bluuebunny/crossref_metadata_2025 huggingface dataset:
Morphological attributes of oriental spruce [ Picea orientalis (L.) Link.] seedlings grown in peat-based media amended with natural zeolite
Authors: Ayan S. , Tilki F.
Published: September 2007

This study was designed to investigate the influence of growth media consisting of different components on the morphological attributes of oriental spruce seedlings. Eighteen different combinations of Barma peat (BP), tea residue compost (CTR), fine pumice (FP), coarse pumice (CP), perlite (P) and zeolite (Z) were prepared as growth media.The growth medium components did not significantly affect the shoot height (SH), root collar diameter (RCD), shoot:root ratio or dry root percentage (DRP) of 2-year-old seedlings. However, the root dry weight (RDW) and shoot dry weight (SDW) showed significant differences between the different growth media. The maximum SDW (3.244 g) was determined for a mixture of BP (0.5) + CTR (0.2) + CP (0.2) + Z (0.1), while a mixture of BP (0.6) + P (0.2) + Z (0.2) resulted in minimum SDW (1.593 g). In addition, the maximum RDW (1.824 g) was determined for the BP (0.5) + CTR (0.2) + CP (0.2) + Z (0.1) medium, while the BP (0.6) + CP (0.2) + Z (0.2) medium resulted in the lowest RDW (1.013 g). The addition of zeolite to the growth media increased the SDW and RDW of oriental spruce seedlings, so natural zeolite could be used as a substrate to replace pumice and perlite in nurseries in Turkey. Since Turkey has 45.8 billion tonnes of zeolite, its use in nurseries could reduce the costs significantly.
Rapd variation of late-maturing sorghum [ Sorghum bicolor (L.) Moench] landraces from Ethiopia
Authors: Mamo S. , Ayana A. , Tesso T.
Published: September 2007

A study on the extent and pattern of genetic variability in late-maturing sorghum [Sorghum bicolor(L.) Moench] landraces collected from the Wello and Hararge areas of Ethiopia was conducted using random amplified polymorphic DNA (RAPD) markers for 70 individuals representing 14 populations. Four oligonucleotide primers generated a total of 55 polymorphic bands with 13–19 bands per primer and a mean of 16 bands across the 70 individuals. The value of the Shannon diversity index among the populations (0.26) and between the two regions (0.24) was low to moderate, despite the high degree of polymorphic bands per primer. The mean genetic distance (0.25) between the populations was found to be low. The low genetic variation may be due to the reduced population size of late-maturing sorghum landraces in the two regions of Ethiopia because of farmers’ decisions in the process of planting, managing, harvesting and processing their crops. Partitioning of the genetic variation into variation between and within the population revealed that 92.9% and 7.10% of the variation was found to be between and within the populations, respectively. Cluster analysis of genetic distance estimates further confirmed a low level of differentiation in late-maturing sorghum populations both between and within the regions. The implications of the results for genetic conservation purposes are discussed.
Productivity and nitrogen use efficiency parameters in cotton cultivars with varying N levels and soil types under rainfed conditions
Authors: Venugopalan M. , Hebbar K. , Tiwary P. , Chatterji S. , Ramamurthy V. , Challa O. , Sonune B.
Published: September 2007

A field experiment was conducted under rainfed conditions, on a shallow soil (Inceptisol) underlain with weathered basalt and on a deep soil (Vertisol) to evaluate three cotton cultivars [AKH 4 (
Gossypium arboreum
), LRK 516 (
G. hirsutum
) and NHH 44 (intra-
hirsutum
hybrid)] under four levels of N (0, 40, 80 and 120 kg ha
−1
) and to analyse the variations in productivity using the nitrogen use efficiency (NUE) parameter. The yield of AKH4 and NHH 44 was 101 and 89% higher than that of LRK 516. The yield and the response to N were higher on the Inceptisol. The enhanced yield and NUE of AKH 4 and NHH 44 were attributed to the improved efficiency of N uptake utilization. NUE declined from 21.6 at 40 kg ha
−1
to 7.7 at 120 kg N ha
−1
. The N uptake efficiency and N utilization efficiency were independent of each other, but complemented each other in improving NUE. The implications of variations in NUE, N uptake efficiency and N utilization efficiency and their components, N biomass production efficiency and HI, in cotton breeding and agronomy are also discussed.
Protective effect of two synthetic compounds against chlorsulfuron injury in maize ( Zea mays L.)
Authors: Stoilkova G. , Yonova P.
Published: September 2007

Two new synthetic compounds — urea (B-3) and thiourea (B-6) derivatives of 4-methylpiperazinyl — were investigated as possible antidotes for chlorsulfuron in maize. It was established that the thiourea derivative was a more effective herbicide protector than the urea derivative. The shoot length of maize plants treated with 10−5M chlorsulfuron was inhibited 60% compared to the untreated plants, whereas pretreatment with 5×10−4M B-6 reduced this inhibition to 23%. Moreover, the decrease of 53% in shoot fresh weight caused by herbicide applied alone was countered almost completely by B-6 with only an 11% loss in fresh weight observed. The results of this investigation show that the urea derivative (B-3) appeared to be ineffective in antidoting the injurious effect of chlorsulfuron. Decreases in root length and fresh weight were also offset by B-6. The more favourable protective activity of the thioureido group in B-6 could be due to the formation of an isomer with isothiourea structure, having a sulphydryl group. Treatments with herbicide and B-3 / B-6 alone or in combination had no significant effect on the parameters of the antioxidative defence system tested.
Co-inoculation of nitrogen-fixing and phosphate-solubilizing bacteria to promote growth, yield and nutrient uptake in chickpea
Authors: Wani P. , Khan M. , Zaidi A.
Published: September 2007

