Insect Diapause

Our highly seasonal world restricts insect activity to brief portions of the year. This feature necessitates a sophisticated interpretation of seasonal changes and enactment of mechanisms for bringing development to a halt and then reinitiating it when the inimical season is past. The dormant state of diapause serves to bridge the unfavourable seasons, and its timing provides a powerful mechanism for synchronizing insect development. This book explores how seasonal signals are monitored and used by insects to enact specific molecular pathways that generate the diapause phenotype. The broad perspective offered here scales from the ecological to the molecular and thus provides a comprehensive view of this exciting and vibrant research field, offering insights on topics ranging from pest management, evolution, speciation, climate change and disease transmission, to human health, as well as analogies with other forms of invertebrate dormancy and mammalian hibernation.

“How will you construct a pathway system?”: Microanalysis of teacher-child scientific conversations

During the preschool years, children’s question-explanation exchanges with teachers serve as a powerful mechanism for their early STEM knowledge acquisition. Utilizing naturalistic longitudinal classroom data, we examined how such conversations in an inquiry-based preschool classroom change during an extended scientific inquiry unit. We were particularly interested in information-seeking questions (causal, e.g. “How will you construct a pathway?”; fact-based, e.g., “Where’s the marble?”). Videos (n = 18; 14 hours) were collected during a three-week inquiry unit on forces and motion and transcribed in CLAN-CHILDES software at the utterance level. Utterances were coded for delivery (question vs. statement) and content (e.g., fact-based, causal). Although teachers ask more questions than children, we found a significant increase in information-seeking questions during Weeks 2 and 3. We explored the content of information-seeking questions and found that the majority of these questions were asked by teachers, and focused on facts. However, the timing of fact-based and causal questions varied. Whereas more causal questions occurred in earlier weeks, more fact-based questions were asked towards the end of the inquiry. These findings provide insight into how children’s and teacher’s questions develop during an inquiry, informing our understanding of early science learning. Even in an inquiry-learning environment, teachers guide interactions, asking questions to support children’s learning. Children’s information-seeking questions increase during certain weeks, suggesting that providing opportunities to ask questions may allow children to be more active in constructing knowledge. Such findings are important for considering how science questions are naturally embedded in an inquiry-based learning classroom.

The impact of fear in the post covid era

Feeling fear is involuntary, as it is often unconscious. However, there are other faces of fear that we can recognize and that are familiar to us. We go from real fears to unreal fears, from present fears to projective fears that are reinforced and mutate into other more complex situations that further reinforce our fear. The more we reinforce these thoughts the stronger our fear becomes. So, what is feeding our fear? How do we react to fear? Is it the desire to dodge the blow, to strike back, to attack it? Fear is a very powerful mechanism that should only be activated in dangerous situations. If we use fear for educational purposes we will project very deep blockages in the new generations. However, when we recognize and accompany the thoughts and impulses generated by fear, they become silent. Once silenced, they are no longer activated unconsciously. Therefore, if we look at what is happening, consciously, "without judgement" it will facilitate our journey towards our true SELF. The EmocionaTFamilia program invites us to accompany our path "lightly and at the right time". Change is simple, the lesson is the opposite of what we have learned.

Towards Improving Code Stylometry Analysis in Underground Forums

Code Stylometry has emerged as a powerful mechanism to identify programmers. While there have been significant advances in the field, existing mechanisms underperform in challenging domains. One such domain is studying the provenance of code shared in underground forums, where code posts tend to have small or incomplete source code fragments. This paper proposes a method designed to deal with the idiosyncrasies of code snippets shared in these forums. Our system fuses a forum-specific learning pipeline with Conformal Prediction to generate predictions with precise confidence levels as a novelty. We see that identifying unreliable code snippets is paramount to generate high-accuracy predictions, and this is a task where traditional learning settings fail. Overall, our method performs as twice as well as the state-of-the-art in a constrained setting with a large number of authors (i.e., 100). When dealing with a smaller number of authors (i.e., 20), it performs at high accuracy (89%). We also evaluate our work on an open-world assumption and see that our method is more effective at retaining samples.

Engines of change: Transposable element mutation rates are high and variable within Daphnia magna

Transposable elements (TEs) represent a major portion of most eukaryotic genomes, yet little is known about their mutation rates or how their activity is shaped by other evolutionary forces. Here, we compare short- and long-term patterns of genome-wide mutation accumulation (MA) of TEs among 9 genotypes from three populations of Daphnia magna from across a latitudinal gradient. While the overall proportion of the genome comprised of TEs is highly similar among genotypes from Finland, Germany, and Israel, populations are distinguishable based on patterns of insertion site polymorphism. Our direct rate estimates indicate TE movement is highly variable (net rates ranging from -11.98 to 12.79 x 10−5 per copy per generation among genotypes), differing both among populations and TE families. Although gains outnumber losses when selection is minimized, both types of events appear to be highly deleterious based on their low frequency in control lines where propagation is not limited to random, single-progeny descent. With rate estimates 4 orders of magnitude higher than base substitutions, TEs clearly represent a highly mutagenic force in the genome. Quantifying patterns of intra- and interspecific variation in TE mobility with and without selection provides insight into a powerful mechanism generating genetic variation in the genome.

