bluuebunny/crossref_metadata_2025 huggingface dataset:
Activity-Dependent Differential Transmitter Release in Mouse Adrenal Chromaffin Cells
Authors: Fulop Tiberiu , Radabaugh Stephen , Smith Corey
Published: August 2005

Chromaffin cells of the adrenal medulla are a primary neuroendocrine output of the sympathetic nervous system. When stimulated, they secrete a host of transmitter molecules, including catecholamines and neuropeptides, through the fusion of dense core secretory granules with the cell surface. At basal firing rates, set by the sympathetic tone, chromaffin cells selectively release catecholamines at a modest rate. Stress-mediated sympathetic activation leads to elevated catecholamine secretion and also evokes neuropeptide release. Catecholamines and neuropeptides are copackaged in the same granules; thus, it is unclear how this activity-dependent differential transmitter release is achieved. In this report, we use electrophysiological, electrochemical, fluorescence, and immunocytochemical approaches to quantify transmitter release under physiological electrical stimulation at the single cell level. We provide data to show that chromaffin cells selectively release catecholamine under basal firing conditions but release both neuropeptides and catecholamines under conditions that match acute stress. We further show that this differential transmitter release is achieved through a regulated activity-dependent dilation of the granule fusion pore. Thus, chromaffin cells may regulate release of different transmitters through a simple size-exclusion mechanism.
Distinct Fibroblast Growth Factor (FGF)/FGF Receptor Signaling Pairs Initiate Diverse Cellular Responses in the Oligodendrocyte Lineage
Authors: Fortin Dale , Rom Eran , Sun Haijun , Yayon Avner , Bansal Rashmi
Published: August 2005

Fibroblast growth factors (FGFs) have been implicated in numerous cellular processes, including proliferation, migration, differentiation, and survival. Whereas FGF-2, the prototypic ligand in a family of 22 members, activates all four tyrosine kinase FGF receptors (FGFR1-FGFR4), other members demonstrate a higher degree of selectivity. Oligodendrocytes (OLs), the myelin-producing cells of the CNS, are highly influenced by FGF-2 at all stages of their development. However, how other FGFs and their cognate receptors orchestrate the development of OLs is essentially undefined. Using a combination of specific FGF ligands and receptor blocking antibodies, we now show that FGF-8 and FGF-17 target OL progenitors, inhibiting their terminal differentiation via the activation of FGFR3, whereas FGF-9 specifically targets differentiated OLs, triggering increases in process growth via FGFR2 signaling; FGF-18 targets both OL progenitors and OLs via activation of both FGFR2 and FGFR3. These events are highly correlated with changes in FGF receptor expression from FGFR3 to FGFR2 as OL progenitors differentiate into mature OLs. In addition, we demonstrate that, although activation of FGFR1 by FGF-2 leads to proliferation of OL progenitors, it produces deleterious effects on differentiated OLs (i.e., aberrant reentry into cell cycle and down-regulation of myelin proteins with a loss of myelin membrane). These data suggest that ligand availability, coupled with changes in FGF receptor expression, yield a changing repertoire of ligand-receptor signaling complexes that contribute critically to the regulation of both normal OL development and potential OL/myelin pathogenesis.
Migration Depths of Adult Spring and Summer Chinook Salmon in the Lower Columbia and Snake Rivers in Relation to Dissolved Gas Supersaturation
Authors: Johnson Eric L. , Clabough Tami S. , Bennett David H. , Bjornn Theodore C. , Peery Christopher A. , Caudill Christopher C. , Stuehrenberg Lowell C.
Published: August 2005

High spill volume at dams can create supersaturated dissolved gas conditions that may have negative effects on fish. Water spilling over Columbia and Snake River dams during the spring and summer creates plumes with high dissolved gas that extend downstream of dam spillways and throughout reservoirs and creates gas‐supersaturated conditions throughout the water column. During the spring and summer of 2000, 228 adult Chinook salmon Oncorhynchus tshawytscha were tagged at Bonneville Dam with archival radio data storage transmitters (RDSTs) that recorded depth and water temperature as the fish migrated through dams and reservoirs of the lower Columbia and Snake rivers. Swimming depths from 131 of the 228 adult spring and summer Chinook salmon tagged with RDSTs were used to estimate the potential for gas bubble formation given in‐river dissolved gas concentrations and hydrostatic compensation. We found that adult spring and summer Chinook salmon spent a majority of the time at depths that would have provided adequate hydrostatic compensation for in‐river dissolved gas conditions during this study, which were at or slightly below long‐term averages. Adult spring and summer Chinook salmon spent a majority of their time at depths deeper than 2 m, interspersed with periods lasting minutes at depths shallower than 2 m. Statistical associations were weak between the percent and duration of time fish occupied depths near the surface and dissolved gas concentrations, suggesting a lack of behavioral avoidance. Collectively, these data suggest little potential for negative effects of gas supersaturation on adult spring and summer Chinook salmon under average river conditions, despite the fact that fish tissues were probably supersaturated with dissolved gases. However, additional research over a broader range of dissolved gas conditions is needed to confirm that short, but frequent, exposure to conditions conducive to gas bubble formation does not affect survival and reproductive potential.
Stable Isotope Variability in Tissues of Temperate Stream Fishes
Authors: Jardine Timothy D. , Gray Michelle A. , McWilliam Sherisse M. , Cunjak Richard A.
Published: August 2005

