Xanthomonas vasicola pv. vasculorum (bacterial leaf streak of corn).

2021 ◽  
Author(s):  
Lindsay Triplett ◽  
Ravikumar Patel
Keyword(s):  
South Africa ◽  
Bacterial Pathogen ◽  
Plant Productivity ◽  
Effective Control ◽  
Control Methods ◽  
Bacterial Leaf Streak ◽  
The Usa ◽  
The Subject ◽  
Active Research ◽  
Impact Data

Abstract Xanthomonas vasicola pv. vasculorum (Xvv) is a bacterial pathogen that causes both bacterial leaf streak of maize and sugarcane gumming disease. After decades limited to South Africa, bacterial leaf streak of maize spread rapidly through maize-growing areas of Argentina, Brazil and the USA since 2014. The origin, method and biological underpinnings of this sudden spread are not well understood but are the subject of active research. Effective control methods remain elusive, but sanitation and crop debris management may limit the disease. Yield impact data are not yet available, but lesions may become severe enough to limit plant productivity in some varieties. The pathogen is not currently considered a quarantine threat by the USDA, EPPO or IPPC.

scholarly journals Xanthomonas vasicola pv. vasculorum (bacterial leaf streak of corn).

2021 ◽  
Author(s):  
Lindsay Triplett ◽  
Ravikumar Patel
Keyword(s):  
Bacterial Pathogen ◽  
Effective Control ◽  
Control Methods ◽  
Bacterial Leaf Streak ◽  
Xanthomonas Species ◽  
The Usa ◽  
The Subject ◽  
Active Research ◽  
Impact Data ◽  
Taxonomic Tree

Abstract Xanthomonas vasicola pv. vasculorum (Xvv) is a bacterial pathogen that causes both bacterial leaf streak of maize and sugarcane gumming disease. After decades limited to South Africa, bacterial leaf streak of maize spread rapidly through maize-growing areas of Argentina, Brazil and the USA since 2014. The origin, method and biological underpinnings of this sudden spread are not well understood but are the subject of active research. Effective control methods remain elusive, but sanitation and crop debris management may limit the disease. Yield impact data are not yet available, but lesions may become severe enough to limit plant productivity in some varieties. The pathogen is not currently considered a quarantine threat by the USDA, EPPO or IPPC. Taxonomic Tree Top of page Domain: Bacteria Phylum: Proteobacteria Class: Gammaproteobacteria Order: Xanthomonadales Family: Xanthomonadaceae Genus: Xanthomonas Species: Xanthomonas vasicola pv. vasculorum Notes on Taxonomy and Nomenclature Top of page The taxonomic nomenclature of the pathogen has undergone several changes and is still being resolved at the time of this report. The Xanthomonas clade causing.

scholarly journals A Review of Alternative Management Tactics Employed for the Control of Various Cockroach Species (Order: Blattodea) in the USA

Insects ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 550
Author(s):  
Ameya D. Gondhalekar ◽  
Arthur G. Appel ◽  
Gretchen M. Thomas ◽  
Alvaro Romero
Keyword(s):  
Applied Research ◽  
Research Effort ◽  
Effective Control ◽  
Control Methods ◽  
Alternative Tactics ◽  
Alternative Control ◽  
The Public ◽  
Concurrent Use ◽  
The Usa ◽  
Alternative Control Methods

Effective control of domestic and peridomestic cockroaches requires integrated approaches that emphasize concurrent use of chemicals with alternative control tactics. An integrated pest management (IPM) approach is particularly justified in environments where satisfactory cockroach control cannot be achieved due to multiple factors including development of insecticide aversion and resistance in some cockroach species, and poor sanitation or structural issues that foster infestations. While a flurry of research effort has been devoted to study alternative tactics for cockroach control, only a few of them have been evaluated in the context of IPM programs. This review focuses on examining studies on alternative tactics that are proven efficacious, economical, and logistically feasible for their inclusion in IPM programs for important domestic and peridomestic cockroaches in the USA. Management programs that educate the public on cockroach biology, behavior, and the importance of sanitation; use of traps to monitor infestation levels; apply targeted low impact insecticides such as baits, have demonstrated a greater success for effective and sustainable control of cockroaches when compared to an insecticide-only approach. Incorporation of other alternative control methods to IPM programs will require more applied research that validates their use in real-world scenarios and demonstrates their cost-effectiveness.

scholarly journals A Bibliometric Review of the Keap1/Nrf2 Pathway and its Related Antioxidant Compounds

Antioxidants ◽  
2019 ◽  
Vol 8 (9) ◽  
pp. 353 ◽  
Author(s):  
Ana Paunkov ◽  
Dionysios V. Chartoumpekis ◽  
Panos G. Ziros ◽  
Gerasimos P. Sykiotis
Keyword(s):  
Web Of Science ◽  
Research Field ◽  
Antioxidant Compounds ◽  
Nrf2 Pathway ◽  
The Past ◽  
Reverse Pattern ◽  
The Usa ◽  
Bibliometric Review ◽  
The Subject ◽  
Active Research

