 5g system

NASA Astrophysics Data System (ADS)

An, Chenyi

2017-09-01

With the development of technology, people began to put forward higher requirements for the mobile system, the emergence of the 5G subvert the track of the development of mobile communication technology. In the research of the core technology of 5G mobile communication, large scale MIMO, and precoding technology is a research hotspot. At present, the research on precoding technology in 5G system analyzes the various methods of linear precoding, the maximum ratio transmission (MRT) precoding algorithm, zero forcing (ZF) precoding algorithm, minimum mean square error (MMSE) precoding algorithm based on maximum signal to leakage and noise ratio (SLNR). Precoding algorithms are analyzed and summarized in detail. At the same time, we also do some research on nonlinear precoding methods, such as dirty paper precoding, THP precoding algorithm and so on. Through these analysis, we can find the advantages and disadvantages of each algorithm, as well as the development trend of each algorithm, grasp the development of the current 5G system precoding technology. Therefore, the research results and data of this paper can be used as reference for the development of precoding technology in 5G system.

Reduced-rank technique for joint channel estimation in TD-SCDMA systems

NASA Astrophysics Data System (ADS)

Kamil Marzook, Ali; Ismail, Alyani; Mohd Ali, Borhanuddin; Sali, Adawati; Khatun, Sabira

2013-02-01

In time division-synchronous code division multiple access systems, increasing the system capacity by exploiting the inserting of the largest number of users in one time slot (TS) requires adding more estimation processes to estimate the joint channel matrix for the whole system. The increase in the number of channel parameters due the increase in the number of users in one TS directly affects the precision of the estimator's performance. This article presents a novel channel estimation with low complexity, which relies on reducing the rank order of the total channel matrix H. The proposed method exploits the rank deficiency of H to reduce the number of parameters that characterise this matrix. The adopted reduced-rank technique is based on truncated singular value decomposition algorithm. The algorithms for reduced-rank joint channel estimation (JCE) are derived and compared against traditional full-rank JCEs: least squares (LS) or Steiner and enhanced (LS or MMSE) algorithms. Simulation results of the normalised mean square error showed the superiority of reduced-rank estimators. In addition, the channel impulse responses founded by reduced-rank estimator for all active users offers considerable performance improvement over the conventional estimator along the channel window length.

A Space-Time Signal Decomposition Algorithm for Downlink MIMO DS-CDMA Receivers

NASA Astrophysics Data System (ADS)

Wang, Yung-Yi; Fang, Wen-Hsien; Chen, Jiunn-Tsair

We propose a dimension reduction algorithm for the receiver of the downlink of direct-sequence code-division multiple access (DS-CDMA) systems in which both the transmitters and the receivers employ antenna arrays of multiple elements. To estimate the high order channel parameters, we develop a layered architecture using dimension-reduced parameter estimation algorithms to estimate the frequency-selective multipath channels. In the proposed architecture, to exploit the space-time geometric characteristics of multipath channels, spatial beamformers and constrained (or unconstrained) temporal filters are adopted for clustered-multipath grouping and path isolation. In conjunction with the multiple access interference (MAI) suppression techniques, the proposed architecture jointly estimates the direction of arrivals, propagation delays, and fading amplitudes of the downlink fading multipaths. With the outputs of the proposed architecture, the signals of interest can then be naturally detected by using path-wise maximum ratio combining. Compared to the traditional techniques, such as the Joint-Angle-and-Delay-Estimation (JADE) algorithm for DOA-delay joint estimation and the space-time minimum mean square error (ST-MMSE) algorithm for signal detection, computer simulations show that the proposed algorithm substantially mitigate the computational complexity at the expense of only slight performance degradation.

A Framework of Covariance Projection on Constraint Manifold for Data Fusion.

PubMed

Bakr, Muhammad Abu; Lee, Sukhan

2018-05-17

A general framework of data fusion is presented based on projecting the probability distribution of true states and measurements around the predicted states and actual measurements onto the constraint manifold. The constraint manifold represents the constraints to be satisfied among true states and measurements, which is defined in the extended space with all the redundant sources of data such as state predictions and measurements considered as independent variables. By the general framework, we mean that it is able to fuse any correlated data sources while directly incorporating constraints and identifying inconsistent data without any prior information. The proposed method, referred to here as the Covariance Projection (CP) method, provides an unbiased and optimal solution in the sense of minimum mean square error (MMSE), if the projection is based on the minimum weighted distance on the constraint manifold. The proposed method not only offers a generalization of the conventional formula for handling constraints and data inconsistency, but also provides a new insight into data fusion in terms of a geometric-algebraic point of view. Simulation results are provided to show the effectiveness of the proposed method in handling constraints and data inconsistency.

Uplink transmit beamforming design for SINR maximization with full multiuser channel state information

NASA Astrophysics Data System (ADS)

Xi, Songnan; Zoltowski, Michael D.

2008-04-01

Multiuser multiple-input multiple-output (MIMO) systems are considered in this paper. We continue our research on uplink transmit beamforming design for multiple users under the assumption that the full multiuser channel state information, which is the collection of the channel state information between each of the users and the base station, is known not only to the receiver but also to all the transmitters. We propose an algorithm for designing optimal beamforming weights in terms of maximizing the signal-to-interference-plus-noise ratio (SINR). Through statistical modeling, we decouple the original mathematically intractable optimization problem and achieved a closed-form solution. As in our previous work, the minimum mean-squared error (MMSE) receiver with successive interference cancellation (SIC) is adopted for multiuser detection. The proposed scheme is compared with an existing jointly optimized transceiver design, referred to as the joint transceiver in this paper, and our previously proposed eigen-beamforming algorithm. Simulation results demonstrate that our algorithm, with much less computational burden, accomplishes almost the same performance as the joint transceiver for spatially independent MIMO channel and even better performance for spatially correlated MIMO channels. And it always works better than our previously proposed eigen beamforming algorithm.

Battery Cell By-Pass Circuit

NASA Technical Reports Server (NTRS)

Mumaw, Susan J. (Inventor); Evers, Jeffrey (Inventor); Craig, Calvin L., Jr. (Inventor); Walker, Stuart D. (Inventor)

2001-01-01

The invention is a circuit and method of limiting the charging current voltage from a power supply net work applied to an individual cell of a plurality of cells making up a battery being charged in series. It is particularly designed for use with batteries that can be damaged by overcharging, such as Lithium-ion type batteries. In detail. the method includes the following steps: 1) sensing the actual voltage level of the individual cell; 2) comparing the actual voltage level of the individual cell with a reference value and providing an error signal representative thereof; and 3) by-passing the charging current around individual cell necessary to keep the individual cell voltage level generally equal a specific voltage level while continuing to charge the remaining cells. Preferably this is accomplished by by-passing the charging current around the individual cell if said actual voltage level is above the specific voltage level and allowing the charging current to the individual cell if the actual voltage level is equal or less than the specific voltage level. In the step of bypassing the charging current, the by-passed current is transferred at a proper voltage level to the power supply. The by-pass circuit a voltage comparison circuit is used to compare the actual voltage level of the individual cell with a reference value and to provide an error signal representative thereof. A third circuit, designed to be responsive to the error signal, is provided for maintaining the individual cell voltage level generally equal to the specific voltage level. Circuitry is provided in the third circuit for bypassing charging current around the individual cell if the actual voltage level is above the specific voltage level and transfers the excess charging current to the power supply net work. The circuitry also allows charging of the individual cell if the actual voltage level is equal or less than the specific voltage level.

Global distortion of GPS networks associated with satellite antenna model errors

NASA Astrophysics Data System (ADS)

Cardellach, E.; Elósegui, P.; Davis, J. L.

2007-07-01

Recent studies of the GPS satellite phase center offsets (PCOs) suggest that these have been in error by ˜1 m. Previous studies had shown that PCO errors are absorbed mainly by parameters representing satellite clock and the radial components of site position. On the basis of the assumption that the radial errors are equal, PCO errors will therefore introduce an error in network scale. However, PCO errors also introduce distortions, or apparent deformations, within the network, primarily in the radial (vertical) component of site position that cannot be corrected via a Helmert transformation. Using numerical simulations to quantify the effects of PCO errors, we found that these PCO errors lead to a vertical network distortion of 6-12 mm per meter of PCO error. The network distortion depends on the minimum elevation angle used in the analysis of the GPS phase observables, becoming larger as the minimum elevation angle increases. The steady evolution of the GPS constellation as new satellites are launched, age, and are decommissioned, leads to the effects of PCO errors varying with time that introduce an apparent global-scale rate change. We demonstrate here that current estimates for PCO errors result in a geographically variable error in the vertical rate at the 1-2 mm yr-1 level, which will impact high-precision crustal deformation studies.

Global Distortion of GPS Networks Associated with Satellite Antenna Model Errors

NASA Technical Reports Server (NTRS)

Cardellach, E.; Elosequi, P.; Davis, J. L.

