bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spatial distribution and temporal variation of Microcystis species composition and microcystin concentration in Lake Biwa
Authors: Ozawa Kazuhiko , Fujioka Hiroki , Muranaka Minoru , Yokoyama Atsushi , Katagami Yukimi , Homma Takamitsu , Ishikawa Kanako , Tsujimura Shigeo , Kumagai Michio , Watanabe Mariyo F. , Park Ho‐Dong 
Published: May 2005

AbstractSpatial and temporal variation in Microcystis species composition and microcystin concentration, quantified by enzyme‐linked immunosorbent assay and high‐performance liquid chromatography, were investigated during a 3‐year period (1998–2000) in the Northern Basin of Lake Biwa. The Northern Basin generally had a concentration of 5 μg L−1 or less, except at station 1 (Nagahama Bay) from July to October during the study period. The maximum concentration at station 1 was 22.7, 35.9, and 22.0 μg L−1 in October of 1998, 1999, and 2000, respectively. Eleven species of cyanobacteria were observed: Microcystis aeruginosa, M. ichthyoblabe, M. novacekii, M. wesenbergii, Oscillatoria raciborskii, Anabaena oumiana, A. affinis, A. flos‐aquae, A. ucrainica, A. smithii, and A. crassa. Of these, M. aeruginosa and M. wesenbergii were the main components observed. A high concentration of microcystin in the lake water was mostly a result of variation in the relative amount of toxic M. aeruginosa rather than of the total Microcystis cell number. This was supported by the analytical results for isolated strains. Microcystis spp. cell density in the Northern Basin appeared to increase gradually over the course of the study. This is the first study to have surveyed the Northern Basin of Lake Biwa, which supplies drinking water to 14 million people and is the largest lake in Japan. © 2005 Wiley Periodicals, Inc. Environ Toxicol 20: 270–276, 2005.
Organ distribution and bioaccumulation of microcystins in freshwater fish at different trophic levels from the eutrophic Lake Chaohu, China
Authors: Xie Liqiang , Xie Ping , Guo Longgen , Li Li , Miyabara Yuichi , Park Ho‐Dong 
Published: May 2005

AbstractThis article reports the organ distribution and bioaccumulation of hepatotoxic microcystins (MCs) in freshwater fishes at different trophic levels from the large, shallow, eutrophic Lake Chaohu in September 2003, when there were heavy surface blooms of toxic cyanobacteria. Among all fish, intestines and blood had the highest average content of MC‐RR + MC‐LR (22.0 and 14.5 μg g−1 DW, respectively), followed by liver, bile, and kidney (7.77, 6.32, and 5.81 μg g−1 DW, respectively), whereas muscle had the least (1.81 μg g−1 DW). MC content in muscle was highest in carnivorous fish (Culter ilishaeformis, 2.22 μg g−1 DW) and omnivorous fish (Carassius auratus, 1.96 μg g−1 DW) and was lowest in phytoplanktivorous fish (Hypophthalmichthys molitrix, 1.65 μg g−1 DW) and herbivorous fish (Parabramis pekinensis 0.660 μg g−1 DW). However, the amount of MC in the gut of H. molitrix (137 μg g−1 DW) was more than 20 times that in the other fish (<6.50 μg g−1 DW). The MCs showed a tendency to accumulate up the food chain, and piscivorous fish at the top of the food chain were at high risk of exposure to MCs in Lake Chaohu. Our study is the first to report MC concentrations in the bile and blood of wild fish. One hundred grams of fish muscle would contain 2.64–49.7 μg of MC‐LR equivalent, or about 1.3–25 times the recommended tolerable daily intake of MC‐LR by humans, indicating that fish are already severely contaminated by MCs and that the local authorities should warn the public of the risk of poisoning by eating the contaminated fish. © 2005 Wiley Periodicals, Inc. Environ Toxicol 20: 293–300, 2005.
Activity and substrate specificity of cytosolic and microsomal glutathione S‐transferase in Australian black tiger prawns (Penaeus monodon) after exposure to cyanobacterial toxins
Authors: Pflugmacher Stephan , Wiegand Claudia , Werner Stephanie , Schröder Helge , Kankaanpää Harri 
Published: May 2005

