Doppler Analysis Research Articles

Color Doppler Evaluation of Arterial Resistive Index in Infantile Hemangioma: A Useful Parameter to Monitor the Response to Oral Propranolol?

Infantile hemangioma (IH) is the most common benign vascular tumor in childhood. In more than 85% of all cases, IHs undergo spontaneous involution, but nearly 10–12% of IHs develop complications and require immediate therapy. Oral propranolol is currently the first-line treatment for IHs. Color Doppler ultrasound is the gold standard in the diagnosis of deep IH, and it is used to evaluate the morphological change and the modification of vascularization that occur during its evolution and treatment. To date, only few data in the literature described the changes of intralesional arterial resistive index (RI) during treatment with propranolol; particularly, some authors have shown an increase of intralesional arterial RI in IHs with clinical regression during treatment with propranolol. The objective of this paper is to evaluate the changes of RI of the intralesional arteries of the IHs during the treatment with oral propranolol. We retrospectively analyzed a total of 64 IHs in 60 patients treated with oral propranolol with a good clinical response. Gray-scale ultrasonography and color Doppler imaging were performed before and during the therapy. The intralesional RIs were measured before and during the treatment. For each lesion, we recorded the RI values, and then we calculated the mean RI value for any single lesion. We compared the mean RI value observed at the baseline with the mean RI value of the last detectable sampling at color Doppler. We also compared between them the mean RI values observed during intermediate ultrasound. The RI values were compared in 44 lesions, with at least two significant samplings of RI. In the 44 lesions compared, we did not find statistically significant variations in the mean RI values between the baseline control and the values recorded at the last post-treatment control. The time trend of mean RI values of the intermediate color Doppler analysis performed between the first pre-treatment control and the last measurable control did not show any statistically significant variation in the trend of mean RI values. Contrarily to what has been described by some authors, in our experience, we have not observed an increase of RI in IHs treated with oral propranolol.

Normal ranges of fetal heart rate values for healthy fetuses in Poland, as determined by ultrasound between weeks 18and 29 of gestation.

Fetal heart rate (FHR) is commonly used to assess fetal well-being. The aim was to establish normal ranges of FHR during pregnancy by umbilical artery (UMB-A) Doppler analysis in a healthy Polish population. The study was conducted in a tertiary center for fetal cardiology. Data on gestational age (GA), FHR measured on UMB-A, cardiac problems, and extracardiac problems were collected. All fetuses underwent echocardiographic examination. The inclusion criteria comprised normal fetal biometry and biophysical profile, labels of "normal heart anatomy and normal heart function", "no extracardiac malformations", and no "extracardiac anomalies". Based on the data from 258 healthy fetuses, a scatter graph with regression line giving a prognosis of normal values for FHR during pregnancy was prepared (95% confidence interval). The regression equation for FHR, as function of GA in weeks, was found to be: FHR (beats/minute) = 149 - GA according to biometry (weeks) × 0.22; (r = -0.1032; P = 0.098); FHR (beats/minute) = 148 - GA according to the last menstrual period (weeks) × 0.16; (r = -0.0722; P = 0.253). The 5th, 50th, 95th percentiles, mean and standard deviation of FHR between weeks 18 and 29 of gestation were calculated. We present the normal ranges for FHR measured on UMB-A for weeks 18 to 29 of gestation in healthy fetuses with normal heart function and anatomy. The obtained values may be of value to departments of obstetrics and should be considered important elements of the basic fetal ultrasound report.

Особливості ренального кровотоку при гострому пошкодженні нирок у недоношених новонароджених дітей з гемодинамічно значущою відкритою артеріальною протокою

