scholarly journals Limited evidence of a genetic basis for sex determination in the common creek chub, Semotilus atromaculatus

2021 ◽  
Author(s):  
Amanda V. Meuser ◽  
Cassandre B. Pyne ◽  
Elizabeth G. Mandeville
Keyword(s):  
Sex Determination ◽  
Genetic Basis ◽  
Genotyping By Sequencing ◽  
Semotilus Atromaculatus ◽  
Evolutionary Diversification ◽  
Wide Range ◽  
The Common ◽  
Creek Chub ◽  
Determination Mechanism ◽  
Insight Into

1AbstractSexual reproduction is almost universal in the animal kingdom; therefore, each species must have a mechanism for designating sex as male or female. Fish especially have a wide range of sex determining systems. While incompatible systems are thought to increase reproductive isolation, interspecific hybridization is common among groups such as cyprinid minnows, thus, studies such as this can provide insight into hybridization and evolutionary diversification of this clade. In the present study, we aimed to identify a genetic basis for sex determination in the common creek chub (Semotilus atromaculatus) using genotyping-by-sequencing (GBS) data. No sex-associated markers were found by RADSex or a GWAS using GEMMA, however, our Weir and Cockerham locus-specific FST analysis and discriminant analysis of principal components revealed some genetic differentiation between the sexes at several loci. While no explicit sex determination mechanism has been yet discovered in creek chub, these loci are potential candidates for future studies. This study also highlights technical challenges involved in studying sex determination in species with extremely variable mechanisms.

Some little-known and new protozoan parasites of fish from Lake Sasajewun, Algonquin Park, Ontario

1989 ◽  
Vol 67 (6) ◽  
pp. 1372-1379 ◽  
Author(s):  
Jiří Lom ◽  
Sherwin S. Desser ◽  
Iva Dyková
Keyword(s):  
Tissue Specificity ◽  
Polar Filament ◽  
Lepomis Gibbosus ◽  
Renal Tubules ◽  
Protozoan Parasites ◽  
Sporocyst Residuum ◽  
Semotilus Atromaculatus ◽  
Ictalurus Nebulosus ◽  
The Common ◽  
Creek Chub

One hundred and twenty-six fish of eight species, taken from Lake Sasajewun, Ontario, were examined for protozoan parasites. Detailed descriptions are given for Sphaerospora diminuta Li and Desser from the pumpkinseed, Lepomis gibbosus, and for Goussia degiustii Molnar and Fernando from the common shiner, Notropis cornutus. Oocysts of G. degiustii are pleomorphic and exhibit low tissue specificity. Goussia freemani Molnar and Fernando from the kidney of N. cornutus is tentatively synonymized with Goussia leucisci Shulman and Zaika. Two new species of Sphaerospora are described: Sphaerospora paulini n.sp. from the renal tubules of creek chub, Semotilus atromaculatus, with spherical spores 8.1 (8.0–8.5) μm in diameter, containing ovoid polar capsules 2.8 (2.5–3.4) × 2.6 (2.5–3.0) μm, and polar filament with 4–5 coils; and Sphaerospora hankai n.sp. from the renal tubules of the brown bullhead, Ictalurus nebulosus, with subspherical spores 6.1 (5.4–6.6) × 6.0 (5.4–6.5) μm, unequal subspherical polar capsules (larger, 2.8 (2.5–3.1) × 2.7 (2.3–2.9) μm; smaller, 2.4 (2.1–2.6) × 2.0 (1.9–2.2) μm), and polar filament with 4–5 coils in larger capsule, 3–4 coils in smaller capsule. Eimeria patersoni n.sp. is described from the kidney, spleen, and liver of L. gibbosus. Oocysts are subspherical (11.9 × 10.6), sporocysts ellipsoidal (10.4 (9.9–11.2) × 3.5 (2.6–4.0) μm), and sporozoites stubby (3.6 × 2.0 μm); sporocyst residuum has 1–3 large granules.