A total of 32 bacterial isolates includingMesorhizobium(N=10),Azotobacter(N=12) and phosphate-solubilizing bacteria (N=10) were isolated and tested for siderophore, HCN, ammonia, indole acetic acid production and phosphate solubilizationin vitro. The bacterial cultures were positive for siderophore, HCN and ammonia. Among the isolates,M. ciceriRC3 andA. chrococcumA4 displayed 35 and 14 μg ml−1of IAA, respectively, whereasBacillusproduced 19 (BacillusPSB1) and 17 μg ml−1(BacillusPSB10) of IAA in Luria Bertani broth. The diameter of the P solubilization zone varied between 4 (BacillusPSB1) and 5 mm (BacillusPSB10) and a considerable amount of tricalcium phosphate (7 and 8 μg ml−1byBacillusPSB1 andBacillusPSB10, respectively) was released in liquid medium, with a concomitant drop in pH. The effects of N2-fixing and PS bacteria on the growth, chlorophyll content, seed yield, grain protein and N uptake of chickpea plants in field trials varied considerably between the treatments. Nodule number and biomass were significantly greater at 90 days after sowing (DAS), decreasing by 145 DAS. Seed yield increased by 250% due to inoculation withM. ciceriRC3 +A. chroococcumA4 +BacillusPSB10, relative to the control treatment. Grain protein content ranged from 180 (BacillusPSB1) to 309 ng g−1(M. ciceriRC3 +A. chroococcumA4 +BacillusPSB10) in inoculated chickpea. The N contents in roots and shoots differed considerably among the treatments.
Performance and gene effects for root characters and micronutrient uptake in wheat inoculated with arbuscular mycorrhizal fungi and Azotobacter chroococcum
Authors: Singh R. , Behl R. , Jain P. , Narula N. , Singh K.
Published: September 2007

The present investigation was conducted to investigate the impact of bio-inoculants on the magnitude and direction of gene effects and mean performance for root length density, root biomass per plant, AMF colonization in roots and micronutrient uptake (Cu, Fe, Mn, Zn) in wheat under low input field conditions. The material for study comprised three wheat cultivars, WH 147 (low mineral input), WH 533 (drought-tolerant), Raj 3077 (high mineral input) and six generations (P1, P2, F1, F2, BC1and BC2) of three crosses, namely WH 147 × WH 533, WH 533 × Raj 3077 and WH 147 × Raj 3077. The experiment was conducted in a randomized block design with three replications having three treatments, i.e. (i) control; (ii) inoculation with arbuscular mycorrhizal fungi (AMF,Glomus fasciculatum); (iii) dual inoculation with AMF andAzotobacter chroococcum(Azc). The fertilizer doses in all three treatments were 80 kg N + 40 kg P + 18 kg ZnSO4ha−1. Root length density, root biomass per plant, AMF colonization in roots and Zn and Mn content were found to be maximum after dual inoculation with AMF+Azcin all three crosses. Joint scaling tests revealed that additive-dominance gene effects were mainly operative in governing the expression of root biomass, Cu and Zn content in all three crosses for all three treatments (i.e. control, AMF and AMF +Azc). Pedigree selection in crosses WH 147 × WH 533 and WH 147 × Raj 3077 could be effective for breeding pure lines of wheat for sustainable agriculture (low input genotypes responsive to biofertilizers such as AMF andAzotobacter).
Weighted estimates for maximal functions associated with Fourier multipliers
Authors: Sato Shuichi
Published: September 2007

We prove some weighted estimates for maximal functions associated with certain Fourier multipliers of Bochner-Riesz type.
On n -to-one continuous images of β ℕ
Authors: Dow Alan , Mill Jan
Published: September 2007

Eric van Douwen [5] produced a maximal crowded extremally disconnected regular space and showed that its Čech-Stone compactification is an at most two-to-one image of
β
ℕ. We construct for any
n
≧ 3 an example of a compact crowded space
Xn
that is an image of
β
ℕ under a map all of whose fibers have either size
n
or
n
− 1. We also show that under CH this is best possible.
The Effects of Harvesting and Hauling on the Blood Physiology and Fillet Quality of Market-Size Channel Catfish
Authors: Minchew C Douglas , Beecham Rachel V , Pearson Philip R , Green Bartholomew W , Kim Jin M , Bailey Susan B
Published: September 2007

