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Glycogen content and contraction strongly regulate glycogen synthase (GS) activity, and the aim of the present study was to explore their effects and interaction on GS phosphorylation and kinetic properties. Glycogen content in rat epitrochlearis muscles was manipulated in vivo. After manipulation, incubated muscles with normal glycogen [NG, 210.9 [+ or -] 7.1 mmol/kg dry weight (dw)], low glycogen (LG; 108.1 [+ or -] 4.5 mmol/kg dw), and high glycogen (HG; 482.7 [+ or -] 42.1 mmol/kg dw) were contracted or rested before the studies of GS kinetic properties and GS phosphorylation (using phospho-specific antibodies). LG decreased and HG increased GS [K.sub.m] for UDP-glucose (LG: 0.27 [+ or -] 0.02 < NG: 0.71 [+ or -] 0.06 < HG: 1.11 [+ or -] 0.12 mM; P < 0.001). In addition, GS fractional activity inversely correlated with glycogen content (R = -0.70; P < 0.001; n = 44). Contraction decreased [K.sub.m] for UDP-glucose (LG: 0.14 [+ or -] 0.01 = NG: 0.16 [+ or -] 0.01 < HG: 0.33 [+ or -] 0.03 mM; P < 0.001) and increased GS fractional activity, and these effects were observed independently of glycogen content. In rested muscles, GS [Ser.sup.641] and [Ser.sup.7] phosphorylation was decreased in LG and increased in HG compared with NG. GSK-3[beta] [Ser.sup.9] and AMPK[alpha] [Thr.sup.172] phosphorylation was not modulated by glycogen content in rested muscles. Contraction decreased phosphorylation of GS [Ser.sup.641] at all glycogen contents. However, contraction increased GS [Ser.sup.7] phosphorylation even though GS was strongly activated. In conclusion, glycogen content regulates GS affinity for UDP-glucose and low affinity for UDP-glucose in muscles with high glycogen content may reduce glycogen accumulation. Contraction increases GS affinity for UDP-glucose independently of glycogen content and creates a unique phosphorylation pattern uridine diphosphate; adenosine monophosphate kinase; glycogen synthase kinase-3; acetyl-coenzyme A carboxylase; enzyme kinetic

A method for designing waveforms for temporal encoding in medical ultrasound imaging is described. The proposed waveform is designed to excite only frequencies where the transducer has a large amplification. dsi

Various effects, including the effect of phase errors and motion effects that influence the focusing in the synthetic aperture vector flow imaging technique are analyzed. The results prove that the motion effects highly affect the signal-to-noise ratio of the axial and lateral motion.

A method to improve the precision of the estimation of the lateral component of the displacement using the phase of the complex correlation function is described. The lateral profile of the PSF shows oscillations present in the axial direction of a PSF that is conventional.

A method for determining both velocity magnitude and angle in a synthetic aperture ultrasound system is described. The approach uses directional beamforming along the flow direction and cross correlation to determine velocity magnitude. The angle of the flow is determined from the maximum normalized correlation calculated as a function of angle. This assumes the flow direction is within the imaging plane. Simulations of the angle estimation method show both biases and standard deviations of the flow angle estimates below 3[degrees] for flow angles from 20[degrees] to 90[degrees] (transverse flow). The method is also investigated using data measured by an experimental ultrasound scanner from a flow rig. A commercial 128 element 7-MHz linear array transducer is used, and data are measured for flow angles of 60[degrees] and 90[degrees]. Data are acquired using the RASMUS experimental ultrasound scanner, which samples 64 channels simultaneously. A 20-[micro]s chirp was used during emission and eight virtual transmit sources were created behind the transducer using 11 transmitting elements. Data from the eight transmissions are beamformed and coherently summed to create high-resolution lines at different angles for a set of points within the region of flow. The velocity magnitude is determined with a precision of 0.36% (60 [degrees]) and 1.2% (90[degrees]), respectively. The 60[degrees] angle is estimated with a bias of 0.54[degrees] and a standard deviation of 2.1[degrees]. For 90[degrees] the bias is 0.0003[degrees] and standard deviation 1.32[degrees]. A parameter study with regard to correlation length and number of emissions is performed to reveal the accuracy of the method. Real time data covering 2.2 s of the carotid artery of a healthy 30-year-old male volunteer is acquired and then processed offline using a computer cluster. The direction of flow is estimated using the above mentioned method. It is compared to the flow angle of 106[degrees] with respect to the axial direction, determined visually from the B-mode image. For a point in the center of the common carotid artery, 76% of the flow angle estimates over the 2.2 s were within 10[degrees] of the visually determined flow angle. The standard deviation of these estimates was below 2.7[degrees]. Full color flow maps from different parts of the cardiac cycle are presented, including vector arrows indicating both estimated flow direction and velocity magnitude. Index Terms--Angle determination, medical ultrasound, synthetic aperture, vector velocity estimation.

