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Review

21 February 2024

One-pot Multi-enzyme Cascade Synthesis of Bifunctional Compounds from Vegetable Oils

Green and efficient biocatalytic technology has become a complementary or alternative means of organic synthesis. Chemicals with two functional groups, such as α,ω-dicarboxylic acids, ω-amino fatty acids and ω-hydroxy fatty acids, are widely used in the synthesis of polymers such as polyesters and polyamides. In recent years, the production of biodegradable materials using renewable and abundant vegetable oils as green raw materials has attracted increasing attention, receiving an additional impetus from synthetic biology. This paper presents the recent research progress in the production of bifunctional chemicals with medium chain lengths of C8–C12 using multi-enzyme cascades. Recent studies have developed multilevel optimization strategies to improve the efficiency, economics, and sustainability of multi-enzyme cascades. Cofactor regeneration strategies were developed to avoid large additions of expensive coenzymes. Protein engineering strategies were applied to improve enzyme stability and catalytic performance. In addition, blocking the β-oxidation pathway, improving the efficiency of substrate transport across membranes and increasing cellular robustness are effective optimization strategies for whole-cell catalytic systems. In addition, we discuss the development prospects of producing high value-added fine chemicals from vegetable oils using one-pot multi-enzyme reaction systems.

Keywords: Bifunctional compounds; Vegetable oils; One-pot multi-enzyme cascade reaction; Medium-chain fatty acids

Meeting Report

20 February 2024

The Cellular and Metabolic Bases of Organ Fibrosis: UNIA Workshop 2023 in Baeza, Spain

Fibrosis is defined by scarring and tissue hardening caused by excess deposition of extracellular matrix components, mainly collagens. A fibrotic response can occur in any tissue of the body and is the final outcome of an unbalanced reaction to inflammation and wound healing induced by a variety of insults, including persistent infections, autoimmune reactions, allergic responses, chemical exposure, radiation, and tissue injury. The accumulation of extracellular matrix proteins replaces the living tissue and disrupts the architecture leading to organ malfunction. Fibrosis remains a major clinical and therapeutic challenge and has been estimated to account for 45% of deaths in the developed world. While major advances regarding mechanistic knowledge on the underlying cell biology alterations in fibrosis have helped to characterize the main phases and mediators involved, this knowledge has not yielded significant progress in treatment. Only recently, the metabolic features associated to fibrosis have begun to emerge. This information, likely representing only the tip of the iceberg, suggests that metabolic derangement is a key culprit in the pathophysiology of fibrogenesis. The Workshop on The Cellular and Metabolic Bases of Organ Fibrosis, International University of Andalusia, Baeza, Spain, October 8–11, 2023 aimed to discuss the current knowledge and novel perspectives on the mechanisms contributing to the development of fibrosis in different organs and tissues, with particular focus on new methodological developments in metabolomics and therapeutic strategies.

Keywords: Fibrosis; Fibroblast; Inflammation; Metabolism; Tissue repair

Article

20 February 2024

Wind Influence on the Electrical Energy Production of Solar Plants

Solar energy, as a clean source of energy, plays a relevant role in this much desired (r)evolution. When talking about photovoltaics, despite the multiple studies on parameters that affect the panels operation, concrete knowledge on this matter is still in an incipient stage and precise data remains dispersed, given the mutability of outer factors beyond technology-related properties, hence the difficulties associated with exploration. Wind is one of them. Wind loads can affect the temperature of photovoltaics, whose efficiency is reduced when higher temperatures are reached. The viability of wind as natural cooling mechanism for solar plants and its influence on their electrical energy production is studied in this research work. Some appropriate results were achieved: depending on the module temperature prediction model used and on the photovoltaic technology in question, solar panels are foreseen to be up to approximately 3% more productive for average wind speeds and up to almost 7% more productive for higher speeds. Taking into consideration that wind speed values were collected in the close vicinity of the modules, these results can be proven to be even higher. That being said, this article contributes with accurate insights about wind influence on electrical energy production of solar plants.

