bluuebunny/crossref_metadata_2025 huggingface dataset:
The Active Site Is the Least Stable Structure in the Unfolding Pathway of a Multidomain Cold-Adapted α-Amylase
Authors: Siddiqui Khawar S. , Feller Georges , D'Amico Salvino , Gerday Charles , Giaquinto Laura , Cavicchioli Ricardo
Published: August 2005

The cold-active α-amylase from the Antarctic bacterium
Pseudoalteromonas haloplanktis
(AHA) is the largest known multidomain enzyme that displays reversible thermal unfolding (around 30°C) according to a two-state mechanism. Transverse urea gradient gel electrophoresis (TUG-GE) from 0 to 6.64 M was performed under various conditions of temperature (3°C to 70°C) and pH (7.5 to 10.4) in the absence or presence of Ca
2+
and/or Tris (competitive inhibitor) to identify possible low-stability domains. Contrary to previous observations by strict thermal unfolding, two transitions were found at low temperature (12°C). Within the duration of the TUG-GE, the structures undergoing the first transition showed slow interconversions between different conformations. By comparing the properties of the native enzyme and the N12R mutant, the active site was shown to be part of the least stable structure in the enzyme. The stability data supported a model of cooperative unfolding of structures forming the active site and independent unfolding of the other more stable protein domains. In light of these findings for AHA, it will be valuable to determine if active-site instability is a general feature of heat-labile enzymes from psychrophiles. Interestingly, the enzyme was also found to refold and rapidly regain activity after being heated at 70°C for 1 h in 6.5 M urea. The study has identified fundamental new properties of AHA and extended our understanding of structure/stability relationships of cold-adapted enzymes.
Using Multilocus Sequence Data To Define the Pneumococcus
Authors: Hanage William P. , Kaijalainen Tarja , Herva Elja , Saukkoriipi Annika , Syrjänen Ritva , Spratt Brian G.
Published: August 2005

We investigated the genetic relationships between serotypeable pneumococci and nonserotypeable presumptive pneumococci using multilocus sequence typing (MLST) and partial sequencing of the pneumolysin gene (
ply
). Among 121 nonserotypeable presumptive pneumococci from Finland, we identified isolates of three classes: those with sequence types (STs) identical to those of serotypeable pneumococci, suggesting authentic pneumococci in which capsular expression had been downregulated or lost; isolates that clustered among serotypeable pneumococci on a tree based on the concatenated sequences of the MLST loci but which had STs that differed from those of serotypeable pneumococci in the MLST database; and a more diverse collection of isolates that did not cluster with serotypeable pneumococci. The latter isolates typically had sequences at all seven MLST loci that were 5 to 10% divergent from those of authentic pneumococci and also had distinct and divergent
ply
alleles. These isolates are proposed to be distinct from pneumococci but cannot be resolved from them by optochin susceptibility, bile solubility, or the presence of the
ply
gene. Complete resolution of pneumococci from the related but distinct population is problematic, as recombination between them was evident, and a few isolates of each population possessed alleles at one or occasionally more MLST loci from the other population. However, a tree based on the concatenated sequences of the MLST loci in most cases unambiguously distinguished whether a nonserotypeable isolate was or was not a pneumococcus, and the sequence of the
ply
gene fragment was found to be useful to resolve difficult cases.
An assessment of dermal exposure to semi-synthetic metal working fluids by different methods to group workers for an epidemiological study on dermatitis
Authors: van Wendel de Joode B , Bierman E P B , Brouwer D H , Spithoven J , Kromhout H
Published: August 2005

Background:Assessment of exposure assessment to metal working fluids (MWF) has almost exclusively focused on inhalation exposure.

Aims:To assess levels of, and factors affecting, dermal and inhalation exposure to semi-synthetic MWF, and to identify suitable dermal exposure grouping schemes among metal workers for an epidemiological survey on dermatitis of hands, forearms, and head.

Methods:A cross-sectional survey was conducted in four metal working machining departments of a truck manufacturing plant, estimating dermal and inhalation exposure levels to semi-synthetic metal working fluids (SMWF) in machine operators. Dermal exposure levels to SMWF were estimated by three different methods for dermal exposure assessment (VITAE, surrogate skin pad method, and a semi-quantitative dermal exposure assessment method (DREAM)).

Results:The identified factors affecting dermal exposure were similar for the three methods, although differences were found for estimated variability in dermal exposure levels between groups, within groups (among workers), and from day to day. With the VITAE method differences in exposure levels were detected between workers that were not detected with the surrogate skin pad method, and only partly with the DREAM method.

Conclusions:Considering the additional effort and costs that use of the VITAE method entailed, the observational semi-quantitative DREAM method appeared to be more efficient for grouping of dermal exposure levels for the epidemiological study on dermatitis.
The impact of overtime and long work hours on occupational injuries and illnesses: new evidence from the United States
Authors: Dembe A E , Erickson J B , Delbos R G , Banks S M
Published: August 2005

Aims:To analyse the impact of overtime and extended working hours on the risk of occupational injuries and illnesses among a nationally representative sample of working adults from the United States.