Nrf2 is a master transcriptional regulator of antioxidant and cytoprotective pathways. Currently in its third decade, research on Nrf2 has expanded to encompass not only basic but also clinical studies. In the present bibliometric review, we employed the VOSviewer tool to describe the existing Nrf2 literature landscape. As of July 2019, 11,931 papers on Nrf2 were listed in the “Web of Science” database, with more than 1000 new papers published each year. As expected, terms related to oxidative stress and antioxidant molecules occur very often in the Nrf2 literature throughout the years. Interestingly, there is also a gradual increase in the occurrence of terms related to diseases or to natural compounds, the most prominent being sulforaphane, curcumin, and resveratrol that modulate the Nrf2 pathway. Going beyond molecular biology/biochemistry and related fields, Nrf2 research has begun to spread into more clinical areas like endocrinology/metabolism, cardiology, and nephrology, likely reflecting an increased interest in clinical applications of Nrf2 pathway activators. China has become the most prolific producer of Nrf2 papers the last five years followed by the USA and Japan, a reverse pattern compared to the past. In conclusion, Nrf2 is the subject of a globally active research field that keeps growing and extends from bench to bedside.

scholarly journals Survivor syndrome: Effects on middle managers in South Africa

1999 ◽  
Vol 2 (3) ◽  
pp. 390-406 ◽  
Author(s):  
R. Wiesner ◽  
L. P. Vermeulen ◽  
C. R. Littler
Keyword(s):  
South Africa ◽  
South African ◽  
Middle Managers ◽  
Survivor Syndrome ◽  
The Usa ◽  
African Context ◽  
The Subject ◽  
American Research ◽  
The Impact ◽  
Intense Research

The impact of organisational downsizing on employees who remain has been the subject of intense research, particularly in the USA. The issue of so-called survivor syndrome is critically important in relation to productivity growth and the success of restructuring. However, current conceptualisation has been based largely on American research. There has been little data on downsizing in the South African context. The purpose of this article is to discuss the extent of survivor syndrome in organisations that have restructured and downsized in South Africa. We ask the questions: does downsizing inevitably result in high levels of survivor syndrome; which factors intensify and modify survivor syndrome; and is there a restructuring cycle? The database constitutes 421 South African organisations.

scholarly journals Consumer dissatisfaction: Does the consumer seek redress?

1984 ◽  
Vol 15 (3) ◽  
pp. 179-181
Author(s):  
L. F. Pitt ◽  
R. Abratt
Keyword(s):  
South Africa ◽  
Health Care ◽  
South African ◽  
Word Of Mouth ◽  
Brand Management ◽  
Brand Switching ◽  
The Usa ◽  
Consumer Dissatisfaction ◽  
Successful Technique ◽  
The Subject

Consumer dissatisfaction and redress needs have been the subject of a number of research studies in the USA. The same cannot be said for South Africa. This article reports the findings of research into the South African consumer's dissatisfaction with beauty and health-care products and her actions in seeking redress. Utilizing a successful technique developed by Diener and Greyser, extent of product use, product problems, degree of dissatisfaction, and action in seeking redress are examined. The article concludes that general dissatisfaction with the products concerned is low, but that the problems are of little importance to the consumer. She is also lax in seeking redress, and expects a more positive reaction from the manufacturer than the retailer, although the sample were not inclined to seek redress from the manufacturer. It is apparent that the consumer seeks redress in the easiest alternative - brand switching, and also by means of word-of-mouth. The implications for brand management and product policy are obvious.

scholarly journals Boundaries of solidarity: a meta-ethnography of mask use during past epidemics to inform SARS-CoV-2 suppression

2021 ◽  
Vol 6 (1) ◽  
pp. e004068
Author(s):  
Po Man Tsang ◽  
Audrey Prost
Keyword(s):  
South Africa ◽  
Risk Perception ◽  
Healthcare Access ◽  
Individual Responsibility ◽  
Trust In Government ◽  
Political Leaders ◽  
Collective Levels ◽  
The Social ◽  
Social Meanings ◽  
The Usa

