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Abstract

This article deals with balancing an autonomous motorcycle model along a straight line and curve lines. The dynamic model of the motorcycle balancing is described with an inverted physical pendulum loaded with torque. The torque is provided by the inertia of a rotor driven by a direct current motor. The lean angle of the motorcycle is measured by a smart sensor, which is the feedback signal for the linear quadratic regulator control system. The main purpose of this study is to compensate the error of the smart sensor. Controlling the necessary lean angle of the motorcycle during cornering is also addressed.

Open access
Journal of Behavioral Addictions
Authors:
Francky Teddy Endomba
,
Anastasia Demina
,
Vincent Meille
,
Aude Laetitia Ndoadoumgue
,
Celestin Danwang
,
Benjamin Petit
, and
Benoit Trojak

Abstract

Background and aim

In the last two decades, the proportion of internet users has greatly increased worldwide. Data regarding internet addiction (IA) are lacking in Africa compared to other continents. This systematic review and meta-analysis aimed to estimate the pooled prevalence of IA in African countries.

Methods

We systematically sought relevant articles in PubMed/MEDLINE, EMBASE, PsycINFO and Cochrane database published before September 25, 2021. The risk of bias was assessed using the Joanna Briggs Institute tool, and we estimated the pooled prevalence of IA using a random-effects meta-analytic model. We followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines.

Results

We included 22 studies (13,365 participants), and collected data from Egypt, Ethiopia, Morocco, Nigeria, South Africa, Tanzania and Tunisia between 2013 and 2021. The mean age of participants ranged from 14.8 to 26.1 years, and the most used tool for IA screening was the Young's 20-item Internet Addiction Test. The pooled prevalence rate of IA was 40.3% (95% CI: 32.2%–48.7%), with substantial heterogeneity. The pooled prevalence for Northern Africa was 44.6% (95% CI: 32.9%–56.7%), significantly higher than the prevalence in sub-Saharan Africa, which was 31.0% (95% CI: 25.2%–37.1%). The risk of bias was moderate for most studies, the certainty was very low, and we found no publication bias.

Discussion and conclusions

Four in every ten individuals was considered to have IA in Africa. Further research with methodological optimization seems needed, especially for IA screening tools and the representativity of some subregions.

Open access
Imaging
Authors:
Matthew Moore
,
Mohammed Moharram
,
Andre Poon
,
Rexson Tse
,
Hamish M. Aitken-Buck
,
Regis S. Lamberts
, and
Sean Coffey

Abstract

Background and aim

Obesity is associated with an increase in different adipose depots. The anatomic distribution of internal adipose confers different risks. Recently, significant interest has emerged in the expansion of epicardial adipose tissue (EAT) as a mediator of adverse cardiovascular events. Often, post-mortem examination remains the best method of investigating morphological changes in health and disease. This study aimed to develop a simple, reproducible, and non-invasive protocol for the measurement of internal adiposity using post-mortem computed tomography (PMCT).

Patients and methods

101 consecutive post-mortem subjects underwent non-contrast computed tomography scans. Measurements were performed using the open-source software 3D Slicer by a non-expert researcher. An expert radiologist and cardiologist verified the abdominal and cardiac sites of adiposity, respectively. We aimed to develop a protocol to measure total EAT, sub-depots of EAT, extra-pericardial adipose, visceral and subcutaneous adipose, and suprasternal adipose.

Results

We found excellent reproducibility for our measures of total EAT, anterior right atrial EAT, extra-pericardial adipose, and visceral adipose tissue, with intraclass correlations between 0.82 and 0.99 for each measure. Due to a lack of suitable anatomical boundaries, other sub-depots of EAT, including in the interventricular groove, were not reproducible.

Conclusions

Quantification of total EAT and anterior right atrial EAT are readily reproducible using 3D Slicer on post-mortem CT. They can be reliably measured by non-expert researchers with a small amount of training, and therefore be used to investigate morphological changes in adiposity in health and disease.

