Unravelling hidden threats of water disinfection: Toxicity evaluation and toxic products identification during diclofenac degradation.

Diclofenac (DCF) is a widely-used nonsteroidal anti-inflammatory drug that is routinely found in surface water bodies. While ozonation and ultraviolet (UV) radiation are commonly employed as disinfection methods in water treatment processes, the degradation of DCF in these processes occurs due to the strong oxidizing activity of the reactive oxygen species produced during both ozonation and UV radiation. Despite extensive studies reporting the removal and transformation of DCF through ozone and UV treatments, the potential hidden hazards of toxicity arising from these processes as well as the identification of the toxic transformation products have often been overlooked. In this study, various toxicities including microtoxicity, genotoxicity and antiestrogenicity were evaluated using multiple in-vitro bioassays. The transformation products were identified via ultra-performance liquid chromatography equipped with mass spectrometry (UPLC-MS). Correlation analysis was employed to gain deeper insight into the contributions of degradation products to overall toxicity. The results revealed that DCF possessed significant genotoxic and antiestrogenic effects, but displayed minimal microtoxicity. Microtoxic products such as those containing carbazole were generated during DCF degradation with ozone, UVA and UVC. Antiestrogenic products with dichloroaniline structures were observed in DCF ozonation but not in photodegradation by UVA and UVC. These findings highlighted the hidden risks associated with the disinfection of water containing micropollutants such as DCF.

Correlation analysis between thromboelastography and liver injury related indexes in patients with heat stroke / 中国热带医学

@#Abstract: Objective To analyze the correlation between the thromboelastography (TEG) indexes and the indexes related to liver injury in patients with heat stroke, and explore the diagnostic value of TEG indexes for liver injury in patients with heat stroke. Methods A total of 95 patients with exertional heat stroke (EHS) admitted to 924 Hospital of the Joint Service Support Force of the People's Liberation Army of China from August 2020 to July 22 were selected, and divided into a non-liver injury group (55 cases) and a liver injury group (40 cases) according to whether there was liver injury. TEG instrument was used for the detection of thromboelastography to record the TEG parameters, including reaction time (R), agglutination time (K), α angle, maximum amplitude (MA value), and coagulation complex index (CI). The levels of glutamic transaminase (AST), alanine aminotransferase (ALT), total bilirubin (TBil), albumin (ALB) were detected by automatic biochemical analyzer. Pearson's method was applied to analyze the correlation between thromboelastography indexes R, K, α angle, CI and liver function indexes AST, ALT, TBil, ALB in patients with heat stroke after liver injury. Receiver operating characteristic curve (ROC) was applied to analyze the predictive value of thromboelastography indexes R, K, α angle, CI and combined detection for liver injury in patients with heat stroke. Results Compared with the non-liver injury group, the AST, ALT and TBil levels in patients with heat stroke in the liver injury group were higher (t=26.174, 16.923, 18.414, P<0.05), while the ALB level was lower (t=24.596, P<0.05); compared with the non-liver injury group, the R and K of patients with heat stroke in the liver injury group were higher (t=58.014, 52.862, P<0.05), and the α angle and CI were lower (t=46.853, 60.717, P<0.05); R was positively correlated with AST and ALT (r=0.532, 0.610, P<0.001), and negatively correlated with ALB (r=-0.551, P<0.001) in patients with heat stroke complicated with liver injury; K was positively correlated with AST, ALT and TBil (r=0.661, 0.531, 0.504, P<0.001); α angle was negatively correlated with AST and ALT (r=-0.473, -0.448, P<0.01), and positively correlated with ALB (r=0.539, P<0.001); CI was negatively correlated with AST, ALT and TBil (r=-0.458, -0.505, -0.549, P<0.001); the area under the curve (AUC) of thromboelastography indexes R, K, α angle and CI in predicting liver injury in patients with heat stroke was 0.807 (sensitivity of 70.0%, specificity of 81.6%), 0.831 (sensitivity of 77.5%, specificity of 85.5%), 0.747 (sensitivity of 67.5%, specificity of 74.5%), and 0.788 (sensitivity of 77.5%, specificity of 83.6%), respectively. The AUC of combined detection to predict liver injury in patients with heat stroke was 0.967 (sensitivity of 92.5%, specificity of 91.9%). Conclusions The thromboelastography indexes are correlated with the indexes related to liver injury in patients with heat stroke, and the thromboelastography indexes are helpful to diagnose liver injury in patients with heat stroke.

