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The formation of heterojunction structures can effectively prevent the recombination of photogenerated electron-hole pairs in semiconductors and result in the enhancement of photoelectric properties. Using TiO

SiC/B4C composite was obtained using the reaction sintering method with Si infiltration, which exhibited excellent mechanical properties. The dynamic compressive response was investigated using a Split Hopkinson pressure bar at high strain rates ranging from 0.4×103 to 1.2×103 s-1. The results show that the dynamic strength of the SiC/B4C composite obtains a peak value at a strain rate of 1000/s, while its strain increased continuously with increasing strain rate. The dynamic loading mode of SiC/B4C composite exhibited three deformation regions, including an inelastic deformation region, rapid loading region and failure region. The dynamic failure mode of SiC/B4C composite depended upon the strain rate.

We investigate the criticality of chiral phase transition manifested in the first and second order derivatives of Dirac eigenvalue spectrum with respect to light quark mass in (2+1)-flavor lattice QCD. Simulations are performed at temperatures from about 137 MeV to 176 MeV on $N_{\tau}=8$ lattices using the highly improved staggered quarks and the tree-level improved Symanzik gauge action. The strange quark mass is fixed to its physical value $m_s^{\text{phy}}$ and the light quark mass is set to $m_s^{\text{phy}}/40$ which corresponds to a Goldstone pion mass $m_{\pi}=110$ MeV. We find that in contrast to the case at $T\simeq 205$ MeV $m_l^{-1} \partial \rho(\lambda, m_l)/\partial m_l$ is no longer equal to $\partial ^2\rho(\lambda, m_l)/\partial m_l^2$ and $\partial ^2\rho(\lambda, m_l)/\partial m_l^2$ even becomes negative at certain low temperatures. This means that as temperature getting closer to $T_c$ $\rho(\lambda, m_l)$ is no longer proportional to $m_l^2$ and thus dilute instanton gas approximation is not valid for these temperatures. We demonstrate the temperature dependence can be factored out in $\partial \rho(\lambda, m_l)/ \partial m_l$ and $\partial^2 \rho(\lambda, m_l)/ \partial m_l^2$ at $T \in [137, 153]$ MeV, and then we propose a feasible method to estimate the power $c$ given $\rho \propto m_l^{c}$., Comment: Talk presented at the 38th International Symposium on Lattice Field Theory - LATTICE2021, 26th-30th, July, 2021, Zoom/Gather@Massachusetts Institute of Technology

The asynchronous double deep Q-learning (A-DDQN) method is proposed to design the multi-mode interference (MMI) power splitters for low insertion loss and wide bandwidth from 1200 to 1650 nm wavelength range. By using A-DDQN to guide hole etchings in the interference region of MMI, the target splitting ratio (SR) can be obtained with much less CPU time (about 10 hours for one design) and more effective utilization of the computational resources in asynchronous/parallel manner. Also, this method can simplify the design by using relatively few holes to obtain the same SR with small return loss.

