Treesearch

Coupled fire-atmosphere models are increasingly being used to study low-intensity fires, such as those that are used in prescribed fire applications. Thus, the need arises to evaluate these models for their ability to accurately represent fire spread in marginal burning conditions. In this study, wind and fuel data collected during the Prescribed Fire Combustion and Atmospheric Dynamics Research Experiments (RxCADRE) fire campaign were used to generate initial and boundary conditions for coupled fire-atmosphere simulations. We present a novel method to obtain fuels representation at the...

A naturally occurring smart mycelium surface with tunable wettability is demonstrated. The commercially produced mycelium foam shows a natural hydrophobic and nonabsorbent surface with water contact angles well above 135°. The surface maintains its hydrophobicity and nonabsorbance after being compressed into a thin film under pressure and mild temperatures. We report that this surface carries tunable wettability. We have shown that a facile water treatment followed by room-temperature drying initially renders the surface highly hydrophilic and absorbent. Subsequent conditioning at 50 °C at...

The standard for calculating grade quality index (GQI) is a three-step process. First, failure codes are assigned during testing. Second, strength ratios are calculated from failure codes recorded during post-test analysis, not including failure from slope of grain. Third, the lower fifth percentile strength ratio is identified, which is defined as the GQI. In the past, the process of calculating strength ratios required one to correctly interpret and apply calculations per ASTM D4761 (current edition) and ASTM D245 (current edition) or gain remote access to USDA Forest Service, Forest...

February housing data indicated moderation in the U.S. housing market. Month-over-month data were mostly mixed; year-over-year data were predominantly positive, with the exceptions of total housing starts, multifamily starts, and multifamily housing under construction. New single-family and existing house sales were negative month-over-month and positive year-over-year. Single-family construction spending was positive month-over-month and year-over-year.

Vacuum kiln-drying, using low temperature in a low oxygen environment, produces light-colored hard maple in a significantly shorter drying time, and with less variability, than does conventional steam kiln-drying. To avoid chemical staining and to maintain light color, drying hard maple requires the use of high air flow at low temperature and relative humidity soon after being sawn. This study compared the color and drying times of hard maple dried in both types of kilns. Paired samples of 1-in. (25.4-mm) flat-sawn boards were dried in either a conventional kiln or a vacuum kiln, and...

Desarmillaria caespitosa, a North American vicariant species of European D. tabescens, is redescribed in detail based on recent collections from the USA and Mexico. This species is characterized by morphological features and multilocus phylogenetic analyses using portions of nuc rDNA 28S (28S), translation elongation factor 1-alpha (tef1), the second largest subunit of RNA polymerase II (rpb2), actin (act), and glyceraldehyde-3-phosphate dehydrogenase (gpd). A neotype of D. caespitosa is designated here. Morphological and genetic differences between D. caespitosa and D. tabescens were...

Key to the long-term resilience of dryland ecosystems is the recovery of foundation plant species following disturbance. In ecosystems with high interannual weather variability, understanding the influence of short-term environmental conditions on establishment of foundation species is essential for identifying vulnerable landscapes and developing restoration strategies. We asked how annual environmental conditions affect post-fire establishment of Artemisia tridentata, a shrub species that dominates landscapes across much of the western United States, and evaluated the influence of...

Cross-laminated timber (CLT) is a mass timber product that has recently garnered considerable attention for lateral-force resisting system (LFRS) applications. The main objectives of this study were to investigate the rocking behavior of a high-aspect-ratio (height/width) CLT shear wall without post-tensioning, and to validate a finite-element (FE) model based on the cyclic and dynamic response of the wall. To this point, high-aspect-ratio walls in the literature have primarily been post-tensioned. The testing component of this study included connector tests, quasistatic cyclic shear wall...

The potential of neat poly(lactic acid) (PLA) and PLA/cellulose nanocrystal (CNC) blown films in extending the shelf-life of crackers, a moisture-sensitive food product, was assessed. Product’s shelf-life, i.e., the time required by the crackers to reach its critical moisture content (CMC) of 8%, was determined experimentally from moisture content versus storage time plots at a constant temperature (25 °C) and various conditions of relative humidity (RH). Neither crackers within PLA nor PLA/CNC packages reached the CMC when stored below 50% RH at 25 °C, indicating that crackers packaged in...

Most existing functional diversity indices focus on a single facet of functional diversity. Although these indices are useful for quantifying specific aspects of functional diversity, they often present some conceptual or practical limitations in estimating functional diversity. Here, we present a new functional extension and evenness (FEE) index that encompasses two important aspects of functional diversity. This new index is based on the straightforward notion that a community has high diversity when its species are distant from each other in trait space. The index quantifies functional...