草履虫活体观察——体积定量法的进一步完善

尾草履虫Paramecium caudatun,属于原生动物纤毛纲,一直是动物学实验中不可缺少的实验材料.由于虫体游动快速,给活体观察实验带来了困难.近年来有一些关于草履虫观察方法的报导(黄丽清,2000;龚军辉,2003;吴美仙,2003;马惠钦等,2006;杨丽红,魏开,2007),但是这些方法仍具有一定的局限性.本研究室在前人工作的基础上,总结并报告了活体观察草履虫的一套方法,包括体积定量法、矿物油封闭法和脱纤毛法(杨仙玉等,2008).体积定量法中,使用了22×22 mm2规格的盖玻片,观察效果良好.但是利用体积定量法对草履虫进行观察时,使用不同规格的盖玻片所需草履虫培养液的体积不同.本文针对4种规格的盖玻片,对所需最适草履虫培养液的体积进行了研究,扩充了体积定量法,为观察活体草履虫带来了更大的方便.     

用于活体测量哺乳动物幼崽体重和体长的一种简易装置

要对饲养笼中的哺乳动物幼崽进行体重和体形的测量,通常的方法是直接把幼崽拿出称量.而很多动物,如倭蜂猴(Nycticebus pygmaeus),很容易受到这种方法的影响,造成母体弃婴现象.为了对动物幼崽体重和体长数据进行最小化伤害的准确测量并维持其自然生长规律,本文对养殖笼加活动条进行简易改造,并引入了一种自制的简易测量钳.     

Coaxial Aerodynamically Assisted Bio‐jets: A Versatile Paradigm for Directly Engineering Living Primary Organisms

In this paper, a coaxial jetting methodology is demonstrated as a first example (non‐electric field driven) completely run by aerodynamic forces which are brought about by the application of a differential pressure for the safe handling of primary living organisms by means of jets as encapsulated droplets. Previously this jetting technique in this configuration has only been investigated for processing combinations of liquid‐liquid and liquid‐gas systems. These developmental studies into aerodynamically assisted jets (AAJ) have unearthed a versatile bio‐jetting approach referred to here as coaxial aerodynamically assisted bio‐jetting (CAABJ). In the current work, this flexible approach is demonstrated to handle two primary cell types for drop‐and‐placing onto several different substrates. Furthermore, the study assesses cellular viability of the post‐treated cells in comparison to controls by way of flow cytometry. These first steps demonstrate the promise this protocol has in exploring the creation of biologically viable structures to form encapsulations of cells which would be useful as a direct tissue engineering to the immuno‐hinding methodology in bio‐repair and therapeutics. Therefore, these investigations place CAABJ into the cell jetting pursuit together with bio‐electrosprays, which will undergo an explosive developmental research.     

Living Organ Procurement from the Mentally Incompetent: The Need for More Appropriate Guidelines

With the case of Belgium as a negative example, this paper will evaluate the legitimacy of using mentally incompetents as organ sources. The first section examines the underlying moral dilemma that results from the necessity of balancing the principle of respect for persons with the obligation to help people in desperate need. We argue for the rejection of a radical utilitarian approach but also question the appropriateness of a categorical prohibition. Section two aims to strike a fair balance between the competing interests at stake and to define the conditions under which organ harvest from mentally incompetents might be morally acceptable. To this end, we morally assess the main requirements that have been put forward to allow organ removal from incompetent donors. We conclude that the current Belgian legislation is far too permissive and that national regulations that do not permit the harvest of non‐regenerable organs from mentally incompetents in exceptional circumstances are too restrictive. On the basis of this discussion, we propose a number of guiding principles for decision‐making in this area.     

Computerised Decision Support System for Remote Health Monitoring: A Systematic Review

Background

Remote health monitoring plays a major role in handling the critical situation of patients and avoiding death and also enhancing the quality of healthcare services. The effective real time monitoring with accurate decision has to be made in advance with the help of decision making system by continuously acquiring biosignals.

A Rule-Based Decision Support System for Critical Infrastructure Management

This article presents a new rule-based decision support system for critical infrastructure management based on the interdependencies among critical infrastructures. Unlike the conventional flood front prediction model, the new failure front prediction model consists of both physical parameters and interdependencies among infrastructures, which is represented by a multi-level complex network. This study employs advanced computation methods to build tools for better understanding emergent behavior of water security infrastructure systems for use in developing superior preparedness and response strategies. This study highlights the important role played by the interdependencies among the infrastructures in failure front prediction.     

