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The deterministic motions of clouds and turbulence, despite their chaotic nature, nonetheless follow simple statistical power-law scalings: a fractal dimension D relates individual cloud perimeters p to measurement resolution, and turbulent fluctuations scale with separation distance through the Hurst exponent ℌ. It remains uncertain whether atmospheric turbulence is best characterized by split isotropy that is three-dimensional with ℌ = 1/3 at small scales and two-dimensional with ℌ = 1 at large scales, or by wide-range anisotropic scaling with an intermediate value of ℌ. Here, we introduce an "ensemble fractal dimension" De – analogous to D – that relates the total cloud perimeter per domain area 풫 as seen from space to measurement resolution, and show theoretically how turbulent dimensionality and cloud edge geometry are linked through ℌ = De − 1. Observationally, by progressively coarsening the resolution of cloud mask arrays from various global satellite platforms and a numerical simulation of a tropical domain we find the scaling De ~ 5/3, or ℌ ~ 2/3, a value nearly consistent with a previously proposed "23/9D" anisotropic turbulent scaling. Remarkably, the same scaling links two "limiting case" estimates of 풫 evaluated at the planetary scale and the Kolmogorov microscale, as separated by 11 orders of magnitude, suggesting that cloud and turbulent behaviors are constrained by basic planetary parameters. [ABSTRACT FROM AUTHOR]

Cloud area distributions are a defining feature of Earth's radiative exchanges with outer space. Cloud perimeter distributions n (p) are also interesting because the shared interface between clouds and clear sky determines exchanges of buoyant energy and air. Here, we test using detailed model output and a wide range of satellite datasets a first-principles prediction that perimeter distributions follow a scale-invariant power law n (p) ∝ p-(1+β) , where the exponent β = 1 is evaluated for perimeters within moist isentropic atmospheric layers. In model analyses, the value of β is closely reproduced. In satellite data, β is remarkably robust to latitude, season, and land–ocean contrasts, which suggests that, at least statistically speaking, cloud perimeter distributions are determined more by atmospheric stability than Coriolis forces, surface temperature, or contrasts in aerosol loading between continental and marine environments. However, the satellite-measured value of β is found to be 1.26 ± 0.06 rather than β = 1. The reason for the discrepancy is unclear, but comparison with a model reproduction of the satellite perspective suggests that it may owe to cloud overlap. Satellite observations also show that scale invariance governs cloud areas for a range at least as large as ∼ 3 to ∼ 3 × 10 5 km 2 , and notably with a corresponding power law exponent close to unity. Many prior studies observed a much smaller range for power law behavior, and we argue this difference is due to inappropriate treatments of the statistics of clouds that are truncated by the edge of the measurement domain. [ABSTRACT FROM AUTHOR]

BACKGROUND Patients undergoing Mohs micrographic surgery (MMS) are given detailed wound care instructions to prevent postoperative complications. Previous studies have revealed low treatment adherence in general dermatology, but adherence to postoperative wound care and its potential association with poor surgical outcomes remain largely unstudied. OBJECTIVE To determine the frequency and causes of wound care nonadherence in patients who underwent MMS. MATERIALS AND METHODS A questionnaire containing a modified Eight-Item Morisky Medication Adherence Measure Scale was administered to Mohs patients at their 1 to 2 weeks postoperative visit. RESULTS Sixty-three patients were solicited and consented to completing the questionnaire. The average modified Eight-Item Morisky Medication Adherence Measure Scale score was 7.4 of 8, indicating high adherence. Old age and wound care assistance were associated with increased adherence. Factors contributing to nonadherence included feeling well, being too busy, wound care causing discomfort, and being with friends or family. One patient (1.6%) with high adherence developed an epidermal inclusion cyst within the scar. No other complications were observed. CONCLUSION Most MMS patients demonstrated high adherence to wound care instructions, and nonadherence was not associated with postoperative complications. [ABSTRACT FROM AUTHOR]

