Possible scale invariant linear magnetoresistance in pyrochlore iridates Bi2Ir2O7

We report the observation of a linear magnetoresistance in single crystals and epitaxial thin films of the pyrochlore iridate Bi2Ir2O7. The linear magnetoresistance is positive and isotropic at low temperatures, without any sign of saturation up to 35 T. As temperature increases, the linear field dependence gradually evolves to a quadratic field dependence. The temperature and field dependence of magnetoresistance of Bi2Ir2O7 bears strikingly resemblance to the scale invariant magnetoresistance observed in the strange metal phase in high Tc cuprates. However, the residual resistivity of Bi2Ir2O7 is more than two orders of magnitude higher than the curpates. Our results suggest that the correlation between linear magnetoresistance and quantum fluctuations may exist beyond high temperature superconductors

COMPUTER SIMULATION OF UNIFIED SYNTHESIS AND ANALYSIS WITH RSSR-SC SPATIAL FIVE-BAR LINKAGE

ABSTRACT The basic tool of dimensional synthesis for spatial mechanisms is the spatial dyads and vector approach, but their processes are quite complicated and far from straightforward. Even when some mechanisms can be synthesized, the synthesis results cannot ensure that the synthesized mechanism has good kinematic characteristics and no interference between the links. A novel computer simulation approach of unified dimensional synthesis, interference check and analysis of the spatial mechanism is presented. Based on the geometry constraint and dimension-driving technique, using RSSR-SC five-bar spatial linkage, a simulation mechanism of path and motion generation is created for 8-approximate-point cases. By using an animation function, the interference between links is checked in a virtual reality, and some key dimensions of the simulation mechanism are modified To obtain better kinematic characteristics and noninterference. The results of computer simulation prove that the mechanism simulation approach is not only fairly quick and straightforward, but also advantageous from the viewpoint of accuracy and repeatability

Experimental study on mixed traffic flow of bicycles and pedestrians

The mixed flow of bicycles and pedestrians is frequently observed on bicycle-pedestrian-shared roads. Unfortunately, studies on dynamics of this kind of mixed flow are very limited. This paper reports an experimental study of this kind of mixed traffic flow with equal numbers of pedestrians and cyclists asked to walk/ride in a ring-shaped track. In the uni-/bi-directional flow scenarios, pedestrians and bicycles moved in the same/opposite direction. Under both scenarios, bicycles and pedestrians formed their own lanes. Pedestrians walked in the inner lane and cyclists rode in the outer lane. Widths of both the pedestrian lane and the bicycle lane were more uniform in bidirectional flow. The pedestrian flow rate is larger in the unidirectional flow scenario than in the bidirectional flow scenario. In contrast, at low densities, the bicycle flow rate is essentially the same under the two scenarios. When the density is large, the bicycle flow rate becomes larger in the unidirectional flow scenario. Comparing the two modes, pedestrian flow rate is smaller/larger than bicycle flow rate at small/large densities under both scenarios

Malignant epignathus teratoma

A baby boy who had a left facial mass detected on antenatal ultrasound was delivered by Caesarian section after foetal distress was detected. Imaging investigations by plain radiographs and MRI showed a large mass with calcifications, soft tissue, fat and fluid components. A total surgical excision was perfomed and histology examination showed teratoma with no malignant features. Two weeks postoperatively, there was rapid recurrence of the tumour with intracranial involvement and obstructive hydrocephalus shown on MRI. The tumour was inoperable at surgery and the baby subsequently died at 5 weeks of life. This case describes the clinical course and imaging features of a neonatal epignathus teratoma with malignant and aggressive features

Novel role for the innate immune receptor toll-like receptor 4 (TLR4) in the regulation of the wnt signaling pathway and photoreceptor apoptosis

Recent evidence has implicated innate immunity in regulating neuronal survival in the brain during stroke and other neurodegenerations. Photoreceptors are specialized light-detecting neurons in the retina that are essential for vision. In this study, we investigated the role of the innate immunity receptor TLR4 in photoreceptors. TLR4 activation by lipopolysaccharide (LPS) significantly reduced the survival of cultured mouse photoreceptors exposed to oxidative stress. With respect to mechanism, TLR4 suppressed Wnt signaling, decreased phosphorylation and activation of the Wnt receptor LRP6, and blocked the protective effect of the Wnt3a ligand. Paradoxically, TLR4 activation prior to oxidative injury protected photoreceptors, in a phenomenon known as preconditioning. Expression of TNFα and its receptors TNFR1 and TNFR2 decreased during preconditioning, and preconditioning was mimicked by TNFα antagonists, but was independent of Wnt signaling. Therefore, TLR4 is a novel regulator of photoreceptor survival that acts through the Wnt and TNFα pathways. © 2012 Yi et al