We report significant failure rates (28%, 95% confidence interval 15%-45%) after administering 1 g azithromycin to men with Mycoplasma genitalium-positive nongonococcal urethritis. In vitro evidence supported reduced susceptibility of M. [...]

A systematic parameter analysis is performed to evaluate the transverse oscillation (TO) method using the ultrasound simulation program and the experimental scanner RASMUS. At angles more than 45 degrees, the TO method can produce relatively good estimates of the transverse velocity, and thus, it is possible to estimate blood velocities at angles in which a conventional scanner fails to detect any velocity at all.

A method for exciting all transmitters in every transmission and separating them at the receiver is proposed, by designing a filterbank consisting of the matched filters corresponding to the excitation waveforms to decode the different transmitters at the receiver. The major advantage of the approach is that the acquired information from the multiple transmitters can be separated from each other instantaneously, and it is not necessary to use multiple transmissions.

Insulin-stimulated glucose uptake and incorporation of glucose into skeletal muscle glycogen contribute to physiological regulation of blood glucose concentration. In the present study, glucose handling and insulin signaling in isolated rat muscles with low glycogen (LG, 24-h fasting) and high glycogen (HG, refed for 24 h) content were compared with muscles with normal glycogen (NG, rats kept on their normal diet). In LG, basal and insulin-stimulated glycogen synthesis and glycogen synthase activation were higher and glycogen synthase phosphorylation ([Ser.sup.645], [Ser.sup.649], [Ser.sup.653], [Ser.sup.657]) lower than in NG. GLUT4 expression, insulin-stimulated glucose uptake, and PKB phosphorylation were higher in LG than in NG, whereas insulin receptor tyrosyl phosphorylation, insulin receptor substrate-l-associated phosphatidylinositol 3-kinase activity, and GSK-3 phosphorylation were unchanged. Muscles with HG showed lower insulin-stimulated glycogen synthesis and glycogen synthase activation than NG despite similar dephosphorylation. Insulin signaling, glucose uptake, and GLUT4 expression were similar in HG and NG. This discordant regulation of glucose uptake and glycogen synthesis in HG resulted in higher insulin-stimulated glucose 6-phosphate concentration, higher glycolytic flux, and intracellular accumulation of nonphosphorylated 2-deoxyglucose. In conclusion, elevated glycogen synthase activation, glucose uptake, and GLUT4 expression enhance glycogen resynthesis in muscles with low glycogen. High glycogen concentration per se does not impair proximal insulin signaling or glucose uptake. 'Insulin resistance' is observed at the level of glycogen synthase, and the reduced glycogen synthesis leads to increased levels of glucose 6-phosphate, glycolytic flux, and accumulation of nonphosphorylated 2-deoxyglucose. glucose transporter 4; protein kinase B; glycogen synthase kinase-3; phosphorylation; glucose metabolism; glycolytic flux; rat

Glucocorticoids cause insulin resistance in skeletal muscle. The aims of the present study were to investigate the effects of contraction on glucose uptake, insulin signaling, and regulation of glycogen synthesis in skeletal muscles from rats treated with the glucocorticoid analog dexamethasone (1 mg*[kg.sup.-1]*[day.sup.-1] ip for 12 days). Insulin resistance in dexamethasone-treated rats was confirmed by reduced insulin-stimulated glucose uptake (~35%), glycogen synthesis (~70%), glycogen synthase activation (~80%), and PKB [Ser.sup.473] phosphorylation (~40%). Chronic dexamethasone treatment did not impair glucose uptake during contraction in soleus or epitrochlearis muscles. In epitrochlearis (but not in soleus), the presence of insulin during contraction enhanced glucose uptake to similar levels in control and dexamethasone-treated rats. Contraction also increased glycogen synthase fractional activity and dephosphorylated glycogen synthase at [Ser.sup.645], [Ser.sup.649], [Ser.sup.653], and [Ser.sup.657] normally in muscles from dexamethasone-treated rats. After contraction, insulin-stimulated glycogen synthesis was completely restored in epitrochlearis and improved in soleus from dexamethasone-treated rats. Contraction did not increase insulin-stimulated PKB [Ser.sup.473] or glycogen synthase kinase-3 (GSK-3) phosphorylation. Instead, contraction increased GSK-3[beta] [Ser.sup.9] phosphorylation in epitrochlearis (but not in soleus) in muscles from control and dexamethasone-treated rats. In conclusion, contraction stimulates glucose uptake normally in dexamethasone-induced insulin resistant muscles. After contraction, insulin's ability to stimulate glycogen synthesis was completely restored in epitrochlearis and improved in soleus from dexamethasone-treated rats. insulin signaling; glycogen synthase kinase-3; protein kinase B; glucocorticoids; AMP-activated protein kinase

