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It is well known how to tailor the conversion efficiency grid of a single quasi-phase-matching (QPM) grating when the involved processes are uncoupled. However, it becomes much more sophisticated in the presence of coupling between multiple processes. In this case, different processes compete for the same QPM “resources” throughout the grating, and one process can outweigh the others over a certain range of interaction. Here we propose the generalized iterative domino (GID) algorithm to meet these challenges for the first time (to our best knowledge). Instead of tailoring the strength of each “global” Fourier coefficient, GID algorithm can properly adjust the spatially varying “local” Fourier coefficients in favor of the final yield. Three methods, including cascaded single-period (C1P) structure, quasi-periodic optical superlattice (QPOS), and hyperfine aperiodic optical superlattice (HAOS) optimized by GID, are numerically and experimentally investigated under the platform of third-harmonic generation (THG). It shows that the THG efficiency of HAOS + GID can exceed the record achieved by C1P structure by 33%. This method is applicable to general wavelength converters involving with multiple coupled nonlinear processes.

Objective: To understand the risk of developing a poor prognosis in adulthood after violent injury in Taiwan. Methods: This study used the data of outpatients, from emergency departments, and from hospitalization of 2 million people under National Health Insurance from 2000 to 2015. The ICD-9 diagnostic code N-code was defined as the case of this study and was 995.8 (abused adult) or E-code was E960-E969 (homicide and intentional injury by others) The first violent injury of 18–64-year-old adults (the study group) was analyzed. Patients who had not suffered violent abuse were the control group. The groups were matched in a 1:4 ratio, and the paired variables were gender, age ±1 year, Charlson Comorbidity index (CCI) before exposure, and year of medical treatment. SAS 9.4 statistical software was used, and the Cox regression method was used for data analysis. Results: During the 15-year period, a total of 8726 people suffered from violence (34,904 controls). The incidences of common poor prognoses among the victims of violence were sleep disorder, anxiety, and depression, in 33.9%, 21.6%, and 13.2% of people, respectively. The risk (Adults, Overall) of developing Post-Traumatic Stress Disorder (PTSD), bipolar disorder, and manic disorder after being violently injured (average 9 years) was 34.86, 4.4, and 4.1 times higher than those who had not suffered violence (all p values < 0.01). The risk (Adults, Males) of developing PTSD, bipolar disorder, and manic disorder after being violently injured (average 9 years) was 30.0, 3.81, and 2.85 times higher, respectively, than those who had not suffered violence (all p values < 0.01). The risk (Adults, Females) of developing PTSD, manic disorder, and bipolar disorder after being violently injured (average 9 years) was 36.8, 6.71, and 5.65 times higher, respectively, than of those who had not suffered violence (all p values < 0.01). Conclusion: The risks of poor prognosis are higher in adults who have suffered violent abuse than in those who have not. Therefore, police, social workers, and medical personnel should pay attention to the mental state of victims of violence. They should aim to support prompt treatment, to avoid PTSD, bipolar disorder, manic disorder, etc.

Three novel anthracene-based organic dyes, denoted as AN-11, AN-12 and AN-14, were synthesized for outdoor and indoor dye-sensitized solar cell studies. Laboratory-fabricated small cells, as well as rigid and flexible modules, were prepared and analyzed for their photovoltaic performance under simulated outdoor and indoor conditions. Owing to the panchromatic absorption of visible light, the AN-11 module gives rise to a very black color and superior photovoltaic performance. Significantly, the AN-11 rigid module with a large active area of 26.80 cm2 outperforms its Z907 counterpart under indoor conditions, reaching an overall efficiency of 11.94% under 1000 lux of T5 fluorescent light. In addition, the AN-11 module exhibits good stability during weather stress tests. Finally, the AN-11 dye is cost-effective and our studies show that the photovoltaic performance of the solar cells is not affected upon lowering the synthetic cost and increasing the synthetic scale.

