bluuebunny/crossref_metadata_2025 huggingface dataset:
Minimizing protein insolubilization during thermal inactivation of lipoxygenase in soybean cotyledons
Authors: Brown B. D. , Wei L. S. , Steinberg M. P. , Villota R.
Published: September 2007

The objective was to develop a procedure for inactivating lipoxy‐genase in soybean cotyledons without losing protein solubility. The approach was to moisten cotyledons to one of 2 levels in soft water or carbonate buffers, steam for a short time, hold for a definite period at a known temperature, cool and analyze for enzyme activity and protein solubility. Temperature dependence of both inactivation and insolubilization kinetics was determined. Increasing temperature of steaming and holding favored our objective. At 16.3% moisture, the pH 9.8 buffer was beneficial but the pH 10.8 buffer was not. The holding period was not beneficial compared to steaming alone. Recommended conditions were adjustment of cotyledon moisture to 16.3% with pH 9.8 buffer and then heating in steam for about 10 sec; at temperatures of 91 C and above, 99% of the lipoxygenase could be inactivated with retention of over 70% protein solubility. The effect of buffers on kinetics of heat inactivation and insolubilization appeared to be related to the states of hydration water, i.e., the presence of solute water at the higher moisture content.
A Rapid Synthesis of Fatty Acyl Urea Derivatives
Authors: Micich T. J.
Published: September 2007

Fat‐based aliphatic amides react with aromatic isocyanates in refluxing xylene generally within 1 hr to form crystalline acylaryl urea compounds in 50‐80% yields. The reaction appears to be general with either component being aliphatic or aromatic. Although the reaction occurs in various solvents, xylene is the preferred solvent in which the reactions were completed within 4 hr for the chosen amides and isocyanates. The progress of the reaction was conveniently monitored by infrared through the disappearance of the intense isocyanate band at 2258 cm−1.
Mafura Nut Oil and Meal: Processing and Purification
Authors: Fupi V. W. K. , Mork P. C.
Published: September 2007

The seeds of the tropical tree known as mafura (Trichilia emetica) contain significant amounts of oil and protein. So far, commercial use of the mafura seeds has been prevented by the presence of a strong bitter and emetic taste, as well as a brownish color in both oil and meal. A refining procedure which gives edible oil with acceptable organoleptic properties has been developed. The raw meal has been extracted with aqueous alcohol to give a debittered meal with a protein content of about 36%. The amino acid composition of the meal was found to be comparable to that of other vegetable food proteins, except for a relatively low content of sulfur‐containing amino acids. The brown color has been shown to result from browning reactions taking place during storage and processing. Most of the color may be removed by repeated treatments with dilute sodium hydroxide, followed by bleaching with earth and activated carbon.
Cyclopropenoid Fatty Acid Content and Iodine Value of Crude Oils from Indian Cottonseed
Authors: Pandey S. N. , Suri L. K.
Published: September 2007

Cyclopropenoid fatty acid (CPFA) and iodine value (IV) of oils extracted from 30 varieties of cottonseed belonging to 4 botanical species, Gossypium arboreum, G. herbaceum, G. hirsutum and G. barbadense, have been reported. The CPFA determined by HBr titration method ranged from 0.66 to 1.51%. The IV of the oils ranged from 93.3 to 111.2. CPFA contents were significantly different among the species and nonsignificant within the species. The mean values of CPFA for different species were 0.67 (G. bar‐badense), 0.83 (G. hirsutum), 1.14 (G. berbaceum) and 1.40% (G. arboreum). There was no correlation between IV and CPFA content.
Synthesis of EDTA‐monoalkylamide chelates and evaluation of the surface‐active properties
Authors: Takeshita Toshio , Shimohara Taka‐Aki , Maeda Shigeru
Published: September 2007

New chelating agents were synthesized from long‐chain amines and ethylenediaminetetraacetic acid (EDTA) monoanhydride which was prepared by partial hydrolysis of EDTA anhydride. The equivalent reactions between the chelating agents and several metal ions gave the corresponding 1:1 metal chelates in good yield. These chelates and the sodium salts of the chelating agents were found to have good surface active properties, especially dispersing power and emul‐sifying power.
Effect of quaternary ammonium substitution of hydroxyethylcellulose on binding of dodecyl sulfate
Authors: Ohbu K. , Hiraishi O. , Kashiwa I.
Published: September 2007

The binding behavior of sodium dodecyl sulfate (SDS) to quater‐nary ammonium substituted hydroxyethylcellulose (cationic cellu‐lose) of varying degree of substitution was studied by the following measurements: binding isotherms of SDS to cationic cellulose, dye solubilization of the cationic cellulose/SDS complex, partial molal volume of each cationic cellulose, and spin‐lattice relaxation time of SDS protons in the course of binding. Binding isotherms showed features similar to that observed for the globular protein/SDS system. The molecular processes of complex formation between cationic cellulose and SDS is discussed based on these results.
Progress report of the AOCS flavor nomenclature and standards committee
Authors: Waltking A. E.
Published: September 2007

