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101.
《Water research》1999,33(4):919-928
The decolourisation of cotton bleaching effluent by a wood rotting fungus was studied. It was found that fungus No. 7 could remove more than 70% of the colour (initial A400=2.0–2.4) from the effluent within 4 days under agitated conditions. The fungal mycelia could be reused for a prolonged time and the decolourisation activity of mycelial pellets was quite stable during a long period of cool storage. Many factors affecting the decolourisation process were studied, including: concentration of glucose, effluent, NH4+ and Mn(II); initial pH; temperature. The activity of manganese peroxidase (MnP) appeared to correlate well with the decolourisation rate. After the fungal treatment, an improvement in the treatability of the effluent by other microorganisms was observed. 相似文献
102.
103.
《International Journal of Hydrogen Energy》2020,45(8):5565-5576
Fuel cell electric vehicles and hydrogen refuelling infrastructure are developing quickly in Europe, the USA and Asia. Hydrogen quality for transport applications requires compliance with ISO 14687-2: 2012 and EN 17124:2018 - this needs representative sampling, at the hydrogen production process and at hydrogen dispenser nozzle (which typically fill vehicles to a Nominal Working Pressure of either 35 or 70 MPa). The low thresholds in ISO 14687-2 for oxygen and water can be exceeded if the sampling procedure fails to purge the system sufficiently, which would lead to false results (60% in this study). Purging requirements to remove water were studied using a low pressure sampling rig. For hydrogen dispenser sampling using the Linde H2 Qualitizer (suitable for dispensing pressures up to 70 MPa), purging number and the effect of the initial fill level of a vehicle compressed hydrogen storage system were investigated experimentally to avoid hydrogen quality violation due to oxygen false positive. The study procedure reduces from 60% to 0% hydrogen quality violation. The next challenges highlighted are safe purging and reliable sampling of reactive contaminants in gas cylinders. 相似文献
104.
Orsolya Kinga Gondor Judit Tajti Kamirn ron Hamow Imre Majlth Gabriella Szalai Tibor Janda Magda Pl 《International journal of molecular sciences》2021,22(21)
Although the relationship between polyamines and photosynthesis has been investigated at several levels, the main aim of this experiment was to test light-intensity-dependent influence of polyamine metabolism with or without exogenous polyamines. First, the effect of the duration of the daily illumination, then the effects of different light intensities (50, 250, and 500 μmol m–2 s–1) on the polyamine metabolism at metabolite and gene expression levels were investigated. In the second experiment, polyamine treatments, namely putrescine, spermidine and spermine, were also applied. The different light quantities induced different changes in the polyamine metabolism. In the leaves, light distinctly induced the putrescine level and reduced the 1,3-diaminopropane content. Leaves and roots responded differently to the polyamine treatments. Polyamines improved photosynthesis under lower light conditions. Exogenous polyamine treatments influenced the polyamine metabolism differently under individual light regimes. The fine-tuning of the synthesis, back-conversion and terminal catabolism could be responsible for the observed different polyamine metabolism-modulating strategies, leading to successful adaptation to different light conditions. 相似文献
105.
《Acta Metallurgica Materialia》1991,39(3):317-322
The microstructural features developed after rolling of aluminum alloys have thoroughly been described in the past by means of transmission electron microscopy. However, with the exclusive use of this technique, it is not possible to ascertain the dislocation distribution and hence the associated modeling of the hardening behavior. In this paper, we show that the simultaneous use of several experimental techniques such as elastic limit, X-ray line broadening and density measurements leads to coherent results pertaining to the dislocations substructures of Al and AlMg solid solution alloys. Particularly, with the help of dislocation density determination it was found that the hardening follows a classical ϱ1/2 law of the dislocation forest type for most of the strain range. In the cellular regime of pure aluminum, a cell wall hardening mechanism based on an absorption-emission of dislocations holds. A Hall-Petch type law may then be formally followed if a cell wall multiplication with constant dislocation density occurs during rolling. 相似文献
106.
