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Brown algae have convergently evolved plant-like body plans and reproductive cycles, which in plants are controlled by differential DNA methylation. This contribution provides the first single-base methylome profiles of haploid gametophytes and diploid sporophytes of a multicellular alga. Although only c. 1.4% of cytosines in Saccharina japonica were methylated mainly at CHH sites and characterized by 5-methylcytosine (5mC), there were significant differences between life-cycle stages. DNA methyltransferase 2 (DNMT2), known to efficiently catalyze tRNA methylation, is assumed to methylate the genome of S. japonica in the structural context of tRNAs as the genome does not encode any other DNA methyltransferases. Circular and long noncoding RNA genes were the most strongly methylated regulatory elements in S. japonica. Differential expression of genes was negatively correlated with DNA methylation with the highest methylation levels measured in both haploid gametophytes. Hypomethylated and highly expressed genes in diploid sporophytes included genes involved in morphogenesis and halogen metabolism. The data herein provide evidence that cytosine methylation, although occurring at a low level, is significantly contributing to the formation of different life-cycle stages, tissue differentiation and metabolism in brown algae.

Literature on the impacts of COVID 19 reveals thathow the effects of the pandemic may be experienced at destinations in different stages of their development has not been studied. This paper discusses the impact of a break in tourism visitation to destinations caused by COVID 19 and uses the Tourism Area Life Cycle model as a framework from which to argue that the scale and importance of the impacts on destinations will vary depending on the stage of the development cycle reached by any specific destination. Such impacts may range from a short term and temporary loss of tourists to a permanent departure of the destination from tourism. It is argued that the nature and degree of recovery of the tourism market at any specific destination will vary in speed and level of recovery, the degree of permanence of impacts, and the likelihood of destinations retaining their overall appeal after the pandemic has ended, depending on their stage of development. The paper concludes with a discussion of the possibility of destinations using the pandemic to reposition themselves in terms of their markets, and attempting to modify the tourism industry itself. [ABSTRACT FROM AUTHOR]

The ageing effect in the life-cycle assessment should be considered for the high-strength steel structures constructed in corrosive environments and high-seismicity zones. Additionally, the structures can suffer multi-dimensional seismic excitations because of the spatial effect of ground motions. Therefore, this study aims to investigate the impact of different loading protocols on the mechanical properties of Q690 steel columns with H-section during the whole life-cycle. Firstly, numerical methods considering time-varying corrosion process are used to simulate the ageing steel columns. After that, the nonlinear hysteretic behaviors of the ageing steel columns under different loading protocols are investigated. The factor of resistance degradation (the degree of degradation of ultimate resistance) is employed to quantify the effect of loading protocols on ageing steel columns. Finally, the biaxial ultimate interaction curve considering the ageing effect and a practical design process are proposed. The findings demonstrate that the steel columns exhibit different mechanical properties under various loading protocols, and the coupling direction of bi-directional displacement loads influences the degree of degradation of ultimate resistance. As service time increases, the factor of resistance degradation of steel columns gradually reduces by up to 40%. The proposed biaxial ultimate interaction curve has acceptable accuracy. These findings emphasize the importance of employing the unfavorable loading protocols in conducting the seismic design of the steel columns in different life-cycle stages. • The numerical simulation method of steel columns considering the time-varying characteristics of corrosion is established. • The mechanical properties of ageing steel columns under different cyclic loading protocols are analyzed. • The biaxial ultimate interaction curves of steel columns during whole life-cycle is proposed. [ABSTRACT FROM AUTHOR]

Pest control is easier and more effective when pests are correctly identified. The Black Parlatoria Scale, Parlatoria ziziphi (Lucas, 1853) (Hemiptera: Coccomorpha: Diaspididae) is an important invasive pest in citrus-growing countries. This diaspidid has historically been difficult to control, because its immature stages are difficult to identify due to confusion with similar Parlatoria species. No field descriptions of female or male developmental stages are available for P. ziziphi. We provide the first description of field characteristics of the developmental stages of P. ziziphi. Colonies were reared in the laboratory on sour orange plants and lemon fruits to illustrate the distinctive features of each instar. An illustrated field guide of all life-cycle stages of male and female P. ziziphi is provided for correct species identification and better pest management. This tool is designed to help recognize P. ziziphi in field-scouting programmes or quarantine inspections, without the need for taxonomic expertise in identifying the Parlatoria group. [ABSTRACT FROM AUTHOR]

