Behavior of Ants Escaping from a Single-Exit Room

<div><p>To study the rules of ant behavior and group-formation phenomena, we examined the behaviors of <i>Camponotus japonicus</i>, a species of large ant, in a range of situations. For these experiments, ants were placed inside a rectangular chamber with a single exit that also contained a filter paper soaked in citronella oil, a powerful repellent. The ants formed several groups as they moved toward the exit to escape. We measured the time intervals between individual escapes in six versions of the experiment, each containing an exit of a different width, to quantify the movement of the groups. As the ants exited the chamber, the time intervals between individual escapes changed and the frequency distribution of the time intervals exhibited exponential decay. We also investigated the relationship between the number of ants in a group and the group flow rate.</p></div

Relationship between the number of ants in a group (<i>S</i>) and <i>Q</i>_<i>S</i> through an exit.

<p>(A), (B) and (C) show the relationship between <i>S</i> and <i>Q</i>_{<b><i>S</i></b>} for the 1<i>w</i> (when <i>N</i>≥2), 2<i>w</i>-6<i>w</i> (when <i>N</i>≥2) and 2<i>w</i>-6<i>w</i> (when <i>N</i>≥3) exit widths, respectively. (A), (B) and (C) reveal a trend toward an increase in <i>Q</i>_{<b><i>S</i></b>} with increasing <i>S</i> only when the exit width was 1<i>w</i> (0.5 cm).</p

<i>Q</i> (mean flow rate) of all of experimental repetitions for the six different exit widths.

<p>The six exit widths were 1<i>w</i> (0.5 cm), 2<i>w</i> (1.0 cm), 3<i>w</i> (1.5 cm), 4<i>w</i> (2.0 cm), 5<i>w</i> (2.5 cm), and 6<i>w</i> (3.0 cm). The square represents the <i>Q</i> (mean flow rate) for each exit width. The data indicate no obvious linear relationship between <i>Q</i> (mean flow rate) and <i>d</i> (exit size).</p

Time interval frequency distribution of all repetitions of the experiments for each exit width.

<p>The histogram represents the experimental results for each exit width, and the solid line represents the result of nonlinear fitting. (A), (B), (C), (D), (E), and (F) depict the frequency distributions of the time intervals in the six experimental repetitions for exit sizes of 1<i>w</i> = 0.5 cm, 2<i>w</i> = 1.0 cm, 3<i>w</i> = 1.5 cm, 4<i>w</i> = 2.0 cm, 5<i>w</i> = 2.5 cm, and 6<i>w</i> = 3.0 cm. All of the results show exponential decay based on nonlinear fitting.</p

Escape distribution of ants under the effect of a repellent.

<p>(A), (B) The temporal evolution of the number of ants escaping through an exit size of 1<i>w</i> = 0.5 cm and other exit sizes (2<i>w</i> = 1.0 cm, 3<i>w</i> = 1.5 cm, 4<i>w</i> = 2.0 cm, 5<i>w</i> = 2.5 cm, and 6<i>w</i> = 3.0 cm); the data of one experimental repetition is shown. The solid line represents the result of nonlinear fitting. The flow of ants is divided into several groups. Solid line: </p><p></p><p></p><p><mi>y</mi><mo>=</mo><mo stretchy="false">(</mo><mi>A</mi><mn>1</mn><mo stretchy="false">)</mo><mo>*</mo>exp<mo stretchy="false">(</mo></p><p></p><p><mo>−</mo><mi>x</mi></p><p><mi>t</mi><mn>1</mn></p><p></p><mo stretchy="false">)</mo><mo>+</mo><mi>y</mi><mn>0</mn><p></p><p></p><p></p>; where y represents the number of escaped ants, and x represents time.<p></p

Table_1_Analysis of Efficacy and Safety of Modified Transfrontal Puncture Drainage in Hypertensive Basal Ganglia Hemorrhage Patients.DOCX

