Germination of the Spores and Development of Primary and Secondary Protonema of Funaria hygrometrica

Abstract

1. The primary protonema of Funaria hygrometrica, cultivated on Knop's or Marchal's agar in the light, proved to consist of filaments with much chlorophyll, a hyaline membrane, perpendicular cross-walls and branches equal to the main filament (chloronema). These filaments grow on the surface of the agar, the branches may also grow vertically. Sometimes filaments with less chlorophyll occur immediately after the germination. The caulonema described by Sironval has not been observed. Thus the rhizoid-like forms mentioned in the literature should more likely be considered as a result of external conditions (see Schoene, Bauer, Heitz and Fitting). Therefore it remains doubtful if a distinction between rhizoids and chloronema on the primary protonema is of any importance as it is impossible to give a good definition of either form.

At the base of moss plants main filaments with brown membranes, oblique septa and without chlorophyll may develop (rhizoids). They grow on the surface or within the agar. In F. hygrometrica especially, the stem seems to influence the occurrence of these rhizoids. The main filaments form buds on the basal cell of the branches and thus serve for vegetative reproduction. The branches show the characteristics of the chloronema. This is contrary to the conclusion of Westerdijk that rhizoids would pass into chloronema only when they are damaged or when the growth of the end bud of the plant is inhibited. At the base of the plant, moreover, little ramified, short branches with oblique septa appear which do not produce buds.

2. Branches may develop in the first growth stages of the primary protonema at any point of the cells. One single cell of a main filament can produce none, one, or more than one branch. Later the branches appear immediately behind the acroscopic cross-wall except in a few cases. Each cell then produces one branch.

3. Buds always develop at the basal cell of a primary branch of a green main filament or of a rhizoid derived from a moss plant.

4. In two ways the protonema may fall into pieces, which can develop into new main filaments:

(a) By forming brood cells; rounded cells which get detached by splitting of the septum. This phenomenon is very frequent. Contrary to Servettaz's opinion it seems to occur particularly under unfavourable conditions.

(b) By forming special cells, tmemata, whose walls are rent. These occur on the primary protonema contrary to the observations of Correns and Bauer, but they are much less frequent than the brood cells. No observations have been made on the circumstances of their occurrence.     

Estimating Attributable Life Expectancy Under the Proportional Mean Residual Life Model

In population-based health research, the so-called population attributable fraction is an important quantity that calculates the percentage of excess risk of morbidity and mortality associated with modifiable risk factors for a given population. While the concept of “risk” is usually measured by event probabilities, in practice it may be of a more direct interest to know the excess life expectancy associated with the modifiable risk factors instead, particularly when mortality is of the ultimate concern. In this paper, we thus propose to study a novel quantity, termed “attributable life expectancy,” to measure the population attributable fraction of life expectancy. We further develop a model-based approach for the attributable life expectancy under the Oakes–Dasu proportional mean residual life model, and establish its asymptotic properties for inferences. Numerical studies that include Monte-Carlo simulations and an actual analysis of the mortality associated with smoking cessation in an Asia Cohort Consortium are conducted to evaluate the performance of our proposed method.

     

Prospective sustainability assessment: the case of wood in automotive applications

Purpose

The introduction of renewable materials into automotive applications is perceived as an innovative lightweight solution. Wood-based materials are advantageous in that they have potentially lower environmental impacts as compared with other materials such as steel. However, using wood per se does not automatically ensure more sustainability. Few prospective sustainability assessment methods or studies on the use of wood-based materials in automotive applications have been carried out, although these are needed to reduce unintended, negative sustainability effects and to support sustainable oriented research and innovation. Therefore, this study was conducted to assess the potential sustainability effects and consequences of introducing a wood-based component into an automotive application.

Methods

A combination of methods was used to analyze the potential sustainability effects when introducing wood into automotive applications. This prospective life cycle sustainability analysis solely relied on secondary data. The environmental impacts were analyzed using a simplified environmental life cycle assessment on the product level. A multi-regional input-output-based assessment was conducted to model the country-specific environmental and socioeconomic consequences. The potential shift in social risks and opportunities on a national scale was analyzed by conducting a generic social life cycle assessment. Various aspects of each approach differ, with each providing a specific perspective of the system under study.

Results and discussion

The results indicate that implementing wood into automotive application can have environmental, social, and economic benefits, according to most of the indicators analyzed. Mostly due to the product weight reduction due to the use of a wood-based component, the results show that environmental impacts decrease. Some possible consequences of using wood-based materials are increased value added and increasing the number of jobs in European countries. Similarly, the social risks and opportunities are shifted from countries all over the world to European countries, which perform better than developing countries according to several indicators. However, some indicators, such as migrant acceptance or local supplier quantity, perform better in the current situation.