Previous measurements of stable isotope ratios in fishes have typically used white muscle, but potential applications exist for the use of other tissues. We tested three tissues (liver, fin, and gonad) in three freshwater species (juvenile Atlantic salmon Salmo salar, slimy sculpin Cottus cognatus, and brook trout Salvelinus fontinalis) to investigate potential ecological applications of stable isotopes in tissues other than muscle. Caudal fin tissue correlated closely with muscle tissue for Atlantic salmon and brook trout for δ13C (r = 0.96 and 0.94, respectively) and δ15N (r = 0.80 and 0.74). Liver δ13C values were tightly linked to muscle values, and differences were due to lipid effects. Associations between liver and muscle δ15N suggested subtle changes in nutritional status. Isotope ratios of gonads differed markedly between male and female slimy sculpin; these differences were probably governed by differences in the allocation of specific nutrients. Knowledge of isotopic fractionation among tissues will aid fish biologists in nonlethal sampling of fishes for stable isotope analysis and in using stable isotopes to assess nutritional status and the allocation of nutrients to reproduction.
Movement and Habitat Use of Yearling and Juvenile Lake Sturgeon in Black Lake, Michigan
Authors: Smith Kregg M. , King Donna K.
Published: August 2005

Information about the distribution, movement, and home ranges of lake sturgeon Acipenser fulvescens was incomplete in the Great Lakes region; therefore, the objective for this study was to determine habitat selection and the extent of movement by two life stages of lake sturgeon in Black Lake, Michigan. Ultrasonic transmitters were surgically implanted into yearling (age‐1) and juvenile (age‐5–13) lake sturgeon. The yearling lake sturgeon implanted with transmitters averaged 36.04 cm total length (TL) and 207.2 g, while the juvenile lake sturgeon tracked during this survey averaged 97.23 cm TL. Previous studies of movements and habitat use by lake sturgeon have noted distinct areas of use by groups of adult lake sturgeon in riverine environments. In contrast to these findings, yearling and juvenile lake sturgeon in the present study used individual areas of activity. Comparisons between our study and studies conducted in lotic environments suggest that core areas of activity for groups of lake sturgeon may be more important for lake sturgeon inhabiting flowing environments. Two distinct mean depths (nearshore and deep offshore habitats) were used by yearlings, while juveniles utilized deep, flat‐bottomed offshore habitat. Yearling lake sturgeon were associated significantly with sand and organic substrate types rather than clay or sand–organic substrate, while juveniles were associated with organic substrate types. Median distances moved between locations were significantly different between yearlings that used nearshore habitat and those that used offshore habitat. Juvenile lake sturgeon larger than 90 cm displayed longer median daily linear movements and occupied larger home ranges than did juveniles smaller than 90 cm. The findings from this study illustrate the different habitats used at various lake sturgeon life history stages in a lake environment.
Zooplankton Size Selection Relative to Gill Raker Spacing in Rainbow Trout
Authors: Budy Phaedra , Haddix Tyler , Schneidervin Roger
Published: August 2005

Rainbow trout Oncorhynchus mykiss are one of the most widely stocked salmonids worldwide, often based on the assumption that they will effectively utilize abundant invertebrate food resources. We evaluated the potential for feeding morphology to affect prey selection by rainbow trout using a combination of laboratory feeding experiments and field observations in Flaming Gorge Reservoir, Utah–Wyoming. For rainbow trout collected from the reservoir, inter–gill raker spacing averaged 1.09 mm and there was low variation among fish overall (SD = 0.28). Ninety‐seven percent of all zooplankton observed in the diets of rainbow trout collected in the reservoir were larger than the interraker spacing, while only 29% of the zooplankton found in the environment were larger than the interraker spacing. Over the size range of rainbow trout evaluated here (200–475 mm), interraker spacing increased moderately with increasing fish length; however, the size of zooplankton found in the diet did not increase with increasing fish length. In laboratory experiments, rainbow trout consumed the largest zooplankton available; the mean size of zooplankton observed in the diets was significantly larger than the mean size of zooplankton available. Electivity indices for both laboratory and field observations indicated strong selection for larger‐sized zooplankton. The size threshold at which electivity switched from selection against smaller‐sized zooplankton to selection for larger‐sized zooplankton closely corresponded to the mean interraker spacing for both groups (∼1–1.2 mm). The combination of results observed here indicates that rainbow trout morphology limits the retention of different‐sized zooplankton prey and reinforces the importance of understanding how effectively rainbow trout can utilize the type and sizes of different prey available in a given system. These considerations may improve our ability to predict the potential for growth and survival of rainbow trout within and among different systems.
Breeding Structure of Steelhead Inferred from Patterns of Genetic Relatedness among Nests
Authors: Kuligowski David R. , Ford Michael J. , Berejikian Barry A.
Published: August 2005

Ten polymorphic microsatellite loci were used to infer kinship among steelhead Oncorhynchus mykiss sampled from nest sites in the Hamma Hamma River, Washington. Fertilized eggs were removed from 8 of 11 redds (i.e., individual nests within redds) surveyed in 1998, tagged with unique identifiers, and reared until adulthood as part of a conservation program. On average, individuals sampled from the same redd were more closely related than individuals sampled from different redds, and a tree generated from the pairwise relatedness estimates shows clear clustering of individuals by redd. Despite this general pattern, there was substantial overlap in the pairwise relatedness estimates within and among most redds. Of the eight redds, seven contained more than four alleles at a minimum of one locus and five contained more than six alleles, indicating that most redds were the result of matings by more than a single pair of parents. In total, the eight redds were created by a minimum of 21 parents, which we inferred to consist of at least 5 females and 16 males based on the location and timing of redd construction. The male‐biased sex ratio is probably due to matings by either male resident trout or precocial steelhead parr with female steelhead. The results of this study indicate that although multiple matings by both sexes are common in this population, the variance in reproductive success is much higher for males than females.
Inheritance Studies Implicate a Genetic Mechanism for Apparent Sex Reversal in Chinook Salmon
Authors: Williamson Kevin S. , May Bernie
Published: August 2005

