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We examined both the variation and the changing proportions of different wood products obtained from trees and logs in the Douglas-fir region of the northwestern United States. Analyses are based on a large product recovery database covering over 40 years of recovery studies; 13 studies are available for Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco). Visual lumber grades were combined into four broad value classes. We used the multinomial logistic model to estimate the yield proportion of each value class as a function of age, diameter, and their interaction. We also examine changes in wood product proportions with respect to future projections of forest management, harvesting trends, and sustainability. We see a clear shift away from appearance grades in the 1960s to construction grades by the late 1980s. This corresponds to a concomitant shift from high quality old-growth trees to young-growth plantations (age 50 to 60) of much smaller diameter. The projected relative proportions among the four product value classes is not expected to change much over current proportions; with construction lumber a dominant 70 to 80% of the total. Thus, we expect to remain at this new equilibrium, where very little appearance grade lumber is manufactured in the Douglas-fir region and price premiums have disappeared. [ABSTRACT FROM AUTHOR]

The Las VegasWash, which drains the Las Vegas valley watershed and provides the second largest inflow to Lake Mead, is being dramatically altered with erosion control structures and wetland restoration efforts. The impact of these changes on the cycling and distribution of Hg and Se is of particular interest because of their tendency to bioaccumulate and because of a lack of information on these contaminants in the Wash. In this study, we determined concentrations of Hg and Se in surface water (monthly), groundwater (once) and sediments (quarterly) from strategic locations within and along theWash during 2002 and 2003. The data was used to characterize Se sources and loading into theWash. Samples containing resurfacing groundwater and urban runoff (LW10.75 and Duck Creek) had significantly higher yearly means (13.7 ± 4.4 and 23.8 ± 4.1μg/L, respectively) compared with mainstream samples containing primarily treated wastewater (2.8 ± 0.8μg/L). Investigation of Se in tributaries, street runoff and rain suggest that the source of the elevated Se is likely groundwater seeps located within a relatively narrow geographic band on the southeast side of the valley. Se content of sediments was similar, except for LW10.75 which was rich in organic matter. Hg concentrations in the water and sediments were low, averaging 4±5 ng/L and 34±20 ng/g, dw, respectively. Overall, this study suggests that water quality remains relatively stable despite changes in theWash and managers of developing wetlands should not use tributary water as source water. [ABSTRACT FROM AUTHOR]

Shows that structurally distinct alpha-3-beta-4 nicotinic and P2X... channels influence each other when co-activated. Presentation of data which provides a molecular basis and a synaptic context for cross-inhibition between transmitter-gated cation channels; Methods; Results; Conclusion.

Presents a study which examined the hydrochemical data of major ions of groundwaters in Nevada and California in the United States. Review of related literature; Methods used; Results and discussion.

A facile template-free route has been employed to synthesize well-dispersed novel BiPO4 six-angular microcolumns with hierarchical architectures. The obtained products were characterized using XRD, EDX, and SEM. The experimental results indicate that the BiPO4 six-angular microcolumns are assembled by numerous nanoparticles in an oriented way. Additionally, the different solvent ratios have a significant influence on the morphology and crystal phase of the final products. [ABSTRACT FROM AUTHOR]

A convenient solvothermal route has been developed to synthesize flower-like Bi2O2CO3 architectures. The X-ray diffraction patterns confirm the body-centered tetragonal phase. The SEM and TEM images indicate that the flower-like Bi2O2CO3 architectures are assembled by numerous nanoplates. A self-assembly process is proposed to account for the formation of the obtained hierarchical structures. [ABSTRACT FROM AUTHOR]

The Chinese egret is a globally endangered species. Here we describe a set of primer pairs to amplify its entire mtDNA. The polymerase chain reaction products (1000–2000 bp) were successfully amplified by using this primer set and were then sequenced and aligned. The contiguous mtDNA sequences of the Chinese egret were assembled to be a circular molecule (17 579 bp). This primer set was also confirmed to be useful for six other species of ardeid birds. The versatility of this primer set will provide a groundwork for further studies on the genetic structure and molecular evolution of the ardeid species. [ABSTRACT FROM AUTHOR]

