scholarly journals Up and to the light: intra- and interspecific variability of photo- and geo-tactic oviposition preferences in genus Trichogramma

2021 ◽  
Author(s):  
Guy Perez ◽  
Victor Burte ◽  
Faten Ayed ◽  
Geraldine Groussier ◽  
louise van Oudenhove ◽  
...  
Keyword(s):  
Experimental Approach ◽  
Oviposition Preference ◽  
Resource Depletion ◽  
Time Preferences ◽  
Environmental Cues ◽  
Biological Control Agents ◽  
Careful Evaluation ◽  
Oviposition Preferences ◽  
And Behavior ◽  
Selection Of

Trichogramma are parasitic microwasps much used as biological control agents. The genus is known to harbor tremendous diversity, both inter- and intra-specific. The successful selection of appropriate strains rests on a careful evaluation of this diversity at the phenotypic level, especially regarding oviposition performance and behavior. Oviposition preferences in relation to environmental cues such as light and gravity, although suspected to play an important role in microhabitat selection and oviposition patterns, have received little attention so far in this group, either alone or in combination. The extent of their variability is thus virtually unknown. Here we use a novel experimental approach relying on automatic image analysis to characterize the oviposition preferences in relation to light, gravity, and their interaction, in 25 populations of Trichogramma from five species. We show that most Trichogramma populations and species harbour preferences for light and preferences for elevated parts. However, the two trait harbor significant inter and intraspecific variation. The effects of light and gravity on oviposition patterns were found to be almost perfectly additive overall, with two exceptions. Oviposition preference patterns were not static but very plastic in time: preferences tended to relax over consecutive days, and the strongest preferences relaxed the fastest, presumably because of the density-dependent effect of resource depletion. A correlation of oviposition patterns with the vegetation stratum at which populations were sampled suggests that different species/populations may be associated with different strata with corresponding differentiation in light- and gravity-related oviposition preferences.

A Theoretical and Experimental Approach to E-pH Diagram for the Niobium-Water System

CORROSION ◽  
10.5006/3871 ◽  
2021 ◽  
Author(s):  
Rodney Santandrea ◽  
Simone BRASIL ◽  
Leila Reznik ◽  
Ladimir Carvalho ◽  
Luiz Miranda
Keyword(s):  
Experimental Approach ◽  
Ph Monitoring ◽  
Aqueous Media ◽  
Water System ◽  
Chemical Species ◽  
Polarization Curves ◽  
Buffer Solutions ◽  
Excellent Corrosion Resistance ◽  
Experimental Diagram ◽  
Selection Of

E-pH diagrams are usually built from thermodynamic databases available in the literature or from specific software. However, depending on the conditions and the chemical species defined for elaborating a diagram, it may present completely different immunity, passivation, and corrosion domains. In order to obtain a result closer to a real system, experimental E-pH diagrams can be built from polarization curves obtained in the evaluated conditions. This work discloses the construction of a diagram for the Nb-H<sub>2</sub>O system at 25°C from theoretical study and the specific selection of chemical species in the solutions through computer simulations. The polarization curves for the construction of the experimental diagram were gathered without the use of buffer solutions and under pH monitoring in the solution bulk throughout all assays. The methodology proposed was considered adequate since, from experimental data, a final result compatible with the classic diagram for the Nb-H<sub>2</sub>O system and the excellent corrosion resistance of niobium in aqueous media were achieved.

Digging deep? Digging more? A research on the influence of corporate CSR theme consistency strategy

2018 ◽  
Vol 1 (1) ◽  
pp. 76-93 ◽  
Author(s):  
Yang Zhang ◽  
Xuhui Wang ◽  
Yingying Shen
Keyword(s):  
Communication Channel ◽  
Information Dissemination ◽  
Focal Point ◽  
Social Programs ◽  
Business Practices ◽  
Content Type ◽  
Moderation Effect ◽  
Corporate Social ◽  
And Behavior ◽  
Selection Of