The apparent increase in altered sexual differentiation in Pacific salmon Oncorhynchus spp. is a growing concern. Previous studies suggest that incongruence between genetic and phenotypic sex in Chinook salmon O. tshawytscha may be a result of altered sexual differentiation through exposure to endocrine‐disrupting chemicals (EDCs). Artificial crosses between genotypically normal Chinook salmon, or between genotypically normal males and apparent sex‐reversed males (XY females), were performed to test the validity of OtY1 and growth hormone pseudogene (GHΨ) genetic markers as indicators of phenotypic sex in fall‐run Chinook salmon. The offspring produced were genotyped with the Y‐chromosome‐specific markers and were dissected to observe gonad morphology. The results of the breeding experiments indicate that approximately half of the phenotypic female offspring of XY females have a male genotype according to both Y‐chromosome markers. These results refute an earlier hypothesis that phenotypic female Chinook salmon with a male genotype (XY females) are the result of altered sexual differentiation caused by EDC exposure. Instead, either the OtY1 and GHΨ markers have recombined between the Y and X chromosomes or an autosome, or a mutation has inactivated the sex‐determining region of the Y chromosome. In none of the 2,384 Chinook salmon evaluated did the genetic markers contradict one another in a single individual. These results present evidence that both OtY1 and the GHΨ genetic markers appear to not be diagnostic for sex in fall‐run Chinook salmon in the Central Valley of California.
Estimation of Stock Composition and Individual Identification of Sockeye Salmon on a Pacific Rim Basis Using Microsatellite and Major Histocompatibility Complex Variation
Authors: Beacham Terry D. , Candy John R. , McIntosh Brenda , MacConnachie Cathy , Tabata Amy , Kaukinen Karia , Deng Langtuo , Miller Kristina M. , Withler Ruth E. , Varnavskaya Natalia
Published: August 2005

The variation at 14 microsatellite loci and one major histocompatibility complex (MHC) locus was surveyed for over 48,000 sockeye salmon Oncorhynchus nerka sampled from 299 localities ranging from the Columbia River to Japan. For the microsatellite loci, the number of alleles observed at a locus was related to the power of the locus in providing accurate estimates of stock composition of single‐population mixtures. In an analysis of single‐population mixtures where the Pacific Rim baseline was used for estimation of stock identification, 80% accuracy for the average population was achieved by employing approximately 80 alleles in the analysis. Increasing the accuracy of estimated stock compositions to 90% for the average population required approximately 400 microsatellite alleles. When all loci were used to estimate stock compositions, estimates were above 80% for all sampling sites or populations, above 90% for the lake of origin, and generally above 95% for the region of origin. Analysis of known‐origin samples indicated that accurate lake or regional estimates of stock composition were obtained. The accuracy of identification of individual fish to the correct lake of origin was above 90%, regardless of whether the lakes were geographically widespread or within a single watershed. The estimated stock compositions of mixed‐fishery samples from the western Bering Sea, from the continental shelf near Kodiak Island in the Gulf of Alaska, from Southeast Alaska, and from Johnstone Strait in southern British Columbia were markedly different among samples. These stock compositions reflected geographical variation in fishery locations and variation in the migration pathways of either juvenile or maturing sockeye salmon. Variation of DNA enabled us to estimate accurately the origin of individual fish and the composition of mixed‐stock samples from any location in the Pacific Rim distribution of sockeye salmon.
Uptake and Transport of Radioactive Nickel and Cadmium into Three Vegetables after Wet Aerial Contamination
Authors: Fismes Joëlle , Echevarria Guillaume , Leclerc‐Cessac Elisabeth , Morel Jean Louis
Published: August 2005

Knowledge of radionuclide or trace element retention and translocation to plants following an aerial contamination event, for example, sprinkling with contaminated water, is necessary for the evaluation of human exposure through consumption of contaminated vegetables. The fate of 63Ni and 109Cd in all plant parts of three different vegetables after wet deposition on leaves or on fruits was studied. Lettuce (Lactuca sativa L.), radish (Raphanus sativus L.), and bean (Phaseolus vulgaris L.) grown under controlled conditions in a growth chamber were contaminated with 63Ni and 109Cd either on leaves, by means of two different contamination methods (a single early contamination and a repetitive one), or on bean husks (third contamination method: a single contamination at a late stage). Spiked and nonspiked organs were harvested at maturity and radionuclide contents were measured. The fraction retained was on average 56% of the initially administered doses of 63Ni and 87% of 109Cd. The leaf‐to‐other organ translocation factor was considerably higher for 63Ni (on average 43% of retained radioactivity) than for 109Cd (8%). Nickel‐63 migrated throughout the whole plant following foliar contamination, and mainly toward young leaves, seeds in formation, and sink organs, whereas 109Cd migrated to a much lesser extent and only to the organs that were closest to the spiked one, and not at all into fruit. After a fruit contamination event, both radionuclides were translocated into the seeds of spiked fruits. Radionuclide retention and translocation were not affected by plant species, but principally by the type of organ contaminated.
Manipulation of Dietary Protein and Nonstarch Polysaccharide to Control Swine Manure Emissions
Authors: Clark O. Grant , Moehn Soenke , Edeogu Ike , Price Jason , Leonard Jeremy
Published: August 2005

