Comparative effects of mites and lice on the reproductive success of rock doves (Columba livia)

Parasitology ◽  
1995 ◽  
Vol 110 (2) ◽  
pp. 195-206 ◽  
Author(s):  
D. H. Clayton ◽  
D. M. Tompkins

SUMMARYWe report experimental data comparing the effects of Mesostigmatid mites and Ischnoceran lice on the reproductive performance of a single group of captive rock doves (Columba livia). Several components of host reproductive success were compared for the two groups, including number of eggs laid, hatching success, nestling growth rates, fledging success, post-fledging body mass and survival. Adult body mass and survival were also compared. There was a dramatic difference in the effects of the mites and lice. The former drove host reproductive success to zero, mainly by agitating adults and causing them to incubate eggs less faithfully. Nestling growth rates and post-fledging survival were also significantly reduced by mites. Lice showed no effect on reproductive success whatsoever, even though the feather damage they cause is known to have energetic consequences (Booth, Clayton & Block, 1993). Neither parasite had a significant effect on adult birds. Although Ischnocera are found on most species of birds, our results for lice constitute the first experimental test of the impact of Ischnocera on avian reproductive success (preliminary report by Clayton & Tompkins, 1994). We discuss reasons for the different effects of mites and lice, including the relationship of horizontal (mites) and vertical (lice) transmission to the evolution of virulence.

2017 ◽  
Author(s):  
James J. Anderson

AbstractThe relationship between body mass and survivorship is explained by a model that merges metabolic theory relating metabolism to body mass, and vitality theory relating survival to vitality loss and extrinsic mortality. The resulting metabolic-vitality framework hypothesizes mortality results from replicative senescence of the hematopoietic system and predator-prey interactions. Fitting the metabolic-vitality model to body mass and maximum lifespan data of 494 nonvolant mammals yields allometric relationships of body mass to the vitality parameters, from which full survivorship profiles can be predicted from body mass. Comparisons of the mass-derived vitality parameters to those estimated directly from survival data identifies how intrinsic and extrinsic mortality processes of specific populations deviate from the aggregate. Highlighted findings include a mathematical explanation for the shift from Type I to Type II survivorship curves with decreasing body mass, a quantification of the impact of hunting on wild populations and a quantification of the reduce rate of primate aging relative to the aggregate of mammal populations. Finally, the framework allows explorations of the combined effects of animal aging and predation on survival patterns.


2010 ◽  
Vol 20 (1) ◽  
pp. 3-8
Author(s):  
Dee Adams Nikjeh

Abstract Administrators and supervisors face daily challenges over issues such as program funding, service fees, correct coding procedures, and the ever-changing healthcare regulations. Receiving equitable reimbursement for speech-language pathology and audiology services necessitates an understanding of federal coding and reimbursement systems. This tutorial provides information pertaining to two major healthcare coding systems and explains the relationship of these systems to clinical documentation, the Medicare Physician Fee Schedule and equitable reimbursement. An explanation of coding edits and coding modifiers is provided for use in those occasional atypical situations when the standard use of procedural coding may not be appropriate. Also included in this tutorial is a brief discussion of the impact that the Medicare Improvements for Patients and Providers Act of 2008 (HR 6331 Medicare Improvements for Patients and Providers Act [MIPPA], 2008) has had on the valuation of speech-language pathology procedure codes.


2021 ◽  
Vol 16 (5) ◽  
pp. 1217-1230
Author(s):  
Shuchi Gupta ◽  
Nishad Nawaz ◽  
Adel Abdulmhsen Alfalah ◽  
Rana Tahir Naveed ◽  
Saqib Muneer ◽  
...  

With the advent of the Internet and other digital technologies, contemporary businesses from all sectors are using social media for communication with consumers to engage them meaningfully with a brand. However, the use of social media for corporate social responsibility (CSR) communication is relatively new to the existing literature. Likewise, the impact of CSR communication through social media (CSR-S) on consumer emotions and behavior is, to date, underexplored. To address this, the present research aims to test the relationship of CSR-S on brand admiration and consumer purchase intention. The study proposes a direct relationship between CSR-S and purchase intention with a mediating effect of brand admiration. The data were collected from the banking consumers of Pakistan through a self-administered questionnaire. The authors distributed 800 questionnaires and received 463 questionnaires useful for data analysis, so the present research study response rate was around 59%. The data were analyzed using the structural equation modeling (SEM) technique in AMOS. The results revealed that CSR-S is positively related to purchase intention (β = 0.233). The results further showed that brand admiration partially mediates this relationship (β = 0.079). The survey respondents confirmed that their bank’s CSR communication helps enhance their purchase likelihood and their feelings of admiration for their bank. These findings will help policymakers at banking institutions better understand the importance of CSR communication on different social media platforms to achieve consumer-related outcomes.


