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Thiotepa hyperpigmentation preceding epidermal necrosis: malignant intertrigo misdiagnosed as Stevens-Johnson syndrome-toxic epidermal necrolysis overlap
Thiotepa is a common alkylating agent known to precipitate cutaneous reactions consistent with toxic erythema of chemotherapy, including erythema and hyperpigmentation. Herein, we describe an atypical case of malignant intertrigo involving preferential erythema and desquamation not only of skin folds but also of occluded areas after thiotepa-based conditioning. The diagnosis was complicated by concurrent stomatitis and oral petechiae in the setting of autologous stem cell transplant 11 days prior for diffuse large B-cell lymphoma. Histopathological examination from two cutaneous sites demonstrated epidermal dysmaturation and eccrine gland necrosis consistent with thiotepa-induced desquamation and not Stevens-Johnson syndrome or graft-versus-host-disease. Malignant intertrigo can present with extensive cutaneous involvement, as evidenced by our patient who had 25% body surface area affected. Mucosal involvement is common with most chemotherapeutic regimens and its presence should not deter the astute clinician from consideration of a diagnosis of toxic erythema of chemotherapy. No further interventions were needed and the patient healed spontaneously
Getting to know you: Accuracy and error in judgments of character
Character judgments play an important role in our everyday lives. However, decades of empirical research on trait attribution suggest that the cognitive processes that generate these judgments are prone to a number of biases and cognitive distortions. This gives rise to a skeptical worry about the epistemic foundations of everyday characterological beliefs that has deeply disturbing and alienating consequences. In this paper, I argue that this skeptical worry is misplaced: under the appropriate informational conditions, our everyday character-trait judgments are in fact quite trustworthy. I then propose a mindreading-based model of the socio-cognitive processes underlying trait attribution that explains both why these judgments are initially unreliable, and how they eventually become more accurate
Effects of Lightning on Trees: A Predictive Model Based on in situ Electrical Resistivity
The effects of lightning on trees range from catastrophic death to the absence of observable damage. Such differences may be predictable among tree species, and more generally among plant life history strategies and growth forms. We used fieldâcollected electrical resistivity data in temperate and tropical forests to model how the distribution of power from a lightning discharge varies with tree size and identity, and with the presence of lianas. Estimated heating density (heat generated per volume of tree tissue) and maximum power (maximum rate of heating) from a standardized lightning discharge differed 300% among tree species. Tree size and morphology also were important; the heating density of a hypothetical 10 m tall Alseis blackiana was 49 times greater than for a 30 m tall conspecific, and 127 times greater than for a 30 m tall Dipteryx panamensis. Lianas may protect trees from lightning by conducting electric current; estimated heating and maximum power were reduced by 60% (±7.1%) for trees with one liana and by 87% (±4.0%) for trees with three lianas. This study provides the first quantitative mechanism describing how differences among trees can influence lightningâtree interactions, and how lianas can serve as natural lightning rods for trees
The comparative biology of skeletal metastasis
Bone metastasis, a very common sequelae of cancer, is often associated with great morbidity. Understanding the biology of bone metastases may lead to therapeutic interventions to target the metastases. In addition to replacing bone marrow elements, the presence of tumour cells in bone modulates the normal bone remodelling process. Some tumours result in primarily osteolytic bone lesions, whereas others are associated with osteoblastic bone lesions. In either case, the resulting changes in the bone structure result in weakened bone that induces pain and is predisposed to fracture. The mechanisms through which cancer cells modulate bone remodelling are not clearly defined, but ongoing research using a variety of animal models will hopefully provide clues to prevent or slow the progress of bone metastases.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73390/1/j.1476-5829.2003.00023.x.pd
Impact of an improved neutrino energy estimate on outflows in neutron star merger simulations
Binary neutron star mergers are promising sources of gravitational waves for
ground-based detectors such as Advanced LIGO. Neutron-rich material ejected by
these mergers may also be the main source of r-process elements in the
Universe, while radioactive decays in the ejecta can power bright
electromagnetic post-merger signals. Neutrino-matter interactions play a
critical role in the evolution of the composition of the ejected material,
which significantly impacts the outcome of nucleosynthesis and the properties
of the associated electromagnetic signal. In this work, we present a simulation
of a binary neutron star merger using an improved method for estimating the
average neutrino energies in our energy-integrated neutrino transport scheme.
These energy estimates are obtained by evolving the neutrino number density in
addition to the neutrino energy and flux densities. We show that significant
changes are observed in the composition of the polar ejecta when comparing our
new results with earlier simulations in which the neutrino spectrum was assumed
to be the same everywhere in optically thin regions. In particular, we find
that material ejected in the polar regions is less neutron rich than previously
estimated. Our new estimates of the composition of the polar ejecta make it
more likely that the color and timescale of the electromagnetic signal depend
on the orientation of the binary with respect to an observer's line-of-sight.
These results also indicate that important observable properties of neutron
star mergers are sensitive to the neutrino energy spectrum, and may need to be
studied through simulations including a more accurate, energy-dependent
neutrino transport scheme.Comment: 19p, 17 figures, Accepted by Phys.Rev.
Evidence for quantum confinement in the photoluminescence of porous Si and SiGe
We have used anodization techniques to process porous surface regions in p-type Czochralski Si and in p-type Si0.85Ge0.15 epitaxial layers grown by molecular beam epitaxy. The SiGe layers were unrelaxed before processing. We have observed strong near-infrared and visible light emission from both systems. Analysis of the radiative and nonradiative recombination processes indicate that the emission is consistent with the decay of excitons localized in structures of one or zero dimensions
Adaptive Management and Quail Conservation on Rangelands in the American West
Adaptive management has been and is being practiced with the goal of sustaining populations of wild quails on large areas of rangelands in the American West. Because the current land use practices throughout most of the eastern two-thirds of the United States largely do not promote early-successional vegetation communities, rangelands contain the largest remaining blocks of contiguous (unfragmented) habitat for the northern bobwhite (Colinus virginianus) and the other 5 species of quails found in the western states. Many wildlife professionals on both private and public rangelands are practicing a diverse array of quail habitat and population management actions that could be considered a form of adaptive managementâan iterative process used to make decisions in the context of uncertainty. Though this âlearning by doingâ approach is not always formally labeled adaptive management, these wildlife professionals intuitively recognize the value of the process in sustaining populations of wild quails. We support our assertions about adaptive management with 4 case study examples of adaptive management projects that promote quail conservationâincluding quail huntingâon both private and public rangelands in the American West. By discussing these scenarios within an adaptive management framework, we hope to highlight current and future opportunities for adaptive management in quail conservation on rangelands and to discuss where adaptive management may be improved or no longer be appropriate
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