2007-01-01

Recent studies of the GPS satellite phase center offsets (PCOs) suggest that these have been in error by approx.1 m. Previous studies had shown that PCO errors are absorbed mainly by parameters representing satellite clock and the radial components of site position. On the basis of the assumption that the radial errors are equal, PCO errors will therefore introduce an error in network scale. However, PCO errors also introduce distortions, or apparent deformations, within the network, primarily in the radial (vertical) component of site position that cannot be corrected via a Helmert transformation. Using numerical simulations to quantify the effects of PC0 errors, we found that these PCO errors lead to a vertical network distortion of 6-12 mm per meter of PCO error. The network distortion depends on the minimum elevation angle used in the analysis of the GPS phase observables, becoming larger as the minimum elevation angle increases. The steady evolution of the GPS constellation as new satellites are launched, age, and are decommissioned, leads to the effects of PCO errors varying with time that introduce an apparent global-scale rate change. We demonstrate here that current estimates for PCO errors result in a geographically variable error in the vertical rate at the 1-2 mm/yr level, which will impact high-precision crustal deformation studies.

The association of different types of cerebral infarction with post-stroke depression and cognitive impairment.

PubMed

Tu, Jun; Wang, Ling-Xiao; Wen, Hong-Feng; Xu, Yi-Cheng; Wang, Pei-Fu

2018-06-01

The aim of this study was to investigate post-stroke depression (PSD) and cognitive impairments in patients with different types of cerebral infarction.A total of 110 patients with cerebral infarction treated in our hospital from January 2015 to February 2016 were included in present study. Forty-seven patients were PSD patients and 63 patients were non-PSD patients. The Hamilton Depression Rating Scale (HAMD) and Mini-Mental State Examination (MMSE) were employed to assess depression and cognition of patientsAmong PSD patients, the proportion of patients with partial anterior circulation infarction (PACI, 68.75%) was significantly higher than patients with lacunar circulation infarction (LACI, 29.17%) and posterior circulation infarction (POCI, 26.67%) (P < .05). No significant difference was found in PSD patients with LACI and POCI (P > .05). The MMSE score of patients with PACI (18.05 ± 2.61) was lower than patients with POCI and LACI (P < .05), however, no significant difference was found in patients with LACI and POCI (P > 0.05). The incidences of cognitive impairment in patients with PACI, LACI, and POCI were 12.50%, 14.58%, and 13.33%, respectively. The MMSE score of PSD patients (21.23 ± 2.12) was significantly lower than non-PSD patients (P < .05).Compared with LACI and POCI patients, PACI patients had a higher incidence of PSD and impaired cognitive functions. In addition, affective disorders such as depression may be correlated with cognitive impairment in patients with cerebral infarction.

Short-Term Impact of a Combined Nutraceutical on Cognitive Function, Perceived Stress and Depression in Young Elderly with Cognitive Impairment: A Pilot, Double-Blind, Randomized Clinical Trial.

PubMed

Cicero, A F; Bove, M; Colletti, A; Rizzo, M; Fogacci, F; Giovannini, M; Borghi, C

2017-01-01

The prevalence of senile dementia is increasing worldwide, especially in the developed countries. Nevertheless, drug therapy isn't often enough to treat this condition. Researchers are evaluating the possible impact of a preventive approach, based on an improvement of lifestyle and the intake of micronutrients. Moreover, there is an increasing interest for combined nutraceuticals that can act as memory and learning enhancers, with a significant and beneficial potential on the cognitive disorders. To evaluate the effects of a rational assemblage of nutraceuticals on cognitive functions in a sample of 30 elderly subjects. Double bind, cross-over designed trial versus placebo Setting: outpatient clinical practice. 30 elderly subjects with basal Mini-Mental State Examination score between 20 and 27 and self-perceived cognitive decline. Treatment with a combination of nutraceuticals based on Bacopa monnieri, L-theanine, Crocus sativus, copper, folate and vitamins of B and D group. After2 months of treatment or placebo. Patients were evaluated with Mini-Mental State Examination (MMSE), Perceived Stress Questionnaire (PSQ) and Index and Self-Rating Depression Scale (SRDS). MMSE and PSQ Index significantly improved in the active treatment arm, both versus baseline and versus the parallel arm. Both groups experienced a significant improving in the SRDS scores. We obtained a good and significant improvement of the cognitive functions tested with the MMSE, PSQ-Index and SRDS score, after 2 months of combined therapy of nutraceuticals. Further confirmation will be needed to verify these observations on the middle and long term in a larger number of subjects.

Three-Dimensional Gray Matter Atrophy Mapping in Mild Cognitive Impairment and Mild Alzheimer Disease

PubMed Central

Apostolova, Liana G.; Steiner, Calen A.; Akopyan, Gohar G.; Dutton, Rebecca A.; Hayashi, Kiralee M.; Toga, Arthur W.; Cummings, Jeffrey L.; Thompson, Paul M.

2011-01-01

Background Alzheimer disease (AD) is the most common form of dementia worldwide. Mild cognitive impairment (MCI) is the recent terminology for patients with cognitive deficiencies in the absence of functional decline. Most patients with MCI harbor the pathologic changes of AD and demonstrate transition to dementia at a rate of 10% to 15% per year. Patients with AD and MCI experience progressive brain atrophy. Objective To analyze the structural magnetic resonance imaging data for 24 patients with amnestic MCI and 25 patients with mild AD using an advanced 3-dimensional cortical mapping technique. Design Cross-sectional cohort design. Patients/Methods We analyzed the structural magnetic resonance imaging data of 24 amnestic MCI (mean MMSE, 28.1; SD, 1.7) and 25 mild AD patients (all MMSE scores, >18; mean MMSE, 23.7; SD, 2.9) using an advanced 3-dimensional cortical mapping technique. Results We observed significantly greater cortical atrophy in patients with mild AD. The entorhinal cortex, right more than left lateral temporal cortex, right parietal cortex, and bilateral precuneus showed 15% more atrophy and the remainder of the cortex primarily exhibited 10% to 15% more atrophy in patients with mild AD than in patients with amnestic MCI. Conclusion There are striking cortical differences between mild AD and the immediately preceding cognitive state of amnestic MCI. Cortical areas affected earlier in the disease process are more severely affected than those that are affected late. Our method may prove to be a reliable in vivo disease-tracking technique that can also be used for evaluating disease-modifying therapies in the future. PMID:17923632

Food insecurity and cognitive function in Puerto Rican adults.

PubMed

Gao, Xiang; Scott, Tammy; Falcon, Luis M; Wilde, Parke E; Tucker, Katherine L

2009-04-01

Food insecurity is associated with nutrient inadequacy and a variety of unfavorable health outcomes. However, little is known about whether food security is associated with lower cognitive function in the elderly. We investigated the prevalence of food insecurity in a representative sample of 1358 Puerto Ricans aged 45-75 y living in Massachusetts in relation to cognitive function performances. Food security was assessed with the US Household Food Security Scale. Cognitive function was measured to capture general cognition with a battery of 7 tests: Mini-Mental State Examination (MMSE), word list learning (verbal memory), digit span (attention), clock drawing and figure copying (visual-spatial ability), and Stroop and verbal fluency tests (fluency executive functioning). The overall prevalence of food insecurity during the past 12 mo was 12.1%; 6.1% of the subjects reported very low food security. Food insecurity was inversely associated with global cognitive performance, as assessed by the MMSE score. The adjusted difference in the MMSE score was -0.90 (95% CI: -1.6, -0.19; P for trend = 0.003) for a comparison of participants with very low food security with those who were food secure, after adjustment for age, smoking, education, poverty status, income, acculturation, plasma homocysteine, alcohol, diabetes, and hypertension. Food insecurity was significantly associated with lower scores for word-list learning, percentage retention, letter fluency, and digit span backward tests. Very low food security was prevalent among the study subjects and was associated with lower cognitive performance. Further studies, both observational and experimental, are warranted to clarify the direction of causality in this association.

The qualitative scoring MMSE pentagon test (QSPT): a new method for differentiating dementia with Lewy Body from Alzheimer's disease.

PubMed

Caffarra, Paolo; Gardini, Simona; Dieci, Francesca; Copelli, Sandra; Maset, Laura; Concari, Letizia; Farina, Elisabetta; Grossi, Enzo

2013-01-01

The differential diagnosis across different variants of degenerative diseases is sometimes controversial. This study aimed to validate a qualitative scoring method for the pentagons copy test (QSPT) of Mini-Mental State Examination (MMSE) based on the assessment of different parameters of the pentagons drawing, such as number of angles, distance/intersection, closure/opening, rotation, closing-in, and to verify its efficacy to differentiate dementia with Lewy Body (DLB) from Alzheimer's disease (AD). We established the reliability of the qualitative scoring method through the inter-raters and intra-subjects analysis. QSPT was then applied to forty-six AD and forty-six DLB patients, using two phases statistical approach, standard and artificial neural network respectively. DLB patients had significant lower total score in the copy of pentagons and number of angles, distance/intersection, closure/opening, rotation compared to AD. However the logistic regression did not allow to establish any suitable modeling, whereas using Auto-Contractive Map (Auto-CM) the DLB was more strongly associated with low scores in some qualitative parameters of pentagon copying, i.e. number of angles and opening/closure and, for the remaining subitems of the MMSE, in naming, repetition and written comprehension, and for demographic variables of gender (male) and education (6-13 years). Twist system modeling showed that the QSPT had a good sensitivity (70.29%) and specificity (78.67%) (ROC-AUC 0.74). The proposed qualitative method of assessment of pentagons copying used in combination with non-linear analysis, showed to be consistent and effective in the differential diagnosis between Lewy Body and Alzheimer's dementia.

