Exploring the effects of two-segment loop tunnels on termite food transport efficiency: a simulation study.

This study explores the food transport efficiency (E) in a termite tunnel consisting of a main tunnel and a 2-segment loop tunnel through a model simulation. Simulated termites navigate between the main and loop tunnels through branching nodes (a, b, c, d) with associated probabilities (P1, P2, P3, P4). The loop tunnel locations (δ) are considered: near the nest (δ = 1), at the center of the main tunnel (δ = 2), and close to the food site (δ = 3). The results reveal that for δ = 1, paths such as a → d → b → c and c → d → b → a exhibited high E values. Conversely, for δ = 2, P3 and P4 demonstrate elevated E values ranging from 0.4 to 0.6. For δ = 3, paths like c → d or c → b display high E values, emphasizing the significance of in-loop separation tunnels (characterized by P3 and P4) in alleviating traffic congestion. Partial rank correlation validates that P1 and P2 minimally influence E, while P3 and P4 significantly negatively impact E, regardless of δ. However, for δ = 2, the influence of P3 and P4 is notably reduced due to the positional symmetry of the loop tunnel. In the discussion, we address model limitations and propose strategies to overcome them. Additionally, we outline potential experimental validations to ensure a comprehensive understanding of the dynamics governing termite food transport within tunnels.

Exploring the role of loop tunnels in enhancing termite food transport efficiency: A simulation approach.

Subterranean termites construct a network of tunnels beneath the ground, comprising a main tunnel and branch tunnels. While termites do not construct tunnels that turn back in a "U" shape, the intersection of main and branch tunnels often forms closed curved structures (a loop). The loop structure can have either a positive or negative effect on the transport efficiency of termites in food transportation. However, little research has been conducted on the impact of loop tunnels on transport efficiency (E) due to the technical difficulties associated with direct observation. In this study, we used an individual-based model to simulate termite behavior during food transportation within a tunnel composed of a main tunnel and a loop tunnel. The model incorporates four control variables: the number of introduced simulated termites (k1), the probability of a simulated termite using a loop tunnel when walking towards a food or nest site (k2 or k3), and the length of the loop tunnel (k4). The simulation results reveal that the E value is high for (k2, k3) = (high, high), (low, low), (high, low), and (low, high) when the length of the loop tunnel is relatively short. However, when the length of the loop tunnel is relatively long, E is high only for (k2, k3) = (high, low) and (low, high). We found that these results are primarily influenced by the frequency of traffic jams. Therefore, termites would benefit from adopting strategies that reduce the occurrence of traffic jams during food transportation. In the Discussion section, we briefly touch on the strategy from an ecological perspective.

The effect of avian eggshell membrane structure on microbial penetration: A simulation study.

Avian eggshells exhibit excellent antimicrobial properties. In this study, we conducted simulation experiments to explore the defense mechanisms of eggshell membranes with regards to their physical features. We developed a mathematical model for the movement of microorganisms and estimated their penetration ratio into eggshell membranes based on several factors, including membrane thickness, microbial size, directional drift, and attachment probability to membrane fibers. These results not only suggest that an eggshell membrane with multiple layers and low porosity indicates high antimicrobial performance, but also imply that the fibrous network structure of the membrane might contribute to effective defense. Our simulation results aligned with experimental findings, specifically in measuring the penetration time of Escherichia coli through the eggshell membrane. We briefly discuss the significance and limitations of this pilot study, as well as the potential for these results, to serve as a foundation for the development of antimicrobial materials.

SiSe2 for Superior Sulfide Solid Electrolytes and Li-Ion Batteries.

