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This study focuses on methods to estimate dry marine aerosol surface area (SA) from bulk optical measurements. Aerosol SA is used in many models' ice nucleating particle (INP) parameterizations, as well as influencing particle light scattering, hygroscopic growth, and reactivity, but direct observations are scarce in the Southern Ocean (SO). Two campaigns jointly conducted in austral summer 2018 provided co‐located measurements of aerosol SA from particle size distributions and lidar to evaluate SA estimation methods in this region. Mie theory calculations based on measured size distributions were used to test a proposed approximation for dry aerosol SA, which relies on estimating effective scattering efficiency (Q) as a function of Ångström exponent (å). For distributions with dry å < 1, Q = 2 was found to be a good approximation within ±50%, but for distributions with dry å > 1, an assumption of Q = 3 as in some prior studies underestimates dry aerosol SA by a factor of 2 or more. We propose a new relationship between dry å and Q, which can be used for −0.2 < å < 2, and suggest å = 0.8 as the cutoff between primary and secondary marine aerosol‐dominated distributions. Application of a published methodology to retrieve dry marine aerosol SA from lidar extinction profiles overestimated aerosol SA by a factor of 3–5 during these campaigns. Using Microtops aerosol optical thickness measurements, we derive alternative lidar conversion parameters from our observations, applicable to marine aerosol over the SO. Plain Language Summary: The Southern Ocean (SO) surrounding Antarctica is one of the few places where aerosol concentrations and composition are similar to pre‐industrial values. This makes data collected in this region important for improving and understanding climate model simulations. However, direct observations of aerosols are rare because of the remoteness, frequent storms, and high winds and waves common to the SO. In this study, we use some of these rare aerosol observations to test methods for estimating important aerosol quantities using other measurements that are easier to collect. The improvements presented here may increase the availability of key data for improving climate models by replacing rare measurements with ones that can be collected continuously and autonomously. Key Points: Methods to estimate dry marine aerosol surface area (SA) from bulk optical measurements were tested for the Southern Ocean regionA new relationship between effective scattering efficiency and dry Ångström exponent is proposed for nephelometer measurementsOverestimation of aerosol SA from previous methods is reduced by derivation of new lidar backscatter conversion parameters [ABSTRACT FROM AUTHOR]

Objectives: To determine the phenotypic and genotypic antibiotic susceptibility of Mycoplasma amphoriforme isolates recovered from patients in the UK and Denmark.Methods: Seven isolates of M. amphoriforme were examined for antimicrobial susceptibility to seven antibiotics using the microbroth dilution assay in line with the CLSI guidelines for mycoplasmas. Each isolate was additionally subjected to WGS to identify resistance-associated mutations. Based on the consensus sequences from the genomic data, PCR primers were designed, and tested, for the amplification of the QRDR within the parC gene.Results: Of the seven isolates investigated, four (57%) were resistant to moxifloxacin (0.5-1 mg/L) and levofloxacin (1-2 mg/L), compared with those that were susceptible (0.03-0.06 and 0.006 mg/L, respectively). Isolate H29 was resistant to five of the seven antibiotics tested: moxifloxacin, 0.5 mg/L; levofloxacin, 2 mg/L; azithromycin, 64 mg/L; erythromycin, 128 mg/L; and clindamycin, 64 mg/L. All isolates were susceptible to tetracycline (0.06 mg/L) and lefamulin (0.001-0.004 mg/L). Mutations from genomic data confirmed the presence of an S89F mutation within the ParC protein among all fluoroquinolone-resistant isolates and an A2059G mutation in the 23S rRNA gene in the macrolide- and lincosamide-resistant isolate H29.Conclusions: To the best of our knowledge, this is the first time where phenotypic and genotypic resistance data have been paired for M. amphoriforme confirming a correlation between the two. These data suggest the need for focused testing and resistance determination of isolates from high-risk patients given the backdrop of a high prevalence of antimicrobial resistance. [ABSTRACT FROM AUTHOR]

A new single step method is described for calculating the time of flight for a 3-D case by using a linear array. Computational cost of the method is higher than the 2-step method for a full volume beamforming, but it has allowed for a reduction of an order-of-magnitude if 3 planes are used for real-time visualization and the need for a temporary storage of beamformed data is removed.

Two adaptive spectral estimation techniques are analyzed for spectral Doppler ultrasound, where the purpose is to minimize the observation window required for estimating the spectrogram. The methods have provided quality of the estimated power spectral density (PSD) of the blood signal and the adaptive methods have displayed superior performance for short observation windows when compared with the averaged periodogram.

A minimum variance (MV) approach for near-field, adaptive beamforming of broadband data implemented in the frequency domain and providing a set of adapted, complex apodization weights for each frequency subband is reported. The performance of the MV is demonstrated by the simulation data for the frequency subband MV beamformer that has significantly increased in lateral resolution compared with DS (delay-and-sum).

