Experimental study of breathers and rogue waves generated by random waves over non-uniform bathymetry

We present experimental evidence of formation and persistence of localized waves, breathers, and solitons, occurring in a random sea state and uniformly traveling over non-uniform bathymetry. Recent studies suggest connections between breather dynamics and irregular sea states and between extreme wave formation and breathers, random sea states, or non-uniform bathymetry individually. In this paper, we investigate the joint connection between these phenomena, and we found that breathers and deep-water solitons can persist in more complex environments. Three different sets of significant heights have been generated within a Joint North Sea Wave Observation Project wave spectrum, and the wave heights were recorded with gauges in a wave tank. Statistical analysis was applied to the experimental data, including the space and time distribution of kurtosis, skewness, Benjamin–Feir index, moving Fourier spectra, and probability distribution of wave heights. Stable wave packages formed out of the random wave field and traveling over shoals, valleys, and slopes were compared with exact solutions of the nonlinear Schrödinger equation with a good match, demonstrating that these localized waves have the same structure as deep-water breathers. We identify the formation of rogue waves at moments and over regions where the kurtosis and skewness have local maxima. These results provide insights for understanding of the robustness of Peregrine and higher-order Akhmediev breathers, Kuznetsov–Ma solitons, and rogue waves, and their occurrence in realistic oceanic conditions, and may motivate analogous studies in other fields of physics to identify limitations of exact weakly nonlinear models in non-homogeneous media

Mucormycose Otocerebrale: À Propos D\'un Cas

La mucormycose est une affection mycosique rare mais souvent fatale, survenant sur des terrains débilités. Elle est due à la prolifération de champignons cosmopolites de la famille de mucorales. Elle entraîne des lésions délabrantes et extensives des parties molles avec risque de thromboses vasculaires. Observation : nous rapportons l\'observation d\'une petite fille, âgée de 3 ans , issue d\'un mariage consanguin, hypotrophe, hospitalisée pour otite externe évoluant depuis 3 semaines. La patiente a bénéficié d\'une antromastoidectomie et a été mise sous antibiotiques. Devant une aggravation de l\'état local, avec extension de la nécrose et destruction du conduit auditif externe, une infection mycosique est fortement suspectée, sur un terrain particulier de déficit immunitaire probable. L\'examen parasitologique d\'un prélèvement local a mis en évidence la présence de filaments mycéliens dont la culture a isolé un Rhizopus oryzae, confirmé aussi par l\'étude anatomopathologique. L\'exploration de l\'immunité a mis en évidence un déficit de l\'immunitaire céllulaire.Un traitement par amphotéricine B était mal toléré (choc anaphylactique), l\'évolution spontanée était rapidement défavorable avec une extension locorégionale importante et une thrombophlébite du sinus latéral homolatéral, aboutissement au décés. Conclusion : la localisation oto cérebrale de la mucormycose est exeptionnelle, on doit y penser devant une otite externe maligne sur un terrain particulier. La prise en charge doit être urgente afin d\'augmenter les chances de survie.Mucormycosis is a relatively rare, potentially life-threatening, fungal infection. It occurs predominately in immunocompromised hosts. Vascular invasion, thrombosis and rapid ischemic necrosis of infected tissue are the most characteristic features of this pathology. Early diagnosis and consequently effective treatment are needed to save life in this fatal condition. Report: We report a case of otocerebral mucormycosis occurring in an hypotrophic 3-years old girl suffering from language retardation and chronic diarrhea. Immune system\'s exploration revealed a profound cell-mediated immunity defect. The diagnosis was suspected because of the rapidly extensive necrosis of the external ear conduct, the existence of lateral sinus thrombosis and the resistance to an aggressive antibiotic therapy.The diagnosis was confirmed by identifying Rhizopus oryzae by pathological examination of the necrotic tissue. Treatment by intravenous amphotericin B was certainly lately begun and unfortunately complicated by anaphylactic shock. Because no alternative drug was possible, such as liposomal amphotericin B, the girl rapidly died. Conclusion: Otocerebral mucormycosis is extremely rare.It must be considered when ear lesions are necrotic and rapidly extensive mainly in patients with predisposing conditions. Successful treatment requires tissue excision and early injection of amphotericin B, preferably in its liposomal presentation. Journal Tunisien d\'ORL et de chirurgie cervico-faciale Vol. 16 2006: pp. 42-4

