Inheritance of cabbage head formation in crosses of cabbage × ornamental cabbage and cabbage × kale

We investigated the inheritance of head formation in Brassica oleracea by using two crosses, cabbage × ornamental cabbage and cabbage × kale. The degree of head formation (DHF) was classified into nine grades ranging from non‐heading to full heading. DHF in the two F₂ populations showed a continuous distribution. The variance of F₃ offspring selected for full heading or non‐heading was large. The DHF distributions in the F₃ offspring selected for moderate heading or randomly selected F₃ populations were similar to those of the respective F₂ populations, but had smaller average values and variance. However, the realized heritability in F₃ offspring was similar in full‐heading and non‐heading selections. Our findings suggest that head formation is a quantitative trait controlled additively with low dominance effects. In comparisons of leaf developmental patterns among the parents, only cabbage showed a change in leaf shape becoming wider because of the shorter petiole length with increasing leaf position. These findings suggest that cabbage acquired the developmental changes in leaves required to form a head during the process of domestication.     

Contributions to the Analysis of Genotype × Environment Interactions: Comparison of Different Parametric and Non-parametric Tests for Interactions with Emphasis on Crossover Interactions

The objective of this study was to compare five statistical procedures (analysis of variance, the Azzalini/Cox test, the Hildebrand procedure, the Kubinger approach, and the de Kroon/van der Laan technique) for the analysis of genotype × environment interactions in cross‐classified data sets from cultivar performance yield trials with rows = cultivars and columns = environments (locations and/or years). The procedures Hildebrand, Kubinger and de Kroon/van der Laan are non‐parametric methods based on ranks, while analysis of variance and the Azzalini/Cox test proceed from the original absolute yield data. These very different statistical techniques were applied to extensive data sets from German official registration trials (1985–1989) with winter oilseed rape (Brassica napus L.), faba bean (Vicia faba L.), oat (Avena sativa L.), fodder beet (Beta vulgaris L.) and sugar beet (Beta vulgaris L.). The Azzalini/Cox and de Kroon/van der Laan methods are based on the crossover concept of interaction (different rank orders) while the other methods are based on the usual concept of interaction (deviations from additivity of main effects). For an analysis of usual interactions the procedures Hildebrand, Kubinger and analysis of variance are approximately equivalent. For the crossover concept of interaction, the Azzalini/Cox approach is recommended, especially if one is particularly interested in rank changes between environments within genotypes.     

Identification of genetic variation in Brassica napus seeds for tocopherol content and composition using near‐infrared spectroscopy technique

Tocopherol is an essential fat‐soluble nutrient for humans. Increasing the tocopherol content in Brassica napus seeds can add value to rapeseed vegetable oil; this has become an important breeding target. However, there is no efficient and non‐destructive method for selecting rapeseed accessions with high tocopherol contents. Here, we report the first near‐infrared reflectance spectroscopy (NIRS)‐based technique for predicting rapeseed tocopherol content. Individual seed tocopherol compositions were estimated from 373 rapeseed genotypes of different origins. This method and chemical methods produced comparable predicted values of the tocopherol constituents in the seeds. Three equations were generated for the prediction of tocopherol content by using a modified partial least squares (MPLS) model. The total tocopherol content for the determination coefficient of cross‐validation (R²_cv) (0.74), determination coefficient (RSQ) (0.76) and one minus the ratio of unexplained variance to total variance (1‐VR) (0.65) values indicates a strong correlation between the calibration and validation sets. Overall, our model confirmed the NIRS method as feasible for predicting tocopherol content in rapeseed and as an efficient screening tool for future breeding programs.     

Rent Revenue Analysis of Domestic "House Bank"

House Bank" is a new mode of house tenancy, in which the rent income in free-rent period is the primary revenue source. The rent income in free-rent period mainly depends on values of house rent and free-rent period and leasing house quantity. In this paper, the rule of in-and-out house quantity variation in a given period is analyzed. It demonstrates that the probability of in-and out quantity of house in a period meets the four characters of Poisson distribution and consequently this probability meets the Poisson distribution. Based on the characters of Poisson distribution, in this paper, the rent revenue of "House Bank" is analyzed and the way to find reasonable free-rent period is discussed.     

