Progress towards platform chemical production using Clostridium autoethanogenum

2018 ◽  
Vol 46 (3) ◽  
pp. 523-535 ◽  
Author(s):  
Rupert O.J. Norman ◽  
Thomas Millat ◽  
Klaus Winzer ◽  
Nigel P. Minton ◽  
Charlie Hodgman
Keyword(s):  
Systems Biology ◽  
Greenhouse Gases ◽  
Research Articles ◽  
Future Research ◽  
Chemical Production ◽  
Platform Chemicals ◽  
Platform Chemical ◽  
Clostridium Autoethanogenum

Since 2013, there has been an explosion in the number of research articles published on Clostridium autoethanogenum, an acetogen capable of producing platform chemicals such as ethanol and 2,3-butanediol from greenhouse gases. However, no review focusing solely on C. autoethanogenum has appeared in the literature. This review outlines the research conducted into this organism in three broad categories (Enzymology, Genetics, and Systems Biology) and suggestions for future research are offered.

International Archival Auditing and Assurance Research: Trends, Methodological Issues, and Opportunities

2016 ◽  
Vol 35 (3) ◽  
pp. 1-32 ◽  
Author(s):  
Roger Simnett ◽  
Elizabeth Carson ◽  
Ann Vanstraelen
Keyword(s):  
Audit Quality ◽  
Research Trends ◽  
Data Sources ◽  
Quality Data ◽  
Research Articles ◽  
Future Research ◽  
Evidence Based ◽  
Methodological Issues ◽  
Comprehensive Review ◽  
Support Evidence

SUMMARY We present a comprehensive review of the 130 international archival auditing and assurance research articles that were published in eight leading accounting and auditing journals for 1995–2014. In order to support evidence-based international standard setting and regulation, and to identify what has been learned to date, we map this research to the International Auditing and Assurance Standards Board's (IAASB) Framework for Audit Quality. For the areas that have been well researched, we provide a summary of the findings and outline how they can inform standard setters and regulators. We also observe a significant evolution in international archival research over the 20 years of our study, as evidenced by the measures of audit quality, data sources used, and approaches used to address endogeneity concerns. Finally, we identify some challenges in undertaking international archival auditing and assurance research and identify opportunities for future research. Our review is of interest to researchers, practitioners, and standard setters/regulators involved in international auditing and assurance activities.

scholarly journals Drivers of changes in stratospheric and tropospheric ozone between year 2000 and 2100

2016 ◽  
Vol 16 (5) ◽  
pp. 2727-2746 ◽  
Author(s):  
Antara Banerjee ◽  
Amanda C. Maycock ◽  
Alexander T. Archibald ◽  
N. Luke Abraham ◽  
Paul Telford ◽  
...  
Keyword(s):  
Climate Change ◽  
Greenhouse Gases ◽  
Tropospheric Ozone ◽  
Climate Forcing ◽  
Atmospheric Response ◽  
Chemical Production ◽  
The United Kingdom ◽  
Ozone Precursor ◽  
Ozone Depleting Substances ◽  
Year 2000

Abstract. A stratosphere-resolving configuration of the Met Office's Unified Model (UM) with the United Kingdom Chemistry and Aerosols (UKCA) scheme is used to investigate the atmospheric response to changes in (a) greenhouse gases and climate, (b) ozone-depleting substances (ODSs) and (c) non-methane ozone precursor emissions. A suite of time-slice experiments show the separate, as well as pairwise, impacts of these perturbations between the years 2000 and 2100. Sensitivity to uncertainties in future greenhouse gases and aerosols is explored through the use of the Representative Concentration Pathway (RCP) 4.5 and 8.5 scenarios. The results highlight an important role for the stratosphere in determining the annual mean tropospheric ozone response, primarily through stratosphere–troposphere exchange (STE) of ozone. Under both climate change and reductions in ODSs, increases in STE offset decreases in net chemical production and act to increase the tropospheric ozone burden. This opposes the effects of projected decreases in ozone precursors through measures to improve air quality, which act to reduce the ozone burden. The global tropospheric lifetime of ozone (τO3) does not change significantly under climate change at RCP4.5, but it decreases at RCP8.5. This opposes the increases in τO3 simulated under reductions in ODSs and ozone precursor emissions. The additivity of the changes in ozone is examined by comparing the sum of the responses in the single-forcing experiments to those from equivalent combined-forcing experiments. Whilst the ozone responses to most forcing combinations are found to be approximately additive, non-additive changes are found in both the stratosphere and troposphere when a large climate forcing (RCP8.5) is combined with the effects of ODSs.

