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OVERVIEW: Just as treatment guidelines for diabetes care were at the forefront of medical guideline development, (1) diabetes has been a prominent focus of performance measurement and quality improvement initiatives [...]

Product design is one of the most important sectors influencing global sustainability, as almost all the products consumed by people are outputs of the product development process. In particular, early design decisions can have a very significant impact on sustainability. These decisions not only relate to material and manufacturing choices but have a far-reaching effect on the product's entire life cycle, including transportation, distribution, and end-of-life logistics. However, key challenges have to be overcome to enable eco-design methods to be applicable in early design stages. Lack of information models, semantic interoperability, methods to influence eco-design thinking in early stages, measurement science and uncertainty models in eco-decisions, and ability to balance business decisions and eco-design methodology are serious impediments to realizing sustainable products and services. Therefore, integrating downstream life cycle data into eco-design tools is essential to achieving true sustainable product development. Our review gives an overview of related research and positions early eco-design tools and decision support as a key strategy for the future. By merging sustainable thinking into traditional design methods, this review provides a framework for ongoing research, as well as encourages research collaborations among the various communities interested in sustainable product realization. [DOI: 10.1115/1.4002308] Keywords: sustainable design, eco-design, product design, manufacturing, supply chain

At some stage in the origin of life, an informational polymer must have arisen by purely chemical means. According to one version of the 'RNA world' hypothesis (1-3) this polymer was RNA, but attempts to provide experimental support for this have fade (4,5). In particular, although there has been some success demonstrating that 'activated' ribonucleotides can polymerize to form RNA (6,7), it is far from obvious how such ribonucleotides could have formed from their constituent parts (ribose and nucleobases). Ribose is difficult to form selectively (8,9) and the addition of nucleobases to ribose is inefficient in the case of purines (10) and does not occur at all in the case of the canonical pyrimidines (11). Here we show that activated pyrimidine ribonucleotides can be formed in a short sequence that bypasses free ribose and the nucleobases, and instead proceeds through arabinose amino-oxazoline and anhydronucleoside intermediates. The starting materials for the synthesis--cyanamide, cyanoacetylene, glycolaldehyde, glyceraldehyde and inorganic phosphate--are plausible prebiotic feedstock molecules (12-15), and the conditions of the synthesis are consistent with potential early-Earth geochemical models. Although inorganic phosphate is only incorporated into the nucleotides at a late stage of the sequence, its presence from the start is essential as it controls three reactions in the earlier stages by acting as a general acid/base catalyst, a nucleophilic catalyst, a pH buffer and a chemical buffer. For prebiotic reaction sequences, our results highlight the importance of working with mixed chemical systems in which reactants for a particular reaction step can also control other steps., Because they comprise phosphate, ribose and nucleobases, it is tempting to assume that ribonucleotides must have prebiotically assembled from such building blocks. Thus, for example, it has previously been supposed [...]

The environmental performance of machining processes is of extreme importance in the field of sustainable manufacturing. The development of an environmental impact assessment method is a crucial strategy to realize energy and material efficient manufacturing, yet few studies have addressed energy and material flows using a common perspective. In principle, to realize the minimum environmental impact, energy and material flows must be viewed using the same metric; this is required to avoid impact shifting from energy to material or vice versa. In this paper, an environmental evaluation method for milling tool path strategies is proposed to support intelligent manufacturing, which considers energy flow (electricity provided to the machine tool and air compressor) and material flows (associated with the cutting tool, workpiece, and cutting fluid) for a milling process. The proposed method provides a quantitative calculation to characterize the total exergy loss in terms of energy and material flows. It is envisioned that total exergy loss can support quantitative decisions related to electricity consumption, tool wear, metal chips recycling, and cutting fluid loss. To demonstrate the applicability of the method, a case study is considered in which a milling tool path is selected to minimize exergy loss. The proposed method will be integrated into an intelligent control system for evaluating the total exergy loss of a milling process, which can assist manufacturers to make reliable decisions to reduce the environmental impact during machining stage in the industry 4.0 era. [ABSTRACT FROM AUTHOR]

Biological systems are homochiral, raising the question of how a racemic mixture of prebiotically synthesized biomolecules could attain a homochiral state at the network level. Based on our recent results, we aim to address a related question of how chiral information might have flowed in a prebiotic network. Utilizing the crystallization properties of the central ribonucleic acid (RNA) precursor known as ribose-aminooxazoline (RAO), we showed that its homochiral crystals can be obtained from its fully racemic solution on a magnetic mineral surface due to the chiral-induced spin selectivity (CISS) effect [Ozturk et al., arXiv:2303.01394 (2023)]. Moreover, we uncovered a mechanism facilitated by the CISS effect through which chiral molecules, such as RAO, can uniformly magnetize such surfaces in a variety of planetary environments in a persistent manner [Ozturk et al., arXiv:2304.09095 (2023)]. All this is very tantalizing because recent experiments with tRNA analogs demonstrate high stereoselectivity in the attachment of L-amino acids to D-ribonucleotides, enabling the transfer of homochirality from RNA to peptides [Wu et al., J. Am. Chem. Soc. 143, 11836 (2021)]. Therefore, the biological homochirality problem may be reduced to ensuring that a single common RNA precursor (e.g., RAO) can be made homochiral. The emergence of homochirality at RAO then allows for the chiral information to propagate through RNA, then to peptides, and ultimately through enantioselective catalysis to metabolites. This directionality of the chiral information flow parallels that of the central dogma of molecular biology—the unidirectional transfer of genetic information from nucleic acids to proteins [F. H. Crick, in Symposia of the Society for Experimental Biology, Number XII: The Biological Replication of Macromolecules, edited by F. K. Sanders (Cambridge University Press, Cambridge, 1958), pp. 138-163; and F. Crick, Nature 227, 561 (1970)]. [ABSTRACT FROM AUTHOR]

The significance of pay bargaining among nurses in light of labor shortages in the United Kingdom National Health Service is discussed.

The potential of environmental bacteria to biotransform antibacterial agent Norfloxacin is investigated. Results show that biotransformation reduces the antibacterial activity of norfloxacin and therefore my serve as a mechanism facilitating fluoroquinolone resistance.