Discovery of a new group of double-periodic RR Lyrae stars in the OGLE-IV photometry

We report the discovery of a new group of double-periodic RR Lyrae stars from the analysis of the OGLE-IV Galactic bulge photometry. In 11 stars identified in the OGLE catalog as first overtone pulsators (RRc stars) we detect additional longer period variability of low amplitude, in the mmag regime. One additional star of the same type is identified in a published analysis of the Kepler space photometry. The period ratio between the shorter first overtone period and a new, longer period lies in a narrow range around 0.686. Thus, the additional period is longer than the expected period of the undetected radial fundamental mode. The obvious conclusion that addition periodicity corresponds to a gravity or a mixed mode faces difficulties, however.Comment: 5 pages, 4 figures, accepted for publication in MNRAS Letter

Double-mode radial-non-radial RR Lyrae stars. OGLE-IV photometry of two high cadence fields in the Galactic bulge

We analyse the OGLE-IV photometry of the first overtone and double-mode RR Lyrae stars (RRc/RRd) in the two fields towards the Galactic bulge observed with high cadence. In 27 per cent of RRc stars we find additional non-radial mode, with characteristic period ratio, P x /P 1O \in (0.6, 0.64). It strongly corroborates the conclusion arising from the analysis of space photometry of RRc stars, that this form of pulsation must be common. In the Petersen diagram the stars form three sequences. In 20 stars we find two or three close secondary modes simultaneously. The additional modes are clearly non-stationary. Their amplitude and/or phase vary in time. As a result, the patterns observed in the frequency spectra of these stars may be very complex. In some stars the additional modes split into doublets, triplets or appear as a more complex bands of increased power. Subharmonics of additional modes are detected in 20 per cent of stars. They also display a complex structure. Including our previous study of the OGLE-III Galactic bulge data, we have discovered 260 RRc and 2 RRd stars with the additional non-radial mode, which is the largest sample of these stars so far. The additional mode is also detected in two Blazhko RRc stars, which shows that the modulation and additional non-radial mode are not exclusive.Comment: 18 pages, 14 figures, accepted for publication in MNRA

Blazhko effect and the Petersen diagram

Pulsations in RR Lyrae stars and classical Cepheids were thought to be relatively simple since they typically pulsate only in one or two radial modes. This picture changes at a closer look when modulation or additional low-amplitude signals are detected. I will review different multi-periodic groups known among classical pulsators, including stars showing the Blazhko modulation.Comment: Invited review at 2022 RR Lyrae and Cepheids conference on La Palma, 9 pages, 2 figure

Trauma-Informed (As A Matter of) Course

Law students are impacted by trauma and law professors are in a position to help by adopting a trauma-informed approach as a matter of universal precaution. The 2021 Survey of Law Student Well-Being (“SLSWB”) revealed that over twenty percent of responding law students meet criteria that indicate they should be evaluated for post-traumatic stress disorder (“PTSD”). The study also revealed that almost fifty percent of responding students reported an important motivation for attending law school was experiencing a trauma or injustice. Put differently, law schools are full of law students who have experienced trauma, many of whom are actively struggling with trauma. Students are coming to law school not just in spite of their trauma histories but because of their trauma histories. Law schools must respond accordingly. Armed with this new knowledge, legal educators have the opportunity to transgress and transform to provide trauma-informed legal education. It has long been known that legal systems are full of people with trauma histories and that interacting with the legal system can be traumatic. Given the pervasive presence of those with trauma histories in law schools and the legal system, law professors must have a basic understanding of trauma and trauma-informed practices to do their jobs they seek to serve. This Article will explore what law professors need to know about trauma, why law professors need to understand trauma, and how to employ a trauma-informed approach in their doctrinal courses as a matter of universal design. It contributes to existing conversations on trauma-informed better practices and trauma stewardship. Additionally, it provides practical, solution-focused, strengths-based tools for teaching through a trauma-informed lens. It adds to a body of legal scholarship on trauma-informed pedagogy and lawyering and is grounded in scholarship from other disciplines. It also relies on my own learned-experience from my efforts to teach and practice law in a trauma-informed manner

