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ALEX S. WATT 《The New phytologist》1940,39(4):401-422
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DANIEL M. GONZÁLEZ‐TOKMAN ISAAC GONZÁLEZ‐SANTOYO HUMBERTO LANZ‐MENDOZA ALEX CÓRDOBA AGUILAR 《Physiological Entomology》2010,35(4):364-372
Adaptive immunity allows vertebrates to gain protection against repeated pathogenic infections. Analogous responses (priming) have been recently uncovered in invertebrates. However, whether such responses are widespread is not known. The present study investigated the presence of immunological priming in males of a species whose phylogenetic position places it in one of the less derived insect orders. It is hypothesized that the efficiency of such a response could be related to animal condition, as assessed by the expression of a sexually selected ornament. Hetaerina americana Fabricius (Odonata: Calopterygidae) males bear a conspicuous ornament (a red wing spot), which is evolutionarily maintained via male territorial competition. Using field‐collected animals, a group of males is challenged with bacteria before exposure to a higher dose of the same or a different bacteria, and survival is compared with that of infected males not previously challenged, as well as control groups. Gram‐positive and Gram‐negative bacteria are used. To explore how long priming may take to work, the second exposure is carried out either after 1 or 5 days. Red spot and body size are entered in the analysis as predictors of survival within and between groups. There is no difference in survival among groups, which suggests no priming effect. Overall, red spot and body size are not consistent in explaining survival. 相似文献
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This paper deals with experimental designs used in conjoint analysis. The described approach permutes the structure of the underlying fractional experimental design to make different sets of combinations. The resulting experimental designs, suggested to be called Isomorphic Permuted Experimental Designs (IPED), are statistically equivalent to each other while combining diverse sets of the variables and levels into different designs. By facilitating distinctive individual designs (for each respondent), IPEDs reduce a bias caused by some possibly unusually strong performing combinations, and allow detection and estimation of interactions among variables, as well as identification of pattern-based segments emerging from individual models of utilities. This paper examines the theoretical foundation of the approach, formalizes the methodology for algorithmic implementation and shows a practical example of utilization.
Isomorphic Permuted Experimental Design (IPED) allows for overcoming multiple interlinked statistical problems that affect the traditional conjoint analysis approaches, thus leading to more reliable and targeted results in practice. IPED facilitates individual respondents' models based on unique designs, thus allowing for pattern-based segmentation. The approach also allows for the detection of any and all interactions between the elements (features) of the experiments, thus increasing the reliability of conjoint analysis results. It has been utilized in many practical applications, such as for message optimization, early stage new product development, advertising, package and website optimization. 相似文献
PRACTICAL APPLICATIONS
Isomorphic Permuted Experimental Design (IPED) allows for overcoming multiple interlinked statistical problems that affect the traditional conjoint analysis approaches, thus leading to more reliable and targeted results in practice. IPED facilitates individual respondents' models based on unique designs, thus allowing for pattern-based segmentation. The approach also allows for the detection of any and all interactions between the elements (features) of the experiments, thus increasing the reliability of conjoint analysis results. It has been utilized in many practical applications, such as for message optimization, early stage new product development, advertising, package and website optimization. 相似文献
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JULES ANGST THOMAS D. MEYER ROLF ADOLFSSON PETER SKEPPAR MAURO CARTA FRANCO BENAZZI RU‐BAND LU YI‐HSUAN WU HAI‐CHEN YANG CHENG‐MEI YUAN PAOLO MORSELLI PETER BRIEGER JUDITH KATZMANN INES ALICE TEIXEIRA LEÃO JOSÉ ALBERTO DEL PORTO DORIS HUPFELD MORENO RICARDO A. MORENO ODEILTON T. SOARES EDUARD VIETA ALEX GAMMA 《World psychiatry》2010,9(1):41-49
This study examined the transcultural robustness of a screening instrument
for hypomania, the Hypomania Checklist-32, first revised version (HCL-32 R1).
It was carried out in 2606 patients from twelve countries in five geographic
regions (Northern, Southern and Eastern Europe, South America and East Asia).
