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Nathaniel Goldman,1,2 Joseph Han,3 Avery LaChance1 1Department of Dermatology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA; 2New York Medical College, School of Medicine, Valhalla, NY, USA; 3Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY, USACorrespondence: Avery LaChance, Connective Tissue Diseases Clinic, Health Policy and Advocacy, Department of Dermatology, Brigham and Women’s Hospital, Harvard Medical School, 221 Longwood Avenue, Boston, MA, 02215, USA, Tel +1 617-582-6060, Fax +1 617-532-6060, Email alachance@bwh.harvard.eduAbstract: The cutaneous features of autoimmune connective tissue disease pose a unique challenge to patients and clinicians managing these conditions. In this review, we outline the key elements of diagnosis and treatment of cutaneous lupus erythematosus, dermatomyositis, systemic sclerosis, and morphea. This article also aims to present an update on gold standard as well as new and emerging therapies for these conditions. Overall, dermatologists can play a key role in diagnosing and treating autoimmune connective tissue diseases and this review intends to provide an up-to-date toolkit to guide clinical dermatologists in this endeavor.Keywords: cutaneous lupus erythematosus, dermatomyositis, systemic sclerosis, morphea, eosinophilic fasciitis

In this work, we describe a toolbox to realize and probe synthetic axial gauge fields in engineered Weyl semimetals. These synthetic electromagnetic fields, which are sensitive to the chirality associated with Weyl nodes, emerge due to spatially and temporally dependent shifts of the corresponding Weyl momenta. First, we introduce two realistic models, inspired by recent cold-atom developments, which are particularly suitable for the exploration of these synthetic axial gauge fields. Second, we describe how to realize and measure the effects of such axial fields through center-ofmass observables, based on semiclassical equations of motion and exact numerical simulations. In particular, we suggest realistic protocols to reveal an axial Hall response due to the axial electric field E5, as well as axial cyclotron orbits and chiral pseudo-magnetic effect due to the axial magnetic field B5.

We use data from three rounds of the Mexican Family Life Survey to examine whether migrants in the United States returning to Mexico in the period 2005–2012 have worse health than those remaining in the United States. Despite extensive interest by demographers in health-related selection, this has been a neglected area of study in the literature on U.S.-Mexico migration, and the few results to date have been contradictory and inconclusive. Using five self-reported health variables collected while migrants resided in the United States and subsequent migration history, we find direct evidence of higher probabilities of return migration for Mexican migrants in poor health as well as lower probabilities of return for migrants with improving health. These findings are robust to the inclusion of potential confounders reflecting the migrants’ demographic characteristics, economic situation, family ties, and origin and destination characteristics. We anticipate that in the coming decade, health may become an even more salient issue in migrants’ decisions about returning to Mexico, given the recent expansion in access to health insurance in Mexico.

Although many studies have attempted to examine the consequences of Mexico-U.S. migration for Mexican immigrants' health, few have had adequate data to generate the appropriate comparisons. In this article, we use data from two waves of the Mexican Family Life Survey (MxFLS) to compare the health of current migrants from Mexico with those of earlier migrants and nonmigrants. Because the longitudinal data permit us to examine short-term changes in health status subsequent to the baseline survey for current migrants and for Mexican residents, as well as to control for the potential health selectivity of migrants, the results provide a clearer picture of the consequences of immigration for Mexican migrant health than have previous studies. Our findings demonstrate that current migrants are more likely to experience recent changes in health status-both improvements and declines-than either earlier migrants or nonmigrants. The net effect, however, is a decline in health for current migrants: compared with never migrants, the health of current migrants is much more likely to have declined in the year or two since migration and not significantly more likely to have improved. Thus, it appears that the migration process itself and/or the experiences of the immediate post-migration period detrimentally affect Mexican immigrants' health. © 2014 Population Association of America.