The effect of aerosols on the properties of clouds is a large source of uncertainty in predictions of weather and climate. These aerosol‐cloud interactions depend critically on the ability of aerosol particles to form cloud droplets. A challenge in modeling aerosol‐cloud interactions is the representation of interactions between turbulence and cloud microphysics. Turbulent mixing leads to small‐scale fluctuations in water vapor and temperature that are unresolved in large‐scale atmospheric models. To quantify the impact of turbulent fluctuations on cloud condensation nuclei (CCN) activation, we used a high‐resolution Large Eddy Simulation of a convective cloud chamber to drive particle‐based cloud microphysics simulations. We show small‐scale fluctuations strongly impact CCN activity. Once activated, the relatively long timescales of evaporation compared to fluctuations causes droplets to persist in subsaturated regions, which further increases droplet concentrations. Plain Language Summary: Increases in cloud droplet number concentrations from human emissions of aerosol particles modify cloud properties, which strongly impacts Earth's energy balance. Large Eddy Simulations and Earth System Models are used to quantify these aerosol‐cloud interactions, but the spatial and temporal resolution of these models is too coarse to represent the impact of turbulence at the smallest scales. In this study, we show that small‐scale turbulent fluctuations lead to cloud droplet formation even when air is, on average, subsaturated, which would be impossible in conventional models of cloud microphysics. Our findings suggest that models that neglect turbulent fluctuations in supersaturation will underestimate cloud condensation nuclei activity under specific supersaturation regimes, which will may lead to error in modeled cloud properties. Key Points: Small‐scale turbulence leads to variability in the supersaturation experienced by aerosol particles and cloud droplets within cloudsTurbulent fluctuations increase cloud droplet formation at low supersaturation levels in comparison with uniform environmental conditionsAtmospheric models that neglect supersaturation variability due to turbulence may underestimate the number concentration of cloud droplets [ABSTRACT FROM AUTHOR]

Globally, clouds are known to warm the climate system in the thermal infrared because they typically emit thermal radiation to space at effective temperatures lower than the combined cloud‐free atmosphere and surface. However, here we show that ∼40% of low‐level clouds over sea ice tend to cool the Arctic system at TOA and contribute to a radiative cooling of the Arctic winter climate by −2.3 Wm−2, or a ∼16% reduction over the infrared warming effect of all clouds during winter. Based on satellite observations, low‐level clouds residing in surface‐based temperature inversions emit more longwave radiation to space than would occur in cloudless skies. While these clouds are known to significantly warm the surface, they cool the Arctic climate system overall. Our results imply that accurately representing the cloud radiative effects unique to the Arctic could help to constrain the regional energy budget. Plain Language Summary: The Arctic has become emblematic of climate change, with rapid warming that is at least twice as fast as the rest of the planet. However, major uncertainties in our confidence to understand and predict Arctic climate persist, particularly regarding the radiative effects of clouds. Here we use satellite data to quantify the radiative effects of Arctic low‐level clouds, and find approximately 40% of low‐level clouds over sea ice tend to radiatively cool the Arctic climate system (Earth's surface and the atmosphere) in winter, rather than warm the climate system as is typical for most clouds in the thermal infrared regime. This cooling effect is governed by the widespread surface temperature inversions (layers in which temperature increases with altitude), which cap these low‐level clouds and allow more longwave radiation to escape from the Earth to space compared to clear skies. This finding reveals a fundamental, but overlooked, characteristic of cloud radiative effects in the wintertime Arctic and establishes a new perspective for understanding Arctic climate change. Key Points: A full range of radiative effects for Arctic wintertime low clouds over sea ice is investigatedAbout 40% of low clouds over sea ice tends to cool the Arctic at the top of the atmosphere in the polar nightThese low clouds with a cooling effect at the top of the atmosphere reside within frequent surface‐based temperature inversions [ABSTRACT FROM AUTHOR]

The article focuses on the importance of integrating business education into dermatology residency programs. Topics include the significance of understanding the healthcare ecosystem for medical providers, teaching fundamental business principles to residents to inform decision-making, and the need for a standardized dermatology-specific curriculum that covers coding, billing, insurance, and other business-related aspects.

This paper is the second in a series in which kilometer-scale-resolving observations from the Atmospheric Radiation Measurement Program and output from the University of California, Los Angeles/Colorado State University cloud-resolving model (CRM) are used to evaluate the single-column model (SCM) version of the National Centers for Environmental Prediction Global Forecast System model. Part I demonstrated that kilometer-scale cirrus properties analyzed by applying the SCM's assumptions about cloud vertical overlap and horizontal homogeneity to its profiles of cloud water/ice mixing ratio, cloud fraction, and snow flux differed from the cloud radar observations while the CRM simulation reproduced most of the observed cirrus properties. The present study evaluates, through a comparison with the CRM, the SCM's representation of detrainment from deep cumulus and ice-phase microphysics in an effort to better understand the findings of Part I. This study finds that, although the SCM's detrainment rate profile averaged over the entire simulation period is comparable to the CRM's, detrainment in the SCM is comparatively sporadic and vertically localized. Too much detrained ice is sublimated when first detrained. Snow formed from detrained cloud ice falls through too deep of a layer. These aspects of the SCM's parameterizations may explain many of the differences in the cirrus properties between the SCM and the observations (or between the SCM and the CRM), and suggest several possible improvements for the SCM: 1) allowing multiple coexisting cumulus cloud types as in the original Arakawa-Schubert scheme, 2) prognostically determining the stratiform cloud fraction, and 3) explicitly predicting the snow mixing ratio. These would allow better representation of the detrainment from deep convection, better coupling of the volume of detrained air with cloud fraction, and better representation of snow flux.

