Aharonov-Bohm oscillations effectively demonstrate coherent, ballistic transport in mesoscopic rings and tubes. In three-dimensional topological insulator nanowires, they can be used to not only characterize surface states but also to test predictions of unique topological behaviour. Here we report measurements of Aharonov-Bohm oscillations in (Bi 1.33 Sb 0.67 )Se 3 that demonstrate salient features of topological nanowires. By fabricating quasi-ballistic three-dimensional topological insulator nanowire devices that are gate-tunable through the Dirac point, we are able to observe alternations of conductance maxima and minima with gate voltage. Near the Dirac point, we observe conductance minima for zero magnetic flux through the nanowire and corresponding maxima (having magnitudes of almost a conductance quantum) at magnetic flux equal to half a flux quantum; this is consistent with the presence of a low-energy topological mode. The observation of this mode is a necessary step towards utilizing topological properties at the nanoscale in post-CMOS applications.

Systemic inflammatory factors are inconsistently associated with the pathogenesis of chronic obstructive pulmonary disease (COPD). We conducted a systematic review and meta-analysis to summarize the evidence supporting the association between systemic inflammation and the risk of COPD. Pertinent studies were retrieved from PubMed, EmBase, and the Cochrane Library until April 2015. A random-effects model was used to process the data, and the analysis was further stratified by factors affecting these associations. Sensitivity analyses for publication bias were performed. We included 24 observational studies reporting data on 10,677 COPD patients and 28,660 controls. Overall, we noted that COPD was associated with elevated serum CRP (SMD: 1.21; 95%CI: 0.92–1.50; P < 0.001), leukocytes (SMD: 1.07; 95%: 0.25–1.88; P = 0.010), IL-6 (SMD: 0.90; 95%CI: 0.48–1.31; P < 0.001), IL-8 (SMD: 2.34; 95%CI: 0.69–4.00; P = 0.006), and fibrinogen levels (SMD: 0.87; 95%CI: 0.44–1.31; P < 0.001) when compared with control. However, COPD was not significantly associated with TNF-α levels when compared with control (SMD: 0.60; 95%CI: -0.46 to 1.67; P = 0.266). Our findings suggested that COPD was associated with elevated serum CRP, leukocytes, IL-6, IL-8, and fibrinogen, without any significant relationship with TNF-α.

The diamondback moth, Plutella xylostella is a cosmopolitan pest that has evolved resistance to all classes of insecticide, and costs the world economy an estimated US $4-5 billion annually. We analyse patterns of variation among 532 P. xylostella genomes, representing a worldwide sample of 114 populations. We find evidence that suggests South America is the geographical area of origin of this species, challenging earlier hypotheses of an Old-World origin. Our analysis indicates that Plutella xylostella has experienced three major expansions across the world, mainly facilitated by European colonization and global trade. We identify genomic signatures of selection in genes related to metabolic and signaling pathways that could be evidence of environmental adaptation. This evolutionary history of P. xylostella provides insights into transoceanic movements that have enabled it to become a worldwide pest.

orthorhombic-phase molybdenum trioxide (α-MoO 3), the permittivity has opposite signs along different axes, giving rise to even more exotic physics that provides avenues to novel polaritonic applications such as subdiffraction imaging [6] and super-Planckian thermal emission. [4] Several recent works have demonstrated that α-MoO 3 , a natural van der Waals material with full anisotropy along three Cartesian axes, supports hyperbolic phonon polaritons (HPhPs) in the mid-infrared (MIR) range with many desirable properties such as in-plane hyperbolicity, deep-subwavelength light confinement, and topological transitions, making it arguably one of the most promising polaritonic materials. [8-12] In fact, α-MoO 3 has multiple RBs ranging from MIR to far-infrared (FIR), with different kinds of dispersions in each of them. However, previous studies have not fully revealed the intriguing properties of HPhPs in α-MoO 3 since they only involved two RBs in MIR. Technically, the difficulty is that the commonly employed method for visualizing SPhPs-scattering-type scanning near-field optical microscopy (s-SNOM)-is generally limited to the MIR (typically >100 meV) and the terahertz range (<10 meV), [13,14] leaving a gap covering FIR due to the lack of continuous-wave laser sources. A very recent work [10] combined s-SNOM with photoinduced force microscopy to extend the Hyperbolic phonon polaritons (HPhPs) in orthorhombic-phase molybdenum trioxide (α-MoO 3) show in-plane hyperbolicity, great wavelength compression, and ultralong lifetime, therefore holding great potential in nanophotonic applications. However, its polaritonic response in the far-infrared (FIR) range remains unexplored due to challenges in experimental characterization. Here, monochromated electron energy loss spectroscopy (EELS) in a scanning transmission electron microscope (STEM) is used to probe HPhPs in α-MoO 3 in both mid-infrared (MIR) and FIR frequencies and correlate their behaviors with microstructures and orientations. It is found that low structural symmetry leads to various phonon modes and multiple Reststrahlen bands (RBs) over a broad spectral range (over 70 meV) and in different directions (55-63 meV and 119-125 meV along the b-axis, 68-106 meV along the c-axis, and 101-121 meV along the a-axis). These HPhPs can be selectively excited by controlling the direction of swift electrons. These findings provide new opportunities in nanophotonic and optoelectronic applications, such as directed light propagation, hyperlenses, and heat transfer. Surface phonon polaritons (SPhPs) have great potential in achieving low-loss nanophotonic applications such as waveguiding, superlensing, enhanced optical forcing, enhanced energy transfer and sensing. [1-4] In the frequency band between transverse optical (TO) and longitudinal optical (LO) frequencies (termed the reststrahlen band (RB)), the real part of permittivity becomes negative and sustains SPhPs. In hyperbolic media such as hexagonal boron nitride (h-BN) [4-7] and

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