108 research outputs found
Correlations between synapses in pairs of neurons slow down dynamics in randomly connected neural networks
Networks of randomly connected neurons are among the most popular models in
theoretical neuroscience. The connectivity between neurons in the cortex is
however not fully random, the simplest and most prominent deviation from
randomness found in experimental data being the overrepresentation of
bidirectional connections among pyramidal cells. Using numerical and analytical
methods, we investigated the effects of partially symmetric connectivity on
dynamics in networks of rate units. We considered the two dynamical regimes
exhibited by random neural networks: the weak-coupling regime, where the firing
activity decays to a single fixed point unless the network is stimulated, and
the strong-coupling or chaotic regime, characterized by internally generated
fluctuating firing rates. In the weak-coupling regime, we computed analytically
for an arbitrary degree of symmetry the auto-correlation of network activity in
presence of external noise. In the chaotic regime, we performed simulations to
determine the timescale of the intrinsic fluctuations. In both cases, symmetry
increases the characteristic asymptotic decay time of the autocorrelation
function and therefore slows down the dynamics in the network.Comment: 17 pages, 7 figure
Hemoglobin spectra affect measurement of tissue oxygen saturation
Tissue oxygen saturation (StO2) is a valuable clinical parameter e.g. for intensive care applications or monitoring during surgery. Studies showed that near-infrared spectroscopy (NIRS) based tissue oximeters of different brands give systematically different readings of StO2. Usually these readings are linearly correlated and therefore StO2 readings from one instrument can easily be converted to those of another instrument. However, it is interesting to understand why there is this difference. One reason may be that different brands employ different spectra of hemoglobin. The aim here was to investigate how these different absorption spectra of hemoglobin affect the StO2 readings. Therefore, we performed changes in StO2 in a phantom experiment with real human hemoglobin at three different concentrations (26.5, 45 and 70 ÎŒM): desaturation by yeast consuming the oxygen and re-saturation by bubbling oxygen gas. The partial pressure of O2 in the liquid changed from at least 10 kPa to ~0 kPa and ISS OxiplexTS, a frequency-domain NIRS instrument, was used to monitor changes of StO2. When we employed two different absorption spectra for hemoglobin, StO2 values were comparable in the normal physiological range. However, particularly at high and low StO2 values, a difference of >6% between these two spectra were noticed. Such a difference of >6% is substantial and relevant for medical applications. This may partly explain why different brands of NIRS instruments provide different StO2 readings. The hemoglobin spectra are therefore a factor to be considered for future developments and applications of NIRS oximeters
In Vitro Comparisons of Near-Infrared Spectroscopy Oximeters: Impact of Slow Changes in Scattering of Liquid Phantoms
Several cerebral oximeters based on near-infrared spectroscopy (NIRS) are commercially available that determine tissue oxygen saturation (StO). One problem is an inconsistency of StO readings between different brands of instruments. Liquid blood phantoms mimicking optical properties of the neonatal head enable quantitative device comparisons. However, occasionally, the reduced scattering coefficient (ÎŒ') of these phantoms decreases over time. AIM To investigate whether this decrease in ÎŒ' affects the validity of comparison of these devices. StO was measured by several NIRS oximeters simultaneously on a phantom, which exhibited a particularly strong decrease in ÎŒ'. We found that a decrease in ÎŒ' by â€16% from baseline led to deviations in StO of â€3%
Absorption spectra of early stool from preterm infants need to be considered in abdominal NIRS oximetry
Necrotizing enterocolitis (NEC) is the most common gastrointestinal emergency of the preterm infant. Low abdominal tissue oxygen saturation (StO2) measured by near-infrared spectroscopy (NIRS) oximetry may be an early sign of NEC relevant for treating or even preventing NEC. However, current commercial NIRS oximeters provide inaccurate StO2 readings because they neglect stool as an abdominal absorber. To tackle this problem, we determined the optical properties of faeces of preterm infants to enable a correct abdominal StO2 measurement. In 25 preterm born infants (median age 31 0/7 ± 2 1/7 weeks, weight 1478 ± 511 g), we measured their first five stool probes with a VIS/NIR spectrometer and calculated the optical properties using the Inverse Adding Doubling (IAD) method. We obtained two absorption spectra representing meconium and transitional stool. Probabilistic cluster analysis correctly classified 96 out of 107 stool probes. The faeces spectra need to be considered to enable correct abdominal StO2 measurements with NIRS oximetry
INTEGRATION OF COMPLEMENTARY BIOMARKERS IN PATIENTS WITH FIRST EPISODE PSYCHOSIS: RESEARCH PROTOCOL OF A PROSPECTIVE FOLLOW UP STUDY
