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Fulltext A machine learning approach of predicting high potential archers by means of physical fitness indicators

Muazu Musa R, P P Abdul Majeed A, Taha Z, Chang SW, Ab Nasir AF, Abdullah MR

PLoS One, 2019;14(1):e0209638.
PMID: 30605456 DOI: 10.1371/journal.pone.0209638

k-nearest neighbour (k-NN) has been shown to be an effective learning algorithm for classification and prediction. However, the application of k-NN for prediction and classification in specific sport is still in its infancy. The present study classified and predicted high and low potential archers from a set of physical fitness variables trained on a variation of k-NN algorithms and logistic regression. 50 youth archers with the mean age and standard deviation of (17.0 ± 0.56) years drawn from various archery programmes completed a one end archery shooting score test. Standard fitness measurements of the handgrip, vertical jump, standing broad jump, static balance, upper muscle strength and the core muscle strength were conducted. Multiple linear regression was utilised to ascertain the significant variables that affect the shooting score. It was demonstrated from the analysis that core muscle strength and vertical jump were statistically significant. Hierarchical agglomerative cluster analysis (HACA) was used to cluster the archers based on the significant variables identified. k-NN model variations, i.e., fine, medium, coarse, cosine, cubic and weighted functions as well as logistic regression, were trained based on the significant performance variables. The HACA clustered the archers into high potential archers (HPA) and low potential archers (LPA). The weighted k-NN outperformed all the tested models at itdemonstrated reasonably good classification on the evaluated indicators with an accuracy of 82.5 ± 4.75% for the prediction of the HPA and the LPA. Moreover, the performance of the classifiers was further investigated against fresh data, which also indicates the efficacy of the weighted k-NN model. These findings could be valuable to coaches and sports managers to recognise high potential archers from a combination of the selected few physical fitness performance indicators identified which would subsequently save cost, time and energy for a talent identification programme.

Matched MeSH terms: Psychomotor Performance/physiology
Orthostatic blood pressure changes and physical, functional and cognitive performance: the MELoR study

Saedon NI, Frith J, Goh CH, Ahmad WAW, Khor HM, Tan KM, et al.

Clin Auton Res, 2020 04;30(2):129-137.
PMID: 31696333 DOI: 10.1007/s10286-019-00647-3

PURPOSE: Consensus definitions currently define initial orthostatic hypotension (IOH) as ≥ 40 mmHg systolic (SBP) or ≥ 20 mmHg in diastolic blood pressure (DBP) reductions within 15 s of standing, while classical orthostatic hypotension (COH) is defined as a sustained reduction ≥ 20 mmHg SBP or ≥ 10 mmHg SBP within 3 min of standing. The clinical relevance of the aforementioned criteria remains unclear. The present study aimed to determine factors influencing postural blood pressure changes and their relationship with physical, functional and cognitive performance in older adults.
METHODS: Individuals aged ≥ 55 years were recruited through the Malaysian Elders Longitudinal Research (MELoR) study and continuous non-invasive BP was monitored over 5 min of supine rest and 3 min of standing. Physical performance was measured using the timed-up-and-go test, functional reach, handgrip and Lawton's functional ability scale. Cognition was measured with the Montreal Cognitive Assessment. Participants were categorized according to BP responses into four categories according to changes in SBP/DBP reductions from supine to standing:

Matched MeSH terms: Psychomotor Performance/physiology*
A comparative study of sevoflurane sedation with nitrous oxide sedation for dental surgery

Wang CY, Chiu CL, Har KO, Chan C, Rahman ZA

Int J Oral Maxillofac Surg, 2002 Oct;31(5):506-10.
PMID: 12418566

This study compares the use of inhalation sedation using sevoflurane (group S) with inhalation sedation using nitrous oxide (group N) in patients undergoing bilateral extraction of third molar teeth under local anaesthesia. The study was designed as a cross-over study. Seventeen ASA I, day surgery patients were studied. Patients were randomly allocated to receive either 8 l/min 50% nitrous oxide in oxygen (group N) or same flow of 1% sevoflurane (group S) for the first procedure. Each patient then had the alternate method of sedation for the second procedure. There were no significant differences between the methods in patient co-operation and surgeon's satisfaction with sedation. Psychomotor tests were comparable in both groups. The patients were significantly more sedated in the group S compared to group N (P=0.004). Significantly more patients complained of an unpleasant odour group S (P<0.01) but none withdrew from the study for this reason. No adverse cardiorespiratory effects resulted from sevoflurane or nitrous oxide sedation. Both methods gave good amnesia during the procedure. There was high acceptance of both methods and the patients rated the technique as equally satisfactory. We conclude that inhalation sedation with sevoflurane is a suitable alternative method to nitrous oxide sedation.

