Edaphic, structural and physiological contrasts across Amazon Basin forest-savanna ecotones suggest a role for potassium as a key modulator of tropical woody vegetation structure and function

Abstract. Sampling along a precipitation gradient in tropical America extending from ca. 0.8 to 2.0 m a−1, savanna soils had consistently lower exchangeable cation concentrations and higher C/N ratios than nearby forest plots. These soil differences were also reflected in canopy averaged leaf traits with savanna trees typically having higher leaf mass per unit area but lower mass-based nitrogen (Nm) and potassium (Km). Both Nm and Km also increased with declining mean annual precipitation (PA), but most area-based leaf traits such as leaf photosynthetic capacity showed no systematic variation with PA or vegetation type. Despite this invariance, when taken in conjunction with other measures such mean canopy height, area-based soil exchangeable potassium content, [K]sa, proved to be an excellent predictor of several photosynthetic properties (including 13C isotope discrimination). Moreover, when considered in a multivariate context with PA and soil plant available water storage capacity (θP) as covariates, [K]sa also proved to be an excellent predictor of stand-level canopy area, providing drastically improved fits as compared to models considering just PA and/or θP. Neither calcium, magnesium nor soil pH could substitute for potassium when tested as alternative model predictors (ΔAIC > 10). Nor for any model could simple soil texture metrics such as sand or clay content substitute for either [K]sa or θP. Taken in conjunction with recent work in Africa and the forests of the Amazon Basin this suggests – in combination with some newly conceptualised interacting effects of PA and θP also presented here – a critical role for potassium as a modulator of tropical vegetation structure and function.

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Edaphic, structural and physiological contrasts across Amazon Basin forest–savanna ecotones suggest a role for potassium as a key modulator of tropical woody vegetation structure and function

Biogeosciences ◽

10.5194/bg-12-6529-2015 ◽

2015 ◽

Vol 12 (22) ◽

pp. 6529-6571 ◽

Cited By ~ 35

Author(s):

J. Lloyd ◽

T. F. Domingues ◽

F. Schrodt ◽

F. Y. Ishida ◽

T. R. Feldpausch ◽

...

Keyword(s):

Vegetation Structure ◽

Amazon Basin ◽

Vegetation Type ◽

Critical Role ◽

Leaf Traits ◽

Structure And Function ◽

Mean Annual Precipitation ◽

Exchangeable Cation ◽

Canopy Area ◽

And Function

Abstract. Sampling along a precipitation gradient in tropical South America extending from ca. 0.8 to 2.0 m a−1, savanna soils had consistently lower exchangeable cation concentrations and higher C / N ratios than nearby forest plots. These soil differences were also reflected in canopy averaged leaf traits with savanna trees typically having higher leaf mass per unit area but lower mass-based nitrogen (Nm) and potassium (Km). Both Nm and Km also increased with declining mean annual precipitation (PA), but most area-based leaf traits such as leaf photosynthetic capacity showed no systematic variation with PA or vegetation type. Despite this invariance, when taken in conjunction with other measures such as mean canopy height, area-based soil exchangeable potassium content, [K]sa , proved to be an excellent predictor of several photosynthetic properties (including 13C isotope discrimination). Moreover, when considered in a multivariate context with PA and soil plant available water storage capacity (θP) as covariates, [K]sa also proved to be an excellent predictor of stand-level canopy area, providing drastically improved fits as compared to models considering just PA and/or θP. Neither calcium, nor magnesium, nor soil pH could substitute for potassium when tested as alternative model predictors (ΔAIC > 10). Nor for any model could simple soil texture metrics such as sand or clay content substitute for either [K]sa or θP. Taken in conjunction with recent work in Africa and the forests of the Amazon Basin, this suggests – in combination with some newly conceptualised interacting effects of PA and θP also presented here – a critical role for potassium as a modulator of tropical vegetation structure and function.