Methods:Responses from 10 793 Americans participating in the National Longitudinal Survey of Youth (NLSY) were used to evaluate workers’ job histories, work schedules, and occurrence of occupational injury and illness between 1987 and 2000. A total of 110 236 job records were analysed, encompassing 89 729 person-years of accumulated working time. Aggregated incidence rates in each of five exposure categories were calculated for each NLSY survey period. Multivariate analytical techniques were used to estimate the relative risk of long working hours per day, extended hours per week, long commute times, and overtime schedules on reporting a work related injury or illness, after adjusting for age, gender, occupation, industry, and region.

Results:After adjusting for those factors, working in jobs with overtime schedules was associated with a 61% higher injury hazard rate compared to jobs without overtime. Working at least 12 hours per day was associated with a 37% increased hazard rate and working at least 60 hours per week was associated with a 23% increased hazard rate. A strong dose-response effect was observed, with the injury rate (per 100 accumulated worker-years in a particular schedule) increasing in correspondence to the number of hours per day (or per week) in the workers’ customary schedule.

Conclusions:Results suggest that job schedules with long working hours are not more risky merely because they are concentrated in inherently hazardous industries or occupations, or because people working long hours spend more total time “at risk” for a work injury. Strategies to prevent work injuries should consider changes in scheduling practices, job redesign, and health protection programmes for people working in jobs involving overtime and extended hours.
Liming for the mitigation of acid rain effects in freshwaters: A review of recent results
Authors: Clair Thomas A , Hindar Atle
Published: August 2005

Acid rain has affected freshwater ecosystems for more than 50 years in much of northern Europe and North America. The acidification of waters, along with concurrent reduction in acid neutralization capacity, has caused deleterious changes to aquatic populations in much of these regions. To reverse some of the changes to aquatic ecosystems, a number of governmental and nongovernmental groups have applied lime and other neutralizing substances to streams, rivers, lakes, and catchments in the most affected or most ecologically valuable regions. We review the scientific literature published since the late 1980s on liming to provide an overview of successes and failures of various approaches. We discuss the rationale behind liming programs and why certain approaches may not be helpful in mitigating acidification effects under varying conditions. One of our main conclusions is that though water chemistry may be restored if only temporarily, aquatic communities probably will not return to their original states, though targeted fish species can be restored using active management approaches. The communities restored, however, are usually more unstable than those from undisturbed, or pre-acidification conditions. We also show that liming may have to be conducted for 50 to 60 years in some affected locations, which should affect the choice of approaches used in mitigation.Key words: acid rain, mitigation, liming, freshwaters, catchments, salmonids.
Eggs-per-recruit model for management of the California market squid (Loligo opalescens) fishery
Authors: Maxwell Michael R , Jacobson Larry D , Conser Ramon J
Published: August 2005

We develop a per-recruit model for the management of the California market squid (Loligo opalescens) fishery. Based on recent confirmation of determinate fecundity in this species, we describe how catch fecundity (i.e., eggs remaining in the reproductive tracts of harvested females) can be used to simultaneously infer fishing mortality rate along with management reference points such as yield-per-recruit, spawned eggs-per-recruit, and proportional egg escapement. Rates of mortality and egg laying have important effects on these reference points. Somewhat surprisingly, increasing the rate of natural mortality decreased spawned eggs-per-recruit while increasing proportional egg escapement. Increasing the rate of egg laying increased both spawned eggs-per-recruit and egg escapement. Other parameters, such as the maturation rate and gear vulnerability of immature females, affected the reference points. In actual practice, the influence of these parameters for immature squid may go undetected if immature squid are excluded from analysis of the catch. Application of this model to routine management is feasible but requires refinement of sampling procedures, biological assumptions, and model parameters. This model is useful because it is grounded on empirical data collected relatively inexpensively from catch samples (catch fecundity) while allowing for the simultaneous calculation of instantaneous fishing mortality rate and egg escapement.
Resource requirements of Asterionella formosa and Fragilaria crotonensis in oligotrophic alpine lakes: implications for recent phytoplankton community reorganizations
Authors: Saros Jasmine E , Michel Timothy J , Interlandi Sebastian J , Wolfe Alexander P
Published: August 2005

A widespread increase in the relative abundances of Asterionella formosa and Fragilaria crotonensis has occurred in oligotrophic alpine lakes across the western United States. Previous investigations have suggested that enhanced atmospheric nitrogen (N) deposition is driving these shifts in diatom community structure; however, little information is available on N requirements of these taxa. We examined the distributions of these two taxa in relation to a variety of physicochemical parameters in a suite of lakes situated in the Beartooth Mountain Range (MontanaWyoming, USA). We also conducted a series of nutrient enrichment experiments to assess the response of these taxa to changes in N, phosphorus (P), and silica (Si) supply. The distributions of both taxa were positively correlated with C:P, N:P, and Si:P seston ratios, revealing that these taxa are abundant when P availability is very low and the supply of N and Si are moderate to high. In the enrichment experiments, both taxa responded strongly to N additions, whereas P or Si enrichment alone had no effect. While these two taxa are indicative of P enrichment in temperate lakes, our results indicate that in these oligotrophic alpine lakes, N enrichment is driving their recent increase.
Structure and functioning of the eastern Scotian Shelf ecosystem before and after the collapse of groundfish stocks in the early 1990s
Authors: Bundy Alida
Published: August 2005

