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This paper demonstrates a laser diode double-ended pumped Yb: YAG rod regenerative amplifier (RA) with an average power of 37 W, which substantially exceeds the performance of previously reported bulk Yb: YAG medium RAs. Compared to other bulk Yb: YAG medium RAs, we have introduced several enhancements in thermal management, such as employing a double-ended pump to reduce the temperature gradient inside the crystal, and the cooling efficiency is significantly enhanced by designed heat sink. As a result, the thermal effect is effectively suppressed. The system attains high average output power and power stability (RMS = 0.56%) at a pulse repetition rate of 400 kHz. In addition, the output beam maintains excellent quality even under varying high pump powers, demonstrating an M 2 consistently below 1.1. [ABSTRACT FROM AUTHOR]

Sleep deprivation causes significant memory impairment in healthy adults. Extensive research has focused on identifying the biological mechanisms underlying memory impairment. Microglia-mediated synaptic elimination plays an indispensable role in sleep deprivation. Here, the potential role of the CD33/TREM2 signaling pathway in modulating memory decline during chronic sleep restriction (CSR) was evaluated. In this study, adult male C57BL/6 mice were sleep-restricted using an automated sleep deprivation apparatus for 20 h per day for 7 days. The Y-maze test revealed that spontaneous alternation was significantly reduced in CSR mice compared with control mice. The percentage of exploratory preference for the novel object in CSR mice was significantly decreased compared with that in control mice. These memory deficits correlated with aberrant microglial activation and increased phagocytic ability. Moreover, in CSR mice, the CD33 protein level in hippocampal tissue was significantly downregulated, but the TREM2 protein level was increased. In BV2 microglial cells, downregulation of CD33 increased TREM2 expression and improved microglial phagocytosis. Then, the sialic ligand monosialo-ganglioside 1 (GM1, 20 mg/kg, i.p.) was administered to mice once a day during CSR. Our results further showed that GM1 activated CD33 and consequently disturbed TREM2-mediated microglial phagocytosis. Finally, GM1 reversed CSR-induced synaptic loss and memory impairment via the CD33/TREM2 signaling pathway in the CA1 region of the hippocampus. This study provides novel evidence that activating CD33 and/or inhibiting TREM2 activity represent potential therapies for sleep loss-induced memory deficits through the modulation of microglial phagocytosis. [ABSTRACT FROM AUTHOR]

The pulse duration of a burst-mode 100 W Nd-doped picosecond amplifier is nonlinearly compressed in a multi-pass cell device. The spectral broadening and pulse compression are investigated theoretically. The spectral bandwidth is broadened from 0.13 to 3.28 nm experimentally, corresponding to a broadening factor of 25.2. The pulse duration is compressed from 14.2 to 0.99 ps, corresponding to a compression factor of 14.3. The compressed pulse duration of four successive pulses are theoretically estimated to be 0.98 ps, 1.47 ps, 1.86 ps, and 3.07 ps, respectively. The laser power after the grating pair compressor is 72 W. Therefore, the total efficiency of our system reaches 72%. The beam quality after the MPC unit is almost preserved with a M2 value of 1.38 × 1.40. [ABSTRACT FROM AUTHOR]

Type 2 diabetic patients have high risk of developing cognitive dysfunction, in which neural structural plasticity has played a pivotal role. Paired immunoglobulin-like receptor B (PirB), a receptor mainly expressed in neurons, acts as a critical inhibitor of neurite outgrowth and neural plasticity. However, the role of PirB in type 2 diabetes-associated cognitive dysfunction remains unknown. In this study, learning and memory impairment was observed in 24-week-old db/db mice by performing Morris water maze task, and the number of synapses along with the length of postsynaptic density by transmission electron microscopy were reduced in the hippocampus of db/db mice. Furthermore, PirB expression in the hippocampus of db/db mice was significantly upregulated using western blotting and immunofluorescence analysis. In cultured hippocampal neurons, high glucose treatment reduced the length of the longest neurite as well as axon initial segment (AIS), whereas silencing PirB expression rescued high glucose-induced neurite outgrowth inhibition, but not AIS. Additionally, cognitive deficits, dendrite morphology defects, and synapse-related proteins loss in db/db mice were alleviated when PirB knockdown was performed by adeno-associated virus injection. In conclusion, PirB is involved in diabetes-associated cognitive dysfunction through modulation of axon outgrowth and dendritic remodeling, providing a potential therapeutic target for diabetes-associated cognitive dysfunction. [ABSTRACT FROM AUTHOR]

