Gender-differentiated effects of parenthood on earnings: Understanding cross-national variation in the motherhood penalty and fatherhood bonus

Although mothers are increasingly joining the labor force, employers continue to pay mothers less than non-mothers and fathers more than non-fathers. Using data from the Luxembourg Income Study (LIS), this paper investigates the influence of parental status on the incomes of men and women in eight industrialized countries. I demonstrate the existence of an employer bias against mothers in all countries except the Netherlands and a bias toward fathers in all countries except the Netherlands and Luxembourg. I then compare three methods for categorizing countries based on gender equality to see which best explains the cross-national variation in motherhood penalties and fatherhood bonuses

Transient Heat Storage Systems

Phase change materials (PCM) have many applications in transient cooling systems, including those with high transient heat loads and low duty cycles. These materials allow a system to remain within a narrow temperature range with a relatively low weight compared to conventional heat sinks or high-power cooling systems. This senior capstone project includes the design of a PCM based thermal energy storage system to integrate into an existing cooling loop, as well as a determination of viable PCM’s for the application. This report contains the necessary information to build the test apparatus

Algorithms to estimate Shapley value feature attributions

Feature attributions based on the Shapley value are popular for explaining machine learning models; however, their estimation is complex from both a theoretical and computational standpoint. We disentangle this complexity into two factors: (1)~the approach to removing feature information, and (2)~the tractable estimation strategy. These two factors provide a natural lens through which we can better understand and compare 24 distinct algorithms. Based on the various feature removal approaches, we describe the multiple types of Shapley value feature attributions and methods to calculate each one. Then, based on the tractable estimation strategies, we characterize two distinct families of approaches: model-agnostic and model-specific approximations. For the model-agnostic approximations, we benchmark a wide class of estimation approaches and tie them to alternative yet equivalent characterizations of the Shapley value. For the model-specific approximations, we clarify the assumptions crucial to each method's tractability for linear, tree, and deep models. Finally, we identify gaps in the literature and promising future research directions

Novel Microdialysis Technique Reveals a Dramatic Shift in Metabolite Secretion during the Early Stages of the Interaction between the Ectomycorrhizal Fungus Pisolithus microcarpus and Its Host Eucalyptus grandis

The colonisation of tree roots by ectomycorrhizal (ECM) fungi is the result of numerous signalling exchanges between organisms, many of which occur before physical contact. However, information is lacking about these exchanges and the compounds that are secreted by each organism before contact. This is in part due to a lack of low disturbance sampling methods with sufficient temporal and spatial resolution to capture these exchanges. Using a novel in situ microdialysis approach, we sampled metabolites released from Eucalyptus grandis and Pisolithus microcarpus independently and during indirect contact over a 48-h time-course using UPLC-MS. A total of 560 and 1530 molecular features (MFs; ESI- and ESI+ respectively) were identified with significant differential abundance from control treatments. We observed that indirect contact between organisms altered the secretion of MFs to produce a distinct metabolomic profile compared to either organism independently. Many of these MFs were produced within the first hour of contact and included several phenylpropanoids, fatty acids and organic acids. These findings show that the secreted metabolome, particularly of the ECM fungus, can rapidly shift during the early stages of pre-symbiotic contact and highlight the importance of observing these early interactions in greater detail. We present microdialysis as a useful tool for examining plant-fungal signalling with high temporal resolution and with minimal experimental disturbance

The state of play between managing major sport events and human rights:a scoping review

This scoping review integrates literature from diverse perspectives to better understand when and how management of major sport events promotes or harms human rights. The authors critically review 130 peer-reviewed English language articles to identify conceptual contributions to research and practice. The findings reveal that politics and political reform, legal frameworks, and organizational actions are crucial influences in when and how management of events promotes or harms human rights. The most frequently considered rights in the literature are: equality, human trafficking related, sport as a human right, worker rights, and freedom of residence. Activism for human rights stimulates change within relevant stakeholders via collaboration, naming and shaming, in-public debates, and media coverage. The committed, transparent, and inclusive consideration of human rights in all stages of managing sport events (from bid preparation, bidding, planning, and hosting to postevent leverage) may increase the likelihood that the event has social benefits

The origins of unpredictability in life trajectory prediction tasks

Why are life trajectories difficult to predict? We investigated this question through in-depth qualitative interviews with 40 families sampled from a multi-decade longitudinal study. Our sampling and interviewing process were informed by the earlier efforts of hundreds of researchers to predict life outcomes for participants in this study. The qualitative evidence we uncovered in these interviews combined with a well-known mathematical decomposition of prediction error helps us identify some origins of unpredictability and create a new conceptual framework. Our specific evidence and our more general framework suggest that unpredictability should be expected in many life trajectory prediction tasks, even in the presence of complex algorithms and large datasets. Our work also provides a foundation for future empirical and theoretical work on unpredictability in human lives.Comment: 54 pages, 8 figure

Detection of Elements at All Three r-process Peaks in the Metal-Poor Star HD 160617

We report the first detection of elements at all three r-process peaks in the metal-poor halo star HD 160617. These elements include arsenic and selenium, which have not been detected previously in halo stars, and the elements tellurium, osmium, iridium, and platinum, which have been detected previously. Absorption lines of these elements are found in archive observations made with the Space Telescope Imaging Spectrograph onboard the Hubble Space Telescope. We present up-to-date absolute atomic transition probabilities and complete line component patterns for these elements. Additional archival spectra of this star from several ground-based instruments allow us to derive abundances or upper limits of 45 elements in HD 160617, including 27 elements produced by neutron-capture reactions. The average abundances of the elements at the three r-process peaks are similar to the predicted solar system r-process residuals when scaled to the abundances in the rare earth element domain. This result for arsenic and selenium may be surprising in light of predictions that the production of the lightest r-process elements generally should be decoupled from the heavier r-process elements.Comment: Published in the Astrophysical Journal (22 pages, 12 figures