scholarly journals Protogyny in a tropical damselfish: females queue for future benefit

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2198 ◽  
Author(s):  
Mark I. McCormick
Keyword(s):  
Dominance Hierarchy ◽  
Nest Site ◽  
Group Living ◽  
Trade Offs ◽  
Pomacentrus Amboinensis ◽  
Reproductive Male ◽  
The Cost ◽  
Removal Studies ◽  
Linear Dominance Hierarchy

Membership of the group is a balance between the benefits associated with group living and the cost of socially constrained growth and breeding opportunities, but the costs and benefits are seldom examined. The goal of the present study was to explore the trade-offs associated with group living for a sex-changing, potentially protogynous coral reef fish, the Ambon damselfish,Pomacentrus amboinensis. Extensive sampling showed that the species exhibits resource defence polygyny, where dominant males guard a nest site that is visited by females.P. amboinensishave a longevity of about 6.5 years on the northern Great Barrier Reef. While the species can change sex consistent with being a protogynous hermaphrodite, it is unclear the extent to which the species uses this capability. Social groups are comprised of one reproductive male, 1–7 females and a number of juveniles. Females live in a linear dominance hierarchy, with the male being more aggressive to the beta-female than the alpha-female, who exhibits lower levels of ovarian cortisol. Surveys and a tagging study indicated that groups were stable for at least three months. A passive integrated transponder tag study showed that males spawn with females from their own group, but also females from neighbouring groups.In situbehavioural observations found that alpha-females have priority of access to the nest site that the male guarded, and access to higher quality foraging areas. Male removal studies suggest that the alpha-females can change sex to take over from the male when the position becomes available. Examination of otolith microstructure showed that those individuals which change sex to males have different embryonic characteristics at hatching, suggesting that success may involve a component that is parentally endowed. The relative importance of parental effects and social organisation in affecting the importance of female queuing is yet to be studied, but will likely depend on the strength of social control by the dominant members of the group.

scholarly journals Non-random associations in group housed rats (Rattus norvegicus)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Leanne Proops ◽  
Camille A. Troisi ◽  
Tanja K. Kleinhappel ◽  
Teresa Romero
Keyword(s):  
Network Analysis ◽  
Empirical Evidence ◽  
Rattus Norvegicus ◽  
Dominance Hierarchy ◽  
Group Living ◽  
Ecological Factors ◽  
Limited Evidence ◽  
Rat Strains ◽  
Social Species ◽  
Over Time

AbstractEcological factors, such as predation, have traditionally been used to explain sociability. However, it is increasingly recognised that individuals within a group do not associate randomly, and that these non-random associations can generate fitness advantages. The majority of the empirical evidence on differentiated associations in group-living mammals, however, comes from a limited number of taxa and we still know very little about their occurrence and characteristics in some highly social species, such as rats (Rattus spp.). Here, using network analysis, we quantified association patterns in four groups of male fancy rats. We found that the associations between rats were not randomly distributed and that most individuals had significantly more preferred/avoided associates than expected by random. We also found that these preferences can be stable over time, and that they were not influenced by individuals’ rank position in the dominance hierarchy. Our findings are consistent with work in other mammals, but contrast with the limited evidence available for other rat strains. While further studies in groups with different demographic composition are warranted to confirm our findings, the occurrence of differentiated associations in all male groups of rats have important implications for the management and welfare of captive rat populations.

scholarly journals Seawater Absorption and Adhesion Properties of Hydrophobic and Superhydrophobic Thermoset Epoxy Nanocomposite Coatings

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 272
Author(s):  
Ayman M. Atta ◽  
Mohamed H. El-Newehy ◽  
Meera Moydeen Abdulhameed ◽  
Mohamed H. Wahby ◽  
Ahmed I. Hashem
Keyword(s):  
Thermal Stability ◽  
Oleic Acid ◽  
Salt Spray ◽  
Adhesion Properties ◽  
In Situ Modification ◽  
Long Time ◽  
Seawater Environment ◽  
Thermoset Epoxy ◽  
The Cost

