Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
943
result(s) for
"Playing cards."
Sort by:
Accuracy of consumer-level and research-grade activity trackers in ambulatory settings in older adults
Wrist-worn activity trackers have experienced a tremendous growth lately and studies on the accuracy of mainstream trackers used by older adults are needed. This study explores the performance of six trackers (Fitbit Charge2, Garmin VivoSmart HR+, Philips Health Watch, Withings Pulse Ox, ActiGraph GT9X-BT, Omron HJ-72OITC) for estimating: steps, travelled distance, and heart-rate measurements for a cohort of older adults. Eighteen older adults completed a structured protocol involving walking tasks, simulated household activities, and sedentary activities. Less standardized activities were also included, such as: dusting, using a walking aid, or playing cards, in order to simulate real-life scenarios. Wrist-mounted and chest/waist-mounted devices were used. Gold-standards included treadmill, ECG-based chest strap, direct observation or video recording according to the activity and parameter. Every tracker showed a decreasing accuracy with slower walking speed, which resulted in a significant step under-counting. A large mean absolute percentage error (MAPE) was found for every monitor at slower walking speeds with the lowest reported MAPE at 2 km/h being 7.78%, increasing to 20.88% at 1.5 km/h, and 44.53% at 1 km/h. During household activities, the MAPE climbing up/down-stairs ranged from 8.38-19.3% and 10.06-19.01% (dominant and non-dominant arm), respectively. Waist-worn devices showed a more uniform performance. However, unstructured activities (e.g. dusting, playing cards), and using a walking aid represent a challenge for all wrist-worn trackers as evidenced by large MAPE (> 57.66% for dusting, > 67.32% when using a walking aid). Poor performance in travelled distance estimation was also evident during walking at low speeds and climbing up/down-stairs (MAPE > 71.44% and > 48.3%, respectively). Regarding heart-rate measurement, there was no significant difference (p-values > 0.05) in accuracy between trackers placed on the dominant or non-dominant arm. Concordant with existing literature, while the mean error was limited (between -3.57 bpm and 4.21 bpm), a single heart-rate measurement could be underestimated up to 30 beats-per-minute. This study showed a number of limitations of consumer-level wrist-based activity trackers for older adults. Therefore caution is required when used, in healthcare or in research settings, to measure activity in older adults.
Journal Article
Axiomatic Design of an automatic card dealing robot
When you’re playing card games with friends, a problem often occurs, at some point, no one wants to be the dealer. We propose an automatic card dealing robot. There are a few products on the market today that are expensive or missing critical functionality to fulfill the role of a card dealer. Our product will be more affordable and more portable than existing systems. The robot can be used in a variety of applications, for education, for the physically challenged, and of course for fun. The goal was to build a robot using Axiomatic Design methodology, with faster card dealing capabilities than a human.
Journal Article
How to Play Old Maid with Virtual Players
Old Maid is a popular card game. While typically played with three or more players, it is less enjoyable with only two people. To address this, we propose a protocol to create a virtual player, Carol, by making use of card-based cryptography when only two people, Alice and Bob, are available to play Old Maid. Specifically, we design a card-based protocol to remove any pair of cards having the same number in Carol’s hand (namely, the virtual player’s hand) without leaking any information about Carol’s hand (more than necessary); our protocol uses additional cards aside from playing cards that are used in Old Maid. Using our protocol, without any third human player, Alice and Bob can have fun with Old Maid!
Journal Article
Association of Playing Cards or Mahjong with Cognitive Function in Chinese Older Adults
Cognitive decline in older adults is a major public health threat. This study aimed to explore the association of participation in cards or mahjong with cognitive function in older adults. A total of 7308 older adults were selected from the 2018 Chinese Longitudinal Healthy Longevity Survey. A modified Mini-Mental State Examination (MMSE) was used to assess cognitive function. The participants were classified according to the frequency of playing cards or mahjong into the “regularly” (R) group, “occasionally” (O) group, or “never” (N) group. The results showed that older persons in the R group and O group had better cognitive function than those in the N group. Specifically, significant differences were found in attention and calculation, language, and total MMSE score between the R group and the N group. However, significant differences were not observed for adults aged 60–69 years old. Regression analysis indicated that playing cards or mahjong, together with age, educational level, sex, marital status, and occupation before age 60 could explain the cognitive function. The findings suggest that there is an association between participation in cards or mahjong and cognitive function in the population of Chinese older adults, and that the frequency of participation plays an important role in the association.
