Embryonic Onset of Sexually Dimorphic Heart Rates in the Viviparous Fish, Gambusia holbrooki

In fish, little is known about sex-specific differences in physiology and performance of the heart and whether these differences manifest during development. Here for the first time, the sex-specific heart rates during embryogenesis of Gambusia holbrooki, from the onset of the heart rates (HRs) to just prior to parturition, was investigated using light cardiogram. The genetic sex of the embryos was post-verified using a sex-specific genetic marker. Results reveal that heart rates and resting time significantly increase (p < 0.05) with progressive embryonic development. Furthermore, both ventricular and atrial frequencies of female embryos were significantly higher (p < 0.05) than those of their male sibs at the corresponding developmental stages and remained so at all later developmental stages (p < 0.05). In concurrence, the heart rate and ventricular size of the adult females were also significantly (p < 0.05) higher and larger respectively than those of males. Collectively, the results suggest that the cardiac sex-dimorphism manifests as early as late-organogenesis and persists through adulthood in this species. These findings suggest that the cardiac measurements can be employed to non-invasively sex the developing embryos, well in advance of when their phenotypic sex is discernible. In addition, G. holbrooki could serve as a better model to study comparative vertebrate cardiovascular development as well as to investigate anthropogenic and climatic impacts on heart physiology of this species, that may be sex influenced.

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Dynamics of sex-biased gene expression over development in the stick insect Timema californicum

10.1101/2021.01.23.427895 ◽

2021 ◽

Author(s):

Jelisaveta Djordjevic ◽

Zoé Dumas ◽

Marc Robinson-Rechavi ◽

Tanja Schwander ◽

Darren James Parker

Keyword(s):

Gene Expression ◽

Sexual Dimorphism ◽

Developmental Stages ◽

Adult Stage ◽

Stick Insect ◽

Sexually Dimorphic ◽

Rna Seq ◽

Hemimetabolous Insect ◽

First Time ◽

Early Developmental

AbstractSexually dimorphic phenotypes are thought to arise primarily from sex-biased gene expression during development. Major changes in developmental strategies, such as the shift from hemimetabolous to holometabolous development, are therefore expected to have profound consequences for the dynamics of sex-biased gene expression. However, no studies have previously examined sex-biased gene expression over development in hemimetabolous insects, precluding comparisons between developmental strategies. Here we characterized sex-biased gene expression at three developmental stages in a hemimetabolous stick insect (Timema californicum): hatchlings, juveniles, and adults. As expected, the proportion of sex-biased genes gradually increased over development. Sex-biased genes identified at early developmental stages were generally consistently male- or female-biased at later stages, suggesting their importance in sexual differentiation. We then compared the dynamics of sex-biased gene expression over development in T. californicum to those of the holometabolous fly Drosophila melanogaster by reanalyzing publicly available RNA-seq data from third instar larval, pupal and adult stages. In D. melanogaster, sex-biased gene expression increases abruptly at the adult stage when morphological sexual dimorphism is manifested. This supports the prediction that sex-biased gene expression mirrors phenotypic sexual dimorphism. Our study details for the first time the dynamics of sex-biased gene expression over development in a hemimetabolous insect and suggests that these dynamics differ extensively between holometabolous and hemimetabolous species.

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Redescription of Pseudanuretes chaetodontis Yamaguti, 1936 (Copepoda, Siphonostomatoida, Caligidae) and description of some of its developmental stages, with a discussion on sexually dimorphic features in the genus

Crustaceana ◽

10.1163/15685403-00003897 ◽

2019 ◽

Vol 92 (5) ◽

pp. 599-612

Author(s):

Kunihiko Izawa

Keyword(s):

Developmental Stages ◽

Sexually Dimorphic ◽

Female Specimen ◽

Free Living ◽

Male Type ◽

First Time

Abstract Pseudanuretes chaetodontis Yamaguti, 1936 is redescribed based on both sexes, from specimens recovered from the branchial lamellae of Chaetodontoplus septentrionalis (Temminck & Schlegel, 1844) (Pisces, Pomacanthidae) in Japan. In addition, both sexes of copepodid V are described, as well as the free-living phase composed of two naupliar stages and the infective copepodid I stage, all reared from eggs, for the first time. Sexually dimorphic features found in the adult are discussed and it is pointed out herein that P. parvulus (Wilson, 1913) was described based on a copepodid V female specimen by that original author. Both sexes of the copepodid V exhibit sexually dimorphic features of the male type, i.e., in the maxilliped and in leg 5.

