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121.
Laparoscopic appendectomy to remove a metallic foreign body in a wild Bornean orangutan (Pongo pygmaeus) undergoing rehabilitation
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Karmele Llano Sanchez Ayu B. Handayani Christine L. Nelson Jaclyn W.L. Eng Wendi Prameswari Nigel Hicks Romain Pizzi 《Journal of medical primatology》2016,45(6):327-329
A laparoscopic appendectomy was performed in a wild orangutan (Pongo pygmaeus) undergoing rehabilitation, for a metal nail found on radiographs, using 3‐mm instrumentation. Post‐operative healing was rapid and uneventful, with return to the forest within 10 days. This is the first report of minimally invasive surgery in a wild orangutan. 相似文献
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Biodegradability of Vegetation-Derived Dissolved Organic Carbon in a Cool Temperate Ombrotrophic Bog
Andrew J. Pinsonneault Tim R. Moore Nigel T. Roulet Jean-François Lapierre 《Ecosystems》2016,19(6):1023-1036
Dissolved organic carbon (DOC) plays a key role in the peatland carbon balance and serves numerous ecological and chemical functions including acting as a microbial substrate. In this study, we quantify the concentration, biodegradability, and intrinsic properties of DOC obtained from peat, fresh material, and litter from nine species of ombrotrophic bog vegetation. Potential biodegradability was assessed by incubating vegetation extracts for 28 days in the dark and measuring percent DOC loss as the fraction of biodegradable DOC (%BDOC) while DOC properties were characterized using UV–Vis absorbance and fluorescence measurements. The mean initial DOC concentration extracted differed significantly among species (P < 0.05) and was significantly higher in fresh material, 217 ± 259 mg DOC l?1, than either litter or peat extracts with mean concentrations of 82.1 ± 117 mg DOC l?1 and 12.7 ± 1.0 mg DOC l?1, respectively (P < 0.05). %BDOC also differed significantly among species (P < 0.05) and ranged from 52 to 73% in fresh cuttings with the greatest fraction observed in S. magellanicum; 22–46% in litter; and 24% in peat. The majority of variability (82.5%) in BDOC was explained by initial absorbance at 254 nm and total dissolved nitrogen concentration which was further resolved into significant non-linear relationships between %BDOC and both humic-like and protein-like DOC fractions (P < 0.05). Our results highlight the extremely heterogeneous nature of the surface vegetation-derived DOC input in peatlands and stress the importance of vegetation species in peatland ecosystem function. 相似文献
124.
Occurrence of 16SrIV Subgroup A Phytoplasmas in Roystonea regia and Acrocomia mexicana Palms with Lethal Yellowing‐like Syndromes in Yucatán,Mexico
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María Narvaez Iván Córdova‐Lara Celso Reyes‐Martínez Carlos Puch‐Hau Luis Mota‐Narvaez Ana Collí Goretti Caamal Nigel Harrison Luis Sáenz Carlos Oropeza 《Journal of Phytopathology》2016,164(11-12):1111-1115
The lethal yellowing (LY) disease and LY‐type syndromes affecting several palm species are associated with 16SrIV phytoplasmas in the Americas. In Mexico, palms of the species Roystonea regia and the native Acrocomia mexicana were found to exhibit LY‐type symptoms, including leaf decay, starting with mature leaves, necrosis and atrophy of inflorescences. DNA extracts obtained from these palms could be amplified by nested‐PCR using phytoplasma‐universal primer pair P1/P7 followed by LY‐group‐specific primer pair LY16Sr/LY16Sf. Blast analysis of the sequences obtained revealed an identity of 100% for R. regia and 99.27% for A. mexicana with 16SrIV‐A strain associated with LY in Florida, USA (Acc. AF498309 ). Computer‐simulated RFLP analysis showed that the patterns for the phytoplasma DNA of the two palm species were highly similar to that for 16SrIV subgroup A strain. A neighbour‐joining tree was constructed, and the sequences of the two palm species clustered in the same clade of group 16SrIV subgroup A. The results therefore support that LY‐type syndromes observed in palms of R. regia and A. mexicana in the Yucatan region of Mexico are associated with 16SrIV subgroup A phytoplasmas. 相似文献
125.
