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This paper explores two non‐linear control techniques for designing an effective control system for an omnidirectional autonomous mobile robot with four Mecanum wheels. Due to the unique wheel structure and four separate wheels, the robot has non‐linear dynamics, multiple inputs and outputs. The first technique uses the state‐dependent Riccati equation (SDRE) to address optimal non‐linear control while considering energy and time constraints. The second technique, using an intermediate variable θ $\\theta $ , has expanded the Hamilton‐Jacobi‐Belman equation in terms of the power series. Consequently, these equations are reduced to a set of recursive Lyapunov algebraic equations, leading to a closed‐form solution for solving the non‐linear optimal control problem. Finally, the maneuverability and path‐tracking capability of the robot are examined by highlighting the non‐linear term through numerical simulation. This paper explores two non‐linear control techniques for designing an effective control system for an omnidirectional autonomous mobile robot with four Mecanum wheels. Due to the unique wheel structure and four separate wheels, the robot has non‐linear dynamics and multiple inputs and outputs.

Sinkholes and land cracks are the phenomena that are common in the semi-arid and arid lands. The destructive effects of sinkholes include destruction of infrastructure such as energy transmission lines and buildings including residential areas which lead to dangers to human life. In the study area, water abstraction from groundwater for irrigation intensified the sinkhole and land crack formation. Soil parameters such as clay percentage, cracks, and sinkholes dominated in different lands. This study focused on the Abarkooh plain with an area of about 200 square kilometers. The region consisted of medium to fine particles of an alluvial fan that had led from the southwest to the northeast which terminated to low land of Abarkooh salty playa. In this research, 129 samples were taken at grid points from the top soils, and four soil samples were collected from the profile of the sample sinkhole for detailed chemical, physical, and mechanical analyses. Clay mineralogy was performed from selected soil samples after primary routine chemical, physical, and mechanical analyses. Multiple linear regression (MLR) as mathematical function was used for predicting sinkhole hazards with soil properties data. The results revealed that soil properties such as water-soluble Na + and Mg 2+ and lime percentage in the soils had important role to soil divergence and liquid soil clays for sinkhole occurrence. Clay mineralogy from clay particles demonstrated that the mixed clay minerals with dominance of chlorite in the area and play the role of montmorillonite could cause soil divergence. The MLR could predict sinkhole hazard with high accuracy, and the ground-penetrating radar (GPR) results confirmed it as complementary method test. It is suggested that land conservation be introduced as the best alternative in the hazard zones of the sinkhole.

The emergence of antibiotic-resistant bacteria, dubbed superbugs, together with relative stagnation in developing efficient antibiotics has led to enormous health and economic problems, necessitating the need for discovering and developing novel antimicrobial agents. In this respect, animal venoms represent a rich repertoire of pharmacologically active components. As a major component in the venom of European honeybee Apis mellifera , melittin has a great potential in medical applications. In this mini-review, we summarize a multitude of studies on anti-bacterial effects of melittin against planktonic and biofilm-embedded bacteria. Several investigations regarding synergistic effects between melittin and antibiotics were also described. On the whole, the properties of melittin can open up new horizons in a range of biomedical areas, from agriculture to veterinary and clinical microbiology.