Commercially pure titanium (c.p. Ti) is often used in biomedical implants, but its surface cannot usually combine with the living bone. A coating of hydroxyapatite (HA) on the surface of titanium implants provides excellent mechanical properties and has good biological activity and biocompatibility. For optimal osteocompatibility, the structure, size, and composition of HA crystals should be closer to those of biological apatite. Our results show that the surface of c.p. Ti was entirely covered by rod-like HA nanoparticles after alkali treatment and subsequent hydrothermal treatment at 150 &deg, C for 48 h. Nano-sized apatite aggregates began to nucleate on HA-coated c.p. Ti surfaces after immersion in simulated body fluid (SBF) for 6 h, while no obvious precipitation was found on the uncoated sample. Higher apatite-forming ability (bioactivity) could be acquired by the samples after HA coating. The HA coating featured bone-like nanostructure, high crystallinity, and carbonate substitution. It can be expected that HA coatings synthesized from eggshells on c.p. Ti through a hydrothermal reaction could be used in dental implant applications in the future.

Thermal effect in high-power CW single-pass 1064 nm SHG for 532 nm generation using MgO:PPLN crystal has been theoretically and experimentally investigated. By careful control of the focusing condition to deal with the well-known thermal issue such as thermal lensing and dephasing in MgO:PPLN crystal, we have successfully generated >7W green output at 532nm using a 25mm long crystal without observing optical damage. This achievement has enhanced the maximum CW green power generated through MgO:PPLN crystal by a factor of 3 as compared to the common optimization under low power condition, and by a factor of 2 as compared to the scheme of single-pass multi-crystal cascading SHG. To our best knowledge, this result gives the highest CW green power via SHG of MgO:PPLN crystal. Furthermore, a systematic study for SHG optimization has shown that >30% SHG conversion efficiency can be achieved from 2W to 7W under output-power dependent optimization.

We have developed the MgO: PPLN ridge waveguide modules for efficient second harmonic generation output and optical parametrical amplification at telecom wavelength. High efficient and high damage resistance of developed MgO: PPLN waveguide modules have enabled efficient optical parametric amplification with >16dB intrinsic gain for the input signal.

A series of anthracene-based organic dyes were prepared via cost-effective synthetic procedures for dye-sensitized cell application. UV–visible and fluorescent spectra, electrochemical properties, and photovoltaic performance of the dyes were studied. Under one sun (100 mW/cm2), the AN-3 small cell outperforms others in the series. Under a dim light condition, the AN-3 modules showed PCE comparable to that of the Z907 modules. After optimizing the synthetic procedure, we found that AN-3 can be manufactured at a fairly low price.

We propose an algorithm to optimize the efficiency of coupled χ2 processes in an aperiodic optical superlattice, achieving record high efficiency of frequency tripling. Feasibility is confirmed by controlled experiment with three different design methods.

A diode-pumped intracavity optical parametric oscillator is built to demonstrate single-frequency and mod-hop free tuning operation over 20 GHz range around 3 μm. Performance is verified by measuring absorption spectrum of isotopic methane.

This paper presents a variational manifold learning for speaker recognition based on the probabilistic linear discriminant analysis (PLDA) using i-vectors. A latent variable model is introduced to compensate the constraints of the linearity in PLDA scoring and the high dimensionality in using i-vectors. A deep variational learning is formulated to jointly optimize three objectives including a regularization for variational distributions, a reconstruction based on PLDA and a manifold learning for neighbor embedding. A stochastic gradient variational Bayesian algorithm is developed to optimize the variational lower bound of log likelihood where the expectation in the objectives is estimated via a sampling method. Interestingly, the latent variables in the proposed variational manifold PLDA (vm-PLDA) are capable of decoding or reconstructing the i-vectors. The experiments on visualization and speaker recognition show the merits of vm-PLDA in manifold learning and classification.