非独立试验数据的一般线性混合模型分析

传统方差分析模型的假设条件之一是试验数据相互独立,实际的试验数据未必能满足其条件,这使方差分析的应用范围和分析的效果受到限制。近年来,一般线性混合模型得到发展,为分析非独立试验数据提供了新途径。本文讨论了一般线性混合模型分析非独立试验数据的方法及其在SAS软件的实现,对小麦品比和玉米灌溉2个不同试验的非独立数据进行了一般线性混合模型与方差分析模型的对比分析。结果表明,与传统方差分析法相比,一般线性混合模型数据拟合效果好,在小麦品比试验使小麦品系效应比较的平均标准误降低18.4%,平均分析相对效率为1.5,而在玉米灌溉试验使灌溉效应比较和品种×灌溉交互效应比较的平均标准误降低9.1%￣10.8%,平均分析相对效率均约为1.2。因此,对非独立试验数据,一般线性混合模型分析的准确性和效率要比传统方差分析模型高。     

Is heterosis an artefact governed by the choice of scale?

When estimating heterosis it is often necessary to transform either the data or, within the context of generalized linear models, the linear predictor, to satisfy certain assumptions. In this note it will be argued that the amount of heterosis is scale-dependent varying with the kind of transformation. The same applies for the examination of dominance in quantitative genetics. We exemplify the varying heterotic effect with phenotypic data of maize roots. Either a data transformation or a generalized linear mixed model with appropriately chosen link function is applied to the data. It is concluded that care should be exercised when transforming data in phenotypic as well as quantitative-genetic studies because partial dominance or heterosis may be removed by a suitably chosen transformation. With data transformations, even overdominance or better parent heterosis may disappear. When a data transformation is needed to meet the usual statistical assumptions such as normality and homogeneity of variance, a back-transformation to the original scale may be necessary, depending on what is deemed the appropriate scale for assessing genetic effects.     

Systemic View on Heading and Overwintering: Are They Always Opposed?

The study investigated the cultivars of non‐obligatorily requiring vernalization plant Festulolium braunii and assessed the influence of non‐hardy reproductive and hardy vegetative structures on overwintering effect. The study was conducted taking into account systemic relations between these types of structures. The results show the cultivars differ according to the percentage of headed and overwintered plants, when the cultivars with the most abundant heading – ‘Felopa’ and ‘Sulino’ – are also better at overwintering. The positive correlation between heading and overwintering characteristics was also observed, what seemed to be a rather new finding. It can be explained by systemic effect: non‐hardy later reproductive structures induce the post‐generative regrowth of vegetative shoots, which during shorter days halt development and become potentially hardy. More detailed interpretation is also provided including discussion of causal mechanisms of the detected phenomenon. The authors suppose that these mechanisms constitute a survival strategy for such perennial plants. The observed late heading which represents reproductive structures could be applied in plant breeding as a marker of winter‐hardiness among perennial grass plants which non‐obligatorily demand vernalization.     

Analysis of a Long-term Experiment with Repeated-measurement Models

Long‐term experiments are a classical case of repeated measurements. Traits are measured on the same experimental unit over many years so that correlations arise between the observations made on the same plot in consecutive years. This paper describes the analysis of a three‐crop‐rotation long‐term experiment. We analysed the yields of the crops and the organic carbon content in the topsoil over 30 consecutive years. Several variance–covariance approaches are discussed and the trait‐specific best fit is interpreted. Mixed models are used to describe the structure of the experiment. Both yields and soil organic carbon show a more or less pronounced variance heterogeneity. Especially for yields, the heterogeneity of cycles and years is dominant. The consideration of correlations results in a better model fit in all cases.     

Standard errors of heritabilities based on perennial observations,with application to Yorkshire Fog grass

Summary The variance of heritability ratios are considered for cases where data from perennial genotypes are collected serially over time. A random effect model for randomised complete blocks at a single location is examined. Estimation of the variance of estimates of heritability is presented for three types of heritability definition.Estimators are applied to two characters in a Yorkshire Fog grass germplasm collection evaluated for two years at one site. The precision of such heritability estimates is discussed. Estimators for the multiple sites model are available also, from the author.     