Commercially produced, food-size channel catfish Ictalurus punctatus that were harvested using routine procedures had significant elevations in plasma cortisol, glucose, and lactate compared with preharvest fish captured from open ponds. Blood samples were taken from 10 fish in each of two treatments (liquid oxygen diffuser- and paddlewheel-aerated holding socks) and four sampling periods (before harvest, after socking, before loading, and before unloading) during each of 10 harvest events. Water column temperatures averaged approximately 27°C during the study. Ten fillet samples were taken from fish held overnight in paddlewheel- and liquid oxygen-aerated holding socks during some harvest events. Mean plasma cortisol levels averaged 3.02 ng/mL before harvest, 84.38 ng/mL immediately after socking, 135.22 ng/mL after 18 h in the sock (i.e., before loading onto the truck), and 128.54 ng/mL after 2–3 h on the truck (i.e., before unloading). Mean plasma glucose levels averaged 34.7 mg/dL before harvest, 95.41 mg/dL after socking, 134.53 mg/dL before loading, and 134.86 mg/dL before unloading. Mean plasma lactate levels averaged 2.43 mmol/L before harvest, 13.24 mmol/L after socking, 11.53 mmol/L before loading, and 7.88 mmol/L before unloading. These results should not be considered maximal until additional studies are conducted with average water temperatures at their highest. There were significant changes within treatment over 7 d of refrigerated storage for fillet pH, color, and drip loss; however, there were no consistent trends between treatments. Results indicate that routine capture and hauling procedures are stressful to commercially produced, food-size channel catfish under the examined conditions and that using liquid oxygen for aerating fish in holding socks does not significantly improve fillet quality or reduce stress levels.
Reproduction and Culture of Suckermouth Minnow
Authors: Bestgen Kevin R , Compton Robert I
Published: September 2007

Introduction of captively reared suckermouth minnow Phenacobius mirabilis into Colorado streams where they are rare or extirpated may be a viable technique to enhance the status of this state-endangered species, but information on reproductive ecology and culture techniques is lacking. We successfully spawned suckermouth minnow in the laboratory by using hormone injections, observed reproductive behavior, and reared larvae to juvenile size in aquaria. Suckermouth minnow spawned over interstitial spaces in gravel and cobble substrate in water temperatures of 17, 19, and 23°C after injections of chorionic gonadotropin (males) and carp pituitary (females). Groups of several fish were involved in spawning, which occurred nearly continuously for several hours after the fish were placed in aquaria; typically, only one or a few eggs were released in any single spawning bout. Viable, adhesive eggs were found on gravel and cobble substrate but not on sand or other attachment surfaces in aquaria. Only suckermouth minnow that were in peak reproductive condition successfully spawned after hormone injections. Voluntary spawning also occurred in the absence of hormone injections. We observed potential cannibalism of suckermouth minnow eggs immediately after spawning, suggesting that isolation of embryos or adults after spawning may be necessary for successful culture. Suckermouth minnow were stripped of gametes, and embryos were successfully reared to hatching at temperatures of 17, 19, and 23°C; rearing was most successful at 17°C and 23°C. The development and growth of larvae (4.2–4.8 mm total length at hatching) was faster at 23°C (mean = 0.57 mm/d) than at 17°C and 19°C (0.35 mm/d). The slow initial growth of larvae may be due to food that was of inappropriate size or low quality. Raising suckermouth minnow in captivity may be a useful conservation tool to establish populations in suitable habitat.
Use of Turkey Meal as a Replacement for Menhaden Fish Meal in Practical Diets for Sunshine Bass Grown in Cages
Authors: Thompson Kenneth R , Metts Linda S , Muzinic Laura A , Dasgupta Siddhartha , Webster Carl D , Brady Yolanda J
Published: September 2007

A 391-d feeding trial was conducted with caged juvenile (mean weight = 36.2 g, SD = 8.04 g) sunshine bass (female white bass Morone chrysops × male striped bass M. saxatilis) to evaluate growth, feed conversion, protein efficiency ratio, body composition, and fillet composition resulting from diets with decreasing levels of fish meal (FM; 30, 20, 10, and 0%) and increasing levels of turkey meal (TM; 0.0, 9.7, 17.5, and 26.4%). We stocked 100 randomly selected fish into each of 12 floating cages (3.5 m3). Twice daily, fish were fed all they could consume in 30 min. Four practical diets were formulated to contain 40% protein and to be isoenergetic. After 391 d, significant (P ≤ 0.05) differences were found in growth; fish fed the control diet (30% FM, 0% TM) had higher individual final weight, percent weight gain, and specific growth rate than fish fed 10.0% FM and 17.5% TM. However, differences for those variables were not apparent between the control group and fish fed the 20% FM and 9.7% TM diet or the 0% FM and 26.4% TM diet. Diet composition did not significantly alter amount of diet fed, feed conversion ratio, protein efficiency ratio, percent survival, fillet yield, or hepatosomatic index among treatments. Results indicate that sunshine bass grown in cages for 391 d can be fed a diet containing 0% FM and 26.4% TM without adverse effects on growth, feed conversion ratio, and body composition; more diverse diet formulations for sunshine bass and reduced usage of menhaden fish meal are therefore possible.
Energy Density of Patagonian Aquatic Organisms and Empirical Predictions Based on Water Content
Authors: Ciancio Javier E. , Pascual Miguel A. , Beauchamp David A.
Published: September 2007

We measured the energy density for key species in the freshwater and marine ecosystems of Patagonia, providing the first database of such information for poorly known fauna, including fish, cephalopods, crustaceans, gastropods, annelids, and insects. We then considered an empirical model linking energy density (which is costly to estimate) to water content (which is easy to estimate) and compared the fit of the model with data from different taxonomic groups. Finally, we evaluated the predictive power of models with different levels of taxonomic aggregation to estimate energy density from water content. Fish (7,148‐3,443 J/g of wet weight) had the highest energy density, followed by crustaceans (5,906‐2,507 J/g), insects (5,794‐1,334 J/g), mollusks (5,014‐1,661 J/g), and annelids (4,542‐1,954 J/g). The use of water content as a predictor of energy density provided greatly improved predictions as compared with use of the mean energy density value. As expected, the predictive power improved when more specific levels of taxonomic aggregation were employed. Nevertheless, we were able to identify levels of aggregation that provided high levels of predictive power. We regard the data generated as primary products for future research on energy fluxes in Patagonian aquatic ecosystems.
Estimating Overwinter Survival of Juvenile Coho Salmon in a Northern California Stream: Accounting for Effects of Passive Integrated Transponder Tagging Mortality and Size‐Dependent Survival
Authors: Brakensiek Kyle E. , Hankin David G.
Published: September 2007