Titanium and its alloys are widely used as biomaterials for orthopedic and dental implants because of their excellent biocompatibility and mechanical properties. However, they are considered to be bioinert; when they are inserted into the human body these implants cannot bond directly to the surrounding living bone. Through hydrothermal reaction and heat treatment, this study aimed to improve the bioactivity of a low-modulus Ti–5Nb–5Mo alloy with a hydroxyapatite (HA) surface coating that used eggshells as a Ca source. The results showed that after hydrothermal reaction at 200 °C for 48 h, the entire alkali-treated alloy surface was covered with amorphous calcium phosphate nanoparticles. When later heat-treated at various temperatures (400, 500 or 600 °C) for 48 h, the surface coating of Ti–5Nb–5Mo alloy was transformed into crystalline, rod-like HA nanoparticles. Additionally, FTIR analysis confirmed the production of HA with mixed AB-type carbonate substitutions. The HA coating exhibited a carbonate-containing composition, rod-like morphology, and nano-sized particles, all of which indicate a bone-like structure. To evaluate the bioactivity of the bone-like HA-coated Ti–5Nb–5Mo alloy, the capability of apatite formation on the alloy surface was assessed by immersion in a simulated body fluid (SBF). A dune-like apatite layer was densely deposited on the surface of the HA-coated Ti alloy after 6 h of immersion in the SBF. Notably, the ability of a Ti–5Nb–5Mo alloy subjected to sequential processing with alkali, hydrothermal, and heat treatments to form a bone-like HA nanoparticle coating was close to double that of its counterpart without an HA coating.

The internal reflux effect on dialysis through the retentate phase of a parallel-flow rectangular module is investigated. Theoretical analysis of mass transfer in the membrane devices with or without recycling is analogous to heat transfer in heat exchangers. In contrast to a device without reflux, considerable mass transfer is achievable if parallel-flow dialyzers are operated with reflux, which provides an increase in fluid velocity, resulting in a reduction in mass-transfer resistance. It is concluded that reflux can enhance mass transfer, especially for large flow rate and feed-concentration operated under high reflux ratio.

The mass transfer for the systems of dialysis with ultrafiltration in cocurrently parallel-flow rectangular membrane modules was investigated, based on mass balances with the assumption of uniform ultrafiltration flux. Considerable improvement in separation efficiency is achievable if the effect of ultrafiltration is applied, especially for the system with low mass transfer coefficient. The enhancement in separation efficiency is significantly increased with increasing ultrafiltration flux, as well as with increasing the volumetric flow rates. Furthermore, increasing the volumetric flow rate in retentate phase is more beneficial to mass transfer than increasing in dialysate phase.

The two-dimensional (2D) Nakagami image complements the ultrasound B-scan image when attempting to visualize the scatterer properties of tissues. The resolution of the Nakagami image is lower than that of the B-scan image, since the former is produced by processing the raw envelope data using a 2D sliding window with side lengths typically corresponding to three times the pulse length of the incident ultrasound. This paper proposes using three-dimensional (3D) Nakagami imaging for improving the resolution of the obtained Nakagami image and providing more complete information of scatterers for a better tissue characterization. The 3D Nakagami image is based on a voxel array composed of the Nakagami parameters constructed using a 3D sliding cube to process the 3D backscattered raw data. Experiments on phantoms with different scatterer concentrations were carried out to determine the optimal size of the sliding cube for a stable estimation of the Nakagami parameter. Tissue measurements on rat livers without and with fibrosis formation were further used to explore the practical feasibility of 3D Nakagami imaging. The results indicated that the side length of the cube used to construct the 3D Nakagami image must be at least two times the pulse length, which improved the resolution for each Nakagami image frame in the 3D Nakagami image. The results further demonstrated that the 3D Nakagami image is better than the conventional 2D Nakagami image for complementing the B-scan in detecting spatial variations in the scatterer concentration and classifying normal and fibrotic livers. This study suggests that 3D Nakagami imaging has the potential to become a new 3D quantitative imaging approach.