Conclusions

The presented case study is particularly notable, because the results clearly indicate the advantages of using wood-based materials in automotive applications, although the application of such relatively holistic and complex approaches often may lead to rather indifferent pictures. Policy makers, researchers, and companies can apply this combination of methods that rely solely on generic data to obtain both feasible and informative results. These methods also allow users to link the product level assessment with a regional and social perspective and screen critical topics to support sustainability research and innovation.

     

On the Virtues Of Simplicity:

Abstract

The assumption of complexity seems to dominate much of anthropological thinking. This is clearly indicated by the frequency of use of complex multivariate statistics such as factor analysis. It is argued here that human behavior may often be much simpler than assumed and that the optimal approach to data analysis is to assume simplicity until demonstrated otherwise. It is also argued that when multivariate statistics are used, they are most effectively used in a deductive framework.     

Using Ari Kara Osteological Data To Evaluate An Assumpti on oF Fur Trade Archaeology

Abstract

Osteological data from the Arikara-affiliated Mobridge site in South Dakota are used to test an hypothesis frequently expressed in archaeology that the relative quantity of recovered Euro-American goods can be used to infer a site? s relative age. Crania from the Mobridge site are examined for intra-site differences and thecompared with crania from four other sites. Our analysis suggests that the dating assumption may have validity for some archaeological sites, particularly those associated with the Arikara, and may even be valid on the intra-site level as demonstrated by our analysis of the Mobridge data     

No rest for the women: Understanding the impact of on-call work for women in the emergency services

ABSTRACT

Background: The unpredictable, “on-call” component of the emergency services (ES) may be difficult to navigate in the context of domestic and work responsibilities, and especially difficult for women, given they tend to take on a greater household burden than do men. Our aim was to understand women’s experiences in the ES, particularly the impact of being on-call and related coping strategies.

Methods: Twenty-four women were recruited from two ES agencies in Australia. Participation involved a brief questionnaire and a 45–60-min interview. Interviews were recorded, and audio files were transcribed before analysis using nVIVO software.

Results: Interview data identified two major themes: impact and management. Women talked about the impact of on-call for themselves (e.g. disturbed? sleep, fatigue and the relentlessness of the role) but also discussed the, largely negative, impact for their family/household. In terms of management, support (family, social and work) and planning and preparation were identified as important in helping women manage their multiple roles in the context of on-call unpredictability.

Conclusion: The negative impacts of on-call work on women’s sleep supports existing quantitative and qualitative data in the broader on-call area. For those women with children, managing their care presents one of the biggest challenges to being able to manage the on-call component of their work. Future research should to focus on quantifying the impact of on-call for both men and women, particularly the “relentlessness” of the work identified in this study and whether this toll changes based on other factors such as experience, role or gender.     

Exploring the potential of participatory systems thinking techniques in progressing SLCA

Purpose

There are a range of systems thinking-based methods well established for participatory actions that allow for greater integration of various mental models and understanding of systems that should be considered in advancing engagement methods in SLCA. This paper highlights the potential application of participatory modelling approaches based in systems thinking theory as a potential entry point in stakeholder inclusion and understanding impact pathways and system behaviour in social life cycle assessment (SLCA).

Methods

We discuss the application of various systems thinking methodologies to SLCA, along with pertinent examples from literature, and develop a framework that integrates both methodologies.

Results and discussion

Here we propose three distinct benefits of group modelling approaches; (1) procedural benefits through the ability to be inclusive of mental models, various perspectives and enhance stakeholder conceptualisation of a system; and the ability to combine both (2) qualitative and (3) quantitative analysis techniques under a cohesive framework. We propose the specific merits of combining the use of agent-based (AB) and system dynamic (SD) modelling in SLCA due to the emphasis upon consumer decisions and behaviour and the inherently dynamic non-linear cause-effect chains that are common in social systems.

Conclusions

We conclude that many facets of participatory modelling techniques can align with SLCA across the methodology, particularly if enhanced consideration of stakeholders and their various values is desired. We recommend the further development and inclusion of participatory systems thinking-based frameworks to advance the SLCA methodology with specific reference to the ability to enhance interpretation through the analysis of feedbacks that may not be addressed in current approaches.

