Miracle-dz/UniFAR-FTUs huggingface dataset:
Dazl regulates mouse embryonic germ cell development

In the mouse, germ cells can undergo differentiation to become either oocytes or spermatozoa in response to sex of their gonadal environment. The nature of the germ cell-intrinsic aspects of this signaling have not been well studied. The earliest known sex-specific difference in germ cells is the initiation of meiosis in female, but not male, embryonic germ cells. Experiments were performed showing that germ cells of both sexes transit through a state, the meiosis competent germ cell, that is required for initiation of meiosis. Acquisition of this state requires the function of the germ cellspecific RNA binding protein DAZL. The sufficiency for the absence of meiosis to drive male germ cell differentiation was then tested by examining non-meiotic XX germ cells in the Dazl-deficient ovary. These cells did not exhibit male differentiation indicating that the absence of meiosis is not sufficient for male differentiation. XX Dazl-deficient germ cells also failed to exhibit normal female differentiation. In addition, XY Dazl-deficient germ cells do not display characteristics of either male or female germ cells. Taken together, these results indicate that germ cells must first undergo a sex non-specific differentiation step prior to acquiring sexual fate.
The role of Cdc7 and cyclin-dependent kinases in DNA replication and S phase

The cell cycle is a highly orchestrated developmental process that eventually leads to the reproduction of a cell. In metazoans, it is driven by the successive activation of cyclin-dependent kinases (Cdk) and proper coordination of cell cycle transitions and processes ensure genomic stability. DNA replication takes place during S phase to faithfully duplicate a cellʼs genetic material. In eukaryotes, S phase onset involves the initiation of numerous licensed replication origins across the genome and requires the activities of two protein kinases, S phase-Cdk and Cdc7. In this thesis, I present work relating to the role of the S phase-promoting kinases in DNA replication and S phase regulation. Using the cell-free system of Xenopus egg extracts, a small molecule inhibitor of Cdc7 was characterised. PHA-767491 was then used to demonstrate that Cdc7 executes its activity early in S phase before the Cdk-dependent step. Cdc7 is not rate limiting for the progression of the replication timing programme once its essential function has been executed, unlike S-Cdk whose activity is required throughout S phase. Protein Phosphatase 1 (PP1) was identified as a modulator of Cdc7 activity in egg extracts, which rapidly reverses Cdc7-dependent phosphorylation of chromatin-bound Mcm4 and likely functionally lowers Cdc7 activity during an etoposide-induced checkpoint response. This provides a novel mechanism for regulating Cdc7 by counteracting its activity on essential replication substrates in the event of replicative stress. In the second part of the thesis, the design strategy for generating a Cdc7-conditional knockout mouse (cko) is outlined and results from the screen for a transgenic founder are presented. A Cdc7-cko mouse will be a valuable tool to further dissect Cdc7 function and regulation in mammalian cells. In the final section, S phase entry and progression in mouse embryonic fibroblasts lacking both Cdk1 and Cdk2 was examined. Contrary to expectations, Cdk1/Cdk2 double knockout cells can enter S phase in the absence of detectable S phase-Cdk activity. S phase progression, however, was inefficient. Cdc6 and cyclin E1 proteins were found to accumulate in high levels in these cells although the exact function(s) and mechanism(s) for these observations remain to be discovered. With this work, I hope to provide additional insight into the roles and regulation of S phase kinases in eukaryotic DNA replication.
Teacher Candidates’ Expectations: Equity Education, Critical Literacy, and Indigenous Students’ Epistemologies

Culturally responsive teachers respond positively to students’ cultural norms and traditions by creating inviting and meaningful learning opportunities that distinguish between Indigenous and western perspectives; however, in classrooms where teachers’ understanding of Indigenous epistemologies and worldviews are not necessarily sufficiently represented, Indigenous students not only often feel marginalized and isolated but disengaged from Eurocentric curriculum and texts that fail to incorporate their histories and traditions. This study focuses on the expectations and perceptions of teacher candidates (prior to their field practicum experiences in classrooms) related specifically to equity education, reflective practice, and critical literacy. The mixed-methods study examines prospective teachers’ perceptions of issues related to Indigenous students, and how public education policy and practice manifests in classrooms. The findings suggest that prospective teachers are doubtful of the fact that Indigenous voices are being presented competently to enhance student learning and foster Indigenous student identity. Moreover, prospective teachers anticipate a fundamental disconnect between the Ontario policy outcomes related to Indigenous education and the practice of teachers in school.
Morphogenèse de compartiments membranaires : formation de l'autophagosome chez les plantes

