scholarly journals Soil organic nitrogen: an overlooked but potentially significant contribution to crop nutrition

2021 ◽  
Author(s):  
Soudeh Farzadfar ◽  
J. Diane Knight ◽  
Kate A. Congreves
Keyword(s):  
Analytical Techniques ◽  
Organic N ◽  
Future Research ◽  
Traditional Model ◽  
N Nutrition ◽  
Agricultural Plant ◽  
Soil Organic Nitrogen ◽  
Nutrition Research ◽  
N Assimilation ◽  
Agricultural Literature

Abstract Background For more than a century, crop N nutrition research has primarily focused on inorganic N (IN) dynamics, building the traditional model that agricultural plants predominantly take up N in the form of NO3− and NH4+. However, results reported in the ecological and agricultural literature suggest that the traditional model of plant N nutrition is oversimplified. Scope We examine the role of organic N (ON) in plant N nutrition, first by reviewing the historical discoveries by ecologists of plant ON uptake, then by discussing the advancements of key analytical techniques that have furthered the cause (stable isotope and microdialysis techniques). The current state of knowledge on soil ON dynamics is analyzed concurrently with recent developments that show ON uptake and assimilation by agricultural plant species. Lastly, we consider the relationship between ON uptake and nitrogen use efficiency (NUE) in an agricultural context. Conclusions We propose several mechanisms by which ON uptake and assimilation may increase crop NUE, such as by reducing N assimilation costs, promoting root biomass growth, shaping N cycling microbial communities, recapturing exuded N compounds, and aligning the root uptake capacity to the soil N supply in highly fertilized systems. These hypothetical mechanisms should direct future research on the topic. Although the quantitative role remains unknown, ON compounds should be considered as significant contributors to plant N nutrition.

A Short Review on Structural Equation Modeling: Applications and Future Research Directions

2015 ◽  
Vol 4 (3) ◽  
Author(s):  
Surajit Bag
Keyword(s):  
Structural Equation Modeling ◽  
Structural Equation ◽  
First Generation ◽  
Analytical Techniques ◽  
Short Review ◽  
Equation Modeling ◽  
Future Research ◽  
Multivariate Techniques ◽  
Statistical Efficiency ◽  
Future Research Directions

The application of multivariate techniques is mainly to expand the researchers explanatory ability and statistical efficiency. The first generation analytical techniques share a common limitation i.e. each technique can examine only a single relationship at a time. Structural Equation Modeling, an extension of several multivariate techniques is the technique popularly used today can examine a series of dependence relationships simultaneously. The purpose of this study is to provide a short review on Structural Equation Modeling (SEM) being used in social sciences research. A comprehensive literature review of article appearing in top journals is conducted in order to identify how often SEM theory is used. Also the key SEM steps have been provided offering potential researchers with a theoretical supported systematic approach that simplify the multiple options with performing SEM.

scholarly journals Rethinking SME default prediction: a systematic literature review and future perspectives

2021 ◽  
Author(s):  
Francesco Ciampi ◽  
Alessandro Giannozzi ◽  
Giacomo Marzi ◽  
Edward I. Altman
Keyword(s):  
Literature Review ◽  
Systematic Literature Review ◽  
Global Financial Crisis ◽  
Analytical Techniques ◽  
Future Research ◽  
Finance Management ◽  
Default Prediction ◽  
Emerging Issues ◽  
Medium Enterprise ◽  
Modern Analytical

AbstractOver the last dozen years, the topic of small and medium enterprise (SME) default prediction has developed into a relevant research domain that has grown for important reasons exponentially across multiple disciplines, including finance, management, accounting, and statistics. Motivated by the enormous toll on SMEs caused by the 2007–2009 global financial crisis as well as the recent COVID-19 crisis and the consequent need to develop new SME default predictors, this paper provides a systematic literature review, based on a statistical, bibliometric analysis, of over 100 peer-reviewed articles published on SME default prediction modelling over a 34-year period, 1986 to 2019. We identified, analysed and reviewed five streams of research and suggest a set of future research avenues to help scholars and practitioners address the new challenges and emerging issues in a changing economic environment. The research agenda proposes some new innovative approaches to capture and exploit new data sources using modern analytical techniques, like artificial intelligence, machine learning, and macro-data inputs, with the aim of providing enhanced predictive results.