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The Laryngeal Epithelium in Reflux

Perspectives on Voice and Voice Disorders ◽

10.1044/vvd21.3.112 ◽

2011 ◽

Vol 21 (3) ◽

pp. 112-117 ◽

Cited By ~ 2

Author(s):

Elizabeth Erickson-Levendoski ◽

Mahalakshmi Sivasankar

Keyword(s):

Laryngopharyngeal Reflux ◽

Critical Role ◽

Structure And Function ◽

Laryngeal Disease ◽

Health And Disease ◽

And Function ◽

The Impact

The epithelium plays a critical role in the maintenance of laryngeal health. This is evident in that laryngeal disease may result when the integrity of the epithelium is compromised by insults such as laryngopharyngeal reflux. In this article, we will review the structure and function of the laryngeal epithelium and summarize the impact of laryngopharyngeal reflux on the epithelium. Research investigating the ramifications of reflux on the epithelium has improved our understanding of laryngeal disease associated with laryngopharyngeal reflux. It further highlights the need for continued research on the laryngeal epithelium in health and disease.

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Faculty Opinions recommendation of Critical role of cyclophilin A and its prolyl-peptidyl isomerase activity in the structure and function of the hepatitis C virus replication complex.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1162955.623591 ◽

2009 ◽

Author(s):

Teresa Compton

Keyword(s):

Hepatitis C Virus ◽

Hepatitis C ◽

Virus Replication ◽

Critical Role ◽

Cyclophilin A ◽

Structure And Function ◽

Replication Complex ◽

Isomerase Activity ◽

And Function

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Critical Role of Zinc Ion on E. coli Glutamyl-Queuosine-tRNAAsp Synthetase (Glu-Q-RS) Structure and Function

The Protein Journal ◽

10.1007/s10930-014-9546-1 ◽

2014 ◽

Vol 33 (2) ◽

pp. 143-149 ◽

Cited By ~ 2

Author(s):

Sutapa Ray ◽

Victor Banerjee ◽

Mickael Blaise ◽

Baisakhi Banerjee ◽

Kali Pada Das ◽

...

Keyword(s):

Critical Role ◽

Zinc Ion ◽

Structure And Function ◽

E Coli ◽

And Function

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Impacts and Recovery of the Deepwater Horizon Oil Spill on Vegetation Structure and Function of Coastal Salt Marshes in the Northern Gulf of Mexico

Environmental Science & Technology ◽

10.1021/es203552p ◽

2012 ◽

Vol 46 (7) ◽

pp. 3737-3743 ◽

Cited By ~ 156

Author(s):

Qianxin Lin ◽

Irving A. Mendelssohn

Keyword(s):

Gulf Of Mexico ◽

Oil Spill ◽

Salt Marshes ◽

Vegetation Structure ◽

Deepwater Horizon ◽

Structure And Function ◽

Deepwater Horizon Oil Spill ◽

Northern Gulf Of Mexico ◽

Coastal Salt Marshes ◽

And Function

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Review on various factors responsible for neurodegenerative disorders

GSC Biological and Pharmaceutical Sciences ◽

10.30574/gscbps.2021.16.1.0203 ◽

2021 ◽

Vol 16 (1) ◽

pp. 126-132

Author(s):

Harshwardhan J Tembhurnikar ◽

Neha D Thool ◽

Rasika J Patil ◽

Ranjita K Das

Keyword(s):

Oxidative Stress ◽

Nervous System ◽

Neurodegenerative Disorders ◽

Protein Misfolding ◽

Critical Role ◽

Structure And Function ◽

Neuronal Structure ◽

Pathophysiological Mechanisms ◽

Neurological Illnesses ◽

And Function

Neurodegenerative disorders are nervous system disorders that result in the loss of neuronal structure and function. As shown in Alzheimer's and Parkinson's disease, these changes cause a loss of various capacities, including cognition and mobility. Several factors have been discovered to play a critical role in the etiology of common neurological illnesses, including oxidative stress and protein misfolding. It's still unclear if these factors cause or contribute to the progression of the illnesses. Despite efforts to understand the molecular and pathophysiological mechanisms behind these pathways, many aspects remain unknown. The goal of this review is to investigate the numerous factors linked to neurodegeneration.

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Current understanding of thalamic structure and function in migraine

Cephalalgia ◽

10.1177/0333102418791595 ◽

2018 ◽

Vol 39 (13) ◽

pp. 1675-1682 ◽

Cited By ~ 17

Author(s):

Samaira Younis ◽

Anders Hougaard ◽

Rodrigo Noseda ◽

Messoud Ashina

Keyword(s):

Drug Target ◽

Critical Role ◽

Structure And Function ◽

Pain Modulation ◽

Clinical Implications ◽

Important Position ◽

Cortical Regions ◽

And Function ◽

Thalamic Structure

Objective To review and discuss the literature on the role of thalamic structure and function in migraine. Discussion The thalamus holds an important position in our understanding of allodynia, central sensitization and photophobia in migraine. Structural and functional findings suggest abnormal functional connectivity between the thalamus and various cortical regions pointing towards an altered pain processing in migraine. Pharmacological nociceptive modulation suggests that the thalamus is a potential drug target. Conclusion A critical role for the thalamus in migraine-related allodynia and photophobia is well established. Additionally, the thalamus is most likely involved in the dysfunctional pain modulation and processing in migraine, but further research is needed to clarify the exact clinical implications of these findings.