The enhancement of both thermal and mechanical properties of epoxy materials using nanomaterials becomes a target in coating of the steel to protect it from aggressive environmental conditions for a long time, with reducing the cost. In this respect, the adhesion properties of the epoxy with the steel surfaces, and its proper superhyrophobicity to repel the seawater humidity, can be optimized via addition of green nanoparticles (NPs). In-situ modification of silver (Ag) and calcium carbonate (CaCO3) NPs with oleic acid (OA) was carried out during the formation of Ag−OA and CaCO3−OA, respectively. The epoxide oleic acid (EOA) was also used as capping for Ca−O3 NPs by in-situ method and epoxidation of Ag−OA NPs, too. The morphology, thermal stability, and the diameters of NPs, as well as their dispersion in organic solvent, were investigated. The effects of the prepared NPs on the exothermic curing of the epoxy resins in the presence of polyamines, flexibility or rigidity of epoxy coatings, wettability, and coatings durability in aggressive seawater environment were studied. The obtained results confirmed that the proper superhyrophobicity, coating adhesion, and thermal stability of the epoxy were improved after exposure to salt spray fog for 2000 h at 36 °C.

scholarly journals A framework for reducing the overhead of the quantum oracle for use with Grover’s algorithm with applications to cryptanalysis of SIKE

2020 ◽  
Vol 15 (1) ◽  
pp. 143-156
Author(s):  
Jean-François Biasse ◽  
Benjamin Pring
Keyword(s):  
Search Algorithm ◽  
Circuit Complexity ◽  
Quantum Circuit ◽  
Grover’S Algorithm ◽  
Search Problems ◽  
Trade Offs ◽  
Single Target ◽  
Grover's Algorithm ◽  
Quantum Oracle ◽  
The Cost

AbstractIn this paper we provide a framework for applying classical search and preprocessing to quantum oracles for use with Grover’s quantum search algorithm in order to lower the quantum circuit-complexity of Grover’s algorithm for single-target search problems. This has the effect (for certain problems) of reducing a portion of the polynomial overhead contributed by the implementation cost of quantum oracles and can be used to provide either strict improvements or advantageous trade-offs in circuit-complexity. Our results indicate that it is possible for quantum oracles for certain single-target preimage search problems to reduce the quantum circuit-size from $O\left(2^{n/2}\cdot mC\right)$ (where C originates from the cost of implementing the quantum oracle) to $O(2^{n/2} \cdot m\sqrt{C})$ without the use of quantum ram, whilst also slightly reducing the number of required qubits.This framework captures a previous optimisation of Grover’s algorithm using preprocessing [21] applied to cryptanalysis, providing new asymptotic analysis. We additionally provide insights and asymptotic improvements on recent cryptanalysis [16] of SIKE [14] via Grover’s algorithm, demonstrating that the speedup applies to this attack and impacting upon quantum security estimates [16] incorporated into the SIKE specification [14].

scholarly journals Wideband Rectangular Foldable and Non-foldable Antenna for Internet of Things Applications

2019 ◽  
Vol 2019 ◽  
pp. 1-5 ◽  
Author(s):  
Steve W. Y. Mung ◽  
Cheuk Yin Cheung ◽  
Ka Ming Wu ◽  
Joseph S. M. Yuen
Keyword(s):  
Internet Of Things ◽  
Printed Circuit Board ◽  
Circuit Board ◽  
Design Parameters ◽  
Multiple Frequency ◽  
Wireless Applications ◽  
Printed Circuit ◽  
Iot Applications ◽  
Trade Offs ◽  
The Cost

This article presents a simple wideband rectangular antenna in foldable and non-foldable (printed circuit board (PCB)) structures for Internet of Things (IoT) applications. Both are simple structures with two similar rectangular metal planes which cover multiple frequency bands such as GPS, WCDMA/LTE, and 2.4 GHz industrial, scientific, and medical (ISM) bands. This wideband antenna is suitable to integrate into the short- and long-range wireless applications such as the short-range 2.4 GHz ISM band and standard cellular bands. This lowers the overall size of the product as well as the cost in the applications. In this article, the configuration and operation principle are presented as well as its trade-offs on the design parameters. Simulated and experimental results of foldable and non-foldable (PCB) structures show that the antenna is suited for IoT applications.

Engaging with the science and politics of biodiversity futures: a literature review

2021 ◽  
pp. 1-8
Author(s):  
Carina Wyborn ◽  
Elena Louder ◽  
Mike Harfoot ◽  
Samantha Hill
Keyword(s):  
Human Life ◽  
Global Environmental Change ◽  
Life Forms ◽  
Trade Offs ◽  
Global Environmental ◽  
Science And Politics ◽  
Science Community ◽  
Impact On Biodiversity ◽  
Made In

