Metabolic control exerted by the 2-oxoglutarate dehydrogenase reaction: a cross-kingdom comparison of the crossroad between energy production and nitrogen assimilation

2009 ◽  
Vol 422 (3) ◽  
pp. 405-421 ◽  
Author(s):  
Victoria I. Bunik ◽  
Alisdair R. Fernie
Keyword(s):  
Metabolic Control ◽  
Nitrogen Assimilation ◽  
Biological Systems ◽  
Wound Response ◽  
Metabolic Adaptation ◽  
Oxidative Decarboxylation ◽  
Dehydrogenase Reaction ◽  
Wide Range ◽  
The Impact

Mechanism-based inhibitors and both forward and reverse genetics have proved to be essential tools in revealing roles for specific enzymatic processes in cellular function. Here, we review experimental studies aimed at assessing the impact of OG (2-oxoglutarate) oxidative decarboxylation on basic cellular activities in a number of biological systems. After summarizing the catalytic and regulatory properties of the OGDHC (OG dehydrogenase complex), we describe the evidence that has been accrued on its cellular role. We demonstrate an essential role of this enzyme in metabolic control in a wide range of organisms. Targeting this enzyme in different cells and tissues, mainly by its specific inhibitors, effects changes in a number of basic functions, such as mitochondrial potential, tissue respiration, ROS (reactive oxygen species) production, nitrogen metabolism, glutamate signalling and survival, supporting the notion that the evolutionary conserved reaction of OG degradation is required for metabolic adaptation. In particular, regulation of OGDHC under stress conditions may be essential to overcome glutamate excitotoxicity in neurons or affect the wound response in plants. Thus, apart from its role in producing energy, the flux through OGDHC significantly affects nitrogen assimilation and amino acid metabolism, whereas the side reactions of OGDHC, such as ROS production and the carboligase reaction, have biological functions in signalling and glyoxylate utilization. Our current view on the role of OGDHC reaction in various processes within complex biological systems allows us a far greater fundamental understanding of metabolic regulation and also opens up new opportunities for us to address both biotechnological and medical challenges.

History and Morality

2020 ◽  
Author(s):  
Donald Bloxham
Keyword(s):  
Foreign Country ◽  
Moral Thought ◽  
Majority Opinion ◽  
The Past ◽  
Wide Range ◽  
Moral Judgements ◽  
Value Judgements ◽  
The Impact

Against majority opinion within his profession, Donald Bloxham argues that it is legitimate, often unavoidable, and frequently important for historians to make value judgements about the past. History and Morality draws on a wide range of historical examples, and its author’s insights as a practising historian. Examining concepts like impartiality, neutrality, contextualization, and the use and abuse of the idea of the past as a foreign country, Bloxham’s book investigates how the discipline has got to the point where what is preached can be so inconsistent with what is practised. It illuminates how far tacit moral judgements infuse works of history, and how strange those histories would look if the judgements were removed. Bloxham argues that rather than trying to eradicate all judgemental elements from their work historians need to think more consistently about how, and with what justification, they make the judgements that they do. The importance of all this lies not just in the responsibilities that historians bear towards the past—responsibilities to take historical actors on those actors’ own terms and to portray the impact of those actors’ deeds—but also in the role of history as a source of identity, pride, and shame in the present. The account of moral thought in History and Morality has ramifications far beyond the activities of vocational historians.

scholarly journals Scale dependence of cirrus heterogeneity effects. Part II: MODIS NIR and SWIR channels

2018 ◽  
Vol 18 (16) ◽  
pp. 12105-12121 ◽  
Author(s):  
Thomas Fauchez ◽  
Steven Platnick ◽  
Tamás Várnai ◽  
Kerry Meyer ◽  
Céline Cornet ◽  
...  
Keyword(s):  
Radiative Transfer ◽  
Spatial Resolution ◽  
Thermal Infrared ◽  
Radiative Effects ◽  
Ice Clouds ◽  
Plane Parallel ◽  
Wide Range ◽  
The Impact ◽  
Side Illumination

