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We investigate the formation of the Kuznetsov-Ma solitons and Ahkmediev breathers in a cold Λ-type three-level atomic system that interacts with a probe field of nanosecond pulse duration and a strong continuous-wave driving field via an electromagnetically induced transparency process. Within the framework of the Hirota equation, exact explicit analytical solutions of these breathers are obtained, showing different amplitude and oscillatory characteristics. Numerical simulations confirm the stability of both types of breathers against non-integrable perturbations that are caused by the nonvanishing decay rates of atomic states. We show that both breathers thus generated can propagate at a quite low group velocity.

We use a nonrecursive Darboux transformation method to obtain a special hierarchy of rogue wave solutions of the vector Lakshmanan–Porsezian–Daniel equation, which can govern the propagation of ultrashort optical pulses in a long-haul telecommunication fiber. In terms of the exact rational solutions, we demonstrate several interesting rogue wave dynamics such as rogue wave doublets, quartets and sextets. The modulation instability responsible for the excitation of rogue waves from an unstable continuous background in such a complex nonlinear system is also discussed.

6 pags., 5 figs., 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., This work was supported by the National Natural Science Foundation of China (Grant No. 11474051) and by the European Union under the European Unions Horizon 2020 research and innovation program MSCA-RISE-2015 (Grant No. 691051). Ph. G. was supported by the Indo-French Centre for the Promotion of Advanced Research (IFCPAR/ CEFIPRA) under Contract No. 5104-2. The work of J. M. S.-C. was supported by MINECO under Contract No. TEC2015-71127-C2-1-R and by the Comunidad Autonoma de Madrid (CAM) under Contract No. S2013/ MIT-2790

We present universal fundamental rogue wave solutions in the context of self-induced transparency for the coupled optical and matter waves, and confirm numerically that they can be excited amid the onset of modulation instability.

The resonant interaction of an optical field with two-level doping ions in a cryogenic optical fiber is investigated within the framework of nonlinear Schrodinger 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.

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.

Exploratory data analysis and geovisualization have opened new paths for displaying and analyzing data. Alternate views of the same data set provide more insight into the nature of the data. The choropleth map has been the primary display device for portraying the spatial distribution of statistical data aggregated over areal units. However, the standard choropleth map is not as informative with respect to the statistical distribution of the data. Data classification for classed choropleth maps, as well as the transformation of numeric values into lightness values, filters out much of the information regarding the underlying statistical distribution of the data. Traditionally, the map legend has the role of connecting lightness values to their numeric counterparts and providing some information regarding the statistical properties of the data. It is proposed here that a more versatile legend can be constructed based on the ogive cumulative frequency diagram. Ogive legends can present the overall statistic...

In this article, an on-line system allowing users to perform detailed queries of a database of individual records containing confidential information is described. The results of the query can be reported in table, comma-delimited file, or map format for spatial aggregates defined by the user. This system addresses some important social problems arising from the development of large digital databases of information on individuals that can be analysed using GIS, including violating privacy and confidentiality protections, profiling, and distributing multiple, unregulated copies of source databases. It also recognizes the needs of public agencies to distribute information and of individuals to have access to public information. The system is designed as an open-architecture server-side system. A database of six years' worth of injury mortality records compiled from data provided by the Connecticut Department of Public Health is developed to demonstrate the process of formulating user queries and the corresponding results. The prototype system described uses technology to address the needs of public agencies to provide access to public information in a way that ensures database integrity, protects privacy and confidentiality, and enhances access to public information.

Drainage density, defined as river length per unit area, is an important tool to reveal the concealed active tectonics in the Quaternary-covered North China plain (NCP). The distribution of high-drainage density is characteristic of zonation and regionalisation. There are two sets of belts with high-drainage densities, which trend at 45–50 and 315–320°. The different locations and trends of these belts make it possible to divide the NCP into three regions. They are Beijing–Tianjin–Tangshan region in the north, Jizhong–Lubei region in the middle and Xingtai region in the south. Similarly located regions can be defined using contours of deformation data from geodetic-surveys from 1968 to 1982. Belts of high-drainage density are spatially coincident with seismotectonic zones and overlie concealed active faults. These active structures strike at an angle of ≈15° to that in the Eocene–Oligocene, a discordance, which may be an indication of an evolution of the fault pattern through time in the NCP during the Cenozoic. The current phase has more important consequences regarding seismic hazards in the NCP.

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.

To search for the prevalence and a screening model for hearing impairment in the neonatal intensive care unit (NICU) infants.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.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%.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.

The diode-end-pumped continuous-wave Nd:LuAG ceramic lasers at 1064 nm and 1123 nm with 4F3∕2→4I11∕2 transition are here presented for the first time. For the 1064 nm laser operation, the output has been optimized using output couplers with different transmissions. A maximum output power of 8.3 W was achieved under an incident pump power of 20.4 W with a conversion efficiency of 40.7%. Replacing the output coupler based on reasonable coating design for 1123 nm oscillation, a continuous-wave laser with single-wavelength at 1123 nm was obtained with the same ceramic. At an incident pumped power of 20.4 W, an output power of 3.5 W was achieved with a conversion efficiency of 17.2%.

We report on the third Stokes light from a potassium titanyle arsenate (KTA) crystal with a Raman shift of 234 cm−1. A 25 mm long x-cut KTA crystal was intracavity pumped by an acousto-optic Q-switched Nd:Lu0.5Y0.5VO4 polarized laser at 1065 nm. The fundamental, first, second, and third Stokes lights oscillated and shared the same resonator, but only the third Stokes light at 1151 nm was output based on appropriate coated cavity mirrors. At an incident pump power of 8.2 W and a pulse repetition frequency of 15 kHz, an average output power of 430 mW and a pulse width of 4.7 ns were obtained, with the diode to Raman output conversion efficiency of 5.2%.

Direct reaction is particularly useful in studying the nuclear structure of neutron-rich nuclei. By the use of the recoiled proton tagging technique, knockout reaction was developed into a clean spectroscopic probe and was applied to the study of the exotic structures of 6He and 8He. The most accurate parameters and related spectroscopic factor was obtained for the ground state of 7He. The Multi-neutron detection technique was also implemented, with which the resonant states of 8He and the corresponding neutron-neutron correlation function were measured. The cluster structure of 12Be was studied via inelastic excitation followed by coincidently recording the decay products, and molecular-like resonant states were observed for α -8He and 6He-6He decaying channels. These states are part of the molecular rotational bands and therefore clearly support the highly clustering structure of 12Be.