During the Southern Ocean Waves Experiment (SOWEX) an aircraft carried a down-looking video camera to help document the sea surface. Reflected images of the aircraft were intermittently observed in the video recorded at 15-30-m height under light and variable wind conditions. A numerical simulation was developed to relate image contrast to the gravity-capillary wave contribution to sea-surface mean square slope (mss). 'Carnival fun-house' mirror-type distortions of the image in the absence of the gravity-capillary waves relate to intermediate-scale wave persistence when wind forcing stops. Video image estimates of mss correlated better with 36-GHz scanning radar altimeter estimates than with the wind speed measured at 30-m height. When the gravity-capillary waves disappeared in the absence of wind forcing, about one-third of the 0.0015 residual mss was contributed by the dominant waves, and about two-thirds was contributed by the 1-10-m wavelength region. Near the shores of a lake in Alaska, reflected aircraft images were also observed, indicating that the gravity-capillary wave contribution to mss was only about 0.000 001, even though the wind speed at the 160-m aircraft height was 10 m/s. Index Terms--Light wind, mean square slope (MSS), microwave, optical, sea surface.

A system is designed for imaging research flexibility. The system can acquire multichannel data in real-time from multi-element ultrasound transducers, and can perform some real-time processing on the acquired data.

A compact medical ultrasound beamformer architecture that uses oversampled 1-bit analog-to-digital (A/D) converters is presented. A 32-channel beamformer can be implemented in one standard field programmable gate array (FPGA), which can be programmed easily and upgraded.

The possibility of increasing the frame rate in ultrasound imaging by using modulated excitation signals is investigated. Linear array-coded imaging and sparse synthetic transmit aperture imaging are considered, and the trade-offs between frame rate, imaging quality, and signal-to-noise ratio (SNR) are discussed.

The superiority of linear FM signals was shown in terms of signal-to-noise ratio and robustness to tissue attenuation. It is shown that for the small time-bandwidth (TB) products available in ultrasound, the rectangular spectrum approximation is not valid, which reduces the effectiveness of weighting.

The concepts of signal modulation and matched filtering are given, and a simple model of attenuation relates the matched filter response with the ambiguity function, known from radar. Based on this analysis and the properties of the ambiguity function, the selection of coded waveforms suitable for ultrasound imaging is discussed.

A method for flow estimation using synthetic aperture imaging and focusing along the flow direction is presented. The method can find correct velocity magnitude for any flow angle, and full color flow images can be measured using 32 to 128 pulse emissions. The approach can be used for both tissue and blood velocity determination.