Over the past 5 years, 2 collaborative studies have been organized to evaluate the gas liquid chromatographic (GLC) methods for flavor of edible oils. The most recent of these studies compared the results from 5 GLC procedures to the evaluations of the flavor panels of 8 laboratories. While the GLC procedures proved to be more precise than the panels, it was shown that separate correlation equations must be developed for each type of oil, each degree of hydrogenation or blending, and each manner of storage or abuse of the samples. Thus, either a flavor panel must always be available to establish a reference point for any study to be made, or GLC flavor methods must be recognized as providing a direct, but rela‐tive, evaluation for “oil quality.”
Land‐use conversion effects on CO2 emissions: from agricultural to hybrid poplar plantation
Authors: Saurette D. D. , Chang S. X. , Thomas B. R.
Published: September 2007

Land‐use changes such as deforestation have been considered one of the main contributors to increased greenhouse gas emissions, while verifiable C sequestration through afforestation projects is eligible to receive C credits under the Kyoto Protocol. We studied the short‐term effects on CO2 emissions of converting agricultural land‐use (planted to barley) to a hybrid poplar (Populusdeltoids × Populus × petrowskyana var. Walker) plantation in the Parkland region in northern Alberta, where large areas are being planted to hybrid poplars. CO2 emissions were measured using a static gas chamber method. No differences were found in soil temperature, volumetric moisture content, or soil respiration rates between the barley and Walker plots. The mean soil respiration rate in 2005 was 1.83 ± 0.19 (mean ± 1 SE) and 1.89 ± 0.13 μmol CO2 m−2 s−1 in the barley and Walker plots, respectively. However, biomass production was higher in the barley plots, indicating that the agricultural land‐use system had a greater ability to fix atmospheric CO2. The C balance in the land‐use systems were estimated to be a small net gain (before considering straw and grain removal through harvesting) of 0.03 ± 0.187 Mg C ha−1 year−1 in the barley plots and a net loss of 3.35 ± 0.080 Mg C ha−1 year−1 from the Walker poplar plots. Over the long‐term, we expect the hybrid poplar plantation to become a net C sink as the trees grow bigger and net primary productivity increases.
Binding Energy of Hydrogen-Like Impurities in Quantum Well Wires of InSb/GaAs in a Magnetic Field
Authors: Poghosyan B Zh
Published: September 2007

The binding energy of a hydrogen-like impurity in a thin size-quantized wire of the InSb/GaAs semiconductors with Kane’s dispersion law in a magnetic fieldB parallel to the wire axis has been calculated as a function of the radius of the wire and magnitude ofB, using a variational approach. It is shown that when wire radius is less than the Bohr radius of the impurity, the nonparabolicity of dispersion law of charge carriers leads to a considerable increase of the binding energy in the magnetic field, as well as to a more rapid growth of binding energy with growth ofB.
The Role of Intrinsic and Surface States on the Emission Properties of Colloidal CdSe and CdSe/ZnS Quantum Dots
Authors: Morello Giovanni , Anni Marco , Cozzoli PantaleoDavide , Manna Liberato , Cingolani Roberto , De Giorgi Milena
Published: September 2007

Time Resolved Photoluminescence (TRPL) measurements on the picosecond time scale (temporal resolution of 17 ps) on colloidal CdSe and CdSe/ZnS Quantum Dots (QDs) were performed. Transient PL spectra reveal three emission peaks with different lifetimes (60 ps, 460 ps and 9–10 ns, from the bluest to the reddest peak). By considering the characteristic decay times and by comparing the energetic separations among the states with those theoretically expected, we attribute the two higher energy peaks to ± 1
U
and ± 1
L
bright states of the fine structure picture of spherical CdSe QDs, and the third one to surface states emission. We show that the contribution of surface emission to the PL results to be different for the two samples studied (67% in the CdSe QDs and 32% in CdSe/ZnS QDs), confirming the decisive role of the ZnS shell in the improvement of the surface passivation.
Recall of lifestyle advice in patients recently hospitalised with heart failure: A EuroHeart Failure Survey analysis
Authors: Lainščak Mitja , Cleland John G.F. , Lenzen Mattie J. , Nabb Samantha , Keber Irena , Follath Ferenc , Komajda Michel , Swedberg Karl
Published: September 2007

Background

There are limited data on recall and implementation of lifestyle advice in patients with heart failure (HF).

Aim

To investigate what advice patients with HF recall being given, and whether they report following the advice they remember.

Methods and results

3261 patients with suspected HF participating in the EuroHeart Failure Survey were interviewed by a health professional 12weeks after hospital discharge. Patients recalled receiving 46% of pre‐specified items of advice and 67% reported that they followed these completely. Both recall (53%) and implementation (71%) was best in patients with left ventricular systolic dysfunction (LVSD). In multivariate analysis, younger age, male sex, patient awareness of the condition and patients reporting that they received a clear explanation of the diagnosis by a health professional, all factors associated with having LVSD, were the strongest predictors of recall.

Conclusions

Recall of and adherence to advice by patients with HF in this large European cross‐sectional survey was disappointing. Responsibility for patient education lies with health professionals who should ensure that patients receive and understand advice, and are able to recall and follow it. A greater awareness of the issues surrounding lifestyle advice and more evidence supporting its value could improve patient care.
Modulation of sensitized C‐fibers by adrenergic stimulation in human neuropathic pain
Authors: Schattschneider Jörn , Scarano Marco , Binder Andreas , Wasner Gunnar , Baron Ralf
Published: September 2007

The chronic constriction injury model is widely used in studying mechanisms of neuropathic pain. In this model neuropathic pain can be influenced by sympathetic interventions. It is assumed that similar mechanisms as in animals are responsible for pain arising from nerve entrapment syndromes in humans. The aim of the present study was to investigate if in patients with nerve entrapment nociceptive afferents can be modulated by adrenergic stimulation.

