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101.
AS Glen D Anderson CJ Veltman PM Garvey M Nichols 《New Zealand journal of zoology.》2016,43(2):127-137
A major challenge in controlling overabundant wildlife is monitoring their populations, particularly as they decline to very low density. Camera traps and wildlife detector dogs are increasingly being used for this purpose. We compared the cost-effectiveness of these two approaches for detecting feral cats (Felis catus) on two pastoral properties in Hawke's Bay, North Island, New Zealand. One property was subject to intensive pest removal, while the other had no recent history of pest control. Camera traps and wildlife detector dogs detected cats at similar rates at both sites. The operating costs of each method were also comparable. We identify a number of advantages and disadvantages of each technique, and suggest priorities for further research. 相似文献
102.
CJ Cooksey 《Biotechnic & histochemistry》2017,92(2):134-140
The name, gentian, appeared about 1880. Immediately following its discovery in 1861, this violet dye was known as Violet de Paris or as methyl violet. Initially used as a textile dye, it was soon used to color virtually anything. The names and identity of the components, the varying modes of manufacture, analytical methods and the dye’s significant contribution to biological staining are discussed here. Finally, I discuss the dye’s declining medical use following the revelation of its toxic nature. 相似文献
103.
Thao P Phan Aubrey L Maryniak Christina A Boatwright Junsu Lee Alisa Atkins Andrea Tijhuis Diana CJ Spierings Hisham Bazzi Floris Foijer Philip W Jordan Travis H Stracker Andrew J Holland 《The EMBO journal》2021,40(1)
Mutations in centrosome genes deplete neural progenitor cells (NPCs) during brain development, causing microcephaly. While NPC attrition is linked to TP53‐mediated cell death in several microcephaly models, how TP53 is activated remains unclear. In cultured cells, mitotic delays resulting from centrosome loss prevent the growth of unfit daughter cells by activating a pathway involving 53BP1, USP28, and TP53, termed the mitotic surveillance pathway. Whether this pathway is active in the developing brain is unknown. Here, we show that the depletion of centrosome proteins in NPCs prolongs mitosis and increases TP53‐mediated apoptosis. Cell death after a delayed mitosis was rescued by inactivation of the mitotic surveillance pathway. Moreover, 53BP1 or USP28 deletion restored NPC proliferation and brain size without correcting the upstream centrosome defects or extended mitosis. By contrast, microcephaly caused by the loss of the non‐centrosomal protein SMC5 is also TP53‐dependent but is not rescued by loss of 53BP1 or USP28. Thus, we propose that mutations in centrosome genes cause microcephaly by delaying mitosis and pathologically activating the mitotic surveillance pathway in the developing brain. 相似文献
104.
Joris?J?Glas Juan?M?Alba Sauro?Simoni Carlos?A?Villarroel Marije?Stoops Bernardus?CJ?Schimmel Robert?C?Schuurink Maurice?W?Sabelis Merijn?R?KantEmail author 《BMC biology》2014,12(1):98
Background
Plants have inducible defenses to combat attacking organisms. Hence, some herbivores have adapted to suppress these defenses. Suppression of plant defenses has been shown to benefit herbivores by boosting their growth and reproductive performance.Results
We observed in field-grown tomatoes that spider mites (Tetranychus urticae) establish larger colonies on plants already infested with the tomato russet mite (Aculops lycopersici). Using laboratory assays, we observed that spider mites have a much higher reproductive performance on russet mite-infested plants, similar to their performance on the jasmonic acid (JA)-biosynthesis mutant def-1. Hence, we tested if russet mites suppress JA-responses thereby facilitating spider mites. We found that russet mites manipulate defenses: they induce those mediated by salicylic acid (SA) but suppress those mediated by JA which would otherwise hinder growth. This suppression of JA-defenses occurs downstream of JA-accumulation and is independent from its natural antagonist SA. In contrast, spider mites induced both JA- and SA-responses while plants infested with the two mite species together display strongly reduced JA-responses, yet a doubled SA-response. The spider mite-induced JA-response in the presence of russet mites was restored on transgenic tomatoes unable to accumulate SA (nahG), but russet mites alone still did not induce JA-responses on nahG plants. Thus, indirect facilitation of spider mites by russet mites depends on the antagonistic action of SA on JA while suppression of JA-defenses by russet mites does not. Furthermore, russet mite-induced SA-responses inhibited secondary infection by Pseudomonas syringae (Pst) while not affecting the mite itself. Finally, while facilitating spider mites, russet mites experience reduced population growth.Conclusions
Our results show that the benefits of suppressing plant defenses may diminish within communities with natural competitors. We show that suppression of defenses via the JA-SA antagonism can be a consequence, rather than the cause, of a primary suppression event and that its overall effect is determined by the presence of competing herbivores and the distinct palette of defenses these induce. Thus, whether or not host-defense manipulation improves an herbivore’s fitness depends on interactions with other herbivores via induced-host defenses, implicating bidirectional causation of community structure of herbivores sharing a plant.105.
A report of the ESF-EMBO Symposium Bacterial Networks (BacNet08), Sant Feliu de Guixols, Spain, 13-18 September 2008. 相似文献
106.
Isolated populations of drosophila pseudoobscura, separated from North
American populations by about 2,400 km, were found in Colombia in 1960. We
compared for sequences of the small ribosomal RNA (srRNA) gene on the
mitochondria between North American and Colombian D. pseudoobscura in order
to clarify the age of the Colombian isolates. The North American
populations were not genetically different from each other but were
genetically different from the Colombian populations. The Mexican strains
represent the area from which the Colombian founders might have come. The
estimated net nucleotide divergence between Mexican and Colombian D.
pseudoobscura indicates that the Colombian population is not an ancient
lineage. Phylogenies using both distance and parsimony methodologies
reinforced this conclusion. The Colombian samples group together with both
methods but, according to the bootstrap analysis, not significantly. It
appears that the populations have not been separated long enough for their
DNA sequences to show much divergence.
相似文献
107.
108.
Cees J. N. Buisman Willie Driessen Hans Meijer Gatze Lettinga 《Applied microbiology and biotechnology》1990,33(4):459-462
Summary Neither acetate nor higher fatty acids and glucose have a significant effect on the biotechnological process for sulphide removal at 20° C, in which sulphide is oxidized to sulphur using oxygen. The oxidation of acetate and propionate with oxygen is mainly dependent on the sulphide and oxygen concentrations in the reactor. The occurrence of Thiothrix filaments in sulphide-removing waste-water treatment systems has been investigated using a fixer-film upflow reactor. The influent of this reactor consisted of anaerobically treated paper-mill waste-water, with a sulphide concentration of 140 mg/1. It was found that sulphide loading rate is the decisive parameter as to whether or not Thiothrix will develop in a sulphide-removing reactor.
Offprint requests to: C. J. N. Buisman 相似文献
109.
Background
Many plant species show induced responses that protect them against exogenous attacks. These responses involve the production of many different bioactive compounds. Plant species belonging to the Brassicaceae family produce defensive glucosinolates, which may greatly influence their favorable nutritional properties for humans. Each responding compound may have its own dynamic profile and metabolic relationships with other compounds. The chemical background of the induced response is therefore highly complex and may therefore not reveal all the properties of the response in any single model. 相似文献110.