Fishing out collective memory of migratory schools

Animals form groups for many reasons, but there are costs and benefits associated with group formation. One of the benefits is collective memory. In groups on the move, social interactions play a crucial role in the cohesion and the ability to make consensus decisions. When migrating from spawning to feeding areas, fish schools need to retain a collective memory of the destination site over thousands of kilometres, and changes in group formation or individual preference can produce sudden changes in migration pathways. We propose a modelling framework, based on stochastic adaptive networks, that can reproduce this collective behaviour. We assume that three factors control group formation and school migration behaviour: the intensity of social interaction, the relative number of informed individuals and the strength of preference that informed individuals have for a particular migration area. We treat these factors independently and relate the individuals’ preferences to the experience and memory for certain migration sites. We demonstrate that removal of knowledgeable individuals or alteration of individual preference can produce rapid changes in group formation and collective behaviour. For example, intensive fishing targeting the migratory species and also their preferred prey can reduce both terms to a point at which migration to the destination sites is suddenly stopped. The conceptual approaches represented by our modelling framework may therefore be able to explain large-scale changes in fish migration and spatial distribution.

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Evaluation of Ovaries in Patients with Polycystic Ovary Syndrome using Shear Wave Elastography

Current Medical Imaging Formerly Current Medical Imaging Reviews ◽

10.2174/1573405615666190114150538 ◽

2020 ◽

Vol 16 (5) ◽

pp. 578-583

Author(s):

Aysegul Altunkeser ◽

Zeynep Ozturk Inal ◽

Nahide Baran

Keyword(s):

Shear Wave ◽

Large Scale ◽

Polycystic Ovary ◽

Shear Wave Elastography ◽

Left Ovary ◽

Control Group ◽

Tissue Elasticity ◽

Group I ◽

Pcos Group ◽

The Right

Background: Shear wave electrography (SWE) is a novel non-invasive imaging technique which demonstrate tissue elasticity. Recent research evaluating the elasticity properties of normal and pathological tissues emphasize the diagnostic importance of this technique. Aims: Polycystic ovarian syndrome (PCOS), which is characterized by menstrual irregularity, hyperandrogenism, and polycystic overgrowth, may cause infertility. The aim of this study was to evaluate the elasticity of ovaries in patients with PCOS using SWE. Methods: 66 patients diagnosed with PCOS according to the Rotterdam criteria (PCOS = group I) and 72 patients with non-PCOS (Control = group II), were included in the study. Demographic and clinical characteristics of the participants were recorded. Ovarian elasticity was assessed in all patients with SWE, and speed values were obtained from the ovaries. The elasticity of the ovaries was compared between the two groups. Results: While there were statistically significant differences between the groups in body mass index (BMI), right and left ovarian volumes, luteinizing hormone and testosterone levels (p<0.05), no significant differences were found between groups I and II in the velocity (for the right ovary 3.89±1.81 vs. 2.93±0.72, p=0.301; for the left ovary 2.88±0.65 vs. 2.95±0.80, p=0.577) and elastography (for the right ovary 36.62±17.78 vs. 36.79±14.32, p=0.3952; for the left ovary 36.56±14.15 vs. 36.26±15.10, p=0.903) values, respectively. Conclusion: We could not obtain different velocity and elastography values from the ovaries of the patients with PCOS using SWE. Therefore, further large-scale studies are needed to elucidate this issue.

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Optimizing Manufacturing and Osseointegration of Ti6Al4V Implants through Precision Casting and Calcium and Phosphorus Ion Implantation? In Vivo Results of a Large-Scale Animal Trial

Materials ◽

10.3390/ma13071670 ◽

2020 ◽

Vol 13 (7) ◽

pp. 1670 ◽

Cited By ~ 2

Author(s):

Wölfle-Roos JV ◽

Katmer Amet B ◽

Fiedler J ◽

Michels H ◽

Kappelt G ◽

...