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“Little Trio” for clarinet, bassoon and piano

Musical art in the educological discourse ◽

10.28925/2518-766x.2018.3.7579 ◽

2018 ◽

pp. 75-79

Author(s):

N. Yakovchuk

Keyword(s):

Chamber Music ◽

Instrumental Music ◽

Instrumental Ensemble ◽

Interesting Phenomenon ◽

Theoretical Understanding ◽

Classical Traditions ◽

And Performance ◽

Instrumental Ensembles ◽

Written Compositions ◽

First Time

The chamber-instrumental ensemble music in the Ukrainian musical culture of the last third of the 20th and the beginning of the 21st centuries occupies one of the leading places and is characterized by powerful processes in its development. Such circumstances caused the Ukrainian musicologist interests to the problems of chamber-instrumental music creativity and performance. There are appeared researches in the field of theory, history and performance problems covering the most important questions like chamber music definitions, specific genre issues, the growing function of piano in the Ukrainian chamber music, the increasing questions of technique and timbre importance of modern instrumental ensembles. In the significant multifaceted creative work of contemporary Ukrainian composer, Oleksandr Yakovchuk, the genre of chamber instrumental ensemble music represents a complex and interesting phenomenon. Original and skillfully written compositions reflect artistic world of the composer of postmodern time and gained recognition in music life of Ukraine and beyond. These works are highly appreciated in performing practice of our days. The purpose of the article is to analyze the work — “Little Trio” for clarinet, bassoon and piano (1980), which has the signs of neoclassical tendency in the composer’s style. The methodological basis of this research is a comprehensive approach in theoretical understanding of the subject of research (the methods of textology, source study as well as the method of interviewing the author were used). The scientific novelty of this article is in the priority of its main provisions, since the “Little Trio” entered the scientific circulation for the first time. The three-movement “Little Trio” (1980) is notable for the light feeling of timbre colours and the shape clarity. The Ist movement — Allegretto giocoso — is written in a sonata form following all classical traditions. Quite interesting are the two monologues of clarinet and bassoon from the IInd movement, they represent very modern line in Ukrainian chamber music — the possibility of sincere confession which comes through the solo cadence. In the IIIrd movement, the composer took advantage from the folk Ukrainian dance “hopak” using the rhythm of it and creating dance character of the Final.

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Do Accounting Faculty Characteristics Impact CPA Exam Performance? An Investigation of Nearly 700,000 Examinations

Issues in Accounting Education ◽

10.2308/iace-51227 ◽

2015 ◽

Vol 31 (3) ◽

pp. 291-300 ◽

Cited By ~ 12

Author(s):

Dennis M. Bline ◽

Stephen Perreault ◽

Xiaochuan Zheng

Keyword(s):

Exam Performance ◽

Faculty Research ◽

Pass Rates ◽

Accounting Faculty ◽

Research And Teaching ◽

Faculty Characteristics ◽

Cpa Exam ◽

Faculty Research Productivity ◽

And Performance ◽

First Time

ABSTRACT While many colleges and universities publicize CPA examination pass rates as evidence of having a high-quality accounting program, some have questioned whether program-specific characteristics are legitimate predictors of examination success. To examine this issue, we empirically investigate the link between accounting faculty characteristics and performance on the CPA examination. We examine the results from nearly 700,000 first-time exam sittings taken during the period 2005–2013 and find that faculty research and teaching specialization has a significant impact on CPA exam performance. That is, when a program has a relatively higher percentage of accounting faculty with expertise in a particular content area tested on the exam (e.g., auditing), graduates achieve higher scores on the related exam section (e.g., AUD). We also find that faculty research productivity and CPA certification status are positively related to candidate exam performance. We believe these results contribute to the existing literature on the determinants of CPA exam success and also provide important insights to those responsible for accounting faculty staffing and development.

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Probing the floral developmental stages, bisexuality and sex reversions in castor (Ricinus communis L.)