Optimal Sensor Placement in Smart Home Using Building Information Modeling: A Home Support Application

ObjectivesIn this paper, we present a plugin for the optimal placement of sensors in a smart home. Our approach includes the Building Information Modeling (BIM) which is a plan that describes the building layout.Material and methodsThis plugin uses the CSTB EveBim viewer for loading IFC file representing the digital building's model. We use then, a mathematical model based on a mixed integer linear program, to determine the optimal sensor placement according to building and sensors characteristics.ResultsThe results show the efficiency of the proposed algorithm and the developed plugin. We obtain an optimal solution after few seconds, and we show the sensor placement on the building digital model.ConclusionWe show the relevance of the proposed plugin to equip room of retirement home or ambient assisted living in order to identify occupant activity for home support application.     

A Conservation Institution for the 21st Century: Implications for State Wildlife Agencies

ABSTRACT The wildlife conservation institution (Institution) needs to reform to maintain legitimacy and relevancy in the 21st century. Institutional reform is inherently slow. Limitations resulting from historical and resource dependencies between state wildlife agencies and hunters have left the Institution poorly positioned to meet changing ecological and social complexities. In this paper, we suggest that an ideal Institution would have the following 4 components: broad-based funding, trustee-based governance, multidisciplinary science as the basis of recommendations from professional staff, and involvement of diverse stakeholders and partners. Our suggestions reflect the fundamental tenets of the Public Trust Doctrine, which we believe is the foundation of the Institution. In bringing forth these ideas, we hope to encourage discussion about how the Institution should reform to meet the changing needs of society.     

Establishment and Growth of Living Fence Species: An Overlooked Tool for the Restoration of Degraded Areas in the Tropics

Numerous tree species can establish by vegetative means in the tropics. Many are used in agriculture as living fences and in alley cropping and could also be used in a restorational setting. However, little is known about their establishment ability. This study evaluated the establishment ability and cover development of multiple species in three separate field trials in northern Honduras. First, 11 species were evaluated for their ability to establish in a common garden experiment. Second, of the former species, Bursera simaruba and Gliricidia sepium were evaluated for 2 years for their ability to establish vegetatively and develop cover at three deforested sites. Lastly, a study examined whether greater initial stake height and diameter at breast height increased the establishment success and crown development of G. sepium stakes. First, five species, Erythrina berteroana, Erythrina fusca, Jatropha curcas, G. sepium, and B. simaruba, had high establishment success. Others showed promise but may have been planted in the wrong season. Second, establishment for G. sepium was nearly 100% at all sites, whereas B. simaruba ranged from 30–50%. Gliricidia sepium stakes developed more rapidly and attained greater cover than B. simaruba. Dry season planting may increase the establishment success of both species. Lastly, greater initial stake height and diameter at breast height each resulted in greater crown development for G. sepium. The use of living fence species as a restorational tool has been overlooked. Aside from the advantages of planting tree species vegetatively, species can act as seed recruitment foci by attracting seed dispersers and provide shade to improve microclimatic conditions for seedling establishment. The technique described is simple and could have broad application throughout tropical regions.     

Lack of Support for the Association between Facial Shape and Aggression: A Reappraisal Based on a Worldwide Population Genetics Perspective

Antisocial and criminal behaviors are multifactorial traits whose interpretation relies on multiple disciplines. Since these interpretations may have social, moral and legal implications, a constant review of the evidence is necessary before any scientific claim is considered as truth. A recent study proposed that men with wider faces relative to facial height (fWHR) are more likely to develop unethical behaviour mediated by a psychological sense of power. This research was based on reports suggesting that sexual dimorphism and selection would be responsible for a correlation between fWHR and aggression. Here we show that 4,960 individuals from 94 modern human populations belonging to a vast array of genetic and cultural contexts do not display significant amounts of fWHR sexual dimorphism. Further analyses using populations with associated ethnographical records as well as samples of male prisoners of the Mexico City Federal Penitentiary condemned by crimes of variable level of inter-personal aggression (homicide, robbery, and minor faults) did not show significant evidence, suggesting that populations/individuals with higher levels of bellicosity, aggressive behaviour, or power-mediated behaviour display greater fWHR. Finally, a regression analysis of fWHR on individual''s fitness showed no significant correlation between this facial trait and reproductive success. Overall, our results suggest that facial attributes are poor predictors of aggressive behaviour, or at least, that sexual selection was weak enough to leave a signal on patterns of between- and within-sex and population facial variation.     