This paper aims to present the effect of life cycle on financial reporting quality (FRQ). Discretionary accruals, small profit, and audit aggressiveness were used to test the FRQ from different approaches for Borsa Istanbul-listed companies between 2008 and 2017. The sample comprises 1,645 observations of 217 companies over a 9 year period. The life stages were estimated with Dickinson’s cash-flow patterns. Following Hansen, Hong and Park⁠, introduction, growth, mature, shake-out, and decline parameters were assigned values of 0, 0.25, 0.5, 0.75, and 1, respectively. The findings for small profit and discretionary accruals are consistent with those of previous literature. Results show that both discretionary accruals and small profit decrease as the companies move forward in their life cycles, while, on the other hand, audit aggressiveness increases. A negative coefficient was observed, but it was insignificant for the other dependent variables. The findings provide insight into the effect of life-cycle stages on FRQ. Results show that the introduction and decline stages negatively affect FRQ, and in addition showed that the audit aggressiveness of Turkish companies decreases with increased listing duration.

The household life-cycle stage is a significant contributor to the perception of subjective well-being; however, the effect of household expenditures of life-cycles on subjective well-being has not been thoroughly explored. The life-course perspective, specifically the study of family/household life-cycles, emphasizes the understanding of subjective well-being across the entire life-span. Accordingly, in the literature subjective well-being is often studied at different life-stages considering the influence of variables such as age, cohabitation and fertility. The present study evaluates the level of subjective well-being across the various life-cycle stages using a matching method on a Hungarian national sample. This approach is appropriate for studies using observational data because the administration of a true experimental design is usually not feasible for this type of research. The main finding of the article is that controlling for the expenditure structure significantly modifies the effect of life-cycle on subjective well-being, which is varied across life-cycle stages and shown to be highly dependent on household expenditures. [ABSTRACT FROM AUTHOR]

The purpose of the research is to determine the effect of auditor industry specialization and auditor tenure on comparability of financial statements by emphasis on the firm's life cycle. In this research, the comparability of financial statements was measured by De Franco (2011) model, auditor industry specialization was measured by Krishnan (2003) model and auditor tenure was measured using the numbers of continuous years offering audit services by an auditor. Target sample consists of 112 companies listed in Tehran Stock Exchange during 2009-2015. Hypotheses were examined using regression analysis. Results showed that auditor industry specialization has a positive and significant effect on comparability of financial statements in general and in the maturity stage. Also, auditor tenure has no effect on comparability of financial statements in general and in different stages of firm's life cycle. [ABSTRACT FROM AUTHOR]

Instead of implementing each element individually, engineers must be aware of multiple interactions among all major value creation factors and their life-cycle stages. Interactions are analyzed by a set of factors and hierarchical levels within a production system based on empirical observations and described in analytical models. Such analyses and missing information about the current condition of the system and its parts remain limited to addressing specific aspects of interactions among factors and stages for multiple decision making. To build a case-based scope addressing the interactions among a set of factors and life-cycle stages, a comprehensive approach for mapping and integrating relevant elements of sustainable manufacturing is proposed in this paper. By applying the approach, a case study demonstrates how to integrate different levels of factors into various life-cycle stages in order to monitor their condition and provide necessary information for maintenance activities in a service provider company. [ABSTRACT FROM AUTHOR]

Recycling and recovery of materials from used products is one of the major avenues to reduce material throughput. Ideally, all materials are anticipated for being reused by the economy an infinite number of times. In reality, recovery of secondary materials may be difficult because of high costs, or because of degraded quality compared with virgin materials. The search for potential reduction of throughput in material cycles should be based on a knowledge of the limits to repeated cycles. To gain understanding of recycling limits, we developed a method to estimate the actual reduction potential for each throughput in a material's multi-cycle life. First, we investigated the material flow system of paper in Taiwan, and developed a supply chain network of paper flows. Systematic elaboration of the flows revealed where paper can be recycled and where paper can be lost. Second, we estimated the reduction potential with a material input–output Markov chain model, which maps the distribution and loss of materials on the supply chain processes. The model estimated the quantities and the life pathways of recycled materials across continuous life-cycles. An indicator was used to quantify the total performance of the material across repeated life-cycles. This method offers an opportunity to examine practices that approach the limit of reduction. This case study shows that the use and separation of paper waste after discarding may need to be reformed to extend the life-cycles of the material. [ABSTRACT FROM AUTHOR]

