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In recent years, environmental pollution caused by excessive exploitation and utilization of the Earth’s fossil fuels, extreme exploitation of land resources, and excessive emissions of carbon dioxide (CO2) has caused people to think about how to reduce CO2 emissions and capture the existing CO2 in the atmosphere. The reduction of CO2 emissions can be summarized into two aspects. Firstly, people could use renewable energy to provide energy support for economic and social development. These renewable energies mainly include solar energy; wind energy, hydro, and marine energies; geothermal energy; and biomass energy. The second aspect is the sequestration and conversion of CO2. CO2 is also a form of carbon resource that can be a favorable alternative to traditional carbon resources. The utilization of CO2 can solve both environmental pollution and depletion of traditional carbon resources at the same time. In this paper, the development of five renewable energy sources and their applications in China were discussed, and the methods of effective sequestration and conversion of CO2 were presented. Energy and environment are closely related to the development of modern society. The problems caused by excessive CO2 emissions cannot be ignored and the sequestration of the greenhouse effect requires joint efforts of mankind.
In order to provide a sound basis for the performance evaluation of a local government’s air pollution prevention and abatement measures, the mass concentrations of PM2.5 and PM10 and the concentrations of different sized particles were measured in August 2013. Meanwhile, the influencing factors and sources of atmospheric particulate matters were analyzed by combining meteorological factors and gaseous pollutants. The results indicated that PM2.5 and PM10 in Zhuzhou were (30.3±12.2) μg·m⁻³ and (56.4±26.6) μg·m⁻³, respectively. The mean values of the particle number concentration in the size range of 0.5~1 μm and 1~2.5 μm on sunny days were (121.2±75.9) cm⁻³ and (6.8±3.7) cm⁻³, respectively, whereas in the rainy days they sharply increased to (868.7±262.1) cm⁻³ and (347.9±238.6) cm⁻³, which accounted for 71.0% and 28.4% of the total number of concentrations, respectively. Backward trajectory analysis demonstrated that the air masses in Zhuzhou city mainly came from three directions: southeast (52.2%), southwest (24.7%), and northeast (23.1%). Although accounting for a minor fraction, the northeast air mass had the largest effect on particle concentrations in Zhuzhou and also carried a lot of gaseous primary pollutants.
Many Jurassic fossil nemestrinid flies have been found in the Palaearctic region. China is an important locality for fossil nemestrinid flies. Up to now, 2 genera with 3 species have been discovered in China. In the present paper, a third genus and species, Ahirmoneura neimengguensis Zhang, Yang, and Ren, gen. et sp. nov., from the Middle Jurassic Daohugou Formation of China is described. A key to genera of fossil nemestrinid flies from China is given.
In order to screen differentially expressed genes during caste differentiation induced by pollen, larvae of Apis mellifer ligustica were developed in an incubator under controlled temperature and relative humidity until emergence. Worker bee morphology was induced by addition of water-soluble extracts from pollen in larval diets. After all of the developmental periods, the external characters and developmental degree of ovaries were evaluated to confirm the caste of new adults. Transcripts from larvae of developing queens and workers were profiled by differential-display RT-PCR analysis and differentially expressed fragments were reconfirmed by dot-blot assay. Our results showed that caste differentiation was triggered by the intake of pollen extracts. Six transcript-derived fragments were isolated and three of them are reported for the first time. We conclude that differential display is a feasible approach to identifying differentially expressed genes. The identification of up-regulated caste-differentiation-related genes provided interesting clues about the activation of biochemical steps relevant to this progress.
This study developed the hybrid partial-nitrification and anammox (HPNA) reactor to increase efficiency in ammonia nitrogen (NH₄⁺-N) removal. The HPNA reactor contained a fixed bed filled with biofilm carrier and a fluidized bed with mechanical stirrer to maximize withholding the sludge. The reactor achieved a total nitrogen (TN) removal efficiency of 70% and NH₄⁺-N removal efficiency of 84%. The maximum nitrogen loading rate (NLR) of 6.1 kg-N/m³/d and nitrogen removal rate (NRR) of 4.7 kg-N/m³/d were achieved with a short hydraulic retention time (HRT) of 3 h. After 160 days of operation, both the mixed liquid suspended solids (MLSS) and the mixed liquor volatile suspended solids (MLVSS) increased in the lower part (from 3.7 to 14.7 g/L and 1.8 to 10.9 g/L, respectively) and the upper part (from 3.7 to 11.8 g/L and 1.9 to 6.7 g/L, respectively). The proteins (PN)/ polysaccharides (PS) ratio increased from 0.96 to 1.1 in the lower part but decreased to 0.7 in the upper part. Bacterial community profiles generated from 16S rRNA sequences further showed that the ammonium-oxidizing bacteria (AOB) Nitrosomonas and the anammox bacterium Brocadiales were enriched in the HPNA reactor.