Methods: Twenty patients with pain due to a unilateral entrapment of the median nerve and 10 controls were included in the study. Spontaneous pain, mechanical and thermal evoked pain were assessed within the innervation territory of the lesioned nerve and the corresponding contralateral segment in patients and on the right hand side in healthy volunteers. The examinations were performed at baseline, during whole body cooling (sympathetic activation) and whole body warming (sympathetic inhibition), and after norepinephrine iontophoresis.

Results: All patients reported spontaneous pain. Mechanical allodynia, punctate hyperalgesia and cold allodynia was not found. According to side‐to‐side differences in heat pain thresholds, patients were separated in patients with (n=10) and without (n=10) heat hyperalgesia. Adrenergic stimulation did not induce or enhance spontaneous or mechanical evoked pain in any patient or control subject. However in patients with pre‐existing heat hyperalgesia sympathetic stimulation aggravated heat hyperalgesia significantly. Further in these patients the decrease in heat pain thresholds observed after norepinephrine iontophoresis was significantly higher compared to patients without pre‐existing heat hyperalgesia.

Conclusion: Sympathetic–afferent interaction does not play a major role in pain generation due to nerve entrapment. Nevertheless in a subgroup of patients nociceptive afferents show sensitivity to physiological and pharmacological sympathetic stimulation. This finding is important because it emphasises that despite there is no clinical detectable effect on pain sympathetic afferent interaction can be found.
Retrobulbar teratoma causing exophthalmos in a cat
Authors: Wray Jonathan D. , Doust Ross T. , McConnell Fraser , Dennis Ruth T. , Blunden Anthony S.
Published: September 2007

A 3-year female-neutered domestic shorthair cat presenting with exophthalmos and an ipsilateral subzygomatic soft tissue mass lesion is described. Magnetic resonance imaging of the mass was performed followed by complete surgical excision. The mass was determined to be a retrobulbar teratoma and complete resection was curative. Teratomas are rare germ-cell tumours that uncommonly form in extragonadal sites. A retrobulbar location has not been previously reported in the cat and should be considered a rare cause of exophthalmos in this species.
A short-term intervention trial with selenate, selenium-enriched yeast and selenium-enriched milk: effects on oxidative defence regulation
Authors: Ravn-Haren Gitte , Bügel Susanne , Krath Britta N. , Hoac Tien , Stagsted Jan , Jørgensen Karina , Bresson June R. , Larsen Erik H. , Dragsted Lars O.
Published: September 2007

Increased Se intakes have been associated with decreased risk of cancer and CVD. Several mechanisms have been proposed, including antioxidant effects through selenoproteins, induction of carcinogen metabolism and effects on the blood lipid profile. In a 4 × 1 week randomised, double-blind cross-over study, healthy young men supplemented their usual diet with selenate, Se-enriched yeast, Se-enriched milk or placebo (Se dose was 300 μg/d for selenate and Se-enriched yeast, and about 480 μg/d for Se-enriched milk) followed by 8-week washout periods. All Se sources increased serum Se levels after supplementation for 1 week. The effect of the organic forms did not differ significantly and both increased serum Se more than selenate. Conversely, thrombocyte glutathione peroxidase (GPX) was increased in the periods where subjects were supplemented with selenate but not in those where they were given Se-enriched yeast or Se-enriched milk. We found no effect on plasma lipid resistance to oxidation, total cholesterol, TAG, HDL- and LDL-cholesterol, GPX, glutathione reductase (GR) and glutathione S-transferase (GST) activities measured in erythrocytes, GPX and GR activities determined in plasma, or GR and GST activities in thrombocytes. Leucocyte expression of genes encoding selenoproteins (GPX1, TrR1 and SelP), and of electrophile response element-regulated genes (GCLC, Fra1 and NQO1) were likewise unaffected at all time points following intervention. We conclude that thrombocyte GPX is specifically increased by short-term selenate supplementation, but not by short-term supplementation with organic Se. Short-term Se supplementation does not seem to affect blood lipid markers or expression and activity of selected enzymes and a transcription factor involved in glutathione-mediated detoxification and antioxidation.
The Centre 3 layered gabbro intrusion, Ardnamurchan, NW Scotland
Authors: O'Driscoll B.
Published: September 2007

Detailed remapping of the Palaeogene Ardnamurchan Centre 3 gabbros, NW Scotland, suggests that this classic sequence of ring-intrusions forms a composite layered lopolith. The area mapped by previous studies as the Great Eucrite gabbro intrusion comprises 70% by area of Centre 3. Field observations suggest that most of the other smaller ring-intrusions of Centre 3 (interior to the Great Eucrite) constitute either distinct petrological facies of the same intrusion, or included country-rock or peridotite blocks. These observations, together with syn-magmatically deformed inward-dipping modal layering, are used here to support the interpretation that significant central sagging occurred in the intrusion at a late stage in its crystallization history.
Zircon ages of the metavolcanic rocks and metagranites of the Ollo de Sapo Domain in central Spain: implications for the Neoproterozoic to Early Palaeozoic evolution of Iberia
Authors: Montero P. , Bea F. , González-Lodeiro F. , Talavera C. , Whitehouse M. J.
Published: September 2007

