Plasmodium prevalence across avian host species is positively associated with exposure to mosquito vectors

Parasitology ◽  
2015 ◽  
Vol 142 (13) ◽  
pp. 1612-1620 ◽  
Author(s):  
MATTHEW C. I. MEDEIROS ◽  
ROBERT E. RICKLEFS ◽  
JEFFREY D. BRAWN ◽  
GABRIEL L. HAMER
Keyword(s):  
Host Species ◽  
Avian Malaria ◽  
Empirical Studies ◽  
Relative Number ◽  
Parasite Prevalence ◽  
Species Traits ◽  
Malaria Vectors ◽  
Future Research ◽  
Avian Host ◽  
Vector Borne

SUMMARYThe prevalence of vector-borne parasites varies greatly across host species, and this heterogeneity has been used to relate infectious disease susceptibility to host species traits. However, a few empirical studies have directly associated vector-borne parasite prevalence with exposure to vectors across hosts. Here, we use DNA sequencing of blood meals to estimate utilization of different avian host species by Culex mosquitoes, and relate utilization by these malaria vectors to avian Plasmodium prevalence. We found that avian host species that are highly utilized as hosts by avian malaria vectors are significantly more likely to have Plasmodium infections. However, the effect was not consistent among individual Plasmodium taxa. Exposure to vector bites may therefore influence the relative number of all avian Plasmodium infections among host species, while other processes, such as parasite competition and host-parasite coevolution, delimit the host distributions of individual Plasmodium species. We demonstrate that links between avian malaria susceptibility and host traits can be conditioned by patterns of exposure to vectors. Linking vector utilization rates to host traits may be a key area of future research to understand mechanisms that produce variation in the prevalence of vector-borne pathogens among host species.

scholarly journals Diversity, abundance, and host relationships in the avian malaria community of New Mexico pine forests

2017 ◽  
Author(s):  
Rosario A. Marroquin-Flores ◽  
Jessie L. Williamson ◽  
Andrea N. Chavez ◽  
Selina M. Bauernfeind ◽  
Matthew J. Baumann ◽  
...  
Keyword(s):  
New Mexico ◽  
Infection Rate ◽  
Ponderosa Pine ◽  
Host Species ◽  
Avian Malaria ◽  
Bird Community ◽  
Pine Forests ◽  
Avian Host ◽  
Breeding Bird ◽  
Ponderosa Pine Forests

Avian malaria parasites (genera Haemoproteus, Plasmodium, and Leucocytozoon) affect bird demography, distribution limits, and community structure, yet most bird communities and populations remain unsurveyed. We conducted a community-level survey of these vector-transmitted parasites in New Mexico, USA, to describe the diversity, abundance, and host associations. We focused on the breeding-bird community in the transition zone between piñon-juniper woodland and ponderosa pine forests (elevational range: 2150–2460 meters). We screened 186 birds representing 49 species using both standard PCR and microscopy techniques to detect infections of all three avian malaria genera. The combined infection rate was 36.6%, with the highest infection rate for Haemoproteus (20.9%), followed by Leucocytozoon (13.4%), then Plasmodium (8.0%). We sequenced mtDNA for 77 infections representing 43 haplotypes (25 Haemoproteus, 12 Leucocytozoon, 6 Plasmodium). When compared to all previously known lineages in the MalAvi and GenBank databases, 65% (28) of the haplotypes that we recovered were novel. We found evidence for host specificity at the avian clade and species level, but this specificity was variable among parasite genera. Haemoproteus and Leucocytozoon were each restricted to three avian host-clades or groups (out of six), while Plasmodium occurred in all groups except non-passerines. We found striking variation in infection rate among host species, with nearly universal infection among vireos and no infection among nuthatches. Using rarefaction and extrapolation, we estimated the total avian malaria diversity to be 70 haplotypes (95% CI: 43–98); thus, we may have already sampled ~60% of the diversity of avian malaria in New Mexico pine forests. It is possible that future studies will find higher diversity in microhabitats or host species that are under-sampled or unsampled in the present study. Fortunately, this study is fully extendable via voucher specimens, frozen tissues, blood smears, parasite images, and documentation provided in open-access databases (MalAvi, Genbank, and ARCTOS).