A Statistical Model for Multi-paths Distribution under Mobile Environment

This paper presents the distribution function of multi paths by use of two stochastic processes. The first process which is a Poisson process presents the paths occurring, and the second one which is an exponential process presents the paths standing. If the maximal paths are infinite, the Poisson distribution can be concluded. The notable error exists between the Poisson model and the measurement result. So the Poisson model is modified depending on the fact that the arrival rate decreases and the standing time get longer with the increase of arrived paths. The numeric results verify the consistence between the modified model and measurement.     

Renormalization Model and Its Application in Instability and Failure of Rock

The critical phenomenon in rock failure is analyzed with renormalization model on the assumption that strength of rock fallows probability distribution and self-similar characteristic. The experimental results are introduced. The calculation results given by renormalization model are in good accordance with experimental results. This show that the theoretical failure point of rock and evolutionary process of rock mass can be simulated accurately by renormalization model. Normalization model can be adopted to judge whether the rock start to fail or not.     

Interval Probability Random Variable and Its Numerical Characters

In this paper,based on the idea of fuzzy number origin,an interval probability space of the finite origin is established by the operation of fuzzy probability.Definitions of interval probability random variable (vecter) and it,s distribution function,distribution sequence,math expectation,variance and so on are given,and some special operation rules on them are studied.     

Using Hemispherical Radiation Measurements to Predict Weight-Related Growth Traits in Oilseed Rape (Brassica napus L.) and Barley (Hordeum vulgare L.) Canopies

Methods for determining growth traits in the field are mostly work‐intensive and/or often erroneous. Further development of multi‐temporal techniques of growth analyses provided by fast and non‐destructive tools for monitoring canopy properties may result in a substantial gain for practical use. Among them, the LAI‐2000 Canopy Analyzer can be used to determine the canopy area index (CAI) resulting from radiation measurements. In plant breeding, single‐date measurements were usually made across a wide number of genoptypes. In contrast, multi‐temporal information on canopy status is needed in agronomy. In our study, data of the CAI based on hemispherical radiation measurements with the LAI‐2000 were used to estimate developmental courses of weight‐related growth traits. For this purpose, seasonal courses of shoot fresh matter, shoot dry matter, shoot N and water content and CAI of winter oilseed rape (Brassica napus L.) and spring barley (Hordeum vulgare L.) were investigated simultaneously in field experiments from 2002 to 2006 in northern Germany with and without nitrogen (N) fertilization. Courses of 2003 and 2004 were used to calculate relationships between CAI and growth traits. Results show that each of the weight‐related growth trait is related to the CAI. In this mechanistic approach relationships were found gathered across 2 years, two N‐treatments and several growth stages being unaffected by N‐fertilization, cultivar and experimental year. These relationships were verified using independent data sets of the years 2005 (winter oilseed rape and spring barley) and 2006 (winter oilseed rape). The results of the current study show that the use of LAI‐2000 and its rapid and non‐destructive determination of weight‐related growth traits over the entire growth period will substantially improve the determination of weight‐related growth traits in agriculture.     

Differential Employment Patterns for Citizens and Non‐Citizens in Science and Engineering in the United States: Minting and Competitive Effects

ABSTRACT The consequences of the heavy inflow of foreign talent for U.S. scientists and engineers over the period 1973‐1997 are examined using data from the Survey of Doctorate Recipients. Of particular interest is whether non‐citizens trained in the United States have displaced citizens from jobs in science and engineering (S&E). Using a novel adaptation of the shift‐share technique, it is shown that citizen S&E doctorates have fewer jobs in S&E and fewer academic jobs than their non‐citizen counterparts for two reasons: the citizen doctoral population has experienced slower growth than the non‐citizen doctoral population, and citizen S&E doctorates have been displaced. Whether the displacement observed was a voluntary response of citizens to the lure of better opportunities elsewhere or an involuntary response indicative of having been pushed out by foreign talent remains to be determined.     

Nitrogen, Phosphorus, Potassium, Magnesium and Calcium Removal by Brown Midrib Sorghum Sudangrass in the Northeastern USA

For the long‐term sustainability of the dairy industry in the Northeastern USA, manure nutrient application rates should not exceed crop nutrient removal once above‐optimum soil fertility levels are reached. Dairy producers have shown a growing interest in brown midrib (BMR) forage sorghum (Sorghum bicolor (L.) Moench.) × sudangrass (Sorghum sudanense Piper) hybrids (S × S) as a more environmentally sound alternative to maize (Zea mays L.) but data on S × S nutrient removal rates are scant. Our objectives were to determine N, P, K, Ca and Mg removal with harvest as impacted by N application rate, using six N rate studies in New York. One of the six sites had a recent manure history. Although site‐to‐site differences existed, N application tended to decrease P and K and increase N, Ca and Mg concentrations in BMR S × S forage. Nutrient removal and yield were highly correlated for all sites except one location that showed a K deficiency. The crop removed large amounts of P and K in the manured site, suggesting that BMR S × S is an excellent scavenger of these nutrients. If manure is applied mid‐season, forage K levels are likely too high for feeding to non‐lactating cows.     

