bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ripple/dune to upper stage plane bed transition: Some observations from the ancient record
Authors: Chakraborty Chandan , Bose Pradip K. 
Published: February 2007

AbstractIn two Proterozoic sandstones, of the Indian shield cross‐stratification and cross‐lamination are observed to grade continuously into parallel‐laminations often bearing parting lineations. These are interpreted as having resulted from a gradual transition from ripple/dune to upper stage plane bed structures. During the transition the inclination of the cross‐strata diminishes and their shape changes from concave‐up to sigmoidal. The sigmoidal cross‐strata are characterized by well defined topsets, foresets and toesets and the topsets bear parting lineations. In the course of the transition sigmoidal cross‐strata may give way either to horizontal parallel‐lamination or inclined parallel‐lamination. In the former the toesets of the successive sigmoidal cross‐strata thicken and the thickness of the cross‐strata beyond the brink point (the junction between the topset and foreset) tends to become uniform until a plane‐bed state is reached and horizontal parallel‐laminations are formed. In the latter the topset of the successive sigmoidal cross‐strata increases in length at the expense of the foreset and toeset until the brink point ceases to exist so that only the topset laminations prevail and appear as inclined parallel‐laminations. These transitions presumably result from a gradual increase in flow intensity beyond the stability limits of ripples/dunes. The progressive morphological changes of the cross‐stratification over the transition are attributed to changing fallout patterns on the lee face of the bedforms in response to increasing flow intensity. Preservation of the records of such transitions suggests an abundant supply of sand grade sediments from suspension during the transition, shaping the sediment concentration profile over the bedforms and facilitating turbulence suppression. The variation in the pattern of transition from sigmoidal cross‐stratification to parallel‐lamination may be the result of different rates of sediment feed from the prevailing suspended sediment load in the two instances.
Loch lomond stadial glacier at Fan Hir, Mynydd Du (Brecon Beacons), South Wales: Critical evidence and palaeoclimatic implications
Authors: Shakesby Richard A. , Matthews John A. 
Published: February 2007

AbstractThe c. 1·2 km long, up to c. 25 m high ridge east of the almost north‐south aligned Fan Hir scarp, Mynydd Du, South Wales has been regarded as a remarkable protalus rampart formed in the Loch Lomond Stadial (c. 11–10000 years BP). New data are presented which indicate that it is a moraine. The main points supporting this glacigenic origin are: its curved plan form at the lower, southern end; its scale and the ample depth for snow to glacier ice transformation; the presence of subsidiary ridges interpreted as recessional moraines; the exceptional rate of rockwall retreat required if it were a protalus rampart; and, most importantly, the presence in the ridge of matrix‐supported abraded clasts, up to 20% of which are striated. Useful criteria for differentiating moraines and protalus ramparts are thereby proposed and a sound basis is provided for palaeoclimatic reconstruction. Palaeoclimatic inferences imply that the glacier owed its existence to the combined effect of a mean July temperature of c. 8·5°C and topographically enhanced accumulation, nearly half of which was from wind‐blown snow.
A rigid‐bodied Ediacaran Biota from Upper Cambrian strata in Co. Wexford, Eire
Authors: Crimes T. P. , Insole A. , Williams B. P. J. 
Published: February 2007

