Lifting homotopy T-algebra maps to strict maps

The settings for homotopical algebra---categories such as simplicial groups, simplicial rings, $A_\infty$ spaces, $E_\infty$ ring spectra, etc.---are often equivalent to categories of algebras over some monad or triple $T$. In such cases, $T$ is acting on a nice simplicial model category in such a way that $T$ descends to a monad on the homotopy category and defines a category of homotopy $T$-algebras. In this setting there is a forgetful functor from the homotopy category of $T$-algebras to the category of homotopy $T$-algebras. Under suitable hypotheses we provide an obstruction theory, in the form of a Bousfield-Kan spectral sequence, for lifting a homotopy $T$-algebra map to a strict map of $T$-algebras. Once we have a map of $T$-algebras to serve as a basepoint, the spectral sequence computes the homotopy groups of the space of $T$-algebra maps and the edge homomorphism on $\pi_0$ is the aforementioned forgetful functor. We discuss a variety of settings in which the required hypotheses are satisfied, including monads arising from algebraic theories and operads. We also give sufficient conditions for the $E_2$-term to be calculable in terms of Quillen cohomology groups. We provide worked examples in $G$-spaces, $G$-spectra, rational $E_\infty$ algebras, and $A_\infty$ algebras. Explicit calculations, connected to rational unstable homotopy theory, show that the forgetful functor from the homotopy category of $E_\infty$ ring spectra to the category of $H_\infty$ ring spectra is generally neither full nor faithful. We also apply a result of the second named author and Nick Kuhn to compute the homotopy type of the space $E_\infty(\Sigma^\infty_+ \mathrm{Coker}\, J, L_{K(2)} R)$.Comment: 45 pages. Substantial revision. To appear in Advances in Mathematic

Estimates of the Planet Yield from Ground-based High-contrast Imaging Observations as a Function of Stellar Mass

We use Monte Carlo simulations to estimate the number of extrasolar planets that are directly detectable in the solar neighborhood using current and forthcoming high-contrast imaging instruments. Our calculations take into consideration the important factors that govern the likelihood for imaging a planet, including the statistical properties of stars in the solar neighborhood, correlations between star and planet properties, observational effects, and selection criteria. We consider several different ground-based surveys, both biased and unbiased, and express the resulting planet yields as a function of stellar mass. Selecting targets based on their youth and visual brightness, we find that strong correlations between star mass and planet properties are required to reproduce high-contrast imaging results to date (i.e., HR 8799, β Pic). Using the most recent empirical findings for the occurrence rate of gas-giant planets from radial velocity (RV) surveys, our simulations indicate that naive extrapolation of the Doppler planet population to semimajor axes accessible to high-contrast instruments provides an excellent agreement between simulations and observations using present-day contrast levels. In addition to being intrinsically young and sufficiently bright to serve as their own beacon for adaptive optics correction, A-stars have a high planet occurrence rate and propensity to form massive planets in wide orbits, making them ideal targets. The same effects responsible for creating a multitude of detectable planets around massive stars conspire to reduce the number orbiting low-mass stars. However, in the case of a young stellar cluster, where targets are approximately the same age and situated at roughly the same distance, MK-stars can easily dominate the number of detections because of an observational bias related to small number statistics. The degree to which low-mass stars produce the most planet detections in this special case depends upon whether multiple formation mechanisms are at work. Upon relaxing our assumption that planets in ultra-wide (a > 100 AU) orbits resemble the RV sample, our simulations suggest that the companions found orbiting late-type stars (AB Pic, 1RXSJ1609, GSC 06214, etc.) are consistent with a formation channel distinct from that of RV planets. These calculations explain why planets have thus far been imaged preferentially around A-stars and K-, M-stars, but no spectral types in between, despite concerted efforts targeting F-, G-stars

Love Thy Neighbors: Image Annotation by Exploiting Image Metadata

Some images that are difficult to recognize on their own may become more clear in the context of a neighborhood of related images with similar social-network metadata. We build on this intuition to improve multilabel image annotation. Our model uses image metadata nonparametrically to generate neighborhoods of related images using Jaccard similarities, then uses a deep neural network to blend visual information from the image and its neighbors. Prior work typically models image metadata parametrically, in contrast, our nonparametric treatment allows our model to perform well even when the vocabulary of metadata changes between training and testing. We perform comprehensive experiments on the NUS-WIDE dataset, where we show that our model outperforms state-of-the-art methods for multilabel image annotation even when our model is forced to generalize to new types of metadata.Comment: Accepted to ICCV 201