The availability of pulsed x rays on short timescales has opened up new avenues of research in the physics and chemistry of shocked materials. The continued installation of shock platforms such as gas guns and high power lasers placed at beamline x-ray facilities has advanced our knowledge of materials shocked to extreme conditions of pressure and temperature. In addition, theoretical advancements have made direct correspondence with high-pressure x-ray experiments more viable, increasing the predictive capability of these models. In this paper, we discuss both recent experimental results and the theory and modeling that has been developed to treat these complex situations. Finally, we discuss the impact that new platforms and increased beam time may have on the future direction of this field. [ABSTRACT FROM AUTHOR]

Background Early coronavirus disease 2019 (COVID-19) diagnosis prior to laboratory testing results is crucial for infection control in hospitals. Models exist predicting COVID-19 diagnosis, but significant concerns exist regarding methodology and generalizability. Aim To generate the first COVID-19 diagnosis risk score for use at the time of hospital admission using the TRIPOD (transparent reporting of a multivariable prediction model for individual prognosis or diagnosis) checklist. Design A multivariable diagnostic prediction model for COVID-19 using the TRIPOD checklist applied to a large single-centre retrospective observational study of patients with suspected COVID-19. Methods 581 individuals were admitted with suspected COVID-19; the majority had laboratory-confirmed COVID-19 (420/581, 72.2%). Retrospective collection was performed of electronic clinical records and pathology data. Results The final multivariable model demonstrated AUC 0.8535 (95% confidence interval 0.8121–0.8950). The final model used six clinical variables that are routinely available in most low and high-resource settings. Using a cut-off of 2, the derived risk score has a sensitivity of 78.1% and specificity of 86.8%. At COVID-19 prevalence of 10% the model has a negative predictive value (NPV) of 96.5%. Conclusions Our risk score is intended for diagnosis of COVID-19 in individuals admitted to hospital with suspected COVID-19. The score is the first developed for COVID-19 diagnosis using the TRIPOD checklist. It may be effective as a tool to rule out COVID-19 and function at different pandemic phases of variable COVID-19 prevalence. The simple score could be used by any healthcare worker to support hospital infection control prior to laboratory testing results. [ABSTRACT FROM AUTHOR]

Two polarizable six-dimensional water dimer intermolecular potential surfaces have been determined by fitting the distributed multipole ASP (anisotropic site potential) potential form to microwave, terahertz, and midinfrared cavity ringdown (D[sub 2]O)[sub 2] spectra via a rigorous calculation of the water dimer eigenstates with the PSSH (pseudo-spectral split Hamiltonian) method. The fitted potentials accurately reproduce most ground-state vibration-rotation-tunneling spectra and yield excellent second virial coefficients for both H[sub 2]O and D[sub 2]O. The calculated dimer structure and dipole moment are close to those determined from microwave spectroscopy and high level ab initio calculations, except that the O-O distance (2.952 Å) is significantly shorter than the currently accepted experimental value. The dimer binding energy (4.85 kcal/mol) is considerably smaller than the accepted experimental result, but in excellent agreement with recent theoretical results, as are the acceptor switching and donor-acceptor interchange tunneling barriers and the cyclic water trimer and tetramer structures and binding energies. [ABSTRACT FROM AUTHOR]

