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41.
Ethnobotanical surveys were conducted to locate culturally important, regionally scarce, and disappearing medicinal plants
via a novel participatory methodology which involves healer-expert knowledge in interactive spatial modeling to prioritize
conservation efforts and thus facilitate health promotion via medicinal plant resource sustained availability. These surveys,
conducted in the Maya Mountains, Belize, generate ethnobotanical, ecological, and geospatial data on species which are used
by Q’eqchi’ Maya healers in practice. Several of these mountainous species are regionally scarce and the healers are expressing
difficulties in finding them for use in promotion of community health and wellness. Based on healers’ input, zones of highest
probability for locating regionally scarce, disappearing, and culturally important plants in their ecosystem niches can be
facilitated by interactive modeling. In the present study, this is begun by choosing three representative species to train
an interactive predictive model. Model accuracy was then assessed statistically by testing for independence between predicted
occurrence and actual occurrence of medicinal plants. A high level of accuracy was achieved using a small set of exemplar
data. This work demonstrates the potential of combining ethnobotany and botanical spatial information with indigenous ecosystems
concepts and Q’eqchi’ Maya healing knowledge via predictive modeling. Through this approach, we may identify regions where
species are located and accordingly promote for prioritization and application of in situ and ex situ conservation strategies
to protect them. This represents a significant step toward facilitating sustained culturally relative health promotion as
well as overall enhanced ecological integrity to the region and the earth. 相似文献
42.
Rangel-Castro JI Prosser JI Ostle N Scrimgeour CM Killham K Meharg AA 《Environmental microbiology》2005,7(4):544-552
The influence of liming on rhizosphere microbial biomass C and incorporation of root exudates was studied in the field by in situ pulse labelling of temperate grassland vegetation with (13)CO(2) for a 3-day period. In plots that had been limed (CaCO(3) amended) annually for 3 years, incorporation into shoots and roots was, respectively, greater and lower than in unlimed plots. Analysis of chloroform-labile C demonstrated lower levels of (13)C incorporation into microbial biomass in limed soils compared to unlimed soils. The turnover of the recently assimilated (13)C compounds was faster in microbial biomass from limed than that from unlimed soils, suggesting that liming increases incorporation by microbial communities of root exudates. An exponential decay model of (13)C in total microbial biomass in limed soils indicated that the half-life of the tracer within this carbon pool was 4.7 days. Results are presented and discussed in relation to the absolute values of (13)C fixed and allocated within the plant-soil system. 相似文献
43.
The major psychotic illnesses, schizophrenia and bipolar disorder (BD), are among the most heritable common disorders, but
finding specific susceptibility genes for them has not been straightforward. The reasons are widely assumed to include lack
of valid phenotypic definition, absence of good theories of pathophysiology for candidate gene studies, and the involvement
of many genes, each making small contributions to population risk. Within the last year or so, a number of genome wide association
(GWAS) of schizophrenia and BD have been published. These have produced stronger evidence for association to specific risk
loci than have earlier studies, specifically for the zinc finger binding protein 804A (ZNF804A) locus in schizophrenia and for the calcium channel, voltage-dependent, L type, alpha 1C subunit (CACNA1C) and ankyrin 3, node of Ranvier (ANK3) loci in bipolar disorder. The ZNF804A and CACNA1C loci appear to influence risk for both disorders, a finding that supports the hypothesis that schizophrenia and BD are not
aetiologically distinct. In the case of schizophrenia, a number of rare copy number variants have also been detected that
have fairly large effect sizes on disease risk, and that additionally influence risk of autism, mental retardation, and other
neurodevelopmental disorders. The existing findings point to some likely pathophysiological mechanisms but also challenge
current concepts of disease classification. They also provide grounds for optimism that larger studies will reveal more about
the origins of these disorders, although currently, very little of the genetic risk of either disorder is explained. 相似文献
44.