Self-assembly of Microcapsules via Colloidal Bond Hybridization and Anisotropy

Particles with directional interactions are promising building blocks for new functional materials and may serve as models for biological structures. Mutually attractive nanoparticles that are deformable due to flexible surface groups, for example, may spontaneously order themselves into strings, sheets and large vesicles. Furthermore, anisotropic colloids with attractive patches can self-assemble into open lattices and colloidal equivalents of molecules and micelles. However, model systems that combine mutual attraction, anisotropy, and deformability have---to the best of our knowledge---not been realized. Here, we synthesize colloidal particles that combine these three characteristics and obtain self-assembled microcapsules. We propose that mutual attraction and deformability induce directional interactions via colloidal bond hybridization. Our particles contain both mutually attractive and repulsive surface groups that are flexible. Analogous to the simplest chemical bond, where two isotropic orbitals hybridize into the molecular orbital of H2, these flexible groups redistribute upon binding. Via colloidal bond hybridization, isotropic spheres self-assemble into planar monolayers, while anisotropic snowman-like particles self-assemble into hollow monolayer microcapsules. A modest change of the building blocks thus results in a significant leap in the complexity of the self-assembled structures. In other words, these relatively simple building blocks self-assemble into dramatically more complex structures than similar particles that are isotropic or non-deformable

Subcellular localization of MC4R with ADCY3 at neuronal primary cilia underlies a common pathway for genetic predisposition to obesity.

Most monogenic cases of obesity in humans have been linked to mutations in genes encoding members of the leptin-melanocortin pathway. Specifically, mutations in MC4R, the melanocortin-4 receptor gene, account for 3-5% of all severe obesity cases in humans1-3. Recently, ADCY3 (adenylyl cyclase 3) gene mutations have been implicated in obesity4,5. ADCY3 localizes to the primary cilia of neurons 6 , organelles that function as hubs for select signaling pathways. Mutations that disrupt the functions of primary cilia cause ciliopathies, rare recessive pleiotropic diseases in which obesity is a cardinal manifestation 7 . We demonstrate that MC4R colocalizes with ADCY3 at the primary cilia of a subset of hypothalamic neurons, that obesity-associated MC4R mutations impair ciliary localization and that inhibition of adenylyl cyclase signaling at the primary cilia of these neurons increases body weight. These data suggest that impaired signaling from the primary cilia of MC4R neurons is a common pathway underlying genetic causes of obesity in humans

Iron content in forage sorghum (Sorghum bicolor (L.) Moench) measured on different slit widths with atomic absorption spectrometry

Our objective was to know the right slit width for iron (Fe) concentration of forage sorghum, sorghum hybrid (Sorghum bicolor (L.) Moench), and also to discern which water treatment sludge (WTS) were good for ruminant's health with the feeding sorghum on the present study. The present experiment was carried out on a randomized block design with four treatments; Control, alum sludge compost, alum sludge + NPK (nitrogen, phosphorus, potassium fertilizers), alum sludge compost + NPK (nitrogen, phosphorus, potassium fertilizers). Sorghum hybrid was harvested, and iron content of it was analyzed with an atomic absorption spectrophotometer on background correction (BGC) mode. In order to analyze the iron (Fe) content of the sorghum with the spectrophotometer, three different slit widths conditions were used; 0.15, 0.20 and 0.25 nm. Absorbance and background values were obtained during the Fe analyses with the apparatus. When the background value is small, it is preferred for some trace metals’ analyses. Both (AM/BS) ratio (mean of the absorbance values<AM> to the standard deviation of back ground values<BS>) and (AS<standard deviation of the absorbance values>/BS) ratio, were larger on 0.25 nm slit than those on 0.15 and 0.20 nm slit, and, from our experiment, the condition seemed better on the 0.25 nm slit for the iron analysis with the spectrophotometer. Therefore, the sorghum hybrid grown on (Alum+NPK) and on (Compost only) might be dangerous for ruminants because of their higher values than 200 mg Fe/kg DM (dry matter).Key words: Absorbance, alum sludge, atomic absorption spectrophotometer, background, forage sorghum hybrid, iron, slit