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Outcomes after pneumonectomy versus limited lung resection in adults with traumatic lung injury.
Pneumonectomy after traumatic lung injury (TLI) is associated with shock, increased pulmonary vascular resistance, and eventual right ventricular failure. Historically, trauma pneumonectomy (TP) mortality rates ranged between 53 and 100%. It is unclear if contemporary mortality rates have improved. Therefore, we evaluated outcomes associated with TP and limited lung resections (LLR) (i.e., lobectomy and segmentectomy) and aimed to identify predictors of mortality, hypothesizing that TP is associated with greater mortality versus LLR. We queried the Trauma Quality Improvement Program (2010-2016) and performed a multivariable logistic regression to determine the independent predictors of mortality in TLI patients undergoing TP versus LLR. TLI occurred in 287,276 patients. Of these, 889 required lung resection with 758 (85.3%) undergoing LLR and 131 (14.7%) undergoing TP. Patients undergoing TP had a higher median injury severity score (26.0 vs. 24.5, p = 0.03) but no difference in initial median systolic blood pressure (109 vs. 107 mmHg, p = 0.92) compared to LLR. Mortality was significantly higher for TP compared to LLR (64.9% vs 27.2%, p < 0.001). The strongest independent predictor for mortality was undergoing TP versus LLR (OR 4.89, CI 3.18-7.54, p < 0.001). TP continues to be associated with a higher mortality compared to LLR. Furthermore, TP is independently associated with a fivefold increased risk of mortality compared to LLR. Future investigations should focus on identifying parameters or treatment modalities that improve survivability after TP. We recommend that surgeons reserve TP as a last-resort management given the continued high morbidity and mortality associated with this procedure
BPS black holes, quantum attractor flows and automorphic forms
We propose a program for counting microstates of four-dimensional BPS black
holes in N >= 2 supergravities with symmetric-space valued scalars by
exploiting the symmetries of timelike reduction to three dimensions. Inspired
by the equivalence between the four dimensional attractor flow and geodesic
flow on the three-dimensional scalar manifold, we radially quantize stationary,
spherically symmetric BPS geometries. Connections between the topological
string amplitude, attractor wave function, the Ooguri-Strominger-Vafa
conjecture and the theory of automorphic forms suggest that black hole
degeneracies are counted by Fourier coefficients of modular forms for the
three-dimensional U-duality group, associated to special "unipotent"
representations which appear in the supersymmetric Hilbert space of the quantum
attractor flow.Comment: 9 pages, revtex; v2: references added and typos correcte
Black Hole Attractors and the Topological String
A simple relationship of the form Z_BH = |Z_top|^2 is conjectured, where Z_BH
is a supersymmetric partition function for a four-dimensional BPS black hole in
a Calabi-Yau compactification of Type II superstring theory and Z_top is a
second-quantized topological string partition function evaluated at the
attractor point in moduli space associated to the black hole charges. Evidence
for the conjecture in a perturbation expansion about large graviphoton charge
is given. The microcanonical ensemble of BPS black holes can be viewed as the
Wigner function associated to the wavefunction defined by the topological
string partition function.Comment: 32 pages, harvma
Epigenetic aging signatures in mice livers are slowed by dwarfism, calorie restriction and rapamycin treatment
Background: Global but predictable changes impact the DNA methylome as we age, acting as a type of molecular
clock. This clock can be hastened by conditions that decrease lifespan, raising the question of whether it can also
be slowed, for example, by conditions that increase lifespan. Mice are particularly appealing organisms for studies of
mammalian aging; however, epigenetic clocks have thus far been formulated only in humans.
Results: We first examined whether mice and humans experience similar patterns of change in the methylome with
age. We found moderate conservation of CpG sites for which methylation is altered with age, with both species
showing an increase in methylome disorder during aging. Based on this analysis, we formulated an epigenetic-aging
model in mice using the liver methylomes of 107 mice from 0.2 to 26.0 months old. To examine whether epigenetic
aging signatures are slowed by longevity-promoting interventions, we analyzed 28 additional methylomes from mice
subjected to lifespan-extending conditions, including Prop1df/df dwarfism, calorie restriction or dietary rapamycin. We
found that mice treated with these lifespan-extending interventions were significantly younger in epigenetic age than
their untreated, wild-type age-matched controls.
Conclusions: This study shows that lifespan-extending conditions can slow molecular changes associated with an
epigenetic clock in mice livers
Measurement-based quantum computation in a 2D phase of matter
Recently it has been shown that the non-local correlations needed for
measurement based quantum computation (MBQC) can be revealed in the ground
state of the Affleck-Kennedy-Lieb-Tasaki (AKLT) model involving nearest
neighbor spin-3/2 interactions on a honeycomb lattice. This state is not
singular but resides in the disordered phase of ground states of a large family
of Hamiltonians characterized by short-range-correlated valence bond solid
states. By applying local filtering and adaptive single particle measurements
we show that most states in the disordered phase can be reduced to a graph of
correlated qubits that is a scalable resource for MBQC. At the transition
between the disordered and Neel ordered phases we find a transition from
universal to non-universal states as witnessed by the scaling of percolation in
the reduced graph state.Comment: 8 pages, 6 figures, comments welcome. v2: published versio
Electrophysiological Signatures of Spatial Boundaries in the Human Subiculum.
