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To develop a novel ultrasound (US) plane to diagnose palatine tonsillar hypertrophy objectively in children.Tonsillar ultrasonography of children (age 2-14 years) who had a clinical diagnosis of tonsillar hypertrophy or not were analyzed retrospectively. Clinical data (including gender, age, body mass index (BMI)), and volume (V) of tonsils measured by the US, were recorded. Furthermore, we found a new US plane to diagnose tonsillar hypertrophy and named it the submental oblique cross-section. In this plane, diameters of the left tonsil, right tonsil, and central oropharynx were designated as T1, T2, and O. Then, we calculated the ratio by the formula (T1 + T2)/O.A total of 172 cases (85 hypertrophy and 87 non-hypertrophy) were included in this study. There were no significant differences in gender (P = .844), age (P = .666), and BMI (P = .089) between the groups. In the non-hypertrophy group, the V of both sides had a positive linear correlation with age or BMI. In contrast, there was no linear correlation between ratio and age or BMI. The area under the curve (AUC) of ratio and V was 0.970 (95%CI: 0.947-0.993) and 0.835 (95%CI: 0.778-0.893) by receiver operating characteristic (ROC) analysis, respectively. The optimal cutoff value of ratio for diagnosis of tonsillar hypertrophy was 2.293 (sensitivity = 88.2%, specificity = 95.4%).We established a new US section to evaluate tonsillar hypertrophy. This approach could be easily acquired and provide a reference value to guide clinical practice.

After being collected from the wastewater treatment system, duckweed biomass which is rich in starch and protein has the potential to be converted to valuable chemicals. This study aimed to establish a fermentation process for bioconversion of duckweed biomass derived from wastewater treatment to lactic acid (LA) by Lactobacillus casei. The Lactobacillus casei CICC 23184 showed the best LA production ability in duckweed-based medium among five strains. Simultaneous saccharification and fermentation (SSF) and separated hydrolysis and fermentation (SHF) were conducted, and the SSF had better performance even with lower enzyme dosage. No extra nitrogen source needed supplying into duckweed-based media. In batch fermentation, biomass loading of 220 g kg−1 was optimal with LA concentration of 72.51 ± 2.81 g kg−1 and yield of 0.35 ± 0.01 g g−1dry biomass. The highest LA concentration (100.36 ± 3.31 g kg−1), yield (0.38 ± 0.01 g g−1dry biomass), and productivity (2.09 ± 0.07 g kg−1 h−1) were obtained through fed-batch SSF at a final biomass loading of 260 g kg−1. This study demonstrated that it is feasible to utilize duckweed biomass as feedstock to produce LA through fermentation, and a fed-batch SSF at high-biomass loading was successfully established. This study provides a novel strategy for sustainable recycling of duckweed biomass derived from wastewater treatment.

A heterotrophic nitrifying aerobic denitrifying (HN-AD) strain HY-1 with excellent capacity, identified as Paracoccus denitrificans, was isolated from activated sludge. HY-1 was capable of removing NH

Cyanobacterial blooms impose a substantial risk for submerged macrophytes in aquatic environments. This study investigated the cellular and transcriptomic responses of Vallisneria natans to microcystin-LR (MCLR) exposure, as well as abscisic acid (ABA) and strigolactone (SL), which are the major compounds in signaling networks that regulate plant defense. The results revealed that MCLR significantly (p0.05) decreased the photosynthetic pigments and significantly (p0.05) increased the contents of the ABA and SL stress-related phytohormones under MCLR stress. Related genes involved in the photosynthetic pathways were down-regulated, including psbO, psbP, psbQ and psbR. In the SL biosynthetic pathway of roots under MCLR stress, related genes, such as D27 and CCD7, were down-regulated, while the CCD8 and MAX1 genes were up-regulated. In the ABA synthetic pathway, the genes LUT5, ZEP, NCED, ABA2 and AAO3 were up-regulated. Furthermore, a reduction in the content of SL enriched ABA after 3 days under MCLR stress. The potential molecular mechanism of the interactions between SL and ABA were confirmed with the relative up- and down-regulated genes in the pathway, and ABA could play a major role in plant physiology under MCLR stress. This study provides valuable information to understand the stress-related mechanisms of response of submerged macrophytes to cyanobacterial blooms.