In addition, GAMIAN Europe contributed data from its members. Exploratory
and confirmatory factor analyses were used to examine the transregional stability
of the measurement properties of the HCL-32 R1, including the influence of
sex and age as covariates. Across cultures, a two-factor structure was confirmed:
the first factor (F1) reflected the more positive aspects of hypomania (being
more active, elated, self-confident, and cogni-tively enhanced); the second
factor (F2) reflected the more negative aspects (being irritable, impulsive,
careless, more substance use). The measurement properties of the HCL-32 R1
were largely invariant across cultures. Only few items showed transcultural
differences in their relation to hypomania as measured by the test. F2 was
higher among men and in more severe manic syndromes; F1 was highest in North
and East Europe and lowest in South America. The scores decreased slightly
with age. The frequency of the 32 items showed remarkable similarities across
geographic areas, with two excep-tions: South Europeans had lower symptom
frequencies in general and East Europeans higher rates of substance use. These
findings support the interna-tional applicability of the HCL-32 R1 as a screening
instrument for hypomania. 相似文献
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Factors influencing Willow Tit Poecile montanus site occupancy: a comparison of abandoned and occupied woods 总被引:1,自引:1,他引:0
The British Willow Tit Poecile montanus kleinschmidti underwent a decline of 85% between 1970 and 2003. The cause of this decline is unknown. However, several hypotheses have been put forward to account for it: competition from other tit species, predation by Great Spotted Woodpeckers Dendrocopos major and habitat change. In order to test these, woods that are currently occupied by Willow Tits were paired with woods (within 50 km) that had been abandoned by Willow Tits five or more years previously. Point counts for other tit species (potential competitors) and woodpecker species (potential predators) were carried out at ten evenly spaced points throughout each wood. Habitat variables were collected within a 50-m radius of where a Willow Tit was located (in the occupied woods) or where maps showed a Willow Tit had been located (for abandoned woods). No evidence was found for differences in numbers of potential competitor or potential predator species in abandoned and occupied woods. Soil water content was found to be higher at occupied sites. No other habitat features differed between the two categories of site. The drying up of British woods could therefore be implicated in the Willow Tit decline and this warrants further investigation. 相似文献
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Research in the soil of the tropics mostly has demonstrated the decline of soil organic carbon (SOC) after conversion of primary forest to plantation and cultivated lands. This paper illustrates the dynamics of SOC on the island of Java, Indonesia, from 1930 to 2010. We used 2002 soil profile observations containing organic carbon (C) analysis in the topsoil, which were collected by the Indonesian Center for Agricultural Land Resources Research & Development from 1923 to 2007. Results show the obvious decline of SOC values from around 2% in 1930–1940 to 0.8% in 1960–1970. However, there has been an increase of SOC content since 1970, with a median level of 1.1% in the year 2000. Our analysis suggests that the human influence and agricultural practices on SOC in Java have been a stronger influence than the environmental factors. SOC for the top 10 cm has shown a net accumulation rate of 0.2–0.3 Mg C ha?1 yr?1 during the period 1990–2000. These findings give rise to optimism for increased soil C sequestration in the tropics. 相似文献
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ALEX GOFMAN 《Journal of sensory studies》2006,21(4):373-414
The article introduces two approaches to identify the direction and magnitude of interaction between concept elements in a conjoint analysis task. Both approaches use main effects experimental designs, permuted to create hundreds of new designs isomorphic to the original design structure. In the first approach, the scenario analysis creates a distinct mutually exclusive and exhaustive set of subgroups from concepts with specific elements, runs a dummy variable regression within each subgroup and identifies the effect of one element on the utilities of the others. In the second approach, the interaction analysis of complete set of raw data forces in the linear terms for the single elements, and then allows significant pair‐wise combinations to enter if they contribute significant additional predictability to the model. The two approaches identify the existence of and then measure the impact of one element on the performance of others (scenario), and the unexpected effect of mixing two concept elements (interaction analysis). The approach is illustrated by two case histories: communicating the sensory and refreshment benefits of an orange beverage, and identifying the features of a cookie. 相似文献