Résumé Introduction L’exposition au mercure métallique peut causer des intoxications accidentelles sévères dont l’expression clinique varie selon la voie d’intoxication, la dose, le délai et la durée d’exposition. Elle est devenue rare en France, mais il faut savoir l’évoquer et orienter l’anamnèse devant un tableau multisystémique sans explication claire. Cas clinique Une enfant de 12 ans a été hospitalisée pour toux, altération de l’état général, frissons, sueurs nocturnes, associées à un ralentissement psychomoteur et à des lésions cutanées évoluant depuis plusieurs semaines. L’examen clinique a révélé une tachycardie sinusale, une hypertension artérielle et une abolition des réflexes ostéotendineux. Les examens complémentaires se sont avérés normaux hormis une protéinurie glomérulaire sans insuffisance rénale. La mère a alors rapporté que l’enfant avait joué avec des billes de mercure trois mois auparavant. La suspicion d’intoxication a été confirmée par un dosage sanguin et urinaire et une ponction biopsie rénale retrouvant un aspect de glomérulonéphrite extramembraneuse avec dépôts d’IgG et de C3. L’intoxication par voie transdermique étant peu probable sur peau saine, l’enquête de l’Agence régionale de la santé a conclu à une intoxication chronique par inhalation du mercure renversé sur le sol au moment de l’exposition, aspiré puis rediffusé par l’aspirateur contaminé. L’évolution a été favorable en quelques semaines sous traitement chélateur par acide dimercaptosuccinique. Conclusion Le diagnostic d’intoxication au mercure doit être évoqué devant ce type d’atteinte multisystémique, afin d’intervenir rapidement et d’éviter des séquelles rénales et neurologiques irréversibles. Summary Introduction Exposure to metallic mercury can cause severe accidental intoxications in children, whose clinical symptoms can vary depending on the route of administration, the dose, as well as the time and duration of the exposure. It has become unusual in France, yet it must be considered when taking a patient's medical history in cases of multisystemic involvement without a clear explanation. Clinical case We report the case of a 12-year-old patient hospitalized because of a cough, poor general condition, chills, night sweats, psychomotor retardation, and skin lesions that had been developing for several weeks. The initial clinical examination also revealed sinus tachycardia, arterial hypertension, and abolition of osteotendinous reflexes. Complementary examination results were normal apart from a glomerular proteinuria without renal failure. When interviewing the mother, she reported that the child had played with mercury balls 3 months earlier. The suspicion of poisoning was confirmed by blood and urine analysis as well as renal biopsy showing an aspect of membranous glomerulonephritis with IgG and C3 depositions. An intoxication via a transdermal route being unlikely on healthy skin, the Regional Health Agency's survey concluded that chronic intoxication had occurred by inhalation of the mercury spread on the floor at the time of the exposure, which was then vacuum cleaned and released again by the contaminated vacuum cleaner. The patient's outcome was favorable within a few weeks after initiating DMSA chelation therapy. Conclusion Mercury poisoning should be considered in cases of a multisystemic disorder without clear explanation, in order to intervene quickly and thus prevent irreversible renal and neurological consequences. [ABSTRACT FROM AUTHOR]

The continuing debate among geneticists about using analysis of mitochondrial DNA (mtDNA) to investigate human origins has demonstrated that statistically reliable techniques for deducing genealogies are imperative. In 1987 researcher Allan Wilson and colleagues announced that mtDNA variation indicated that humanity's ancestor was probably an African woman who lived about 200,000 years ago. Wilson's group reached this conclusion by choosing the genealogical tree with the fewest changes as the parsimony criterion requires. However, other researchers dispute this result.

Sixty years ago, Karplus and Luttinger pointed out that quantum particles moving on a lattice could acquire an anomalous transverse velocity in response to a force, providing an explanation for the unusual Hall effect in ferromagnetic metals. A striking manifestation of this transverse transport was then revealed in the quantum Hall effect where the plateaux depicted by the Hall conductivity were attributed to a topological invariant characterizing the Bloch bands: the Chern number. Until now, topological transport associated with non-zero Chern numbers has only been observed in electronic systems. Here we use the transverse deflection of an atomic cloud in response to an optical gradient to measure the Chern number of artificially generated Hofstadter bands. These topological bands are very flat and thus constitute good candidates for the realization of fractional Chern insulators. Combining these deflection measurements with the determination of the band populations, we obtain an experimental value for the Chern number of the lowest band νexp = 0.99(5). This first Chern-number measurement in a non-electronic system is facilitated by an all-optical artificial gauge field scheme, generating uniform flux in optical superlattices. [ABSTRACT FROM AUTHOR]