In this project, we recruited a sample of 150 patients with first episode of psychosis with schizophrenia features (FEP) and 100 healthy controls. We assessed the differences between these two groups, as well as the changes between the acute phase of illness and subsequent remission among patients over 18-month longitudinal follow-up. The assessments were divided into four work packages (WP): WP1- psychopathological status, neurocognitive functioning and emotional recognition; WP2- stress response measured by saliva cortisol during a stress paradigm; cerebral blood perfusion in the resting state (with single photon emission computed tomography (SPECT) and during activation paradigm (with Transcranial Ultrasonography Doppler (TCD); WP3-post mortem analysis in histologically prepared human cortical tissue of post mortem samples of subjects with schizophrenia in the region that synaptic alteration was suggested by WP1 and WP2; WP4- pharmacogenetic analysis (single gene polymorphisms and genome wide association study (GWAS). We expect that the analysis of these data will identify a set of markers that differentiate healthy controls from patients with FEP, and serve as an additional diagnostic tool in the first episode of psychosis, and prediction tool which can be then used to help tailoring individualized treatment options. In this paper, we describe the project protocol including aims and methods and provide a brief description of planned post mortem studies and pharmacogenetic analysis
Socioeconomic differences in food habits among 6- to 9-year-old children from 23 countries-WHO European Childhood Obesity Surveillance Initiative (COSI 2015/2017)
Background: Socioeconomic differences in children's food habits are a key public health concern. In order to inform policy makers, cross-country surveillance studies of dietary patterns across socioeconomic groups are required. The purpose of this study was to examine associations between socioeconomic status (SES) and children's food habits.
Methods: The study was based on nationally representative data from children aged 6-9 years (n = 129,164) in 23 countries in the World Health Organization (WHO) European Region. Multivariate multilevel analyses were used to explore associations between children's food habits (consumption of fruit, vegetables, and sugar-containing soft drinks) and parental education, perceived family wealth and parental employment status.
Results: Overall, the present study suggests that unhealthy food habits are associated with lower SES, particularly as assessed by parental education and family perceived wealth, but not parental employment status. We found cross-national and regional variation in associations between SES and food habits and differences in the extent to which the respective indicators of SES were related to children's diet.
Conclusion: Socioeconomic differences in children's food habits exist in the majority of European and Asian countries examined in this study. The results are of relevance when addressing strategies, policy actions, and interventions targeting social inequalities in children's diets.The authors gratefully acknowledge support from a grant from the
Russian Government in the context of the WHO European Office for
the Prevention and Control of NCDs.
Data collection in the countries was made possible through
funding from Albania: WHO through the Joint Programme on
Children, Food Security and Nutrition âReducing Malnutrition in
Children,â funded by the Millennium Development Goals Achievement Fund, and the Institute of Public Health; Bulgaria: Ministry of
Health, National Center of Public Health and Analyses, WHO
Regional Office for Europe; Croatia: Ministry of Health, Croatian
Institute of Public Health and WHO Regional Office for Europe;
Czechia: Ministry of Health of the Czech Republic, grant nr. AZV
MZÄR 17-31670 A and MZÄâVO EĂ 00023761; Denmark: Danish
Ministry of Health; Georgia: WHO; Ireland: Health Service Executive; Italy: Ministry of Health and Italian National Institute of Health;
Kazakhstan: Ministry of Health of the Republic of Kazakhstan and
WHO Country Office; Kyrgyzstan: World Health Organization;
Latvia: Ministry of Health, Centre for Disease Prevention and
Control; Lithuania: Science Foundation of Lithuanian University of
Health Sciences and Lithuanian Science Council and WHO; Malta:
Ministry of Health; Montenegro: WHO and Institute of Public
Health of Montenegro; Norway: Ministry of Health and Norwegian
Institute of Public Health; Poland: National Health Programme, Ministry of Health; Portugal: Ministry of Health Institutions, the
National Institute of Health, Directorate General of Health, Regional
Health Directorates and the kind technical support from the
Center for Studies and Research on Social Dynamics and Health
(CEIDSS); Romania: Ministry of Health; Russian Federation: WHO;
San Marino: Health Ministry, Educational Ministry; Serbia: This
study was supported by the World Health Organization (Ref. File
2015-540940); Spain: Spanish Agency for Food Safety and Nutrition
(AESAN); Tajikistan: WHO Country Office in Tajikistan and Ministry of Health and Social Protection; Turkmenistan: WHO Country
Office in Turkmenistan and Ministry of Health; Turkey: Turkish Ministry of Health and World Bank.
