Self-organized flocking in mobile robot swarms

In this paper, we study self-organized flocking in a swarm of mobile robots. We present Kobot, a mobile robot platform developed specifically for swarm robotic studies. We describe its infrared-based short range sensing system, capable of measuring the distance from obstacles and detecting kin robots, and a novel sensing system called the virtual heading system (VHS) which uses a digital compass and a wireless communication module for sensing the relative headings of neighboring robots. We propose a behavior based on heading alignment and proximal control that is capable of generating self-organized flocking in a swarm of Kobots. By self-organized flocking we mean that a swarm of mobile robots, initially connected via proximal sensing, is able to wander in an environment by moving as a coherent group in open space and to avoid obstacles as if it were a “super-organism”. We propose a number of metrics to evaluate the quality of flocking. We use a default set of behavioral parameter values that can generate acceptable flocking in robots, and analyze the sensitivity of the flocking behavior against changes in each of the parameters using the metrics that were proposed. We show that the proposed behavior can generate flocking in a small group of physical robots in a closed arena as well as in a swarm of 1000 simulated robots in open space. We vary the three main characteristics of the VHS, namely: (1) the amount and nature of noise in the measurement of heading, (2) the number of VHS neighbors, and (3) the range of wireless communication. Our experiments show that the range of communication is the main factor that determines the maximum number of robots that can flock together and that the behavior is highly robust against the other two VHS characteristics. We conclude by discussing this result in the light of related theoretical studies in statistical physics.     

Design,synthesis and docking study of novel coumarin ligands as potential selective acetylcholinesterase inhibitors

New coumaryl-thiazole derivatives with the acetamide moiety as a linker between the alkyl chains and/or the heterocycle nucleus were synthesized and in vitro tested as acetylcholinesterase (AChE) inhibitors. 2-(diethylamino)-N-(4-(2-oxo-2H-chromen-3-yl)thiazol-2-yl)acetamide (6c, IC₅₀ value of 43?nM) was the best AChE inhibitor with a selectivity index of 4151.16 over BuChE. Kinetic study of AChE inhibition revealed that 6c was a mixed-type inhibitor. Moreover, the result of H4IIE hepatoma cell toxicity assay for 6c showed negligible cell death. Molecular docking studies were also carried out to clarify the inhibition mode of the more active compounds. Best pose of compound 6c is positioned into the active site with the coumarin ring wedged between the residues of the CAS and catalytic triad of AChE. In addition, the coumarin ring is anchored into the gorge of the enzyme by H-bond with Tyr130.     

Biosorption of Food Green 3 by a novel green generation composite biosorbent from aqueous environment

A green type composite biosorbent composed of pine, oak, hornbeam, and fir sawdust biomasses modified with cetyltrimethylammonium bromide (CTAB) was first used for biosorption of an unsafe synthetic food dye, Food Green 3 from liquid medium in this study. Batch studies were carried by observing the effects of pH, dye concentration, biosorbent amount, and contact time. The equilibrium data were analyzed using Freundlich, Langmuir, and Dubinin–Radushkevich equations. Freundlich model gave a better conformity than other equations. The maximum dye removal potential of biosorbent was found to be 36.6 mg/g based on Langmuir isotherm. The pseudo-first-order, pseudo-second-order, Elovich, and intra-particle diffusion models were applied to clarify the process kinetics of biosorption. The mechanism studies suggested the biosorption process obeying Elovich kinetics and involving pore diffusion. The estimated values of biosorption free energy from Dubinin–Radushkevich isotherm (E value <8 kJ/mol) and thermodynamic studies (0 < ΔG° < ?20 kJ/mol) implied a spontaneous, feasible, and physical process. Hence, this investigation suggested that the CTAB modified mix sawdust biomass could be a promising biosorbent for biosorption of such problematic dyes from impacted media.     

Difficulties in the diagnosis of HbS/beta thalassemia: Really a mild disease?