Keyword(s):

Ion Implantation ◽

Large Scale ◽

In Vivo Studies ◽

Control Group ◽

Implant Surface ◽

Precision Casting ◽

Pull Out ◽

Significant Difference ◽

Calcium And Phosphorus

Background: Uncemented implants are still associated with several major challenges, especially with regard to their manufacturing and their osseointegration. In this study, a novel manufacturing technique—an optimized form of precision casting—and a novel surface modification to promote osseointegration—calcium and phosphorus ion implantation into the implant surface—were tested in vivo. Methods: Cylindrical Ti6Al4V implants were inserted bilaterally into the tibia of 110 rats. We compared two generations of cast Ti6Al4V implants (CAST 1st GEN, n = 22, and CAST 2nd GEN, n = 22) as well as cast 2nd GEN Ti6Al4V implants with calcium (CAST + CA, n = 22) and phosphorus (CAST + P, n = 22) ion implantation to standard machined Ti6Al4V implants (control, n = 22). After 4 and 12 weeks, maximal pull-out force and bone-to-implant contact rate (BIC) were measured and compared between all five groups. Results: There was no significant difference between all five groups after 4 weeks or 12 weeks with regard to pull-out force (p > 0.05, Kruskal Wallis test). Histomorphometric analysis showed no significant difference of BIC after 4 weeks (p > 0.05, Kruskal–Wallis test), whereas there was a trend towards a higher BIC in the CAST + P group (54.8% ± 15.2%), especially compared to the control group (38.6% ± 12.8%) after 12 weeks (p = 0.053, Kruskal–Wallis test). Conclusion: In this study, we found no indication of inferiority of Ti6Al4V implants cast with the optimized centrifugal precision casting technique of the second generation compared to standard Ti6Al4V implants. As the employed manufacturing process holds considerable economic potential, mainly due to a significantly decreased material demand per implant by casting near net-shape instead of milling away most of the starting ingot, its application in manufacturing uncemented implants seems promising. However, no significant advantages of calcium or phosphorus ion implantation could be observed in this study. Due to the promising results of ion implantation in previous in vitro and in vivo studies, further in vivo studies with different ion implantation conditions should be considered.

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An Internet-based health gateway device for interactive communication and automatic data uploading: Clinical efficacy for type 2 diabetes in a multi-centre trial

Journal of Telemedicine and Telecare ◽

10.1177/1357633x16657500 ◽

2016 ◽

Vol 23 (6) ◽

pp. 595-604 ◽

Cited By ~ 15

Author(s):

Jae Hyoung Cho ◽

Hun-Sung Kim ◽

Seung Hyun Yoo ◽

Chang Hee Jung ◽

Woo Je Lee ◽

...

Keyword(s):

Adverse Events ◽

Healthcare System ◽

Glucose Control ◽

Large Scale ◽

Diabetes Management ◽

Intervention Group ◽

Diabetes Control ◽

Control Group ◽

Anthropometric Parameters ◽

Automatic Data

Introduction The aim of this study was to improve the quality of diabetes control and evaluate the efficacy of an Internet-based integrated healthcare system for diabetes management and safety. Methods We conducted a large-scale, multi-centre, randomized clinical trial involving 484 patients. Patients in the intervention group ( n = 244) were treated with the Internet-based system for six months, while the control group ( n = 240) received the usual outpatient management over the same period. HbA1c, blood chemistries, anthropometric parameters, and adverse events were assessed at the beginning of the study, after three months, and the end of the study. Results There were no initial significant differences between the groups with respect to demographics and clinical parameters. Upon six-month follow-up, HbA1c levels were significantly decreased from 7.86 ± 0.69% to 7.55 ± 0.86% within the intervention group ( p < 0.001) compared to 7.81 ± 0.66% to 7.70 ± 0.88% within the control group. Postprandial glucose reduction was predominant. A subgroup with baseline HbA1c higher than 8% and good compliance achieved a reduction of HbA1c by 0.8 ± 1.05%. Glucose control and waist circumference reduction were more effective in females and subjects older than 40 years of age. There were no adverse events associated with the intervention. Discussion This e-healthcare system was effective for glucose control and body composition improvement without associated adverse events in a multi-centre trial. This system may be effective in improving diabetes control in the general population.

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The effect of preloading statins prior to primary reperfusion on in-hospital mortality risk in a contemporary large-scale cohort of patients with ST-elevation myocardial infarction

European Heart Journal ◽

10.1093/ehjci/ehaa946.1464 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

R Fu ◽

C.X Song ◽

X.D Li ◽

Y.J Yang

Keyword(s):