The fishery-induced collapse of the Atlantic cod (Gadus morhua) stock on the eastern Scotian Shelf has altered the species composition of this ecosystem. Ecopath mass-balance models of the ecosystem before and after the collapse were developed to explore how the structure, function, and key species of the ecosystem had changed. For the first time, an analysis of uncertainty was conducted to examine the effects of the uncertainty on model estimates. A comparison of the two Ecopath models indicated that although total productivity and total biomass of the ecosystem remained similar, there were changes in predator structure, trophic structure, and energy flow, many of which were robust to uncertainty. Biomass has significantly increased at trophic levels 3 and 4, and the composition of these trophic levels has changed as a result of the mean increase in trophic level of many species-groups. Piscivory has increased, presumably because of the high abundance of small pelagic fish, and the ratio of pelagic feeders to demersal feeders has increased from 0.3 to 3.0. Thus, the ecosystem has changed from a demersal-feeder-dominated system to a pelagic-feeder-dominated system. Although uncertainty remains concerning some model estimates, the ecosystem has been profoundly altered and exhibits classic symptoms of "fishing down the food web". However, overall system properties were generally conserved.
Can Atlantic cod (Gadus morhua) recover? Exploring trophic explanations for the non-recovery of the cod stock on the eastern Scotian Shelf, Canada
Authors: Bundy Alida , Fanning L Paul
Published: August 2005

The Atlantic cod (Gadus morhua) stock on the eastern Scotian Shelf collapsed in 1993. Over a decade later, in spite of a fisheries moratorium on cod fishing, this stock is at an all-time low. In parallel with the collapse of the cod stock, the abundance of large cod prey, including forage fish, shrimp, and snow crab, has greatly increased. The key question, which we explore using trophic mass-balance models, is what processes are preventing cod from recovering on the eastern Scotian Shelf? Cod were split into large and small cod. Modelling results indicate high predation pressure on small cod. In addition, small cod compete with the abundant forage fish for decreasing prey, and are in below-average condition. Large cod incur high, but unidentified, mortality that we suggest is derived from the poor condition of small cod carried through to adulthood. As a consequence of the removal of cod by fishing and an ensusing trophic cascade, eastern Scotian Shelf cod are trapped in a vicious circle: their abundance is being kept low by predation, causing an abundance so low that cod cannot compete for prey with their exceptionally abundant competitors. Furthermore, these competitors may also prey on younger stages of cod.
Multispecies modelling of some components of the marine community of northern and central Patagonia, Argentina
Authors: Koen-Alonso Mariano , Yodzis Peter
Published: August 2005

Using a bioenergetic and allometric approach, we developed multispecies trophodynamic models of the marine community of northern and central Patagonia in the southwestern South Atlantic Ocean that included hake (Merluccius hubbsi), squid (Illex argentinus), anchovy (Engraulis anchoita), and South American sea lions (Otaria flavescens). We used these to explore the effects of model structure and parameter uncertainty on predictions of the effects of different management regimes using continuation and bifurcation analysis. We considered five different functional responses and used the Akaike Information Criterion for model selection. The best models involved laissez-faire Holling Type III-shaped functional responses and the worst one corresponded to the Ecosim form. These models showed many similar behaviours but also showed marked differences in some exploitation scenarios. This suggests that using a single model structure as the basis for managing these stocks could lead to misleading, and potentially dangerous, conclusions.
Evaluation of fish-injury mechanisms during exposure to turbulent shear flow
Authors: Deng Zhiqun , Guensch Gregory R , McKinstry Craig A , Mueller Robert P , Dauble Dennis D , Richmond Marshall C
Published: August 2005

Understanding the factors that injure or kill turbine-passed fish is important to the operation and design of the turbines. Motion-tracking analysis was performed on high-speed, high-resolution digital videos of juvenile salmonids exposed to a laboratory-generated shear environment to isolate injury mechanisms. Hatchery-reared fall chinook salmon (Oncorhynchus tshawytscha, 93128 mm in length) were introduced into a submerged, 6.35-cm-diameter water jet at velocities ranging from 12.2 to 19.8 m·s1, with a reference control group released at 3 m·s1. Injuries typical of turbine-passed fish were observed and recorded. Three-dimensional trajectories were generated for four locations on each fish released. Time series of velocity, acceleration, force, jerk, and bending angle were computed from the three-dimensional trajectories. The onset of minor, major, and fatal injuries occurred at nozzle velocities of 12.2, 13.7, and 16.8 m·s1, respectively. Opercle injuries occurred at 12.2 m·s1nozzle velocity, while eye injuries, bruising, and loss of equilibrium were common at velocities of 16.8 m·s1and above. Of the computed dynamic parameters, acceleration showed the strongest predictive power for eye and opercle injuries and overall injury level, and it may provide the best potential link between laboratory studies of fish injury, field studies designed to collect similar data in situ, and numerical modeling.
A method to bin alleles of genetic loci that maintains population heterogeneity
Authors: Bromaghin Jeffrey F , Crane Penelope A
Published: August 2005

