Families on the spot: sexual signals influence parent–offspring interactions

In 1950, Tinbergen described the elicitation of offspring begging by the red spot on the bill of parent gulls, and this became a model system for behavioural studies. Current knowledge on colour traits suggests they can act as sexual signals revealing individual quality. However, sexual signals have never been studied simultaneously in relationship to parent–offspring and sexual conflicts. We manipulated the red-spot size in one member of yellow-legged gull pairs and observed their partners' feeding efforts in relationship to offspring begging. In the enlarged-spot group, partners doubled their effort compared with the other groups. Furthermore, in the reduced-spot group, partners provided food in relationship to offspring begging, contrasting with the fixed effort of the partners of enlarged-spot gulls. Manipulated gulls, independently of treatment, provided food in relationship to chicks begging only when the partner's investment was low, and performed a fixed effort when the partner's contribution was high. Results demonstrate that the red spot in yellow-legged gulls functions as a sexual signal and indicate that parental rules are plastic, depending on the information on offer. Previous evidence and this study indicate that this signal is used by all family members to adjust decision rules. The incorporation of sexual signals in parent–offspring interactions can be crucial in understanding intra-familial conflicts.

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The pseudomalachite-ludjibaite-reichenbachite conundrum: OD description

The Canadian Mineralogist ◽

10.3749/canmin.1900016 ◽

2019 ◽

Vol 57 (5) ◽

pp. 571-581

Author(s):

Emil Makovicky

Keyword(s):

Crystal Structures ◽

Current Knowledge ◽

The Other ◽

Crystal Chemical ◽

Layer System ◽

Coordination Polyhedra

Abstract Crystal structures of the three polymorphs of Cu5(PO4)2(OH)4, namely pseudomalachite, ludjibaite, and reichenbachite, can be described as being composed of rods perpendicular to their crystal-chemical layering. Two different sorts of rods can be defined. Type 1 rods share rows of Cu coordination polyhedra, forming a series of slabs. Slab boundaries and slab interiors represent alternating geometric OD layers of two kinds, with layer symmetries close to P21/m and , which make up two different stacking schemes of geometric OD layers in the structures of ludjibaite and pseudomalachite. Such OD layers, however, are not developed in reichenbachite. Type 2 rods are defined as having columns of PO4 tetrahedra in the corners of the rods. In the Type 2 slabs composed of these rods, geometric Pg OD layers of glide-arrayed tetrahedra alternate with more complex OD layers; in ludjibaite this system of layers is oriented diagonally with respect to the Type 1 OD layer system. Two different OD stackings of Type 2 OD layers form the ludjibaite and reichenbachite structures but not that of pseudomalachite. Thus, ludjibaite might form disordered intergrowths with either of the other two members of the triplet but reichenbachite and pseudomalachite should not form oriented intergrowths. Current knowledge concerning formation of the three polymorphs is considered.

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Research on Plants for the Understanding of Diseases of Nuclear and Mitochondrial Origin

Journal of Biomedicine and Biotechnology ◽

10.1155/2012/836196 ◽

2012 ◽

Vol 2012 ◽

pp. 1-12 ◽

Cited By ~ 5

Author(s):

Claudia P. Spampinato ◽

Diego F. Gomez-Casati

Keyword(s):

Current Knowledge ◽

Model System ◽

Human Diseases ◽

Model Organisms ◽

Human Cell Lines ◽

Molecular Defects ◽

Human Genes ◽

Clinical Disorders ◽

Mitochondrial Origin ◽

Experimental Findings

Different model organisms, such asEscherichia coli,Saccharomyces cerevisiae,Caenorhabditis elegans,Drosophila melanogaster, mouse, cultured human cell lines, among others, were used to study the mechanisms of several human diseases. Since human genes and proteins have been structurally and functionally conserved in plant organisms, the use of plants, especiallyArabidopsis thaliana, as a model system to relate molecular defects to clinical disorders has recently increased. Here, we briefly review our current knowledge of human diseases of nuclear and mitochondrial origin and summarize the experimental findings of plant homologs implicated in each process.