Les Ethmoidites Aigues Exteriorisees De L\'enfant Etude De 11 Observations

Les ethmoïdites sont les sinusites les plus fréquentes chez l\'enfant de moins de 3 ans. La gravité de cette affection est liée à l\'extériorisation orbito-oculaire et endocrânienne de l\'infection. But : Analyser les caractéristiques clinico- radiologiques et thérapeutiques de cette affection. Patients et méthodes : Il s\'agit d\'une étude rétrospective portant sur 11 enfants hospitalisés pour ethmoïdite aigue, dans le service de pédiatrie du CHU Farhat Hached de Sousse, durant une période de 6 ans. Résultats : L\'âge moyen de nos patients était de 4 ans et 1/2, ils se répartissaient en 8 filles et 3 garçons. Le délai de consultation était de trois jours en moyenne. La fièvre et l\'oedème palpébral étaient deux critères constants chez tous nos patients. L\'atteinte était unilatérale dans neuf cas, et bilatérale dans deux cas. La TDM éthmoïdo-orbitaire et cérébrale, réalisée pour tous les patients, nous a permis de confirmer le diagnostic et de préciser l\'extension locorégionale. Une cellulite préseptale, une cellulite orbitaire, un abcès sous périosté étaient retrouvées, dans trois cas et une collection orbitaire dans les deux autres. Une bithérapie (céfotaxime-fosfomycine) était prescrite de première intention chez 10 patients. La metronidazole a été associée dans 3 cas Un drainage chirurgical était réalisé chez quatre patients. L\'évolution était favorable dans tous les cas. Conclusion : contenu de la gravité et les germes rencontrés dans cette affection, l\'antibiothérapie de première intention doit être large, précoce et intensive. Le recours au drainage est impératif en cas de collection orbitaire.Acute ethmoiditis are bacterial infections of ethmoid sinuses, which may spread to the orbital or the endocranial spaces.They are the most frequent among bacterial sinusitis before 3 years. Population and methods:Our study is retrospective, it included all children hospitalized in our pediatric unit from 2000 to 2006 for an acute ethmoiditis. We analyzed clinical and radiological presentations, and discussed therapeutic modalities used to treat this pathology. Results:Over this 6-years period, 11 children (mean age 4.5 years) where hospitalized for acute ethmoïdites.They were 3 boy and 8 girls. All patients presented with high fever and palpabral oedems. Etmoïditis was unilateral in 9 Children and bilateral in two. Ethmoïdio-orbital CT scan confirmed acute ethmoïdis, the cerebral one assessed intra-cranial diffusion. The acute ethmoidis was complicated with, preseptal cellulites in three cases, orbital cellulitis in three cases, subperiostal abscess in three others and orbital collection in two patients. Most children received an association of cefotaxisme and fosfomycemie for a mean duration of 13 days. Metronidazole was associated to the previous antibiotherapy in three cases. Four patients, required surgical treatment in addition to antibiotherapy.All children saw favorable out come. Conclusion:It is always difficult to found the bacteria responsible for an acute ethmoiditis. The first antibiotic therapy must be chosen to be effective in the most frequently responsible bacteria tacking in consideration the potentiel severity of this sinusitis. Journal Tunisien d\'ORL et de chirurgie cervico-faciale Vol. 16 2006: pp. 22-2

Exploring the Potential of Sulfonamide-Dihydropyridine Hybrids as Multitargeted Ligands for Alzheimer’s Disease Treatment

Alzheimer’s disease (AD) is a multifactorial neurodegenerative disease that has a heavy social and economic impact on all societies and for which there is still no cure. Multitarget-directed ligands (MTDLs) seem to be a promising therapeutic strategy for finding an effective treatment for this disease. For this purpose, new MTDLs were designed and synthesized in three steps by simple and cost-efficient procedures targeting calcium channel blockade, cholinesterase inhibition, and antioxidant activity. The biological and physicochemical results collected in this study allowed us the identification two sulfonamide-dihydropyridine hybrids showing simultaneous cholinesterase inhibition, calcium channel blockade, antioxidant capacity and Nrf2-ARE activating effect, that deserve to be further investigated for AD therapy.This work was supported by the Regional Council of Franche-Comté (2022Y-13659 and 13660 Accurate Project).Peer reviewe

Localized instabilities of the Wigner equation as a model for the emergence of Rogue Waves