Wen-Yu Lin,1,2 Ching-Lan Yang,3 Wei-Ping Huang,1 Po-Chang Tseng,1,4 Hsien-Wen Kuo1,5 1Institute of Environmental and Occupational Health Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan; 2Taiwan’s Environmental Protection Agency, Taipei, Taiwan; 3Occupational Medicine Department, Far Eastern Memorial Hospital, New Taipei, Taiwan; 4Health Promotion Administration, Ministry of Health and Welfare, Taipei, Taiwan; 5Institute of Public Health, National Defense University, Taipei, TaiwanCorrespondence: Hsien-Wen Kuo, Institute of Environmental and Occupational Health Sciences, National Yang Ming Chiao Tung University, No. 155, Sec.2, Linong Street, Taipei, 112, Taiwan, Tel +886 2-28272294, Email hwkuo@ym.edu.twPurpose: Despite repetitive activities and the frequency of high workload for municipal solid waste (MSW) collectors, the risks of work-related stress on upper extremity pain are inconclusive. The objective of this study is to assess the moderation and mediation effect of effort–reward imbalance (ERI) and over-commitment (OC) on upper back and hand/wrist disorders in MSW collectors.Methods: A cross-sectional study was conducted with MSW collectors from two cities in Taiwan. Each participant was asked to anonymously fill out a structured questionnaire. Work-related stress, including ERI and OC, was assessed by a Chinese version of the Job Content Questionnaire (C-JCL). Upper back and hand/wrist disorders were assessed using the Nordic musculoskeletal questionnaire. Multivariate analysis was used to assess moderation and mediation effect of OC and ERI on upper extremity pain.Results: The moderation effect of ERI and OC on upper back and hand/wrist disorders in MSW collectors was found. Disorders were higher in the group with both ERI ≥ 1 and high OC (OR (odds ratio) = 3.25 and OR = 3.00) than in the group with ERI ≥ 1 and low OC (OR = 2.66 and OR = 1.87) and in the ERI < 1 and high OC group (OR = 2.27 and OR = 1.26). Synergy indexes were 0.77 and 1.77, respectively. Using multivariate analysis after adjusting for covariates, the mediation effect of OC was significant for the association between ERI and upper back and hand/wrist pains. The indirect effects of OC for upper back and hand/wrist pains accounted for 35% and 42%, respectively, and OC appears to mediate the relationship between ERI and upper back and hand/wrist disorders in MSW collectors.Conclusion: Work-related stress measured ERI and OC may play a role in moderating and mediating effects on upper extremity pain. Encouraging provisions of work modification and stress management is needed to mitigate the occurrence of upper extremities pain in MSW collectors.Keywords: effort–reward imbalance, ERI, over-commitment, upper back, hand/wrist disorders, municipal solid waste collectors, mediation effect

By impregnating the thermal stable TiO2 nanotubes (C/TiO2NTs) in NH4F solution with different concentrations and subsequent calcination treatment at different temperatures, C, N, F-tridoped TiO2 nanotubes (C, N, F/TiO2NTs) were prepared. XRD, XPS, TEM, TG-DTG, UV–vis and nitrogen adsorption were used to and characterize the prepared materials. The influences of dopants, calcination temperature and NH4F concentration on the catalytic performances of C, N, F/TiO2NTs under UV light and simulated sunlight were investigated by using methyl orange solution as simulant wastewater. Obtained results indicated that the C, N, F/TiO2NTs exhibited higher photocatalytic activity than the C-doped or N, F-codoped ones, and the C, N, F/TiO2NTs showed the best photocatalytic performance when they were calcinated at 300 °C and impregnated by 1 wt.% NH4F solution. The electronic density of states (DOS) analysis results implied that the C, N, F-tridoping could improve the electronic transition and narrow the band gap of anatase TiO2, and resulted in improved photocatalytic performance. The synergistic effects of the three dopants were also discussed.

Background Since the policy of “keeping trash off of the ground” in Taiwan, long-term exposure to repetitive motion in waste collection process results in high risk of upper extremity musculoskeletal disorders (UEMDs). Thus, we assessed the moderation and mediation effects of job-related stress and job support on work-related UEMDs among municipal waste collectors. Methods A cross-sectional study was conducted in two cities located at northern Taiwan during 2018–2019. 626 municipal waste collectors voluntarily participated and anonymously filled out a structured questionnaire. The moderation and mediation effects of effort-reward imbalance (ERI) and social support on UEMDs were analyzed by Haye’s Process Macro Model. Results Prevalence of UEMDs in municipal waste collectors were 43.4% for neck, 56.0% for shoulder, 24.1% for upper back, and 33.1% for hand/wrist. There was high prevalence of shoulder (72.2%), neck (48%), and upper back (30%) in female workers compared to male, most significantly in shoulders. In univariate and multivariate analysis, high ERI and low job support were significantly associated with ORs of 3.11 (95% CI:1.58–6.13) for elbow, 2.79 (95% CI:1.39–5.56) for shoulder, 3.39 (95% CI:1.64–7.00) for upper back and 3.83 (95% CI:1.98–7.41) for hand/wrist. Prevalent UEMDs were positively associated with high ERI in municipal waste collectors but negatively with job support. The moderation effects of ERI and job support on UEMDs, of which the measured synergy index exceeded one, were 18.24 for shoulder, 3.32 for elbow, and 2.45 for hand/wrist, but mediation effects were not significant. Conclusions This study found municipal waste collectors with work-related upper extremity disorders were significantly associated with work-related psychological risk factors. Therefore, waste collection cannot only to be improved by semi-automatic and automatic processes but immediate intervention programs for the reduction of psychological risk factors is needed promptly.