Dating the pre-Middle Ordovician metavolcanic rocks and metagranites of the Ollo de Sapo Domain has, historically, been difficult because of the small compositional variation, the effects of the Variscan orogeny and, as revealed in this paper, the unusually high fraction of inherited zircon components. The first reliable zircon data (U–Pb ion microprobe and Pb–Pb stepwise evaporation) indicate that the Ollo de Sapo volcanism spanned 495±5 Ma to 483±3 Ma, and was followed by the intrusion of high-level granites from 483±3 Ma to 474±4 Ma. In both metavolcanic rocks and metagranites, no less than 70–80% of zircon grains are either totally Precambrian or contain a Precambrian core overgrown by a Cambro-Ordovician rim. About 80–90% of inherited zircons are Early Ediacaran (602–614 Ma) and derived from calc-alkaline intermediate to felsic igneous rocks generated at the end of the Pan-African arc–continent collision. In the Villadepera region, located to the west, both the metagranites and metavolcanic rocks also contain Meso-Archaean zircons (3.0–3.2 Ga) which ultimately originated from the West African Craton. In the Hiendelaencina region, located to the east, both the metagranites and metavolcanic rocks lack Meso-Archaean zircons, but they have two different inherited zircon populations, one Cryogenian (650–700 Ma) and the other Tonian (850–900 Ma), which suggest older-than-Ediacaran additional island-arc components. The different proportion of source components and the marked variation of the 87Sr/86Srinit. suggest, at least tentatively, that the across-arc polarity of the remnants of the Pan-African arc of Iberia trended east–west (with respect to the current coordinates) during Cambro-Ordovician times, and that the passive margin was situated to the west.
Miniature deep-sea hatchetfish (Teleostei: Stomiiformes) from the Miocene of Italy
Authors: CARNEVALE GIORGIO
Published: September 2007

A new genus and species of deep-sea hatchetfish,Discosternon federicaegen. et sp. nov., is described from the Middle Miocene (Serravallian) calciturbititic deposits of the Tufillo Unit exposed near the town of Gessopalena, central Italy. It is based on a single, very small, well-preserved and nearly complete specimen that exhibits a discoid physiognomy and a unique combination of features, many of which are reductive (loss of dorsal blade, loss of anal-fin hiatus, loss of abdominal keel-like structure, reduction of number of supraneurals, reduction of number of caudal vertebrae, presence of slender neural and haemal spines, external surface of cleithrum smooth). The comparative morphological analysis indicates thatDiscosternonis probably related to the derived generaHorbatshiaandSternoptyx. The highly reduced body size and the possession of many reductive characters indicate thatDiscosternoncan be presumed to be a miniature fish. Anatomical and morphofunctional considerations suggest thatDiscosternonpossibly was a midwater plankton feeder characterized by a reduced locomotory ability.
Significance of pre-epiglottic space invasion in supracricoid partial laryngectomy with cricohyoidopexy
Authors: Suoglu Y , Guven M , Kiyak E , Enoz M
Published: September 2007

Cancerous involvement of the pre-epiglottic space has been known for many years to be an important prognostic factor. The aim of this study was to investigate the prognostic value of pre-epiglottic space invasion, according to the degree of invasion (i.e. absence, minimal or gross), and to assess the oncological suitability for supracricoid partial laryngectomy in patients with supraglottic laryngeal carcinomas. This study included 52 patients with squamous cell carcinomas of the supraglottic and glotto-supraglottic larynx, treated with supracricoid partial laryngectomy–cricohyoidopexy, between 1992 and 2001. Clinical and histopathological parameters were evaluated. Pre-epiglottic space invasion was seen in 35 patients (67.3 per cent); there was gross invasion in seven patients and minimal invasion in 28. Neoplastic invasion of the anterior commissure was seen in 18 patients (34.6 per cent) and thyroid cartilage involvement in eight (15.4 per cent). Neoplastic spread through the extralaryngeal tissues was not seen in any patient. The five-year overall survival was 71.5 per cent for patients with gross pre-epiglottic space invasion, 82.2 per cent for those with minimal pre-epiglottic space invasion, and 76.4 per cent for those without pre-epiglottic space invasion. It was observed that gross or minimal pre-epiglottic space invasion did not have a statistically significant effect on survival. Univariate analysis showed that nodal positivity was associated with a poor prognosis. None of the other parameters analysed showed a statistically significant relationship with survival. Four (7.6 per cent) patients had local laryngeal recurrence. Distant metastasis and a second primary tumour were detected in three (5.8 per cent) and four (7.6 per cent) patients, respectively. The five-year overall survival and cause-specific survival were 78.8 and 82 per cent, respectively. Supracricoid partial laryngectomy with cricohyoidopexy can safely be performed in supraglottic and glotto-supraglottic carcinomas with minimal or gross invasion of the pre-epiglottic space which have no extralaryngeal spread. Nodal status is an important predictor affecting survival.
Male breast cancer – how to treat?
Authors: Rossmann E. D. , Liljegren A. , Bergh J.
Published: September 2007

