Change of the condyle-position in maximum intercuspidation during digital, clinical occlusal analysis

Digital analysis of the occlusal contacts can be performed with the T-scan device (T Scan III, TekScan, Boston, USA). However, the thickness of the interocclusal T-scan sheet (100 μm) may lead to a displacement of the mandible. Thus, the aim of this study was to investigate the impact of the T-scan sheet on the position of the mandibular condyles in maximum intercuspidation. Twenty dentate subjects with healthy jaw function were enrolled in the study. An ultrasonic axiography device was used to measure the position of the condyles. Ten 3D condyle positions in maximum intercuspidation of the teeth were recorded: first the reference position without the sheet, then 3 times without the sheet, 3 times with the sheet, and finally again 3 times without the sheet. There was a statistically significant difference (Wilcoxon matched pairs test) between the condyle positions with and without the interocclusally positioned T-scan sheet (P < 0.0005). The T-scan device lead to a displacement of the condyles of about 1 mm mainly in ventral direction (P = 0.005). Thus, occlusal analysis is not performed in physiological, maximum intercuspidation. This has to be considered when interpreting the measured contact points.

Glacier response to the change in atmospheric circulation in the eastern Mediterranean during the Last Glacial Maximum

In this study, we document glacial deposits and reconstruct the glacial history in the Karagöl valley system in the eastern Uludağ in northwestern Turkey based on 42 cosmogenic 10Be exposure ages from boulders and bedrock. Our results suggest the Last Glacial Maximum (LGM) advance prior to 20.4 ± 1.2 ka and at least three re-advances until 18.6 ± 1.2 ka during the global LGM within Marine Isotope Stage-2. In addition, two older advances of unknown age are geomorphologically well constrained, but not dated due to the absence of suitable boulders. Glaciers advanced again two times during the Lateglacial. The older is exposure dated to not later than 15.9 ± 1.1 ka and the younger is attributed to the Younger Dryas (YD) based on field evidence. The timing of the glaciations in the Karagöl valley correlates well with documented archives in the Anatolian and Mediterranean mountains and the Alps. These glacier fluctuations may be explained by the change in the atmospheric circulation pattern during the different phases of North Atlantic Oscillation (NAO) winter indices.

Transient simulations of the carbon and nitrogen dynamics in northern peatlands: from the Last Glacial Maximum to the 21st century

The development of northern high-latitude peatlands played an important role in the carbon (C) balance of the land biosphere since the Last Glacial Maximum (LGM). At present, carbon storage in northern peatlands is substantial and estimated to be 500 ± 100 Pg C (1 Pg C = 1015 g C). Here, we develop and apply a peatland module embedded in a dynamic global vegetation and land surface process model (LPX-Bern 1.0). The peatland module features a dynamic nitrogen cycle, a dynamic C transfer between peatland acrotelm (upper oxic layer) and catotelm (deep anoxic layer), hydrology- and temperature-dependent respiration rates, and peatland specific plant functional types. Nitrogen limitation down-regulates average modern net primary productivity over peatlands by about half. Decadal acrotelm-to-catotelm C fluxes vary between −20 and +50 g C m−2 yr−1 over the Holocene. Key model parameters are calibrated with reconstructed peat accumulation rates from peat-core data. The model reproduces the major features of the peat core data and of the observation-based modern circumpolar soil carbon distribution. Results from a set of simulations for possible evolutions of northern peat development and areal extent show that soil C stocks in modern peatlands increased by 365–550 Pg C since the LGM, of which 175–272 Pg C accumulated between 11 and 5 kyr BP. Furthermore, our simulations suggest a persistent C sequestration rate of 35–50 Pg C per 1000 yr in present-day peatlands under current climate conditions, and that this C sink could either sustain or turn towards a source by 2100 AD depending on climate trajectories as projected for different representative greenhouse gas concentration pathways.