L'autophagie est un processus permettant la degradation de constituants cytosoliques dans un compartiment lytique, par leur sequestration au sein d'une vesicule a double membrane : l'autophagosome. L'autophagie est, avec la voie ubiquitine-proteasome, l'une des deux grandes voies de degradation presente de maniere fortement conservee chez les cellules eucaryotes. Presente a un niveau basal, elle peut etre stimulee afin de permettre la remobilisation de ressources cellulaires, ou d'assurer des fonctions cytoprotectrices et de detoxification. La formation d'autophagosomes traduit alors la capacite du systeme endomembranaire a s'adapter aux besoins cellulaires. Cependant, la mecanique membranaire et moleculaire de ce phenomene reste mal comprise. L'objectif de ce travail de these etait de mieux comprendre la formation de ce compartiment dans la cellule vegetale. Pour cela, nous avons tout d'abord mis au point les conditions propices a l'etude de l'autophagie dans la racine d’Arabidopsis thaliana, puis nous avons entrepris l'identification de marqueurs des etapes de formation de l'autophagosome. L'etude par imagerie en temps reel et 3D de la proteine ATG5, impliquee dans l’expansion membranaire, nous a permis de mettre en evidence son recrutement transitoire sur un domaine particulier de l'autophagosome en formation, son ouverture. De plus, l'etude de differents acteurs du systeme endomembranaire, nous a permis de mettre en evidence et de caracteriser l'implication du reticulum endoplasmique et de ATG9, pour aboutir a un modele de la formation de l'autophagosome chez les plantes.
Review of the Crown-of-thorns Starfish Research Committee (COTSREC) Program

Scientists and managers often view issues from different perspectives. Scientists as a group have traditionally wished to learn more about an issue for the sake of learning, for the sake of testing a hypothesis, for the sake of furthering their careers or for a combination of these reasons. While managers are also curiosity driven, they are usually required to focus their curiosity on those aspects of matters which are vital to the solution of management problems. From the manager's perspective, the fundamental question to be answered about the COTS phenomenon is whether or not it has been grossly affected by human activity. On the basis of the answer to that question, the manager will determine his response, particularly whether or not to interfere in the 'natural' system or to refrain from interference. The logic of this position is discussed. The Authority's policy on controlling COTS is not to interfere on a large scale unless it can be shown that outbreaks are caused or exacerbated by human activity. However local controls are initiated to protect sites of particular value to tourism or science. Every scientific review of this matter has supported our policy. Many people adopt one of two fundamentally different explanations for why crown-of-thorns populations suddenly increase dramatically. One is that the phenomenon is entirely 'natural'. That is, it is not affected by human activity. The other is that it is entirely human-induced. Of course, bearing in mind the pervasive effect that human activity is having on the world's biosphere, it is quite likely that the truth is a mixture of these two views, that is, that crown-of-thorns infestations are affected to some degree by human activity. We don't however, know whether this is so, and if it is, whether human activity is contributing to the intensity, frequency or extent of the phenomenon positively or negatively. The Authority recognises that long-term protection of the Reef ecosystem is the primary reason for the existence of the Authority and for everything that we do. Therefore we approach the crown-of-thorns issue from the perspective of risk. We know that the animal is a natural inhabitant of the Reef and that is has been around for millennia. We know, therefore, that the Reef as we know and cherish it has developed in the presence of the starfish. That is not to say that there have always been recurrent population explosions, but there may have been. The primary question is: should we undertake widespread and massive destruction of crown-of-thorns starfish whenever there is a primary outbreak? What are the risks and benefits of non-interference? Clearly, an immediate benefit is the saving of an enormous amount of money. Experience has shown that it costs up to S35 per starfish to kill large
Theropithecus: Theropithecus darti from the Hadar Formation, Ethiopia

