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1.
Opt Lett ; 47(15): 3652-3655, 2022 Aug 01.
Article in English | MEDLINE | ID: mdl-35913281

ABSTRACT

We demonstrate the existence of breathing dissipative light bullets in a birefringent optical resonator filled with Kerr media. The propagation of light inside the cavity for each polarized component, which is coupled by cross-phase modulation, is described by the coupled Lugiato-Lefever equations. The space-time dynamics of breathing light bullets are described using Stokes parameters and frequency spectra.

2.
Phys Rev Lett ; 126(15): 153902, 2021 Apr 16.
Article in English | MEDLINE | ID: mdl-33929226

ABSTRACT

We report the existence of stable dissipative light bullets in Kerr cavities. These three-dimensional (3D) localized structures consist of either an isolated light bullet (LB), bound together, or could occur in clusters forming well-defined 3D patterns. They can be seen as stationary states in the reference frame moving with the group velocity of light within the cavity. The number of LBs and their distribution in 3D settings are determined by the initial conditions, while their maximum peak power remains constant for a fixed value of the system parameters. Their bifurcation diagram allows us to explain this phenomenon as a manifestation of homoclinic snaking for dissipative light bullets. However, when the strength of the injected beam is increased, LBs lose their stability and the cavity field exhibits giant, short-living 3D pulses. The statistical characterization of pulse amplitude reveals a long tail probability distribution, indicating the occurrence of extreme events, often called rogue waves.

3.
Haemophilia ; 24(5): e328-e337, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29902361

ABSTRACT

INTRODUCTION: Immune tolerance induction (ITI) was the primary therapeutic approach to eradicate inhibitors in haemophilia patients. Several large ITI registries had been reported, but successful predictors of ITI outcome are still debated. No reports are available on large ITI studies in non-caucasian countries. AIM: We designed a retrospective cohort study of ITI in Japanese haemophilia patients with inhibitor. METHODS: Retrospective data were collected from 155 haemophilia (H)A (140 severe-type) and 7 HB (7 severe-type) patients treated at 45 institutions. ITI outcome was centrally reviewed. We defined "success" as undetectable inhibitor after 2 consecutive measurements. RESULTS: The ITI success rate was 71.2% for HA and 83.3% for HB. Cumulated success rates for HA achieving 50% and 75% were 0.7 and 2 years after treatment, respectively. Significant successful predictors in HA were low-responding inhibitors compared to high-responding inhibitors, shorter time to the start of ITI, and lower historical and treatment peak titres of inhibitor. Dose regimen (high dose; ≥90 IU/kg every day, low dose; ≤75 IU/kg, 3 d/wk) and the type of therapeutic product did not affect outcomes. The success rate of salvage ITI using von Willebrand factor-containing factor VIII was 50% (n = 6/12), and patient age at the start of salvage ITI was a significant predictor. The inhibitor recurred in 6 HA cases (3.9%). CONCLUSION: The results provided potentially important information for improving future success rates for ITI in inhibitor patients.


Subject(s)
Hemophilia A/immunology , Immune Tolerance/immunology , Child, Preschool , Cohort Studies , Female , Hemophilia A/drug therapy , Humans , Japan , Male , Retrospective Studies , Treatment Outcome
4.
Opt Express ; 25(5): 4714-4719, 2017 Mar 06.
Article in English | MEDLINE | ID: mdl-28380742

ABSTRACT

We investigate the spatio-temporal dynamics of a ring cavity filled with a non-instantaneous Kerr medium and driven by a coherent injected beam. We show the existence of a stable mixed-mode solution that can be either extended or localized in space. The mixed-mode solutions are obtained in a regime where Turing instability (often called modulational instability) interacts with self-pulsing phenomenon (Andronov-Hopf bifurcation). We numerically describe the transition from stationary inhomogeneous solutions to a branch of mixed-mode solutions. We characterize this transition by constructing the bifurcation diagram associated with these solutions. Finally, we show stable localized mixed-mode solutions, which consist of time-periodic oscillations that are localized in space.