BackgroundHbS/b cases having clinical, hematologic and electrophoretic similarities cannot be sufficiently distinguished from sickle cell anemia cases and are misdiagnosed as sickle cell anemia. This study will investigate the congruence between the HPLC thalassemia scanning tests and the laboratory findings compared to the DNA sequence analysis results of the patients diagnosed with SCA between 2016 and 2020. This study also aims to indicate the current status to accurately diagnose sickle cell anemia and HbS/b in the light of hematologic, electrophoretic and molecular studies.MethodsFourteen patients who were diagnosed with SCA in hospitals at different cities in Turkey and followed by the Thalassemia Diagnosis, Treatment and Research Center, Muğla Sıtkı Koçman University were included in this retrospective study. The socio-demographic characteristics, hemogram, hemoglobin variant analysis results and DNA chain analysis results of the patients were taken from the database of the centre and then examined. The informed consents were taken from the patients. The patients were administered a survey containing questions about transfusion history and diagnostic awareness. The Beta-Thalassemia mutations were analysed using a DNA sequencer (Dade Behring, Germany) based on the Sanger method.ResultsAccording to the DNA sequence analysis, the results of these patients diagnosed with SCA in hospitals in different cities of Turkey were the following: of 14 patients, 8 had HbS/b0, and HbS/b+ and one had HbS carrier, and one had Hb-O, and three had SCA. The patient with HbS carrier status also contains three additional mutations, all of which are heterozygous. We discovered that although two of three mutations, which are c.315+16G>C and c.316-185C>T, are previously reported as benign, at least one of the two mentioned mutations, when combined with HbS, causes transfusion-dependent HbS/b.ConclusionsBriefly, HbSS and HbS/b thalassemia genotypes cannot be definitely characterized by electrophoretic and hematologic data, resulting in misdiagnosis. c.315+16G>C and c.316-185C>T are previously reported as benign; at least one of the two mentioned mutations, when combined with HbS, causes transfusion-dependent HbS/b. In undeveloped or some developing countries, molecular diagnosis methods and genetic analyses cannot be used. If mutation analyses could be performed, then such differential diagnosis errors would reduce. However, if mutation analysis cannot be performed, other methods such as HPLC, capillary electrophoresis absolutely be sought to have insight into the parental carriage status.     

MAPKAP kinase MK2 maintains self‐renewal capacity of haematopoietic stem cells

The structurally related MAPK‐activated protein kinases (MAPKAPKs or MKs) MK2, MK3 and MK5 are involved in multiple cellular functions, including cell‐cycle control and cellular differentiation. Here, we show that after deregulation of cell‐cycle progression, haematopoietic stem cells (HSCs) in MK2‐deficient mice are reduced in number and show an impaired ability for competitive repopulation in vivo. To understand the underlying molecular mechanism, we dissected the role of MK2 in association with the polycomb group complex (PcG) and generated a MK2 mutant, which is no longer able to bind to PcG. The reduced ability for repopulation is rescued by re‐introduction of MK2, but not by the Edr2‐non‐binding mutant of MK2. Thus, MK2 emerges as a regulator of HSC homeostasis, which could act through chromatin remodelling by the PcG complex.     

Elemi essential oil nanocapsulated drug ameliorates lung cancer via oxidative stress,apoptosis and inflammation pathway

Lung cancer is one of the most common causes of death in the world. Considering the severe side effects, toxicity and high costs of chemotherapeutics used in cancer treatment, there is a need for more economical and natural treatment methods such as essential oils. The purpose of this study is to determine the efficacy of Canarium commune (Elemi) essential oil (EO) and nanoparticles. Elemi EO is analysed by GC-FID/MS. The antiproliferative effect of Elemi EO and prepared nanoparticles on human lung adenocarcinoma (A549) and their effect on normal fibroblast cells (CCD-19Lu) were determined by the MTT test. The levels of TAS, TOS, CYCS, CASP3, TNF-α and IL-6 parameters of the experimental groups were determined using specific ELISA. BAX and Bcl-2 genes were studied with qRT-PCR to investigate the different ways that cancer cells undergo apoptosis. Limonene (53.7%), a-phellandrene (14.5%) and elemol (10.1%) were the major components of Elemi EO. 24-Hour IC₅₀ values in the cells were measured for Elemi EO; A549: 1199 μg/mL, CCD-19Lu: 37.181 μg/mL. TAS and TOS values were found to be higher in cancer cells than in normal cells, and it was found that cancerous cells were dragged into stress and that cancer cells were directed to apoptosis. BAX genes stimulation supported the results. It was determined that Elemi EO and nanoparticles showed anticancer activity without damaging normal cells. Based on these promising results, potential drug candidate Elemi EO loaded nanoparticles may be cell-specific targeted, oral use possible, new generation nanoparticular drugs.     

Analysis of Quinolinequinone Analogs with Promising Cytotoxic Activity against Breast Cancer