Summary The well-preserved sample of specimens of Theropithecus darti (Broom & Jensen, 1946) from the Hadar Formation of northeastern Ethiopia makes significant contributions to our understanding of the early evolution of the T. oswaldi lineage and to the initial radiation of the genus Theropithecus . The Hadar specimens are the first of the species to be associated with radiometrically dated sediments. The age of these sediments indicates that the specimens are between 3.4 and 2.9 Ma old and are, thus, the oldest of the species yet described. The well-preserved adult male cranial and mandibular specimens allow, for the first time, description of the adult male skull of the species. Characteristics of Hadar males, as well as females, confirm the close relationship of T. darti to T. oswaldi proposed by others based on specimens from Makapansgat in South Africa. The Hadar specimens share with those from Makapansgat a small suite of primitive characters that are used to differentiate the two species and, in conjunction with the derived characters shared with T. oswaldi , indicate an ancestor-descendant relationship between them. The larger size of the specimens from Makapansgat and the occurrence of more derived dental and mandibular characters suggest that they are younger in age than those from Hadar, as does evidence from suid biostratigraphy. The occurrence of T. darti in the middle Pliocene of East Africa and the late Pliocene of South Africa indicates that the species was probably widely distributed in sub-Saharan Africa during later Pliocene times. […]
DNA Methylation Analysis Methods for Cancer Research

DNA methylation is an important epigenetic modification mechanism, interacting with histone modification, changing the structure of chromatin and regulating gene expression. Meanwhile, there is a close relationship with cell proliferation, aging, cancer and other life phenomena. DNA methylation includes DNA undermethylation and local high CpG island methylation on the whole genome. By the help of DNA methyltransferases (DNMTs), DNA methylation can be completed. With the development of further research on epigenetics and DNA methylation, genomic methylation detection technology has got rapid development. DNA methylation detection methods can be divided into the following categories: methylation detection, gene-specific methylation detection and searching new methylation sites. Researches on DNA methylation showed that abnormal genomic DNA methylation and tumor is closely related to the occurrence and development of DNA hypomethylation and undermethylation, which can cause abnormal expression of genes and lead to cancer. At the same time, the change of DNA methylation also provides a new way for tumor detection and treatment, which provides a new way for the treatment of cancer. In this paper, the current main analysis methods and research progress of DNA methylation were summarized and discussed preliminarily. Moreover, the relationship of abnormal DNA methylation with the occurrence and development of cancer were reviewed.
The Distribution and Influence of the Introduced Alga Colpomenia Bullosa in the Rocky Intertidal

The brown alga Colpomenia bullosa was first observed in New Zealand more than 20 years ago, yet very little is known about its current intertidal distribution or possible effects it may be having on native communities. This study addresses some of these issues. Surveys indicate little spatial variation in abundance around the Wellington region, however, the sporophytic crustose phase is restricted to pools high in the littoral zone while the gametophytic upright has a low- to sub-littoral distribution. Physiology experiments indicate that C. bullosa can tolerate a wide range of environmental conditions, but the crustose phase has a poor desiccation tolerance. A series of tranplant and competition experiments confirmed this and suggested that the crustose phase requires some level of facilitation by molluscan herbivores in order to become established. These experiments also revealed that crustose C. bullosa does not compete well against more upright macroalgal species. The effects of this introduced algae on native communities are likely to be minimal given its restricted intertidal distribution and its inability to compete against more upright species.
Investigating the evolution of diversity and complexity of Prokaryotic gene regulatory networks using in silico models

