bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chapter 52 The Playa Hermosa Formation, Playa Verde Basin, Uruguay
Authors: Pazos P. J. , Rapalini A. E. , Bettucci L. Sánchez , Tófalo O. R. 
Published: December 2011

Abstract

The Playa Hermosa Formation (Fm.) (Playa Verde Basin) is a volcano-sedimentary unit that crops out in the extreme south of the Dom Feliciano Belt in Uruguay. This formation has traditionally been interpreted as non-glacial in origin, but recently it has been suggested that the lower part at least may be glacially influenced. The stratigraphic position of the Playa Hermosa Fm. and its correlation with other Neoproterozoic units of Uruguay, Argentina and southern Brazil remains in dispute. An age of
c.
580 Ma is indicated by a hornblende
39
Ar/
40
Ar age on magmatism regarded as coeval with syn-sedimentary volcanism. Preliminary palaeomagnetic data suggest a primary remanence and a mean geomagnetic pole consistent with the proposed apparent polar wander path for the Río de La Plata craton. In combination, these data suggest mid-Ediacaran glacial sedimentation in low to intermediate latitudes on the Río de la Plata craton. However, this conclusion needs to be reinforced by more thorough studies of the age and origin of the Playa Hermosa Fm.
Chapter 53 Las Ventanas and San Carlos formations, Maldonado Group, Uruguay
Authors: Pecoits Ernesto , Gingras Murray K. , Konhauser Kurt O. 
Published: December 2011

Abstract

Together with the Playa Hermosa Formation (Fm.), the Las Ventanas and San Carlos formations constitute the Maldonado Group, which is better developed in the southeastern part of Uruguay and covers an area of
c.
200 km
2
. The total thickness of both units (i.e. Las Ventanas and San Carlos formations) reaches
c.
1500 m, and comprises mafic and acidic volcanic rocks, pyroclastic rocks, diamictite, sandstone, conglomerate and pelite. Structurally, the Maldonado Group is extensively deformed, although variably, throughout the region. Strike–slip faults, westward-verging detachment faults, and folds with axis sub-parallel to the strike–slip planes are common features. The presence of pumpellyite, prehnite, chlorite and epidote in mafic rocks indicates very low- to low-grade metamorphic conditions. The Las Ventanas Fm. is characterized by basal conglomerate, diamictite, sandstone and siltstone that pass upwards into fine-grained rhythmites (pelite), and is the thickest unit of the Maldonado Group (
c.
1250 m). The San Carlos Formation (
c.
250 m) comprises fine-grained conglomerate, sandstone and mudstone towards the top. Both units lie on an angular unconformity above Palaeo- and Neoproterozoic basement and are overlain unconformably by late Ediacaran–lowermost Cambrian units. Reliable palaeomagnetic data indicate that the Maldonado Group accumulated at high palaeolatitudes; however, the palaeogeographical evolution of the Río de la Plata Craton during the Neoproterozoic remains conjectural. Radiometric data from intrusive bodies and cross-cutting strike–slip faults place the minimum age of the group at
c.
565 Ma, whereas basement volcanic rocks dated at 590
±
2 Ma interbedded with meta-sandstones hosting detrital zircons
c.
600 million years old provide the best constraint on the maximum age of deposition. Given the absence of carbonate rocks, no chemostratigraphic studies (e.g. C, O, Sr) are available.

The Las Ventanas and San Carlos formations are largely interpreted as units within a thick glacially influenced fan-delta sedimentary system formed during the early Ediacaran in a strike–slip basin. Based on stratigraphic and sedimentological characteristics it has been suggested that this succession, containing glacially influenced diamictite and dropstones, records a glacial period that occurred sometime between
c.
570 and 590 million years ago. Ongoing research is focused on establishing the precise age of deposition of the Maldonado Group and on reconstructing the tectonic evolution of the basin. Further palaeomagnetic studies will be especially useful for determining the palaeogeography of the Río de la Plata Craton during the Ediacaran and establishing its relationships with neighbouring strata hosting similar successions.
Chapter 62 The Port Askaig Formation, Dalradian Supergroup, Scotland
Authors: Arnaud Emmanuelle , Fairchild Ian J. 
Published: December 2011

