bluuebunny/crossref_metadata_2025_split huggingface dataset:
An experimental study of grain scale melt segregation mechanisms in two common crustal rock types
Authors: Holyoke C. W. , Rushmer T. 
Published: March 2003

AbstractCreation of pathways for melt to migrate from its source is the necessary first step for transport of magma to the upper crust. To test the role of different dehydration‐melting reactions in the development of permeability during partial melting and deformation in the crust, we experimentally deformed two common crustal rock types. A muscovite‐biotite metapelite and a biotite gneiss were deformed at conditions below, at and above their fluid‐absent solidus. For the metapelite, temperatures ranged between 650 and 800 °C at Pc=700 MPa to investigate the muscovite‐dehydration melting reaction. For the biotite gneiss, temperatures ranged between 850 and 950 °C at Pc=1000 MPa to explore biotite dehydration‐melting under lower crustal conditions. Deformation for both sets of experiments was performed at the same strain rate (ε.) 1.37×10−5 s−1. In the presence of deformation, the positive ΔV and associated high dilational strain of the muscovite dehydration‐melting reaction produces an increase in melt pore pressure with partial melting of the metapelite. In contrast, the biotite dehydration‐melting reaction is not associated with a large dilational strain and during deformation and partial melting of the biotite gneiss melt pore pressure builds more gradually. Due to the different rates in pore pressure increase, melt‐enhanced deformation microstructures reflect the different dehydration melting reactions themselves. Permeability development in the two rocks differs because grain boundaries control melt distribution to a greater extent in the gneiss. Muscovite‐dehydration melting may develop melt pathways at low melt fractions due to a larger volume of melt, in comparison with biotite‐dehydration melting, generated at the solidus. This may be a viable physical mechanism in which rapid melt segregation from a metapelitic source rock can occur. Alternatively, the results from the gneiss experiments suggest continual draining of biotite‐derived magma from the lower crust with melt migration paths controlled by structural anisotropies in the protolith.
High‐pressure granulites: formation, recovery of peak conditions and implications for tectonics
Authors: O'Brien P. J. , Rötzler J. 
Published: March 2003

AbstractHigh‐pressure granulites are characterised by the key associations garnet‐clinopyroxene‐plagioclase‐quartz (in basic rocks) and kyanite‐K‐feldspar (metapelites and felsic rocks) and are typically orthopyroxene‐free in both basic and felsic bulk compositions. In regional metamorphic areas, two essential varieties exist: a high‐ to ultrahigh‐temperature group and a group representing overprinted eclogites. The high‐ to ultrahigh‐temperature type formerly contained high‐temperature ternary feldspar (now mesoperthite) coexisting with kyanite, is associated with garnet peridotites, and formed at conditions above 900 °C and 1.5 GPa. Clinopyroxene in subordinate basic rocks is Al‐rich and textural evidence points to a high‐pressure–high‐temperature melting history. The second variety contains symplectite‐like or poikilitic clinopyroxene‐plagioclase intergrowths indicating former plagioclase‐free, i.e. eclogite facies assemblages. This type of rock formed at conditions straddling the high‐pressure amphibolite/high‐pressure granulite field at around 700–850 °C, 1.0–1.4 GPa. Importantly, in the majority of high‐pressure granulites, orthopyroxene is secondary and is a product of reactions at pressures lower than the peak recorded pressure. In contrast to low‐ and medium‐pressure granulites, which form at conditions attainable in the mid to lower levels of normal continental crust, high‐pressure granulites (of nonxenolith origin) mostly represent rocks formed as a result of short‐lived tectonic events that led to crustal thickening or subduction of the crust into the mantle. Short times at high‐temperature conditions are reflected in the preservation of prograde zoning in garnet and pyroxene. High‐pressure granulites of both regional types, although rare, are known from both old and young metamorphic terranes (e.g. c. 45 Ma, Namche Barwa, E Himalaya; 400–340 Ma, European Variscides; 1.8 Ga Hengshan, China; 1.9 Ga, Snowbird, Saskatchewan and 2.5 Ga Jianping, China). This spread of ages supports proposals suggesting that thermal and tectonic processes in the lithosphere have not changed significantly since at least the end of the Archean.
Nontransplant Therapy for Dialysis‐Related Amyloidosis
Authors: Copley John B. , Lindberg Jill S. 
Published: March 2003

