Environment induced emergence of collective behaviour in evolving swarms with limited sensing

Designing controllers for robot swarms is challenging, because human developers have typically no good understanding of the link between the details of a controller that governs individual robots and the swarm behavior that is an indirect result of the interactions between swarm members and the environment. In this paper we investigate whether an evolutionary approach can mitigate this problem. We consider a very challenging task where robots with limited sensing and communication abilities must follow the gradient of an environmental feature and use Differential Evolution to evolve a neural network controller for simulated robots. We conduct a systematic study to measure the flexibility and scalability of the method by varying the size of the arena and number of robots in the swarm. The experiments confirm the feasibility of our approach, the evolved robot controllers induced swarm behavior that solved the task. We found that solutions evolved under the harshest conditions (where the environmental clues were the weakest) were the most flexible and that there is a sweet spot regarding the swarm size. Furthermore, we observed collective motion of the swarm, showcasing truly emergent behavior that was not represented in- and selected for during evolution.Comment: (1) Three authors contributed equally to this researc

Turner syndrome and associated problems in turkish children: A multicenter study

Objective: Turner syndrome (TS) is a chromosomal disorder caused by complete or partial X chromosome monosomy that manifests various clinical features depending on the karyotype and on the genetic background of affected girls. This study aimed to systematically investigate the key clinical features of TS in relationship to karyotype in a large pediatric Turkish patient population. Methods: Our retrospective study included 842 karyotype-proven TS patients aged 0-18 years who were evaluated in 35 different centers in Turkey in the years 2013-2014. Results: The most common karyotype was 45,X (50.7%), followed by 45,X/46,XX (10.8%), 46,X,i(Xq) (10.1%) and 45,X/46,X,i(Xq) (9.5%). Mean age at diagnosis was 10.2±4.4 years. The most common presenting complaints were short stature and delayed puberty. Among patients diagnosed before age one year, the ratio of karyotype 45,X was significantly higher than that of other karyotype groups. Cardiac defects (bicuspid aortic valve, coarctation of the aorta and aortic stenosi) were the most common congenital anomalies, occurring in 25% of the TS cases. This was followed by urinary system anomalies (horseshoe kidney, double collector duct system and renal rotation) detected in 16.3%. Hashimoto’s thyroiditis was found in 11.1% of patients, gastrointestinal abnormalities in 8.9%, ear nose and throat problems in 22.6%, dermatologic problems in 21.8% and osteoporosis in 15.3%. Learning difficulties and/or psychosocial problems were encountered in 39.1%. Insulin resistance and impaired fasting glucose were detected in 3.4% and 2.2%, respectively. Dyslipidemia prevalence was 11.4%. Conclusion: This comprehensive study systematically evaluated the largest group of karyotype-proven TS girls to date. The karyotype distribution, congenital anomaly and comorbidity profile closely parallel that from other countries and support the need for close medical surveillance of these complex patients throughout their lifespan. © Journal of Clinical Research in Pediatric Endocrinology

Differences between autogenous and reactive obsessions in terms of metacognitions and automatic thoughts

İlkay Keleş Altun,1 Emel Uysal,2 Evrim Özkorumak Karagüzel2 1Department of Psychiatry, Kanuni Research and Training Hospital, Trabzon, 2Department of Psychiatry, Karadeniz Technical University, Trabzon, Turkey Background: Obsessive compulsive disorder (OCD) is characterized by obsessions and compulsions. Obsessions have been classified as autogenous obsessions and reactive obsessions on the basis of the cognitive theory of Lee and Kwon. The aim of this study was to investigate the differences between autogenous groups (AG) and reactive groups (RG) in terms of metacognition and automatic thoughts, for the purpose of investigating the differences of cognitive appraisals.Methods: One hundred and thirty-three patients diagnosed with OCD were included in the study as the patient group. A control group was formed of 133 age, gender and education-matched healthy individuals. The OCD group patients were separated into subgroups according to the primary obsessions. The sociodemographic data, and the Yale–Brown Obsessive Compulsive Scale, Metacognition Questionnaire-30 (MCQ-30), Automatic Thoughts Questionnaire (ATQ), Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI) scores of the AG, RG, and control groups were compared.Results: The MCQ-30 (total) and the subscales of MCQ-30 and ATQ scale points were seen to be significantly higher in the AG than in the RG and significantly higher in the RG than in the control group. In the reactive obsession group, the predictive variables of the ATQ points were determined to be MCQ-30 (total), BDI and BAI. In the autogenous obsession group, the predictive variables of the ATQ points were determined to be BDI and BAI.Conclusion: In the current study, differences were determined between the AG and the RG in respect of metacognitions and automatic thoughts. In light of these results, the recommended grouping can be considered useful in the identification of OCD sub-types. There is a need for further studies to identify more homogenous sub-types of OCD. Future multi-centered studies of sub-typing with larger samples using more specific instruments to sub-type and dimensional evaluation will be useful for detailed evaluation and better understanding of the subject. Keywords: obsessive compulsive disorder, autogenous, reactive, obsessions, metacognitions, automatic thought

Modelling thermally induced deformations on tool during turn-mil [Frezeyle tornalamada takimda ortaya çikan termal deformasyonlarin modellenmesi]

