Predicting individual acclimation to the cross-coupled illusion for artificial gravity

2021 ◽  
pp. 1-12
Author(s):  
Kathrine N. Bretl ◽  
Torin K. Clark
Keyword(s):  
Individual Differences ◽  
Negative Correlation ◽  
Cross Validation ◽  
Significant Negative Correlation ◽  
Linear Increase ◽  
Artificial Gravity ◽  
Rotation Axes ◽  
The Cross ◽  
Leave One Out ◽  
Fast Spin

BACKGROUND: The cross-coupled (CC) illusion and associated motion sickness limits the tolerability of fast-spin-rate centrifugation for artificial gravity implementation. Humans acclimate to the CC illusion through repeated exposure; however, substantial inter-individual differences in acclimation exist, which remain poorly understood. To address this, we investigated several potential predictors of individual acclimation to the CC illusion. METHODS: Eleven subjects were exposed to the CC illusion for up to 50 25-minute acclimation sessions. The metric of acclimation rate was calculated as the slope of each subject’s linear increase in spin rate across sessions. As potential predictors of acclimation rate, we gathered age, gender, demographics, and activity history, and measured subjects’ vestibular perceptual thresholds in the yaw, pitch, and roll rotation axes. RESULTS: We found a significant, negative correlation (p = 0.025) between subjects’ acclimation rate and roll threshold, suggesting lower thresholds yielded faster acclimation. Additionally, a leave-one-out cross-validation analysis indicated that roll thresholds are predictive of acclimation rates. Correlations between acclimation and other measures were not found but were difficult to assess within our sample. CONCLUSIONS: The ability to predict individual differences in CC illusion acclimation rate using roll thresholds is critical to optimizing acclimation training, improving the feasibility of fast-rotation, short-radius centrifugation for artificial gravity.

Thrombin generation in paediatric patients with congenital heart disease

2008 ◽  
Vol 28 (S 01) ◽  
pp. S61-S66 ◽  
Author(s):  
G. Cvirn ◽  
A. Rosenkranz ◽  
B. Leschnik ◽  
W. Raith ◽  
W. Muntean ◽  
...  
Keyword(s):  
Congenital Heart Disease ◽  
Heart Disease ◽  
Negative Correlation ◽  
Congenital Heart ◽  
Thrombin Generation ◽  
Significant Negative Correlation ◽  
Peak Height ◽  
Global Test ◽  
Paediatric Patients ◽  
Age Range

SummaryThrombin generation was studied in paediatric patients with congenital heart disease (CHD) undergoing cardiac surgery using the calibrated automated thrombography (CAT) in terms of the lag time until the onset of thrombin formation, time to thrombin peak maximum (TTP), endogenous thrombin potential (ETP), and thrombin peak height. The suitability to determine the coagulation status of these patients was investigated. Patients, material, methods: CAT data of 40 patients with CHD (age range from newborn to 18 years) were compared to data using standard coagulation parameters such as prothrombin (FII), antithrombin (AT), tissue factor pathway inhibitor (TFPI), prothrombin fragment 1.2 (F 1.2), thrombin-antithrombin (TAT), activated partial thromboplastin time (aPTT), and prothrombin time (PT). Results: A significant positive correlation was seen between ETP and FII (p < 0.01; r = 0.369), as well as between peak height and F II (p < 0.01; r = 0.483). A significant negative correlation was seen between ETP and TFPI values (p < 0.05; r = –0.225) while no significant correlation was seen between peak height and TFPI. A significant negative correlation was seen between F 1.2 generation and ETP (p < 0.05; r = –0.254) and between F 1.2 generation and peak height (p < 0.05; r = –0.236). No correlation was seen between AT and ETP or peak. Conclusions: CAT is a good global test reflecting procoagulatory and inhibitory factors of the haemostatic system in paediatric patients with CHD.