Open access

Abstract

Empirical research supports the use of psychoactive drugs to augment psychotherapy for the treatment of mental illness. The use of such drugs, however, is still resisted by many in the medical community and this transfers to resistance in the wider community. The stigma of controversy surrounding the drugs, further enhanced by the stigma of mental illness, hinders community acceptance. We report an experiment to change community attitudes to endorse the benefits of such practice. Participants were given information about a client with post-traumatic stress disorder, with accompanying stigma of mental illness, or a physical condition (Parkinson's disease) with comorbid psychological symptoms, but without stigma. They received information about the diagnosis and the value of psychoactive drugs in the enhancement of therapy or this information with a manipulation to induce empathy. Analysis revealed higher empathy for the PTSD than for the Parkinson's patient. The elevation of empathy was further enhanced by the empathy manipulation. While there was higher agreement that PTSD clients were responsible for their own condition, there was a greater willingness to help, and this was further increased by empathy. Such conditions should be considered to encourage the general community to accept enhanced therapy for patients that can enhance endorsement by medical practitioners.

Open access

Abstract

The aim of the study is to determine the environmental conditions in the territory of the Myjava river basin (Slovakia) in order to analyze changes in the ecological stability from the first military mapping (1769–1784) until the present (2020). Except of the assessment of the ecological condition of the area, the stress factors of the territory were evaluated together with proposed measures according to the need to improve the current situation. The ecological prosperity of the landscape was evaluated based on the several methodologies used in Slovakia including coefficients of ecological stability. The results pointed to changes in ecological stability during the period evaluated, together with analyses of the stress factors that are currently affecting the territory researched.

Restricted access

Abstract

Dynamic contact and impact problems are widely applicable. An accurate solution method for these kinds of problems can be used in many fields of mechanical engineering (e.g., cutting metalwork, cogwheel drives, etc.). However, the proper handling of the contact is problematic, as there emerges a substantial amount of nonlinearity in the displacement field. Therefore, a spurious high frequency oscillation is present in the solution. These oscillations must be avoided, as divergence can easily occur in the contact algorithm due to them. In order to eliminate this effect, the applied numerical method must be chosen and set properly. In this study, a comprehensive guide is provided for the appropriate selection of the proper numerical method and its parameters.

Open access

Abstract

In the Hydraulic Laboratory of the Department of Hydraulic Engineering, Faculty of Civil Engineering, Slovak University of Technology in Bratislava the distribution of the flow velocity in a shaft intake structure was investigated on a physical model. The homogeneity of the flow velocity distribution in the intakes of turbines has a great influence on the turbine performance. Modern optical methods, particle image velocimetry and laser Doppler anemometry, were used to measure the flow velocity distribution in the model of the turbine intake. The particle image velocimetry method provides a record of the velocity field, while the laser Doppler anemometry method provides an accurate indication of the velocity at a given point. The flow velocity distributions in the examined profiles were measured by the particle image velocimetry and laser Doppler anemometry methods and the results were compared with each other.

Restricted access

Abstract

Since the eastern enlargement of the European Union (EU), the movement from east to west has become the main driver of intra-EU mobility. Recently, the free movement of labour has been contested not only in the debates around Brexit, but also in other receiving countries. It is not on the political agenda, but several studies have highlighted the economic and demographic effects of massive emigration in eastern EU Member States. More recently, the COVID-19 pandemic has disrupted the functioning of free movement. Economic integration theory assumes that migration continues until wages are equalized in the receiving and sending countries. This paper analyses the perception of intra-EU mobility in the literature and empirically tests whether there is a relationship between the dynamism of income growth in the receiving (Germany, Austria and Spain) and sending (Central and Eastern European) countries, and the dynamism of migration. The empirical results do not support the neoclassical assumption that an equalization mechanism can function, even in the long run. To cope with recent challenges, this paper argues that free movement should not be considered as an element of a spontaneous market mechanism, but as an economic-political product, based on a constitutional order.

Open access

Abstract

On the basis of elaborating the connotation of intensive city block, it is pointed out that the intensive structure organization is the key to realize intensive city block. The order complexity of the block structure is formed by the close connection, overlapping of elements, the depth difference and their compound association. This paper constructs the basic pedigree of block structure design from three levels of street configuration, plot organization and building layout, and forms the derivation and comprehensive application strategy of pedigree from the organic linkage and compound of each other.

Open access

Abstract

Recent literature data indicate that canine and feline neonates are not born in a sterile environment as it was stated previously. The acquisition, colonisation and maintenance of the early life microbiota of healthy fetuses is a rapidly developing research area. In humans, the natural healthy infant microbiome plays an essential role in health and its assembly is determined by the maternal–offspring exchanges of microbes. Even though this topic is becoming more and more important in dogs and cats, the exact role of the neonatal microbiome is not yet fully known in animals. This review summarises the current knowledge of the normal physiological neonatal microbiome in healthy puppies and kittens.

Restricted access