Odor and greenhouse gas (GHG) emissions from stored pig (Sus scrofa) manure were monitored for response to changes in the crude protein level (168 or 139 g kg−1, as‐fed basis) and nonstarch polysaccharide (NSP) content [i.e., control, or modified with beet pulp (Beta vulgaris L.), cornstarch, or xylanase] of diets fed to pigs in a production setting. Each diet was fed to one of eight pens of pigs according to a 2 × 4, full‐factorial design, replicated over three time blocks with different groups of animals and random assignment of diets. Manure from each treatment was characterized and stored in a separate, ventilated, 200‐L vessel. Repeated measurements of odor, carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) emissions from the vessels were taken every two weeks for eight weeks. Manure from high‐protein diets had higher sulfur concentration and pH (P ≤ 0.05). High‐NSP (beet pulp) diets resulted in lower manure nitrogen and ammonia concentrations and pH (P ≤ 0.05). Odor level and hedonic tone of exhaust air from the storage vessel headspaces were unaffected by the dietary treatments. Mean CO2 and CH4 emissions (1400 and 42 g d−1 m−3 manure, respectively) increased with lower dietary protein (P ≤ 0.05). The addition of xylanase to high‐protein diets caused a decrease in manure CO2 emissions, but an increase when added to low‐protein diets (P ≤ 0.05). Nitrous oxide emissions were negligible. Contrary to other studies, these results do not support the use of dietary protein reduction to reduce emissions from stored swine manure.
Soil Characteristics and Phosphorus Level Effect on Phosphorus Loss in Runoff
Authors: Davis Randall L. , Zhang Hailin , Schroder Jackie Lee , Wang Jim J. , Payton Mark E. , Zazulak Anne
Published: August 2005

The loss of phosphorus (P) in runoff from agricultural soils may accelerate eutrophication in lakes and streams as well as degrade surface water quality. Limited soil specific data exist on the relationship between runoff P and soil P. This study investigated the relationship between runoff dissolved reactive phosphorus (DRP) and soil P for three Oklahoma benchmark soils: Richfield (fine, smectitic, mesic Aridic Argiustoll), Dennis (fine, mixed, active, thermic Aquic Argiudoll), and Kirkland (fine, mixed, superactive, thermic Udertic Paleustoll) series. These soils were selected to represent the most important agricultural soils in Oklahoma across three major land resource areas. Surface soil (0–15 cm) was collected from three designated locations, treated with diammonium phosphate (18–46–0) to establish a wide range of water‐soluble phosphorus (WSP) (3.15–230 mg kg−1) and Mehlich‐3 phosphorus (M3P) (27.8–925 mg kg−1). Amended soils were allowed to reach a steady state 210 d before simulated rainfall (75 mm h−1). Runoff was collected for 30 min from bare soil boxes (1.0 × 0.42 m and 5% slope) and analyzed for DRP and total P. Soil samples collected immediately before rainfall simulation were analyzed for the following: M3P, WSP, ammonium oxalate P saturation index (PSIox), water‐soluble phosphorus saturation index (PSIWSP), and phosphorus saturation index calculated from M3P and phosphorus sorption maxima (Psat). The DRP in runoff was highly related (p < 0.001) to M3P for individual soil series (r2 > 0.92). Highly significant relationships (p < 0.001) were found between runoff DRP and soil WSP for the individual soil series (r2 > 0.88). Highly significant relationships (p < 0.001) existed between DRP and different P saturation indexes. Significant differences (p < 0.05) among the slopes of the regressions for the DRP–M3P, DRP–WSP, DRP–PSIox, DRP–PSIWSP, and DRP–Psat relationships indicate that the relationships are soil specific and phosphorus management decisions should consider soil characteristics.
Polycyclic Aromatic Hydrocarbons (PAHs) in Soils of the Moscow Region— Concentrations, Temporal Trends, and Small‐Scale Distribution
Authors: Wilcke Wolfgang , Krauss Martin , Safronov Grigorij , Fokin Alexej D. , Kaupenjohann Martin
Published: August 2005

The knowledge of the environmental fate of polycyclic aromatic hydrocarbons (PAHs) is restricted to few climatic regions of the world almost excluding the Taiga. Our objectives were to (i) separate anthropogenic from background contributions to PAH concentrations and (ii) determine temporal trends in PAH concentrations during the last century including the change in distribution of PAHs in interior and exterior portions of aggregates in soils of the Moscow region. Along a southeast‐bound transect from Moscow (windward in winter) and at a background location northeast of Moscow (leeward in winter), seven topsoil samples were collected in 1910–1954 and 35 in 1998–2003. We fractionated the soils in interior and exterior portions of aggregates > 10 mm and remaining soil without aggregates. The sum of 21 PAHs (Σ21PAHs) concentrations in recent bulk soil ranged from 59 to 1350 ng g−1 The concentrations of all PAHs were lower outside than in Moscow. The range of the concentrations of the Σ21PAHs in archived soil samples (159–1280 ng g−1) was similar as in recent soils. In most recent and archived samples, naphthalene and phenanthrene, were most abundant. The concentrations of low‐molecular‐weight PAHs decreased during the last century at most sites; those of high‐molecular‐weight compounds increased. The Σ21PAHs concentrations were accumulated in the exterior of aggregates (109%) and depleted in the interior (95%) relative to the concentration in bulk soil (defined as 100%), which was similar to that in the soil without aggregates (99%). The differences between aggregate interior and exterior did not change during the last century. The dominance of naphthalene and phenanthrene is typical of remote regions. The urban influence on PAH concentrations in the last century was small.
Nitrogen Oxide and Methane Emissions under Varying Tillage and Fertilizer Management
Authors: Venterea Rodney T. , Burger Martin , Spokas Kurt A.
Published: August 2005