Hemodynamically significant patent ductus arteriosus (HSPDA) in premature infants leads to renal hypoperfusion due to the phenomenon of «stealing» of the systemic circulation, which can contribute to the development of acute kidney injury (AKI). The use of ultrasound Doppler sonography of the renal vessels can be effective in assessing renal blood flow and in the early diagnosis of acute renal failure. Purpose — to assess the prognostic significance of the state of renal blood flow in the first day of life in premature infants with HSPDA in the early diagnosis of AKI. Materials and methods. We examined 40 preterm infants (gestational age 29–36 weeks) with HSPDA. Distribution of the examined patients: the group with AKI — 23 children, the group without AKI — 17 children. The observation period was 10 days. The patients underwent echocardiography with Doppler analysis using a broadband microconvex probe with a frequency of 5–8 MHz (TOSHIBA Nemso XG) at 5–11 hours of life. Color Doppler ultrasound scanning of renal vessels was performed on the first, third and tenth days of life. The parameters of blood flow in the main renal and interlobar renal arteries were studied: peak systolic velocity (PSV) and end diastolic velocity (EDV) of blood flow, resistance index (RI). Diagnosis and stratification of AKI severity met the KDIGO neonatal modification criteria. Results. On the third to fifth day of life, AKI was diagnosed in 23 (57.5%) children, but already in the first day of life, compared with patients without AKI, a significant decrease in PSV parameters of blood flow in the main renal artery was noted (20.6±5.87 cm/sec versus 25.4±6.17 cm/sec in children without AKI, p<0.02). In addition, the main changes in the first day of life in patients with AKI were revealed at the level of the interlobar renal artery, namely: a decrease in PSV blood flow (11.10±3.329 cm/sec versus 18.48±3.014 cm/sec in children without AKI, p<0.001) and EDV of blood flow (2.83±2.063 cm/sec versus 6.16±2.447 cm/sec in children without AKI, p<0.001), increased RI (0.758±0.137 versus 0.666±0.1216 in children without AKI, p<0.02). On the third day of life at AKI, there was a disorder in the parameters of blood flow in the interlobaric renal artery, the value of which on the tenth day of life did not differ from the parameters of children without AKI. Conclusions. In premature infants with HSPDA, who were diagnosed with AKI on the third to fifth day of life, in the first day of life, there is a decrease in PSV blood flow parameters in the main renal artery, changes in blood flow in the interlobar renal artery, namely: a decrease in PSV and EDV blood flow, an increase in RI. Thus, the assessment of the state of blood flow in the interlobar renal artery on the first day of life in premature infants with HSPDA is of diagnostic value for the timely determination of the risk group for AKI. The research was carried out in accordance with the principles of the Helsinki declaration. The study protocol was approved by the Local ethics committee of all participating institution. The informed consent of the patient was obtained for conducting the studies. No conflict of interest was declared by the authors. Key words: premature infants, patent ductus arteriosus, renal blood flow, acute kidney injury.

Evaluation of effectiveness of complex treatment of chronic generalized periodontitis using original splinting design

Relevance. The relevance of the study is dictated by the high prevalence of periodontal disease among young people and by the need to search for new approaches to periodontitis treatment in order to increase the effectiveness of treatment at early stages of pathological process.
 Objective. To evaluate the effectiveness of complex treatment of chronic generalized periodontitis (CGP) of mild severity using a removable splinting construction made according to the author's technique.
 Materials and methods. At the orthopedic stage of the complex treatment of mild CGP, splinting constructions were used for 47 young patients: in the main group (n = 16) the authors treatment and preventive splint, in the first comparison group (n = 15) a removable metal splint, in the second comparison group (n = 16) a fixed adhesive fiber splint. Periodontal hemodynamics was assessed using ultrasound Doppler analysis 1, 6 and 12 months after the therapeutic measures and tooth immobilization. To identify the possible negative impact of the treatment on the quality of life (QOL) in patients with splint constructions, we used the OHIP-14-Ru questionnaire; the follow-up period was 1.3, 6, and 12 months.
 Results. Dental immobilization contributed to the improvement of blood flow in the periodontal tissues in the short and long term follow-up, so after 12 months: Vam in the main group increased by 39,8 % and amounted to 0,397 0,004 cm / s, in patients of the comparison groups Vam was 0,329 0,006 cm / s and 0,335 0,003 cm / s, respectively, that is 15,4 % and 18,4 % higher compared with the figures before treatment. The quality of life index for patients using splinting constructions made according to the author's technique, by the OHIP-14-Ru questionnaire was assessed as good 1 year after (3.46 0.59).
 Conclusions. The use of the proposed original orthopedic design in a complex plan for mild periodontitis treatment helps to improve regional blood circulation and stabilize the pathological process.

Volumetric Flow Estimation in a Coronary Artery Phantom Using High-Frame-Rate Contrast-Enhanced Ultrasound, Speckle Decorrelation, and Doppler Flow Direction Detection.