Negative Correlation Between Serum Levels of Homocysteine and Apolipoprotein M

2019 ◽  
Vol 19 (2) ◽  
pp. 120-126
Author(s):  
J. Wei ◽  
Y. Yu ◽  
Y. Feng ◽  
J. Zhang ◽  
Q. Jiang ◽  
...  
Keyword(s):  
Negative Correlation ◽  
Hepg2 Cells ◽  
Serum Levels ◽  
Significant Negative Correlation ◽  
Mrna Levels ◽  
Rt Pcr ◽  
Apolipoprotein M ◽  
Protein Mass ◽  
Protein Levels ◽  
Phosphoinositide 3 Kinase

Background: Homocysteine (Hcy) has been suggested as an independent risk factor for atherosclerosis. Apolipoprotein M (apoM) is a constituent of the HDL particles. The goal of this study was to examine the serum levels of homocysteine and apoM and to determine whether homocysteine influences apoM synthesis. Methods: Serum levels of apoM and Hcy in 17 hyperhomocysteinemia (HHcy) patients and 19 controls were measured and their correlations were analyzed. Different concentrations of homocysteine (Hcy) and LY294002, a specific phosphoinositide 3- kinase (PI3K) inhibitor, were used to treat HepG2 cells. The mRNA levels were determined by RT-PCR and the apoM protein mass was measured by western blot. Results: We found that decreased serum apoM levels corresponded with serum HDL levels in HHcy patients, while the serum apoM levels showed a statistically significant negative correlation with the serum Hcy levels. Moreover, apoM mRNA and protein levels were significantly decreased after the administration of Hcy in HepG2 cells, and this effect could be abolished by addition of LY294002. Conclusions: resent study demonstrates that Hcy downregulates the expression of apoM by mechanisms involving the PI3K signal pathway.

scholarly journals Ant Colony-Based Hyperparameter Optimisation in Total Variation Reconstruction in X-ray Computed Tomography

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 591
Author(s):  
Manasavee Lohvithee ◽  
Wenjuan Sun ◽  
Stephane Chretien ◽  
Manuchehr Soleimani
Keyword(s):  
Computed Tomography ◽  
Total Variation ◽  
Cross Validation ◽  
Ant Colony ◽  
Reference Image ◽  
X Ray ◽  
X Ray Computed ◽  
Hyperparameter Selection ◽  
The Cross ◽  
Optimal Set

In this paper, a computer-aided training method for hyperparameter selection of limited data X-ray computed tomography (XCT) reconstruction was proposed. The proposed method employed the ant colony optimisation (ACO) approach to assist in hyperparameter selection for the adaptive-weighted projection-controlled steepest descent (AwPCSD) algorithm, which is a total-variation (TV) based regularisation algorithm. During the implementation, there was a colony of artificial ants that swarm through the AwPCSD algorithm. Each ant chose a set of hyperparameters required for its iterative CT reconstruction and the correlation coefficient (CC) score was given for reconstructed images compared to the reference image. A colony of ants in one generation left a pheromone through its chosen path representing a choice of hyperparameters. Higher score means stronger pheromones/probabilities to attract more ants in the next generations. At the end of the implementation, the hyperparameter configuration with the highest score was chosen as an optimal set of hyperparameters. In the experimental results section, the reconstruction using hyperparameters from the proposed method was compared with results from three other cases: the conjugate gradient least square (CGLS), the AwPCSD algorithm using the set of arbitrary hyperparameters and the cross-validation method.The experiments showed that the results from the proposed method were superior to those of the CGLS algorithm and the AwPCSD algorithm using the set of arbitrary hyperparameters. Although the results of the ACO algorithm were slightly inferior to those of the cross-validation method as measured by the quantitative metrics, the ACO algorithm was over 10 times faster than cross—Validation. The optimal set of hyperparameters from the proposed method was also robust against an increase of noise in the data and can be applicable to different imaging samples with similar context. The ACO approach in the proposed method was able to identify optimal values of hyperparameters for a dataset and, as a result, produced a good quality reconstructed image from limited number of projection data. The proposed method in this work successfully solves a problem of hyperparameters selection, which is a major challenge in an implementation of TV based reconstruction algorithms.

scholarly journals Daytime nap and nighttime breastfeeding are associated with toddlers’ nighttime sleep

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Machiko Nakagawa ◽  
Hidenobu Ohta ◽  
Rinshu Shimabukuro ◽  
Yoko Asaka ◽  
Takayo Nakazawa ◽  
...  
Keyword(s):  
Sleep Duration ◽  
Negative Correlation ◽  
Significant Negative Correlation ◽  
Sleep Diary ◽  
Daytime Nap ◽  
Nighttime Sleep