Scientific Reports ◽

10.1038/s41598-021-81781-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sujatha Thankeswaran Parvathy ◽

Amala Joseph Prabakaran ◽

Thadakamalla Jayakrishna

Keyword(s):

Developmental Stages ◽

Ricinus Communis ◽

Sex Expression ◽

Pistil Abortion ◽

Ricinus Communis L ◽

Sex Reversion ◽

Stage 4 ◽

Meristem Development ◽

Male Specific ◽

First Time

AbstractCastor (Ricinus communis L) is an ideal model species for sex mechanism studies in monoecious angiosperms, due to wide variations in sex expression. Sex reversion to monoecy in pistillate lines, along with labile sex expression, negatively influences hybrid seed purity. The study focuses on understanding the mechanisms of unisexual flower development, sex reversions and sex variations in castor, using various genotypes with distinct sex expression pattern. Male and female flowers had 8 and 12 developmental stages respectively, were morphologically similar till stage 4, with an intermediate bisexual state and were intermediate between type 1 and type 2 flowers. Pistil abortion was earlier than stamen inhibition. Sex alterations occurred at floral and inflorescence level. While sex-reversion was unidirectional towards maleness via bisexual stage, at high day temperatures (Tmax > 38 °C), femaleness was restored with subsequent drop in temperatures. Temperature existing for 2–3 weeks during floral meristem development, influences sexuality of the flower. We report for first time that unisexuality is preceded by bisexuality in castor flowers which alters with genotype and temperature, and sex reversions as well as high sexual polymorphisms in castor are due to alterations in floral developmental pathways. Differentially expressed (male-abundant or male-specific) genes Short chain dehydrogenase reductase 2a (SDR) and WUSCHEL are possibly involved in sex determination of castor.

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Combining QTL Mapping and Gene Expression Analysis to Elucidate the Genetic Control of ‘Crumbly’ Fruit in Red Raspberry (Rubus idaeus L.)

Agronomy ◽

10.3390/agronomy11040794 ◽

2021 ◽

Vol 11 (4) ◽

pp. 794

Author(s):

Luca M. Scolari ◽

Robert D. Hancock ◽

Pete E. Hedley ◽

Jenny Morris ◽

Kay Smith ◽

...

Keyword(s):

Genetic Control ◽

Developmental Disorder ◽

Molecular Mechanisms ◽

Developmental Stages ◽

Microarray Experiment ◽

Rubus Idaeus ◽

Red Raspberry ◽

Genotype By Sequencing ◽

First Time ◽

Selection Of

‘Crumbly’ fruit is a developmental disorder in raspberry that results in malformed and unsaleable fruits. For the first time, we define two distinct crumbly phenotypes as part of this work. A consistent crumbly fruit phenotype affecting the majority of fruits every season, which we refer to as crumbly fruit disorder (CFD) and a second phenotype where symptoms vary across seasons as malformed fruit disorder (MFD). Here, segregation of crumbly fruit of the MFD phenotype was examined in a full-sib family and three QTL (Quantitative Trait Loci) were identified on a high density GbS (Genotype by Sequencing) linkage map. This included a new QTL and more accurate location of two previously identified QTLs. A microarray experiment using normal and crumbly fruit at three different developmental stages identified several genes that were differentially expressed between the crumbly and non-crumbly phenotypes within the three QTL. Analysis of gene function highlighted the importance of processes that compromise ovule fertilization as triggers of crumbly fruit. These candidate genes provided insights regarding the molecular mechanisms involved in the genetic control of crumbly fruit in red raspberry. This study will contribute to new breeding strategies and diagnostics through the selection of molecular markers associated with the crumbly trait.

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Identification, Expression and Evolution of Short-Chain Dehydrogenases/Reductases in Nile Tilapia (Oreochromis niloticus)

International Journal of Molecular Sciences ◽

10.3390/ijms22084201 ◽

2021 ◽

Vol 22 (8) ◽

pp. 4201

Author(s):

Shuai Zhang ◽

Lang Xie ◽

Shuqing Zheng ◽

Baoyue Lu ◽

Wenjing Tao ◽

...

Keyword(s):