Protein import into the endosymbiotic organelles of apicomplexan parasites

The organelles of endosymbiotic origin, plastids, and mitochondria, evolved through the serial acquisition of endosymbionts by a host cell. These events were accompanied by gene transfer from the symbionts to the host, resulting in most of the organellar proteins being encoded in the cell nuclear genome and trafficked into the organelle via a series of translocation complexes. Much of what is known about organelle protein translocation mechanisms is based on studies performed in common model organisms; e.g., yeast and humans or Arabidopsis. However, studies performed in divergent organisms are gradually accumulating. These studies provide insights into universally conserved traits, while discovering traits that are specific to organisms or clades. Apicomplexan parasites feature two organelles of endosymbiotic origin: a secondary plastid named the apicoplast and a mitochondrion. In the context of the diseases caused by apicomplexan parasites, the essential roles and divergent features of both organelles make them prime targets for drug discovery. This potential and the amenability of the apicomplexan Toxoplasma gondii to genetic manipulation motivated research about the mechanisms controlling both organelles’ biogenesis. Here we provide an overview of what is known about apicomplexan organelle protein import. We focus on work done mainly in T. gondii and provide a comparison to model organisms

Cybersquatting: The Latest Challenge in Federal Trademark Protection

The explosion in Internet technology in the past decade has drawn the Lanham Act into the realm of electronic commerce. Trademark owners seeking to register domain names have recently found themselves entwined in a number of disputes, such as disputes involving claims to multiple domain names and disputes over whether the domain name registration system is fairly administered. One important legal issue that has recently come to the fore is over the practice of cybersquatting. Today, courts must contend with the cybersquatter, a speculator who reserves trademarks as Internet domain names for the sole purpose of selling or licensing them back to trademark owners willing to pay a considerable price for their use. Complicating matters, the most potent weapons in the Government\u27s anticybersquatting arsenal--the Anticybersquatting Consumer Protection Act (ACPA) and Federal Trademark Dilution Act (FTDA)--each give rise to grave constitutional concerns

Cybersquatting: The Latest Challenge in Federal Trademark Protection

The explosion in Internet technology in the past decade has drawn the Lanham Act into the realm of electronic commerce. Trademark owners seeking to register domain names have recently found themselves entwined in a number of disputes, such as disputes involving claims to multiple domain names and disputes over whether the domain name registration system is fairly administered. One important legal issue that has recently come to the fore is over the practice of cybersquatting. Today, courts must contend with the cybersquatter, a speculator who reserves trademarks as Internet domain names for the sole purpose of selling or licensing them back to trademark owners willing to pay a considerable price for their use. Complicating matters, the most potent weapons in the Government\u27s anticybersquatting arsenal--the Anticybersquatting Consumer Protection Act (ACPA) and Federal Trademark Dilution Act (FTDA)--each give rise to grave constitutional concerns

Does Glutamine Supplementation Contribute to the Incidence of Diarrhea in Ventaltor Dependent Patients?

In this project we investigated the incidence of diarrhea and its possible causes in ventilator dependent patients in the intensive care unit (ICU) at McKay-Dee Hospital. Chronic diarrhea has been a long time problem in the ICU, but the etiology has never been fully explored. High dose antibiotic therapy has been thought to be a potential risk factor. Another proposed risk has been the use of glutamine, a conditionally essential amino acid contained in some enteral products. Glutamine is commonly used in feeding critically ill patients because of its immune enhancing properties. Currently, we have not established a correlation between the use of glutamine and the incidence of diarrhea. Data obtained in this study, however, suggests that a correlation exists with high-dose antibiotic therapy. Future application of this research could lead to standard protocols in treatment of diarrhea in the ICU. Such protocols might include all patients administered high dose antibiotic therapy be given a probiotic supplement to prevent diarrhea. Also, if further evidence is found between glutamine supplementation and increased risk of diarrhea, discontinuing or reducing supplementation could be considered an alternative measure