We used multiple resightings (live recoveries) of passive integrated transponder (PIT) tagged fish to estimate overwinter (October‐March) survival rates of juvenile coho salmon Oncorhynchus kisutch in a near‐pristine northern California headwater stream. Cormack‐Jolly‐Seber models were used to estimate period‐specific survival rates and recapture probabilities from three tag groups released during October and November 1999 and March 2000. Parameter estimates from the best‐supported models provided strong evidence of initial tagging mortality and also suggested that subsequent survival rates were affected by fish size at tagging. We found statistical evidence for initial PIT tagging mortality, suggested by the lower estimated period‐specific survival rates for tagged fish in their first period at large compared with estimated survival rates for tagged fish that had survived through a previous period. Estimated overwinter survival rates (November‐March) for fish tagged in October that were uncontaminated by initial PIT tagging mortality ranged from about 21% for 55‐mm fish (fork length at tagging) to about 84% for 106‐mm fish (overall average = 45.5%). Lower apparent survival rates for smaller juveniles may reflect (1) size‐dependent movement out of the study reach, (2) chronic size‐dependent mortality related to PIT tagging, or (3) size‐dependent winter mortality unrelated to PIT tagging. We believe that development of successful recovery strategies for coho salmon stocks will require similar stock‐specific (ideal) or region‐specific (minimally adequate) estimates of survival rates through preadult life stages.
Spatial, Temporal, and Ontogenetic Patterns of Predation on Rockfishes by Lingcod
Authors: Beaudreau Anne H. , Essington Timothy E.
Published: September 2007

Predators often play a key role in structuring their prey populations in aquatic systems. We described patterns of predation on rockfishes Sebastes spp. by lingcod Ophiodon elongatus, a top predator in nearshore rocky reef communities along the West Coast of North America, to improve our understanding of the variability, magnitude, and constraints of lingcod feeding on rockfishes. From spring 2004 through fall 2005 we collected diet data from 560 lingcod in the San Juan Archipelago, Washington. Rockfishes were a common component of adult lingcod diets, making up 6.8% of the total diet by number, 11.0% by mass, and 10.5% by frequency of occurrence. Rockfishes were consumed by lingcod in all of the time periods and locations sampled during this study, but rockfish mass and frequency of occurrence in lingcod stomachs varied temporally and spatially. The total mass of rockfish consumed by lingcod during fall 2005 was estimated to be approximately three times as high in marine reserves as in nearby nonreserve areas, providing preliminary evidence for differences in community structure between protected areas and those open to harvest of bottom fish. Prey size spectra demonstrated that lingcod are capable of ingesting rockfish larger than 25 cm in standard length (SL), but the diet data suggest that they more commonly consume rockfish measuring 4‐24 cm SL, including the adult stages of the small‐bodied Puget Sound rockfish S. emphaeus and possibly the juvenile stages of larger rockfish such as copper rockfish S. caurinus and quillback rockfish S. maliger. These findings will inform development of future modeling and empirical studies that will ultimately provide improved insight into the relative top‐down effects of lingcod predation and fishing on rockfish populations.
Bone Morphogenetic Protein Signaling and Olig1/2 Interact to Regulate the Differentiation and Maturation of Adult Oligodendrocyte Precursor Cells
Authors: Cheng Xiaoxin , Wang Yaping , He Qian , Qiu Mengsheng , Whittemore Scott R. , Cao Qilin
Published: September 2007

Promotion of remyelination is an important therapeutic strategy for the treatment of the demyelinating neurological disorders. Adult oligodendrocyte precursor cells (OPCs), which normally reside quiescently in the adult central nervous system (CNS), become activated and proliferative after demyelinating lesions. However, the extent of endogenous remyelination is limited because of the failure of adult OPCs to mature into myelinating oligodendrocytes (OLs) in the demyelinated CNS. Understanding the molecular mechanisms that regulate the differentiation of adult OPCs could lead to new therapeutic strategies to treat these disorders. In this study, we established a stable culture of adult spinal cord OPCs and developed a reliable in vitro protocol to induce their sequential differentiation. Adult OPCs expressed bone morphogenetic protein (BMP) type Ia, Ib, and II receptor subunits, which are required for BMP signal transduction. BMP2 and 4 promoted dose-dependent astrocyte differentiation of adult OPCs with concurrent suppression of OL differentiation. Treatment of OPCs with BMP2 and 4 increased ID4 expression and decreased the expression of olig1 and olig2. Overexpression of olig1 or olig2 blocked the astrocyte differentiation of adult OPCs induced by BMP2 and 4. Furthermore, overexpression of both olig1 and olig2, but not olig1 or olig2 alone, rescued OL differentiation from inhibition by BMP2 and 4. Our results demonstrated that downregulation of olig1 and olig2 is an important mechanism by which BMP2 and 4 inhibit OL differentiation of adult OPCs. These data suggest that blocking BMP signaling combined with olig1/2 overexpression could be a useful therapeutic strategy to enhance endogenous remyelination and facilitate functional recovery in CNS demyelinated disorders.

