Activity-dependent long-term depression of electrical synapses     

Haas JS  Zavala B  Landisman CE 《Science (New York, N.Y.)》2011,334(6054):389-393

Use-dependent forms of synaptic plasticity have been extensively characterized at chemical synapses, but a relationship between natural activity and strength at electrical synapses remains elusive. The thalamic reticular nucleus (TRN), a brain area rich in gap-junctional (electrical) synapses, regulates cortical attention to the sensory surround and participates in shifts between arousal states; plasticity of electrical synapses may be a key mechanism underlying these processes. We observed long-term depression resulting from coordinated burst firing in pairs of coupled TRN neurons. Changes in gap-junctional communication were asymmetrical, indicating that regulation of connectivity depends on the direction of use. Modification of electrical synapses resulting from activity in coupled neurons is likely to be a widespread and powerful mechanism for dynamic reorganization of electrically coupled neuronal networks.  相似文献   

Biological information specialists for biological informatics     

P Bryan Heidorn  Carole L Palmer  Dan Wright 《Journal of Biomedical Discovery and Collaboration》2007,2(1):1

Data management and integration are complicated and ongoing problems that will require commitment of resources and expertise from the various biological science communities. Primary components of successful cross-scale integration are smooth information management and migration from one context to another. We call for a broadening of the definition of bioinformatics and bioinformatics training to span biological disciplines and biological scales. Training programs are needed that educate a new kind of informatics professional, Biological Information Specialists, to work in collaboration with various discipline-specific research personnel. Biological Information Specialists are an extension of the informationist movement that began within library and information science (LIS) over 30 years ago as a professional position to fill a gap in clinical medicine. These professionals will help advance science by improving access to scientific information and by freeing scientists who are not interested in data management to concentrate on their science.  相似文献   

Optimization of extraction of apple aroma by dynamic headspace and influence of saliva on extraction of volatiles     

Mehinagic E  Prost C  Demaimay M 《Journal of agricultural and food chemistry》2004,52(16):5175-5182

The dynamic headspace procedure of aroma extraction was optimized on Gala apples (Malus domestica). Two parameters affecting the extractability of compounds were studied: temperature and purge time. The influence of artificial saliva was also included. An increase in purge time and temperature caused an increase in the extraction of volatiles from the apple matrix. The optimum point of extraction was 40 degrees C and 70 min of purge. The study also showed that the addition of saliva influenced the extraction of volatile compounds, but this effect was different from one compound to another. To verify that the headspace extracts presented a global odor representativeness of fresh apple under these conditions of extraction, eight assessors compared the odor of extracts with fresh fruit odor for three different cultivars. With regard to the sensory profiles of extracts, the optimal conditions of extraction were suitable for extraction of volatile compounds, even if cooked apple odor appeared in some extracts. The similarity marks of extracts were low but acceptable.  相似文献   

Foliar Nitrogen as an Indicator of Nitrogen Deposition and Critical Loads Exceedance on a European Scale     

Carole E.R. Pitcairn  Ian D. Leith  David Fowler  Ken J. Hargreaves  Masoud Moghaddam  Valerie H. Kennedy  Lennart Granat 《Water, air, and soil pollution》2001,130(1-4):1037-1042

The foliar N content of bryophytes and Calluna vulgaris (L.) has been shown to be an indicator of atmospheric N deposition in the UK at a regional scale (1000km) and more recently on a smaller scale in the vicinity of intensive livestock farms. This work extends the geographical scale of the relationship between foliar N concentration of Calluna vulgaris and other ericaceous shrubs and N deposition with 2 measurement transects, one extending from northern Finland to southern Norway (2000 km) and the other extending from central Sweden to Stockholm, south east Sweden (330 km). Included in the second transect is a region of complex terrain in the Transtrand uplands, where the variation in N deposition with altitude and canopy cover was quantified using ²¹⁰Pb inventories in organic soil. The relationship between foliar N (F_N) and N deposition was shown to increase linearly with N deposition (N_D) over the range 0.8% N to 1.4% N according to F_N = 0.040N_D + 0.793 (r² = 0.70). The data are entirely consistent with earlier studies which together provide a valuable indicator of critical loads exceedance, the threshold value being approximately 1.5% N, which is equivalent to a N deposition of 20 kg N ha^?1 y^?1.  相似文献   

A phylogenetic analysis of Bovine Viral Diarrhoea Virus (BVDV) isolates from six different regions of the UK and links to animal movement data     

Richard E Booth  Carole J Thomas  Laila MR El-Attar  George Gunn  Joe Brownlie 《Veterinary research》2013,44(1):43