5.
Opt Lett ; 42(6): 1063-1066, 2017 Mar 15.
Article in English | MEDLINE | ID: mdl-28295092

ABSTRACT

Complex spatiotemporal dynamics have been a subject of recent experimental investigations in optical frequency comb microresonators and in driven fiber cavities with Kerr-type media. We show that this complex behavior has a spatiotemporal chaotic nature. We determine numerically the Lyapunov spectra, allowing us to characterize different dynamical behavior occurring in these simple devices. The Yorke-Kaplan dimension is used as an order parameter to characterize the bifurcation diagram. We identify a wide regime of parameters where the system exhibits a coexistence between the spatiotemporal chaos, the oscillatory localized structure, and the homogeneous steady state. The destabilization of an oscillatory localized state through radiation of counter-propagating fronts between the homogeneous and the spatiotemporal chaotic states is analyzed. To characterize better the spatiotemporal chaos, we estimate the front speed as a function of the pump intensity.

6.
Haemophilia ; 23(1): 59-66, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27480904

ABSTRACT

INTRODUCTION: MC710, a 1:10 protein weight ratio mixture of plasma-derived activated factor VII (FVIIa) and factor X (FX), is a novel bypassing agent for haemostasis in haemophilia patients with inhibitors. We evaluated the haemostatic efficacy and safety of one to two administrations of MC710 in 21 joint, muscle, and subcutaneous bleeding episodes in 14 male patients, in a multi-centre, open-label, non-randomized clinical trial. METHODS: Subjects were intravenously administered one or two doses of 60 or 120 µg kg-1 MC710 (as FVIIa) once or twice (to a maximum of 180 µg kg-1 ) over up to five bleeding episodes per subject. The haemostatic efficacy of MC710 was determined for each episode by investigator evaluation, using changes in visual analogue scale (VAS) for pain relief, and/or knee joint or muscle circumference for swelling reduction, and range of motion (ROM) for improvement of joint mobility. RESULTS: In 21 treatments for bleeding episodes, 19 were rated "excellent" or "effective" 8 h after the last treatment. VAS significantly decreased over time, and ROM significantly improved over time compared with the values before treatment. One mild adverse reaction, decreased blood potassium, and two serious adverse events, both knee joint bleeding, were observed within 1 week after first administration, with no significant effect on safety. Furthermore, diagnostic markers did not show any signs of disseminated intravascular coagulation (DIC). CONCLUSION: These results show that MC710 has sufficient haemostatic efficacy and safety, and can be used as a potential bypassing agent to control bleeding in haemophilia patients with inhibitors.


Subject(s)
Factor VIIa/therapeutic use , Factor X/therapeutic use , Hemophilia A/drug therapy , Adolescent , Adult , Humans , Male , Young Adult
8.
Opt Express ; 22(1): 483-9, 2014 Jan 13.
Article in English | MEDLINE | ID: mdl-24515008

ABSTRACT

We consider a bistable system consisting of all fiber cavity driven by an external injected continuous wave. We report on front propagation in a high finesse cavity. We study the asymptotic behavior of the front velocity. We show that the front velocity is affected by the distance from the critical point associated with bistability. We provide a scaling low governing its evolution near the up-switching point of the bistable curve. We show also that the velocity of front propagation obeys a generic power law when the front velocity approaches asymptotically its linear growing value.

9.
Opt Lett ; 38(20): 4162-5, 2013 Oct 15.
Article in English | MEDLINE | ID: mdl-24321949

ABSTRACT

We experimentally demonstrate the use of cyclic pulse coding for distributed strain and temperature measurements in hybrid Raman/Brillouin optical time-domain analysis (BOTDA) optical fiber sensors. The highly integrated proposed solution effectively addresses the strain/temperature cross-sensitivity issue affecting standard BOTDA sensors, allowing for simultaneous meter-scale strain and temperature measurements over 10 km of standard single mode fiber using a single narrowband laser source only.