Disclosure of potential conflicts of interest is found at the end of this article.
Fas Transduces Dual Apoptotic and Trophic Signals in Hematopoietic Progenitors
Authors: Pearl-Yafe Michal , Stein Jerry , Yolcu Esma S. , Farkas Daniel L. , Shirwan Haval , Yaniv Isaac , Askenasy Nadir
Published: September 2007

Stem cells and progenitors are often required to realize their differentiation potential in hostile microenvironments. The Fas/Fas ligand (FasL) interaction is a major effector pathway of apoptosis, which negatively regulates the expansion of differentiated hematopoietic cells. The involvement of this molecular interaction in the function of hematopoietic stem and progenitor cells is not well understood. In the murine syngeneic transplant setting, both Fas and FasL are acutely upregulated in bone marrow-homed donor cells; however, the Fas+ cells are largely insensitive to FasL-induced apoptosis. In heterogeneous populations of lineage-negative (lin−) bone marrow cells and progenitors isolated by counterflow centrifugal elutriation, trimerization of the Fas receptor enhanced the clonogenic activity. Inhibition of caspases 3 and 8 did not affect the trophic signals mediated by Fas, yet it efficiently blocked the apoptotic pathways. Fas-mediated tropism appears to be of physiological significance, as pre-exposure of donor cells to FasL improved the radioprotective qualities of hematopoietic progenitors, resulting in superior survival of myeloablated hosts. Under these conditions, the activity of long-term reconstituting cells was not affected, as determined in sequential secondary and tertiary transplants. Dual caspase-independent tropic and caspase-dependent apoptotic signaling place the Fas receptor at an important junction of activation and death. This regulatory mechanism of hematopoietic homeostasis activates progenitors to promote the recovery from aplasia and converts into a negative regulator in distal stages of cell differentiation.

Disclosure of potential conflicts of interest is found at the end of this article.
Subchronic organismal toxicity, cytotoxicity, genotoxicity, and feeding response of pacific oyster (Crassostrea gigas) to lindane (γ-HCH) exposure under experimental conditions
Authors: Anguiano Gerardo , Llera-Herrera Raul , Rojas Emilio , Vazquez-Boucard Celia
Published: September 2007

This study evaluated organismal toxicity, cytotoxicity, and genotoxicity and the filtration rate in response to different concentrations of subchronic lindane (gamma-hexachlorocyclohexane [γ-HCH]), exposure (12 d) in adult Pacific oysters Crassostrea gigas. Oysters were exposed in vivo in laboratory aquaria to 10 different concentrations (0.0–10.0 mg/L) of γ-HCH. The median lethal concentration (LC50) after 12 d was calculated as 2.22 mg/L. Cytotoxic effects were observed in hemocytes, where the mean cell viability was significantly decreased at 1.0 mg/L of γ-HCH after 12 d. Genotoxicity of γ-HCH measured by single cell gel electrophoresis assay, in hemocytes was evident at 0.7 mg/L of γ-HCH after 12 d. After 4 h of exposure to γ-HCH, filtration rates were reduced compared with controls to 65.8 and 38.2% at concentrations of 0.3 and 0.7 mg/L, respectively, and after 11 d of exposure, filtration rates were reduced to 60.4 and 30.9% at concentrations of 0.1 mg/L and higher. These results show the subchronic effects of γ-HCH at different concentrations and effect sensitivities are categorized as filtration rate < genotoxicity < cytotoxicity < mortality. The relevance of integral toxicity evaluation, considering different endpoints from molecular, cellular, and individual levels is discussed.
Acute and chronic toxicity of technical-grade pesticides to glochidia and juveniles of freshwater mussels (unionidae)
Authors: Bringolf Robert B. , Cope W. Gregory , Eads Chris B. , Lazaro Peter R. , Barnhart M. Christopher , Shea Damian
Published: September 2007

Chemical contaminants are among many potential factors involved in the decline of freshwater mussel populations in North America, and the effects of pesticides on early life stages of unionid mussels are largely unknown. The objective of this study was to determine the toxicity of technical-grade current-use pesticides to glochidia and juvenile life stages of freshwater mussels. We performed acute toxicity tests with glochidia (five species) and juveniles (two species) exposed to a suite of current-use pesticides including herbicides (atrazine and pendimethalin), insecticides (fipronil and permethrin), and a reference toxicant (NaCl). Because of limited availability of test organisms, not all species were tested with all pesticides. Toxicity tests with fungicides (chlorothalonil, propiconazole, and pyraclostrobin) were performed with one species (Lampsilis siliquoidea). Lampsilis siliquoidea glochidia and juveniles were highly sensitive to the fungicides tested but the technical-grade herbicides and insecticides, at concentrations approaching water solubility, were not acutely toxic to this or the other unionid species. In a 21-d chronic test with four-month-old juvenile L. siliquoidea, the 21-d median effective concentration (EC50) with atrazine was 4.3 mg/L and in atrazine treatments ≥3.8 mg/L mussel growth was significantly less than controls. The relatively high sensitivity of L. siliquoidea to chlorothalonil, propiconazole, and pyraclostrobin is similar to that reported for other aquatic organisms commonly used for toxicity testing. The relative risk associated with acute exposure of early life stages of mussels to technical-grade atrazine, pendimethalin, fipronil, and permethrin is likely low; however, survival and growth results with juvenile L. siliquoidea indicate that chronic exposure to high concentrations (≥3.8 mg/L) of atrazine may have the potential to impact mussel populations and warrants further investigation.
Evaluation of laboratory assays for the assessment of leaching of copper and chromium from ground-contact wood
Authors: García-Valcárcel Ana I. , Tadeo José L.
Published: September 2007

