bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evolutionary Conservation of Ceratitis capitata transformer Gene Function
Authors: Pane Attilio , De Simone Annamaria , Saccone Giuseppe , Polito Catello 
Published: July 2005

Abstract
Transformer functions as a binary switch gene in the sex determination and sexual differentiation of Drosophila melanogaster and Ceratitis capitata, two insect species that separated nearly 100 million years ago. The TRA protein is required for female differentiation of XX individuals, while XY individuals express smaller, presumably nonfunctional TRA peptides and consequently develop into adult males. In both species, tra confers female sexual identity through a well-conserved double-sex gene. However, unlike Drosophila tra, which is regulated by the upstream Sex-lethal gene, Ceratitis tra itself is likely to control a feedback loop that ensures the maintenance of the female sexual state. The putative CcTRA protein shares a very low degree of sequence identity with the TRA proteins from Drosophila species. However, in this study we show that a female-specific Ceratitis Cctra cDNA encoding the putative full-length CcTRA protein is able to support the female somatic and germline sexual differentiation of D. melanogaster XX; tra mutant adults. Although highly divergent, CcTRA can functionally substitute for DmTRA and induce the female-specific expression of both Dmdsx and Dmfru genes. These data demonstrate the unusual plasticity of the TRA protein that retains a conserved function despite the high evolutionary rate. We suggest that transformer plays an important role in providing a molecular basis for the variety of sex-determining systems seen among insects.
Gene Expression During Drosophila Wing Morphogenesis and Differentiation
Authors: Ren Nan , Zhu Chunming , Lee Haeryun , Adler Paul N 
Published: July 2005

Abstract
The simple cellular composition and array of distally pointing hairs has made the Drosophila wing a favored system for studying planar polarity and the coordination of cellular and tissue level morphogenesis. We carried out a gene expression screen to identify candidate genes that functioned in wing and wing hair morphogenesis. Pupal wing RNA was isolated from tissue prior to, during, and after hair growth and used to probe Affymetrix Drosophila gene chips. We identified 435 genes whose expression changed at least fivefold during this period and 1335 whose expression changed at least twofold. As a functional validation we chose 10 genes where genetic reagents existed but where there was little or no evidence for a wing phenotype. New phenotypes were found for 9 of these genes, providing functional validation for the collection of identified genes. Among the phenotypes seen were a delay in hair initiation, defects in hair maturation, defects in cuticle formation and pigmentation, and abnormal wing hair polarity. The collection of identified genes should be a valuable data set for future studies on hair and bristle morphogenesis, cuticle synthesis, and planar polarity.
A Genetic Screen for Dominant Modifiers of a Small-Wing Phenotype in Drosophila melanogaster Identifies Proteins Involved in Splicing and Translation
Authors: Coelho Carmen M A , Kolevski Benjamin , Walker Cherryl D , Lavagi Irene , Shaw Thomas , Ebert Anselm , Leevers Sally J , Marygold Steven J 
Published: July 2005

Abstract
Studies in the fly, Drosophila melanogaster, have revealed that several signaling pathways are important for the regulation of growth. Among these, the insulin receptor/phosphoinositide 3-kinase (PI3K) pathway is remarkable in that it affects growth and final size without disturbing pattern formation. We have used a small-wing phenotype, generated by misexpression of kinase-dead PI3K, to screen for novel mutations that specifically disrupt organ growth in vivo. We identified several complementation groups that dominantly enhance this small-wing phenotype. Meiotic recombination in conjunction with visible markers and single-nucleotide polymorphisms (SNPs) was used to map five enhancers to single genes. Two of these, nucampholin and prp8, encode pre-mRNA splicing factors. The three other enhancers encode factors required for mRNA translation: pixie encodes the Drosophila ortholog of yeast RLI1, and RpL5 and RpL38 encode proteins of the large ribosomal subunit. Interestingly, mutations in several other ribosomal protein-encoding genes also enhance the small-wing phenotype used in the original screen. Our work has therefore identified mutations in five previously uncharacterized Drosophila genes and provides in vivo evidence that normal organ growth requires optimal regulation of both pre-mRNA splicing and mRNA translation.
Cost of Interacting With Sexual Partners in a Facultative Sexual Microbe
Authors: Xu Jianping 
Published: July 2005