[Usefulness of the 10 pictures reminding test for memory assessment for the diagnosis of Alzheimer's disease, mild cognitive impairment and anxiety/depression].

PubMed

Federico, D; Thomas-Anterion, C; Borg, C; Foyatier Michel, N; Dirson, S; Laurent, B

2008-10-01

Episodic memory is often considered to be essential in the neuropsychological examination of elderly people consulting in the memory clinics. Therefore, the performance of three different episodic memory tests were compared in Alzheimer's disease (AD), mild cognitive impairment (MCI) and anxiety/depression. Seventy-six patients with AD, 46 with MCI, and 36 with anxiety/depression performed three memory tests: (1) three-words immediate and delayed recall of the MMSE test; (2) 10-pictures reminding test; (3) 16-items free and cued reminding test. Patients with AD and MCI differed from the depressed/anxious participants on all subcomponents of the memory tests. Only the three-words immediate and delayed recall in the MMSE test as well as the immediate recall (encoding) of the free and cued reminding test (16-items) did not differ between AD and MCI. Significant correlations were also evidenced between the free and cued recall of the 10 pictures and the score of the 16-items for all patients. Scores of total and free recalls distinguished the three group of patients; also, a trend was observed for the free recall between the patients with AD and MCI. The three-words immediate and delayed recall of the MMSE test is linked with hippocampic dysfunction. Also, the present study suggests that the 10-pictures reminding test, is a simple and reliable test for investigating memory, in addition to other evaluation tests. Finally, further studies would be necessary to assess the sensitivity and specificity of the tests.

Trait Neuroticism, Depression, and Cognitive Function in Older Primary Care Patients

PubMed Central

Boyle, Lisa L.; Lyness, Jeffrey M.; Duberstein, Paul R.; Karuza, Jurgis; King, Deborah A.; Messing, Susan; Tu, Xin

2010-01-01

Objective Prior studies on the association of trait neuroticism and cognitive function in older adults have yielded mixed findings. We tested hypotheses that neuroticism is associated with measures of cognition and that depression moderates these relationships. Design Cross-sectional observational study. Setting Primary care offices. Participants Primary care patients age ≥65 years. Measurements Trait neuroticism was assessed by the NEO-Five Factor Inventory. Major and minor depression (MDD, MinD) were determined by the Structured Clinical Interview for DSM-IV, and depressive symptom severity by the Hamilton Depression Rating Scale (Ham-D). Cognitive measures included the Mini-Mental State Examination (MMSE), Initiation-Perseveration subscale of the Mattis Dementia Rating Scale, and Trail-Making Tests A and B. Results In multiple regression analyses, neuroticism was associated with MMSE score independent of depression diagnosis (β = −0.04, χ2 = 14.2, df = 1, p = 0.0002, 95% CI = −0.07, −0.02) and Ham-D score (β = −0.04, χ2 = 8.97, df = 1, p = 0.003, 95% CI = −0.06, −0.01). Interactions between neuroticism and depression diagnosis (χ2 = 7.21, df = 2, p = 0.03) and Ham-D scores (χ2 = 0.55, df = 1, p = 0.46) failed to lend strong support to the moderation hypothesis. Conclusion Neuroticism is associated with lower MMSE scores. Findings do not confirm a moderating role for depression, but suggest that depression diagnosis may confer additional risk for poorer global cognitive function in patients with high neuroticism. Further study is necessary. PMID:20220585

Thyroid Function Abnormalities and Cognitive Impairment in the Elderly. Results of the InCHIANTI Study

PubMed Central

Ceresini, Graziano; Lauretani, Fulvio; Maggio, Marcello; Ceda, Gian Paolo; Morganti, Simonetta; Usberti, Elisa; Chezzi, Carlo; Valcavi, Rita; Bandinelli, Stefania; Guralnik, Jack M.; Cappola, Anne R.; Valenti, Giorgio; Ferrucci, Luigi

2008-01-01

Objectives To investigate thyroid function testing abnormalities in older persons and to explore the relationship between thyroid dysfunction and cognition. Design Cross-sectional study Setting Community-based Participants 1171 men and women aged 23-102 yrs Measurements Thyroid function was evaluated by measuring plasma concentrations of thyrotropin (TSH), free thyroxine (FT4), and free triiodothyronine (FT3). Cognition was evaluated by the Mini Mental State Examination (MMSE). Prevalence of overt and subclinical thyroid dysfunction was evaluated in different age groups (<65 versus ≥65 years). Age trends in TSH, FT4, and FT3 were examined in euthyroid participants. The cross-sectional association of thyroid dysfunction with MMSE score was evaluated adjusting for confounders. Results Both subclinical hypothyroidism and subclinical hyperthyroidism were more prevalent in older than in younger participants (Subclinical hypothyroidism, 0.4 % vs 3.5 % in younger vs older participants, respectively, P<.03 Subclinical hyperthyroidism, 1.9 % vs 7.8 % in younger vs older participants, respectively, P<.002). In euthyroid participants TSH and FT3 declined with age while FT4 increased. Old participants with subclinical hyperthyroidism had a lower MMSE score than euthyroid subjects (22.61 ± 6.88 vs 24.72 ± 4.52, P<.03). In adjusted analyses, participants with subclinical hyperthyroidism were significantly more likely to have cognitive dysfunction (HR: 2.26, P= .003). Conclusion Subtle age-related changes in FT3, FT4 and TSH occur in individuals who remain euthyroid. Subclinical hyperthyroidism is the most prevalent thyroid dysfunction in Italian older persons and is associated with cognitive impairment. PMID:19054181

Factors affecting unplanned readmissions from community hospitals to acute hospitals: a prospective observational study.

PubMed

Leong, Ian Y O; Chan, Siew-Pang; Tan, Boon-Yeow; Sitoh, Yih-Yiow; Ang, Yan-Hoon; Merchant, Reshma; Kanagasabai, Kala; Lee, Patricia S Y; Pang, Weng-Sun

2009-02-01

While the readmission rate from community hospitals is known, the factors affecting it are not. Our aim was to determine the factors predicting unplanned readmissions from community hospitals (CHs) to acute hospitals (AHs). This was an observational prospective cohort study, involving 842 patients requiring post-acute rehabilitation in 2 CHs admitted from 3 AHs in Singapore. We studied the role of the Cumulative Illness Rating Scale (CIRS) organ impairment scores, the Mini-mental State Examination (MMSE) score, the Shah modified Barthel Index (BI) score, and the triceps skin fold thickness (TSFT) in predicting the rate of unplanned readmissions (UR), early unplanned readmissions (EUPR) and late unplanned readmissions (LUPR). We developed a clinical prediction rule to determine the risk of UR and EUPR. The rates of EUPR and LUPR were 7.6% and 10.3% respectively. The factors that predicted UR were the CIRS-heart score, the CIRS-haemopoietic score, the CIRS-endocrine / metabolic score and the BI on admission. The MMSE was predictive of EUPR. The TSFT and CIRS-liver score were predictive of LUPR. Upon receiver operator characteristics analysis, the clinical prediction rules for the prediction of EUPR and UR had areas under the curve of 0.745 and 0.733 respectively. The likelihood ratios of the clinical prediction rules for EUPR and UR ranged from 0.42 to 5.69 and 0.34 to 3.16 respectively. Patients who have UR can be identified by the admission BI, the MMSE, the TSFT and CIRS scores in the cardiac, haemopoietic, liver and endocrine/metabolic systems.

Influence of dual task and frailty on gait parameters of older community-dwelling individuals

PubMed Central

Guedes, Rita C.; Dias, Rosângela C.; Pereira, Leani S. M.; Silva, Sílvia L. A.; Lustosa, Lygia P.; Dias, João M. D.

2014-01-01

Background: Gait parameters such as gait speed (GS) are important indicators of functional capacity. Frailty Syndrome is closely related to GS and is also capable of predicting adverse outcomes. The cognitive demand of gait control is usually explored with dual-task (DT) methodology. Objective: To investigate the effect of DT and frailty on the spatio-temporal parameters of gait in older people and identify which variables relate to GS. Method: The presence of frailty was verified by Fried's Frailty Criteria. Cognitive function was evaluated with the Mini-Mental State Exam (MMSE) and gait parameters were analyzed through the GAITRite(r) system in the single-task and DT conditions. The Kolmogorov-Smirnov, ANOVA, and Pearson's Correlation tests were administered. Results: The participants were assigned to the groups frail (FG), pre-frail (PFG), and non-frail (NFG). During the DT, the three groups showed a decrease in GS, cadence, and stride length and an increase in stride time (p<0.001). The reduction in the GS of the FG during the DT showed a positive correlation with the MMSE scores (r=730; p=0.001) and with grip strength (r=681; p=0.001). Conclusions: Gait parameters are more affected by the DT, especially in the frail older subjects. The reduction in GS in the FG is associated with lower grip strength and lower scores in the MMSE. The GS was able to discriminate the older adults in the three levels of frailty, being an important measure of the functional capacity in this population. PMID:25372007

Cognitive function affects trainability for physical performance in exercise intervention among older adults with mild cognitive impairment.