Bovine Viral Diarrhoea Virus (BVDV) is a pestivirus which infects cattle populations worldwide and is recognised as a significant source of economic loss through its impact on health and productivity. Studies investigating the molecular epidemiology of BVDV can give invaluable information about the diversity of viral strains present in a population and this, in turn, can inform control programs, drive vaccine development and determine likely infection sources. The current study investigated 104 viral isolates from forty farms across the UK. Through phylogenetic and nucleotide sequence analysis of the 5′UTR and N^pro regions of the isolates investigated, it was determined that BVDV 1a was the predominant sub-genotype. However, BVDV 1b, 1e and 1i were also identified and, for the first time in the UK, BVDV 1d. Through analysis of animal movement data alongside the phylogenetic analysis of these BVD isolates, it was possible to link animal movements to the viral isolates present on several premises and, for the first time, begin to elucidate the routes of viral transmission. With further work, this type of analysis would enable accurate determination and quantification of the true biosecurity risk factors associated with BVDV transmission.  相似文献   

Effects of 28% Protein Diets Differing in Quality on Channel Catfish Performance,Processing Traits,and Production Economics in a Multi-Batch System     

Carole Engle  Ganesh Kumar  Rebecca Lochmann  Brian Bosworth  Miles Thompson 《Journal Of Applied Aquaculture》2013,25(2):102-112

Three 28% protein feeds (premium, standard, or a low-cost diet) were fed to channel catfish in a pond study to compare growth, production, and costs as a follow up to similar work with 32% protein feeds. Twelve 0.1-ha earthen ponds at the University of Arkansas at Pine Bluff (UAPB) Aquaculture Research Station were stocked with carryover fish (0.39 kg mean weight) at 5,860 fish/ha and fingerling catfish (mean individual weight of 15.4 g) at 12,500 fish/ha. Total yield (gross and net) did not differ between fish fed the premium as compared to the standard diet, but that of the premium diet was significantly higher than that of fish fed the low-cost diet. The feed conversion ratio (FCR) did not differ between fish fed the premium and standard diets, but was lower than the FCR of fish fed the low-cost diet. There were no differences found in processing yields among treatments. Given the lower cost of the 28% standard diet and yields equivalent to those of the 28% premium diet, the 28% standard diet was economically preferable to the other diets tested.  相似文献   

INTRODUCTION     

Carole Engle Editor 《Aquaculture Economics & Management (Blackwell Science)》2013,17(1)

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A LATENT CLASS MODEL FOR ANALYZING PREFERENCES FOR CATFISH     

Kwamena K. Quagrainie  Carole R. Engle 《Aquaculture Economics & Management (Blackwell Science)》2013,17(1):1-14

ABSTRACT

Using a latent class model of structural heterogeneity in the multinomial logit framework, this study examined catfish preferences of Arkansas restaurateurs from stated choice data. The results suggest two latent classes of restaurateurs that are fairly distinct and have some degree of overlap. Managers in both classes are sensitive to prices and prefer catfish products that have mild flavor and soft texture. When preference for dryness, flavor and texture are assumed equal for both classes, one class becomes very sensitive to price but unconcerned with color while the other class becomes insensitive to price but very concerned with color.  相似文献   

Genetic variation among <Emphasis Type="Italic">Fusarium</Emphasis> isolates from onion,and resistance to <Emphasis Type="Italic">Fusarium</Emphasis> basal rot in related <Emphasis Type="Italic">Allium</Emphasis> species   总被引：2，自引：0，他引：2  

Guillermo A. Galván  Carole F. S. Koning-Boucoiran  Wim J. M. Koopman  Karin Burger-Meijer  Pablo H. González  Cees Waalwijk  Chris Kik  Olga E. Scholten 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(4):499-512

The aim of this research was to study levels of resistance to Fusarium basal rot in onion cultivars and related Allium species, by using genetically different Fusarium isolates. In order to select genetically different isolates for disease testing, a collection of 61 Fusarium isolates, 43 of them from onion (Allium cepa), was analysed using amplified fragment length polymorphism (AFLP) markers. Onion isolates were collected in The Netherlands (15 isolates) and Uruguay (9 isolates), and received from other countries and fungal collections (19 isolates). From these isolates, 29 were identified as F. oxysporum, 10 as F. proliferatum, whereas the remaining four isolates belonged to F. avenaceum and F. culmorum. The taxonomic status of the species was confirmed by morphological examination, by DNA sequencing of the elongation factor 1-α gene, and by the use of species-specific primers for Fusarium oxysporum, F. proliferatum, and F. culmorum. Within F. oxysporum, isolates clustered in two clades suggesting different origins of F. oxysporum forms pathogenic to onion. These clades were present in each sampled region. Onion and six related Allium species were screened for resistance to Fusarium basal rot using one F. oxysporum isolate from each clade, and one F. proliferatum isolate. High levels of resistance to each isolate were found in Allium fistulosum and A. schoenoprasum accessions, whereas A. pskemense, A. roylei and A. galanthum showed intermediate levels of resistance. Among five A. cepa cultivars, ‘Rossa Savonese’ was also intermediately resistant. Regarding the current feasibility for introgression, A. fistulosum, A. roylei and A. galanthum were identified as potential sources for the transfer of resistance to Fusarium into onion.  相似文献   

Psychology. Money is material     

Burgoyne CB  Lea SE 《Science (New York, N.Y.)》2006,314(5802):1091-1092

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