Comprehensive assessment of the total greenhouse gas (GHG) budget of reduced tillage agricultural systems must consider emissions of nitrous oxide (N2O) and methane (CH4), each of which have higher global warming potentials than carbon dioxide (CO2). Tillage intensity may also impact nitric oxide (NO) emissions, which can have various environmental and agronomic impacts. In 2003 and 2004, we used chambers to measure N2O, CH4, and NO fluxes from plots that had been managed under differing tillage intensity since 1991. The effect of tillage on non‐CO2 GHG emissions varied, in both magnitude and direction, depending on fertilizer practices. Emissions of N2O following broadcast urea (BU) application were higher under no till (NT) and conservation tillage (CsT) compared to conventional tillage (CT). In contrast, following anhydrous ammonia (AA) injection, N2O emissions were higher under CT and CsT compared to NT. Emissions following surface urea ammonium nitrate (UAN) application did not vary with tillage. Total growing season non‐CO2 GHG emissions were equivalent to CO2 emissions of 0.15 to 1.9 Mg CO2 ha−1 yr−1 or 0.04 to 0.53 Mg soil‐C ha−1 yr−1 Emissions of N2O from AA‐amended plots were two to four times greater than UAN‐ and BU‐amended plots. Total NO + N2O losses in the UAN treatment were approximately 50% lower than AA and BU. This study demonstrates that N2O emissions can represent a substantial component of the total GHG budget of reduced tillage systems, and that interactions between fertilizer and tillage practices can be important in controlling non‐CO2 GHG emissions.
Quantifying the Impact of Regular Cutting on Vegetative Buffer Efficacy for Nitrogen‐15 Sequestration
Authors: Bedard‐Haughn A. , Tate K. W. , van Kessel C.
Published: August 2005

This study used the stable 15N isotope to quantitatively examine the effects of cutting on vegetative buffer uptake of NO3−–N based on the theory that regular cutting would increase N demand and sequestration by encouraging new plant growth. During the summer of 2002, 10 buffer plots were established within a flood‐irrigated pasture. In 2003, 15N‐labeled KNO3 was applied to the pasture area at a rate of 5 kg N ha−1 and 99.7 atom % 15N. One‐half of the buffer plots were trimmed monthly. In the buffers, the cutting effect was not significant in the first few weeks following 15N application, with both the cut and uncut buffers sequestering 15N. Over the irrigation season, however, cut buffers sequestered 2.3 times the 15N of uncut buffers, corresponding to an increase in aboveground biomass following cutting. Cutting and removing vegetation allowed the standing biomass to take advantage of soil 15N as it was released by microbial mineralization. In contrast, the uncut buffers showed very little change in 15N sequestration or biomass, suggesting senescence and a corresponding decrease in N demand. Overall, cutting significantly improved 15N attenuation from both surface and subsurface water. However, the effect was temporally related, and only became significant 21 to 42 d after 15N application. The dominant influence on runoff water quality from irrigated pasture remains irrigation rate, as reducing the rate by 75% relative to the typical rate resulted in a 50% decrease in total runoff losses and a sevenfold decrease in 15N concentration.
Molecular Composition of Leaves and Stems of Genetically Modified Bt and Near‐Isogenic Non‐Bt Maize—Characterization of Lignin Patterns
Authors: Poerschmann Juergen , Gathmann Achim , Augustin Juergen , Langer Uwe , Górecki Tadeusz
Published: August 2005

Transformation of crops, including maize (Zea mays L.), with the cry1Ab gene from Bacillus thuringiensis to combat lepidopteran pests results in pleiotropic effects regarding lignin biosynthesis. Lignin patterns in stems and leaves of two genetically modified Bt‐maize varieties (Novelis T and Valmont T) were studied along with their non‐Bt near‐isolines (Nobilis and Prelude, respectively). Molecular‐level based thermochemolysis using tetramethylammonium hydroxide (TMAH) in combination with gas chromatography–mass spectrometry (GC–MS) was used to quantitate the total lignin contents and to identify monomeric lignin subunits including p‐hydroxyphenyl (P), guaiacyl (G), and syringyl (S) moieties. The results were supplemented and confirmed by cupric oxide oxidation. The stems of the transgenic lines had higher concentrations of total lignin than the respective isogenic lines: Valmont T/Prelude by 18% and Novelis T/Nobilis by 28%. In contrast, differences in the total lignin concentration of leaves between the transgenic and the respective near‐isogenic lines were marginal. There were significant modifications in the ratio of p‐hydroxyphenyl/guaiacyl/syringyl molecular marker units of stem lignin between transgenic and isogenic lines. The guaiacyl units (in particular the G18 marker) accounted chiefly for the higher total lignin contents in the transgenic lines. The leaf lignin patterns did not show significant differences in molecular markers between isogenic and transgenic lines. TMAH‐induced thermochemolysis—conducted in both the on‐line and off‐line modes—provided detailed information on the molecular composition of lignin, thus proving superior to the established “wet chemistry” methods of lignin determination.
The effect of nanofibers on liquid–liquid coalescence filter performance
Authors: Shin C. , Chase G. G. , Reneker D. H.
Published: August 2005

