Power series expansion and structural analysis for life cycle assessment

Goal, Scope and Background The usefulness of power series expansion for an LCA system has often been doubted, as those systems may not possess the unique properties that enable power series expansion and analyses based on the power series. This paper surveys the existing literature on power series expansion of monetary input-output system and discusses how the power series expansion can be utilized for more general systems including the LCA model. Methods The inherent properties of matrices that are capable of producing power series forms for their inverse and, further, can utilize structural path analysis are analyzed. Using these analyses, the way how a matrix that is not eligible for structural analyses is converted into an eligible form is investigated. A numerical example is presented to demonstrate the findings. Results The necessary and sufficient condition for an indecomposable, real square technology matrix can be expressed using power series was identified. Two additional conditions for a technology matrix to be utilized for structural analyses using power series expansion are discussed as well. It was also shown that an LCA system that fulfills the Hawkins-Simon condition can be easily converted into the form that is eligible for structural analysis by rescaling the columns and rows. Discussion As a numerical example, an application of accumulative structural path analysis for an LCA system is shown. The implications of the results are discussed in a more plain language as well. Conclusions The survey presented in this paper provides not only the conditions under which a linear system is expressed using a power series form but also the way to appropriately convert a system to utilize the rich analytical tools using power series expansion for structural analyses. Recommendations and Perspectives Widely used LCA databases and software tools have employed the linear systems approach as the basis. Much of these developments in the domain of LCA have been made, however, in isolation of the rich findings of IOA. There will be much to benefit LCA through an active dialogue between the two disciplines. There are rich analytical tools available through the use of power series expansion. The current survey will help software developers and LCA practitioners to apply such tools in LCA.     

Infrageneric relationships of Korean Viola based on eight chloroplast markers

Phylogeny and infrageneric relationships were reconstructed for Korean Viola(Violaceae)using eight chloroplast sequences: the atpB-rbcL intergenic spacer,the atpF-H intergenic spacer,the matK gene,the psbA-trnH intergenic spacer,the psbK-I intergenic spacer,the rpl16 intron,the rpoC1 exon 2,and the trnL-trnF regions.The combined analyses of the eight chloroplast regions suggest that sections Dischidium and Chamaemelanium are monophyletic,whereas section Nomimium is paraphyletic; sections Dischidium and Chamaemelanium form a clade with subsections Hypocarpae and Trigonocarpae of section Nomimium,but unresolved within the clade; two subsections(subsects.Bilobatae and Vaginatae)of section Nomimium form a clade and are placed between the stem and stemless species group; and subsection Patellares of section Nomimium is monophyletic,and Viola dissecta is diverged first in the clade with high support(BS = 100,PP = 100).Our present results support the subsectional grouping based on morphological characteristics,although discordance remained at the series level.     

Decoding cellular deformation from pseudo-simultaneously observed Rho GTPase activities

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Identification of ELF3 as an early transcriptional regulator of human urothelium

Despite major advances in high-throughput and computational modelling techniques, understanding of the mechanisms regulating tissue specification and differentiation in higher eukaryotes, particularly man, remains limited. Microarray technology has been explored exhaustively in recent years and several standard approaches have been established to analyse the resultant datasets on a genome-wide scale. Gene expression time series offer a valuable opportunity to define temporal hierarchies and gain insight into the regulatory relationships of biological processes. However, unless datasets are exactly synchronous, time points cannot be compared directly.     

Statistical modelling and forecasting annual sugarcane production in India: Using various time series models

This paper proposes a comparison of various time series forecasting models to forecast annual data on sugarcane production over 63 years from 1960 to 2022. In this research, the Mean Forecast Model, the Naive Model, the Simple Exponential Smoothing Model, Holt's model, and the Autoregressive Integrated Moving Average time series models have all been used to make effective and accurate predictions for sugarcane. Different scale-dependent error forecasting techniques and residual analysis have been used to examine the forecasting accuracy of these time series models. SE of Residuals, Root Mean Squared Error (RMSE), Mean Absolute Error (MAE) and Akaike's Information Criterion (AIC) are used to analyse the forecast's accuracy. The best model has been selected based on the predictions with the lowest value, according to the three-performance metrics of RMSE, MAE, and AIC. The estimated sugarcane production shows an increasing trend for the next 10 years and is projected to be 37,763.38 million tonnes in the year 2032. Further, empirical results support the plan and execution of viable strategies to advance sugarcane production in India to fulfil the utilisation need of the increasing population and further improve food security.     