It is possible to increase the machined workpiece accuracy and productivity during turn-milling operation by modeling the cutting forces and thermally induced deformations on cutting tool. In order to achieve this task, the main objective of this study is to determine the thermally induced deformations on tool during turn-milling operation and reduce them by applying pressurized cooled air. In this study cutting forces, tool temperatures and deformations modelled by FEM coupled with analytical and mechanistic expressions are compared to those obtained by some series of experiments. It was shown in the study that those deformations could be upto 40% of the depth of cut during fine turn-milling. However they can be reduced by means of cooled air by 65%. Furthermore, tool wear and surface roughness values of machined workpiece were also measured and as it is stated in the paper that the surface values in fine turn-milling operation could be as good as they are in grinding operation

Collective gradient perception with a flying robot swarm

In this paper, we study the problem of collective and emergent sensing with a flying robot swarm in which social interactions among individuals lead to following the gradient of a scalar field in the environment without the need of any gradient sensing capability. We proposed two methods—desired distance modulation and speed modulation—with and without alignment control. In the former, individuals modulate their desired distance to their neighbors and in the latter, they modulate their speed depending on the social interactions with their neighbors and measurements from the environment. Methods are systematically tested using two metrics with different scalar field models, swarm sizes and swarm densities. Experiments are conducted using: (1) a kinematic simulator, (2) a physics-based simulator, and (3) real nano-drone swarm. Results show that using the proposed methods, a swarm—composed of individuals lacking gradient sensing ability—is able to follow the gradient in a scalar field successfully. Results show that when individuals modulate their desired distances, alignment control is not needed but it still increases the performance. However, when individuals modulate their speed, alignment control is needed for collective motion. Real nano-drone experiments reveal that the proposed methods are applicable in real-life scenarios

Environment induced emergence of collective behavior in evolving swarms with limited sensing

Designing controllers for robot swarms is challenging, because human developers have typically no good understanding of the link between the details of a controller that governs individual robots and the swarm behavior that is an indirect result of the interactions between swarm members and the environment. In this paper we investigate whether an evolutionary approach can mitigate this problem. We consider a very challenging task where robots with limited sensing and communication abilities must follow the gradient of an environmental feature and use Differential Evolution to evolve a neural network controller for simulated robots. We conduct a systematic study to measure the flexibility and scalability of the method by varying the size of the arena and number of robots in the swarm. The experiments confirm the feasibility of our approach, the evolved robot controllers induced swarm behavior that solved the task. We found that solutions evolved under the harshest conditions (where the environmental clues were the weakest) were the most flexible and that there is a sweet spot regarding the swarm size. Furthermore, we observed collective motion of the swarm, showcasing truly emergent behavior that was not represented in-and selected for during evolution

Persistent hyperinsulinaemic hypoglycaemia of infancy: case report.

Hyperinsulinism, although rare, is the most common cause of persistent hyperinsulinaemic hypoglycaemia in infancy. Because of persistent hypoglycaemia, serious difficulties are encountered in the long term management of this condition. A male neonate, after an uncomplicated full-term pregnancy, had been admitted to another hospital with convulsions on the third post-natal day. Meningitis had been suspected at that time and treated with phenobarbital and he had been discharged from the hospital. At three-months old he was referred to our department for persistent convulsions and lethargy. His parents were of 1st degree consanguinity. His blood glucose level was found to be 24 mg/dl (1.33 mmol/L). Because of the dangerously high insulin level during hypoglycaemia (insulin/glucose > 0.3), the absence of ketonuria, and the need for a high dose of glucose infusion (> 15 mg/kg/min) to achieve normoglycaemia and a glycaemic response to glucagon despite the hypoglycaemia, a diagnosis of persistent hyperinsulinaemic hypoglycaemia of infancy was made. Since maximal doses of prednisone, glucagon, diazoxide, octreotide and high infusion of glucose were ineffective in achieving normoglycaemia, a subtotal (80%) pancreatectomy was done. Postoperatively intermittent hypoglycaemic episodes continued. These were controlled with low doses of octreotide. Histology revealed diffuse adenomatous hyperplasia (nesidoblastosis). The boy is now in the sixth post-operative month and developing normally

PERSISTENT HYPERINSULINAEMIC HYPOGLYCAEMIA OF INFANCY: CASE REPORT

Hyperinsulinism, although rare, is the most common cause of persistent hyperinsulinaemichypoglycaemia in infancy. Because of persistent hypoglycaemia, serious difficulties areencountered in the long term management of this condition. A male neonate, after anuncomplicated full-term pregnancy, had been admitted to another hospital withconvulsions on the third post-natal day. Meningitis had been suspected at that timeand treated with phenobarbital and he had been discharged from the hospital. At threemonthsold he was referred to our department for persistent convulsions and lethargy.His parents were of 1st degree consanguinity. His blood glucose level was found to be24 mg/dl (1.33 mmol/L). Because of the dangerously high insulin level during hypoglycaemia(insulin/glucose >0.3), the absence of ketonuria, and the need for a high dose of glucoseinfusion (> 15 mg/kg/min) to achieve normoglycaemia and a glycaemic response toglucagon despite the hypoglycaemia, a diagnosis of persistent hyperinsulinaemichypoglycaemia of infancy was made. Since maximal doses of prednisone, glucagon,diazoxide, octreotide and high infusion of glucose were ineffective in achievingnormoglycaemia, a subtotal (80%) pancreatectomy was done. Postoperatively intermittenthypoglycaemic episodes continued. These were controlled with low doses of octreotide.Histology revealed diffuse adenomatous hyperplasia (nesidoblastosis). The boy is nowin the sixth post-operative month and developing normally