RATIONALE Wood smoke-associated chronic obstructive pulmonary disease (COPD) is common in women in developing countries but has not been adequately described in developed countries. OBJECTIVES Our objective was to determine whether wood smoke exposure was a risk factor for COPD in a population of smokers in the United States and whether aberrant gene promoter methylation in sputum may modify ...

Plant functional traits capture important variation in plant strategy and function. Recent literature has revealed that within-species variation in traits is greater than previously supposed. However, we still have a poor understanding of how intraspecific variation is coordinated among different traits, and how it is driven by environment. We quantified intraspecific variation in wood density ...

Wood is one of the promising bioenergy feedstocks for lignocellulosic biofuel production. Understanding how wood components are synthesized will help us design strategies for better utilization of wood for biofuel production. One of the major wood components is xylan, in which about 10% of xylosyl residues are substituted with glucuronic acid (GlcA) side chains. All the GlcA side chains of xyla...

OBJECTIVE To describe and analyze clinical symptoms and spirometric alterations of patients with chronic obstructive pulmonary disease (COPD) and history of exposure to wood and tobacco smoke. METHODS We retrospectively evaluated data related to 170 patients distributed into 3 groups: 34 exposed only to wood smoke, 59 patients exposed only to tobacco smoke and 77 patients exposed to both. R...

1. Murray’s law states that the hydraulic conductance per blood volume of the cardiovascular system is maximized when the sum of the vessel radii cubed ( Σ r 3 ) is conserved. 2. We hypothesize that Murray’s law will apply to xylem conduits as long as they only transport water and do not also help support the plant. Specifically, the less volume of wood occupied by conduits, the more the condui...

This paper by Wood and Werkman is truly outstanding. First, it is a classical example of determination of the path of a fermentation by careful quantitative analyses of substrates consumed and products formed. Second and most importantly, the results led to the discovery of CO2 fixation by heterotrophic bacteria. The dogma at the time the work was done and as expressed in textbooks held that on...

the main objective of the present study was to explore the feasibility of nonlinear mixed models to describe the somatic cell score (scs) lactation curves and to compare the fit of four nonlinear vs. two linear models when applied to scs lactation records in iranian holstein cows. the animal breeding center of iran provided the scc data. the data consisted of 445077 test-day observations from 6...

Our concepts of the physical world distinguish objects, such as chairs, from substances, such as quantities of wood, that constitute them. A particular chair might consist of a single chunk of wood, yet we think about the chair and the wood in different ways. For example, part of the wood is still wood, but part of the chair is not a chair. In this article we examine the basis of the object/sub...

Lignocellulose forms the structural framework of woody plant biomass and represents the most abundant carbon source in the biosphere. Turnover of woody biomass is a critical component of the global carbon cycle, and the enzymes involved are of increasing industrial importance as industry moves away from fossil fuels to renewable carbon resources. Shipworms are marine bivalve molluscs that diges...

The cohesion-tension theory of water transport states that hydrogen bonds hold water molecules together and that they are pulled through the xylem under tension. This tension could cause transport failure in at least two ways: collapse of the conduit walls (implosion), or rupture of the water column through air-seeding. The objective of this research was to elucidate the functional significance...