Simultaneous control of magnetic topologies for reconfigurable vortex arrays

The topological spin textures in magnetic vortices in confined magnetic elements offer a platform for understanding the fundamental physics of nanoscale spin behavior and the potential of harnessing their unique spin structures for advanced magnetic technologies. For magnetic vortices to be practical, an effective reconfigurability of the two topologies of magnetic vortices, that is, the circularity and the polarity, is an essential prerequisite. The reconfiguration issue is highly relevant to the question of whether both circularity and polarity are reliably and efficiently controllable. In this work, we report the first direct observation of simultaneous control of both circularity and polarity by the sole application of an in-plane magnetic field to arrays of asymmetrically shaped permalloy disks. Our investigation demonstrates that a high degree of reliability for control of both topologies can be achieved by tailoring the geometry of the disk arrays. We also propose a new approach to control the vortex structures by manipulating the effect of the stray field on the dynamics of vortex creation. The current study is expected to facilitate complete and effective reconfiguration of magnetic vortex structures, thereby enhancing the prospects for technological applications of magnetic vortices.ope

Multigene Phylogeny of Choanozoa and the Origin of Animals

Animals are evolutionarily related to fungi and to the predominantly unicellular protozoan phylum Choanozoa, together known as opisthokonts. To establish the sequence of events when animals evolved from unicellular ancestors, and understand those key evolutionary transitions, we need to establish which choanozoans are most closely related to animals and also the evolutionary position of each choanozoan group within the opisthokont phylogenetic tree. Here we focus on Ministeria vibrans, a minute bacteria-eating cell with slender radiating tentacles. Single-gene trees suggested that it is either the closest unicellular relative of animals or else sister to choanoflagellates, traditionally considered likely animal ancestors. Sequencing thousands of Ministeria protein genes now reveals about 14 with domains of key significance for animal cell biology, including several previously unknown from deeply diverging Choanozoa, e.g. domains involved in hedgehog, Notch and tyrosine kinase signaling or cell adhesion (cadherin). Phylogenetic trees using 78 proteins show that Ministeria is not sister to animals or choanoflagellates (themselves sisters to animals), but to Capsaspora, another protozoan with thread-like (filose) tentacles. The Ministeria/Capsaspora clade (new class Filasterea) is sister to animals and choanoflagellates, these three groups forming a novel clade (filozoa) whose ancestor presumably evolved filose tentacles well before they aggregated as a periciliary collar in the choanoflagellate/sponge common ancestor. Our trees show ichthyosporean choanozoans as sisters to filozoa; a fusion between ubiquitin and ribosomal small subunit S30 protein genes unifies all holozoa (filozoa plus Ichthyosporea), being absent in earlier branching eukaryotes. Thus, several successive evolutionary innovations occurred among their unicellular closest relatives prior to the origin of the multicellular body-plan of animals

Genetic Determinants of Variability in Glycated Hemoglobin (HbA1c) in Humans: Review of Recent Progress and Prospects for Use in Diabetes Care

Glycated hemoglobin A1c (HbA1c) indicates the percentage of total hemoglobin that is bound by glucose, produced from the nonenzymatic chemical modification by glucose of hemoglobin molecules carried in erythrocytes. HbA1c represents a surrogate marker of average blood glucose concentration over the previous 8 to 12 weeks, or the average lifespan of the erythrocyte, and thus represents a more stable indicator of glycemic status compared with fasting glucose. HbA1c levels are genetically determined, with heritability of 47% to 59%. Over the past few years, inroads into understanding genetic predisposition by glycemic and nonglycemic factors have been achieved through genome-wide analyses. Here I review current research aimed at discovering genetic determinants of HbA1c levels, discussing insights into biologic factors influencing variability in the general and diabetic population, and across different ethnicities. Furthermore, I discuss briefly the relevance of findings for diabetes monitoring and diagnosis

Transferability of Type 2 Diabetes Implicated Loci in Multi-Ethnic Cohorts from Southeast Asia

Recent large genome-wide association studies (GWAS) have identified multiple loci which harbor genetic variants associated with type 2 diabetes mellitus (T2D), many of which encode proteins not previously suspected to be involved in the pathogenesis of T2D. Most GWAS for T2D have focused on populations of European descent, and GWAS conducted in other populations with different ancestry offer a unique opportunity to study the genetic architecture of T2D. We performed genome-wide association scans for T2D in 3,955 Chinese (2,010 cases, 1,945 controls), 2,034 Malays (794 cases, 1,240 controls), and 2,146 Asian Indians (977 cases, 1,169 controls). In addition to the search for novel variants implicated in T2D, these multi-ethnic cohorts serve to assess the transferability and relevance of the previous findings from European descent populations in the three major ethnic populations of Asia, comprising half of the world's population. Of the SNPs associated with T2D in previous GWAS, only variants at CDKAL1 and HHEX/IDE/KIF11 showed the strongest association with T2D in the meta-analysis including all three ethnic groups. However, consistent direction of effect was observed for many of the other SNPs in our study and in those carried out in European populations. Close examination of the associations at both the CDKAL1 and HHEX/IDE/KIF11 loci provided some evidence of locus and allelic heterogeneity in relation to the associations with T2D. We also detected variation in linkage disequilibrium between populations for most of these loci that have been previously identified. These factors, combined with limited statistical power, may contribute to the failure to detect associations across populations of diverse ethnicity. These findings highlight the value of surveying across diverse racial/ethnic groups towards the fine-mapping efforts for the casual variants and also of the search for variants, which may be population-specific