10.
Opt Lett ; 38(4): 471-3, 2013 Feb 15.
Article in English | MEDLINE | ID: mdl-23455106

ABSTRACT

We propose and experimentally demonstrate the use of cyclic pulse coding to improve the performance of hybrid Raman/fiber Bragg grating (FBG) fiber-optic sensors, for simultaneous measurement of distributed static temperature and discrete dynamic strain over the same sensing fiber. Effective noise reduction is achieved in both Raman optical time-domain reflectometry and dynamic interrogation of time-division-multiplexed fiber FBG sensors, enhancing the sensing range resolution and providing real-time point dynamic strain measurement capabilities. The highly integrated sensor scheme employs broadband apodized low-reflectivity FBGs, a single narrowband optical source, and a shared receiver block.

11.
Opt Lett ; 38(15): 2877-80, 2013 Aug 01.
Article in English | MEDLINE | ID: mdl-23903168

ABSTRACT

A cyclic pulse coding technique is proposed and experimentally demonstrated for fast implementation of long-range Brillouin optical time-domain analysis (BOTDA). The proposed technique allows for accurate temperature and strain measurements with meter-scale spatial resolution over kilometers of standard single-mode fiber, with subsecond measurement times.

12.
Arch Razi Inst ; 78(2): 593-599, 2023 04.
Article in English | MEDLINE | ID: mdl-37396738

ABSTRACT

Antioxidant and antibacterial chemicals are key sources in medicinal plants. Alkaloids, phenolics, steroids, terpenes, flavonoids, terpenes, and volatile oils are a few of these plants' secondary metabolites. Phytochemicals, particularly the secondary metabolites produced by plants, are important for human nutrition, well-being, illness prevention, and antibacterial properties. This study aimed to ascertain the aqueous broccoli extract's chemical makeup. The phytochemical molecule that the GC-MS technique identified. The DPPH assay, which is appropriate for regular plant material screening, was performed to assess the antioxidant capacities of broccoli extract (in vitro). Subsequently looks at how well they perform against different Gram-positive and Gram-negative harmful microorganisms. GC-MS analysis of Broccoli extract revealed the existence of the9-Octadecenamide, [C18H35O], Hexadecane [c16h34] and 2, 2, 2-trifluoroethyl 2-methyltetrahydro-5-oxo-3- furancarboxylate [C23H33NO6]. There were significant changes in the extract's ascorbic acid-free radical scavenging activity at 200, 100, and 25 g/ml (P≤0.05), and the activity was dose-dependent. The effectiveness of aqueous broccoli extract as a powerful, broad-spectrum antibacterial agent against tested bacteria is demonstrated by an increase in the diameter of the inhibition zone, which increases in direct proportion to the concentration of the extract and even surpasses the activity of some antibiotics. An appropriate concentration of aqueous broccoli extract strongly inhibits microbial and antioxidant growth, especially when treating external infections without any danger against resistant bacterial isolates; it is strongly advised to use aqueous broccoli extract as a cost-effective alternative antibacterial and antioxidant agent.


Subject(s)
Antioxidants , Brassica , Humans , Animals , Antioxidants/pharmacology , Plant Extracts/pharmacology , Plant Extracts/chemistry , Gas Chromatography-Mass Spectrometry , Anti-Bacterial Agents/pharmacology , Phytochemicals/analysis , Phytochemicals/chemistry , Phytochemicals/pharmacology , Terpenes/analysis
13.
Environ Int ; 160: 107069, 2022 02.
Article in English | MEDLINE | ID: mdl-34974237

