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Understanding the causes of recent climatic trends and variability in the high-latitude Southern Hemisphere is hampered by a short instrumental record. Here, we analyse recent atmosphere, surface ocean and sea-ice observations in this region and assess their trends in the context of palaeoclimate records and climate model simulations. Over the 36-year satellite era, significant linear trends in annual mean sea-ice extent, surface temperature and sea-level pressure are superimposed on large interannual to decadal variability. Most observed trends, however, are not unusual when compared with Antarctic palaeoclimate records of the past two centuries. With the exception of the positive trend in the Southern Annular Mode, climate model simulations that include anthropogenic forcing are not compatible with the observed trends. This suggests that natural variability overwhelms the forced response in the observations, but the models may not fully represent this natural variability or may overestimate the magnitude of the forced response.

Plateau icefields are large stores of freshwater, preconditioned to enhanced mass loss due to their gently sloping accumulation areas. Accurately modelling the mass-balance of these icefields is therefore vital for obtaining projections of their future contribution to sea-level rise. Here, we use the COupled Snowpack and Ice surface energy and mass-balance model in PYthon (COSIPY) to simulate the historical and potential future mass balance of the Juneau Icefield, Alaska -- a high elevation (>1200 m) plateau icefield. We force the model with dynamically downscaled climate simulations, pertaining to both the past and potential future (RCP 8.5) conditions. The rich dataset of surface mass balance observations of the Juneau Icefield allows us to tune COSIPY, providing confidence in our future predictions and highlighting changes to the icefield between the years 1980 and 2019. Icefield-wide negative mass balances were simulated from the start of the 21st century, as many glaciers transitioned from positive to negative mass-balances. Under RCP8.5, the model simulates increasing negative mass balance across Juneau Icefield, with the entire icefield potentially displaying a negative mass balance by the mid-21st century. This simulated loss of accumulation is driven by increased temperatures and reduced amounts of snowfall, exposing more of the icefield to thinning. Ice thinning is likely to be exacerbated by the exposure of ice to melting across the plateau surface, and prolonged melt may lead to an increase in disconnections, splitting glaciers between their accumulation and ablation areas at icefalls. The similar hypsometry of other high latitude plateau icefields and ice caps may mean that similar processes will act to determine their potential fate in our changing climate. [ABSTRACT FROM AUTHOR]

The occurrence and impact of fructose in the American food supply has garnered much recent attention in the popular press as well as the scientific community. This paper provides an overview of a workshop cosponsored by the International Life Sciences Institute North America and the USDA, Agricultural Research Service, titled 'State of the Science on Dietary Sweeteners Containing Fructose.' Papers in the workshop addressed the chemical composition and properties of dietary sweeteners that contain fructose, the sources and amount of fructose in the American diet, and the metabolism of fructose in the human body. Further, the authors of each paper assessed the strength of the existing data linking dietary fructose intake and risk for overweight, metabolic syndrome, type 2 diabetes mellitus, cardiovascular disease, and other disorders. The assessment considered factors in study design, including the amount fed, the food form, the length of the study, the characteristics of the subjects, the specific methodology, and other potential confounders including diet. In addition to papers assessing the basic science of fructose, some papers also addressed consumer concern about sugars and fructose in the diet, the way fructose and other sugars are presented in the media, and the resulting confusion of consumers about fructose and other sugars in the diet. The purpose of the papers in the aggregate was to clarify what data exist about fructose and what the gaps are in the data and to help both scientists and consumers understand issues surrounding fructose in the food supply.

The nonsynonymous variants of lipid phosphatase (FIG4) in patients with amyotrophic lateral sclerosis (ALS) and primary lateral sclerosis (PLS) is described. Heterozygosity for a deleterious allele FIG 4 that regulates PI(3,5)[P.sub.2] is found to be a risk factor for ALS and PLS, extending the list of known ALS genes and increasing the clinical spectrum of FIG4-related diseases.

The auxiliary spliceosomal protein SCNM1 contributes to recognition of nonconsensus splice donor sites. SCNM1 was first identified as a modifier of the severity of a sodium channelopathy in the mouse. The most severely affected strain, C57BL/6J, carries the variant allele SCN[M1.sup.R187TX], which is defective in splicing the mutated donor site in the Scn[8a.sup.medJ] transcript. To further probe the in vivo function of SCNM1, we constructed a floxed allele and generated a mouse with constitutive deletion of exons 3-5. The SCN[M1.sup.[DELTA]3-5] protein is produced and correctly localized to the nucleus, but is more functionally impaired than the C57BL/6J allele. Deficiency of SCNM1 did not significantly alter other brain transcripts. We characterized an ENU-induced allele of Scnm1 and evaluated the ability of wild-type SCNM1 to rescue lethal mutations of I-mfa and Brunol4. The phenotypes of the Scn[ml.sup.[DELTA]3-5] mutant confirm the role of this splice factor in processing the Scn[8a.sup.medJ] transcript and provide a new allele of greater severity for future studies.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jada.2006.09.033 Byline: Marci J. Levine, Julie M. Jones, David R. Lineback

Author(s): Julie M. Jones [1]; Pinaki Datta [4]; Srinivasa M. Srinivasula [4]; Weizhen Ji [1]; Sanjeev Gupta [4]; ZhiJia Zhang [4]; Erika Davies [5]; György Hajnóczky [5]; Thomas L. Saunders [...]