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21.
Lin Schwarzkopf Paul Roe Paul G. Mcdonald David M. Watson Richard A. Fuller Slade Allen-Ankins 《Austral ecology》2023,48(7):1230-1237
Observatories are designed to collect data for a range of uses. The Australian Acoustic Observatory (A2O) was established to collect environmental sound, including audible species calls, from 344 recorders at 86 sites around Australia. We examine the potential of the A2O to monitor near threatened, threatened, endangered and critically endangered species, based on their vocal behaviour, geographic distributions in relation to the sites of the A2O and on some knowledge of habitat use. Using IUCN and EPBC lists of threatened and endangered species, we extracted species that vocalized in the audible range, and using conservative estimates of their geographic ranges, determined whether there was a possibility of hearing them at these sites. We found that it may be possible to detect up to 171 threatened species at sites established for the A2O, and that individual sites have the potential to detect up to 40 threatened species. All 86 sites occurred in locations where threatened species could possibly be detected, and the list of detectable species included birds, amphibians, and mammals. We have incidentally detected one mammal and four bird species in the data during other work. Threatening processes to which potentially detectable species were exposed included all but two IUCN threat categories. We concluded that with applications of technology to search the audio data from the A2O, it could serve as an important tool for monitoring threatened species. 相似文献
22.
Significant advances have recently been made in a number of areas concerning central nervous system (CNS) neoplasia. Particularly salient are the following: (1) gene amplification is related to increasing grade of human glioma malignancy and occurs in approximately 40% of the most common and most malignant variety of glioma, glioblastoma multiforme (GBM), (2) by far the most commonly amplified gene in glioblastomas is the epidermal growth factor receptor (EGFR) gene, which is amplified in about one third of GBMs, (3) a small percentage of GBMs amplify N-myc or the novel sequence gli, (4) the EGFR gene is rearranged in at least half of gliomas in which it is amplified, and (5) EGFR gene rearrangement results in external domain deletions that yield truncated EGF receptors. Antibodies specific for the mutant EGF receptor fusion junction have been successfully produced and provide stimulating new potential avenues for tumor imaging and therapy. For pediatric CNS neoplasms, only medulloblastoma has been investigated in adequate numbers; a small percentage exhibit amplification of either the N-myc or c-myc genes. 相似文献
23.
D. E. Chamberlain A. Joys P. J. Johnson L. Norton R. E. Feber R. J. Fuller 《Biology letters》2010,6(1):82-84
The generally higher biodiversity on organic farms may be influenced by management features such as no synthetic pesticide and fertilizer inputs and/or by differences in uncropped habitat at the site and landscape scale. We analysed bird and habitat data collected on 48 paired organic and conventional farms over two winters to determine the extent to which broad-scale habitat differences between systems could explain overall differences in farmland bird abundance. Density was significantly higher on organic farms for six out of 16 species, and none on conventional. Total abundance of all species combined was higher on organic farms in both years. Analyses using an information-theoretic approach suggested that both habitat extent and farm type were important predictors only for starling and greenfinch. Organic farming as currently practised may not provide significant benefits to those bird species that are limited by winter food resources, in particular, several declining granivores. 相似文献
24.