A bibliometric analysis of Halal and Islamic tourism

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Syed Ahamed Suban ◽  
Kumar Madhan ◽  
Shameem Shagirbasha
Keyword(s):  
Bibliometric Analysis ◽  
Visual Analysis ◽  
Analytical Techniques ◽  
Future Research ◽  
Content Type ◽  
Concise Review ◽  
Knowledge Area ◽  
Scopus Database ◽  
Broad Subject ◽  
Number Of Authors

PurposeHalal and Islamic tourism is gaining attention in the tourism literature in recent years. This study uses bibliometric analytical techniques to explore all the publications indexed in the Scopus database in the broad subject of Halal and Islamic tourism from 2004 to 2021.Design/methodology/approachThe authors found 238 publications that fit the function, subject and set criteria. The papers were analysed in terms of publication by knowledge area, number of studies published every year, contribution by countries, number of authors and most influential journals. VOS viewer was used to perform a visual analysis on co-occurrence of keywords and document citations.FindingsAccording to the findings, the Scopus database includes 151 (34.40%) documents on business, management and accounting, and 89 (20.27%) documents on social science. It was reported that 29 documents were published in 2018, followed by 54 documents in 2019 and 56 documents in 2021. Malaysia has contributed 86 documents on Islamic tourism, whereas Indonesia has contributed 64 documents. The paper also discusses other interesting findings.Research limitations/implicationsThe bibliometric analysis carried out was confined to Scopus data. Other national and international databases were not taken into account for this research.Originality/valueBetween 2004 and 2021, this study examined relevant studies on Halal and Islamic tourism. The study presents a concise review of the literature accessible to researchers working in this area and provides recommendations for future research.

scholarly journals The formation, properties and impact of secondary organic aerosol: current and emerging issues

2009 ◽  
Vol 9 (14) ◽  
pp. 5155-5236 ◽  
Author(s):  
M. Hallquist ◽  
J. C. Wenger ◽  
U. Baltensperger ◽  
Y. Rudich ◽  
D. Simpson ◽  
...  
Keyword(s):  
Secondary Organic Aerosol ◽  
Analytical Techniques ◽  
Organic Aerosol ◽  
Future Research ◽  
Detailed Knowledge ◽  
Aerosol Formation ◽  
Organic Components ◽  
Modeling Studies ◽  
Tropospheric Aerosol ◽  
Emerging Issues

Abstract. Secondary organic aerosol (SOA) accounts for a significant fraction of ambient tropospheric aerosol and a detailed knowledge of the formation, properties and transformation of SOA is therefore required to evaluate its impact on atmospheric processes, climate and human health. The chemical and physical processes associated with SOA formation are complex and varied, and, despite considerable progress in recent years, a quantitative and predictive understanding of SOA formation does not exist and therefore represents a major research challenge in atmospheric science. This review begins with an update on the current state of knowledge on the global SOA budget and is followed by an overview of the atmospheric degradation mechanisms for SOA precursors, gas-particle partitioning theory and the analytical techniques used to determine the chemical composition of SOA. A survey of recent laboratory, field and modeling studies is also presented. The following topical and emerging issues are highlighted and discussed in detail: molecular characterization of biogenic SOA constituents, condensed phase reactions and oligomerization, the interaction of atmospheric organic components with sulfuric acid, the chemical and photochemical processing of organics in the atmospheric aqueous phase, aerosol formation from real plant emissions, interaction of atmospheric organic components with water, thermodynamics and mixtures in atmospheric models. Finally, the major challenges ahead in laboratory, field and modeling studies of SOA are discussed and recommendations for future research directions are proposed.

scholarly journals Application of Volatilome Analysis to the Diagnosis of Mycobacteria Infection in Livestock

2021 ◽  
Vol 8 ◽  
Author(s):  
Pablo Rodríguez-Hernández ◽  
Vicente Rodríguez-Estévez ◽  
Lourdes Arce ◽  
Jaime Gómez-Laguna
Keyword(s):  
Analytical Techniques ◽  
Diagnostic Techniques ◽  
Diagnostic Tools ◽  
Future Research ◽  
Control Programs ◽  
Targeted Analysis ◽  
Low Sensitivity ◽  
And Control