Abstract: Before using a fluid dynamics physically based wildfire model to study wildfire, validation is necessary and model results need to be systematically and objectively analyzed and compared to real [...]

This study describes and demonstrates a new method for identifying deficiencies in how cloud processes are represented in large-scale models. Kilometer-scale-resolving cloud radar observations and cloud-resolving model (CRM) simulations were used to evaluate the representation of cirrus clouds in the single-column model (SCM) version of the National Centers for Environmental Prediction Global Forecast System model for a 29-day period during June and July 1997 at the Atmospheric Radiation Measurement Program site in Oklahoma. To produce kilometer-scale cirrus statistics from the SCM results, synthetic subgrid-scale (SGS) cloud fields were generated using the SCM's cloud fraction and hydrometeor content profiles, and the SCM's cloud overlap and horizontal inhomogeneity assumptions. Three sets of SCM synthetic SGS cloud fields were analyzed. Two NOSNOW sets were produced in which clouds did not include snow; one set used random overlap, the other, maximum/random. In the SNOW set, clouds included snow and random overlap was used. The three sets were sampled in the same way as the cloud-radar-detected cloud fields and the CRM-simulated cloud fields. The mean cirrus cloud occurrence frequency for the SCM NOSNOW cloud fields agrees with the observed value as well as the CRM's does, while that for SCM SNOW cloud fields is only half that observed. In most aspects, the SCM's cirrus properties differ significantly from the cloud radar's and the CRM's, which generally agree. In comparison, there are too many physically thin SCM NOSNOW cirrus layers (most occupy only a single model layer) and too many physically thick SCM SNOW cirrus layers (most are thicker than 4 km). For the optically thin subset of cirrus layers, 1) the mean, mode, and median ice water path, and layer-mean ice water content (IWC) values for the SCM are significantly larger than the observed and CRM values; 2) the SCM layer-mean IWCs decrease with cloud physical thickness, opposite to the observations and CRM results; and 3) the range of layer-mean effective radii in the SCM thin cirrus is too narrow.

A study conducted to find out whether, cardiac-resynchronization therapy is more beneficial with or without an implantable defibrillator, is presented. According to the study, when combined with an implantable defibrillator, cardiac-resynchronization therapy reduces mortality significantly.

Cloud radar data collected at the Atmospheric Radiation Measurement (ARM) Program's Southern Great Plains site were used to evaluate the properties of cirrus clouds that occurred in a cloud-resolving model (CRM) simulation of the 29-day summer 1997 intensive observation period (IOP). The simulation was 'forced' by the large-scale advective temperature and water vapor tendencies, horizontal wind velocity, and turbulent surface fluxes observed at the Southern Great Plains site. The large-scale advective condensate tendency was not observed. The correlation of CRM cirrus amount with Geostationary Operational Environmental Satellite (GOES) high cloud amount was 0.70 for the subperiods during which cirrus formation and decay occurred primarily locally, but only 0.30 for the entire IOP. This suggests that neglecting condensate advection has a detrimental impact on the ability of a model (CRM or single-column model) to properly simulate cirrus cloud occurrence. The occurrence, vertical location, and thickness of cirrus cloud layers, as well as the bulk microphysical properties of thin cirrus cloud layers, were determined from the cloud radar measurements for June, July, and August 1997. The composite characteristics of cirrus clouds derived from this dataset are well suited for evaluating CRMs because of the close correspondence between the timescales and space scales resolved by the cloud radar measurements and by CRMs. The CRM results were sampled at eight grid columns spaced 64 km apart using the same definitions of cirrus and thin cirrus as the cloud radar dataset. The composite characteristics of cirrus clouds obtained from the CRM were then compared to those obtained from the cloud radar. Compared with the cloud radar observations, the CRM cirrus clouds occur at lower heights and with larger physical thicknesses. The ice water paths in the CRM's thin cirrus clouds are similar to those observed. However, the corresponding cloud-layer-mean ice water contents are significantly less than observed due to the CRM's larger cloud-layer thicknesses. The strong dependence of cirrus microphysical properties on layer-mean temperature and layer thickness as revealed by the observations is reproduced by the CRM. In addition, both the CRM and the observations show that the thin cirrus ice water path during large-scale ascent is only slightly greater than during no ascent or descent.