Fishery resources are often studied when individuals from multiple stocks are aggregated. For that reason, mixed-stock analysis (MSA), i.e., estimation of the stock composition of a mixture of individuals, is an important component of many research programs. Although many characteristics can be used in MSA, DNA loci, particularly microsatellites, have become extremely common. Microsatellite loci usually have a greater number of potential expressions, or alleles, than other marker types. A high degree of polymorphism can enhance the power of MSA, but allele proportions are estimated less precisely and rare alleles are absent or observed in very small numbers in typically sized samples. The reduced precision and presence of rare alleles can degrade the performance of some analytic methods. Although the effect can be reduced by binning alleles, which is common, an objective method of doing so has not been available previously. We present a method for binning alleles that reduces the number of rare alleles, largely preserves the genetic relationships observed among stocks, and modestly improves the performance of mixed-stock and individual-assignment analyses. The method is illustrated with data from Yukon River chum salmon (Oncorhynchus keta) and western Alaska Dolly Varden (Salvelinus malma).
Soft-X-ray spectra of highly charged Os, Bi, Th, and U ions in an electron beam ion trap
Authors: Träbert E , Beiersdorfer P , Fournier K B , Chen M H
Published: August 2005

Systematic variation of the electron-beam energy in an electron-beam ion trap has been employed to produce soft-X-ray spectra of Os, Bi, Th, and U with the highest charge states ranging up to Ni-like ions. Guided by relativistic atomic structure calculations, the strongest lines have been identified with Δn = 0 (n = 4 to n′ = 4) transitions in Rb- to Cu-like ions. The rather weak 4p4d transitions are much less affected by QED contributions than the dominant 4s4p transitions. Our wavelength measurements consequently provide benchmarks with and (almost) without QED. Because the radiative corrections are not very sensitive to the number of electrons in the valence shell, our data, moreover, provide benchmarks for the evaluation of electronelectron interactions. PACS Nos.: 32.30.Rj, 39.30.+w, 31.50.+w
Coarse woody debris in mid-aged stands: abandoned agricultural versus long-term forest land
Authors: Lõhmus Asko , Lõhmus Piret
Published: August 2005

During the 20th century, large agricultural areas in Eastern Europe became forested after their abandonment. To explore the value of these new forests for biota, we assessed volumes of coarse woody debris (CWD) on random transects in mid-aged (4075 years old) stands. In mixed and deciduous forests that were not forested in the 1930s, downed tree (log) volumes were about two times lower than in cutover sites. The effect on snag volume depended on site type and was generally nonsignificant. Large-diameter CWD showed similar proportions in the long-term and new forest areas, but large, well-decayed trunks tended to be less frequent in the latter. No reduction of dead wood volume was found in new pine stands, 98% of which had previously been classified as mires (bogs). Hence the origin of mid-aged successional forests had affected their CWD supply (particularly logs) to some extent, but the general scarcity of CWD all over the forest land indicated much larger (at least five-fold) losses due to timber harvesting. We conclude that naturally reforested areas should not be automatically excluded from reserve establishment or other CWD-related conservation programmes.
Response of plant functional groups within plantations and naturally regenerated forests in southern New Brunswick, Canada
Authors: Ramovs B V , Roberts M R
Published: August 2005

We examined the composition of understory vascular plant species in managed forests to determine how life-history attributes influence plant response to disturbance. Forest types investigated were plantations on old fields (3177 years old, n = 6), plantations on cutover land (1964 years old, n = 8), young forests naturally regenerated after clear-cutting (2766 years old, n = 6), and mature natural forests with no recent harvesting activity (80100 years old, n = 6). Species were categorized by habitat preference (forest, intermediate, disturbed), growth form (12 categories), and life form (15 categories). Forest-habitat species dominated both natural stand types, whereas disturbed-habitat species dominated both plantation types. Mature natural stands contained higher frequency and cover of many herb growth forms, and cutover plantations contained higher values for shrubs. Old-field plantations contained low values for all growth forms. Two life forms, geophytes and rosette hemicryptophytes, were not well represented in either plantation type. All plant functional groups were present in each stand type, suggesting that differences among stand types occur as shifts in the relative abundances of functional groups. We hypothesize that some species may be at risk of local extirpation in plantations because of their limited growth rates and reproductive characteristics.
Tree diameter distribution modelling: introducing the logitlogistic distribution
Authors: Wang Mingliang , Rennolls Keith
Published: August 2005

Johnson's SBdistribution is a four-parameter distribution that is transformed into a normal distribution by a logit transformation. By replacing the normal distribution of Johnson's SBwith the logistic distribution, we obtain a new distributional model that approximates SB. It is analytically tractable, and we name it the "logitlogistic" (LL) distribution. A generalized four-parameter Weibull model and the Burr XII model are also introduced for comparison purposes. Using the distribution "shape plane" (with axes skew2and kurtosis) we compare the "coverage" properties of the LL, the generalized Weibull, and the Burr XII with Johnson's SB, the beta, and the three-parameter Weibull, the main distributions used in forest modelling. The LL is found to have the largest range of shapes. An empirical case study of the distributional models is conducted on 107 sample plots of Chinese fir. The LL performs best among the four-parameter models.
Patterns and general characteristics of severe forest dieback from 1950 to 1995 in the northeastern United States
Authors: Auclair Allan ND
Published: August 2005

