Hydrogen-bonded liquid crystals with broad-range blue phases

We report a modular supramolecular approach for the investigation of chirality induction in hydrogen-bonded liquid crystals. An exceptionally broad blue phase with a temperature range of 25 °C was found, which enabled its structural investigation by solid state 19F-NMR studies and allowed us to report order parameters of the blue phase I for the first time

Hierarchical Self-Assembly of Halogen-Bonded Block Copolymer Complexes into Upright Cylindrical Domains

Self-assembly of block copolymers into well-defined, ordered arrangements of chemically distinct domains is a reliable strategy for preparing tailored nanostructures. Microphase separation results from the system, minimizing repulsive interactions between dissimilar blocks and maximizing attractive interactions between similar blocks. Supramolecular methods have also achieved this separation by introducing small-molecule additives binding specifically to one block by noncovalent interactions. Here, we use halogen bonding as a supramolecular tool that directs the hierarchical self-assembly of low-molecular-weight perfluorinated molecules and diblock copolymers. Microphase separation results in a lamellar-within-cylindrical arrangement and promotes upright cylindrical alignment in films upon rapid casting and without further annealing. Such cylindrical domains with internal lamellar self-assemblies can be cleaved by solvent treatment of bulk films, resulting in separated and segmented cylindrical micelles stabilized by halogen-bond-based supramolecular crosslinks. These features, alongside the reversible nature of halogen bonding, provide a robust modular approach for nanofabricatio

Adhesive incisional drapes during cesarean delivery for preventing wound infection: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE: To compare the incidence of wound infection after cesarean delivery in procedures conducted using adhesive incisional drapes verses no adhesive incisional drapes. STUDY DESIGN: Searches were performed in electronic databases (MEDLINE, ClinicalTrials.gov, the Cochrane Central Register of Controlled Trials, Scopus, OVID, EMBASE, and the PROSPERO International Prospective Register of Systematic Reviews). We included randomized controlled trials comparing adhesive incisional drapes to no adhesive incisional drapes during cesarean delivery. The primary outcome of this meta-analysis was wound infection. Meta-analysis was performed using the random effects model of DerSimonian and Laird, to produce relative risk (RR) with 95% confidence interval (CI). RESULTS: 52 publications were identified through initial search of databases and two randomized controlled trials were eligible and included in the meta-analysis. Our meta-analysis examined a total of 1943 subjects and showed a statistically significant increase in wound infections in patients in the adhesive incisional drape group when compared to the control group (RR: 1.29, 95% CI: 1.02-1.65). CONCLUSION: Adhesive incisional drapes may increase the incidence of wound infections after cesarean delivery. Further studies are necessary to explore this relationship in the setting of current postoperative infection prophylaxis, including broad-spectrum antibiotic coverage, skin preparation and vaginal cleansing

From Vertices to Vortices in magnetic nanoislands

Recent studies in magnetic nanolithography show that a variety of complex magnetic states emerge as a function of a single magnetic island's aspect ratio. We propose a model which, in addition to fitting experiments, predicts magnetic states with continuous symmetry at particular aspect ratios and reveals a duality between vortex and vertex states. Our model then opens new means of engineering novel types of artificial spin systems, and their application to complex magnetic textures in devices and computing.Comment: 3 pages + epsilon + 18 supplementary materia

Left-handers know what's left is right: handedness and object affordance

We live in a right-hander's world. Although left-handers become accustomed to using right-handed devices, an underlying preference for objects that afford the dominant hand could remain. We employed eye tracking while left- and right-handed participants viewed advertisements for everyday products. Participants then rated aesthetic appeal, purchase intention, and perceived value. Left-handed participants found advertisements for products that more easily afforded them action to be more aesthetically appealing. They also indicated greater future purchase intention for products that were oriented towards the left hand, and gave these products a higher perceived value. Eye tracking data showed that object handles attracted attention, and were also able to retain participants' attention. Further, across multiple eye movement measures, our data show that participant eye movements were altered by the orientation of the handle, such that this side of the image was examined earlier and for longer, regardless of handedness. Left-handers' preferences might be stronger because they are more aware of object orientation, whereas right-handers do not experience the same difficulties. These findings highlight intrinsic differences in the way in which we perceive objects and our underlying judgments about those products, based on handedness.Nicole A. Thomas, Rebekah Manning, Elizabeth J. Saccon

In search of causal variants: refining disease association signals using cross-population contrasts

<p>Abstract</p> <p>Background</p> <p>Genome-wide association (GWA) using large numbers of single nucleotide polymorphisms (SNPs) is now a powerful, state-of-the-art approach to mapping human disease genes. When a GWA study detects association between a SNP and the disease, this signal usually represents association with a set of several highly correlated SNPs in strong linkage disequilibrium. The challenge we address is to distinguish among these correlated loci to highlight potential functional variants and prioritize them for follow-up.</p> <p>Results</p> <p>We implemented a systematic method for testing association across diverse population samples having differing histories and LD patterns, using a logistic regression framework. The hypothesis is that important underlying biological mechanisms are shared across human populations, and we can filter correlated variants by testing for heterogeneity of genetic effects in different population samples. This approach formalizes the descriptive comparison of p-values that has typified similar cross-population fine-mapping studies to date. We applied this method to correlated SNPs in the cholinergic nicotinic receptor gene cluster <it>CHRNA5-CHRNA3-CHRNB4</it>, in a case-control study of cocaine dependence composed of 504 European-American and 583 African-American samples. Of the 10 SNPs genotyped in the r²≥ 0.8 bin for <it>rs16969968</it>, three demonstrated significant cross-population heterogeneity and are filtered from priority follow-up; the remaining SNPs include <it>rs16969968 </it>(heterogeneity p = 0.75). Though the power to filter out rs16969968 is reduced due to the difference in allele frequency in the two groups, the results nevertheless focus attention on a smaller group of SNPs that includes the non-synonymous SNP rs16969968, which retains a similar effect size (odds ratio) across both population samples.</p> <p>Conclusion</p> <p>Filtering out SNPs that demonstrate cross-population heterogeneity enriches for variants more likely to be important and causative. Our approach provides an important and effective tool to help interpret results from the many GWA studies now underway.</p