     

On the number of Monte Carlo runs in comparative probabilistic LCA

Introduction

The Monte Carlo technique is widely used and recommended for including uncertainties LCA. Typically, 1000 or 10,000 runs are done, but a clear argument for that number is not available, and with the growing size of LCA databases, an excessively high number of runs may be a time-consuming thing. We therefore investigate if a large number of runs are useful, or if it might be unnecessary or even harmful.

Probability theory

We review the standard theory or probability distributions for describing stochastic variables, including the combination of different stochastic variables into a calculation. We also review the standard theory of inferential statistics for estimating a probability distribution, given a sample of values. For estimating the distribution of a function of probability distributions, two major techniques are available, analytical, applying probability theory and numerical, using Monte Carlo simulation. Because the analytical technique is often unavailable, the obvious way-out is Monte Carlo. However, we demonstrate and illustrate that it leads to overly precise conclusions on the values of estimated parameters, and to incorrect hypothesis tests.

Numerical illustration

We demonstrate the effect for two simple cases: one system in a stand-alone analysis and a comparative analysis of two alternative systems. Both cases illustrate that statistical hypotheses that should not be rejected in fact are rejected in a highly convincing way, thus pointing out a fundamental flaw.

Discussion and conclusions

Apart form the obvious recommendation to use larger samples for estimating input distributions, we suggest to restrict the number of Monte Carlo runs to a number not greater than the sample sizes used for the input parameters. As a final note, when the input parameters are not estimated using samples, but through a procedure, such as the popular pedigree approach, the Monte Carlo approach should not be used at all.

     

On the Quinacrine fluorescence and Giemsa staining patterns of the chromosomes of Vicia faba

Abstract

A comparison has been made between the Quinacrine fluorescence bands and the bands obtained with a denaturating-reannealing-Giemsa technique in Vicia faba. The results show that some of the bands, particularly on the M and, proximally, on the S chromosomes are visible with both techniques. A complex pattern of bands on the S chromosomes is revealed with the Giemsa technique. Both the similarities and the differences between the banding patterns obtained with the two methods in Vicia faba may indicate various degrees of DNA repetitiousness and other physico-chemical properties in the chromosome segments involved.     

Comparison of two versions of an EPD,using generic and specific data for the foreground system,and some methodological implications

Purpose

Differences in the practice of inclusion and the definition of specific and generic data when performing an LCA for an Environmental Product Declaration (EPD) may lead to incomparable EPDs. The purpose of this paper is to illuminate the importance of precise definitions regarding data quality in EPDs.

Method

The authors define relevant terminology before describing methodological differences between two versions of EPDs for an office chair. The analyses performed for one EPD use generic data for the foreground system, while the other uses specific data. Results for some impact categories as well as inventory findings are shown, and the reasons for differences are investigated and discussed.

Results

Relevant dilemmas are examined with regard to the choice of generic or specific data. These include practical hindrances and the promotion of environmental improvement. Some preliminary methodological and organisational implications are described, followed by an outline of further research.

Conclusions

This paper shows the substantial variations arising from using two datasets with different degrees of specificity, and concludes that they increase in relation to the distinctiveness of the process or material. This highlights the importance of EPD programmes in establishing precise, unambiguous definitions and vocabulary with regard to specific as against generic data, when combined with foreground and background processes. It is essential to take this into consideration so as to avoid misunderstandings or false agreement when discussing data quality. It is also necessary in order to avoid comparisons of products based on very different assumptions.

     

Studies on the role of RNA synthesis in auxin induction of cell enlargement

Selective inhibitors were used to study the connection between nucleic acid synthesis and indoleacetic acid (IAA) induction of cell enlargement. Actinomycin D (act D) and azaguanine (azaG) almost completely inhibit IAA-induced growth in aged artichoke tuber disks when they are added simultaneously with IAA. In contrast, when they are added 24 hours after the hormone, these inhibitors have little or no effect on the induced growth which continues for 48 hours or more with little or no inhibition. Inhibitors of protein synthesis still stop growth when applied 24 hours after the IAA, thus protein synthesis and presumably supporting metabolism are still essential.

In corn coleoptile sections auxin-induced growth did not show any pronounced tendency to become less sensitive to act D as the IAA treatment progressed. Act D did not completely inhibit the response to IAA unless the sections were pretreated with act D for 6 hours. In contrast to act D, cordycepin produced almost complete inhibition of IAA-induced growth when added with the IAA.