AbstractTwo typical representatives of the Ediacaran biota, Ediacaria booleyi n.sp. and Nimbia occlusa have been found in deep‐water turbidites within the Upper Cambrian Booley Bay Formation at Booley Bay in Co. Wexford, Eire. The examples of E. booleyi were transported over short distances by the turbidity currents and then impacted, in some instances at high angles, into the ocean floor muds where they formed moulds but, as their bodies decayed, these were filled by casting sand from the overlying turbidite. They preserved fine detail during transportation and impaction, thereby indicating the existence of a rigid body wall. The three‐dimensional nature of their preservation allows reconstruction, which shows that Ediacaria had a discoid form with prominent relief, particularly on its dorsal side, which was divided into three main concentric zones with thin radial features, more evident at the periphery. The ventral side had lower relief, with alternate areas of coarse and fine concentric markings and numerous fine radial lines, some also thicker at the periphery.Nimbia occlusa are disc‐like bodies of low relief and occur in profusion on one sole. Some show a circular outline indicating that they were preserved flat on the bedding plane, but others occur as semicircular reliefs oriented in the palaeocurrent direction. This indicates that they too were moved by the turbidity current, but their abundance and excellent preservation indicate that transport distances were short. There is no evidence in either genus for the coelenterate characteristics of a mouth and a two‐layered body wall enclosing a single cavity. This, and the evidence for a rigid outer wall, adds to recent doubt on the concept of the world‐wide Ediacaran fauna as dominated by soft‐bodied coelenterates.
Revision of the Carboniferous cystoporate bryozoan Fistulipora incrustans (Phillips, 1836), with remarks on the type species of Fistulipora M'Coy, 1849
Authors: Bancroft Adrian J. , Jackson Patrick N. Wyse 
Published: February 2007

AbstractThe type species of the Palaeozoic cystoporate bryozoan genusFistuliporaM'Coy, 1849 is redescribed.Fistulipora minorM'Coy, 1849 is the type species, and was the first species described under the genusFistulipora.Quantitative assessment of type and figured specimens ofCalamopora incrustansPhillips, 1836 andF. minorhas shown them to fall within the range of morphological variation exhibited by abundant comparative material collected at several horizons and they are referable to one morphologically variable taxon.F. minoris the junior subjective synonym ofC. incrustansand the form can be quoted asF. minorM'Coy, 1849 =C. incrustansPhillips, 1836 with a valid name ofF. incrustans(Phillips, 1836). However, this does not alter the name of the type species, which isF. minorM'Coy, 1849. The type specimen ofBerenicea megastomaM'Coy, 1844 has also been examined, and this form is also conspecific withF. minorM'Coy, 1849 =C. incrustansPhillips, 1836. Examination of the type specimen ofF. majorM'Coy (1849) has shown it to be referable to the tabulate coral genusChaetetes.A lectotype and paralectotypes are designated forF. minorand the status of the type specimens ofF. incrustansis clarified.
Petrographic evidence for diachronous metamorphism of the Skaiti Supergroup, Köli Nappe Complex, Arctic Scandinavian Caledonides
Authors: Westhead R. K. , Boyle A. P. 
Published: February 2007

AbstractThe Skaiti Supergroup is the uppermost major tectono‐stratigraphic unit of the Koli Nappe Complex, which comprises Precambrian to Lower Palaeozoic rocks immediately north of the Arctic Circle in Scandinavia. This complex was derived from within the lapetus Ocean and emplaced during the Scandian phase of the Caledonian Orogeny. Petrographic evidence along a hinterland to foreland traverse of the Skaiti Supergroup demonstrates that garnet, staurolite and kyanite porphyroblastesis was diachronous with respect to fabric development, becoming later towards the hinterland. The hinterland rocks experienced two discrete phases of heating, whereas the foreland rocks only experienced one. These observations are consistent with a recent tectonic model for diachronous burial and exhumation of the Koli Nappe Complex during emplacement.
Inverted metamorphic zonation in a basement‐derived nappe sequence, eastern margin of the Bohemian Massif
Authors: Štípská Pavla , Schulmann Karel 
Published: February 2007

AbstractInverted metamorphic zonation is developed in the basement‐derived nappe sequence at the eastern margin of the Bohemian Massif. Mineral reactions and geothermometry reveal an increase in temperature from 580–600°C to 650°C and an increase in pressure from 6 to 10 kbar from the bottom to the top of the nappe pile. Kinematic data and syntectonic crystallization of minerals indicate that the peak conditions were diachronously attained during a slow oblique underthrusting of the Brunovistulian basement. Geochronological data reveal about 20 Ma between granulite facies metamorphism of the upper plate and mineral cooling ages in lower plate, precluding perturbation of the geotherm by underthrusting. A model is suggested showing a progressive break‐up of the deepest part of the underthrust Brunovistulicum and subsequent migration of the intraplate to the base of the basement‐derived thrust sheet. The uplift of this unit led to its decompression while the rest of the basement was subject to continuous underthrusting. The inverted metamorphic zonation within a single unit is explained using a model of heterogeneous deformation of upward transported units and passive inversion of initially subhorizontal isograds.
Stabilities of negative correlations between blood oxygen level‐dependent signals associated with sensory and motor cortices
Authors: Tian Lixia , Jiang Tianzi , Liang Meng , Li Xiaobo , He Yong , Wang Kun , Cao Bingli , Jiang Tao 
Published: February 2007

