33 research outputs found
Superconformal Gravity And The Topology Of Diffeomorphism Groups
Twisted four-dimensional supersymmetric Yang-Mills theory famously gives a
useful point of view on the Donaldson and Seiberg-Witten invariants of
four-manifolds. In this paper we generalize the construction to include a path
integral formulation of generalizations of Donaldson invariants for smooth
families of four-manifolds. Mathematically these are equivariant cohomology
classes for the action of the oriented diffeomorphism group on the space of
metrics on the manifold. In principle these cohomology classes should contain
nontrivial information about the topology of the diffeomorphism group of the
four-manifold. We show that the invariants may be interpreted as the standard
topologically twisted path integral of four-dimensional
supersymmetric Yang-Mills coupled to topologically twisted background fields of
conformal supergravity.Comment: 79 pages + appendices = 166 pages; 1 figure; Hyperlinks fixe
Necdin Protects Embryonic Motoneurons from Programmed Cell Death
NECDIN belongs to the type II Melanoma Associated Antigen Gene Expression gene family and is located in the Prader-Willi Syndrome (PWS) critical region. Necdin-deficient mice develop symptoms of PWS, including a sensory and motor deficit. However, the mechanisms underlying the motor deficit remain elusive. Here, we show that the genetic ablation of Necdin, whose expression is restricted to post-mitotic neurons in the spinal cord during development, leads to a loss of 31% of specified motoneurons. The increased neuronal loss occurs during the period of naturally-occurring cell death and is not confined to specific pools of motoneurons. To better understand the role of Necdin during the period of programmed cell death of motoneurons we used embryonic spinal cord explants and primary motoneuron cultures from Necdin-deficient mice. Interestingly, while Necdin-deficient motoneurons present the same survival response to neurotrophic factors, we demonstrate that deletion of Necdin leads to an increased susceptibility of motoneurons to neurotrophic factor deprivation. We show that by neutralizing TNFα this increased susceptibility of Necdin-deficient motoneurons to trophic factor deprivation can be reduced to the normal level. We propose that Necdin is implicated through the TNF-receptor 1 pathway in the developmental death of motoneurons
New Works By Furman Composers
Live performance of new compositions by students enrolled in Furman\u27s Composition Seminar. Mark Kilstofte, moderato
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Timely Economic Information for Washington Farmers, Number 53, 1946 June
Topics include general business outlook, wheat, dry field peas, fruit, truck crops, dairying, poultry and eggs, turkeys, livestock and feed, cost of producing the 1945 Washington Apple Crop, personality adjustment of rural children as related to economic land use clas
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Caregiving and Confidence to Avoid Hospitalization for Children with Medical Complexity.
OBJECTIVE: To test associations between parent-reported confidence to avoid hospitalization and caregiving strain, activation, and health-related quality of life (HRQOL). STUDY DESIGN: In this prospective cohort study, enrolled parents of children with medical complexity (n = 75) from 3 complex care programs received text messages (at random times every 2 weeks for 3 months) asking them to rate their confidence to avoid hospitalization in the next month. Low confidence, as measured on a 10-point Likert scale (1 = not confident; 10 = fully confident), was defined as a mean rating <5. Caregiving measures included the Caregiver Strain Questionnaire, Family Caregiver Activation in Transition (FCAT), and caregiver HRQOL (Medical Outcomes Study Short Form 12 [SF12]). Relationships between caregiving and confidence were assessed with a hierarchical logistic regression and classification and regression trees (CART) model. RESULTS: The parents were mostly mothers (77%) and were linguistically diverse (20% spoke Spanish as their primary language), and 18% had low confidence on average. Demographic and clinical variables had weaker associations with confidence. In regression models, low confidence was associated with higher caregiver strain (aOR, 3.52; 95% CI, 1.45-8.54). Better mental HRQOL was associated with lower likelihood of low confidence (aOR, 0.89; 95% CI, 0.80-0.97). In the CART model, higher strain similarly identified parents with lower confidence. In all models, low confidence was not associated with caregiver activation (FCAT) or physical HRQOL (SF12) scores. CONCLUSIONS: Parents of children with medical complexity with high strain and low mental HRQOL had low confidence in the range in which intervention to avoid hospitalization would be warranted. Future work could determine how adaptive interventions to improve confidence and prevent hospitalizations should account for strain and low mental HRQOL
Fifteen years of emergency medicine literature in Africa: A scoping review
