431 research outputs found
A Machine Learning Approach to Measure and Monitor Physical Activity in Children to Help Fight Overweight and Obesity
Physical Activity is important for maintaining healthy lifestyles. Recommendations for physical activity levels are issued by most governments as part of public health measures. As such, reliable measurement of physical activity for regulatory purposes is vital. This has lead research to explore standards for achieving this using wearable technology and artificial neural networks that produce classifications for specific physical activity events. Applied from a very early age, the ubiquitous capture of physical activity data using mobile and wearable technology may help us to understand how we can combat childhood obesity and the impact that this has in later life. A supervised machine learning approach is adopted in this paper that utilizes data obtained from accelerometer sensors worn by children in free-living environments. The paper presents a set of activities and features suitable for measuring physical activity and evaluates the use of a Multilayer Perceptron neural network to classify physical activities by activity type. A rigorous reproducible data science methodology is presented for subsequent use in physical activity research. Our results show that it was possible to obtain an overall accuracy of 96 % with 95 % for sensitivity, 99 % for specificity and a kappa value of 94 % when three and four feature combinations were used
Antioxidant pathways are up-regulated during biological nitrogen fixation to prevent ROS-induced nitrogenase inhibition in Gluconacetobacter diazotrophicus
Gluconacetobacter diazotrophicus, an endophyte isolated from sugarcane, is a strict aerobe that fixates N2. This process is catalyzed by nitrogenase and requires copious amounts of ATP. Nitrogenase activity is extremely sensitive to inhibition by oxygen and reactive oxygen species (ROS). However, the elevated oxidative metabolic rates required to sustain biological nitrogen fixation (BNF) may favor an increased production of ROS. Here, we explored this paradox and observed that ROS levels are, in fact, decreased in nitrogen-fixing cells due to the up-regulation of transcript levels of six ROS-detoxifying genes. A cluster analyses based on common expression patterns revealed the existence of a stable cluster with 99.8% similarity made up of the genes encoding the Îą-subunit of nitrogenase MoâFe protein (nifD), superoxide dismutase (sodA) and catalase type E (katE). Finally, nitrogenase activity was inhibited in a dose-dependent manner by paraquat, a redox cycler that increases cellular ROS levels. Our data revealed that ROS can strongly inhibit nitrogenase activity, and G. diazotrophicus alters its redox metabolism during BNF by increasing antioxidant transcript levels resulting in a lower ROS generation. We suggest that careful controlled ROS production during this critical phase is an adaptive mechanism to allow nitrogen fixation
The influence of socio-economic and surveillance characteristics on breast cancer survival: a French population-based study
Survival data on female invasive breast cancer with 9-year follow-up from five French cancer registries were analysed by logistic regression for prognostic factors of cancer stage. The KaplanâMeier method and log-rank test were used to estimate and compare the overall survival probability at 5 and 7 years, and at the endpoint. The Cox regression model was used for multivariate analysis. County of residence, age group, occupational status, mammographic surveillance, gynaecological prevention consultations and the diagnosis mammography, whether within a screening framework or not, were independent prognostic factors of survival. Moreover, for the same age group, and only for cancers T2 and/or N+ (whether 1, 2 or 3) and M0, the prognosis was significantly better when the diagnosis mammography was done within the framework of screening. Socio-economic and surveillance characteristics are independent prognostic factors of both breast cancer stage at diagnosis and of survival. Screening mammography is an independent prognostic factor of survival
Genetic Manipulation of Schistosoma haematobium, the Neglected Schistosome