Matched MeSH terms: Psychomotor Performance/drug effects
A double-blind placebo-controlled trial of zopiclone 7.5 mg and temazepam 20 mg in insomnia

Ngen CC, Hassan R

Int Clin Psychopharmacol, 1990 Jul;5(3):165-71.
PMID: 2230060

Zopiclone, a cyclopyrrolone with hypnotic properties was compared with temazepam and placebo in the treatment of insomnia. After a week's washout period, suitable subjects were allocated at random to zopiclone 7.5 mg or temazepam 20 mg or placebo for 2 weeks. Measurements of psychomotor function using the Leed's psychomotor tester and letter cancellation were carried out on day 0, 7 and 14. Sleep latency, duration of sleep and number of times waking during the night were recorded on a sleep diary filled by the subjects nightly. Forty-four subjects completed the trial, 15 taking zopiclone, 16 taking temazepam and 10 taking placebo. Both zopiclone and temazepam had significant hypnotic properties when compared to placebo. Zopiclone increased total sleep time in both weeks of the trial while temazepam increased sleep time in the first week only. There was no significant deterioration in psychomotor performance at the end of both weeks for zopiclone. Critical flicker fusion was significantly increased in subjects on temazepam. There were no abnormalities for both zopiclone and temazepam subjects in the blood picture, renal profile, liver function, urine and ECG before and after the study. Zopiclone is an effective hypnotic comparable to temazepam.

Matched MeSH terms: Psychomotor Performance/drug effects
Docosahexaenoic acid-concentrated fish oil supplementation in subjects with mild cognitive impairment (MCI): a 12-month randomised, double-blind, placebo-controlled trial

Lee LK, Shahar S, Chin AV, Yusoff NA

Psychopharmacology (Berl), 2013 Feb;225(3):605-12.
PMID: 22932777 DOI: 10.1007/s00213-012-2848-0

RATIONALE: Epidemiological studies have suggested a beneficial effect of fish oil supplementation in halting the initial progression of Alzheimer's disease. However, it remains unclear whether fish oil affects cognitive function in older people with mild cognitive impairment (MCI).
OBJECTIVES: This study investigated the effects of fish oil supplementation on cognitive function in elderly person with MCI.
METHODS: This was a 12-month, randomised, double-blind, placebo-controlled study using fish oil supplementation with concentrated docosahexaenoic acid (DHA). Thirty six low-socioeconomic-status elderly subjects with MCI were randomly assigned to receive either concentrated DHA fish oil (n = 18) or placebo (n = 18) capsules. The changes of memory, psychomotor speed, executive function and attention, and visual-constructive skills were assessed using cognitive tests. Secondary outcomes were safety and tolerability of the DHA concentrate.
RESULTS: The fish oil group showed significant improvement in short-term and working memory (F = 9.890; ηp (2) = 0.254; p

Matched MeSH terms: Psychomotor Performance/drug effects*
Heterogeneity in brain functional changes of cognitive processing in ADHD across age: A systematic review of task-based fMRI studies

Yap KH, Abdul Manan H, Sharip S

Behav Brain Res, 2021 01 15;397:112888.
PMID: 32882284 DOI: 10.1016/j.bbr.2020.112888

This review aims to establish the cognitive processing of patients with attention-deficit hyperactive disorder (ADHD) across age. Functional magnetic resonance imaging (fMRI) studies on children and adult populations were conducted, thus delineating deficits that could have been maintained and ameliorated across age. This allowed for the examination of the correlation between patterns of brain activation and the corresponding development of functional heterogeneity in ADHD. A systematic literature search of fMRI studies on ADHD was conducted using the PubMed and Scopus electronic databases based on PRISMA guidelines. References and citations were verified in Scopus database. The present study has identified 14 studies on children, 16 studies on adults, and one study on both populations of ADHD consisting of 1371 participants. Functional heterogeneity is present in ADHD across age, which can manifest either as different brain activation patterns, intra-subject variability, or both. This is shown in the increased role of the frontal regions and the specialized network in adults with ADHD from inefficient non-specific activation in childhood. Functional heterogeneity may manifest when delayed maturation is insufficient to normalize frontal lobe functions.

Matched MeSH terms: Psychomotor Performance/physiology*
Comparison of gait parameters across three attentional loading conditions during timed up and go test in stroke survivors

Manaf H, Justine M, Ting GH, Latiff LA

Top Stroke Rehabil, 2014 Mar-Apr;21(2):128-36.
PMID: 24710973 DOI: 10.1310/tsr2102-128

Little is known about the effects of attentional loading on performance of turning during walking in individuals with stroke.

Matched MeSH terms: Psychomotor Performance
Relating vision status to academic achievement among year-2 school children in Malaysia

Chen AH, Bleything W, Lim YY

Optometry, 2011 May;82(5):267-73.
PMID: 21524597 DOI: 10.1016/j.optm.2011.02.004

Vision affects daily activities, but of particular importance is the impact upon the learning process. Many studies have been conducted to establish the relationship between vision problems and academic performance. The results are varied, however, and suggest additional research is needed with particular care given to study design.