Developmental evidence for stamen number reductionin populations of Hibbertia fasciculata (Dilleniaceae)

Discrete Australian populations of Hibbertia fasciculata R. Br. ex DC. differ in stamen number per flower: three to four in isolated, northeastern coastal populations in New South Wales vs. 10–12 in southeastern Australian populations. In all populations, the stamen bases are attached to three broad flat pedestals regardless of number of stamens present. In certain other Hibbertia species, each pedestal results from initiation via a common stamen primordium that usually produces at least 3–4 stamens per common primordium. In H. fasciculata, each of the three pedestals is associated with three to four stamens in flowers of southeastern populations, but with only one stamen per pedestal in the coastal populations of New South Wales. Because the pedestals (remnants of common primordia) have persisted, the evolutionary trend probably has been one of reduction in stamen number. General observations and comparative studies suggest that this population-based reduction series in stamen number (as well as reduced plant size and flower size) reflects a locally successful trend towards smaller organs throughout the plant body together with a shift in pollination ecology.     

Does the level of infant mortality affect the rate of decline?: Time series data from 21 countries

Some scholars have suggested that an inverse care law holds for infant mortality--that infant mortality reductions are more rapid in regions with lower infant mortality. This theory has not been subjected to proper quantitative analysis. This paper examines time series data on infant mortality from 21 countries to test whether percentage reductions in infant mortality are larger when infant mortality is lower. We apply the Dickey-Fuller generalized least squares (DFGLS) unit root test to infant mortality rate (IMR) time series data from 21 mostly European nations for 1870-1988 to test the statistical significance of beta in a regression analysis of Deltaln IMR(t)=alpha+beta ln IMR(t-1)+epsilon(t). Evidence that beta is significant and negative would support the claim that infant mortality declines more rapidly when substantial mortality reductions have already been achieved. With the preferred specification, the DFGLS unit root test rejected the inverse benefit hypothesis in all countries except the Netherlands at the 5% and 10% cutoffs and Australia at the 10% cutoff. The rejection of the inverse benefit hypothesis was robust to alternative specifications of the lag structure of IMR and to transformations of IMR other than logarithmic. Based on late 19th and 20th century data from countries in Europe and Latin America, there is scarce evidence that percentage reductions in infant mortality are generally smaller in higher mortality countries. These findings suggest that large percentage reductions in infant mortality are possible for countries at any stage in economic development and are reflective of durable advances in human knowledge, social institutions and physical capital.     

Rotation gene set testing for longitudinal expression data

Gene set analysis methods are popular tools for identifying differentially expressed gene sets in microarray data. Most existing methods use a permutation test to assess significance for each gene set. The permutation test's assumption of exchangeable samples is often not satisfied for time‐series data and complex experimental designs, and in addition it requires a certain number of samples to compute p‐values accurately. The method presented here uses a rotation test rather than a permutation test to assess significance. The rotation test can compute accurate p‐values also for very small sample sizes. The method can handle complex designs and is particularly suited for longitudinal microarray data where the samples may have complex correlation structures. Dependencies between genes, modeled with the use of gene networks, are incorporated in the estimation of correlations between samples. In addition, the method can test for both gene sets that are differentially expressed and gene sets that show strong time trends. We show on simulated longitudinal data that the ability to identify important gene sets may be improved by taking the correlation structure between samples into account. Applied to real data, the method identifies both gene sets with constant expression and gene sets with strong time trends.