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Necessary Tools (necessary + tool)
Selected AbstractsComparative study and molecular characterization of ectomycorrhizas in Tilia americana and Quercus pubescens with Tuber brumaleFEMS MICROBIOLOGY LETTERS, Issue 1 2002G Giomaro Abstract Mycorrhizas of Tuber brumale on Quercus pubescens and Tilia americana were obtained in vitro using micropropagated plantlets. Mycelium pure cultures were used for inoculation. Both the mycelium used for the inoculations, as well as the mycorrhizas which were obtained, were identified using several molecular approaches: analysis of the ITS region, polymerase chain reaction (PCR) specific primers and sequencing. The mycorrhizas were described from a morphological standpoint. Some of their biometric characteristics were different in bass-wood than they were in oak, thus showing the influence of the host plant on several of the morphological features believed to be necessary for the identification of the species. Considering the variability of their morphological characteristics, molecular analysis proved to be a necessary tool for the recognition of the mycorrhizas of Tuber spp. [source] Phenotypic study by numerical taxonomy of strains belonging to the genus AeromonasJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2002L. Valera Aims: ,This study was undertaken to cluster and identify a large collection of Aeromonas strains. Methods and Results: ,Numerical taxonomy was used to analyse phenotypic data obtained on 54 new isolates taken from water, fish, snails, sputum and 99 type and reference strains. Each strain was tested for 121 characters but only the data for 71 were analysed using the `SSM' and `SJ' coefficients, and the UPGMA clustering algorithm. At SJ values of , 81·6% the strains clustered into 22 phenons which were identified as Aer. jandaei, Aer. hydrophila, Aer. encheleia, Aer. veronii biogroup veronii, Aer. trota, Aer. caviae, Aer. eucrenophila, Aer. ichthiosmia, Aer. sobria, Aer. allosaccharophila, Aer. media, Aer. schubertii and Aer. salmonicida. The species Aer. veronii biogroup sobria was represented by several clusters which formed two phenotypic cores, the first related to reference strain CECT 4246 and the second related to CECT 4835. A good correlation was generally observed among this phenotypic clustering and previous genomic and phylogenetic data. In addition, three new phenotypic groups were found, which may represent new Aeromonas species. Conclusions: ,The phenetic approach was found to be a necessary tool to delimitate and identify the Aeromonas species. Significance and Impact of the Study: ,Valuable traits for identifying Aeromonas as well as the possible existence of new Aeromonas species or biotypes are indicated. [source] The use of chronosequences in studies of ecological succession and soil developmentJOURNAL OF ECOLOGY, Issue 4 2010Lawrence R. Walker Summary 1.,Chronosequences and associated space-for-time substitutions are an important and often necessary tool for studying temporal dynamics of plant communities and soil development across multiple time-scales. However, they are often used inappropriately, leading to false conclusions about ecological patterns and processes, which has prompted recent strong criticism of the approach. Here, we evaluate when chronosequences may or may not be appropriate for studying community and ecosystem development. 2.,Chronosequences are appropriate to study plant succession at decadal to millennial time-scales when there is evidence that sites of different ages are following the same trajectory. They can also be reliably used to study aspects of soil development that occur between temporally linked sites over time-scales of centuries to millennia, sometimes independently of their application to shorter-term plant and soil biological communities. 3.,Some characteristics of changing plant and soil biological communities (e.g. species richness, plant cover, vegetation structure, soil organic matter accumulation) are more likely to be related in a predictable and temporally linear manner than are other characteristics (e.g. species composition and abundance) and are therefore more reliably studied using a chronosequence approach. 4.,Chronosequences are most appropriate for studying communities that are following convergent successional trajectories and have low biodiversity, rapid species turnover and low frequency and severity of disturbance. Chronosequences are least suitable for studying successional trajectories that are divergent, species-rich, highly disturbed or arrested in time because then there are often major difficulties in determining temporal linkages between stages. 