A reconstruction of atmospheric carbon dioxide and its stable carbon isotopic composition from the penultimate glacial maximum to the last glacial inception

The reconstruction of the stable carbon isotope evolution in atmospheric CO2 (δ13Catm), as archived in Antarctic ice cores, bears the potential to disentangle the contributions of the different carbon cycle fluxes causing past CO2 variations. Here we present a new record of δ13Catm before, during and after the Marine Isotope Stage 5.5 (155 000 to 105 000 yr BP). The dataset is archived on the data repository PANGEA® (www.pangea.de) under 10.1594/PANGAEA.817041. The record was derived with a well established sublimation method using ice from the EPICA Dome C (EDC) and the Talos Dome ice cores in East Antarctica. We find a 0.4‰ shift to heavier values between the mean δ13Catm level in the Penultimate (~ 140 000 yr BP) and Last Glacial Maximum (~ 22 000 yr BP), which can be explained by either (i) changes in the isotopic composition or (ii) intensity of the carbon input fluxes to the combined ocean/atmosphere carbon reservoir or (iii) by long-term peat buildup. Our isotopic data suggest that the carbon cycle evolution along Termination II and the subsequent interglacial was controlled by essentially the same processes as during the last 24 000 yr, but with different phasing and magnitudes. Furthermore, a 5000 yr lag in the CO2 decline relative to EDC temperatures is confirmed during the glacial inception at the end of MIS5.5 (120 000 yr BP). Based on our isotopic data this lag can be explained by terrestrial carbon release and carbonate compensation.

Terrestrial and submarine evidence for the extent and timing of the Last Glacial Maximum and the onset of deglaciation on the maritime-Antarctic and sub-Antarctic islands

This paper is the maritime and sub–Antarctic contribution to the Scientific Committee for Antarctic Research (SCAR) Past Antarctic Ice Sheet Dynamics (PAIS) community Antarctic Ice Sheet reconstruction. The overarching aim for all sectors of Antarctica was to reconstruct the Last Glacial Maximum (LGM) ice sheet extent and thickness, and map the subsequent deglaciation in a series of 5000 year time slices. However, our review of the literature found surprisingly few high quality chronological constraints on changing glacier extents on these timescales in the maritime and sub–Antarctic sector. Therefore, in this paper we focus on an assessment of the terrestrial and offshore evidence for the LGM ice extent, establishing minimum ages for the onset of deglaciation, and separating evidence of deglaciation from LGM limits from those associated with later Holocene glacier fluctuations. Evidence included geomorphological descriptions of glacial landscapes, radiocarbon dated basal peat and lake sediment deposits, cosmogenic isotope ages of glacial features and molecular biological data. We propose a classification of the glacial history of the maritime and sub–Antarctic islands based on this assembled evidence. These include: (Type I) islands which accumulated little or no LGM ice; (Type II) islands with a limited LGM ice extent but evidence of extensive earlier continental shelf glaciations; (Type III) seamounts and volcanoes unlikely to have accumulated significant LGM ice cover; (Type IV) islands on shallow shelves with both terrestrial and submarine evidence of LGM (and/or earlier) ice expansion; (Type V) Islands north of the Antarctic Polar Front with terrestrial evidence of LGM ice expansion; and (Type VI) islands with no data. Finally, we review the climatological and geomorphological settings that separate the glaciological history of the islands within this classification scheme.

A community-based geological reconstruction of Antarctic Ice Sheet deglaciation since the Last Glacial Maximum