Keywords: Optoelectronics; Photovoltaics; Renewable energies; Solar energy; Wind influence

Article

18 February 2024

The Sustainable Development Concept in the Polish Legal Space from a Legal-Dogmatic Perspective

The sustainable development concept is of crucial importance for the socioeconomic development processes, not only at the international community level, but also—or, perhaps, particularly—at the national or even local levels. The aim of the article is to demonstrate, from a legal-dogmatic perspective, the place, role and significance of the sustainable development concept in the Polish legal space. This perspective applies to both the state policy intended to formulate a strategy which provides a basis for law-making processes and to find normative solutions making it possible to reconcile legally protected values which sometimes compete with one another, with account taken of the needs of future generations. The sustainable development concept has been very broadly followed in Poland not only in the legal doctrine, but also in the doctrine of economic and social sciences. This term has turned out to be such an effective political catchword that it has been commonly abused and, therefore, it has lost a good deal of its social importance; this makes it substantially more difficult to apply a normative approach to the issues related to the implementation of the concept in legislative practice. In the Polish legal space, the sustainable development concept has become the leading theme of many documents and legal acts, particularly those concerned with environmental protection, but also, although to a much more modest extent, those addressing the issues of socioeconomic development.

Keywords: Sustainable development; Brundtland Report; Notions and definitions; Polish Constitution; Legal character of principle of sustainable development; Polish policy and law on sustainable development

Article

31 January 2024

Design of Intelligent and Sustainable Manufacturing Production Line for Automobile Wheel Hub

The wheel hub is an important part of the automobile, and machining affects its service life and driving safety. With the increasing demand for wheel productivity and machining accuracy in the automotive transport sector, automotive wheel production lines are gradually replacing human production. However, the technical difficulties of conventional automotive wheel production lines include insufficient intelligence, low machining precision, and large use of cutting fluid. This paper aims to address these research constraints. The intelligent, sustainable manufacturing production line for automobile wheel hub is designed. First, the machining of automotive wheel hubs is analyzed, and the overall layout of the production line is designed. Next, the process equipment system including the fixture and the minimum quantity lubrication (MQL) system are designed. The fixture achieves self-positioning and clamping functions through a linkage mechanism and a crank–slider mechanism, respectively, and the reliability of the mechanism is analyzed. Finally, the trajectory planning of the robot with dual clamping stations is performed by RobotStodio. Results show the machining parameters for a machining a wheel hub with a diameter of 580 mm are rotational speed of 2500 rpm, cutting depth of 4 mm, feed rate of 0.5 mm/r, and minimum clamping force of 10881.75 N. The average time to move the wheel hub between the roller table and each machine tool is 27 s, a reduction of 6 s compared with the manual handling time. The MQL system effectively reduces the use of cutting fluid. This production line can provide a basis and reference for actual production by reasonably planning the wheel hub production line.

Keywords: Automobile wheel hub; Production line; Machining; Fixture; Sustainable manufacturing

Article

29 January 2024

A Novel High Step-up DC-DC Converter Using State Space Modelling Technique for Battery Storage Applications

This paper focuses a novel non-isolated coupled inductor based DC-DC converter with excessive VG (voltage gain) is analyzed with a state-space modeling technique. It builds up of using three diodes, three capacitors, an inductor and CI (coupled inductor). The main switch S is turn on due to body diode and voltage stress is reduced at the switch S by using diode D1 and Capacitor C1. This paper focuses on design modelling, mathematical calculations and operation principle of DC-DC converter is discussed with state-space modelling technique. The performance has been presented for two different voltages for EV applications, i.e., 12 V, 48 V as input voltages with a high step-up outputs of 66 V and 831.7 V respectively. The converter stability is studied and determined the bode plot along with simulation performance results which are carried out using MATLAB R2022B.

Keywords: DC-DC Converter; Energy Storage System; High Step-Up; State-Space Modelling

Article

29 January 2024

The “Global Change Data Base” GCDB Facilitates a Transition to Clean Energy and Sustainability

This article presents the opportunities for constructing a global data base picturing underlying trends that drive global climate change. Energy-related CO2 emissions currently represent the key impact on climate change and thus become here the object of deep, long-term and historiographic analysis. In order to embrace all involved domains of technology, energy economy, fuel shares, economic efficacity, economic structure and population, a “Global Change Data Base” (GCDB) is suggested, based on earlier worldwide accepted data repositories. Such a GCDB works through regressions and statistical analysis of time series of data (on extensive magnitudes such as energy demand, population or Gross Domestic Product, GDP) as well as generation of derived data such as quotients of the former, yielding intensive magnitudes that describe systems and their structural properties. Moreover, the GCDB sets out to compute the first and second time derivatives of said magnitudes (and their percentual shares) which indicate new long-term developments already at very early phases. The invitation to participate in this foresight endeavour is extended to all readers. First preliminary GCDB results quantitatively portray the evolutionary structural global dynamics of economic growth, sectoral economic shifts, the shifts within energy carriers in various economic sectors, the ongoing improvements of energy intensity and energy efficiency in many economic sectors, and the structural changes within agricultural production and consumption systems.

