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91.
92.
Rebecca McLain Melissa Poe Kelly Biedenweg Lee Cerveny Diane Besser Dale Blahna 《Human ecology: an interdisciplinary journal》2013,41(5):651-665
Ecosystem-based planning and management have stimulated the need to gather sociocultural values and human uses of land in formats accessible to diverse planners and researchers. Human Ecology Mapping (HEM) approaches offer promising spatial data gathering and analytical tools, while also addressing important questions about human-landscape connections. This article reviews and compares the characteristics of three HEM approaches that are increasingly used in natural resource management contexts, each focused on a particular aspect of human-environmental interactions. These aspects include tenure and resource use (TRU), local ecological knowledge (LEK), and sense of place (SOP). We discuss their origins, provide examples of their use, and identify challenges to their application. Our review serves as a guide for environmental managers, planners, and communities interested in gathering spatial data on aspects of human ecology important in ecosystem-based management and planning, and for scientists designing socioecological research. 相似文献
93.
Daniela Josa Elaine F.F. da Cunha Teodorico C. Ramalho Thais C.S. Souza Melissa S. Caetano 《Journal of biomolecular structure & dynamics》2013,31(4):373-376
Abstract Rifamicyns (Rifs) are antibiotic widely used for the treatment of tuberculosis (TB); nevertheless, their efficacy has been limited by a high percentage of mutations, principally in the rpoB gene. In this work, the first three-dimensional molecular model of the hypothetical structures for the wild-type and D516V and H526L mutants of Mycobacterium tuberculosis (mtRNAP) were elucidated by a homology modeling method. In addition, the orientations and binding affinities of some Rifs with those new structures were investigated. Our findings could be helpful for the design of new more potent rifamycin analogs. 相似文献
94.
Melissa Adiatman Masayuki Ueno Mari Ohnuki Chiyoko Hakuta Kayoko Shinada Yoko Kawaguchi 《Gerodontology》2013,30(4):262-269
Gerodontology 2012; doi: 10.1111/j.1741‐2358.2012.00673.x Functional tooth units and nutritional status of older people in care homes in Indonesia Objectives: To investigate the relationship between functional tooth units (FTUs) and nutritional status. Methods: One hundred females (mean age: 72.4 ± 8.2 years) at four private care homes in Jakarta, Indonesia were interviewed and clinically examined. The oral examination included the assessment of teeth, prosthetic status, and number of FTUs. The total number of FTUs was further divided by tooth composition: natural tooth against natural tooth (NN‐FTUs), natural tooth against denture (ND‐FTUs), and denture against denture (DD‐FTUs). Nutritional status was evaluated using the body mass index (BMI) and the Mini Nutritional Assessment (MNA). Results: The mean numbers of teeth present, NN‐FTUs, ND‐FTUs, DD‐FTUs, and total FTUs were 13.1 ± 10.4, 1.7 ± 3.0, 1.2 ± 3.3, 0.4 ± 1.2 and 3.3 ± 4.4, respectively. The mean BMI and MNA scores were 24.8 ± 5.0 and 22.6 ± 2.8, respectively. Subjects with a normal BMI had a significantly higher total number of FTUs (3.6 ± 4.6) compared with underweight subjects (0.1 ± 0.3). Subjects with a normal MNA had a significantly higher number of NN‐FTU (2.6 ± 3.7) compared to those who were at risk or in a state of under‐nutrition (1.2 ± 2.4). Conclusion: This study revealed significant relationships between the number of FTUs and nutritional status. Keeping the posterior occlusion should be emphasized in order to maintain good nutritional status in older subjects. 相似文献
95.
Aims
Weed control in rice is challenging, particularly in light of increased resistance to herbicides in weed populations including Echinochloa crus-galli (L.) Beauv. Indica rice cultivars can produce high yields and suppress barnyardgrass, but have not been commercially acceptable in the U.S. due to inferior agronomic traits and grain quality. Our objectives were to combine high yield and weed-suppressive characteristics from indica cultivars with commercially acceptable grain quality and plant types from long-grain cultivars grown in the southern U.S.Methods
Crosses between indica and commercial tropical japonica (cv. Katy, and cv. Drew) rice were evaluated for weed suppression and agronomic traits in a breeding program.Results
In some tests, the selection STG06L-35-061 was nearly as weed suppressive as PI 312777, the suppressive parent, and more suppressive than its tropical japonica parents. Its main crop yield is commercially acceptable, and intermediate between PI 312777 and Katy. Its milling quality and cooking quality are similar to long-grain commercial cultivars, and it has resistance to rice blast disease. Marker analyses identified introgressions from the indica parents on chromosomes 1 and 3 of STG06L-35-061 that require further analysis as possible sources of weed suppressive traits.Conclusions
STG06L-35-061 might be suitable for organic rice or reduced input conventional systems. 相似文献96.