Abstract
The widespread occurrence of sexual organisms despite the high costs of sex has long intrigued biologists. The best-known costs are the twofold cost of producing males and the cost associated with producing traits to attract mates and to interact with mating partners, such as exaggerated sexual behaviors and morphological modifications. These costs have been inferred from studies of plants and animals but are thought to be absent in facultative sexual microbes. Here, using the facultative sexual fungus Cryptococcus neoformans, I provide experimental evidence showing that: (i) interactions with active sexual partners can be costly for vegetative fitness in a facultative sexual microbe; (ii) this cost is positively correlated to mating ability; (iii) this cost is composed of at least two distinct components, the cost of producing mating signals that exert effects on mating partners and that associated with responding to active mating partners; and (iv) extended asexual reproduction can reduce both components of the cost. This cost must have been compensated for by the production of zygotes and sexual spores to allow the initial evolution and spread of sexual reproduction in eukaryotes.
Transcriptional Compensation for Gene Loss Plays a Minor Role in Maintaining Genetic Robustness in Saccharomyces cerevisiae
Authors: Wong Sharyl L , Roth Frederick P 
Published: July 2005

Abstract
If a gene is mutated and its function lost, are compensatory genes upregulated? We investigated whether genes are transcriptionally upregulated when their synthetic sick or lethal (SSL) partners are lost. We identified several new examples; however, remarkably few SSL pairs exhibited this phenomenon, suggesting that transcriptional compensation by SSL partners is a rare mechanism for maintaining genetic robustness.
Exploitation of Nile Tilapia in a Closed-System Public Fishing Reservoir in Northern Arkansas
Authors: Henry Sam D. , Barkley Sam W. , Johnson Ronald L. 
Published: July 2005

Abstract
Nile tilapia Oreochromis niloticus have been stocked as a forage species annually since 2001 in Lake Hogue, a 101-ha, closed-system public fishing reservoir in northeastern Arkansas. A mail-in reward tag study was implemented in 2003 to determine total estimated harvest, contribution of Nile tilapia to the lake's fishery, and impact of angler harvest on Nile tilapia reproduction. Estimates of harvest were corrected for tag loss (1.1%), tag-induced mortality (1.0%), and nonreporting of tags by anglers (53% reporting rate). Angler-hours were compared between anglers targeting Nile tilapia and those targeting other species. Anglers harvested an estimated 83% of the stocked Nile tilapia (56% of stocked fish were captured by traditional panfishing techniques; 27% were captured by use of dip nets during the winter die-off in late November). Anglers targeting primarily Nile tilapia fished significantly longer (5.7 h/angler) than individuals who incidentally caught Nile tilapia while fishing for other species (4.5 h/angler). Analysis of the economic impact of stocking Nile tilapia demonstrated a benefit-cost ratio of 0.38. Harvest of Nile tilapia did not apparently interfere with the management goal of using the fish as a forage species for game fishes. Tag return data strongly suggested that at midday during the hot summer months, when fishing pressure had traditionally been low, anglers targeted Nile tilapia in favor of the traditional target species (e.g., bluegill Lepomis macrochirus and redear sunfish L. microlophus).
Establishing a Linkage between Phosphorus Forms in Dairy Diets, Feces, and Manures
Authors: Toor Gurpal S. , Cade‐Menun Barbara J. , Sims J. Thomas 
Published: July 2005

ABSTRACTEffective manure management to efficiently utilize organic wastes without causing environmental degradation requires a clear understanding of the transformation of P forms from diet to manure. Thus, the objective of this study was to establish quantitative relationships between P forms in diets, feces, and manures collected from U.S. Northeastern and Mid‐Atlantic commercial dairy farms. Total P in diets ranged from 3.6 to 5.3 g kg−1 dry matter, while the feces had higher P than diets (5.7–9.5 g kg−1) and manures had lower P (2.5–8.9 g kg−1) than feces. The farms with total dietary P of 4.8 to 5.3 g P kg−1 had twofold higher concentrations of phytic acid (1647–2300 mg P kg−1) than farms with 3.6 to 4.0 g dietary P kg−1 (844–1100 mg P kg−1). Much of the phytic acid in diets was converted to inorganic orthophosphate in the rumen as indicated by a reduction in phytic acid percentage from diets (32%) to feces (18%). The proportion of orthophosphate diesters (phospholipids, deoxyribonucleic acid [DNA]) was twice as high in feces (6.2–10%) as diets (2.4–5.3%) suggesting the excretion of microbial residues in feces. Phosphonates (aminoethyl phosphonates and phosphonolipids) were not seen in diets but were detected in feces and persisted in manures, which suggests a microbial origin. These organic compounds (phytic acid, phospholipids, DNA) were decomposed on storage of feces in slurry pits, increasing orthophosphate in manures by 9 to 12% of total P. These results suggest that reducing dietary P and typically storing feces in dairy farms will result in manure with similar chemical forms (primarily orthophosphate: 63–77%) that will be land applied. Thus, both the reduction of dietary P and storage of manure on farm are important for controlling solubility and bioavailability of P forms in soils and waters.
Bioluminescent Bacteria as Indicators of Chemical Contamination of Coastal Waters
Authors: Frischer M. E. , Danforth J. M. , Foy T. F. , Juraske R. 
Published: July 2005