Summary Future global environmental change will have a significant impact on biodiversity through the intersecting forces of climate change, urbanization, human population growth, overexploitation, and pollution. This presents a fundamental challenge to conservation approaches, which seek to conserve past or current assemblages of species or ecosystems in situ. This review canvases diverse approaches to biodiversity futures, including social science scholarship on the Anthropocene and futures thinking alongside models and scenarios from the biophysical science community. It argues that charting biodiversity futures requires processes that must include broad sections of academia and the conservation community to ask what desirable futures look like, and for whom. These efforts confront political and philosophical questions about levels of acceptable loss, and how trade-offs can be made in ways that address the injustices in the distribution of costs and benefits across and within human and non-human life forms. As such, this review proposes that charting biodiversity futures is inherently normative and political. Drawing on diverse scholarship united under a banner of ‘futures thinking’ this review presents an array of methods, approaches and concepts that provide a foundation from which to consider research and decision-making that enables action in the context of contested and uncertain biodiversity futures.

scholarly journals Black Soldier Fly Larval Valorization Benefitting from Ex-Situ Fungal Fermentation in Reducing Coconut Endosperm Waste

Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 275
Author(s):  
Chung Yiin Wong ◽  
Kunlanan Kiatkittipong ◽  
Worapon Kiatkittipong ◽  
Seteno K. O. Ntwampe ◽  
Man Kee Lam ◽  
...  
Keyword(s):  
Principal Component ◽  
Correlation Study ◽  
Statistical Correlation ◽  
Waste Reduction ◽  
Ex Situ ◽  
Larval Feeding ◽  
Rhizopus Oligosporus ◽  
Black Soldier Fly ◽  
The Cost

Oftentimes, the employment of entomoremediation to reduce organic wastes encounters ubiquitous shortcomings, i.e., ineffectiveness to valorize recalcitrant organics in wastes. Considering the cost-favorability, a fermentation process can be employed to facilitate the degradation of biopolymers into smaller organics, easing the subsequent entomoremediation process. However, the efficacy of in situ fermentation was found impeded by the black soldier fly larvae (BSFL) in the current study to reduce coconut endosperm waste (CEW). Indeed, by changing into ex situ fermentation, in which the fungal Rhizopus oligosporus was permitted to execute fermentation on CEW prior to the larval feeding, the reduction of CEW was significantly enhanced. In this regard, the waste reduction index of CEW by BSFL was almost doubled as opposed to in situ fermentation, even with the inoculation of merely 0.5 wt % of Rhizopus oligosporus. Moreover, with only 0.02 wt % of fungal inoculation size to execute the ex situ fermentation on CEW, it could spur BSFL growth by about 50%. Finally, from the statistical correlation study using principal component analysis, the presence of Rhizopus oligosporus in a range of 0.5–1.0 wt % was regarded as optimum to ferment CEW via ex situ mode, prior to the valorization by BSFL in reducing the CEW.

scholarly journals Homology-Based Interactions between Small RNAs and Their Targets Control Dominance Hierarchy of Male Determinant Alleles of Self-Incompatibility in Arabidopsis lyrata

2021 ◽  
Vol 22 (13) ◽  
pp. 6990
Author(s):  
Shinsuke Yasuda ◽  
Risa Kobayashi ◽  
Toshiro Ito ◽  
Yuko Wada ◽  
Seiji Takayama
Keyword(s):  
Dominance Hierarchy ◽  
Male Dominance ◽  
Self Incompatibility ◽  
Arabidopsis Halleri ◽  
Plant Family ◽  
Arabidopsis Lyrata ◽  
Multiple Networks ◽  
Target Sites ◽  
Gains And Losses ◽  
Linear Dominance Hierarchy

Self-incompatibility (SI) is conserved among members of the Brassicaceae plant family. This trait is controlled epigenetically by the dominance hierarchy of the male determinant alleles. We previously demonstrated that a single small RNA (sRNA) gene is sufficient to control the linear dominance hierarchy in Brassica rapa and proposed a model in which a homology-based interaction between sRNAs and target sites controls the complicated dominance hierarchy of male SI determinants. In Arabidopsis halleri, male dominance hierarchy is reported to have arisen from multiple networks of sRNA target gains and losses. Despite these findings, it remains unknown whether the molecular mechanism underlying the dominance hierarchy is conserved among Brassicaceae. Here, we identified sRNAs and their target sites that can explain the linear dominance hierarchy of Arabidopsis lyrata, a species closely related to A. halleri. We tested the model that we established in Brassica to explain the linear dominance hierarchy in A. lyrata. Our results suggest that the dominance hierarchy of A. lyrata is also controlled by a homology-based interaction between sRNAs and their targets.