Thermomyces dupontii, a widely distributed thermophilic fungus, is an ideal organism for investigating the mechanism of thermophilic fungal adaptation to diverse environments. However, genetic analysis of this fungus is hindered by a lack of available and efficient gene-manipulating tools. In this study, two different Cas9 proteins from mesophilic and thermophilic bacteria, with in vivo expression of a single guide RNA (sgRNA) under the control of tRNAGly, were successfully adapted for genome editing in T. dupontii. We demonstrated the feasibility of applying these two gene editing systems to edit one or two genes in T. dupontii. The mesophilic CRISPR/Cas9 system displayed higher editing efficiency (50 to 86%) than the thermophilic CRISPR/Cas9 system (40 to 67%). However, the thermophilic CRISPR/Cas9 system was much less time-consuming than the mesophilic CRISPR/Cas9 system. Combining the CRISPR/Cas9 systems with homologous recombination, a constitutive promoter was precisely knocked in to activate a silent polyketide synthase-nonribosomal peptide synthase (PKS-NRPS) biosynthetic gene, leading to the production of extra metabolites that did not exist in the parental strains. Metabolic analysis of the generated biosynthetic gene mutants suggested that a key biosynthetic pathway existed for the biosynthesis of thermolides in T. dupontii, with the last two steps being different from those in the heterologous host Aspergillus. Further analysis suggested that these biosynthetic genes might be involved in fungal mycelial growth, conidiation, and spore germination, as well as in fungal adaptation to osmotic, oxidative, and cell wall-perturbing agents. IMPORTANCEThermomyces represents a unique ecological taxon in fungi, but a lack of flexible genetic tools has greatly hampered the study of gene function in this taxon. The biosynthesis of potent nematicidal thermolides in T. dupontii remains largely unknown. In this study, mesophilic and thermophilic CRISPR/Cas9 gene editing systems were successfully established for both disrupting and activating genes in T. dupontii. In this study, a usable thermophilic CRISPR/Cas9 gene editing system derived from bacteria was constructed in thermophilic fungi. Chemical analysis of the mutants generated by these two gene editing systems identified the key biosynthetic genes and pathway for the biosynthesis of nematocidal thermolides in T. dupontii. Phenotype analysis and chemical stress experiments revealed potential roles of secondary metabolites or their biosynthetic genes in fungal development and adaption to chemical stress conditions. These two genomic editing systems will not only accelerate investigations into the biosynthetic mechanisms of unique natural products and functions of cryptic genes in T. dupontii but also offer an example for setting up CRISPR/Cas9 systems in other thermophilic fungi.

A complex mode matching method is investigated for modeling and simulation of surface-emitting grating couplers. It is noted that the degree of accuracy for the complex modes obtained numerically plays significant role in determining the overall accuracy of the mode matching method, regardless of the number of modes used in the mode expansion. Furthermore, a reduced two-dimensional (2-D) model by using the effective index method is shown to yield highly accurate results in comparison with the full 3-D model for practical grating couplers, which allows huge saving in computational resources for performance simulation and design optimization. Finally, we employ a robust genetic algorithm (i.e., the particle swarm method) for optimization against grating period for maximum coupling efficiency to a single mode optical fiber and produces results consistent with those reported in literature.

A high uniformity and broad bandwidth Y junction optical beam splitter is proposed and analyzed in this paper based on silicon-on-insulator platform. By replacing the uniform branch with the multimode tapered branch, the bandwidth and the power uniformity of two output ports are improved prominently. Furthermore, the sensitivity to fabrication accuracy is reduced by widening the splitting angle. The simulation and the experimental results confirm that the bandwidth is larger than 100 nm, the power uniformity of two output ports is enhanced 4 dB, whereas the insertion loss is less than 0.6 dB and the return loss is larger than 26 dB, respectively.