ABSTRACTThe ratio of bioluminescent to total bacteria (bioluminescent ratio, BLR) as an indicator of a variety of types of anthropogenic contamination of estuarine ecosystems was evaluated through a series of laboratory and field studies. Laboratory studies indicated that the BLR of natural bacterioplankton communities was proportionally reduced in the presence of a number of contaminants including diesel fuel and saltmarsh sediments co‐contaminated with mercury and polychlorinated biphenyls (PCBs). Bioluminescent ratio inhibition was observed after short‐term exposure to a contaminant suggesting a physiological rather than a population response of native microbial communities. Simulated eutrophication did not suppress the BLR. Field observations of the BLR were conducted weekly for a 2‐yr period in the Skidaway River estuary, Georgia, USA. These observations revealed considerable seasonal variability associated with the BLR. Bioluminescent ratios were highest during the summer (25 ± 15%), lower in the fall (6 ± 5%) and spring (3 ± 2%), and near zero during the winter. Although the BLR was not significantly correlated to salinity at a single site (Skidaway River estuary), the BLR was significantly correlated with salinity when sites within the same estuary system were compared (r2 = 0.93). Variation in BLR was not correlated to standard bacteriological indicators of water quality including total and fecal coliform bacteria. Comparison of the BLR from impacted and pristine estuarine sites during the fall suggested that anthropogenically impacted sites exhibited lower BLR than predicted from salinity versus BLR relationships developed in pristine systems. These observations suggest that the BLR could be used as a simple and reliable initial indicator of chemical contamination of estuarine systems resulting from human activity.
Reductive Dechlorination of Tetrachloroethene in a Sand Reactor Using a Potentiostat
Authors: Shimomura Tatsuo , Sanford Robert A. 
Published: July 2005

ABSTRACTIn this study, an electrochemical system was investigated to enhance abiotic dechlorination of chlorinated solvents in contaminated soil in situ. A potentiostatic electrolysis sand reactor was developed and tested to evaluate tetrachloroethene (PCE) dechlorination in saturated sand. When operated with recirculating nutrient‐supplemented water the reactor sustained a low oxidation reduction potential (ORP) at the cathode (<−400 mV standard hydrogen electrode [SHE]), a pH less than 9.4, and electric current >5 mA at room temperature with the cathodic potential controlled at −950 mV SHE. Tetrachloroethene in the electrolysis reactor had a half‐life of 6.8 d compared with the control bioreactor without electrolysis, which had a PCE half‐life of 16.4 d. Ethane and ethene were the main dechlorination products in the test reactor, while trichloroethene (TCE) accumulated in the nutrient‐amended control reactor without electrolysis. An electrolysis reactor operated with water not amended with nutrients showed a PCE half‐life of 7.6 d, suggesting that most of dechlorination activity in the reactor was abiotic. Since complete dechlorination can be achieved under moderate pH and temperature, this type of electrolysis technology is attractive as a remedial method for subsurface chloroethene contamination.
Sorption, Mobility, and Transformation of Estrogenic Hormones in Natural Soil
Authors: Casey Francis X. M. , Šimůnek Jiří , Lee Jaehoon , Larsen Gerald L. , Hakk Heldur 
Published: July 2005