The single congestus case was set up to compare the Lagrangian and Eulerian microphysics methods in representing the cloud droplet size distribution (DSD) in a turbulent cloud environment. 2) The Lagrangian microphysics approach that offers a more natural way to study aerosol-cloud-precipitation interactions is becoming increasingly mature and is ready for simulations at subcloud and single-cloud scales. Keywords: Cloud microphysics; Clouds; Numerical analysis/modeling; Aerosol-cloud interaction EN Cloud microphysics Clouds Numerical analysis/modeling Aerosol-cloud interaction E1413 E1420 8 06/27/22 20220501 NES 220501 10th International Cloud Modeling Workshop B I What i : b More than 120 cloud modeling researchers participated in a virtual workshop to discuss recent progress in representing dynamics-microphysics interactions in numerical models and pathways to improve our understanding across a variety of scales. The case was simulated with four different idealized modeling setups: Cloud Model 1 (CM1; [3]) with two-moment NSSL microphysics ([25]), and Icosahedral Nonhydrostatic model (ICON; [43]) run in either 2D or 3D with two-moment bulk microphysics ([36]) or with McSnow Lagrangian microphysics ([1]). [Extracted from the article]

A microscale wildfire model, QES-Fire, that dynamically couples the fire front to microscale winds was developed using a simplified physics rate of spread (ROS) model, a kinematic plumerise model and a mass-consistent wind solver. The model is three-dimensional and couples fire heat fluxes to the wind field while being more computationally efficient than other coupled models. The plume-rise model calculates a potential velocity field scaled by the ROS model's fire heat flux. Distinct plumes are merged using a multiscale plume-merging methodology that can efficiently represent complex fire fronts. The plume velocity is then superimposed on the ambient winds and the wind solver enforces conservation of mass on the combined field, which is then fed into the ROS model and iterated on until convergence. QES-Fire's ability to represent plume rise is evaluated by comparing its results with those from an atmospheric large-eddy simulation (LES) model. Additionally, the model is compared with data from the FireFlux II field experiment. QES-Fire agrees well with both the LES and field experiment data, with domain-integrated buoyancy fluxes differing by less than 17% between LES and QES-Fire and less than a 10% difference in the ROS between QES-Fire and FireFlux II data. [ABSTRACT FROM AUTHOR]

Sweet syndrome (SS), also known as acute febrile neutrophilic dermatosis, is an uncommon skin eruption characterized by fever, leukocytosis, and tender erythematous papules, nodules, and plaques. Histopathologically, SS lesions are characterized by marked superficial papillary edema with a dense neutrophilic infiltrate. SS is known to demonstrate both the Koebner phenomenon and pathergy. The majority of reported cases of these phenomena occur following significant cutaneous injury (e.g., biopsies, burns) rather than minor trauma such as pressure and friction. Here, we present the first known reported case of SS koebnerization secondary to minor grooming‐related hair plucking. In addition, this is also the first reported case to our knowledge of SS with perifollicular involvement on histopathology. [ABSTRACT FROM AUTHOR]

[Figure: see text]. [ABSTRACT FROM AUTHOR]

A unique and sudden need for virtual medical visits created by the coronavirus disease 2019 (COVID-19) pandemic has led to an unprecedented expansion of telemedicine across nearly all medical specialties in the United States. In addition to providing essential medical services during the pandemic, telemedicine has the potential to expand health care access to underserved populations by eliminating traditional barriers to care such as transportation needs, distance from specialty providers, and approved time off from work. However, the literature regarding telehealth accessibility for low-income, non-English-speaking, and minority patients remains limited. Through a cross-sectional analysis comparing 2019 clinic visits with 2020 telehealth visits at the UMass Memorial Medical Center, we demonstrate specialty-specific changes in patient demographics, including a younger population, fewer non-English-speaking patients, and a relative preservation of minority, Medicaid, and Medicare patients among telehealth visits in comparison to clinic visits. We also demonstrate that nonsurgical specialties had significantly lower no-show rates and the greatest number of telehealth visits. Overall, our findings highlight the potential shortcomings of telemedicine in servicing non-English-speaking patients, while maintaining that it is an important tool with the potential to improve access to health care, particularly in nonprocedural specialties. [ABSTRACT FROM AUTHOR]