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This experiment was conducted to investigate the effects of

This study aimed to establish a predictive model and nomogram based on routine laboratory blood indicators and clinical symptoms, subsequently providing a rapid risk assessment of norovirus (NoV) infection in children. This retrospective study enrolled 307 pediatric patients with symptoms of acute gastroenteritis and detected NoV using real-time quantitative polymerase chain reaction. Significant indicators selected by multivariate logistic regression, including routine blood tests and consultation symptoms, were used to develop the nomogram. We divided the sample into training and internal validation sets and performed external validation of the final model. Furthermore, we evaluated the clinical performance using the Akaike information criterion (AIC), area under the curve (AUC), calibration curve, decision curve analysis (DCA), sensitivity, specificity, concordance rate, positive predictive value, and negative predictive value. Overall, 153 cases were NoV-PCR-positive, and 154 were negative. The multivariate logistic regression included five predictors of NoV infection, including symptoms of vomiting, upper respiratory tract infection, and indicators of white blood cells, lymphocyte absolute counts, and platelet counts. The nomogram showed a significant predictive value with overall internal set diagnosis, with an AUC of 0.827 (95% confidence interval (CI): 0.785–0.868), and 0.812 (95% CI: 0.755–0.869) with 0.799 (95% CI: 0.705–0.894) in the training and internal validation sets, respectively. Nevertheless, the AUC in the external validation set was higher (0.915; 95% CI: 0.862–0.968). This nomogram is a useful tool for risk assessment for NoV infection. Moreover, the evaluated indicators are accessible, substantially reducing the time for laboratory testing.

By simultaneously using a multi-walled carbon nanotube (MWCNT) and a monolayer graphene saturable absorber (SA) in the cavity, a laser-diode-pumped dual-loss-modulated passively Q-switched Tm:LuAG laser at 2 mu m is demonstrated for the first time. In comparison with the singly passively Q-switched laser with MWCNT or monolayer graphene SA, the doubly passively Q-switched laser with both MWCNT and monolayer graphene SA can generate shorter pulse width and higher peak power. A maximum pulse width compression ratio of 2.8 and a highest peak power enhancement factor of 4 were obtained at the incident pump power of 5.8 W, respectively. The experimental results show that the dual-loss modulation is an efficient method to compress the pulse widths and improve the peak powers of the Q-switched lasers at 2 mu m.

By using monolayer graphene as saturable absorber, a passively Q-switched Tm:LuAG laser with high efficiency at 2 μm is demonstrated. At the incident pump power of 5.8 W, pulses with duration of 235 ns and maximum average output power of 873 mW were obtained at a repetition rate of 72 kHz. This is, to the best of our knowledge, the highest average output power, as well as the narrowest pulse width, ever obtained among graphene-based passively Q-switched solid-state bulk lasers at 2 μm regime.

An actively Q-switched Tm:SSO laser was realized by using an acoustic-optical (AO) modulator, and stable Q-switching operation was obtained with the pulse repetition frequency (PRF) varying from 1 kHz to 10 kHz. At PRF of 1 kHz, the Tm:SSO laser yielded a shortest 308 ns pulse with M2 factor less than 1.6 at 1968 nm, corresponding to a single pulse energy of 128 μJ and pulse peak power of 416 W. The experimental results indicate the Tm:SSO crystal is favorable for obtaining low PRF 2 μm laser pulses.

Patients with hematological malignancies (HMs) are at a higher risk for bloodstream infections (BSIs), which pose significant burden on morbidity and mortality. Better risk stratification helps in medical decision making, increasing efficiency and reducing economic burden. The aim of this study was to develop and validate a reliable prediction model which can be used to identify HM patients at higher risk for BSIs.We conducted a retrospective cohort study in three university-affiliated hospitals in Hunan Province, China, from January 2010 to April 2015. A total of 521 HMs patients with BSIs were finally included in this study and were divided into the derivation set and validation set. Survivors and non-survivors were compared to identify the predictors of 30-day mortality.The multivariate analysis yielded the following significant mortality-related risk factors: age 60 years (95% CI 1.047-5.474), relapsed or uncontrolled malignancy (95% CI 2.043-14.029), Pitt bacteremia score 3 (95% CI 1.614-6.35), prolonged neutropenia (95% CI 1.181-5.824), use of vasopressors (95% CI 3.009-12.210), acute respiratory failure (95% CI 3.061-14.911), fungemia (95% CI 1.334-12.121), inadequate antibiotic treatment (95% CI 1.682-7.591), albumin 30 g/L (95% CI 1.030-3.446), TBil 34.2 µmol/L (95% CI 1.109-5.438). In both derivation and validation sets, our model showed reliable prediction value with areas under the receiver operating curve of 0.876 and 0.873.The risk factors in this study have the ability to identify patients with HMs and BSIs at high risk for mortality. Our model provides an excellent foundation for predicting 30-day morality in HM patients suffering from BSI and helps target high-risk patients for management decision making.