A robust understanding of Antarctic Ice Sheet deglacial history since the Last Glacial Maximum is important in order to constrain ice sheet and glacial-isostatic adjustment models, and to explore the forcing mechanisms responsible for ice sheet retreat. Such understanding can be derived from a broad range of geological and glaciological datasets and recent decades have seen an upsurge in such data gathering around the continent and Sub-Antarctic islands. Here, we report a new synthesis of those datasets, based on an accompanying series of reviews of the geological data, organised by sector. We present a series of timeslice maps for 20 ka, 15 ka, 10 ka and 5 ka, including grounding line position and ice sheet thickness changes, along with a clear assessment of levels of confidence. The reconstruction shows that the Antarctic Ice sheet did not everywhere reach the continental shelf edge at its maximum, that initial retreat was asynchronous, and that the spatial pattern of deglaciation was highly variable, particularly on the inner shelf. The deglacial reconstruction is consistent with a moderate overall excess ice volume and with a relatively small Antarctic contribution to meltwater pulse 1a. We discuss key areas of uncertainty both around the continent and by time interval, and we highlight potential priorities for future work. The synthesis is intended to be a resource for the modelling and glacial geological community.

Glacier advances in northeastern Turkey before and during the global Last Glacial Maximum

Abstract Our study in the Başyayla Valley in northeastern Anatolia showed evidence of four glacier advances that built terminal and lateral moraines. Surface exposure dating of boulders on these moraines showed that the Maximum Ice Extent (MIE) was asynchronous with the global Last Glacial Maximum (LGM; 22.1 ± 4.3 thousand years; ka). The local {MIE} took place at least 57.0 ± 3.5 ka ago. The extent of the Başyayla Glacier during this advance is not known exactly because the boulders are only preserved on a lateral moraine. The next advance was prior to 41.5 ± 2.5 ka, and it descended down the valley to approximately 2320 m above sea level (m a.s.l.), with a glacier length of 5.3 km. During the early global LGM, the Başyayla Glacier extended for a distance of 4.9 km down to approx. 2430 m a.s.l. The last recorded advance occurred during the global LGM. This extension was 0.7 km smaller than the local {MIE} and its terminus reached 2490 m a.s.l. only. The exposure ages of boulders in a retreat position at an altitude of approx. 3045 m a.s.l. indicate that the valley has remained ice-free since the Lateglacial period. Therefore, the Lateglacial extent was limited to the cirque system in the uppermost part of the catchment. Furthermore, Holocene glacier oscillations seem to be either absent or restricted to solifluction in the whole catchment and to rock glacier movements in the southern tributary of the Başyayla Valley system.

Timing of retreat of the Reuss Glacier (Switzerland) at the end of the Last Glacial Maximum

We used cosmogenic 10Be and 36Cl to establish the timing of the onset of deglaciation after the Last Glacial Maximum of the Reuss Glacier, one of the piedmont lobes of the Alpine ice cap that reached the northern Alpine foreland in Switzerland. In this study, we sampled erratic boulders both at the frontal position in the foreland (Lenzburg and Wohlen, canton Aargau) and at the lateral Alpine border position (Seeboden moraine, Rigi, canton Schwyz). The minimum age for the beginning of retreat is 22.2 ± 1.0 ka at the frontal (terminal) position and 20.4 ± 1.0 ka at the lateral position. These ages are directly comparable with exposure ages from the other piedmont lobes in the northern Alpine foreland. Our data from the mountain called Rigi, do not support the hypothesis that boulders located external to the Seeboden moraine were deposited prior to the last glacial cycle. We present a first exposure age from an erratic boulder in a retreat position in the Alpine foreland. The Reuss Glacier was approximately 12 km behind the maximal extent no later than at 18.6 ± 0.9 ka.

Modern solar maximum forced late twentieth century Greenland cooling

The abrupt Northern Hemispheric warming at the end of the twentieth century has been attributed to an enhanced greenhouse effect. Yet Greenland and surrounding subpolar North Atlantic remained anomalously cold in 1970s to early 1990s. Here we reconstructed robust Greenland temperature records (North Greenland Ice Core Project and Greenland Ice Sheet Project 2) over the past 2100 years using argon and nitrogen isotopes in air trapped within ice cores and show that this cold anomaly was part of a recursive pattern of antiphase Greenland temperature responses to solar variability with a possible multidecadal lag. We hypothesize that high solar activity during the modern solar maximum (approximately 1950s–1980s) resulted in a cooling over Greenland and surrounding subpolar North Atlantic through the slowdown of Atlantic Meridional Overturning Circulation with atmospheric feedback processes.

