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Diverse Collection (diverse + collection)
Selected AbstractsForty-nine new host plant species for Bemisia tabaci (Hemiptera: Aleyrodidae)ENTOMOLOGICAL SCIENCE, Issue 4 2008Alvin M. SIMMONS Abstract The sweetpotato whitefly, Bemisia tabaci (Gennadius), is a worldwide pest of numerous agricultural and ornamental crops. In addition to directly feeding on plants, it also acts as a vector of plant viruses of cultivated and uncultivated host plant species. Moreover, host plants can affect the population dynamics of whiteflies. An open-choice screening experiment was conducted with B-biotype B. tabaci on a diverse collection of crops, weeds, and other indigenous plant species. Five of the plant species were further evaluated in choice or no-choice tests in the laboratory. The results reveal 49 new reproductive host plant species for B. tabaci. This includes 11 new genera of host plants (Arenaria, Avena, Carduus, Dichondra, Glechoma, Gnaphalium, Molugo, Panicum, Parthenocissus, Trianthema, and Triticum) for this whitefly. All species that served as hosts were acceptable for feeding, oviposition, and development to the adult stage by B. tabaci. The new hosts include three cultivated crops [oats (Avena sativa L.), proso millet (Panicum miliaceum L.), and winter wheat (Triticum aestivum L.)], weeds and other wild species, including 32 Ipomoea species, which are relatives of sweetpotato [I. batatas (L.) Lam.)]. Yellow nutsedge, Cyperus esculentus L., did not serve as a host for B. tabaci in either open-choice or no-choice tests. The results presented herein have implications for whitefly ecology and the numerous viruses that B. tabaci spreads to and among cultivated plants. [source] Kleptoplasty in an Antarctic dinoflagellate: caught in evolutionary transition?ENVIRONMENTAL MICROBIOLOGY, Issue 1 2007Rebecca J. Gast Summary Photosynthetic dinoflagellates contain a diverse collection of plastid types, a situation believed to have arisen from multiple endosymbiotic events. In addition, a number of heterotrophic (phagotrophic) dinoflagellates possess the ability to acquire chloroplasts temporarily by engulfing algae and retaining their chloroplasts in a functional state. These latter relationships typically last from a few days to weeks, at which point the chloroplasts lose function, are digested and replaced with newly acquired plastids. A novel and abundant dinoflagellate related to the icthyotoxic genera Karenia and Karlodinium was recently discovered by us in the Ross Sea, Antarctica. Sequencing of its plastid small subunit ribosomal gene indicated that it did not share evolutionary history with the plastids of Karenia or Karlodinium, but was closely related to the free-living haptophyte Phaeocystis antarctica, a species that often dominates phytoplankton blooms in the Ross Sea. Chloroplast uptake was observed to occur rapidly (within 2 days), with retention in cultures being long-lived (several months) but not permanent. The dinoflagellate was also incapable of growing indefinitely in continuous darkness with algae as prey. Our findings may indicate an emerging endosymbiotic event yielding a dinoflagellate that is presently neither purely phototrophic nor purely heterotrophic, but occupies a niche juxtaposed between these contrasting nutritional modes. [source] The academic environment: the students' perspectiveEUROPEAN JOURNAL OF DENTAL EDUCATION, Issue 2008K. Divaris (nci) Abstract Dental education is regarded as a complex, demanding and often stressful pedagogical procedure. Undergraduates, while enrolled in programmes of 4,6 years duration, are required to attain a unique and diverse collection of competences. Despite the major differences in educational systems, philosophies, methods and resources available worldwide, dental students' views regarding their education appear to be relatively convergent. This paper summarizes dental students' standpoint of their studies, showcases their experiences in different educational settings and discusses the characteristics of a positive academic environment. It is a consensus opinion that the ,students' perspective' should be taken into consideration in all discussions and decisions regarding dental education. Moreover, it is suggested that the set of recommendations proposed can improve students' quality of life and well-being, enhance their total educational experience and positively influence their future careers as oral health physicians. The ,ideal' academic environment may be defined as one that best prepares students for their future professional life and contributes towards their personal development, psychosomatic and social well-being. A number of diverse factors significantly influence the way students perceive and experience their education. These range from ,class size', ,leisure time' and ,assessment procedures' to ,relations with peers and faculty', ,ethical climate' and ,extra-curricular opportunities'. Research has revealed that stress symptoms, including psychological and psychosomatic manifestations, are prevalent among dental students. Apparently some stressors are inherent in dental studies. Nevertheless, suggested strategies and preventive interventions can reduce or eliminate many sources of stress and appropriate support services should be readily available. A key point for the Working Group has been the discrimination between ,teaching' and ,learning'. It is suggested that the educational content should be made available to students through a variety of methods, because individual learning styles and preferences vary considerably. Regardless of the educational philosophy adopted, students should be placed at the centre of the process. Moreover, it is critical that they are encouraged to take responsibility for their own learning. Other improvements suggested include increased