bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Tank Wall Color and Up‐welling Water Flow on Growth and Survival of Eurasian Perch Larvae (Perca fluviatilis)
Authors: Jentoft Sissel , ØXnevad Sigurd , Aastveit Are H. , Andersen ØIvind 
Published: August 2006

AbstractThe influence of tank wall color and up‐welling water flow on growth and survival of Eurasian perch larvae (Perca fluviatilis) was tested in an intensive culture system. Newly hatched larvae were fedArtemianauplii, later combined with dry feed, and reared for 5 wk in either black tanks with up‐welling water flow or in gray tanks with or without up‐welling water flow. The perch larvae grew significantly faster in black tanks than in gray tanks regardless of water flow. Two weeks after hatching, a significantly higher mean weight was shown in larvae reared in black tanks compared to larvae reared in gray tanks with up‐welling water flow, and after 4 wk, the mean weight was significantly higher than in both of the other treatments. The difference in growth was further enhanced during the last week of the experiment, and the final mean weights were 51.1 ± 1.9 mg in black tanks with up‐welling water flow, 23.8 ± 2.1 mg in gray tanks with up‐welling water flow, and 23.7 ± 2.2 mg in gray tanks without up‐welling water flow. The cumulative mortality at the end of the experiment averaged 75% in all treatment groups. Taken together, the enhanced growth of Eurasian perch larvae in black tanks could be explained by high prey contrast and increased prey consumption. Up‐welling water flow had no impact on growth and survival of the perch larvae in gray tanks, indicating that the availability and consumption of the prey were independent of water movement.
Dual Receiver Concept for Solar Towers up to 100 MW
Authors: Eck M. , Buck R. , Wittmann M. 
Published: August 2006

Abstract
The dual receiver concept presented in this paper improves the adaptation of the central receiver to the steam cycle in a solar thermal power plant. By combination of an open volumetric air heater and a tubular evaporator the dual receiver concept profits from the advantages of these two concepts while their characteristic problems are avoided. The water is evaporated directly in the tubular steam generator; preheating and superheating are done in heat exchangers by using the hot air from the volumetric receiver. This paper presents a concept study that extends previous work on the 10MWel level (Buck et al., 2004, “Dual Receiver Concept for Solar Towers,” Proc. 12th Solar PACES Int. Symposium, Oct. 6–8, Oaxaca, Mexico) to a level of 100MWel, which is the expected power range of future plants. The results confirm the benefits of the new concept, resulting from higher thermal efficiency of the receiver and lower parasitic power consumption. The annual mean efficiency is increased from 13% to 16%. Advantageous are also the reduced thermal loads in the receiver components.
Two distinct fungi colonize roots and rhizomes of the myco-heterotrophic Afrothismia gesnerioides (Burmanniaceae)
Authors: Imhof Stephan 
Published: August 2006

The subterranean organs of Afrothismia gesnerioides H. Maas consist of short rhizomes densely covered with ovoid root tubercles, each of which may extend into a short filiform root extension. Serial sections revealed the presence of two distinct fungi occupying different niches within the plant tissues. Rhizomes and roots are divided into separate compartments hosting different morphotypes of the aseptate, exclusively intracellular hyphae of fungus A: (i) straight and persistent hyphae in the root epidermis, root extension, and outer rhizome cortex, (ii) coiled but still persistent hyphae in the third root layer, (iii) coiled hyphae undergoing degeneration in the root cortical parenchyma, (iv) starch depositions in the inner rhizome cortex and no colonization by fungus A, and (v) a partly collapsed root hypodermis serving as compartment barrier. The colonization by fungus A is interpreted as an aberrant arbuscular mycorrhiza of the Paris type. The compartmentation allows the separation of tissues where the hyphae stay functional from those in which the fungal material is digested. This pattern may represent a complex but efficient strategy for a sustained benefit from the few fungal penetrations that occur. Comparison with earlier work on Afrothismia winkleri (Engl.) Schltr. revealed considerable differences between the mycorrhizae that are interpreted as evolutionary steps. There are signs that these changes even may have improved the mycorrhizal benefit for the plant. The monomorphic hyphae of fungus B are smaller in diameter, septate, grow inter- as well as intra-cellularly, but are always characteristically appressed to the inner cell walls. It does not change its appearance within the root/rhizome compartments as does fungus A. Neither hyphal degeneration nor interferences with fungus A, starch depositions, or alterations in the development of A. gesnerioides could be noticed. Fungus B possibly is a commensal, but relevance to the symbiosis cannot be ruled out.
An assessment of genetic diversity in Desmodium sumichrastii (Fabaceae) of central Mexico
Authors: Bedolla-Garcia Brenda Y. , Lara-Cabrera Sabina I. 
Published: August 2006

