scholarly journals Susceptibility of anurans, lizards, and fish to infection with Dracunculus species larvae and implications for their roles as paratenic hosts

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Erin K. Box ◽  
Michael J. Yabsley ◽  
Kayla B. Garrett ◽  
Alec T. Thompson ◽  
Seth T. Wyckoff ◽  
...  
Keyword(s):  
Post Infection ◽  
Novel Species ◽  
Life Cycles ◽  
Future Research ◽  
Parasitic Nematodes ◽  
Lizard Species ◽  
Third Stage ◽  
Paratenic Hosts

AbstractDracunculus spp. are parasitic nematodes that infect numerous species of mammals and reptiles. The life cycles of Dracunculus species are complex, and unknowns remain regarding the role of paratenic and transport hosts in transmission to definitive hosts. We had two primary objectives: to assess the susceptibility of several species of anurans, lizards, and fish as paratenic hosts for Dracunculus species, and to determine the long-term persistence of Dracunculus infections in African clawed frogs (Xenopus laevis). Animals were orally exposed to copepods infected with infectious third-stage larvae (L3s) of either Dracunculus insignis or D. medinensis. Dracunculus L3s were recovered from four anuran species, two lizard species, and one fish species, demonstrating that Dracunculus can infect tissues of a diversity of species. In long-term persistence trials, D. medinensis L3s were recovered from African clawed frogs tissues up to 58 days post-infection, and D. insignis L3s were recovered up to 244 days post-infection. Our findings regarding the susceptibility of novel species of frogs, lizards, and fish to infection with Dracunculus nematodes, and long-term persistence of L3s in paratenic hosts, address pressing knowledge gaps regarding Dracunculus infection in paratenic hosts and may guide future research regarding the transmission of Dracunculus to definitive mammalian hosts.

scholarly journals Effect of Barley Sowing Density on the Integrated Weed Management of Lolium rigidum (Annual Ryegrass) in Mediterranean Dryland: A Modeling Approach

Agronomy ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1565
Author(s):  
María Belén D’Amico ◽  
Guillermo R. Chantre ◽  
Guillermo L. Calandrini ◽  
José L. González-Andújar
Keyword(s):  
Weed Management ◽  
Life Cycles ◽  
Integrated Weed Management ◽  
Future Research ◽  
Seed Removal ◽  
Weed Infestation ◽  
High Control ◽  
Weed Dynamics ◽  
The Impact

Population models are particularly helpful for understanding long-term changes in the weed dynamics associated with integrated weed management (IWM) strategies. IWM practices for controlling L. rigidum are of high importance, mainly due to its widespread resistance that precludes chemical control as a single management method. The objective of this contribution is to simulate different IWM scenarios with special emphasis on the impact of different levels of barley sowing densities on L. rigidum control. To this effect, a weed–crop population model for both L. rigidum and barley life cycles was developed. Our results point out: (i) the necessity of achieving high control efficiencies (>99%), (ii) that the increase of twice the standard sowing density of barley resulted in a reduction of 23.7% of the weed density, (iii) non-herbicide-based individual methods, such as delayed sowing and weed seed removal at harvest, proved to be inefficient for reducing drastically weed population, (iv) the implementation of at least three control tactics (seed removal, delay sowing and herbicides) is required for weed infestation eradication independently of the sowing rate, and (v) the effect of an increase in the sowing density is diluted as a more demanding weed control is reached. Future research should aim to disentangle the effect of different weed resistance levels on L. rigidum population dynamics and the required efficiencies for more sustainable IWM programs.

scholarly journals The Long-term Effects of Instruction on EFL Learners' Use of Complaining Formulas

10.29007/5xsb ◽  
2018 ◽  
Author(s):  
Alicia Martínez-Flor ◽  
Esther Usó-Juan
Keyword(s):  
Foreign Language ◽  
Language Learners ◽  
Future Research ◽  
Long Term Effects ◽  
Positive Role ◽  
Efl Learners ◽  
Foreign Language Learners ◽  
Over Time

Studies analysing the positive role of pragmatic instruction in formal settings have increased over the last decades. Within this area of interventional pragmatics, some studies have particularly examined whether the effectiveness of the instruction implemented is sustained over time. In order to shed more light on the long-term effects of instruction, this research investigates English as a Foreign Language learners’ use of complaining formulas not only after immediately receiving instruction, but also two months later. Results show that learners keep using a variety of appropriate complaining formulas two months after having participated in the instructional period. These findings are discussed and directions for future research suggested.

