Reversible removal of SO2 at low temperature by Bacillus licheniformis immobilized on γ-Al2O3

Bacillus licheniformis R08 biomass was immobilized on γ-Al₂O₃ and the effects of R08 biomass loading, SO₂ concentration, water vapor, oxygen and temperature on removal of SO₂ were investigated. The experimental results indicated that SO₂ saturation capacity increased with increasing R08 biomass loading and SO₂ concentration, but decreased with increasing adsorption temperature. Water vapor activated the adsorbent and promoted SO₂ removal. An increase in oxygen concentration from 5 to 10% had little effect on SO₂ removal. FTIR analysis revealed that the R08 biomass bound to γ-Al₂O₃ mainly by forming R-CO-O-Al bonds. X-ray photoelectron spectroscopy analysis indicated that γ-Al₂O₃ reacted with SO₂ and formed aluminum sulfate in the presence of oxygen when R08 biomass loading was 13.8%, but that amido groups of the R08 biomass reacted with SO₂ and formed sulfite when biomass loading was 32.4%. Ten continuous adsorption-desorption cycles showed that the adsorbent had an excellent regeneration performance.     

A comparative test of phylogenetic diversity indices

Traditional measures of biodiversity, such as species richness, usually treat species as being equal. As this is obviously not the case, measuring diversity in terms of features accumulated over evolutionary history provides additional value to theoretical and applied ecology. Several phylogenetic diversity indices exist, but their behaviour has not yet been tested in a comparative framework. We provide a test of ten commonly used phylogenetic diversity indices based on 40 simulated phylogenies of varying topology. We restrict our analysis to a topological fully resolved tree without information on branch lengths and species lists with presence-absence data. A total of 38,000 artificial communities varying in species richness covering 5-95% of the phylogenies were created by random resampling. The indices were evaluated based on their ability to meet a priori defined requirements. No index meets all requirements, but three indices turned out to be more suitable than others under particular conditions. Average taxonomic distinctness (AvTD) and intensive quadratic entropy (J) are calculated by averaging and are, therefore, unbiased by species richness while reflecting phylogeny per se well. However, averaging leads to the violation of set monotonicity, which requires that species extinction cannot increase the index. Total taxonomic distinctness (TTD) sums up distinctiveness values for particular species across the community. It is therefore strongly linked to species richness and reflects phylogeny per se weakly but satisfies set monotonicity. We suggest that AvTD and J are best applied to studies that compare spatially or temporally rather independent communities that potentially vary strongly in their phylogenetic composition-i.e. where set monotonicity is a more negligible issue, but independence of species richness is desired. In contrast, we suggest that TTD be used in studies that compare rather interdependent communities where changes occur more gradually by species extinction or introduction. Calculating AvTD or TTD, depending on the research question, in addition to species richness is strongly recommended.     

Pollination biology of Albizia lebbeck (L.) Benth. (Fabaceae: Mimosoideae) with reference to insect floral visitors

Indian siris, Albizia lebbeck (L.) Benth. (Fabaceae: Mimosoideae) has significant importance to human beings for its multipurpose use. Insects play a crucial role in the pollination biology of flowering plants. In the current study, we studied the pollination biology of A. lebbeck with special reference to insect floral visitors. The effectiveness of floral visitors was investigated in term of visitation frequency, visitation rate and pollen load during 2012 and 2013. In the second experiment, effect of pollinators on yield of A. lebbeck was studied in open and cage pollination experiments. Floral visitor fauna of A. lebbeck included eight-bees, two wasps, two flies, and two butterflies species. Among them, Apis dorsata, Apis florea, Amegilla cingulata, and Nomia oxybeloides had maximum abundance ranging from 349–492, 339–428, 291–342 and 235–255 numbers of individuals, respectively during two flowering seasons. A. dorsata had the highest visitation frequency (6.44 ± 0.49–8.78 ± 0.48 visits/flower/5min) followed by Amegilla cingulata (6.03 ± 0.43–7.99 ± 0.33 visits/flower/5min) and A. florea (3.61 ± 0.31–4.44 ± 0.18 visits/flower/5min). A. dorsata, N. oxybeloides, and Amegilla cingulata had the highest visitation rates (18.904 ± 1.53–11.43 ± 1.17 flower visited/min) and pollen load (15333 ± 336.22–19243 ± 648.45 pollen grains). The open pollinated flowers had significantly higher capsule weight (4.97 ± 0.21 g), seed weight (1.04 ± 0.05 g), seed numbers per pod (9.80 ± 0.34) and seed germination percentage (84.0 ± 1.78%) as compared to caged flowers. The results suggested bees especially A. dorsata, N. oxybeloides and Amegilla cingulata could be effective pollinators of A. lebbeck.     