Thomas Hedemark Lundhede Jette Bredahl Jacobsen Nick Hanley Jon Fjelds? Carsten Rahbek Niels Strange Bo Jellesmark Thorsen 《PloS one》2014,9(7)
There is increasing evidence that global climate change will alter the spatiotemporal occurrences and abundances of many species at continental scales. This will have implications for efficient conservation of biodiversity. We investigate if the general public in Denmark are willing to pay for the preservation of birds potentially immigrating and establishing breeding populations due to climate change to the same extent that they are for native species populations currently breeding in Denmark, but potentially emigrating due to climate change. We find that Danish citizens are willing to pay much more for the conservation of birds currently native to Denmark, than for bird species moving into the country – even when they are informed about the potential range shifts associated with climate change. The only exception is when immigrating species populations are under pressure at European level. Furthermore, people believing climate change to be man-made and people more knowledgeable about birds tended to have higher WTP for conservation of native species, relative to other people, whereas their preferences for conserving immigrant species generally resembled those of other people. Conservation investments rely heavily on public funding and hence on public support. Our results suggest that cross-country coordination of conservation efforts under climate change will be challenging in terms of achieving an appropriate balance between cost-effectiveness in adaptation and the concerns of a general public who seem mostly worried about protecting currently-native species. 相似文献
45.
Field D Garrity GM Sansone SA Sterk P Gray T Kyrpides N Hirschman L Glöckner FO Kottmann R Angiuoli S White O Dawyndt P Thomson N Gil IS Morrison N Tatusova T Mizrachi I Vaughan R Cochrane G Kagan L Murphy S Schriml L;Genomic Standards Consortium 《Omics : a journal of integrative biology》2008,12(2):109-113
46.
Douglas P Cui X Block WD Yu Y Gupta S Ding Q Ye R Morrice N Lees-Miller SP Meek K 《Molecular and cellular biology》2007,27(5):1581-1591
The protein kinase activity of the DNA-dependent protein kinase (DNA-PK) is required for the repair of DNA double-strand breaks (DSBs) via the process of nonhomologous end joining (NHEJ). However, to date, the only target shown to be functionally relevant for the enzymatic role of DNA-PK in NHEJ is the large catalytic subunit DNA-PKcs itself. In vitro, autophosphorylation of DNA-PKcs induces kinase inactivation and dissociation of DNA-PKcs from the DNA end-binding component Ku70/Ku80. Phosphorylation within the two previously identified clusters of phosphorylation sites does not mediate inactivation of the assembled complex and only partially regulates kinase disassembly, suggesting that additional autophosphorylation sites may be important for DNA-PK function. Here, we show that DNA-PKcs contains a highly conserved amino acid (threonine 3950) in a region similar to the activation loop or t-loop found in the protein kinase domain of members of the typical eukaryotic protein kinase family. We demonstrate that threonine 3950 is an in vitro autophosphorylation site and that this residue, as well as other previously identified sites in the ABCDE cluster, is phosphorylated in vivo in irradiated cells. Moreover, we show that mutation of threonine 3950 to the phosphomimic aspartic acid abrogates V(D)J recombination and leads to radiation sensitivity. Together, these data suggest that threonine 3950 is a functionally important, DNA damage-inducible phosphorylation site and that phosphorylation of this site regulates the activity of DNA-PKcs. 相似文献
47.