In this paper, we present a diode-pumped continuous-wave tunable and Q-switched Tm:SSO laser with a semiconductor saturable absorber mirror. In continuous-wave regime, a maximum output power of 340 mW at 1,980.7 nm was obtained. With a quartz plate, wavelength-tunable continuous-wave operation was achieved from 1,922 to 2,020 nm. In Q-switched regime, a maximum output pulse energy of 14.7 μJ under a repetition rate of 800 Hz and a minimum pulse width of 7.6 μs corresponding to a repetition rate of 8.8 kHz around 1,974.4 nm were obtained from the passively Q-switched Tm:SSO laser.

Sub-aperture coherence (SAC) is a classical phase control method for high-precision beam steering using liquid crystal optical phased arrays (LCOPA). On this basis, radial sub-aperture coherence (RSAC) and symmetrical radial sub-aperture coherence (SRSAC) were proposed, which guarantee the stability of steering angles when the beam aperture and incident position fluctuate. In this article, the pre-existing one-dimensional SRSAC was firstly extended to a more universal 2D phase generation algorithm. Meanwhile, for the intractable problem of local precision defects caused by the basic two-dimensional variable period grating (2D-VPG) algorithm, we tracked their locations accurately and designed a targeted elimination method carefully. So these remarkable error peaks could be thoroughly removed by using 2D-SRSAC optimized by the local precision defect elimination method. Since then, all the excellent performance of 1D-SRSAC can be perfectly transplanted to 2D, which makes the non-mechanical beam steering technology using LCOPA more mature and competitive in the applications required ultra-high precision.

With the development of the GaN-based light-emitting diodes (LEDs), the need for p-GaN contacts with low resistivity, good thermal stability, and high reflectivity has become more urgent. In this paper, a novel method of surface treatment on p-GaN to form good ohmic contacts between p-GaN and Ag was proposed. We proposed a novel structure with Ag/ultrathin-ITO/p-GaN contact which shows a low contact resistivity as well as a high reflectance attributed to some isolated islands of ITO and the absence of Ni layer. The calculated ρ c of the new structure which is lower than 7×10−2W/cm2 based on the CTLM method showed that the Ag/ultrathin-ITO/p-GaN contact has a lower contact resistivity compared to the contact without the ultrathin ITO layer of which the ρ c is higher than 2 W/cm2 The Ag film cannot be ripped off by the tape which shows a good adhesion. The LEDs fabricated with this contacts showed a 30% higher luminance at 20mA forward currents as compared to the conventional LEDs.

Diode pumped continuous wave operation and passively Q-switched performances of a Nd:Sc2SiO5 laser crystal at 1.08 microns have been demonstrated. A maximum continuous wave average output power up to 1.86 W has been obtained, corresponding to an optical conversion efficiency of 20.7% and a slope efficiency of 30.4% with respect to the absorbed pump power. With a Cr4+:YAG wafer used as the saturable absorber, a passively Q-switched Nd:Sc2SiO5 laser generated a pulse as short as 22.5 ns at a repetition rate of 20 kHz. The maximum pulse energy of 44.8 μJ was achieved, corresponding to a maximum pulse peak power of 1.66 kW.

