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Within the coupled Fokas-Lenells equations framework, we show explicitly that, in contrast to the expected threefold-amplitude magnification, Peregrine solitons can reach a peak amplitude as high as 5 times the background level. Besides, the interaction of two such anomalous Peregrine solitons can generate a spikelike rogue wave of extremely high peak amplitude, depending on the parameters used. We numerically confirm that the Peregrine soliton beyond the threefold limit can be reproduced from either a deterministic initial profile or a chaotic background field, hence anticipating the feasibility of its experimental observation.
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PURPOSE: To explore the clinical significance of sonographic (US) diagnosis of fetal arachnoid cysts and to evaluate their prognosis. METHODS: Sixty fetuses deemed to have arachnoid cysts by prenatal US were included in this study. Data from serial US, prenatal and/or postnatal MRI, or post-mortem examinations were retrospectively analyzed. For live births, the developmental quotient scores were determined using the Gesell Developmental Scale. RESULTS: Thirty fetuses were diagnosed during the second trimester and another 30 fetuses were diagnosed in the third trimester. Fifty-one lesions were located in the supratentorial compartment, and 9 were located in the posterior fossa. Twenty-four lesions were isolated, and the remaining lesions were associated with intracranial and/or extra central nervous system malformations. The evolution of the cysts included progression, stability, or spontaneous resolution. The outcomes included induced abortion, intrauterine death, live birth with either normal neurodevelopment or mental retardation, and infant mortality. Two cases were lost to follow-up. The accuracy of prenatal US diagnosis was 86.2% (50/58). CONCLUSION: Prenatal US is the modality of choice for the diagnosis of fetal arachnoid cysts. Serial US examinations are critical to monitor the lesions. Moreover, prenatal MRI is a valuable complementary tool. For live births, the prognosis appears to be good.
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Cistos Aracnóideos/diagnóstico por imagem , Cistos Aracnóideos/embriologia , Adulto , Feminino , Humanos , Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Estudos Retrospectivos , Ultrassonografia Pré-Natal/métodos , Adulto JovemRESUMO
The resonant interaction of an optical field with two-level doping ions in a cryogenic optical fiber is investigated within the framework of nonlinear Schrödinger and Maxwell-Bloch equations. We present explicit fundamental rational rogue wave solutions in the context of self-induced transparency for the coupled optical and matter waves. It is exhibited that the optical wave component always features a typical Peregrine-like structure, while the matter waves involve more complicated yet spatiotemporally balanced amplitude distribution. The existence and stability of these rogue waves is then confirmed by numerical simulations, and they are shown to be excited amid the onset of modulation instability. These solutions can also be extended, using the same analytical framework, to include higher-order dispersive and nonlinear effects, highlighting their universality.
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OBJECTIVE: Inherited non-syndromic hearing loss (NSHL) is a common sensory disorder that afflicts otherwise healthy individuals. The aim of the study was to evaluate the performance of circulating single molecule amplification and re-sequencing technology (cSMART) for non-invasive prenatal testing (NIPT) of NSHL. METHOD: Neonatal inheritance of NSHL mutations was determined from bloodspots using SNaPshot genotyping. NIPT of cell-free DNA for fetal NSHL mutations in the GJB2, GJB3 and SLC26A4 genes was performed by a multiplex cSMART assay. The percentage of mutant alleles was used to deduce fetal DNA fractions and assign fetal genotypes. RESULTS: A total of 25 plasma samples selected with different fetal NSHL genotypes were coded and retrospectively analyzed by NIPT. Three normal fetuses, 18 carrier fetuses comprising seven GJB2 109G>A, four GBJ2 235delC, three GJB2 299-300delAT and four SLC26A4 IVS7-2A>G heterozygotes and four affected fetuses comprising two GJB2 109G>A homozygotes, one GBJ2 235delC homozygote and one compound GJB2 235delC/299-300delAT heterozygote were identified. All 25 fetal genotypes determined by the cSMART assay were concordant with neonatal genotypes. CONCLUSION: The cSMART assay applied to cell-free DNA isolated from maternal plasma of pregnant women is highly accurate for calling correct fetal NSHL genotypes. © 2016 John Wiley & Sons, Ltd.
