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The Western Siberia Lowland (WSL), the world’s largest permafrost peatland, is of importance for understanding the high-latitude carbon (C) cycle and its response to climate change. Warming temperatures increase permafrost thaw and production of greenhouse gases. Also, permafrost thaw leads to the formation of lakes which are hotspots for atmospheric C emissions. Although lakes occupy ~6% of WSL, lake C emissions from WSL remain poorly quantified. Here we show high C emissions from lakes across all permafrost zones of WSL. The C emissions were especially high in shoulder seasons and in colder permafrost-rich regions. The total C emission from permafrost-affected lakes of WSL equals ~12 ± 2.6 Tg C yr −1 and is 2-times greater than region’s C export to the Arctic coast. The results show that C emission from WSL lakes is a significant component in the high-latitude C cycle, but also suggest that C emission may decrease with warming. The Western Siberia Lowland (WSL) is the world’s largest frozen peatland complex, however carbon emissions (CO 2 +CH 4 ) from lakes in this region remain unknown. Here, the authors sample 76 lakes and show high carbon emissions from lakes across all permafrost zones in the WSL.

Thermokarst (thaw) lakes of the Western Siberian Lowland (WSL), the World´s largest permafrost peatland, contain important but poorly constrained stocks of organic carbon (OC) and nitrogen. These lakes are highly vulnerable to climate warming and permafrost thaw. The present work aims to quantify the OC and total nitrogen (TN) stocks and accumulation rates in sediments of 11 thermokarst lakes in the WSL across a permafrost gradient, from isolated to discontinuous and continuous permafrost. We found an increase in OC and TN stocks in lake sediments (0–30 cm) from the northern taiga with sporadic permafrost (285 Tg C and 10.5 Tg N) to the tundra zone with continuous permafrost (628 Tg C and 26 Tg N). The upper 30 cm thermokarst lake sediments of the permafrost-affected WSL store 1250 ± 35 Tg C and 50 ± 1.4 Tg N). The OC accumulation rates in thermokarst lake sediments ranged from 36 to 250 g C m−2 year−1, which is 5 to 10 times higher than C accumulation rates in peatlands of western Siberia. The total OC accumulation in lakes of WSL is 7.8 ± 0.7 Tg C year−1. This is about 24–47% of the C emission from the WSL thermokarst lakes, implying that it represents an important factor in the C budget to consider in order to understand impacts of climate change and permafrost thaw on the C cycle.

Germline mutations in the LKB1/STK11 tumour suppressor gene cause Peutz–Jeghers syndrome (PJS), a rare dominant disorder. In addition to typical hamartomatous gastrointestinal polyps and pigmented perioral lesions, PJS is associated with an increased risk of tumours at multiple sites. Follow-up information on carriers is limited and genetic heterogeneity makes counselling and management in PJS difficult. Here we report the analysis of the LKB1/STK11 locus in a series of 33 PJS families, and estimation of cancer risks in carriers and noncarriers. Germline mutations of LKB1/STK11 were identified in 52% of cases. This observation reinforces the hypothesis of a second PJS locus. In carriers of LKB1/STK11 mutations, the risk of cancer was markedly elevated. The risk of developing any cancer in carriers by age 65 years was 47% (95% CI: 27–73%) with elevated risks of both gastrointestinal and breast cancer. PJS with germline mutations in LKB1/STK11 are at a very high relative and absolute risk of multiple gastrointestinal and nongastrointestinal cancers. To obtain precise estimates of risk associated with PJS requires further studies of genotype–phenotype especially with respect to LKB1/STK11 negative cases, as this group is likely to be heterogeneous.

Background: Peutz-Jeghers syndrome (PJS) is a rare, autosomal dominant cancer predisposition syndrome characterised by oro-facial pigmentation and hamartomatous polyposis of the gastrointestinal tract. A causal germline mutation in STK11 can be identified in 30% to 80% of PJS patients. Methods: Here we report the comprehensive mutational analysis of STK11 in 38 PJS probands applying conventional PCR based mutation detection methods and the recently introduced MLPA (multiplex ligation dependent probe amplification) technique developed for the identification of exonic deletions/duplications. Results: Nineteen of 38 probands (50%) had detectable point mutations or small scale deletions/insertions and six probands (16%) had genomic deletions encompassing one or more STK11 exons. Conclusions: These findings demonstrate that exonic STK11 deletions are a common cause of PJS and provide a strong rationale for conducting a primary screen for such mutations in patients.

In this study, we have provided new and important findings with regards to the spatial distribution of DOM concentration, bioavailability, and optical properties during early summer hydrologic conditions within the Bakcharsky bog complex in the southern taiga subzone of Western Siberia. Data on biodegradable fractions of DOM in surface and soil waters were obtained on the basis of laboratory experiments and analytical work. Surface and soil waters have landscape differences in their chemical composition. The lowest values of pH, DOC, degree of humification, Ca, Mg, Na, P, and Fe are characteristic of the open sedge-sphagnum fen. There is a different intensity of DOC degradation, depending on the microlandscape. The process of OM biodegradation occurs most significantly on the 7-14th day of the experiment. The maximum microbial decay of DOC, reaching in some cases ≥ 20%, is observed in river waters, and bog waters of the open sedge-sphagnum fen. UV-visible measurements showed that the SUVA254, E2:E3, E4:E6 ratios change during the incubation, while E2:E4 remain fairly constant over time.

We present the first direct search for lepton flavour violating muon decay mediated by a new light particle X, μ + → e + X , X → γ γ . This search uses a dataset resulting from 7.5 × 10 14 stopped muons collected by the MEG experiment at the Paul Scherrer Institut in the period 2009–2013. No significant excess is found in the mass region 20–45 MeV/c 2 for lifetimes below 40 ps, and we set the most stringent branching ratio upper limits in the mass region of 20–40 MeV/c 2 , down to O ( 10 - 11 ) at 90% confidence level.

At 34 weeks she underwent an emergency Caesarean section because of antepartum haemorrhage and a healthy baby girl (birth weight 2.07 kg) was delivered. Intravenous cyclosporin induced remission in our pregnant patient who had failed to respond to high dose oral and intravenous prednisolone.

The stratification of microorganisms along the depth of the column occurs during the processes of freezing and thawing. Two processes - sedimentation and freezing - are sufficient for the formation of a concentrated layer of microorganisms. By contrast, vertical transfer and concentration of nutrients from the surface layers or from the thawing underlying layer of permafrost are not required. The spatial distribution of soil microflora can serve as a marker of climatic changes in the studied region.

The aetiology of ulcerative colitis is unknown. Two patients without pre-existing inflammatory bowel disease in whom end colostomy for faecal incontinence was complicated by diversion colitis in the defunctioned rectosigmoid colon, are described. In both instances, colitis with the clinical, colonoscopic, and microscopic features of ulcerative colitis developed about a year later in the previously normal in-stream colon proximal to the colostomy. These cases suggest that diversion colitis may be a risk factor for ulcerative colitis in predisposed individuals and that ulcerative colitis can be triggered by anatomically discontinuous inflammation elsewhere in the large intestine.

A 53 year old man presented with severe neck pain and a flu-like illness; he had recently returned from Sri Lanka and had had dental treatment six days before illness onset. Blood culture showed infection by Haemophilus aphrophilus. Magnetic resonance imaging was performed and exploratory surgery undertaken. The prevertebral cervical fascia was inflamed but no abscess identified. He was treated with antibiotics and made an uneventful recovery.