Positron emission mammography in the diagnosis of breast cancer. Is maximum PEM uptake value a valuable threshold for malignant breast cancer detection?

AIM To evaluate the diagnostic value (sensitivity, specificity) of positron emission mammography (PEM) in a single site non-interventional study using the maximum PEM uptake value (PUVmax). PATIENTS, METHODS In a singlesite, non-interventional study, 108 patients (107 women, 1 man) with a total of 151 suspected lesions were scanned with a PEM Flex Solo II (Naviscan) at 90 min p.i. with 3.5 MBq 18F-FDG per kg of body weight. In this ROI(region of interest)-based analysis, maximum PEM uptake value (PUV) was determined in lesions, tumours (PUVmaxtumour), benign lesions (PUVmaxnormal breast) and also in healthy tissues on the contralateral side (PUVmaxcontralateral breast). These values were compared and contrasted. In addition, the ratios of PUVmaxtumour / PUVmaxcontralateral breast and PUVmaxnormal breast / PUVmaxcontralateral breast were compared. The image data were interpreted independently by two experienced nuclear medicine physicians and compared with histology in cases of suspected carcinoma. RESULTS Based on a criteria of PUV>1.9, 31 out of 151 lesions in the patient cohort were found to be malignant (21%). A mean PUVmaxtumour of 3.78 ± 2.47 was identified in malignant tumours, while a mean PUVmaxnormal breast of 1.17 ± 0.37 was reported in the glandular tissue of the healthy breast, with the difference being statistically significant (p < 0.001). Similarly, the mean ratio between tumour and healthy glandular tissue in breast cancer patients (3.15 ± 1.58) was found to be significantly higher than the ratio for benign lesions (1.17 ± 0.41, p < 0.001). CONCLUSION PEM is capable of differentiating breast tumours from benign lesions with 100% sensitivity along with a high specificity of 96%, when a threshold of PUVmax >1.9 is applied.

Rituximab Maintenance for a Maximum of 5 Years After Single-Agent Rituximab Induction in Follicular Lymphoma: Results of the Randomized Controlled Phase III Trial SAKK 35/03.

PURPOSE Rituximab maintenance therapy has been shown to improve progression-free survival in patients with follicular lymphoma; however, the optimal duration of maintenance treatment remains unknown. PATIENTS AND METHODS Two hundred seventy patients with untreated, relapsed, stable, or chemotherapy-resistant follicular lymphoma were treated with four doses of rituximab monotherapy in weekly intervals (375 mg/m(2)). Patients achieving at least a partial response were randomly assigned to receive maintenance therapy with one infusion of rituximab every 2 months, either on a short-term schedule (four administrations) or a long-term schedule (maximum of 5 years or until disease progression or unacceptable toxicity). The primary end point was event-free survival (EFS). Progression-free survival, overall survival (OS), and toxicity were secondary end points. Comparisons between the two arms were performed using the log-rank test for survival end points. RESULTS One hundred sixty-five patients were randomly assigned to the short-term (n = 82) or long-term (n = 83) maintenance arms. Because of the low event rate, the final analysis was performed after 95 events had occurred, which was before the targeted event number of 99 had been reached. At a median follow-up period of 6.4 years, the median EFS was 3.4 years (95% CI, 2.1 to 5.3) in the short-term arm and 5.3 years (95% CI, 3.5 to not available) in the long-term arm (P = .14). Patients in the long-term arm experienced more adverse effects than did those in the short-term arm, with 76% v 50% of patients with at least one adverse event (P < .001), five versus one patient with grade 3 and 4 infections, and three versus zero patients discontinuing treatment because of unacceptable toxicity, respectively. There was no difference in OS between the two groups. CONCLUSION Long-term rituximab maintenance therapy does not improve EFS, which was the primary end point of this trial, or OS, and was associated with increased toxicity.