ABSTRACTThere is no specific treatment for dialysis‐related amyloidosis (DRA). Available therapy is directed at removal of large quantities of β2‐microglobulin (β2M) and palliation of symptoms. Plasma concentrations of β2M in end‐stage renal disease (ESRD) depend on the degree of residual renal function, the type of blood purification therapy, and properties of the dialysis filtration membrane. Retention of β2M appears to be a necessary, although not sufficient, condition for DRA. While preserving residual renal function is important, dialysis modality largely determines β2M removal. Convective dialysis treatments (hemofiltration and hemodiafiltration) remove β2M more efficiently than diffusive treatments (conventional dialysis). In addition, column adsorption of β2M can extensively remove the molecule, as can nocturnal hemodialysis. Hemodialysis membrane properties that are particularly important with regard to β2M removal include permeability, adsorptive capacity, and biocompatibility. As such, β2M removal with highly permeable biocompatible membranes such as polysulfone and polyacrylonitrile is relatively large. Several studies have suggested that use of such membranes can significantly delay DRA development and may be useful in ameliorating DRA‐associated symptoms. Non‐dialysis‐related therapy for DRA is palliative and includes both medical and surgical therapies. Medical therapy includes low‐dose corticosteroids and nonsteroidal anti‐inflammatory drugs (NSAIDs). Surgical therapy consists of relief of carpal tunnel syndrome, or palliation of shoulder pain, destroyed weight‐bearing joints, or spinal cord compression. DRA is a serious complication of long‐term dialysis. It is important for nephrologists to recognize the condition and attempt to slow its progression.
Review Articles: Inflammation in End‐stage Renal Disease: Sources, Consequences, and Therapy
Authors: Stenvinkel Peter , Alvestrand Anders 
Published: March 2003

AbstractCardiovascular disease (CVD) remains the main cause of morbidity and mortality in patients with end‐stage renal disease (ESRD). Although traditional risk factors are common in ESRD patients, they alone may not be sufficient to account for the high prevalence of CVD in this condition. Recent evidence demonstrates that chronic inflammation, a nontraditional risk factor which is commonly observed in ESRD patients, may cause malnutrition and progressive atherosclerotic CVD by several pathogenetic mechanisms. The causes of inflammation in ESRD are multifactorial and, while it may reflect underlying CVD, an acute‐phase reaction may also be a direct cause of vascular injury by several pathogenetic mechanisms. Available data suggest that proinflammatory cytokines play a central role in the genesis of both malnutrition and CVD in ESRD. Thus it could be speculated that suppression of the vicious cycle of malnutrition, inflammation, and atherosclerosis (MIA syndrome) would improve survival in dialysis patients. Recent evidence has demonstrated strong associations between inflammation and both increased oxidative stress and endothelial dysfunction in ESRD patients. As there is not yet any recognized, or even proposed, treatment for ESRD patients with chronic inflammation, it would be of obvious interest to study the long‐term effect of various anti‐inflammatory treatment strategies on the nutritional and cardiovascular status as well as outcome in these patients.
Comparative Review of the Pharmacokinetics of Vitamin D Analogues
Authors: Bailie George R. , Johnson Curtis A. 
Published: March 2003

AbstractThis article reviews the pharmacokinetic characteristics of calcitriol, paricalcitol, and doxercalciferol, and provides an overview of the metabolism of vitamin D. Calcitriol and paricalcitol have similar pharmacokinetic profiles, with terminal half‐lives ranging from 5 to 10 hours in healthy subjects to 15–30 hours in patients undergoing dialysis. Both are active on intravenous administration and little of the active agent remains in the circulation after 24 hours, although they are normally given every 48–72 hours. Doxercalciferol is a prohormone, requiring hepatic metabolism to the active metabolite 1α,25‐(OH)2D2. The half‐life of 1α,25‐(OH)2D2 is about 34 hours in healthy subjects and about 45 hours in dialysis patients, resembling physiologic blood concentrations of endogenous vitamin D. More studies are warranted to determine the disposition of the vitamin D analogues, especially in selected populations such as pediatric and geriatric dialysis patients.
Amplified in Breast Cancer‐1 Glutamine Repeat and Prostate Cancer Risk
Authors: Platz Elizabeth A. , Giovannucci Edward , Brown Myles , Cieluch Carsta , Shepard Timothy F. , Stampfer Meir J. , Kantoff Philip W. 
Published: March 2003