11. Surveys

2020 ◽  
pp. 284-308
Author(s):  
Sandra Halperin ◽  
Oliver Heath
Keyword(s):  
Measurement Error ◽  
Survey Research ◽  
Random Sampling ◽  
Sampling Error ◽  
Questionnaire Design ◽  
Wide Range ◽  
Asking Questions ◽  
The Common ◽  
Interviewing Techniques ◽  
Insight Into

This chapter discusses the principles of survey research as well as the issues and problems associated with different stages of the research design process. In particular, it examines questionnaire design, sample design, and interviewing techniques, along with the common sources of error that affect survey research and what can be done to try and avoid or minimize them. Although surveys have several weaknesses, they are widely used in political research to investigate a wide range of political phenomena. They combine two things: obtaining information from people by asking questions and random sampling. When done well, surveys provide an accurate and reliable insight into what ordinary people think about politics and how they participate in politics. The chapter considers the elements of a survey that need to be addressed, namely: questionnaire design, measurement error, sampling design, sampling error, and interview mode.

scholarly journals Mapping the sex determination region in the Salix F1 hybrid common parent population confirms a ZW system in six diverse species

2021 ◽  
Author(s):  
Dustin G Wilkerson ◽  
Bircan Taskiran ◽  
Craig H Carlson ◽  
Lawrence B Smart
Keyword(s):  
Population Structure ◽  
Sex Determination ◽  
Complex Traits ◽  
Genotyping By Sequencing ◽  
Chromosome 15 ◽  
Bioenergy Crop ◽  
Parent Population ◽  
F1 Hybrid ◽  
Wide Range ◽  
Common Parent

Within the genus Salix, there are approximately 350 species native primarily to the northern hemisphere and adapted to a wide range of habitats. This diversity can be exploited to mine novel alleles conferring variation important for production as a bioenergy crop, but also to identify evolutionarily important genes, such as those involved in sex determination. To leverage this diversity, we created a mapping population by crossing six Salix species (S. viminalis, S. suchowensis, S. integra, S. koriyanagi, S. udensis, and S. alberti) to common male and female S. purpurea parents. Each family was genotyped via genotyping-by-sequencing and assessed for kinship and population structure as well as the construction of 16 backcross linkage maps to be used as a genetic resource for breeding and selection. Analyses of population structure resolved both the parents and F1 progeny to their respective phylogenetic section and indicated that the S. alberti parent was misidentified and was most likely S. suchowensis. Sex determining regions were identified on Salix chromosome 15 in the female-informative maps for seven of the eight families indicating that these species share a common female heterogametic ZW sex system. The eighth family, S. integra S. purpurea, was entirely female and had a truncated chromosome 15. Beyond sex determination, the Salix F1 hybrid common parent population (Salix F1HCP) introduced here will be useful in characterizing genetic factors underlying complex traits, aid in marker-assisted selection, and support genome assemblies for this promising bioenergy crop.

scholarly journals The Snakeskin Gourami (Trichopodus pectoralis) Tends to Exhibit XX/XY Sex Determination

Fishes ◽  
2021 ◽  
Vol 6 (4) ◽  
pp. 43
Author(s):  
Thitipong Panthum ◽  
Nararat Laopichienpong ◽  
Ekaphan Kraichak ◽  
Worapong Singchat ◽  
Dung Ho My Nguyen ◽  
...  
Keyword(s):  
Sex Differences ◽  
Sex Determination ◽  
Y Chromosome ◽  
Cytogenetic Analysis ◽  
Genotyping By Sequencing ◽  
Sexually Dimorphic ◽  
Determination System ◽  
Sex Determination System ◽  
Male Specific ◽  
Determination Mechanism

The snakeskin gourami (Trichopodus pectoralis) has a high meat yield and is one of the top five aquaculture freshwater fishes in Thailand. The species is not externally sexually dimorphic, and its sex determination system is unknown. Understanding the sex determination system of this species will contribute to its full-scale commercialization. In this study, a cytogenetic analysis did not reveal any between-sex differences in chromosomal patterns. However, we used genotyping-by-sequencing to identify 4 male-linked loci and 1 female-linked locus, indicating that the snakeskin gourami tends to exhibit an XX/XY sex determination system. However, we did not find any male-specific loci after filtering the loci for a ratio of 100:0 ratio of males:females. This suggests that the putative Y chromosome is young and that the sex determination region is cryptic. This approach provides solid information that can help identify the sex determination mechanism and potential sex determination regions in the snakeskin gourami, allowing further investigation of genetic improvements in the species.

