Phase-locking and Pulse Generation in Multi-Frequency Brillouin Oscillator via Four Wave Mixing

There is an increasing demand for pulsed all-fibre lasers with gigahertz repetition rates for applications in telecommunications and metrology. The repetition rate of conventional passively mode-locked fibre lasers is fundamentally linked to the laser cavity length and is therefore typically ∼10-100â €...MHz, which is orders of magnitude lower than required. Cascading stimulated Brillouin scattering (SBS) in nonlinear resonators, however, enables the formation of Brillouin frequency combs (BFCs) with GHz line spacing, which is determined by the acoustic properties of the medium and is independent of the resonator length. Phase-locking of such combs therefore holds a promise to achieve gigahertz repetition rate lasers. The interplay of SBS and Kerr-nonlinear four-wave mixing (FWM) in nonlinear resonators has been previously investigated, yet the phase relationship of the waves has not been considered. Here, we present for the first time experimental and numerical results that demonstrate phase-locking of BFCs generated in a nonlinear waveguide cavity. Using real-time measurements we demonstrate stable 40â €...ps pulse trains with 8â €...GHz repetition rate based on a chalcogenide fibre cavity, without the aid of any additional phase-locking element. Detailed numerical modelling, which is in agreement with the experimental results, highlight the essential role of FWM in phase-locking of the BFC

Can oral infection be a risk factor for Alzheimer’s disease?

Alzheimer’s disease (AD) is a scourge of longevity that will drain enormous resources from public health budgets in the future. Currently, there is no diagnostic biomarker and/or treatment for this most common form of dementia in humans. AD can be of early familial-onset or sporadic with a late-onset. Apart from the two main hallmarks, amyloid-beta and neurofibrillary tangles, inflammation is a characteristic feature of AD neuropathology. Inflammation may be caused by a local central nervous system insult and/or by peripheral infections. Numerous microorganisms are suspected in AD brains ranging from bacteria (mainly oral and non-oral Treponema species), viruses (Herpes simplex type I) and yeasts (Candida species). A causal relationship between periodontal pathogens/non-oral Treponema species of bacteria has been proposed via the amyloid-beta and inflammatory links. Periodontitis constitutes a peripheral oral infection that can provide the brain with intact bacteria and virulence factors and inflammatory mediators due to daily, transient bacteraemias. If and when genetic risk factors meet environmental risk factors in the brain, disease is expressed, in which neurocognition may be impacted, leading to the development of dementia. To achieve the goal of finding a diagnostic biomarker and possible prophylactic treatment for AD, there is an initial need to solve the etiological puzzle contributing to its pathogenesis. This review therefore addresses oral infection as the plausible aetiology of late onset AD (LOAD)

The Role of Receptor for Advanced Glycation End Products in Airway Inflammation in CF and CF related Diabetes

Cystic Fibrosis (CF) is often accompanied by diabetes leading to worsening lung function, the reason for which is unclear. The receptor for advanced-glycation-end-products (RAGE) regulates immune responses and inflammation and has been linked to diabetes and possibly CF. We performed a pilot study to determine if CF and CF-related diabetes (CFRD) are associated with enhanced RAGE expression. Full length (fl)RAGE, soluble (s)RAGE, endogenous soluble (es)RAGE, S100A12 (enRAGE) and advanced-glycation-end-products (AGE) expression was assessed in serum, white blood cells and sputum of patients with CF; diabetes; CFRD and healthy subjects. Sputum enRAGE/sRAGE ratios were high in CF but particularly in CFRD which negatively correlated with % predicted FEV1. Serum AGE and AGE/sRAGE ratios were high in diabetics but not in CF. A complex, multifaceted approach was used to assess the role of RAGE and its ligands which is fundamental to determining their impact on airway inflammation. There is a clear association between RAGE activity in the airways of CF and CFRD patients that is not evident in the vascular compartment and correlates with lung function, in contrast to diabetes. This strongly suggests a role for RAGE in contributing to the inflammatory overdrive seen in CF and to a greater extent in CFRD

Single-atom imaging of fermions in a quantum-gas microscope

Single-atom-resolved detection in optical lattices using quantum-gas microscopes has enabled a new generation of experiments in the field of quantum simulation. Fluorescence imaging of individual atoms has so far been achieved for bosonic species with optical molasses cooling, whereas detection of fermionic alkaline atoms in optical lattices by this method has proven more challenging. Here we demonstrate single-site- and single-atom-resolved fluorescence imaging of fermionic potassium-40 atoms in a quantum-gas microscope setup using electromagnetically-induced-transparency cooling. We detected on average 1000 fluorescence photons from a single atom within 1.5s, while keeping it close to the vibrational ground state of the optical lattice. Our results will enable the study of strongly correlated fermionic quantum systems in optical lattices with resolution at the single-atom level, and give access to observables such as the local entropy distribution and individual defects in fermionic Mott insulators or anti-ferromagnetically ordered phases.Comment: 7 pages, 5 figures; Nature Physics, published online 13 July 201