ABSTRACTObjectives: Amplified in breast cancer‐1 (AIB1) is a steroid receptor coactivator that enhances estrogen‐dependent transcriptional activation by the estrogen receptor. It is unknown whether AIB1 also interacts with the androgen receptor. Because the development and progression of prostate cancer is likely to be partially mediated by steroid hormones, we investigated whether a polymorphic CAG/CAA repeat encoding glutamine in the AIB1 gene is related to prostate cancer risk in a nested study of 581 patients and 786 age‐matched control subjects in the Physicians' Health Study.Materials and Methods: DNA was extracted from peripheral whole blood, and the region encompassing the repeat was amplified using fluorescent‐labeled primers. The fragments were run on polyacrylamide gels and sized by computer software. We estimated the relative risk (RR) of prostate cancer for AIB1 glutamine repeat length from logistic regression models controlling for the matching variables.Results: Three glutamine repeat lengths were prevalent: 29 (47.8% among control subjects), 28 (38.5% among control subjects), and 26 (12.6% among control subjects). Compared to 29 repeats, the RR of prostate cancer was 0.92 (95% confidence interval [CI] 0.72–1.17) for 26 repeats and 1.01 (95% CI 0.86–1.19) for 28 repeats. Compared to 28/29, the RR of prostate cancer was not significantly altered for any of the other common genotypes. No clear associations were present for AIB1 glutamine repeat length genotype by stage at the diagnosis/histologic grade of the tumor.Conclusion: This study does not support an important role in prostate cancer incidence or aggressiveness of AIB1 glutamine repeat length in the range observed in this predominately white cohort.
PSP94: Evaluation of Prognostic Utility in Patients Treated with Radiotherapy for Nonmetastatic Prostate Cancer
Authors: Bauman G. S. , Xuan J. , Chin J. , Sakai H. , Guo Y. , Garde S. , Fraser J. , Venkatesan V. M. 
Published: March 2003

ABSTRACTObjectives: Conflicting reports exist as to the utility of PSP94 in the diagnosis and management of prostate cancer. We have identified serum‐bound forms of PSP94 in prostate cancer patients. To further evaluate the usefulness of this finding, we measured bound and free serum PSP94 levels in patients with nonmetastatic prostate cancer before radiotherapy.Materials and Methods: Pretreatment levels of free PSP94 in 42 patients were measured in serum via a competitive enzyme‐linked immunosorbent assay. Levels of bound PSP94 were measured by a semiquantitative assay after fractionation of total serum proteins by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis and Western blot analysis. Pretreatment levels of prostate specific antigen (PSA) were measured by a commercially available assay. Archival sera from 42 patients and a subgroup of 27 patients with “favorable” pretreatment PSA values (i.e., < 10 ng/ml) were statistically analyzed. Pretreatment levels of PSP94 (free and bound) and PSA, as well as tumor stage and grade, were correlated with treatment outcome (biochemical relapse‐free survival) postradiotherapy.Results: Pretreatment PSA and the ratio of bound to free PSP94 were significant predictors of relapse postradiotherapy on univariate analysis. An elevated ratio of bound to free PSP94 was a stronger predictor (p = 0.0074) of relapse postradiotherapy compared with PSA level (p = 0.070) in a subgroup of prostate cancer patients with “favorable” pretreatment PSA levels.Conclusions: The results presented here indicate that serum PSP94‐bound complexes must be considered in evaluating the clinical utility of PSP94 as a prostate cancer marker. A higher ratio of bound to free PSP94 may indicate worse outcome postradiotherapy. Differential testing of serum PSP94 has shown that it, in addition to PSA, may be of prognostic value for patients receiving radiotherapy for nonmetastatic prostate cancer.
Experimental Restoration of Native Vegetation in Indiana Dunes National Lakeshore
Authors: Choi Young D. , Pavlovic Noel B. 
Published: March 2003