Treatment principles of breast cancer in males are derived from studies performed among females, while the low incidence in males has so far precluded such studies. The therapy recommendations for males therefore lack the solid evidence, frequently present for females with breast cancer. The primary breast cancer diagnosis in males is not infrequently in stage III/IV and at higher age, thereby requiring multiprofessional and multimodal management including preoperative therapy and adjuvant therapies based on the tumour’s biological characteristics and the clinical circumstances. The majority of male breast cancer tumours are oestrogen-receptor positive and adjuvant/neoadjuvant tamoxifen is therefore recommended, surgery is frequently radical mastectomy and adjuvant radiotherapy should likely be used on wider indications. Chemotherapy should be considered both in the adjuvant and metastatic setting for receptor-negative cancers and for patients with biologically aggressive disease. Trastuzumab should be offered to patients with Her-2/neu-positive disease, while the use of aromatase inhibitors is more uncertain due to differences in the hormonal environment in males.
Temporal variability of the descent of high‐altitude NOX inferred from ionospheric data
Authors: Clilverd Mark A. , Seppälä Annika , Rodger Craig J. , Thomson Neil R. , Lichtenberger János , Steinbach Péter
Published: September 2007

In this study we investigate periods of enhanced ionization in the mesosphere during Northern Hemisphere wintertime. Long‐lasting ionization enhancements (days) are typically produced by solar proton events or by the descent of thermospheric NOX during periods of sustained downward vertical transport associated with a strong underlying polar vortex. Using a new application of ground‐based low‐frequency radio wave remote sensing, we study the mesospheric ionization conditions during the Northern Hemisphere winters spanning 2003–2004, 2004–2005, and 2005–2006. The winter 2003–2004 subionospheric radio wave propagation data from a transmitter in Iceland shows signatures of the descent of NOX through 80 km altitude starting on 13 January 2004, during the occurrence of a strong polar vortex, indicating a thermospheric source for the NOX. Similar analysis of radio wave propagation data in the Northern Hemisphere winter of 2004–2005 does not show a NOX descent event passing through the mesosphere, due to a lack of downward vertical transport as a result of a weak underlying polar vortex, despite the occurrence of significant solar proton ionization during January 2005. In 2005–2006 there were no significant ionization events and also no descent of significant amounts of thermospheric NOX, despite a strong polar vortex and strong vertical transport. We model the signature of the descent of NOX seen in the radio wave propagation data using the Sodankylä Ion Chemistry model, confirming that the levels of NOX in the mesosphere are ∼100 times the usual background levels. The combination of strong NOX sources in the thermosphere and also a strong polar vortex is required for NOX to descend into the stratosphere with significant concentration levels.
Three‐dimensional global simulation of interplanetary coronal mass ejection propagation from the Sun to the heliosphere: Solar event of 12 May 1997
Authors: Wu Chin‐Chun , Fry C. D. , Wu S. T. , Dryer M. , Liou Kan
Published: September 2007

A newly developed hybrid code, HAFv.2+3DMHD, that combines two simulation codes, Hakamada‐Akasofu‐Fry code version 2 (HAFv.2) and a fully three‐dimensional (3‐D), time‐dependent MHD simulation code, is used to study the global interplanetary coronal mass ejection (ICME) from the 12 May 1997 solar event. The solar wind structure is first simulated from the photosphere (1 solar radius, Rs) out to 2.5 Rs. The first step is derived from daily solar magnetograms. The HAFv.2 code is then used from 2.5 Rs to provide input at 18 Rs (0.08 AU) for the three‐dimensional MHD code that calculates the evolution of solar wind plasma and interplanetary magnetic field beyond this distance into the heliosphere. A dynamic disturbance, mimicking the flare's energy output from the 12 May 1997 solar event, is then delivered to this quiescent nonuniform heliospheric structure to model the evolution and interplanetary propagation of the ICME (including its shock). We compare the derived ICME velocity and number density with the Wind spacecraft observations near Earth. We integrate the line‐of‐sight density in the plane of sky to compare with the white light brightness data observed by the Large‐Angle Spectrometric Coronograph (LASCO) instrument on SOHO. This simulation will provide a tool to link the general cases of ICME at 1 AU to their solar sources, as well as to identify the possible origins of shock formation due to CMEs and CME/corotating interaction region interactions. In the case of complex or interacting ejecta, model interpretation is often required to accurately determine the solar sources of the ejecta at 1 AU. Because this newly developed model is performed using 3‐D MHD, its results can be extended to simulate coronal and heliospheric observations, including the ambient medium's nonuniformity provided by the HAFv.2 model, from the recently launched Solar Terrestrial Relations Observatory (STEREO) mission.
Transient fluvial incision in the headwaters of the Yellow River, northeastern Tibet, China
Authors: Harkins Nathan , Kirby Eric , Heimsath Arjun , Robinson Ruth , Reiser Uwe
Published: September 2007

