On the use of ordinal scoring scales in social life cycle assessment

The International Journal of Life Cycle Assessment -     

The double life of Irs

The liver plays a central role in lipid and glucose metabolism. Two studies in this issue (Kubota et al., 2008; Dong et al., 2008) on the insulin-signaling adaptors Irs1 and Irs2 prompt a critical reappraisal of the physiology of fasting and of the integrated control of hepatic insulin action.     

The double life of ribosomal proteins

Many integral proteins of the ribosome also carry out extra-ribosomal functions as independent polypeptides, raising questions as to their evolutionary derivation. In this issue of Cell, Mazumder et al. report a surprising new twist in the dual life of these molecules: as part of a cellular response to interferon, a large-subunit protein dramatically exits the ribosome to bind and inhibit the translation of a specific mRNA.     

Addressing the effect of social life cycle assessments

Purpose

In the recently published ??Guidelines for social life cycle assessment of products??, it is stated that the ultimate objective of developing the social life cycle assessment (SLCA) is to promote improvements of social conditions for the stakeholders in the life cycle. This article addresses how the SLCA should be developed so that its use promotes these improvements.

Methods

Hypotheses of how the use of SLCA can promote improvement of social conditions in the life cycle are formulated, after which theories and empirical findings from relevant fields of research are used to address the validity of these hypotheses.

Results

Three in some cases potentially overlapping SLCA approaches are presented, assumed to create a beneficial effect in the life cycle in different ways. However, empirical and theoretical findings show that the beneficial effects proposed to arise from the use of each of these three approaches may all be problematic. Some of these problems may be mitigated through methodological modifications.

Conclusions

Given the significant problems in relation to creating an effect through the use of the SLCAs, and given the significant practical problems in applying the SLCAs, it is questioned whether the development of SLCA is a fruitful approach for improving social conditions in the product life cycle.     

The double life of a bacterial lipoprotein

It has been known for many years that the small lipoprotein Lpp, which is the most abundant protein in E. coli, exists in two forms. The 'bound' form of the protein is tethered to the outer membrane (OM) by its N-terminal lipid moiety and covalently attached to the cell wall by its C-terminal lysine residue. The exact location of the 'free' form, however, has never been determined. In this issue of Molecular Microbiology, Cowles et al. demonstrate that the free form of Lpp is an integral OM protein whose C-terminus is exposed on the cell surface. The new study provides the first example of a lipoprotein that has a dual localization and adds to a growing body of evidence that lipoproteins can span the OM despite the lack of an obvious transmembrane segment. Furthermore, the new results raise intriguing questions about the assembly of both lipoproteins and other types of OM proteins.     

The social life of ribosomal proteins

Ribosomal proteins hold a unique position in biology because their function is so closely tied to the large rRNAs of the ribosomes in all kingdoms of life. Following the determination of the complete crystal structures of both the large and small ribosomal subunits from bacteria, the functional role of the proteins has often been overlooked when focusing on rRNAs as the catalysts of translation. In this review we highlight some of the many known and important functions of ribosomal proteins, both during translation on the ribosome and in a wider context.     

Defining the baseline in social life cycle assessment

Background, aim and scope  

A relatively broad consensus has formed that the purpose of developing and using the social life cycle assessment (SLCA) is to improve the social conditions for the stakeholders affected by the assessed product’s life cycle. To create this effect, the SLCA, among other things, needs to provide valid assessments of the consequence of the decision that it is to support. The consequence of a decision to implement a life cycle of a product can be seen as the difference between the decision being implemented and ‘non-implemented’ product life cycle. This difference can to some extent be found using the consequential environmental life cycle assessment (ELCA) methodology to identify the processes that change as a consequence of the decision. However, if social impacts are understood as certain changes in the lives of the stakeholders, then social impacts are not only related to product life cycles, meaning that by only assessing impacts related to the processes that change as a consequence of a decision, not all changes in the life situations of the stakeholders will be captured by an assessment following the consequential ELCA methodology. This article seeks to identify these impacts relating to the non-implemented product life cycle and establish indicators for their assessment.     

The double life of CRISPR–Cas13

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On the origin of life

On the basis of the recently proposed new fundamental equation of mathematical biophysics, a suggestion is made for a theory of the formation of a primitive cell from nonliving material. The discussion includes a suggestion for a quantitative formulation of the degree of biological organization. It is shown that according to the fundamental equation of mathematical biophysics, organization of the nonliving material may spontaneously increase under certain conditions, leading to a formation of a primitive organism. This process however, is a very slow one, requiring time intervals of several years or even decades. This may account for the failure in observing or artificially producing spontaneous generation.     

Methodologies for social life cycle assessment

Goal, Scope and Background  

In recent years several different approaches towards Social Life Cycle Assessment (SLCA) have been developed. The purpose of this review is to compare these approaches in order to highlight methodological differences and general shortcomings. SLCA has several similarities with other social assessment tools, although, in order to limit the expanse of the review, only claims to address social impacts from an LCA-like framework are considered.     

The early life social environment and DNA methylation: DNA methylation mediating the long-term impact of social environments early in life

Although epidemiological data provides evidence that there is an interaction between genetics (nature) and the social and physical environments (nurture) in human development; the main open question remains the mechanism. The pattern of distribution of methyl groups in DNA is different from cell-type to cell type and is conferring cell specific identity on DNA during cellular differentiation and organogenesis. This is an innate and highly programmed process. However, recent data suggests that DNA methylation is not only involved in cellular differentiation but that it is also involved in modulation of genome function in response to signals from the physical, biological and social environments. We propose that modulation of DNA methylation in response to environmental cues early in life serves as a mechanism of life-long genome “adaptation” that molecularly embeds the early experiences of a child (“nurture”) in the genome (“nature”). There is an emerging line of data supporting this hypothesis in rodents, non-human primates and humans that will be reviewed here. However, several critical questions remain including the identification of mechanisms that transmit the signals from the social environment to the DNA methylation/demethylation enzymes.Key words: DNA methylation, psychiatry, development, epidemiology, environment