Abstract. In a context of global climate change, the understanding of the radiative role of clouds is crucial. On average, ice clouds such as cirrus have a significant positive radiative effect, but under some conditions the effect may be negative. However, many uncertainties remain regarding the role of ice clouds on Earth's radiative budget and in a changing climate. Global satellite observations are particularly well suited to monitoring clouds, retrieving their characteristics and inferring their radiative impact. To retrieve ice cloud properties (optical thickness and ice crystal effective size), current operational algorithms assume that each pixel of the observed scene is plane-parallel and homogeneous, and that there is no radiative connection between neighboring pixels. Yet these retrieval assumptions are far from accurate, as real radiative transfer is 3-D. This leads to the plane-parallel and homogeneous bias (PPHB) plus the independent pixel approximation bias (IPAB), which impacts both the estimation of top-of-the-atmosphere (TOA) radiation and the retrievals. An important factor that determines the impact of these assumptions is the sensor spatial resolution. High-spatial-resolution pixels can better represent cloud variability (low PPHB), but the radiative path through the cloud can involve many pixels (high IPAB). In contrast, low-spatial-resolution pixels poorly represent the cloud variability (high PPHB), but the radiation is better contained within the pixel field of view (low IPAB). In addition, the solar and viewing geometry (as well as cloud optical properties) can modulate the magnitude of the PPHB and IPAB. In this, Part II of our study, we simulate TOA 0.86 and 2.13 µm solar reflectances over a cirrus uncinus scene produced by the 3DCLOUD model. Then, 3-D radiative transfer simulations are performed with the 3DMCPOL code at spatial resolutions ranging from 50 m to 10 km, for 12 viewing geometries and nine solar geometries. It is found that, for simulated nadir observations taken at resolution higher than 2.5 km, horizontal radiation transport (HRT) dominates biases between 3-D and 1-D reflectance calculations, but these biases are mitigated by the side illumination and shadowing effects for off-zenith solar geometries. At resolutions coarser than 2.5 km, PPHB dominates. For off-nadir observations at resolutions higher than 2.5 km, the effect that we call THEAB (tilted and homogeneous extinction approximation bias) due to the oblique line of sight passing through many cloud columns contributes to a large increase of the reflectances, but 3-D radiative effects such as shadowing and side illumination for oblique Sun are also important. At resolutions coarser than 2.5 km, the PPHB is again the dominant effect. The magnitude and resolution dependence of PPHB and IPAB is very different for visible, near-infrared and shortwave infrared channels compared with the thermal infrared channels discussed in Part I of this study. The contrast of 3-D radiative effects between solar and thermal infrared channels may be a significant issue for retrieval techniques that simultaneously use radiative measurements across a wide range of solar reflectance and infrared wavelengths.

Business Ethics is Socio-Political, or Not at All

2015 ◽  
pp. 251-281
Author(s):  
Ana-Maria Pascal
Keyword(s):  
Business Ethics ◽  
Theoretical Background ◽  
Kantian Ethics ◽  
Political Responsibility ◽  
Wide Range ◽  
Mining Project ◽  
Public Ethics ◽  
High Degree ◽  
The Impact

This chapter explores the moral aspects of commercial deals that allegedly democratic governments enter into with foreign investors. These are discussed against a twofold theoretical background – where the philosophical ideal of public ethics based on truth and transparency meets business ethics theories. The Kantian ethics of duty proves to be the key link between these, as particularly relevant for cases where the impact on a wide range of stakeholders is considerable. The main case under consideration is the controversial USD $2 billion Romanian mining project at Rosia Montana, which highlights the need for accountability mentioned above and lends itself well to a multi-fold business ethics analysis. The role of the civil society in effectively stopping the project is a good illustration of the stakeholder theory. The chapter concludes with the thesis that a high degree of socio-political responsibility may be best achieved when trying to combine principle-based and utilitarian thinking.

scholarly journals Second hits exacerbate alcohol-related organ damage: an update

2020 ◽  
Vol 56 (1) ◽  
pp. 8-16
Author(s):  
Natalia A Osna ◽  
Murali Ganesan ◽  
Devanshi Seth ◽  
Todd A Wyatt ◽  
Srivatsan Kidambi ◽  
...  
Keyword(s):  
Liver Injury ◽  
Alcohol Exposure ◽  
Organ Damage ◽  
Lifestyle Factor ◽  
Matrix Stiffness ◽  
Reactive Aldehydes ◽  
Wide Range ◽  
Excessive Alcohol ◽  
The Impact