AbstractCyanobacterial toxins have been shown to have a far‐reaching impact—from aquatic organisms to human health. Aquatic organisms are typically exposed in their natural environment to toxic cyanobacteria, and exposure can occur via ingestion of cyanobacterial cells or by bioaccumulation of water‐borne toxin. The aquaculture and fisheries of crustaceans are among the most important seafood industries. Concomitant with the growth of this industry, the importance of the health of crustaceans increased. The black tiger prawn is the major cultivated prawn in Australia. The aquaculture of these prawns takes place in shallow ponds, where blooms, often of cyanobacteria, develop. Cyanobacterial toxins were hypothesized to contribute to the mortality of prawns. Many aquatic organisms have the possibility of detoxifying cyanobacterial toxins via conjugation to glutathione. The presence of several classes of the cytosolic glutathione S‐transferase system in black tiger prawns—mu, pi, theta, alpha, and tau—was shown using different substrates for measurement. Injection experiments with microcystin‐LR and feeding experiments with nodularin revealed elevation of GST activity in different types of prawn tissue in parallel with reduction in the GST classes. Correlation analyses of toxin content of the prawns with GST activity showed that low toxin content was correlated with high elevation of enzymes and high toxin content with low elevation of enzymes. © 2005 Wiley Periodicals, Inc. Environ Toxicol 20: 301–307, 2005.
Microcystin‐RR uptake and its effects on the growth of submerged macrophyte Vallisneria natans (lour.) hara
Authors: Yin Liyan , Huang Jiaquan , Li Dunhai , Liu Yongding 
Published: May 2005

AbstractMicrocystins are hepatotoxins produced by many species of several cyanobacterial genera. Their toxic effects on animals and some terrestrial higher plants have been well studied, but their potential effects on the development of aquatic plant seedlings are not well known, and their uptake by aquatic plants is seldom reported. In our research the seeds and seedlings of the submerged macrophyte Vallisneria natans were exposed to different concentrations of microcystin‐RR, which was purified with high‐performance liquid chromatography (HPLC). The results indicated that microcystin‐RR could accumulate differentially in the roots and leaves of V. natans seedlings. Toxin accumulation in the roots and leaves was time‐ and dose‐dependent, with higher uptake detected in the roots. Growth and development detection revealed that V. natans was relatively insensitive to microcystin‐RR at concentrations ranging from 0.0001 to 0.01 mg/L. However, when the toxin concentration was more than 0.01 mg/L, both the fresh weight and the longest leaf length of seedlings were significantly reduced after a 30‐day treatment. The root and leaf numbers were significantly decreased when 10 mg/L of toxin was used. These results suggest that microcystin‐RR can be taken up by V. natans, which subsequently will retard its development. © 2005 Wiley Periodicals, Inc. Environ Toxicol 20: 308–313, 2005.
Second order parabolic systems, optimal regularity, and singular sets of solutions
Authors: Mingione Giuseppe , Duzaar Frank 
Published: May 2005

We present a new, complete approach to the partial regularity of solutions to non-linear, second order parabolic systems of the form

u_{t}−\mathrm{div}A(x,t,u,Du) = 0.

In the first part we introduce the

A

-caloric approximation lemma, a parabolic analogue of the harmonic approximation lemma of De Giorgi [Sem. Scuola Normale Superiore Pisa (1960–1961); Lectures in Math., ETH Zürich, Birkhäuser, Basel, 1996] in the version of Simon. This allows to prove optimal partial regularity results for solutions in an elementary way, under minimal and natural assumptions. In the second part we provide estimates for the parabolic Hausdorff dimension of the singular sets of solutions; the proof makes use of parabolic fractional Sobolev spaces.

Résumé
Nous présentons une nouvelle approche complète auprès de la regularité partielle des solutions des systèmes paraboliques, non-linéaires, de la deuxième ordre de la forme

u_{t}−\mathrm{div}A(x,t,u,Du) = 0.