More people are infected with Schistosoma haematobium than other major human schistosomes yet it has been less studied because of difficulty in maintaining the life cycle in the laboratory. S. haematobium might be considered the âneglected schistosomeâ since minimal information on the genome and proteome of S. haematobium is available, in marked contrast to the other major schistosomes. In this report we describe tools and protocols to investigate the genome and genetics of this neglected schistosome. We cultured developmental stages of S. haematobium, and investigated the utility of introducing gene probes into the parasites to silence two model genes. One of these, firefly luciferase, was a reporter gene whereas the second was a schistosome gene encoding a surface protein, termed Sh-tsp-2. We observed that both genes could be silenced â a phenomenon known as experimental RNA interference (RNAi). These findings indicated that the genome of S. haematobium will be amenable to genetic manipulation investigations designed to determine the function and importance of genes of this schistosome and to investigate for novel anti-parasite treatments
Shorter spontaneous fixation durations in infants with later emerging autism
Little is known about how spontaneous attentional deployment differs on a millisecond-level scale in the early development of autism spectrum disorders (ASD). We measured fine-grained eye movement patterns in 6-to 9-month-old infants at high or low familial risk (HR/LR) of ASD while they viewed static images. We observed shorter fixation durations (i.e. the time interval between saccades) in HR than LR infants. Preliminary analyses indicate that these results were replicated in a second cohort of infants. Fixation durations were shortest in those infants who went on to receive an ASD diagnosis at 36 months. While these findings demonstrate early-developing atypicality in fine-grained measures of attentional deployment early in the etiology of ASD, the specificity of these effects to ASD remains to be determined
SmCL3, a Gastrodermal Cysteine Protease of the Human Blood Fluke Schistosoma mansoni
Parasitic infection caused by blood flukes of the genus Schistosoma is a major global health problem. More than 200 million people are infected. Identifying and characterizing the constituent enzymes of the parasite's biochemical pathways should reveal opportunities for developing new therapies (i.e., vaccines, drugs). Schistosomes feed on host blood, and a number of proteolytic enzymes (proteases) contribute to this process. We have identified and characterized a new protease, SmCL3 (for Schistosoma mansoni cathepsin L3), that is found within the gut tissue of the parasite. We have employed various biochemical and molecular biological methods and sequence similarity analyses to characterize SmCL3 and obtain insights into its possible functions in the parasite, as well as its evolutionary position among cathepsin L proteases in general. SmCL3 hydrolyzes major host blood proteins (serum albumin and hemoglobin) and is expressed in parasite life stages infecting the mammalian host. Enzyme substrate specificity detected by positional scanning-synthetic combinatorial library was confirmed by molecular modeling. A sequence analysis placed SmCL3 to the cluster of other cathepsins L in accordance with previous phylogenetic analyses
Fostering support for non-democratic rule? Controlled political liberalization and popular support for non-democratic regimes
When the Cold War ended, many non-democratic regimes across the globe embarked on a course of controlled political liberalization, hoping to stabilize their autocratic rule by mitigating popular demands for democratization and increasing regime legitimacy. But does this strategy actually work? This article uses multi-level analyses to examine how the degree of political liberalization affects regime support in non-democratic political systems and to ascertain which mechanisms underlie this effect. Drawing on aggregate measures of political liberalization and comparative survey data from four regional survey projects and 31 non-democracies, the study's results indicate that the degree of liberalization has no decisively positive effect on regime support, suggesting controlled political liberalization might not be an effective legitimizing strategy after all.Nach Ende des Kalten Krieges haben viele nicht-demokratische Regime weltweit einen Kurs der begrenzten politischen Ăffnung eingeschlagen, um Ăśffentliche Forderungen nach Demokratisierung zu entschärfen und auf diese Weise die Legitimität ihrer autokratischen Herrschaft zu erhĂśhen. Doch ist diese Strategie tatsächlich effektiv? Der Beitrag verwendet Mehrebenenanalysen, um zu untersuchen wie der Grad an politischer Ăffnung die RegimerunterstĂźtzung in nicht-demokratischen politischen Systemen beeinflusst. Auf Basis von AggregatmaĂen zur politischen Ăffnung und Individualdaten aus vier regionalen Umfrageprojekten und 31 Autokratien kann kein klarer positiver Effekt des Grads der politischen Ăffnung auf die RegimeunterstĂźtzung nachgewiesen werden, was eine begrenzte politische Ăffnung als wenig effektive Legitimationsstrategie erscheinen lässt
