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Following the suggestions of a recent National Research Council report [NRC (National Research Council) (2006) Surface Temperature Reconstructions for the Last 2,000 Years (Natl Acad Press, Washington, DC).), we reconstruct surface temperature at hemispheric and global scale for much of the last 2,000 years using a greatly expanded set of proxy data for decadal-to-centennial climate changes, recently updated instrumental data, and complementary methods that have been thoroughly tested and validated with model simulation experiments. Our results extend previous conclusions that recent Northern Hemisphere surface temperature increases are likely anomalous in a long-term context. Recent warmth appears anomalous for at least the past 1,300 years whether or not tree-ring data are used. If tree-ring data are used, the conclusion can be extended to at least the past 1,700 years, but with additional strong caveats. The reconstructed amplitude of change over past centuries is greater than hitherto reported, with somewhat greater Medieval warmth in the Northern Hemisphere, albeit still not reaching recent levels. [ABSTRACT FROM AUTHOR]

The increasing complexity and diversity of a typical portfolio of research awards coupled with advancing technology makes successful implementation and delivery of system benefits more challenging than ever. Moreover, the role of systems in knowledge management is a fundamental issue faced by all research active organizations. One of the principal drivers for introducing better systems should be to serve the academic mission and make life easier for researchers; yet most appear to perform conversely, perhaps sacrificing potential benefits to meet the requirements of administration. The principal challenge thus is to deliver a system that meets the needs of both academic and administrative communities. This paper provides a commentary on the experience gained within a research office following implementation of two systems (one pre-award, the other post-award) and identifies key elements for successful delivery. The paper contains suggestions, based on our experience, of best practices and techniques that research administrators might adopt to ensure a well-managed project and its implementation. It concludes how, post implementation, users may begin to derive maximum benefit from systems and points to the advantages that high-quality knowledge management can offer a range of stakeholders. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented surrounding the technical issues about the SK07 construction equipment.

Two widely used statistical approaches to reconstructing past climate histories from climate “proxy” data such as tree rings, corals, and ice cores are investigated using synthetic “pseudoproxy” data derived from a simulation of forced climate changes over the past 1200 yr. These experiments suggest that both statistical approaches should yield reliable reconstructions of the true climate history within estimated uncertainties, given estimates of the signal and noise attributes of actual proxy data networks. [ABSTRACT FROM AUTHOR]

Purpose To compare in a group of patients with cerebral gliomas the estimates of Ktrans between a conventionally established pharmacokinetic model and a recently developed first pass method. Materials and Methods Glioma patients (23) were studied using T1-weighted dynamic contrast-enhanced magnetic resonance imaging (MRI), and two alternative pharmacokinetic models were used for analysis to derive the volume transfer constant Ktrans. These were a modified version of the established model (yielding KTK) and a recently published method based on first pass leakage profile (FP) of contrast bolus (yielding Kfp). Results We found a strong correlation between intra-tumoral median KTK and Kfp (rho = 0.650, P < 0.01), but the values from the conventional model were consistently and significantly higher (mean of inter-tumoral Kfp and KTK medians were 0.018 minute−1 and 0.284 minute−1, respectively, P < 0.001). The spatial distribution of KTK and Kfp showed poor correlation in the presence of large vascular structures and good correlation elsewhere. Conclusion KTK and Kfp produce similar biologic information within voxels not dominated by vascular tissue. The FP method avoids erroneous overestimation of Ktrans in areas of significant intravascular contrast. Findings are in keeping with the predictions of previous mathematical simulations. J. Magn. Reson. Imaging 2004;19:527-536. © 2004 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Global maps of sulfate and methane in marine sediments reveal two provinces of subsurface metabolic activity: a sulfate-rich open-ocean province, and an ocean-margin province where sulfate is limited to shallow sediments. Methane is produced in both regions but is abundant only in sulfate-depleted sediments. Metabolic activity is greatest in narrow zones of sulfate-reducing methane oxidation along ocean margins. The metabolic rates of subseafloor life are orders of magnitude lower than those of life on Earth's surface. Most microorganisms in subseafloor sediments are either inactive or adapted for extraordinarily low metabolic activity. [ABSTRACT FROM AUTHOR]

Examines the phase evolution of precession and semiprecession cycles in the tropical and extra-tropical Atlantic Ocean. Purpose of the study to explain changes in the Earth's glacial cycles during the Pleistocene epoch; Conclusion that heat flow across the equator to higher latitudes strengthened the semiprecession cycle in the Northern Hemisphere and triggered the transition to sustained glacial cycles.

Background: Neurofibromatosis Type 2 (NF2) is a dominantly inherited tumour syndrome with a phenotype which includes bilateral vestibular (eighth cranial nerve) schwannomas. Conventional thinking suggests that these tumours originate at a single point along the superior division of the eighth nerve. Methods: High resolution MRI was performed in children genetically proven to have NF2. The superior vestibular nerve (SVN) and inferior vestibular nerve (IVN) were visualised along their course with points of tumour origin calculated as a percentage relative to the length of the nerve. Results: Out of 41 patients assessed, 7 patients had no identifiable eighth cranial nerve disease. In 16 patients there was complete filling of the internal auditory meatus by a tumour mass such that its specific neural origin could not be determined. In the remaining 18 cases, 86 discrete separate foci of tumour origin on the SVN or IVN could be identified including 23 tumours on the right SVN, 26 tumours on the right IVN, 18 tumours on the left SVN and 19 tumours on the left IVN. Discussion This study, examining the origins of vestibular schwannomas in NF2, refutes their origin as being from a single site on the transition zone of the superior division of the vestibular nerve. We hypothesise a relationship between the number of tumour foci, tumour biology and aggressiveness of disease. The development of targeted drug therapies in addition to bevacizumab are therefore essential to improve prognosis and quality of life in patients with NF2 given the shortcomings of surgery and radiation treatments when dealing with the multifocality of the disease.

Presents data from research which used assemblages of planktic foraminifera from surface sediments to test the hypotheses regarding the geographic distribution of zooplankton diversity. Indications that zooplankton diversity may be controlled by the physical structure of the near-surface ocean.

analyzes the total clutch volumes and condition of female ducks relative to their haemosporidian blood parasite loads. No significant relationships found between clutch volume and parasitism; Data showing that blood parasites were relatively benign with respect to reproductive investment.

Smerdon et al. report two errors in the climate model grid data used in previous pseudoproxy-based climate reconstruction experiments that do not impact the main conclusions of those works. The errors did not occur in subsequent works and therefore have no impact on the results presented therein. Results presented here for the Climate System Model (CSM) using multiple pseudoproxy noise realizations show that the quantitative differences between the incorrect and corrected results are within the expected variability of the noise realizations. It should also be made clear that the climate reconstruction method used in Smerdon et al. to illustrate the nature of the errors, the Regularized Expectation Maximization method with Ridge Regression (RegEM-Ridge), is known to produce climate reconstructions with considerable variance loss and has been superseded by RegEM-TTLS (TTLS indicates truncated total least squares). [ABSTRACT FROM AUTHOR]