Nowadays, direct absorption solar collectors are a new concept of solar collectors which have attracted special attention. The type of heat transfer fluid (HTF) has a significant influence on the efficiency of this kind of collector. Therefore, in this study, a wide range of working fluids including mono nanofluid (Al 2 O 3${\\text{Al}}_{2}{{\\rm{O}}}_{3}$and CuO), binary nanofluid, and especially the incorporation of a new hybrid combination of nanofluid and microencapsulated phase change material (MPCM), are used as the working fluids of a triple‐walled direct absorption evacuated tube solar collector. The computational fluid dynamics (CFD) method is used for simulating the collector and investigating the effect of different parameters including volume fraction, base fluid, mass flow rate, and type of absorber tube structure (double‐ and triple‐walled) on collector thermal performance. Results show that binary nanofluids of 0.06% Al 2 O 3${\\text{Al}}_{2}{{\\rm{O}}}_{3}$ /0.002% CuO/water and 0.06% Al 2 O 3${\\text{Al}}_{2}{{\\rm{O}}}_{3}$ /0.002% CuO/ethylene glycol (EG) have the largest working fluid temperature differentials equal to 48.31 and 66.5 K, respectively. It was inferred that, at the mass flow rate of 2.7 kg / h$\\mathrm{kg}/{\\rm{h}}$ , the efficiency is obtained to be 60.29% employing binary/EG nanofluid, which is 8.68% and 15.31% higher than CuO/EG and Al 2 O 3${\\text{Al}}_{2}{{\\rm{O}}}_{3}$ /EG nanofluids, respectively. Inserting the hybrid CuO nanofluid/MPCM leads to an improvement of 1.14% and 1.22% in the efficiency of triple‐ and double‐walled collectors, respectively, with respect to the individual usage of the nanofluid. The thermal efficiency of the double‐walled structure is higher than triple‐walled considering all HTFs. Nanofluid/microencapsulated phase change material (MPCM)‐based triple‐wall direct absorption evacuated tube collector.

Background Zimmermann-Laband Syndrome (ZLS) and infantile systemic hyalinosis (ISH) are rare genetic disorders. They are characterized by various spectrum manifestations. In spite of other case reports, this case with features of both syndromes was reported by oral medicine specialists and oral and maxillofacial surgeons. Case presentation In this study, we reported an 18-months old female patient with gingival overgrowth. This phenomenon completely embedded all the erupted teeth. In this case, the presence of multiple papulonodular cutaneous lesions is a newly observed aspect that has rarely been reported in the existing literature. Gingival overgrowth was excised under general anesthesia. At six months of follow-up after surgery, mastication and breathing problems were improved. Aesthetic aspects were ameliorated in terms of gingival appearance. Conclusions To date, due to the ambiguous presentations, both syndromes remain an enigma for specialists. A timely diagnosis could be crucial for prognosis and preventing severe further surcharge. Dentists could play an important role in the diagnosis of rare disorders.

Bioactive peptide-based drugs have gained exceeding attention as promising treatments for infectious and oxidative-stress-related diseases, are exacerbated by the advent and spread of various multidrug-resistant bacteria and industrial lifestyles. Fish skin mucus has been recognized as a potential source of bioactive peptides, providing the first line of fish defense against invading pathogens which are targeted here to be explored as a new source of biopharmaceutics. Peptide fractions were isolated from the epidermal exudates of Caspian sand goby, Neogobius fluviatilis pallasi, by solid-phase extraction (SPE), ultrafiltration, and reversed-phase chromatography. The resulting fractions were characterized for their antibacterial and antioxidant properties, and results showed that the molecular weight fraction < 5 kDa represented the highest ( p  < 0.05) bacterial inhibition activity against Staphylococcus aureus and Bacillus subtilis as well as scavenging activity against DPPH and ABTS radicals. Overall, these results introduce the epidermal mucus of Caspian sand goby as a valuable source of bioactive compounds that can be considered new and efficient biopharmaceutics.

High-fat diets (HFDs) are widely used in aquaculture but may adversely affect fish liver health by disturbing lipid metabolism and promoting oxidative stress. This study investigated the protective effects of Nannochloropsis oculata enriched with astaxanthin on zebrafish ( Danio rerio ) fed an HFD. All zebrafish ( n  = 135) were divided randomly into three groups: conventional diet (CD), high-fat diet (HFD), and HFD supplemented with 2% N. oculata (HFD + NO). After a four-week feeding trial, growth performance, hepatosomatic index, liver oxidative stress markers, and expression of immune cytokine genes were evaluated. HFD group exhibited significantly increased hepatic lipid accumulation, elevated serum triglycerides and total cholesterol, and increased liver marker enzymes. These changes were accompanied by reduced antioxidant enzyme and non-enzymatic antioxidant activity, heightened oxidative stress, and upregulated pro-inflammatory cytokine expression ( il-1β and il-8 ). Histological analysis confirmed hepatic steatosis and structural deterioration. Conversely, N. oculata supplementation significantly alleviated these effects by reducing hepatic lipid deposition, restoring antioxidant defenses, and downregulating pro-inflammatory cytokines while upregulating anti-inflammatory responses ( IL-10 and TGF-β ). These protective effects are attributed to astaxanthin’s role in boosting mitochondrial β-oxidation, suppressing lipogenesis, and modulating inflammatory pathways. These findings suggest that N. oculata is a promising functional feed additive for mitigating diet-induced liver dysfunctions in aquaculture. Further research is needed to elucidate its molecular mechanisms and assess its long-term benefits across diverse aquatic environments.