US national and state forest insect and disease surveys provide plentiful information on forest dieback. These data, however, have not been quantified and analyzed systematically to address outstanding questions on the etiology of dieback. This study quantified long-term (19501995) trends in the severity of dieback on Acer saccharum Marsh., Fraxinus spp., Betula spp., and Picea rubens Sarg. in US northern hardwoods. A numeric index (010 scale) of the severity and extent of dieback was applied using key words frequently found in the surveys. The 18 episodes identified showed considerable variability among species at the local scale, yet systematic, repetitive patterns of dieback at the scale of the region and multidecadal time frame. Six dieback characteristics were evident: episodes showed abrupt onset and subsidence, endured 13.6 years on average, were cyclical, with a frequency of 22.3 years between recurrence, and averaged about two-thirds of maximum possible severity. In contrast to the perception that dieback is happenstance and chaotic, this study supports the hypothesis that, by addressing issues of spatial scale and long-term population dynamics, coherent, generic patterns emerge that are cyclic and predictable. Limitations and advantages of the approaches were discussed in terms of meeting needs of the US Forest Health Monitoring Program for innovative approaches to the analysis of the voluminous field data being assembled nationwide. By developing a quantitative database, environmental correlation and modeling of dieback now become possible.
Armillaria species on small woody plants, small woody debris, and root fragments in red pine stands
Authors: Kromroy K W , Blanchette R A , Grigal D F
Published: August 2005

The incidence of Armillaria on small woody plants, small woody debris, and root fragments was estimated in red pine (Pinus resinosa Ait.) stands in northeastern Minnesota. Soil core samples 10 cm in diameter, and extending to a depth of either 16 or 25 cm, were collected from 13 stands belonging to three age-classes. Half of the youngest stands had been treated using herbicide. Mycelial fans or rhizomorphs of Armillaria were observed on 13% of the small woody plants and isolated from 8% of them. Including small woody debris and root fragments, 38% of 0–16 cm deep samples had Armillaria. Armillaria was observed on 3% and isolated from 1% of individual substrate units from 0 to 25 cm deep samples. Within a single stand, 0%–67% of the samples and 0%–9% of the individual units had evidence of Armillaria. All but one isolate were Armillaria ostoyae (Romagn.) Herink. Herbicide-treated and untreated red pine stands had similar Armillaria incidence, and there was a trend of incidence inversely related to stand age-class. Large numbers of small woody plants, woody debris, and root fragments were found in red pine stands; varying percentages of these substrates were contributing to the survival of Armillaria and could also be serving as sources of root disease inoculum.
Nitrogen mineralization and nitrification in a mixed-conifer forest in southern California: controlling factors, fluxes, and nitrogen fertilization response at a high and low nitrogen deposition site
Authors: Fenn Mark E , Poth Mark A , Terry Joseph D , Blubaugh Timothy J
Published: August 2005

Net fluxes of nitrogen (N) mineralization and nitrification were measured in situ on a monthly basis for 3 years at a high (HN) and low (LN) N deposition site in the San Bernardino Mountains, California. Mean N mineralization fluxes in the forest floor and top 10 cm of mineral soil were 19.0 and 59.8 kg N·ha–1·year–1 at LN and HN, respectively. Mean net nitrification fluxes were 11.2 and 55.9 kg N·ha–1·year–1 at LN and HN, respectively. Relative nitrification (the percent N mineralized that was nitrified) was generally lower under Pinus ponderosa Dougl. ex P. & C. Laws. (or Pinus jeffreyi Grev. & Balf.) canopies than under Quercus kelloggii Newb. or open canopies. The rate of net N mineralization was the key factor for predicting the rate of net nitrification. Fertilization with 50 and 150 kg N·ha–1 at LN significantly increased the rates of net mineralization and net nitrification. At HN fertilization had no significant effect on net nitrification. We conclude that at low-deposition sites increased nitrification occurs in the short term in response to added N, but that sustained elevated net nitrification is driven by the accumulation of N-enriched litter and soil organic matter in conjunction with chronic throughfall N deposition inputs.
The influence of canopy, sky condition, and solar angle on light quality in a longleaf pine woodland
Authors: Pecot Stephen D , Horsley Stephen B , Battaglia Michael A , Mitchell Robert J
Published: August 2005

Light transmittance estimates under open, heterogeneous woodland canopies such as those of longleaf pine (Pinus palustris Mill.) forests report high spatial and temporal variation in the quantity of the light environment. In addition, light quality, that is, the ratio of red to far-red light (R:FR), regulates important aspects of plant development including stem extension, specific leaf area, and seed germination. We conducted two experiments to document sources of variation in R:FR (using a LI-COR 1800 portable spectroradiometer with a cosine-corrected light sensor) in a 70- to 90-year-old natural longleaf pine woodland in southwest Georgia, USA. The first experiment compared instantaneous measurements of R:FR over a 3-day period (March) with annual estimates of canopy transmittance (using gallium arsenide phosphide photodiodes) across the range of observed overstory abundance. The second experiment examined the effect of wiregrass cover (above or below), sky condition (blue sky or overcast), and solar angle (four sampling periods between October and March) on R:FR using a multifactorial repeated measures design. We found that (1) R:FR was significantly (p < 0.0001) and strongly (R2 = 0.72) related to annual estimates of canopy transmittance (percent photosynthetic photon flux density, %PPFD); (2) R:FR and %PPFD showed significant negative relationships with increasing overstory stocking (R2 = 0.20, p = 0.028 for R:FR, and R2 = 0.87, p < 0.0001 for %PPFD); and (3) R:FR decreased with increasing solar angle from maximum zenith for the study site under blue skies, was greater under overcast skies (0.84 blue sky vs. 1.18 overcast sky), and decreased under wiregrass (Aristida stricta Michx.) canopies (1.10 above vs. 0.98 below).
A lightning fire occurrence model for Ontario
Authors: Wotton B M , Martell David L
Published: August 2005