Abstract Chronic and excessive alcohol abuse cause direct and indirect detrimental effects on a wide range of body organs and systems and accounts for ~4% of deaths worldwide. Many factors influence the harmful effects of alcohol. This concise review presents newer insights into the role of select second hits in influencing the progression of alcohol-induced organ damage by synergistically acting to generate a more dramatic downstream biological defect. This review specifically addresses on how a lifestyle factor of high fat intake exacerbates alcoholic liver injury and its progression. This review also provides the mechanistic insights into how increasing matrix stiffness during liver injury promotes alcohol-induced fibrogenesis. It also discusses how hepatotropic viral (HCV, HBV) infections as well as HIV (which is traditionally not known to be hepatotropic), are potentiated by alcohol exposure to promote hepatotoxicity and fibrosis progression. Finally, this review highlights the impact of reactive aldehydes generated during alcohol and cigarette smoke coexposure impair innate antimicrobial defense and increased susceptibility to infections. This review was inspired by the symposium held at the 17th Congress of the European Society for Biomedical research on Alcoholism in Lille, France entitled ‘Second hits in alcohol-related organ damage’.

scholarly journals Who stands to benefit? Wellbeing, belonging and challenges to equity in engagement in extra-curricular activities at university

2020 ◽  
pp. 146978742090820 ◽  
Author(s):  
Naomi Winstone ◽  
Kieran Balloo ◽  
Karen Gravett ◽  
Daniel Jacobs ◽  
Harry Keen
Keyword(s):  
Sense Of Belonging ◽  
Individual Characteristics ◽  
Student Identity ◽  
Mediating Role ◽  
Wide Range ◽  
Extra Curricular Activities ◽  
The University ◽  
The Impact ◽  
Perceived Outcomes

Students’ engagement in extra-curricular activities can play a significant role in their development of a student identity, as well as leading to a greater sense of belonging and wellbeing. However, individual characteristics such as sociability may influence the likelihood of students engaging in extra-curricular activities. We collected mixed mode data from two online surveys to explore students’ perceptions of the impact of engagement in extra-curricular activities on their experience at university, as well as the mediating role of engagement in extra-curricular activities in the relationships between extraversion and wellbeing and sense of belonging to the University. Our data demonstrate that extraversion is positively associated with both belonging and wellbeing, and that engagement in extra-curricular activities also mediates these relationships. Our qualitative data uncover further nuances in engagement with extra-curricular activities; while many perceived outcomes are positive, some students express regret at opportunities missed, and find it challenging to balance extra-curricular activities and their studies. Taken together, these findings indicate that not all students stand to benefit equally from engagement in extra-curricular activities. Providing a range of opportunities that are accessible to a wide range of students may promote equity in participation in extra-curricular activities.

Ever-Widening Ripples: The Impact of Specialist Industrial Tribunals on Management Practice

1994 ◽  
Vol 36 (2) ◽  
pp. 285-298 ◽  
Author(s):  
Louise Thornthwaite
Keyword(s):  
Management Practice ◽  
Industrial Relations ◽  
Employment Relations ◽  
Employment Decisions ◽  
Public Role ◽  
South Wales ◽  
Wide Range ◽  
The Government ◽  
The Impact

While conciliation and arbitration tribunals have been at the forefront of Austral ian research on industrial relations institutions, numerous specialist tribunals enforcing individual workers' rights in employment have been virtually hidden from view. This paper examines the role of two such tribunals in New South Wales, the Government and Related Employees' Appeal Tribunal and the Equal Opportu nity Tribunal. It argues that although their most direct and public role is to resolve individuals' grievances, equally significant is the contribution of these agencies to the detailed regulation of employment relations and hence the increasing sophisti cation of labour management in public sector organizations since the late 1970s, and the institutionalization of management prerogatives and conflicts over an increasingly wide range of employment decisions.

scholarly journals Adopting Computer Technology to empower Rural School Learners: The Case for Katsande Rural School Library, Zimbabwe

2019 ◽  
Author(s):  
Hosea Tokwe
Keyword(s):  
Computer Technology ◽  
New Technologies ◽  
School Library ◽  
School Libraries ◽  
Rural School ◽  
Reading Material ◽  
Wide Range ◽  
The Impact ◽  
Technology In Schools