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Selective Cytotoxicity of Carboxypeptidase-activated Methotrexate ex-Peptides

Pteridines ◽

10.1515/pteridines.1989.1.1.65 ◽

1989 ◽

Vol 1 (1) ◽

pp. 65-69 ◽

Cited By ~ 6

Author(s):

Karin S. Vitols ◽

Yolanda D. Montejano ◽

Ulrike Kuefner ◽

F. M. Huennekens

Keyword(s):

Monoclonal Antibodies ◽

Amino Acid ◽

Suspension Culture ◽

Parent Drug ◽

Model System ◽

The Other ◽

Carboxypeptidase A ◽

Selective Cytotoxicity ◽

Cell Kill ◽

Semi Solid

Summary Methotrexate ex-pep tides (derivatives in which an amino acid is linked covalently to the ex-carboxyl of the glutamate residue on the parent drug) can be hydrolyzed by specific carboxypeptidases to yield free Methotrexate (MTX) and the corresponding amino acid. Studies with L12l0 cells in suspension culture have shown that the MTX pep tides can serve as "pro-drugs": Because of their inability to be taken up by cells, they are relatively non-toxic. When co-administered with appropriate carboxypeptidases, however, they become equitoxic with MTX. In the present investigation, the potential of the MTX-ala/carboxypeptidase A combination for providing regional cytotoxicity was demonstrated in a model system involving L12l0 cells propagated in semi-solid agarose. When cells and one of the components (MTX peptide or carboxypeptidase) were distributed uniformly throughout the agarose, and the other component was immobilized at the center, a discrete zone of cell kill radiated from the fixed component. These results suggest the possibility of developing a new mode of cancer chemotherapy involving circulating MTX peptides in conjunction with carboxypeptidases linked covalently to tumor-targeted monoclonal antibodies.

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Restorative justice and victims: Not a self-evident relationship

Temida ◽

10.2298/tem0601011p ◽

2006 ◽

Vol 9 (1) ◽

pp. 11-20 ◽

Cited By ~ 2

Author(s):

Antony Pemberton ◽

Frans Winkel ◽

Mark Groenhuijsen

Keyword(s):

Social Psychology ◽

Theoretical Model ◽

Criminal Justice ◽

Restorative Justice ◽

Traumatic Stress ◽

Current Knowledge ◽

The Other ◽

European Forum ◽

Victim Services ◽

Evident Relationship

The two most prominent developments in criminal justice in the last twenty to thirty years are the rise of restorative justice and the recognition and improvement of the position of the victim. The first part of the paper discusses a theoretical model for victims within restorative justice that the researchers at the InterVICT research institute authors of this paper) are developing at this moment. This model incorporates current knowledge from social psychology and studies surrounding traumatic stress and provides a number of hypotheses that will be subsequently evaluated in practice with participants in restorative justice procedures. On the other hand, international legal protocols for restorative justice also lack a consistent victim-oriented perspective. To this end the European Forum for Victim Services has recently published a statement concerning the position of the victim within mediation. The second part of the paper addresses the central issues in this statement. Taken together the paper moves beyond criticism of restorative justice, as it hopes to redirect theory and implementation of restorative justice toward a stronger victim-orientation.

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Victims’ relation towards the offence and victim-offender mediation

Temida ◽

10.2298/tem1401097h ◽

2014 ◽

Vol 17 (1) ◽

pp. 97-112

Author(s):

Jasna Hrncic ◽

Tatjana Rajic

Keyword(s):

Current Knowledge ◽

Paper Analyse ◽

The Other ◽

Check List ◽

Self Confidence ◽

Assessment Visit ◽

Almost All

The paper analyse relation of victims toward the offence and their readiness for victim-offender mediation (VOM). Aims were analysis of feelings, behaviours and needs of victims regarding the offence, as well as and analysis of readiness of victims for VOM. 17 mediators assessed 41 victims and 42 offenders, participants of 41 VOM by Assessment Visit Check List (Quill, Wynne, 1993). Victims showed strong feelings of bitterness, anger and grievance more frequently than offenders, while offenders showed feeling of guilt more frequently than victims. Victims had higher defensive attitude and self-confidence then offenders. Almost all victims and offenders needed reparation and agreement with the other party. Most of them wanted to know more about the other party in conflict and were opened to contacts with him. The results were discussed in relation to current knowledge.