A Cross-Species Analysis of MicroRNAs in the Developing Avian Face

Higher vertebrates use similar genetic tools to derive very different facial features. This diversity is believed to occur through temporal, spatial and species-specific changes in gene expression within cranial neural crest (NC) cells. These contribute to the facial skeleton and contain species-specific information that drives morphological variation. A few signaling molecules and transcription factors are known to play important roles in these processes, but little is known regarding the role of micro-RNAs (miRNAs). We have identified and compared all miRNAs expressed in cranial NC cells from three avian species (chicken, duck, and quail) before and after species-specific facial distinctions occur. We identified 170 differentially expressed miRNAs. These include thirty-five novel chicken orthologs of previously described miRNAs, and six avian-specific miRNAs. Five of these avian-specific miRNAs are conserved over 120 million years of avian evolution, from ratites to galliforms, and their predicted target mRNAs include many components of Wnt signaling. Previous work indicates that mRNA gene expression in NC cells is relatively static during stages when the beak acquires species-specific morphologies. However, miRNA expression is remarkably dynamic within this timeframe, suggesting that the timing of specific developmental transitions is altered in birds with different beak shapes. We evaluated one miRNA:mRNA target pair and found that the cell cycle regulator p27KIP1 is a likely target of miR-222 in frontonasal NC cells, and that the timing of this interaction correlates with the onset of phenotypic variation. Our comparative genomic approach is the first comprehensive analysis of miRNAs in the developing facial primordial, and in species-specific facial development

Understanding acute ankle ligamentous sprain injury in sports

This paper summarizes the current understanding on acute ankle sprain injury, which is the most common acute sport trauma, accounting for about 14% of all sport-related injuries. Among, 80% are ligamentous sprains caused by explosive inversion or supination. The injury motion often happens at the subtalar joint and tears the anterior talofibular ligament (ATFL) which possesses the lowest ultimate load among the lateral ligaments at the ankle. For extrinsic risk factors to ankle sprain injury, prescribing orthosis decreases the risk while increased exercise intensity in soccer raises the risk. For intrinsic factors, a foot size with increased width, an increased ankle eversion to inversion strength, plantarflexion strength and ratio between dorsiflexion and plantarflexion strength, and limb dominance could increase the ankle sprain injury risk. Players with a previous sprain history, players wearing shoes with air cells, players who do not stretch before exercising, players with inferior single leg balance, and overweight players are 4.9, 4.3, 2.6, 2.4 and 3.9 times more likely to sustain an ankle sprain injury. The aetiology of most ankle sprain injuries is incorrect foot positioning at landing – a medially-deviated vertical ground reaction force causes an explosive supination or inversion moment at the subtalar joint in a short time (about 50 ms). Another aetiology is the delayed reaction time of the peroneal muscles at the lateral aspect of the ankle (60–90 ms). The failure supination or inversion torque is about 41–45 Nm to cause ligamentous rupture in simulated spraining tests on cadaver. A previous case report revealed that the ankle joint reached 48 degrees inversion and 10 degrees internal rotation during an accidental grade I ankle ligamentous sprain injury during a dynamic cutting trial in laboratory. Diagnosis techniques and grading systems vary, but the management of ankle ligamentous sprain injury is mainly conservative. Immobilization should not be used as it results in joint stiffness, muscle atrophy and loss of proprioception. Traditional Chinese medicine such as herbs, massage and acupuncture were well applied in China in managing sports injuries, and was reported to be effective in relieving pain, reducing swelling and edema, and restoring normal ankle function. Finally, the best practice of sports medicine would be to prevent the injury. Different previous approaches, including designing prophylactice devices, introducing functional interventions, as well as change of games rules were highlighted. This paper allows the readers to catch up with the previous researches on ankle sprain injury, and facilitate the future research idea on sport-related ankle sprain injury

Association of genetic variation in FTO with risk of obesity and type 2 diabetes with data from 96,551 East and South Asians

Aims/hypothesis: $FTO$ harbours the strongest known obesity-susceptibility locus in Europeans. While there is growing evidence for a role for $FTO$ in obesity risk in Asians, its association with type 2 diabetes, independently of BMI, remains inconsistent. To test whether there is an association of the $FTO$ locus with obesity and type 2 diabetes, we conducted a meta-analysis of 32 populations including 96,551 East and South Asians. Methods: All studies published on the association between $FTO$-rs9939609 (or proxy [r$^2$ > 0.98]) and BMI, obesity or type 2 diabetes in East or South Asians were invited. Each study group analysed their data according to a standardised analysis plan. Association with type 2 diabetes was also adjusted for BMI. Random-effects meta-analyses were performed to pool all effect sizes. Results: The $FTO$-rs9939609 minor allele increased risk of obesity by 1.25-fold/allele (p = 9.0 × 10$^{−19}$), overweight by 1.13-fold/allele (p = 1.0 × 10$^{−11}$) and type 2 diabetes by 1.15-fold/allele (p = 5.5 × 10$^{−8}$). The association with type 2 diabetes was attenuated after adjustment for BMI (OR 1.10-fold/allele, p = 6.6 × 10$^{−5}$). The $FTO$-rs9939609 minor allele increased BMI by 0.26 kg/m2 per allele (p = 2.8 × 10$^{−17}$), WHR by 0.003/allele (p = 1.2 × 10$^{−6}$), and body fat percentage by 0.31%/allele (p = 0.0005). Associations were similar using dominant models. While the minor allele is less common in East Asians (12–20%) than South Asians (30–33%), the effect of $FTO$ variation on obesity-related traits and type 2 diabetes was similar in the two populations. Conclusions/interpretation: $FTO$ is associated with increased risk of obesity and type 2 diabetes, with effect sizes similar in East and South Asians and similar to those observed in Europeans. Furthermore, $FTO$ is also associated with type 2 diabetes independently of BMI. Electronic supplementary material The online version of this article (doi:10.1007/s00125-011-2370-7) contains peer-reviewed but unedited supplementary material, which is available to authorised users