scholarly journals The Role of Interferons in Driving Susceptibility to Asthma Following Bronchiolitis: Controversies and Research Gaps

2021 ◽  
Vol 12 ◽  
Author(s):  
Heidi Makrinioti ◽  
Andrew Bush ◽  
James Gern ◽  
Sebastian Lennox Johnston ◽  
Nikolaos Papadopoulos ◽  
...  
Keyword(s):  
Immune Responses ◽  
Acute Infection ◽  
Respiratory Viruses ◽  
Future Research ◽  
Innate Immune Responses ◽  
Asthmatic Children ◽  
Recurrent Wheeze ◽  
The Relationship

Bronchiolitis is the most common cause of hospitalization in infancy and is associated with a higher risk for the development of childhood asthma. However, not all children hospitalized with bronchiolitis will develop asthma. The mechanisms underlying asthma development following bronchiolitis hospitalization are complex. Immune responses to respiratory viruses may underlie both bronchiolitis severity and long-term sequela (such as asthma). Interferons (IFNs) are important components of innate immune responses to respiratory viruses and could influence both asthma development and asthma exacerbations. However, the nature of the relationship between interferon production and wheezing illnesses is controversial. For example, low peripheral blood IFN responses at birth have been linked with recurrent wheeze and asthma development. In contrast, there is evidence that severe illnesses (e.g., hospitalization for bronchiolitis) are associated with increased IFN responses during acute infection (bronchiolitis hospitalization) and a higher risk for subsequent asthma diagnosis. Furthermore, mechanistic studies suggest that bronchial epithelial cells from asthmatic children have impaired IFN responses to respiratory viruses, which may enable increased viral replication followed by exaggerated secondary IFN responses. This review aims to discuss controversies around the role of IFNs as drivers of susceptibility to asthma development following bronchiolitis hospitalization. Past evidence from both mechanistic and cohort studies are discussed. We will highlight knowledge gaps that can inform future research study design.

Does deal size moderate the effects of board faultlines? Evidence from acquisitions

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Daniel Tidbury ◽  
Steven F. Cahan ◽  
Li Chen
Keyword(s):  
Fixed Effects ◽  
Quantitative Research ◽  
Future Research ◽  
Research Approach ◽  
Strategic Decisions ◽  
Negative Effects ◽  
Content Type ◽  
Instrumental Variable Analysis

Purpose Board faultlines, which reflect intrinsic divisions of board members into relatively homogeneous subgroups, are associated with poor firm performance. This paper aims to extend the existing board faultline research by examining how acquisition deal size moderates the negative implications of board faultlines. Design/methodology/approach This paper uses a sample of acquisitions and a quantitative research approach to conduct statistical analysis. Findings Using a sample of acquisitions announced between 2007 and 2016, this paper finds evidence suggesting that strong faultlines are associated with poorer acquisition outcomes in the long-term, but not in the short term. Further, this paper finds that the effect of faultline strength on long-term acquisition outcomes is weaker for larger acquisition deals than smaller acquisition deals. The findings are consistent with deal size moderating the relation between faultlines and acquisition outcomes. Research limitations/implications This paper addresses possible endogeneity through firm fixed effects and instrumental variable analysis. Although this paper provides evidence on the moderating role of deal size in the context of faultlines, future research could examine the role of additional moderators, such as pro-diversity, trust, board leadership and board and task characteristics. Practical implications The findings suggest that boards need to be aware of situations where the negative effects of faultlines are more likely to come to the fore. For example, faultlines are more likely to play a role in more routine, obscure monitoring than for high-profile strategic decisions. Originality/value The study is multidisciplinary as it draws on the management, organizational behaviour and psychology and finance literature. It contributes to the developing literature on faultlines in several important ways. First, this paper supports their view that faultlines have adverse effects on board performance by showing that faultlines negatively impact discrete strategic investment decisions. Second, this paper provides evidence that deals size moderates the faultline-acquisition performance relation, indicating that the role of faultlines is contextual. Third, this paper finds evidence that suggests investors do not factor in board faultlines when responding to acquisition announcements.