To investigate the therapeutic effect of low-dose tadalafil on BPH-induced lower urinary tract symptoms (LUTS) complicated with ED.We randomly assigned 126 patients with BPH-induced LUTS and ED to receive daily administration of tadalafil (5 mg) plus tamsulosin hydrochloride sustained-release capsules (0.2 mg) (treatment group Ⅰ ［T-Ⅰ］, n = 42), tadalafil (5 mg) only (treatment group Ⅱ ［T-Ⅱ］, n = 42) or placebo (control group, n = 42), all for 12 weeks. Before and after 6 and 12 weeks of medication, and at 4 and 8 weeks after drug withdrawal, we recorded and compared the IPSS sub-item scores in the voiding stage and urinary storage symptoms, total IPSS, IIEF-5 scores, and the frequency of sexual activities among the three groups of patients.As for the IPSS sub-item scores in the voiding stage symptoms, T-Ⅰ showed statistically significant differences between any two of the five time points (P0.05), but not T-Ⅱ between the baseline and 6-week medication or 8-week withdrawal (P0.05), or between 6-week medication and 8-week withdrawal (P0.05), nor did the control group among the five time points (P0.05). Statistically significant differences were observed between any two of the three groups at 12 weeks of medication and 4 weeks after drug withdrawal (P0.05), but not between the T-Ⅱ and control groups at 6 weeks of medication or 8 weeks after withdrawal (P0.05). As to the IPSS sub-item scores in the urinary storage symptoms, there were significant differences between any two time points in T-Ⅰ and T-Ⅱ (P0.05), but not in the control (P0.05), nor between T-Ⅰ and T-Ⅱ at 6 or 12 weeks of medication or at 4 or 8 weeks after drug withdrawal (P0.05). With regard to the total IPSS, statistically significant differences were found between any two of the three groups at 6 and 12 weeks of medication and 4 and 8 weeks after drug withdrawal (P0.05), but not between 6-week medication and 8-week withdrawal in T-Ⅰ or T-Ⅱ (P0.05), nor among the five time points in the control group (P0.05). Concerning the IIEF-5 scores, there was no significant difference in the frequency of sexual activities between the three groups （Ｐ0.05）.There were statistically significant differences between any two of the three groups at 6 weeks of medication and 8 weeks after drug withdrawal (Ｐ0.05), but not between 6-week medication and 4- or 8-week withdrawal (P0.05) or between 4- and 8-week withdrawal (P0.05) in T-Ⅰ, nor between 6-week medication and 8-week withdrawal in T-Ⅱ (P0.05) or among the five time points in the control (P0.05), nor between T-Ⅰ and T-Ⅱ at 12 weeks of medication (P0.05) or 4 weeks after drug withdrawal (P0.05).Daily administration of tadalafil at 5 mg can effectively improve the IPSS sub-item scores in the urinary storage symptoms and IIEF-5 scores, with a persistent effect after withdrawal similar to that of its combination with other drugs, and therefore can be recommended for the treatment of BPH-induced LUTS complicated with ED.

A parity-time symmetric vertical Bragg reflection waveguide structure is proposed and analyzed for realizing single-mode operation of a laser diode. Impact of the key design parameters on laser performance are investigated for the purpose of achieving high side-mode suppression ratio and high injection slope efficiency. Our studies indicate that an electrically pumped edge-emitting single-mode laser is possible with proper design. Such lasers exhibit a number of highly desirable and in some cases unique characteristics, such as high-modulation bandwidth, high transverse gain, and high confinement of optical field in the low-effective index Fabry–Perot cavity.

Three lanthanide–nitronyl nitroxide radical complexes [Ln(hfac)3(NIT-2Br-4Py)]2 (Ln(III) = Gd (1), Tb (2), Dy (3); hfac = hexafluoroacetylacetonate; NIT-2Br-4Py = 2-(2′-bromo-4′-pyridyl)-(4,4,5,5-tetramethyl-3-oxylimidazoline-1-oxide)) have been synthesized. Single crystal X-ray diffraction analysis reveals that complexes 1–3 are isomorphous in which NIT-2Br-4Py acts as a bridging ligand linking two Ln(III) ions through the nitrogen atom of pyridine ring and the oxygen atom of N O group to form a four-spin system. The magnetic studies show that ferromagnetic coupling interaction between Ln(III) ions and nitronyl nitroxide radical. Moreover, ac measurements show that Tb(III) complex exhibits frequency-dependent signals at low temperature.