AbstractCompared with positive correlations, negative correlations of blood oxygen level‐dependent (BOLD) signals (NCOBSs) have been much less studied. In most related studies, the NCOBSs have been accepted as stable without further consideration. To investigate the stabilities of NCOBSs associated with the auditory, motor, and visual cortices, we evaluated the negative correlation maps of each brain region under different “task‐backgrounds” within the same subject‐group, as well as within different subject‐groups during a conscious resting state. These “task‐backgrounds” refer to tasks not expected to activate the specific ROI under consideration and are in some sense analogous to “resting states.” We found that the negative correlation maps of the motor and visual cortices were quite variable between either different task‐backgrounds or different subject‐groups, whereas those of the auditory cortex exhibited some similarities. These results indicate that the NCOBSs associated with the motor and visual cortices were unstable both under task‐backgrounds and during the conscious resting state. The auditory cortex tended to have stable NCOBSs during these “resting states” (but scanner noise could make the auditory cortex “less resting”). This study highlights the importance of paying attention to the influence of the stabilities of NCOBSs in related studies and establishes the need for further studies on NCOBSs. Hum Brain Mapp 2007. © 2007 Wiley‐Liss, Inc.
Neural correlates of verbal feedback processing: An fMRI study employing overt speech
Authors: Christoffels Ingrid K. , Formisano Elia , Schiller Niels O. 
Published: February 2007

AbstractSpeakers use external auditory feedback to monitor their own speech. Feedback distortion has been found to increase activity in the superior temporal areas. Using fMRI, the present study investigates the neural correlates of processing verbal feedback without distortion. In a blocked design, the following conditions were presented: (1) overt picture‐naming, (2) overt picture‐naming while pink noise was presented to mask external feedback, (3) covert picture‐naming, (4) listening to the picture names (previously recorded from participants' own voices), and (5) listening to pink noise. The results show that auditory feedback processing involves a network of different areas related to general performance monitoring and speech‐motor control. These include the cingulate cortex and the bilateral insula, supplementary motor area, bilateral motor areas, cerebellum, thalamus and basal ganglia. Our findings suggest that the anterior cingulate cortex, which is often implicated in error‐processing and conflict‐monitoring, is also engaged in ongoing speech monitoring. Furthermore, in the superior temporal gyrus, we found a reduced response to speaking under normal feedback conditions. This finding is interpreted in the framework of a forward model according to which, during speech production, the sensory consequence of the speech‐motor act is predicted to attenuate the sensitivity of the auditory cortex. Hum Brain Mapp 2007. © 2007 Wiley‐Liss, Inc.
Prefrontal cortex activity is reduced in gambling and nongambling substance users during decision‐making
Authors: Tanabe Jody , Thompson Laetitia , Claus Eric , Dalwani Manish , Hutchison Kent , Banich Marie T. 
Published: February 2007