We utilize topographic analysis of channel profiles combined with field measurements of erosion rates to explore the distribution of channel incision in the Anyemaqen Shan, a broad mountainous region in the northeastern Tibetan plateau. Tributary channels to the Yellow River display systematic downstream increases in channel gradient associated with convex upward longitudinal profiles. Steep lower reaches of channels are associated with rapid (>1 m/ka) incision rates along the Yellow River, while upstream reaches are associated with relatively slow (0.05–0.1 m/ka) erosion of soil‐mantled uplands. Covariance between erosion rates and channel steepness indices suggest that channels are adjusted to match long‐wavelength differential rock uplift across the range. Geologic constraints indicate that rapid incision downstream of the range is associated with excavation of basin fill driven by changes in relative base level farther downstream. The upstream limit of this wave of transient incision is marked by a series of knickpoints that are found at nearly the same elevation throughout the watershed, consistent with knickpoint migration as a kinematic, rather than diffusional, wave. Tributary channel gradients downstream of knickpoints, however, display a progressive adjustment to increased incision rates that may reflect the influence of increased sediment flux. Comparison of observed channel profiles to a stream power model of fluvial behavior reveals that the rate of knickpoint propagation can only be explained if the erosional efficiency coefficient (K) increases during incision. Our results thus highlight the utility of channel profile analysis to reconstruct the fluvial response to both active tectonism and external changes in base level.
Fluid pressurization due to frictional heating on a fault at a permeability contrast
Authors: Vredevoogd Michael A. , Oglesby David D. , Park Stephen K.
Published: September 2007

Frictional heating on a fault plane causes pore fluids to pressurize. When the permeability of the fault zone materials is sufficiently low, fluid pressure on the fault can approach the normal stress, though it can never be exceeded due to the feedback between pore pressure and frictional strength. However, if slip occurs at a boundary between materials of different permeabilities, such as fault gouge and a damage zone, the highest pressure develops within a few millimeters of the fault in the lower permeability material, rather than at the fault surface. The pressure increase off the fault can reach or exceed the normal stress given a large enough permeability contrast, because there is no direct feedback between this pressure and the frictional heating at the fault surface. High fluid pressures off the fault might result in the slip shifting into the lower permeability material, where the frictional strength has been reduced.
Variable intensity of teleconnections during the late Holocene in subtropical North America from an isotopic study of speleothem from Florida
Authors: van Beynen Philip E. , Asmerom Yemane , Polyak Victor , Soto Limaris , Polk Jason S.
Published: September 2007

The persistence and influence of both tropical and extra‐tropical teleconnections on the hydrology of subtropical North America are little understood. Major atmospheric‐oceanic controls on the isotopic composition of the precipitation reconstructed from a 1,000 year old stalagmite are the North Atlantic Oscillation (NAO) and the Pacific Decadal Oscillation (PDO). These teleconnections create decadal‐ to centennial‐scale changes in the seasonal distribution of precipitation. An increase in the winter proportion of annual precipitation coincides with negative phase NAO conditions and a positive phase PDO. However, the PDO's influence appears to be weakened when it is out of phase with the El Niño Southern Oscillation (ENSO). The NAO exerts the greater decadal influence on this regions climate than the El Niño Southern Oscillation (ENSO), suggesting a greater significance of high latitude controls on subtropical North America.
Persistent surface snowmelt over Antarctica (1987–2006) from 19.35 GHz brightness temperatures
Authors: Tedesco M. , Abdalati W. , Zwally H. J.
Published: September 2007

Persistent melting (e.g., continuing for more than three days or for one consecutive day and night) is mapped in Antarctica (1987–2006) using night‐ and day‐time Special Sensor Microwave Imager brightness temperatures (Tb) at 19.35 GHz, horizontal polarization. Snowmelt is indicated when Tb and relative daily difference exceed threshold values, respectively Tc and ΔT, computed for each pixel and year, or when both daytime and nighttime Tb exceed Tc. Results from an electromagnetic model suggest that the minimum detectable liquid water content ranges between 0.2 and 0.5%, in volume. We find that melting areas have been moving inland since 1987. A first‐time extensive melting (1987–2006) is detected over the Transantarctic Mountains on January 2005, 875 Km inland and 2000 m above sea level. Melting extent and index have been decreasing over Antarctica, since 1987, although either positive and negative trends are observed from a sub‐continental scale analysis.
Three‐dimensional simulation of the dynamical heliosphere
Authors: Labun Lance A. , Müller Hans‐Reinhard
Published: September 2007

The structure of the global heliosphere is driven not only by the properties of the respective interstellar plasma and neutral populations but also by the temporal and spatial variation of the solar wind plasma itself. Often assumptions of symmetry or stationarity are made for modeling the global heliosphere that greatly reduce the problem space. Here, an adaptation of a two‐fluid code to a fully realized three‐dimensional model of the heliosphere is presented. The boundary functions for the solar wind are derived from recently presented detailed observations and models of solar output by Whang et al. (2005). Neutrals are included as a single separate fluid interacting with the plasma through charge exchange. We first examine temporal and spatial variation of the solar wind separately and finally study a model containing both together. The asymmetric solar wind creates a heliosphere that is slightly elongated over the solar polar directions. Solar maximum conditions act as a pulse of dense material in the outer heliosphere, with fast responses of termination shock and heliopause locations. The pulse propagation in the heliosheath creates a dynamic environment, additionally triggering heliopause instabilities.
Energetic particles during the first and third Ulysses southern high‐latitude excursions: Probing global corotating interaction region structure beyond 5 AU
Authors: Lario D. , Roelof E. C.
Published: September 2007

