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Follicular occlusion triad: an isotopic response or adverse effect of rituximab?
Follicular occlusion triad is a symptom complex of three conditions with a similar pathophysiology including hidradenitis suppurativa (HS), dissecting cellulitis of the scalp, and acne conglobata. Although the exact pathogenesis of the triad is unknown, it appears to be related to follicular occlusion in areas with apocrine glands. Wolf isotopic response refers to the occurrence of a new dermatosis at the site of another, unrelated, previously healed dermatosis. We present a 26-year-old man with a history of pemphigus foliaceus (PF) who developed large draining nodules with scarring and sinus tracts, compatible with follicular occlusion triad, preferentially at areas previously affected by PF thirteen months after treatment with rituximab. To the authors' knowledge there are no reported cases of follicular occlusion triad or HS manifesting as an isotopic response. However, one member of the triad, HS, has been reported to occur infrequently following the use of biologic agents such as adalimumab, infliximab, tocilizumab, and rituximab for chronic immune-mediated inflammatory diseases (psoriasis, Crohn disease, rheumatoid arthritis, and ankylosing spondylitis)
Transport properties in antiferromagnetic quantum Griffiths phases
We study the electrical resistivity in the quantum Griffiths phase associated
with the antiferromagnetic quantum phase transition in a metal. The resistivity
is calculated by means of the semi-classical Boltzmann equation. We show that
the scattering of electrons by locally ordered rare regions leads to a singular
temperature dependence. The rare-region contribution to the resistivity varies
as with temperature where the is the usual Griffiths
exponent which takes the value zero at the critical point and increases with
distance from criticality. We find similar singular contributions to other
transport properties such as thermal resistivity, thermopower and the Peltier
coefficient. We also compare our results with existing experimental data and
suggest new experiments.Comment: 4 pages, 1 figur
Fair Equality of Opportunity Critically Reexamined: The Family and the Sustainability of Health Care Systems
A complex interaction of ideological, financial, social, and moral
factors makes the financial sustainability of health care systems a
challenge across the world. One difficulty is that some of the moral
commitments of some health care systems collide with reality. In
particular, commitments to equality in access to health care and
to fair equality of opportunity undergird an unachievable promise,
namely, to provide all with the best of basic health care. In addition,
commitments to fair equality of opportunity are in tension with the
existence of families, because families are aimed at advantaging
their own members in preference to others. Because the social-democratic
state is committed to fair equality of opportunity, it offers
a web of publicly funded entitlements that make it easier for persons
to exit the family and to have children outside of marriage.
In the United States, in 2008, 41% of children were born outside of
wedlock, whereas, in 1940, the percentage was only 3.8%, and in
1960, 5%, with the further consequence that the social and financial
capital generated through families, which aids in supporting
health care in families, is diminished. In order to explore the challenge
of creating a sustainable health care system that also supports
the traditional family, the claims made for fair equality of opportunity
in health care are critically reconsidered. This is done by
engaging the expository device of John Rawls's original position, but
with a thin theory of the good that is substantively different from
that of Rawls, one that supports a health care system built around
significant copayments, financial counseling, and compulsory savings,
with a special focus on enhancing the financial and social
capital of the family. This radical recasting of Rawls, which draws
inspiration from Singapore, is undertaken as a heuristic to aid in articulating an approach to health care allocation that can lead
past the difficulties of social-democratic policy
Neural signatures of cognitive flexibility and reward sensitivity following nicotinic receptor stimulation in dependent smokers : a randomized trial
IMPORTANCE Withdrawal from nicotine is an important contributor to smoking relapse. Understanding how reward-based decision making is affected by abstinence and by pharmacotherapies such as nicotine replacement therapy and varenicline tartrate may aid cessation treatment.
OBJECTIVE To independently assess the effects of nicotine dependence and stimulation of the nicotinic acetylcholine receptor on the ability to interpret valence information (reward sensitivity) and subsequently alter behavior as reward contingencies change (cognitive flexibility) in a probabilistic reversal learning task.
DESIGN, SETTING, AND PARTICIPANTS Nicotine-dependent smokers and nonsmokers completed a probabilistic reversal learning task during acquisition of functional magnetic resonance imaging (fMRI) in a 2-drug, double-blind placebo-controlled crossover design conducted from January 21, 2009, to September 29, 2011. Smokers were abstinent from cigarette smoking for 12 hours for all sessions. In a fully Latin square fashion, participants in both groups underwent MRI twice while receiving varenicline and twice while receiving a placebo pill, wearing either a nicotine or a placebo patch. Imaging analysis was performed from June 15, 2015, to August 10, 2016.
MAIN OUTCOME AND MEASURES A well-established computational model captured effects of smoking status and administration of nicotine and varenicline on probabilistic reversal learning choice behavior. Neural effects of smoking status, nicotine, and varenicline were tested for on MRI contrasts that captured reward sensitivity and cognitive flexibility.