formative assessment and self-assessment opportunities, reflective portfolios, collaborative learning, familiarization with and increased implementation of information and communication technology applications, early clinical exposure, greater emphasis on qualitative criteria in clinical education, community placements, and other extracurricular experiences such as international exchanges and awareness of minority and global health issues. The establishment of a global network in dental education is firmly supported but to be effective it will need active student representation and involvement. [source] Genetic and epigenetic aspects of bladder cancerJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 1 2005Wun-Jae Kim Abstract Transitional cell carcinoma of the urinary bladder has a diverse collection of biologic and functional characteristics. This is reflected in differing clinical courses. The diagnosis of bladder cancer is based on the information provided by cystoscopy, the gold standard in combination with urinary cytology findings. Many tumor markers have been evaluated for detecting and monitoring the disease in serum, bladder washes, and urinary specimens. However, none of these biomarkers reported to date has shown sufficient sensitivity and specificity for the detection of the whole spectrum of bladder cancer diseases in routine clinical practice. The limited value of established prognostic markers requires the analysis of new molecular parameters of interest in predicting the prognosis of bladder cancer patients; in particular, the high-risk patient groups at risk of progression and recurrence. Over the past decade, there has been major progress elucidating of the molecular genetic and epigenetic changes leading to the development of transitional cell carcinoma. This review focuses on the recent advances of genetic and epigenetic aspects in bladder cancer, and emphasizes how molecular biology would be likely to affect the future therapies. © 2005 Wiley-Liss, Inc. [source] The origami of thioredoxin-like foldsPROTEIN SCIENCE, Issue 10 2006Jonathan L. Pan Abstract Origami is the Japanese art of folding a piece of paper into complex shapes and forms. Much like origami of paper, Nature has used conserved protein folds to engineer proteins for a particular task. An example of a protein family, which has been used by Nature numerous times, is the thioredoxin superfamily. Proteins in the thioredoxin superfamily are all structured with a ,-sheet core surrounded with ,-helices, and most contain a canonical CXXC motif. The remarkable feature of these proteins is that the link between them is the fold; however, their reactivity is different for each member due to small variations in this general fold as well as their active site. This review attempts to unravel the minute differences within this protein family, and it also demonstrates the ingenuity of Nature to use a conserved fold to generate a diverse collection of proteins to perform a number of different biochemical tasks. [source] Quantitative analysis of neuronal diversity in the mouse olfactory bulbTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 6 2007S. Parrish-Aungst Abstract Olfactory sensory information is processed and integrated by circuits within the olfactory bulb. Golgi morphology suggests the olfactory bulb contains several major neuronal classes. However, an increasingly diverse collection of neurochemical markers have been localized in subpopulations of olfactory bulb neurons. While the mouse is becoming the animal model of choice for olfactory research, little is known about the proportions of neurons expressing and coexpressing different neurochemical markers in this species. Here we characterize neuronal populations in the mouse main olfactory bulb, focusing on glomerular populations. Immunofluorescent labeling for: 1) calretinin, 2) calbindin D-28K (CB), 3) parvalbumin, 4) neurocalcin, 5) tyrosine hydroxylase (TH), 6) the 67-kDa isoform of GAD (GAD67), and 7) the neuronal marker NeuN was performed in mice expressing green fluorescent protein under the control of the glutamic acid decarboxylase 65kDa (GAD65) promoter. Using unbiased stereological cell counts we estimated the total numbers of cells and neurons in the bulb and the number and percentage of neurons expressing and coexpressing different neurochemical populations in each layer of the olfactory bulb. Use of a genetic label for GAD65 and immunohistochemistry for GAD67 identified a much larger percentage of GABAergic neurons in the glomerular layer (55% of all neurons) than previously recognized. Additionally, while many glomerular neurons expressing TH or CB coexpress GAD, the majority of these neurons preferentially express the GAD67 isoform. These data suggest that the chemospecific populations of neurons in glomeruli form distinct subpopulations and that GAD isoforms are preferentially regulated in different neurochemical cell types. J. Comp. Neurol. 501:825,836, 2007. © 2007 Wiley-Liss, Inc. [source] Applications of Multicomponent Reactions to the Synthesis of Diverse Heterocyclic ScaffoldsCHEMISTRY - A EUROPEAN JOURNAL, Issue 6 2009James Abstract The sequencing of multicomponent reactions (MCRs) and subsequent cyclization reactions is a powerful stratagem for the rapid synthesis of diverse heterocyclic scaffolds. The optimal MCR is sufficiently flexible that it can be employed to generate adducts bearing a variety of functional groups that may then be selectively paired to enable different cyclization manifolds, thereby leading to a diverse collection of products. The growing interest in diversity-oriented synthesis has led to increased attention to this paradigm for library synthesis, which has inspired many advances in the design and implementation of MCRs for the construction of diverse heterocyclic scaffolds. [source] | |||||||||||||