Although IAA has a very large and very rapid stimulatory effect (within 10 min) on incorporation of ³²P-orthophosphate into RNA in disks, it did not cause a detectable change in the base composition of the RNA synthesized. Furthermore, the promotive effect could be accounted for through increased uptake of the ³²P. That much of the RNA synthesis in these tissues is not necessary for auxin action is indicated by the results with fluorouracil (FU). FU strongly inhibits RNA synthesis, probably acting preferentially on ribosomal RNA synthesis, without inhibiting auxin-induced growth in the disks or coleoptile sections. FU also strongly inhibited respiration in auxin-treated disks indicating that the large promotion of respiration by auxin likewise may not be entirely necessary for growth.

At least in the artichoke disks, RNA synthesis is required for auxin induction of cell enlargement and not for cell enlargement itself.

The possible relationships of auxin induction of cell enlargement and RNA synthesis are discussed.

     

Environmental and techno-economic analyses of bio-jet fuel produced from jatropha and castor oilseeds in China

Purpose

Bio-jet fuel derived from energy crops has been promoted by governments around the world through policies such as the Carbon Offsetting and Reduction Scheme for International Aviation. The environmental impact and techno-economic analysis of bio-jet fuel are particularly pertinent to China because China is under huge pressure to reduce emissions, endeavouring to meet bio-economic goals.

Methods

An LCA study was conducted on the production of bio-jet fuel from jatropha and castor by estimating the well-to-wake emissions and its economic impact. The functional unit was 1 MJ of bio-jet fuel, and field survey data was used in inventory analysis. A scenario analysis was performed to measure diverse conditions, including the planting conditions, planting regions, allocation methods, and hydrogen sources. A techno-economic analysis that combined the production costs and co-product credits was performed to calculate the minimum bio-jet fuel selling price (MJSP) based on a plant capacity of 2400 metric tonnes of feedstock per day.

Results and discussion

Compared to the environmental impacts to the fossil jet fuel, the use of biofuel would reduce the majority environmental impacts by 36–85%, when a 1:1 displacement of fossil jet fuel is considered, though the human toxicity potential impact was 100% higher. The scenario analysis indicated that (i) planting castor in harsh and unevenly distributed conditions and jatropha in stable or fertile conditions can leverage their respective advantage; (ii) the global warming potential (GWP) from castor planting in the region of north-east China ranges from 34 to 48 g CO₂ eq/MJ; (iii) the GWP produced through the steam methane reforming process can be reduced by 16–17%, using advances in technological processes. The MJSP for fuel produced from jatropha and castor under the basic scenario is estimated to be 5.68 and 4.66 CNY/kg, respectively, which falls within the current market price range of 4.5–7.5 CNY/kg.

Conclusions

Bio-jet fuel from jatropha and castor oilseeds offers potential environmental benefits if they can reduce fossil jet fuel on an energy-equivalent basis. However, these benefits are likely to be reduced by the rebound effect of the fuel market. Future research is needed to better understand the magnitude of the rebound effect in China and what policy interventions can be implemented to alleviate it. Scenario analysis demonstrated the feasibility and potential of bio-jet fuel development from multiple perspectives and technological progress are conducive to the realization of environmental protection policies.

     

Life: Self-Directing with Unlimited Variability on Self-Speeding

Abstract

The crystal structure of the deoxyoctamer d(G-G-^Br U-A-^BrU-A-C-C) was refined to a resolution of 1.7Å using combined diffractometer and synchrotron data. The analysis was carried out independently in two laboratories using different procedures. Although the final results are identical the comparison of the two approaches highlights potential problems in the refinement of oligonucleotides when only limited data are available.

As part of the analysis the positions of 84 solvent molecules in the asymmetric unit were established. The DNA molecule is highly solvated, particularly the phosphate-sugar backbone and the functional groups of the bases. The major groove contains, in the central ^BrU-A-^BrU-A region, a ribbon of water molecules forming closed pentagons with shared edges. These water molecules are linked to the base O and N atoms and to the solvent chains connecting the O-1 phosphate oxygen atoms on each strand. The minor groove is also extensively hydrated with a continuous network in the central region and other networks at each end. The pattern of hydration is briefly compared with that observed in the crystal structure of a B-dodecamer.     

Investigation on the Physiological Ecology of Tortula ruraliformis

Abstract

1. Tortula ruraliformis is a xerophyte whose structura1 and physiological features suit it to an environment subject to cosiderable desiccation and sand movement

2. Untwisting and expansion of the leaves depend on hygroscopic movements but turgor phenomena may also be concerned.

3. The moss is poikilobydrous, its water content quickly equilibrating with the environment. The leaves unfold at relative humidities pater than 90 %.

4. The tops of the shoots are physiologically the most active. Analyses of the chief constituents (carbohydrates, nitrogen compounds. ash) have been made.