We analyze energetic particle observations during the first and third ascents of Ulysses to the southern regions of the heliosphere. The first high‐latitude excursion occurred in the declining phase of solar cycle 22, while the third occurred in a later phase of solar cycle 23. In contrast to the long‐lived and well‐defined ∼26‐day recurrent intensity enhancements observed throughout the first southern excursion, observations during the third southern excursion showed a more variable structure. Transient events of solar origin were more abundant and intense. Corotating interaction regions (CIRs) were clearly present in intermittent sequences lasting only a few solar rotations. Within these sequences the relationships between solar wind structures and energetic particle events were remarkably similar to those observed in the steady recurrences of the first southern excursion. Energetic particles associated with well‐formed CIRs bounded by strong forward and reverse shock pairs were not observed until heliographic latitudes Λ ≳ 30°S (versus Λ ≳ 13°S in the first orbit). When Ulysses finally emerged into the fast (≳700 km s−1) solar wind at Λ ≥ 39°S, particle events were variable and either associated with weak reverse shocks or without solar wind signatures indicative of local CIRs (just as in solar cycle 22). The time‐intensity profiles in individual CIRs matched up well between the two southern excursions implying that essentially the same CIR structure existed in both solar cycles, albeit at a higher latitude in solar cycle 23 and only in the midst of the intermittent recurrent sequences.
Ob' River flood inundations from satellite observations: A relationship with winter snow parameters and river runoff
Authors: Papa F. , Prigent C. , Rossow W. B.
Published: September 2007

Using a multisatellite method, including passive microwave land surface emissivities, along with active microwave, visible and near infrared observations developed to estimate global inundated area, we examine the spatial and temporal variations of the 1993–2000 monthly inundation extents over a Boreal environment, the Ob River basin. Over the entire watershed, the mean extent of inundation during the snow‐free months is 2.6 × 105 km2, consistent with previous independent static or satellites‐derived estimates. The maximum in yearly inundation, showing propagation from south to north between April and June, exhibits strong seasonal and inter‐annual variations. The consistency of the inundation estimates is then analyzed at local or basin‐wide scale using different in situ or satellite‐derived snow and runoff parameters. The results show a strong relationship between the inundation extent and the snowmelt date, the snowpack depth at three in situ stations located in the southern part of the basin. Over the northern part, results show that flooding is more closely linked to the amount of water coming downstream from the southern part of the basin. A close systematic relationship is also found between the inundation extent and the local in situ runoff at six locations as well as with the altimeter‐derived discharge measured at the Ob estuary. This case study evaluation shows the potential of these data sets to provide consistent information about the seasonal and inter‐annual variations of inundation over a major Boreal river basin. These results also suggest new potential to improve the description of the snow‐inundation‐runoff relationship that are fundamental for climate and hydrological models.
Phonological Processing Skills of Adolescents With Residual Speech Sound Errors
Authors: Preston Jonathan L. , Edwards Mary Louise
Published: September 2007

Purpose

Research has shown that young children with speech sound disorders may have weaknesses in phonological processing. However, such skills have not been thoroughly examined in adolescents with residual speech sound errors. Therefore, this study compared the phonological processing abilities of adolescents with residual speech sound errors to those of normally speaking peers.

Method

Two nonword repetition tasks, multisyllabic word repetition, spoonerisms, phoneme reversals, and an elision task were used to compare the phonological processing skills of 10–14-year-olds with residual speech sound errors that include rhotic phonemes (RE,n= 13) to those of normally speaking (NS,n= 14) adolescents of similar age and receptive vocabulary abilities.

Results

The 2 groups were found to differ on 5 of the 6 phonological processing tasks. Discriminant analysis showed that 85% of the participants could be correctly classified into the RE and NS groups based solely on phonological processing skills.

Conclusion

The possible nature of the phonological processing impairment is discussed in the context of current theoretical understanding. It is recommended that when planning assessment and intervention for adolescents with residual speech sound errors, clinicians be cognizant of the fact that the adolescents may also have weaknesses in phonological processing.
Longitudinal Effects of Phonological Awareness Intervention on Morphological Awareness in Children With Speech Impairment
Authors: Kirk Cecilia , Gillon Gail T.
Published: September 2007

Purpose

This study examined reading performance and morphological awareness development in 2 groups of children with speech impairment who had received differing types of intervention during their preschool years.

Method

The children were aged between 7;6 and 9;5 (years;months) at the time of the study. Group 1 (
n
= 8) had received preschool intervention to facilitate phonological awareness and letter knowledge in addition to improving speech production. Group 2 (
n
= 9) had received preschool intervention that focused solely on improving speech intelligibility. A third group of children with typical development (Group 3,
n
= 24) also participated in the study. Two reading tests were administered, one that assessed word recognition and another that assessed nonword decoding. Two tests of morphological awareness were also administered, one that tested the spelling of morphologically complex words and another that tested the oral generation of the base form of derived words.