Lightning strike, fire weather, and fire occurrence data were used to model (i) the probability that a lightning strike causes a sustainable ignition on the forest floor and (ii) the probability of an ignition being detected and reported to the fire management agency for each ecoregion in the province of Ontario. An index that tracks duff moisture content in very sheltered areas of a forest stand (near the tree boles) was the most significant predictor in each ignition model. The presence of positive cloud-to-ground lightning strikes was also found to have a significant and positive influence on the probability of ignition in most areas of the province with the exception of the far northwest. Weather conditions following a lightning storm influence the probability that a lightning strike causes a sustainable ignition. Models of the probability of detecting a fire ignited by lightning were also created for each of the ecoregions across Ontario. The form of these models varied somewhat among ecoregions, but contained an indicator of receptive surface fire spread conditions and an indicator of the dryness of the heavier fuels (the organic layer) in the forest floor.
Comparison of coniferous forest carbon stocks between old-growth and young second-growth forests on two soil types in central British Columbia, Canada
Authors: Fredeen Arthur L , Bois Claudette H , Janzen Darren T , Sanborn Paul T
Published: August 2005

Carbon (C) stocks were assessed for hybrid interior spruce (Picea glauca (Moench) Voss × Picea engelmannii Parry ex Engelm.)-dominated upland forests within the Aleza Lake Research Forest in central British Columbia, Canada. Four old-growth (141250 years old) and four young second-growth (<20 years old) forest plots were established on the two dominant soil texture types, coarse and fine, for a total of 16 plots. Mean total C stocks for old-growth stands ranged from 423 Mg C·ha1 (coarse) to 324 Mg C·ha1 (fine), intermediate between Pacific Northwest temperate forests and upland boreal forests. Total C was lower in second-growth stands because of lower tree (mostly large tree stem), forest floor, and woody debris C stocks. In contrast, old-growth forest-floor C stocks ranged from 78 Mg C·ha1 (coarse) to 35 Mg C·ha1 (fine), 2.9- and 1.2-fold higher than in corresponding second-growth stands, respectively. Woody debris C stocks in old-growth stands totaled 35 Mg C·ha1 (coarse) and 31 Mg C·ha1 (fine), 2.7- and 3.4-fold higher than in second-growth stands, respectively. Mineral soil C to 1.07 m depth was similar across soil type and age-class, with totals ranging from 115 to 106 Mg C·ha1. Harvesting of old-growth forests in sub-boreal British Columbia lowers total C stocks by 54%41%.
Effect of an Herbal Formula Containing Ganoderma lucidum on Reduction of Herpes Zoster Pain: A Pilot Clinical Trial
Authors: Hijikata Yasuyo , Yasuhara Akihiro , Sahashi Yuko
Published: August 2005

Administration of hot water extracts of a herbal formula containing Ganoderma lucidum, WTMCGEPP (Wisteria floribunda 0.38, Trapa natans 0.38, Miristica agrans 0.38, Coix lachryma-jobi 0.75, cultivated Ganoderma lucidum 0.75, Elfuinga applanata 0.38, tissue cultured Panax ginseng 0.3. and Punica granatum 0.38: numerals designate dry weight gram/dose), decreased herpes zoster pain for five Japanese patients suffering from shingles. Pain relief started within a few days of intake and was almost complete within 10 days. Two acute herpes zoster with manifestations including trigeminal nerve ophthalmia (both 74 years old), lower body zoster (70 years old), herpes zoster oticus (17 years old), and leg herpes (28 years old), responded quickly to treatment and no patient developed post-herpetic neuralgia (PHN) after more than one year of follow-up.
Association Between Tumor Necrosis Factor-α Gene Polymorphism and Sasang Constitution in Cerebral Infarction
Authors: Um Jae-Young , Lee Jae-Heung , Joo Jong-Cheon , Kim Kyung-Yo , Lee Eun-Hee , Shin Taekyun , Hong Seung-Heon , Kim Hyung-Min
Published: August 2005

During the last decade, a growing corpus of evidence has indicated an important role of cytokines in the development of brain damage following cerebral ischemia. Tumor necrosis factor-α (TNF-α), a potent immunomodulator and pro-inflammatory cytokine, has been implicated in many pathological processes. In this study, we examined whether promoter region polymorphism in the TNF-α gene at position –308 affects the odds of cerebral infarction (CI) and whether genetic risk is enhanced by Sasang constitutional classification. Two hundred and twelve CI patients and 610 healthy controls were genotyped and determined according to Sasang constitutional classification. A significant decrease was found for the TNF-α A allele in CI patients compared with controls ( p = 0.033, odds ratio, OR: 0.622). However, there was no significant association between TNF-α polymorphism and Sasang constitution in CI patients. Our finding suggests that TNF-α promoter region polymorphism is responsible for susceptibility to CI in Koreans.
Nonlinear Analysis of Heart Rate Variability During Qi Therapy (External Qigong)
Authors: Lee Myeong Soo , Rim Young Hoon , Jeong Dong-Myong , Kim Mo Kyung , Joo Min Cheol , Shin Sun Ho
Published: August 2005

