Topologically Robust Transport of Photons in a Synthetic Gauge Field

Electronic transport in low dimensions through a disordered medium leads to localization. The addition of gauge fields to disordered media leads to fundamental changes in the transport properties. For example, chiral edge states can emerge in two-dimensional systems with a perpendicular magnetic field. Here, we implement a "synthetic'' gauge field for photons using silicon-on-insulator technology. By determining the distribution of transport properties, we confirm the localized transport in the bulk and the suppression of localization in edge states, using the "gold standard'' for localization studies. Our system provides a new platform to investigate transport properties in the presence of synthetic gauge fields, which is important both from the fundamental perspective of studying photonic transport and for applications in classical and quantum information processing.Comment: 4.5 pages, 3 figures and supplementary materia

High-cooperativity nanofiber laser

Cavity-free efficient coupling between emitters and guided modes is of great current interest for nonlinear quantum optics as well as efficient and scalable quantum information processing. In this work, we extend these activities to the coupling of organic dye molecules to a highly confined mode of a nanofiber, allowing mirrorless and low-threshold laser action in an effective mode volume of less than 100 femtoliters. We model this laser system based on semi-classical rate equations and present an analytic compact form of the laser output intensity. Despite the lack of a cavity structure, we achieve a coupling efficiency of the spontaneous emission to the waveguide mode of 0.07(0.01), in agreement with our calculations. In a further experiment, we also demonstrate the use of a plasmonic nanoparticle as a dispersive output coupler. Our laser architecture is promising for a number of applications in optofluidics and provides a fundamental model system for studying nonresonant feedback stimulated emission

Modification of Some Solution Techniques of Combinatorial Optimization Problems to Analyze the Transposition Cipher

In this paper we attempt to use a new direction in cryptanalysis of classical crypto systems. The new direction represented by considering some of classical crypto systems, like transposition cipher problem (TCP), as a combinatorial optimization problem (COP), then using the known solving methods of COP, with some modification, to cryptanalysis the TCP. In this work we investigate to use Branch and Bound (BAB) and one of swarm algorithms as a local search method. The main aim of the research presented in this paper is to investigate the use of some optimization methods in the fields of cryptanalysis and cryptographic function generation. These techniques were found to provide a successful method of automated cryptanalysis of a variety of the classical ciphers. Keywords: cryptography, cryptanalysis, Classical Ciphers, Transposition Cipher, Branch and Bound, Swarm Intelligence, Bees Algorithm

Anti-angiogenesis in cancer therapeutics: the magic bullet

Background: Angiogenesis is the formation of new vascular networks from preexisting ones through the migration and proliferation of differentiated endothelial cells. Available evidence suggests that while antiangiogenic therapy could inhibit tumour growth, the response to these agents is not sustained. The aim of this paper was to review the evidence for anti-angiogenic therapy in cancer therapeutics and the mechanisms and management of tumour resistance to antiangiogenic agents. We also explored the latest advances and challenges in this field. Main body of the abstract: MEDLINE and EMBASE databases were searched for publications on antiangiogenic therapy in cancer therapeutics from 1990 to 2020. Vascular endothelial growth factor (VEGF) is the master effector of the angiogenic response in cancers. Anti-angiogenic agents targeting the VEGF and HIF-α pathways include monoclonal antibodies to VEGF (e.g. bevacizumab), small-molecule tyrosine kinase inhibitors (TKIs) e.g. sorafenib, decoy receptor or VEGF trap e.g. aflibercept and VEGFR2 inhibitors (e.g. ramucirumab). These classes of drugs are vascular targeting which in many ways are advantageous over tumour cell targeting drugs. Their use leads to a reduction in the tumour blood supply and growth of the tumour blood vessels. Tumour resistance and cardiovascular toxicity are important challenges which limit the efficacy and long-term use of anti-angiogenic agents in cancer therapeutics. Tumour resistance can be overcome by dual anti-angiogenic therapy or combination with conventional chemotherapy and immunotherapy. Emerging nanoparticle-based therapy which can silence the expression of HIF-α gene expression by antisense oligonucleotides or miRNAs has been developed. Effective delivery platforms are required for such therapy. Short conclusion: Clinical surveillance is important for the early detection of tumour resistance and treatment failure using reliable biomarkers. It is hoped that the recent interest in mesenchymal cell-based and exosome-based nanoparticle delivery platforms will improve the cellular delivery of newer anti-angiogenics in cancer therapeutics