There is much debate about the evolutionary origins of diversity and many complex gene regulatory network features, such as global regulation. Using novel in silico models the evolutionary origins of complex features, heterogeneity and the role of stochastic molecular processes in gene regulatory network evolution are investigated. It is shown that: i) Repression is essential, even in constant environments, due to energetic constraints. ii) Stochastic basal gene expression forces shrinkage of genomes, whilst its absence leads to ‘bloating’. iii) Models evolved towards a biological goal have a very different network structure to nonadaptively evolved models. iv) Unstable mRNA, stable protein and rapid but robust replication times are strongly selected properties of evolved networks. v) Multiple network solutions within identical environmental conditions are observed with the presence of stochastic basal gene expression. vi) Two attractor states, one with high, and one with low stochastic basal gene expression, are observed in networks which can evolve their levels of basal expression. vii) Functional complexity of a gene regulatory network is dependent on environmental complexity. viii) Functional complexity evolves in hierarchical stages, requiring ‘core’ energy regulation mechanisms before environmental responses and adaptations for growth can be sustained and fixed. ix) Global gene regulation is strongly selected as an efficient energy regulation mechanism
Modelling the effects of temperature changes on Schistosoma mansoni transmission

Schistosomiasis is a chronic parasitic disease, estimated to affect 237 million people worldwide. It is caused by infection with Schistosoma helminths, which spend part of their lifecycles in aquatic snails. The mortality, development and fecundity rates of the parasites and their intermediate host snails are very sensitive to water temperature. The distribution and prevalence of schistosome parasites are therefore likely to be affected by climate change, however the potential effects of this have been largely neglected. Only two mathematical models of temperature and schistosome transmission in Africa have previously been developed, and neither explicitly simulated all temperature-dependent stages of the parasite and snail lifecycles. The aim of this thesis is to advance understanding of the potential effects of climate change on S. mansoni transmission, using an agent-based modelling approach. A mathematical model of water temperature, snail population dynamics and S. mansoni transmission was developed. The model was parameterised using data from Biomphalaria pfeifferi, the most widespread intermediate host species in Africa, and the dynamics of the model were explored. Infection risk was shown to be highest (above 90% of the maximum) at a constant temperature of 15-19°C. Simulating diurnal variation in temperature and/or higher cercaria and miracidium removal rates increased the optimum temperature for transmission to 16-26°C. The effect of simulating different species of intermediate host snail was also investigated. Simulating Bi. alexandrina and Bi. glabrata increased the temperature at which infection risk was highest to 19-21°C and 20-26°C respectively. The model was run using climate projections for eastern Africa. Comparisons of model output at baseline with empirical data showed that suitable temperatures are necessary but not sufficient for both schistosome transmission, and for high prevalences of schistosomiasis. All else being equal, infection risk may increase by up to 20% over most of the area over the next 20 and 50 years. Increases may be higher in Rwanda, Burundi, south-west Kenya and eastern Zambia, and schistosomiasis may become newly endemic in parts of these areas. The results for 20 years’ time are robust to changes in simulated snail habitats. There is greater uncertainty about the effects of different habitats on changes in risk in 50 years’ time.
Selection on pollen competitive ability in relation to stochastic factors influencing pollen deposition

Pollen competitive ability will only be selected if competitive situations are frequent under natural conditions. A trait must also exist that, in various instances, increases competitive ability and has a variance large enough to allow differences to persist even when affected by stochastic factors imposed by pollinator behaviour. An indication of these prerequisites is that non-random mating is common in a species. In this study on pollen competition in Viola tricolor, one donor was superior at siring ovules in 23 of 34 crosses, which indicates that nonrandom mating is common in this species. We also found maternal effects on siring ability, although they were not large enough to reverse ranking order of donors. Of two pollen traits potentially important for pollen competitive ability (i.e. tube growth rate and germination ability), only pollen tube growth rate had significant effects on siring ability. Variability in pollen tube growth rate was high enough to allow fast tube growth to be beneficial even when the effect of stochastic factors (i.e. time and place of pollen deposition) was taken into account. Taken together, these results make it plausible that sexual selection can act on pollen tube growth rate in Viola tricolor.
Investigating the link between defective DNA end-processing and human neurological disease

