Science Education Mythbusters: Challenging the idea of expected grade distributions and “anomalous grades”

As we know with students, unseating misconceptions and deeply held personal myths is a challenging but necessary part of learning. As scientists, we are accustomed to questioning hypotheses and evaluating evidence. However, as science educators, it can be difficult to recognize our own assumptions about teaching/learning, and how they may be affecting our practise.In this session, we will review the literature, weigh the evidence, and discuss misconceptions surrounding grade distributions in science courses. (In a course, is there an expected or ideal grade distribution? An ideal average? Are deviations from expected grade distributions indicative of problems? Are science courses harder than non-science courses, which should be reflected in grade distributions?) Recent cases in Canadian universities have highlighted the controversy surrounding grade distribution policies (Petz, 2010). Approaches to teaching and assessment (and, potentially, tenure and promotion) of science educators may be impacted by university/faculty/departmental grading expectations. A brief overview of the literature will be followed by directed discussion.Possible questions for debate/discussion:1. What are the current practises/policies at our own institutions/departments?2. What effects do the misconceptions have on science students? Faculty members?3. How can improvements in teaching/learning be assessed (i.e., do improvements in grades indicate improved teaching/learning)?4. Is grade inflation actually occurring in science courses? (And, if so, is this a major concern?)5. What strategies are most effective for exploring the topic with colleagues (faculty/TAs)?Reference:Petz, S. 2010. Alberta prof asked to resign over grades dispute. Maclean’s Magazine Blog: http://oncampus.macleans.ca/education/2010/12/31/alberta-prof-asked-to-resign-over-grades-dispute/ Retrieved May 31, 2011

Worst-Case Morphs Using Wasserstein ALI and Improved MIPGAN

A morph is a combination of two separate facial images and contains the identity information of two different people. When used in an identity document, both people can be authenticated by a biometric face recognition (FR) system. Morphs can be generated using either a landmark-based approach or approaches based on deep learning, such as generative adversarial networks (GANs). In a recent paper, we introduced a worst-case upper bound on how challenging morphing attacks can be for an FR system. The closer morphs are to this upper bound, the bigger the challenge they pose to FR. We introduced an approach with which it was possible to generate morphs that approximate this upper bound for a known FR system (white box) but not for unknown (black box) FR systems. In this paper, we introduce a morph generation method that can approximate worst-case morphs even when the FR system is not known. A key contribution is that we include the goal of generating difficult morphs during training. Our method is based on adversarially learned inference (ALI) and uses concepts from Wasserstein GANs trained with gradient penalty, which were introduced to stabilise the training of GANs. We include these concepts to achieve a similar improvement in training stability and call the resulting method Wasserstein ALI (WALI). We finetune WALI using loss functions designed specifically to improve the ability to manipulate identity information in facial images and show how it can generate morphs that are more challenging for FR systems than landmark- or GAN-based morphs. We also show how our findings can be used to improve MIPGAN, an existing StyleGAN-based morph generator

Knowledge Gaps in the Fetal to Neonatal Transition of Infants With a Congenital Diaphragmatic Hernia

Clinical research for infants born with a congenital diaphragmatic hernia (CDH) has until recently mainly focused on advances in prenatal and postnatal treatment. However, during the early perinatal transition period there are major physiological adaptations. For most infants these changes will happen uneventfully, but for CDH infants this marks the beginning of serious respiratory complications. In recent years, there is emerging evidence that the clinical management during the perinatal stabilization period in the delivery room may influence postnatal outcomes. Herein, we discuss major knowledge gaps and novel concepts that aim to optimize fetal to neonatal transition for infants with CDH. One such novel and interesting approach is performing resuscitation with an intact umbilical cord, the efficacy of this procedure is currently being investigated in several clinical trials. Furthermore, close evaluation of neonatal physiological parameters in the first 24 h of life might provide early clues concerning the severity of lung hypoplasia and the risk of adverse outcomes. We will provide an overview of trending concepts and discuss potential areas for future research