Yogic Intervention in Sexual Dysfunction - A Review

2017 ◽  
Vol 2 (4) ◽  
Author(s):  
Rakshith K. R. ◽  
Shivakumar . ◽  
Kaushal Sinha ◽  
Vijeth Kumar L. A.
Keyword(s):  
Psychological Functioning ◽  
Empirical Studies ◽  
Empirical Literature ◽  
Future Research ◽  
Therapeutic Effects ◽  
Yoga Therapy ◽  
Cognitive Component ◽  
Beneficial Effects ◽  
Breathing Exercises ◽  
The Mind

Yoga is an ancient practice with Eastern roots that involves both physical postures (Asanas) and breathing techniques (Pranayamas). Yoga therapy for male sexual problems can effectively be treated through Yoga therapy, particularly with the help of Yoga poses and breathing exercises, Yoga has proven itself highly very effective in the treatment of a number of incurable and sometimes terminable diseases. Then again, Yoga's therapeutic effects are just a spin-off and supplementary. Yoga which has proved to be very effective in the treatment of many impossible and incurable diseases, the therapeutic effect of Yoga is only a by product and incidental. Problems related to sex can very well be handled with Yoga as most often these problems are more related to the mind than body. Either they are caused by lack of confidence or stress or fatigue or fear and very few times some physical cause is there. There is also a cognitive component focusing on meditation and concentration, which aids in achieving the goal of union between the self and the spiritual. Although numerous empirical studies have found a beneficial effect of Yoga on different aspects of physical and psychological functioning, claims of Yoga's beneficial effects on sexuality derive from a rich but no empirical literature. The goal of this article is to review the philosophy and forms of Yoga, to review the no empirical and (limited) empirical literatures linking Yoga with enhanced sexuality, and to propose some future research avenues focusing on Yoga as a treatment for sexual disorder.

Emerging Syndromes

2017 ◽  
Author(s):  
Kelly C. Allison ◽  
Jennifer D. Lundgren
Keyword(s):  
Empirical Studies ◽  
Theoretical Models ◽  
Future Research ◽  
Night Eating Syndrome ◽  
Statistical Manual ◽  
Night Eating ◽  
Diagnostic And Statistical Manual ◽  
Impairment In Functioning ◽  
Atypical Anorexia Nervosa ◽  
Comorbid Psychopathology

The Diagnostic and Statistical Manual, fifth edition, of the American Psychiatric Association (2013) has designated several disorders under the diagnosis of otherwise specified feeding and eating disorder (OSFED). This chapter evaluates three of these, night eating syndrome (NES), purging disorder (PD), and atypical anorexia nervosa (atypical AN). It also reviews orthorexia nervosa, which has been discussed in the clinical realm as well as the popular press. The history and definition for each is reviewed, relevant theoretical models are presented and compared, and evidence for the usefulness of the models is described. Empirical studies examining the disorders’ independence from other disorders, comorbid psychopathology, and, when available, medical comorbidities, are discussed. Distress and impairment in functioning seem comparable between at least three of these emerging disorders and threshold eating disorders. Finally, remaining questions for future research are summarized.

Achieving Financial Inclusion for Persons With Disabilities: Exploring Preparedness and Accessibility of Financial Services for Persons With Disabilities in Malawi

2021 ◽  
pp. 104420732110275
Author(s):  
Alex Nester Jiya ◽  
Maxwell Peprah Opoku ◽  
William Nketsia ◽  
Joslin Alexei Dogbe ◽  
Josephine Nkrumah Adusei
Keyword(s):  
Financial Literacy ◽  
Financial Services ◽  
Commercial Banks ◽  
Empirical Studies ◽  
Well Being ◽  
Living Conditions ◽  
Inclusive Development ◽  
Future Research ◽  
Structured Interviews ◽  
Persons With Disabilities