Significant DBSCAN+: Statistically Robust Density-based Clustering

Cluster detection is important and widely used in a variety of applications, including public health, public safety, transportation, and so on. Given a collection of data points, we aim to detect density-connected spatial clusters with varying geometric shapes and densities, under the constraint that the clusters are statistically significant. The problem is challenging, because many societal applications and domain science studies have low tolerance for spurious results, and clusters may have arbitrary shapes and varying densities. As a classical topic in data mining and learning, a myriad of techniques have been developed to detect clusters with both varying shapes and densities (e.g., density-based, hierarchical, spectral, or deep clustering methods). However, the vast majority of these techniques do not consider statistical rigor and are susceptible to detecting spurious clusters formed as a result of natural randomness. On the other hand, scan statistic approaches explicitly control the rate of spurious results, but they typically assume a single “hotspot” of over-density and many rely on further assumptions such as a tessellated input space. To unite the strengths of both lines of work, we propose a statistically robust formulation of a multi-scale DBSCAN, namely Significant DBSCAN+, to identify significant clusters that are density connected. As we will show, incorporation of statistical rigor is a powerful mechanism that allows the new Significant DBSCAN+ to outperform state-of-the-art clustering techniques in various scenarios. We also propose computational enhancements to speed-up the proposed approach. Experiment results show that Significant DBSCAN+ can simultaneously improve the success rate of true cluster detection (e.g., 10–20% increases in absolute F1 scores) and substantially reduce the rate of spurious results (e.g., from thousands/hundreds of spurious detections to none or just a few across 100 datasets), and the acceleration methods can improve the efficiency for both clustered and non-clustered data.

A Study of Hegemony and Class Conflict in Gaskel’s North And South

The paper discusses the relation between the north and south as two different geographical locations in the novel. By focusing on them, the article focuses on the hegemonic role of the classes and the emerging conflict. The conflict seems to be fought on industrial grounds but it relates to an intellectual and political awareness that plays a vital role in the sustenance of the ideological changes that take birth. The grave relationship of both classes is not controlled by sheer force but by a well thought out plan that plays a vital role delaying the emergence of a revolution in the working class. The void between the classes is sustained by a powerful mechanism which is indirectly ruling the entire arena of factories their workers and unions. Ironically the unions that are supposed to secure the lives and rights of the working class fall prey to the power of the industrialist.

Die Endozytose — ein zellulärer Aufnahmeweg mit vielfältigen Funktionen

The plasma membrane harbors a specific set of transmembrane proteins which enable diverse cellular functions such as nutrient uptake, ion homeostasis and cellular signaling. The surface levels of these proteins need to be dynamically regulated to allow for plastic changes in cellular behaviour e. g. upon cell stress or during neuronal communication. Endocytosis is a powerful mechanism for quickly adapting the surface proteome via protein internalization. Here, I discuss how endocytosis contributes to brain function and counteracts cell stress.

Tau and Membranes: Interactions That Promote Folding and Condensation

Tau misfolding and assembly is linked to a number of neurodegenerative diseases collectively described as tauopathies, including Alzheimer’s disease (AD) and Parkinson’s disease. Anionic cellular membranes, such as the cytosolic leaflet of the plasma membrane, are sites that concentrate and neutralize tau, primarily due to electrostatic interactions with tau’s microtubule binding repeat domain (RD). In addition to electrostatic interactions with lipids, tau also has interactions with membrane proteins, which are important for tau’s cellular functions. Tau also interacts with lipid tails to facilitate direct translocation across the membrane and can form stable protein-lipid complexes involved in cell-to-cell transport. Concentrated tau monomers at the membrane surface can form reversible condensates, change secondary structures, and induce oligomers, which may eventually undergo irreversible crosslinking and fibril formation. These β-sheet rich tau structures are capable of disrupting membrane organization and are toxic in cell-based assays. Given the evidence for relevant membrane-based tau assembly, we review the emerging hypothesis that polyanionic membranes may serve as a site for phase-separated tau condensation. Membrane-mediated phase separation may have important implications for regulating tau folding/misfolding, and may be a powerful mechanism to spatially direct tau for native membrane-mediated functions.

Partitioning of REE between calcite and carbonatitic melt containing P, S, Si at 900-650 °C and 100 MPa

Many carbonatites host deposits of REE and HFSE, and fractional crystallization might be a potentially powerful mechanism controlling magma enrichment by these metals to economically significant values. At present, information about the control of fractional crystallization by partition coefficients of ore-forming elements at magmatic stage is incomplete. Here we present an experimental study of REE partitioning between carbonatite melt and calcite in the system CaCO3-Na2CO3 with varying amounts of P2O5, F, Cl, SiO2, SO3 at 650–900°C and 100 MPa using cold-seal pressure vessels and LA-ICP-MS. The presence of phosphorus in the system generally increases the distribution coefficients but its effect decreases with increasing concentration. The influence of temperature is great: at 900 − 770°C DREE ≥1, while at lower temperatures the values are below unity. Silicon also promotes the fractionation of REE into calcite, while sulfur contributes to the retention of REE in the melt. Our results imply that calcite may impose significant control upon REE fractionation at the early stages of crystallization of carbonatite magma and can be a closest proxy for monitoring the REE content in initial melt.