We theoretically demonstrate for the first time that a single free electron in circular or spiral motion emits twisted photons carrying well-defined orbital angular momentum along the axis of the ...electron circulation, in adding to spin angular momentum. We show that, when the electron velocity is relativistic, the radiation field contains harmonic components and the photons of lth harmonic carry lℏ total angular momentum for each. This work indicates that twisted photons are naturally emitted by free electrons and are more ubiquitous in laboratories and in nature than ever thought.
Ammonia is one of the most hazardous substance and highly toxic to human health when inhaled above the moderate level. Sensing ammonia is one most challenging task at low temperature level and room ...temperature. ZnO and Al-doped ZnO nanostructures were successfully synthesized by sol–gel method, and their structural, optical, morphological, and gas sensing properties were investigated. Field-emission scanning electron microscopy revealed that the ZnO nanorods transformed into particles upon incorporation of Al. Transmission electron microscopy and high-resolution transmission electron microscopy confirmed that both the ZnO nanorods and Al-doped ZnO nanoparticles were crystalline. Fourier transform infrared spectroscopy analysis indicated the presence of Zn–O and Al–O in the nanostructures. Energy-dispersive X-ray spectroscopy revealed the presence of Al in the Al-doped ZnO materials. The ammonia gas sensing analysis revealed that the Al-doped ZnO nanoparticles displayed a higher response than the ZnO nanorods. Moreover, among the doped samples, that containing 6 wt% Al dopant exhibited the highest response of 350 when exposed to 100 ppm ammonia gas. The higher sensing efficiency of the Al-doped ZnO nanostructures was attributed to changes in structural defects in Al-doped ZnO, as confirmed by X-ray photoelectron spectroscopy analysis.
•ZnO nanorods and AZO nanoparticle were synthesized.•AZO nanoparticle had wider optical absorption region than ZnO nanorods.•Sensing response of ammonia was enhanced by the incorporation of Al.•Al-doped ZnO (6%) showed maximum response of 350 for 100 ppm at room temperature.
MicroRNAs are small, non-coding RNAs that influence gene regulatory networks by post-transcriptional regulation of specific messenger RNA targets. MicroRNA expression is dysregulated in human ...malignancies, frequently leading to loss of expression of certain microRNAs. We report that expression of hsa-miR-342, a microRNA encoded in an intron of the gene EVL, is commonly suppressed in human colorectal cancer. The expression of hsa-miR-342 is coordinated with that of EVL and our results indicate that the mechanism of silencing is CpG island methylation upstream of EVL. We found methylation at the EVL/hsa-miR-342 locus in 86% of colorectal adenocarcinomas and in 67% of adenomas, indicating that it is an early event in colorectal carcinogenesis. In addition, we observed a higher frequency of methylation (56%) in histologically normal colorectal mucosa from individuals with concurrent cancer compared to mucosa from individuals without colorectal cancer (12%), suggesting the existence of a 'field defect' involving methylated EVL/hsa-miR-342. Furthermore, reconstitution of hsa-miR-342 in the colorectal cancer cell line HT-29 induced apoptosis, suggesting that this microRNA could function as a proapoptotic tumor suppressor. In aggregate, these results support a novel mechanism for silencing intronic microRNAs in cancer by epigenetic alterations of cognate host genes.
Objective
Recent epidemiologic studies worldwide have documented a rise in prevalence rates for autism spectrum disorders (ASD). Broadening of diagnostic criteria for ASD may be a major contributor ...to the rise in prevalence, particularly if superimposed on an underlying continuous distribution of autistic traits. This study sought to determine the nature of the population distribution of autistic traits using a quantitative trait measure in a large national population sample of children.
Method
The Japanese version of the Social Responsiveness Scale (SRS) was completed by parents on a nationally representative sample of 22 529 children, age 6–15.
Results
Social Responsiveness Scale scores exhibited a skewed normal distribution in the Japanese population with a single‐factor structure and no significant relation to IQ within the normal intellectual range. There was no evidence of a natural ‘cutoff’ that would differentiate populations of categorically affected children from unaffected children.
Conclusion
This study provides evidence of the continuous nature of autistic symptoms measured by the SRS, a validated quantitative trait measure. The findings reveal how paradigms for diagnosis that rest on arbitrarily imposed categorical cutoffs can result in substantial variation in prevalence estimation, especially when measurements used for case assignment are not standardized for a given population.
We have investigated the physical origin of anomalous in-plane thermal expansion (TE) anisotropy leading to invar-like behavior and negative TE in nanostructured NiTi sheets manufactured via severe ...cold-rolling. The roles of grain size (GS), crystallographic texture, thermally-induced phase transformation, and intrinsic (lattice level) TE of austenite (B2) and martensite (B19′) phases on the macroscopic TE behavior are addressed. It is shown that by controlling the cold-rolling thickness reduction and heat-treatment temperature the coefficient of thermal expansion (CTE) can be controlled in a wide range from positive (α ∼ 2.1 × 10−5 K−1) to negative (α ∼ −1.1 × 10−5 K−1) via in-plane anisotropy of TE. A very small CTE of α ∼ −5.3 × 10−7 K−1 (invar-like behavior) in a wide temperature window of 230 K (353–123 K) is obtained at an angle of 33.5° to the rolling direction (RD) of the severely cold-rolled sheet. TEM and XRD studies show that the microstructure underlying such anomalous TE behavior consists of a mixture of B2 nano-grains and retained/residual deformation-induced martensite and that the observed anomalous TE anisotropy is due to the intrinsic anisotropic TE of residual martensite. The invar-like behavior is the result of the cancellation of the positive TE of austenite phase with the negative TE of residual martensite along 33.5° to the RD. A simple rule of mixture model incorporating the intrinsic TE of B2 and B19′ lattices and the texture coefficients of the sample is proposed which successfully captures the anomalous in-plane TE anisotropy. The discovery of high dimensional stability over a wide temperature window along with temperature insensitive non-hysteretic linear superelasticity of the severely-deformed NiTi opens up a new route for designing stable SMAs for applications in ragged environments.