Carriers strengthened duckweed treatment system (CDW), duckweed treatment system (DW) and water hyacinth treatment system (WH) were developed to treat rural wastewater in Dianchi Lake basin. Results showed that adding microbial carrier did not affect the growth and biomass components of duckweed. The following features were discovered in the CDW system. First, the NO3--N and TN removal efficiencies were the highest among three systems, reaching 80.02% and 56.42%, respectively. Secondly, Illumina sequencing revealed the highest microbial diversity. Thirdly, a distinct succession of microbial community was observed. Rhodobacter, Bacteria vadinCA02, C39 and Flavobacterium dominated in the start-up stage, and contributed to biofilm formation and pollutants degradation. Acinetobacter, Planctomyces and Methylibium significantly increased in the stable stage, and contributed to nitrogen removal. Finally, highly abundant plant growth-promoting bacteria were found. Comprehensive analysis indicated that the functional bacteria community was closely related to the pollutant removals, plant growth and system operating status.

Duckweeds are traditionally used as a plant protein source in some Southeast Asian countries. In this study, we first obtained a high-protein strain (Wolffia arrhiza 7678a) under artificial conditions and determined its protein content in 50.89% of dry weight. More importantly, we further investigated its nutritional properties. The digestible indispensable amino acids score (DIAAS) reached 0.75, indicating the good protein quality of W. arrhiza. The proportion of unsaturated fatty acids in total fatty acids (TFA) was 70.85%, and three main fatty acids (palmitic acid, linoleic acid, α-linolenic acid) accounted for 89.7% of TFA. Compared with the conventional crops, it had much higher contents of total phenolics and flavonoids and showed higher antioxidant activities. Also, the low concentrations of antinutritional factors could make the nutrients of W. arrhiza easily absorbed. Therefore, W. arrhiza showed a great potential value for human food.

The polyculture of different duckweed species is likely to integrate their advantages in removing pollutants and starch accumulation. Here, pilot-scale comparisons of three duckweed species (Spirodela polyrhiza K1, Lemna minor K2 and Landoltia punctata K3) in monoculture and polyculture were investigated. Results showed that the TN (total nitrogen) and TP (total phosphorus) in wastewater decreased from 6.0 and 0.56 mg L−1 to below 0.5 and 0.1 mg L−1, respectively. Namely, the water quality improved to Grade II under the Chinese standard. The highest TN and TP removal efficiencies were found to be 99.1% and 90.8% in the polyculture. Besides, the starch content of S. polyrhiza K1, L. minor K2, L. punctata K3 and the polyculture reached 24.8%, 32.3%, 39.3% and 36.3%, respectively. Accordingly, their average starch accumulation rates were 1.65, 2.15, 3.11 and 2.72 g m−2 d−1, respectively. Our results suggested that L. punctata K3 was a promising energy feedstock due to it having the highest starch production. The advantages of different duckweed species were investigated. In the polyculture, the pollutants were efficiently removed from wastewater, with a high starch accumulation. This study supplies a new insight into the application of duckweed in eutrophic water advanced treatment coupled with starch production.

The fungal community and the population of 16S rRNA, 18S rRNA and cellulose-degrading genes during the 30-day composting process of Chinese medicinal herbal residues were investigated using Illumina MiSeq and quantitative real-time PCR. An obvious succession of fungal communities occurred during the composting process. Unidentified fungi predominated in the raw materials. As composting progressed, Ascomycota became the most dominant phylum, with Aspergillus being the most dominant genus, and Aspergillus fumigatus making up 99.65% of that genus. Because of the inoculation of cellulolytic fungi in the mature stage, the cellulose degradation rate in inoculation groups was faster and the relative abundances of Aspergillus and the glycoside hydrolase family 7 genes were significantly higher than those in the control groups. These indicated that the fungal inoculants facilitated the degradation of cellulose, increased cellulolytic fungi and optimized the community structure.