ABSTRACTPotent estrogenic hormones are consistently detected in the environment at low concentration, yet these chemicals are strongly sorbed to soil and are labile. The objective of this research was to improve the understanding of the processes of sorption, mobility, and transformation for estrogens in natural soils, and their interaction. Equilibrium and kinetic batch sorption experiments, and a long‐term column study were used to study the fate and transport of 17β‐estradiol and its primary metabolite, estrone, in natural soil. Kinetic and equilibrium batch experiments were done using radiolabeled 17β‐estradiol and estrone. At the concentrations used, it appeared that equilibrium sorption for both estrogens was achieved between 5 and 24 h, and that the equilibrium sorption isotherms were linear. The logKocvalues for 17β‐estradiol (2.94) and estrone (2.99) were consistent with previously reported values. Additionally, it was found that there was rate‐limited sorption for both 17β‐estradiol (0.178 h−1) and estrone (0.210 h−1). An approximately 42 h long, steady‐flow, saturated column experiment was used to study the transport of radiolabeled 17β‐estradiol, which was applied in a 5.00 mg L−1solution pulse for 44 pore volumes. 17β‐estradiol and estrone were the predominant compounds detected in the effluent. The effluent breakthrough curves were asymmetric and the transport modeling indicated that sorption was rate‐limited. Sorption rates and distributions of the estrogens were in agreement between column and batch experiments. This research can provide a better link between the laboratory results and observations in the natural environment.
Accelerated Weathering of Biosolid‐Amended Copper Mine Tailings
Authors: Pond Andrew P. , White Scott A. , Milczarek Michael , Thompson Thomas L. 
Published: July 2005

ABSTRACTApplication of municipal biosolids to mine tailings can enhance revegetation success, but may cause adverse environmental impacts, such as increased leaching of NO−3and metals to ground water. Kinetic weathering cells were used to simulate geochemical weathering to determine the effects of biosolid amendment on (i) pH of leachate and tailings, (ii) leaching of NO−3and SO42−, (iii) leaching and bioavailability (DTPA‐extractable) of selected metals, and (iv) changes in tailing mineralogy. Four Cu mine tailings from southern Arizona differing in initial pH (3.3–7.3) and degree of weathering were packed into triplicate weathering cells and were unamended and amended with two rates (equivalent to 134 and 200 Mg dry matter ha−1) of biosolids. Biosolid application to acid (pH 3.3) tailings resulted in pH values as high as 6.3 and leachate pH as high as 5.7, and biosolids applied to circumneutral tailings resulted in no change in tailing or leachate pH. Concentrations of NO−3–N of up to 23 mg L−1occurred in leachates from circumneutral tailings. The low pH of the acidic tailing apparently inhibited nitrification, resulting in leachate NO−3–N of <5 mg L−1Less SO42−–S was leached in biosolid‐amended versus unamended acid tailings (final rate of 0.04 compared with 0.11 g SO42−–S wk−1). Copper concentrations in leachates from acidic tailings were reduced from 53 to 27 mg L−1with biosolid amendment. Copper and As concentrations increased slightly in leachates from biosolid‐amended circumneutral tailings. Small increases in DTPA‐extractable Cu, Ni, and Zn occurred in all tailings with increased biosolid rate. Overall, there was little evidence of potential for adverse environmental impacts resulting from biosolid application to these Cu mine tailings.
Nitrate Reduction in the Presence of Wüstite
Authors: Rakshit Sudipta , Matocha Christopher J. , Haszler Gerald R. 
Published: July 2005

ABSTRACTRecent strategies to reduce elevated nitrate NO3− concentrations employ metallic Fe0 as a reductant. Secondary products of Fe0 corrosion include magnetite (Fe3O4), green rust [Fe6(OH)12SO4], and wüstite [FeO(s)]. To our knowledge, no studies have been reported on the reactivity of NO3− with FeO(s). This project was initiated to evaluate the reactivity of FeO(s) with NO3− under abiotic conditions. Stirred batch reactions were performed in an anaerobic chamber over a range of pH values (5.45, 6.45, and 7.45), initial FeO(s) concentrations (1, 5, and 10 g L−1), initial NO3− concentrations (1, 10, and 15 mM), and temperatures (3, 21, 31, and 41°C) for kinetic and thermodynamic determinations. Suspensions were periodically removed and filtered to measure dissolved nitrogen and iron species. Solid phases were characterized using X‐ray diffraction (XRD) and scanning electron microscopy (SEM). Nitrate reduction by FeO was rapid and characterized by nearly stoichiometric conversion of NO3− to NH4+ Transient NO2− formation also occurred. The XRD and SEM results indicated the formation of Fe3O4 as a reaction product of the heterogeneous redox reaction. Kinetics of NO3− reduction suggested a rate equation of the type: where k = 3.46 × 10−3 ± 0.38 × 10−3 M−1 s−1, at 25°C. Arrhenius and Eyring plots indicate that the reaction is surface chemical–controlled and proceeds by an associative mechanism involving a step where both NO3− and FeO(s) bind together in an intermediate complex.
Impact of Soil Amendments on Reducing Phosphorus Losses from Runoff in Sod
Authors: Torbert H. A. , King K. W. , Harmel R. D. 
Published: July 2005