Physiological and morphological effects of climate change

2019 ◽  
pp. 120-133 ◽  
Author(s):  
Andrew E. McKechnie
Keyword(s):  
Climate Change ◽  
Body Mass ◽  
High Temperatures ◽  
Arid Zone ◽  
Future Research ◽  
Long Term Effects ◽  
Adaptation To Climate Change ◽  
Heat Events

The direct impacts of higher temperatures on birds are manifested over timescales ranging from minutes and hours to years and decades. Over short timescales, acute exposure to high temperatures can lead to hyperthermia or dehydration, which among arid-zone species occasionally causes catastrophic mortality events. Over intermediate timescales of days to weeks, high temperatures can have chronic sub-lethal effects via body mass loss or reduced nestling growth rates, negatively affecting sev eral fitness components. Long-term effects of warming manifested over years to decades involve declining body mass or changes in appendage size. Key directions for future research include elucidating the role of phenotypic plasticity and epigenetic processes in avian adaptation to climate change, examining the role of stress pathways in mediating responses to heat events, and understanding the consequences of higher temperatures for species that traverse hot regions while migrating.

scholarly journals Psychedelics and potential benefits in “healthy normals”: A review of the literature

2019 ◽  
Vol 3 (3) ◽  
pp. 280-287 ◽  
Author(s):  
Sam Gandy
Keyword(s):  
Psychological Functioning ◽  
Well Being ◽  
Future Research ◽  
Life Meaning ◽  
Potential Development ◽  
Potential Benefits ◽  
High Doses ◽  
And Behavior

We are in the midst of a psychedelic research renaissance. With research examining the efficacy of psychedelics as a treatment for a range of mental health indications still in its early stages, there is an increasing body of research to show that careful use of psychedelics can yield a variety of benefits in “healthy normals” and so lead to “the betterment of well people.” Psychedelics have been found to modulate neuroplasticity, and usage in a supportive setting can result in enduring increases in traits such as well-being, life satisfaction, life meaning, mindfulness, and a variety of measures associated with prosocial behaviors and healthy psychological functioning. The effect of psychedelic experience on measures of personality trait openness and is potential implications is examined, and the potential role of awe as a mediator of the benefits of the psychedelic experience is discussed. Special attention is given to the capacity of psychedelics to increase measures of nature relatedness in an enduring sense, which is being correlated with a broad range of measures of psychological well-being as well as a key predictor of pro-environmental awareness and behavior. The effects of particular classical psychedelic compounds on healthy people are discussed, with special attention given to the mystical-type experiences occasioned by high doses of psychedelics, which appear to be an important mediator of long-term benefits and psychotherapeutic gains. Research looking at the potential benefits of psychedelic microdosing is discussed. Potential future research avenues are explored, focusing on the potential development of psychedelics as agents of ecotherapy.

scholarly journals Endocrine treatment of transsexual persons: an Endocrine Society Clinical Practice Guideline: commentary from a European perspective

2010 ◽  
Vol 162 (5) ◽  
pp. 831-833 ◽  
Author(s):  
M C Meriggiola ◽  
E A Jannini ◽  
A Lenzi ◽  
M Maggi ◽  
C Manieri
Keyword(s):  
Hormonal Treatment ◽  
Diagnostic Procedures ◽  
Endocrine Treatment ◽  
Future Research ◽  
Sex Reassignment Surgery ◽  
Term Care ◽  
Endocrine Society ◽  
Diagnostic Role

The treatment of transsexual subjects is a challenging task for the endocrinologist who, in collaboration with the mental health professional and the surgeon, is called upon to confirm the diagnosis and adjust hormonal treatment aimed at suppressing endogenous sex hormones and to develop hormone characteristics of the desired gender. These guidelines are structured to provide evidence-based suggestions or, where evidence is lacking, expert recommendations on diagnostic procedures and hormonal treatment in adolescent and adult transsexuals, including long-term care and eligibility for surgery. The multidisciplinary approach to treatment, the additional diagnostic role of hormone administration and the need to maintain hormone levels within the physiological range are key suggestions stressed in the guidelines which are particularly important for an endocrinologist unfamiliar with this field. The need for psychological assessment before surgery is not common in many countries and should be stressed further in the guidelines. Some important issues such as time and method of hormone withdrawal before surgery together with when and which hormones should be administered after sex reassignment surgery has been completed also remain unclear.These guidelines represent a pivotal document for endocrinologists setting a standard for the care of transsexuals and providing directions for future research.

scholarly journals Malnutrition in healthcare settings and the role of gastrostomy feeding

2016 ◽  
Vol 76 (3) ◽  
pp. 352-360 ◽  
Author(s):  
Matthew Kurien ◽  
Jake Williams ◽  
David S. Sanders
Keyword(s):  
Nutritional Support ◽  
Feeding Tube ◽  
Morbidity And Mortality ◽  
Future Research ◽  
Economic Costs ◽  
Psychological Function ◽  
Feeding Tubes ◽  
Healthcare Settings