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

Hospital Mortality ◽

Mortality Risk ◽

Large Scale ◽

Reperfusion Therapy ◽

St Elevation Myocardial Infarction ◽

Control Group ◽

Funding Source ◽

St Elevation

Abstract Background The benefit of statins in secondary prevention of patients stabilized after acute coronary syndrome (ACS) has been well established. However, the benefit of preloading statins, i.e. high-intensity statins prior to reperfusion therapy remains unclear. Most previous studies included all types of ACS patients, and subgroup analysis indicated the benefit of preloading statins was only seen in ST-elevation myocardial infarction (STEMI) patients who underwent percutaneous coronary intervention (PCI). However, the sample size of subgroup population was relatively small and such benefit requires further validation. Objective To investigate the effect of loading dose of statins before primary reperfusion on 30-mortality in patients with STEMI. Methods We enrolled patients in China Acute Myocardial Infarction (CAMI) registry from January 2013 to September 2014. CAMI registry was a prospective multicenter registry of patients with acute acute myocardial infarction in China. Patients were divided into two groups according to statins usage: preloading group and control group. Patients in preloading group received loading does of statins before primary reperfusion and during hospitalization. Patients in control group did not receive statins during hospitalization or at discharge. Primary outcome was in-hospital mortality. Baseline characteristics, angiographic characteristics and outcome were compared between groups. Propensity score (PS) matching was used to mitigate baseline differences between groups and examine the association between preloading statins on in-hospital mortality risk. The following variables were used to establish PS matching score: age, sex, classification of hospitals, clinical presentation (heart failure at presentation, cardiac shock, cardiac arrest, Killip classification), hypertension, diabetes, prior angina, prior myocardial infarction history, prior stroke, initial treatment. Results A total of 1169 patients were enrolled in control group and 6795 in preloading group. A total of 833 patients (334 in control group and 499 in preloading group) died during hospitalization. Compared with control group, preloading group were younger, more likely to be male and present with Killip I classification. The proportion of hypertension and diabetes were higher in preloading group. After PS matching, all the variables used to generate PS score were well balanced. In the PS-matched cohort, 30-day mortality risk was 26.3% (292/1112) in the control group and 11.9% (132/1112) in the preloading group (p<0.0001). Conclusions The current study found preloading statins treatment prior to reperfusion therapy reduced in-hospital mortality risk in a large-scale contemporary cohort of patients with STEMI. Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): Chinese Academy of Medical Sciences

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Comparison of the curative effect and prognosis of stereotactic drainage and conservative treatment for moderate and small basal ganglia haemorrhage

BMC Neurology ◽

10.1186/s12883-021-02293-7 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Xin Huang ◽

Lai Jiang ◽

Shaojun Chen ◽

Gang Li ◽

Wanxi Pan ◽

...

Keyword(s):

Basal Ganglia ◽

Large Scale ◽

Neurological Function ◽

Lower Limbs ◽

Control Group ◽

Roc Curve Analysis ◽

Curative Effect ◽

Nihss Score ◽

Haematoma Volume ◽

Experimental Group

Abstract Background Minimally invasive surgery has achieved good results in the treatment of cerebral haemorrhage.However, no large-scale clinical study has demonstrated that surgical treatment of cerebral haemorrhages less than 30 ml can improve the curative effect. Our study explored the efficacy and complication of stereotactic drainage based on the amount of cerebral hemorrhage (15-30 ml) in hypertensive basal ganglia. Method Sixty patients with hypertensive basal ganglia haemorrhages were divided into a control group and an experimental group with 30 patients in each group. Patients in the control group were treated conservatively. In contrast, those in the experimental group received stereotactic drainage, and urokinase was injected into the haematoma cavity after the operation. The haematoma volume at admission and 1, 3, 7 and 30 days after treatment and National Institute of Health stroke scale(NIHSS) score data were recorded. Complications after treatment in the two groups of data were compared and analysed. Result No significant differences in age, sex, time of treatment after onset, admission blood pressure, admission haematoma volume or admission NIHSS score were noted between these two groups (P > 0.05). After treatment, significant differences in haematoma volume were noted between the two groups on the 1st, 3rd, 7th and 30th days after treatment (P < 0.05). The amount of hematoma of patients in the experimental group was significantly reduced compared with that in the control group, and the NIHSS scores were significantly different on the 3rd, 7th and 30th days after treatment. The neurological deficit scores of patients in the experimental group were significantly reduced compared with those in the control group, and the incidence of pulmonary infection and venous thrombosis in the lower limbs of patients in the experimental group were significantly reduced (P < 0.05). ROC curve analysis showed that stereotactic drainage affected the early neurological function of patients with small and medium basal ganglia haemorrhages. Conclusion For patients with small and medium basal ganglia haemorrhages, stereotactic drainage can be used due to the faster drainage speed of haematomas after operation, which is beneficial to the recovery of neurological function and reduce complications.