The genus Desmodium contains ca. 450 species, distributed in Eastern Asia, Mexico, and Brazil, with 40 endemic species in Mexico, including Desmodium sumichrastii (Schinder) Standley. Randomly amplified polymorphic DNA (RAPD) variation was used to assess genetic variation within and among five populations of D. sumichrastii from west-central Mexico, constituting the first assessment in the tribe Desmodieae. Ninety percent of all bands were polymorphic for the 10 decamer RAPD primers used. Sixty-one percent of the variation was within populations, and 39% was among them. This pattern of higher variation within than among populations is unusual, but can be attributed to ethological characteristics of pollinators. The unweighted pair-group method with arithmetic averages (UPGMA) dendrogram based on Nei's genetic distances plots populations from Jalisco together, whereas populations from Aguililla in the neighboring state of Michoacan are separated and next to the San Miguel del Monte population (also in Michoacan). However, the dendrogram based on Dice's similarity coefficient calculated for all individuals separately groups the populations from Aguililla. We also found a significant correlation between genetic and geographic distances, which is in agreement with Dice's UPGMA dendrogram, where closer populations are more genetically similar. Interestingly the most diverse populations are located within a Biosphere Preserve, and the least diverse populations are located in heavily disturbed sites.
Composition and function of biological soil crust communities along topographic gradients in grasslands of central interior British Columbia (Chilcotin) and southwestern Yukon (Kluane)
Authors: Marsh Janet , Nouvet Sabine , Sanborn Paul , Coxson Darwyn 
Published: August 2006

Grasslands in the rainshadow of the Chilcotin (British Columbia) and St. Elias (Kluane, Yukon) mountain ranges of western Canada are characterized by widely spaced clumps of bunchgrass and sage, between which can be found lichen-dominated biological soil crusts (BSC). Our examination of Chilcotin and Kluane grasslands showed differential BSC development along topographic gradients, favoring those sites with lower levels of soil disturbance. Lichen species richness was greatest in upper topographic positions, that is, on valley side terraces in the Chilcotin and esker slopes in Kluane. Common BSC lichens in both grasslands included Acarospora schleicheri, Caloplaca tominii , Collema tenax , Diploschistes muscorum , Fulgensia bracteata , Phaeorrhiza nimbosa , Placidium squamulosum , and Psora decipiens . Chilcotin BSC additionally contained many Cladonia species (e.g., C. carneola , C. chlorophaea , C. pyxidata ), particularly where vegetation had encroached on BSC. The potential for nitrogen fixation by Collema -dominated crusts in Kluane was examined using acetylene reduction assays (ARA) and soil surface microclimate monitoring. ARA activity was highly dependent upon the duration of wetting events, reaching C2H4 levels up to 63 μmol·m–2·h–1after 40 h of hydration. Given the abundance of Collema-dominated crusts in Kluane and the optimal conditions for ARA activity that are reached during wetting–drying transitions, we hypothesized that BSC communities potentially make an important contribution to ecosystem nitrogen budgets. Enrichment in total and mineralizable N, as well as 15N natural abundance values, was consistent with N fixation making an important contribution to soil N pools in these ecosystems. Both Chilcotin and Kluane BSC had similar spongy microstructures that contrasted with the platy microstructures of the underlying surface mineral soils, but only the latter site showed micromorphological evidence of burial of mosses and other BSC components by continuing loess deposition. BSC may have performed similar roles in analogous steppe-like ecosystems that existed under full-glacial conditions in the unglaciated areas of eastern Beringia in Alaska and Yukon.
Structural characterization of the stigma-style complex of Cynara cardunculus (Asteraceae) and immunolocalization of cardosins A and B during floral development
Authors: Duarte Patrícia , Figueiredo Raquel , Pereira Susana , Pissarra José 
Published: August 2006