Rapid detection for rabbit-derived dermatophytes using microsatellite-primed polymerase chain reaction.

A method exhibiting high sensitivity, specificity and rapidity to detect pathogenic dermatophytes was developed using microsatellite-primed polymerase chain reaction (PCR) in combination with a clustering method. The DNA fragments of Trichophyton mentagrophyton, Microsporum gypseum and Microsporum canis were amplified by using the primer (GACA)4 to detect the DNA polymorphism fingerprints. Twenty-one clinical strains identified as T. mentagrophyton, M. gypseum or M. canis by morphological methods were distinguished according to the differences of standard stains' bands combined with NTSYS-pc2.10 software. The results showed that there were obvious and direct differences in the bands of the three pathogenic dermatophytes, and the similarity of isolated strains and standard strains were above 90%, in line with the results of morphological identification. The method is more accurate, rapid and simple, which is meaningful for the clinical diagnosis and epidemic research of the dermatophytes.

39.1 µJ picosecond ultraviolet pulses at 355 nm with 1 MHz repeat rate.

Based on our reliable high-power picosecond laser source with high beam qualities, we designed a compact and efficient third harmonic generation scheme by cascading a frequency doubling and a sum frequency generation using LBO as the nonlinear material. A maximum output of 39.1 W with a repeat rate of 1 MHz at 355 nm was obtained, which implied a pulse energy of 39.1 µJ, which was the highest picosecond UV pulse energy with an all-solid-state setup so far. The total conversion efficiency from infrared to UV was up to 46%. And the output UV has excellent beam qualities with an M-square factor less than 1.1.

Theoretical and experimental research on the polarization-coupled-input Raman oscillator.

We present a polarization-coupled-input Raman oscillator, which is pumped by a 532 nm Q-switched hybrid resonator Nd:YVO(4) slab second harmonic generation laser. By the polarization-coupled method, the dichroic mirror is avoided and more than 98% of the 532 nm pump energy can be coupled into the Raman oscillator. Theoretical calculations and the experimental results show that the second Stokes effect is dramatically suppressed. With this method, the pure 559 nm (P(532)/P(559)<0.7% and P(589)/P(559)<0.1%) laser output can be achieved.

Diode end-pumped high-power Q-switched double Nd:YAG slab laser and its efficient near-field second-harmonic generation.

We reported on an all-solid-state double Nd:YAG slab laser. The laser was based on two diode end-pumped Nd:YAG slabs and a stable-unstable hybrid resonator. A cw output of 189 W and an average Q-switched output of 169 W at 10 kHz with an M(2) factor of 1.5 in the slow direction and 1.7 in the fast direction were obtained. We demonstrated efficient near-field frequency doubling by imaging the one-dimensional top-hat near-field to a lithium triborate frequency doubler. We obtained 93 W green light at 10 kHz with a pulse width of 10.7 ns. The efficiency of second-harmonic generation was up to 57%.

High efficiency 165 W near-diffraction-limited Nd:YVO(4) slab oscillator pumped at 880 nm.

We demonstrate a compact, efficient Nd:YVO(4) stable-unstable hybrid slab oscillator that was partially end pumped at 880 nm. A maximum output power of 165 W at 1064 nm was obtained with an optical-to-optical efficiency from absorbed pump power to laser output of up to 60% and a slope efficiency of up to 66%. The beam propagation factors M(2) were 1.7 in the stable direction and 1.4 in the unstable direction without sidelobes.

Diode-end-pumped double Nd:YLF slab laser with high energy, short pulse width, and diffraction-limited quality.