A number of factors influence the efficiency and the economics of the separation of dispersed liquid drops in an immiscible liquid–liquid mixture. One important factor that controls the performance of a filter medium in the separation is the fiber size. Electrospun polymer nanofibers have diameters in the nanometer range and are arbitrarily long. The experimental results in this work show that adding nanofibers to conventional micron‐sized fibrous filter media improves the separation efficiency of the filter media but also increases the pressure drop. An optimum in the performance occurs (significant increase in efficiency with minimal increase in pressure drop) with the addition of about 1.6% by mass of 250 nm diameter nylon 6 nanofibers to 5 micron diameter glass fibers in the filters. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Infants with Bochdalek diaphragmatic hernia: Sibling precurrence and monozygotic twin discordance in a hospital‐based malformation surveillance program
Authors: Pober Barbara R. , Lin Angela , Russell Meaghan , Ackerman Kate G. , Chakravorty Sharmila , Strauss Bernarda , Westgate Marie Noel , Wilson Jay , Donahoe Patricia K. , Holmes Lewis B.
Published: August 2005

Congenital diaphragmatic hernia (CDH) is a common and often devastating birth defect. In order to learn more about possible genetic causes, we reviewed and classified 203 cases of the Bochdalek hernia type identified through the Brigham and Women's Hospital (BWH) Active Malformation Surveillance Program over a 28‐year period. Phenotypically, 55% of the cases had isolated CDH, and 45% had complex CDH defined as CDH in association with additional major malformations or as part of a syndrome. When classified according to likely etiology, 17% had a Recognized Genetic etiology for their CDH, while the remaining 83% had No Apparent Genetic etiology. Detailed analysis using this largest cohort of consecutively collected cases of CDH showed low precurrence among siblings. Additionally, there was no concordance for CDH among five monozygotic twin pairs. These findings, in conjunction with previous reports of de novo dominant mutations in patients with CDH, suggest that new mutations may be an important mechanism responsible for CDH. The twin data also raise the possibility that epigenetic abnormalities contribute to the development of CDH. © 2005 Wiley‐Liss, Inc.
Effect of gelatin on the swelling behavior of organic hybrid gels based on N‐isopropylacrylamide and gelatin
Authors: Lee Wen‐Fu , Lee Sung‐Chuan
Published: August 2005

Organic hybrid gels based on poly(N‐isopropylacrylamide) and a natural polymer, gelatin, were prepared through two‐step crosslinking with genipin or glutaraldehyde. The effects of the gelatin content on the swelling behaviors and physical properties of these hybrid gels were investigated. The results indicated that the swelling ratio decreased with an increase in the content of gelatin in these hybrid gels. The swelling ratio for the gel crosslinked by genipin was significantly smaller than that for the gel crosslinked by glutaraldehyde. The results also showed that the gel crosslinked with genipin had a higher crosslinking density and a higher gel strength. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1092–1099, 2005
Synthesis, properties, and self‐assembly of poly(benzyl ether)‐b‐polystyrene dendritic–linear polymers
Authors: Jiang Guohua , Wang Li , Chen Tao , Wang Jianfeng , Chen Chang , Yu Haojie
Published: August 2005

Poly(benzyl ether)‐b‐polystyrene dendritic–linear polymers were successfully synthesized using a dendritic chloric poly(benzyl ether) (G1‐Cl, G2‐Cl, and G3‐Cl) as the macroinitiator through the atom transfer radical polymerization process. The structure and properties of the resultant polymers were characterizated by gel permeation chromatography, 1H‐NMR, Fourier transform IR, thermogravimetric analysis, and differential scanning calorimetry. It was found that the temperature, reaction time, molar ratio of the macroinitiator to styrene, and the generation number of the macroinitiator have significant effects on the molecular weights, conversion, and polydispersities of the resulting polymers. These dendritic–linear block polymers had very good solubility in common organic solvents at room temperature. The terminal group (dendritic segments) of the polymers can affect their thermal stability. These dendritic–linear polymers after self‐assembling in selective solvents (chloroform/acetone) formed core–shell micelles. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1106–1112, 2005
Gas permeation studies of natural rubber and carboxylated styrene–butadiene rubber latex membranes
Authors: Stephen Ranimol , Thomas Sabu , Joseph Kuruvilla
Published: August 2005

Predicting the permeability of natural rubber (NR), carboxylated styrene–butadiene rubber (XSBR), and NR/XSBR latex membranes has been investigated with special reference to the effects of the blend ratio, the pressure, and the nature of the permeants with oxygen and nitrogen gases. These blend membranes are a new class of materials that combine the excellent mechanical properties of NR and the weather and solvent resistance of XSBR. NR shows higher permeability than XSBR latex films. This is associated with the high extent of the flexibility of the NR network due to its very low cohesive forces of interactions. The experimentally determined permeability values have been theoretically correlated with the Maxwell, Bruggeman, and Bottcher models. The oxygen‐to‐nitrogen selectivity decreases with an increase in the XSBR content in the blend. Attempts have been made to correlate the transport characteristics with the morphology of the blend. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1125–1134, 2005
Effects of the aluminum filler content on moisture diffusion into epoxy adhesives in distilled water and sea water
Authors: Kahraman Ramazan
Published: August 2005