Studies were carried out on the structure of the stigma and style of Cynara cardunculus L. (cardoon) during flower development. The stigma is of the dry type with a papillate cuticularized epidermis. During development, the unicellular papillae become match-stick shaped, cuticularize, and show an increase in vacuolar volume. In mature papillae, two morphologically different vacuoles were observed, one electron-dense and the other electron-transparent, putatively corresponding to distinct vacuolar populations. These vacuoles label differently for cardosin A, specifically detected in the electron-dense compartments. The style is solid with a cuticularized epidermis and a central core of transmitting tissue (TT) several cell layers thick. The TT cells show abundant rough endoplasmic reticulum and Golgi bodies, associated with active secretion. During maturation, TT cells become increasingly separated by a polysaccharide-rich extracellular matrix. Communication between TT cells is maintained via plasmodesmata in longitudinal walls. Distribution of cardosins A and B in developing C. cardunculus flowers was also characterized. The presence of aspartic proteinases (APs) in flowers is unusual, generally occurring at low levels. Cardosins A and B are always present in cardoon florets and localize at distinct pistil levels: stigma (papillae) and style (TT), respectively. This differential localization suggests distinct biological functions for cardosins, most likely essential for reproduction in this species.
Phylogeny of the genusLotus(Leguminosae, Loteae): evidence from nrITS sequences and morphology
Authors: Degtjareva G.V. , Kramina T.E. , Sokoloff D.D. , Samigullin T.H. , Valiejo-Roman C.M. , Antonov A.S. 
Published: August 2006

Lotus (120–130 species) is the largest genus of the tribe Loteae. The taxonomy of Lotus is complicated, and a comprehensive taxonomic revision of the genus is needed. We have conducted phylogenetic analyses of Lotus based on nrITS data alone and combined with data on 46 morphological characters. Eighty-one ingroup nrITS accessions representing 71 Lotus species are studied; among them 47 accessions representing 40 species are new. Representatives of all other genera of the tribe Loteae are included in the outgroup (for three genera, nrITS sequences are published for the first time). Forty-two of 71 ingroup species were not included in previous morphological phylogenetic studies. The most important conclusions of the present study are (1) addition of morphological data to the nrITS matrix produces a better resolved phylogeny of Lotus; (2) previous findings that Dorycnium and Tetragonolobus cannot be separated from Lotus at the generic level are well supported; (3) Lotus creticus should be placed in section Pedrosia rather than in section Lotea; (4) a broad treatment of section Ononidium is unnatural and the section should possibly not be recognized at all; (5) section Heinekenia is paraphyletic; (6) section Lotus should include Lotus conimbricensis; then the section is monophyletic; (7) a basic chromosome number of x = 6 is an important synapomorphy for the expanded section Lotus; (8) the segregation of Lotus schimperi and allies into section Chamaelotus is well supported; (9) there is an apparent functional correlation between stylodium and keel evolution in Lotus.
Effects of wild rice (Zizania palustris) straw on biomass and seed production in northern Minnesota
Authors: Durkee Walker Rachel , Pastor John , Dewey Bradley W. 
Published: August 2006

Wild rice ( Zizania palustris L.) litter accumulation may inhibit plant growth and production both by physically suppressing seedling emergence and by nitrogen immobilization in fresh litter. This latter mechanism could reduce nitrogen availability to plants early in the growing season at a period when more than half of the annual uptake occurs. To test the importance of these mechanisms, we planted wild rice in mesocosms. Half the tanks were planted with seeds sown below the litter and half were planted with seedlings grown to a height taller than litter thickness. One-third of the tanks were treated with fresh (nitrogen immobilizing) litter, one-third were treated with litter that had been incubated for 26 d and was mineralizing nitrogen, and one-third did not receive litter. These treatments resulted in a fully crossed factorial design, with nine replicates for each treatment combination, totaling 54 tanks. We measured plant growth, vegetative, root, and seed biomass, total plant N, and available N at 2.5 cm sediment depth. The presence of litter and its stage of decay caused plant, root, and seed biomass, and seed and total plant nitrogen content to increase. We found no physical inhibition of litter on the potential growth of plants started as seeds. Therefore, the timing of litter nitrogen immobilization or mineralization affects the potential growth of wild rice.
A PCR-based method to detect species of Gondwanamyces and Ophiostoma on surfaces of insects colonizing Protea flowers
Authors: Roets Francois , Wingfield Michael J. , Dreyer Léanne L. , Crous Pedro W. , Bellstedt Dirk U. 
Published: August 2006