Demographic life history traits of reproductive natterjack toads (Bufo calamita) vary between northern and southern latitudes

2006 ◽  
Vol 27 (3) ◽  
pp. 365-375 ◽  
Author(s):  
Delfi Sanuy ◽  
Christoph Leskovar ◽  
Neus Oromi ◽  
Ulrich Sinsch
Keyword(s):  
Life History ◽  
Life History Traits ◽  
Large Female ◽  
Breeding Period ◽  
Female Size ◽  
Data Set ◽  
Bufo Calamita ◽  
Trade Offs ◽  
Age Variation ◽  
The Cost

AbstractDemographic life history traits were investigated in three Bufo calamita populations in Germany (Rhineland-Palatinate: Urmitz, 50°N; 1998-2000) and Spain (Catalonia: Balaguer, Mas de Melons, 41°N; 2004). We used skeletochronology to estimate the age as number of lines of arrested growth in breeding adults collected during the spring breeding period (all localities) and during the summer breeding period (only Urmitz). A data set including the variables sex, age and size of 185 males and of 87 females was analyzed with respect to seven life history traits (age and size at maturity of the youngest first breeders, age variation in first breeders, longevity, potential reproductive lifespan, median lifespan, age-size relationship). Spring and summer cohorts at the German locality differed with respect to longevity and potential reproductive lifespan by one year in favour of the early breeders. The potential consequences on fitness and stability of cohorts are discussed. Latitudinal variation of life history traits was mainly limited to female natterjacks in which along a south-north gradient longevity and potential reproductive lifespan increased while size decreased. These results and a review of published information on natterjack demography suggest that lifetime number of offspring seem to be optimized by locally different trade-offs: large female size at the cost of longevity in southern populations and increased longevity at the cost of size in northern ones.

Sustainable Distribution Design: Contrasting Disposable, Recyclable, and Reusable Strategies for Packaging Materials Using a Total Cost Analysis With an Illustration of Milk Distribution

2010 ◽  
Author(s):  
Sri Satya Kanaka Nagendra Jayanty ◽  
William J. Sawaya ◽  
Michael D. Johnson
Keyword(s):  
Cost Benefit ◽  
Packaging Materials ◽  
Policy Makers ◽  
Specific Product ◽  
Cost Structures ◽  
Trade Offs ◽  
Technological Advances ◽  
The Cost ◽  
Total Cost Analysis ◽  
Plastic Containers

Engineers, policy makers, and managers have shown increasing interest in increasing the sustainability of products over their complete lifecycles and also from the ‘cradle to grave’ or from production to the disposal of each specific product. However, a significant amount of material is disposed of in landfills rather than being reused in some form. A sizeable proportion of the products being dumped in landfills consist of packaging materials for consumable products. Technological advances in plastics, packaging, cleaning, logistics, and new environmental awareness and understanding may have altered the cost structures surrounding the lifecycle use and disposal costs of many materials and products resulting in different cost-benefit trade-offs. An explicit and well-informed economic analysis of reusing certain containers might change current practices and results in significantly less waste disposal in landfills and in less consumption of resources for manufacturing packaging materials. This work presents a method for calculating the costs associated with a complete process of implementing a system to reuse plastic containers for food products. Specifically, the different relative costs of using a container and then either disposing of it in a landfill, recycling the material, or reconditioning the container for reuse and then reusing it are compared explicitly. Specific numbers and values are calculated for the case of plastic milk bottles to demonstrate the complicated interactions and the feasibility of such a strategy.

scholarly journals Problem Faced by Precast Industry to Implement in Residential Construction

2020 ◽  
Vol 9 (5) ◽  
pp. 2394-2396
Keyword(s):  
Residential Construction ◽  
Joint Stability ◽  
Standard Size ◽  
Research Survey ◽  
Technical Issues ◽  
Storage Area ◽  
Standard Rate ◽  
The Cost ◽  
Cost Of Construction

The Precast industry is booming industry now a day, but then also the implementation ratio of precast member in residential construction work is not up to the mark. As we all know that precast having numerous advantages over the cast in situ construction method, for example it saves the total time of construction which indirectly reduces the cost of construction but still we are lagging behind in implementation of precast in it. In this research we have listed out some problem which can be cause of less implementation of precast in residential construction buildings. As discussed in paper, there are so many factors are affected on Implementation of Precast in Residential Construction Sector For example: Technical Issues and General Issues. In Technical Issues Joint stability problem during Erection, Standard size of precast element, Leakage Issues, Design change related problem, Requirement of Standard Rate per Panel, End user Profit, Additional Taxes, General Issues are: Transportation of Precast Element, Loading and Unloading problems, Transportation to sight, Storage Area, Skilled Labour Research has done and data is collected through Questionery survey, Field survey, and research survey.

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