lvaro Petersen-Uribe Marcel Kremser Anne-Katrin Rohlfing Tatsiana Castor Kyra Kolb Valerie Dicenta Frederic Emschermann Bo Li Oliver Borst Dominik Rath Karin Anne Lydia Müller Meinrad Paul Gawaz 《International journal of molecular sciences》2021,22(20)
Platelets play a significant role in atherothrombosis. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is critically involved in the regulation of LDL metabolism and interacts with platelet function. The effect of PCSK9 in platelet function is poorly understood. The authors of this article sought to characterize platelets as a major source of PCSK9 and PCSK9’s role in atherothrombosis. In a large cohort of patients with coronary artery disease (CAD), platelet count, platelet reactivity, and platelet-derived PCSK9 release were analyzed. The role of platelet PCSK9 on platelet and monocyte function was investigated in vitro. Platelet count and hyper-reactivity correlated with plasma LDL in CAD. The circulating platelets express on their surface and release substantial amounts of PCSK9. Release of PCSK9 augmented platelet-dependent thrombosis, monocyte migration, and differentiation into macrophages/foam cells. Platelets and PCSK9 accumulated in tissue derived from atherosclerotic carotid arteries in areas of macrophages. PCSK9 inhibition reduced platelet activation and platelet-dependent thrombo-inflammation. The authors identified platelets as a source of PCSK9 in CAD, which may have an impact on LDL metabolism. Furthermore, platelet-derived PCSK9 contributes to atherothrombosis, and inhibition of PCSK9 attenuates thrombo-inflammation, which may contribute to the reported beneficial clinical effects. 相似文献
107.
《International Journal of Hydrogen Energy》2020,45(60):34695-34706
Substrate and product inhibitions have a significant effect on dark fermentative hydrogen gas production. Particularly, rapid formation of volatile fatty acids leads to fast pH decreases shifting the metabolic pathway. Therefore, controlling volatile fatty acid accumulation has great importance in maintaining effective hydrogen production. In this context, a dilution strategy was applied to regulate volatile fatty acids levels within the desired concentration range. A three-factor Box-Behnken statistical experiment design was established to assess the effects of dilution time, dilution percentage and initial COD concentration on hydrogen formation yield and rate. Highest hydrogen yield (7.7 mL H2/mLreactor) and rate (21. 47 mL H2/h or 9.38 mmol/Lreactor.h) were achieved when 85 gCOD/L containing fermentation media was diluted with a percentage of 130 of the initial working volume at the 3rd hour of the fermentation period. Moreover, this strategy enabled to start fermentation with 55 g glucose/L. 相似文献
108.
Francesca Marini Francesca Giusti Teresa Iantomasi Maria Luisa Brandi 《International journal of molecular sciences》2021,22(20)
Parathyroid tumors are rare endocrine neoplasms affecting 0.1–0.3% of the general population, including benign parathyroid adenomas (PAs; about 98% of cases), intermediate atypical parathyroid adenomas (aPAs; 1.2–1.3% of cases) and malignant metastatic parathyroid carcinomas (PCs; less than 1% of cases). These tumors are characterized by a variable spectrum of clinical phenotypes and an elevated cellular, histological and molecular heterogeneity that make it difficult to pre-operatively distinguish PAs, aPAs and PCs. Thorough knowledge of genetic, epigenetic, and molecular signatures, which characterize different parathyroid tumor subtypes and drive different tumorigeneses, is a key step to identify potential diagnostic biomarkers able to distinguish among different parathyroid neoplastic types, as well as provide novel therapeutic targets and strategies for these rare neoplasms, which are still a clinical and therapeutic challenge. Here, we review the current knowledge on gene mutations and epigenetic changes that have been associated with the development of different clinical types of parathyroid tumors, both in familial and sporadic forms of these endocrine neoplasms. 相似文献
109.
110.
Dmitry L. Maslov Nadezhda V. Zemskaya Oxana P. Trifonova Steven Lichtenberg Elena E. Balashova Andrey V. Lisitsa Alexey A. Moskalev Petr G. Lokhov 《International journal of molecular sciences》2021,22(23)
The increase in life expectancy, leading to a rise in the proportion of older people, is accompanied by a prevalence of age-related disorders among the world population, the fight against which today is one of the leading biomedical challenges. Exploring the biological insights concerning the lifespan is one of the ways to provide a background for designing an effective treatment for the increase in healthy years of life. Untargeted direct injection mass spectrometry-based metabolite profiling of 12 species of Drosophila with significant variations in natural lifespans was conducted in this research. A cross-comparison study of metabolomic profiles revealed lifespan signatures of flies. These signatures indicate that lifespan extension is associated with the upregulation of amino acids, phospholipids, and carbohydrate metabolism. Such information provides a metabolome-level view on longevity and may provide a molecular measure of organism age in age-related studies. 相似文献