University of Maine

About: University of Maine is a education organization based out in Orono, Maine, United States. It is known for research contribution in the topics: Population & Ice sheet. The organization has 8637 authors who have published 16932 publications receiving 590124 citations. The organization is also known as: University of Maine at Orono.

Cellulose Nanomaterials—Binding Properties and Applications: A Review

Abstract: Cellulose nanomaterials (CNs) are of increasing interest due to their appealing inherent properties such as bio-degradability, high surface area, light weight, chirality and the ability to form effective hydrogen bonds across the cellulose chains or within other polymeric matrices. Extending CN self-assembly into multiphase polymer structures has led to useful end-results in a wide spectrum of products and countless innovative applications, for example, as reinforcing agent, emulsion stabilizer, barrier membrane and binder. In the current contribution, after a brief description of salient nanocellulose chemical structure features, its types and production methods, we move to recent advances in CN utilization as an ecofriendly binder in several disparate areas, namely formaldehyde-free hybrid composites and wood-based panels, papermaking/coating processes, and energy storage devices, as well as their potential applications in biomedical fields as a cost-effective and tissue-friendly binder for cartilage regeneration, wound healing and dental repair. The prospects of a wide range of hybrid materials that may be produced via nanocellulose is introduced in light of the unique behavior of cellulose once in nano dimensions. Furthermore, we implement some principles of colloidal and interfacial science to discuss the critical role of cellulose binding in the aforesaid fields. Even though the CN facets covered in this study by no means encompass the great amount of literature available, they may be regarded as the basis for future developments in the binder applications of these highly desirable materials.

Pathogenesis and inflammatory response to Edwardsiella tarda infection in the zebrafish

Abstract: The zebrafish (Danio rerio) is a widely used model for developmental biology, neurobiology, toxicology, and genetic disease. Recently, the zebrafish has been recognized as a valuable model for infectious disease and immunity. In this study the pathogenesis and inflammatory cytokine response of zebrafish to experimental Edwardsiella tarda infection was characterized. In challenge experiments, zebrafish embryos were susceptible to infection by immersion. Adult fish were susceptible to challenge by intraperitoneal (ip) injection but not static immersion unless the epithelial layer was perturbed by scraping prior to exposure. To determine if E. tarda infection induces a typical acute inflammatory response, mRNA expression levels of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNFα) were assessed by quantitative real-time PCR. The expression levels of IL-1β and TNFα were significantly upregulated in infected zebrafish embryos and adults. The methods developed in this study will be particularly valuable for targeted gene disruption studies of host immune components and in zebrafish genetic screens.

Ecological Aspects of Methane Oxidation, a Key Determinant of Global Methane Dynamics

Abstract: Methane oxidation became a subject of scientific inquiry when Alessandro Volta observed in 1776 that gas bubbles collected from a pond were combustible. Methane was subsequently exploited as a source of heat and light. However, in spite of its commercial significance, the biological and ecological aspects of methane oxidation were largely ignored until the pioneering work of Sohngen (1906), who first isolated methane-oxidizing bacteria (MOB). [Quayle (1987) notes that Lowe probably isolated the first MOB in 1892 without recognizing their ability to oxidize methane.] Little additional progress was made until the 1960s, at which time the systematic efforts of several groups provided methodological tools and details on the taxonomy, physiology, and biochemistry of C1 metabolism. Aside from purely academic motivations, this work was stimulated by: (1) the potential use of methanotrophic bacteria as sources of “single cell protein”; (2) the role of methylotrophic bacteria in food spoilage; (3) the possible use of methanotrophs in the bioremediation of certain halogenated organic pollutants or as agents for commercial biotransformations (Higgins et al., 1980). Ecological studies were slower in development, but a number of important observations established the ubiquity of methanotrophs, the impact of methane oxidation in freshwater and some marine systems, and the potential for anaerobic as well as aerobic methane oxidation (see Hanson, 1980, and Rudd and Taylor, 1980, for earlier reviews).

Welfare Measurements Using Contingent Valuation: A Comparison of Techniques

Abstract: Three commonly used techniques of asking contingent valuation questions are compared: iterative bidding, payment cards, and dichotomous choice. The results reveal that no single contingent valuation technique is neutral in the elicitation of hicksian surplus and each technique has its strengths and weaknesses. The iterative bidding estimates contain a starting point bias, while the payment card and dichotomous choice estimates were influenced by the interviewers soliciting the contingent values. Finally, the analysis of dichotomous choice responses involves unresolved issues that warrant further investigation. On the other hand, dichotomous choice is the easiest technique to administer in a survey setting.

A new role for cryptochrome in a Drosophila circadian oscillator

Abstract: Cryptochromes are flavin/pterin-containing proteins that are involved in circadian clock function in Drosophila and mice. In mice, the cryptochromes Cry1 and Cry2 are integral components of the circadian oscillator within the brain and contribute to circadian photoreception in the retina. In Drosophila, cryptochrome (CRY) acts as a photoreceptor that mediates light input to circadian oscillators in both brain and peripheral tissue. A Drosophila cry mutant, cryb, leaves circadian oscillator function intact in central circadian pacemaker neurons but renders peripheral circadian oscillators largely arrhythmic. Although this arrhythmicity could be caused by a loss of light entrainment, it is also consistent with a role for CRY in the oscillator. A peripheral oscillator drives circadian olfactory responses in Drosophila antennae. Here we show that CRY contributes to oscillator function and physiological output rhythms in the antenna during and after entrainment to light-dark cycles and after photic input is eliminated by entraining flies to temperature cycles. These results demonstrate a photoreceptor-independent role for CRY in the periphery and imply fundamental differences between central and peripheral oscillator mechanisms in Drosophila.