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The incident pump beam waist-dependent pulse energy generation in Nd:YAG/Cr4+:YAG composite crystal passively Q-switched microchip laser has been investigated experimentally and theoretically by moving the Nd:YAG/Cr4+:YAG composite crystal along the pump beam direction. Highest pulse energy of 0.4 mJ has been generated when the Nd:YAG/Cr4+:YAG composite crystal is moved about 6 mm away from the focused pump beam waist. Laser pulses with pulse width of 1.7 ns and peak power of over 235 kW have been achieved. The theoretically calculated effective laser beam area at different positions of Nd:YAG/Cr4+:YAG composite crystal along the pump beam direction is in good agreement with the experimental results. The highest peak power can be generated by adjusting the pump beam waist incident on the Nd:YAG/Cr4+:YAG composite crystal to optimize the effective laser beam area in passively Q-switched microchip laser. [ABSTRACT FROM AUTHOR]

BACKGROUND: Prognosis of stage IIIA N2 non-small cell lung cancer (NSCLC) remains poor despite the changes in therapeutic strategies. OBJECTIVES: To assess long term results of neo adjuvant therapy followed by surgery for patients with stage IIIA N2 NSCLC and to analyze factors influencing survival. MATERIALS AND METHODS: The methods adopted include: Retrospective review of medical records of 91 patients with stage IIIA N2 NSCLC, who received neo adjuvant therapy followed by surgery; collection of information on demographic information, staging procedure, preoperative therapy, clinical response, type of resection, pathologic response of tumor, status of lymph nodes and adjuvant chemotherapy; survival analysis by Kaplan- Meier and calculation of prognostic factors using log-rank and Cox regression model. RESULTS: All patients received a platinum-based chemotherapy and 23 (29.1%) had an associated radiotherapy. Eighty four patients underwent thoracotomy. Median survival was 26 months (95%CI, 22.6-30.8 months) with three and five year survival rates of 31.6 and 20.9%, respectively. Prognostic factors for survival on univariate analysis was clinical response (P = 0.032), complete resection (P = 0.002), pathologic tumor response (P < 0.001), and lymph nodal down staging (P = 0.001). Multivariate analyses identified complete resection, pathologic tumor response and lymph nodal down staging as independent prognostic factors. CONCLUSION: Survival of patients with stage IIIA N2 NSCLC who received neo adjuvant therapy is significantly influenced by clinical response, complete resection, pathologic tumor response, and lymph nodal down staging. These results can be helpful in guiding standard clinical practice and evaluating the outcome of neo adjuvant therapy followed by surgery in patients with stage IIIA N2 NSCLC. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to evaluate the efficacy of cisplatin plus vinorelbine as a regimen of neoadjuvant chemotherapy on the improvement of surgical resectability and survival in Chinese patients with stage IIIA non-small cell lung cancer (NSCLC). Methods: Fifty-six patients with stage IIIA NSCLC were randomly assigned to undergo either surgery preceded by two cycles of chemotherapy with cisplatin plus vinorelbine (the neoadjuvant chemotherapy arm) or immediate surgery (the primary surgery arm). The patients who had a complete resection received two to four cycles of chemotherapy, and those with incomplete resection received radiotherapy followed by two cycles of chemotherapy after surgery. Results: The overall response rate to neoadjuvant chemotherapy was 53.6%, with a complete response of 7.1%. A pathological complete response was seen in two patients (8%). The complete resection rates were 78.6% in the neoadjuvant chemotherapy arm and 60.7% in the primary surgery arm. The median overall survival and median disease-free survival was 30 months and 24 months, respectively, in the neoadjuvant chemotherapy arm as compared to 16 months and 11 months in the primary surgery arm ( P = 0.04 and P = 0.048). The 3-year and 5-year survival rate was 49.7% and 31.9%, respectively, for the neoadjuvant chemotherapy arm and 29.2% and 3.6% for the primary surgery arm. Conclusion: Neoadjuvant chemotherapy with cisplatin plus vinorelbine regimen is effective and tolerable and can improve the overall survival and disease-free survival time in Chinese patients with stage IIIA NSCLC. [ABSTRACT FROM AUTHOR]

In this paper the laser activities of a diode-pumped Yb:LuAG ceramic which was prepared by the solid-state reactive sintering method were reported. The maximum output power was 1.86 W in the continuous wave (CW) laser operation, corresponding to a slope efficiency of 53.6%. The CW laser could be tuned from 1030 to 1096 nm by inserting a prism in the cavity. With the assist of a semiconductor saturable absorber mirror (SESAM), passive mode-locking was realized, delivering sub-picosecond pulses with 933 fs duration and an average power of 532 mW at a repetition rate of 90.35 MHz. [ABSTRACT FROM AUTHOR]

