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51.
Hand evaluation and mouth evaluation were compared for texture of cheese. Panelists (n = 11) identified seven mouth terms and five hand terms and developed definitions and standard procedures for evaluation during the course of training. The terms were used to evaluate texture properties of fourteen different types of natural and processed full fat and reduced fat cheeses. Hand and mouth evaluation were able to discriminate cheese texture (P≦0.05). Principal component analysis of data revealed that hand and mouth evaluation differentiated the cheeses in a similar manner. Correlation analysis, factor analysis, and canonical analysis revealed that mouth and hand terms were highly correlated (P≦0.05). Either hand or mouth evaluation can be used to discriminate cheese texture. 相似文献
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Although northern peatlands cover only 3% of the land surface, their thick peat deposits contain an estimated one‐third of the world's soil organic carbon (SOC). Under a changing climate the potential of peatlands to continue sequestering carbon is unknown. This paper presents an analysis of 6 years of total carbon balance of an almost intact Atlantic blanket bog in Glencar, County Kerry, Ireland. The three components of the measured carbon balance were: the land‐atmosphere fluxes of carbon dioxide (CO2) and methane (CH4) and the flux of dissolved organic carbon (DOC) exported in a stream draining the peatland. The 6 years C balance was computed from 6 years (2003–2008) of measurements of meteorological and eddy‐covariance CO2 fluxes, periodic chamber measurements of CH4 fluxes over 3.5 years, and 2 years of continuous DOC flux measurements. Over the 6 years, the mean annual carbon was ?29.7±30.6 (±1 SD) g C m?2 yr?1 with its components as follows: carbon in CO2 was a sink of ?47.8±30.0 g C m?2 yr?1; carbon in CH4 was a source of 4.1±0.5 g C m?2 yr?1 and the carbon exported as stream DOC was a source of 14.0±1.6 g C m?2 yr?1. For 2 out of the 6 years, the site was a source of carbon with the sum of CH4 and DOC flux exceeding the carbon sequestered as CO2. The average C balance for the 6 years corresponds to an average annual growth rate of the peatland surface of 1.3 mm yr?1. 相似文献
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ALAN C. SWANN JOEL L. STEINBERG MARIJN LIJFFIJT GERARD F. MOELLER 《World psychiatry》2009,8(3):166-172
Bipolar mixed states combine depressive and manic features, presenting diagnostic and treatment challenges and reflecting a severe form of the illness. DSM-IV criteria for a mixed state require combined depressive and manic syndromes, but a range of mixed states has been described clinically. A unified definition of mixed states would be valuable in understanding their diagnosis, mechanism and treatment implications. We investigated the manner in which depressive and manic features combine to produce a continuum of mixed states. In 88 subjects with bipolar disorder (DSM-IV), we evaluated symptoms and clinical characteristics, and compared depression-based, mania-based, and other published definitions of mixed states. We developed an index of the extent to which symptoms were mixed (Mixed State Index, MSI) and characterized its relationship to clinical state. Predominately manic and depressive mixed states using criteria from recent literature, as well as Kraepelinian mixed states, had similar symptoms and MSI scores. Anxiety correlated significantly with depression scores in manic subjects and with mania scores in depressed subjects. Discriminant function analysis associated mixed states with symptoms of hyperactivity and negative cognitions, but not subjective depressive or elevated mood. High MSI scores were associated with severe course of illness. For depressive or manic episodes, characteristics of mixed states emerged with two symptoms of the opposite polarity. This was a cross-sectional study. Mixed states appear to be a continuum. An index of the degree to which depressive and manic symptoms combine appears useful in identifying and characterizing mixed states. We propose a depressive or manic episode with three or more symptoms of the opposite polarity as a parsimonious definition of a mixed state. 相似文献
54.
