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Hydrogen (H2) is considered an alternative fuel of the future due to its high energy density and non-polluting nature. H2 energy provides many advantages over fossil fuels in that it is renewable, eco-friendly, and efficient. The global demand for H2 is increasing significantly; however, matching the supply of cost-competitive H2 to meet the current demand is a major technological barrier. H2 can be produced from lignocellulosic biomass and serve as a raw material for the synthesis of many industrially important chemicals. The use of thermophilic bacteria for biological production of H2 appears to be a promising alternative route to the current H2 production technologies. However, the carbon and H2 production metabolisms in most thermophilic bacteria have not yet been completely understood. This paper summarizes the recent research progress made toward understanding the carbon utilization for H2 production and developing gene manipulation techniques to enhance the H2 production capabilities in thermophilic bacteria. It reviews the current status, future directions and opportunities that thermophiles can offer to enable a cost-competitive and environmentally benign H2 production bioprocess.  相似文献   

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Previous researchers have tried to predict social and economic phenomena with indicators of public mood, which were extracted from online data. This method has been proved to be feasible in many areas such as financial markets, economic operations and even national suicide numbers. However, few previous researches have examined the relationship between public mood and consumption choices at society level. The present study paid attention to the “Diaoyu Island” event, and extracted Chinese public mood data toward Japan from Sina MicroBlog (the biggest social media in China), which demonstrated a significant cross-correlation between the public mood variable and sales of Sony cameras on Taobao (the biggest Chinese e-business company). Afterwards, several candidate predictors of sales were examined and finally three significant stepwise regression models were obtained. Results of models estimation showed that significance (F-statistics), R-square and predictive accuracy (MAPE) all improved due to inclusion of public mood variable. These results indicate that public mood is significantly associated with consumption choices and may be of value in sales forecasting for particular products.  相似文献   

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l -Asparaginases hydrolyzing plasma l -asparagine and l -glutamine has attracted tremendous attention in recent years owing to remarkable anticancer properties. This enzyme is efficiently used for acute lymphoblastic leukemia (ALL) and lymphosarcoma and emerged against ALL in children, neoplasia, and some other malignancies. Cancer cells reduce the expression of l -asparaginase leading to their elimination. The l -asparaginase anticancerous application approach has made incredible breakthrough in the field of modern oncology through depletion of plasma l -asparagine to inhibit the cancer cells growth; particularly among children. High level of l -asparaginase enzyme production by Escherichia coli, Erwinia species, Streptomyces, and Bacillus subtilis species is highly desirable as bacterial alternative enzyme sources for anticancer therapy. Thermal or harsh conditions stability of those from the two latter bacterial species is considerable. Some enzymes from marine bacteria have conferred stability in adverse conditions being more advantageous in cancer therapy. Several side effects exerted by l -asparaginases such as hypersensitivity should be hindered or decreased through alternative therapies or use of immune-suppressor drugs. The l -asparaginase from Erwinia species has displayed remarkable traits in children with this regard. Noticeably, Erwinia chrysanthemi l -asparaginase exhibited negligible glutaminase activity representing a promising efficiency mitigating related side effects. Application of software such as RSM would optimize conditions for higher levels of enzyme production. Additionally, genetic recombination of the encoding gene would indisputably help improving enzyme traits. Furthermore, the possibility of anticancer combination therapy using two or more l -asparaginases from various sources is plausible in future studies to achieve better therapeutic outcomes with lower side effects.  相似文献   

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From the soil, plants take up macronutrients (calcium, magnesium, nitrogen, phosphorus, potassium, sulfur) and micronutrients (boron, chloride, cobalt, copper, iron, manganese, molybdenum, nickel, selenium, and zinc). In acidic soils, aluminum can interfere with nutrient uptake. There is a need for improved diagnostic tests for these soil-derived minerals that are inexpensive and sensitive, provide spatial and temporal information in plants and soil, and report bioavailable nutrient pools. A transgenic whole-cell biosensor detects a stimulus inside or outside a cell and causes a change in expression of a visible reporter such as green fluorescent protein, and thus can convert an invisible plant nutrient into a visible signal. Common transgenic whole-cell biosensors consist of promoter-reporter fusions, auxotrophs for target analytes that are transformed with constitutively expressed reporters, riboswitches and reporters based on Forster Resonance Energy Transfer (FRET). Here, we review transgenic plant biosensors that have been used to detect macronutrients and micronutrients. As plant-based biosensors are limited by the requirement to introduce and optimize a transgene in every genotype of interest, we also review microbial biosensor cells that have been used to measure plant or soil nutrients by co-inoculation with their respective extracts. Additionally, we review published transgenic whole-cell biosensors from other disciplines that have the potential to measure plant nutrients, with the goal of stimulating the development of these diagnostic technologies. We discuss current limitations and future improvements needed, and the long-term potential of transgenic whole-cell biosensors to inform plant physiology, improve soil nutrient management, and assist in breeding crops with improved nutrient use efficiency.  相似文献   