We have developed a novel electro-optic Q-switched diode-end-pumped solid slab laser that combines high energy, short pulse width, high repetition rates, and diffraction-limited beam quality. With two partially end-pumped Nd:YLF slabs and a 100 mm long off-axis positive branch stable-unstable oscillator, 24.2 mJ, 7.1 ns electro-optic Q-switched pulse at 1 kHz repetition rate with a beam quality of M(x)(2)=1.4 and M(y)(2)=1.3 was generated. The peak power reached 3.5 MW. Efficient external second-harmonic generation was achieved by use of lithium triborate with low peak-power intensity.

Near-diffraction-limited green source by frequency doubling of a diode-stack pumped Q-switched Nd:YAG slab oscillator-amplifier system.

A near-diffraction-limited, stable, 18 mJ green source with a pulse width of 16.7 ns was generated at a 1 kHz repetition rate by frequency doubling of diode stacks end-pumped electro-optically Q-switched slab Nd:YAG oscillator-amplifier system. The pump to green optical conversion efficiency was 10.7%. At the output energy of 15 mJ at 532 nm, the M2 factors were 1.3 and 1.7 in the unstable and stable directions, respectively. The energy pulse stability was approximately 0.8%.

Monolithic Nd:YVO4 slab oscillator-amplifier.

We report on a compact, efficient, and reliable monolithic Nd:YVO(4) slab oscillator-amplifier with an output power of 29.3 W in cw operation and an optical-to-optical efficiency of 24%. In electro-optically Q-switched operation, 28.8 W of average power at a repetition rate of 100 kHz with a pulse width of 15 ns was measured. The RMS stability of the pulse energy is better than 1.7%. The beam quality M(2) in both cw and pulse models was under 1.3.

Diode-pumped efficient slab laser with two Nd:YLF crystals and second-harmonic generation by slab LBO.

We demonstrate a diode-pumped electro-optical Q-switched slab laser with a high optical efficiency, high pulse energy, and short pulse width with two Nd:YLF crystals inside one resonator. The single compact slab resonator can generate a 1D top-hat beam at both the far field and the near field. With a slab-geometry-design lithium triborate (LBO) crystal, efficient critical phase-matching second-harmonic generation for a 1D top-hat beam with multiple transverse modes is achieved.

Diode-end-pumped electro-optically Q-switched Nd:YLF slab laser.

We report a very compact Nd:YLF slab laser that is end pumped by a quasi-continuous-wave diode stack. A hybrid resonator is used to generate high output power in a near-diffraction-limited beam (i.e., a beam propogation M2 factor of less than 1.2). A pulse energy of 14.3 mJ was obtained with a pulse width of 8.5 ns at a repetition rate of 500 Hz, which corresponds to a Q-switched peak power of 1.68 MW.

Diode-end-pumped, electro-optically Q-switched Nd:YVO4 slab laser and its second-harmonic generation.

We describe the operation of a near-diffraction-limited, 1,064-nm electro-optically Q-switched Nd:YVO4 slab laser that is end pumped by laser-diode stacks and its efficient second-harmonic generation by using a lithium triborate (LBO) crystal. The energy per pulse of 3.6 and 0.8 mJ and pulse widths of 5 and 13.5 ns were obtained at repetition of 5 and 40 kHz, respectively. With a LBO crystal, a maximum output power of 15.6 W at 532 nm was obtained at the repetition rate of 40 kHz, the corresponding conversion efficiency was 60%, and the pulse width was 11.3 ns. At 10 kHz, the pulse energy of 532 nm was 1.2 mJ, and the pulse width was 5 ns.

Electro-optically Q-switched Nd:YVO4 slab laser with a high repetition rate and a short pulse width.

We report on a compact and highly efficient diode-end-pumped TEM00 Nd:YVO4 slab laser with an output power of 103 W and beam quality M2 < or = 1.5. The optical-to-optical efficiency was 41.5%. In electro-optically Q-switched operation, 83 W of average power at a pulse-repetition rate of 50 kHz with a pulse length of 11.3 ns was obtained. At a pulse-repetition rate of 10 kHz, 5.6 mJ of pulse energy, and 870 kW of peak power were measured.