Unveiling contemporary dimensions in the internationalisation of family firms through bibliometric analysis and thematic analysis

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Sonal Thukral ◽  
Apoorva Jain
Keyword(s):  
Bibliometric Analysis ◽  
Thematic Analysis ◽  
Family Firms ◽  
Research Area ◽  
Research Articles ◽  
Future Research ◽  
Content Type ◽  
Holistic Understanding ◽  
The Family ◽  
Research Stream

Purpose For sustaining a competitive advantage in the integrated world economy, it has become imperative for family firms to internationalise their operations in overseas markets. However, despite the growing set of literature, results are still inconclusive with respect to family firms’ internationalisation. Thus, this study aims to address this gap by systematically reviewing 142 articles (1991–2019) to help researchers in identifying and unfolding the unexplored themes in the underlying area. Design/methodology/approach For systematically reviewing articles, the study uses a three-step methodology following PRISMA guidelines, bibliometric analysis and thematic analysis. Descriptive statistics of 142 research articles are obtained through bibliometric analysis while thematic analysis is carried out to create themes or clusters of various factors relating to family firms’ internationalisation. Findings The current review uncovers the evolving trends in the research streams, most productive authors, top journals and articles, co-citation analysis, as well as the major themes surrounding the family firms’ internationalisation literature. Results from bibliometric analysis indicate that family firms’ internationalisation is an upcoming research area. Also, the review indicates an opportunity for scholars from developing nations to make significant contributions in the underlying research stream. Research limitations/implications Results from bibliometric and thematic analysis will help academicians and researchers in accumulating a holistic understanding relating to family firms’ internationalisation and understanding the upcoming trends in family firms’ research, thereby guiding the future research scope. Also, it will assist the family firms’ leaders and managers in understanding the important dynamics in overseas markets and various factors to be considered while planning their internationalisation. Originality/value Undertaking a systematic literature review presents readers with a state-of-the-art understanding of the underlying research topic. To the best of the knowledge, to date, the study is the first to conduct the review of literature through bibliometric analysis with the help of R Studio software in the field of family firms’ internationalisation. Also, the study is the first to review more than 100 research articles in the underlying area. Finally, the study proposes a comprehensive framework integrating the major themes and facets relating to family firms’ internationalisation.

scholarly journals Life: Computational Genomics Applications in Life Sciences

Life ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1211
Author(s):  
Yuriy L. Orlov ◽  
Anastasia A. Anashkina
Keyword(s):  
Systems Biology ◽  
Life Sciences ◽  
Computational Genomics ◽  
Research Articles ◽  
Special Issue

This Special Issue, “Life: Computational Genomics”, presents research articles on systems biology applications, computational genomics, and bioinformatics methods in life sciences [...]

scholarly journals Reverse Logistics for Solid Waste from the Construction Industry

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Manuel Vargas ◽  
Miguel Alfaro ◽  
Natalia Karstegl ◽  
Guillermo Fuertes ◽  
María D. Gracia ◽  
...  
Keyword(s):  
Solid Waste ◽  
Construction Industry ◽  
Reverse Logistics ◽  
Scientific Literature ◽  
Current Knowledge ◽  
Research Articles ◽  
Future Research ◽  
General Management ◽  
Literature Reviews ◽  
The Relationship

This article reviews studies on the application of reverse logistics in solid waste from the construction industry. The main objective is to provide a summary of current knowledge and specific areas for future research. In addition, construction, as an economic sector, is in a continuous search for new tools to improve its processes, so this research provides the current situation of the relationship between reverse logistics and solid waste in the industry. The review methodology was content analysis of scientific literature published between 1997 and 2020, and total of 66 articles were used. 73% correspond to research articles, around 13% are case studies, and 12% are literature reviews. Only one of the articles is a survey. In addition, 52% of the works reviewed correspond to solid waste studies and 49% are related to the construction industry; only one publication does not classify in any. The most used keywords for the identification of published works were reverse logistics and supply chain; both terms are frequently related to the process and general management of solid waste and construction. The least used term was the literature review that shows the low number of articles that provide a summary of the proposed topic. Finally, three materials were chosen for the study because they are the most used in construction: metals, bricks, and concrete. 15% of the articles study all three, 18% study only metals, and 63% study other materials or are related to construction and solid waste in general.