Channel Coupling in A(e⃗,e′N⃗)BA(\vec{e},e' \vec{N})B Reactions

The sensitivity of momentum distributions, recoil polarization observables, and response functions for nucleon knockout by polarized electrons to channel coupling in final-state interactions is investigated using a model in which both the distorting and the coupling potentials are constructed by folding density-dependent effective interactions with nuclear transition densities. Calculations for $^{16}$O are presented for 200 and 433 MeV ejectile energies, corresponding to proposed experiments at MAMI and TJNAF, and for $^{12}$C at 70 and 270 MeV, corresponding to experiments at NIKHEF and MIT-Bates. The relative importance of charge exchange decreases as the ejectile energy increases, but remains significant for 200 MeV. Both proton and neutron knockout cross sections for large recoil momenta, $p_m > 300$ MeV/c, are substantially affected by inelastic couplings even at 433 MeV. Significant effects on the cross section for neutron knockout are also predicted at smaller recoil momenta, especially for low energies. Polarization transfer for proton knockout is insensitive to channel coupling, even for fairly low ejectile energies, but polarization transfer for neutron knockout retains nonnegligible sensitivity to channel coupling for energies up to about 200 MeV. The present results suggest that possible medium modifications of neutron and proton electromagnetic form factors for $Q^2 \gtrsim 0.5 (GeV/c)^2$ can be studied using recoil polarization with relatively little sensitivity due to final state interactions.Comment: Substantially revised version accepted by Phys. Rev. C; shortened to 49 pages including 21 figure

Physiological-based cord clamping versus immediate cord clamping for infants born with a congenital diaphragmatic hernia (PinC):study protocol for a multicentre, randomised controlled trial

Introduction Pulmonary hypertension is a majordeterminant of postnatal survival in infants with acongenital diaphragmatic hernia (CDH). The current careduring the perinatal stabilisation period in these infantsmight contribute to the development of pulmonaryhypertension after birth—in particular umbilical cordclamping before lung aeration. An ovine model ofdiaphragmatic hernia demonstrated that cord clampingafter lung aeration, called physiological-based cordclamping (PBCC), avoided the initial high pressures in thelung vasculature while maintaining adequate blood flow,thereby avoiding vascular remodelling and aggravationof pulmonary hypertension. We aim to investigate if theimplementation of PBCC in the perinatal stabilisation periodof infants born with a CDH could reduce the incidence ofpulmonary hypertension in the first 24 hours after birth.Methods and analysis We will perform a multicentre,randomised controlled trial in infants with an isolatedleft-sided CDH, born at ≥35.0 weeks. Before birth, infantswill be randomised to either PBCC or immediate cordclamping, stratified by treatment centre and severity ofpulmonary hypoplasia on antenatal ultrasound. PBCCwill be performed using a purpose- built resuscitationtrolley. Cord clamping will be performed when the infantis considered respiratory stable, defined as a heartrate >100 bpm, preductal oxygen saturation >85%,while using a fraction of inspired oxygen of <0.5. Theprimary outcome is pulmonary hypertension diagnosedin the first 24 hours after birth, based on clinical andechocardiographic parameters. Secondary outcomesinclude neonatal as well as maternal outcomes.Ethics and dissemination Central ethical approvalwas obtained from the Medical Ethical Committee ofthe Erasmus MC, Rotterdam, The Netherlands (METC2019-0414). Local ethical approval will be obtained bysubmitting the protocol to the regulatory bodies and localinstitutional review boards