scholarly journals Promotion of exercise in the management of cystic fibrosis - summary of national meetings

2018 ◽  
Vol 6 (2) ◽  
pp. 196 ◽  
Author(s):  
Owen William Tomlinson ◽  
James Shelley ◽  
Sarah Denford ◽  
Alan R Barker ◽  
Patrick J Oades ◽  
...  
Keyword(s):  
Physical Activity ◽  
Cystic Fibrosis ◽  
Roles And Responsibilities ◽  
Health And Wellbeing ◽  
Wide Range ◽  
The Common ◽  
Insight Into ◽  
Multi Disciplinary Team ◽  
Current Provision

Rationale, aims and objectives: Physical activity (PA) and exercise are important in maintaining and improving health and wellbeing in people with cystic fibrosis (CF) and measures of exercise capacity are useful outcomes in monitoring disease progression. The roles and responsibilities of CF multi-disciplinary team (MDT) members in supporting PA and exercise have yet to be fully defined. This communication reports on national meetings of CF MDT staff whose interest is to improve and standardise person-centered exercise provision and testing as part of routine CF care. We also introduce the role of the physiotherapy technician in supporting PA interventions.Meetings: The two meetings covered a range of presentations, discussions and workshops, focusing on the role of exercise and PA in CF management. Forty people from 15 NHS Hospital Trusts and 3 universities were asked to provide feedback via a questionnaire.Results: The common roles and responsibilities of clinical staff involved in exercise testing and prescription are described, with a wide range of duties identified. In addition, physiotherapists were reported as the main MDT member responsible for exercise provision. The majority of teams reported discussing exercise at every clinical visit (57%) and felt confident in discussing exercise with patients (67%).Conclusions: While this report highlights the current provision of exercise in CF MDTs, it also provides insight into the resources MDTs may require in order to enhance the profile of exercise within CF services, including enhanced training, guidelines and standardised clinical roles.

11. Surveys

2017 ◽  
Author(s):  
Sandra Halperin ◽  
Oliver Heath
Keyword(s):  
Survey Research ◽  
Sampling Design ◽  
Sampling Error ◽  
Questionnaire Design ◽  
Ordinary People ◽  
Wide Range ◽  
Asking Questions ◽  
The Common ◽  
Interviewing Techniques ◽  
Insight Into

This chapter discusses the principles of survey research as well as the issues and problems associated with different stages of the research design process. In particular, it examines questionnaire design, sample design, and interviewing techniques, along with the common sources of error that affect survey research and what can be done to try and avoid or minimize them. Although surveys have several weaknesses, they are widely used in political research to investigate a wide range of political phenomena. They combine two things: obtaining information from people by asking questions and random sampling. When done well, surveys provide an accurate and reliable insight into what ordinary people think about politics and how they participate in politics. The chapter considers the elements of a survey that need to be addressed, namely: questionnaire design, measurement error, sampling design, sampling error, and interview mode.

Trichodina algonquinensis, a new species of peritrich ciliate from Ontario freshwater fish, and observations on its transmission

1983 ◽  
Vol 61 (5) ◽  
pp. 1159-1164 ◽  
Author(s):  
Lianxiang Li ◽  
Sherwin S. Desser
Keyword(s):  
Perca Flavescens ◽  
Lateral View ◽  
The Body ◽  
Semotilus Atromaculatus ◽  
Mean Diameter ◽  
The Common ◽  
The Mean ◽  
Golden Shiners ◽  
Creek Chub ◽  
A New Species

Trichodina algonquinensis n. sp. is described from the urinary bladder and ureters of the perch (Perca flavescens) and the common shiner (Notropis cornutus) from Lake Sasajewun, Algonquin Park, Ontario. The ciliate is hat shaped, flattened, and ellipsoidal in lateral view. The mean diameter of the oral portion of the body is 88.4 μm (58.5–123.5 μm; n = 21) and of the adhesive disc, 54.9 μm (42.9–57.2 μm; n = 30). It has 38 (35–42; n = 17) denticles, a horseshoe-shaped macronucleus, a round to ovoid micronucleus situated near the end of one arm of the macronucleus, and the oral groove spiral is 540°. Experiments indicate that in aquaria the ciliate is readily transmitted from perch to common shiners and golden shiners (Notemigonus crysoleucas) but not to creek chub (Semotilus atromaculatus).