5.,Synthesis. We conclude that, when successional trajectories exceed the life span of investigators and the experimental and observational studies that they perform, temporal change can be successfully explored through the judicious use of chronosequences. [source] Three-dimensional inversion of automatic resistivity profiling dataARCHAEOLOGICAL PROSPECTION, Issue 4 2009Nikos G. Papadopoulos Abstract Geophysical investigations through mobile multi-electrode systems, such as the automatic resistivity profiling (ARP) method, can increase the size of the surveyed areas without jeopardizing the spatial resolution of the survey. The representation of the apparent resistivity data in maps corresponding to the different measuring dipoles is sufficient in most routine applications for outlining the buried archaeological structures. In specific cases where a more quantitative interpretation of the apparent resistivity data is demanded, a three-dimensional resistivity inversion can provide the necessary tool for this purpose. This work investigates the possibilities and limitations of the three-dimensional resistivity inversion in processing the ARP data. A three-dimensional finite element smoothness-constrained inversion algorithm was used. The active constraint balancing (ACB) method was also applied in order to enhance the stability and the resolving power of the inversion procedure. Resistivity models that are commonly encountered in archaeological exploration were used to generate synthetic apparent resistivity data using a three-dimensional finite element forward modelling program. Inversion of the synthetic data showed that the maximum investigation depth of the ARP method is comparable to the length of the larger receiving dipole and cannot exceed the 2,2.5,m for the particular ARP device tested in this work. Archaeological structures buried within this depth range can be effectively mapped, while the resolution of the subsurface structures is related to the data acquisition parameters. The inversion algorithm was also used to reconstruct the three-dimensional resistivity distribution from the ARP data set collected from the Andilly archaeological site in France. The results effectively showed that the three-dimensional inversion can act as a complementary tool in acquiring a more quantitative interpretation model of the buried archaeological features. Copyright © 2009 John Wiley & Sons, Ltd. [source] Toward a semantic general theory of everythingCOMPLEXITY, Issue 4 2010Alexei V. Samsonovich The notion of a universal semantic cognitive map is introduced as a general indexing space for semantics, useful to reduce semantic relations to geometric and topological relations. As a first step in designing the concept, the notion of semantics is operationalized in terms of human subjective experience and is related to the concept of spatial position. Then synonymy and antonymy are introduced in geometrical terms. Further analysis building on previous studies of the authors indicates that the universal semantic cognitive map should be locally low-dimensional. This essay ends with a proposal to develop a metric system for subjective experiences based on the outlined approach. We conclude that a computationally defined universal semantic cognitive map is a necessary tool for the emerging new science of the mind: a scientific paradigm that includes subjective experience as an object of study. © 2009 Wiley Periodicals, Inc. Complexity, 2010 [source] The UK National Cancer Research Institute (NCRI) Informatics Initiative: promoting partnership in cancer research,HUMAN MUTATION, Issue 12 2007Fiona Reddington Abstract The vast amount of information emerging from cancer research in recent years has presented a challenge for researchers worldwide. The opportunities for using this data to enhance understanding of the disease and advance the delivery of novel anticancer treatments are greater than ever, but will fail to be fully realized unless the necessary tools to collate and analyze the information are developed. This article describes the work of the National Cancer Research Institute (NCRI) Informatics Initiative which aims to maximize the impact of the results of research funded by NCRI Partner organizations for the benefit of cancer patients by ensuring that data generated through research is put to maximum use by the cancer research community. Hum Mutat 28(12), 1151,1155, 2007. © 2007 Wiley-Liss, Inc. [source] Multiplex PCR detection of slowly-evolving trypanosomatids and neogregarines in bumblebees using broad-range primersJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2010I. Meeus Abstract Aims:, The aims of this study were to design universal markers for different protozoan parasites of Bombus spp. based on the phylogenetic position of two important bumblebee parasites Crithidia bombi and Apicystis bombi. Methods and Results:, Standard PCR and extraction techniques were used to amplify and sequence 18S rDNA. Phylogenetic analysis of the rDNA was performed in order to predict the parasite range of the primers. Conclusions:,Crithidia bombi phylogenetically clusters with the trypanosomatids with slowly-evolving SSU-rRNA sequences (SE), while A. bombi is the closest sister group of Mattesia. A multiplex was designed containing an internal control and two broad-range primer pairs, detecting C. bombi and other SE trypanosomatids and also A. bombi and