ABSTRACT

In recent decades, the possibility that use of mobile communicating devices, particularly wireless (mobile and cordless) phones, may increase brain tumour risk, has been a concern, particularly given the considerable increase in their use by young people. MOBI-Kids, a 14-country (Australia, Austria, Canada, France, Germany, Greece, India, Israel, Italy, Japan, Korea, the Netherlands, New Zealand, Spain) case-control study, was conducted to evaluate whether wireless phone use (and particularly resulting exposure to radiofrequency (RF) and extremely low frequency (ELF) electromagnetic fields (EMF)) increases risk of brain tumours in young people. Between 2010 and 2015, the study recruited 899 people with brain tumours aged 10 to 24 years old and 1,910 controls (operated for appendicitis) matched to the cases on date of diagnosis, study region and age. Participation rates were 72% for cases and 54% for controls. The mean ages of cases and controls were 16.5 and 16.6 years, respectively; 57% were males. The vast majority of study participants were wireless phones users, even in the youngest age group, and the study included substantial numbers of long-term (over 10 years) users: 22% overall, 51% in the 20-24-year-olds. Most tumours were of the neuroepithelial type (NBT; n = 671), mainly glioma. The odds ratios (OR) of NBT appeared to decrease with increasing time since start of use of wireless phones, cumulative number of calls and cumulative call time, particularly in the 15-19 years old age group. A decreasing trend in ORs was also observed with increasing estimated cumulative RF specific energy and ELF induced current density at the location of the tumour. Further analyses suggest that the large number of ORs below 1 in this study is unlikely to represent an unknown causal preventive effect of mobile phone exposure: they can be at least partially explained by differential recall by proxies and prodromal symptoms affecting phone use before diagnosis of the cases. We cannot rule out, however, residual confounding from sources we did not measure. Overall, our study provides no evidence of a causal association between wireless phone use and brain tumours in young people. However, the sources of bias summarised above prevent us from ruling out a small increased risk.


Subject(s)
Brain Neoplasms , Cell Phone , Glioma , Adolescent , Adult , Brain Neoplasms/epidemiology , Brain Neoplasms/etiology , Case-Control Studies , Child , Electromagnetic Fields/adverse effects , Glioma/etiology , Humans , Male , Radio Waves/adverse effects , Young Adult
14.
Opt Express ; 19(15): 14210-6, 2011 Jul 18.
Article in English | MEDLINE | ID: mdl-21934784

ABSTRACT

We demonstrate the cnoidal wave formation in a two-laser system with a saturable absorber in the cavity of one of the lasers. Another laser is used to activate the saturable absorber in order to control the pulse shape, width, intensity and frequency. Using the three-level laser model based on the Statz--De Mars equations, we show that for any value of the saturable absorber parameter there exists a certain modulation frequency for which the pulse shape is very close to a soliton shape with less than 5% error at the pulse base. Such a device may be prominent for optical communication and laser engineering applications.

15.
Opt Lett ; 36(23): 4623-5, 2011 Dec 01.
Article in English | MEDLINE | ID: mdl-22139263

ABSTRACT

Modulation instability in a passive fiber cavity is revisited. We address the problem in the statement with a continuous-time Ikeda map, rather than in the mean-field limit. It is found that plane wave solutions are unstable for both normal and anomalous dispersion regimes of an optical fiber. The origin of the instability in the continuous-time Ikeda map is in the mode mixing introduced by the beam splitter. The obtained conditions for the instability were compared with ones known for the discrete-time Ikeda map, showing appreciable difference, which, however reduces in the mean-field limit.

16.
Opt Lett ; 36(8): 1359-61, 2011 Apr 15.
Article in English | MEDLINE | ID: mdl-21499356

ABSTRACT

We demonstrate in an optical fiber that third-order dispersion yields an unexpected symmetry-breaking dynamics of the modulational instability spectrum. It is found in particular that this spectral asymmetry does not smoothly and monotonically increase when approaching the zero-dispersion wavelength. Instead, it exhibits several local extrema and it can even be reversed at a particular dispersion value. We interpret this behavior as resulting from interactions between dispersive waves and solitons generated from modulation instability.

17.
Haemophilia ; 17(5): 771-6, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21682824

ABSTRACT

Studies conducted in European and North American countries have demonstrated that various factors including races affect the frequency of inhibitor formation in haemophilia patients. The present study was undertaken to analyse factors affecting the incidence of inhibitor formation in Japanese haemophilia A and B patients. Analytical data were retrospectively collected from haemophilia A and B patients born after 1988, the year when monoclonal antibody-purified factor VIII products were first marketed in Japan. Various data were collected from 184 patients (153 cases of haemophilia A; 31 cases of haemophilia B). The sample size of haemophilia B cases was too small to reveal any significant differences between the inhibitor formation group and the inhibitor-free group in any of background variables. For patients with haemophilia A, on the other hand, univariate analysis identified the severity of haemophilia and a positive family history of inhibitor development as risk factors for the formation of inhibitors. In analyses of the clotting factor products used, the incidence of inhibitor formation did not differ significantly between the group treated with plasma-derived products (29.7%) and the group treated with recombinant products (25.0%). When background variables were compared, age was higher in the group treated with plasma-derived products but none of the other background variables differed between the two groups. These results suggest that in Japanese haemophilia patients, the type of clotting factor preparations used for therapy has not influenced the incidence of inhibitor formation.