Sentence-Based Experience Logging in New Hearing Aid Users

2020 ◽  
Vol 29 (3S) ◽  
pp. 631-637
Author(s):  
Katja Lund ◽  
Rodrigo Ordoñez ◽  
Jens Bo Nielsen ◽  
Dorte Hammershøi
Keyword(s):  
Hearing Aid ◽  
Patient Experiences ◽  
Online Tool ◽  
Rehabilitation Process ◽  
Hearing Rehabilitation ◽  
Clinical Observations ◽  
Hearing Aid Use ◽  
Wide Range ◽  
Insight Into ◽  
Shed Light

Purpose The aim of this study was to develop a tool to gain insight into the daily experiences of new hearing aid users and to shed light on aspects of aided performance that may not be unveiled through standard questionnaires. Method The tool is developed based on clinical observations, patient experiences, expert involvement, and existing validated hearing rehabilitation questionnaires. Results An online tool for collecting data related to hearing aid use was developed. The tool is based on 453 prefabricated sentences representing experiences within 13 categories related to hearing aid use. Conclusions The tool has the potential to reflect a wide range of individual experiences with hearing aid use, including auditory and nonauditory aspects. These experiences may hold important knowledge for both the patient and the professional in the hearing rehabilitation process.

Hyperstimulation of the immune system as a cause of autoimmune diseases

2020 ◽  
Vol 75 (3) ◽  
pp. 204-213
Author(s):  
Varvara A. Ryabkova ◽  
Leonid P. Churilov ◽  
Yehuda Shoenfeld
Keyword(s):  
Immune System ◽  
Autoimmune Diseases ◽  
Genetic Basis ◽  
Threshold Model ◽  
Subsequent Development ◽  
Threshold Effect ◽  
Successful Management ◽  
Polygenic Inheritance ◽  
Autoimmune Pathology ◽  
The Common

The pathogenesis of autoimmune diseases is very complex and multi-factorial. The concept of Mosaics of Autoimmunity was introduced to the scientific community 30 years ago by Y. Shoenfeld and D.A. Isenberg, and since then new tiles to the puzzle are continuously added. This concept specifies general pathological ideas about the multifactorial threshold model for polygenic inheritance with a threshold effect by the action of a number of external causal factors as applied to the field of autoimmunology. Among the external factors that can excessively stimulate the immune system, contributing to the development of autoimmune reactions, researchers are particularly interested in chemical substances, which are widely used in pharmacology and medicine. In this review we highlight the autoimmune dynamics i.e. a multistep pathogenesis of autoimmune diseases and the subsequent development of lymphoma in some cases. In this context several issues are addressed namely, genetic basis of autoimmunity; environmental immunostimulatory risk factors; gene/environmental interaction; pre-clinical autoimmunity with the presence of autoantibodies; and the mechanisms, underlying lymphomagenesis in autoimmune pathology. We believe that understanding the common model of the pathogenesis of autoimmune diseases is the first step to their successful management.

COPPER ALLOY No. 268

Alloy Digest ◽  
1976 ◽  
Vol 25 (2) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Copper Alloy ◽  
Cold Working ◽  
Heat Treating ◽  
Zinc Alloy ◽  
Good Resistance ◽  
Wide Range ◽  
Copper Zinc ◽  
The Common ◽  
Cold Worked

Abstract Copper Alloy No. 268 is a copper-zinc alloy with excellent cold-working properties and good resistance to corrosion. It can be cold worked by all the common fabrication processes and has a wide range of applications. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and shear strength as well as fatigue. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Cu-306. Producer or source: Brass mills.

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