The coronary flow reserve (CFR), relating to the volumetric flow rate, is an effective functional parameter to assess the stenosis in the left anterior descending (LAD) coronary artery. We have recently proposed to use high-frame-rate (HFR) contrast-enhanced ultrasound (CEUS) to estimate the volumetric flow rate using ultrasound (US) speckle decorrelation (SDC) without any assumptions about the velocity profile. However, this method still has challenges in imaging deep and small vessels, such as LAD. In this study, we proposed to address the challenges and demonstrate the feasibility of volumetric flow rate measurement in a coronary mimicking phantom with pulsatile flow using a 1-D array cardiac probe, vector Doppler, and an optimal probe rotation/tilting for flow direction detection. Both simulations and in vitro experiments were conducted to validate the proposed method. It is shown that in-plane velocities estimated by vector Doppler under a 10° probe tilting resulted in smaller percentage error (+5.2%) in flow rate estimates than that in US imaging velocimetry (-20.2%) although their relative standard deviations were very close, being 2.6 and 2.8 ml/min, respectively. The flow rate estimated by SDC without direction detection had an error higher than 70%. A 10° tilting of the probe had the best results in flow rate estimation compared to the 5° or 15° tilting. Realistic global motions in the LAD increased the flow rate estimation error from 5.2% to 14.2%. It is concluded that it is feasible to measure the volumetric flow rate in a coronary artery flow phantom with a conventional cardiac probe, using HFR acquisition, Doppler, and SDC analysis. Potentially, this technique could also be applied to investigate the volumetric flow rate in other small vessels similar to the LAD.

Adaptation of lenvatinib treatment in patients with hepatocellular carcinoma and portal vein tumor thrombosis.

The aim of this study was to clarify the adaptation of lenvatinib treatment in patients with hepatocellular carcinoma (HCC) and portal vein tumor thrombosis (PVTT). Fifty-three patients with HCC were treated with lenvatinib. Before and after treatment blood sampling, patients were examined by computed tomography and ultrasonography. In patients with portal trunk invasion (Vp4), the analysis focused on the degree of occlusion due to the tumor in the portal trunk. In patients without major PVTT {ie, invasion of the primary branch of the portal vein [Vp3] or Vp4}, portal blood flow volume was measured by Doppler analysis; however, Doppler analysis is difficult to perform in patients with major PVTT, so the time from administration of the contrast agent to when it reached the primary branch of the portal vein (portal vein arrival time) was evaluated with the contrast agent Sonazoid. Patients with Vp4 had a significantly worse prognosis than patients with Vp3 and a significant increase in Child-Pugh score at 2months. Patients with major PVTT had a poor prognosis if the degree of occlusion of the portal trunk was 70% or more. In patients without major PVTT, portal blood flow was significantly decreased after administration of lenvatinib; and in patients with major PVTT, the hepatic artery and portal vein arrival times were significantly increased. Lenvatinib treatment should be avoided in patients with Vp4 with a high degree of portal trunk occlusion because of concerns about decreased portal blood flow.

Simultaneous velocity and concentration profiling of nuclear waste suspensions in pipe flow, using ultrasonic Doppler and backscatter analysis

Complex magnox ponds at Sellafield retain hydroxide-based sludge with unknown physicochemical properties. The sludge is a corroded form of magnesium-based fuel cladding used in first generation magnox reactors. Long term storage and open-air aqueous conditions are major contributors to corrosion. Waste needs to be transported to interim storage using engineered pipelines. Remote in situ characterisation of sludge was achieved using a non-invasive ultrasonic velocity profiler (UVP). The UVP uses raw velocity and echo amplitude to extract velocity and acoustic profiles. Profiles are used to understand effect of particle size and concentration on attenuation. Spherical glass particles with two size distributions of known acoustic behaviour were analysed to establish acoustic profiles. 4MHz frequency transducers were mounted in-line on engineered pipelines, 90 deg and 135 deg to flow. Data were extracted from in situ transducers for validation and non-contact probes were utilised to prove data could be collected safely without exposure. Flow rate was varied to ensure full developed flow before analysis. Profiles extracted from concentration arrays were analysed to understand particle segregation in horizontal pipe arrangements and attenuation. Remote in-line characterisation allows safe analysis, whilst in-line characterisation saves time and money. Moving forward, complex non-defined nuclear simulants will be analysed to investigate the UVP's limitations.

OC11.04: Effect of maternal hyperoxygenation on pulmonary circulation in growth‐restricted fetuses: a machine learning analysis of Doppler

OC11.04: Effect of maternal hyperoxygenation on pulmonary circulation in growth‐restricted fetuses: a machine learning analysis of Doppler

POSSIBILITIES OF ARGININE-CONTAINING THERAPY IN THE TREATMENT OF NEUROLOGICAL MANIFESTATIONS OF OSTEOCHONDROSIS OF THE LUMBAR PART OF THE SPINE