Laboratory studies were conducted to assess the leaching of Cu and Cr from wood, treated with a Cu-Cr-B preservative, when placed in contact with soil. Two laboratory assays were performed: Wood in contact with soil solutions over 30 d, and wood in direct contact with soil over 30 weeks. The influence of several factors, such as soil type and fertilizer use, was studied in both assays. In addition, the effect of soil moisture content and temperature was evaluated when wood was in contact with soil. A discrepancy in the results of the laboratory assays was observed. Leaching of Cu and Cr increased when soil in contact with wood was fertilized, but only an increase of Cu leaching was observed when soil solutions from fertilized soils were used. Moreover, soil solutions from a sandy clay loam soil produced a higher Cu leaching than those from a loamy sand soil, whereas the contrary occurred when treated wood was in direct contact with these soils. In the assay of treated wood in ground contact, the highest metal losses were produced in fertilized soils maintained at constant temperature and high soil moisture content, the latter being the most important factor. These losses were in the range of 5.34 to 15.6% for Cu and 1.85 to 2.35% for Cr in the soils studied. The proposed laboratory assay, using treated wood in direct contact with soil at a moisture content near field capacity during a period of 30 weeks, produced total metal losses that were in accordance with those reported by other authors under field conditions, expressed on a per-year basis.
Application of 1-D Convolutional Modeling to Interpretation of Ground Penetrating Radar Profiles-Turbidite Channel Sandstone 1, Lewis Shale, Wyoming
Authors: Young Roger Adams , Staggs Julie G. , Slatt Roger M. , Van Dam Rembe
Published: September 2007

Complex stratigraphic relationships, distinct lithologic facies, and variable bed thickness characterize channel-levee elements of turbidite sections examined in outcrop. The 3-D configuration of these features in the subsurface cannot be determined accurately using only logs in sparsely distributed and unevenly spaced boreholes. The missing interborehole information can be filled in by three-dimensional GPR surveys so long as the geological elements can be recognized in the data. This recognition can be aided by 1-D convolutional waveform modeling, which is able to separate multiples and refracted events from primary reflections, to predict severe amplitude loss due to attenuation in shales, to constrain reflection polarities and traveltimes, and to elucidate the role of interference within thin sandstone beds. Two-dimensional GPR profiles and a 3-D GPR survey image the lowermost and largest of a series of laterally offset, vertically stacked channel sandstones of the Lewis Shale, near Dad, WY. We combine measured sections, borehole logs, and cuttings to form a one-dimensional, blocked framework into which are embedded the laboratory-measured electrical properties of four facies. Zero-offset, non-dispersive impulse responses are computed and convolved with the waveform used in the surveys to produce synthetic radargrams. Modeling applies a frequency-independent attenuation and includes multiples up to second order. These synthetics are compared to nearby GPR sections that have been datum static-corrected using differential GPS elevations. The present modeling makes possible the interpretation of four features of major geological significance—the base of channel, the top of a shale-clast conglomerate, a featureless sandstone, and eroded channel∕levee mounds (erosional remnants). This case history shows that the use of 1-D models can reveal internal consistency among geological mapping, borehole information, laboratory measurements, and radar stratigraphy.
Experimental Monitoring of Cr(VI) Bio-Reduction Using Electrochemical Geophysics
Authors: Canan Birsen , Olhoeft Gary R. , Smith William A.
Published: September 2007

Many Department of Energy (DOE) sites are contaminated with highly carcinogenic hexavalent chromium (Cr(VI)). In this research, we explore the feasibility of applying complex resistivity to the detection and monitoring of microbially-induced reduction of hexavalent chromium (Cr(VI)) to a less toxic form (Cr(III)). We hope to measure the change in ionic concentration that occurs during this reduction reaction. This form of reduction promises to be an attractive alternative to more expensive remedial treatment methods. The specific goal of this research is to define the minimum and maximum concentration of the chemical and biological compounds in contaminated samples for which the Cr(VI)-Cr(III) reduction processes could be detected via complex resistivity. There are three sets of experiments, each comprised of three sample columns. The first experiment compares three concentrations of Cr(VI) at the same bacterial cell concentration. The second experiment establishes background samples with, and without, Cr(VI) and bacterial cells. The third experiment examines the influence of three different bacterial cell counts on the same concentration of Cr(VI). A polarization relaxation mechanism was observed between 10 and [Formula: see text]. The polarization mechanism, unfortunately, was not unique to bio-chemically active samples. Spectral analysis of complex resistivity data, however, showed that the frequency where the phase minimum occurred was not constant for bio-chemically active samples throughout the experiment. Significant shift in phase minima occurred between [Formula: see text] from the initiation to completion of Cr(VI) reduction. This phenomenon was quantified using the Cole-Cole model and the Marquardt-Levenberg nonlinear least square minimization method. The data suggest that the relaxation time and the time constant of this relaxation are the Cole-Cole parameters most sensitive to changes in biologically-induced reduction of Cr(VI).
Capacitive Resistivity Imaging with Towed Arrays
Authors: Kuras Oliver , Meldrum Philip I. , Beamish David , Ogilvy Richard D. , Lala Deepak
Published: September 2007