Deplorable living conditions among persons with disabilities and the need to improve their living conditions cannot be overemphasized. This has triggered international discussion on the need for deliberate social policies to bridge the poverty gap between persons with and without disabilities. In Malawi, expansion of financial services has been identified as an essential tool to accelerate economic and inclusive development. However, empirical studies are yet to explore the preparedness of financial institutions to extend their services to persons with disabilities. In this qualitative study, semi-structured interviews were conducted with managers from commercial banks in Malawi to understand their perspectives on extending financial services to persons with disabilities. Interviews were transcribed verbatim and a descriptive thematic analysis was performed. Although participants reiterated the need to provide persons with disabilities with financial services to improve their well-being, few initiatives have been undertaken to improve their participation. Particularly, participants stated that barriers, such as a lack of financial literacy and adaptive technologies, communication barriers, and high rates of unemployment, explained the reluctance of commercial banks to extend financial services to persons with disabilities. The limitations, recommendations for future research, and implications of the study for policymaking have been highlighted.

A Scoping Review of Telehealth-Assisted Case Management for Chronic Illnesses

2021 ◽  
pp. 019394592110089
Author(s):  
Jee Young Joo ◽  
Megan F. Liu
Keyword(s):  
Health Care ◽  
Case Management ◽  
Scoping Review ◽  
Access To Health Care ◽  
Health Care Services ◽  
Care Delivery ◽  
Management Practice ◽  
Empirical Studies ◽  
Chronic Illnesses ◽  
Future Research

This scoping review aimed to examine telehealth-assisted case management for chronic illnesses and assess its overall impact on health care delivery. Guided by the PRISMA statement, this review included 36 empirical studies published between 2011 and 2020. This study identified three weaknesses and four strengths of telehealth-assisted case management. While the weaknesses were negative feelings about telehealth, challenges faced by patients in learning and using telehealth devices, and increased workload for case managers, the strengths included efficient and timely care, increased access to health care services, support for patients’ satisfaction, and cost savings. Future research can be designed and conducted for overcoming the weaknesses of telehealth-assisted case management. Additionally, the strengths identified by this review need to be translated from research into case management practice for chronic illness care. This review not only describes the value of such care strategy, but also provides implications for future nursing practice and research.

scholarly journals The Congregational Character Questionnaire: An Initial Empirical Examination of the Significance of Collective Church Character Traits

2021 ◽  
pp. 009164712110219
Author(s):  
T. Ryan Byerly ◽  
Keith J. Edwards ◽  
Peter C. Hill
Keyword(s):  
Meaning In Life ◽  
Satisfaction With Life ◽  
Empirical Studies ◽  
Well Being ◽  
Character Traits ◽  
Academic Disciplines ◽  
Future Research ◽  
Religious Congregations ◽  
Empirical Examination ◽  
Christian Churches

Researchers in several academic disciplines have begun to take an interest in group character traits, including the character traits of religious congregations. This article reports the first empirical studies of congregational virtues. The Congregational Character Questionnaire was developed for measuring 12 different virtues of Christian churches: clinging to apostolic teaching, honoring teachers, prayerfulness, hopefulness, discipleship, emotional supportiveness, material supportiveness, spiritual equality, unity, submission, peace with the world, and spreading the faith. The instrument was then used with an online sample ( N = 530) to study how congregants’ perceptions of their congregation’s virtuousness related to congregants’ evaluations of their congregation, participation in their congregation, as well as congregants’ satisfaction with life, presence of meaning in life, and religious well-being. Results indicated that congregants’ overall perceptions of congregational virtuousness were significantly positively related to all of these dependent variables. These results help to reveal the important role that congregational character may play in the experience of congregants. Directions for future research in this area are outlined.

scholarly journals Understanding mosquito host-choice behaviour: a new and low-cost method of identifying the sex of human hosts from mosquito blood meals