Purpose of the study – to estimate the pathogenetic expediency of L-arginine use inpatients with neurological manifestations of osteochondrosis of the spine lumbar parton the basis of estimation of the clinical picture, cerebral Doppler data and analysis ofthe blood plasma levels of some indices of endothelial dysfunction, such as fibronectin,soluble fms-similar tyrosine kinase 1 (sFlt - 1) and tumor necrotic factor (TNF-α),using Glutargine as an example. Material and methods. 104 male patients with neurological manifestations ofosteochondrosis of the lumbar spine at the age of 25-45 years (mean age 34.05 ± 5.7)without obesity, somatic and vascular pathology and 25 practically healthy persons,who did not differ in age from groups of the patients under study, have been examined.Among the examined patients, there were 50 patients with radiculopathies against abackground of herniated intervertebral discs, verified by means of neuroimaging, and54 patients with reflex manifestations of osteochondrosis of the lumbar part of the spine.The study of the clinical picture of osteochondrosis neurological manifestations of thelumbar spine was carried out by the method of standard neurological examinationusing a visual- analogue pain scale.The state of the autonomic nervous system was assessed using standard tests forautonomic reactivity and autonomic provision of activity, as well as using theQuestionnaire to identify signs of vegetative changes and the Study Scheme to identifysigns of autonomic disorders (O.M. Wein, 1993).The study of cerebral circulation was carried out by the method of extra-intracranialDoppler ultrasonography according to the standard techniques on the Sonomed-350apparatus using the Overshut test for cerebrovascular reactivity.Concentration of fibronectin in the blood plasma, tumor necrosis factor alpha andsoluble fms- similar tyrosine kinase was investigated by enzyme immunoassay accordingto the manufacturer's procedure under laboratory conditions.The paired Student's test and Fisher's angular Phi-transformation are used.Results. Statistically significant decrease of the pain syndrome has been revealedaccording to the VAS scale in the group of patients, who took Glutargin in the complextreatment. Significant changes in autonomic homeostasis have not been revealed whenusing Glutargin. The index of endothelium-dependent vasodilation in the group ofpatients, who took glutargin after treatment, approached the values of the control group(0.3 ± 0.06 at the values in the control group - 0.3 ± 0.096).Analysis of the data of fibronectin investigation, soluble fms-similar tyrosine kinase-1(sFlt - 1) and tumor necrotic factor (TNF-α) in the groups of patients with radicularmanifestations of osteochondrosis of the spine lumbar part before and after treatmenttestifies to that there were positive changes in the studied parameters in both groupsof patients, both with the use of standard treatment, and with the use of Glutargin,however, only in the group of patients, who took Glutargin in addition to the standardtreatment, a decrease in the content of fibronectin and tumor necrotic factor in bloodplasma acquired statistical significance. The increase in the indices of soluble fmslike tyrosine kinase-1 (sFlt - 1) in both groups of patients was insignificant and notstatistically veritable.Conclusions. Glutargin use in the complex treatment of patients with radicularneurological manifestations of lumbar osteochondrosis has a positive effect on theclinical course, reliably reducing the intensity of the pain syndrome and leads to animprovement in the endothelial functional state.

​Color Doppler Ultrasonographic Characteristics of Embryonic Development and Mortality in Dairy Cows

Background: Embryonic mortality is one of the major factors leading to reproductive failure, decreased fertility and delayed pregnancy in cattle. Method: The study was aimed for investigating the incidence of embryonic mortality(EM), differentiate embryonic development and mortality based on color Doppler ultrasonographic characteristics. Different characteristics correlated were corpus luteum(CL) vascularity, embryonic development and EM features, monitored on day 21 post-insemination. Result: The overall incidence of EM was recorded to be 25%, with 15% and 10% mortality occurred between days 21-28 and 28-35 of gestation. Color Doppler analysis stated that, the CL in pregnant cows had a higher percentage of luteal tissue with positive Doppler signals on initial examination (day 21) differing significantly (P less than 0.01) from non-pregnant and consistently increased till the end of the examination. However, cows with EM had a significantly lower CL vascularity than pregnant (P less than 0.05) but significantly higher (P less than 0.05) than non-pregnant cows on day 21. Embryos from pregnant cows (detected by 28 days) increased in size along the days of examination. However, cows diagnosed with EM showed signs (day 28), which included reduced intra-uterine allantoic fluid, absence of embryo proper with an embryonic heartbeat, hyperechoic free-floating embryonic debris in the uterus and distorted allanto-chorionic membrane. In conclusion, the present study firmly supports color Doppler ultrasonography in diagnosis of pregnant cows based on CL vascularity, visualizing the different characteristics signs of EM, and detecting non-pregnant animals undergoing EM as early as day 21.