It is quite challenging to find out bioactive molecules in the vast chemical universe. Quinone moiety is a unique structure with a variety of biological properties, particularly in the treatment of cancer. In an effort to develop potent and secure antiproliferative lead compounds, five quinolinequinones ( AQQ1-5 ) described previously have been selected and submitted to the National Cancer Institute (NCI) of Bethesda to envisage their antiproliferative profile based on the NCI Developmental Therapeutics Program. According to the preliminary in vitro single-dose anticancer screening, four of five quinolinequinones ( AQQ2-5 ) were selected for five-dose screening and they displayed promising antiproliferative effects against several cancer types. All AQQs showed a excellent anticancer profile with low micromolar GI₅₀ and TGI values against all leukemia cell lines, some non-small cell lung and ovarian cancer, most colon, melanoma, and renal cancer, and in addition to some breast cancer cell lines. AQQ2-5 reduced the proliferation of all leukemia cell lines at a single dose and five additional doses, as well as some non-small cell lung and ovarian cancer, the majority of colon cancer, melanoma and renal cancer, and some breast cancer cell lines. This motivated us to use in vitro, in silico, and in vivo technologies to further investigate their mode of action. We investigated the in vitro cytotoxic activities of the most promising compounds, AQQ2 and AQQ3 , in HCT-116 colon cancer, MCF7 and T-47D breast cancer, and DU-145 prostate cancer cell lines, and HaCaT human keratinocytes. Concomitantly, IC₅₀ values of AQQ2 and AAQ3 against MCF7 and T-47D cell lines of breast cancer, DU-145 cell lines of prostate cancer, HCT-116 cell lines of colon cancer, and HaCaT human keratinocytes were determined. AQQ2 exhibited anticancer activity through the induction of apoptosis and caused alterations in the cell cycle. In silico pharmacokinetic studies of all analogs have been carried out against ATR, CHK1, WEE1, CDK1, and CDK2. In addition to this, in vitro ADME and in vivo pharmacokinetic profiling for the most effective AAQ ( AAQ2 ) have been studied.     

Oxidative stress status in familial Mediterranean fever with or without proteinuria

Although several studies have indicated oxidative system abnormalities in patients with familial Mediterranean fever, it is still obscure whether proteinuria seen in this disease has an effect on the oxidative system. In the present study, oxidative system changes were investigated in familial Mediterranean fever with or without proteinuria. Plasma malondialdehyde levels in proteinuric and nonproteinuric patients were higher than those of the controls and they were also significantly higher in the patients with proteinuria compared to patients without proteinuria. The patients had significantly lower plasma glutathione peroxidase activities than the controls. Glutathione peroxidase activities did not show statistically significant differences between the patients with and those without proteinuria. A significant difference was not established for erythrocyte superoxide dismutase activities. These data suggest that there is an increase in lipid peroxidation in familial Mediterranean fever. Decreased plasma glutathione peroxidase activities seem to be responsible for increased plasma malondialdehyde levels in both patient groups. However, the fact that higher plasma malondialdehyde levels in proteinuric patients were observed compared to nonproteinuric patients in the presence of the unchanged plasma glutathione peroxidase activities in these groups suggests that the nephrotic state may have a contribution to this situation.     

Height, weight, IGF-I, IGFBP-3 and thyroid functions in prepubertal children with attention deficit hyperactivity disorder: effect of methylphenidate treatment

OBJECTIVE: To investigate if there are any disease-related or methylphenidate-induced aberrations in growth parameters, growth hormone insulin-like growth factor (IGF)-I, IGFBP-3 axis and the thyroid function tests in children with attention deficit hyperactivity disorder (ADHD). METHODS: Newly diagnosed and untreated prepubertal children with ADHD were longitudinally followed before and approximately every 4 months after methylphenidate treatment for up to 16 months. Height SDS, weight SDS, BMI SDS, serum GH, IGF-I, IGFBP-3, T4, free T4, T3, and TSH were measured at each visit. RESULTS: All of the examined parameters were within normal limits for age before treatment. Methylphenidate treatment did not significantly affect SDS of height, weight, BMI, IGF-I and IGFBP-3 in the long run. Serum T4 and free T4 levels showed modest reductions within normal limits in a time-dependent manner. CONCLUSIONS: Prepubertal children with ADHD had normal height, weight, BMI, serum IGF-I and IGFBP-3 and thyroid functions. Methylphenidate treatment had no sustained effects on growth parameters, IGF-I and IGFBP-3 during the follow-up period of this study. However, it caused a mild decrease in total and free T4 which may warrant further monitoring.     

Application of a novel phyco-composite biosorbent for the biotreatment of aqueous medium polluted with manganese ions

A composite phyco-biomass including four different marine macroalgae species (Chaetomorpha sp., Polysiphonia sp., Ulva sp., and Cystoseira sp.) was evaluated as a novel biosorbent for the biosorption of manganese ions from aqueous solution. The experimental studies were performed to optimize the operational factors including solution pH, biosorbent amount, initial manganese concentration, and reaction time in a batch-mode biosorption system. The removal yield of the biosorbent for manganese ions increased with increasing pH, manganese ion concentration, and reaction time, while it decreased as the biosorbent dose increased. The obtained kinetic data indicated that the removal of manganese ions by the biosorbent was best described by the pseudo-second-order model and the pore diffusion also contributed to the biosorption process. The results of isotherm and thermodynamic studies showed that the Freundlich model represented the biosorption equilibrium data well and this biotreatment system was feasible, spontaneous, and physical. The maximum manganese uptake capacity of used biosorbent was found to be 55.874 mg g^?1. Finally, a single-stage batch manganese biosorption system was designed and its kinetic performance was evaluated. All these findings revealed that the prepared composite macroalgae biosorbent has a fairly good potential for the removal of manganese ions from the aqueous medium.