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Fiona Teltscher ◽  
Sophie Bouvaine ◽  
Gabriella Gibson ◽  
Paul Dyer ◽  
Jennifer Guest ◽  
...  
Keyword(s):  
Blood Meal ◽  
Host Species ◽  
Disease Transmission ◽  
Low Cost ◽  
Host Choice ◽  
Epidemiological Models ◽  
Choice Behaviour ◽  
Vector Borne ◽  
Transmission Models ◽  
Blood Meals

Abstract Background Mosquito-borne diseases are a global health problem, causing hundreds of thousands of deaths per year. Pathogens are transmitted by mosquitoes feeding on the blood of an infected host and then feeding on a new host. Monitoring mosquito host-choice behaviour can help in many aspects of vector-borne disease control. Currently, it is possible to determine the host species and an individual human host from the blood meal of a mosquito by using genotyping to match the blood profile of local inhabitants. Epidemiological models generally assume that mosquito biting behaviour is random; however, numerous studies have shown that certain characteristics, e.g. genetic makeup and skin microbiota, make some individuals more attractive to mosquitoes than others. Analysing blood meals and illuminating host-choice behaviour will help re-evaluate and optimise disease transmission models. Methods We describe a new blood meal assay that identifies the sex of the person that a mosquito has bitten. The amelogenin locus (AMEL), a sex marker located on both X and Y chromosomes, was amplified by polymerase chain reaction in DNA extracted from blood-fed Aedes aegypti and Anopheles coluzzii. Results AMEL could be successfully amplified up to 24 h after a blood meal in 100% of An. coluzzii and 96.6% of Ae. aegypti, revealing the sex of humans that were fed on by individual mosquitoes. Conclusions The method described here, developed using mosquitoes fed on volunteers, can be applied to field-caught mosquitoes to determine the host species and the biological sex of human hosts on which they have blood fed. Two important vector species were tested successfully in our laboratory experiments, demonstrating the potential of this technique to improve epidemiological models of vector-borne diseases. This viable and low-cost approach has the capacity to improve our understanding of vector-borne disease transmission, specifically gender differences in exposure and attractiveness to mosquitoes. The data gathered from field studies using our method can be used to shape new transmission models and aid in the implementation of more effective and targeted vector control strategies by enabling a better understanding of the drivers of vector-host interactions.

scholarly journals Molecular Identification of New Cases of Human Dirofilariosis (Dirofilaria repens) in Italy

Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 251
Author(s):  
Simona Gabrielli ◽  
Valentina Mangano ◽  
Federica Furzi ◽  
Alessandra Oliva ◽  
Serena Vita ◽  
...  
Keyword(s):  
Molecular Diagnosis ◽  
Central Italy ◽  
Research Work ◽  
Pulmonary Nodules ◽  
Elisa Test ◽  
Future Research ◽  
Worldwide Distribution ◽  
Human Dirofilariosis ◽  
Vector Borne ◽  
Etiological Agents

(1) Dirofilariosis is a vector-borne parasitic disease mainly in domestic and wild carnivores caused by Dirofilaria (Noctiella) repens, which is endemic in many countries of the Old World, and D. immitis, which has a worldwide distribution. In recent years, an increase in the number of human cases has been reported, suggesting that dirofilariosis is an emergent zoonosis. Here, we describe further cases (N = 8), observed in Central Italy during the years 2018–2019. (2) Molecular diagnosis was performed on: (i) live worms extracted from ocular conjunctiva, cheek, and calf muscle; (ii) histological sections of surgically removed nodules from parenchymal lung, coccyx, and breast. (3) Sequence analysis (650-bp) of the mitochondrial cytochrome oxidase subunit I gene (mtDNA cox1) showed a match of 100% with the sequences of D. repens previously deposited in GenBank. ELISA test to detect IgG against filarial antigens was performed on four patients’ sera and resulted positive in two patients who showed ocular and subcutaneous dirofilariosis, respectively. Microfilariae have been never detected in the peripheral blood of the patients. (4) The occurrence of N = 8 new cases of human D. repens-infections observed in a two-year period suggests an increased circulation of the parasite in Italy. Therefore, dirofilariosis should be included in differential diagnosis in patients presenting subcutaneous and/or pulmonary nodules. Molecular diagnosis of the etiological agents is fundamental. Specific serological diagnosis needs to be improved in future research work.