In this paper, a centre-fed, finite-length, infinitesimally thin dipole antenna is presented as a pressure sensor to monitor pressure changes in geotechnical engineering. The antenna consists of a liquid metal (eutectic gallium–indium alloy) injected in microfluidic channels, which are enclosed in the elastic material polydimethylsiloxane (PDMS); therefore, the liquid antenna is stretchable and frequency reconfigurable and can thus be used as a pressure sensor when the length of the elastic material PDMS is changed under pressure. The effects of the geometrical parameters of the dipole antenna on its resonant frequency are investigated using the finite-element software HFSS. Based on the numerical results, the liquid-metal antenna is designed, fabricated and measured, and its resonant frequencies are recorded under different pressures. According to the experimental results, the relation between the resonant frequency of the liquid antenna and the applied pressure is defined, and it is consistent with the numerical and theoretical results. Moreover, the experimental results show that the relation between the displacement and the resonant frequency is in good agreement with the numerical and theoretical results. Thus, there is a linear relation between the resonant frequency of the antenna and the applied pressure as well as between the resonant frequency and the displacement. Therefore, this frequency-reconfigurable liquid-metal dipole antenna is suitable for use as a pressure sensor. [ABSTRACT FROM AUTHOR]

[Objectives] A codominance functional marker of the broad-spectrum bacterial blight resistance gene, Xa7, of rice was identified for accurate detection, generation tracking, and differentiation between homozygous and hemizygous genotypes of the gene. [Methods] A potential functional marker containing four primer was designed using Premier 5 software and based on the differences on the sequences of Xa7, xa7, and allele-free genomes. The molecular distinctness of the marker in different materials was verified by PCR. Three crossbreed lines of Xa7 and their parents were inoculated with seven bacterial blight strains at the booting stage to examine the affected agronomic traits at maturation. [Results] The homozygous R084 of Xa7 could be amplified into a 91 bp band and the Nip free of allele with a 153 bp band, while the heterozygote Nip/R084, 91 bp and 153 bp bands. The candidate codominance marker, Xa7fun, amplified fragments that matched the predicted target bands. No 91 bp fragment was amplified from 18 germplasms of varied types, indicating a lack of Xa7 in them. Whereas Ry1, Ry2 and Ry3 had a 91 bp band, suggesting the inclusion of homozygous Xa7. Under an elevated temperature, Huazhan responded to the seven bacterial blight pathogens as highly susceptible % HS), intermediate susceptible % MS), or susceptible % S) ; R084 to six of the seven pathogens % HNA1-4, FuJ, GDA2, GD1358, PX086, and YN24) as highly resistant %HR), intermediate resistant % MR) or resistant % R) ; Ry-1 to five pathogens % GDA2, HNA1-4, FuJ, GD1358, and YN24) as HR or MR; Ry-2 to five pathogens % GDA2, GD1358, HNA1-, PX086, and YN24) asHRorR; and Ry-3 to 6 pathogens %HNA1-, FuJ, GDA2, GD1358, PX086, and YN24) as HR or MR. Therefore, the infiltration of Xa7 in the improved croosbred lines RY-1, RY-2, and RY-3 significantly accentuated the blight resistance of Huazhan. [ Conclusions] Homozygous or hemizygous Xa7 could be accurately differentiated by the currently identified codominance functional marker Xa7fun. The Xa7 introgression did not significantly alter the critical agronomic traits in the hybridization from generation to generation and could be safely applied in breeding rice varieties with bacterial blight resistance. [ABSTRACT FROM AUTHOR]

Allium cepa L.var. agrogatum Don. is one kind of Liliaceae plant and its extracts have been shown to have anti-inflammatory effect. In this study we investigated effect of the flavonoid constituents from Allium cepa L. var. agrogatum Don. on body fat and blood lipid profile of high fat diet-induced obese Wistar rats. The animals were divided to 4 groups (12/group) and fed control diet, high fat diet, high fat diet plus extract A, or high fat diet plus extract B for 15 d. Body weight, body fat, whole blood viscosity of low shear, medium shear and high shear, plasma viscosity, contents of triglycerides (TG), total cholesterol (TC), low density lipoprotein, and high density lipoprotein were determined. Results showed that the flavonoid constituents (both extract A and B) significantly visceral fat and extract B also significantly reduced decreased medium shear viscosity and low shear viscosity. No significant effect on blood lipid was observed. We conclude that the flavonoid constituents from Allium cepa L. var. agrogatum Don. may have an anti-obesity potential. [ABSTRACT FROM AUTHOR]