PubMed

Uemura, Kazuki; Shimada, Hiroyuki; Makizako, Hyuma; Doi, Takehiko; Yoshida, Daisuke; Tsutsumimoto, Kota; Anan, Yuya; Suzuki, Takao

2013-01-01

Although much evidence supports the hypothesis that cognitive function and physical function are interrelated, it is unclear whether cognitive decline with mild cognitive impairment influences trainability of physical performance in exercise intervention. The purpose of this study was to examine the association between cognitive function at baseline and change in physical performance after exercise intervention in older adults with mild cognitive impairment. Forty-four older adults diagnosed with mild cognitive impairment based on the Peterson criteria (mean age 74.8 years) consented to and completed a 6-month twice weekly exercise intervention. The Timed Up and Go (TUG) test was used as a measure of physical performance. The Mini-Mental State Examination (MMSE), Trail Making Test Part B, Geriatric Depression Scale, baseline muscle strength of knee extension, and attendance rate of intervention, were measured as factors for predicting trainability. In the correlation analysis, the change in TUG showed modest correlations with attendance rate in the exercise program (r = -0.354, P = 0.027) and MMSE at baseline (r = -0.321, P = 0.034). A multiple regression analysis revealed that change in TUG was independently associated with attendance rate (β = -0.322, P = 0.026) and MMSE score (β = -0.295, P = 0.041), controlling for age and gender. General cognitive function was associated with improvements in physical performance after exercise intervention in subjects with mild cognitive impairment. Further research is needed to examine the effects of exercise programs designed to address cognitive obstacles in older adults with mild cognitive impairment.

Psychological functioning and adherence to the recommended dose of physical activity in later life: results from a national health survey.

PubMed

Netz, Yael; Dunsky, Ayelet; Zach, Sima; Goldsmith, Rebecca; Shimony, Tal; Goldbourt, Uri; Zeev, Aviva

2012-12-01

Official health organizations have established the dose of physical activity needed for preserving both physical and psychological health in old age. The objective of this study was to explore whether adherence to the recommended criterion of physical activity accounted for better psychological functioning in older adults in Israel. A random sample of 1,663 (799 men) Israelis reported their physical activity routine, and based on official guidelines were divided into sufficiently active, insufficiently active, and inactive groups. The General Health Questionnaire (GHQ) was used for assessing mental health and the Mini-Mental State Examination (MMSE) for assessing cognitive functioning. Factor analysis performed on the GHQ yielded two factors - positive and negative. Logistic regressions for the GHQ factors and for the MMSE were conducted for explaining their variance, with demographic variables entered first, followed by health and then physical activity. The explained variance in the three steps was Cox and Snell R2 = 0.022, 0.023, 0.039 for the positive factor, 0.066, 0.093, 0.101 for the negative factor, and 0.204, 0.206, 0.209 for the MMSE. Adherence to the recommended dose of physical activity accounted for better psychological functioning beyond demographic and health variables; however, the additional explained variance was small. More specific guidelines of physical activity may elucidate a stronger relationship, but only randomized controlled trials can reveal cause-effect relationship between physical activity and psychological functioning. More studies are needed focusing on the positive factor of psychological functioning.

Dietary Vitamin K Intake Is Associated with Cognition and Behaviour among Geriatric Patients: The CLIP Study.

PubMed

Chouet, Justine; Ferland, Guylaine; Féart, Catherine; Rolland, Yves; Presse, Nancy; Boucher, Kariane; Barberger-Gateau, Pascale; Beauchet, Olivier; Annweiler, Cedric

2015-08-12

Our objective was to determine whether dietary vitamin K intake was associated with cognition and behavior among older adults. 192 consecutive participants ≥65 years, recruited in the cross-sectional CLIP (Cognition and LIPophilic vitamins) study, were separated into two groups according to the tertiles of dietary phylloquinone intake (i.e., lowest third below 207 µg/day versus the other two thirds combined). Daily dietary phylloquinone intake was estimated from 50-item interviewer-administered food frequency questionnaire. Cognition was assessed with Mini-Mental State Examination (MMSE); behaviour with Frontotemporal Behavioral Rating Scale (FBRS). Age, gender, social problems, education, body mass index (BMI), comorbidities, history of stroke, use vitamin K antagonists, inadequate fatty fish intake, serum thyroid-stimulating hormone (TSH), vitamin B12, albumin, and estimated glomerular filtration rate were used as confounders. Compared to participants in the lowest third of dietary phylloquinone intake (n = 64), those with higher intake had higher (i.e., better) mean MMSE score (22.0 ± 5.7 versus 19.9 ± 6.2, p = 0.024) and lower (i.e., better) FBRS score (1.5 ± 1.2 versus 1.9 ± 1.3, p = 0.042). In multivariate linear regressions, log dietary phylloquinone intake was positively associated with MMSE score (adjusted β = 1.66, p = 0.013) and inversely associated with FBRS score (adjusted β = -0.33, p = 0.037). Specifically, log dietary phylloquinone intake correlated negatively with FBRS subscore of physical neglect (r = -0.24, p = 0.001). Higher dietary phylloquinone intake was associated with better cognition and behavior among older adults.

Preliminary data on a mnemonic instrument with proverbs for tracking Alzheimer's disease.

PubMed

Santos, Mauricéa Tabósa Ferreira; Guerra, Gutemberg; de Menezes, Terce Liana; Carvalho, Tatiana Lins; Alchieri, João Carlos; Sougey, Everton Botelho

2008-01-01

In the differential diagnosis between Alzheimer's disease (AD) and normal aging, tests evaluating memory and executive functions are frequently used. The addition of abstraction tests may enhance the effectiveness of screening tests for AD. The aim of this study was to compare initial data of a new instrument - The Screening Test for Alzheimer's Disease with Proverbs (STADP) - against other screening tests used in AD diagnosis. Sixty elderly individuals (46 controls and 14 AD subjects with CDR=1), aged =60 years, with at least one year of schooling, were evaluated using the STADP at outpatient clinic. The STADP assesses short-term memory, episodic memory, executive functions and language, in addition to proverb recognition. The performance of the participants on the Mini-Mental State Examination (MMSE), semantic Verbal Fluency (VF) and Clock Drawing Test (CDT) were evaluated and the habit of reading, writing and sociodemographic data were also taken into account. There were significant correlations between STADP and the performance on the MMSE (r=0.64), CDT (r=0.50) and VF (r=0.56). Age influenced all sub-items of the STADP, specifically episodic memory (r= -0.54), whereas schooling mainly influenced executive functions and language (r=0.46). The total score, stages A and C and the "proverb recognition" of STADP (p<0.001), as well as the MMSE (p<0.001), CDT (p=0.016), VF (p<0.001) were significantly different in AD versus control groups. The findings point to the potential use of the STADP in AD, warranting the conducting of further studies.

Movement velocity in the chair squat is associated with measures of functional capacity and cognition in elderly people at low risk of fall.

PubMed

Balsalobre-Fernández, Carlos; Cordón, Ángel; Unquiles, Nazaret; Muñoz-García, Daniel

2018-01-01

The purpose of this study was to analyze the relationships between muscular performance consisting of a single repetition on the chair squat exercise (CSQ) and different measures of functional capacity, balance, quality of life and cognitive status in older adults. A total of 40 participants (22 women, 18 men; age = 72.2 ± 4.9 years) joined the investigation. Muscular performance was assessed by measuring movement velocity in the CSQ with no external load using a validated smartphone application ( PowerLift for iOS). Functional capacity, balance, quality of life and cognitive status were evaluated using the hand-grip strength (HGS) test, the Berg-scale, the EuroQol 5D (EQ-5D) and the Mini mental state examination questionnaire (MMSE). Finally, participants were divided into two subgroups ( N = 20) according to their velocity in the CSQ exercise. Positive correlations were obtained between movement velocity in the CSQ and HGS ( r = 0.76, p < 0.001), the Berg-scale ( r = 0.65, p < 0.001), the EQ-5D ( r = 0.34, p = 0.03) and the MMSE ( r = 0.36, p = 0.02). Participants in the fastest subgroup showed very likely higher scores in the Berg-scale (ES = 1.15) and the HGS (ES = 1.79), as well as likely higher scores in the MMSE scale (ES = 0.69). These results could have potential clinical relevance as they support the use of a time-efficient, non-fatiguing test of muscular performance (i.e., the CSQ) to evaluate functional capacity and mental cognition in older adults.