scholarly journals Perception of Gamblers: A Systematic Review

2021 ◽  
Author(s):  
Andrea Wöhr ◽  
Marius Wuketich
Keyword(s):  
Systematic Review ◽  
Empirical Studies ◽  
Grey Literature ◽  
Future Research ◽  
Gambling Problems ◽  
Negative Effects ◽  
Strong Focus ◽  
The Media ◽  
Social Scientific ◽  
Psychological Knowledge

AbstractIt is generally assumed that gamblers, and particularly people with gambling problems (PG), are affected by negative perception and stigmatisation. However, a systematic review of empirical studies investigating the perception of gamblers has not yet been carried out. This article therefore summarises empirical evidence on the perception of gamblers and provides directions for future research. A systematic literature review based on the relevant guidelines was carried out searching three databases. The databases Scopus, PubMed and BASE were used to cover social scientific knowledge, medical-psychological knowledge and grey literature. A total of 48 studies from 37 literature references was found. The perspective in these studies varies: Several studies focus on the perception of gamblers by the general population, by subpopulations (e. g. students or social workers), or by gamblers on themselves. The perspective on recreational gamblers is hardly an issue. A strong focus on persons with gambling problems is symptomatic of the gambling discourse. The analysis of the studies shows that gambling problems are thought to be rather concealable, whereas the negative effects on the concerned persons‘ lives are rated to be quite substantial. PG are described as “irresponsible” and “greedy” while they perceive themselves as “stupid” or “weak”. Only few examples of open discrimination are mentioned. Several studies however put emphasis on the stereotypical way in which PG are portrayed in the media, thus contributing to stigmatisation. Knowledge gaps include insights from longitudinal studies, the influence of respondents‘ age, culture and sex on their views, the relevance of the type of gambling a person is addicted to, and others. Further studies in these fields are needed.

scholarly journals Personality trait differences across types of entrepreneurs: a systematic literature review

2021 ◽  
Author(s):  
Florentine U. Salmony ◽  
Dominik K. Kanbach
Keyword(s):  
Literature Review ◽  
Personality Traits ◽  
Systematic Literature Review ◽  
Empirical Studies ◽  
Academic Research ◽  
Future Research ◽  
Rural Farmers ◽  
Start Up ◽  
Wide Range ◽  
Research Integration

AbstractThe personality traits that define entrepreneurs have been of significant interest to academic research for several decades. However, previous studies have used vastly different definitions of the term “entrepreneur”, meaning their subjects have ranged from rural farmers to tech-industry start-up founders. Consequently, most research has investigated disparate sub-types of entrepreneurs, which may not allow for inferences to be made regarding the general entrepreneurial population. Despite this, studies have frequently extrapolated results from narrow sub-types to entrepreneurs in general. This variation in entrepreneur samples reduces the comparability of empirical studies and calls into question the reviews that pool results without systematic differentiation between sub-types. The present study offers a novel account by differentiating between the definitions of “entrepreneur” used in studies on entrepreneurs’ personality traits. We conduct a systematic literature review across 95 studies from 1985 to 2020. We uncover three main themes across the previous studies. First, previous research applied a wide range of definitions of the term “entrepreneur”. Second, we identify several inconsistent findings across studies, which may at least partially be due to the use of heterogeneous entrepreneur samples. Third, the few studies that distinguished between various types of entrepreneurs revealed differences between them. Our systematic differentiation between entrepreneur sub-types and our research integration offer a novel perspective that has, to date, been widely neglected in academic research. Future research should use clearly defined entrepreneurial samples and conduct more systematic investigations into the differences between entrepreneur sub-types.

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