Multiple classes of cell surface receptors and ion channels participate in the detection of changes in environmental stimuli, and thereby influence animal behavior. Among the many classes of ion channels, Transient Receptor Potential (TRP) cation channels are notable in contributing to virtually every sensory modality, and in controlling a daunting array of behaviors. TRP channels appear to be conserved in all metazoan organisms including worms, insects and humans. Flies encode 13 TRPs, most of which are expressed and function in sensory neurons, and impact behaviors ranging from phototaxis to thermotaxis, gravitaxis, the avoidance of noxious tastants and smells and proprioception. Multiple diseases result from defects in TRPs, and flies provide an excellent animal model for dissecting the mechanisms underlying “TRPopathies.” Drosophila TRPs also function in the sensation of botanically derived insect repellents, and related TRPs in insect pests are potential targets for the development of improved repellents to combat insect-borne diseases. 相似文献
97.
Johanna V. Weiss Jeremy A. Rentz Todd Plaia Scott C. Neubauer Melissa Merrill-Floyd Tim Lilburn 《Geomicrobiology journal》2013,30(7-8):559-570
Iron deposits (Fe plaque) on wetland plant roots contain abundant microbial populations, including Fe(II)-oxidizing bacteria (FeOB) that have not been cultured previously. In this study, 4 strains of Fe plaque-associated FeOB were isolated from 4 species of wetland plants. All 4 isolates grew in tight association with Fe-oxides, but did not form any identifiable Fe-oxide structures. All strains were obligate lithotrophic Fe(II)-oxidizers that were microaerobic, and were unable to use other inorganic or organic energy sources. One strain, BrT, was shown to fix 14 CO 2 at a rate consistent with its requirement for total cell carbon. The doubling times for the strains varied between 9.5 and 15.8 hours. The fatty acid methyl ester (FAME) profiles of 2 strains, BrT and CCJ, revealed that 16:0, 15:1 isoG, and 14:0 were dominant fatty acids. Phylogenetic analysis of the 16S rRNA gene indicated that all the strains were Betaproteobacteria. Two of the strains, BrT and Br-1 belong to a new species, Sideroxydans paludicola; a third strain, LD-1, is related to Sideroxydans lithotrophicus, a recently described species of FeOB. The fourth isolate, Ferritrophicum radicicola, represented a new genus in a new order of Betaproteobacteria, the Ferritrophicales. There are no other cultured isolates in this order. A small subunit rRNA gene-based, cultivation-independent analysis of Typha latifolia collected from a wetland revealed terminal restriction fragment profiles (tRFLP) consistent with the presence of these bacteria in the rhizosphere. These novel organisms likely play an important role in Fe(II) oxidation kinetics and Fe cycling within many terrestrial and freshwater environments. 相似文献
98.
99.
Despina Soteriou Banu Iskender Adam Byron Jonathan D. Humphries Simon Borg-Bartolo Marie-Claire Haddock Melissa A. Baxter David Knight Martin J. Humphries Susan J. Kimber 《The Journal of biological chemistry》2013,288(26):18716-18731
Human embryonic stem cells (hESCs) are pluripotent cells that have indefinite replicative potential and the ability to differentiate into derivatives of all three germ layers. hESCs are conventionally grown on mitotically inactivated mouse embryonic fibroblasts (MEFs) or feeder cells of human origin. In addition, feeder-free culture systems can be used to support hESCs, in which the adhesive substrate plays a key role in the regulation of stem cell self-renewal or differentiation. Extracellular matrix (ECM) components define the microenvironment of the niche for many types of stem cells, but their role in the maintenance of hESCs remains poorly understood. We used a proteomic approach to characterize in detail the composition and interaction networks of ECMs that support the growth of self-renewing hESCs. Whereas many ECM components were produced by supportive and unsupportive MEF and human placental stromal fibroblast feeder cells, some proteins were only expressed in supportive ECM, suggestive of a role in the maintenance of pluripotency. We show that identified candidate molecules can support attachment and self-renewal of hESCs alone (fibrillin-1) or in combination with fibronectin (perlecan, fibulin-2), in the absence of feeder cells. Together, these data highlight the importance of specific ECM interactions in the regulation of hESC phenotype and provide a resource for future studies of hESC self-renewal. 相似文献
100.
Dan H. Barouch Kathryn E. Stephenson Erica N. Borducchi Kaitlin Smith Kelly Stanley Anna G. McNally Jinyan Liu Peter Abbink Lori F. Maxfield Michael S. Seaman Anne-Sophie Dugast Galit Alter Melissa Ferguson Wenjun Li Patricia L. Earl Bernard Moss Elena E. Giorgi James J. Szinger Leigh Anne Eller Erik A. Billings Mangala Rao Sodsai Tovanabutra Eric Sanders-Buell Mo Weijtens Maria G. Pau Hanneke Schuitemaker Merlin L. Robb Jerome H. Kim Bette T. Korber Nelson L. Michael 《Cell》2013