PurposeAs the focal point of both academic studies and business practices, the theme strategy of corporate social responsibility (CSR) arouses wide attention. However, extant studies concentrate more on the selection of the theme of CSR activities, such as the fitness between CSR activities and the core business, thus largely neglecting the consistency of the theme. The purpose of this paper is to determine whether the enterprise should adopt a consistent theme strategy or should participate in different social programs, and how do customers response to the lack of studies in different theme-consistent strategies.Design/methodology/approachIn this paper, two progressive experiments are performed. The purpose of study 1 is to examine the influence of theme consistency on consumers’ CSR association and how consumers’ attribution to corporation motivation mediates such impacts. The purpose for study 2 is to examine whether information dissemination channels and cooperation with public organization could affect the influence of theme consistency strategy.FindingsThe significant influences of theme consistency on consumer CSR association was demonstrated, and consumer’s perceived motivation of CSR was found to play the mediation role. Moreover, the moderation effect of the communication channel of CSR information was found to be important to strengthen the influence of the theme-consistent strategy.Originality/valueThis paper not only demonstrates the influence of theme consistency, but also explains how theme consistency influences consumers’ attitude and behavior. It enriches the study on the antecedent variables of consumers’ attribution to corporate motivation.

Bacteriophages: from isolation to application

2021 ◽  
Vol 22 ◽  
Author(s):  
Abdallah S. Abdelsattar ◽  
Alyaa Dawoud ◽  
Salsabil Makky ◽  
Rana Nofal ◽  
Ramy K. Aziz ◽  
...  
Keyword(s):  
Food Industry ◽  
Pathogenic Bacteria ◽  
Phage Genome ◽  
Morphological Structure ◽  
High Specificity ◽  
Potential Alternative ◽  
And Behavior ◽  
Phage Isolation ◽  
Different Levels ◽  
Selection Of

: Bacteriophages are considered as a potential alternative to fight pathogenic bacteria during the antibiotic resistance era. With their high specificity, they are being widely used in various applications: medicine, food industry, agriculture, animal farms, biotechnology, diagnosis, etc. Many techniques have been designed by different researchers for phage isolation, purification, and amplification, each of which has strengths and weaknesses. However, all aim at having a reasonably pure phage sample that can be further characterized. Phages can be characterized based on their physiological, morphological or inactivation tests. Microscopy, in particular, has opened a wide gate not only for visualizing phage morphological structure, but also for monitoring biochemistry and behavior. Meanwhile, computational analysis of phage genomes provides more details about phage history, lifestyle, and potential for toxigenic or lysogenic conversion, which translate to safety in biocontrol and phage therapy applications. This review summarizes phage application pipelines at different levels and addresses specific restrictions and knowledge gaps in the field. Recently developed computational approaches, which are used in phage genome analysis, are critically assessed. We hope that this assessment provides researchers with useful insights for selection of suitable approaches for Phage-related research aims and applications.

scholarly journals Oviposition Preferences and Behavior of Wild-Caught and Laboratory-Reared Coconut Rhinoceros Beetle, Oryctes rhinoceros (Coleoptera: Scarabaeidae), in Relation to Substrate Particle Size

Insects ◽  
2018 ◽  
Vol 9 (4) ◽  
pp. 141 ◽  
Author(s):  
Megan Manley ◽  
Michael Melzer ◽  
Helen Spafford
Keyword(s):  
Particle Size ◽  
Oviposition Behavior ◽  
Particle Sizes ◽  
Breeding Sites ◽  
Oryctes Rhinoceros ◽  
Rhinoceros Beetle ◽  
Oviposition Preferences ◽  
Choice Tests ◽  
And Behavior ◽  
Substrate Particle

The coconut rhinoceros beetle (CRB), Oryctes rhinoceros (L.) (Coleoptera: Scarabaeidae), has become one of the most important coconut and oil palm pests. This species was detected attacking coconut palms on Oʻahu, Hawaiʻi in December 2013, and an eradication program was initiated. One of the major challenges for eradication has been the identification of new breeding sites. Information on the factors influencing oviposition is needed to aid in finding sites likely to host the immature stages of this insect. In this study, a series of choice tests were conducted to assess the oviposition preferences of both laboratory-reared and wild-caught CRB. Mated females, of both lab-reared and wild-caught beetles, were offered for oviposition a choice between sand and two mulch substrates, one with small and one with large particle sizes. Both types of CRB laid eggs preferentially in substrate of small particle size rather than large and none laid eggs in sand. Lab-reared and wild-caught CRB differed in their oviposition behavior and size. These results can be used to aid in the identification of breeding sites for management programs and eradication efforts.