Flower heads of economically important members of the genus Protea L. mature into conspicuous, often long-lived infructescences, which in South Africa are commonly colonized by species of the ophiostomatoid fungi Gondwanamyces G.J. Marais & M.J. Wingfield and Ophiostoma Syd. & P. Syd. It is suspected that these fungi are transported between infructescences by insects. To develop techniques that would enable detection of ophiostomatoid fungi on insects, primers GPR1 and OSP1 were designed based on unique 28S ribosomal DNA sequences of Gondwanamyces and Ophiostoma from Protea. Multiplex polymerase chain reaction of these primers, combined with universal primer LR6, yielded fragment lengths of 885 and 637 bp. Positive amplification was achieved from as little as 30 and 45 pg of fungal genomic DNA for Gondwanamyces and Ophiostoma, respectively, and fragments of identical lengths were amplified from insects artificially inoculated with these fungi. No other tested fungal species showed amplification with GPR1 or OSP1 and LR6. Using these primers two insect species ( Genuchus hottentottus Fabricius and Oxycarenus maculates Stal.) collected from Protea repens L. infructescences were confirmed as carriers of Gondwanamyces proteae (M.J. Wingfield et al.) G.J. Marais & M.J. Wingfield and Ophiostoma splendens G.J. Marais & M.J. Wingfield, respectively. The method developed in this study represents a rapid detection system that can be used to understand the relationship between insects and ophiostomatoid fungi found associated with flowers of South African species of Protea .
Design and Progress of a Trial of Selenium to Prevent Prostate Cancer among Men with High-Grade Prostatic Intraepithelial Neoplasia
Authors: Marshall James R. , Sakr Wael , Wood David , Berry Donna , Tangen Catherine , Parker Felicia , Thompson Ian , Lippman Scott M. , Lieberman Ronald , Alberts David , Jarrard David , Coltman Charles , Greenwald Peter , Minasian Lori , Crawford E. David 
Published: August 2006

AbstractHigh-grade prostatic intraepithelial neoplasia (HGPIN) is generally regarded as a premalignant lesion that progresses toward prostate cancer. In light of the significant sequelae of prostate cancer treatment, prevention is desirable, and men with HGPIN would be suitable, high-risk subjects. There is in vitro, in vivo, epidemiologic, and human experimental evidence that selenium supplementation may protect against prostate cancer. This article introduces the rationale for, and progress to date, of a double-blind, randomized, placebo-controlled trial of selenium supplementation (200 μg/d in the form of selenomethionine), to prevent the development of prostate cancer among men with HGPIN. The trial, Southwest Oncology Group Protocol 9917, funded by a National Cancer Institute program supporting pivotal prevention trials has registered 537 patients and has randomized &gt;380 to date. Subject accrual is expected to be completed by the fall of 2006, with trial completion in 2009. (Cancer Epidemiol Biomarkers Prev 2006;15(8):1479–84)
Associations among Mammographic Density, Circulating Sex Hormones, and Polymorphisms in Sex Hormone Metabolism Genes in Postmenopausal Women
Authors: Warren Ruth , Skinner Jane , Sala Evis , Denton Erika , Dowsett Mitch , Folkerd Elizabeth , Healey Catherine S. , Dunning Alison , Doody Deborah , Ponder Bruce , Luben Robert N. , Day N.E. , Easton Douglas 
Published: August 2006

Abstract
Mammographic density and serum sex hormone levels are important risk factors for breast cancer, but their associations with one another are unclear. We studied these phenotypes, together with single nucleotide polymorphisms (SNP) in genes related to sex hormone metabolism, in a cross-sectional study of 1,413 postmenopausal women from the European Prospective Investigation into Cancer and Nutrition-Norfolk. All women were &gt;1 year postmenopausal and had not taken hormone replacement therapy for &gt;3 months before sampling. Serum levels of 7 sex hormones [estradiol, testosterone, sex hormone-binding globulin (SHBG), androstenedione, 17-OH-progesterone, estrone, and estrone sulfate] and 15 SNPs in the CYP17, CYP19, EDH17B2, SHBG, COMT, and CYP1B1 genes were studied. Mammograms nearest in time to the blood sampling were identified through the national breast screening program and visually assessed by three radiologists using the Boyd six-category and Wolfe four-category scales. We found a weak positive association between mammographic density and SHBG levels (P = 0.09) but no association with any other hormones. None of the SNPs, including those shown previously to be associated with estradiol or SHBG, showed significant associations with density. We conclude that mammographic density is largely independent of postmenopausal steroid hormone levels, indicating that these risk factors have, to a large extent, an independent etiology and suggesting that they may be independent predictors of breast cancer risk. (Cancer Epidemiol Biomarkers Prev 2006;15(8):1502-08)
Chromosomal Instability in Barrett's Esophagus Is Related to Telomere Shortening
Authors: Finley Jennifer C. , Reid Brian J. , Odze Robert D. , Sanchez Carissa A. , Galipeau Patricia , Li Xiaohong , Self Steven G. , Gollahon Katherine A. , Blount Patricia L. , Rabinovitch Peter S. 
Published: August 2006

