Escape dynamics of confined undulating worms

We investigate the escape dynamics of oligochaeta Lumbriculus variegatus by confining them to a quasi-2D circular chamber with a narrow exit passage. The worms move by performing undulatory and peristaltic strokes and use their head to actively probe their surroundings. We show that the worms follow the chamber boundary with occasional reversals in direction and with velocities determined by the orientation angle of the body with respect to the boundary. The average time needed to reach the passage decreases with its width before approaching a constant, consistent with a boundary-following search strategy. We model the search dynamics as a persistent random walk along the boundary and demonstrate that the head increasingly skips over the passage entrance for smaller passage widths due to body undulations. The simulations capture the observed exponential time-distributions taken to reach the exit and their mean as a function of width when starting from random locations. Even after the head penetrates the passage entrance, we find that the worm does not always escape because the head withdraws rhythmically back into the chamber over distances set by the dual stroke amplitudes. Our study highlights the importance of boundary following and body strokes in determining how active matter escapes from enclosed spaces. © 2023 The Royal Society of Chemistry

An Efficient Ranking Technique for Intuitionistic Fuzzy Numbers with Its Application in Chance Constrained Bilevel Programming

The aim of this paper is to develop a new ranking technique for intuitionistic fuzzy numbers using the method of defuzzification based on probability density function of the corresponding membership function, as well as the complement of nonmembership function. Using the proposed ranking technique a methodology for solving linear bilevel fuzzy stochastic programming problem involving normal intuitionistic fuzzy numbers is developed. In the solution process each objective is solved independently to set the individual goal value of the objectives of the decision makers and thereby constructing fuzzy membership goal of the objectives of each decision maker. Finally, a fuzzy goal programming approach is considered to achieve the highest membership degree to the extent possible of each of the membership goals of the decision makers in the decision making context. Illustrative numerical examples are provided to demonstrate the applicability of the proposed methodology and the achieved results are compared with existing techniques

Energetics of twisted elastic filament pairs

We investigate the elastic energy stored in a filament pair as a function of applied twist by measuring torque under prescribed end-to-end separation conditions. We show that the torque increases rapidly to a peak with applied twist when the filaments are initially separate, then decreases to a minimum as the filaments cross and come into contact. The torque then increases again while the filaments form a double helix with increasing twist. A nonlinear elasto-geometric model that combines the effect of geometrical nonlinearities with large stretching and self-twist is shown to capture the evolution of the helical geometry, the torque profile, and the stored energy with twist. We find that a large fraction of the total energy is stored in stretching the filaments, which increases with separation distance and applied tension. We find that only a small fraction of energy is stored in the form of bending energy, and that the contribution due to contact energy is negligible. Our study highlights the consequences of stretchablility on filament twisting which is a fundamental topological transformation relevant to making ropes, tying shoelaces, actuating robots, and the physical properties of entangled polymers

Dynamics of magnetoelastic robots in water-saturated granular beds

We investigate the dynamics of a magnetoelastic robot with a dipolar magnetic head and a slender elastic body as it performs undulatory strokes and burrows through water-saturated granular beds. The robot is actuated by an oscillating magnetic field and moves forward when the stroke amplitude increases above a critical threshold. By visualizing the medium, we show that the undulating body fluidizes the bed, resulting in the appearance of a dynamic burrow, which rapidly closes in behind the moving robot as the medium loses energy. We investigate the applicability of Lighthill\u27s elongated body theory of fish locomotion, and estimate the contribution of thrust generated by the undulating body and the drag incorporating the granular volume fraction-dependent effective viscosity of the medium. The projected speeds are found to be consistent with the measured speeds over a range of frequencies and amplitudes above the onset of forward motion. However, systematic deviations are found to grow with increasing driving, pointing to a need for further sophisticated modeling of the medium-structure interactions. © 2023 American Physical Society

Development of q-Rung Orthopair Trapezoidal Fuzzy Einstein Aggregation Operators and Their Application in MCGDM Problems

Compared to previous extensions, the q-rung orthopair fuzzy sets are superior to intuitionistic ones and Pythagorean ones because they allow decision-makers to use a more extensive domain to present judgment arguments. The purpose of this study is to explore the multicriteria group decision-making (MCGDM) problem with the q-rung orthopair trapezoidal fuzzy (q-ROTrF) context by employing Einstein t-conorms and t-norms. Firstly, some arithmetical operations for q-ROTrF numbers, such as Einstein-based sum, product, scalar multiplication, and exponentiation, are introduced based on Einstein t-conorms and t-norms. Then, Einstein operations-based averaging and geometric aggregation operators (AOs), viz., q-ROTrF Einstein weighted averaging and weighted geometric operators, are developed. Further, some prominent characteristics of the suggested operators are investigated. Then, based on defined AOs, a MCGDM model with q-ROTrF numbers is developed. In accordance with the proposed operators and the developed model, two numerical examples are illustrated. The impacts of the rung parameter on decision results are also analyzed in detail to reflect the suitability and supremacy of the developed approach

