scholarly journals Development and Evolution of Unisexual Flowers: A Review

Plants ◽  
2022 ◽  
Vol 11 (2) ◽  
pp. 155
Author(s):  
Florian Jabbour ◽  
Felipe Espinosa ◽  
Quentin Dejonghe ◽  
Timothée Le Péchon
Keyword(s):  
Developmental Stages ◽  
Quantitative Description ◽  
Developmental Rate ◽  
Developmental Studies ◽  
Two Dimensional ◽  
Sexual Systems ◽  
Unisexual Flowers ◽  
Evo Devo ◽  
First Time ◽  
Development And Evolution

The development of unisexual flowers has been described in a large number of taxa, sampling the diversity of floral phenotypes and sexual systems observed in extant angiosperms, in studies focusing on floral ontogeny, on the evo-devo of unisexuality, or on the genetic and chromosomal bases of unisexuality. We review here such developmental studies, aiming at characterizing the diversity of ontogenic pathways leading to functionally unisexual flowers. In addition, we present for the first time and in a two-dimensional morphospace a quantitative description of the developmental rate of the sexual organs in functionally unisexual flowers, in a non-exhaustive sampling of angiosperms with contrasted floral morphologies. Eventually, recommendations are provided to help plant evo-devo researchers and botanists addressing macroevolutionary and ecological issues to more precisely select the taxa, the biological material, or the developmental stages to be investigated.

Serial Homology as a Challenge to Evolutionary Theory

2017 ◽  
Author(s):  
Stéphane Schmitt
Keyword(s):  
Biological Sciences ◽  
Evolutionary Theory ◽  
Serial Homology ◽  
The Core ◽  
Long Period ◽  
Colonial Theory ◽  
Experimental Approaches ◽  
Evo Devo ◽  
The 19Th Century ◽  
Development And Evolution

The problem of the repeated parts of organisms was at the center of the biological sciences as early as the first decades of the 19th century. Some concepts and theories (e.g., serial homology, unity of plan, or colonial theory) introduced in order to explain the similarity as well as the differences between the repeated structures of an organism were reused throughout the 19th and the 20th century, in spite of the fundamental changes during this long period that saw the diffusion of the evolutionary theory, the rise of experimental approaches, and the emergence of new fields and disciplines. Interestingly, this conceptual heritage was at the core of any attempt to unify the problems of inheritance, development, and evolution, in particular in the last decades, with the rise of “evo-devo.” This chapter examines the conditions of this theoretical continuity and the challenges it brings out for the current evolutionary sciences.

scholarly journals Influence of a Standing Wave Flow-Field on the Dynamics of a Spray Diffusion Flame

Fluids ◽  
2021 ◽  
Vol 6 (1) ◽  
pp. 27
Author(s):  
J. Barry Greenberg ◽  
David Katoshevski
Keyword(s):  
Liquid Phase ◽  
Flow Field ◽  
Standing Wave ◽  
Diffusion Flame ◽  
Stokes Number ◽  
Flame Height ◽  
Wave Flow ◽  
Two Dimensional ◽  
Governing Equations ◽  
First Time

A theoretical investigation of the influence of a standing wave flow-field on the dynamics of a laminar two-dimensional spray diffusion flame is presented for the first time. The mathematical analysis permits mild slip between the droplets and their host surroundings. For the liquid phase, the use of a small Stokes number as the perturbation parameater enables a solution of the governing equations to be developed. Influence of the standing wave flow-field on droplet grouping is described by a specially constructed modification of the vaporization Damkohler number. Instantaneous flame front shapes are found via a solution for the usual Schwab–Zeldovitch parameter. Numerical results obtained from the analytical solution uncover the strong bearing that droplet grouping, induced by the standing wave flow-field, can have on flame height, shape, and type (over- or under-ventilated) and on the existence of multiple flame fronts.

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

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.

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

Agronomy ◽  
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.

scholarly journals Tetrazine molecules as efficient electronic diversion channel in 2D organic-inorganic perovskites

2021 ◽  
Author(s):  
Ferdinand Lédée ◽  
Pierre Audebert ◽  
Gaëlle Trippé-Allard ◽  
Laurent Galmiche ◽  
Damien Garrot ◽  
...  
Keyword(s):  
Organic Component ◽  
Two Dimensional ◽  
Diversion Channel ◽  
Halide Perovskites ◽  
First Time

We present the synthesis of two novel two-dimensional (2D) hybrid organic-inorganic halide perovskites incorporating for the first time 100% of a photoactive tetrazine derivative as the organic component. With this...

scholarly journals Exfoliation in a low boiling point solvent and electrochemical applications of MoO3

2020 ◽  
Vol 11 ◽  
pp. 662-670
Author(s):  
Matangi Sricharan ◽  
Bikesh Gupta ◽  
Sreejesh Moolayadukkam ◽  
H S S Ramakrishna Matte
Keyword(s):  
Energy Storage ◽  
Electrode Material ◽  
Electronic Devices ◽  
High Specific Capacitance ◽  
Two Dimensional ◽  
Energy Storage Devices ◽  
Intrinsic Nature ◽  
Storage Devices ◽  
Scan Rate ◽  
First Time

