Where Have All The Young Men Gone? Evidences and Explanations of Changing Age: Sex Ratios in Kampala

In the second half of the twentieth century the population of Kampala grew substantially and the long-remarked surplus of men over women began to level out. These general trends are equally evident in other African cities, but important differences show up when the balance of age cohorts within the male and female populations is considered. Thus in Kampala, along with population growth and a declining overall sex ratio, censuses show a growing excess of girls/young women over boys/young men. The article reviews these population data and two levels of (unenumerated) explanation for them. The first is extrapolated from Uganda's recent history; the second from observation and narrative in one densely populated parish. The argument is that changes in the age–sex ratio follow from change in the map of work options in Kampala. The disappearance of young males stems from the collapse of the formal economy, once the employer of men, and the developments in the informal economy which favour young women. This conclusion is supported by census data from Nairobi, where the formal employment structure remains relatively buoyant, and the comparable age–sex ratios are less extreme. The health policy relevance of the Kampala trend is underlined by official calculations of increasing HIV/AIDS incidence among teenage women. As long as sex work remains dominant among their options in the informal economy, one effect of their economic advantage is extra vulnerability to fatal disease

Soft Information, Hard Sell: The Role of Soft Information in the Pricing of Intellectual Property

There is a growing literature on the differential impact of soft' vs. hard' information on organizational structure and behavior. This study is an attempt to empirically quantify the value of soft information, using a data-base on the market for screenplays. Script quality is difficult to estimate without subjective evaluation. Therefore soft information should be an integral part of the pricing of these intellectual assets. In our empirical analysis, we find that hard information' (reputation) variables as well as soft information' proxies are priced. Screenplays with high soft information content are priced significantly lower than high concept' harder information'- type scripts. We also follow the screenplays to production, and find that buyers seem to be able to forecast the success of a script, paying more for screenplays resulting in more successful films. In other words, high concept' (harder information) screenplays sell for more and result in more successful movies.

Learning to Dress {3D} People in Generative Clothing

Three-dimensional human body models are widely used in the analysis of human pose and motion. Existing models, however, are learned from minimally-clothed 3D scans and thus do not generalize to the complexity of dressed people in common images and videos. Additionally, current models lack the expressive power needed to represent the complex non-linear geometry of pose-dependent clothing shapes. To address this, we learn a generative 3D mesh model of clothed people from 3D scans with varying pose and clothing. Specifically, we train a conditional Mesh-VAE-GAN to learn the clothing deformation from the SMPL body model, making clothing an additional term in SMPL. Our model is conditioned on both pose and clothing type, giving the ability to draw samples of clothing to dress different body shapes in a variety of styles and poses. To preserve wrinkle detail, our Mesh-VAE-GAN extends patchwise discriminators to 3D meshes. Our model, named CAPE, represents global shape and fine local structure, effectively extending the SMPL body model to clothing. To our knowledge, this is the first generative model that directly dresses 3D human body meshes and generalizes to different poses. The model, code and data are available for research purposes at https://cape.is.tue.mpg.de.Comment: CVPR-2020 camera ready. Code and data are available at https://cape.is.tue.mpg.d

Extensive population synthesis of isolated neutron stars with field decay

We perform population synthesis studies of different types of neutron stars taking into account the magnetic field decay. For the first time, we confront our results with observations using {\it simultaneously} the Log N -- Log S distribution for nearby isolated neutron stars, the Log N -- Log L distribution for magnetars, and the distribution of radio pulsars in the $P$ -- $\dot P$ diagram. We find that our theoretical model is consistent with all sets of data if the initial magnetic field distribution function follows a log-normal law with $\sim 13.25$ and $\sigma_{\log B_0}\sim 0.6$. The typical scenario includes about 10% of neutron stars born as magnetars, significant magnetic field decay during the first million years of a NS life. Evolutionary links between different subclasses may exist, although robust conclusions are not yet possible. We apply the obtained field distribution and the model of decay to study long-term evolution of neuton stars till the stage of accretion from the interstellar medium. It is shown that though the subsonic propeller stage can be relatively long, initially highly magnetized neutron stars ($B_0 > \sim 10^{13}$ G) reach the accretion regime within the Galactic lifetime if their kick velocities are not too large. The fact that in previous studies made $>$10 years ago, such objects were not considered results in a slight increase of the Accretor fraction in comparison with earlier conclusions. Most of the neutron stars similar to the Magnificent seven are expected to become accreting from the interstellar medium after few billion years of their evolution. They are the main predecestors of accreting isolated neutron stars.Comment: 4 pages, conference "Astrophysics of Neutron Stars - 2010" in honor of M. Ali Alpar, Izmir, Turke

Generally covariant theories: the Noether obstruction for realizing certain space-time diffeomorphisms in phase space

Relying on known results of the Noether theory of symmetries extended to constrained systems, it is shown that there exists an obstruction that prevents certain tangent-space diffeomorphisms to be projectable to phase-space, for generally covariant theories. This main result throws new light on the old fact that the algebra of gauge generators in the phase space of General Relativity, or other generally covariant theories, only closes as a soft algebra and not a a Lie algebra. The deep relationship between these two issues is clarified. In particular, we see that the second one may be understood as a side effect of the procedure to solve the first. It is explicitly shown how the adoption of specific metric-dependent diffeomorphisms, as a way to achieve projectability, causes the algebra of gauge generators (constraints) in phase space not to be a Lie algebra --with structure constants-- but a soft algebra --with structure {\it functions}.Comment: 22 pages, version to be published in Classical & Quantum Gravit