Evaluating Complementary Therapies for Canine Osteoarthritis—Part II: A Homeopathic Combination Preparation (Zeel®)

A homeopathic combination preparation (HCP) for canine osteoarthritic pain was evaluated in a randomized, double-controlled and double-blinded clinical trial. Forty-four dogs with osteoarthritis (OA) that were randomly allocated into one of three groups completed the study. All dogs were fed test products or placebo for 8 weeks. The dogs were evaluated at the clinic four times, with 4-week intervals. Six different variables were assessed: veterinary-assessed mobility, two force plate variables, an owner-evaluated chronic pain index and pain and locomotion visual analogue scales (VASs). Intake of extra non-steroidal anti-inflammatory drugs was also evaluated. A Chi-squared test and a Mann–Whitney test were used to determine significant improvement between groups. When changed into dichotomous responses of ‘improved’ or ‘not improved’ three out of the six variables showed a significant difference (P = 0.016, P = 0.008, P = 0.039) in improved dogs per group, between the HCP group and the placebo group. The odds ratios were over one for the same variables. As extent of improvement in the variables from start to end of treatment, the HCP product was significantly more improved in four (P = 0.015, P = 0.028, P = 0.049, P = 0.020) of the six variables, compared with the placebo. Our results indicated that the HCP Zeel® was beneficial in alleviating chronic orthopedic pain in dogs although it was not as effective as carprofen

Osteoarticular Infection in Three Young Thoroughbred Horses Caused by a Novel Gram Negative Cocco-Bacillus

© 2020 Bernard J. Hudson et al. We describe three cases of osteoarticular infection (OAI) in young thoroughbred horses in which the causative organism was identified by MALDI-TOF as Kingella species. The pattern of OAI resembled that reported with Kingella infection in humans. Analysis by 16S rRNA PCR enabled construction of a phylogenetic tree that placed the isolates closer to Simonsiella and Alysiella species, rather than Kingella species. Average nucleotide identity (ANI) comparison between the new isolate and Kingella kingae and Alysiella crassa however revealed low probability that the new isolate belonged to either of these species. This preliminary analysis suggests the organism isolated is a previously unrecognised species

Comparative Population Genetics of the Immunity Gene, Relish: Is Adaptive Evolution Idiosyncratic?

The frequency of adaptive evolution acting on common loci in distant lineages remains an outstanding question in evolutionary biology. We asked whether the immunity factor, Relish, a gene with a history of directional selection in Drosophila simulans, shows evidence of a similar selective history in other Drosophila species. We found only weak evidence of recurrent adaptive protein evolution at the Relish locus in three sister species pairs, suggesting that this key component of the insect immune system has an idiosyncratic evolutionary history in Drosophila

Взаимосвязь ожирения и нарушений углеводного обмена с синдромом обструктивного апноэ во сне

Представлены литературные данные клинических исследований, в которых синдром обструктивного апноэ во сне (СОАС) рассматривается как фактор риска развития нарушений углеводного обмена, в том числе сахарного диабета 2−го типа. Анализируется взаимосвязь наиболее значимых факторов, влияющих на прогрессирование нарушений углеводного обмена у пациентов с СОАС. Приведен анализ данных о связи СОАС с диабетической автономной нейропатией и инсулинорезистентностью. Рассматривается возможность применения СРАР−терапии для коррекции метаболических нарушений у пациентов с сахарным диабетом.Представлено літературні дані клінічних досліджень, у яких синдром обструктивного апное під час сну (СОАС) розглянуто як фактор ризику розвитку порушень вуглеводного обміну, у тому числі цукрового діабету 2−го типу. Аналізується взаємозв'язок найбільш значущих факторів, що впливають на прогресування порушень вуглеводного обміну у пацієнтів із СОАС. Наведено аналіз даних про зв'язок СОАС із діабетичною автономною нейропатією та інсулінорезистентністю. Розглянуто можливість використання СРАР−терапії для корекції метаболічних порушень у пацієнтів із цукровим діабетом.Literature data about clinical trials, in which sleep apnea syndrome (SAS) is featured as a risk factor of carbohydrate metabolism disorders, including type 2 diabetes mellitus, are presented. Association of the most significant factors influencing the progress carbohydrate metabolism disorders in patients with SAS is analyzed. The data about the association of SAS and diabetic autonomous neuropathy and insulin resistance are featured. Possibility to use CPAP therapy for correction of metabolic disorders in patients with diabetes mellitus is discussed

First-principles design and subsequent synthesis of a material to search for the permanent electric dipole moment of the electron

We describe the first-principles design and subsequent synthesis of a new material with the specific functionalities required for a solid-state-based search for the permanent electric dipole moment of the electron. We show computationally that perovskite-structure europium barium titanate should exhibit the required large and pressure-dependent ferroelectric polarization, local magnetic moments, and absence of magnetic ordering even at liquid helium temperature. Subsequent synthesis and characterization of Eu$_{0.5}$Ba$_{0.5}$TiO$_3$ ceramics confirm the predicted desirable properties.Comment: Nature Materials, in pres