A combined increase in seawater [CO2] and [H+] was recently shown to induce a shift from photosynthetic HCO3− to CO2 uptake in Emiliania huxleyi. This shift occurred within minutes, whereas acclimation to ocean acidification (OA) did not affect the carbon source., To identify the driver of this shift, we exposed low- and high-light acclimated E. huxleyi to a matrix of two levels of dissolved inorganic carbon (1400, 2800 μmol kg−1) and pH (8.15, 7.85) and directly measured cellular O2, CO2 and HCO3− fluxes under these conditions., Exposure to increased [CO2] had little effect on the photosynthetic fluxes, whereas increased [H+] led to a significant decline in HCO3− uptake. Low-light acclimated cells overcompensated for the inhibition of HCO3− uptake by increasing CO2 uptake. High-light acclimated cells, relying on higher proportions of HCO3− uptake, could not increase CO2 uptake and photosynthetic O2 evolution consequently became carbon-limited., These regulations indicate that OA responses in photosynthesis are caused by [H+] rather than by [CO2]. The impaired HCO3− uptake also provides a mechanistic explanation for lowered calcification under OA. Moreover, it explains the OA-dependent decrease in photosynthesis observed in high-light grown phytoplankton. [ABSTRACT FROM AUTHOR]

Background: The moon jellyfish Aurelia aurita is a widespread scyphozoan species that forms large seasonal blooms. Here we provide the first comprehensive view of the entire complex life of the Aurelia Red Sea strain by employing transcriptomic profiling of each stage from planula to mature medusa. Results: A de novo transcriptome was assembled from Illumina RNA-Seq data generated from six stages throughout the Aurelia life cycle. Transcript expression profiling yielded clusters of annotated transcripts with functions related to each specific life-cycle stage. Free-swimming planulae were found highly enriched for functions related to cilia and microtubules, and the drastic morphogenetic process undergone by the planula while establishing the future body of the polyp may be mediated by specifically expressed Wnt ligands. Specific transcripts related to sensory functions were found in the strobila and the ephyra, whereas extracellular matrix functions were enriched in the medusa due to high expression of transcripts such as collagen, fibrillin and laminin, presumably involved in mesoglea development. The CL390-like gene, suggested to act as a strobilation hormone, was also highly expressed in the advanced strobila of the Red Sea species, and in the medusa stage we identified betaine-homocysteine methyltransferase, an enzyme that may play an important part in maintaining equilibrium of the medusa's bell. Finally, we identified the transcription factors participating in the Aurelia life-cycle and found that 70% of these 487 identified transcription factors were expressed in a developmental-stage-specific manner. Conclusions: This study provides the first scyphozoan transcriptome covering the entire developmental trajectory of the life cycle of Aurelia. It highlights the importance of numerous stage-specific transcription factors in driving morphological and functional changes throughout this complex metamorphosis, and is expected to be a valuable resource to the community. [ABSTRACT FROM AUTHOR]

In fragmented landscapes, the sharp transitions between remnant habitats and those created by human disturbances result in 'edge effects'. Changes in microhabitat characteristics (for example, the height at which epiphytic plants grow on their host trees) may, however, modulate these effects. We evaluated how distance to the edge and height on the host tree affect seed germination and adult occurrence of the austral-forest epiphyte Sarmienta repens. The negative effect of edges on germination and adult occurrence was modulated by a vertical gradient (height) with contrasting effects on seed germination and survival to adulthood. Seed germination was affected by both height and distance to the forest edge, increasing away from forest edges for plants growing on trees in mid-story (3-6 m) and canopy zones (6-12 m) but being unaffected by the distance to the edge for plants located in understory zones (<3 m above the ground). Adult occurrence, in contrast, increased with both height and distance to the edge. As a result, seeds deposited near edges germinated best at a microhabitat (understory zone) inadequate for subsequent survival. Our results stress the importance of maintaining intact forest areas, free from edge influences and hosting large trees, to preserve the rich epiphytic flora characteristic of humid forests. [ABSTRACT FROM AUTHOR]

Several species of Dinophysis Ehrenb. have been observed to produce “small cells” that are different in size and shape from the vegetative cells, following a reductionary division under certain environmental conditions, as part of a polymorphic life cycle. Based on observations on fixed field samples, D. diegensis Kof. was hypothesized to be a small form of D. caudata Saville-Kent. In this study, this hypothesis was confirmed after incubations, in cell culture chambers, of groups of individually picked vegetative cells from natural populations of D. caudata. Eight to 10 d after inoculation, different life-cycle stages were observed in the wells. Illustrations of small and intermediate forms of D. caudata developed in vitro were contrasted with those observed during their proliferation in the northeast Atlantic (Galicia) and northwest Mediterranean (Catalonia) coasts of Iberia. It is proposed that Dinophysis diegensis–like specimens should be considered as a taxonomic (or heterotypic) synonym of Dinophysis caudata. A historical overview is provided (see Supplementary material) that revises the large list of taxa used to nominate different morphotypes of D. caudata, and its small and intermediate cells, since its original description by Saville-Kent in 1881. [ABSTRACT FROM AUTHOR]