Template synthesis of highly ordered Prussian blue array and its application to the glucose biosensing

In this paper, we propose a strategy to form nanoelectrode arrays by electrochemical deposition of the Prussian blue (PB) through highly ordered porous anodic alumina (PAA) membrane. The structure and morphology of the nanoarrays were characterized by scanning electron microscopy (SEM). As the highly ordered PB arrays can behave as an ensemble of closely spaced but isolated nanoelectrodes, the nanostructured PB arrays are successfully applied to improve the analytical performances of glucose by electrocatalytic reduction enzymatically liberated H₂O₂. The resulting PB based nanoelectrode arrays show a wide linear calibration range over three orders of magnitude of glucose concentrations (5.0 × 10⁻⁶ to 8.0 × 10⁻³ M) and a low detection limit of 1 μM. Moreover, the biosensor exhibits other good characteristics, such as short response time, high selectivity, excellent operation stability. In addition, effects of the glucose oxidase (GOx) loading, applied potential and pH on the biosensor performance were also discussed.     

Depth distribution of adults and immatures of twoTribolium Castaneum strains in pure and mixed cultures

1. The distribution of adults and immatures of two Tribolium castaneum strains in plexiglas towers was studied both in single-strain and in mixed cultures.
2. The adults of the + + strain tended to be, on the average, deeper in the flour than the bb adults, in pure and in mixed cultures.
3. Adult distribution was independent of sex.
4. The correlation between adult and egg distribution was usually negative, due to either adult movement in the flour, or to reduced fecundity and increased cannibalism of eggs where adults were numerous, or both.
5. Larvae, and especially pupae, of bb were more abundant in the upper sections, and + + in the lower sections, of towers, both in pure and in mixed cultures and, in particular, at the higher density.
6. In general, the distribution of the strains in the mixed cultures was very similar to the pure cultures, showing a very small effect of the interaction between the two strains, in comparison with GHENT’S results with two species. It seems that the two strains are very much alike in their ability to exploit their environment and therefore their success is the same (when pupal cannibalism is reduced) whether the biological component of the environment is composed of one or two strains.

     

杉木火力楠混交林养分归还与生产力

通过对野外试验和室内测试数据的整理分析．比较研究了杉木火力楠混交林和 杉木纯林养分归还、吸收等生态过程的特征以及生产力结果表明混交促进了养分归还过 程．可提高土壤肥力和系统生产力．１５年生混交林技和叶凋落物分别是纯林的２倍和３ 倍,其中容易分解的火力楠凋落物占 ６４％．混交林通过凋落物分解所归还的养分是纯林 的 ２～ ３倍．相当年凋落量 ６５． ９％的混交林根系年死亡量是纯林的 ２倍,在整个系统养分 归还中占有很大的份额．混交林土壤全 Ｎ、 ＮＨ＋４－Ｎ和有效 Ｋ分别比纯林提高 ６４． ３％。 ８２． ３ ％和 ６３． １％．与此同时土壤孔隙组成和水分过程也大为改善．混交林生产力较纯林 提高５２．７％．混交林５种大量元素的归还／吸收比率是纯林的２倍,表明混交林养分循环 效率较高,较少的人为维持可以保持较高的生产力水平．     

Pectolytic enzymes co-immobilization on γ-alumina spheres via organophosphate compounds