Dans une première partie nous introduisons le lemme d'approximation

A

-calorique, un analogue parabolique du lemme d'approximation harmonique de De Giorgi [Sem. Scuola Normale Superiore Pisa (1960–1961) ; Lectures in Math., ETH Zürich, Birkhäuser, Basel, 1996] d'après la version Simon. Cela permet de prouver des résultats optimales de la regularité partielle pour des solutions d'une façon elementaire sous des hypothèses minimales et naturelles. Dans la deuxième partie nous donnons des estimations des ensembles singuliers des solutions pour la dimension parabolique de Hausdorff ; la preuve se sert des espaces paraboliques fractionnaires de Sobolev.
Role change of design engineers in product development
Authors: Hong Paul , Vonderembse Mark A. , Doll William J. , Nahm Abraham Y. 
Published: May 2005

AbstractProduct development is recognized as cross‐functional, knowledge‐intensive work that has become increasingly important in the fast‐paced, globally competitive environment. Researchers and practicing managers contend that design engineers may play an important role in product development efforts. However, their effect on the product development process is not well understood and the extent of their impact on product development performance has not been adequately accessed. This research defines the changing role of design engineers, and it discusses their impact on setting clear project targets and sharing knowledge about customers. The study investigates the impact of these variables on product development productivity. Data collected from 205 manufacturing firms were used to create valid and reliable instruments to assess role change of design engineers, clarity of project targets, shared knowledge about customers and product development productivity. Results from structural equation modeling indicate that as the role of design engineers expands the clarity of project targets increase. This increase impacts the extent of shared knowledge about customers. Increases in the clarity of project targets and shared knowledge about customers appear to enhance product development productivity.
Uncemented short‐length diaphyseal segmental replacement prosthesis fixation—Finite element analysis and long‐term results
Authors: Werner C. M. L. , Jacob H. A. C. , Ramseier L. E. , Favre P. , Exner G. U. 
Published: May 2005

AbstractIntroduction: Extensively porous coated segmental replacement prostheses with intramedullary cementless fixation to bone over the whole length of stem often exhibit resorption of the surrounding bone due to stress‐shielding. This makes them particularly susceptible to aseptic loosening.Study: A finite element analysis of the state of loading of a short‐length fixation in a new prosthetic stem design has shown a definite advantage over long‐length fixation. The stress pattern within the bone surrounding the prosthesis confirmed that shortening of the ongrowth area in length increases the stress values at the resection level significantly. This stem (Endlock) has been used for diaphyseal anchorage in the treatment of tumors in combination with an artificial joint of proven design in order to reduce stress shielding.Results: No Endlock stem fractures or aseptic loosenings were observed at recent follow‐up. The early clinical results comply with the theoretical assumptions.Conclusions: A short‐length fixation system based on intramedullary anchorage of segmental replacement endoprostheses would possibly support physiologic adaptive processes more than fixation over the full length of the stem. © 2005 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
The effect of herbal supplementation on the severity of exercise-induced pulmonary haemorrhage
Authors: Epp TS , McDonough P , Padilla DJ , Cox JH , Poole DC , Erickson HH 
Published: May 2005

AbstractExercise-induced pulmonary haemorrhage (EIPH) is a serious condition that affects the health and possibly the performance of all racehorses. However, only two treatments, furosemide and the Flair™ equine nasal strip, both of which reduce capillary transmural pressure, have been successful in reducing EIPH. Alternatively, transient impairment of platelet function and coagulation during exercise has been considered an additional contributor to EIPH. Consequently, herbal formulations designed to enhance platelet function, and hence coagulation, are hypothesized to reduce EIPH. To investigate the validity of this hypothesis, five Thoroughbred horses completed three maximal incremental exercise tests on a 10% inclined treadmill in a randomized cross-over design experiment. Treatments included twice daily oral administration (for 3 days) of a placebo (PL; cornstarch) and two herbal formulas,Yunnan Paiyao(YP) orSingle Immortal(SI). Blood samples for coagulation profiles, complete blood counts and biochemistry profiles were collected before each exercise test. During each test, pulmonary arterial pressure, oxygen uptake, arterial blood gases, plasma lactate and time-to-fatigue were measured. Severity of EIPH was quantified via bronchoalveolar lavage (BAL) at 30–60 min post-exercise. The herbal formulations were not effective in decreasing EIPH (×106red blood cells ml−1BAL fluid: PL, 27.1±11.6; YP, 33.2±23.4; SI, 35.3±15.4,P>0.05) or in changing any of the other variables measured with the exception of time-to-fatigue, which was slightly but significantly prolonged bySingle Immortalcompared with placebo andYunnan Paiyao(PL, 670±9.6 s; YP, 665±5.5 s; SI, 685±7.9 s,P<0.05). Thus, these results do not support the use of these herbal formulations in the prevention of EIPH.
Oxygen uptake (VO2) kinetics in different species: a brief review
Authors: Poole David C , Kindig Casey A , Behnke Brad J , Jones Andrew M 
Published: May 2005