We describe a scheme to engineer non-Abelian gauge potentials on a square optical lattice using laser-induced transitions. We emphasize the case of two-electron atoms, where the electronic ground state g is laser-coupled to a metastable state e within a state-dependent optical lattice. In this scheme, the alternating pattern of lattice sites hosting g and e states depicts a chequerboard structure, allowing for laser-assisted tunnelling along both spatial directions. In this configuration, the nuclear spin of the atoms can be viewed as a 'flavour' quantum number undergoing non-Abelian tunnelling along nearest-neighbour links. We show that this technique can be useful to simulate the equivalent of the Haldane quantum Hall model using cold atoms trapped in square optical lattices, offering an interesting route to realize Chern insulators. The emblematic Haldane model is particularly suited to investigate the physics of topological insulators, but requires, in its original form, complex hopping terms beyond nearest-neighbouring sites. In general, this drawback inhibits a direct realization with cold atoms, using standard laser-induced tunnelling techniques. We demonstrate that a simple mapping allows us to express this model in terms of matrix hopping operators that are defined on a standard square lattice. This mapping is investigated for two models that lead to anomalous quantum Hall phases. We discuss the practical implementation of such models, exploiting laser-induced tunnelling methods applied to the chequerboard optical lattice. [ABSTRACT FROM AUTHOR]

Ultracold fermions trapped in a honeycomb optical lattice constitute a versatile setup to experimentally realize the Haldane model (1988 Phys. Rev. Lett. 61 2015). In this system, a non-uniform synthetic magnetic flux can be engineered through laser-induced methods, explicitly breaking time-reversal symmetry. This potentially opens a bulk gap in the energy spectrum, which is associated with a non-trivial topological order, i.e. a non-zero Chern number. In this paper, we consider the possibility of producing and identifying such a robust Chern insulator in the laser-coupled honeycomb lattice. We explore a large parameter space spanned by experimentally controllable parameters and obtain a variety of phase diagrams, clearly identifying the accessible topologically non-trivial regimes. We discuss the signatures of Chern insulators in coldatom systems, considering available detection methods. We also highlight the existence of topological semi-metals in this system, which are gapless phases characterized by non-zero winding numbers, not present in Haldane's original model. [ABSTRACT FROM AUTHOR]

PURPOSE: Tracheotomy is one of the oldest surgical procedures known. There are multiple indications for tracheostomies. Operative complications have ranged between 5-40%. This manuscript describes our experience with 171 open tracheostomies at a major academic medical center. METHODS: A retrospective review of all patients' records who underwent an open tracheostomy by the Division of OMS between July 1, 2007 to December 31, 2010 was performed. Specific information including indication for procedure, age of patient, type and size of tracheostomy tube, and any post-operative complications were compiled. Based on the data gathered, statistical analysis was performed to establish incidence of complications and its correlation to the specific indication for the tracheostomy. Trends and outcome assessments were then determined. RESULTS: Median age for tracheostomy in the group was 36 (17-89). Majority of tracheostomies were performed in conjunction with head and neck oncologic procedures (51%). Complication rate was 4.1% (7 patients out of 171). CONCLUSION: Open tracheostomy is an extremely useful surgical procedure. If performed appropriately, it is associated with a low complication rate. [ABSTRACT FROM AUTHOR]

This study aimed to estimate the incidence of hospital transmission of influenza A subtype H1N1 [A(H1N1)], to identify high-risk areas for such transmission and to evaluate common characteristics of affected patients. In this single-centre retrospective cohort study, 10 patients met the criteria for hospital-acquired A(H1N1) infection over a three-month period. All affected patients required an escalation of their care and the mortality rate was 20%. Clinicians should be aware of the risk of nosocomial A(H1N1) infection that exists despite routine infection control measures and should consider additional control measures including vaccination of hospital inpatients and healthcare staff.Copyright © 2012 by Elsevier Inc. [ABSTRACT FROM AUTHOR]

We consider the combined effects of large spin-orbit couplings and a perpendicular magnetic field in a 2D honeycomb fermionic lattice. This system provides an elegant setup to generate versatile spin textures propagating along the edge of a sample. The spin-orbit coupling is shown to induce topological phase transitions between a helical quantum spin Hall phase and a chiral spin-imbalanced quantum Hall state. Besides, we find that the spin orientation of a single topological edge state can be tuned by a Rashba spin-orbit coupling, opening an interesting route towards quantum spin manipulation. We discuss the possible realization of our results using cold atoms trapped in optical lattices, where large synthetic magnetic fields and spin-orbit couplings can be engineered and finely tuned. In particular, this system would lead to the observation of a time-reversal symmetry-broken quantum spin Hall phase. [ABSTRACT FROM AUTHOR]