Heart rate variability (HRV) was compared in 30 subjects receiving external Qi therapy (EQT) or placebo control therapy, in a crossover design experiment. Subjects who received the EQT reported more pleasant and calm emotions than did the placebo group. Qi therapy reduced the heart rate and increased HRV as indicated by a reduced low frequency/high frequency power ratio of HRV. With nonlinear analysis, the Poincaré plot index of HRV and approximate entropy was greater in the EQT group than in the control group. These findings suggest that EQT stabilizes the sympathovagal function and cardiac autonomic nervous system by inducing more positive emotions than the placebo therapy. In conclusion, EQT may act by stabilizing both the autonomic nervous system and the emotional state.
A Birdcage Model for the Chinese Meridian System Part III: Possible Mechanism of Magnetic Therapy
Authors: Yung Kaung-Ti
Published: August 2005

Based on the electromagnetic model of the transmission line for the channel and the birdcage resonator for the meridian network, we interpret two effects, seemingly incomprehensible in terms of current Western physiology, the lasting effect and the remote effect. For the lasting effect, acupuncture enhances the amplitude of the Qi standing wave, and this increased amplitude is retained and thus is able to sustain a gradual remodeling of the extracellular matrix in interstitial connective tissues, resulting in a lasting therapeutic effect. For the remote effect (acupuncture effect far from the site of needle insertion), our model puts the mechanism of magnetic therapy on an equal footing with that of acupuncture. It may not be a coincidence that accounts of investigators in both acupuncture and magnetotherapy about the depth of the effective site — along cleavage planes between muscles, or between muscle and bone or tendon — are in accord with that of the Huang Di Nei Jing about the course of channels: "they are embedded and travel between interstitial muscles, deep and invisible." A possible magnetic field generated outside the birdcage may be manipulated to produce local areas of higher temperature or very strong fields.
Gastrodia elataBL Mediates the Suppression of nNOS and Microglia Activation to Protect Against Neuronal Damage in Kainic Acid-Treated Rats
Authors: Hsieh Ching-Liang , Chen Chi-Long , Tang Nou-Ying , Chuang Chin-Min , Hsieh Ching-Tou , Chiang Su-Yin , Lin Jaung-Geng , Hsu Sheng-Feng
Published: August 2005

Our previous studies showed that Gastrodia elata (GE), an herb used in traditional Chinese medicine, has both anti-convulsive and free radical-scavenging activities in kainic acid (KA)-treated rats. The aim of the present study was to further investigate possible physiological mechanisms of GE against activities of neuronal nitric oxide synthase (nNOS) and microglia in KA-treated rats; 0.5 g/kg and 1.0 g/kg of GE extract were administered orally, whereas 20 mg/kg of N-nitro-L-arginine methyl ester (L-NAME) was administered intraperitoneally (ip), both at 30 minutes prior to KA (2 μg/2 μl) being injected into the right hippocampus region of rats. ED1-staining, apoptotic, inducible nitric oxide synthase (iNOS), and nNOS-staining cells were observed in the hippocampus region. The results indicated that 1.0 g/kg of GE and 20 mg/kg of L-NAME reduced the counts of ED1-stained cells, and 0.5 g/kg and 1.0 g/kg of GE, and 20 mg/kg of L-NAME reduced the numbers of apoptotic cells and nNOS-staining cells. In addition, 20 mg/kg of L-NAME also reduced the numbers of iNOS-staining cells, but 0.5 g/kg and 1.0 g/kg of GE did not. This study demonstrated that GE was able to reduce nNOS, microglia activation and apoptosis, suggesting that GE has a protective effect against neuronal damage in KA-treated rats.
Hepatoprotection of Oleanolic Acid is Related to Its Inhibition on Mitochondrial Permeability Transition
Authors: Tang Xin-Hui , Gao Jing , Fang Feng , Chen Jin , Xu Li-Zhi , Zhao Xiao-Ning , Xu Qiang
Published: August 2005

The protective effects of oleanolic acid (OA) on carbon tetrachloride (CCl4)-induced liver mitochondrial damage and the possible mechanisms were investigated. Pretreatment with OA prior to the administration of CCl4 significantly suppressed the increases of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) (4.2- and 19.9-fold, respectively) in a dose-dependent manner in mice. The dissipation of mitochondrial membrane potential (14.8%) and intra-mitochondrial Ca 2+ overload (2.1-fold) in livers of CCl4-insulted mice were also dose-dependently prevented by pretreatment with 20, 50 or 100 mg/kg OA. In addition, the effects of OA on liver mitochondria permeability transition (MPT) induced by Ca 2+ were assessed by measuring the change in mitochondrial membrane potential, release of matrix Ca 2+ and mitochondrial swelling in vitro. The results showed that preincubation with 50 or 100 μg/ml OA obviously inhibited the Ca 2+-induced mitochondrial swelling, mitochondrial membrane depolarization and intra-mitochondrial Ca 2+ release. It could be concluded that OA has protective effects on liver mitochondria and the mechanisms underlying its protection may be related to its inhibitory action on MPT.
Effect of the Chinese Traditional Medicine "Bushen Yinao Pian" on the Cerebral Gene Expression of the Senescence-Accelerated Mouse Prone 8/Ta
Authors: Zhang Chong , Wang Jingang , Liu Guisheng , Chen Qingxuan
Published: August 2005