The CO-CREATE project has received funding from the European
Union's Horizon 2020 research and innovation program under grant
agreement No. 774210.info:eu-repo/semantics/publishedVersio
Urban and rural differences in frequency of fruit, vegetable, and soft drink consumption among 6â9âyearâold children from 19 countries from the WHO European region
In order to address the paucity of evidence on the association between childhood eating habits and urbanization, this cross-sectional study describes urbanârural differences in frequency of fruit, vegetable, and soft drink consumption in 123,100 children aged 6â9 years from 19 countries participating in the fourth round (2015-2017) of the WHO European Childhood Obesity Surveillance Initiative (COSI). Children's parents/caregivers completed food-frequency questionnaires. A multivariate multilevel logistic regression analysis was performed and revealed wide variability among countries and within macroregions for all indicators. The percentage of children attending rural schools ranged from 3% in Turkey to 70% in Turkmenistan. The prevalence of less healthy eating habits was high, with between 30â80% and 30â90% children not eating fruit or vegetables daily, respectively, and up to 45% consuming soft drinks on >3 days a week. For less than one third of the countries, children attending rural schools had higher odds (OR-range: 1.1â2.1) for not eating fruit or vegetables daily or consuming soft drinks >3 days a week compared to children attending urban schools. For the remainder of the countries no significant associations were observed. Both population-based interventions and policy strategies are necessary to improve access to healthy foods and increase healthy eating behaviors among children.The authors gratefully acknowledge support from a grant from the
Russian Government in the context of the WHO European Office for
the Prevention and Control of NCDs.
Data collection in the countries was made possible through
funding from Albania: WHO through the Joint Programme on
Children, Food Security and Nutrition âReducing Malnutrition in
Children,â funded by the Millennium Development Goals Achievement Fund, and the Institute of Public Health; Austria: Federal Ministry of Social Affairs, Health, Care and Consumer Protection, Republic
of Austria; Bulgaria: Ministry of Health, National Center of Public
Health and Analyses, WHO Regional Office for Europe; Croatia: Ministry of Health, Croatian Institute of Public Health and WHO
Regional Office for Europe; Ministry of Health of the Czech Republic,
grant nr. AZV MZÄR 17-31670 A and MZÄRâRVO EĂ 00023761;
Denmark: Danish Ministry of Health; Estonia: Ministry of Social
Affairs, Ministry of Education and Research (IUT 42-2), WHO Country
Office, and National Institute for Health Development; Georgia:
WHO; Ireland: Health Service Executive; Italy: Ministry of Health and
Italian National Institute of Health; Kazakhstan: Ministry of Health of
the Republic of Kazakhstan and WHO Country Office; Kyrgyzstan:
World Health Organization; Latvia: Ministry of Health, Centre for
Disease Prevention and Control; Lithuania: Science Foundation of
Lithuanian University of Health Sciences and Lithuanian Science
Council and WHO; Malta: Ministry of Health; Montenegro: WHO and
Institute of Public Health of Montenegro; North Macedonia: COSI in
North Macedonia is funded by the Government of North Macedonia
through National Annual Program of Public Health and implemented
by the Institute of Public Health and Centers of Public Health in the
country. WHO country office provides support for training and data
management; Norway: Ministry of Health and Norwegian Institute of
Public Health; Poland: National Health Programme, Ministry of
Health; Portugal: Ministry of Health Institutions, the National Institute
of Health, Directorate General of Health, Regional Health Directorates and the kind technical support from the Center for Studies and
Research on Social Dynamics and Health (CEIDSS); Romania: Ministry
of Health; Serbia: This study was supported by the World Health
Organization (Ref. File 2015-540940); Slovakia: Biennial Collaborative
Agreement between WHO Regional Office for Europe and Ministry
of Health SR; Spain: Spanish Agency for Food Safety and Nutrition
(AESAN); Tajikistan: WHO Country Office in Tajikistan and Ministry
of Health and Social Protection; Turkmenistan: WHO Country Office