Molar--incisor hypomineralization (MIH) could be appeared in condition of calcium (Ca ) disorders. Body height is an index of growth health monitoring in child that may be assumed by calcium metabolism. This study was designed to compare the body height of 8--9 years old schoolchildren with MIH and control group. This cross-sectional study was carried out by examination of 606 Iranian healthy schoolchildren for recording enamel defects and body height measurements by a single trained examiner. Putative etiological factors were evaluated using the structured questionnaire. The questionnaire was about maternal, prenatal, and postnatal factors. Statically analysis was done using -test and Chi-square test in SPSS 22. The prevalence of MIH in the schoolchildren was 52.9%. Prevalence of MIH significantly was higher in girls. Most of maternal and child's parameters appeared to have no significant correlation with MIH except birth weight, antibiotic therapy, maternal disease in pregnancy, and medication ( < 0.05). In spite of lower body height in schoolchildren with MIH, there was not any significant correlation between them.

A series of large scale oedometer experiments were carried out to investigate the settlement of sand reinforced with tire derived aggregates (TDA). The parameters studied were five different amounts of TDAs, three aspect ratios and relative skeletal densities, and seven overburden pressures. The volume compressibility coefficient was calculated against different input parameters, and the constraint condition used enabled Poisson’s ratio to be calculated from an “at-rest” coefficient of earth pressure. The triaxial modulus was calculated indirectly and then adopted in subsequent numerical analyses. Finite element analysis and Monte Carlo simulations were used to investigate the settlement of this mixture and to study how the different parameters affected the settlement mixtures of sand and TDAs. The experimental and numerical results reveal that the amount of TDAs is the major parameter which affects settlement, although the overburden pressure and relative skeletal density are also important. The aspect ratio of the shred has almost no effect on volume compressibility parameters as long as constraint compression condition governs. Two index parameters were defined to discuss the type of shred distribution and how it affects settlement of the mixture.

Cathelicidins are a family of antimicrobial peptides which exhibit broad antimicrobial activities against antibiotic-resistant bacteria. Considering the progressive antibiotic resistance, cathelicidin is a candidate for use as an alternative approach to treat and overcome the challenge of antimicrobial resistance. Cathelicidin-BF (Cath-BF) is a short antimicrobial peptide, which was originally extracted from the venom of Bungarus fasciatus . Recent studies have reported that Cath-BF and some related derivatives exert strong antimicrobial and weak hemolytic properties. This study investigates the bactericidal and cytotoxic effects of Cath-BF and its analogs (Cath-A and Cath-B). Cath-A and Cath-B were designed to increase their net positive charge, to have more activity against methicillin resistant S. aureus (MRSA). The results of this study show that Cath-A, with a +17-net charge, has the most noteworthy antimicrobial activity against MRSA strains, with minimum inhibitory concentration (MIC) ranging between 32–128 μg/ml. The bacterial kinetic analysis by 1 × MIC concentration of each peptide shows that Cath-A neutralizes the clinical MRSA isolate for 60 min. The present data support the notion that increasing the positive net charge of antimicrobial peptides can increase their potential antimicrobial activity. Cath-A also displayed the weakest cytotoxicity effect against human umbilical vein endothelial and H9c2 rat cardiomyoblast cell lines. Analysis of the hemolytic activity reveals that all three peptides exhibit minor hemolytic activity against human erythrocytes at concentrations up to 250 μg/ml. Altogether, these results suggest that Cath-A and Cath-B are competent candidates as novel antimicrobial compounds against MRSA and possibly other multidrug resistant bacteria.