Lemnaceae (duckweed) is the smallest flowering plant, consisting of 5 genera and 37 species. It is a potential source for the production of biomass rich in starch, protein, flavonoids, and other high-value compounds. Also, it is deemed as a model for aquatic plants due to its small genome size. The biochemical and physiological features of duckweed have been studied for many years, while the molecular analysis at omics level was not studied until recently. To date, the genomes of three duckweed species, Spirodela polyrhiza, Lemna minor, and Lemna gibba, were sequenced and annotated. The expression profiles of duckweed were also studied at transcriptome level under various cultivation conditions. However, research on duckweed proteomics lags behind. The proteome analysis gives a precise estimate of gene expression and function. It plays an important role in mechanism elucidation of biochemical and physiological features of duckweed. Here, we review the progress of proteomic research of duckweed, to improve our insight into the mechanism of starch accumulation by duckweed at proteome level.

Phosphorus is an essential element for plant growth and reproduction. This study aimed to investigate the metabolic response, growth, and starch accumulation mechanisms in duckweed strain, Landoltia punctata 0202, under phosphate starvation. The results revealed that, under phosphate starvation, the total phosphorus in L. punctata 0202 decreased, while total carbon increased. After 15 days of phosphate starvation, biomass yield increased from 12.64 to123.87 g m−2, while phosphorus utilization efficiency increased to 761.78 g g−1. The starch content accumulated from 2.14 to 38.05 % by Day 15, and the starch yield reached 47.14 g m−2 on Day 15. Furthermore, biochemical and transcriptome analysis results showed a sharp increase in ADP-glucose pyrophosphorylase activity and the expression of genes encoding granule starch synthase and starch branching enzyme under phosphate starvation supported starch accumulation in L. punctata 0202. Additionally, large amounts of high-affinity phosphate transporters, vacuolar phosphate efflux transporters, and purple acid phosphatases were expressed. In summary, based on multi-level physiological and biochemical results, transcriptomic analyses, and preliminary analysis of the phosphate efflux transporter protein function, this study revealed the mechanism of starch accumulation induced by phosphate starvation and high-efficiency phosphate recycling in L. punctata. These findings offer an important foundation and insight into the molecular mechanisms influencing the uptake and utilization of nutrients. The screened functional genes exhibited potential for crop improvements under stressful environmental conditions.

Piggery wastewater with high concentration of carbon and nitrogen could be effectively treated by aerobic granular sludge (AGS). However, the underlying mechanisms responsible for simultaneous nitrogen and carbon removal have not been well revealed. Here we conducted a combined analysis of microbial community, denitrification genes and mathematical model calculation to illuminate the metabolic process of this AGS. The relative abundances of the dominant microorganisms were Comamonadaceae (accounting for 24.79%, including Comamonadaceae-un, Ideonella, Comamonas and Variovorax), Saccharibacteria-un (6.07%), Ideonella (5.51%), Luteimonas (4.81%), Bacteroidales (4.09%), Niabella (3.95%), Fillimonas (3.53%), Thauera (3.51%) and Pseudoxanthomonas (3.44%). The dominant microorganisms in the AGS mainly had the potentials of heterotrophic nitrification, aerobic denitrification, organic macromolecule degradation, organics storage and granule stability maintaining. Interestingly, only 0.145% of the communities were found as autotrophic nitrifiers. Moreover, the quantitative analysis of denitrification genes showed the abundance of napA gene was significantly higher than that of narG gene, suggesting that aerobic and anoxic denitrification process coexisted in the AGS, and the former was dominant. Furthermore, the calculations based on mathematical model were used to deduce the nitrification, denitrification and organic matter utilization process in one running cycle of the AGS. The results also indicated that the rapid organic substrates storage in the feast phase might resist the impact of high strength wastewater, and provide carbon and energy sources in the famine phase. Together, our study elucidated the nitrogen and carbon removal process of the AGS treating piggery wastewater with high concentrations.