Volatile organic compounds (VOCs) are small molecular mass metabolites which compose the volatilome, whose analysis has been widely employed in different areas. This innovative approach has emerged in research as a diagnostic alternative to different diseases in human and veterinary medicine, which still present constraints regarding analytical and diagnostic sensitivity. Such is the case of the infection by mycobacteria responsible for tuberculosis and paratuberculosis in livestock. Although eradication and control programs have been partly managed with success in many countries worldwide, the often low sensitivity of the current diagnostic techniques against Mycobacterium bovis (as well as other mycobacteria from Mycobacterium tuberculosis complex) and Mycobacterium avium subsp. paratuberculosis together with other hurdles such as low mycobacteria loads in samples, a tedious process of microbiological culture, inhibition by many variables, or intermittent shedding of the mycobacteria highlight the importance of evaluating new techniques that open different options and complement the diagnostic paradigm. In this sense, volatilome analysis stands as a potential option because it fulfills part of the mycobacterial diagnosis requirements. The aim of the present review is to compile the information related to the diagnosis of tuberculosis and paratuberculosis in livestock through the analysis of VOCs by using different biological matrices. The analytical techniques used for the evaluation of VOCs are discussed focusing on the advantages and drawbacks offered compared with the routine diagnostic tools. In addition, the differences described in the literature among in vivo and in vitro assays, natural and experimental infections, and the use of specific VOCs (targeted analysis) and complete VOC pattern (non-targeted analysis) are highlighted. This review emphasizes how this methodology could be useful in the problematic diagnosis of tuberculosis and paratuberculosis in livestock and poses challenges to be addressed in future research.

EXPRESS: The Future of Marketing Analytics and Public Policy

2021 ◽  
pp. 074391562110423
Author(s):  
Brennan Davis ◽  
Dhruv Grewal ◽  
Steve Hamilton
Keyword(s):  
Public Policy ◽  
Policy Research ◽  
Analytical Techniques ◽  
Future Research ◽  
Social Media Analytics ◽  
Special Issue ◽  
Marketing Analytics ◽  
Future Of Marketing ◽  
And Robotics

The purpose of this special issue is to encourage the emerging role of analytics in marketing and public policy research. We draw attention to a multitude of comprehensive data sources and analytical techniques that tackle important public policy and marketing issues. We highlight six key domains that provide fruitful avenues for such pursuit: retail analytics, social media analytics, marketing mix analytics, services including healthcare, nonprofits and politics, and artificial intelligence and robotics. We also offer an overview of the various articles and commentaries that are included in this special issue, and we encourage future research building on the underlying analytics approaches, substantive findings, and theoretical discoveries.

scholarly journals Do plants use root-derived proteases to promote the uptake of soil organic nitrogen?

2020 ◽  
Vol 456 (1-2) ◽  
pp. 355-367
Author(s):  
Lucy M. Greenfield ◽  
Paul W. Hill ◽  
Eric Paterson ◽  
Elizabeth M. Baggs ◽  
Davey L. Jones
Keyword(s):  
Protease Activity ◽  
Organic Nitrogen ◽  
N Uptake ◽  
Root Surface ◽  
Organic N ◽  
Soil Organic Nitrogen ◽  
Poor Access ◽  
N Deficiency ◽  
Almost All ◽  
Soil Protein

Abstract Aims The capacity of plant roots to directly acquire organic nitrogen (N) in the form of oligopeptides and amino acids from soil is well established. However, plants have poor access to protein, the central reservoir of soil organic N. Our question is: do plants actively secrete proteases to enhance the breakdown of soil protein or are they functionally reliant on soil microorganisms to undertake this role? Methods Growing maize and wheat under sterile hydroponic conditions with and without inorganic N, we measured protease activity on the root surface (root-bound proteases) or exogenously in the solution (free proteases). We compared root protease activities to the rhizosphere microbial community to estimate the ecological significance of root-derived proteases. Results We found little evidence for the secretion of free proteases, with almost all protease activity associated with the root surface. Root protease activity was not stimulated under N deficiency. Our findings suggest that cereal roots contribute one-fifth of rhizosphere protease activity. Conclusions Our results indicate that plant N uptake is only functionally significant when soil protein is in direct contact with root surfaces. The lack of protease upregulation under N deficiency suggests that root protease activity is unrelated to enhanced soil N capture.

scholarly journals Treatment of Whiplash-Associated Disorders - Part II: Medical and Surgical Interventions