Effects of Bisphosphonates and Calcium plus Vitamin-D Supplements on Cognitive Function in Postmenopausal Osteoporosis§.

PubMed

Safer, Umut; Safer, Vildan Binay; Demir, Sibel Ozbudak; Yanikoglu, Inci

2016-01-01

Postmenopausal osteoporosis has been linked to accelerated cognitive decline; however, little is known about the effects of medical treatment on cognitive functions. In this prospective study, we evaluated the effects of bisphosphonate treatment and calcium plus vitamin D supplementation on cognitive functions in 45 women with postmenopausal osteoporosis who were started on medical treatment. The medications included alendronate, zoledronic acid, risedronate, or ibandronic acid along with a low or high dose of calcium plus vitamin D supplements. The cognitive function was assessed by the mini-mental state examination (MMSE) test. All subjects underwent bone mineral density (BMD) measurement via dual-energy X-ray absorptiometry at baseline and at study completion. The mean T-score improved significantly at 1 year, except for neck of the femur area. The mean MMSE score did not change significantly at 12 months (26.40 ± 2.07 vs. 26.48 ± 2.07; p = 0.513), with no difference among bisphosphonates combined with calcium plus vitamin D. Higher dose (1200 mg/800 U/day) of calcium plus vitamin D supplementation tended to have a greater improvement as compared with lower dose (600 mg/400 U/day) (Δ MMSE: 0.11 ± 0.72 vs. -0.14 ± 0.69). Cognitive functions in the women remained unaltered, whereas bone BMD T-scores were significantly improved at the 12(th) month after the administration of bisphosphonates and calcium plus vitamin D supplements. Higher doses of calcium plus vitamin D supplements were likely to have better cognitive effects as compared with lower doses.

Clinical Significance of Cerebrovascular Biomarkers and White Matter Tract Integrity in Alzheimer Disease: Clinical correlations With Neurobehavioral Data in Cross-Sectional and After 18 Months Follow-ups.

PubMed

Wu, Ming-Kung; Lu, Yan-Ting; Huang, Chi-Wei; Lin, Pin-Hsuan; Chen, Nai-Ching; Lui, Chun-Chung; Chang, Wen-Neng; Lee, Chen-Chang; Chang, Ya-Ting; Chen, Sz-Fan; Chang, Chiung-Chih

2015-07-01

Cerebrovascular risk factors and white matter (WM) damage lead to worse cognitive performance in Alzheimer dementia (AD). This study investigated WM microstructure using diffusion tensor imaging in patients with mild to moderate AD and investigated specific fiber tract involvement with respect to predefined cerebrovascular risk factors and neurobehavioral data prediction cross-sectionally and after 18 months. To identify the primary pathoanatomic relationships of risk biomarkers to fiber tract integrity, we predefined 11 major association tracts and calculated tract specific fractional anisotropy (FA) values. Eighty-five patients with AD underwent neurobehavioral assessments including the minimental state examination (MMSE) and 12-item neuropsychiatric inventory twice with a 1.5-year interval to represent major outcome factors. In the cross-sectional data, total cholesterol, low-density lipoprotein, vitamin B12, and homocysteine levels correlated variably with WM FA values. After entering the biomarkers and WM FA into a regression model to predict neurobehavioral outcomes, only fiber tract FA or homocysteine level predicted the MMSE score, and fiber tract FA or age predicted the neuropsychiatric inventory total scores and subdomains of apathy, disinhibition, and aberrant motor behavior. In the follow-up neurobehavioral data, the mean global FA value predicted the MMSE and aberrant motor behavior subdomain, while age predicted the anxiety and elation subdomains. Cerebrovascular risk biomarkers may modify WM microstructural organization, while the association with fiber integrity showed greater clinical significance to the prediction of neurobehavioral outcomes both cross-sectionally and longitudinally.

Education and trajectories of cognitive decline over 9 years in very old people: methods and risk analysis.

PubMed

Muniz-Terrera, Graciela; Matthews, Fiona; Dening, Tom; Huppert, Felicia A; Brayne, Carol

2009-05-01

the investigation of cognitive decline in the older population has been hampered by analytical considerations. Most studies of older people over prolonged periods suffer from loss to follow-up, yet this has seldom been investigated fully to date. Such considerations limit our understanding of how basic variables such as education can affect cognitive trajectories. we examined cognitive trajectories in a population-based cohort study in Cambridge, UK, of people aged 75 and over in whom multiple interviews were conducted over time. Cognitive function was assessed using the Mini-Mental State Examination (MMSE). Socio-demographic variables were measured, including educational level and social class. An age-based quadratic latent growth model was fitted to cognitive scores. The effect of socio-demographic variables was examined on all latent variables and the probability of death and dropout. at baseline, age, education, social class and mobility were associated with cognitive performance. Education and social class were not related to decline or its rate of change. In contrast, poor mobility was associated with lower cognitive performance, increased cognitive decline and increased rate of change of cognitive decline. Gender, age, mobility and cognitive ability predicted death and dropout contrary to much of the current literature, education was not related to rate of cognitive decline or change in this rate as measured by MMSE. Higher levels of education do not appear to protect against cognitive decline, though if the MMSE is used in the diagnostic process, individuals with less education may be diagnosed as having dementia somewhat earlier.

Sample size determination in combinatorial chemistry.

PubMed Central

Zhao, P L; Zambias, R; Bolognese, J A; Boulton, D; Chapman, K

1995-01-01

Combinatorial chemistry is gaining wide appeal as a technique for generating molecular diversity. Among the many combinatorial protocols, the split/recombine method is quite popular and particularly efficient at generating large libraries of compounds. In this process, polymer beads are equally divided into a series of pools and each pool is treated with a unique fragment; then the beads are recombined, mixed to uniformity, and redivided equally into a new series of pools for the subsequent couplings. The deviation from the ideal equimolar distribution of the final products is assessed by a special overall relative error, which is shown to be related to the Pearson statistic. Although the split/recombine sampling scheme is quite different from those used in analysis of categorical data, the Pearson statistic is shown to still follow a chi2 distribution. This result allows us to derive the required number of beads such that, with 99% confidence, the overall relative error is controlled to be less than a pregiven tolerable limit L1. In this paper, we also discuss another criterion, which determines the required number of beads so that, with 99% confidence, all individual relative errors are controlled to be less than a pregiven tolerable limit L2 (0 < L2 < 1). PMID:11607586

Aliasing errors in measurements of beam position and ellipticity

NASA Astrophysics Data System (ADS)

Ekdahl, Carl

2005-09-01

Beam position monitors (BPMs) are used in accelerators and ion experiments to measure currents, position, and azimuthal asymmetry. These usually consist of discrete arrays of electromagnetic field detectors, with detectors located at several equally spaced azimuthal positions at the beam tube wall. The discrete nature of these arrays introduces systematic errors into the data, independent of uncertainties resulting from signal noise, lack of recording dynamic range, etc. Computer simulations were used to understand and quantify these aliasing errors. If required, aliasing errors can be significantly reduced by employing more than the usual four detectors in the BPMs. These simulations show that the error in measurements of the centroid position of a large beam is indistinguishable from the error in the position of a filament. The simulations also show that aliasing errors in the measurement of beam ellipticity are very large unless the beam is accurately centered. The simulations were used to quantify the aliasing errors in beam parameter measurements during early experiments on the DARHT-II accelerator, demonstrating that they affected the measurements only slightly, if at all.

Aniseikonia quantification: error rate of rule of thumb estimation.

PubMed

Lubkin, V; Shippman, S; Bennett, G; Meininger, D; Kramer, P; Poppinga, P

1999-01-01

To find the error rate in quantifying aniseikonia by using "Rule of Thumb" estimation in comparison with proven space eikonometry. Study 1: 24 adult pseudophakic individuals were measured for anisometropia, and astigmatic interocular difference. Rule of Thumb quantification for prescription was calculated and compared with aniseikonia measurement by the classical Essilor Projection Space Eikonometer. Study 2: parallel analysis was performed on 62 consecutive phakic patients from our strabismus clinic group. Frequency of error: For Group 1 (24 cases): 5 ( or 21 %) were equal (i.e., 1% or less difference); 16 (or 67% ) were greater (more than 1% different); and 3 (13%) were less by Rule of Thumb calculation in comparison to aniseikonia determined on the Essilor eikonometer. For Group 2 (62 cases): 45 (or 73%) were equal (1% or less); 10 (or 16%) were greater; and 7 (or 11%) were lower in the Rule of Thumb calculations in comparison to Essilor eikonometry. Magnitude of error: In Group 1, in 10/24 (29%) aniseikonia by Rule of Thumb estimation was 100% or more greater than by space eikonometry, and in 6 of those ten by 200% or more. In Group 2, in 4/62 (6%) aniseikonia by Rule of Thumb estimation was 200% or more greater than by space eikonometry. The frequency and magnitude of apparent clinical errors of Rule of Thumb estimation is disturbingly large. This problem is greatly magnified by the time and effort and cost of prescribing and executing an aniseikonic correction for a patient. The higher the refractive error, the greater the anisometropia, and the worse the errors in Rule of Thumb estimation of aniseikonia. Accurate eikonometric methods and devices should be employed in all cases where such measurements can be made. Rule of thumb estimations should be limited to cases where such subjective testing and measurement cannot be performed, as in infants after unilateral cataract surgery.