Aerobic composting of cellulosic biomass is difficult to start at low temperatures. Especially, the effect of microbial inoculants on the initiation of aerobic composting of cellulosic material at low temperature and the succession of microbial community is still poorly defined. In this study, the aerobic composting of mushroom residue and wood chips successfully started at 3–11 °C by inoculating the microbial agents (including bacteria and fungi) for cellulose degradation and low temperature adaptation. It was found that the inoculum was beneficial for the heating of the compost pile, starting of the aerobic composting process and the degradation of cellulose. The thermophilic stage of inoculation group lasted for 13 days and 8 days longer than that of control group. The degradation efficiencies of hemicellulose and cellulose in inoculation group and control group were 37.50% and 27.30%, while the degradation efficiencies of cellulose were 21.29% and 16.18%, respectively. Furthermore, the results of high-throughput sequencing revealed that inoculation of microbial agents was beneficial to the optimization of community structure and the conversion of cellulose substrate. In addition, the inoculated strains of Aspergillus, Penicillium, Bacillus and Streptomyces might play active roles in the composting process, especially in the set-up and thermophilic stage of the composting.

The Activated Sludge Model No. 3 (ASM3) was modified by considering the simultaneous storage and growth, heterotrophic nitrification and aerobic denitrification processes. The model was used to simulate the biological process of aerobic granular sludge (AGS) treating high COD and nitrogen piggery wastewater without any pretreatment. In the model, the AGS utilizes readily biodegradable substrates for simultaneous storage, growth and metabolism during the feast phase. It further utilizes storage products for secondary growth and metabolism during the famine phase. Finally, it produces inert organic carbon through the decay. For nitrogen removal, nitrification process is mainly heterotrophic nitrification. Denitrification is completed by a combined process of anoxic and aerobic denitrification. The comparison between simulation results and experimental data shows that the modified model satisfactorily simulated the organic substrates degradation, nitrification and denitrification processes of treatment of high-concentration piggery wastewater by AGS.

Here, we combined the aquatic cultivation of the energy crop duckweed and nitrogen limitation to quickly produce starch-rich biomass. Under N limitation, duckweed can quickly accumulate starch at up to 52.37 ± 0.57% (dry weight). In the process, nitrogen use efficiency (NUE) reached 61.3 ± 1.8 kg biomass kg−1 N, exceeding that of most cereals. In this paper, we elucidated for the first time the mechanism of the high NUE of duckweed under N limitation. First, duckweed possesses higher N transport ability than most cereals and trees and can efficiently accumulate abundant N in vivo under N-sufficient condition. In addition, under N limitation, the stable expression and activity of key enzymes related to both carbon fixation and N assimilation ensured normal biomass accumulation. Furthermore, the efficient ubiquitin-proteasome system (UPS) and autophagy activated the endogenous N remobilization and recycling. Combined with the sharp increase in the expression and activity of duckweed glutamine synthase (GS), duckweed can efficiently redistribute and reuse the endogenous N to support its growth and starch accumulation. Especially, sewage was used to duckweed pre-cultivation in pilot-scale experiment, the approach can simultaneously achieve starch production and wastewater treatment. In a word, this paper provides an environmentally friendly, cost-effective and promising technology for starch production.