Expression of M. tuberculosis-induced suppressor of cytokine signaling (SOCS) 1, SOCS3, FoxP3 and secretion of IL-6 associates with differing clinical severity of tuberculosis
Background
Appropriate immune activation of T cells and macrophages is central for the control of Mycobacterium tuberculosis infections. IFN-Îł stimulated responses are lowered in tuberculosis (TB), while expression of Suppressor of Cytokine Signaling (SOCS) molecules â 1 and 3 and CD4+CD25+FoxP3+T regulatory cells is increased. Here we investigated the association of these molecules in regard to clinical severity of TB. Methods
Peripheral blood mononuclear cells (PBMCs) were isolated from patients with pulmonary TB (PTB, nâ=â33), extra-pulmonary TB (ETB, nâ=â33) and healthy endemic controls (EC, nâ=â15). Cases were classified as moderately advanced or far advanced PTB, and less severe or severe disseminated ETB. M. tuberculosis -stimulated IFN-Îł, SOCS1, SOCS3 and FoxP3 gene expression and secretion of Th1 and Th2 cytokines was measured. Statistical analysis was performed using MannâWhitney U, Wilcoxon Rank and Kruskal Wallis non-parametric tests. Results
In un-stimulated PBMCs, IL-6 (p = 0.018) and IL-10 (p = 0.013) secretion levels were increased in PTB while IL-10 was also increased in ETB (p = 0.003), all in comparison with EC. M. tuberculosis-stimulated IL-6 (p = 0.003) was lowered in ETB as compared with EC. SOCS1 mRNA expression in M. tuberculosis stimulated PBMCs levels in moderately advanced PTB (p = 0.022), far advanced (p = 0.014) PTB, and severe ETB (p = 0.009) were raised as compared with EC. On the other hand, SOCS1 mRNA titers were reduced in less severe ETB, in comparison with severe ETB (p = 0.027) and far advanced PTB (p = 0.016). SOCS3 mRNA accumulation was reduced in far advanced PTB (p = 0.007) and FoxP3 mRNA expression was increased in less severe ETB as compared with EC (p = 0.017). Conclusions
The lowered SOCS1 mRNA levels in patients with less severe extra-pulmonary TB as compared to those with more severe ETB and PTB may lead to elevated IFN-Îł pathway gene expression in the latter group. As localized ETB has shown to be associated with more effective Th1 immunity and adaptive responses, this suggests a role for SOCS1 in determining disease outcome in extra-pulmonary TB
How to increase earthquake and home fire preparedness: the fix-it intervention
Published, evaluated community intervention studies concerning natural hazard preparedness are rare. Most lack a rigorous methodology, thereby hampering the development of evidence-based interventions. This paper describes the rationale and methodology of a cross-cultural, longitudinal intervention study on earthquake and home fire preparedness, termed fix-it. The aim is to evaluate whether and how the intervention brings about behaviour change in the targeted communities in two coastal cities with high seismic risk: Seattle, USA and Izmir, Turkey. Participants are adult residents of these cities. The intervention group attends a 6-h workshop, which focuses on securing items in the household. The control group does not attend the workshop. All participants complete baseline and post-intervention, as well as 3- and 12-month follow-up assessments. The primary outcome measure is an observational measure of nine preparedness items for earthquake and fire in participantsâ homes. This is evaluated alongside participantsâ self-reports concerning their preparedness levels. Secondary outcomes are changes in levels of self-efficacy, perceived outcome, trust, corruption, empowerment, anxiety and social cohesion. Results from the first of the studies, conducted in Seattle in September 2015, indicate that while the fix-it intervention is effective, in the longer term, multi-hazard preparedness is increased by the mere act of going into peopleâs homes to observe their preparedness levels along with assessing self-reported preparedness and sociopsychological orientation towards natural hazards. This protocol and study aim to augment the empirical literature on natural hazard preparedness, informing national and international policy on delivery of evidence-based community interventions to promote multi-hazard preparedness in households
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