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EEG Data Quality: Determinants and Impact in a Multicenter Study of Children, Adolescents, and Adults with Attention-Deficit/Hyperactivity Disorder (ADHD)

Brain Sciences ◽

10.3390/brainsci11020214 ◽

2021 ◽

Vol 11 (2) ◽

pp. 214

Author(s):

Anna Kaiser ◽

Pascal-M. Aggensteiner ◽

Martin Holtmann ◽

Andreas Fallgatter ◽

Marcel Romanos ◽

...

Keyword(s):

Data Quality ◽

Large Scale ◽

Linear Models ◽

Spectral Power ◽

Control Group ◽

Continuous Performance Task ◽

Related Data ◽

Eyes Closed ◽

Eeg Data ◽

Eyes Open

Electroencephalography (EEG) represents a widely established method for assessing altered and typically developing brain function. However, systematic studies on EEG data quality, its correlates, and consequences are scarce. To address this research gap, the current study focused on the percentage of artifact-free segments after standard EEG pre-processing as a data quality index. We analyzed participant-related and methodological influences, and validity by replicating landmark EEG effects. Further, effects of data quality on spectral power analyses beyond participant-related characteristics were explored. EEG data from a multicenter ADHD-cohort (age range 6 to 45 years), and a non-ADHD school-age control group were analyzed (ntotal = 305). Resting-state data during eyes open, and eyes closed conditions, and task-related data during a cued Continuous Performance Task (CPT) were collected. After pre-processing, general linear models, and stepwise regression models were fitted to the data. We found that EEG data quality was strongly related to demographic characteristics, but not to methodological factors. We were able to replicate maturational, task, and ADHD effects reported in the EEG literature, establishing a link with EEG-landmark effects. Furthermore, we showed that poor data quality significantly increases spectral power beyond effects of maturation and symptom severity. Taken together, the current results indicate that with a careful design and systematic quality control, informative large-scale multicenter trials characterizing neurophysiological mechanisms in neurodevelopmental disorders across the lifespan are feasible. Nevertheless, results are restricted to the limitations reported. Future work will clarify predictive value.

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The utility of self-rated health in population surveys: the role of bodyweight

Population Health Metrics ◽

10.1186/s12963-021-00255-2 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Robert Bozick

Keyword(s):

Treatment Group ◽

Large Scale ◽

Well Being ◽

Control Group ◽

Self Rated Health ◽

Risk Of Mortality ◽

Highly Sensitive ◽

The Usa ◽

Group Members ◽

Nationally Representative

Abstract Background Self-rated health (SRH) is one of the most commonly used summary measures of overall health and well-being available to population scientists due to its ease of administration in large-scale surveys and to its efficacy in predicting mortality. This paper assesses the extent to which SRH is affected by its placement before or after questions about bodyweight on a survey, and whether differences in placement on the questionnaire affects SRH’s predictive validity. Methods I assessed the validity of SRH in predicting the risk of mortality by comparing outcomes of sample members who were asked to rate their health before reporting on their bodyweight (the control group) and sample members who were asked to rate their health after reporting on their bodyweight (the treatment group). Both the control and treatment group were randomly assigned via an experiment administered as a module in a nationally representative sample of adults in the USA in 2019 (N = 2523). Results The odds of reporting a more favorable appraisal of health are 30% lower for sample members who were in the treatment group when compared with the control group. Additionally, the SRH of treatment group members is significantly associated with their risk of mortality, while the SRH of control group members is not. Conclusion The findings from this study suggest that for researchers to maximize the utility of SRH, closer attention needs to be paid to the context of the survey within which it asked. SRH is highly sensitive to the questions that precede it, and this sensitivity may in turn mischaracterize the true health of the population that the survey is intending to measure.

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Hair Follicle Melanogenesis Reflected in Hair Pigmentation as a Developmental Factor in Alopecia Areata

Skin Appendage Disorders ◽

10.1159/000516301 ◽

2021 ◽

pp. 1-3

Author(s):

Margit Juhasz ◽

Rosalynn R.Z. Conic ◽

Natasha Atanaskova Mesinkovska

Keyword(s):

Hair Follicle ◽

Alopecia Areata ◽

Large Scale ◽

Medical Center ◽

Control Group ◽

Hair Color ◽

Natural Hair ◽

Hair Pigmentation ◽

Developmental Factor ◽

Record Review

The mechanism of alopecia areata (AA) is not well-elucidated, and hair follicle melanogenesis pathways are implicated as possible sources for autoantigens. After a retrospective medical record review at a single tertiary medical center, the hair color of 112 AA patients were identified and compared to a control group of 104 androgenetic alopecia patients. There were no statistically significant differences in the natural hair color prevalence between the 2 groups (<i>p</i> = 0.164), and hair color was not a predictor of the alopecia type. Our results suggest hair pigmentation, determined by the eumelanin-to-pheomelanin ratio, is not a positive risk factor for AA development. We hope that our study will encourage multiple large-scale, collaborative, retrospective medical reviews to determine if our results are reproducible in diverse patient populations.

