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The Short ITS2 Sequence Serves as an Efficient Taxonomic Sequence Tag in Comparison with the Full-Length ITS
No full textAn ideal DNA barcoding region should be short enough to be ampli�ed from degraded DNA. In this paper, we discuss the possibility of using a short nuclear DNA sequence as a barcode to identify a wide range of medicinal plant species. First, the PCR and sequencing success rates of ITS and ITS2 were evaluated based entirely on materials from dry medicinal product and herbarium voucher specimens, including some samples collected back to 90 years ago. e results showed that ITS2 could recover 91% while ITS could recover only 23% efficiency of PCR and sequencing by using one pair of primer. Second, 12861 ITS and ITS2 plant sequences were used to compare the identi�cation efficiency of the two regions. Four identi�cation criteria (BLAST, inter-and intradivergence Wilcoxon signed rank tests, and TaxonDNA) were evaluated. Our results supported the hypothesis that ITS2 can be used as a minibarcode to effectively identify species in a wide variety of specimens and medicinal materials
STUDIES ON NORTH AMERICAN PECOPTERIDS. III. PECOPTERIS BUTTSII D. WHITE FROM THE EARLY PENNSYLVANIAN OF ALABAMA
No full textJSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. . ABSTRACT-The form genus Pecopteris Brongniart is rare in Lower Pennsylvanian strata. Those species originally described from North America need to be reinvestigated to determine their relationship to the more extensively described European forms. The occurrence of early Pennsylvanian pecopterids is significant because they represent the early history of this group, which becomes dominant in the Westphalian D. SEPM Society for Sedimentary Geology Pecopteris buttsii D. White was originally established for a lobate pinnuled pecopterid from the Brookwood coal horizon (New River equivalent, Westphalian A), Warrior coalfield, Alabama. The species was invalidly published and a study of the type specimen was initiated to discern its affinity. Attempts at collecting additional specimens from the type area have failed and the formal description is based upon fragments of seven third or possibly fourth order (?) pinnae. Additional specimens of P. buttsii (?) from Tennessee were also examined to discern their relationship with the holotype. Consideration of parameters necessary to erect form taxa is highly complex and many factors must be assessed prior to establishment of a new form. These parameters include the degree of morphological homology between specimens and their reported temporal isolation or continuation. Frequency of occurrence should not be considered as a delimiting character nor should size or preservational configuration
Study of Scattering by Surface Acoustic Wave Motor Slider Using Finite Element Method Simulation
No full textA surface acoustic wave (SAW) motor has already shown its superior potential. However, its efficiency from the electrical input to the mechanical output is still low. To improve its efficiency, an energy circulation driving method has been proposed and demonstrated. It has been found that the Rayleigh wave beneath the slider was scattered, so that the phase of the wave shifted; the phase shift decreased the efficiency of the motor. Thus, we need to know the characteristics of the phase shift to design a SAW motor with a high efficiency. From several experimental results, it has been found that the phase shift is related to the projection parameters of the slider and the preload conditions. The relationship between the slider projection contact, the friction phenomenon, and the phase shift was investigated by numerical simulation using the finite element method. Twodimensional finite element method analysis in a time domain was carried out to simulate the wave propagation from driving points through a preloaded silicon slider. Contact and friction simulation was applied to the boundary condition between the stator and the slider projections
The Anatomy of a Design Theory The Anatomy of a Design Theory
No full textDesign work and design knowledge in Information Systems (IS) is important for both research and practice. Yet there has been comparatively little critical attention paid to the problem of specifying design theory so that it can be communicated, justified, and developed cumulatively. In this essay we focus on the structural components or anatomy of design theories in IS as a special class of theory. In doing so, we aim to extend the work of Walls, Widemeyer and El Sawy (1992) on the specification of information systems design theories (ISDT), drawing on other streams of thought on design research and theory to provide a basis for a more systematic and useable formulation of these theories. We identify eight separate components of design theories: (1) purpose and scope, (2) constructs, (3) principles of form and function, (4) artifact mutability, (5) testable propositions, (6) justificatory knowledge (kernel theories), (7) principles of implementation, and (8) an expository instantiation. This specification includes components missing in the Walls et al. adaptation o
A: Cross-cultural adaptation in urban ethnobotany: The Colombian folk pharmacopoeia in London
No full texta b s t r a c t Aim of the study: To investigate traditional health care practices and changes in medicinal plant use among the growing Colombian community in London. Materials and methods: Ethnobotanical fieldwork consisted of qualitative, in-depth, semi-structured interviews with 23 Colombians living in London and botanical identification of 46 plant species actively used as herbal remedies. Subsequently, research data were compared with literature on ethnobotany and traditional herbal medicine in the home country, using a framework on cross-cultural adaptation, adjusted for the purpose of this study. Results: Similarities and discrepancies between data and literature are interpreted as potential indicators of continuity and loss (or deculturation) of traditional remedies, respectively. Remedies used in London that are not corroborated by the literature suggest possible newly acquired uses. Conclusions: Cross-cultural adaptation related to health care practices is a multifaceted process. Persistence, loss and incorporation of remedies into the Colombian folk pharmacopoeia after migration are influenced by practical adaptation strategies as well as by symbolic-cultural motives of ethnic identity
The Cysteine Protease Inhibitor, E-64, Stimulates the Polarization and Locomotor Responses of Endothelial Cells to Wounding1
No full textArticle Mathematical Modeling of the Heat-Shock Response in HeLa Cells
No full textABSTRACT The heat-shock response is a key factor in diverse stress scenarios, ranging from hyperthermia to protein folding diseases. However, the complex dynamics of this physiological response have eluded mathematical modeling efforts. Although several computational models have attempted to characterize the heat-shock response, they were unable to model its dynamics across diverse experimental datasets. To address this limitation, we mined the literature to obtain a compendium of in vitro hyperthermia experiments investigating the heat-shock response in HeLa cells. We identified mechanisms previously discussed in the experimental literature, such as temperature-dependent transcription, translation, and heat-shock factor (HSF) oligomerization, as well as the role of heat-shock protein mRNA, and constructed an expanded mathematical model to explain the temperature-varying DNA-binding dynamics, the presence of free HSF during homeostasis and the initial phase of the heat-shock response, and heat-shock protein dynamics in the long-term heat-shock response. In addition, our model was able to consistently predict the extent of damage produced by different combinations of exposure temperatures and durations, which were validated against known cellular-response patterns. Our model was also in agreement with experiments showing that the number of HSF molecules in a HeLa cell is roughly 100 times greater than the number of stress-activated heat-shock element sites, further confirming the model's ability to reproduce experimental results not used in model calibration. Finally, a sensitivity analysis revealed that altering the homeostatic concentration of HSF can lead to large changes in the stress response without significantly impacting the homeostatic levels of other model components, making it an attractive target for intervention. Overall, this model represents a step forward in the quantitative understanding of the dynamics of the heat-shock response
Monostable-Type Travelling Wave Solutions of the Diffusive FitzHugh-Nagumo-Type System in R
No full textThis paper is concerned with monostable-type travelling wave solutions of the diffusive FitzHughNagumo-type system FHN in R N for the two components u and v. By solving v in terms of u, this system can be reduced to a nonlocal single equation for u. When the diffusion coefficients in the system are equal, we construct travelling wave solutions for the non-local equation by the method of super-and subsolutions developed by Morita and Ninomiya 2008 Moreover, we propose a condition for γ, which is similar to the condition Reinecke and Sweers 1999 used to transform FHN into a quasimonotone system