AbstractObjective: Poor decision‐making is a hallmark of addiction, whether to substances or activities. Performance on a widely used test of decision‐making, the Iowa Gambling Task (IGT), can discriminate controls from persons with ventral medial frontal lesions, substance‐dependence, and pathological gambling. Positron emission tomography (PET) studies indicate that substance‐dependent individuals show altered prefrontal activity on the task. Here we adapted the IGT to an fMRI setting to test the hypothesis that defects in ventral medial and prefrontal processing are associated with impaired decisions that involve risk but may differ depending on whether substance dependence is comorbid with gambling problems. Method: 18 controls, 14 substance‐dependent individuals (SD), and 16 SD with gambling problems (SDPG) underwent fMRI while performing a modified version of the IGT. Result: Group differences were observed in ventral medial frontal, right frontopolar, and superior frontal cortex during decision‐making. Controls showed the greatest activity, followed by SDPG, followed by SD. Conclusion: Our results support a hypothesis that defects in ventral medial frontal processing lead to impaired decisions that involve risk. Reductions in right prefrontal activity during decision‐making appear to be modulated by the presence of gambling problems and may reflect impaired working memory, stimulus reward valuation, or cue reactivity in substance‐dependent individuals. Hum Brain Mapp, 2007. © 2007 Wiley‐Liss, Inc.
Ventral visual cortex in humans: Cytoarchitectonic mapping of two extrastriate areas
Authors: Rottschy Claudia , Eickhoff Simon B. , Schleicher Axel , Mohlberg Hartmurt , Kujovic Milenko , Zilles Karl , Amunts Katrin 
Published: February 2007

AbstractThe extrastriate visual cortex forms a complex system enabling the analysis of visually presented objects. To gain deeper insight into the anatomical basis of this system, we cytoarchitectonically mapped the ventral occipital cortex lateral to BA 18/V2 in 10 human postmortem brains. The anatomical characterization of this part of the ventral stream was performed by examination of cell‐body‐stained histological sections using quantitative cytoarchitectonic analysis. First, the gray level index (GLI) was measured in the ventral occipital lobe. Cytoarchitectonic borders, i.e., significant changes in the cortical lamination pattern, were then identified using an observer‐independent algorithm based on multivariate analysis of GLI profiles. Two distinct cytoarchitectonic areas (hOC3v, hOC4v) were characterized in the ventral extrastriate cortex lateral to BA 18/V2. Area hOC3v was found in the collateral sulcus. hOC4v was located in this sulcus and also covered the fusiform gyrus in more occipital sections. Topographically, these areas thus seem to represent the anatomical substrates of functionally defined areas, VP/V3v and V4/V4v. Following histological analysis, the delineated cytoarchitectonic areas were transferred to 3D reconstructions of the respective postmortem brains, which in turn were spatially normalized to the Montreal Neurological Institute reference space. A probabilistic map was generated for each area which describes how many brains had a representation of this area in a particular voxel. These maps can now be used to identify the anatomical correlates of functional activations observed in neuroimaging experiments to enable a more informed investigation into the many open questions regarding the organization of the human visual cortex. Hum Brain Mapp 2007. © 2007 Wiley‐Liss, Inc.
Relationship between task‐related gamma oscillations and BOLD signal: New insights from combined fMRI and intracranial EEG
Authors: Lachaux Jean‐Philippe , Fonlupt Pierre , Kahane Philippe , Minotti Lorella , Hoffmann Dominique , Bertrand Olivier , Baciu Monica 
Published: February 2007

AbstractCognitive neuroscience relies on two sets of techniques to map the neural networks underlying cognition in humans: recordings of either regional metabolic changes (fMRI or PET) or fluctuations in the neural electromagnetic fields (EEG and MEG). Despite major advances in the last few years, an explicit linkage between the two is still missing and the neuroimaging community faces two complementary but unrelated sets of functional descriptions of the human brain. Such an explicit framework, linking the two approaches in potentially complex cognitive tasks and in a variety of brain regions would permit to combine them into fine spatio‐temporally‐grained human brain mapping procedures. We combined fMRI and intra‐cranial EEG recordings of the same epileptic patients during a semantic decision task and found a close spatial correspondence between regions of fMRI activations and recording sites showing EEG energy modulations in the gamma range (>40 Hz). Our findings further support previous findings that gamma band modulations co‐localize with BOLD variations and also indicate that fMRI may be used as a constraint to improve source reconstruction of gamma band EEG responses. Hum Brain Mapp, 2007. © 2007 Wiley‐Liss, Inc.
Integrated PET/CT system for staging and surveillance of skull base tumors
Authors: Gil Ziv , Even‐Sapir Einat , Margalit Nevo , Fliss Dan M. 
Published: February 2007