Trauma-Informed (As A Matter of) Course

Law students are impacted by trauma and law professors are in a position to help by adopting a trauma-informed approach as a matter of universal precaution. The 2021 Survey of Law Student Well-Being (“SLSWB”) revealed that over twenty percent of responding law students meet criteria that indicate they should be evaluated for post-traumatic stress disorder (“PTSD”). The study also revealed that almost fifty percent of responding students reported an important motivation for attending law school was experiencing a trauma or injustice. Put differently, law schools are full of law students who have experienced trauma, many of whom are actively struggling with trauma. Students are coming to law school not just in spite of their trauma histories but because of their trauma histories

Empirical, Analytical Methods for Surface Settlement Prediction Due to TBM-Tunnelling in Dutch Soft Soil

TBM-tunnelling in soft soil causes a 3D-ground deformation field, developing in longitudinal direction (parallel to the axis of the tunnel) and transverse direction (perpendicular to the axis of the tunnels). Empirical based methods are used for the prediction of the distribution of ground movements in both directions. Consequently the differential settlements are used to predict the damage risks of adjacent buildings due to TBM-tunnelling in the design stage. The Gaussian-curve is commonly applied for the prediction of green field ground movements transverse to the tunnel axis. Different authors derived methods for determining the characteristic inputparameter i, being the point of inflexion for the settlement trough on surface level for tunnelling projects all over the world. The i-value determines the steepness of the trough. This paper presents a comparison between the different approaches derived from data of projects outside the Netherlands and the field data from three recently bored Dutch tunnelling projects (i.e. the Second Heinenoord Tunnel, the Botlek Railway Tunnel and the Sophia Railway Tunnel). Recommendations are suggested for the use of the empirical methods for Dutch soil conditions representing soft soil and high groundwater level

Getting Out From Under: Transcending Genre and Trauma

Nick and London haven’t seen each other in years, since college graduation, until London arrives at Nick’s bar one night, clearly in trouble. On a whim and with a surge of sympathy, Nick invites London to stay the night. This one night turns into many as the two have to maneuver living with the other, one struggling with mystery, the other with trust. Their walls slowly begin to come down and they fall in love. But London still has secrets that keep her closed off. It takes a lot of strength for her to reveal these secrets and get past what they mean. This project seeks to study how trauma can affect an individual and those around them. It is the story of London overcoming trauma in order to build relationships that have trust and transparency in them; to build relationships that allow her to fully be herself. The genre of chick lit plays a role in some of the conventions in the story, most notably with the romance that forms. The romance is actually a mode of healing for London which pushes back against the large feminist debate that romance plots are a patriarchal structure that don’t allow for autonomy. Getting Out From Under allows romance and autonomy and healing to coexist as well as thrive

Geochemical modelling of water-rock interaction

CO2 geological storage is one of the most promising technologies for reducing atmospheric emissions of greenhouse gas. In this work we present and discuss a new approach geochemical modelling for evaluating the effects of short-medium term CO2 disposal in deep geologic formations that has been tested in the Weyburn test site (Saskatchewan, Canada), where since September 2000 5000 t/day of supercritical CO2 are injected. The geochemical modeling has been performed by using the code PRHEEQC (V2.11) software package, via thermodynamic corrections to the code default database. First, we reconstructed the in-situ reservoir (62°C and 0.1 MPa) chemical composition, including pH, by the chemical equilibrium among the various phases, and we evaluated the boundary conditions (e.g. PCO2 , PH2S), which are necessary for the implementation of reaction path modeling. This is the starting point to assess the geochemical impact of CO2 into the oil reservoir and, as main target, to quantify water-gas-rock reactions. Furthermore, we identified possible compositions of the initially reservoir liquid phases by assuming the equilibrium conditions for the mineral assemblage with respect to a Na-Cl water (Cl/Na=1.2). Then we computed the kinetic evolution of the CO2-rich Weyburn brines interacting with the host-rock minerals, performed over 100 years after injection. Results of reaction path modeling suggest that, in this period, CO2 can be neutralized by solubility (as CO2 (aq)) and mineral trapping through Dawsonite precipitation. In order to validate our geochemical model we have simulated the geochemical impact of three years of CO2 injection (September 2000-2003) by kinetically controlled reactions and we have compared the computed and measured data. The calculated chemical composition after the CO2 injection is consistent with the analytical data of samples collected in 2003 with an error within 5 % for most analytical species, with the exception of the Ca and Mg contents (error > 90%), likely due to the complexation effect of carboxilic acid