AbstractThe purpose of the present study is to examine the association between toddlers' sleep arrangements and their nighttime sleep duration and other sleep variables. For this investigation, we performed a study in which child activity and sleep levels were recorded using actigraphy. The parents of 1.5-year-old toddlers (n = 106) were asked to attach an actigraphy unit to their child’s waist with an adjustable elastic belt and complete a sleep diary for 7 consecutive days. Questionnaires were used to assess the sleep arrangements of the toddlers. There was a significant negative correlation between nap duration and nighttime sleep duration, suggesting that longer nap sleep induces shorter nighttime sleep duration. Among the sleep arrangements, such as nighttime breastfeeding or co-sleeping, only nighttime breastfeeding predicted shorter nighttime sleep duration. Our findings indicate that shorter naps induce a longer nighttime sleep in 1.5-year-old toddlers while nighttime breastfeeding decreases their nighttime sleep duration.

scholarly journals Correlates of SARS-CoV-2 Variants on Deaths, Case Incidence and Case Fatality Ratio among the Continents for the Period of 1 December 2020 to 15 March 2021

Genes ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 1061
Author(s):  
Wajdy J. Al-Awaida ◽  
Baker Jawabrah Al Hourani ◽  
Samer Swedan ◽  
Refat Nimer ◽  
Foad Alzoughool ◽  
...  
Keyword(s):  
Negative Correlation ◽  
Significant Positive Correlation ◽  
Vaccine Development ◽  
Case Fatality ◽  
Significant Negative Correlation ◽  
Reference Sequence ◽  
Genome Sequences ◽  
Positive Correlation ◽  
Case Fatality Ratio ◽  
Epidemiological Surveys

The outbreak of coronavirus disease 2019 (COVID-19), by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has quickly developed into a worldwide pandemic. Mutations in the SARS-CoV-2 genome may affect various aspects of the disease including fatality ratio. In this study, 553,518 SARS-CoV-2 genome sequences isolated from patients from continents for the period 1 December 2020 to 15 March 2021 were comprehensively analyzed and a total of 82 mutations were identified concerning the reference sequence. In addition, associations between the mutations and the case fatality ratio (CFR), cases per million and deaths per million, were examined. The mutations having the highest frequencies among different continents were Spike_D614G and NSP12_P323L. Among the identified mutations, NSP2_T153M, NSP14_I42V and Spike_L18F mutations showed a positive correlation to CFR. While the NSP13_Y541C, NSP3_T73I and NSP3_Q180H mutations demonstrated a negative correlation to CFR. The Spike_D614G and NSP12_P323L mutations showed a positive correlation to deaths per million. The NSP3_T1198K, NS8_L84S and NSP12_A97V mutations showed a significant negative correlation to deaths per million. The NSP12_P323L and Spike_D614G mutations showed a positive correlation to the number of cases per million. In contrast, NS8_L84S and NSP12_A97V mutations showed a negative correlation to the number of cases per million. In addition, among the identified clades, none showed a significant correlation to CFR. The G, GR, GV, S clades showed a significant positive correlation to deaths per million. The GR and S clades showed a positive correlation to number of cases per million. The clades having the highest frequencies among continents were G, followed by GH and GR. These findings should be taken into consideration during epidemiological surveys of the virus and vaccine development.

387 The moderating effect of emotion regulation strategies in the relationship between insomnia severity and bedtime procrastination

SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A153-A154
Author(s):  
Huisu Jeon ◽  
Sonhye Jeoung ◽  
Goeun Kim ◽  
Hyeyoung An ◽  
Hyojin Nam ◽  
...  
Keyword(s):  
Negative Correlation ◽  
Emotional Regulation ◽  
Significant Negative Correlation ◽  
Moderating Effect ◽  
Active Regulation ◽  
Support Seeking ◽  
Regulation Strategies ◽  
Bedtime Procrastination ◽  
The Relationship ◽  
Insomnia Severity