ABSTRACTResearch was initiated to study the interaction between soil amendments (lime, gypsum, and ferrous sulfate) and dissolved molybdate reactive phosphorus [RP(<0.45)] losses from manure applications from concentrated runoff flow through a sod surface. Four run‐over boxes (2.2‐m2 surface area) were prepared for each treatment with a bermudagrass [Cynodon dactylon (L.) Pers.] sod surface (using sod blocks) and composted dairy manure was surface‐applied at rates of 0, 4.5, 9, or 13.5 Mg ha−1 The three soil amendments were then applied to the boxes. Two 30‐min runoff events were conducted and runoff water was collected at 10‐min intervals and analyzed for RP(<0.45) Results indicated that the addition of ferrous sulfate was very effective at reducing the level of RP(<0.45) in runoff water, reducing RP(<0.45) from 1.3 mg L−1 for the highest compost rate with no amendment to 0.2 mg L−1 for the ferrous sulfate in the first 10 min of runoff. Lime and gypsum showed a small impact on reducing RP(<0.45), with a reduction in the first 10 min to 0.9 and 0.8 mg L−1, respectively. The ferrous sulfate reduced the RP(<0.45) in the tank at the end of the first runoff event by 66.3% compared with no amendment. In the second runoff event, the ferrous sulfate was very effective at reducing RP(<0.45) in runoff, with no significant differences in RP(<0.45) with application of 13.5 Mg ha−1 compost compared with no manure application. The results indicate that the addition of ferrous sulfate may greatly reduce RP(<0.45) losses in runoff and has considerable potential to be used on pasture, turfgrass, and filter strips to reduce the initial RP(<0.45) losses from manure application to the environment.
White Spruce Response to Co‐Composted Hydrocarbon‐Contaminated Drilling Waste
Authors: Choi Woo‐Jung , Chang Scott X. , Hao Xiying 
Published: July 2005

ABSTRACTThere are growing interests to use co‐composted drilling wastes contaminated with hydrocarbons as growth media for planting in land reclamation. However, such use of the compost may have potential problems such as inherent toxicity of residual hydrocarbon and microbial N immobilization due to high compost C to N ratios. We investigated the growth, biomass production, N uptake, and foliar δ13C of white spruce (Picea glauca[Moench] Voss) seedlings in a pot experiment using 1‐, 2‐, 3‐, and 4‐yr‐old composts (with different hydrocarbon concentrations and C to N ratios) and a local noncontaminated soil with (200 kg N ha−1) or without N fertilization. Growth and N content of seedlings (particularly N content in roots) were lower when grown in the compost media as compared with those grown in the soil. Within the compost treatments seedling growth was affected by compost age, but the magnitude of growth reduction was not linearly proportional to hydrocarbon concentrations. Plant N uptake increased with compost age, which corresponds with an increase in indigenous mineral N concentration. Effects of N fertilization on N uptake were curtailed by the presence of indigenous mineral N (e.g., in the 4‐yr‐old compost) and by fertilization‐induced stimulation of microbial activities (e.g., in the 1‐yr‐old compost). The differences in foliar δ13C values between seedlings grown in compost and soil (P< 0.05) suggest that limitations on water uptake caused by the residual hydrocarbon might have been the predominant factor limiting seedling growth in the compost media. This study suggests that water stress caused by residual hydrocarbons may be a critical factor for the successful use of co‐composted drilling wastes as a growth medium.
Hydrogen‐Bonding Motifs in Fullerene Chemistry
Authors: Sánchez Luis , Martín Nazario , Guldi Dirk M. 
Published: July 2005

AbstractThe combination of fullerenes and hydrogen‐bonding motifs is a new interdisciplinary field in which weak intermolecular forces allow modulation of one‐, two‐, and three‐dimensional fullerene‐based architectures and control of their function. This Minireview aims to extend the scope of fullerene chemistry to a truly supramolecular level from which unprecedented architectures may evolve. It is shown that electronic communication in C60‐based hydrogen‐bonded donor–acceptor ensembles is at least as strong as that found in covalently connected systems and that hydrogen‐bonding fullerene chemistry is a versatile concept for the construction of functional ensembles.