Using the 1998 Survey of Consumer Finances (SCF), this study examined factors related to two types of consumer debt: installment debt and credit card debt. To address the limitations of the conventional life-cycle hypothesis, the study incorporated ability, willingness, and need to borrow, and prudence as well as lifecycle stages in the conceptual framework. The results of the double-hurdle model showed that life-cycle stages, willingness and ability to borrow, prudence, and the need to borrow were significant factors affecting installment debt and credit card debt. Based on the results, implications for financial counselors and educators, lenders, consumers, and policy makers are discussed. [ABSTRACT FROM AUTHOR]

Recent studies have used transition matrix elasticity analysis to investigate the relative role of survival (L), growth (G) and fecundity (F) in determining the estimated rate of population increase for perennial plants. The relative importance of these three variables has then been used as a framework for comparing patterns of plant life history in a triangular parameter space. Here we analyse the ways in which the number of life-cycle stages chosen to describe a species (transition matrix dimensionality) might influence the interpretation of such comparisons. Because transition matrix elements describing survival ('stasis') and growth are not independent, the number of stages used to describe a species influences their relative contribution to the population growth rate. Reduction in the number of stages increases the apparent importance of stasis relative to growth, since each becomes broader and fewer individuals make the transition to the next stage per unit time period. Analysis of a test matrix for a hypothetical tree species divided into 4-32 life-cycle stages confirms this. If the number of stages were defined in relation to species longevity so that mean residence time in each stage were approximately constant, then the elasticity of G would reflect the importance of relative growth rate to λ. An alternative, and simpler, approach to ensure comparability of results between species may be to use the same number of stages regardless of species longevity. Published studies for both herbaceous and woody species have tended to use relatively few stages to describe life cycles (herbs: n=45, $$\bar x = 6.16 \pm 4.63$$ ; woody plants: n=21, $$\bar x = 8.38 \pm 3.57$$ ) and so approximate this approach. By using the same number of stages regardless of longevities, the position of species along the G-L side of the triangular parameter space largely reflects differences in longevity. The extent of variation in elasticity for L, G and F within and between species may also be related to factors such as successional status and habitat. For example, the shade-tolerant woody species, Araucaria cunninghamii, shows greater importance for stasis (L), while the gap-phase congener species, Araucaria hunsteinii, shows higher values for G (although values are likely to vary with the stage of stand development). [ABSTRACT FROM AUTHOR]

Birds show quite distinct changes in both external and internal appearance. An evolutionary interpretation of these cyclic life-history phenomena would benefit from a system of description aimed at mapping shared ancestries of arguably the "easiest" of traits: the molts and seasonal plumage changes. By 1959, Humphrey and Parkes had already provided the basis of such a system, but its development and application, especially with regard to the confusing first plumage cycle, by Howell et al. (2003), adds considerably to its power. I hope this leads to an upsurge of evolutionary studies of molt and plumage cycles that in turn provide the basis for analyses of other aspects of the flexible phenotype of birds. With such an increase, the study of molts and plumages could once again be at center stage of avian biology. [ABSTRACT FROM AUTHOR]

Coccolithophores, especially the abundant, cosmopolitan species Emiliania huxleyi (Lohmann) W. W. Hay et H. P. Mohler, are one of the main driving forces of the oceanic carbonate pump and contribute significantly to global carbon cycling, due to their ability to calcify. A recent study indicates that termination of diploid blooms by viral infection induces life-cycle transition, and speculation has arisen about the role of the haploid, noncalcifying stage in coccolithophore ecology. To explore gene expression patterns in both life-cycle stages, haploid and diploid cells of E. huxleyi (RCC 1217 and RCC 1216) were acclimated to limiting and saturating photon flux densities. Transcriptome analyses were performed to assess differential genomic expression related to different ploidy levels and acclimation light intensities. Analyses indicated that life-cycle stages exhibit different properties of regulating genome expression (e.g., pronounced gene activation and gene silencing in the diploid stage), proteome maintenance (e.g., increased turnover of proteins in the haploid stage), as well as metabolic processing (e.g., pronounced primary metabolism and motility in the haploid stage and calcification in the diploid stage). Furthermore, higher abundances of transcripts related to endocytotic and digestive machinery were observed in the diploid stage. A qualitative feeding experiment indicated that both life-cycle stages are capable of particle uptake (0.5 μm diameter) in late-stationary growth phase. Results showed that the two life-cycle stages represent functionally distinct entities that are evolutionarily shaped to thrive in the environment they typically inhabit., (© 2011 Phycological Society of America.)