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IgG4-related disease is characterized by histologic fibrosis with IgG4-positive plasma cell infiltration. Our study evaluated MR imaging features of IgG4-related disease in the head and neck and ...brain. Images from 15 patients were retrospectively evaluated for the location, signal intensity, and enhancement patterns of lesions. Lacrimal gland enlargement was observed in 8 cases. Other lesions included orbital pseudotumor in 5, pituitary enlargement in 5, and cranial nerve enlargement in 7; the infraorbital nerve was involved in 4. All lesions were hypointense on T2-weighted images, which is typical for IgG4-related lesions. Multiple sites were involved in the head and neck and brain in 11 patients. The diagnosis of IgG4-related disease should be considered in a patient presenting with T2 hypointense lacrimal gland, pituitary, or cranial nerve enlargement, or a T2 hypointense orbital mass, especially if multiple sites in the head and neck are involved in the presence of elevated serum IgG4.
This article provides an overview of phase-contrast and time-spatial labeling inversion pulse MR imaging techniques to assess CSF movement in the CNS under normal and pathophysiologic situations. ...Phase-contrast can quantitatively measure stroke volume in selected regions, notably the aqueduct of Sylvius, synchronized to the heartbeat. Judicious fine-tuning of the technique is needed to achieve maximal temporal resolution, and it has limited visualization of CSF motion in many CNS regions. Phase-contrast is frequently used to evaluate those patients with suspected normal pressure hydrocephalus and a Chiari I malformation. Correlation with successful treatment outcome has been problematic. Time-spatial labeling inversion pulse, with a high signal-to-noise ratio, assesses linear and turbulent motion of CSF anywhere in the CNS. Time-spatial labeling inversion pulse can qualitatively visualize whether CSF flows between 2 compartments and determine whether there is flow through the aqueduct of Sylvius or a new surgically created stoma. Cine images reveal CSF linear and turbulent flow patterns.
Using high-energy X-ray diffraction we examined the atomic structure in bulk metallic glass samples which underwent severe plastic deformation by the high-pressure torsion (HPT) technique. We ...obtained the atomic pair distribution function (PDF) and determined the changes in the PDFs due to deformation. The observed changes in the PDF clearly show structural disordering, which suggests structural rejuvenation by heavy deformation. However, the changes cannot be explained simply in terms of creating excess free volume, and they indicate that much more extensive atomic rearrangements take place as a consequence of deformation. Also, we suggest that the observed structural change may well be an outcome of local heating due to deformation and may not directly provide the knowledge of the atomistic mechanism of strain localization.
We examined the sequence variation of mitochondrial DNA control region and cytochrome b gene of the house mouse (Mus musculus sensu lato) drawn from ca. 200 localities, with 286 new samples drawn ...primarily from previously unsampled portions of their Eurasian distribution and with the objective of further clarifying evolutionary episodes of this species before and after the onset of human-mediated long-distance dispersals. Phylogenetic analysis of the expanded data detected five equally distinct clades, with geographic ranges of northern Eurasia (musculus, MUS), India and Southeast Asia (castaneus, CAS), Nepal (unspecified, NEP), western Europe (domesticus, DOM) and Yemen (gentilulus). Our results confirm previous suggestions of Southwestern Asia as the likely place of origin of M. musculus and the region of Iran, Afghanistan, Pakistan, and northern India, specifically as the ancestral homeland of CAS. The divergence of the subspecies lineages and of internal sublineage differentiation within CAS were estimated to be 0.37-0.47 and 0.14-0.23 million years ago (mya), respectively, assuming a split of M. musculus and Mus spretus at 1.7 mya. Of the four CAS sublineages detected, only one extends to eastern parts of India, Southeast Asia, Indonesia, Philippines, South China, Northeast China, Primorye, Sakhalin and Japan, implying a dramatic range expansion of CAS out of its homeland during an evolutionary short time, perhaps associated with the spread of agricultural practices. Multiple and non-coincident eastward dispersal events of MUS sublineages to distant geographic areas, such as northern China, Russia and Korea, are inferred, with the possibility of several different routes.
► Combination of deformation modes is effective for the enhancement of uniform elongation. ► The alloys deformed by slip and twinning can be designed with the Mo equivalency. ► The deformation is ...heterogeneous among the grains and the twins are not seen in some of the grains. ► The segregation of alloying elements affects the heterogeneous deformation.
A combination of different deformation modes, namely, dislocation slip and {3
3
2}〈1
1
3〉 twinning was found to be effective for achieving high yield strength and large uniform elongation in the β type Ti–15Mo–5Zr and Ti–10Mo–2Fe alloys in the as-solution treated condition, where the Mo equivalency was designed to be between 15.3 and 18.7
mass%. The high yield strength was caused mainly by the slip, and the large uniform elongation was caused by the twinning through significant work hardening. The change in the work hardening rate with strain correlated well with the formation of mechanical twins. The deformation was heterogeneous among the grains and the twins were not seen in some of the grains even after the tensile fracture. This heterogeneity was discussed based on the effects of the grain orientation and the segregation of alloying elements.
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