Epoxies are the most common of high‐performance structural adhesives, especially in automotive and aircraft manufacturing. In a variety of industrial applications, epoxy adhesives are required to have enhanced thermal conductivity. The normal method of changing this property is to add to the epoxy a filler of higher conductivity than the continuous phase. Although the improvement in the thermal properties of adhesives by the addition of metal fillers is obvious, their influence on water sorption characteristics of adhesives is not clear. It was the objective of this study to shed light on these aspects, which are lacking in the literature. The emphasis was placed on determining the moisture sorption behavior of aluminum‐powder‐filled epoxy adhesives under complete immersion in distilled water and sea water. Moisture diffusion tests show that the addition of aluminum filler into epoxy decreases the total amount of water intake at saturation in both fluids. However, there appears to be no significant effect of the aluminum filler content on the moisture diffusivity in epoxy adhesive specimens in either distilled water or seawater. It has also been determined that the adhesives adsorb a larger amount of water upon exposure to distilled water than when exposed to seawater, whereas the moisture diffusion rate in the adhesive immersed in seawater is higher than that in distilled water. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1165–1171, 2005
Thermal degradation kinetics of polyethylene and silane‐crosslinked polyethylene
Authors: Zong Ruowen , Wang Zhengzhou , Liu Naian , Hu Yuan , Liao Guanxuan
Published: August 2005

The thermal degradation of linear low‐density polyethylene (LLDPE) and linear low‐density silane‐crosslinked polyethylene (SXLPE) was studied. Kinetic evaluations were performed by model‐free kinetic analysis and multivariate nonlinear regression. Apparent kinetic parameters for the overall degradation were determined. The results show that the thermal stability of SXLPE was higher than that of LLDPE. Their decomposition reaction model was a single‐step process of an nth‐order reaction. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1172–1179, 2005
Ultraviolet‐curing behavior of an epoxy acrylate resin system
Authors: Hong Bong Taek , Shin Kwon Shik , Kim Dae Su
Published: August 2005

Ultraviolet (UV)‐curing behavior of an epoxy acrylate resin system comprising an epoxy acrylate oligomer, a reactive diluent, and a photoinitiator was investigated by Fourier transform infrared (FTIR) spectroscopy. The conversion changes of the resin system containing 20 phr of 1,6‐hexanediol diacrylate as a reactive diluent and 2‐hydroxy‐2‐methyl‐1‐phenyl‐propan‐1‐one as a photoinitiator were measured under different UV‐curing conditions. The fractional conversion was calculated from the area of the absorption peak for the vinyl group vibration occurring at 810 cm−1. The effects of photoinitiator concentration, total UV dosage, one‐step or stepwise UV irradiation, UV intensity, atmosphere, and temperature on the curing behavior of the resin system were investigated. The conversion of the resin system increased rapidly at the initial stage of the UV‐curing process but increased very slowly after that. The final conversion of the resin system was mainly affected by total UV dosage. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1180–1185, 2005
Terpolymer films having semipolar structure: Preparation, wettability, and mechanical properties
Authors: Hiwatashi Tomoaki , Hayama Kazuhide , Sawada Yoshiaki , Itoh Takahito
Published: August 2005

A terpolymer, obtained by the free‐radical terpolymerization of 2‐(N,N‐dimethylamino)ethyl methacrylate (DMMA), methyl methacrylate(MMA), and isobutyl methacrylate (IBMA), was allowed to react with hydrogen peroxide, chloroacetic acid, and diethyl sulfate to form the corresponding modified terpolymers: (1) N,N‐dimethyl‐N‐(2‐methacryloyloxyethyl)amine N‐oxide, MMA and IBMA (DMANO series); (2) N‐(carboxymethyl)‐N,N‐dimethyl‐ N‐(2‐methacryloyloxyethyl)ethyl ammonium, MMA and IBMA (CDME series); and (3) N‐(ethyl)‐N,N‐dimethyl‐N‐(2‐methacryloyloxyethyl)ethyl ammonium ethylsulfonate, MMA and IBMA (EDMEES series), respectively. The terpolymer compositions were determined using 13C NMR spectrometry. Surface free energies of the terpolymers were estimated by measuring the contact angles of water and methylene iodide on the three series films (DMANO, CDME, and EDMEES), and the effect of the N‐oxide group on wettability was discussed. It was found that the upper surface of the films for the DMANO and CDME series are more hydrophobic than that for the EDMEES series. Notably, elongation to break for the DMANO series was relatively larger than that for the CDME series because of the water bound to the N‐oxide functional group. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1235–1243, 2005
Neurogenesis and neuronal communication on micropatterned neurochips
Authors: Bani‐Yaghoub Mahmud , Tremblay Roger , Voicu Raluca , Mealing Geoff , Monette Robert , Py Christophe , Faid Karim , Sikorska Marianna
Published: August 2005

Neural networks are formed by accurate connectivity of neurons and glial cells in the brain. These networks employ a three‐dimensional bio‐surface that both assigns precise coordinates to cells during development and facilitates their connectivity and functionality throughout life. Using specific topographic and chemical features, we have taken steps towards the development of poly(dimethylsiloxane; PDMS) neurochips that can be used to generate and study synthetic neural networks. These neurochips have micropatterned structures that permit adequate cell positioning and support cell survival. Within days of plating, cells differentiate into neurons displaying excitability and communication, as evidenced by intracellular calcium oscillations and action potentials. The structural and functional capacities of such simple neural networks open up new opportunities to study synaptic communication and plasticity. © 2005 Wiley Periodicals, Inc.
A family‐based mental health program of recovery from state terror in Kosova
Authors: Griffith James L. , Agani Ferid , Weine Stevan , Ukshini Shqipe , Pulleyblank‐Coffey Ellen , Ulaj Jusuf , Rolland John , Blyta Afrim , Kallaba Melita
Published: August 2005