AbstractWe investigated the effects of prescribed fire, herbicide treatment, and sod removal on the eradication of exotic grasses and the establishment of native plant species in 24 experimental restoration plots in three razed residential sites within the boundary of Indiana Dunes National Lakeshore. During 1992–1995, herbicide treatment and sod removal decreased the combined cover ofPoa pratensis(Kentucky blue grass) andAgropyron repens(quackgrass) significantly (from 82% to 13%, and 85% to 8%, respectively), whereas fire did not suppress such exotic lawn grasses. In 1993, several opportunistic species, represented byCyperusspp. (umbrella sedges),Digitaria sanguinalis(crab grass), andAmbrosia artemisiifolia(common ragweed), filled the gaps left by the removal of lawn grasses. For the same period, Detrended Correspondence Analysis revealed a clear vegetation divergence between the control‐fire plots and the herbicide‐sod removal plots. WhilePoa pratensisandAgropyron repenscontinued to dominate the control and fire plots, the planted native species, represented bySchizachyrium scoparium(little blue‐stem),Sorghastrum nutans(Indian grass),Rudbeckia hirta(black‐eyed Susan), andMonarda punctata(horsemint), began to dominate in the herbicide and sod removal plots from 1994. In both herbicide and sod removal plots, the ground cover of grasses (68%) was much higher than the forbs (10%). The herbicide plots, where exotic species were removed but nitrogen‐rich top soils were not removed, showed a higher diversity of planted native species than the sod removal plots (where both exotic species and top soils were removed) and the control‐fire plots (where neither was removed). This finding suggests that an optimum but not excessive concentration of soil nitrogen is needed to support a maximum species diversity in such infertile substrate as sandy soil. In addition, the decrease in potassium in all plots, regardless of treatment, suggests that potassium may become a limiting factor for our restored native vegetation.
Restoration of Riverine Forest at Hall Branch on Phosphate‐Mined Land, Florida
Authors: Clewell Andre F. 
Published: March 2003

AbstractI describe a 1.5‐ha riverine headwater forest (Hall Branch) that was created 11 years earlier on phosphate‐mined and reclaimed land near Tampa, Florida, U.S.A. Favorable hydrologic and edaphic conditions were realized, owing to the proper positioning of the project site in an effectively reclaimed landscape. The soil had developed a distinct A horizon and an incipient B horizon. Planted trees, mainly species of Acer, Fraxinus, Ilex, Liquidambar, Magnolia, Persea, Quercus, Taxodium, and Ulmus, shared dominance with short‐lived volunteer willows (Salix caroliniana) that had already begun to senesce. The tree canopy exhibited 85% cover, and some trees had grown to 12.5 m tall. Basal area reached 8.31 m2/ha for trees 10 cm or more in diameter at breast height. Ten planted tree species produced seeds and yielded seedlings. The floristic composition over the decade consisted of 22 species of trees and 208 shrubs, vines, epiphytes, ferns, graminoids, and forbs. Thirty‐eight non‐arboreal species were directly transplanted, others arose from a seed bank in muck that was amended on wetter sites, and the rest volunteered via natural dissemination. The frequency of non‐arboreal plants was collectively 98%. Seventy‐three species at the restoration site were characteristic of the mature, undisturbed reference ecosystem. A corresponding area within the reference ecosystem contained essentially the same number of species and the same array of life forms. Copious plant reproduction has transformed the planted forest into an intact ecosystem that no longer needs restoration assistance.
Restoration of a Native Grassland as Habitat for the Golden Sun Moth Synemon plana Walker (Lepidoptera; Castniidae) at Mount Piper, Australia
Authors: O'Dwyer Cheryl , Attiwill Peter M. 
Published: March 2003

Abstract Synemon plana (golden sun moth) is a small diurnal moth from the family Castniidae, now listed as endangered in all regions of southeastern Australia in which it occurs. This study details an attempt to restore the native grassland habitat of S. plana at one site by increasing the cover of its probable food plant, Austrodanthonia eriantha (wallaby grass), to at least 40%, the average percentage cover determined from all currently inhabited sites. The percentage cover of A. eriantha increased when seedlings were planted, although there was no significant increase in cover by seeding caryopsides (dispersal units) or by weeding. However, combining weeding with planting seedlings, or seeding increased cover by 22% and 27% to 43% and 64%, respectively. Two hundred caryopsides per square meter (compared with only 49 seedlings/m2) were required to increase cover to at least 40% due to the low viability of seeds and low germination in the field. Therefore, to restore grasslands dominated by A. eriantha as suitable habitat for S. plana, seedlings should be planted and weeds removed.
Local Mangrove Planting in the Philippines: Are Fisherfolk and Fishpond Owners Effective Restorationists?
Authors: Walters Bradley B. 
Published: March 2003