MoO3 is a versatile two-dimensional transition metal oxide having applications in areas such as energy storage devices, electronic devices and catalysis. To efficiently utilize the properties of MoO3 arising from its two-dimensional nature exfoliation is necessary. In this work, the exfoliation of MoO3 is carried out in 2-butanone for the first time. The achieved concentration of the dispersion is about 0.57 mg·mL−1 with a yield of 5.7%, which are the highest values reported to date. These high values of concentration and yield can be attributed to a favorable matching of energies involved in exfoliation and stabilization of MoO3 nanosheets in 2-butanone. Interestingly, the MoO3 dispersion in 2-butanone retains its intrinsic nature even after exposure to sunlight for 24 h. The composites of MoO3 nanosheets were used as an electrode material for supercapacitors and showed a high specific capacitance of 201 F·g−1 in a three-electrode configuration at a scan rate of 50 mV·s−1.

scholarly journals Salmonella Typhi and Salmonella Paratyphi A elaborate distinct systemic metabolite signatures during enteric fever

eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Elin Näsström ◽  
Nga Tran Vu Thieu ◽  
Sabina Dongol ◽  
Abhilasha Karkey ◽  
Phat Voong Vinh ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Bacterial Infections ◽  
Enteric Fever ◽  
Salmonella Typhi ◽  
Two Dimensional ◽  
Flight Mass Spectrometry ◽  
Metabolite Profiles ◽  
Diagnostic Approaches ◽  
First Time

The host–pathogen interactions induced by Salmonella Typhi and Salmonella Paratyphi A during enteric fever are poorly understood. This knowledge gap, and the human restricted nature of these bacteria, limit our understanding of the disease and impede the development of new diagnostic approaches. To investigate metabolite signals associated with enteric fever we performed two dimensional gas chromatography with time-of-flight mass spectrometry (GCxGC/TOFMS) on plasma from patients with S. Typhi and S. Paratyphi A infections and asymptomatic controls, identifying 695 individual metabolite peaks. Applying supervised pattern recognition, we found highly significant and reproducible metabolite profiles separating S. Typhi cases, S. Paratyphi A cases, and controls, calculating that a combination of six metabolites could accurately define the etiological agent. For the first time we show that reproducible and serovar specific systemic biomarkers can be detected during enteric fever. Our work defines several biologically plausible metabolites that can be used to detect enteric fever, and unlocks the potential of this method in diagnosing other systemic bacterial infections.

scholarly journals Structural Transitions at Microtubule Ends Correlate with Their Dynamic Properties in Xenopus Egg Extracts

2000 ◽  
Vol 149 (4) ◽  
pp. 767-774 ◽  
Author(s):  
Isabelle Arnal ◽  
Eric Karsenti ◽  
Anthony A. Hyman
Keyword(s):  
Dynamic Instability ◽  
Dynamic Properties ◽  
Microtubule Assembly ◽  
Two Dimensional ◽  
Egg Extracts ◽  
Xenopus Egg ◽  
Xenopus Egg Extracts ◽  
First Time ◽  
The Relationship ◽  
Dynamic Populations

Microtubules are dynamically unstable polymers that interconvert stochastically between growing and shrinking states by the addition and loss of subunits from their ends. However, there is little experimental data on the relationship between microtubule end structure and the regulation of dynamic instability. To investigate this relationship, we have modulated dynamic instability in Xenopus egg extracts by adding a catastrophe-promoting factor, Op18/stathmin. Using electron cryomicroscopy, we find that microtubules in cytoplasmic extracts grow by the extension of a two- dimensional sheet of protofilaments, which later closes into a tube. Increasing the catastrophe frequency by the addition of Op18/stathmin decreases both the length and frequency of the occurrence of sheets and increases the number of frayed ends. Interestingly, we also find that more dynamic populations contain more blunt ends, suggesting that these are a metastable intermediate between shrinking and growing microtubules. Our results demonstrate for the first time that microtubule assembly in physiological conditions is a two-dimensional process, and they suggest that the two-dimensional sheets stabilize microtubules against catastrophes. We present a model in which the frequency of catastrophes is directly correlated with the structural state of microtubule ends.

New Hopane Triterpenoids From Lichens in the Family Physiaceae

1989 ◽  
Vol 42 (8) ◽  
pp. 1415 ◽  
Author(s):  
AL Wilkins ◽  
JA Elix ◽  
KL Gaul ◽  
R Moberg
Keyword(s):  
Methyl Ester ◽  
Natural Occurrence ◽  
Two Dimensional ◽  
Triterpene Acid ◽  
The Family ◽  
First Time

Three new hopane triterpenes have been isolated from lichens of the family Physciaceae. Two of the triterpenes, 22-hydroxyhopan-6-one (2) and 6 α-acetoxyhopan-22-ol (1b), have been characterized previously but their natural occurrence is reported for the first time, while a new triterpene acid [ aipolic acid (1c)], was isolated and characterized as the corresponding methyl ester. One- and two-dimensional 1H-1H and 13C-lH correlated n.m.r. studies have revealed methyl aipolate to be methyl 6#945;-acetoxy-22-hydroxyhopan-25-oate (1d).

I2-induced SC–SC transformation within two-dimensional Zn(ii)-triazole framework: an ideal detector of cyano-containing molecules

2016 ◽  
Vol 52 (15) ◽  
pp. 3099-3102 ◽  
Author(s):  
Ying Wang ◽  
Jin-Min Yi ◽  
Meng-Yuan Zhang ◽  
Ping Xu ◽  
Xiao-Jun Zhao
Keyword(s):  
Transformation Process ◽  
Two Dimensional ◽  
Ideal Detector ◽  
First Time ◽  
2D Network ◽  
Selective Sensor

A SC–SC transformation process driven by I2 has been shown to generate a 2D + 1D → 2D interpenetrated architecture from a 2D + 2D → 2D network. For the first time we demonstrate a selective sensor toward cyano-containing molecules.

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