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Flipping the Script: Measuring Both Performance Validity and Cognitive Ability with the Forced Choice Recognition Trial of the RCFT

Perceptual and Motor Skills ◽

10.1177/00315125211019704 ◽

2021 ◽

pp. 003151252110197

Author(s):

Kaitlyn Abeare ◽

Kristoffer Romero ◽

Laura Cutler ◽

Christina D. Sirianni ◽

Laszlo A. Erdodi

Keyword(s):

Cognitive Ability ◽

Verbal Memory ◽

Visual Memory ◽

Large Scale ◽

Clinical Sample ◽

Neuropsychological Test ◽

Forced Choice ◽

Control Group ◽

Performance Validity ◽

Two Samples

In this study we attempted to replicate the classification accuracy of the newly introduced Forced Choice Recognition trial (FCR) of the Rey Complex Figure Test (RCFT) in a clinical sample. We administered the RCFT FCR and the earlier Yes/No Recognition trial from the RCFT to 52 clinically referred patients as part of a comprehensive neuropsychological test battery and incentivized a separate control group of 83 university students to perform well on these measures. We then computed the classification accuracies of both measures against criterion performance validity tests (PVTs) and compared results between the two samples. At previously published validity cutoffs (≤16 & ≤17), the RCFT FCR remained specific (.84–1.00) to psychometrically defined non-credible responding. Simultaneously, the RCFT FCR was more sensitive to examinees’ natural variability in visual-perceptual and verbal memory skills than the Yes/No Recognition trial. Even after being reduced to a seven-point scale (18-24) by the validity cutoffs, both RCFT recognition scores continued to provide clinically useful information on visual memory. This is the first study to validate the RCFT FCR as a PVT in a clinical sample. Our data also support its use for measuring cognitive ability. Replication studies with more diverse samples and different criterion measures are still needed before large-scale clinical application of this scale.

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Statistical methods for unidirectional switch designs: Past, present, and future

Statistical Methods in Medical Research ◽

10.1177/0962280216689280 ◽

2017 ◽

Vol 27 (9) ◽

pp. 2872-2882 ◽

Cited By ~ 1

Author(s):

Zhuozhao Zhan ◽

Geertruida H de Bock ◽

Edwin R van den Heuvel

Keyword(s):

Statistical Methods ◽

Large Scale ◽

Sample Size Calculation ◽

Complex Interventions ◽

New Drugs ◽

Control Treatment ◽

Future Research ◽

Control Group ◽

Unified Framework ◽

New Treatment

Clinical trials may apply or use a sequential introduction of a new treatment to determine its efficacy or effectiveness with respect to a control treatment. The reasons for choosing a particular switch design have different origins. For instance, they may be implemented for ethical or logistic reasons or for studying disease-modifying effects. Large-scale pragmatic trials with complex interventions often use stepped wedge designs (SWDs), where all participants start at the control group, and during the trial, the control treatment is switched to the new intervention at different moments. They typically use cross-sectional data and cluster randomization. On the other hand, new drugs for inhibition of cognitive decline in Alzheimer’s or Parkinson’s disease typically use delayed start designs (DSDs). Here, participants start in a parallel group design and at a certain moment in the trial, (part of) the control group switches to the new treatment. The studies are longitudinal in nature, and individuals are being randomized. Statistical methods for these unidirectional switch designs (USD) are quite complex and incomparable, and they have been developed by various authors under different terminologies, model specifications, and assumptions. This imposes unnecessary barriers for researchers to compare results or choose the most appropriate method for their own needs. This paper provides an overview of past and current statistical developments for the USDs (SWD and DSD). All designs are formulated in a unified framework of treatment patterns to make comparisons between switch designs easier. The focus is primarily on statistical models, methods of estimation, sample size calculation, and optimal designs for estimation of the treatment effect. Other relevant open issues are being discussed as well to provide suggestions for future research in USDs.

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