Growth and Location of Economic Activity: The Spatial Dynamics of Industries in Canada 1971–2001

ABSTRACT A growing literature has accumulated that points to the stability of industrial location patterns. Can this be reconciled with spatial dynamics? This article starts with the premise that demonstrable regularities exist in the manner in which individual industries locate (and relocate) over space. For Canada, spatial distributions of employment are examined for seventy‐one industries over a thirty‐year period (1971–2001). Industry data is organized by “synthetic regions” based on urban size and distance criteria. “Typical” location patterns are identified for industry groupings. Industrial spatial concentrations are then compared over time using correlation analysis, showing a high degree of stability. Stable industrial location patterns are not, the article finds, incompatible with differential regional growth. Five spatial processes are identified, driving change. The chief driving force is the propensity of dynamic industries to start up in large metro areas, setting off a process of diffusion (for services) and crowding out (for manufacturing), offset by the centralizing impact of greater consumer mobility and falling transport costs. These changes do not, however, significantly alter the relative spatial distribution of most industries over time.     

An EOQ Model at Random when Average Demand Is a Linear Increasing Function

For certain types of inventory, the ordering cycle and demand may be random variants, which satisfy certain types distribution. The classical EOQ model usually neglects the fact. Based on the constant demand, under the hypothesis that the ordering cycle is a random variant which satisfies exponent distribution, average demand is a linear increasing function, this paper considers the effects of the time-value of capital and inflation on replenishment strategy of inventory system. Loosening the condition of basic economic order quantity model under deterministic state, the total cost function of the model is provided. The optimum order quantity and cycle are obtained. The application range of EOQ model under the constant demand is widened. The theoretical evidence is provided for the inventory system to make management decision.     

应用三维数字化仪对玉米植株叶片方位分布的研究

采用三维数字化仪在田间原位测量了玉米(品种为农大108)植株生长过程中每个叶片中脉在空间坐标系中的位置,据此计算出植株每个叶片的方位角,应用对方向数据的统计分析方法对植株叶片的空间伸展方向规律进行了研究,并分析了单个叶片在生长过程中方位角的变化规律。结果表明,(1) 单株叶位越高叶片偏离植株方位平面的程度越大。叶片方位角从露尖到完全展开前3 d变化较大,最大可达150°,此后基本不变。(2) 种植行向与行距相同(0.6 m)而株距不同(分别为0.3 m和0.6 m)的2个处理的玉米群体中各植株方位平面取向分布均匀,但株距影响叶片在植株方位平面附近的分散程度,株距小的植株叶片方向对植株方位平面的偏离大,其第9~13片叶分散程度与宽株距处理对应叶片差异显著,但没有发现上层叶片有明显转向行间的趋势。     

New Insights into Senior Travel Behavior: The Canadian Experience

Societies in many developed nations around the world are aging. Over the past decade, a growing body of research has emerged internationally in an effort to anticipate and prepare for the transport challenges posed by this unprecedented demographic change. This paper contributes to this line of research by offering new insights into senior travel behavior focusing on the recent Canadian experience. Using weekday data from the 1992 and 2005 General Social Surveys on time use, changes in the number of trips, the duration of trips, trip mode, and trip timing are evaluated for urban seniors. In contrast to the experiences of many other developed nations, analysis of the first three indicators of behavioral change refutes the notion that “automobility” has increased in Canada over the 13‐year period. While this finding is encouraging, it is tempered by the fact that Canadian seniors who choose to travel by car are doing so increasingly during the morning and evening peak periods. The results from a peak versus non‐peak departure‐time model that pools data from both years offer important insights into factors driving this change. For instance, the results suggest that the propensity to start a trip during rush hour has increased over time for non‐work trip purposes.