Results

Children with a history of speech impairment who had received phonological awareness intervention (Group 1) performed significantly better on nonword decoding and on the spelling of morphologically complex words than did children with a history of speech impairment whose intervention focused on speech only (Group 2). The typically developing children (Group 3) were not significantly different from Group 1 on the spelling of morphologically complex words, and like Group 1, they outperformed Group 2 on this measure. However, Group 3 did not perform significantly better than Group 2 on nonword decoding, and both of these groups performed significantly more poorly than Group 1 on this measure. There were no group differences in the ability to orally generate base words.

Conclusion

Children with a history of speech impairment who had received phonological awareness intervention and who became proficient readers demonstrated an ability to use morphological awareness in the spelling process that was similar to that of their peers without speech impairment. These findings highlight the potential long-term benefits associated with early phonological awareness intervention.
Complexities of Expressive Word Learning Over Time
Authors: McGregor Karla K. , Sheng Li , Ball Tracy
Published: September 2007

Purpose

The purpose of this study was to examine semantic and lexical aspects of word learning over time.

Method

Thirty-four 8-year-olds participated in vocabulary lessons for 2 weeks. Frequency of exposure and informativeness of semantic context were manipulated. A definition task assessed semantic learning and a naming task assessed lexical learning.

Results

Semantic and lexical knowledge accrued over time and were maintained after a 1-month interval. Higher frequency of exposure had an immediate effect on semantic learning and a more gradual effect on lexical learning. Frequency of exposure coupled with informative context promoted semantic learning.

Clinical Implications

Speech-language pathologists should be mindful of the richness of the learning context and the redundancy of massed and distributed exposures. Learning at the semantic and lexical levels can dissociate so both should be addressed.
Principals' Opinions on the Role of Speech-Language Pathologists Serving Students With Communication Disorders Involved in Violence
Authors: Ritzman Mitzi J. , Sanger Dixie
Published: September 2007

Purpose

The purpose of this study was to survey the opinions of principals concerning the role of speech-language pathologists (SLPs) serving students with communication disorders who have been involved in violence.

Method

A mixed methods design involving 678 questionnaires was mailed to elementary, middle, and high school principals in a Midwestern state. Descriptive statistics and qualitative analyses identifying themes from 1 open-ended question were conducted.

Results

A total of 423 (62.1%) questionnaires were received. Findings indicated that principals were aware of the important role of SLPs on multidisciplinary teams and in planning prevention programs. They agreed that SLP services positively impact students' social adjustment, academic performance, and behavior. Mean responses indicated uncertainty on 12 Likert-type items pertaining to SLPs' training in serving students who have been involved in violence. From 84 participants, 164 ideas emerged in seven themes: (a) intervention/service delivery, (b) definition of violence/relationship of violence to speech and language services, (c) role of SLP, (d) training/education, (e) frequency of violence/safety, and (g) impact of home environment.

Conclusion

Findings should be interpreted cautiously due to sample restrictions. Nevertheless, findings support that principals value SLPs' services. They also provide evidence for SLPs to continue to advocate for the services they perform, collaboration, and a range of service delivery models during intervention.
Exploration of Lexical–Semantic Factors Affecting Stress Production in Derived Words
Authors: Jarmulowicz Linda , Taran Valentina L.
Published: September 2007

Purpose

This study examined whether lexical frequency, semantic knowledge, or sentence context affect children’s production of primary stress in derived words with stress-changing suffixes (e.g.,-ity).

Method

Thirty children (Mage= 9;1 [years;months]) produced a limited set of high-frequency (HF) and low-frequency (LF) derived words formed with stress-changing suffixes (e.g.,-ity). Half of the children produced the derived words in a sentence context. The other half produced words in isolation. Semantic knowledge of the derived words was also assessed.

Results

Primary stress was produced more accurately in HF words than in LF words. HF words produced in a sentence context were more accurate than all LF words and HF words produced in isolation. Both knowing a word’s meaning and accurately producing stress was more likely for HF words than for LF words. A substantial minority of derived words (36%) was either known semantically or produced correctly, but not both.

Conclusion

Accurate morphophonological production may involve semantic and frequency factors, but those factors alone do not explain all of the results. This study isolates several important factors that may be useful when choosing derived word stimuli.
The Diagnostic and Predictive Validity of
The Renfrew Bus Story
Authors: Pankratz Mary E. , Plante Elena , Vance Rebecca , Insalaco Deborah M.
Published: September 2007

Purpose

Two studies are presented providing evidence indicating the diagnostic and predictive validity of the American version of
The Renfrew Bus Story
(J. Cowley & C. Glasgow, 1994).

Method

Thirty-two children with specific language impairment (SLI) and 32 children with typical language development participated in the first study to determine identification accuracy of
The Renfrew Bus Story
. A second study of 12 children with SLI participated in a 3-year longitudinal study that was used to gather evidence of the predictive validity of
The Renfrew Bus Story.

Results

The combined Information and Length scores of
The Renfrew Bus Story
yielded adequate (84%) sensitivity but weak (78%) specificity, making it an inappropriate tool for identifying children with language impairment or typical language development. Moderate to high correlations were found between
The Renfrew Bus Story
scores and nearly all scores from language tests administered 3 years later.

Implications

The evidence supports the use of
The Renfrew Bus Story
as an indicator of future language performance for children with SLI. However, its performance as a measure for identifying impairments during the preschool years is somewhat weaker due to overidentification of typically developing children, and in particular minority children, as having poor narrative skills.