Optimized unconventional superconductivity in a molecular Jahn-Teller metal

Understanding the relationship between the superconducting, the neighboring insulating, and the normal metallic state above Tc is a major challenge for all unconventional superconductors. The molecular A3C60 fulleride superconductors have a parent antiferromagnetic insulator in common with the atom-based cuprates, but here, the C603– electronic structure controls the geometry and spin state of the structural building unit via the on-molecule Jahn-Teller effect. We identify the Jahn-Teller metal as a fluctuating microscopically heterogeneous coexistence of both localized Jahn-Teller–active and itinerant electrons that connects the insulating and superconducting states of fullerides. The balance between these molecular and extended lattice features of the electrons at the Fermi level gives a dome-shaped variation of Tc with interfulleride separation, demonstrating molecular electronic structure control of superconductivity

Case report on trial: Do you, Doctor, swear to tell the truth, the whole truth and nothing but the truth?

We are in the era of "evidence based medicine" in which our knowledge is stratified from top to bottom in a hierarchy of evidence. Many in the medical and dental communities highly value randomized clinical trials as the gold standard of care and undervalue clinical reports. The aim of this editorial is to emphasize the benefits of case reports in dental and oral medicine, and encourage those of us who write and read them

Association Between Periodontitis and Impaired Fasting Glucose and Diabetes

OBJECTIVEMany studies have reported that periodontal disease is associated with diabetes, but its relation with impaired fasting glucose (IFG) has been understudied. This study investigated the relationship between chronic periodontitis, IFG, and diabetes in the U.S. population.RESEARCH DESIGN AND METHODSParticipants in the National Health and Nutrition Examination Survey III, aged ≥20 years, who received periodontal examinations and provided blood samples (n = 12,254) were grouped into quintiles of mean clinical attachment loss (CAL) and pocket depth, with the lowest category being the reference. Plasma fasting glucose was categorized into three groups (normal, <100 mg/dL; IFG, ≥100 but <126 mg/dL; and diabetic, ≥126 mg/dL). Sociodemographic factors and other potential risk factors were obtained by interview or examination. SAS 9.1 was used for statistical analysis accounting for the complex weighted sampling.RESULTSParticipants in the top quintile category of CAL had higher prevalence odds of IFG (odds ratio [OR] 1.55 [95% CI 1.16–2.07]) and diabetes (4.77 [2.69–8.46]) after adjustment for related confounders, compared with those in the bottom quintile. The highest quintile of pocket depth was positively associated with IFG (1.39 [1.00–1.92]) and diabetes (1.63 [1.10–2.42]) compared with the lowest quintile. ORs for CAL increased from the lowest to the highest quintile (P value test for trend <0.01) for all outcomes. The ORs for pocket depth also tended to rise across quintiles.CONCLUSIONSChronic periodontitis measured by CAL and pocket depth was positively associated in a linear relation with IFG and diabetes in U.S. adults

Subdividing Y-chromosome haplogroup R1a1 reveals Norse Viking dispersal lineages in Britain

The influence of Viking-Age migrants to the British Isles is obvious in archaeological and place-names evidence, but their demographic impact has been unclear. Autosomal genetic analyses support Norse Viking contributions to parts of Britain, but show no signal corresponding to the Danelaw, the region under Scandinavian administrative control from the ninth to eleventh centuries. Y-chromosome haplogroup R1a1 has been considered as a possible marker for Viking migrations because of its high frequency in peninsular Scandinavia (Norway and Sweden). Here we select ten Y-SNPs to discriminate informatively among hg R1a1 sub-haplogroups in Europe, analyse these in 619 hg R1a1 Y chromosomes including 163 from the British Isles, and also type 23 short-tandem repeats (Y-STRs) to assess internal diversity. We find three specifically Western-European sub-haplogroups, two of which predominate in Norway and Sweden, and are also found in Britain; starlike features in the STR networks of these lineages indicate histories of expansion. We ask whether geographical distributions of hg R1a1 overall, and of the two sub-lineages in particular, correlate with regions of Scandinavian influence within Britain. Neither shows any frequency difference between regions that have higher (≥10%) or lower autosomal contributions from Norway and Sweden, but both are significantly overrepresented in the region corresponding to the Danelaw. These differences between autosomal and Y-chromosomal histories suggest either male-specific contribution, or the influence of patrilocality. Comparison of modern DNA with recently available ancient DNA data supports the interpretation that two sub-lineages of hg R1a1 spread with the Vikings from peninsular Scandinavia

The Y-Chromosome Tree Bursts into Leaf: 13,000 High-Confidence SNPs Covering the Majority of Known Clades

