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61.
Summary The impact of water diversion on fish populations is a global issue. Many countries have invested substantial funding into research and implementation strategies to ensure fish are protected at diversions that take water out of rivers for agriculture and other human uses. The most common management action is the installation of fish screens, and a wide range of designs are presently available that suit a large range of diversions. The Murray–Darling Basin is the largest catchment in Australia and has been substantially developed over the past 100 years to store and divert water for that protect fish from escaping into the irrigation systems. Recent studies have determined that water diversions have substantial impacts on native fish populations, but there are presently no coordinated efforts for mitigation strategies. The purpose of this review is to highlight aspects of successful screening programmes worldwide and identify those that could be directly applied to the Murray–Darling Basin. The development of similar programmes in the United States, New Zealand and the United Kingdom has identified that sufficient information and technology exists to inform the development of fish screening programmes. There is no need to commence implementation from first principles, and substantial progress can be achieved by applying successful aspects of other programmes. By identifying existing designs, defining ecological targets, developing generalised guidelines appropriate for local conditions and engaging the community, a co‐ordinated and successful fish screening programme could be directly applied to the Murray–Darling Basin. This would have substantial benefits for the long‐term sustainability of native fish without compromising water supply requirements. 相似文献
62.
KM Verspoor KB Cohen A Lanfranchi C Warner HL Johnson C Roeder JD Choi C Funk Y Malenkiy M Eckert N Xue WA Baumgartner M Bada M Palmer LE Hunter 《BMC bioinformatics》2012,13(1):207-26
ABSTRACT: BACKGROUND: We introduce the linguistic annotation of a corpus of 97 full-text biomedical publications, known as the Colorado Richly Annotated Full Text (CRAFT) corpus. We further assess the performance of existing tools for performing sentence splitting, tokenization, syntactic parsing, and named entity recognition on this corpus. RESULTS: Many biomedical natural language processing systems demonstrated large differences between their previously published results and their performance on the CRAFT corpus when tested with the publicly available models or rule sets. Trainable systems differed widely with respect to their ability to build high-performing models based on this data. CONCLUSIONS: The finding that some systems were able to train high-performing models based on this corpus is additional evidence, beyond high inter-annotator agreement, that the quality of the CRAFT corpus is high. The overall poor performance of various systems indicates that considerable work needs to be done to enable natural language processing systems to work well when the input is full-text journal articles. The CRAFT corpus provides avaluable resource to the biomedical natural language processing community for evaluation and training of new models for biomedical full text publications. 相似文献
63.
Micromechanics of smooth adhesive organs in stick insects: pads are mechanically anisotropic and softer towards the adhesive surface 总被引:1,自引:0,他引:1
Ingo Scholz Werner Baumgartner Walter Federle 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2008,194(4):373-384
Animals have evolved adhesive structures on their legs to cling to the substrate during locomotion. Here we characterise the
ultrastructure and mechanical properties of adhesive pads in Carausius morosus (Phasmatodea) using atomic force microscopy (AFM) as well as transmission and scanning electron microscopy (TEM, SEM). The
smooth adhesive arolium has a soft cuticle consisting of principal rods, which branch into finer fibres near the surface.
Indentation experiments showed that the pad material consists of distinct layers with different mechanical properties. The
100–300 nm thick outermost layer consisting of the cuticulin envelope and the epicuticle is extremely soft and resilient (mean
effective Young’s modulus 12 kPa), while the subjacent procuticle is a much stiffer material (mean effective Young’s modulus
625 kPa). AFM contact mode imaging revealed that the cuticle is mechanically anisotropic, which can be explained by its fibrillar
inner structure. We propose that the described layered structure of smooth adhesive pads, consisting of materials decreasing
in stiffness towards the outer surface, represents a superior design to conform and adhere to substrates with roughnesses
at different length scales. This design principle could be easily implemented in technical adhesives, and thus has a potential
to inspire biomimetic applications. 相似文献
64.
Pichler H Baumgartner S Freudenschuss M Palme S Binder EM Krska R 《Mycotoxin Research》2001,17(2):202-205
Enzyme-linked immunosorbent assays (ELISA) proved to be a fast and simple method for the detection of mycotoxins and other undesired contaminants in food and feed. The present study is focused on the optimisation and exploitation of the egg yolk antibody technology in order to develop competitive ELISAs for the detection of mycotoxins in cereals. Due to its importance as one of the most relevant Fusarium mycotoxins, the trichothecene deoxynivalenol (DON) was selected as representative. Chickens were immunised with different protein conjugates performing varying booster intervals. The antibodies were isolated by the poly(ethylene glycol) precipitation method according to Polson. By use of these antibodies an indirect competitive ELISA was developed for the detection of DON. First investigations of naturally contaminated wheat samples showed a good correspondence with results obtained by GC-ECD when calibration in blank wheat extracts was performed. 相似文献
65.