Family processes of communication, mutual support, and sustenance of cultural values can play vital roles in recovery from psychological and material damage in societies afflicted by terror. This is particularly the case when a campaign of terror has specifically targeted family life and its traditions, when the culture is one whose identity has been centered in its families, and when public mental health resources have been scarce. At the end of the 1999 war in Kosova, the Kosovar Family Professional Educational Collaborative (KFPEC) was initiated to counter mental health sequelae of war in Kosova. This initiative focused upon the recovery and strengthening of Kosovar families, rather than the psychiatric treatment of individuals for post‐traumatic symptoms. Findings and outcomes from this project may usefully inform the design of other international public mental health initiatives. Copyright © 2005 John Wiley & Sons, Ltd.
Social psychology, terrorism, and identity: a preliminary re‐examination of theory, culture, self, and society
Authors: Arena Michael P. , Arrigo Bruce A.
Published: August 2005

This article relies upon structural symbolic interactionism and five of its organizing concepts (i.e. symbols, the definition of the situation, roles, socialization and role‐taking, and the self) to put forth a novel conceptual framework for understanding the terrorist identity. In order to demonstrate the practical utility of the framework, applications to various terrorist groups around the globe are incorporated into the analysis. Overall, both the theoretical and application work help reorient the academic and practitioner behavioral science communities to the importance of culture, self, and society when investigating one's membership in and identity through militant extremist organizations. Given the unique approach taken by this article, several provisional implications are delineated. In particular, future research on terrorism, strategies linked to counter‐terrorism, legal and public policy reform, and the relevance of utilizing a sociologically animated social psychology in the assessment of other forms of criminal behavior are all very tentatively explored. Copyright © 2005 John Wiley & Sons, Ltd.
Long‐term outcome after radiotherapy alone for lymphocyte‐predominant Hodgkin lymphoma
Authors: Wirth Andrew , Yuen Kally , Barton Michael , Roos Daniel , Gogna Kumar , Pratt Gary , MacLeod Craig , Bydder Sean , Morgan Graeme , Christie David
Published: August 2005

BACKGROUND

The curative potential of radiotherapy (RT) alone as initial treatment for patients with Stage I–II lymphocyte‐predominant Hodgkin lymphoma (LPHL) has not been defined well.

METHODS

Two hundred two patients who were treated between 1969 and 1995 were evaluated in a retrospective, multicenter study.

RESULTS

Patient characteristics were as follows: The median age was 31 years, 75% of patients were male, 80% of patients had Ann Arbor Stage I disease, 1% of patients had bulky disease, 3% of patients had B symptoms, 1% of patients had extranodal involvement, and 80% of patients had supradiaphragmatic disease. The RT fields were a full mantle field in 52% of patients, less than a full mantle field in 24% of patients, an inverted‐Y field in 17% of patients, less than an inverted‐Y field in 3% of patients, and total lymph node irradiation in 3% of patients. The median dose was 36 Gray. The median follow‐up was 15 years. The overall survival (OS) rate at 15 years was 83%, and freedom from progression (FFP) was observed in 82% of patients, including 84% of patients with Stage I disease and 73% of patients with Stage II disease. No recurrent LPHL and only 1 patient with non‐Hodgkin lymphoma (NHL) were reported after 15 years. Adverse prognostic factors that were identified on multifactor analysis were as follows: for OS, age 45 years or older (P < 0.0005), the presence of B symptoms (P = 0.002), increasing number of sites (P = 0.015); for FFP, increasing number of sites (P = 0.002). No significant difference was found in FFP in a comparison of patients who received elective mediastinal RT with patients who did not receive mediastinal RT (P = 0.11). Causes of death at 15 years were LPHL in 3% of patients, NHL in 2% of patients, in‐field malignancy in 2% of patients, in‐field cardiac/respiratory in 4% of patients, and other in 6% of patients.

CONCLUSIONS

The current data suggested that RT potentially may be curative for patients with Stage I–II LPHL and raise the possibility that limited‐field RT may be used without loss of treatment efficacy. Involved‐field RT warrants further investigation for patients with early‐stage LPHL. Cancer 2005. © 2005 American Cancer Society.
Synthesis and Structures of Bi(1,1‐stannole)s
Authors: Saito Masaichi , Haga Ryuta , Yoshioka Michikazu
Published: August 2005

The synthesis and structures of bi(1,1‐stannole)s are described. Treatment of 1‐bromo‐4‐(dibromophenylstannyl)‐1,3‐butadiene with tert‐butyllithium gives the bi(1,1‐stannole) having a phenyl group on each tin atom, whereas treatment of 1‐bromo‐4‐(tribromostannyl)‐1,3‐butadiene with phenyl‐ or bulky alkyllithiums gives the bi(1,1‐stannole) having a phenyl or an alkyl group on each tin atom. The X‐ray analysis of the tert‐butyl‐substituted bi(1,1‐stannole) is also described. All bi(1,1‐stannole)s display two shoulder absorption bands due to π–π* and σ–π* transitions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)