We report a cw Tm:YAP laser resonantly pumped Ho:LuVO4 laser in passively Q-switched (PQS) mode with Cr2+:ZnS as a saturable absorber (SA). The influence of different transmittances of the output coupler on laser output performance is analyzed. With T = 50%, the maximum PQS average output power of 2.3 W is obtained, corresponding to the slope efficiency and the optical–optical conversion efficiency are 35.1% and 19.8%, respectively. Also, the minimum pulse width of 100 ns is achieved at the maximum pulse repetition frequency of 34.2 kHz. When the maximum cw output power is 2.7 W, the beam quality factor of the horizontal direction Mx2 = 1.04 and the vertical direction My2 = 1.10 are obtained. In addition, the central wavelength of the laser output remains to be 2057.5 nm with the output coupler transmittances of 50% and 60% in both cw and PQS operations. The results show that the Cr2+:ZnS can be used as an SA in a Ho:LuVO4 laser around 2-μm wavelength. [ABSTRACT FROM AUTHOR]

Output performance of a continuous-wave Tm:YAP laser pumped passively Q-switched Ho:YLF laser is demonstrated with a polycrystalline Cr2+:ZnS as the saturable absorber. We compare the experimental results at the three different distances L of the polycrystalline Cr2+:ZnS saturable absorber to the output coupler. The pulse width almost remains constant for different L, when the incident pump power is changed in the range of 7.9–27.1 W. The shortest pulse duration of 33.3 ns for L = 105 mm and the highest average output power of 6.8 W for L = 5 mm are obtained at the incident pump power of 27.1 W. The output wavelength of the passively Q-switched laser shifts to 2045.2 nm from 2064.7 nm in the cw operation. The beam quality factor of M2 is 1.2. [ABSTRACT FROM AUTHOR]

The pollution of surface waters by pharmaceuticals and personal care products (PPCPs) has aroused widespread concern. Constructed wetlands (CWs) have outstanding advantages in the removal of PPCPs; however, few studies have focused on the interaction of different types of PPCPs in CWs. In this study, two typical PPCPs[broad-spectrum antimicrobial agents triclosan (TCS) and non-steroidal anti-inflammatory drug diclofenac (DCF)] were selected as target pollutants and their removal behavior in subsurface flow CWs was analyzed. The effects of different seasons and influent conditions (i.e., single and combined addition of TCS and DCF) on removal efficiency was also examined. The main parameters of the CW system were as follows:the up-flow subsurface CW had a hydraulic load of 0.20 m·d -1 and a hydraulic residence time of 3 d with a continuous flow inlet. The initial influent concentration of PPCPs was 80 g·L -1 for TCS and 25 g·L -1 for DCF. The results showed that the average removal efficiencies for TCS and DCF in summer (91.72% and 85.86%, respectively) were significantly higher than in winter (52.88% and 32.47%, respectively). Independent sample t -tests confirmed that there was no significant difference in the removal efficiency of TCS and DCF under the different influent conditions (single and combined addition). The degradation products of TCS and DCF were also no different between the influent systems, and the representative degradation products of TCS were not detected in all systems. The main degradation products of DCF in the different systems were 3,5-dichlorobenzoic acid and m-dichlorobenzene. The two studied PPCPs showed no significant antagonism and competition effects at trace levels.

Tip-enhanced Raman spectroscopy can provide molecular fingerprint information with ultrahigh spatial resolution, but the tip will be easily contaminated, thus leading to artifacts. It also remains a great challenge to establish tip-enhanced fluorescence because of the quenching resulting from the proximity of the metal tip. Herein, we report shell-isolated tip-enhanced Raman and fluorescence spectroscopies by employing ultrathin shell-isolated tips fabricated by atomic layer deposition. Such shell-isolated tips not only show outstanding electromagnetic field enhancement in TERS but also exclude interference by contaminants, thus greatly promoting applications in solution. Tip-enhanced fluorescence has also been achieved using these shell-isolated tips, with enhancement factors of up to 1.7×10 3 , consistent with theoretical simulations. Furthermore, tip-enhanced Raman and fluorescence signals are acquired simultaneously, and their relative intensities can be manipulated by changing the shell thickness. This work opens a new avenue for ultrahigh resolution surface analysis using plasmon-enhanced spectroscopies., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)