66.
Marc Stadler Manuela Baumgartner Klaus Ide Andreas Popp Hartmund Wollweber 《Mycological Progress》2002,1(1):31-42
Representative specimens of fifteen Daldinia spp. were studied for ultrastructural characteristics of their ascospores by scanning electron microscopy (SEM). The ornamentation
of their outermost spore layers was found to be species-consistent, confirming the results of concurrent studies on the morphology
of their teleomorphs and anamorphs, secondary metabolite profiles and PCR-based genetic fingerprints. Daldinia spp. may either show smooth or transversally striated ascospores. The spores of the species within the latter group are always
ellipsoid-equilateral to ellipsoid-inequilateral with narrowly rounded ends. Smooth, broadly ellipsoid to cylindrical ascospores
were observed in all species (D. caldariorum, D. fissa and D. loculata) that are known to produce their stromata on substrates damaged by fire. The ascospores of D. concentrica differed from those of D. childiae (i.e., the cosmopolitan taxon previously regarded as D. concentrica ss. auct.) and other Daldinia spp. in showing a very faint ornamentation, which only became visible at 10000× magnification by SEM. A specimen collected
on the isle of Jersey (Channel Islands, UK) showed morphological similarities to the pantropical D. eschscholzii, but its ascospores appeared smooth by SEM, and it may therefore represent a previously undescribed species.
Dedicated to Professor Yoshinori Asakawa, Tokushima, Japan, on the occasion of his 60th birthday
PH-R Life Science Center Natural Products 相似文献
67.
Shawn G Dunkirk Mark A Wallert Matt L Baumgartner Joseph J Provost 《Protein expression and purification》2002,24(1):1-12
A 66-kDa molecular weight protein with phospholipase D activity was solubilized and partially purified from rat liver plasma membrane. The activity and regulation of this phospholipase D have been characterized. Immunoblot analyses indicated that the enzyme was distinct from hPLD1 and PLD2, but was recognized by an antibody to the 12 terminal amino acids of PLD1. PLD activity was stimulated by 1-100 microM Ca(2+) and Mg(2+) and displayed a pH optimum of 7.5. Activity was inhibited by both saturated and unsaturated fatty acids. This PLD was activated in an ATP-independent manner by the PKC isozymes alpha and betaII but not activated by other PKC isozymes. It was also stimulated by the small G-proteins RhoA and ARF. RhoA stimulated the greatest activation, followed by ARF and PKC(alpha). This enzyme was further activated in a synergistic manner when combinations of PKC(alpha) and RhoA or ARF were used. This enzyme displayed a greater response activation by RhoA than to activation by ARF. While a potential breakdown product of PLD1, activation by RhoA indicates that the PLD characterized here is distinct from the other PLDs cloned or isolated to date. 相似文献
68.
Conrad J. Baumgartner 《The Western journal of medicine》1950,73(6):466-472
The embryonic origin of lateral cysts and fistulas remains controversial. They are, however, located in the general anatomic pattern of the embryonic thymic duct, which starts in the lateral pharyngeal wall and passes under the sternomastoid muscle to enter the mediastinum. The cyst is a unilocular, semiattached, non-translucent mass which has a tendency to become infected in 30 per cent of cases.The preauricular sinus occurs in front of the ear and is due either to a branchial cleft or an inclusion of one of the six primitive buds which form the external ear.Cystic hygroma is due to sequestrated lymphatic channels. These are always multilocular and rather invasive and may extend into mediastinum and arms.Diagnosis and treatment are considered in this presentation. 相似文献
69.
Diet and feeding habits of predatory fishes upstream and downstream of a low-level weir 总被引:2,自引:0,他引:2
L. J. Baumgartner 《Journal of fish biology》2007,70(3):879-894
A study investigating the influence of a low-level weir on the diets of three migratory percithyid species was undertaken on the Murrumbidgee River, Australia. A combination of fish community sampling and stomach flushing determined that Yanco Weir substantially impacted upon the abundance and feeding habits of golden perch Macquaria ambigua , Murray cod Maccullochella peelii peelii and trout cod Maccullochella macquariensis . The relative abundance of all three species was significantly greater downstream of the weir, where individuals attempting upstream migrations were obstructed. In areas of fish aggregations, some species displayed altered feeding strategies and exploited different prey taxa upstream and downstream of the weir. Diet overlap, and the proportion of individuals with empty stomachs, was also substantially greater from downstream zones. These results suggest that competition among species may be greater in areas of increased predator abundance and some species could be partitioning resources to minimize competitive interactions. Reducing accumulations of predatory species, by providing suitable fish passage facilities, would be an effective means to prevent such trophic interactions occurring at other low-level weirs. 相似文献
70.