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The COVID-19 pandemic has refocused research on mathematical modeling and analysis of epidemic dynamics. We analytically investigate a partial differential equation (PDE) based, compartmental model of spatiotemporal epidemic spread, marked by strongly nonlinear infection forces representing the infection transmission mechanism. Employing higher-order perturbation analysis and computing the local Lyapunov exponent, we observe the emergence of dynamic instabilities induced by stochastic environmental forces driving the epidemic spread. Notably, the instabilities are uncovered using third-order perturbations whilst they are not observed under second-order perturbations. Moreover, the onset of instability is more likely with increasing noise strength of the stochastic environmental forces.

Thin-film coatings have the capability of obtaining a wide range of thermal radiative properties, but the development of thin-film coatings can sometimes be difficult and costly when trying to achieve highly specular surfaces. Given any space mission’s thermal control requirements, there is often a need for a variation of solar absorptance (αs), emittance (∊) and/or highly specular surfaces. The utilization of thin-film coatings is one process of choice for meeting challenging thermal control requirements because of its ability to provide a wide variety of αs/∊ ratios. The radiative properties of thin-film coatings can be tailored to meet specific thermal control requirements through the use of different metals and the variation of dielectric layer thickness. Surface coatings can be spectrally selective to enhance radiative coupling and decoupling. The application of lacquer to a surface can also provide suitable specularity for thin-film application without the cost and difficulty associated with polishing.

A stress questionnaire was developed and administered to employees and students participating in a stress program. The questionnaire consists of three components: stressful conditions, stress symptoms, and measures used to relax. The present study focused on the validation of the stressful conditions portion. Factor analysis demonstrated that the questionnaire had three meaningful factors. Based on the analysis, composite scores were obtained reflecting these three dimensions. Alpha reliability analysis demonstrated that each of the factors was reliable at an acceptable level (r > .80). The first factor represented an organizational or external cluster, while the second factor reflected an internal or personal construct. The first factor was shown to correlate negatively with fatigue, worry, agitation, impatience, anger and similar symptoms, while the second factor correlated positively with these complaints. Studies of group differences revealed that defined occupational groups differed on scores for all portions of the questionnaire. In addition, groups participating in a stress management course changed significantly on the first two factors. The third factor related to handling conflict and contained only a few items. Replication studies showed that the factors were stable across different versions of the scales with different groups. The results suggest that the assessment method may be promising for future studies on stress management.

The presence of ergotoxine affects the action of ergonovine differently in different species.

The article offers information on the upgrade of theaters in the U.S. with reclining seats and in-theater food service. It mentions that the AMC Theatres is replacing seats in some of its U.S. theaters with La-Z-Boy-style recliners, food and drinks service to customers at their seats offered by Showcase Cinemas and Alamo Drafthouse Cinema, and change in auditoriums. It presents quiz concerning the theatres in the U.S.

A variety of plants synthesize natural products that either kill or inhibit the growth of various microorganisms. These plant products may serve as useful natural alternatives to synthetic antimicrobial pharmaceuticals and can be especially important in regions where commercial drugs are often not available. Despite this, the role of plants as producers of natural antimicrobial agents is often understated or even ignored in undergraduate biology curricula. In this laboratory exercise, students extract water-soluble constituents from two plants, Moringa oleifera(moringa) and Allium sativum(garlic), and determine their activity against both a gram-positive (Bacillus cereusstrain 971) and a gram-negative (Escherichia colistrain K12) bacterium using a disk diffusion assay on Mueller-Hinton agar. Disks infused with commercially available antibiotics (e.g., penicillin and tetracycline) serve as controls. Following an incubation period of 24 hours, students obtain quantitative data by measuring zones of growth inhibition that develop as a result of strain sensitivity. To determine the effectiveness of the learning objectives, an unannounced quiz was administered both before and after the activity, and the students showed significant gains in their understanding of key concepts. Because this activity combines aspects of two major branches of biology—plant biology and microbiology—it is suitable for use as a laboratory exercise in courses related to either discipline, or it may be used as a laboratory component of a general biology course.

The article looks at the improvements made on some movie theaters in the U.S. Topics include AMC Theatres' replacement of bucket seats in its theaters with La-Z-Boy-style recliners which can be reserved online, Showcase Cinemas and Alamo Drafthouse Cinema's serving of premium food and drinks to customers at their seats and Starplex Cinemas' installation of D-BOX motion seating in select theaters.

The article discusses the immigration law in Arizona and the U.S. federal government's lawsuit.

“Consider this…” is a feature designed to give you quick access to innovative ideas, research findings, interesting solutions to common problems, and more from a variety of sources. For the busy nurse executive, JONA asks you to “Consider this….”

The article provides information on the proposal of several bills in the 110th Congressional session concerning the immigration service and policy in the U.S. Under a new merit-based system, it stated that points will be awarded to employees based on education, occupation, family ties, English and civics knowledge. Moreover, the Senate and President George W. Bush have proposed various versions of a guest worker program that require the completion of certain enforcement and border security.