Abstract

The Port Askaig Formation (Fm.) is a thick glaciogenic succession within the Dalradian Supergroup that consists of over 700 m of variably dolomitic diamictite, conglomerate, sandstone mudstone and minor dolomite, and is bounded by mixed siliciclastic–carbonate successions of the Islay (Lossit) and Bonahaven formations. These strata are exposed in the metamorphic Caledonides of Scotland, although excellent preservation of sedimentary structures can be found at several sites. An extensional setting for this succession has been proposed based on stratigraphic and structural arguments. The available chemostratigraphic data include the Chemical Index of Alteration, δ
13
C and Sr-isotope values. Palaeomagnetic analyses have been shown to be subject to post-depositional Caledonian overprinting. There is also continued debate over the regional palaeogeographical reconstructions of the Scottish promontory for this time period. The succession is chronologically poorly constrained with U–Pb analyses of stratigraphically much higher or lower deposits. The thick succession is thought to record glacially influenced marine sedimentation and reworking of unstable sediments in a tectonically active setting with evidence of ice-margin fluctuations. Alternative palaeoenvironmental interpretations that focus on glacial terrestrial processes and emphasize climatic influence instead of tectonic activity have also been proposed. The overlying carbonate is a lithologically diverse coastal complex and so does not fit the Neoproterozoic norm. Research has to date focused on the stratigraphic and sedimentological aspects of this succession, as well as some of the broader palaeogeographical and structural features of the Dalradian basin. Future efforts should focus on the chronological, structural and palaeogeographical constraints of this succession.
Chapter 64 Neoproterozoic glacial deposits of Tasmania
Authors: Calver Clive R. 
Published: December 2011

Abstract

In Tasmania, Neoproterozoic glaciogenic deposits were laid down in one or more epicratonic basins, probably situated at the eastern margin of the Australian–Antarctic craton. Rifting and volcanism took place in the late Cryogenian to early Ediacaran. On King Island, north of Tasmania, the Cottons Breccia consists of 50–200 m of diamictite, conglomerate and sandstone. Limestone and dolostone clasts are abundant in the diamictite, although carbonate is unknown in the underlying successions. The Cottons Breccia is overlain by 10 m of laminated dolostone and limestone with a negative, upward-decreasing δ
13
C profile. Rift volcanics and shallow intrusives higher in the sequence are dated at
c.
575 Ma. In NW Tasmania, two diamictite units are found in the Togari Group. The Julius River Member, 200 m thick, contains dominantly dolostone clasts and overlies a shallow-marine dolostone unit with vase-shaped microfossils and C-isotopes consistent with a mid-Cryogenian age. Some clasts in the Julius River Member contain a stromatolite (
Baicalia
cf.
B. burra
) very similar to a form that is abundant in the middle part of the Burra Group, Adelaide rift basin. The Julius River Member is immediately overlain by black shale and impure carbonate dated by Re–Os at 641±5 Ma. The younger diamictite in the Togari Group is the Croles Hill Diamictite, 70 m thick, with predominantly volcanic clasts, underlain by a shale and mafic-volcaniclastic succession and overlain by thin mudstone followed by thick rift tholeiites. At one locality this diamictite is underlain by a rhyodacite flow dated at 582±4 Ma. In southern Tasmania, diamictites are found in the Wedge River Beds and in the Cotcase Creek Formation (Fm.) (Weld River Group). Laminated siltstone with dropstones is associated with the diamictites in the Cotcase Creek Fm. The southern Tasmanian deposits are poorly constrained in age.

Chronometric and other evidence suggests correlation of the Julius River Member, Cottons Breccia and Croles Hill Diamictite with the Sturt, Elatina and Gaskiers glacial phases, respectively. However, a glacial origin for the Julius River Member and Croles Hill Diamictite remains uncertain.
Chapter 68 Billy Springs glaciation, South Australia
Authors: Jenkins Richard J. F. 
Published: December 2011

Abstract
An interval several hundred metres thick in the lower part of the late Ediacaran Billy Springs Formation (Fm.) of the NE Flinders Ranges, South Australia, includes both diamictic levels, ‘dropstones’ and isolated ‘stone-clusters’ in a thin-bedded, silty or fine sandy matrix, which is commonly laminated. Slumping at a variety of scales is prevalent, but extensive panels of ‘right-way-up’, moderately dipping beds host dropstones, which disturbed the laminae. It is difficult to explain laminated sediments peppered with dropstones other than by ice-rafting, and the stone-clusters comply with sinking pieces of ice loaded with debris. Although common reworking occurred in channels, larger erratics in this material are out of hydrodynamic equilibrium. Deposition occurred offshore on an unstable slope.