Malnutrition can adversely affect physical and psychological function, influencing both morbidity and mortality. Despite the prevalence of malnutrition and its associated health and economic costs, malnutrition remains under-detected and under-treated in differing healthcare settings. For a subgroup of malnourished individuals, a gastrostomy (a feeding tube placed directly into the stomach) may be required to provide long-term nutritional support. In this review we explore the spectrum and consequences of malnutrition in differing healthcare settings. We then specifically review gastrostomies as a method of providing nutritional support. The review highlights the origins of gastrostomies, and discusses how endoscopic and radiological advances have culminated in an increased demand and placement of gastrostomy feeding tubes. Several studies have raised concerns about the benefits derived following this intervention and also about the patients selected to undergo this procedure. These studies are discussed in detail in this review, alongside suggestions for future research to help better delineate those who will benefit most from this intervention, and improve understanding about how gastrostomies influence nutritional outcomes.

scholarly journals Theoretical Approaches to Nuclear Proliferation

2015 ◽  
pp. 130-138
Author(s):  
K. S. Tarasov
Keyword(s):  
Nuclear Weapons ◽  
Nuclear Proliferation ◽  
Future Research ◽  
Security Environment ◽  
Future Research Agenda ◽  
Theoretical Approaches ◽  
Short And Long Term ◽  
Major Factors

This article analyses discussions between representatives of three schools in the theory of international relations - realism, liberalism and constructivism - on the driving factors of nuclear proliferation. The paper examines major theoretical approaches, outlined in the studies of Russian and foreign scientists, to the causes of nuclear weapons development, while unveiling their advantages and limitations. Much of the article has been devoted to alternative approaches, particularly, the role of mathematical modeling in assessing proliferation risks. The analysis also reveals a variety of different approaches to nuclear weapons acquisition, as well as the absence of a comprehensive proliferation theory. Based on the research results the study uncovers major factors both favoring and impeding nuclear proliferation. The author shows that the lack of consensus between realists, liberals and constructivists on the nature of proliferation led a number of scientists to an attempt to explain nuclear rationale by drawing from the insights of more than one school in the theory of IR. Detailed study of the proliferation puzzle contributes to a greater understating of contemporary international realities, helps to identify mechanisms that are most likely to deter states from obtaining nuclear weapons and is of the outmost importance in predicting short- and long-term security environment. Furthermore, analysis of the existing scientific literature on nuclear proliferation helps to determine future research agenda of the subject at hand.

scholarly journals Role of Business Age, Scale & Risk in Debt Financing Choices for the Pakistani Textile & Apparel Industry

e-Finanse ◽  
2020 ◽  
Vol 16 (3) ◽  
pp. 119-136
Author(s):  
Zahid Bashir ◽  
Muhammad Usman Arshad ◽  
Muhammad Asif ◽  
Muhammad Abbas ◽  
Hasnain Ali
Keyword(s):  
Debt Financing ◽  
Future Research ◽  
Debt Ratio ◽  
Equity Financing ◽  
Tax Shield ◽  
Total Debt ◽  
Textile And Apparel ◽  
Financing Choice

Abstract The motivation for this research enquiry is to identify the role of the business age, size and risk for the choice of debt financing in the textile and apparel sector of Pakistan along with other controlled factors. The textile and apparel sector of Pakistan comprises 464 listed entities as the targeted population while the study randomly finalized 60 firms as the sample after carefully analyzing the required information from the financial statements during the annual revenue streams of 2013-2019. The predicted variable for this research enquiry is measured by short, long and total-debt ratios while the predictor variables include the business age, firm’s scale and risk. In addition, the research includes tax shield, tangibility, liquidity, profitability, and growth as the controlling factors. The study estimated that the choice of total-debt ratio is strongly affected by business age, size and risk along-with tax shield, tangibility, liquidity and profitability while the choice of short-term debt ratio mainly depends upon the firm’s scale and age along with the tax shield. In addition, the choice of long-term debt ratio is strongly explained by the firm’s scale and age along with the tax shield, liquidity and profitability. The estimated evidence provides management with the implications for the textile and apparel sector of Pakistan to consider as significant factors in deciding the debt financing choice of this sector. The estimated evidence of this research enquiry applies to the non-financial textile sector only and cannot be generalized to the financial sector. Future research may enhance the financing choice towards the inclusion of equity financing with the same set of variables.

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