Transcriptome Analysis ◽

Tandem Duplication ◽

Developmental Stages ◽

Short Chain ◽

Sexually Dimorphic ◽

Physiological Processes ◽

Genome Wide ◽

Nile Tilapia Oreochromis Niloticus ◽

Tandem Duplications

The short-chain dehydrogenases/reductases (SDR) superfamily is involved in multiple physiological processes. In this study, genome-wide identification and comprehensive analysis of SDR superfamily were carried out in 29 animal species based on the latest genome databases. Overall, the number of SDR genes in animals increased with whole genome duplication (WGD), suggesting the expansion of SDRs during evolution, especially in 3R-WGD and polyploidization of teleosts. Phylogenetic analysis indicated that vertebrates SDRs were clustered into five categories: classical, extended, undefined, atypical, and complex. Moreover, tandem duplication of hpgd-a, rdh8b and dhrs13 was observed in teleosts analyzed. Additionally, tandem duplications of dhrs11-a, dhrs7a, hsd11b1b, and cbr1-a were observed in all cichlids analyzed, and tandem duplication of rdh10-b was observed in tilapiines. Transcriptome analysis of adult fish revealed that 93 SDRs were expressed in more than one tissue and 5 in one tissue only. Transcriptome analysis of gonads from different developmental stages showed that expression of 17 SDRs were sexually dimorphic with 11 higher in ovary and 6 higher in testis. The sexually dimorphic expressions of these SDRs were confirmed by in situ hybridization (ISH) and qPCR, indicating their possible roles in steroidogenesis and gonadal differentiation. Taken together, the identification and the expression data obtained in this study contribute to a better understanding of SDR superfamily evolution and functions in teleosts.

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Heart Rate and Performance in Manual Missile Guidance

Perceptual and Motor Skills ◽

10.2466/pms.1971.32.2.352 ◽

1971 ◽

Vol 32 (2) ◽

pp. 352-354

Author(s):

Bengt Bergstroem ◽

Peter Arnberg

Keyword(s):

Heart Rate ◽

Performance Data ◽

Tracking Performance ◽

Missile Guidance ◽

Heart Rates ◽

Laboratory Conditions ◽

Stress Studies ◽

And Performance

Earlier stress studies under laboratory conditions show that heart rates from 100 to 110 bpm are associated with significant decrements in missile-tracking performance. Data from real missile tracking by 8 operators with no stress deliberately induced indicate, however, that performance is unaffected up to 135 bpm, and only moderately affected in the 135- to 170-bpm region. The disagreement between the two sets of results highlights the difficulties in generalizing from stress experiments.

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Unique hooks in the male scaled squid Lepidoteuthis grimaldi

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315403008324h ◽

2003 ◽

Vol 83 (5) ◽

pp. 1099-1100 ◽

Cited By ~ 7

Author(s):

George D. Jackson ◽

Steve O'Shea

Keyword(s):

Sexually Dimorphic ◽

First Time

The male scaled squid Lepidoteuthis grimaldii hereby reported for the first time, is equipped with a pair of grossly enlarged sabre-like hooks. These unique hooks, found only on males, are without parallel amongst cephalopods. As a sexually dimorphic character, they are more likely to be involved in reproduction than predation.

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Association between Participation in an Intensive Longitudinal Assessment Program and Performance on a Cognitive Examination in the Maintenance of Certification in Anesthesiology Program®

Anesthesiology ◽

10.1097/aln.0000000000001301 ◽

2016 ◽

Vol 125 (5) ◽

pp. 1046-1055 ◽

Cited By ~ 13

Author(s):

Huaping Sun ◽

Yan Zhou ◽

Deborah J. Culley ◽

Cynthia A. Lien ◽

Ann E. Harman ◽

...

Keyword(s):

North Carolina ◽

Learning Resources ◽

Longitudinal Assessment ◽

Immediate Feedback ◽

High Stakes ◽

Web Based ◽

Maintenance Of Certification ◽

Improved Performance ◽

And Performance ◽

First Time

Abstract Background As part of the Maintenance of Certification in Anesthesiology Program® (MOCA®), the American Board of Anesthesiology (Raleigh, North Carolina) developed the MOCA Minute program, a web-based intensive longitudinal assessment involving weekly questions with immediate feedback and links to learning resources. This observational study tested the hypothesis that individuals who participate in the MOCA Minute program perform better on the MOCA Cognitive Examination (CE) compared with those who do not participate. Methods Two separate cohorts of individuals eligible for July 2014 and January 2015 CEs were invited to participate in this pilot. The CE scores for each cohort were compared between those who did and did not participate, controlling for the factors known to affect performance. For the first cohort, examination performances for topics covered and not covered by the MOCA Minute were analyzed separately. Results Six hundred sixteen diplomates in July 2014 and 684 diplomates in January 2015 took the CE for the first time. In multiple regression analysis, those actively participating scored 9.9 points (95% CI, 0.8 to 18.9) and 9.3 points (95% CI, 2.3 to 16.3) higher when compared with those not enrolled, respectively. Compared to the group that did not enroll in MOCA Minute, those who enrolled but did not actively participate demonstrated no improvement in scores. MOCA Minute participation was associated with improvement in both questions covering topics included the MOCA Minute and questions not covering these topics. Conclusions This analysis provides evidence that voluntary active participation in a program featuring frequent knowledge assessments accompanied by targeted learning resources is associated with improved performance on a high-stakes CE.

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