BackgroundMany countries aiming to suppress SARS-CoV-2 recommend the use of face masks by the general public. The social meanings attached to masks may influence their use, but remain underinvestigated.MethodsWe systematically searched eight databases for studies containing qualitative data on public mask use during past epidemics, and used meta-ethnography to explore their social meanings. We compared key concepts within and across studies, then jointly wrote a critical synthesis.ResultsWe found nine studies from China (n=5), Japan (n=1), Mexico (n=1), South Africa (n=1) and the USA (n=1). All studies describing routine mask use during epidemics were from East Asia. Participants identified masks as symbols of solidarity, civic responsibility and an allegiance to science. This effect was amplified by heightened risk perception (eg, during SARS in 2003), and by seeing masks on political leaders and in outdoor public spaces. Masks also acted as containment devices to manage threats to identity at personal and collective levels. In China and Japan, public and corporate campaigns framed routine mask use as individual responsibility for disease prevention in return for state- or corporate-sponsored healthcare access. In most studies, mask use waned as risk perception fell. In contexts where masks were mostly worn by patients with specific diseases (eg, for patients with tuberculosis in South Africa), or when trust in government was low (eg, during H1N1 in Mexico), participants described masks as stigmatising, uncomfortable or oppressive.ConclusionFace masks can take on positive social meanings linked to solidarity and altruism during epidemics. Unfortunately, these positive meanings can fail to take hold when risk perception falls, rules are seen as complex or unfair, and trust in government is low. At such times, ensuring continued use is likely to require additional efforts to promote locally appropriate positive social meanings, simplifying rules for use and ensuring fair enforcement.

Peanut Web Blotch: I. Cultural Characteristics and Identity of Causal Fungus1

1984 ◽  
Vol 11 (2) ◽  
pp. 109-114 ◽  
Author(s):  
R. A. Taber ◽  
R. E. Pettit ◽  
G. L. Philley
Keyword(s):  
South Africa ◽  
Cultural Studies ◽  
Mycelial Growth ◽  
Fungal Species ◽  
Optimum Temperature ◽  
Cultural Characteristics ◽  
Foliar Disease ◽  
The Usa

Abstract A foliar disease of peanuts, previously unreported in the USA, was found in Texas in 1972. The pathogen was identified as a species of Ascochyta. Further cultural studies have revealed this fungus to be Phoma arachidicola Marasas, Pauer, and Boerema. Pycnidia form profusely at 20 C and 25 C. Pycnidiospores are borne on short pycnidiosphores and are predominantly one-celled in culture. Spores produced in pycnidia on infected leaflets become 1 septate. Large 1-septate spores, as well as an occasional 2-septate spore, may form in culture. Optimum temperature for mycelial growth in 20 C; little or no growth occurs at 5 C or above 30 C. The teleomorphic state develops in the field on fallen leaflets and can be induced to form in the laboratory on sterilized peanut leaflets between 15 and 20 C. Cultures derived from single ascospores form pseudothecia. Pycnidiospores, ascospores, and chlamydospores are all infective units. Because this fungus produces hyaline ascospores and pseudoparaphyses, it has been transferred to the genus Didymella as Didymella arachidicola (Choch.) comb. nov. Comparisons with 15 isolates causing web blotch of peanut in the USA, Argentina, and South Africa indicate that web blotch symptoms are produced by the same fungal species.

The Israeli–Lebanese war of 2006: consequences for Lebanon

2008 ◽  
Vol 1 (2) ◽  
pp. 187-210
Author(s):  
Ziad Hafez
Keyword(s):  
Arab Countries ◽  
The Political ◽  
National Unity ◽  
Major Consequence ◽  
Political Narrative ◽  
Defence Policy ◽  
Before And After ◽  
The Usa ◽  
The Subject ◽  
The Impact

This article focuses on the political narrative in Lebanon before and after the Israeli war against Lebanon in 2006. It revolves around the subject of national unity as a sine qua non condition for success for the Lebanese resistance led by Hezbollah. A major consequence of the narrative on national unity is the need to build a modern state and establish a cohesive defence policy. The paper also examines the impact of the war on Lebanon's economy and on its relations with the rest of the world (the USA, France, Syria, Arab countries, and Iran).

Psychometric Testing as an Unfair Labour Practice

1986 ◽  
Vol 16 (3) ◽  
pp. 79-86 ◽  
Author(s):  
J.M. Taylor ◽  
E.J. Radford
Keyword(s):  
South Africa ◽  
Ethnic Groups ◽  
Test Scores ◽  
Psychometric Testing ◽  
Moderator Variable ◽  
Ability Test ◽  
Labour Relations ◽  
Ability Tests ◽  
Labour Practice ◽  
The Usa

The concept of unfair labour practice has been introduced into South Africa through the Labour Relations Act and it is argued that certain psychometric testing practices can be interpreted as falling under the definition of an unfair labour practice. Empirical results are presented indicating that different ethnic groups obtain significantly different mean ability test scores. A case-study is cited to show that this would result in underprediction of performance on a criterion for the lower scoring of two groups if test scores are regarded as comparable. It is argued that any interpretation of psychometric data in South Africa that does not take account of possible differences between ethnic groups is likely to ignore a significant moderator variable, given the history of ethnically based discriminatory practices in this country. Arguments based on meta-analytical research in the USA, to the effect that psychometric ability tests do not discriminate unfairly against disadvantaged groups if the same tests and norms are used, should not be assumed to hold in South Africa. Various conceptions of what constitutes fairness in selection are considered, and it is concluded that there is a need for employers to make explicit in their selection policies the trade-off between economic and social costs of employment practices. Finally, some implications for users of psychometric tests in industry are considered, in order to forewarn of likely developments in this field.

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