An actively Q-switched all-fiber laser operating at the wavelength of 1920 nm is experimentally demonstrated based on a readily accessible commercial Tm-doped silica fiber. The Q-switching is achieved by polarization modulation through the stress-induced birefringence using a piezoelectric transducer (PZT) as the Q-switcher. The pulsed fiber laser can be operated with the repetition rates ranging from tens of kilohertz to nearly two hundreds kilohertz with milliwatt average output power.

The polyculture of different duckweed species is likely to integrate their advantages in removing pollutants and starch accumulation. Here, pilot-scale comparisons of three duckweed species (

Polycrystalline materials of REVO4 (RE = Y, Lu, Yb) were synthesized by liquid-phase reaction. An Yb-doped Yb:Y0.71Lu0.29VO4 crystal was grown by the Czochralski method. Dislocations and low-angle boundaries were revealed by chemical etching and transmission electron microscopy (TEM). Continuous-wave (cw) laser action was achieved in the range of 1020.7–1029.0 nm by using a high-power diode laser as the pump source. A cw laser output power of 1.09 W with a slope efficiency of 21.6% was demonstrated for this 0.5 at.% Yb-doped Yb:Y0.79Lu0.21VO4 mixed crystal.

A new series of Yb:Y x Lu 1− x VO 4 ( x = 0.93, 0.85, and 0.71) mixed laser crystals were grown by the Czochralski method. Crystal structure analysis showed that Yb:Y x Lu 1− x VO 4 crystals possessed the similar crystal structure to those of the tetragonal YVO 4 and LuVO 4 . The polarized absorption spectra were measured at room temperature. The continuous-wave (CW) laser action of diode-pumped Yb:Y x Lu 1− x VO 4 mixed crystal laser was reported. A maximum output power of 1.19 W with a slope efficiency of 21.2% was demonstrated for the Yb:Y 0.93 Lu 0.07 VO 4 crystal. The laser emission spectra and relationship curves between the output power and absorbed pump power ( P abs ) of Yb:Y x Lu 1− x VO 4 ( x = 0.93 and 0.71) crystals were measured. The laser damage threshold values and the optical quality of Yb:Y x Lu 1− x VO 4 mixed crystal were also studied.

In this paper, we generalize a previously developed model describing the behavior of optical bistability in the operation of a quasi-three-level laser by taking into account a Gaussian transverse distribution for the laser mode and including inhomogeneous line broadening for the laser medium. The results show that apart from some quantitative modifications, the primary characteristics of bistability predicted by the simplified model remain correct; in particular, the fundamental condition for the existence of bistability, f

An efficient compact diode-pumped Yb:YAl3(BO3)4 laser operating at room temperature is demonstrated. Output powers of 14.0 and 8.5 W are generated in continuous-wave and passively Q-switched operation, respectively. Laser pulses of 262.8 μJ in energy and 8.1 ns in duration are obtained, the corresponding peak power amounting to 32.4 kW.

Yb: YVO4 single crystals with low doping concentrations of Yb3+ less than 0.3 at% were grown using the Czochralski method. The polarized absorption spectra were measured at room temperature. Strong anisotropy exists in the absorption spectra, resulting in almost entirely different features for π-polarization and σ-polarization. The laser emission spectrum and relationship curve between the output power and absorbed pump power (Pabs) were measured. The continuous-wave laser action of Yb: YVO4 single crystal in a range of 1020.4–1026.3 nm was realized by using a high-power diode laser as the pump source.

Continuous-wave (CW) and passively Q-switching laser performance of the Yb:CNGG and Yb:CLNGG disordered garnet crystals are compared. CW output powers of 6.3 and 7.5 W are generated from the Yb:CNGG and Yb:CLNGG lasers, with slope efficiencies measured to be 63 and 74 %, respectively. In passively Q-switched operation, the average output power reaches 2.0 and 3.1 W, with slope efficiencies of 56 and 65 %, for the Yb:CNGG and Yb:CLNGG lasers, respectively. Laser pulses of 9.5 ns in duration are generated with the two Yb lasers, with the highest pulse energy and peak power amounting to 166.7 μJ and 17.5 kW for the Yb:CNGG laser, and 133.0 μJ and 14.0 kW for the Yb:CLNGG laser. In respects of efficient laser operation and power scaling, the Yb:CLNGG proves to be advantageous over Yb:CNGG, whereas the Yb:CNGG is superior to Yb:CLNGG in energy storage capacity.