2005 ◽  
Vol 10 (1) ◽  
pp. 33-40 ◽  
Author(s):  
Anne Conlin ◽  
Sanjit Bhogal ◽  
Keith Sequeira ◽  
Robert Teasell
Keyword(s):  
Outcome Measures ◽  
Methodological Quality ◽  
Task Force ◽  
Analytical Techniques ◽  
Epidemiological Studies ◽  
Treatment Modalities ◽  
Future Research ◽  
Surgical Interventions ◽  
Radiofrequency Neurotomy

BACKGROUND: Whiplash-associated disorder (WAD) is a term used to describe injury due to an acceleration-deceleration mechanism at the neck. In 1995, the Quebec Task Force published a report that contained evidence-based recommendations regarding the treatment of WAD based on studies completed before 1993 and consensus-based recommendations.OBJECTIVE: The objective of the present article - the second installment of a two part review on WAD - is to provide a systematic review of the literature published between January 1993 and July 2003 on medical and surgical interventions for WAD using meta-analytical techniques.METHODS OF THE REVIEW: Three medical literature databases were searched for identification of all clinical trials on the treatment of WAD. Randomized controlled trials (RCTs) and epidemiological studies were categorized by treatment modality and analyzed by outcome measures. The methodological quality of the RCTs was assessed. When possible, pooled analyses of the RCTs were completed for meta-analyses of the data. The results of all the studies were compiled and systematically reviewed.RESULTS: The studies were categorized as medical or surgical interventions. A total of five RCTs and six non-RCTs were evaluated. The mean methodological quality of the RCTs was 7.3 among studies on medical interventions and 7.5 for studies on surgical intervention. Pooled analyses were completed across all treatment modalities and outcome measures. The outcomes of each study were summarized in tables.CONCLUSIONS: While several quality RCTs and epidemiological studies have been published since 1993 on medical and surgical interventions, the cumulative evidence is lacking. Moderate evidence exists in support of radiofrequency neurotomy. Evidence for steroid injections, botulinum treatments, carpal tunnel decompression and cervical discectomy is conflicting or unclear. Future research is required to clarify the utility of radiofrequency neurotomy and pulsed electromagnetic field treatment for WAD.

League Tables for Performance Improvement in Health Care

1998 ◽  
Vol 3 (1) ◽  
pp. 50-57 ◽  
Author(s):  
Sandra Nutley ◽  
Peter C. Smith
Keyword(s):  
Health Care ◽  
Health Care Providers ◽  
Analytical Techniques ◽  
Performance Data ◽  
Future Research ◽  
League Table ◽  
Care Providers ◽  
League Tables ◽  
Wide Range ◽  
The Impact

Objectives: Increasingly health care performance data are being disseminated in the form of ‘league tables' of health care providers, with the implication that such publication helps purchasers select the better providers, and spurs providers into improvements. This paper examines progress to date. Methods: Three stages of the league table process are considered: measurement, analysis and action. Results: A wide range of measurement schemes are now in place, although the emphasis has been on process variables and mortality as a measure of outcome. Several analytical techniques have been deployed to help users make sense of league tables, and to help determine the causes of variations in reported performance. The weakest aspect of current methods relates to the use to which such analysis is put. Conclusions: A haphazard approach to using league table data exists, with few reports on the impact of publication. A variety of directions for future research into the use of performance data are needed.

Multidisciplinary teams to conduct integrated research on farming systems - a challenge

Soil Research ◽  
1995 ◽  
Vol 33 (4) ◽  
pp. 659 ◽  
Author(s):  
RJ French
Keyword(s):  
Water Use Efficiency ◽  
Water Use ◽  
Systems Approach ◽  
Farming Systems ◽  
Future Research ◽  
Multidisciplinary Teams ◽  
Cooperative Effort ◽  
Soil Organic Nitrogen ◽  
Use Efficiency ◽  
Groups And Teams

This paper reviews changes in farming practices that helped farmers to reduce soil erosion, and increase water-use efficiency and yield on their specific soils and climate. The program initially involved working with Soil Conservation Boards and conducting research on farmers' properties and on research stations. This work then extended from evaluating single factor effects to assessing the combined factors limiting yield in specific crop and pasture rotations. Benchmarks were established for different soils and climates as guides for farmers to measure their success. These included yield and water use efficiency, adequate and lower limit levels of soil organic nitrogen, and the need to maintain a nutrient input-output balance to provide a sustainable agriculture. The paper highlights the need for future research to adopt an integrated systems approach to overcome the major limitations to growth. This will require a cooperative effort between farmer groups and teams of soil scientists and agronomists to conduct multifactor research in farmers' paddocks.

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