The capacitive resistivity (CR) technique is a generalization of the conventional DC resistivity method that facilitates measurements of electrical resistivity on engineered surfaces and highly resistive ground. The CR methodology allows the use of towed sensor arrays, thus enabling the rapid collection of high-resolution resistivity data. Under quasi-static conditions, CR data are equivalent to galvanic DC measurements so that CR datasets can be interpreted with conventional DC inversion algorithms. In this study, we demonstrate that the methodology and fundamental parameters of the CR technique facilitate spatial sampling at the centimeter scale for towing speeds of the order of [Formula: see text]. We argue that the dipole-dipole array is the most suitable geometry for dynamic CR measurements and present example data acquired with a prototype instrument using plate-wire combinations arranged in an equatorial geometry. The information content of raw CR data is found to be dominant over towing-induced noise and a direct comparison with DC profile data shows good agreement between both techniques. Based on these findings, we show that tomographic imaging is possible using datasets acquired with moving arrays. Closer investigation of the practical aspects of towed-array capacitive resistivity imaging (CRI) highlights the similarities with galvanic multi-electrode surveys, but the different geometric constraints and sampling regime of CRI give rise to advantages (high lateral resolution) as well as disadvantages (limitations in vertical resolution). We conclude our study with recommendations for practical CRI survey procedures and present a field example where we have successfully imaged a subsurface target in 3D. Towed-array CRI is found to provide equivalent (and in some ways superior) information about the shallow subsurface when compared to DC ERT (electrical resistivity tomography); it therefore widens the scope of electrical imaging surveys to environments where the conventional methodology would be impractical.
A Recent Swedish Attempt to Weaken State Control and Strengthen School Autonomy: The Experiment with Local Time Schedules
Authors: Rönnberg Linda
Published: September 2007

In 1999, after a series of far-reaching reforms aiming at decentralisation, deregulation and increased local autonomy in Swedish education, the Government decided to introduce a five-year experiment, which would develop these reform efforts even further. Even though Swedish compulsory schools already were the most autonomous in Europe with regard to decision making on school time, an experiment which allowed schools to freely decide time allocation and time management was launched. At least on paper, the experiment indicates a shift from state control to local autonomy, allowing school professionals to be free to make decisions on time distribution previously controlled by the state. The aim is to analyse and discuss whether the experiment has affected school autonomy or not and how this can be understood. The theoretical point of departure is a two-dimensional view of autonomy, where both freedom of action and capacity for action need to be taken into account. The freedom of action (the discretionary space for local actors) provided within the experiment is analysed through three properties of the experimental programme: programme clarity, division of responsibilities and control mechanisms. The schools' capacity for action concerns the extent participating schools make use of the discretion provided within the experiment. This is analysed in three schools with reference to their ability to organise themselves in a flexible way, as well as to what extent the schools have shown previous capacity for action and readiness for reform. Based on this analysis of the experiment, it is concluded that if reform efforts are made to increase school autonomy, they should not one-sidedly be focused on increasing local actors' freedom of action (such as abolishing the national time schedule). Such efforts should also be accompanied by measures to reinforce local actors' capacity for action. Unless local actors can make use of the discretion given to them by a superior (political) body, local autonomy will be far less than was intended, since freedom to act exceeds the actual capacity to act.
Colorants for Foods
Authors: Marmion Daniel ,   Updated by Staff
Published: September 2007

This article includes a brief history of the use of colorants in foods and the development of legislation in the United States to control them. It describes where and why colorants are used, lists all those currently in use, identifies each as either needing certification or not, and describes the chemical and physical properties, method of manufacture, chemical structure, chemical classification, and uses of each. Individual and general restrictions relating to the use of colorants are described, and sample specifications are shown. Includes references and sources for more information regarding colorants including their analysis as is and in product matrices.
Milk and Milk Products
Authors: Hall Carl W. ,   Updated by Staff
Published: September 2007

Hall, Carl W. (Engineering Information Services). Milk from cows is a significant food source throughout the world. Milk provides food components to meet important nutritional needs of the human body. Vitamins, minerals, sugar, fat, and protein are contained in milk. The amount of these components in milk varies with the breed of animal, the particular animal, and with other species that produce milk. As a human food, care must be taken in the production and processing of milk and milk products to maintain quality. Contamination must be avoided. Appropriate temperature control must be provided to hold raw milk, process milk into beverage, process milk into its many products, and deliver quality products to the consumer. Changing consumer habits influence the kind and amount of products manufactured. Appropriate quality determinations and controls must be provided throughout the process to assure that safe, nutritious products are delivered to the consumer on an economical basis.
Nitriles
Authors: DeVito Stephen C.
Published: September 2007

Nitriles are cyano‐substituted organic compounds, ie, organic derivatives of hydrogen cyanide. The combination of unique physical properties imparted by the nitrile group and the ease with which nitrile groups can be converted to other functional groups has made organonitrile compounds commercially important substances. Organonitriles may be prepared by a variety of methods including metathesis of organohalides, ammoxidation of hydrocarbons, dehydration of amides, and addition of hydrogen cyanide to unsaturated organic compounds such as aldehydes, ketones, and olefins. Some of the more common transformations include hydrolysis or alcoholysis to produce amides, acids and esters, and hydrogenation to produce amines, which are intermediates for the production of polyurethanes and polyamides. Nitriles are generally toxic to the extent that they may be metabolized in the body to liberate cyanide, and care in the body to liberate cyanide and care should be taken to prevent skin contact, oral ingestion or inhalation of vapors. This article addresses the following organonitrile compounds in some detail: acetonitrile, adiponitrile, a‐aminonitriles, azobisnitriles, benzonitrile, cyanoacetic acid (and esters), isophthalonitrile, methylglutaronitrile, pentenenitriles, and fatty acid nitriles.
Digital Filters
Authors: Diniz Paulo S. R. , Petraglia Mariane R.
Published: September 2007