Efficient continuous-wave laser operation is demonstrated at room temperature with a new disordered Yb:CLNGG crystal. A maximum output power of 5.0 W is generated at an absorbed pump power of 7.73 W, leading to an optical-to-optical efficiency of 65%, whereas the slope efficiency is determined to be as high as 83%.

Efficient continuous-wave operation is demonstrated at room temperature with a Yb:YVO4 laser end pumped by a 985-nm diode. An output power of 2.46 W is generated at the highest available absorbed pump power of 6.2 W, with an optical-to-optical and slope efficiency of 40 and 76%, respectively. A theoretical calculation of the laser characteristics agrees closely with the experimental results.

A single-frequency actively Q-switched all-fiber laser at 978 nm was developed using a 2-cm-long commercial ytterbium-doped silica fiber and a pair of silica-fiber-based Bragg gratings. The Q-switching is enabled by the stress-induced polarization modulation in the short linear fiber laser cavity. The laser generates actively Q-switched single-frequency laser pulses with a pulse repetition rate ranging from tens of kilohertz to hundreds of kilohertz. The pulse duration and the average/peak power have been characterized. This is, to the best of our knowledge, the first demonstration of a single-frequency all-fiber Q-switched laser below 1 μm using commercial highly ytterbium-doped silica fiber.

Efficient continuous-wave (CW) laser operation on the 4 F 3/2 → 4 I 9/2 transition of Nd:Y0.53Gd0.47VO4, a mixed vanadate crystal, is demonstrated at room temperature employing a compact plano-concave resonator, generating a polarized output power of 0.39 W at 913.2 nm with 2.85 W of pump power absorbed, the optical-to-optical and slope efficiencies being 14 and 25%, respectively.

We report a high power monolithic nanosecond pulsed fiber laser at 1064nm in MOPA configuration. More than 300W average power was achieved for 475 ns pulses at repetition rate of 100 kHz.

We report on a systematic study of the absorption and emission spectral properties of (Yb(0.1)Y(0.9))(3)(Sc(1.5)Ga(0.5))Ga(3)O(12) (Yb:YSGG) crystals. The broad fluorescence spectral lines indicate great potential of Yb:YSGG for tunable and ultrafast laser applications. Efficient continuous-wave (cw) laser oscillation was also demonstrated at room temperature (RT), generating an output power of 6.11 W with an optical-to-optical efficiency of 64.2%, and a slope efficiency of 80.1% with respect to absorbed pump power. The laser emission spectrum shifts to shorter wavelengths as the transmission of the output coupler varies from 3% to 20%, a result that can be explained based on the effective gain cross-sections of Yb:YSGG.

A compact diode-pumped high-pulse-energy Yb:GdCa(4)O(BO(3))(3) laser passively Q-switched with a Cr(4+):YAG saturable absorber is demonstrated at room temperature. An output power of 1.05 W is generated at a pulse repetition rate of 2.5 kHz when the pump power absorbed is 7.7 W, with a slope efficiency determined to be 40%. The laser pulse generated is 10.0 ns in duration, with pulse energy as high as 420 μJ and peak power amounting to 42 kW.

The passive Q-switching laser performance of Yb:YCa(4)O(BO(3))(3) is studied with crystals cut along the principal optical axes. Using a Cr(4+):YAG saturable absorber with initial transmission of 93.7% and an output coupler of transmission of 40%, efficient Q-switched laser operation is achieved with a X-cut crystal, generating an output power of 2.14 W at a pulse repetition rate of 4.5 kHz. The resulting laser pulse is 9.3 ns in duration, with the energy being as high as 476 μJ and the peak power amounting to 51.2 kW. The results demonstrated in this work reveal the great potential of this crystal in developing high-energy compact pulsed lasers.