A handheld, battery-powered intracavity singly resonant optical parametric oscillator (IC-SRO) emitting 3.5 μm, 39 mW CW radiation is demonstrated. The lasing threshold of the IC-SRO (end-pumped by a 808 nm diode) is 120 mW.

Background The mecA gene, carried by methicillin-resistant Staphylococcus aureus (MRSA), allows the bacterium to promotes bacterial resistance to antibiotics such as methicillin, penicillin, and other penicillin-like antibiotics. Our objectives are to use a bioinformatics tool to analyze the sequence of the mecA gene, which is spread on the SCCmec genetic element, and to investigate the relationship between each mecA gene. Methods From 2008 to 2016, we collected 229 MRSA from bacteremia; we extracted DNA from the MRSA and designed specific primers to target mecA using PCR. The primer used are listed in mec A-1(5’-GGGATCATAGCGTCATTATTC-3’) and mec A-2(5’-AACGATTGTGACACGATAGCC-3’). We determined whether the mecA gene was present by using electrophoresis and then sequenced the MRSA samples in which it was present. The POWER tool was employed to analyze the mecA gene and compile a pedigree chart. Results Using the sequencing data, we created an MRSA database, and the BLAST findings demonstrated that most of the mecA genes were similar, with over 95% identified. The pedigree chart illustrates that there are four groups of mecA genes, and these groups were found to be not differentiated between the sources of the MRSA, whether from communities or hospital association infections. Conclusion Our findings indicate that even though there were four groups with ancestors in the pedigree chart, no significant difference was found between MRSA from community- and hospital-associated infections. We plan to collect more MRSA samples for analysis and investigate the differences between MRSA groups and MRSA from various geographical regions. Disclosures All authors: No reported disclosures.

A new QPM structure is proposed to improve the efficiency when the first-order QPM domain length is too short to be fabricated. SHG efficiency 4.69 times higher than the third-order QPM is experimentally demonstrated.

We proposed and experimentally demonstrated the iterative domino algorithm to optimize optical superlattice with >105 unit blocks to achieve arbitrary target phase-matching power spectrum. This scheme can achieve unprecedented overall conversion efficiency and spectral fidelity with extremely high computation efficiency.

We designed complex phase-matching spectral grid by iterative domino algorithm, and analytically proved that it can achieve the maximum conversion efficiency. Experimentally measured conversion efficiencies agreed well with the numerical results.

We propose hyperfine aperiodic optical superlattice optimized by iterative domino algorithm to achieve arbitrary discrete and continuous phase-matching power spectra. This scheme improves the record overall efficiency by 9% and handles >105 blocks.

The goal was to test whether band-limited sensory noises with adequate amplitudes, by the principle of stochastic resonance, could enhance mu and beta wave suppressions. Scalp EEG was recorded while the subject performed thumb movements in the presence of vibratory noises applied to thenar belly or thumb tip. Seven subjects without clear mu or beta wave suppression in the absence of the mechanical stimuli were recruited. The results showed that when the stimuli were applied to the thenar belly, both mu and beta wave suppressions were enhanced in a bell-shaped trend (the characteristics of stochastic resonance) in four subjects.

In-process adjustment of the blank holder force can lead to higher formability and accuracy, and better part consistency. There are many studies on the application of process control to sheet metal forming. However, process controller design has not been thoroughly addressed, and is studied in this paper. A constant gain proportional plus integral (PI) controller with approximate inverse dynamics is presented to achieve small tracking error regardless of model uncertainty and disturbances.

A quasi-phase matching (QPM) structure based on phase correction by inserting a "healing block" (HB) of length d(HB) into M regular domains of constant length d is proposed to enhance the nonlinear conversion efficiency when the first-order QPM domain length d1 is too short to be reliably fabricated. Second-harmonic conversion efficiency 4.69 times higher than that of a third-order QPM grating has been experimentally demonstrated by using HB-QPM where all the domains are longer than 1.08d1.