Exploration of gaps and challenges in managing burn injury at district and sub-district government health care facilities in Bangladesh

Background: Burn injury is one of the leading cause of mortality and morbidity worldwide. In developing countries like Bangladesh, burn is one of the leading causes of illness, disabilities and deaths. More than 365,000 people are injured every year by electrical, thermal and other causes of burn injuries where 27,000 people needed hospital admission and over 5600 people died. Emergency management of burn at the facility level can reduce the severity of burn injuries and improve overall survival. The study has explored the health care providers’ views on gaps and challenges in management of burn injury at the facilities district and sub district health facilities in Bangladesh. Methodology: A qualitative study was conducted during the period in July 2015. In-depth interviews (n = 19) were performed with the doctors and nurses working in the three district government hospitals and seven sub-district (upazila) government health facilities. Thematic analysis was performed on different themes. Results: Health care providers mentioned that the people are coming to the facilities usually, hours after the incidence. Before visiting the facilities, the burn victims mostly seek treatment from the traditional healers or form village doctors (quack) or from the local pharmacy, over the counter. Family waited until they felt that the patient may not survive. It has identified that delaying in decision making and transferring the patient to the health facility are the key challenges identified by the doctors and nurses when they attended any burn patients in their facility. Moreover, use of different traditional infectious agent in burnt areas from their home make the burn surface more damage. While as, deficiency of adequate supplies, logistics and adequate trainings for the health workers in the facility create much more difficulties to treat a burn patient at primary or secondary health care centers. Conclusion: Burn patients are maltreated in the community before coming to the healthcare facility in most of the cases. The community has misperceptions on burn management which delay the proper management in the facility. Readiness of the facility on the other hand is a big challenge. In order to consistent in burn care in Bangladesh, its equally important to build knowledge and awareness among the community on burn prevention and their role. Like this, readiness of the facilities in time will build confidence in community, thus in turns, will save thousands of lives from burn injury in Bangladesh

DIVERSITY OF GRASSLAND AUCHENORRHYNCHA (CICADIDAE, CERCOPIDAE, CICADELLIDAE AND FULGORIDAE) IN MADHYA PRADESH AND CHHATTISGARH, INDIA

ABSTRACT: Suborder Auchenorrhyncha includes short-horned bugs, having antennae usually small and inconspicuous; when long, they appear slender and filamentous or two segmented. Present study reports 53 species belonging to 37 genera and 8 families of suborder Auchenorrhyncha from Madhya Pradesh and Chhattisgarh. Of these, Infraorder Cicadomorpha represents 44 species, including 10 species belonging to 7 genera of family Cicadidae, 4 species belonging to 4 genera of Superfamily Cercopoidea, 30 species belonging to 20 genera of family Cicadellidae, while Infraorder Fulgoromorpha represents 9 species belonging to 6 genera of Superfamily Fulgoroidea. Present paper also includes 9 new records from Madhya Pradesh and 10 new records from Chhattisgarh

Integrating Apparent Conductance in Resistivity Sounding to Constrain 2D Gravity Modeling for Subsurface Structure Associated with Uranium Mineralization across South Purulia Shear Zone, West Bengal, India

South Purulia Shear Zone (SPSZ) is an important area for the prospect of uranium mineralization and no detailed geophysical investigations have been carried out in this region. To delineate the subsurface structure in the present area, vertical electrical soundings using Schlumberger array and gravity survey were carried out along a profile perpendicular to the SPSZ. Apparent conductance in the subsurface revealed a possible connection from SPSZ to Raghunathpur. The gravity model reveals the presence of a northerly dipping low density zone (most likely the shear zone) extending up to Raghunathpur under a thin cover of granitic schist of Chotanagpur Granite Gneissic Complex (CGGC). The gravity model also depicts the depth of the zone of density low within this shear zone at ~400 m near Raghunathpur village and this zone truncates with a steep slope. Integration of resistivity and gravity study revealed two possible contact zones within this low density zone in the subsurface at depth of 40 m and 200 m. Our study reveals a good correlation with previous studies in Raghunathpur area characterized by medium to high hydro-uranium anomaly. Thus the conducting zone coinciding with the low gravity anomaly is inferred to be a possible uranium mineralized zone