A comparison of visual and kinesthetic-tactual displays for compensatory tracking

NASA Technical Reports Server (NTRS)

Jagacinski, R. J.; Flach, J. M.; Gilson, R. D.

1983-01-01

Recent research on manual tracking with a kinesthetic-tactual (KT) display suggests that under certain conditions it can be an effective alternative or supplement to visual displays. In order to understand better how KT tracking compares with visual tracking, both a critical tracking and stationary single-axis tracking tasks were conducted with and without velocity quickening. In the critical tracking task, the visual displays were superior, however, the quickened KT display was approximately equal to the unquickened visual display. In stationary tracking tasks, subjects adopted lag equalization with the quickened KT and visual displays, and mean-squared error scores were approximately equal. With the unquickened displays, subjects adopted lag-lead equalization, and the visual displays were superior. This superiority was partly due to the servomotor lag in the implementation of the KT display and partly due to modality differences.

Type I error probabilities based on design-stage strategies with applications to noninferiority trials.

PubMed

Rothmann, Mark

2005-01-01

When testing the equality of means from two different populations, a t-test or large sample normal test tend to be performed. For these tests, when the sample size or design for the second sample is dependent on the results of the first sample, the type I error probability is altered for each specific possibility in the null hypothesis. We will examine the impact on the type I error probabilities for two confidence interval procedures and procedures using test statistics when the design for the second sample or experiment is dependent on the results from the first sample or experiment (or series of experiments). Ways for controlling a desired maximum type I error probability or a desired type I error rate will be discussed. Results are applied to the setting of noninferiority comparisons in active controlled trials where the use of a placebo is unethical.

Dual processing and diagnostic errors.

PubMed

Norman, Geoff

2009-09-01

In this paper, I review evidence from two theories in psychology relevant to diagnosis and diagnostic errors. "Dual Process" theories of thinking, frequently mentioned with respect to diagnostic error, propose that categorization decisions can be made with either a fast, unconscious, contextual process called System 1 or a slow, analytical, conscious, and conceptual process, called System 2. Exemplar theories of categorization propose that many category decisions in everyday life are made by unconscious matching to a particular example in memory, and these remain available and retrievable individually. I then review studies of clinical reasoning based on these theories, and show that the two processes are equally effective; System 1, despite its reliance in idiosyncratic, individual experience, is no more prone to cognitive bias or diagnostic error than System 2. Further, I review evidence that instructions directed at encouraging the clinician to explicitly use both strategies can lead to consistent reduction in error rates.

Follow the Leader Tracking by Autonomous Underwater Vehicles (AUVs) Using Acoustic Communications and Ranging

DTIC Science & Technology

2003-09-01

590-595, September 1996. Deitel , H.M., Deitel , P.J., Nieto, T.R., Lin, T.M., Sadhu, P., XML: How to Program , Prentice Hall, 2001. Du, Y...communications will result in a total track following error equal to the sum of the errors for the two vehicles........48 xv Figure 36. Test point programming ...Refer to (Hunter 2000), ( Deitel 2001), or similar references for additional information regarding the XML standard. Figure 17. XML example

Local projection stabilization for linearized Brinkman-Forchheimer-Darcy equation

NASA Astrophysics Data System (ADS)

Skrzypacz, Piotr

2017-09-01

The Local Projection Stabilization (LPS) is presented for the linearized Brinkman-Forchheimer-Darcy equation with high Reynolds numbers. The considered equation can be used to model porous medium flows in chemical reactors of packed bed type. The detailed finite element analysis is presented for the case of nonconstant porosity. The enriched variant of LPS is based on the equal order interpolation for the velocity and pressure. The optimal error bounds for the velocity and pressure errors are justified numerically.

Adaptive reconfigurable V-BLAST type equalizer for cognitive MIMO-OFDM radios

NASA Astrophysics Data System (ADS)

Ozden, Mehmet Tahir

2015-12-01

An adaptive channel shortening equalizer design for multiple input multiple output-orthogonal frequency division multiplexing (MIMO-OFDM) radio receivers is considered in this presentation. The proposed receiver has desirable features for cognitive and software defined radio implementations. It consists of two sections: MIMO decision feedback equalizer (MIMO-DFE) and adaptive multiple Viterbi detection. In MIMO-DFE section, a complete modified Gram-Schmidt orthogonalization of multichannel input data is accomplished using sequential processing multichannel Givens lattice stages, so that a Vertical Bell Laboratories Layered Space Time (V-BLAST) type MIMO-DFE is realized at the front-end section of the channel shortening equalizer. Matrix operations, a major bottleneck for receiver operations, are accordingly avoided, and only scalar operations are used. A highly modular and regular radio receiver architecture that has a suitable structure for digital signal processing (DSP) chip and field programable gate array (FPGA) implementations, which are important for software defined radio realizations, is achieved. The MIMO-DFE section of the proposed receiver can also be reconfigured for spectrum sensing and positioning functions, which are important tasks for cognitive radio applications. In connection with adaptive multiple Viterbi detection section, a systolic array implementation for each channel is performed so that a receiver architecture with high computational concurrency is attained. The total computational complexity is given in terms of equalizer and desired response filter lengths, alphabet size, and number of antennas. The performance of the proposed receiver is presented for two-channel case by means of mean squared error (MSE) and probability of error evaluations, which are conducted for time-invariant and time-variant channel conditions, orthogonal and nonorthogonal transmissions, and two different modulation schemes.

Attention failures versus misplaced diligence: separating attention lapses from speed-accuracy trade-offs.

PubMed

Seli, Paul; Cheyne, James Allan; Smilek, Daniel

2012-03-01

In two studies of a GO-NOGO task assessing sustained attention, we examined the effects of (1) altering speed-accuracy trade-offs through instructions (emphasizing both speed and accuracy or accuracy only) and (2) auditory alerts distributed throughout the task. Instructions emphasizing accuracy reduced errors and changed the distribution of GO trial RTs. Additionally, correlations between errors and increasing RTs produced a U-function; excessively fast and slow RTs accounted for much of the variance of errors. Contrary to previous reports, alerts increased errors and RT variability. The results suggest that (1) standard instructions for sustained attention tasks, emphasizing speed and accuracy equally, produce errors arising from attempts to conform to the misleading requirement for speed, which become conflated with attention-lapse produced errors and (2) auditory alerts have complex, and sometimes deleterious, effects on attention. We argue that instructions emphasizing accuracy provide a more precise assessment of attention lapses in sustained attention tasks. Copyright © 2011 Elsevier Inc. All rights reserved.

Gating of neural error signals during motor learning

PubMed Central

Kimpo, Rhea R; Rinaldi, Jacob M; Kim, Christina K; Payne, Hannah L; Raymond, Jennifer L

2014-01-01

Cerebellar climbing fiber activity encodes performance errors during many motor learning tasks, but the role of these error signals in learning has been controversial. We compared two motor learning paradigms that elicited equally robust putative error signals in the same climbing fibers: learned increases and decreases in the gain of the vestibulo-ocular reflex (VOR). During VOR-increase training, climbing fiber activity on one trial predicted changes in cerebellar output on the next trial, and optogenetic activation of climbing fibers to mimic their encoding of performance errors was sufficient to implant a motor memory. In contrast, during VOR-decrease training, there was no trial-by-trial correlation between climbing fiber activity and changes in cerebellar output, and climbing fiber activation did not induce VOR-decrease learning. Our data suggest that the ability of climbing fibers to induce plasticity can be dynamically gated in vivo, even under conditions where climbing fibers are robustly activated by performance errors. DOI: http://dx.doi.org/10.7554/eLife.02076.001 PMID:24755290

First-line management of distal humerus fracture by total elbow arthroplasty in geriatric traumatology: Results in a 21-patient series at a minimum 2years' follow-up.

PubMed

Lami, D; Chivot, M; Caubere, A; Galland, A; Argenson, J N

2017-10-01

Total elbow arthroplasty (TEA) is one option in distal humerus fracture in elderly osteoporotic patients. The study hypothesis was that, in patients aged 70years or more, TEA provides functional results and ranges of motion compatible with everyday activity, with a complications rate equal to or lower than with internal fixation, and no loss of autonomy or cognitive impairment. In this retrospective study, 21 patients receiving TEA for distal humerus fracture were included. Mean follow-up was 3.2years, with functional (Quick DASH and MEPS), cognitive (MMSE), autonomy-related (ADL) and radiological assessment (Morrey). Mean MEPS was 84 and QuickDASH 32.4. Mean extension deficit was 22°, and mean flexion 125°. There was no loss of autonomy or cognitive impairment. The complications rate was 9.5%. There were no revision surgeries. TEA proved reliable in comminuted distal humerus fracture in elderly patients. Functional results were comparable to those in the literature, and the complications rate was lower. Long-term implant survival needs confirmation to validate this option as a treatment of choice in these indications in geriatric traumatology. Retrospective non-comparative, single-center. 4. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Robust Blind Learning Algorithm for Nonlinear Equalization Using Input Decision Information.