AbstractBarrett's esophagus is a useful model for the study of carcinogenesis, as the metaplastic columnar epithelium that replaces squamous esophageal epithelium is at elevated risk for development of adenocarcinoma. We examined telomere length and chromosomal instability (CIN) in Barrett's esophagus biopsies using fluorescence in situ hybridization. To study CIN, we selected centromere and locus-specific arm probes to chromosomes 17/17p (p53), 11/11q (cyclin D1), and 9/9p (p16 INK4A), loci reported to be involved in early stages of Barrett's esophagus neoplasia. Telomere shortening was observed in Barrett's esophagus epithelium at all histologic grades, whereas CIN was highest in biopsies with dysplastic changes; there was, however, considerable heterogeneity between patients in each variable. Alterations on chromosome 17 were strongly correlated with telomere length (r = 0.55; P &lt; 0.0001) and loss of the 17p arm signal was the most common event. CIN on chromosome 11 was also associated with telomere shortening (r =0.3; P = 0.05), although 11q arm gains were most common. On chromosome 9p, arm losses were the most common finding, but chromosome 9 CIN was not strongly correlated with telomere length. We conclude that CIN is related to telomere shortening in Barrett's esophagus but varies by chromosome. Whether instability is manifested as loss or gain seems to be influenced by the chromosomal loci involved. Because telomere shortening and CIN are early events in Barrett's esophagus neoplastic progression and are highly variable among patients, it will be important to determine whether they identify a subset of patients that is at risk for more rapid neoplastic evolution. (Cancer Epidemiol Biomarkers Prev 2006;15(8):1451–7)
Flavonoids and Colorectal Cancer in Italy
Authors: Rossi Marta , Negri Eva , Talamini Renato , Bosetti Cristina , Parpinel Maria , Gnagnarella Patrizia , Franceschi Silvia , Dal Maso Luigino , Montella Maurizio , Giacosa Attilio , La Vecchia Carlo 
Published: August 2006

Abstract
Because of their several biological activities, flavonoids may have an important role in explaining the protective effects of vegetables, fruit, and, possibly, tea against cancer. The potential relation between flavonoids and colorectal cancer risk was investigated using data from a multicentric Italian case-control study, including 1,953 cases of colorectal cancers (1,225 colon cancers and 728 rectal cancers) and 4,154 hospital controls admitted for acute nonneoplastic diseases. We have applied recently published data on the composition of foods and beverages, in terms of six principal classes of flavonoids, on dietary information collected through a validated food-frequency questionnaire. Odds ratios (OR) were estimated by multiple logistic regression models, including terms for sex, age, study center, family history of colorectal cancer, education, alcohol consumption, body mass index, physical activity, and energy intake. A reduced risk of colorectal cancer was found for increasing intake of isoflavones (OR, 0.76, for the highest versus the lowest quintile, Ptrend = 0.001), anthocyanidins (OR, 0.67, Ptrend &lt; 0.001), flavones (OR, 0.78, Ptrend = 0.004), and flavonols (OR, 0.64, Ptrend &lt; 0.001). No significant association was found for flavan-3-ols (OR, 0.98), flavanones (OR, 0.96), and total flavonoids (OR, 0.97). The estimates did not substantially differ for colon and rectal cancers, as well as in strata of sex, age, and body mass index. The findings of this large study provide support for an inverse association of selected classes of flavonoids with colorectal cancer risk. (Cancer Epidemiol Biomarker Prev 2006;15(8):1555–8)