Isotopic δ
13
C
carb
measurements show a strong negative excursion through the preceding Wonoka Fm., and several further similar negative excursions in the Billy Springs Fm. This record shows similarities to that of Ediacaran carbonates on the Yangtze platform, south China. Compilation based on a survey of palaeomagnetic data for Gondwana continents, Baltica and Laurasia permits a possible palaeogeography indicating a relatively high palaeolatitude at the time of deposition. Indications of age are imprecise but may be comparable with, or younger(?) than the
c.
580 Ma Gaskiers Fm. of Newfoundland.
Chapter 7 Neoproterozoic glacial palaeolatitudes: a global update
Authors: Evans D. A. D. , Raub T. D. 
Published: December 2011

Abstract
New stratigraphic, geochronological and palaeomagnetic constraints allow updates to be made to a synthesis of Neoproterozoic glacial palaeolatitudes, including modifications to some reliability estimates. The overall pattern of a Neoproterozoic climatic paradox persists: there is an abundance of tropical palaeolatitudes and near to complete absence of glaciogenic deposits demonstrably laid down between latitudes of 60° and 90°. In addition to 12 units with palaeolatitude estimates that are somewhat reliable, estimates with moderate to high reliability now include Konnarock (less than 10° from the palaeo-equator), Elatina, Rapitan, Mechum River, Grand Conglomerat (10–20°), Upper Tindir, Puga (20–30°), Nantuo, Gaskiers (30–40°) and Walsh (40–50°). Among these, Elatina, Upper Tindir and Nantuo are considered to have the highest reliability, all with estimates of low to moderate palaeolatitude. The Elatina result stems from sedimentary rocks with quantitative correction of inclination-shallowing effects, and the Upper Tindir result stems from data collected from igneous rocks that are precisely coeval with the glacial deposits. Despite continuing debate on the global character of Neoproterozoic ice ages, their pan-glacial extent (ice extending to low latitude in a low-obliquity world) is well demonstrated.
Stigmatization of people with mental illness among inhabitants of a rural community in northern Nigeria
Authors: Audu Ishaq A. , Idris Suleiman H. , Olisah Victor O. , Sheikh Taiwo L. 
Published: December 2011

Background: Despite the fact that mental illness is a common problem in society, people’s perception of the mentally ill and community attitude towards them is still rather poor, making their rehabilitation and reintegration into society an uphill task. Aims: To examine the stigmatization of people with mental illness within a rural community and identify the socio-demographic variables involved. Method: A cross-sectional descriptive study using a multi-stage random sampling technique to obtain data through an interviewer-administered questionnaire to 325 adult inhabitants of a rural community in Nigeria. Results: The results showed widespread ignorance about causation, mode of transmission and remedies available for mental illness, with only 0.9% of respondents attributing mental illness to brain disease. The others attributed it to spiritual attack, punishment for evil doing and illicit psychoactive substance use, among other things. Negative views about the mentally ill were also widely expressed resulting in discriminatory practices. Conclusion: Stigmatization of people with mental illness is still rampant in our community. There is a need for adequate public education about the causes and mode of transmission of mental illness and the treatment options available in the community.
Attachment and hikikomori: A psychosocial developmental model
Authors: Krieg Alexander , Dickie Jane R. 
Published: December 2011

Background: Hikikomori (acute social withdrawal) is a social issue in Japan that affects both the society and the lives of the individual sufferers. Aims: This study aims to connect attachment theory and hikikomori by using a culturally sensitive psychosocial developmental model that outlines the various stages of attachment throughout the developmental years. Method: Twenty–four hikikomori sufferers and 60 comparison group participants were given questionnaires assessing parent and peer relationships, temperament and school experiences. Results: We found the hikikomori participants had a higher incidence of ambivalent attachment, reported more parental and peer rejection and bullying, and expressed greater temperamental shyness. Path analysis supported our developmental model. We found that shy temperament and parental rejection predicted ambivalent attachment, which when coupled with peer rejection predicted hikikomori. Our model implies that treatment and prevention may require attention to attachment insecurities in early childhood, peer rejection in middle childhood and/or early adolescence. Conclusion: We believe it is helpful in understanding hikikomori to first understand how the attachment system balances security with exploration and the anxiety associated with novelty and challenge. Finally, we examine implications of the model for intervention, treatment and future research.
Former Male Elite Athletes Have a Higher Prevalence of Osteoarthritis and Arthroplasty in the Hip and Knee Than Expected
Authors: Tveit Magnus , Rosengren Björn E. , Nilsson Jan-Åke , Karlsson Magnus K. 
Published: December 2011