Cosmological distance indicators

We review three distance measurement techniques beyond the local universe: (1) gravitational lens time delays, (2) baryon acoustic oscillation (BAO), and (3) HI intensity mapping. We describe the principles and theory behind each method, the ingredients needed for measuring such distances, the current observational results, and future prospects. Time delays from strongly lensed quasars currently provide constraints on $H_0$ with < 4% uncertainty, and with 1% within reach from ongoing surveys and efforts. Recent exciting discoveries of strongly lensed supernovae hold great promise for time-delay cosmography. BAO features have been detected in redshift surveys up to z <~ 0.8 with galaxies and z ~ 2 with Ly-$\alpha$ forest, providing precise distance measurements and $H_0$ with < 2% uncertainty in flat $\Lambda$CDM. Future BAO surveys will probe the distance scale with percent-level precision. HI intensity mapping has great potential to map BAO distances at z ~ 0.8 and beyond with precisions of a few percent. The next years ahead will be exciting as various cosmological probes reach 1% uncertainty in determining $H_0$, to assess the current tension in $H_0$ measurements that could indicate new physics.Comment: Review article accepted for publication in Space Science Reviews (Springer), 45 pages, 10 figures. Chapter of a special collection resulting from the May 2016 ISSI-BJ workshop on Astronomical Distance Determination in the Space Ag

Relativistic corrections in (gamma,N) knockout reactions

We develop a fully relativistic DWIA model for photonuclear reactions using the relativistic mean field theory for the bound state and the Pauli reduction of the scattering state which is calculated from a relativistic optical potential. Results for the 12C(gamma,p) and 16O(gamma,p) differential cross sections and photon asymmetries are displayed in a photon energy range between 60 and 257 MeV, and compared with nonrelativistic DWIA calculations. The effects of the spinor distortion and of the effective momentum approximation for the scattering state are discussed. The sensitivity of the model to different prescriptions for the one-body current operator is investigated. The off-shell ambiguities are large in (gamma,p) calculations, and even larger in (gamma,n) knockout.Comment: LaTeX2e, 18 pages, and 6 figure

IKK-induced NF-kappa B1 p105 proteolysis is critical for B cell antibody responses to T cell-dependent antigen

The importance of IκB kinase (IKK)–induced proteolysis of NF-κB1 p105 in B cells was investigated using Nfkb1SSAA/SSAA mice, in which this NF-κB signaling pathway is blocked. Nfkb1SSAA mutation had no effect on the development and homeostasis of follicular mature (FM) B cells. However, analysis of mixed bone marrow chimeras revealed that Nfkb1SSAA/SSAA FM B cells were completely unable to mediate T cell–dependent antibody responses. Nfkb1SSAA mutation decreased B cell antigen receptor (BCR) activation of NF-κB in FM B cells, which selectively blocked BCR stimulation of cell survival and antigen-induced differentiation into plasmablasts and germinal center B cells due to reduced expression of Bcl-2 family proteins and IRF4, respectively. In contrast, the antigen-presenting function of FM B cells and their BCR-induced migration to the follicle T cell zone border, as well as their growth and proliferation after BCR stimulation, were not affected. All of the inhibitory effects of Nfkb1SSAA mutation on B cell functions were rescued by normalizing NF-κB activation genetically. Our study identifies critical B cell-intrinsic functions for IKK-induced NF-κB1 p105 proteolysis in the antigen-induced survival and differentiation of FM B cells, which are essential for T-dependent antibody responses

Standalone vertex finding in the ATLAS muon spectrometer

A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths. The performance of the algorithm is evaluated using both a sample of simulated Higgs boson events, in which the Higgs boson decays to long-lived neutral particles that in turn decay to bbar b final states, and pp collision data at √s = 7 TeV collected with the ATLAS detector at the LHC during 2011

Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC

Measurements are presented of production properties and couplings of the recently discovered Higgs boson using the decays into boson pairs, H →γ γ, H → Z Z∗ →4l and H →W W∗ →lνlν. The results are based on the complete pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV, corresponding to an integrated luminosity of about 25 fb−1. Evidence for Higgs boson production through vector-boson fusion is reported. Results of combined fits probing Higgs boson couplings to fermions and bosons, as well as anomalous contributions to loop-induced production and decay modes, are presented. All measurements are consistent with expectations for the Standard Model Higgs boson