Environmental boundaries play a crucial role in spatial navigation and memory across a wide range of distantly related species. In rodents, boundary representations have been identified at the single-cell level in the subiculum and entorhinal cortex of the hippocampal formation. Although studies of hippocampal function and spatial behavior suggest that similar representations might exist in humans, boundary-related neural activity has not been identified electrophysiologically in humans until now. To address this gap in the literature, we analyzed intracranial recordings from the hippocampal formation of surgical epilepsy patients (of both sexes) while they performed a virtual spatial navigation task and compared the power in three frequency bands (1-4, 4-10, and 30-90 Hz) for target locations near and far from the environmental boundaries. Our results suggest that encoding locations near boundaries elicited stronger theta oscillations than for target locations near the center of the environment and that this difference cannot be explained by variables such as trial length, speed, movement, or performance. These findings provide direct evidence of boundary-dependent neural activity localized in humans to the subiculum, the homolog of the hippocampal subregion in which most boundary cells are found in rodents, and indicate that this system can represent attended locations that rather than the position of one\u27s own body
Topological wave functions and heat equations
It is generally known that the holomorphic anomaly equations in topological
string theory reflect the quantum mechanical nature of the topological string
partition function. We present two new results which make this assertion more
precise: (i) we give a new, purely holomorphic version of the holomorphic
anomaly equations, clarifying their relation to the heat equation satisfied by
the Jacobi theta series; (ii) in cases where the moduli space is a Hermitian
symmetric tube domain , we show that the general solution of the anomaly
equations is a matrix element \IP{\Psi | g | \Omega} of the
Schr\"odinger-Weil representation of a Heisenberg extension of , between an
arbitrary state and a particular vacuum state .
Based on these results, we speculate on the existence of a one-parameter
generalization of the usual topological amplitude, which in symmetric cases
transforms in the smallest unitary representation of the duality group in
three dimensions, and on its relations to hypermultiplet couplings, nonabelian
Donaldson-Thomas theory and black hole degeneracies.Comment: 50 pages; v2: small typos fixed, references added; v3: cosmetic
changes, published version; v4: typos fixed, small clarification adde
Exposure of U.S. National Parks to land use and climate change 1900-2100
Many protected areas may not be adequately safeguarding biodiversity from human activities on surrounding lands and global change. The magnitude of such change agents and the sensitivity of ecosystems to these agents vary among protected areas. Thus, there is a need to assess vulnerability across networks of protected areas to determine those most at risk and to lay the basis for developing effective adaptation strategies. We conducted an assessment of exposure of U.S. National Parks to climate and land use change and consequences for vegetation communities. We first defined park protected-area centered ecosystems (PACEs) based on ecological principles. We then drew on existing land use, invasive species, climate, and biome data sets and models to quantify exposure of PACEs from 1900 through 2100. Most PACEs experienced substantial change over the 20th century (.740% average increase in housing density since 1940, 13% of vascular plants are presently nonnative, temperature increase of 18C/100 yr since 1895 in 80% of PACEs), and projections suggest that many of these trends will continue at similar or increasingly greater rates (255% increase in housing density by 2100, temperature increase of 2.58–4.58C/100 yr, 30% of PACE areas may lose their current biomes by 2030). In the coming century, housing densities are projected to increase in PACEs at about 82% of the rate of since 1940. The rate of climate warming in the coming century is projected to be 2.5–5.8 times higher than that measured in the past century. Underlying these averages, exposure of individual park PACEs to change agents differ in important ways. For example, parks such as Great Smoky Mountains exhibit high land use and low climate exposure, others such as Great Sand Dunes exhibit low land use and high climate exposure, and a few such as Point Reyes exhibit high exposure on both axes. The cumulative and synergistic effects of such changes in land use, invasives, and climate are expected to dramatically impact ecosystem function and biodiversity in national parks. These results are foundational to developing effective adaptation strategies and suggest policies to better safeguard parks under broad-scale environmental change
Clinician Recommendations and Perceptions of Factors Associated With Ankle Brace Use
Little information is available regarding the ankle braces orthopaedic sports medicine clinicians recommend or clinicians’ concerns that may influence their decisions to recommend use of an ankle brace
Non-Singular Solutions for S-branes
Exact, non-singular, time-dependent solutions of Maxwell-Einstein gravity
with and without dilatons are constructed by double Wick rotating a variety of
static, axisymmetric solutions. This procedure transforms arrays of charged or
neutral black holes into s-brane (spacelike brane) solutions, i.e. extended,
short-lived spacelike defects. Along the way, new static solutions
corresponding to arrays of alternating-charge Reissner-Nordstrom black holes,
as well as their dilatonic generalizations, are found. Their double Wick
rotation yields s-brane solutions which are periodic in imaginary time and
potential large-N duals for the creation/decay of unstable D-branes in string
theory.Comment: 21 pages, 3 figure
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