Canine mammary tumors are the most common neoplasms in intact female dogs. The surgery cannot always solve the problem, chemotherapy are recommend to these patients. However, chemotherapy could always fail because of multidrug resistance (MDR). Through stepwise increasing 5-Fluorouracil (5-FU) concentration in the culture medium, a 5-FU-resistant canine mammary tumor cell line CMT7364/5-FU was established to disclose the molecular mechanism of the drug resistance. Cell morphology, cell sensitivity to drugs, growth curves, expression of proteins, and chemo-sensitivity in vivo were compared between the parental cell line and resistant cell line. As compared it to its parental cell line (CMT7364), CMT7364/5-FU showed different morphology, cross-resistant to other chemo-drugs and a prolonged population doubling time (PDT). The drug efflux pump proteins (ABCB1 and ABCG2) in CMT7364/5-FU were up-regulated. In vivo, the similar result revealed that CMT7364/5-FU cell line was more resistant to 5-FU. In conclusion, a 5-FU-resistant canine mammary tumor cell line (CMT7364/5-FU) was successfully established, it can serve as a good model for researching the mechanism of MDR and screening effective agents to reverse drug resistance.
Anthocyanins are natural bioactive pigments in plants that play important roles in many physiological functions. They are found in various tissues and can protect plants against different stress conditions. Anthocyanins are synthesized and accumulate in nutritional organs, which is crucial for plants to adapt to and resist adverse environmental conditions, including high exposure to light, ultraviolet light, low temperatures, drought, pests and disease. Some progress has been made in understanding the adaptability of anthocyanin to the external environment. Begonia semperflorens is an excellent model for studying the function and regulation of anthocyanin synthesis. To investigate the biosynthesis and regulation of anthocyanins, RNA sequencing techniques were employed to investigate anthocyanin biosynthesis induced by low temperature in B. semperflorens leaves. A total of 74,779 unigenes with a mean length of 1249 bp were assembled. Functional annotations were implemented using five protein databases. Differentially expressed genes involved in the process of anthocyanin biosynthesis were identified. This study represents the first report of a broad-scale gene expression study on B. semperflorens.
The β-carbonic anhydrase (β-CA) is regarded as a zinc-containing enzyme involved in photosynthesis. Here, the rice plants of cv. N22 were treated with foliar spray at a Zn²⁺ concentration range from 0–35.0 mM during the tillering stage. The β-CA expression in the treated leaves was quantitatively determined by RT-qPCR and gel-based immunoblotting techniques, and its enzyme activity and relative chlorophyll concentration were measured. Results indicated that exogenous zinc could benefit rice plants at the tillering stage, particularly chloroplast β-CA with a fourfold enhancement in gene expression and a 14.6 % increase in its activity by treating the rice leaves with the 7.0-mM Zn²⁺ concentration, thereby promoting photosynthesis by a 19.4 % increase in relative chlorophyll concentration per unit leaf area. Results also showed that the application of Zn²⁺ at a concentration exceeding 7.0 mM could result in leaf senescence, and in some cases leaf hurts with significant inactivation (decreasing by approximately 70 %) of β-CA enzyme. It could be concluded that the application of 7.0-mM Zn²⁺ benefits rice plants at the tillering stage. The β-CA activity was associated with the catalytic microenvironment, thus providing an indicator for physiological response to exogenous zinc in rice.
Preclinical studies have suggested that increased adult neurogenesis in the hippocampus might have potential therapeutic effects for Alzheimer’s disease and depression; therefore, it is a target for the treatment of some brain diseases. In this technical communication, we propose a cell‑based fluorescence assay to study the neurogenesis of adult hippocampal progenitor cells that can be used for high‑throughput screening of drugs promoting neurogenesis. Three fluorescent dyes (DAPI, Alexa Fluor 488, and Alexa Fluor 594) and a fluorescence spectrophotometry reader were used, which confirmed that the mutual interference of the three fluorescent dyes is very low. We used this cell‑based fluorescence assay to evaluate the effects of three neurotrophic factors, ciliary neurotrophic factor (CNTF), insulin‑like growth factor 1 (IGF‑1), and IGF‑2 on the promotion of neurogenesis in adult hippocampal neural progenitor cells. The fluorescence intensity ratio of the neuronal marker, class III β‑tubulin, to the housekeeping protein, glyceraldehyde 3‑phosphate dehydrogenase, or nuclear staining dye, DAPI, in CNTF‑treated cells was significantly higher than in control cells. The ratios in IGF‑1‑ and IGF‑2‑treated cells were slightly higher under higher cell density conditions. These results are consistent with those in previous reports; therefore, this report proved the efficacy of this method. Taken together, the results showed that this simple, rapid, and economical cell‑based immunofluorescence assay could be a powerful tool for the rapid screening of drugs that promote adult neurogenesis.
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