Background: Intense exercise has been reported as one risk factor for hip and knee osteoarthritis (OA). Purpose: This study aimed to evaluate (1) whether this is true for both former impact and nonimpact athletes, (2) if the risk of a hip or knee arthroplasty due to OA is higher than expected, and (3) if joint deterioration is associated with knee injuries. Study Design: Cohort study; Level of evidence, 3. Methods: The prevalence of OA and arthroplasty in the hip and knee were registered in 709 former male elite athletes with a median age of 70 years (range, 50-93 years), retired from sports for a median 35 years (range, 1-63 years), and compared with 1368 matched controls. Odds ratios (ORs) are presented as means with 95% confidence intervals (95% CIs). Results: The risk of hip or knee OA was higher in former athletes (OR, 1.9; 95% CI, 1.5-2.3), as was arthroplasty based on OA in either of these joints (OR, 2.2; 95% CI, 1.6-3.1). The risk of hip OA was doubled (OR, 2.0; 95% CI, 1.5-2.8) and hip arthroplasty was 2.5 times higher (OR, 2.5; 95% CI, 1.6-3.7) in former athletes than in controls, predominantly driven by a higher risk in former impact athletes. Also, the risk of knee OA was higher (OR, 1.6; 95% CI, 1.3-2.1), as was knee arthroplasty (OR, 1.6; 95% CI, 0.9-2.7), driven by a higher risk in both former impact and nonimpact athletes. Knee OA in impact athletes was associated with knee injury. Conclusion: Hip and knee OA and hip and knee arthroplasty are more commonly found in former male elite athletes than expected. A previous knee injury is associated with knee OA in former impact athletes but not in nonimpact athletes.
Dielectric relaxation and rheological properties of single-walled carbon nanotubes reinforced poly(3-octylthiophene-2,5-diyl)
Authors: Abu-Abdeen M , Ayesh Ayman S , Aljaafari AA 
Published: December 2011

Polymer nanocomposites consisting of single-walled carbon nanotubes (SWCNTs) and poly(3-octylthiophene-2,5-diyl) (P3OT) were prepared at different SWCNT loadings to investigate the influence of SWCNT content on the structure, dielectric and rheological properties of P3OT host. The dielectric parameters and dielectric relaxation behavior were investigated as a function of SWCNT loadings and frequency. Dielectric results reveal that SWCNTs enhance the polar character of P3OT host, shift the peak maximum of loss tangent toward higher frequency values and increase the alternating current conductivity especially above the percolation threshold point. Besides, the rheological properties of SWCNT-P3OT composites were also investigated to realize the effect of SWCNT content on the complex viscosity, storage and loss moduli at different frequency values. The obtained results reveal that nanocomposites become electrically percolated at 0.44 wt% SWCNTs, while the rheological percolation threshold was found at 0.5 wt%. Additionally, this study showed that the relaxation behavior in SWCNT-P3OT composites is mainly due to the viscoelastic relaxation process. Moreover, at high level of SWCNT loadings, the nanotubes became more interconnected to form network like structures in the P3OT host. Finally, results obtained from structure–property analysis reveal that the addition of SWCNTs to P3OT host reduced the vibrational freedom of the polymer chains as a consequence of the intercalation of the polymer matrix into the nanotubes.
Multiscale analysis of stamp forming of a woven composite
Authors: Garnich Mark R , Klymyshyn Nicholas A 
Published: December 2011

The stamp forming of a woven composite with thermoplastic matrix was investigated in this study. A mesoscale finite element model of a unit cell of a 2 × 2 twill weave of pre-impregnated tows was used to estimate the effective in-plane shear properties for modeling forming processes and predicting formability. In-plane shear stiffness was shown to be a controlling factor in the formability of unconsolidated textile sheets. The stamp forming of a cone-shaped part was modeled for comparison with the experiments. Results show that the simplified process modeling scheme has the potential to predict issues with wrinkling during die closure. Furthermore, the present work suggests that complex representations of the relatively small fiber direction strains may be unwarranted for this type of process modeling.
Trisomy 12 and elevated GLI1 and PTCH1 transcript levels are biomarkers for Hedgehog-inhibitor responsiveness in CLL
Authors: Decker Sarah , Zirlik Katja , Djebatchie Lauritte , Hartmann David , Ihorst Gabriele , Schmitt-Graeff Annette , Herchenbach Dieter , Jumaa Hassan , Warmuth Markus , Veelken Hendrik , Dierks Christine 
Published: December 2011