Gangadharan Nishanthi Turner Richard Field Ray Oliver Stephen G. Slater Nigel Dikicioglu Duygu 《Bioprocess and biosystems engineering》2019,42(9):1399-1408
Bioprocess and Biosystems Engineering - There is a growing interest in mining and handling of big data, which has been rapidly accumulating in the repositories of bioprocess industries.... 相似文献
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Erica H. Odell Nigel E. Stork Roger L. Kitching 《Biological reviews of the Cambridge Philosophical Society》2019,94(4):1416-1429
Woody climbers or, ‘lianas’, are one of the features that characterise rainforests. They contribute substantially to plant diversity and leaf biomass which makes them a potentially important food source for herbivores. Here, we focus on insect herbivores, folivores in particular, to show how disparities in the quantitative and qualitative availability of leaves between lianas and trees may differentially influence insect folivory and the herbivore communities themselves. We develop a conceptual model and show that lianas in general have lower structural and chemical defences, a greater nutritional profile and a preferable phenology in comparison with trees, which, contrary to our expectations, has led to assemblages of more‐specialised insects. The impacts this has on higher trophic levels and broader ecological networks, however, are poorly known. We show through a study of four tropical floras from different biogeographic realms that lianas are likely to be a target for a wide range of insect herbivore taxa as they are a phylogenetically diverse group and increase diversity of higher taxa at local scales. This, in combination with their highly palatable leaves, may also make them a suitable temporary food source for insects during times when preferred host plants are scarce. This phenomenon has been observed in mammalian herbivores but awaits investigation in insects as does the effects this may have on survival and fitness. Apparent recent increases in liana abundances in some forests, likely due to climate change, makes understanding their role in supporting and maintaining biodiversity an increasingly important and necessary challenge. Since trees or saplings have usually been the subject of studies on insect herbivory, major knowledge gaps remain about the ways in which lianas contribute to, support and maintain the ecosystems in which they exist. We use our conceptual model to guide future research directions and express the necessity for caution when extrapolating explanations of herbivory derived from data on trees to growth forms with fundamentally different ecologies. 相似文献
128.
The refolding of recombinant protein from inclusion bodies expressed in Escherichia coli can present a process bottleneck. Yields at industrially relevant concentrations are restricted by aggregation of protein upon dilution of the denatured form. This article studies the effect of five factors upon the dilution refolding of protein in a twin impeller fed-batch system using refold buffer containing only the oxidized form of the redox reagent. Such a buffer is easier to prepare and more stable than a buffer containing both reduced and oxidized forms. The five factors chosen were: bulk impeller Reynolds number, mini-impeller Reynolds number, injection rate of denatured protein, redox ratio, and guanidine hydrochloride (GdHCl) concentration. A 2(5) factorial experiment was conducted at an industrially relevant protein concentration using lysozyme as the test system. The study identified that in the system used, the guanidine hydrochloride concentration, redox ratio, and injection rate were the most important factors in determining refolding yields. Two interactions were found to be important: redox ratio/guanidine hydrochloride concentration and guanidine hydrochloride concentration/injection rate. Conditions were also found at which high refolding yields could be achieved even with rapid injection and poor mixing efficiency. Therefore, a comparative assessment was carried out with minimal mixing in a simple batch-refolding mode of operation, which revealed different behavior to that of fed-batch. A graphical (windows of operation) analysis of the batch data suggested that optimal yields and productivity are obtained at high guanidine hydrochloride concentrations (1.2 M) and redox ratios of unity or greater. 相似文献
129.
Hey S Mayerhofer H Halford NG Dickinson JR 《The Journal of biological chemistry》2007,282(14):10472-10479
Sucrose nonfermenting-1 (Snf1)-related protein kinase-1 (SnRK1) of plants is a global regulator of carbon metabolism through the modulation of enzyme activity and gene expression. It is structurally and functionally related to the yeast protein kinase, Snf1, and to mammalian AMP-activated protein kinase. Two DNA sequences from Arabidopsis thaliana, previously known only by their data base accession numbers of NM_ 125448.3 (protein ID NP_200863) and NM_114393.3 (protein ID NP_566876) each functionally complemented a Saccharomyces cerevisiae elm1 sak1 tos3 triple mutant. This indicates that the Arabidopsis proteins are able to substitute for one of the missing yeast upstream kinases, which are required for activity of Snf1. Both plant proteins were shown to phosphorylate a peptide with the amino acid sequence of the phosphorylation site in the T-loop of SnRK1 and by inference SnRK1 in Arabidopsis. The proteins encoded by NM_125448.3 and NM_114393.3 have been named AtSnAK1 and AtSnAK2 (Arabidopsis thaliana SnRK1-activating kinase), respectively. We believe this is the first time that upstream activators of SnRK1 have been described in any plant species. 相似文献
130.
Competition for pollination is thought to be an important factor structuring flowering in many plant communities, particularly
among plant taxa with morphologically similar and easily accessible flowers. We examined the potential for heterospecific
pollen transfer (HPT) in a community of four Acacia species in a highly seasonal tropical habitat in Mexico. Partitioning of pollen flow among sympatric species appears to be
achieved, in part, through segregation of flowering in seasonal time, and interspecific differences in pollinator guilds.
However, two coflowering species (Acacia macracantha and Acacia angustissima) shared multiple flower visitors, raising the possibility of HPT. Each of these coflowering species showed high intraspecific
daily synchrony in pollen release, but dehisce at different times of day. Pollinators rapidly harvested available pollen from
one species before abandoning it to visit the flowers of the second later in the day. The activity of shared pollinators,
predominantly bees, is thus structured throughout the day, and potential for HPT reduced. Suggestive evidence in favour of
a resource partitioning explanation for this pattern is provided by the fact that A. macracantha showed significantly greater intraspecific synchrony when coflowering with a potential competitor (A. angustissima) than when flowering alone. We discuss our results in light of previous work on coflowering acacia assemblages in Tanzania
and Australia.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
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Nigel E. RaineEmail: |