L’ATTEINTE RENALE CHEZ LES PATIENTS DREPANOCYTAIRES

Purpose: to estimate the frequency of renal abnormalities in patients with sickle cell disease and to assess the role of blood transfusion and treatment with hydroxyurea in sickle cell nephropathy prevention. Patients and methods: It’s a descriptive and cross-sectional study conducted hematology laboratory at Ibn Rochd University Hospital of Casablanca. The study was conducted during a period of one year (1 January to 31 December 2008). We included in this study patients with sickle cell disease all ages and gender confused. All patients underwent renal laboratory tests. Results: During the study period, 30 patients were collected. The average age of patients was 26 years. Eighteen patients (60%) had homozygous sickle cell disease SS and 12 had a heterozygous form (8 patients with SA (27%), 2 patients SC and 2 patients Sb). Abnormal renal laboratory tests were found in 14 patients (46,7%). Of the 14 patients with renal impairment, 7 have received blood transfusions (OR = 0.23 IC95% [0.03 to 1.50]). Eight of our patients were on hydroxyurea, 2 had abnormal renal function. (OR= 1  IC95% [0.10 to 8.90]) Conclusion: Sickle cell disease is associated with significant abnormalities of renal function. These abnormalities are more frequent in the SS genotype. We have not been able to prove the beneficial effect of the use of hydroxyurea or blood transfusion in the prevention of renal dysfunctions, perhaps due to the relatively small number of patients included in this study.But : Estimer la fréquence des anomalies biologiques rénales chez les patients atteints de drépanocytose et évaluer  le rôle de la transfusion sanguine et du traitement par hydroxyurée dans la prévention de la néphropathie drépanocytaire. Patients et méthodes : étude transversale de type descriptive réalisée au laboratoire d’hématologie du centre hospitalier universitaire Ibn Rochd de Casablanca. L’étude a été menée durant une période d’une année (du 1er Janvier au 31 Décembre 2008). Nous avons inclus dans cette étude tout patient drépanocytaire tout âge et tout sexe confondu. Tous les patients ont bénéficié d’un bilan biologique rénal. Résultats : Durant la période de l’étude, 30 patients ont été colligés. L’âge moyen des patients était 26 ans. Dix huit patients (60%) présentaient une drépanocytose homozygote SS et 12 avaient une drépanocytose hétérozygote (8 patients SA (27%), 2 patients SC et  2 patients Sbêta. Des anomalies du bilan biologique rénal ont été retrouvés chez 14 patients soit 46,7%. Sur ces 14 patients ayant une atteinte rénale, 7  seulement avaient déjà reçu des transfusions sanguines (OR=0,23 IC95%[0,03-1,50]). Huit de nos patients étaient sous hydroxyurée dont 2 avaient une anomalie de la fonction rénale. (OR=1 IC95%[0,10-8,90] ) Conclusion : La drépanocytose est associée à d'importantes anomalies de la fonction rénale.  Ces anomalies sont plus fréquentes dans le génotype SS. Nous n’avons pas pu prouver l’effet bénéfique de l'utilisation de l'hydroxyurée ou de la transfusion sanguine dans la prévention de l’atteinte rénale, peut-être en raison du nombre relativement faible des patients inclus dans ce travail

An outbreak of Glasser’s disease from two farms in Malaysia

Haemophilus parasuis is an endemic bacterial pathogen in pig farms worldwide. In this report, we investigated a suspected case of Glasser’s disease in 3-9 weeks old Landrace cross Duroc piglets from two pig farms. The farmers reported the case to the Veterinary Hospital of University Malaysia Kelantan, with the complaint of anorexia, depression and weakness. On physical examination, the piglets were found to be smaller in size and had rough hair coat. Clinical signs included swollen hock joint, labored abdominal breathing and tremors. Post-mortem evaluation of culled moribund piglets showed pneumonic lesions in the lung, polyarthritis of the hock joint, cerebral congestion, meningitis, renal cortical heamorrhage and polyserositis. Histo-pathological examination showed interstitial pneumonia with emphysema, encephalitis, encephalomalacia with gliosis and vacuolar degeneration of the hepatocytes. Bacteriological culture of swab samples from infected organs revealed the growth of satellitic small colonies on blood culture suggestive of H. parasuis. Ceftiofur injection (HIPRA, Malaysia, 3mg kg-1i.m), phenoxymethyl penicillin (Norvatis Animal Health, Australia at 200g T-1 of feed) and amoxicillin (Norvatis Animal Health at 15-30g 100L-1 of water) were effective in reducing morbidity and reversing clinical signs. Prompt diagnosis and treatment of Glasser’s disease in pig farms is paramount in order to curtail its menace and prevent serious economic losses

Clinical case of caseous lymphadenitis in a goat: case management

Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis (CLA) a contagious and infectious disease in small ruminants. This report describes a case of CLA in a Boer cross goat infected with Corynebacterium pseudotuberculosis. The manifestation of abscess in the superficial lymph node presented as a mass of approximately 5cm by 5cm in diameter at the base of the ear. The mass was solid and non-movable upon palpation. The mass was incised and the caseous material was aspirated and sent to the bacteriology laboratory where Corynebacterium pseudotuberculosis was isolated. The wound was cleaned and flushed with diluted chlorhexidine and iodine solutions daily. This procedure aids in the complete healing of the wound after a few weeks. However, the agent of the disease persists in the animal in its entire life and culling is recommended to prevent the spread of the disease in the herd

Multifractal analysis of the electronic states in the Fibonacci superlattice under weak electric fields

Influence of the weak electric field on the electronic structure of the Fibonacci superlattice is considered. The electric field produces a nonlinear dynamics of the energy spectrum of the aperiodic superlattice. Mechanism of the nonlinearity is explained in terms of energy levels anticrossings. The multifractal formalism is applied to investigate the effect of weak electric field on the statistical properties of electronic eigenfunctions. It is shown that the applied electric field does not remove the multifractal character of the electronic eigenfunctions, and that the singularity spectrum remains non-parabolic, however with a modified shape. Changes of the distances between energy levels of neighbouring eigenstates lead to the changes of the inverse participation ratio of the corresponding eigenfunctions in the weak electric field. It is demonstrated, that the local minima of the inverse participation ratio in the vicinity of the anticrossings correspond to discontinuity of the first derivative of the difference between marginal values of the singularity strength. Analysis of the generalized dimension as a function of the electric field shows that the electric field correlates spatial fluctuations of the neighbouring electronic eigenfunction amplitudes in the vicinity of anticrossings, and the nonlinear character of the scaling exponent confirms multifractality of the corresponding electronic eigenfunctions.Comment: 10 pages, 9 figure