Tate-Shafarevich groups of constant elliptic curves and isogeny volcanos

We describe the structure of Tate-Shafarevich groups of a constant elliptic curves over function fields by exploiting the volcano structure of isogeny graphs of elliptic curves over finite fields

RNA foldings, Oriented Stuck Knots and State Sum Invariants

We extend the quandle cocycle invariant to the context of stuck links. More precisely, we define an invariant of stuck links by assigning Boltzmann weights at both classical and stuck crossings. As an application, we define a single-variable and a two-variable polynomial invariant of stuck links. Furthermore, we define a single-variable and two-variable polynomial invariant of arc diagrams of RNA foldings. We provide explicit computations of the new invariants

The Brauer-Manin obstruction for constant curves over global function fields

Let F be a finite field and C, D smooth, geometrically irreducible, proper curves over F and set K = F(D). We consider Brauer-Manin and abelian descent obstructions to the existence of rational points and to weak approximation for the curve C ⊗F K. In particular, we show that Brauer-Manin is the only obstruction to weak approximation and the Hasse principle in the case that the genus of D is less than that of C. We also show that we can identify the points corresponding to non-constant maps D → C using Frobenius descents

Bluetooth 5.0 Suitability Assessment for Emergency Response within Fire Environments

Natural disasters, such as wildfires, can cause widespread devastation. Future-proofing infrastructure, such as buildings and bridges, through technological advancements is crucial to minimize their impact. Fires in disasters often stem from damaged fuel lines and electrical equipment, such as the 2018 California wildfire caused by a power line fault. To enhance safety, IoT applications can continuously monitor the health of emergency personnel. Using Bluetooth 5.0 and wearables in mesh networks, these apps can alert others about an individual’s location during emergencies. However, fire can disrupt wireless networks. This study assesses Bluetooth 5.0’s performance in transmitting signals in fire conditions. It examined received signal strength indicator (RSSI) values in a front open-fire chamber using both Peer-to-Peer (P2P) and mesh networks. The experiment considered three transmission heights of 0.61, 1.22, and 1.83 m and two distances of 11.13 m and 1.52 m. The study demonstrated successful signal transmission with a maximum loss of only 2 dB when transmitting through the fire. This research underscores the potential for reliable communication in fire-prone environments, improving safety during natural disasters

Mind over mood: exploring the executive function’s role in downregulation

Emotion regulation plays a key role in well adapted behaviour, however, factors influencing individual differences in ER are still under investigation. Across two studies we investigate the complex relationship between executive functions (EFs) and emotional downregulation through two complementary research designs. The focus lies on key components of EFs—working memory, inhibitory control, and switching—and their relationship with effective emotional regulation. Surprisingly, switching emerged as the sole significant predictor in two multiple linear regression models, challenging the conventional belief that all major EFs broadly contribute to emotional downregulation. The first study, involving 248 Ecuadorian adults between 18 and 60 years old, used experimental tasks to assess the association between EFs and emotional regulation, aligning with existing literature that posits a link between EFs and emotional control. The second study, involving 180 Ecuadorian adults between 18 and 43 years old, added depth by incorporating self-report measures, providing a broader, ecologically valid perspective. However, these measures did not significantly predict downregulation, highlighting a gap between self-perception and actual cognitive abilities. Additionally, demographic predictors varied between the two studies, urging future research to consider methodological design and task selection carefully. The study also raises questions about the validity of commonly used measures, emphasising the need for more nuanced tools to capture the complexity of EFs and emotional regulation. Our findings suggest a targeted research avenue focusing on EFs for both future research and clinical interventions. Attention is called to the methodological decisions that can influence the observed associations, and the need for broader demographic representation in future studies

The Web@classroom project: portables computers and wireless technology in the classroom

The study was carried out in four European schools (pupils age 9 to13 years old) within four countries (Portugal, Spain, UK and Ireland). The adopted methodology was based in action-research procedures and it included multiple methods and techniques: systematic classroom observation of teachers and pupil work and learning activities; documentary evidence (teachers working sheets, schemes of work) interviews (with selected pupils); questionnaires to all pupils and staff at intervals. This methodology implied the construction and testing of data collection instruments. Data was submitted to a qualitative and quantitative analysis. A summary of the findings is presented in this text.The study was carried out in four European schools (pupils age 9 to13 years old) within four countries (Portugal, Spain, UK and Ireland). The adopted methodology was based in action-research procedures and it included multiple methods and techniques: systematic classroom observation of teachers and pupil work and learning activities; documentary evidence (teachers working sheets, schemes of work) interviews (with selected pupils); questionnaires to all pupils and staff at intervals. This methodology implied the construction and testing of data collection instruments. Data was submitted to a qualitative and quantitative analysis. A summary of the findings is presented in this text

Derivation and maintenance of mouse haploid embryonic stem cells.

Ploidy represents the number of chromosome sets in a cell. Although gametes have a haploid genome (n), most mammalian cells have diploid genomes (2n). The diploid status of most cells correlates with the number of probable alleles for each autosomal gene and makes it difficult to target these genes via mutagenesis techniques. Here, we describe a 7-week protocol for the derivation of mouse haploid embryonic stem cells (hESCs) from female gametes that also outlines how to maintain the cells once derived. We detail additional procedures that can be used with cell lines obtained from the mouse Haplobank, a biobank of >100,000 individual mouse hESC lines with targeted mutations in 16,970 genes. hESCs can spontaneously diploidize and can be maintained in both haploid and diploid states. Mouse hESCs are genomically and karyotypically stable, are innately immortal and isogenic, and can be derived in an array of differentiated cell types; they are thus highly amenable to genetic screens and to defining molecular connectivity pathways.UK Dementia Research Institute fellowship (MC_PC_17111)

Edge-Coupling of O-Band InP Etched-Facet Lasers to Polymer Waveguides on SOI by Micro-Transfer-Printing

O-band InP etched facets lasers were heterogeneously integrated by micro-transfer-printing into a 1.54~\mu \text{m} deep recess created in the 3~\mu \text{m} thick oxide layer of a 220 nm SOI wafer. A 7\times 1.5\,\,\mu \text{m}^{2} cross-section, 2 mm long multimode polymer waveguide was aligned to the ridge post-integration by e-beam lithography with \u3c 0.7~\mu \text{m} lateral misalignment and incorporated a tapered silicon waveguide. A 170 nm thick metal layer positioned at the bottom of the recess adjusts the vertical alignment of the laser and serves as a thermal via to sink the heat to the Si substrate. This strategy shows a roadmap for active polymer waveguide-based photonic integrated circuits