BACKGROUND: Air pollution exposure has been linked to coronary heart disease, although evidence on [PM.sub.2.5] and myocardial infarction (MI) incidence is mixed. OBJECTIVES: This prospective cohort study aimed to investigate associations between long-term exposure to air pollution and MI incidence, adjusting for road traffic noise. METHODS: We used data from the nationwide Danish Nurse Cohort on 22,882 female nurses (>44 years of age) who, at recruitment in 1993 or 1999, reported information on cardiovascular disease risk factors. Data on MI incidence was collected from the Danish National Patient Register until the end of 2014. Annual mean concentrations of particulate matter (PM) with a diameter RESULTS: Of the 22,882 women, 641 developed MI during a mean follow-up of 18.6 y, 121 (18.9%) of which were fatal. Reported hazard ratios (HRs) were based on interquartile range increases of 5.3, 5.5, 8.1, and 11.5 [micro]g/[m.sup.3] for [PM.sub.2.5], [PM.sub.10], N[O.sub.2], and [NO.sub.X], respectively. In Model 1, we observed a positive association between a 3-y running mean of [PM.sub.2.5] and an overall incident MI with an HR = 1.20 (95% CI: 1.07, 1.35), which attenuated to HR = 1.06 (95% CI: 0.92, 1.23) in Model 2. In Model 1 for incident fatal MI, we observed a strong association with a 3-y running mean of [PM.sub.2.5], with an HR= 1.69 (95% CI: 1.33, 2.13), which attenuated to HR= 1.35 (95% CI: 1.01, 1.81) in Model 2. Similar associations were seen for [PM.sub.10], with 3-y, Model 2 estimates for overall and fatal incident MI of HR = 1.06 (95% CI: 0.91, 1.23) and HR = 1.35 (95% CI: 1.01, 1.81), respectively. No evidence of an association was observed for N[O.sub.2] or [NO.sub.x]. For all pollutants, associations in Model 2 were robust to further adjustment for road traffic noise in Model 3 and were similar for a 1-y running mean exposure. CONCLUSIONS: We found no association between long-term exposure to [PM.sub.2.5], [PM.sub.10], N[O.sub.2], or [NO.sub.x] and overall MI incidence, but we observed positive associations for [PM.sub.2.5] and [PM.sub.10] with fatal MI. We present novel findings that the association between PM and MI incidence is robust to adjustment for road traffic noise. https://doi.org/10.1289/EHP5818, Introduction There is growing evidence on the association between long-term exposure to air pollution and cardiovascular disease (CVD) mortality (Faustini et al. 2014; Lelieveld et al. 2019; Pope et al. [...]

Diseases in the cardiovascular system can be diagnosed using medical ultrasound imaging as the distribution and magnitude of blood velocities contain valuable information for diagnosis. An estimator (CMLE) based on the correlation (C) properties inherited from fluid flow and maximum likelihood estimation is derived and evaluated.

An innovative procedure for directional velocity estimation is described and discussed.

An innovative procedure for directional velocity is described and discussed.

An innovative approach for acquiring flow images using synthetic aperture techniques in medical ultrasound is described and discussed.

A new method to increase the signal-to-noise ratio (SNR) of synthetic transmit aperture imaging is investigated. The approach utilizes multiple elements to emulate a spherical wave, and the conventional short excitation pulse is replaced by a linear frequency-modulated (FM) signal. The approach is evaluated in terms of image quality parameters in comparison to linear array imaging. Field II simulations using an 8.5-MHz linear array transducer with 128 elements show an improvement in lateral resolution of up to 30% and up to 10.75 % improvement in contrast resolution for the new approach. Measurements are performed using our experimental multichannel ultrasound scanning system, RASMUS. The designed linear FM signal obtains temporal sidelobes below -55 dB, and SNR investigations show improvements of 4-12 dB. A 30 mm ([approximately equal to] 45%) increase in penetration depth is obtained on a multitarget phantom with 0.5 dB/[cm MHz] attenuation. Furthermore, in vivo images of the abdomen are presented, which demonstrate the clinical application of the new approach. Index Terms--Experimental ultrasound scanning system, Field II, linear FM signals, multielement defocusing, synthetic transmit aperture ultrasound imaging.

Neuropeptide Y (NPY) has prominent cardiovascular effects in mammals and sharks, but no such effect has previously been demonstrated in any teleost fish. In the Atlantic cod, we found that cod NPY ([10.sup.-10]-[10.sup.-6] M) relaxed celiac arteries precontracted with epinephrine, and weak contractions were elicited in intestinal ring preparations. A few NPY-immuno-reactive nerve fibers were present along small gut arteries. The results suggest that cod NPY produces vasorelaxation both by a direct action on smooth muscle and by release of prostaglandins, but with no involvement of nitric oxide, leukotrienes, or endothelium-derived relaxing factors. An additional indirect effect involving another neurotransmitter may occur. Cod NPY ([10.sup.-7] M) and human NPY ([10.sup.-7] M) had identical effects on the vessels. Small differences only in the effects of porcine [[Leu.sup.31],[Pro.sup.34]]NPY, NPY-(13-36), and cod NPY suggest the presence of a [Y.sub.1] subfamily receptor, similar to the zebrafish Ya receptor. A physiological role for NPY in teleost vasculature is concluded, but surprisingly the effect, a vasodilation, is opposite to that in mammals and is mediated by prostaglandins. cod neuropeptide Y; celiac artery; cod intestine; receptor

Cross-achievements, or combined effects, are examined for drinking water protection and reductions in nitrogen fertilizer use. The impact of cross-achievements on policy evaluations, particularly for cost-benefit analyses, is also discussed.

Pulsed ultrasound field was used to derive a new estimator to determine two dimensional velocity vectors.