scholarly journals The role of plant secondary metabolites in mammalian herbivory: ecological perspectives

2005 ◽  
Vol 64 (1) ◽  
pp. 123-131 ◽  
Author(s):  
Glenn Iason
Keyword(s):  
Secondary Metabolites ◽  
Plant Secondary Metabolites ◽  
Kinetic Studies ◽  
Experimental Models ◽  
Food Type ◽  
Feedback Signal ◽  
Negative Effects ◽  
Positive Effects ◽  
Efficient Protection

Plant secondary metabolites (PSM) have many ecological functions, but have long been considered as defences against pathogens or herbivores (vertebrate or invertebrate), reducing the likelihood and extent of attack. However, mammalian herbivores ingest many foods containing PSM and use both behavioural methods and physiological strategies to limit their negative effects. Most physiological counter-adaptations are inducible in response to ingested PSM, providing efficient protection against toxic effects. Possible positive effects of PSM include antioxidant and anthelminthic properties and complex formation between protein and condensed tannins that protects dietary protein from degradation by the symbiotic microflora of foregut fermenters, increasing its utilisation by the animal. This protein effect is probably only beneficial to animals under a narrow range of nutrient-rich conditions found mainly in agricultural systems. There are many examples of PSM causing food avoidance or reducing food intake, but there is as yet relatively little evidence for positive selection of them by herbivores. Although the feedback mechanisms relating the post-ingestive consequences of PSM to subsequent foraging behaviour are beginning to be understood, knowledge of the integration of behavioural and physiological strategies for regulating the effects of PSM is relatively poor. The opportunities for learned avoidance of PSM may be restricted in animals with complex diets that cannot associate a particular feedback signal with a given food type. A greater emphasis on the study of subclinical effects of PSM rather than acute effects, on pharmaco-kinetic studies in relation to behavioural studies and on the use of realistic experimental models is advocated.

scholarly journals Effects of Employee Sickness Presence on Customer Repurchase and Recommendation Intentions: The Role of Customer Affective Reactions

2021 ◽  
Author(s):  
Carolin Dietz ◽  
Hannes Zacher
Keyword(s):  
Service Sector ◽  
Productivity Loss ◽  
Phone Call ◽  
Negative Effects ◽  
Disease Avoidance ◽  
Positive Effects ◽  
Sickness Presence ◽  
Organizational Consequences ◽  
Health Deterioration

AbstractSickness presence can have important individual and organizational consequences, such as health deterioration or productivity loss. Additional risks, such as negative customer reactions, may be particularly relevant in the service sector. Based on affective events theory and appraisal theories, we hypothesize that employee sickness presence negatively impacts customer repurchase and recommendation intentions. Furthermore, we explore potential affective mechanisms of these effects, including disease avoidance, personal anger, moral outrage, post-consumption guilt, and customer compassion for the employee. We conducted four studies, including three experimental vignette methodology studies (Ns = 227, 72, and 763) and a qualitative study (N = 54). In Study 1, employee sickness presence had negative effects on repurchase and recommendation intentions. Results of Study 2 show that customers experienced disgust, fear, anger, guilt, compassion, and indifference in response to sickness presence. In Study 3, anger explained the negative effects of employee sickness presence on repurchase and recommendation intentions, while appraisals of moral fairness were negatively related to both customer intentions. Finally, in Study 4, disgust and anger explained negative effects, while fear, guilt, and compassion explained positive effects of employee sickness presence on customer intentions. Appraisals of goal incongruence, reduced agency of the customer, and uncertainty were negatively related to customer intentions. The physical absence of the customer in the service encounter (phone call) mitigated the experience of disgust, fear, and anger, whereas it exacerbated feelings of compassion for the ill employee.

The effect of consumers' religiosity on consumer ethics: the mediating role of ethical ideology

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Denni Arli ◽  
Fandy Tjiptono
Keyword(s):  
Consumer Ethics ◽  
Ethical Ideology ◽  
Negative Effects ◽  
Content Type ◽  
Mediating Role ◽  
Positive Effects ◽  
Central Java ◽  
Consumer Ethics Scale ◽  
The Impact