Pretreatment of Lignocellulosic Biomass Feedstocks for Biofuel Production

2018 ◽  
pp. 33-60 ◽  
Author(s):  
Desikan Ramesh ◽  
Iniya Kumar Muniraj ◽  
Kiruthika Thangavelu ◽  
Subburamu Karthikeyan
Keyword(s):  
Lignocellulosic Biomass ◽  
Biofuel Production ◽  
Renewable Fuels ◽  
Chemical Production ◽  
Biomass Feedstocks ◽  
Platform Chemical ◽  
Global Concern ◽  
Liquid Biofuel ◽  
Lignocellulosic Pretreatment

The shifting of dependence from conventional fuels to renewable fuels and its increased production to combat the energy, environmental, and geopolitical crises is a global concern. One of the viable and promising alternatives is liquid biofuel production using lignocellulosic biomass. Lignocellulosic biomass being the most abundant encompass cellulose, hemicellulose, and lignin.The intricate complex of hemicellulose and lignin around cellulose is the bottleneck in commercializing the biofuel process. To make the cellulose and hemicellulose more accessible for hydrolysis and valorise the underutilized lignin for platform chemical production, pretreatment becomes imperative. Various pretreatment methods such as physical, mechanical, chemical, biological, and enzymatic and their combinations are employed for the production of bioethanol. It should be stressed that each pretreatment is unique in its condition and in most cases are biomass specific. With the above view, this chapter aims at bringing out the understanding of lignocellulosic pretreatment with updated information in the field.

scholarly journals Soils and climate change: potential impacts on carbon stocks and greenhouse gas emissions, and future research for Australian agriculture

2012 ◽  
Vol 63 (3) ◽  
pp. 269 ◽  
Author(s):  
J. A. Baldock ◽  
I. Wheeler ◽  
N. McKenzie ◽  
A. McBrateny
Keyword(s):  
Climate Change ◽  
Organic Carbon ◽  
Greenhouse Gases ◽  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Future Research ◽  
Biological Processes ◽  
Gas Emissions ◽  
Carbon And Nitrogen ◽  
Biological Cycling

Organic carbon and nitrogen found in soils are subject to a range of biological processes capable of generating or consuming greenhouse gases (CO2, N2O and CH4). In response to the strong impact that agricultural management can have on the amount of organic carbon and nitrogen stored in soil and their rates of biological cycling, soils have the potential to reduce or enhance concentrations of greenhouse gases in the atmosphere. Concern also exists over the potential positive feedback that a changing climate may have on rates of greenhouse gas emission from soil. Climate projections for most of the agricultural regions of Australia suggest a warmer and drier future with greater extremes relative to current climate. Since emissions of greenhouse gases from soil derive from biological processes that are sensitive to soil temperature and water content, climate change may impact significantly on future emissions. In this paper, the potential effects of climate change and options for adaptation and mitigations will be considered, followed by an assessment of future research requirements. The paper concludes by suggesting that the diversity of climate, soil types, and agricultural practices in place across Australia will make it difficult to define generic scenarios for greenhouse gas emissions. Development of a robust modelling capability will be required to construct regional and national emission assessments and to define the potential outcomes of on-farm management decisions and policy decisions. This model development will require comprehensive field datasets to calibrate the models and validate model outputs. Additionally, improved spatial layers of model input variables collected on a regular basis will be required to optimise accounting at regional to national scales.

scholarly journals Food cold chain management

2018 ◽  
Vol 29 (3) ◽  
pp. 792-821 ◽  
Author(s):  
Shashi Shashi ◽  
Roberto Cerchione ◽  
Rajwinder Singh ◽  
Piera Centobelli ◽  
Amir Shabani
Keyword(s):  
The Body ◽  
Cold Chain ◽  
Research Articles ◽  
Future Research ◽  
Research Gaps ◽  
Chain Management ◽  
Content Type ◽  
Effective Strategies ◽  
Research Questions ◽  
Literature Highlight

Purpose Since last few years, cold chain management (CCM) has gained growing interest among practitioners, policymakers, researchers and academicians. The purpose of this paper is to provide a review focused on food cold chain management (FCCM) over the last 16 years to identify state of the art in the literature, highlight research gaps and define appropriate research questions (RQs) for future research. Design/methodology/approach The paper analyzes the content of 89 research articles published on the topic of food cold chain (FCC) from 2001 to 2016 within different journals. The Scopus and Web of Science databases were taken into consideration to shortlist research articles. Henceforth, the authors scrutinized the FCC industry to offer some effective strategies to tackle the chain complexities. The authors also draw interwoven between FCC infrastructure, integration, stakeholders’ interest, value addition, partners’ performance and overall food cold chain performance (FCCP) into a conceptual framework. Findings This paper identifies four research gaps in the literature of FCC concerning the most popular approaches used for the FCCP measurement, the performance measurement metrics, the factors which negatively affect the FCCP and the main sustainability issues in FCC. Originality/value This study identifies RQs which represent possible areas of investigation to improve the body of the FCCP evaluation and management. Furthermore, the FCC practitioners, food authorities and researchers might find this review useful, as it draws a clear picture of research in the respective domain.