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More than half of human proteins are glycosylated by a bewildering array of complex and heterogeneous N- and O-linked glycans. They function in myriad biological processes, including cell adhesion and signalling and influence the physical characteristics, stability, function, activity and immunogenicity of soluble glycoproteins. A single protein may be glycosylated differently to yield heterogenous glycoforms. Glycosylation analysis is of increasing interest in biomedical and biological research, the pharmaceutical and healthcare industry and biotechnology. This is because it is increasingly apparent that glycosylation changes in diseases, such as cancer, making it a promising target for development of clinically useful biomarkers and therapeutics. Furthermore, as the non-human cells employed in expression systems glycosylate their proteins very differently to human cells, and as glycosylation changes unpredictably under changing environmental conditions, glycans analysis for quality control, optimum efficacy and safety of recombinant glycoproteins destined for human therapeutic use is paramount. The complexities of carbohydrate chemistry make analysis challenging and while there are a variety of robust methodologies available for glycan analysis, there is currently a pressing need for the development of new, streamlined, high throughput approaches accessible to non-specialist laboratories.  相似文献   

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Venomous snakebite is considered the single most important cause of human injury from venomous animals worldwide. Coagulopathy is one of the commonest important systemic clinical syndromes and can be complicated by serious and life-threatening haemorrhage. Venom-induced consumption coagulopathy (VICC) is the commonest coagulopathy resulting from snakebite and occurs in envenoming by Viperid snakes, certain elapids, including Australian elapids, and a few Colubrid (rear fang) snakes. Procoagulant toxins activate the clotting pathway, causing a broad range of factor deficiencies depending on the particular procoagulant toxin in the snake venom. Diagnosis and monitoring of coagulopathy is problematic, particularly in resource-poor countries where further research is required to develop more reliable, cheap clotting tests. MEDLINE and EMBASE up to September 2013 were searched to identify clinical studies of snake envenoming with VICC. The UniPort database was searched for coagulant snake toxins. Despite preclinical studies demonstrating antivenom binding toxins (efficacy), there was less evidence to support clinical effectiveness of antivenom for VICC. There were no placebo-controlled trials of antivenom for VICC. There were 25 randomised comparative trials of antivenom for VICC, which compared two different antivenoms (ten studies), three different antivenoms (four), two or three different doses or repeat doses of antivenom (five), heparin treatment and antivenom (five), and intravenous immunoglobulin treatment and antivenom (one). There were 13 studies that compared two groups in which there was no randomisation, including studies with historical controls. There have been numerous observational studies of antivenom in VICC but with no comparison group. Most of the controlled trials were small, did not use the same method for assessing coagulopathy, varied the dose of antivenom, and did not provide complete details of the study design (primary outcomes, randomisation, and allocation concealment). Non-randomised trials including comparison groups without antivenom showed that antivenom was effective for some snakes (e.g., Echis), but not others (e.g., Australasian elapids). Antivenom is the major treatment for VICC, but there is currently little high-quality evidence to support effectiveness. Antivenom is not risk free, and adverse reactions can be quite common and potentially severe. Studies of heparin did not demonstrate it improved outcomes in VICC. Fresh frozen plasma appeared to speed the recovery of coagulopathy and should be considered in bleeding patients.  相似文献   

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A device for simultaneously measuring the relative fitness of multiple bacterial populations was developed and evaluated. The new device eliminates the need to construct strains with selectively neutral markers so that strains can be readily distinguished, and it provides a means to perform multispecies competition experiments.  相似文献   

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