Differential pollination success in the course of individual flower development and flowering time in Gentiana pneumonanthe L. (Gentianaceae) 总被引:3,自引:0,他引:3
THEODORA PETANIDOU ALBEFTINE C. ELLIS-ADAM HANS C. M. DEN NIJS J. GERARD B. OOSTERMEIJER 《Botanical journal of the Linnean Society. Linnean Society of London》2001,135(1):25-33
The effect of flowering time and anthesis stage on fecundity of Gentiana pneumonanthe L. (Gentianaceae) in a greenhouse experiment was studied. The species is self-compatible, not apomictic, and rarely self-pollinates spontaneously. On average, flowers lived for 11.4 days, starting with a male stage of 3.6 and continuing with a female stage of 7.9 days. Pollen viability was highest during the first two days of the male stage, but never exceeded 50%. Seed-set from cross-pollination was higher earlier in the flowering period (77%) than later (63Vo). For self-pollinations, no significant difference was observed. The success of hand-pollinations declined dramatically after the fourth day of the female stage. Self-pollination yielded lower seed-set on the first day of the female stage than on the following three days. Also, there was a significant difference in seed-set between self- and cross-pollinations (25% vs 55%, respectively) only on the first day. This suggests that selection against self pollen was stronger during the first stage of the female phase and weakened as the stylar tissue aged. In conclusion, two different ways to enhance outcrossing were observed: (1) within the population's flowering period, and (2) within an individual flower's lifespan. Both may have important effects on the genetic variability of G. pneumonanthe offspring under unfavourable conditions. Wese include small population size (associated with reduced pollinator service), general pollinator scarcity, or rainy summers. 相似文献
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1. Within‐species phenotypic variation is hugely variable and may play a role in determining the range of habitats a species can exploit. Our study addressed two main questions: 1. does phenotypic variation allow some species (i.e. habitat‐generalists) to use heterogeneous habitats and 2. are habitat‐generalists more variable than species occupying relatively homogeneous environments (i.e. habitat‐specialists)? 2. We examined the morphology of the common bully (Gobiomorphus cotidianus), a habitat‐generalist eleotrid fish found in lakes and rivers throughout New Zealand. We also compared the level of morphological variability in common bullies with that in the closely related redfin bully (Gobiomorphus huttoni), a habitat‐specialist of moderate‐ and fast‐flowing rivers. 3. Common and redfin bullies were collected from the South Island of New Zealand. A series of body and fin measurements were made, and cephalic dorsal head pores of the mechanosensory lateral‐line system were counted. The pores and associated canal neuromasts are important for prey detection and predator avoidance in other species, particularly, in turbulent conditions where the effectiveness of superficial neuromasts may be compromised. 4. The common bully had more dorsal head pores in fish from rivers than in those from lakes. This pattern was apparent only in adults, suggesting that selective pressures associated with adult habitat, be it rivers or lakes, are responsible. 5. As expected, there was greater phenotypic variability in the generalist common bully than in the specialist redfin bully, particularly with regard to the sensory pores, suggesting their importance for survival in turbulence. 6. We identified habitat‐related patterns in phenotypic variability in a generalist species and demonstrated a link between phenotypic variability and habitat breadth. Variation in the common bully may explain its ability to occupy a range of habitats. 相似文献
59.
ANNA PONJOAN GERARD BOTA ELADIO L. GARCÍA DE LA MORENA MANUEL B. MORALES AXEL WOLFF IGNASI MARCO SANTI MAÑOSA 《The Journal of wildlife management》2008,72(1):315-319
Abstract Capturing wild animals for research or conservation purposes may cause some adverse effects, which is only acceptable if these are outweighed by conservation benefits. We used information from 3 on-going telemetry studies on the endangered little bustard (Tetrax tetrax) in Western Europe to evaluate the risk factors associated with capture and handling. Of 151 telemetered birds, 23 (15.2%) exhibited impaired mobility and coordination after release, probably related to the occurrence of capture myopathy. Among the 23 impaired birds, 10 (43.5%) died before recovering normal mobility (6.6% of all birds captured). Logistic regression analyses identified longer handling time, longer restraint time, use of cannon nets, and capture of juveniles as inducing factors for these disorders. We conclude that little bustard is fairly susceptible to suffering ataxia and paresia after release as a result of restraint associated with capture and manipulation. Researchers can reduce this risk by keeping handling and restraint time below 10–20 minutes, particularly when using cannon nets or when capturing juveniles. 相似文献
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