AbstractHedgehog (HH) signaling is activated in various lymphoid malignancies, but conflicting results exist about its role in chronic lymphocytic leukemia (CLL). Here, we demonstrate that the expression of essential HH pathway components like GLI1, PTCH1, and the HH ligands is highly diverse in CLL. A subset of 36.7% of 60 tested CLL samples responded to all 3 SMOOTHENED (SMO) inhibitors, whereas 40% were completely resistant. Responsiveness correlated with elevated GLI1 and PTCH1 transcript levels and the presence of trisomy 12, whereas no other karyotype correlated with responsiveness. All trisomy 12 CLLs displayed constitutive HH pathway activation driven by autocrine DESERT HH (DHH) ligand secretion, which could be blocked by the HH-blocking Ab 5E1. Cocultures with DHH-expressing BM stromal cells reduced sensitivity of CLLs to SMO-inhibitor treatment by activation of noncanonical ERK phosphorylation directly downstream of the PTCH1 receptor without involvement of SMO and could be overcome by the HH-blocking Ab 5E1 or a combination of SMO and ERK inhibitors. Our results demonstrate that the HH-signaling pathway is an interesting therapeutic target for a subset of patients with CLL, characterized by high GLI1 and PTCH1 transcript levels, and all patients with trisomy 12 and indicate HH-blocking Abs to be favorable over SMO inhibitors in overcoming stroma-mediated protective effects.
Nocturnal hypoxaemia and hypercapnia in children with neuromuscular disorders
Authors: Bersanini Chiara , Khirani Sonia , Ramirez Adriana , Lofaso Frédéric , Aubertin Guillaume , Beydon Nicole , Mayer Michèle , Maincent Kim , Boulé Michèle , Fauroux Brigitte 
Published: December 2011

The aim of the study was to identify daytime predictors of nocturnal gas exchange anomalies in children with neuromuscular disease (NMD) and normal daytime gas exchange.Lung function tests, respiratory muscle evaluation and nocturnal gas exchange were obtained as part of routine evaluation.We included 52 consecutive children with Duchenne muscular dystrophy (n=20), spinal muscular atrophy (n=10) and other NMD (n=22). 20 patients had nocturnal hypoxaemia, defined as minimal arterial oxygen saturation measured by pulse oximetry (Sp,O2) <90% for ≥2% of night time, and 22 had nocturnal hypercapnia, defined as maximal transcutaneous carbon dioxide tension (Ptc,CO2) >50 mmHg for ≥2% of night time. Forced vital capacity and helium functional residual capacity correlated with minimal nocturnalSp,O2(p=0.009 and p=0.01, respectively). Daytime pH correlated negatively with maximal nocturnalPtc,CO2(p=0.005) and daytime arterial carbon dioxide tension (Pa,CO2) correlated with the percentage of time with aPtc,CO2>50 mmHg (p=0.02). Sniff nasal inspiratory pressure correlated with minimal nocturnalSp,O2(p=0.02). DaytimePa,CO2was a weak predictor of nocturnal hypercapnia (sensitivity 80%; specificity 57%).Daytime lung function and respiratory muscle parameters correlate poorly with nocturnal hypoxaemia and hypercapnia in children with NMD and normal daytime gas exchange, which necessitates more systematic sleep studies in these children.
Effectiveness of exercise training in patients with COPD: the role of muscle fatigue
Authors: Burtin Chris , Saey Didier , Saglam Melda , Langer Daniel , Gosselink Rik , Janssens Wim , Decramer Marc , Maltais François , Troosters Thierry 
Published: December 2011

The improvement in exercise performance in response to exercise training varies greatly from one patient with chronic obstructive pulmonary disease to another. It is possible that in a portion of patients the muscle stimulus applied during exercise training is insufficient to elicit training effects. We investigated whether patients presenting quadriceps contractile fatigue after training have more favourable effects of a rehabilitation programme.46 patients followed a 3-month high-intensity exercise training programme. Exercise capacity, quadriceps force and quality of life were measured before and after the programme. Exercise training-induced quadriceps contractile fatigue was assessed after 1 month of rehabilitation with magnetic stimulation. A fall in quadriceps force of ≥15%, 15 min after training was considered as significant fatigue.29 (63%) out of 46 patients developed significant fatigue. Patients with fatigue had a higher increase in 6-min walk distance (median (interquartile range) 57 (47–103) mversus17 (-7–46) m; p=0.0023) and Chronic Respiratory Disease Questionnaire score (mean±sd22±12 pointsversus14±12 points; p=0.028) after the training programme compared with patients without fatigue. Improvements in quadriceps force and maximal exercise capacity were similar in both subgroups.Patients who develop quadriceps contractile fatigue during exercise training show greater training effects in terms of functional exercise capacity and health-related quality of life.