PurposeReligious doctrines generally encourage people to behave ethically. However, in daily life, individuals notice inconsistencies between religious beliefs and behavior, leading them to ask, in the context of commerce, why religious consumers would behave unethically. The purpose of this study was to investigate the impact of consumers' intrinsic and extrinsic religiosity on their ethical behavior. Specifically, the moderating effect of ethical ideology on the relationship between Indonesian consumers' religiosity and their ethics was examined by means of a survey.Design/methodology/approachThe data derived from the questionnaire were complemented by convenience samples of Indonesians living in Daerah Istimewa Yogyakarta (DIY) in central Java. The researchers distributed 600 questionnaires in two major shopping malls and several housing areas in the region, of which 467 were completed and returned, for an overall response rate of 77.8%.FindingsThe results indicated that the participants' intrinsic religiosity negatively impacted their ethical beliefs and was mediated by their idealistic ethical ideology. The present study also found that idealism had negative effects on three of the four dimensions of the consumer ethics scale (CES) (actively benefiting, passively benefiting and questionable behavior), while relativism had positive effects on two of the dimensions (passively benefiting and questionable behavior.Research limitations/implicationsOne limitation of the present study was that the analysis did not distinguish among the religions practiced by the respondents to the questionnaire.Originality/valueThis is one of the first few studies investigating the mediating role of ethical ideology in a religious society. This study contributes to the literature on these issues in theoretical and managerial terms by extending the Hunt-Vitell theory (1986) to the context of consumer ethics.

Role of Stress and Defense in Plant Secondary Metabolites Production

2020 ◽  
pp. 151-195
Author(s):  
Humberto Aguirre-Becerra ◽  
Ma Cristina Vazquez-Hernandez ◽  
Diana Saenz de la O ◽  
Aurora Alvarado-Mariana ◽  
Ramon G. Guevara-Gonzalez ◽  
...  
Keyword(s):  
Secondary Metabolites ◽  
Plant Secondary Metabolites ◽  
Metabolites Production

Phytoremediation of Electronic Waste: A Mechanistic Overview and Role of Plant Secondary Metabolites

2019 ◽  
pp. 233-252 ◽  
Author(s):  
Mubarak Ali Khan ◽  
Nazif Ullah ◽  
Tariq Khan ◽  
Muhsin Jamal ◽  
Naseer Ali Shah ◽  
...  
Keyword(s):  
Secondary Metabolites ◽  
Electronic Waste ◽  
Plant Secondary Metabolites

scholarly journals Accessibility and attractiveness of primary care services in Algeria: Models of spatial interaction of the NHPF of the Eastern Health Region

2017 ◽  
Vol 1 (2) ◽  
pp. 24-34
Author(s):  
Nasreddine AISSAOUI ◽  
Said BRIKA
Keyword(s):  
Spatial Interaction ◽  
Eastern Health ◽  
Negative Effects ◽  
Positive Effects ◽  
Care Services ◽  
Primary Care Services ◽  
Eastern Algeria ◽  
The One ◽  
Financial Allocation

The restructuring of basic health care structures represented by public institutions nearby care in Algeria, according to Executive Decree 07/140 of 19 May 2007, could have effects both positive and negative: positive effects as we quote the approximation of diversified health services towards the citizen. As for the negative effects they live in ignorance of the real role of this kind of structure, namely the prevention in the broad sense of the term before the one of care. Among the results of our case study on the 7 wilayas of eastern Algeria, we noted: a small financial allocation and a shortage of medical and paramedical human resources, which have frozen the role of these NHPF, and which have favored the caregiver’s recourse to hospital emergencies. On the other hand, we have also noticed the sufficient number of these structures throughout all the communes of the country and their proximity to the living environments, despite the derisory number of services rendered, which were able to meet certain needs of the inhabitants.

scholarly journals Title Page Title: The role of DNA methylation in the accumulation of iridoid glycosides in Rehmannia glutinosa

2021 ◽  
Author(s):  
Tianyu Dong ◽  
Xiaoyan Wei ◽  
Qianting Qi ◽  
Peilei Chen ◽  
Yanqing Zhou ◽  
...  
Keyword(s):  
Gene Expression ◽  
Dna Methylation ◽  
Secondary Metabolites ◽  
Iridoid Glycosides ◽  
Methylation Status ◽  
Plant Secondary Metabolites ◽  
Dna Demethylation ◽  
Terpene Biosynthesis ◽  
The Relationship

