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Precipitation has been studied as an alternative downstream processing step of biopharmaceuticals to replace chromatography. In protein precipitation, previous studies showed precipitation efficiency and product qualities were influenced by the precipitation agents (e.g., salts, organic solvents, polymers). For bioactive peptides, however, the impacts of precipitation agents had rarely been studied. We previously studied salting-out precipitation of glycopeptide vancomycin (Van) used as the model peptide. The present work compared antisolvent (with acetone) and salting-out precipitations in their precipitation efficiency and product qualities. The phase behavior study showed that heavy precipitates composed of nanoparticles were the predominant products of antisolvent precipitation, in contrast to crystalline microparticles produced by salting-out. At their respective optimal conditions (e.g., pH, Van concentration), batch antisolvent precipitation had significantly higher yield than salting-out. Other than faster dissolution of antisolvent precipitates attributed to their smaller size, both precipitates exhibited comparable purity, peptide secondary structures, thermal stability, and antimicrobial activity. Ministry of Education (MOE) The authors would like to acknowledge the research funding from Ministry of Education Singapore (Grant No. AcRF RG82/20).

The present work evaluated for the first time the use of continuous slug flow crystallizer (CSFC) in bulk seeded protein crystallization, using lysozyme (LYZ) as the model protein. LYZ crystals pre-prepared in batch crystallizer were used as seeds. The crystallization was performed at supersaturation level below the metastable-zone-limit. The resultant crystal size distribution (CSD), CSD's reproducibility, LYZ's bioactivity, and crystallization efficiency as characterized by the space-time-yield (STY, mg/h·L) were determined. The results showed that the CSFC's performance was governed by the flowrate, where a trade-off existed between crystal quality and crystallization efficiency upon varying the flowrate. At low flowrates, which reduced the shear rate and prolonged the residence time, well-defined large tetragonal crystals were produced attributed to suppressed secondary nucleation and extended crystal growth, but low STY due to difficulty in transporting the seeds/products crystals. Higher flow rates led to higher STY, but increased production of small non-tetragonal crystals that formed agglomerates. Compared to batch crystallizer, the CSFC produced LYZ crystals of similar average size, morphology, and bioactivity, but with roughly 50% lower STY, as the batch's high-shear environment promoted secondary nucleation, hence higher crystallization rate. The CSD's width and reproducibility was nevertheless significantly improved in CSFC. Ministry of Education (MOE) The authors would like to acknowledge the funding from Ministry of Education Singapore under Academic Research Fund Tier 1RG82/20 (2021).

Continuous crystallization has been proposed as the downstream processing step for the purification of pharmaceutical proteins aimed at alleviating the manufacturing bottleneck caused by the limitations of chromatography-based operations at high upstream production titers. Herein we reviewed the current state of research in continuous protein crystallization from which future research directions were identified. While the benefits of batch-to-continuous manufacturing transformation have been long established, progress in continuous protein crystallization lags behind its small-molecule counterpart. The reasons are because the challenging nature of protein crystallization, even when performed in the batch platform, and the lack of well-understood proteins available for thorough study. Nevertheless, successful batch-to-continuous transformations in both mixed-suspension-mixed-product-removal crystallizer and tubular crystallizers (i.e. slug flow, oscillatory baffled flow) have been demonstrated using lysozyme or monoclonal antibody as the model protein. Compared to the batch platform, the continuous platform produces comparable crystallization yield but with higher production capacity (g/h). Strategies to optimize the crystallizer's performance based on modeling and simulation results are also available. Future research should (1) study a wider range of proteins with impurities incorporated in the raw material streams, and (2) adopt advancements in continuous crystallization of small-molecule pharmaceuticals to improve the crystal quality and yield. Ministry of Education (MOE) The authors would like to thank the Ministry of Education Singapore for funding this work (Grant No. RG7/17 PI: Kunn Hadinoto Ong).

Ideal metal-organic frameworks (MOFs) are those have not only significant adsorption separation performances but also excellent vapor and/or thermal stability. In this work, a calcium-based metal-organic framework with high vapor-stability and thermostability, Ca(squarate), was prepared using readily available precursor (CaCO3) and squaric acid as starting materials by hydrothermal method. Characterization techniques including PXRD, TGA and BET surface area analysis reveal that this MOF remains stable no matter whether it was soaked in water or exposed to air for as long as 2 weeks. Moreover, the studied MOF material is capable of discriminating C2 hydrocarbon molecules as it has an appropriate pore diameter around 3.4 A. Excellent efficient separation for C2H2/C2H4 mixture (50:50, v/v) with an adsorption selectivity of 8.1 was realized at room temperature and ambient pressure, on the other hand, it also displayed a good separation performance for C2H4/C4H6 mixture (50:50, v/v) with an adsorption selectivity of 5.9. Furthermore, adsorption mechanism of C2 hydrocarbons in this framework was investigated by the DFT-D calculation. The results revealed that this framework discriminated light hydrocarbons as a result of different interaction strength between hydrocarbons and framework that mainly arise from π-π interactions.