Benthic ctenophores (Platyctenida: Coeloplanidae) in south Florida: environmental conditions,habitats, abundances,and behaviors 下载免费PDF全文
Peter W. Glynn Brian Coffman Michael P. C. Fuller Shannon G. Moorhead Megan K. Williams Karim D. Primov Tayla N. Fortson Rachel N. Barrales Peter J. Glynn 《Invertebrate Biology》2017,136(4):379-393
Two benthic ctenophores, Coeloplana waltoni and Vallicula multiformis, are contrasted in terms of their coastal environments, habitats, abundances, seasonal occurrences, and behavior in south Florida. Coeloplana waltoni occurs as an epibiont on octocorals in open water settings, and V. multiformis is present in bio‐fouling communities, associated with macroalgae, bryozoans, and inanimate substrates in protected, back‐water habitats. In our study, individuals of C. waltoni were found under moderate to strong current flow and relatively constant temperature and salinity (T/S) conditions, whereas individuals of V. multiformis occurred at sites of low current flow and more variable T/S conditions. In C. waltoni, individuals generally adhered tightly to host colony surfaces, whereas in V. multiformis, individuals often disassociated from substrates and floated free. Mean population densities of C. waltoni ranged ~500–850 individuals 100 mL?1 (measured as the displacement volume of the octocoral habitat), and densities of V. multiformis ranged 5–360 individuals 100 mL?1 (measured as the displacement volume of the biofouling habitat). Abundance of C. waltoni was significantly highest in the 2014 warm season (June–October) when numerous minute (≤0.5 mm body length) juveniles were present. Vallicula multiformis was abundant in the 2015 and 2016 warm seasons (July–October), and also relatively abundant in the 2016 cool season (March–April). Ctenophore abundance and surface seawater temperature indicate a significant positive response to warm‐season conditions in C. waltoni, whereas numbers of V. multiformis did not show any effect of seawater temperature. Recently settled individuals of V. multiformis (≤1.0 mm) occurred throughout the year. Individuals of V. multiformis recruited to fiber‐coated sponges during warm and cool periods, with mean body sizes increasing in one cohort from 1.41 to 6.46 mm over a 39‐d period, suggesting a growth rate of ~4% d?1. Feeding in both species involves tentacle capture of water‐borne zooplankton and particulate organic matter. Individuals of C. waltoni were also observed inserting tentacles into octocoral polyps, possibly pilfering food. Chlorophyll a was detected in extracts of both ctenophore species. The high abundances and feeding behavior of benthic ctenophores could have a strong influence on octocoral and biofouling communities. 相似文献
25.
An uptake system on the serotonin neuronal membrane apparently functions to inactivate serotonin that has been released into the synaptic cleft. Various inhibitors of this active transport system on serotonin neurons are known, and some are specific in the sense that they do not inhibit the active uptake system on norepinephrine neurons. The most widely studied specific inhibitor of the serotonin neuron pump is fluoxetine, 3-(p-trifluoromethylphenoxy-N-methyl-3-phenyl propylamine (Lilly 110140). When fluoxetine or other effective but less specific serotonin uptake inhibitors are given, a rapid decrease in serotonin turnover occurs and the rate of firing of single neural units in the serotonin rich raphe area of brain is reduced. This decrease in serotonin turnover and release may be a compensatroy mechanism in response to an enhanced action of serotonin on synaptic receptors. Through the use of fluoxetine and other serotonin uptake inhibitors, the role of serotonin neurons in various brain functions--behavior, sleep, regulation of pituitary hormone release, thermoregulation, pain responsiveness, and so on--can be studied. 相似文献
26.
INVESTIGATION OF SECONDARY STRUCTURES AND MACROMOLECULAR INTERACTIONS IN BACTERIOPHAGE P22 BY LASER RAMAN SPECTROSCOPY 下载免费PDF全文
S. R. Fish K. A. Hartman M. T. Fuller Jonathan King G. J. Thomas Jr. 《Biophysical journal》1980,32(1):234-237
Laser Raman spectra of the DNA bacteriophage P22 and of its precursor particles and related structures have been obtained using 514.5-nm excitation. The spectra show that P22 DNA exists in the B form both inside of the phage head and after extraction from the phage. The major coat protein (gp5) contains a secondary structure composed of 18% α-helix, 20% β-sheet and 62% irregular conformations. The scaffolding protein (gp8) in the phage prohead is substantially richer than gp5 in α-helical content. Among the amino acid residues which give prominent Raman lines, the spectra show that tryptophans are exposed to solvent and most tyrosines are hydrogen bonded to positive donor groups. The above features of phage DNA and protein structures are nearly invariant to changes in temperature up to 80°C, indicating a remarkable thermal stability of the phage head and its encapsulated DNA. 相似文献
27.
28.
Somatostatin gene expression in the thymus gland 总被引:8,自引:0,他引:8
A complex pattern of interactions appears to exist between the immune and neuroendocrine systems. Recently, vasopressin, oxytocin and vasoactive intestinal peptide have been isolated from the thymus. Using a rat somatostatin antisense RNA probe we have demonstrated expression of the somatostatin gene in the rat thymus. Furthermore, we have shown that the levels of thymic somatostatin mRNA exhibit a bell-shaped response to dexamethasone administration. Lipocortin I and II antisense RNA probes have been used as a positive control for the effects of the dexamethasone. We would suggest that somatostatin acts in the thymus in a paracrine mode to modulate T lymphocyte development. 相似文献
29.