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Variable and sub-optimal responses to a choice problem are a persistent default mode

10.31234/osf.io/p37tg ◽

2019 ◽

Author(s):

Amelia R. Hunt ◽

Warren James ◽

Josephine Reuther ◽

Melissa Spilioti ◽

Eleanor Mackay ◽

...

Keyword(s):

Optimal Strategy ◽

Decision Rules ◽

Optimal Solution ◽

The Other ◽

Rational Decision ◽

Choice Problem ◽

Default Mode ◽

Potential Benefits ◽

Simple Logic ◽

Simple Decision Rule

Here we report persistent choice variability in the presence of a simple decision rule. Two analogous choice problems are presented, both of which involve making decisions about how to prioritize goals. In one version, participants choose a place to stand to throw a beanbag into one of two hoops. In the other, they must choose a place to fixate to detect a target that could appear in one of two boxes. In both cases, participants do not know which of the locations will be the target when they make their choice. The optimal solution to both problems follows the same, simple logic: when targets are close together, standing at/fixating the midpoint is the best choice. When the targets are far apart, accuracy from the midpoint falls, and standing/fixating close to one potential target achieves better accuracy. People do not follow, or even approach, this optimal strategy, despite substantial potential benefits for performance. Two interventions were introduced to try and shift participants from sub-optimal, variable responses to following a fixed, rational rule. First, we put participants into circumstances in which the solution was obvious. After participants correctly solved the problem there, we immediately presented the slightly-less-obvious context. Second, we guided participants to make choices that followed an optimal strategy, and then removed the guidance and let them freely choose. Following both of these interventions, participants immediately returned to a variable, sub-optimal pattern of responding. The results show that while constructing and implementing rational decision rules is possible, making variable responses to choice problems is a strong and persistent default mode. Borrowing concepts from classic animal learning studies, we suggest this default may persist because choice variability can provide opportunities for reinforcement learning.

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G6PD deficiency is a common genetic trait that can protect heterozygotes from dying from malaria

10.31219/osf.io/g2kza ◽

2021 ◽

Author(s):

Moataz Dowaidar

Keyword(s):

G6pd Deficiency ◽

Model System ◽

The Other ◽

Medical Emergency ◽

Red Cell ◽

Biochemical Genetics ◽

Genetic Trait ◽

Common Cause ◽

Fava Bean ◽

Deficient Child

G6PD deficiency is a common genetic trait that can protect heterozygotes from dying from malaria (save in the extremely tiny fraction of individuals who have CNSHA). AHA in a G6PD-deficient child or adult, on the other hand, is a medical emergency that, if not treated promptly and properly, can be fatal. Fava bean consumption is the most common cause of AHA: favism is seen in at least 35 countries, with thousands of cases reported each year. Both primaquine and rasburicase have been linked to iatrogenic deaths in the same and other nations, and these deaths may have been averted. Population screening and health education, as well as the cultivation of fava bean types with nil or low vicine and convicine levels, can help to prevent fascism. G6PD biology is eminently interdisciplinary, having served as a model system in biochemical genetics and in understanding how the red cell responds to oxidative stress; a tool for studying X-chromosome inactivation (human development's most spectacular epigenetic event); a tool for studying clonal populations for years; and a pioneer in the molecular genetics of enzymopathies.

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WATER FLOWS AROUND THE COMB PLATES OF THE CTENOPHORE PLEUROBRACHIA PLOTTED BY COMPUTER: A MODEL SYSTEM FOR STUDYING PROPULSION BY ANTIPLECTIC METACHRONISM

Journal of Experimental Biology ◽

10.1242/jeb.177.1.113 ◽

1993 ◽

Vol 177 (1) ◽

pp. 113-128 ◽

Cited By ~ 1

Author(s):

D. Barlow ◽

M. A. Sleigh ◽

R. J. White

Keyword(s):