NUCEL (Cell and Molecular Therapy Center): A Multidisciplinary Center for Translational Research in Brazil

Social and economical development is closely associated with technological innovation and a well-developed biotechnological industry. In the last few years, Brazil’s scientific production has been steadily increasing; however, the number of patents is lagging behind, with technological and translational research requiring governmental incentive and reinforcement. The Cell and Molecular Therapy Center (NUCEL) was created to develop activities in the translational research field, addressing concrete problems found in biomedical and veterinary areas and actively searching for solutions by employing a genetic engineering approach to generate cell lines over-expressing recombinant proteins to be transferred to local biotech companies, aiming at furthering the development of a national competence for local production of biopharmaceuticals of widespread use and of life-saving importance. To this end, mammalian cell engineering technologies were used to generate cell lines over-expressing several different recombinant proteins of biomedical and biotechnological interest, namely, recombinant human Amylin/IAPP for diabetes treatment, human FVIII and FIX clotting factors for hemophilia, human and bovine FSH for fertility and reproduction, and human bone repair proteins (BMPs). Expression of some of these proteins is also being sought with the baculovirus/insect cell system (BEVS) which, in many cases, is able to deliver high-yield production of recombinant proteins with biological activity comparable to that of mammalian systems, but in a much more cost-effective manner. Transfer of some of these recombinant products to local Biotech companies has been pursued by taking advantage of the São Paulo State Foundation (FAPESP) and Federal Government (FINEP, CNPq) incentives for joint Research Development and Innovation partnership projects.     

Evaluating the Evidence for Hormesis: A Statistical Perspective

It is possible to account for hormesis under current regulatory guidelines by invoking criteria for departure from default risk assessment procedures. However, past experience suggests that it will be difficult to amass enough evidence for hormesis in an individual case to permit departure from default procedures. Accordingly, hormesis is likely to be important in agency risk assessments only if guidelines are modified to incorporate hormesis as a default assumption. This could be appropriate if hormesis is determined to be a universal or near-universal phenomenon. Although there is ample evidence that hormesis occurs in many specific situations, the overall prevalence of hormesis is very difficult to evaluate based on currently available data. The lack of a valid statistical test for hormesis is a major limitation when evaluating evidence for hormesis. The attempts at estimating the prevalence of hormesis reviewed herein did not adequately control for false positives and/or may have had inadequate power to detect hormesis. Some suggestions are made for constructing a database and analyzing the data therein that would provide more readily interpretable information on the prevalence of hormesis.     

苏云金杆菌杀虫晶体蛋白活性预测的支持向量机模型

藉均匀设计(UD)方法,构建了苏云金杆菌(Bt)杀虫晶体蛋白氨基酸组成特征与其杀虫活性之间关系的支持向量机(SVM)模型。当惩罚系数为0·01、epsilon值为0·2、gamma值为0·05、域值为0·5时,该模型对Bt杀虫晶体蛋白杀虫活性的预测平均准确率达73%。     

A Nonadiabatic Theory for Ultrafast Catalytic Electron Transfer: A Model for the Photosynthetic Reaction Center

A non-adiabatic theory of Electron Transfer (ET), which improves the standard theory near the inversion point and becomes equivalent to it far from the inversion point, is presented. The complex amplitudes of the electronic wavefunctions at different sites are used as Kramers variables for describing the quantum tunneling of the electron in the deformable potential generated by its environment (nonadiabaticity) which is modeled as a harmonic classical thermal bath. After exact elimination of the bath, the effective electron dynamics is described by a discrete nonlinear Schrödinger equation with norm preserving dissipative terms and a Langevin random force, with a frequency cut-off, due to the thermalized phonons. This theory reveals the existence of a specially interesting marginal case when the linear and nonlinear coefficients of a two electronic states system are appropriately tuned for forming a Coherent Electron-Phonon Oscillator (CEPO). An electron injected on one of the electronic states of a CEPO generates large amplitude charge oscillations (even at zero temperature) associated with coherent phonon oscillations and electronic level oscillations. This fluctuating electronic level may resonate with a third site which captures the electron so that Ultrafast Electron Transfer (UFET) becomes possible. Numerical results are shown where two weakly interacting sites, a donor and a catalyst, form a CEPO that triggers an UFET to an acceptor. Without a catalytic site, a very large energy barrier prevents any direct ET. This UFET is shown to have many qualitative features similar to those observed in the primary charge separation in photosynthetic reaction centers. We suggest that more generally, CEPO could be a paradigm for understanding many selective chemical reactions involving electron transfer in biosystems.     