Vaginal lactoferrin in prevention of preterm birth in women with bacterial vaginosis

Objective: To evaluate use of vaginal lactoferrin in prevention of preterm birth (PTB) in women with first trimester bacterial vaginosis and prior spontaneous PTB.Methods: This is a retrospective cohort study of all consecutive singleton gestations with prior PTB, and first trimester diagnosis of bacterial vaginosis. Women who were found to have bacterial vaginosis were recommended lactoferrin 300 mg vaginal tablets daily for 21 days. The primary outcome was the incidence of PTB at less than 37 weeks of gestations. Outcomes were compared in women who received daily lactoferrin with those who did notResults: During the study period, 847 pregnant women with prior spontaneous PTB were screened for bacterial vaginosis. Of them, 193 were found to have bacterial vaginosis in the first trimester, with an overall incidence of 22.8%. Out of the 193 women, 125 met the inclusion criteria for the study and were analyzed. Sixty of the included women received vaginal lactoferrin, while 65 did not. Women who received supplementation with lactoferrin had a significantly lower rate of PTB < 37 weeks (25.0 versus 44.6%; p = .02), lower mean gestational age at delivery (37.7 ± 3.2 versus 35.9 ± 4.1 weeks; p = .01), and lower rate of admission for threatened PTL (45.0 versus 70.8%; p = .04). No between-group differences were noticed in the other outcomes, including chorioamnionitis, PPROM < 34 weeks, and neonatal outcomes. No cases of late miscarriage were reported in our cohort. No cases of adverse events were reported.Conclusion: Based on this small single-center retrospective study, supplementation with vaginal lactoferrin in women with first trimester bacterial vaginosis may be an option to reduce the risk of preterm delivery

Beneficial effects of curtailing immune susceptibility in an Alzheimer's disease model

Background Currently, there are no effective therapeutic options for Alzheimer's disease, the most common, multifactorial form of dementia, characterized by anomalous amyloid accumulation in the brain. Growing evidence points to neuroinflammation as a major promoter of AD. We have previously shown that the proinflammatory cytokine TNFSF10 fuels AD neuroinflammation, and that its immunoneutralization results in improved cognition in the 3xTg-AD mouse. Methods Here, we hypothesize that inflammatory hallmarks of AD might parallel with central and peripheral immune response dysfunction. To verify such hypothesis, we used a triple transgenic mouse model of AD. 3xTg-AD mice were treated for 12 months with an anti-TNFSF10 antibody, and thereafter immune/inflammatory markers including COX2, iNOS, IL-1 beta and TNF-alpha, CD3, GITR, and FoxP3 (markers of regulatory T cells) were measured in the spleen as well as in the hippocampus. Results Spleens displayed accumulation of amyloid-beta(1-42) (A beta(1-42)), as well as high expression of Treg cell markers FoxP3 and GITR, in parallel with the increased levels of inflammatory markers COX2, iNOS, IL-1 beta and TNF-alpha, and blunted IL-10 expression. Moreover, CD3 expression was increased in the hippocampus, consistently with FoxP3 and GITR. After chronic treatment of 3xTg-AD mice with an anti-TNFSF10 antibody, splenic FoxP3, GITR, and the above-mentioned inflammatory markers expression was restored to basal levels, while expression of IL-10 was increased. A similar picture was observed in the hippocampus. Such improvement of peripheral and CNS inflammatory/immune response was associated with decreased microglial activity in terms of TNF alpha production, as well as decreased expression of both amyloid and phosphorylated tau protein in the hippocampus of treated 3xTg-AD mice. Interestingly, we also reported an increased expression of both CD3 and FoxP3, in sections from human AD brain. Conclusions We suggest that neuroinflammation in the brain of 3xTg-AD mice triggered by TNFSF10 might result in a more general overshooting of the immune response. Treatment with an anti-TNFSF10 antibody blunted inflammatory processes both in the spleen and hippocampus. These data confirm the detrimental role of TNFSF10 in neurodegeneration, and corroborate the hypothesis of the anti-TNFSF10 strategy as a potential treatment to improve outcomes in AD

Exploring the phases of 3D artificial spin ice: From Coulomb phase to magnetic monopole crystal

Artificial spin-ices consist of lithographic arrays of single-domain magnetic nanowires organised into frustrated lattices. These geometries are usually two-dimensional, allowing a direct exploration of physics associated with frustration, topology and emergence. Recently, three-dimensional geometries have been realised, in which transport of emergent monopoles can be directly visualised upon the surface. Here we carry out an exploration of the three-dimensional artificial spin-ice phase diagram, whereby dipoles are placed within a diamond-bond lattice geometry. We find a rich phase diagram, consisting of a double-charged monopole crystal, a single-charged monopole crystal and conventional spin-ice with pinch points associated with a Coulomb phase. In our experimental demagnetised systems, broken symmetry forces formation of ferromagnetic stripes upon the surface, a configuration that forbids the formation of the lower energy double-charged monopole crystal. Instead, we observe crystallites of single magnetic charge, superimposed upon an ice background. The crystallites are found to form due to the intricate distribution of magnetic charge around a three-dimensional nanostructured vertex, which locally favours monopole formation. Our work suggests that engineered surface energetics can be used to tune the ground state of experimental three-dimensional ASI systems