ObjectiveThe study aimed to explore the efficacy and safety of modified transfrontal puncture drainage in patients with hypertensive basal ganglia hemorrhage.MethodsThe study enrolled 102 patients with hypertensive basal ganglia hemorrhage who received treatment at our hospital between April 2020 and June 2020. They were divided into a control group (51 cases, burr hole evacuation of intracranial hematoma) and a study group (51 cases, modified transfrontal puncture drainage) using the random number table method. The operative time, hematoma evacuation rate, time to recovery of consciousness, postoperative Glasgow coma scales (GOS), and the length of hospital stay were compared between the two groups. The postoperative recovery of neurological function in the two groups was observed, and activities of daily living at 3 months postoperatively in the two groups were statistically analyzed. The postoperative complications and recurrent bleeding, as well as prognosis in the two groups, were recorded.ResultsThe operative time, hematoma evacuation rate, time to recovery of consciousness, postoperative GOS scores, time to extubation, and the length of hospital stay of the two groups were compared postoperatively, and the difference was statistically significant (p 0.05). The postoperative neurological function of the study group was lower than that of the control group, and the difference was statistically significant (P 0.05). The rate of pulmonary infections and gastrointestinal bleeding in the study group was lower than that of the control group, and the difference was statistically significant (P 0.05). The activities of daily living in the two groups were compared and the difference was statistically insignificant (p > 0.05).ConclusionModified transfrontal puncture drainage can effectively treat hypertensive basal ganglia hemorrhage patients and has relatively good safety.</p

Comparison of time intervals among ant experiments with six exit widths using the t-test.

<p>One, two, and three stars indicate a <i>P</i>-value below 0.05, 0.01, and 0.001, respectively. (A), (B), (C), (D), (E), and (F) show the results of comparisons between the exit widths 1<i>w</i> (0.5 cm), 2<i>w</i> (1.0 cm), 3<i>w</i> (1.5 cm), 4<i>w</i> (2.0 cm), 5<i>w</i> (2.5 cm), and 6<i>w</i> (3.0 cm), with each exit width being compared with every other exit width.</p

Green and gentle synthesis of Cu₂O nanoparticles using lignin as reducing and capping reagent with antibacterial properties

<div><p>In this work, Cu₂O nanoparticles of a particular shape were prepared by an eco-friendly, gentle and low-cost synthetic method using lignin as a reducing and capping reagent. Structure and morphology of the Cu₂O nanoparticles were characterised by high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction (XRD) and Fourier-transform (FT-IR) spectroscopy. The results established that Cu₂O nanoparticles coated by lignin showed a particular shape. The morphology of Cu₂O nanoparticles presented as some loose accumulation of particles just like broccoli, and the particle size range was between 100 and 200 nm. And, the XRD revealed the structure of crystalline of the Cu₂O nanoparticles. In addition, the sterilisation of Cu₂O nanoparticles on <i>Staphylococcus aureus</i> (<i>S. aureus</i>) and <i>Escherichia coli</i> (<i>E. coli</i>) was also investigated. The Cu₂O nanoparticles showed effective bactericidal activity against <i>E. coli</i> and <i>S. aureus</i>. The antibacterial rate could get 100% after 30 min with 4.0 g/L Cu₂O nanoparticles. Furthermore, the Cu₂O nanoparticles were confirmed to have low cytotoxicity.</p></div

Video recording of ants evacuating from a single-exit room.

<p>The exit width is 2<i>w</i> = 1.0 cm, and a 3.3% concentration of citronella was used.</p

Relationship between the value of <i>β</i> and the six different exit widths.

<p>The six exit widths were 1<i>w</i> (0.5 cm), 2<i>w</i> (1.0 cm), 3<i>w</i> (1.5 cm), 4<i>w</i> (2.0 cm), 5<i>w</i> (2.5 cm), and 6<i>w</i> (3.0 cm). The square represents the value of <i>β</i> for each exit width, and the solid line represents the result of linear fitting. A trend in which the value of <i>β</i> decreased as the exit width increased is evident.</p