other neogregarines. Significance and Impact of the Study:, Sequence data generated will further improve the current systematics of insect trypanosomatids and gregarines that remain troublesome. Broad-range markers for bumblebee parasites are necessary tools enabling the screening of commercially imported colonies and thus controlling their worldwide distribution and to discover related emerging parasites. [source] Population dynamics of fisheries stock enhancementJOURNAL OF FISH BIOLOGY, Issue 2004K. Lorenzen The population dynamics of fisheries stock enhancement, and its potential for generating benefits over and above those obtainable from optimal exploitation of wild stocks alone are poorly understood and highly controversial. I extend the dynamic pool theory of fishing to stock enhancement by unpacking recruitment, incorporating regulation in the recruited stock, and accounting for biological differences between wild and hatchery fish. I then analyse the dynamics of stock enhancement and its potential role in fisheries management, using the candidate stock of North Sea sole as an example. Enhancement through release of recruits or advanced juveniles is predicted to increase total yield and stock abundance, but reduce abundance of the naturally recruited stock component through compensatory responses or overfishing. Release of genetically maladapted fish reduces the effectiveness of enhancement, and is most detrimental overall if fitness of hatchery fish is only moderately compromised. As a temporary measure for rebuilding of depleted stocks, enhancement can not substitute for effort limitation, and is advantageous as an auxiliary measure only if the population has been reduced to a very low proportion of its unexploited biomass. Quantitative analysis of population dynamics is central to the responsible use of stock enhancement in fisheries management, and the necessary tools are available. [source] Virtual Shop Clusters: A New Layout Concept for a Ship Repair and Maintenance FacilityNAVAL ENGINEERS JOURNAL, Issue 2 2008BRIAN MAYER Organic ship maintenance facilities and depots of the Navy are mostly organized as trade-specific shops rather than by product (or process) families. For example, welders are in the weld shop, machinists are in the machine shop, pipe-fitters are in the pipe shop, etc. There is a belief that this guild-type organizational structure is what enables a repair facility to do almost anything, albeit at the cost of moving product all over the "factory." This skill-based organizational structure is identical to the functional (or department) layout that is preferred by most jobshops in the commercial manufacturing sectors. But, any company that has successfully implemented Lean Thinking has almost always replaced a Functional (or Process Village) Layout by a Cellular Layout. At the Navy's Southeast Regional Maintenance Center (SERMC), a typical repair job must visit multiple shops that pass work back and forth between them. For example, a pipe job may be sent by the pipe shop to the machine shop for re-threading, then routed to the weld shop where it is welded to a frame, after which the welded sub-assembly returns to the pipe shop for inspection and final assembly. Thereby, significant delays and operational wastes occur because people have to walk between the shops, discuss matters at daily production meetings, and e-mail/phone each other to make sure that their schedules match. If activities are not completed as per schedule, the jobs get further delayed because they queue at the shops, waiting to be served. This lack of detailed (and accurate) planning and scheduling, combined with poor schedule visibility and shop floor control, is the curse of the Functional Layout that currently exists at SERMC. This paper will describe a pilot project to assess the feasibility of cellular manufacturing at SERMC. The fundamental hypothesis that was tested is that even in a repair and maintenance facility there could exist several families of repair jobs where jobs grouped into a family require similar combinations of processes, equipment, materials, etc. that can be provided by a small group of shops. In fact, several potential families of repair jobs, and the appropriate cluster of shops for each family of repair jobs, were identified using the Production Flow Analysis and Simplification Toolkit (PFAST) software. Based on these results, it was decided to implement a shop cluster (or focused factory, or repair cell) to complete any repair jobs done by the dive shop. It was recommended that the dive shop be merged with a few other shops, and be provided the necessary tools, cross-trained personnel, equipment, and other support systems to become an autonomous multi-function shop. Simulation using the SimCAD software from CreateAsoft Inc. (http://www.createasof.com) was used to verify the results expected from making the proposed changes. The primary analysis was intended to evaluate the benefits of implementing a focused factory in the dive shop. The secondary analysis was