Dirac-Weyl fermions are massless relativistic particles with a well-defined helicity which arise in the context of high-energy physics. Here we propose a quantum simulation of these paradigmatic fermions using multicomponent ultracold atoms in a two-dimensional square optical lattice. We find that laser-assisted spin-dependent hopping, specifically tuned to the (2s + 1)-dimensional representations of the 5u(2) Lie algebra, directly leads to a regime where the emerging massless excitations correspond to Dirac-Weyl fermions with arbitrary pseudospin s. We show that this platform hosts two different phases: a semimetallic phase that occurs for half-integer s, and a metallic phase that contains a flat zero-energy band at integer s. These phases host a variety of interesting effects, such as a very rich anomalous quantum Hall effect and a remarkable multirefringent Klein tunneling. In addition, we show that these effects are directly related to the number of underlying Dirac-Weyl species and zero modes. [ABSTRACT FROM AUTHOR]

Socioeconomic status is generally associated with better health, but recent evidence suggests that this 'social gradient' in health is far from universal. This study examines whether social gradients in smoking and obesity in Mexico - a country in the midst of rapid socioeconomic change - conform to or diverge from results for richer countries. Using a nationally representative sample of 39,129 Mexican adults, we calculate the odds of smoking and of being obese by educational attainment and by household wealth. We conclude that socioeconomic determinants of smoking and obesity in Mexico are complex, with some flat gradients and some strong positive or negative gradients. Higher social status (education and assets) is associated with more smoking and less obesity for urban women. Higher status rural women also smoke more, but obesity for these women has a non-linear relationship to education. For urban men, higher asset levels (but not education) are associated with obesity, whereas education is protective of smoking. Higher status rural men with more assets are more likely to smoke and be obese. As household wealth, education and urbanisation continue to increase in Mexico, these patterns suggest potential targets for public health intervention now and in the future. [ABSTRACT FROM AUTHOR]

Ultracold Fermi gases trapped in honeycomb optical lattices provide an intriguing scenario, where relativistic quantum electrodynamics (QED) can be tested. Here, we generalize this system to non-Abelian QED, where massless Dirac fermions interact with effective non-Abelian gauge fields. We show how in this setup a variety of topological phase transitions occur, which arise due to massless fermion pair production events, as well as pair annihilation events of two kinds: spontaneous and strongly interacting induced. Moreover, such phase transitions can be controlled and characterized in optical lattice experiments. [ABSTRACT FROM AUTHOR]

We examined whether perceived social position predicted mental and physical health outcomes (depressive symptoms, cognitive impairment, mobility restrictions, and self-assessed health) in a prospective study based on a nationally representative sample of older persons in Taiwan. Cross-sectional and longitudinal models were used to demonstrate the relationship between perceived social position and health, as reported by participants in the Social Environment and Biomarkers of Aging Study in Taiwan (SEBAS). Lower perceived social position predicted declining health beyond what was accounted for by objective indicators of socioeconomic position. As predicted, the effect was substantially reduced for all health outcomes in the presence of controls for baseline health. After including these controls, perceived social position was significantly related only to depressive symptoms. The findings suggest that the strength of the association between perceived social position and health may have been overstated in cross-sectional studies. [ABSTRACT FROM AUTHOR]

We study the behaviour of hydrogen-bonded systems under high pressure and temperature. First principle calculations of formic acid under isotropic pressure up to 70 GPa reveal the existence of a polymerization phase around 20 GPa, in support of recent IR, Raman, and XRD experiments. In this phase, covalent bonding develops between molecules of the same chain through symmetrization of hydrogen bonds. We also performed molecular dynamics simulations of water at pressures up to 115 GPa and 2000 K. Along this isotherm, we are able to define three different phases. We observe a molecular fluid phase with superionic diffusion of the hydrogens for pressure 34-58 GPa. We report a transformation to a phase dominated by transient networks of symmetric O-H hydrogen bonds at 95-115 GPa. As in formic acid, the network can be attributed to the symmetrization of the hydrogen bond, similar to the ice VII-ice X transition. [ABSTRACT FROM AUTHOR]