In most countries, the introduction of computer technology in schools has seen the role of school libraries transformed. Adoption of new technologies are now seen to be enhancing school libraries’ ability to perform their mission, vision and role, that is, providing learners access to a wide range of reading material to enable them to acquire knowledge as well as ability to read books online. This paper will address the impact computer technology is having on rural school learners at Katsande Primary School. It will explain how embracing of computer technology has influenced learners concerning achieving quality education. 

scholarly journals From Nursery to Nursing Home: Emerging Concepts in Clostridioides difficile Pathogenesis

2020 ◽  
Vol 88 (7) ◽  
Author(s):  
Alexander B. Smith ◽  
Joshua Soto Ocana ◽  
Joseph P. Zackular
Keyword(s):  
Pharmaceutical Drugs ◽  
Human Gastrointestinal Tract ◽  
Content Type ◽  
The Past ◽  
Clostridioides Difficile ◽  
Wide Range ◽  
Pediatric Populations ◽  
The Impact ◽  
Shed Light

ABSTRACT Clostridioides difficile is a Gram-positive, spore-forming, anaerobic bacterium that infects the human gastrointestinal tract, causing a wide range of disorders that vary in severity from mild diarrhea to toxic megacolon and/or death. Over the past decade, incidence, severity, and costs associated with C. difficile infection (CDI) have increased dramatically in both the pediatric and adult populations. The factors driving this rapidly evolving epidemiology remain largely unknown but are likely due in part to previously unappreciated host, microbiota, and environmental factors. In this review, we will cover the risks and challenges of CDI in adult and pediatric populations and examine asymptomatic colonization in infants. We will also discuss the emerging role of diet, pharmaceutical drugs, and pathogen-microbiota interactions in C. difficile pathogenesis, as well as the impact of host-microbiota interactions in the manifestation of C. difficile-associated disease. Finally, we highlight new areas of research and novel strategies that may shed light on this complex infection and provide insights into the future of microbiota-based therapeutics for CDI.

Assessment in American Higher Education: The Role of Admissions Tests

2019 ◽  
Vol 683 (1) ◽  
pp. 130-148 ◽  
Author(s):  
Rebecca Zwick
Keyword(s):  
Higher Education ◽  
United States ◽  
The United States ◽  
College Performance ◽  
Admissions Tests ◽  
Higher Education System ◽  
Wide Range ◽  
Test Optional ◽  
The Impact

In this article, I review the role of college admissions tests in the United States and consider the fairness issues surrounding their use. The two main tests are the SAT, first administered in 1926, and the ACT, first given in 1959. Scores on these tests have been shown to contribute to the prediction of college performance, but their role in the admissions process varies widely across colleges. Although test scores are consistently listed as one of the most important admissions factors in national surveys of postsecondary institutions, an increasing number of schools have adopted “test-optional” policies. At these institutions, test score requirements are seen as a barrier to campus diversity because of the large performance gaps among ethnic and socioeconomic groups. Fortunately, the decentralized higher education system in the United States can accommodate a wide range of admissions policies. It is essential, however, that the impact of admissions policy changes be studied and that the resource implications of these changes be thoroughly considered.

scholarly journals Role of Killer Immunoglobulin-Like Receptor and Ligand Matching in Donor Selection

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Meral Beksaç ◽  
Klara Dalva
Keyword(s):  
Stem Cell ◽  
T Cell ◽  
Stem Cell Transplantation ◽  
Cell Transplantation ◽  
Nk Cell ◽  
Immune Defense ◽  
Hla Typing ◽  
Wide Range ◽  
The Impact

Despite all efforts to improve HLA typing and immunosuppression, it is still impossible to prevent severe graft versus host disease (GVHD) which can be fatal. GVHD is not always associated with graft versus malignancy and can prevent stem cell transplantation from reaching its goals. Overall T-cell alloreactivity is not the sole mechanism modulating the immune defense. Innate immune system has its own antigens, ligands, and mediators. The bridge between HLA and natural killer (NK) cell-mediated reactions is becoming better understood in the context of stem cell transplantation. Killer immunoglobulin-like receptors (KIRs) constitute a wide range of alleles/antigens segregated independently from the HLA alleles and classified into two major haplotypes which imprints the person's ability to suppress or to amplify T-cell alloreactivity. This paper will summarize the impact of both activating and inhibitory KIRs and their ligands on stem cell transplantation outcome. The ultimate goal is to develop algorithms based on KIR profiles to select donors with maximum antileukemic and minimum antihost effects.

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