Mestrado em Desenvolvimento e Cooperação Internacional A China é a origem do chá, e a indústria do chá é uma indústria tradicional com uma longa história na China. A indústria do chá tem importância certa na importação e exportação da China. No entanto, a competitividade e a posição da indústria do chá chinesa no mercado internacional continuam a diminuir devido a fatores subjetivos e objetivos. Quais são as razões para o declínio da indústria do chá da primeira no mundo? Quais são a situação atual e os desafios? Esta dissertação tem como objetivo apresentar a situação atual e as características da indústria do chá chinesa, descobrir os problemas enfrentados pela indústria do chá chinesa e as razões para o declínio da competitividade sob a globalização e estender da utilização abrangente da indústria do chá ao cadeia global de valor por meio de pesquisa bibliográfica e análise qualitativa. Apresenta algumas sugestões para o desenvolvimento futuro da indústria do chá chinesa e o aumento da sua competitividade internacional, o que ajudará a indústria do chá chinesa a se internacionalizar e se juntar à cadeia global de valor. China is the hometown of tea, and tea industry is a traditional industry with a long history of China. It has a certain importance in China's import and export. However, the competitiveness and position of Chinese tea industry in the international market is continuing to decline due to subjective and objective factors.What are the reasons for the declining status of tea industry from the first in the world? What are the current situation and challenges? This paper aims to introduce the current situation and characteristics of Chinese tea industry, find out the problems faced by Chinese tea industry and the reasons for the decline in competitiveness under the background of globalization and extend from the comprehensive utilization of the tea industry to the global value chain by means of literature research and qualitative analysis. It puts forward some suggestions for the future development of Chinese tea industry and the enhancement of its international competitiveness, which will help Chinese tea industry to go international and join the global value chain. info:eu-repo/semantics/publishedVersion

This retrospective study was conducted to examine the development and current status of pediatric liver transplantation (LT) in western China. Clinical, demographic, morbidity, and mortality data were collected to analyze. It included 260 consecutive pediatric LTs performed at three centers in western China between January 2000 and May 2019. Kaplan-Meier graft survival rates at 1, 3, 5, and 10 years were 82.1%, 77.2%, 76.6%, and 76.6%, respectively; corresponding patient survival rates were 84.7%, 80.7%, 80.0%, and 80.0%, respectively. More patients underwent living donor liver transplantation (LDLT; n = 188 (73.4%)) than deceased-donor liver transplantation (DDLT; n = 68 (26.6%)). Survival was better after LDLT (91.5%, 86.6%, and 80.6% at 1, 3, and 5 years, respectively) than after DDLT (80.9%, 72.4%, and 63.9%, respectively; P < .05). Biliary atresia was the leading LT indication (n = 141 (55.1%)), followed by metabolic disease (n = 36 (14.1%)), which was associated with the best recipient survival (88.5% at 5 years). The transplant era and graft-to-recipient body weight ratio (GRWR) also significantly predicted overall survival. Survival rates at 5 years were worst in 2000-2005 (54.5%) and best for GRWRs of 0.8%-4% (80.4%). The development of pediatric LT in western China began slowly, but the quantity and quality of pediatric LT has progressed in recent years. This procedure is now a promising and reliable treatment for children with end-stage liver disease in western China.

Mg-MOF-74 is one of the most well-known metal–organic frameworks (MOFs) and has been widely studied for gas adsorption and separation. Nevertheless, employment of original Mg-MOF-74 in powder form inevitably leads to a high pressure drop across column and even dust pollution in practical application. In this work, we molded powder Mg-MOF-74 into extrudates and tested its performance on adsorptive separation of ethylene/ethane mixture for the first time, taking commercialized benchmark 13X zeolite as comparison. Powder X-ray diffraction (XRD), scanning electron microscopy (SEM), specific surface area measurements, and thermal gravimetric analysis (TGA) were performed to characterize the transformed samples, and adsorption equilibrium of ethylene and ethane on molded Mg-MOF-74 were measured at 273 and 298 K and pressure up to 1 bar. The potential industrial application of molded Mg-MOF-74 was examined through breakthrough and regeneration experiments, revealing that molded Mg-MOF-74 was feasible and stable ...

Fluorescent materials play an extremely important role in understanding the microbiological world. New fluorescent materials which have good photophysical properties, low cytotoxicity, and multi-channel fluorescent imaging capability are still urgently needed, even though many kinds of fluorescent materials have already been synthesized. In this work, a new polythiophene derivative (PT-OH-PPR) modified with a porphyrin group in its side chain was designed and fabricated through FeCl3 oxidative polymerization. The obtained PT-OH-PPR has wide absorption and emission spectral range, good water solubility and low cytotoxicity. Importantly it could be enriched in the cytoplasm of A549 cells and be excited by two excitation wavelengths (488 nm and 559 nm), which provides a promising application in dual-channel cell imaging.

Continuous crystallization of proteins at short residence time and high supersaturation level is attractive in terms of the space-time yield and production efficiency. Nevertheless, it is rarely pursued due to its less-than-desirable crystal size distribution (CSD) characterized by the abundance of small crystals due to high nucleation rate. The small crystals were prone to random agglomeration, resulting in poor crystals’ residence time distribution, hence low CSD's reproducibility. Herein we developed a segmented slug flow crystallizer (SFC) design operated at short residence time (