AbstractBackground.The utility of preoperative and postoperative whole body integrated positron emission tomography–computed tomography (PET‐CT) scanning for staging and follow‐up in patients with skull base tumors is undetermined.Methods.We prospectively evaluated PET‐CT findings in 47 patients using 57 scans. Most (35/47, 75%) had anterior skull base tumors and the majority (74%) had advanced‐stage (III–IV) disease.Results.The scans showed high sensitivity for detection of various types of malignant tumors and provided 39 items of additional information, changing the clinical staging and management of 11 patients (23%). Recurrence of primary tumors was detected in 8 patients, positive regional (neck) metastases in 3, and distant metastases in 3. The positive uptake was due to osteoradionecrosis in 2 other patients. The sensitivity of PET‐CT was 0.77 and the specificity was 0.81 (0.83 positive predictive value and 0.76 negative predictive value).Conclusions.PET‐CT provides accurate data on anatomy, tumor staging, and early disease recurrence in the skull base. © 2007 Wiley Periodicals, Inc. Head Neck 2007
Survival in patients with synovial sarcoma of the head and neck: Association with tumor location, size, and extension
Authors: Harb William J. , Luna Mario A. , Patel Shreyaskumar R. , Ballo Matthew T. , Roberts Dianna B. , Sturgis Erich M. 
Published: February 2007

AbstractBackground.The medical literature on synovial sarcoma (SS) of the head and neck region is limited. Thus, we determined whether clinical characteristics and treatment were associated with recurrence and survival rates in patients with SS of the head and neck.Methods.We retrospectively identified patients with a pathologic diagnosis of SS of the head and neck at our institution (a large tertiary comprehensive cancer center) and compared recurrence and survival rates by clinical characteristics and treatment.Results.Forty patients with SS of the head and neck were identified from 1945 to 2004 (first case in 1968), representing <5% of all head and neck sarcomas seen at our institution during this time period. Twenty‐three patients (58%) had the monophasic histologic subtype, 15 (38%) biphasic, and 2 unspecified. Most patients were male (73%), with a median age of 29years. SS tumors were most commonly located in the neck (60%); thus, the most common symptoms were a neck mass and neck pain. No patients reported a history of radiation exposure. Higher disease‐specific and overall survival rates were associated with upper aerodigestive tract location, tumors of ≤5 cm, and tumors did not extend into bone. Patients treated with surgery and adjuvant radiotherapy had higher survival and lower recurrence rates than did those treated with surgery alone or a combination of surgery, radiotherapy, and chemotherapy. This difference was not significant, and the subgroups were small, with substantial confounding by adverse prognostic factors.Conclusions.SS of the head and neck is extremely rare, and our results should be viewed with caution given the relatively small group size and treatment over a 36‐year period. Survival rates were associated with tumor location, size, and extension. Treatment of SS of the head and neck should be directed toward complete surgical resection. Given the known sensitivity of SS to contemporary chemotherapy, a multimodality approach should be considered in the perioperative setting, especially in high risk patients. © 2007 Wiley Periodicals, Inc. Head Neck 2007
Driving behaviors in patients with head and neck cancer during and after cancer treatment: A preliminary report
Authors: Yuen Hon K. , Gillespie Marion B. , Day Terry A. , Morgan Larissa , Burik Jerry K. 
Published: February 2007

AbstractBackground.The purpose of this study was to explore the driving behaviors of head and neck cancer patients during and after cancer therapy.Methods.Eighty‐three patients completed a questionnaire related to driving behaviors.Results.The survey revealed that 67.5% of respondents reported that they drove less or stopped driving during cancer therapy, and 26.5% continued to drive less or stopped driving after the completion of cancer therapy. Respondents typically reported greater concern about driving and relied more on other people for transportation during and after cancer therapy than before their diagnosis. Results indicated that the odds for self‐restricted driving after cancer therapy were higher for those who were more concerned about driving under challenging driving situations and perceived impaired cognitive function that affected their driving ability.Conclusions.These results suggest that perceived impairment resulting from cancer therapy has a significant impact on head and neck cancer patients' driving behaviors. © 2007 Wiley Periodicals, Inc. Head Neck 2007