Computer Program ◽

Water Flow ◽

High Speed ◽

Beat Frequency ◽

Longitudinal Axis ◽

Model System ◽

The Other ◽

Contour Maps ◽

Water Flows ◽

Pleurobrachia Pileus

Patterns of water flow around steadily beating comb plates of Pleurobrachia pileus were tracked using suspended plastic beads. The positions of the beads and the comb plates in the plane of the central longitudinal axis of the comb row were digitised from high-speed cine films covering several beat cycles. All of the data from each sequence were combined using a computer program which integrated them into a standard cycle, and the resulting data were plotted by a second computer program to produce charts for different stages in the beat cycle showing the flow velocity at a grid of points. On these charts, contour maps were drawn to indicate the speed and direction of the water flow. Water is drawn towards each comb row from ahead and from the sides and accelerates strongly backwards in a fairly narrow stream which joins those from the other seven comb rows at the rear of the animal. At a beat frequency of 10 Hz the comb plates move with a tip speed of up to 70 mm s-1 in their effective stroke; they have an estimated Reynolds number of 9 in this stroke. Changes in inter- plate volume between adjacent antiplectically coordinated plates are very important in propulsion, particularly near the end of the effective stroke when pairs of adjacent plates close together and cause the high-speed water from around the ciliary tips to be shed into the overlying stream as a series of jets at speeds of 50 mm s-1 or more. The antiplectic coordination of the comb plates makes a major contribution to the efficiency of propulsion.

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A new species of Aethiopella Handschin, 1942 (Collembola, Poduromorpha, Neanuridae) from Neotropical Region, with comments on the genus

Zootaxa ◽

10.11646/zootaxa.4629.1.3 ◽

2019 ◽

Vol 4629 (1) ◽

pp. 39-50 ◽

Cited By ~ 1

Author(s):

RAIANE VITAL DA PAZ ◽

GABRIEL COSTA QUEIROZ ◽

BRUNO CAVALCANTE BELLINI

Keyword(s):

New Species ◽

Current Knowledge ◽

Antennal Segment ◽

Neotropical Region ◽

The Other ◽

Wide Range ◽

Morphological Differences ◽

A New Species

Aethiopella Handschin, 1942 as other Pseudachorutinae (Neanuridae) presents a diagnosis with overlapping characters when compared to other similar genera, especially Halachorutes Arlé, 1966, Ceratrimeria Börner, 1906 and Pseudachorutes Tullberg, 1871. This condition, combined to several gaps on the knowledge of described species and a wide range of morphological differences within the genus, reinforces the need of its revision, since it can be an artificial group. In spite of that, a new species, Aethiopella ricardoi sp. nov., is described and illustrated. It resembles the other five Neotropical taxa of Aethiopella but is unique by the combination of fourth antennal segment with trilobed apical bulb and 7 dorsal sensilla, lack of dorsolateral S-microchaeta (ms); postantennal organ with 13–19 vesicles; mandibles with 7–8 teeth; maxillae apically hooked; and tibiotarsi I–III with 19/19/18 chaetae, respectively, with M chaeta slightly basally displaced. We also present an updated diagnosis of Aethiopella based on current knowledge of Pseudachorutinae, a table comparing all species, a key to Neotropical taxa and remarks on the genus.

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Fidelity in Archaeal Information Processing

Archaea ◽

10.1155/2010/960298 ◽

2010 ◽

Vol 2010 ◽

pp. 1-15 ◽

Cited By ~ 2

Author(s):

Bart de Koning ◽

Fabian Blombach ◽

Stan J. J. Brouns ◽

John van der Oost

Keyword(s):

Gene Expression ◽

Quality Control ◽

Information Processing ◽

Genome Size ◽

Genetic Information ◽

Important Determinant ◽

Current Knowledge ◽

The Other ◽

Living Systems ◽

Evolution Of Life

A key element during the flow of genetic information in living systems is fidelity. The accuracy of DNA replication influences the genome size as well as the rate of genome evolution. The large amount of energy invested in gene expression implies that fidelity plays a major role in fitness. On the other hand, an increase in fidelity generally coincides with a decrease in velocity. Hence, an important determinant of the evolution of life has been the establishment of a delicate balance between fidelity and variability. This paper reviews the current knowledge on quality control in archaeal information processing. While the majority of these processes are homologous in Archaea, Bacteria, and Eukaryotes, examples are provided of nonorthologous factors and processes operating in the archaeal domain. In some instances, evidence for the existence of certain fidelity mechanisms has been provided, but the factors involved still remain to be identified.

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