PubMed

Xu, Lu; Huang, Defeng David; Guo, Yingjie Jay

2015-12-01

In this paper, we propose a new blind learning algorithm, namely, the Benveniste-Goursat input-output decision (BG-IOD), to enhance the convergence performance of neural network-based equalizers for nonlinear channel equalization. In contrast to conventional blind learning algorithms, where only the output of the equalizer is employed for updating system parameters, the BG-IOD exploits a new type of extra information, the input decision information obtained from the input of the equalizer, to mitigate the influence of the nonlinear equalizer structure on parameters learning, thereby leading to improved convergence performance. We prove that, with the input decision information, a desirable convergence capability that the output symbol error rate (SER) is always less than the input SER if the input SER is below a threshold, can be achieved. Then, the BG soft-switching technique is employed to combine the merits of both input and output decision information, where the former is used to guarantee SER convergence and the latter is to improve SER performance. Simulation results show that the proposed algorithm outperforms conventional blind learning algorithms, such as stochastic quadratic distance and dual mode constant modulus algorithm, in terms of both convergence performance and SER performance, for nonlinear equalization.

Goldmann tonometer error correcting prism: clinical evaluation.

PubMed

McCafferty, Sean; Lim, Garrett; Duncan, William; Enikov, Eniko T; Schwiegerling, Jim; Levine, Jason; Kew, Corin

2017-01-01

Clinically evaluate a modified applanating surface Goldmann tonometer prism designed to substantially negate errors due to patient variability in biomechanics. A modified Goldmann prism with a correcting applanation tonometry surface (CATS) was mathematically optimized to minimize the intraocular pressure (IOP) measurement error due to patient variability in corneal thickness, stiffness, curvature, and tear film adhesion force. A comparative clinical study of 109 eyes measured IOP with CATS and Goldmann prisms. The IOP measurement differences between the CATS and Goldmann prisms were correlated to corneal thickness, hysteresis, and curvature. The CATS tonometer prism in correcting for Goldmann central corneal thickness (CCT) error demonstrated a reduction to <±2 mmHg in 97% of a standard CCT population. This compares to only 54% with CCT error <±2 mmHg using the Goldmann prism. Equal reductions of ~50% in errors due to corneal rigidity and curvature were also demonstrated. The results validate the CATS prism's improved accuracy and expected reduced sensitivity to Goldmann errors without IOP bias as predicted by mathematical modeling. The CATS replacement for the Goldmann prism does not change Goldmann measurement technique or interpretation.

40-Gb/s PAM4 with low-complexity equalizers for next-generation PON systems

NASA Astrophysics Data System (ADS)

Tang, Xizi; Zhou, Ji; Guo, Mengqi; Qi, Jia; Hu, Fan; Qiao, Yaojun; Lu, Yueming

2018-01-01

In this paper, we demonstrate 40-Gb/s four-level pulse amplitude modulation (PAM4) transmission with 10 GHz devices and low-complexity equalizers for next-generation passive optical network (PON) systems. Simple feed-forward equalizer (FFE) and decision feedback equalizer (DFE) enable 20 km fiber transmission while high-complexity Volterra algorithm in combination with FFE and DFE can extend the transmission distance to 40 km. A simplified Volterra algorithm is proposed for reducing computational complexity. Simulation results show that the simplified Volterra algorithm reduces up to ∼75% computational complexity at a relatively low cost of only 0.4 dB power budget. At a forward error correction (FEC) threshold of 10-3 , we achieve 31.2 dB and 30.8 dB power budget over 40 km fiber transmission using traditional FFE-DFE-Volterra and our simplified FFE-DFE-Volterra, respectively.

Special cascade LMS equalization scheme suitable for 60-GHz RoF transmission system.

PubMed

Liu, Siming; Shen, Guansheng; Kou, Yanbin; Tian, Huiping

2016-05-16

We design a specific cascade least mean square (LMS) equalizer and to the best of our knowledge, it is the first time this kind of equalizer has been employed for 60-GHz millimeter-wave (mm-wave) radio over fiber (RoF) system. The proposed cascade LMS equalizer consists of two sub-equalizers which are designated for optical and wireless channel compensations, respectively. We control the linear and nonlinear factors originated from optical link and wireless link separately. The cascade equalization scheme can keep the nonlinear distortions of the RoF system in a low degree. We theoretically and experimentally investigate the parameters of the two sub-equalizers to reach their best performances. The experiment results show that the cascade equalization scheme has a faster convergence speed. It needs a training sequence with a length of 10000 to reach its stable status, which is only half as long as the traditional LMS equalizer needs. With the utility of a proposed equalizer, the 60-GHz RoF system can successfully transmit 5-Gbps BPSK signal over 10-km fiber and 1.2-m wireless link under forward error correction (FEC) limit 10^-3. An improvement of 4dBm and 1dBm in power sensitivity at BER 10^-3 over traditional LMS equalizer can be observed when the signals are transmitted through Back-to-Back (BTB) and 10-km fiber 1.2-m wireless links, respectively.

A methodology based on reduced complexity algorithm for system applications using microprocessors

NASA Technical Reports Server (NTRS)

Yan, T. Y.; Yao, K.

1988-01-01

The paper considers a methodology on the analysis and design of a minimum mean-square error criterion linear system incorporating a tapped delay line (TDL) where all the full-precision multiplications in the TDL are constrained to be powers of two. A linear equalizer based on the dispersive and additive noise channel is presented. This microprocessor implementation with optimized power of two TDL coefficients achieves a system performance comparable to the optimum linear equalization with full-precision multiplications for an input data rate of 300 baud.

Migration of Asteroidal Dust

NASA Technical Reports Server (NTRS)

Ipatov, S. I.; Mather, J. C.

2003-01-01

Using the Bulirsh Stoer method of integration, we investigated the migration of dust particles under the gravitational influence of all planets, radiation pressure, Poynting Robertson drag and solar wind drag for equal to 0.01, 0.05, 0.1, 0.25, and 0.4. For silicate particles such values of correspond to diameters equal to about 40, 9, 4, 2, and 1 microns, respectively [1]. The relative error per integration step was taken to be less than 10sup-8. Initial orbits of the particles were close to the orbits of the first numbered mainbelt asteroids.

Positive dwell time algorithm with minimum equal extra material removal in deterministic optical surfacing technology.

PubMed

Li, Longxiang; Xue, Donglin; Deng, Weijie; Wang, Xu; Bai, Yang; Zhang, Feng; Zhang, Xuejun

2017-11-10

In deterministic computer-controlled optical surfacing, accurate dwell time execution by computer numeric control machines is crucial in guaranteeing a high-convergence ratio for the optical surface error. It is necessary to consider the machine dynamics limitations in the numerical dwell time algorithms. In this paper, these constraints on dwell time distribution are analyzed, and a model of the equal extra material removal is established. A positive dwell time algorithm with minimum equal extra material removal is developed. Results of simulations based on deterministic magnetorheological finishing demonstrate the necessity of considering machine dynamics performance and illustrate the validity of the proposed algorithm. Indeed, the algorithm effectively facilitates the determinacy of sub-aperture optical surfacing processes.

Decision-Making under Risk of Loss in Children

PubMed Central

Steelandt, Sophie; Broihanne, Marie-Hélène; Romain, Amélie; Thierry, Bernard; Dufour, Valérie

2013-01-01

In human adults, judgment errors are known to often lead to irrational decision-making in risky contexts. While these errors can affect the accuracy of profit evaluation, they may have once enhanced survival in dangerous contexts following a “better be safe than sorry” rule of thumb. Such a rule can be critical for children, and it could develop early on. Here, we investigated the rationality of choices and the possible occurrence of judgment errors in children aged 3 to 9 years when exposed to a risky trade. Children were allocated with a piece of cookie that they could either keep or risk in exchange of the content of one cup among 6, visible in front of them. In the cups, cookies could be of larger, equal or smaller sizes than the initial allocation. Chances of losing or winning were manipulated by presenting different combinations of cookie sizes in the cups (for example 3 large, 2 equal and 1 small cookie). We investigated the rationality of children's response using the theoretical models of Expected Utility Theory (EUT) and Cumulative Prospect Theory. Children aged 3 to 4 years old were unable to discriminate the profitability of exchanging in the different combinations. From 5 years, children were better at maximizing their benefit in each combination, their decisions were negatively induced by the probability of losing, and they exhibited a framing effect, a judgment error found in adults. Confronting data to the EUT indicated that children aged over 5 were risk-seekers but also revealed inconsistencies in their choices. According to a complementary model, the Cumulative Prospect Theory (CPT), they exhibited loss aversion, a pattern also found in adults. These findings confirm that adult-like judgment errors occur in children, which suggests that they possess a survival value. PMID:23349682

Decision-making under risk of loss in children.