5. Sucrose is the most important photosynthetic product, making up usually S % or more of the dry weight of the plant. Starch is absent from the leaves, and most of the hexose is glucose.

6. Photosynthesis virtually ceases when the leaves are tightly rolled inwards round the stem.

7. On re-hydration of moderately drougbted shoots, the respiration rate rises quickly from a very low value, and the tissues can photosynthesize immediately.

8. After very prolonged desiccetion, photosynthetic power is impaired, and the respiration rises to a peak rate some appreciable time after re-hydration and then declines.     

A social panorama within the life cycle thinking and the circular economy: a literature review

Purpose

This literature review aims to present the current methodologies that have been developed to perform a social life cycle assessment (sLCA) and to display the main differences among them. In addition to that, to identify the nexus between sLCA and circular economy (CE) and to what extent this life cycle technique has been involved within CE studies.

Methods

An analysis of scientific literature using online databases was made. A total of 76 publications, including all industry sectors worldwide, were chosen spanning 11 years, from 2009 to 2020. Special attention was made to the methodology used to assess the social impacts, the impact categories analyzed, and whether there is or not a circular economy case. All the impact categories of both UNEP/SETAC and PSIA were taken into account when doing the review, and the top three of the categories are mentioned here.

Results and discussion

The leadership of the UNEP/SETAC methodology is clear with 58 cases. Almost 90% of the case studies are focused on products while the remaining ones are related with services. Workers are the most considered stakeholder when conducting an sLCA research, followed by local communities and society. Regarding the impact assessment, the performance reference point (PRP) was the most common method used. When considering the CE even when some cases included the end-of-life stage in the system boundaries, the studies did not consider the actors from that stage; excluding these cases, one out of four articles has a link with CE, a promising proportion taking into account the early stage of both concepts (i.e., sLCA and CE).

Conclusions

UNEP/SETAC guidelines seem to be the most promising methodology due to its reception among the scientific community. However, a more industry-oriented approach is proposed by the Roundtable for Product Social Metrics (PSIA) in a way to respond to manufacturing companies’ demand. Regardless of the type of methodology to be implemented, workers represent the key stakeholder when assessing social impacts. The change in usual patterns is leading to a change in the way how stakeholders interact and therefore new and more impacts may arise, and that is the reason why it is important to include the CE into the sLCA. A series of challenges such as the feasibility of aggregating all the life cycle techniques to one (life cycle sustainability assessment), data availability, and quality are still present for the moment.

     

Studies on the Biosynthesis of Streptomycin

Myo-inositol, especially in combination with arginine, enhances streptomycin production. Compounds which show structural relationship with myo-inositol are ineffective.

Myo-inositol decreases the incorporation of C¹⁴-glucose into streptomycin, particularly into streptidine. This effect suggests that myo-inositol is a precursor of the streptidine ring.

Methionine stimulates antibiotic production in a synthetic medium but proves to be unfavorable in a complex medium.

The γ- and δ-isomers of hexachlorocyclohexane inhibit streptomycin formation.

The formation of streptomycin by washed mycelium was studied. Essentially the same results were here obtained as with growing cultures.

     

Effect of methodological choice on the estimated impacts of wool production and the significance for LCA-based rating systems

Purpose

One aim of LCA-based rating tools developed by the apparel industry is to promote a change in demand for textiles by influencing consumer preferences based on the environmental footprint of textiles. Despite a growing consensus that footprints developed using attributional LCA (aLCA) are not suitable to inform decisions that will impact supply and demand, these tools continue to use aLCA. This paper analyses the application of the LCA methods to wool production, specifically the application of aLCA methods that provide a retrospective assessment of impacts and consequential (cLCA) methods that estimate the impacts of a change.

Methods

Attributional and consequential life cycle inventories (LCIs) were developed and analysed to examine how the different methodological approaches affect the estimated environmental impacts of wool.

Results and discussion

Life cycle impact assessment (LCIA) of aLCI and cLCI for wool indicates that estimated global warming and water stress impacts may be considerably lower for additional production of wool, as estimated by cLCIA, than for current production as estimated by aLCIA. However, fossil resource impacts for additional production may be greater than for current production when increased wool production was assumed to displace dedicated sheep meat production.

Conclusions

This work supports the notion that the use of a retrospective assessment method (i.e. aLCA) to produce information that will guide consumer preferences may not adequately represent the impacts of a consumer’s choice because the difference between aLCIA and cLCIA results may be relatively large. As such, rating tools based on attributional LCA are unlikely to be an adequate indicator of the sustainability of textiles used in the apparel industry.