Search results for "spring"
showing 10 items of 600 documents
How amniotic fluid shapes early odor-guided responses to colostrum and milk (and more)
2016
Revue; Among the multiple transitions that characterize mammalian development, birth certainly is the most abrupt and spectacular. It is also the most challenging for newborns when one considers their high mortality rates in any mammalian species. Although evolution has selected newborn organisms that possess the physiological and behavioral keys leading to adapt to this harsh psychobiological challenge, their capabilities cannot be considered separately from the maternal organism and the environment she creates. Mammalian females provide indeed passive (physiological) and/or active (behavioral) assistance to complement and boost their offspring’s capacities. One notable strategy of mammali…
La Red Trampolín: Multinacionales en Latinoamérica
2014
El tema de la casa matriz regional cuenta con cierto nivel de investigación con respecto a las condiciones que inciden en la evolución de una filial, hasta transformarse en casa matriz regional (Bouquet y Birkinshaw, 2008). Dentro de este mismo orden de ideas, ha surgido el fenómeno de la regionalización debido a la creciente necesidad de atender mercados e industrias más maduras (Adler y Hashai, 2007). A pesar de las aproximaciones realizadas al tema, existe una reorganización a nivel regional en diversos contextos que debe ser estudiada a profundidad (Rugman y Verbeke, 2005 y Arregle, Beamish y Hébert, 2009). Esta investigación tiene como objetivo profundizar en los procesos de regionaliz…
Genetic and potential non-genetic benefits increase offspring fitness of polyandrous females in non- resource based mating system
2010
Background: The adaptive significance of female polyandry is currently under considerable debate. In non-resource based mating systems, indirect, i.e. genetic benefits have been proposed to be responsible for the fitness gain from polyandry. We studied the benefits of polyandry in the Arctic charr (Salvelinus alpinus) using an experimental design in which the material investments by the sires and maternal environmental effects were controlled. Results: Embryonic mortality showed a strong paternal genetic component, and it was lower in polyandrously fertilized offspring (sperm competition of two males) than in monandrous fertilizations. We also found that high sperm velocity was associated w…
Critical Exploration of Flexible Delivery
2020
This work-in-progress research article presents an introductory qualitative study on students' perceptions of a flexibly delivered, modular computer science course. Many contemporary approaches to education rely in various ways on flexible delivery of course content. This is often done to capitalize on modern technology and the web, and to put the student ‘in the center.' However, it is becoming manifest that these approaches may challenge both the students and the equity between them, making it important to understand the effects of flexible delivery in terms of the students. In the voice of our students, flexible delivery was seen as a largely positive approach, reducing stress, promoting…
Motor Transitions' Peculiarity of Heterozygous DAT Rats When Offspring of an Unconventional KOxWT Mating.
2020
Abstract Causal factors of psychiatric diseases are unclear, due to gene × environment interactions. Evaluation of consequences, after a dopamine-transporter (DAT) gene knock-out (DAT-KO), has enhanced our understanding into the pathological dynamics of several brain disorders, such as Attention-Deficit/Hyperactivity and Bipolar-Affective disorders. Recently, our attention has shifted to DAT hypo-functional (heterozygous, HET) rodents: HET dams display less maternal care and HET females display marked hypo-locomotion if cared by HET dams (Mariano et al., 2019). We assessed phenotypes of male DAT-heterozygous rats as a function of their parents: we compared “maternal” origin (MAT-HET, obtain…
When earwig mothers do not care to share: Parent–offspring competition and the evolution of family life
2017
Kin competition often reduces – and sometimes entirely negates – the benefits of cooperation among family members. Surprisingly, the impact of kin competition on the fitness effects of family life only received close scrutiny in studies on sibling rivalry, whereas the possibility of parent–offspring competition has attracted much less attention. As a consequence, it remains unclear whether and how parent–offspring competition could have affected the early evolution of parental care and family life. Here, we examined the occurrence and consequences of parent–offspring competition over food access in the European earwig Forficula auricularia, an insect with facultative family life reminiscent…
Environmental Enrichment During Adolescence Mitigates Cognitive Deficits and Alcohol Vulnerability due to Continuous and Intermittent Perinatal Alcoh…
2020
Perinatal alcohol exposure affects ontogenic neurodevelopment, causing physical and functional long-term abnormalities with limited treatment options. This study investigated long-term consequences of continuous and intermittent maternal alcohol drinking on behavioral readouts of cognitive function and alcohol vulnerability in the offspring. The effects of environmental enrichment (EE) during adolescence were also evaluated. Female rats underwent continuous alcohol drinking (CAD)—or intermittent alcohol drinking paradigm (IAD), along pregestation, gestation, and lactation periods—equivalent to the whole gestational period in humans. Male offspring were reared in standard conditions or EE un…
Intergenerational Effect of Early Life Exposure to Permethrin: Changes in Global DNA Methylation and in Nurr1 Gene Expression
2015
Environmental exposure to pesticides during the early stages of development represents an important risk factor for the onset of neurodegenerative diseases in adult age. Neonatal exposure to Permethrin (PERM), a member of the family of synthetic pyrethroids, can induce a Parkinson-like disease and cause some alterations in striatum of rats, involving both genetic and epigenetic pathways. Through gene expression analysis and global DNA methylation assessment in both PERM-treated parents and their untreated offspring, we investigated on the prospective intergenerational effect of this pesticide. Thirty-three percent of progeny presents the same Nurr1 alteration as rats exposed to permethrin i…
Evolutionary trade-offs in a small mammal : a quantitative genetics approach
2017
Limited resources force individuals to trade-off between life-history traits. A vast diversity of life-history strategies, which optimally combine life history traits, can be found. Knowledge of the genetic basis of this phenotypic variation is key to understanding evolutionary processes. I approached life-history evolution by estimating quantitative genetic parameters for a set of life-history traits in the bank vole (Myodes glareolus). The work is based on a laboratory-kept colony subjected to two-way selection for litter size (High- (H) and Low- (L) lines). Costs of the created reproductive strategies were observed in natural conditions. Selection increased the difference in litter size …
Informācijas sistēma repetitoru un konsultāciju pieteikumu uzskaitei
2021
Kvalifikācijas darbā ir aprakstīta sistēma, kas paredzēta repetitoru konsultāciju organizēšanai. Sistēmas lietotāji ir skolēni, repetitori un administratori. Sistēma piedāvās iespēju reģistrētiem lietotājiem elektroniski pierakstīties uz konsultāciju pie repetitora, aplūkot savu pierakstu vēsturi un atstāt atsauksmi par repetitoru. Lietotāji ar repetitora lomu varēs izvēlēties mācību priekšmetus, kurus viņi vēlētos pasniegt, un izveidot konsultācijas, norādot atrašanās vietu un laiku. Repetitors varēs pārskatīt savas konsultācijas, lietotāju komentārus un redzēt to lietotāju kontaktinformāciju, kas pierakstījušies pie konkrētā repetitora. Administratori sistēmā varēs piešķirt lietotājiem re…