Graphdiyne: A Rising Star of Electrocatalyst Support for Energy Conversion

Graphdiyne (GDY), a rising star of 2D carbon allotropes with one‐atom‐thick planar layers, has achieved the coexistence of sp‐ and sp²‐hybridized carbon atoms in a 2D planar structure. In contrast to the prevailing carbon allotropes, GDY possesses Dirac cone structures, which endow it with unique chemical and physical properties, including an adjustable inherent bandgap, high‐speed charge carrier transfer efficiency, and excellent conductivity. Additionally, GDY also displays great potential in photocatalysis, rechargeable batteries, solar cells, detectors, and especially electrocatalysis. In this work, various GDY‐supported electrocatalysts are described and the reasons why GDY can act as a novel support are analyzed from the perspective of molecular structure, electronic properties, mechanical properties, and stability. The various electrochemical applications of GDY‐supported electrocatalysts in energy conversion such as hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, overall water splitting, and nitrogen reduction reaction are reviewed. The challenges facing GDY and GDY‐based materials in future research are also outlined. This review aims at providing an in‐depth understanding of GDY and promoting the development and application of this novel carbon material.     

Large-scale Transient Transfection of Mammalian Cells: A Newly Emerging Attractive Option for Recombinant Protein Production

Mammalian expression systems have an undisputed long-standing and very successful history for the generation of recombinant proteins, mainly as biopharmaceuticals. However, for use as ‘tool proteins’ in, e.g. assay development and screening, for structure elucidation and as antigens these expression systems were generally regarded as being cumbersome, tedious and expensive. This bias has largely been overcome with the very recent development of large-scale transient transfection (LST) approaches. Especially the HEK.EBNA expression system described here has contributed significantly to this success. The simplicity and speed of this approach compares well with expression trials using the widely applied Baculovirus/insect cell system. In addition, proteins generated in mammalian cells are usually correctly folded, fully processed and functionally active.     

Effects of Precise Deletions in Rhodobacter sphaeroides Reaction Center Genes on Steady-state Levels of Reaction Center Proteins: A Revised Model for Reaction Center Assembly

Possible interactions between photosynthetic reaction center (RC) proteins that protect these membrane proteins from proteolytic digestion in RC complex assembly were evaluated by use of translationally in-frame (nonpolar) RC gene-specific deletions. The RC H, RC M and RC L proteins were produced from plasmids, either alone or in concert with one or both of the others, in a strain of Rhodobacter sphaeroides that contained chromosomal deletions of all three RC genes. The steady-state amounts of these proteins in cell membrane and soluble fractions were assessed in western blots. The data are used to propose a model of RC assembly in which the RC M protein accumulates in the cell membrane regardless of the presence of the RC H and RC L proteins, and the RC M protein is a nucleus for addition of RC L followed by RC H in assembly of the RC holocomplex.     

Question 7: Construction of a Semi-Synthetic Minimal Cell: A Model for Early Living Cells

Using a Synthetic Biology approach we are building a semi-synthetic minimal cell. This represents an exercise to shape a minimal-cell model system recalling the simplicity of early living cells in early evolution. We have recently introduced into liposome compartments a minimal set of enzymes named “Puresystem” (PS) synthesizing EGFP proteins. To establish reproduction of the shell compartment with a minimal set of genes we have cloned the genes for the Fatty Acid Synthase (FAS) type I enzymes. These FAS genes introduced into liposomes, translated into FAS enzymes by PS and in the presence of precursors produce fatty acids. The resulting release of fatty acid molecules within liposome vesicles should promote vesicle growth and reproduction. The core reproduction of a minimal cell corresponding to the replication of the minimal genome will require a few genes for the DNA replication and the PS, and a minimum set of genes for the synthesis of t-RNAs. In future the reconstruction of a minimal ribosome will bring the number of genes for ribosomal proteins from 54 of an existing minimal genome down to 30–20 genes. A Synthetic Biology approach could bring the number of essential genes for a minimal cell down to 100 or less. International School of Complexity–4th Course: Basic Questions on the Origins of Life; “Ettore Majorana” Foundation and Centre for Scientific Culture, Erice, Italy, 1–6 October 2006.     

一种检测细胞微量点突变的方法——等位基因特异的PCR

为了灵敏、方便地检测出细胞群体中含量极低的点突变,利用一β珠蛋白基因簇Gγ -202 C→G突变的杂合细胞株,优化传统的等位基因特异PCR的反应条件,以定量的PCR产物为模板,在含5%甲酰胺的体系中用半巢式的等位基因特异引物进行扩增.结果表明,该方法灵敏可靠,可快速检测到细胞群体中低于0.025%的点突变.