DNA single-strand breaks (SSB) are the most commonly occurring type of DNA damage arising in a cell and they are repaired by rapid repair pathways collectively termed single-strand break repair (SSBR). Recently several rare hereditary neurodegenerative disorders with mutations in genes associated with SSBR, spinocerebellar ataxia and axonal neuropathy-1 (SCAN1), ataxia oculomotor apraxia-1 (AOA1) and microcephaly with early onset seizures and developmental delay (MCSZ), have been discovered. A striking aspect that these disorders have in common is that they are all caused by mutations in end-processing factors. The majority of SSBs that arise via endogenous damage have ‘dirty’ termini and require end-processing to restore DNA ends with conventional ‘ligatable’ chemistry. Another common feature of these end-processing enzymes is their association with XRCC1, a scaffolding protein that is a core component of SSBR. Complete loss of XRCC1 is embryonically lethal and the conditional deletion of XRCC1 in the developing mouse brain leads to persistent DNA damage, cerebellar interneurons loss and abnormal hippocampal function resulting in behavioural abnormalities such as seizures and episodic epilepsy. Taken together these observations suggest that neural cells are exquisitely sensitive to defects in chromosomal SSBR. In my thesis, I will describe biochemical and cellular data on lymphoblastoid and fibroblast cell lines derived from patients with mutations in the end-processing factors aprataxin (APTX is mutated in AOA1). I will include data showing that aprataxin is required for the short-patch SSBR of abortive ligation intermediates in vitro and that repair arrests in AOA1 cell lines due to insufficient levels of non-adenylated DNA ligase.
Unexplored richness: discovery of 31 new species of giant pill-millipedes endemic to Madagascar, with a special emphasis on microendemism (Diplopoda, Sphaerotheriida)

Thirty-one new species of giant pill-millipedes (order Sphaerotheriida) endemic to Madagascar are described: Zoosphaerium haackeri n. sp. , Z. album n. sp. , Z. discolor n. sp. , Z. mitoho n. sp. , Z. pulchellum n. sp. , Z. endemicum n. sp. , Z. xerophilum n. sp. , Z. aureum n. sp. , Z. pseudopriapus n. sp. , Z. pseudoplatylabum n. sp. , Z. solitarium n. sp. , Z. tsingy n. sp. , Z. corystoides n. sp. , Z. broelemanni n. sp. , Z. amabile n. sp. , Z. trichordum n. sp. , Z. smaragdinum n. sp. , Z. ambrense n. sp. , Z. isalo n. sp. , Z. bilobum n. sp. , Z. tampolo n. sp. , Z. ignotum n. sp. , Z. tainkintana n. sp. , Z. viridissimum n. sp. , Z. denticulatum n. sp. , Z. pseudoblandum n. sp. , Z. micropiligerum n. sp. , Z. pseudopiligerum n. sp. , Z. analavelona n. sp. and Z. fisheri n. sp. , and Microsphaerotherium anjozorobe n. sp. Twenty-eight of the Zoosphaerium species already fit into established species-groups. A key to all 55 recognizable Malagasy Sphaerotheriida species is given. Forty-two of the 55 giant pill-millipede species are ecosystem endemics, while 26 are geographically microendemic. The number of microendemic species is disproportionately distributed among Malagasy ecosystems. All 13 species restricted to the montane rainforest as well as all five species restricted to the Eastern littoral forest are microendemic. On the other hand, only two out of seven dry forest species, one out of seven rainforest species and one out of five spiny forest species are microendemics. A special emphasis is placed on two species endemic to the unique Western rainforest site of Analavelona, which is currently not protected.
Innovación en las empresas: el papel de los sistemas de información

espanolEste trabajo presenta las conclusiones obtenidas en un estudio en el que se utilizo una muestra de 251 empresas espanolas con reconocida excelencia en la gestion de recursos humanos. Los resultados resaltan la necesidad de implementar sistemas de informacion adecuados para promover la innovacion radical. Ademas, es necesario facilitar contextos organizacionales que fomenten la comunicacion, la experimentacion, la toma de riesgos, la toma de decisiones participativa y la apertura de las empresas al entorno externo. EnglishThis work presents the conclusions achieved after conducting a study focused on a sample of 251 Spanish companies with recognized excellence in human resources management. Results highlight the need of implementing adequate information systems to promote radical innovation. In addition, it is necessary to facilitate organizational contexts that encourage dialogue, experimentation, risk-taking, participative decision-making and openness to the external environment.