The sponge genetree server—providing a phylogenetic backbone for poriferan evolutionary studies

Zootaxa ◽  
2008 ◽  
Vol 1939 (1) ◽  
pp. 58-60 ◽  
Author(s):  
DIRK ERPENBECK ◽  
OLIVER VOIGT ◽  
MEHMET GÜLTAS ◽  
GERT WÖRHEIDE
Keyword(s):  
Phylogenetic Relationships ◽  
Population Studies ◽  
Phylogenetic Signal ◽  
Careful Evaluation ◽  
Evolutionary Studies ◽  
Individual Project ◽  
Dna Sequence Markers ◽  
Species Assignment ◽  
Definition Of ◽  
Selection Of

Unravelling the phylogenetic relationships of sponges (Phylum Porifera) is an important as well as challenging task. It helps the understanding of character evolution among early branching metazoans but also aids in bioprospecting for valuable bioactive sponge compounds. However, the phylogenetic relationships among Porifera are largely unsolved, because the simple poriferan bauplan frequently prevents unambiguous taxonomic species assignment and a clear definition of morphological synapomorphies is difficult (see e.g. Boury-Esnault 2006). DNA sequence markers are frequently employed to overcome morphological shortcomings in phylogeny (e.g. Kelly Borges et al. 1991) and taxonomy (e.g. DNA barcoding, see Wörheide & Erpenbeck 2007). However, some DNA markers suffer from insufficient phylogenetic signal (see e.g. Duran et al. 2004 and Wörheide 2006 on CO1 in population studies) and unequal evolutionary rates among taxa (see e.g. Erpenbeck et al. 2004 on 28S in Haplosclerida). Therefore, a careful evaluation and selection of molecular markers for each individual project is required.

scholarly journals Characterization of marginal zone B cell precursors

2005 ◽  
Vol 202 (9) ◽  
pp. 1225-1234 ◽  
Author(s):  
Bhaskar Srivastava ◽  
William J. Quinn ◽  
Kristin Hazard ◽  
Jan Erikson ◽  
David Allman
Keyword(s):  
B Cells ◽  
B Cell ◽  
Marginal Zone ◽  
Environmental Cues ◽  
Developmental Potential ◽  
B Cell Maturation ◽  
B Cell Precursors ◽  
Follicular B Cells ◽  
Selection Of

Selection of recently formed B cells into the follicular or marginal zone (MZ) compartments is proposed to occur by way of proliferative intermediates expressing high levels of CD21/35 and CD23. However, we show that CD21/35high CD23+ splenocytes are not enriched for proliferative cells, and do not contribute substantially to the generation of follicular B cells. Instead, ontogenic relationships, steady-state labeling kinetics, and adoptive transfer experiments suggest that CD21/35high CD23+ splenocytes serve primarily as precursors for MZ B cells, although their developmental potential seems to be broader and is influenced by environmental cues that are associated with lymphopenia. Furthermore, CD21/35high CD23+ splenocytes share several key functional characteristics with MZ B cells, including their capacity to trap T-independent antigen and a heightened proliferative response to LPS. These observations challenge previous models of peripheral B cell maturation, and suggest that MZ B cells develop by way of CD21/35high CD23+ intermediates.

Cultivable microbiota of Lithobates catesbeianus and advances in the selection of lactic acid bacteria as biological control agents in raniculture

2012 ◽  
Vol 93 (3) ◽  
pp. 1160-1167 ◽  
Author(s):  
Gabriela Montel Mendoza ◽  
Sergio E. Pasteris ◽  
Cesar E. Ale ◽  
María C. Otero ◽  
Marta I. Bühler ◽  
...  
Keyword(s):  
Biological Control ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Biological Control Agents ◽  
Lithobates Catesbeianus ◽  
Selection Of
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