in Turkmenistan and Ministry of Health; Turkey: Turkish Ministry of
Health and World Bank.info:eu-repo/semantics/publishedVersio
Socioeconomic disparities in physical activity, sedentary behavior and sleep patterns among 6- to 9-year-old children from 24 countries in the WHO European region
Physical activity, sedentary behavior, and sleep are important predictors of children's health. This paper aimed to investigate socioeconomic disparities in physical activity, sedentary behavior, and sleep across the WHO European region. This cross-sectional study used data on 124,700 children aged 6 to 9 years from 24 countries participating in the WHO European Childhood Obesity Surveillance Initiative between 2015 and 2017. Socioeconomic status (SES) was measured through parental education, parental employment status, and family perceived wealth. Overall, results showed different patterns in socioeconomic disparities in children's movement behaviors across countries. In general, high SES children were more likely to use motorized transportation. Low SES children were less likely to participate in sports clubs and more likely to have more than 2 h/day of screen time. Children with low parental education had a 2.24 [95% CI 1.94-2.58] times higher risk of practising sports for less than 2 h/week. In the pooled analysis, SES was not significantly related to active play. The relationship between SES and sleep varied by the SES indicator used. Importantly, results showed that low SES is not always associated with a higher prevalence of "less healthy" behaviors. There is a great diversity in SES patterns across countries which supports the need for country-specific, targeted public health interventions.The authors gratefully acknowledge support from a grant from the
Russian Government in the context of the WHO European Office for
the Prevention and Control of NCDs. Data collection in the countries
was made possible through funding from: Croatia: Ministry of Health,
Croatian Institute of Public Health and WHO Regional Office for
Europe. Albania: World Health Organization (WHO) Country Office
Albania and the WHO Regional Office for Europe. Bulgaria: WHO
Regional Office for Europe. Czech Republic: Ministry of Health of the
Czech Republic, grant nr. AZV MZÄR 17-31670 A and MZÄRâRVO
EĂ 00023761. Denmark: The Danish Ministry of Health. France:
Santé publique France, the French Agency for Public Health. Georgia:
WHO. Ireland: Health Service Executive. Italy: Italian Ministry of
Health; Italian National Institute of Health (Istituto Superiore di
SanitĂ ). Kazakhstan: the Ministry of Health of the Republic of
Kazakhstan within the scientific and technical program. Kyrgyzstan:
World Health Organization. Latvia: Centre for Disease Prevention and
Control, Ministry of Health, Latvia. Lithuania: Science Foundation of
Lithuanian University of Health Sciences and Lithuanian Science
Council and WHO. Malta: Ministry of Health. Montenegro: WHO and
Institute of Public Health of Montenegro. Poland: National Health
Programme, Ministry of Health. Portugal: Ministry of Health Institutions, the National Institute of Health, Directorate General of Health,
Regional Health Directorates and the kind technical support from the
Center for Studies and Research on Social Dynamics and Health
(CEIDSS). Romania: Ministry of Health. Russian Federation: WHO. San Marino: Health Ministry. Spain: the Spanish Agency for Food
Safety & Nutrition. Tajikistan: WHO Country Office in Tajikistan and
Ministry of Health and Social Protection; Turkmenistan: WHO
Country Office in Turkmenistan and Ministry of Health. Turkey:
Turkish Ministry of Health and World Bank. Austria: Federal Ministry
of Labor, Social Affairs, Health and Consumer Protection of Austria.info:eu-repo/semantics/publishedVersio
Parental Perceptions of Childrenâs Weight Status in 22 Countries: The WHO European Childhood Obesity Surveillance Initiative: COSI 2015/2017
Introduction: Parents can act as important agents of change
and support for healthy childhood growth and development. Studies have found that parents may not be able to
accurately perceive their childâs weight status. The purpose
of this study was to measure parental perceptions of their
childâs weight status and to identify predictors of potential
parental misperceptions. Methods: We used data from the
World Health Organization (WHO) European Childhood
Obesity Surveillance Initiative and 22 countries. Parents