Matched MeSH terms: Psychomotor Performance
Is First-Order Vector Autoregressive Model Optimal for fMRI Data?

Ting CM, Seghouane AK, Khalid MU, Salleh ShH

Neural Comput, 2015 Sep;27(9):1857-71.
PMID: 26161816 DOI: 10.1162/NECO_a_00765

We consider the problem of selecting the optimal orders of vector autoregressive (VAR) models for fMRI data. Many previous studies used model order of one and ignored that it may vary considerably across data sets depending on different data dimensions, subjects, tasks, and experimental designs. In addition, the classical information criteria (IC) used (e.g., the Akaike IC (AIC)) are biased and inappropriate for the high-dimensional fMRI data typically with a small sample size. We examine the mixed results on the optimal VAR orders for fMRI, especially the validity of the order-one hypothesis, by a comprehensive evaluation using different model selection criteria over three typical data types--a resting state, an event-related design, and a block design data set--with varying time series dimensions obtained from distinct functional brain networks. We use a more balanced criterion, Kullback's IC (KIC) based on Kullback's symmetric divergence combining two directed divergences. We also consider the bias-corrected versions (AICc and KICc) to improve VAR model selection in small samples. Simulation results show better small-sample selection performance of the proposed criteria over the classical ones. Both bias-corrected ICs provide more accurate and consistent model order choices than their biased counterparts, which suffer from overfitting, with KICc performing the best. Results on real data show that orders greater than one were selected by all criteria across all data sets for the small to moderate dimensions, particularly from small, specific networks such as the resting-state default mode network and the task-related motor networks, whereas low orders close to one but not necessarily one were chosen for the large dimensions of full-brain networks.

Matched MeSH terms: Psychomotor Performance
MRI Markers of Mixed Pathology and Cognitive Impairment in Multiethnic Asians

Tan CH, Hilal S, Xu X, Vrooman H, Cheng CY, Wong TY, et al.

J Alzheimers Dis, 2020;73(4):1501-1509.
PMID: 31958085 DOI: 10.3233/JAD-190866

There is a need to elucidate the combined influence of neurodegeneration and cerebrovascular disease (CeVD) on cognitive impairment, especially in diverse populations. Here, we evaluated 840 multiethnic individuals (mean age = 70.18) across the disease spectrum from the Epidemiology of Dementia in Singapore study. First, we determined whether a validated quantitative MRI score of mixed pathology is associated with clinical diagnosis and whether the score differed between ethnicities (Chinese, Malays, and Indians). We then evaluated whether the score was associated with multidomain cognitive impairment and if additional measures of CeVD were further associated with cognitive impairment. We found that lower quantitative MRI scores were associated with severity of clinical diagnosis and Chinese individuals had the highest quantitative MRI scores, followed by Indians and Malays. Lower quantitative MRI scores were also associated with lower performance in attention, language, visuoconstruction, visuomotor, visual, and verbal memory domains. Lastly, the presence of intracranial stenosis and cortical cerebral microinfarcts, but not cerebral microbleeds, were associated with memory performance beyond quantitative MRI scores. Taken together, our results demonstrate the utility of using multiple MRI markers of neurodegeneration and CeVD for identifying multiethnic Asians with the greatest cognitive impairment due to mixed pathology.

Matched MeSH terms: Psychomotor Performance
Adenylosuccinate lyase deficiency in a Malaysian patient, with novel adenylosuccinate lyase gene mutations

Chen BC, McGown IN, Thong MK, Pitt J, Yunus ZM, Khoo TB, et al.

J Inherit Metab Dis, 2010 Dec;33 Suppl 3:S159-62.
PMID: 20177786 DOI: 10.1007/s10545-010-9056-z

Most cases of adenylosuccinate lyase (ADSL OMIM 103050) deficiency reported to date are confined to the various European ethnic groups. We report on the first Malaysian case of ADSL deficiency, which appears also to be the first reported Asian case. The case was diagnosed among a cohort of 450 patients with clinical features of psychomotor retardation, global developmental delay, seizures, microcephaly and/or autistic behaviour. The patient presented with frequent convulsions and severe myoclonic jerk within the first few days of life and severe psychomotor retardation. The high performance liquid chromatography (HPLC) profile of the urine revealed the characteristic biochemical markers of succinyladenosine (S-Ado) and succinyl-aminoimidazole carboximide riboside (SAICAr). The urinary S-Ado/SAICAr ratio was found to be 1.02 (type I ADSL deficiency). The patient was compound heterozygous for two novel mutations, c.445C > G (p.R149G) and c.774_778insG (p.A260GfsX24).

Matched MeSH terms: Psychomotor Performance