Many studies of human populations have used the male-specific region of the Y chromosome (MSY) as a marker, but MSY sequence variants have traditionally been subject to ascertainment bias. Also, dating of haplogroups has relied on Y-specific short tandem repeats (STRs), involving problems of mutation rate choice, and possible long-term mutation saturation. Next-generation sequencing can ascertain single nucleotide polymorphisms (SNPs) in an unbiased way, leading to phylogenies in which branch-lengths are proportional to time, and allowing the times-to-most-recent-common-ancestor (TMRCAs) of nodes to be estimated directly. Here we describe the sequencing of 3.7 Mb of MSY in each of 448 human males at a mean coverage of 51x, yielding 13,261 high-confidence SNPs, 65.9% of which are previously unreported. The resulting phylogeny covers the majority of the known clades, provides date estimates of nodes, and constitutes a robust evolutionary framework for analyzing the history of other classes of mutation. Different clades within the tree show subtle but significant differences in branch lengths to the root. We also apply a set of 23 Y-STRs to the same samples, allowing SNP- and STR-based diversity and TMRCA estimates to be systematically compared. Ongoing purifying selection is suggested by our analysis of the phylogenetic distribution of nonsynonymous variants in 15 MSY single-copy genes

The effect of swimming on oral health status: competitive versus non-competitive athletes

ABSTRACT Young swimmers are particularly susceptible to the onset of oral diseases. Objective To evaluate the oral health status in young competitive and non-competitive swimmers, involving an assessment of salivary cariogenic bacteria and secretory IgA (S-IgA) concentration. Material and Methods Before training sessions (T1), 54 competitive and 69 non-competitive swimmers had the following parameters assessed: decayed, missing, and filled teeth (DMFT), Plaque Index (PlI), and Gingival Index (GI). At T1 and after training sessions (T2), stimulated saliva was collected and microbiological and immunological analyses were performed. Results Competitive swimmers trained 2.02±0.09 hours 5 times a week, while non-competitive swimmers trained 2.03±0.18 hours a week. A total of 14.7% of competitive swimmers suffered dental trauma related to sports. Only 11.76% of the competitive swimmers took a daily dose of fluoride, against 32.65% of non-competitive swimmers (p=0.029). Neither group followed an established diet or presented statistically significant differences in terms of nutritional supplement drink and chocolate intake. There were statistically significant differences in terms of oral hygiene. No significant difference in clinical indexes (DMFT, PlI, and GI) was present. S. mutans was harbored by 18.6% of competitive and the 32.2% of non-competitive swimmers. S. sobrinus was detected in 22.03% of competitive and 91.6% of non-competitive swimmers (p<0.05). S. sanguinis was found only in the saliva of competitive swimmers. The average S-IgA of competitive swimmers decreased significantly at T2 (p<0.05). The pool water had a daily average pH of 7.22. Conclusions Microbial markers, immune status and sporting characteristics are important for establishing guidelines for management of training load in order to minimize physical stress and the risk of oral infection

Parent-of-origin-specific allelic associations among 106 genomic loci for age at menarche.

Age at menarche is a marker of timing of puberty in females. It varies widely between individuals, is a heritable trait and is associated with risks for obesity, type 2 diabetes, cardiovascular disease, breast cancer and all-cause mortality. Studies of rare human disorders of puberty and animal models point to a complex hypothalamic-pituitary-hormonal regulation, but the mechanisms that determine pubertal timing and underlie its links to disease risk remain unclear. Here, using genome-wide and custom-genotyping arrays in up to 182,416 women of European descent from 57 studies, we found robust evidence (P < 5 × 10(-8)) for 123 signals at 106 genomic loci associated with age at menarche. Many loci were associated with other pubertal traits in both sexes, and there was substantial overlap with genes implicated in body mass index and various diseases, including rare disorders of puberty. Menarche signals were enriched in imprinted regions, with three loci (DLK1-WDR25, MKRN3-MAGEL2 and KCNK9) demonstrating parent-of-origin-specific associations concordant with known parental expression patterns. Pathway analyses implicated nuclear hormone receptors, particularly retinoic acid and γ-aminobutyric acid-B2 receptor signalling, among novel mechanisms that regulate pubertal timing in humans. Our findings suggest a genetic architecture involving at least hundreds of common variants in the coordinated timing of the pubertal transition

Genome sequence analyses of two isolates from the recent Escherichia coli outbreak in Germany reveal the emergence of a new pathotype: Entero-Aggregative-Haemorrhagic Escherichia coli (EAHEC)

The genome sequences of two Escherichia coli O104:H4 strains derived from two different patients of the 2011 German E. coli outbreak were determined. The two analyzed strains were designated E. coli GOS1 and GOS2 (German outbreak strain). Both isolates comprise one chromosome of approximately 5.31 Mbp and two putative plasmids. Comparisons of the 5,217 (GOS1) and 5,224 (GOS2) predicted protein-encoding genes with various E. coli strains, and a multilocus sequence typing analysis revealed that the isolates were most similar to the entero-aggregative E. coli (EAEC) strain 55989. In addition, one of the putative plasmids of the outbreak strain is similar to pAA-type plasmids of EAEC strains, which contain aggregative adhesion fimbrial operons. The second putative plasmid harbors genes for extended-spectrum β-lactamases. This type of plasmid is widely distributed in pathogenic E. coli strains. A significant difference of the E. coli GOS1 and GOS2 genomes to those of EAEC strains is the presence of a prophage encoding the Shiga toxin, which is characteristic for enterohemorrhagic E. coli (EHEC) strains. The unique combination of genomic features of the German outbreak strain, containing characteristics from pathotypes EAEC and EHEC, suggested that it represents a new pathotype Entero-Aggregative-Haemorrhagic Escherichiacoli (EAHEC)