On asymmetric generalized solitary gravity-capillary waves in finite depth

Generalized solitary waves propagating at the surface of a fluid of finite depth are considered. The fluid is assumed to be inviscid and incompressible and the flow to be irrotational. Both the effects of gravity and surface tension are included. It is shown that in addition to the classical symmetric waves, there are new asymmetric solutions. These new branches of solutions bifurcate from the branches of symmetric waves. The detailed bifurcation diagrams as well as typical wave profiles are presented.

Talbot Effect for Exciton Polaritons

We demonstrate, experimentally and theoretically, a Talbot effect for hybrid light-matter waves-an exciton-polariton condensate formed in a semiconductor microcavity with embedded quantum wells. The characteristic "Talbot carpet" is produced by loading the exciton-polariton condensate into a microstructured one-dimensional periodic array of mesa traps, which creates an array of phase-locked sources for coherent polariton flow in the plane of the quantum wells. The spatial distribution of the Talbot fringes outside the mesas mimics the near-field diffraction of a monochromatic wave on a periodic amplitude and phase grating with the grating period comparable to the wavelength. Despite the lossy nature of the polariton system, the Talbot pattern persists for distances exceeding the size of the mesas by an order of magnitude. Thus, our experiment demonstrates efficient shaping of the two-dimensional flow of coherent exciton polaritons by a one-dimensional "flat lens."

Diagnosis of latent tuberculosis by ELISPOT assay and tuberculin skin test

OBJECTIVE

To determine the prevalence of latent tuberculosis infection (LTBI) in college students.

PATIENTS AND METHODS

Four hundred and twenty newly admitted college students were enrolled. The Enzyme-Linked ImmunoSpot assay (ELISPOT) was used. Overall, 171 students with ELISPOT assay+/TST+ were monitored for three years to detect active TB disease.

RESULTS

The overall positive rate of ELISPOT assay was 40.7% among TST+ students. The ELISPOT positive rates were 36.9%, 45.4%, and 64.3% in groups of TST induration of 10-14mm, 15-20mm, and ≥20mm, respectively, with a significant difference (χ(2)=10.136, P<0.01) but no significant difference between BCG scar and no scar (41.2% vs. 38.8%; P>0.05). None of the 171 untreated students contracted active TB within the three-year monitoring period.

CONCLUSION

The LTBI rate might be overestimated by TST compared with interferon-γ release assays. On the basis of a close monitoring, few students developed active TB despite a positive result to the TST and ELISPOT assay.

Fibrin Glue Injections: A Minimally Invasive and Cost-Effective Treatment for Post-Renal Transplant Lymphoceles and Lymph Fistulas

Pelvic lymphoceles/lymph fistulas are commonly observed after kidney allotransplantation, especially when the kidney is placed in a retroperitoneal position. While the majority are <5 cm in diameter and resolve without intervention, some may continue to enlarge, and cause local or systemic symptoms or graft dysfunction. Among 1662 recipients of both living and deceased donor kidney transplants between January 2003 and July 2014, we found 46 (2.7%) patients with symptomatic lymphoceles requiring intervention. We studied the clinical outcomes and charges for three treatment modalities including open surgical drainage (22), laparoscopic surgical drainage (11), and percutaneous fibrin glue injections into the drained lymphocele cavity (13). The patient demographics and clinical characteristics were comparable for each treatment group, although maintenance immunosuppressive drugs differed by era. We found fibrin glue injections resulted in significantly lower (p = 0.04) rates of recurrence (1; 7.7%) than either laparoscopic (6; 54%) or open surgical drainage (6; 27.3%). In addition, fibrin glue injections generated significantly (p < 0.001) lower median ($4559) charges compared to either laparoscopic ($26,330) or open surgical drainage ($23,758). Fibrin glue treatment has the advantage of being an outpatient procedure, performed with the patient under local anesthesia, and does not incur the expense of an operative procedure or hospital admission associated with laparoscopic or open surgery.

Observation of non-Hermitian degeneracies in a chaotic exciton-polariton billiard

Exciton-polaritons are hybrid light-matter quasiparticles formed by strongly interacting photons and excitons (electron-hole pairs) in semiconductor microcavities. They have emerged as a robust solid-state platform for next-generation optoelectronic applications as well as for fundamental studies of quantum many-body physics. Importantly, exciton-polaritons are a profoundly open (that is, non-Hermitian) quantum system, which requires constant pumping of energy and continuously decays, releasing coherent radiation. Thus, the exciton-polaritons always exist in a balanced potential landscape of gain and loss. However, the inherent non-Hermitian nature of this potential has so far been largely ignored in exciton-polariton physics. Here we demonstrate that non-Hermiticity dramatically modifies the structure of modes and spectral degeneracies in exciton-polariton systems, and, therefore, will affect their quantum transport, localization and dynamical properties. Using a spatially structured optical pump, we create a chaotic exciton-polariton billiard--a two-dimensional area enclosed by a curved potential barrier. Eigenmodes of this billiard exhibit multiple non-Hermitian spectral degeneracies, known as exceptional points. Such points can cause remarkable wave phenomena, such as unidirectional transport, anomalous lasing/absorption and chiral modes. By varying parameters of the billiard, we observe crossing and anti-crossing of energy levels and reveal the non-trivial topological modal structure exclusive to non-Hermitian systems. We also observe mode switching and a topological Berry phase for a parameter loop encircling the exceptional point. Our findings pave the way to studies of non-Hermitian quantum dynamics of exciton-polaritons, which may uncover novel operating principles for polariton-based devices.

Spontaneous burrowing behavior as an outcome measure of the global impact of chronic pain in preclinical models of arthritis

Aims

Arthritis is the leading cause of chronic pain in European adults (painineurope.com). Arthritis-induced chronic pain is a major clinical problem that is frequently inadequately treated by current analgesics and results in significant reduction in the patient’s quality of life. Outcome measures used in pain research to assess injury-induced pain-like behaviours in preclinical models are often dependent on the assessment of withdrawal reflexes, typically evoked by mechanical or thermal stimuli.Advances inpre-dictive validity may be improved by assessing the global impact of pain and the reinstatement of innate behaviours suppressed by injury. Burrowing, an indicator of the global “wellbeing” of the animal can be objectively measured. We aimed to assess the impact of several preclinical modelsof arthritis onburrowing behaviour in mice.

Methods

The collagen antibody-induced arthritis (CAIA) pre-clinical model of rheumatoid arthritis, the complete Freund’s adjuvant (CFA), monosodium iodoacetate (MIA) and partial medial menisectomy (MMT) preclinical models of osteoarthritis were assessed in female and/or male C57/Black6J adult mice, comparing to control (salineorsham-operated) and naïve animals. Mechanical hypersensitivity using von Frey filaments and spontaneous burrowing behaviour were assessed over60days (CAIA), 14days (CFA), 28 days (MIA) and up to 200 days (MMT).

Results

We show the development of mechanical hypersen-sitivity in all preclinical models of arthritis, whereas spontaneous burrowing behaviour was altered differently between the preclin-ical models. A deficit in burrowing behaviour was observed in the preclinical models of osteoarthritis and a gain in burrowing behaviour noted in the preclinical model of rheumatoid arthritis, with no effect seen in the CFA model.

Conclusions

Burrowing behaviour appears more sensitive to detecting variation in preclinical models of arthritis when compared to mechanical hypersensitivity. Burrowing behaviour can detect both gain and deficits in the behaviour, which differs between preclinical models of rheumatoid and osteoarthritis.