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651.
A bimorph transducer was proposed to improve the detection sensitivity and imaging depth of photoacoustic and ultrasound (PAUS) dermoscope. By applying the bimorph transducer, the imaging depth and sensitivity of PAUS dermoscope were enhanced by simultaneously improving excitation efficiency and reception bandwidth. The integrated design of the imaging head of the dermoscope makes it highly convenient for detecting human skin. The PAUS imaging performance was demonstrated via visualizing subcutaneous tumor and depicting full structures of different skin layers from epidermis to subcutaneous tissue. The results confirm that the dermoscope with the bimorph transducer is well suited for PA and US dual‐modality imaging, which can provide multi‐information for skin disease. 相似文献
652.
van Luijk CM Bruinsma M van der Wees J Lie JT Ham L Melles GR 《Cell and tissue banking》2012,13(2):333-339
The aim of this study was to report the efficacy of adding chlorhexidine to the protocol for decontamination of human donor globes prior to excision of corneo-scleral rims for future keratoplasty procedures. In 2005, chlorhexidine was introduced by our eye bank as an additional step in the protocol for decontaminating human donor globes. After 5?years, we prospectively evaluated the number of contaminations. Out of 2,891 globes included in our study, 2,663 globes were processed, of which 36 (1.4%) were considered contaminated. Seventeen contaminations (0.6%) were detected by culturing limbal swabs, directly after decontamination, eight (0.3%) by visible discoloration of the culture medium carrying a corneo-scleral rim, and eleven (0.4%) after inoculation of the culture medium on blood agar plates. Importantly, after 4?weeks of incubation, none of the aerobic and anaerobic cultures taken from the secondary ??transport medium?? (dextran containing medium used to transport corneal tissue to the transplantation centre) showed microbiological growth. In conclusion, the combined use of 0.02% chlorhexidine and 0.5% povidone-iodine may allow decontamination of donor globes to a level at which the risk of tissue contamination at the time of transplantation is minimized, while corneal viability is preserved. 相似文献
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Zhenzhou Cheng Nan Zhang Le Chang Pengfei Qi Lin Zhang Lie Lin Yan Wang Weiwei Liu 《Journal of biophotonics》2023,16(2):e202200160
Myopia and keratoconus have become common corneal diseases that threaten the quality of human vision, and keratoconus is one of the most common indications for corneal transplantation worldwide. Collagen crosslinking (CXL) using riboflavin and ultraviolet A (UVA) light is an effective approach for treating ophthalmic disorders and has been shown clinically not only to arrest further progression of keratoconus but also to improve refractive power for cornea. However, CXL surgery irradiated by UVA has various potential risks such as surface damage and endothelial cell damage. Here, near-infrared femtosecond laser-based two-photon CXL was first applied to ex vivo human corneal stroma, operating at low photon energy with high precision and stability. After two-photon CXL, the corneal stiffness can be enhanced by 300% without significantly reducing corneal transparency. These findings illustrate the optimized direction that depositing high pulses energy in corneal focal volume (not exceeding damage threshold), and pave the way to 3D CXL of in vivo human cornea with higher safety, precision, and efficacy. 相似文献
655.
Andrade Edilene Pereira de Araújo Nunes Ana Bárbara de Freitas Alves Kilvia Ugaya Cássia Maria Lie da Costa Alencar Mateus de Lima Santos Tayane da Silva Barros Viviane Pastor Amandine Valérie de Figueirêdo Maria Cléa Brito 《The International Journal of Life Cycle Assessment》2020,25(12):2342-2358
The International Journal of Life Cycle Assessment - This paper presents the regionalized water scarcity characterization factors (CFs) of the available water remaining (AWARE) model, which was... 相似文献
656.
Methyl 2,5-disubstituted C18 furanoid fatty ester (viz. methyl 9,12-epoxyoctadeca-9,11-dienoate) was readily converted to methyl 9,12-dioxostearate using mineral or maleic acid. Conversion of the naturally occurring 2,3,5-trisubstituted furanoid fatty ester (viz. methyl 10,13-epoxy-11-methyloctadeca-10,12-dienoate) to the corresponding methyl 10,13-dioxo-11-methylstearate was much slower in rate under similar reaction conditions. The case of separating the dioxo derivatives from a mixture of other common fatty esters was demonstrated and the cyclodehydration of the isolated dioxo derivatives to the parent furanoid ester was rapidly achieved using dilute BF3-methanol complex. 相似文献
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659.
Xueyun Wu Dong Yang Xiangcheng Zhu Zhiyang Feng Zhengbin Lv Yaozhou Zhang Ben Shen Zhinan Xu 《Biotechnology and Bioprocess Engineering》2010,15(4):664-669
The heterologous production of iso-migrastatin (iso-MGS) was successfully demonstrated in an engineered S. lividans SB11002 strain, which was derived from S. lividans K4-114, following introduction of pBS11001, which harbored the entire mgs biosynthetic gene cluster. However, under similar fermentation conditions, the iso-MGS titer in the engineered strain was
significantly lower than that in the native producer — Streptomyces platensis NRRL 18993. To circumvent the problem of low iso-MGS titers and to expand the utility of this heterologous system for iso-MGS
biosynthesis and engineering, systematic optimization of the fermentation medium was carried out. The effects of major components
in the cultivation medium, including carbon, organic and inorganic nitrogen sources, were investigated using a single factor
optimization method. As a result, sucrose and yeast extract were determined to be the best carbon and organic nitrogen sources,
resulting in optimized iso-MGS production. Conversely, all other inorganic nitrogen sources evaluated produced various levels
of inhibition of iso-MGS production. The final optimized R2YE production medium produced iso-MGS with a titer of 86.5 mg/L,
about 3.6-fold higher than that in the original R2YE medium, and 1.5 fold higher than that found within the native S. platensis NRRL 18993 producer. 相似文献
660.
Shu-Yi-Dan Zhou Zhiyang Lie Xujun Liu Yong-Guan Zhu Josep Peñuelas Roy Neilson Xiaoxuan Su Zhanfeng Liu Guowei Chu Ze Meng Junhua Yan Juxiu Liu 《Global Change Biology》2023,29(6):1501-1513
Climate change globally affects soil microbial community assembly across ecosystems. However, little is known about the impact of warming on the structure of soil microbial communities or underlying mechanisms that shape microbial community composition in subtropical forest ecosystems. To address this gap, we utilized natural variation in temperature via an altitudinal gradient to simulate ecosystem warming. After 6 years, microbial co-occurrence network complexity increased with warming, and changes in their taxonomic composition were asynchronous, likely due to contrasting community assembly processes. We found that while stochastic processes were drivers of bacterial community composition, warming led to a shift from stochastic to deterministic drivers in dry season. Structural equation modelling highlighted that soil temperature and water content positively influenced soil microbial communities during dry season and negatively during wet season. These results facilitate our understanding of the response of soil microbial communities to climate warming and may improve predictions of ecosystem function of soil microbes in subtropical forests. 相似文献