AbstractLocal fisherfolk and fishpond owners have been practicing “restoration” of mangrove forests in some parts of the Philippines for decades, well before governments and non‐government organizations began to promote the activity as a conservation tool. This paper examines ecological characteristics of these mangrove plantations and compares them to natural mangroves in the same areas. Mangrove planters were interviewed and plantation and natural mangrove forests were surveyed to measure forest structure, composition and regeneration. Compared with natural forests, mangrove plantations were characterized by high densities of small stems, shorter and narrower canopies, and fewer species. For both economic and ecological reasons, the vast majority of people dispersed and planted only Rhizophora mucronata/stylosa and, furthermore, they often thinned other species out of planted areas. There was remarkably little subsequent recruitment of other, nonplanted mangrove species into plantations up to 50 and 60 years of age. This pattern held across a diversity of sites, including plantations that had not been selectively cut or weeded. Important ecological and economic benefits result from local mangrove planting, but catalyzing diverse forest regeneration—at least in the short to medium term—is not one of them. The lesson: if you want to restore diverse mangrove forests, you have to plant diverse mangrove forests.
Ecological Restoration of Native Forest at Aratiatia, North Island, New Zealand
Authors: Smale Mark C. , Whaley Patrick T. , Smale Paul N. 
Published: March 2003

AbstractSuccessional pathways in native forest, planted 15–33 years ago on reconstructed surfaces to restore aesthetic values destroyed by hydro‐electric dam construction at Aratiatia, central North Island, New Zealand, were compared with those on similar surfaces left unplanted. Only native species were planted. Classification identified three canopy communities and several ground layer communities with significant inter‐stratum relationships: Pittosporum tenuifolium‐Sophora tetraptera short forest with ground layers dominated by litter; P. tenuifolium‐Kunzea ericoides short forest over adventive grasses on planted sites; and adventive Cytisus scoparius shrubland over grasses on unplanted sites. Planted communities mirror young secondary forests on intact substrates in the district, but have lower density and similar or higher basal area than such forests elsewhere. Established seedlings of seven planted canopy trees, mostly early successional bird‐dispersed species, are reasonably widespread in floristically rich Pittosporum‐Sophora forest. Seedlings of only two species are widespread in floristically poor Pittosporum‐Kunzea forest, and none on unplanted sites. This first large‐scale attempt at ecological restoration in New Zealand, by mass planting of new surfaces with early successional native woody species, has created aesthetically‐pleasing stands of indigenous forest on sites which would otherwise remain in relatively stable adventive shrubland communities for the foreseeable future. Only continued monitoring will show whether further management is necessary and whether natural processes are operating at a level sufficient to ensure that artificially initiated successions will continue along more or less natural pathways.
Does Extensive Grazing Benefit Butterflies in Coastal Dunes?
Authors: WallisDeVries Michiel F. , Raemakers Ivo 
Published: March 2003

AbstractGrazing at low stocking rates has become a common management practice in nature restoration projects in the Netherlands. However, detailed knowledge of grazing impact is often poor, in particular for invertebrates. This study addressed the impact of extensive grazing on butterflies. Butterflies are critical indicators of habitat quality for many plant and animal species. We compared monitoring data from 1992 to 1996 for calcareous coastal dune areas in the Netherlands with different management: 11 grazed areas, 7 ungrazed areas and 4 areas managed by annual cutting. Grazing typically concerned year‐round grazing by cattle and/or ponies, at low stocking rates (0.05–0.26 head ha−1 yr−1). Butterfly abundance was related to species composition and structure of the vegetation. Changes in butterfly abundance were positive in grazed and ungrazed areas compared to cut areas. Species richness was not affected by management, but individual species differed in their response. Species from open grassland benefited most from grazing, particularly Issoria lathonia (Queen of Spain Fritillary) and Lycaena phlaeas (Small Copper). No clear negative effects of grazing were observed, but species occurrence was not always positively related to the environmental characteristics associated with grazing. In the long run, even lower stocking rates might prove more beneficial to the butterfly community as a whole. Four of the more frequently observed species, I. lathonia, Hipparchia semele (Grayling), Pyrgus malvae (Grizzled Skipper) and Aricia agestis (Brown Argus), are listed as threatened to susceptible in the Netherlands. All were apparently favored by grazing. It is concluded that extensive grazing has good potential to enhance butterfly diversity in restoration projects.