RESULTS The study included 24 nicotine-dependent smokers (12 women and 12 men; mean [SD] age, 35.8 [9.9] years) and 20 nonsmokers (10 women and 10 men; mean [SD] age, 30.4 [7.2] years). Computational modeling indicated that abstinent smokers were biased toward response shifting and that their decisions were less sensitive to the available evidence, suggesting increased impulsivity during withdrawal. These behavioral impairments were mitigated with nicotine and varenicline. Similarly, decreased mesocorticolimbic activity associated with cognitive flexibility in abstinent smokers was restored to the level of nonsmokers following stimulation of nicotinic acetylcholine receptors (familywise error-corrected P<.05). Conversely, neural signatures of decreased reward sensitivity in smokers (vs nonsmokers; familywise error-corrected P<.05) in the dorsal striatum and anterior cingulate cortex were not mitigated by nicotine or varenicline.
CONCLUSIONS AND RELEVANCE There was a double dissociation between the effects of chronic nicotine dependence on neural representations of reward sensitivity and acute effects of stimulation of nicotinic acetylcholine receptors on behavioral and neural signatures of cognitive flexibility in smokers. These chronic and acute pharmacologic effects were observed in overlapping mesocorticolimbic regions, suggesting that available pharmacotherapies may alleviate deficits in the same circuitry for certain mental computations but not for others
Non-Fermi-liquid behavior in Ce(RuFe)Ge: cause and effect
We present inelastic neutron scattering measurements on the intermetallic
compounds Ce(RuFe)Ge (=0.65, 0.76 and 0.87). These
compounds represent samples in a magnetically ordered phase, at a quantum
critical point and in the heavy-fermion phase, respectively. We show that at
high temperatures the three compositions have the identical response of a local
moment system. However, at low temperatures the spin fluctuations in the
critical composition are given by non-Fermi-liquid dynamics, while the spin
fluctuations in the heavy fermion system show a simple exponential decay in
time. In both compositions, the lifetime of the fluctuations is determined
solely by the distance to the quantum critical point. We discuss the
implications of these observations regarding the possible origins of
non-Fermi-liquid behavior in this system.Comment: 4 figures, submitted to PR
Electrodynamic Radiation Reaction and General Relativity
We argue that the well-known problem of the instabilities associated with the
self-forces (radiation reaction forces) in classical electrodynamics are
possibly stabilized by the introduction of gravitational forces via general
relativity
Filling gaps in seed germination and species selection: work in progress for dryland restoration in Argentina
Los practicantes de la restauración y rehabilitación ecológica (RRE) carecen de información completa sobre los tratamientos pregerminativos más efectivos para promover la germinación de plantas nativas de regiones áridas y semiáridas, y sobre la supervivencia y crecimiento de estas especies a campo. Aquí informamos resultados del enfoque “estrategias profesionales inteligentes” para evaluar la germinación de especies del Monte Austral, una región árida del sur de Argentina. Nuestros objetivos fueron probar una pequeña cantidad de tratamientos pregerminativos que son efectivos en otras regiones áridas y evaluar los resultados de germinación de 16 especies en comparación con la información existente sobre su desempeño a campo. Este enfoque demostró ser altamente efectivo dado que, de las 16 especies de arbustos evaluadas, 11 mostraron tasas de germinación adecuadas para RRE (es decir, más del 50%). Solo cuatro especies alcanzaron altas tasas de supervivencia y altos valores de cobertura vegetal en las plantaciones, y otras cuatro mostraron altas tasas de supervivencia, pero la cobertura vegetal fue baja o no se evaluó. Argumentamos que sería estratégico adoptar este modelo, que incluye obtener y comparar información sobre la germinación de semillas y el desempeño de las mismas especies a campo, para la selección de especies en RRE.Ecological restoration and rehabilitation (ERR) practitioners lack comprehensive information on the most effective seed dormancy alleviation treatments to enhance germination of native plants from arid and semiarid regions, as well as on survival and growth rates of these species in the field. In this paper we report on the results of a “professional intelligent tinkering” approach to assess seed germination of species from the Monte Austral, an arid region in southern Argentina. We aim to test a small number of seed dormancy alleviation treatments reported to be effective in other arid regions, and to assess germination results for 16 species against existing information on their performance in the field. This approach proved to be highly effective given that, out of the 16 shrub species evaluated, 11 showed germination rates suitable for ERR (i.e., over 50%). Only four species attained both high survival rates and plant cover values in outplantings, while four other species showed high survival rates but their plant cover values were low or not assessed. We argue that this approach, which involves obtaining and comparing data on seed germination rate with performance of the same species in the field, would be strategic for species selection in ERR.Fil: Rodriguez Araujo, María Emilia. Universidad Nacional del Comahue. Facultad de Ciencias del Ambiente y la Salud. Laboratorio de Rehabilitación y Restauración de Ecosistemas Áridos y Semiáridos Degradados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Confluencia; ArgentinaFil: Pérez, Daniel Roberto. Universidad Nacional del Comahue. Facultad de Ciencias del Ambiente y la Salud. Laboratorio de Rehabilitación y Restauración de Ecosistemas Áridos y Semiáridos Degradados; ArgentinaFil: Aronson, James. Missouri Botanical Garden; Estados Unidos. Ecohealth Network; Estados UnidosFil: Cross, Adam T.. Ecohealth Network; Estados Unidos. Curtin University; Australi
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