Author(s):  
Zhi Yang ◽  
Quang Van Ngo ◽  
Chung Xuan Thi Nguyen

In the era of the information-communication technology with the development of electronic commerce, consumers can buy almost everything anywhere and at any time. One of the greatest benefits of e-commerce has been the convenience and the vast choices which consumers get online. However, some serious issues exist that impede consumers from transaction online. These issues have attracted the attention of many marketing researchers in recent years. In this research, the authors focus on the impact of consumers' ethics perception of e-retailer on their purchase intention and satisfaction. The authors also try to clarify the roles of trust and commitment in the relationship of ethics on consumers purchase decision and satisfaction because of their importance in e-commerce but also the privation in the research of previous studies. The data collected from a survey of 390 online consumers in Vietnam. Results reveal that there are significant relationships between online retailers' ethics and consumers' purchase intention and satisfaction via the mediation of trust and commitment.


2015 ◽  
Vol 130 (1) ◽  
pp. 25-31 ◽  
Author(s):  
S Degeest ◽  
P Corthals ◽  
I Dhooge ◽  
H Keppler

AbstractObjective:This study aimed to determine the characteristics of tinnitus and tinnitus-related variables and explore their possible relationship with tinnitus-related handicap.Methods:Eighty-one patients with chronic tinnitus were included. The study protocol measured hearing status, tinnitus pitch, loudness, maskability and loudness discomfort levels. All patients filled in the Tinnitus Sample Case History Questionnaire, the Hyperacusis Questionnaire and the Tinnitus Handicap Inventory. The relationship of each variable with the Tinnitus Handicap Inventory score was evaluated by univariate and multivariate analyses.Results:Five univariables were associated with the Tinnitus Handicap Inventory score: loudness discomfort level, subjective tinnitus loudness, tinnitus awareness, noise intolerance and Hyperacusis Questionnaire score. Multiple regression analysis showed that the Hyperacusis Questionnaire score and tinnitus awareness were independently associated with the Tinnitus Handicap Inventory score.Conclusion:Hyperacusis and tinnitus awareness were independently associated with the Tinnitus Handicap Inventory score. Questionnaires on tinnitus and hyperacusis are especially suited to providing additional insight into tinnitus-related handicap and are therefore useful for evaluating tinnitus patients.


Author(s):  
Zulfiqar Ahmed Iqbal ◽  
Ghulam Abid ◽  
Muhammad Arshad ◽  
Fouzia Ashfaq ◽  
Muhammad Ahsan Athar ◽  
...  

This study empirically investigates the less discussed catalytic effect of personality in the relationship of leadership style and employee thriving at work. The growth and sustainability of the organization is linked with the association of leadership style and employee thriving at the worplace. The objectives of this study are to explore the impact of authoritative and laissez-faire leadership styles and the moderating role of the personality trait of conscientiousness on thriving in the workplace. A sample of 312 participants was taken from a leading school system with its branches in Lahore and Islamabad, Pakistan. The participants either worked as managers, teachers in headquarters, or school campuses, respectively. The regression results of the study show that authoritative leadership and conscientiousness have a significantly positive impact on thriving at work. Furthermore, conscientiousness moderates the relationship between laissez-faire style of leadership and thriving at work relationship. The findings of this study have theoretical implications for authoritative and laissez-faire leadership, employee conscientiousness, and managerial applications for the practitioners.


2006 ◽  
Vol 19 (5) ◽  
pp. 388-395 ◽  
Author(s):  
MAMDOUH M. SHUBAIR ◽  
POORNIMA PRABHAKARAN ◽  
VIKTORIA PAVLOVA ◽  
JAMES L. VELIANOU ◽  
ARYA M. SHARMA ◽  
...  

2021 ◽  
Vol 27 ◽  
Author(s):  
Li-Ping Yu ◽  
Ting-Ting Shi ◽  
Yan-Qin Li ◽  
Jian-Kang Mu ◽  
Ya-Qin Yang ◽  
...  

: Mitophagy plays an important role in maintaining mitochondrial quality and cell homeostasis through the degradation of damaged, aged, and dysfunctional mitochondria and misfolded proteins. Many human diseases, particularly neurodegenerative diseases, are related to disorders of mitochondrial phagocytosis. Exploring the regulatory mechanisms of mitophagy is of great significance for revealing the molecular mechanisms underlying the related diseases. Herein, we summarize the major mechanisms of mitophagy, the relationship of mitophagy with human diseases, and the role of traditional Chinese medicine (TCM) in mitophagy. These discussions enhance our knowledge of mitophagy and its potential therapeutic targets using TCM.


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