PubMed

Steelandt, Sophie; Broihanne, Marie-Hélène; Romain, Amélie; Thierry, Bernard; Dufour, Valérie

2013-01-01

In human adults, judgment errors are known to often lead to irrational decision-making in risky contexts. While these errors can affect the accuracy of profit evaluation, they may have once enhanced survival in dangerous contexts following a "better be safe than sorry" rule of thumb. Such a rule can be critical for children, and it could develop early on. Here, we investigated the rationality of choices and the possible occurrence of judgment errors in children aged 3 to 9 years when exposed to a risky trade. Children were allocated with a piece of cookie that they could either keep or risk in exchange of the content of one cup among 6, visible in front of them. In the cups, cookies could be of larger, equal or smaller sizes than the initial allocation. Chances of losing or winning were manipulated by presenting different combinations of cookie sizes in the cups (for example 3 large, 2 equal and 1 small cookie). We investigated the rationality of children's response using the theoretical models of Expected Utility Theory (EUT) and Cumulative Prospect Theory. Children aged 3 to 4 years old were unable to discriminate the profitability of exchanging in the different combinations. From 5 years, children were better at maximizing their benefit in each combination, their decisions were negatively induced by the probability of losing, and they exhibited a framing effect, a judgment error found in adults. Confronting data to the EUT indicated that children aged over 5 were risk-seekers but also revealed inconsistencies in their choices. According to a complementary model, the Cumulative Prospect Theory (CPT), they exhibited loss aversion, a pattern also found in adults. These findings confirm that adult-like judgment errors occur in children, which suggests that they possess a survival value.

An improved adaptive interpolation clock recovery loop based on phase splitting algorithm for coherent optical communication system

NASA Astrophysics Data System (ADS)

Liu, Xuan; Liu, Bo; Zhang, Li-jia; Xin, Xiang-jun; Zhang, Qi; Wang, Yong-jun; Tian, Qing-hua; Tian, Feng; Mao, Ya-ya

2018-01-01

Traditional clock recovery scheme achieves timing adjustment by digital interpolation, thus recovering the sampling sequence. Based on this, an improved clock recovery architecture joint channel equalization for coherent optical communication system is presented in this paper. The loop is different from the traditional clock recovery. In order to reduce the interpolation error caused by the distortion in the frequency domain of the interpolator and to suppress the spectral mirroring generated by the sampling rate change, the proposed algorithm joint equalization, improves the original interpolator in the loop, along with adaptive filtering, and makes error compensation for the original signals according to the balanced pre-filtering signals. Then the signals are adaptive interpolated through the feedback loop. Furthermore, the phase splitting timing recovery algorithm is adopted in this paper. The time error is calculated according to the improved algorithm when there is no transition between the adjacent symbols, making calculated timing error more accurate. Meanwhile, Carrier coarse synchronization module is placed before the beginning of timing recovery to eliminate the larger frequency offset interference, which effectively adjust the sampling clock phase. In this paper, the simulation results show that the timing error is greatly reduced after the loop is changed. Based on the phase splitting algorithm, the BER and MSE are better than those in the unvaried architecture. In the fiber channel, using MQAM modulation format, after 100 km-transmission of single-mode fiber, especially when ROF(roll-off factor) values tends to 0, the algorithm shows a better clock performance under different ROFs. When SNR values are less than 8, the BER could achieve 10-2 to 10-1 magnitude. Furthermore, the proposed timing recovery is more suitable for the situation with low SNR values.

Low-Complexity Polynomial Channel Estimation in Large-Scale MIMO With Arbitrary Statistics

NASA Astrophysics Data System (ADS)

Shariati, Nafiseh; Bjornson, Emil; Bengtsson, Mats; Debbah, Merouane

2014-10-01

This paper considers pilot-based channel estimation in large-scale multiple-input multiple-output (MIMO) communication systems, also known as massive MIMO, where there are hundreds of antennas at one side of the link. Motivated by the fact that computational complexity is one of the main challenges in such systems, a set of low-complexity Bayesian channel estimators, coined Polynomial ExpAnsion CHannel (PEACH) estimators, are introduced for arbitrary channel and interference statistics. While the conventional minimum mean square error (MMSE) estimator has cubic complexity in the dimension of the covariance matrices, due to an inversion operation, our proposed estimators significantly reduce this to square complexity by approximating the inverse by a L-degree matrix polynomial. The coefficients of the polynomial are optimized to minimize the mean square error (MSE) of the estimate. We show numerically that near-optimal MSEs are achieved with low polynomial degrees. We also derive the exact computational complexity of the proposed estimators, in terms of the floating-point operations (FLOPs), by which we prove that the proposed estimators outperform the conventional estimators in large-scale MIMO systems of practical dimensions while providing a reasonable MSEs. Moreover, we show that L needs not scale with the system dimensions to maintain a certain normalized MSE. By analyzing different interference scenarios, we observe that the relative MSE loss of using the low-complexity PEACH estimators is smaller in realistic scenarios with pilot contamination. On the other hand, PEACH estimators are not well suited for noise-limited scenarios with high pilot power; therefore, we also introduce the low-complexity diagonalized estimator that performs well in this regime. Finally, we ...

Cognitive Impairment and Risk Factors in Elderly People Living in Fluorosis Areas in China.

PubMed

Li, Mang; Gao, Yanhui; Cui, Jing; Li, Yuanyuan; Li, Bingyun; Liu, Yang; Sun, Jing; Liu, Xiaona; Liu, Hongxu; Zhao, Lijun; Sun, Dianjun

2016-07-01

Residents living in fluorosis areas generally experienced long-term exposure to excessive fluoride in drinking water. The adverse effects of high fluoride levels on the nervous system have been studied; however, the effect of fluoride exposure on cognitive functions of elderly people in fluorosis areas is rarely reported. This study was aimed to find out the potential risk factors of cognitive impairment among elderly people who lived in fluorosis areas of China. A total of 511 subjects, aged 60 years or above, were investigated in fluorosis areas of Heilongjiang Province, Inner Mongolia Autonomous Region, Qinghai Province, and Xinjiang Uygur Autonomous Region. The Mini-Mental State Examination (MMSE) was used to examine cognitive functions of the study subjects. Based on the MMSE scores, the study subjects were divided into normal group and cognitive impairment group that consisted of mild, moderate, and severe groups. Multivariable logistic regression showed that a higher risk of cognitive impairment was associated with increased age and decreased education levels. Multiple linear regression analysis revealed that MMSE scores were negatively associated with serum homocysteine (Hcy) levels. However, both urinary fluoride and serum Hcy levels in the normal group were not the lowest among the four groups. Spearman's correlation analysis showed that urinary fluoride levels were positively correlated with serum Hcy (r s = 0.209, P < 0.01). Our study suggests that people with cognitive impairment in fluorosis areas have elevated serum Hcy levels, which was positively correlated with urinary fluoride concentrations. A certain low dose of fluoride intake may play a potential protective rather than harmful role in cognitive functions; however, high fluoride exposure is a potential risk factor for cognitive impairment.

Physical Frailty, Cognitive Impairment, and the Risk of Neurocognitive Disorder in the Singapore Longitudinal Ageing Studies.

PubMed

Feng, Liang; Nyunt, Ma Shwe Zin; Gao, Qi; Feng, Lei; Lee, Tih Shih; Tsoi, Tung; Chong, Mei Sian; Lim, Wee Shiong; Collinson, Simon; Yap, Philip; Yap, Keng Bee; Ng, Tze Pin

2017-03-01

The independent and combined effects of physical and cognitive domains of frailty in predicting the development of mild cognitive impairment (MCI) or dementia are not firmly established. This study included cross-sectional and longitudinal analyses of physical frailty (Cardiovascular Health Study criteria), cognitive impairment (Mini-Mental State Examination [MMSE]), and neurocognitive disorder (DSM-5 criteria) among 1,575 community-living Chinese older adults from the Singapore Longitudinal Ageing Studies. At baseline, 2% were frail, 32% were prefrail, and 9% had cognitive impairment (MMSE score < 23). Frailty at baseline was significantly associated with prevalent cognitive impairment. Physical frailty categories were not significantly associated with incident NCD, but continuous physical frailty score and MMSE score showed significant individual and joint associations with incident mild NCD and dementia. Compared with those who were robust and cognitively normal, prefrail or frail old adults without cognitive impairment had no increased risk of incident NCD, but elevated odds of association with incident NCD were observed for robust with cognitive impairment (odds ratio [OR] = 4.04, p < .001), prefrail with cognitive impairment (OR = 2.22, p = .044), and especially for frail with cognitive impairment (OR = 6.37, p = .005). The prevalence of co-existing frailty and cognitive impairment (cognitive frailty) was 1% (95% confidence interval [CI]: 0.5-1.4), but was higher among participants aged 75 and older at 5.0% (95% CI: 1.8-8.1). Physical frailty is associated with increased prevalence and incidence of cognitive impairment, and co-existing physical frailty and cognitive impairment confers additionally greater risk of incident NCD. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.