intended to evaluate the advantages of implementing a virtual shop cluster (or focused factory, or repair cell) in any ship repair facility like SERMC. The simulation results showed that implementing either physical cells or virtual cells based on the different families of repair jobs identified by PFAST could improve job turnaround times at any Navy ship repair facility like SERMC. Both the types of delays as well as the time values of these delays differed significantly across the existing and alternative shop configurations that were proposed. [source] Moss Systems Biology en Route: Phytohormones in Physcomitrella DevelopmentPLANT BIOLOGY, Issue 3 2006E. L. Decker Abstract: The moss Physcomitrella patens has become a powerful model system in modern plant biology. Highly standardized cell culture techniques, as well as the necessary tools for computational biology, functional genomics and proteomics have been established. Large EST collections are available and the complete moss genome will be released soon. A simple body plan and the small number of different cell types in Physcomitrella facilitate the study of developmental processes. In the filamentous juvenile moss tissue, developmental decisions rely on the differentiation of single cells. Developmental steps are controlled by distinct phytohormones and integration of environmental signals. Especially the phytohormones auxin, cytokinin, and abscisic acid have distinct effects on early moss development. In this article, we review current knowledge about phytohormone influences on early moss development in an attempt to fully unravel the complex regulatory signal transduction networks underlying the developmental decisions of single plant cells in a holistic systems biology approach. [source] Epidemiology: Theory, study design, and planning for educationTHE JOURNAL OF CONTINUING EDUCATION IN THE HEALTH PROFESSIONS, Issue 3 2000PhD Assistant Professor, Shelley A. Harris MSc Abstract Many health professionals have received formal training in epidemiology; however, much of it has been limited to introductory courses at the undergraduate level. Further, continuing education for health professionals has focused historically on substantive rather than methodologic issues in epidemiology. A methodologic focus is recommended to improve continuing education for the health of the public. It is crucial to equip educators and health professionals with the necessary tools or resources to understand study design, conduct research, analyze and interpret data, and critically evaluate published research. Thus, in this article, a general overview of epidemiologic study design and some of the most common methodologic issues are presented. Issues such as confounding, effect modification, measurement error, and power and sample size are highlighted. A broader recognition of these issues by educators and health professionals may ultimately help to improve public health by facilitating effective educational interventions, proper study design, analysis, interpretation, and application of epidemiologic research. [source] Conservation diagnosis of reintroducing Mediterranean pond turtles: what is wrong?ANIMAL CONSERVATION, Issue 6 2009A. Bertolero Abstract The presence of the Mediterranean pond turtle Mauremys leprosa in the Ebre Delta (Catalonia, north-east Spain) is well documented after the late 1970s, when the first reptile distribution lists were published. Owing to the fact that the species was considered scarce, a reintroduction programme based on the release of individuals at sites with potential habitat suitability was launched. From 1999 to 2001, 234 turtles of different ages were released and subsequently monitored until 2007, in order to make a conservation diagnosis using five assessment criteria. These criteria were body condition, individual growth, reproduction, survival and population growth rate. Despite the relatively large number of turtles released, no viable population resulted from the programme. Assessment criteria suggested that: (1) released individuals showed good physical condition and satisfactory growth (the only positive results); (2) reproduction was almost absent; (3) local survival was reduced compared with that of Spanish wild populations of the species; (4) temporary emigration was high; (5) the growth rate of the population was negative. In conclusion, the results suggested that the habitat at the Ebre Delta marshes may not be favourable to the species, and that the scarce historical data record may indicate a relatively low-quality habitat; the few records may correspond to individuals dispersing from the river, a more suitable habitat. Thus, we conclude that historically scarce records may be the result of natural patchiness and heterogeneous distributions, and they are not necessarily a good indicator of relict, decimated populations. Good assessment criteria, as those proposed and used here, are necessary tools to assess results in reintroduction projects to recover endangered chelonian populations. [source] | |||||||||||||