The sections in this article are

Digital Filters

Sampling Rate

Frequency Response

Difference Equations

Finite Impulse Response Filters

Infinite Impulse Response Filters

Wave Digital Filters

Lattice Filters

Quantization Effects in Digital Filters

Digital Filter Implementation
Popular culture and critical media literacy in adult education: Theory and practice
Authors: Tisdell Elizabeth J.
Published: September 2007

This chapter introduces the volume, provides an overview of the theory and literature on popular culture and critical media literacy in education, and discusses ways to use popular culture in adult education.
Using the simpsons to teach humanities with gen X and gen Y adult students
Authors: Fink Maxwell A. , Foote Deborah C.
Published: September 2007

This chapter discusses how the animated show The Simpsons can be used successfully to present and critique various concepts normally found in traditional undergraduate Humanities courses.
The avengers, public pedagogy, and the development of British women's consciousness
Authors: Wright Robin Redmon
Published: September 2007

This chapter discusses the long‐term impact on British women of the popular 1960s television show The Avengers and explores strategies for utilizing popular culture to facilitate learning in the classroom.
Popular culture, cultural resistance, and anticonsumption activism: An exploration of culture jamming as critical adult education
Authors: Sandlin Jennifer A.
Published: September 2007

This chapter examines popular culture as a site of cultural resistance. Specifically, it explores how “culture jamming,” a cultural‐resistance activity, can be a form of adult education.
The Influence of Popular Culture and Entertainment Media on Adult Education
Authors: Thompson Patricia M.
Published: September 2007

This chapter summarizes the main themes in this volume: the role of popular culture and entertainment media in facilitating critical media literacy with adult learners; the influence of popular culture on our understanding of ourselves and others; and the ways in which popular culture reinforces or resists the dominant culture.
Aggressive Langerhans cell histiocytosis following T‐ALL: Clonally related neoplasms with persistent expression of constitutively active NOTCH1
Authors: Rodig Scott J. , Payne Ethan G. , Degar Barbara A. , Rollins Barrett , Feldman Andrew L. , Jaffe Elaine S. , Androkites Arlene , Silverman Lewis B. , Longtine Janina A. , Kutok Jeffery L. , Fleming Mark D. , Aster Jon C.
Published: September 2007

Langerhans cell histiocytosis (LCH) and related entities are neoplasms of unknown pathogenesis. Here, we describe studies assessing the role of NOTCH1 mutations in LCH, which were based on a case of fatal Langerhans cell tumor after T‐cell acute lymphoblastic leukemia (T‐ALL). Although the two types of neoplasm in this patient were temporally and pathologically distinct, molecular analyses showed that they harbored the same T‐cell receptor gene rearrangements and two activating NOTCH1 mutations involving exons 27 and 34. The exon 27 mutation altered a conserved cysteine residue in the N‐terminal portion of the NOTCH1 heterodimerization domain, while the mutation in exon 34 introduced a premature stop codon that results in the deletion of C‐terminal negative regulatory PEST domain. Analysis of cDNA prepared from the aggressive Langerhans cell tumor showed that the NOTCH1 mutations were aligned in cis, a configuration that caused synergistic increases in NOTCH1 signal strength in reporter gene assays. Immunohistochemistry confirmed that the Langerhans cell tumor also expressed NOTCH1 protein. Although these data suggested that NOTCH1 mutations might contribute to the pathogenesis of typical sporadic LCH and related neoplasms occurring in the absence of T‐ALL, an analysis of 24 cases of LCH and Rosai–Dorfman Disease occurring in patients without an antecedent history of T‐ALL revealed no mutations. Thus, activating NOTCH1 mutations appear to be unique to aggressive Langerhans cell tumors occurring after T‐ALL. Persistent expression of NOTCH1 in such tumors suggests that Notch pathway inhibitors could have a role in the treatment of these unusual neoplasms. Am. J. Hematol., 2008. © 2007 Wiley‐Liss, Inc.
The prognostic significance of leukemic cells clearance kinetics evaluation during the initial course of induction therapy with HAD (homoharringtonine, cytosine arabinoside, daunorubicin) in patients with de novo acute myeloid leukemia
Authors: Xiao Zhijian , Xue Hua , Li Rui , Zhang Li , Yu Minghua , Hao Yushu
Published: September 2007

The impact of the percentage of residual leukemic cells (RLCs) at the end of first course of induction chemotherapy (T1) or during aplasia (T2) on complete remission (CR) rate, disease‐free survival (DFS), and overall survival (OS) were retrospectively analyzed in 72 cases of de novo acute myeloid leukemia (AML) treated with HAD (homoharringtonine, cytosine arabinoside, and daunorubicin) regimen. The patients were separated into two subgroups by a cutoff of 10% bone marrow leukemic cells at T1 or T2 time point. The CR rate, DFS, and OS were significantly different between the two groups. We further confirmed that the percentage of RLCs at T1 or T2 is an independent prognostic factor of AML. Am. J. Hematol., 2008. © 2007 Wiley‐Liss, Inc.