Abstract Introduction Bedtime Procrastination (BP) is defined as the behavior of going to bed later than intended, despite the absence of external factors. Bedtime procrastination is also prevalent among insomnia patients, and is associated with various sleep problems. Recent studies suggest emotional regulation as a mechanism of the procrastination behavior that is the conceptual foundation of bedtime procrastination. Emotional regulation difficulties are also associated with insomnia, but there is still a lack of research on the relationship between insomnia, emotional regulation strategies and bedtime procrastination. Thus, the study assumed that severity of insomnia would affect bedtime procrastination, and examined the moderating effect of the emotional regulation strategies in this relationship. Methods This study was conducted in 376 adults (mean age 23.73 ±2.14 years, 84.6% females). Participants were asked to answer Bedtime procrastination scale (BPS), an emotional regulation strategy checklist, and the Insomnia severity scale (ISI). Results As a result, a significant positive correlation was found between insomnia severity and bedtime procrastination (r=.286, p&lt;.01), and avoidant/distractive regulation style (r=.101, p&lt;.05). active regulation style (r=-.172, p&lt;.01) and support seeking regulation style (r=-.102, p&lt;.01) showed a significant negative correlation with the severity of insomnia. Bedtime procrastination behavior showed significant negative correlation only with active regulation style (r=-.151, p&lt;.01). Support seeking regulation style moderated the relationship between insomnia and bedtime procrastination behavior (B=.0165, 95%, CI=.0014, .0316). The interaction effect between insomnia and support seeking regulation style was also significant (∆R^2=.0112, p&lt;.05), indicating that the effect of insomnia on bedtime procrastination depends on the level of use of the support seeking regulation style. Conclusion These findings suggest that the level of support seeking regulation style is meaningful in terms of how insomnia affects bedtime procrastination. Support (if any) This work was supported by the Ministry of Education of the Republic of Korea and the National Research Foundation of Korea(NRF-2018S1A5A8026807)

scholarly journals Evaluation of serum adropin and irisin levels and its association with anthropometric obesity indices and biochemical parameters in Type 2 diabetic patients

2021 ◽  
pp. 1-8
Author(s):  
Foad Alzoughool ◽  
Huda Al Hourani ◽  
Manar Atoum ◽  
Sajedah Bateineh ◽  
Hanan Alsheikh ◽  
...  
Keyword(s):  
Negative Correlation ◽  
Biochemical Parameters ◽  
Significant Positive Correlation ◽  
Glycosylated Hemoglobin ◽  
Significant Negative Correlation ◽  
Diabetic Patients ◽  
Positive Correlation ◽  
Obesity Indices ◽  
Group Serum

BACKGROUND/AIM: The newly described proteins adropin and irisin are a highly conserved polypeptide that plays essential roles in metabolic and energy homeostasis, insulin resistance, and fat browning. The aim of this study is to evaluate the circulating levels of serum adropin and irisin in type 2 diabetes mellitus (T2DM) patients and also to elucidate possible relationships between serum adropin and irisin levels with anthropometric obesity indices and biochemical parameters. SUBJECTS AND METHODS: Single-center prospective observational study included 90 T2DM patients referred to the diabetes outpatient clinic. Height, weight, and waist circumference (WC) were measured. Body mass index (BMI) and waist to height ratio (WHtR) were calculated. Fasting blood glucose, glycosylated hemoglobin, serum lipids, creatinine, urea, and blood urea nitrogen were evaluated. Estimated glomerular filtration rate (GFR) was calculated, serum adropin and irisin were evaluated. RESULTS: The results showed a significant positive correlation between adropin and irisin in females but not in males (r = 0.311; P = 0.042). In males’ group, serum adropin levels showed significant negative correlation with serum glucose (–0.423, P = <  0.05), HbA1C (–0.364, P = <  0.05), and GFR (–0.355, P = <  0.05). In contrast, creatinine was showed a significant positive correlation with adropin in males (0.381, P = <  0.05). In females’ group, adropin showed a significant negative correlation with weight (–0.371, P = <  0.05), BMI (–0.349, P = <  0.05), WC (–0.402, P = <  0.01), and WHtR (–0.398, P = <  0.01). Contrary, in males’ group, serum irisin levels showed significant positive correlation with weight (0.338, P = <  0.05), BMI (0.332, P = <  0.05), WC (0.409, P = <  0.01), and WHtR (0.432, P = <  0.01). CONCLUSION: This study demonstrated that, in T2DM patients, circulating serum adrpoin correlated negatively with anthropometric obesity indices of obesity in females, while serum irisin was positively correlated with anthropometric obesity indices of obesity in males.

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