The effect of Chinese traditional medicine "Bushen Yinao Pian," a complex prescription used for anti-aging, on the cerebral gene expression of the senescence-accelerated mouse prone 8/Ta (SAMP8/Ta) had been studied with messenger ribonuclear acids reverse transcription differential display polymerase chain reaction (mRNA DDRT-PCR). Eight differential displayed bands had been discerned and sequenced. The sequences of those fragments are matched to adipocyte-specific protein-5; low density lipoprotein receptor-related protein associated protein-1; reticulon-3; cysteine and histidine-rich domain (CHORD)-containing, zinc-binding protein-1; cytochrome c oxidase subunit-2 (Cox-2); cytochrome c gene, MC1; DNA sequence from clone RP23-72M11 on chromosome X, respectively and a novel sequence fragment. Most of these genes are aging-related. It can be proved that the "Bushen Yinao Pian" truly has anti-aging function.
STUDY OF THE FUNDAMENTAL STRUCTURE OF MATTER WITH AN ELECTRON-ION COLLIDER
Authors: Deshpande Abhay , Milner Richard , Venugopalan Raju , Vogelsang and Werner
Published: August 2005

▪ Abstract  We present an overview of the scientific opportunities that would be offered by a high-energy electron-ion collider. We discuss the relevant physics of polarized and unpolarized electron-proton collisions and of electron-nucleus collisions. We also describe the current accelerator and detector plans for a future electron-ion collider.

This review is dedicated to the memory of Professor Vernon W. Hughes.
PHYSICS OF ULTRA-PERIPHERAL NUCLEAR COLLISIONS
Authors: Bertulani Carlos A. , Klein Spencer R. , Nystrand Joakim
Published: August 2005

▪ Abstract  Moving highly-charged ions carry strong electromagnetic fields that act as a beam of photons. In collisions at large impact parameters, hadronic interactions are not possible, and the ions interact through photon-ion and photon-photon collisions known as ultra-peripheral collisions (UPCs). Hadron colliders like the Relativistic Heavy Ion Collider (RHIC), the Tevatron, and the Large Hadron Collider (LHC) produce photonuclear and two-photon interactions at luminosities and energies beyond that accessible elsewhere; the LHC will reach a γp energy ten times that of the Hadron-Electron Ring Accelerator (HERA). Reactions as diverse as the production of anti-hydrogen, photoproduction of the ρ0, transmutation of lead into bismuth, and excitation of collective nuclear resonances have already been studied. At the LHC, UPCs can study many types of new physics processes.
LEPTOGENESIS AS THE ORIGIN OF MATTER
Authors: Buchmüller W. , Peccei R.D. , Yanagida T.
Published: August 2005

▪ Abstract  We explore in some detail the hypothesis that the generation of a primordial lepton-antilepton asymmetry (Leptogenesis) early on in the history of the Universe is the root cause for the origin of matter. After explaining the theoretical conditions for producing a matter-antimatter asymmetry in the Universe we detail how, through sphaleron processes, it is possible to transmute a lepton asymmetry—or, more precisely, a (B – L)-asymmetry—into a baryon asymmetry. Because Leptogenesis depends in detail on properties of the neutrino spectrum, we review briefly existing experimental information on neutrinos as well as the seesaw mechanism, which offers a theoretical understanding of why neutrinos are so light. The bulk of the review is devoted to a discussion of thermal Leptogenesis, and we show that for the neutrino spectrum suggested by oscillation experiments, one obtains the observed value for the baryon to photon density ratio in the Universe, independently of any initial boundary conditions. In the latter part of the review we consider how well Leptogenesis fits with particle physics models of dark matter. Although axionic dark matter and Leptogenesis can be very naturally linked, there is a potential clash between Leptogenesis and models of supersymmetric dark matter because the high temperature needed for Leptogenesis leads to an overproduction of gravitinos, which alter the standard predictions of Big Bang Nucleosynthesis. This problem can be resolved, but it constrains the supersymmetric spectrum at low energies and the nature of the lightest supersymmetric particle (LSP). Finally, as an illustration of possible other options for the origin of matter, we discuss the possibility that Leptogenesis may occur as a result of non-thermal processes.
THE ASSOCIATION OF NHERF ADAPTOR PROTEINS WITH G PROTEIN–COUPLED RECEPTORS AND RECEPTOR TYROSINE KINASES
Authors: Weinman Edward J. , Hall Randy A. , Friedman Peter A. , Liu-Chen Lee-Yuan , Shenolikar Shirish
Published: August 2005

▪ Abstract  The sodium-hydrogen exchanger regulatory factors (NHERF-1 and NHERF-2) are a family of adaptor proteins characterized by the presence of two tandem PDZ protein interaction domains and a C-terminal domain that binds the cytoskeleton proteins ezrin, radixin, moesin, and merlin. The NHERF proteins are highly expressed in the kidney, small intestine, and other organs, where they associate with a number of transporters and ion channels, signaling proteins, and transcription factors. Recent evidence has revealed important associations between the NHERF proteins and several G protein–coupled receptors such as the β2-adrenergic receptor, the κ-opioid receptor, and the parathyroid hormone receptor, as well as growth factor tyrosine kinase receptors such as the platelet-derived growth factor receptor and the epidermal growth factor receptor. This review summarizes the emerging data on the biochemical mechanisms, physiologic outcomes, and potential clinical implications of the assembly and disassembly of receptor/NHERF complexes.