Polarized absorption and emission spectra and continuous-wave laser performance of a new Yb0.006:Y0.923Lu0.071VO4 mixed vanadate crystal are studied. For π polarization the maximum absorption and emission cross sections are 5.0 × 10−20 cm2 and 8.6 × 10−20 cm2, respectively. Continuous-wave laser operation is demonstrated at room temperature, displaying typical bistable behavior. A maximum output power of 1.90 W is generated with an optical-to-optical efficiency of 29%, while the slope efficiency is 42%.

We report on the results from a comparative study on the continuous-wave laser performance of Yb:YGG, Yb:LuGG, and Yb:GGG gallium garnets grown by the optical floating zone technique, conducted under identical experimental conditions. 5−7 W of output powers were generated with the three garnet crystals in a compact linear resonator longitudinally pumped by a diode laser emitting at 970−974 nm. The optical-to-optical and slope efficiencies measured for Yb:YGG amounted to 68% and 80%, respectively, which proved to be much higher than the corresponding efficiencies for Yb:LuGG (49% and 60%) or Yb:GGG (52% and 64%).

Output-coupling-dependent complex polarization state varying behavior is demonstrated for a continuous-wave Yb:NaY(WO4)2 disordered crystal laser. The laser oscillation can be purely ?-polarized if the output coupling used is kept lower than 5%; for output couplings that are higher than this level, however, the laser will undergo three successive operational regions with increasing pump power, in which ?-polarized, ?- and ?-polarized, and ?-polarized oscillations will be generated, respectively.

A theoretical modeling analysis is presented to study the optical bistability exhibited in the oscillation of an inhomogeneously broadened quasi-three-level laser. All the major characteristics of optical bistability depend on two normalized parameters, f and xa, which are defined by f = Isat,a/Isat,m and xa = 2αa0pa/δ and are related to measurable properties of the laser medium. In comparison with the case of a homogeneously broadened laser, the essential condition for the occurrence of such bistability, f

We demonstrate, for the first time, passively Q-switched laser operation of Yb:Y(3)Ga(5)O(12) garnet crystal. An output power of 4.53 W at 1031 nm was generated at a pulse repetition rate of 55.6 kHz, with a Cr(4+):YAG crystal acting as saturable absorber whose initial transmission was 97.5%, the corresponding pulse energy, duration and peak power were respectively 81.5 μJ, 28.5 ns and 2.86 kW. Laser pulses at a lower repetition rate of 18.2 kHz were also achieved at 1025 nm while the initial transmission of the Cr(4+):YAG crystal was 85.0%, with an output power measured to be 2.56 W, the resulting pulse energy, duration, and peak power being 140.8 μJ, 5.9 ns, and 23.9 kW, respectively.

Efficient laser operation is demonstrated at room temperature with a new Yb:Lu3Ga5O12 garnet crystal. A continuous-wave output power of 5.36 W is generated at a center oscillation wavelength of 1041 nm, with an optical-to-optical efficiency of 51% and the slope efficiency of 63%. In passively Q-switched operation, the maximum average output power reaches 4.0 W (center wavelength of 1034 nm) at a repetition rate of 71 kHz, with optical-to-optical and slope efficiencies measured to be 40% and 50%, respectively. Laser pulses of 26 ns duration are generated with a pulse energy of 91 μJ and peak power of 3.5 kW.

We report on a significant improvement in cw laser performance of the disordered Yb:CNGG crystal. Very efficient cw laser operation is demonstrated at room temperature with a 3.5 mm thick crystal end pumped by a diode laser, generating an output power of 5.15 W with an optical-to-optical efficiency of 46%, whereas the slope efficiency amounts to 80%.