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Genótipo , Técnicas de Genotipagem/métodos , Perda Auditiva/congênito , Perda Auditiva/genética , Diagnóstico Pré-Natal/métodos , Conexina 26/genética , Conexinas/genética , DNA/sangue , Feminino , Testes Genéticos/métodos , Heterozigoto , Homozigoto , Humanos , Recém-Nascido , Proteínas de Membrana Transportadoras/genética , Mutação , Fenótipo , Gravidez , Transportadores de SulfatoRESUMO
This Letter describes an intracavity pumped optical parametric oscillator (OPO) based on noncritical phase matching RbTiOPO4 (RTP) crystal driven by a laser diode end-pumping acousto-optic Q-switched Nd:YVO4 laser. Simultaneous efficient signal light at 1.6 µm and idler light at 3.1 µm outputs were obtained. At an incident pump power of 10.5 W and a Q-switching pulse repetition frequency of 60 kHz, 1.42 W at center wavelength of about 1619 nm and 0.38 W at 3108 nm were achieved, with the diode to OPO total output conversion efficiency up to 17.1%. The pulse width is about 6.5 ns for the signal light corresponding to the fundamental light at 1064 nm of about 10 ns. The spectral widths of the signal and idler light are narrower than 0.5 and 1.0 nm. The result shows that the RTP crystal is an efficient crystal to generate eye-safe and mid-infrared lights by making full use of noncritical phase matching.
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An experiment of 12C(16O,16O â 4α)12C was performed at a beam energy of 96 MeV. A large number of 4-α events were recorded in coincidence and with full particle identification (PID). This was made possible by employing a series of silicon-strip-based telescopes that provided excellent position and energy resolutions. Four narrow resonances just above the 15.1 MeV state were firmly identified in the α + 12C(7.65 MeV; Hoyle state) decay channel. Combined with the theoretical predictions, these resonant states provide new evidence for the predicted possible Hoyle-like structure in 16O above the 4-α separation threshold. Some very high-lying 4-α resonant states have also been observed and need to be further investigated.
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Registros , Telescópios , Silício , VibraçãoRESUMO
We formulate a non-recursive Darboux transformation technique to obtain the general nth-order rational rogue wave solutions to the coupled Fokas-Lenells system, which is an integrable extension of the noted Manakov system, by considering both the double-root and triple-root situations of the spectral characteristic equation. Based on the explicit fundamental and second-order rogue wave solutions, we demonstrate several interesting rogue wave dynamics, among which are coexisting rogue waves and anomalous Peregrine solitons. Our solutions are generalized to include the complete background-field parameters and therefore helpful for future experimental study.
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OBJECTIVE: To search for the prevalence and a screening model for hearing impairment in the neonatal intensive care unit (NICU) infants. METHOD: Two-stage hearing screening program by automated auditory brainstem response (AABR) were used. A first test was performed as late as possible before discharge from the NICU. Those cases who failed the initial screening underwent a second test in an outpatient setting with an interval of one month. After a failure at the second screening, the infants were referred to our audiological center for further diagnostic evaluations within three months. RESULT: The subjects included were 824 infants who discharged from NICU between September 2007 and August 2008. Seventy newborns (8.5%) failed the pre-discharge AABR test. Of those, fifty-five (78.6%) received the second AABR screening after one month, and nine referred again. These nine babies were evaluated with additional diagnostic audiological tests. Three of them were eventually identified to have sensorineural hearing loss, and one was diagnosed as auditory neuropathy. The total prevalence of hearing loss was 0.48%. CONCLUSION: Two-stage screening program of AABR may be an ideal model for hearing screening in NICU infants. The prevalence of hearing loss in our group is lower than that reported in the literature.