AbstractWhen a human begins to move or locomote, the energetic demands of its skeletal muscles increase abruptly and the oxygen (O2) transport system responds to deliver increased amounts of O2to the respiring mitochondria. It is intuitively reasonable that the rapidity with which O2transport can be increased to and utilized by (VO2) the contracting muscles would be greater in those species with a higher maximal VO2capacity (i.e., VO2max). This review explores the relationship between VO2maxand VO2dynamics or kinetics at across a range of species selected, in part, for their disparate VO2maxcapacities. In healthy humans there is compelling evidence that the speed of the VO2kinetics at the onset of exercise is limited by an oxidative enzyme inertia within the exercising muscles rather than by VO2delivery to those muscles. This appears true also for the horse and dog but possibly not for a certain species of frog. Whereas there is a significant correlation between VO2maxand the speed of VO2kinetics among different species, it is possible to identify species or individuals within a species that exhibit widely disparate mass-specific VO2maxcapacities but similar VO2kinetics (i.e., superlative human athlete and horse).
Partitioning direct and indirect human‐induced effects on carbon sequestration of managed coniferous forests using model simulations and forest inventories
Authors: Vetter Mona , Wirth Christian , Böttcher Hannes , Churkina Galina , Schulze Ernst‐Detlef , Wutzler Thomas , Weber Georg 
Published: May 2005

AbstractTemperate forest ecosystems have recently been identified as an important net sink in the global carbon budget. The factors responsible for the strength of the sinks and their permanence, however, are less evident. In this paper, we quantify the present carbon sequestration in Thuringian managed coniferous forests. We quantify the effects of indirect human‐induced environmental changes (increasing temperature, increasing atmospheric CO2 concentration and nitrogen fertilization), during the last century using BIOME‐BGC, as well as the legacy effect of the current age‐class distribution (forest inventories and BIOME‐BGC). We focused on coniferous forests because these forests represent a large area of central European forests and detailed forest inventories were available.The model indicates that environmental changes induced an increase in biomass C accumulation for all age classes during the last 20 years (1982–2001). Young and old stands had the highest changes in the biomass C accumulation during this period. During the last century mature stands (older than 80 years) turned from being almost carbon neutral to carbon sinks. In high elevations nitrogen deposition explained most of the increase of net ecosystem production (NEP) of forests. CO2 fertilization was the main factor increasing NEP of forests in the middle and low elevations.According to the model, at present, total biomass C accumulation in coniferous forests of Thuringia was estimated at 1.51 t C ha−1 yr−1 with an averaged annual NEP of 1.42 t C ha−1 yr−1 and total net biome production of 1.03 t C ha−1 yr−1 (accounting for harvest). The annual averaged biomass carbon balance (BCB: biomass accumulation rate‐harvest) was 1.12 t C ha−1 yr−1 (not including soil respiration), and was close to BCB from forest inventories (1.15 t C ha−1 yr−1). Indirect human impact resulted in 33% increase in modeled biomass carbon accumulation in coniferous forests in Thuringia during the last century. From the forest inventory data we estimated the legacy effect of the age‐class distribution to account for 17% of the inventory‐based sink. Isolating the environmental change effects showed that these effects can be large in a long‐term, managed conifer forest.
Structural characteristics and chemical composition of birch (Betula pendula) leaves are modified by increasing CO2 and ozone
Authors: Oksanen Elina , Riikonen Johanna , Kaakinen Seija , Holopainen Toini , Vapaavuori Elina 
Published: May 2005