Journal Article
Association between playing cards/mahjong and risk of incident dementia among the Chinese older adults: a prospective cohort study
Objectives: Studies have shown that the frequent participation of the elderly in cognitive stimulation activities is associated with a reduced risk of dementia, but the prospective evidence of this association is limited. Methods: We used data from a prospective cohort study of the Chinese Longitudinal Healthy Longevity Survey (CLHLS), and included 11821 community-living Chinese individuals aged 65 years or older at 2008 baseline who were free of dementia, and were followed up every 2–3 years until 2018. Cox proportional hazards models were applied to generate the hazard ratios (HRs) and 95% confidence intervals (CIs) for analyzing the associations between the frequency of playing cards/mahjong and the incidence of dementia. Results: A total of 821 participants were diagnosed with dementia during the 10-year follow-up. The average age of patients with dementia and non dementia were 89 and 90 years old, respectively. Compared with participants who rarely or never played cards/mahjong, participants who played cards/mahjong almost every day had a significantly lower risk of dementia (HR=0.63; 95%CI, 0.42-0.95) after the multivariable-adjusted model. Similar results were observed in subgroup analyses based on sex (male:HR=0.52, 0.28-0.96; female:HR=0.62, 0.36-0.98), age(<85years:HR=0.55, 0.32-0.89), regularly exercise (yes: HR =0.44, 0.28–0.87) and MMSE score [above median (25): HR=0.66, 0.41-0.92]. Conclusions: Playing cards/mahjong in the elderly may contribute to reducing the risk of dementia.
Journal Article
Associations between cognitive activities and all-cause mortality among older adults with cognitive impairment: A prospective cohort study
Evidence on the association between cognitive activities and mortality among older adults with cognitive impairment is limited. Therefore, the study aimed to assess the association and examine whether baseline cognitive function mediates the association.
A total of 10477 older participants with cognitive impairment (median age: 95.0 [IQR: 88.0-100.0], males: 27.9%, Mini-Mental State Examination score ≤24 points) from the Chinese Longitudinal Healthy Longevity Survey conducted between 1998 and 2014 were included, with follow-up until 2018. Exposures were three prevalent cognitive activities among older adults in China: reading books/newspapers, playing cards/mah-jong, and watching TV or listening to radio, and the outcome was all-cause mortality within a 10-year follow-up period. We evaluated the association between these activities and mortality using Cox regression models and also conducted a mediation analysis to examine the role of baseline cognitive function in this association.
During a follow-up period of totaling 33632.1 person-years, there were 8763 recorded deaths (83.6%). For each cognitive activity, the risk of mortality decreased with an increased frequency of engagement in these activities. Moreover, the risk of mortality significantly decreased with a greater number of cognitive activities. With zero activities as reference, adjusted hazard ratios were 0.83 (95% CI: 0.79-0.87) for one activity, 0.76 (95% CI: 0.69-0.83) for two activities, and 0.67 (95% CI: 0.53-0.86) for three activities, respectively. Stratified and sensitivity analyses confirmed the robustness of these findings. Additionally, baseline cognitive function partially mediated the association between cognitive activities and mortality; compared to zero activities, the mediated proportions were 15.2% (95% CI: 10.9%-22.4%) for one activity, 13.4% (95% CI: 8.9%-21.3%) for two activities, and 9.3% (95% CI: 4.2%-23.4%) for three activities, respectively.
Among older adults with cognitive impairment in China, the risk of all-cause mortality significantly decreased as both the frequency and number of cognitive activities increased. Baseline cognitive function only mediated a small proportion of the benefits of cognitive activities in longevity.
Journal Article
Leisure Activity Engagement Among the Oldest Old in China, 1998–2018
Objectives. To examine the trends of leisure activity engagement among the oldest old in China for the past 2 decades. Methods. Our panel data came from the Chinese Longitudinal Healthy Longevity Survey, which systematically asked respondents about their current participation in leisure activities over a 20-year period. The final sample contained 66 789 interviews from 1998 to 2018. We applied generalized estimating equations regression models in our analysis. Results. Compared with 1998, odds ratios of television watching among Chinese oldest old individuals increased by about 2 to 3 times in 2018. Meanwhile, the odds ratio of exercise declined by 24%, mostly in men; playing cards and mah-jongg declined by about 30% for men. Results also showed that reading became less popular in the oldest old, and Chinese women tended to do more housework than before. Conclusions. Our findings indicated that Chinese oldest old persons have become more sedentary and solitary in the past 2 decades. The negative trend in leisure activity engagement among the elderly Chinese population warrants policy attention, and the urgent development of public health interventions is required to reverse such trends.
Journal Article
Card-Based Cryptographic Protocols with a Standard Deck of Cards Using Private Operations
This paper shows new kinds of card-based cryptographic protocols with a standard deck of cards using private operations. They are multi-party secure computations executed by multiple players without computers. Most card-based cryptographic protocols use a special deck of cards that consists of many cards with two kinds of marks. Though these protocols are simple and efficient, the users need to prepare such special cards. Few protocols were shown that use a standard deck of playing cards. Though the protocols with a standard deck of cards can be easily executed in our daily lives, the numbers of cards used by these protocols are larger than the ones that use the special deck of cards. This paper shows logical AND, logical XOR, and copy protocols for a standard deck of cards that use the minimum number of cards. Any Boolean functions can be computed with a combination of the above protocols. The new protocols use private operations that are executed by a player at a place where the other players cannot see. The results show the effectiveness of private operations in card-based cryptographic protocols. This paper also shows protocols that use private input operations. When each player privately inputs his/her secret value, this type of protocol is used. Last, we show asymmetric card protocols to further reduce the number of cards.
Journal Article