In this paper, we model Rogue Waves as localized instabilities emerging from homogeneous and stationary background wavefields, under NLS dynamics. This is achieved in two steps: given any background Fourier spectrum P(k), we use the Wigner transform and Penrose’s method to recover spatially periodic unstable modes, which we call unstable Penrose modes. These can be seen as generalized Benjamin–Feir modes, and their parameters are obtained by resolving the Penrose condition, a system of nonlinear equations involving P(k). Moreover, we show how the superposition of unstable Penrose modes can result in the appearance of localized unstable modes. By interpreting the appearance of an unstable mode localized in an area not larger than a reference wavelength λ0 as the emergence of a Rogue Wave, a criterion for the emergence of Rogue Waves is formulated. Our methodology is applied to δ spectra, where the standard Benjamin–Feir instability is recovered, and to more general spectra. In that context, we present a scheme for the numerical resolution of the Penrose condition and estimate the sharpest possible localization of unstable modes. Keywords: Rogue Waves; Wigner equation; Nonlinear Schrodinger equation; Penrose modes; Penrose conditio

Supporting information : Exploring the Potential of Sulfonamide-Dihydropyridine Hybrids as Multitargeted Ligands for Alzheimer’s Disease Treatment

Peer reviewe

Nasopharyngeal Carcinoma Metastatic to the Mandible

Nasopharyngeal carcinoma (NPC) is one of the most common malignancies in the head and neck region, especially among those of Chinese origin. NPC has multifactorial aetiologies including genetic susceptibility, consumption of food with high salt content, and the Epstein–Barr virus. The primary tumour usually arises from the lateral walls of the nasopharynx and is characterized by a rich sub-mucosal lymphatic structure, often leading to cervical lymph node metastasis. Distant metastasis has been recognized to be a major cause of treatment failure in patients with nasopharyngeal carcinoma. Bone, liver and lung are the most frequent sites of NPC metastases

Matter rogue wave in Bose-Einstein condensates with attractive atomic interaction

We investigate the matter rogue wave in Bose-Einstein Condensates with attractive interatomic interaction analytically and numerically. Our results show that the formation of rogue wave is mainly due to the accumulation of energy and atoms toward to its central part; Rogue wave is unstable and the decay rate of the atomic number can be effectively controlled by modulating the trapping frequency of external potential. The numerical simulation demonstrate that even a small periodic perturbation with small modulation frequency can induce the generation of a near-ideal matter rogue wave. We also give an experimental protocol to observe this phenomenon in Bose-Einstein Condensates

Identification and Characterization of Microsporidia from Fecal Samples of HIV-Positive Patients from Lagos, Nigeria

BACKGROUND: Microsporidia are obligate intracellular parasites that infect a broad range of vertebrates and invertebrates. They have been increasingly recognized as human pathogens in AIDS patients, mainly associated with a life-threatening chronic diarrhea and systemic disease. However, to date the global epidemiology of human microsporidiosis is poorly understood, and recent data suggest that the incidence of these pathogens is much higher than previously reported and may represent a neglected etiological agent of more common diseases indeed in immunocompetent individuals. To contribute to the knowledge of microsporidia molecular epidemiology in HIV-positive patients in Nigeria, the authors tested stool samples proceeding from patients with and without diarrhea. METHODOLOGY/PRINCIPAL FINDINGS: Stool samples from 193 HIV-positive patients with and without diarrhea (67 and 126 respectively) from Lagos (Nigeria) were investigated for the presence of microsporidia and Cryptosporidium using Weber's Chromotrope-based stain, Kinyoun stain, IFAT and PCR. The Weber stain showed 45 fecal samples (23.3%) with characteristic microsporidia spores, and a significant association of microsporidia with diarrhea was observed (O.R. = 18.2; CI: 95%). A similar result was obtained using Kinyoun stain, showing 44 (31,8%) positive samples with structures morphologically compatible with Cryptosporidium sp, 14 (31.8%) of them with infection mixed with microsporidia. The characterization of microsporidia species by IFAT and PCR allowed identification of Enterocytozoon bieneusi, Encephalitozoon intestinalis and E. cuniculi in 5, 2 and 1 samples respectively. The partial sequencing of the ITS region of the rRNA genes showed that the three isolates of E.bieneusi studied are included in Group I, one of which bears the genotype B. CONCLUSIONS/SIGNIFICANCE: To our knowledge, this is the first report of microsporidia characterization in fecal samples from HIV-positive patients from Lagos, Nigeria. These results focus attention on the need to include microsporidial diagnosis in the management of HIV/AIDS infection in Nigeria, at the very least when other more common pathogens have not been detected