Among the various existing layered compounds, silicon diselenide (SiSe2) possesses diverse chemical and physical properties, owing to its large interlayer spacing and interesting atomic arrangements. Despite the unique properties of layered SiSe2, it has not yet been used in energy applications. Herein, we introduce the synthesis of layered SiSe2 through a facile solid-state synthetic route and demonstrate its versatility as a sulfide solid electrolyte (SE) additive for all-solid-state batteries (ASSBs) and as an anode material for Li-ion batteries (LIBs). Li-argyrodites with various compositions substituted with SiSe2 are synthesized and evaluated as sulfide SEs for ASSBs. SiSe2-substituted Li-argyrodites exhibit high ionic conductivities, low activation energies, and high air stabilities. In addition, when using a sulfide SE, the ASSB full cell exhibits a high discharge/charge capacity of 202/169 mAh g-1 with a high initial Coulombic efficiency (ICE) of 83.7% and stable capacity retention at 1C after 100 cycles. Furthermore, the Li-storage properties of SiSe2 as an anode material for LIBs are evaluated, and its Li-pathway mechanism is explored by using various cutting-edge ex situ analytical tools. Moreover, the SiSe2 nanocomposite anode exhibits a high Li- insertion/extraction capacity of 950/775 mAh g-1, a high ICE of 81.6%, a fast rate capability, and stable capacity retention after 300 cycles. Accordingly, layered SiSe2 and its versatile applications as a sulfide SE additive for ASSBs and an anode material for LIBs are promising candidates in energy storage applications as well as myriad other applications.

Predicting the presence of an accessory hepatic vein using abdominal computed tomography / Predicción de la presencia de una vena hepática accesoria mediante tomografía computarizada abdominal

The incidence of detection of accessory hepatic vein (AHV) using MRI or CT has been reported. However, previous studies had a small sample size or only reported on the incidence of hepatic vein variants. To the best of our knowledge, there has been no previous report evaluating the factors predictive of the presence of an AHV. To evaluate the incidence and morphology of the accessory hepatic vein (AHV) using multidetector row computed tomography (MDCT) and to investigate the factors which may be helpful in predicting the presence of an AHV. We enrolled 360 patients who underwent abdominal MDCT. We investigated whether the AHV was present and evaluated the frequency of AHVs greater than 5 mm in diameter. We classified the morphology of the AHV entering the inferior vena cava (IVC). We also examined the factors that predicted the presence of an AHV by comparing the diameter of the middle hepatic vein (MHV) and the right hepatic vein (RHV). We identified an AHV in 164 of the 360 patients (45.6 %). Among the 164 AHVs, 56.7 % were larger than 5 mm in diameter. The most common morphologies of the inferior RHV were a single main trunk (58.5 %), followed by two main trunks with a V-shape (19.5 %) and two trunks entering the IVC separately (17.0 %). The possibility that an AHV will be present was significantly higher when the diameter of the RHV was smaller than that of the MHV. MDCT can provide important information regarding AHV incidence and morphology. The possibility of an AHV being present was significantly higher when the diameter of the RHV was smaller than that of the MHV.

Se ha informado de la incidencia de la detección de la vena hepática accesoria (VHA) mediante RM o TC. Sin embargo, estudios previos tenían un tamaño muestral pequeño o solo informaban sobre la incidencia de variantes de las venas hepáticas. Hasta donde sabemos, no ha habido ningún informe previo que evalúe los factores predictivos de la presencia de una VHA. El objetivo del estudio fue evaluar la incidencia y morfología de la vena hepática accesoria (VHA) mediante tomografía computarizada multidetector (TCMD) e investigar los factores que pueden ser útiles para predecir la presencia de un VHA. Se evaluaron 360 pacientes que se sometieron a TCMD abdominal. Se investigó si la VHA estaba presente y se evaluó la frecuencia de VHA mayores de 5 mm de diámetro. Se clasificó la morfología del VHA que drenaba en la vena cava inferior (VCI). Además, se examinaron los factores que predijeron la presencia de una VHA mediante la comparación del diámetro de la vena hepática media (VHM) y la vena hepática derecha (VHD). Se identificó un VHA en 164 de los 360 pacientes (45,6%). Entre las 164 VHA, el 56,7% tenía más de 5 mm de diámetro. Las morfologías más frecuentes del VHD inferior fueron un tronco principal único (58,5%), seguido por dos troncos principales con forma de V (19,5%) y dos troncos que drenaban en la VCI por separado (17,0%). La posibilidad de que una VHA esté presente fue significativamente mayor cuando el diámetro de la VHD era menor que la de la VHM. La MDCT puede proporcionar información importante sobre la incidencia de la VHA y su morfología. La posibilidad de que un VHA estuviera presente era significativamente mayor cuando el diámetro del VHD era menor que la VHM.