Central and peripheral catecholamine depletion by 1-methyl-4-phenyl-tetrahydropyridine (MPTP) in rodents 总被引:1,自引:0,他引:1
1-Methyl-4-phenyl-tetrahydropyridine (MPTP) given in single doses to rats depleted norepinephrine concentration in heart and mesenteric artery but had little effect on catecholamine concentration in brain. MPTP did not share with amphetamine the ability to cause persistent depletion of striatal dopamine in iprindole-treated rats. Administration of MPTP via osmotic minipumps implanted s.c. for 24 hrs after a loading dose of MPTP in rats resulted in depletion of striatal dopamine and its metabolites one week later. MPTP in vitro was a reasonably potent, competitive and reversible inhibitor of MAO-A (monoamine oxidase type A). MPTP appeared to inhibit MAO-A in rat brain in vivo as determined by its antagonism of the inactivation of MAO-A by pargyline and by its antagonism of the increase in dopamine metabolites resulting from the administration of Ro 4-1284, a dopamine releaser. The inhibition of MAO-B by MPTP in vitro was noncompetitive, time-dependent, and not fully reversed by dialysis, consistent with the findings of others that MPTP is acted upon by MAO-B. In mice, four successive daily doses of MPTP is acted upon by MAO-B. In mice, four successive daily doses of MPTP given s.c. resulted in marked depletion of dopamine and its metabolites one week later, and the depletion of dopamine was completely prevented by pretreatment with deprenyl, which inhibited MAO-B but not MAO-A. These and other studies in rodents may help in elucidating the mechanisms involved in the destructive effects of MPTP on striatal dopamine neurons that lead to symptoms of Parkinson's disease in humans and in monkeys. 相似文献
30.
Identification of a QTL decreasing yield in barley linked to Mlo powdery mildew resistance 总被引:5,自引:0,他引:5
Thomas W.T.B. Baird E. Fuller J.D. Lawrence P. Young G.R. Russell J. Ramsay L. Waugh R. Powell W. 《Molecular breeding : new strategies in plant improvement》1998,4(5):381-393
A molecular marker map, including Mlo mildew resistance, of the spring barley cross Derkado (Mlo-resistant) × B83-12/21/5 (Mlo-susceptible) was scanned for yield QTLs to determine whether the association of Mlo resistance with reduced yield was due to linkage or pleiotropy. Over the mapped portion of the genome of the cross, the QTL with the greatest effect upon yield was located within a 22 cM region between mlo and the simple sequence repeat HVM67 on chromosome 4(4H). The association of Mlo resistance with lower yield was therefore due to a repulsion linkage. Analysis of yield component characters revealed QTL alleles for reduced grain number and earlier heading date in the same region, also associated with Mlo resistance. Genotyping of a range of cultivars and sources of Mlo resistance with the HVM67 simple sequence repeat showed that the Derkado HVM67 allele was rare as it was found only in one other cultivar and four land-races or sources of disease resistance. Grannenlose Zweizeilige, the source, and Salome, the carrier of Mlo resistance in Derkado, have the same HVM67 genotype, although Salome was a mixture of two genotypes. The entire mlo-HVM67 chromosomal segment from Grannenlose Zweizeilige is therefore thought to have been transmitted to Derkado, possibly through joint selection for Mlo resistance and early heading. L92, synonym EP79, was another source of Mlo resistance with the same HVM67 allele as Derkado but recombination must have occurred during the breeding of Atem as it possesses a different HVM67 allele which is present in all the other Mlo sources and cultivars surveyed. Abbreviations: GN, grains per main stem ear; HD, heading date; MSTGW, thousand grain weight derived from GN and MSY; MSY, yield of grain on the main stem; PY, yield of grain from the whole plot; sCIM, simplified compound interval mapping; SIM, simple interval mapping; SPY, single plant yield; S-SAP, sequence-specific amplification polymorphism; TGW, thousand grain weight derived from bulk of plot seed; TN, number of fertile stems per plant. 相似文献