Endopectinlyase (EC 4.2.2.10), endopolygalacturonase (EC 3.2.1.15) and pectinesterase (EC 3.1.1.11) present in a commercial mixture were co-immobilized on γ-alumina spheres activated with organophosphate compounds. Staining of the alumina-enzyme complexes with a dye specific for protein showed that only the carrier external surface was available for protein binding. When confined in a packed bed reactor, the activity of the co-immobilized enzymes brought about a viscosity decrease of 70–90% in pectin and polygalacturonic acid solutions, respectively. Sixty per cent of the initial activity was retained from the immobilized enzymes after the sixth utilization cycle on both the substrates used. The immobilized enzymes were also active against fresh apple juice producing a 90% reduction in viscosity in the first five cycles of utilization.     

在细胞含质体数目不均、分裂不同步条件下突变质体随细胞分裂而传递的模式

本文在细胞质体数目不均等、分裂不同步条件下建立了突变质体随细胞分裂而传递的数学表达式,并在具体给定条件下给出了具体计算原始细胞分裂n次后其子细胞含有x个质体,且其中已有j个质体发生突变的可能性（即概率）的公式。     

High-Affinity Receptor Sites and Rapid Proteolytic Inactivation of Neurotensin in Primary Cultured Neurons

The present article describes the interaction of neurotensin with specific receptors in pure primary cultured neurons and the mechanisms by which this peptide is inactivated by these cells. Neurotensin binding sites are not detectable in nondifferentiated neurons and appear during maturation. The binding at 37 degrees C of [monoiodo-Tyr3]neurotensin to monolayers of neurons 96 h after plating is saturable and characterized by a dissociation constant of 300 pM and a maximal binding capacity of 178 fmol/mg of protein. The binding parameters as well as the specificity of these receptors toward neurotensin analogues reveal close similarities between the binding sites present in primary cultured neurons and those described in other membrane preparations or cells. Neurotensin is rapidly degraded by primary cultured neurons. The sites of primary inactivating cleavages are the Pro7-Arg8, Arg8-Arg9, and Pro10-Tyr11 bonds. Proline endopeptidase is totally responsible for the cleavage at the Pro7-Arg8 bond and contributes to the hydrolysis mainly at the Pro10-Tyr11 site. However, the latter breakdown is also generated by a neurotensin-degrading neutral metallopeptidase. The cleavage at the Arg8-Arg9 bond is due to a peptidase that can be specifically inhibited by N-[1(R,S)-carboxy-2-phenylethyl]-alanyl-alanyl-phenylalanyl-p- aminobenzoate. The secondary processing occurring on neurotensin degradation products are: a bestatin-sensitive aminopeptidasic conversion of neurotensin11-13 to free Tyr11, and a rapid cleavage of neurotensin8-13 by proline endopeptidase. A model for the inactivation of neurotensin in primary cultured neurons is proposed and compared to that previously described for purified rat brain synaptic membranes.     

Biocompatibility of alumina-based biomaterials–A review

In today's medicine world, alumina-based biomaterials owing to their excellent biomechanical, and biocompatibility properties play a key role in biomedical engineering. However, the literature still suffers from not having a valid database regarding the protein adsorption and subsequently cell responses to these surfaces. Proteins by adsorption on biomaterials surfaces start interpreting the construction and also arranging the biomaterials surfaces into a biological language. Hence, the main concentration of this review is on the protein adsorption and subsequently cell responses to alumina’s surface, which has a wide range biomedical applications, especially in dentistry and orthopedic applications. In the presented review article, the general principles of foreign body response mechanisms, and also the role of adsorbed proteins as key players in starting interactions between cells and alumina-based biomaterials will be discussed in detail. In addition, the essential physicochemical, and mechanical properties of alumina surfaces which significantly impact on proteins and cells responses as well as the recent studies that have focused on the biocompatibility of alumina will be given. An in depth understanding of how the immune system interacts with the surface of alumina could prove the pivotal importance of the biocompatibility of alumina on its success in tissue engineering after implantation in body.