scholarly journals Embryo–Maternal Interactions Underlying Reproduction in Mammals

2020 ◽  
Vol 21 (14) ◽  
pp. 4872
Author(s):  
Stefan Bauersachs ◽  
Carmen Almiñana
Keyword(s):  
Current Knowledge ◽  
Mammalian Species ◽  
Stress Factors ◽  
Research Articles ◽  
Future Research ◽  
Original Research ◽  
Special Issue ◽  
New Findings ◽  
As Stress ◽  
The Impact

This Special Issue, “Embryo-Maternal Interactions Underlying Reproduction in Mammals”, gathers a collection of 23 articles, 16 original research articles and 7 up-to-date reviews, providing new findings or summarizing current knowledge on embryo–maternal interactions in seven different mammalian species including humans. Considering the different players involved in these embryo-maternal interactions, articles are mainly focused on one of these different players: the oviduct, the uterus, the embryo or the emergent extracellular vesicles. Additionally, a few articles bring up the impact of reproductive, but also non-reproductive, diseases, as well as stress factors, on the establishment of pregnancy. We hope the readers enjoy this collection of articles and that the knowledge assembled here will support and inspire current and future research investigations. We would like to thank all authors for their contributions to this Special Issue.

scholarly journals Reconstruction of an Acetogenic 2,3-Butanediol Pathway Involving a Novel NADPH-Dependent Primary-Secondary Alcohol Dehydrogenase

2014 ◽  
Vol 80 (11) ◽  
pp. 3394-3403 ◽  
Author(s):  
Michael Köpke ◽  
Monica L. Gerth ◽  
Danielle J. Maddock ◽  
Alexander P. Mueller ◽  
FungMin Liew ◽  
...  
Keyword(s):  
Alcohol Dehydrogenase ◽  
Secondary Alcohol ◽  
Acetolactate Synthase ◽  
Chemical Production ◽  
Content Type ◽  
E Coli ◽  
Gas Fermentation ◽  
Secondary Alcohol Dehydrogenase ◽  
Clostridium Autoethanogenum ◽  
Butanediol Dehydrogenase

ABSTRACTAcetogenic bacteria use CO and/or CO2plus H2as their sole carbon and energy sources. Fermentation processes with these organisms hold promise for producing chemicals and biofuels from abundant waste gas feedstocks while simultaneously reducing industrial greenhouse gas emissions. The acetogenClostridium autoethanogenumis known to synthesize the pyruvate-derived metabolites lactate and 2,3-butanediol during gas fermentation. Industrially, 2,3-butanediol is valuable for chemical production. Here we identify and characterize theC. autoethanogenumenzymes for lactate and 2,3-butanediol biosynthesis. The putativeC. autoethanogenumlactate dehydrogenase was active when expressed inEscherichia coli. The 2,3-butanediol pathway was reconstituted inE. coliby cloning and expressing the candidate genes for acetolactate synthase, acetolactate decarboxylase, and 2,3-butanediol dehydrogenase. Under anaerobic conditions, the resultingE. colistrain produced 1.1 ± 0.2 mM 2R,3R-butanediol (23 μM h−1optical density unit−1), which is comparable to the level produced byC. autoethanogenumduring growth on CO-containing waste gases. In addition to the 2,3-butanediol dehydrogenase, we identified a strictly NADPH-dependent primary-secondary alcohol dehydrogenase (CaADH) that could reduce acetoin to 2,3-butanediol. Detailed kinetic analysis revealed that CaADH accepts a range of 2-, 3-, and 4-carbon substrates, including the nonphysiological ketones acetone and butanone. The high activity of CaADH toward acetone led us to predict, and confirm experimentally, thatC. autoethanogenumcan act as a whole-cell biocatalyst for converting exogenous acetone to isopropanol. Together, our results functionally validate the 2,3-butanediol pathway fromC. autoethanogenum, identify CaADH as a target for further engineering, and demonstrate the potential ofC. autoethanogenumas a platform for sustainable chemical production.

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