Abstract Background: Epigenetic regulation plays a significant role in the accumulation of plant secondary metabolites. The terpenoids are the most abundant in the secondary metabolites of plants, iridoid glycosides belong to monoterpenoids which is one of the main medicinal components of R.glutinosa. At present, study on iridoid glycosides mainly focuses on its pharmacology, accumulation and distribution, while the mechanism of its biosynthesis and the relationship between DNA methylation and plant terpene biosynthesis are seldom reports. Results: The research showed that the expression of DXS, DXR, 10HGO, G10H, GPPS and accumulation of iridoid glycosides increased at first and then decreased with the maturity of R.glutinosa, and under different concentrations of 5-azaC, the expression of DXS, DXR, 10HGO, G10H, GPPS and the accumulation of total iridoid glycosides were promoted, the promotion effect of low concentration (15μM-50μM) was more significant, the content of genomic DNA 5mC decreased significantly, the DNA methylation status of R.glutinosa genomes was also changed. DNA demethylation promoted gene expression and increased the accumulation of iridoid glycosides, but excessive demethylation inhibited gene expression and decreased the accumulation of iridoid glycosides. Conclusion: The analysis of DNA methylation, gene expression, and accumulation of iridoid glycoside provides insights into accumulation of terpenoids in R.glutinosa and lays a foundation for future studies on the effects of epigenetics on the synthesis of secondary metabolites.

Embracing supply base complexity: the contingency role of strategic purchasing

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Melek Akın Ateş ◽  
Huriye Memiş
Keyword(s):  
Performance Criteria ◽  
Measurement Properties ◽  
Hierarchical Regression ◽  
Structured Interviews ◽  
Negative Effects ◽  
Content Type ◽  
Strategic Purchasing ◽  
Positive Effects ◽  
Confirmatory Factor

PurposeThis paper aims to empirically examine the moderating role of strategic purchasing on the relationship between supply base complexity (SBC) and purchasing performance.Design/methodology/approachSurvey data were collected from 209 firms listed in the Capital Top 500 Firms of Turkey. Measurement properties were assessed via confirmatory factor analysis, and the conceptual model was tested via hierarchical regression analysis. A supplementary analysis based on 14 semi-structured interviews was conducted to provide further insights on the survey findings.FindingsRegarding structural SBC, the results suggest that horizontal complexity and supplier interaction improve purchasing performance, but only in firms with high strategic purchasing. By contrast, spatial complexity reduces purchasing performance in firms with high strategic purchasing, while supplier differentiation does not have any effect. Regarding dynamic SBC, the results show that both delivery complexity and supplier instability reduce purchasing performance when firms have low strategic purchasing. Interviews further suggest that firms with high strategic purchasing leverage the positive effects and mitigate the negative effects of SBC by having a long-term focus, considering multiple performance criteria and adopting advanced purchasing practices.Practical implicationsIn contrast to what is widely posited in the existing literature, the nuanced findings of this study reveal that complexity is not always detrimental. The results suggest that practitioners should aim for high levels of strategic purchasing to suppress the negative effects of SBC while leveraging its benefits.Originality/valueBy investigating the contingency role of strategic purchasing, this study provides novel insights into the under-investigated issue of how to best “manage” SBC.

scholarly journals Plant secondary metabolites: antiparasitic effects and their role in ruminant production systems

2004 ◽  
Vol 63 (4) ◽  
pp. 631-639 ◽  
Author(s):  
Spiridoula Athanasiadou ◽  
Ilias Kyriazakis
Keyword(s):  
Secondary Metabolites ◽  
Production Systems ◽  
Scientific Evidence ◽  
Plant Secondary Metabolites ◽  
Antiparasitic Activity ◽  
Excessive Consumption ◽  
Therapeutic Properties ◽  
Nutritional Effects

The purported antiparasitic properties of plant secondary metabolites (PSM) have been the cause of controversy amongst the scientific community. Despite long-standing knowledge of the prophylactic and therapeutic properties of PSM-rich extracts, which comes mainly from ethnoveterinary sources, the scientific evidence of the antiparasitic effects of PSM is inconsistent. In the first part of the present paper the causes of this controversy are addressed, and the evidence available on the antiparasitic effects of PSM is critically examined. The focus is on examples of the antiparasitic activity of PSM against helminth nematodes. The conclusion is that PSM can have antiparasitic properties, which depend on their structure, level of ingestion and availability within the gastrointestinal tract of the animal. The second part is an appraisal of the potential role of PSM for parasite control in ruminant production systems. Despite their antiparasitic properties, PSM consumption does not necessarily have positive consequences in parasitised herbivores, as excessive consumption of PSM can adversely affect herbivore fitness and survival, through their anti-nutritional properties. For this reason it is suggested that the antiparasitic properties of PSM should be assessed at the same time as their anti-nutritional effects. The same measure, e.g. the performance of parasitised hosts, should be used when assessing these properties. The assessment of the costs and benefits suggests that parasitised herbivores can benefit from the long-term consumption of PSM only if the antiparasitic benefits outweigh the anti-nutritional costs of PSM. In addition, it is proposed that parasitised animals might be able to benefit from PSM consumption even if their performance is impaired, as long as the latter is a short-term compromise that leads to long-term benefits.

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