Subject(s)
Coagulants/immunology , Factor IX/immunology , Factor VIII/immunology , Hemophilia A/immunology , Hemophilia B/immunology , Isoantibodies/immunology , Adolescent , Adult , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/therapeutic use , Child , Child, Preschool , Coagulants/therapeutic use , Factor IX/therapeutic use , Factor VIII/therapeutic use , Female , Hemophilia A/drug therapy , Hemophilia B/drug therapy , Humans , Japan , Male , Recombinant Proteins/immunology , Recombinant Proteins/therapeutic use , Retrospective Studies , Risk Factors , Young Adult
18.
Occup Environ Med ; 68(9): 686-93, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21659468

ABSTRACT

OBJECTIVES: The objective of this study was to develop an estimate of a radio frequency (RF) dose as the amount of mobile phone RF energy absorbed at the location of a brain tumour, for use in the Interphone Epidemiological Study. METHODS: We systematically evaluated and quantified all the main parameters thought to influence the amount of specific RF energy absorbed in the brain from mobile telephone use. For this, we identified the likely important determinants of RF specific energy absorption rate during protocol and questionnaire design, we collected information from study subjects, network operators and laboratories involved in specific energy absorption rate measurements and we studied potential modifiers of phone output through the use of software-modified phones. Data collected were analysed to assess the relative importance of the different factors, leading to the development of an algorithm to evaluate the total cumulative specific RF energy (in joules per kilogram), or dose, absorbed at a particular location in the brain. This algorithm was applied to Interphone Study subjects in five countries. RESULTS: The main determinants of total cumulative specific RF energy from mobile phones were communication system and frequency band, location in the brain and amount and duration of mobile phone use. Though there was substantial agreement between categorisation of subjects by cumulative specific RF energy and cumulative call time, misclassification was non-negligible, particularly at higher frequency bands. Factors such as adaptive power control (except in Code Division Multiple Access networks), discontinuous transmission and conditions of phone use were found to have a relatively minor influence on total cumulative specific RF energy. CONCLUSIONS: While amount and duration of use are important determinants of RF dose in the brain, their impact can be substantially modified by communication system, frequency band and location in the brain. It is important to take these into account in analyses of risk of brain tumours from RF exposure from mobile phones.


Subject(s)
Algorithms , Brain/radiation effects , Cell Phone , Radiation Dosage , Radio Waves , Australia , Canada , Environmental Exposure/statistics & numerical data , Epidemiologic Studies , France , Humans , Israel , New Zealand , Surveys and Questionnaires
19.
Opt Lett ; 35(8): 1194-6, 2010 Apr 15.
Article in English | MEDLINE | ID: mdl-20410964

ABSTRACT

We demonstrate that modulation instability gain of time-localized signals (i.e., pulsed signals) depends strongly on the third-order dispersion, contrary to the well-known case of time-extended signals (cw signals). This surprising contribution of an odd dispersion term on this four-photon-mixing process is established analytically and confirmed by numerical simulations.

20.
Phys Rev Lett ; 105(7): 074101, 2010 Aug 13.
Article in English | MEDLINE | ID: mdl-20868047

ABSTRACT

A method is proposed to solve the challenging problem of determining the supratransmission threshold (onset of instability of harmonic boundary driving inside a band gap) in multicomponent nonintegrable nonlinear systems. It is successfully applied to the degenerate three-wave resonant interaction in a birefringent quadratic medium where the process generates spatial gap solitons. No analytic expression is known for this model showing the broad applicability of the method to nonlinear systems.

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