Keywords: Forward looking; Future research; Techno-socio-economic evolution; Global development; Global scenarios; National scenarios; Foresight; Forecast; Technology assessment; Energy; Economy; Agriculture; Global Change Data Base (GCDB); Global change; Global studies; Climate change; Energy; Sustainability

Editorial

25 January 2024

Article

23 January 2024

Analysis of a σ54 Transcription Factor L420P Mutation in Context of Increased Organic Nitrogen Tolerance of Photofermentative Hydrogen Production in Cereibacter sphaeroides Strain 2.4.1 Substrain H2

Photofermentative hydrogen production with non-sulfur purple bacteria like Cereibacter sphaeroides (formerly Rhodobacter sphaeroides) is a promising and sustainable process to convert organic waste into the energy carrier hydrogen gas. However, this conversion is inhibited by elevated organic nitrogen concentrations in the substrate, which limits its applicability to nitrogen-poor organic waste. We present genomic and transcriptomic insights into a substrain of Cereibacter sphaeroides strain 2.4.1 that shows unexpected high levels of photofermentative hydrogen evolution when fed with glutamate. Genome sequencing revealed 222 single nucleotide variances (SNVs) between the reference genome of C. sphaeroides strain 2.4.1 and the analyzed substrain H2. These affect 61 protein coding genes. A leucine-proline exchange is present in the σ54 factor (rpoN2 gene), a global hydrogen and nitrogen metabolism regulator. We propose a model how this mutation alters DNA-binding properties that explain the unexpected organic nitrogen tolerance of hydrogen production. Transcriptomic analyses under varying glutamate concentrations support this finding. Thus, we present the first thorough genomic and transcriptomic analysis of a Cereibacter strain that shows promising metabolic characteristics for biotechnological hydrogen gas production from organic waste. These results suggest a potential target for strain optimization. Possibly, our key finding can be transferred to other hydrogen producing microorganisms.

Keywords: Bioenergy; Photobiological hydrogen production; Re-sequencing; Transcriptomic analysis; RNASeq; σ54; RpoN; Sigma factor

Article

16 January 2024

The Interplay between Experimental Data and Uncertainty Analysis in Quantifying CO2 Trapping during Geological Carbon Storage

Numerical simulation is a widely used tool for studying CO2 storage in porous media. It enables the representation of trapping mechanisms and CO2 retention capacity. The complexity of the involved physicochemical phenomena necessitates multiphase flow, accurate fluid and rock property representation, and their interactions. These include CO2 solubility, diffusion, relative permeabilities, capillary pressure hysteresis, and mineralization, all crucial in CO2 trapping during carbon storage simulations. Experimental data is essential to ensure accurate quantification. However, due to the extensive data required, modeling under uncertainty is often needed to assess parameter impacts on CO2 trapping and its interaction with geological properties like porosity and permeability. This work proposes a framework combining laboratory data and stochastic parameter distribution to map uncertainty in CO2 retention over time. Published data representing solubility, residual trapping, and mineral trapping are used to calibrate prediction models. Geological property variations, like porosity and permeability, are coupled to quantify uncertainty. Results from a saline sandstone aquifer model demonstrate significant variation in CO2 trapping, ranging from 17% (P10 estimate) to 56% (P90), emphasizing the importance of considering uncertainty in CO2 storage projects. Quadratic response surfaces and Monte Carlo simulations accurately capture this uncertainty, resulting in calibrated models with an R-squared coefficient above 80%. In summary, this work provides a practical and comprehensive framework for studying CO2 retention in porous media, addressing uncertainty through stochastic parameter distributions, and highlighting its importance in CO2 storage projects. 

Keywords: CO2 trapping mechanisms; CCS; Uncertainty analysis; Proxy models; Saline aquifer
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