In this paper, we investigated the impact of impedance matching network on transmission efficiency in LED novel driving system based on wireless power transfer (WPT) technology, which has the capability of transfer electrical power from a power source to an electrical load without any interconnecting wires. In order to improve the power transfer ability of the WPT system, the impedance matching technology was introduced in this work, and a magnetic coupling resonance system was applied to the wireless driving LED lighting system. Due to the flexibility of matching network, the π-type L-type matching networks were chosen for source and load side, respectively. With the help of Smith Software the value of the matching network can be calculated directly. To confirm the effect of the impedance matching circuit on the LED novel driving system, an actual circuit was verified. The experiment results show that the efficiency of WPT technology drive LED lighting system can be improved from 40% to 85%. We believe that the WPT technology drive LED lighting system will make these LED lighting products more available, portable. This new technology will also gain more and more attention in the global LED lighting market.

In this work, we first proposed an innovation on GaN p-type reflective electrode in flip-chip LEDs (FCLEDs) using a novel method so called electroless silver plating (ESP). In our ESP method, we use chemical way to form a perfect Ag reflector, differ from traditional fabrication of p-type reflective electrode using electron beam deposition (EB). Under our investigation, the Ag reflective electrode formed by ESP possesses better optical and electric characteristics. Compared with EB, the reflectance of electrode by ESP over the whole visible light spectrum was 93%, higher than EB samples, which only show 82%. Otherwise, ohmic contact characteristic between metal and GaN also shows the same rule as reflectance. ESP samples exhibit better specific contact resistance than EB samples, they're 6.5 ∗ 10−3Ω · cm2 and 6 ∗ 10−2Ω· cm2, respectively. Moreover, the fantastic results of I-V as well as L-I measurement likewise verify electroless silver plating to be a potential manufacturing technology of p-type reflective electrode.

A watt-level output passively mode-locked Tm:LuAG bulk laser with an InGaAs semiconductor saturable absorber mirror (SESAM) is demonstrated for the first time. A maximum average output power of 1.21 W at 2022.9 nm has been achieved with a pulse duration of 38 ps and a repetition rate of 129.2 MHz. The results indicate the potential of Tm:LuAG crystals as candidate for realizing high power ultrafast lasers at 2 μm.

GaN-based vertical light-emitting-diodes (V-LEDs) with an improved current injection pattern were fabricated and a novel current injection pattern of LEDs which consists of electrode-insulator-semiconductor (EIS) structure was proposed. The EIS structure was achieved by an insulator layer (20-nm Ta2O5) deposited between the p-GaN and the ITO layer. This kind of EIS structure works through a defect-assisted tunneling mechanism to realize current injection and obtains a uniform current distribution on the chip surface, thus greatly improving the current spreading ability of LEDs. The appearance of this novel current injection pattern of V-LEDs will subvert the impression of the conventional LEDs structure, including simplifying the chip manufacture technology and reducing the chip cost. Under a current density of 2, 5, 10, and 25 A/cm2, the luminous uniformity was better than conventional structure LEDs. The standard deviation of power density distribution in light distribution was 0.028, which was much smaller than that of conventional structure LEDs and illustrated a huge advantage on the current spreading ability of EIS-LEDs.

In this paper, the effective coupling coefficient κeff and the self-coupling coefficient ζ1 are introduced to describe the characteristic of gratings in a resonant situation when the effects of radiation and other partial waves coupling are considered. The dependence of these two coupling coefficients on grating tooth shapes and depths and the dimensions of graded refractive index (GRIN) waveguides is numerically analysed. The results show that the gratings with linear GRIN waveguides have the largest |κeff|. The possibility of realizing a complex-coupled DFB laser, even a pure gain or loss coupled DFB laser, employing only a real refractive index coupled grating is also discussed.

We have investigated the lasing characteristics of Tm:LSO crystal in three operation regimes: continuous wave (CW), wavelength tunable and passive Q-switching based on graphene. In CW regime, a maximum output power of 0.65 W at 2054.9 nm with a slope efficiency of 21% was achieved. With a quartz plate, a broad wavelength tunable range of 145 nm was obtained, corresponding to a FWHM of 100 nm. By using a graphene saturable absorber mirror, the passively Q-switched Tm:LSO laser produced pulses with duration of 7.8 μs at 2030.8 nm under a repetition rate of 7.6 kHz, corresponding to pulse energy of 14.0 μJ.