Luaine Bandounas Nick JP Wierckx Johannes H de Winde Harald J Ruijssenaars 《BMC biotechnology》2011,11(1):1-11
Background
The number of biotransformations that use nicotinamide recycling systems is exponentially growing. For this reason one of the current challenges in biocatalysis is to develop and optimize more simple and efficient cofactor recycling systems. One promising approach to regenerate NAD+ pools is the use of NADH-oxidases that reduce oxygen to hydrogen peroxide while oxidizing NADH to NAD+. This class of enzymes may be applied to asymmetric reduction of prochiral substrates in order to obtain enantiopure compounds.Results
The NADH-oxidase (NOX) presented here is a flavoenzyme which needs exogenous FAD or FMN to reach its maximum velocity. Interestingly, this enzyme is 6-fold hyperactivated by incubation at high temperatures (80°C) under limiting concentrations of flavin cofactor, a change that remains stable even at low temperatures (37°C). The hyperactivated form presented a high specific activity (37.5 U/mg) at low temperatures despite isolation from a thermophile source. Immobilization of NOX onto agarose activated with glyoxyl groups yielded the most stable enzyme preparation (6-fold more stable than the hyperactivated soluble enzyme). The immobilized derivative was able to be reactivated under physiological conditions after inactivation by high solvent concentrations. The inactivation/reactivation cycle could be repeated at least three times, recovering full NOX activity in all cases after the reactivation step. This immobilized catalyst is presented as a recycling partner for a thermophile alcohol dehydrogenase in order to perform the kinetic resolution secondary alcohols.Conclusion
We have designed, developed and characterized a heterogeneous and robust biocatalyst which has been used as recycling partner in the kinetic resolution of rac-1-phenylethanol. The high stability along with its capability to be reactivated makes this biocatalyst highly re-useable for cofactor recycling in redox biotransformations. 相似文献48.
The efficiency and effectiveness of different sea urchin removal methods for kelp forest restoration
Sea urchin overgrazing has caused widespread phase shifts from kelp forests to “urchin barrens” on many temperate reefs, reducing habitat complexity, productivity, and biodiversity. Sea urchin removal is increasingly used for kelp restoration; however, few studies have quantified the efficiency and effectiveness of different removal methods, resulting in limited understanding of their practicality. In this study, the efficiency (removal rate) and effectiveness (proportion removed) of four removal methods were evaluated in northeastern New Zealand. We compared culling or collecting sea urchins by either SCUBA or freediving in 128 small-scale plots (25 m2). We also evaluated the efficiency and effectiveness of culling in four large (1.6–2 ha) barren areas, scales relevant for restoration. On average, culling sea urchins was 1.9–4.4 times faster than collecting, and SCUBA was 1.5–3.3 times faster than freediving. Removal rates increased with sea urchin density, especially for culling on SCUBA, while freediving removal rates increased with experience. Effectiveness was lower in large-scale removals (86–93% of sea urchins ≥40 mm removed) compared to small-scale removals (98–99%), but sufficient for restoration objectives. Estimated time per area (using SCUBA culling) was similar across large-scale removals (49–57 hours/ha), despite an almost 2-fold variation in initial sea urchin densities (approximately 4–8 urchins/m2), suggesting area may better predict total removal time than simply number of sea urchins across low-density ranges. While sea urchin removal provides a rapid, feasible, and effective approach to restoring kelp in urchin barrens, restoration plans need to also address the causes of sea urchin overpopulation to ensure long-term benefits. 相似文献
49.
50.
Roland F. Schwarz Anne Trinh Botond Sipos James D. Brenton Nick Goldman Florian Markowetz 《PLoS computational biology》2014,10(4)
Intra-tumour genetic heterogeneity is the result of ongoing evolutionary change within each cancer. The expansion of genetically distinct sub-clonal populations may explain the emergence of drug resistance, and if so, would have prognostic and predictive utility. However, methods for objectively quantifying tumour heterogeneity have been missing and are particularly difficult to establish in cancers where predominant copy number variation prevents accurate phylogenetic reconstruction owing to horizontal dependencies caused by long and cascading genomic rearrangements. To address these challenges, we present MEDICC, a method for phylogenetic reconstruction and heterogeneity quantification based on a Minimum Event Distance for Intra-tumour Copy-number Comparisons. Using a transducer-based pairwise comparison function, we determine optimal phasing of major and minor alleles, as well as evolutionary distances between samples, and are able to reconstruct ancestral genomes. Rigorous simulations and an extensive clinical study show the power of our method, which outperforms state-of-the-art competitors in reconstruction accuracy, and additionally allows unbiased numerical quantification of tumour heterogeneity. Accurate quantification and evolutionary inference are essential to understand the functional consequences of tumour heterogeneity. The MEDICC algorithms are independent of the experimental techniques used and are applicable to both next-generation sequencing and array CGH data. 相似文献