The present research investigated the effect of annealing temperature on surface gradient fine microstructure and wear resistance of low-carbon steel. The results depicted that the optimized annealing temperature from 300 °C to 400 °C can facilitate the formation of a stable fine microstructure. The fine grain size is about 0.2 μm on the topmost surface layer, and the percentage of grain boundary with misorientation angle of 1.5° is 26 %. The full width at half maximum values gradually decreases with increasing temperature from room temperature to 600 °C. In addition, the abrasive wear dominates the entire process for samples annealed at 300-400 °C. The wear mechanism gradually switches to adhesive wear and even delamination wear when the annealing temperature is increased to 500-600 °C. [ABSTRACT FROM AUTHOR]

The original article can be found online at https://doi.org/10.1007/s00340-023-08032-9. B Correction to: Applied Physics B (2023) 129:86 b https://doi.org/10.1007/s00340-023-08032-9 The funding information has been incorrectly published in the original publication. [Extracted from the article]

China has been the forerunner of large-scale membrane bioreactor (MBR) application. Since the first large-scale MBR (⩾ 10 000 m·d) was put into operation in 2006, the engineering implementation of MBR in China has attained tremendous development. This paper outlines the commercial application of MBR since 2006 and provides a variety of engineering statistical data, covering the fields of municipal wastewater, industrial wastewater, and polluted surface water treatment. The total treatment capacity of MBRs reached 1 × 10 m·d in 2010, and has currently exceeded 4.5 × 10 m·d with ∼75% of which pertaining to municipal wastewater treatment. The anaerobic/anoxic/aerobic-MBR and its derivative processes have been the most popular in the large-scale municipal application, with the process features and typical ranges of parameters also presented in this paper. For the treatment of various types of industrial wastewater, the configurations of the MBR-based processes are delineated with representative engineering cases. In view of the significance of the cost issue, statistics of capital and operating costs are also provided, including cost structure and energy composition. With continuous stimulation from the environmental stress, political propulsion, and market demand in China, the total treatment capacity is expected to reach 7.5 × 10 m·d by 2015 and a further expansion of the market is foreseeable in the next five years. However, MBR application is facing several challenges, such as the relatively high energy consumption. Judging MBR features and seeking suitable application areas should be of importance for the long-term development of this technology. [ABSTRACT FROM AUTHOR]

The structure-activity relationship of a new series of tetracyclic spirooxindoles led to the discovery of compound 25a, a potent hNa1.7 blocker with improved ADME properties and in vivo efficacy in the CFA-induced inflammatory pain model. [ABSTRACT FROM AUTHOR]

Sleep deprivation (SD) has been associated with several adverse effects, including cognitive deficit. Emerging evidence suggests microglia-associated neuroinflammation is a potential trigger of cognitive deficit after SD. Stimulator of interferon genes (STING) constitutes an important factor in host immune response to pathogenic organisms and is found in multiple cells, including microglia. STING is involved in neuroinflammation during neuronal degeneration, although how STING signaling affects SD-induced neuroinflammation remains unexplored. In the present study, the chronic sleep restriction (CSR) model was applied to examine the effects of STING signaling on cognition. The results revealed that cGAMP, a high-affinity and selective STING agonist, significantly improved cognitive deficit, alleviated neural injury, and relieved neuroinflammation in CSR mice by activating the STING-TBK1-IRF3 pathway. Moreover, triggering receptor expressed on myeloid cells 2 (TREM2) was upregulated in CSR mice treated with cGAMP, and this effect was abolished by STING knockout. TREM2 upregulation induced by cGAMP regulated the microglia from pro-inflammatory state to anti-inflammatory state, thereby relieving neuroinflammation in CSR mice. These findings indicate cGAMP-induced STING signaling activation alleviates SD-associated neuroinflammation and cognitive deficit by upregulating TREM2, providing a novel approach for the treatment of SD-related nerve injury. [ABSTRACT FROM AUTHOR]