AbstractImpacts of ozone and CO2 enrichment, alone and in combination, on leaf anatomical and ultrastructural characteristics, nutrient status and cell wall chemistry in two European silver birch (Betula pendula Roth) clones were studied. The young soil‐growing trees were exposed in open‐top chambers over three growing seasons to 2 × ambient CO2 and/or ozone concentrations in central Finland. The trees were measured for changes in altogether 35 variables of leaf structure, nutrients and cell wall chemistry of green leaves, and 20 of the measured variables were affected by CO2 and/or O3. Elevated CO2 increased the size of chloroplasts and starch grains, number of mitochondria, P : N ratio, and contents of cell wall hemicellulose. Elevated CO2 decreased the total leaf thickness, specific leaf area, concentrations of N, K, Cu, S and Fe, and contents of cell wall α‐cellulose, uronic acids, acid‐soluble lignin and acetone‐soluble extractives. Elevated ozone led to thinner leaves, higher palisade to spongy ratio, increased number of peroxisomes and mitochondria, reduced content of Mn, Zn, Cu, hemicellulose and uronic acids, and lower Mn : N and Zn : N ratios. In the combined exposure, interactions were antagonistic. Ultrastructural changes became more evident towards the end of the exposure. Young leaves were tolerant against ozone‐caused oxidative stress, whereas oxidative H2O2 accumulation was found in older leaves. CO2 enrichment improved ozone tolerance not only through increased photosynthesis rates, but also through changes in cell wall chemistry (hemicellulose, in particular). However, nutrient imbalances due to ozone and/or CO2 may predispose the trees to other biotic and abiotic stresses. Down‐regulation and up‐regulation of photosynthesis under elevated CO2 through anatomical changes is discussed.
Analysing temperature response of decomposition of organic matter
Authors: Hyvönen Riitta , Ågren Göran I. , Dalias Panagiotis 
Published: May 2005

AbstractIn order to analyse temperature effects on decomposition of organic matter, we tested the following hypothesis: Can an Arrhenius type of equation with constant parameter values for the temperature response of decomposer growth rate adequately describe decomposition of organic matter or must some additional properties be made functions of temperature? Possible temperature effects were analysed by aggregating data in different ways from an experiment with 14C‐labelled wheat material incubated in the laboratory at different temperatures and with soil materials collected from seven coniferous forest stands in Europe. Our analysis shows that it is possible to let all the temperature dependence reside in the decomposer growth rate. The analysis also supports the use of an Arrhenius type of equation for the temperature response of decomposer growth rate but with the parameters specific for each soil, or at least a distinction between organic and mineral horizons seems necessary.
Net ecosystem CO2 exchange in Mojave Desert shrublands during the eighth year of exposure to elevated CO2
Authors: Jasoni Richard L. , Smith Stanley D. , Arnone John A. 
Published: May 2005

AbstractArid ecosystems, which occupy about 35% of the Earth's terrestrial surface area, are believed to be among the most responsive to elevated [CO2]. Net ecosystem CO2 exchange (NEE) was measured in the eighth year of CO2 enrichment at the Nevada Desert Free‐Air CO2 Enrichment (FACE) Facility between the months of December 2003–December 2004. On most dates mean daily NEE (24 h) (μmol CO2 m−2 s−1) of ecosystems exposed to elevated atmospheric CO2 were similar to those maintained at current ambient CO2 levels. However, on sampling dates following rains, mean daily NEEs of ecosystems exposed to elevated [CO2] averaged 23 to 56% lower than mean daily NEEs of ecosystems maintained at ambient [CO2]. Mean daily NEE varied seasonally across both CO2 treatments, increasing from about 0.1 μmol CO2 m−2 s−1 in December to a maximum of 0.5–0.6 μmol CO2 m−2 s−1 in early spring. Maximum NEE in ecosystems exposed to elevated CO2 occurred 1 month earlier than it did in ecosystems exposed to ambient CO2, with declines in both treatments to lowest seasonal levels by early October (0.09±0.03 μmol CO2 m−2 s−1), but then increasing to near peak levels in late October (0.36±0.08 μmol CO2 m−2 s−1), November (0.28±0.03 μmol CO2 m−2 s−1), and December (0.54±0.06 μmol CO2 m−2 s−1). Seasonal patterns of mean daily NEE primarily resulted from larger seasonal fluctuations in rates of daytime net ecosystem CO2 uptake which were closely tied to plant community phenology and precipitation. Photosynthesis in the autotrophic crust community (lichens, mosses, and free‐living cyanobacteria) following rains were probably responsible for the high NEEs observed in January, February, and late October 2004 when vascular plant photosynthesis was low. Both CO2 treatments were net CO2 sinks in 2004, but exposure to elevated CO2 reduced CO2 sink strength by 30% (positive net ecosystem productivity=127±17 g C m−2 yr−1 ambient CO2 and 90±11 g C m−2 yr−1 elevated CO2, P=0.011). This level of net C uptake rivals or exceeds levels observed in some forested and grassland ecosystems. Thus, the decrease in C sequestration seen in our study under elevated CO2– along with the extensive coverage of arid and semi‐arid ecosystems globally – points to a significant drop in global C sequestration potential in the next several decades because of responses of heretofore overlooked dryland ecosystems.