Behavioural flexibility may be a mechanism that confers resilience in the face of rapid environmental changes. However, behavioural flexibility is constrained by a number of factors, including physiology. Giant pandas, Ailuropoda melanoleuca, are an endangered ursid found in fragmented habitats at social densities far below their historical carrying capacity. Giant pandas use chemical, visual and acoustic signals to communicate during reproduction. Females are seasonally mono-oestrous, ovulate spontaneously and, thus, fertility and sexual receptivity are temporally constrained. However, because signalling behaviour is energetically costly, the ability to adjust signalling effort according to the presence of an appropriate receiver would be beneficial. Using female giant pandas at the Wolong Breeding Centre in Sichuan, China, we explored the interaction between social context and reproductive status on signalling and maintenance behaviours. To do so, we used linear mixed models and an information-theoretic approach to assess the temporal relationship between signalling behaviours and the timing of first mating. Our results show that signalling behaviour is correlated with time relative to first mating and that multimodal signalling was the best predictor of this timing. Furthermore, we found that social context also influenced signalling behaviours. Specifically, vocal and visual signalling effort were lower in the exclusive presence of other females, reducing the degree of wasted effort. Thus, in spite of the temporal constraints that spontaneous ovulation might impose on sexually proceptive and receptive behaviour, females can modify their behavioural efforts during the preovulatory period according to the prevailing social context. As an iconic endangered species, the giant panda may benefit from research that informs management. Our study provides information that can be applied to increase the success of conservation breeding efforts and their associated reintroduction programmes. [ABSTRACT FROM AUTHOR]

This study investigated the responses of 14 giant pandas (Ailuropoda melanoleuca) to 5 enrichment items (3 manipulable objects, 2 feeding devices) that possess different properties affording varying behavioral opportunities. Enrichment items were quantitatively described by using 12 properties. Pandas displayed no preferences among the 5 enrichment treatments, all of which had similar positive effects on behavioral measures of well-being (behavioral diversity, stereotypy). However, each item promoted a distinct behavioral profile, readily mapped onto the enrichment's properties. These results suggest that it may be important to stimulate behavioral diversity but that specific behaviors or enrichment properties are not required. The unique behavioral topography seen with these enrichments also suggests that providing multiple enrichments with varying properties will maximize overall behavioral diversity. [ABSTRACT FROM AUTHOR]

• Significant variation was found in the seasonal and annual litterfall biomass of the three types of forest stands. • The seasonal dynamics of litterfall biomass of twigs, leaf and fruits exhibited a 'unimodal pattern' with a peak in October. • Temperature played a key role in the climatic factors affecting forest litterfall processes. Litterfall is a link in the energy flow and material cycling of ecosystems, which maintain the primary productivity of forests. However, there is no consensus regarding the factors driving for the litterfall biomass dynamics because of the high spatial–temporal heterogeneity. Herein, we investigated and compared the stand litter biomass, litterfall biomass, including its components in the pure Robinia pseudoacacia forest (RL), pure Platycladus orientalis forest (PL), and mixed forest of Robinia pseudoacacia and Platycladus orientalis (ML) from 2020 to 2022 in the gully erosion area of the Loess Plateau. Correlation and multiple regression analyses were used to study the relationships among the amount of stand litter, litterfall biomass, and seasonal temperature and precipitation. Significant variation was found in the seasonal and annual litterfall biomass of the three types of forest stands. Annual stand litter biomass was in the order PL > RL > ML, whereas the annual litterfall biomass was in the order RL > ML > PL. The seasonal dynamics of litterfall biomass of twigs, leaf and fruits exhibited a 'unimodal pattern' with a peak in October. Annual leaf litterfall biomass formed, the main body of litter in all the components, accounting for 57.14–67.05 % of the total litterfall biomass. The correlation and regression analysis results showed that the stand litter biomass was primarily affected by the average temperature. Total litterfall biomass and twigs, leaf, and fruits were significantly affected by the precipitation and the maximum temperature, however, flower litterfall biomass was mainly affected by the average temperature. Overall, our results indicated that temperature plays a key role in the climatic factors affecting forest litterfall processes, while different climatic conditions and biological characteristics probably caused the differences in litterfall biomass. In the long term, temperature will potentially play a leading role in altering carbon storage and nutrient cycling as the climate warms. [ABSTRACT FROM AUTHOR]