A bioelectrochemical study of a suspension of Escherichia coli cells metabolizing glucose and lactose

The metabolism of glucose and lactose in Escherichia coli K-12 cells has been studied using a bioelectrochemical (BEC) approach. The magnitude and the duration of the response of a BEC anode were found to be functions of the composition of nutrient media and the concentration of bacterial cells. The amount of electricity that is generated enzymatically during the metabolism of a particular substrate depends on the activity of the relevant enzymes. This suggests that the BEC approach can be used for evaluating the activity of particular enzyme systems.     

On the limitations of standard statistical modeling in biological systems: A full Bayesian approach for biology

One of the most important scientific challenges today is the quantitative and predictive understanding of biological function. Classical mathematical and computational approaches have been enormously successful in modeling inert matter, but they may be inadequate to address inherent features of biological systems. We address the conceptual and methodological obstacles that lie in the inverse problem in biological systems modeling. We introduce a full Bayesian approach (FBA), a theoretical framework to study biological function, in which probability distributions are conditional on biophysical information that physically resides in the biological system that is studied by the scientist.     

Comparative analysis of the methods used for finding surface energy to investigate protein interaction behavior on chromatographic supports

Hydrophobic interaction chromatography, an important and effective purification strategy, is generally used for the purification of variety of biomolecules. A basic understanding of the protein interaction behavior is required to effectively separate these biomolecules. A colloidal type extended Derjaguin, Landau, Verwey, and Overbeek calculations were utilized to study the interactions behavior of model proteins to commercially available hydrophobic chromatographic materials that is, Toyopearl Phenyl 650C and Toyopearl Butyl 650C. Physicochemical properties of selected model proteins were achieved by contact angle and zeta potential measurements. The contact angle of chromatographic materials used was achieved through sessile drop method on disrupted beads and capillary penetration method (CPM) on intact beads. The surface properties were further used to calculate the interactions of the proteins to chromatographic supports. The calculated secondary energy minimum of the proteins with the chromatographic materials (from the contact angle values determined through both methods can be correlated with the retention volumes from the real chromatography. The secondary energy minimum values are higher for each protein to the chromatographic materials calculated from the inputs derived through sessile drop method compared to CPM. For instance, immunoglobulin G has secondary energy minimum value of 0.17 kT compared to 0.11 kT, obtained through sessile drop method and CPM, respectively. Average relative values of the energy minimum calculated for all proteins are as 1.51 kT and 1.29 kT for Toyopearl Butyl 650C and Toyopearl Phenyl 650C, respectively, as a conversion factor for estimation of secondary energy minimum for both methods.     

案例教学法结合多媒体教学法在超声专业教学中的应用研究

目的:研究案例教学法结合多媒体教学法在超声专业教学中的应用效果。方法:选择2015年3月到2017年3月在我院超声科实习的112名医学院学生进行研究,按照随机数字表法将医学生分成观察组及对照组,各56例,对照组采用传统教学法实施教学,观察组则采用案例教学法以及多媒体教学法实施综合教学,在每学期末,统计并对比两组学生理论成绩和实践成绩,以及两组学生对教学方式的满意度。结果:观察组的理论成绩和实践成绩各项目分值均分别明显高于对照组,差异均有统计学意义(均P0.05)。观察组学生对教学方式的满意度为98.21%,明显高于对照组的87.50%,差异有统计学意义(P0.05)。结论:案例教学法与多媒体教学法的综合应用能够有效提升超声专业学生的理论成绩和实践成绩,还可改善其对教学方式的满意度,效果较好,临床超声教学可考虑将此种教学方式进行广泛推广,从而更有利于培养专业人才。     

The importance of ‘tooglies’ to the ethnography of F.E. Williams,government anthropologist

The theoretical orientation, encapsulated in the semi‐serious concept of ‘tooglies'of F.E. Williams, government anthropologist for the Territory of Papua in the inter‐war period, is considered. His ideas about culture change are contrasted with those of Bronislaw Malinowski, who acted as his mentor at one time. His treatment of the social organisational anomaly of Sogeri Koiari ‘sex affiliation’, often cited as a case of parallel bilineal descent, is compared with Margaret Mead's analysis of the ‘Mundugumor ropes’, which is classed as the opposite, cross‐sex bilineal descent. It is shown that Williams was able to get a clearer insight into this anomalous data than Mead and Fortune, and, on the whole, worked with an understanding of culture and Papuan social organisation that presages the relational approach of today.     

Recent advances in gene‐enhanced bone tissue engineering

The loss of bone tissue represents a critical clinical condition that is frequently faced by surgeons. Substantial progress has been made in the area of bone research, providing insight into the biology of bone under physiological and pathological conditions, as well as tools for the stimulation of bone regeneration. The present review discusses recent advances in the field of gene‐enhanced bone tissue engineering. Gene transfer strategies have emerged as highly effective tissue engineering approaches for supporting the repair of the musculoskeletal system. By contrast to treatment with recombinant proteins, genetically engineered cells can release growth factors at the site of injury over extended periods of time. Of particular interest are the expedited technologies that can be applied during a single surgical procedure in a cost‐effective manner, allowing translation from bench to bedside. Several promising methods based on the intra‐operative genetic manipulation of autologous cells or tissue fragments have been developed in preclinical studies. Moreover, gene therapy for bone regeneration has entered the clinical stage with clinical trials for the repair of alveolar bone. Current trends in gene‐enhanced bone engineering are also discussed with respect to the movement of the field towards expedited, translational approaches. It is possible that gene‐enhanced bone tissue engineering will become a clinical reality within the next few years.     

Use of host plants by Troidini butterflies (Papilionidae, Papilioninae): constraints on host shift

Molecular phylogenetic analyses were conducted to determine relationships and to investigate character evolution for the Troidini/Aristolochia interaction, in an attempt to answer the following questions: (1) what is the present pattern of use of Aristolochia by these butterflies; (2) is the pattern we see today related to the phylogeny of plants or to their chemical composition; (3) can the geographical distribution of Aristolochia explain the host plant use observed today; and (4) how did the interaction between Troidini and Aristolochia evolve? Analyses of character optimization suggest that the current pattern of host plant use of these butterflies does not seem to be constrained by the phylogeny of their food plants, neither by the secondary chemicals in these plants nor by their geographical similarity. The current host plant use in these butterflies seems to be simply opportunistic, with species with a wider geographical range using more species of host plants than those with a more restricted distribution. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society, 2007, 90 , 247–261.