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Structure of nonstructural protein 1 from SARS-CoV-2.

Journal of Virology ◽

10.1128/jvi.02019-20 ◽

2020 ◽

Author(s):

Lauren K. Clark ◽

Todd J. Green ◽

Chad M. Petit

Keyword(s):

Crystal Structure ◽

Life Cycle ◽

High Resolution ◽

Nonstructural Protein ◽

Critical Role ◽

Viral Life Cycle ◽

Structure And Function ◽

Future Studies ◽

Nonstructural Protein 1 ◽

And Function

The periodic emergence of novel coronaviruses (CoVs) represents an ongoing public health concern with significant health and financial burden worldwide. The most recent occurrence originated in the city of Wuhan, China where a novel coronavirus (SARS-CoV-2) emerged causing severe respiratory illness and pneumonia. The continual emergence of novel coronaviruses underscores the importance of developing effective vaccines as well as novel therapeutic options that target either viral functions or host factors recruited to support coronavirus replication. The CoV nonstructural protein 1 (nsp1) has been shown to promote cellular mRNA degradation, block host cell translation, and inhibit the innate immune response to virus infection. Interestingly, deletion of the nsp1-coding region in infectious clones prevented the virus from productively infecting cultured cells. Because of nsp1’s importance in the CoV life cycle, it has been highlighted as a viable target for both antiviral therapy and vaccine development. However, the fundamental molecular and structural mechanisms that underlie nsp1 function remain poorly understood, despite its critical role in the viral life cycle. Here we report the high-resolution crystal structure of the amino, globular portion of SARS-CoV-2 nsp1 (residues 10 – 127) at 1.77 Å resolution. A comparison of our structure with the SARS-CoV-1 nsp1 structure reveals how mutations alter the conformation of flexible loops, inducing the formation of novel secondary structural elements and new surface features. Paired with the recently published structure of the carboxyl end of nsp1 (residues 148 – 180), our results provide the groundwork for future studies focusing on SARS-CoV-2 nsp1 structure and function during the viral life cycle. IMPORTANCE The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is the causative agent for the COVID-19 pandemic. One protein known to play a critical role in the coronavirus life cycle is nonstructural protein1 (nsp1). As such, it has been highlighted in numerous studies as a target for both the development of antivirals and for the design of live-attenuated vaccines. Here we report the high-resolution crystal structure of nsp1 derived from SARS-CoV-2 at 1.77 Å resolution. This structure will facilitate future studies focusing on understanding the relationship between structure and function for nsp1. In turn, understanding these structure-function relationships will allow nsp1 to be fully exploited as a target for both antiviral development and vaccine design.

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Sociology

Urban Health ◽

10.1093/oso/9780190915858.003.0020 ◽

2019 ◽

pp. 188-197

Author(s):

Lei Jin ◽

Chenyu Ye ◽

Eric Fong

Keyword(s):

Urban Health ◽

Critical Role ◽

Well Being ◽

Ethnic Relations ◽

Structure And Function ◽

Urban Environments ◽

Racial And Ethnic Relations ◽

And Function ◽

Development Structure ◽

Health And Well Being

Sociology is perhaps best seen classically as the study of the development, structure, and function of human societies, and sociologists have long been interested in urbanization and the ways in which urban living influences people’s health and well-being. These interests intersect with other core sociological concerns, such as socioeconomic inequality, racial and ethnic relations, migration, social cohesion, and social control to inform unique sociological perspectives on urban health. Urban environments, bringing together heterogeneous populations in dynamic, rapidly evolving settings, are natural laboratories for understanding human societies, thus suggesting a critical role for sociological perspectives in the study of urban health. This chapter introduces a sociological lens to the study of urban health, offering how sociology can advance our understanding of the health of urban populations.

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