were asked to identify their perceptions of their childrenâs
weight status as âunderweight,â ânormal weight,â âa little
overweight,â or âextremely overweight.â We categorized
childrenâs (6â9 years; n = 124,296) body mass index (BMI) as
BMI-for-age Z-scores based on the 2007 WHO-recommended growth references. For each country included in the analysis and pooled estimates (country level), we calculated the
distribution of children according to the WHO weight status
classification, distribution by parental perception of childâs
weight status, percentages of accurate, overestimating, or
underestimating perceptions, misclassification levels, and
predictors of parental misperceptions using a multilevel logistic regression analysis that included only children with
overweight (including obesity). Statistical analyses were performed using Stata version 15 1. Results: Overall, 64.1% of
parents categorized their childâs weight status accurately
relative to the WHO growth charts. However, parents were
more likely to underestimate their childâs weight if the child
had overweight (82.3%) or obesity (93.8%). Parents were
more likely to underestimate their childâs weight if the child
was male (adjusted OR [adjOR]: 1.41; 95% confidence intervals [CI]: 1.28â1.55); the parent had a lower educational level
(adjOR: 1.41; 95% CI: 1.26â1.57); the father was asked rather
than the mother (adjOR: 1.14; 95% CI: 0.98â1.33); and the
family lived in a rural area (adjOR: 1.10; 95% CI: 0.99â1.24).
Overall, parentsâ BMI was not strongly associated with the
underestimation of childrenâs weight status, but there was a
stronger association in some countries. Discussion/Conclusion: Our study supplements the current literature on factors
that influence parental perceptions of their childâs weight
status. Public health interventions aimed at promoting
healthy childhood growth and development should consider parentsâ knowledge and perceptions, as well as the sociocultural contexts in which children and families live.The authors gratefully acknowledge support from a grant from
the Russian Government in the context of the WHO European Office for the Prevention and Control of NCDs. Data collection in the
countries was made possible through funding by: Albania: World
Health Organization through the Joint Programme on Children,
Food Security and Nutrition âReducing Malnutrition in Children,â funded by the Millennium Development Goals Achievement Fund, and the Institute of Public Health; Bulgaria: Ministry
of Health, National Center of Public Health and Analyses, World
Health Organization Regional Office for Europe; Croatia: Ministry of Health, Croatian Institute of Public Health and World
Health Organization Regional Office for Europe; Czechia: Grants
AZV MZÄR 17-31670 A and MZÄR â RVO EĂ 00023761; Denmark: Danish Ministry of Health; France: French Public Health
Agency; Georgia: World Health Organization; Ireland: Health
Service Executive; Italy: Ministry of Health; Istituto Superiore di
sanitĂ (National Institute of Health); Kazakhstan: Ministry of Health of the Republic of Kazakhstan and World Health Organization Country Office; Latvia: n/a; Lithuania: Science Foundation of
Lithuanian University of Health Sciences and Lithuanian Science
Council and World Health Organization; Malta: Ministry of
Health; Montenegro: World Health Organization and Institute of
Public Health of Montenegro; Poland: National Health Programme, Ministry of Health; Portugal: Ministry of Health Institutions, the National Institute of Health, Directorate General of
Health, Regional Health Directorates and the kind technical support of Center for Studies and Research on Social Dynamics and
Health (CEIDSS); Romania: Ministry of Health; Russia (Moscow): n/a; San Marino: Health Ministry; Educational Ministry; Social Security Institute; the Health Authority; Spain: Spanish Agency for Food Safety and Nutrition (AESAN); Tajikistan: World
Health Organization Country Office in Tajikistan and Ministry of
Health and Social Protection; and Turkmenistan: World Health
Organization Country Office in Turkmenistan and Ministry of
Health. The authors alone are responsible for the views expressed
in this article and they do not necessarily represent the views, decisions, or policies of the institutions with which they are affiliated.info:eu-repo/semantics/publishedVersio
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