The concentrations and sizes of smaller aerosols (radius smaller than 0.5 [micro]m) in the marine atmosphere vary owing to natural and anthropogenic factors. The concentrations and sizes of giant and ultragiant aerosols vary primarily due to wind-speed-dependent wave breaking. In climate models the formation of warm rain from marine stratocumulus clouds is usually parameterized based on the drops that form on the smaller aerosols. The present process study, using a stochastic Monte Carlo cloud model, shows that the variability of giant sea-salt aerosols and the variability of smaller aerosol cloud condensation nuclei are equally important in determining precipitation flux in marine stratocumulus. This strongly suggests that the effects of giant sea-salt aerosols should be included in the parameterization of warm rain formation in climate and other large-scale models. The above results are based on highly detailed calculations of droplet growth in an idealized marine stratocumulus cloud; the authors believe that other marine stratus cloud conditions may change the calculated rain rates but that the conclusions regarding the relative importance of small and giant aerosols are robust.

The article discusses a new approach, where in subband processing and the coded excitation are used for the estimation of blood flow in medical ultrasound. The technique is shown to be extremely beneficial, accurate and less time-consuming.

The design and performance of two new velocity estimators which could be used to find both axial and lateral velocity components is presented. The estimators tested on in vivo data from a transverse scan of the common carotid artery showed the potential of the vector velocity estimation method under in vivo conditions.

The design and implementation of a real-time delay-and-sum synthetic aperture beamformer which could parametrically describe the beamforming delay and apodization coefficients is presented. The beamformer architecture could be implemented in hardware and applied to assess the clinical relevance of the use of synthetic aperture in medical applications.

A study was conducted to demonstrate the performance of plane wave excitation (PWE) method and identify the best parameter set of the method when the object for the virtual scanning is a large blood vessel close to the skin surface. It was found that the blood flow approximately followed the vessel wall and that maximum velocity was approximately 1 m/s, which is a normal value for a healthy person.

Using the National Science Foundation (NSF)--NCAR Gulfstream V and the NSF--Wyoming King Air research aircraft during the Terrain-Induced Rotor Experiment (T-REX) in March-April 2006, six cases of Sierra Nevada mountain waves were surveyed with 126 cross-mountain legs. The goal was to identify the influence of the tropopause on waves entering the stratosphere. During each flight leg, part of the variation in observed parameters was due to parameter layering, heaving up and down in the waves. Diagnosis of the combined wave-layering signal was aided with innovative use of new GPS altitude measurements. The ozone and water vapor layering correlated with layered Bernoulli function and cross-flow speed. GPS-corrected static pressure was used to compute the vertical energy flux, confirming, for the first time, the Eliassen--Palm relation between momentum and energy flux (EF = -U * MF). Kinetic (KE) and potential (PE) wave energy densities were also computed. The equipartition ratio (EQR = PE/KE) changed abruptly across the tropopause, indicating partial wave reflection. In one case (16 April 2006) systematically reversed momentum and energy fluxes were found in the stratosphere above 12 km. On a 'wave property diagram,' three families of waves were identified: up-and downgoing long waves (30 km) and shorter (14 km) trapped waves. For the latter two types, an explanation is proposed related to secondary generation near the tropopause and reflection or secondary generation in the lower stratosphere.

Different frequency bands were used for the simultaneous sampling of multiple lines. Findings reveal that the proposed method significantly reduces the time spent on data collection for color flow map (CFM).

Insulin promotes dephosphorylation and activation of glycogen synthase (GS) by inactivating glycogen synthase kinase (GSK) 3 through phosphorylation. Insulin also promotes glucose uptake and glucose 6-phosphate (G-6-P) production, which allosterically activates GS. The relative importance of these two regulatory mechanisms in the activation of GS in vivo is unknown. The aim of this study was to investigate if dephosphorylation of GS mediated via GSK3 is required for normal glycogen synthesis in skeletal muscle with insulin. We employed GSK3 knockin mice in which wild-type GSK3[alpha] and -[beta] genes are replaced with mutant forms ([GSK3[alpha]/[beta].sup.S21A/S21A/S9A/S9A]), which are nonresponsive to insulin. Although insulin failed to promote dephosphorylation and activation of GS in [GSK3[alpha]/[beta].sup.S21A/S21A/S9A/S9A] mice, glycogen content in different muscles from these mice was similar compared with wild-type mice. Basal and epinephrine-stimulated activity of muscle glycogen phosphorylase was comparable between wild-type and GSK3 knockin mice. Incubation of isolated soleus muscle in Krebs buffer containing 5.5 mM glucose in the presence or absence of insulin revealed that the levels of G-6-P, the rate of [[sup.14]C]glucose incorporation into glycogen, and an increase in total glycogen content were similar between wild-type and GSK3 knockin mice. Injection of glucose containing 2-deoxy-[[sup.3]H]glucose and [[sup.14]C]glucose also resulted in similar rates of muscle glucose uptake and glycogen synthesis in vivo between wild-type and GSK3 knockin mice. These results suggest that insulin-mediated inhibition of GSK3 is not a rate-limiting step in muscle glycogen synthesis in mice. This suggests that allosteric regulation of GS by G-6-P may play a key role in insulin-stimulated muscle glycogen synthesis in vivo. glycogen synthase kinase 3; phosphorylase; muscle metabolism; insulin signaling; type 2 diabetes

The performance analysis of a method based on transmitting pseudo-random sequences for spatial encoding in synthetic transmit aperture ultrasound imaging is presented.