Introduction: Emergency medicine (EM) throughout Africa exists in various stages of development. The number and types of scientific EM literature can serve as a proxy indicator of EM regional development and activity. The goal of this scoping review is a preliminary assessment of potential size and scope of available African EM literature published over 15 years. Methods: We searched five indexed international databases as well as non-indexed grey literature from 1999-2014 using key search terms including “Africa”, “emergency medicine”, “emergency medical services”, and “disaster.” Two trained physician reviewers independently assessed whether each article met one or more of five inclusion criteria, and discordant results were adjudicated by a senior reviewer. Articles were categorised by subject and country of origin. Publication number per country was normalised by 1,000,000 population. Results: Of 6091 identified articles, 633 (10.4%) were included. African publications increased 10-fold from 1999 to 2013 (9 to 94 articles, respectively). Western Africa had the highest number (212, 33.5%) per region. South Africa had the largest number of articles per country (171, 27.0%) followed by Nigeria, Kenya, and Ghana. 537 (84.8%) articles pertained to facility-based EM, 188 (29.7%) to out-of-hospital emergency medicine, and 109 (17.2%) to disaster medicine. Predominant content areas were epidemiology (374, 59.1%), EM systems (321, 50.7%) and clinical care (262, 41.4%). The most common study design was observational (479, 75.7%), with only 28 (4.4%) interventional studies. All-comers (382, 59.9%) and children (91, 14.1%) were the most commonly studied patient populations. Undifferentiated (313, 49.4%) and traumatic (180, 28.4%) complaints were most common. Conclusion: Our review revealed a considerable increase in the growth of African EM literature from 1999 to 2014. Overwhelmingly, articles were observational, studied all-comers, and focused on undifferentiated complaints. The articles discovered in this scoping review are reflective of the relatively immature and growing state of African EM. Keywords: Emergency medicine, EM, Emergency medical services, EMS, Africa, Scoping review, Literature revie
Copyright's Digital/Analog Divide
This Article shows how the substantive balance of copyright law has been
overshadowed online by the system of intermediary safe harbors enacted as
part of the Digital Millennium Copyright Act (“DMCA”) in 1998. The Internet
safe harbors and the system of notice-and-takedown fundamentally changed
the incentives of platforms, users, and rightsholders in relation to claims
of copyright infringement. These different incentives interact to yield a
functional balance of copyright online that diverges markedly from the
experience of copyright law in traditional media environments. This article
also explores a second divergence: the DMCA’s safe harbor system is being
superseded by private agreements between rightsholders and large commercial
Internet platforms made in the shadow of those safe harbors. These
agreements relate to automatic copyright filtering systems, such as
YouTube’s Content ID, that not only return platforms to their gatekeeping
role, but encode that role in algorithms and software.
The normative implications of these developments are contestable. Fair use
and other axioms of copyright law still nominally apply online; but in
practice, the safe harbors and private agreements made in the shadow of
those safe harbors are now far more important determinants of online
behavior than whether that conduct is, or is not, substantively in
compliance with copyright law. The diminished relevance of substantive
copyright law to online expression has benefits and costs that appear
fundamentally incommensurable. Compared to the offline world, online
platforms are typically more permissive of infringement, and more open to
new and unexpected speech and new forms of cultural participation. However,
speech on these platforms is also more vulnerable to over-reaching claims
by rightsholders. There is no easy metric for comparing the value of
non-infringing expression enabled by the safe harbors to that which has
been unjustifiably suppressed by misuse of the notice-and-takedown system.
Likewise, the harm that copyright infringement does to rightsholders is not
easy to calculate, nor is it easy to weigh against the many benefits of the
safe harbors.
DMCA-plus agreements raise additional considerations. Automatic copyright
enforcement systems have obvious advantages for both platforms and
rightsholders; they may also allow platforms to be more hospitable to
certain types of user content. However, automated enforcement systems may
also place an undue burden on fair use and other forms of non-infringing
speech. The design of copyright enforcement robots encodes a series of
policy choices made by platforms and rightsholders and, as a result,
subjects online speech and cultural participation to a new layer of private
ordering and private control. In the future, private interests, not public
policy will determine the conditions under which users get to participate
in online platforms that adopt these systems. In a world where
communication and expression is policed by copyright robots, the
substantive content of copyright law matters only to the extent that those
with power decide that it should matter.
Keywords: Copyright, DMCA, Infringement, Internet, Safe harbors,
Enforcement, Fair use, Automation, Algorithms, Robots