Staging liver fibrosis after severe yellow fever with ultrasound elastography in Brazil: A six-month follow-up study.

Yellow fever (YF) is a hemorrhagic disease caused by an arbovirus endemic in South America, with recent outbreaks in the last years. Severe cases exhibit fulminant hepatitis, but there are no studies regarding its late-term effects on liver parenchyma. Thus, the aim of this study was to determine the frequency and grade of liver fibrosis in patients who recovered from severe YF and to point out potential predictors of this outcome. We followed-up 18 patients who survived severe YF during a recent outbreak (January-April 2018) in Brazil using ultrasound (US) with shear-wave elastography (SWE) at 6 months after symptoms onset. No patient had previous history of liver disease. Median liver stiffness (LS) was 5.3 (4.6-6.4) kPa. 2 (11.1%) patients were classified as Metavir F2, 1 (8.3%) as F3 and 1 (8.3%) as F4; these two last patients had features of cardiogenic liver congestion on Doppler analysis. Age and cardiac failure were associated with increased LS (p = 0.036 and p = 0.024, respectively). SAPS-3 at ICU admission showed a tendency of association with significant fibrosis (≥ F2; p = 0.053). 7 patients used sofosbuvir in a research protocol, of which none showed liver fibrosis (p = 0.119). We found a low frequency of liver fibrosis in severe YF survivors. US with SWE may have a role in the follow up of patients of age and / or with comorbidities after hospital discharge in severe YF, a rare but reemergent disease.

Screening of High-Risk Patient by Uterine Artery Doppler Analysis in The 1st Trimester to Predict Early Onset Pre-Eclampsia

Background: Preeclampsia (PE) is still a major obstetrical problem world-wide. First trimester prediction of PE is of great clinical importance, as it would allow clinicians to focus on high-risk groups and initiate prophylactic medical treatment. The first stage of pre-eclampsia begins in the first trimester by impaired placentation. High-resistant spiral arteries can be detected from the 11th week of gestation by uterine artery (UtA) Doppler examination. Objective: To assess the relationship between 1st trimester uterine artery pulsatility index (UtA PI) and the development of early onset PE.Patients and Methods: Prospective observational study was performed at Mansoura University Hospital. This study was conducted on 109 pregnant women who attended their routine antenatal care visits at the Outpatient Obstetrics and Gynecology Clinic of Mansoura University Hospital. Results: There were statistically high significant difference between both groups in the BMI (p = 0.003), and no statistically significant difference as regards the age, gravidity and gestational age (p > 0.05). Statistically significant difference was evident between two groups in the mean values of UtA PI (p = 0.028). The best cutoff value of UtA PI for the prediction of early onset preeclampsia was ≥ 2.03 with accuracy of 0.79, and that of BMI was ≥ 35 with accuracy of 0.93. Conclusion: This study revealed that first trimester uterine artery Doppler can be used as a reliable screening test for prediction of preeclampsia in high risk women. It is a reliable, noninvasive method of examining uteroplacental perfusion. Abnormal UA Doppler ultrasonography (elevated PI) in 11–14 weeks' gestation can predict pre-eclampsia.

Doppler Radar Analysis of the Eyewall Replacement Cycle of Hurricane Matthew (2016) in Vertical Wind Shear

AbstractHurricane Matthew (2016) was observed by ground-based polarimetric radars in Miami (KAMX), Melbourne (KMLB), and Jacksonville (KJAX) and a NOAA P3 airborne tail Doppler radar near the coast of the southeastern United States during an eyewall replacement cycle (ERC). The radar observations indicate that Matthew’s primary eyewall was replaced with a weaker outer eyewall, but unlike a classic ERC, Matthew did not reintensify after the inner eyewall disappeared. Triple Doppler analysis was calculated from the NOAA P3 airborne fore and aft radar scanning combined with the KAMX radar data during the period of secondary eyewall intensification and inner eyewall weakening from 19 UTC 6 October to 00 UTC 7 October. Four flight passes of the P3 aircraft show the evolution of the reflectivity, tangential winds, and secondary circulation as the outer eyewall became well-established. Further evolution of the ERC is analyzed from the ground-based single Doppler radar observations for 35 hours with high temporal resolution at a 5-minute interval from 19 UTC 6 October to 00 UTC 8 October using the Generalized Velocity Track Display (GVTD) technique. The single-Doppler analyses indicate that the inner eyewall decayed a few hours after the P3 flight, while the outer eyewall contracted but did not reintensify and the asymmetries increased episodically. The analysis suggests that the ERC process was influenced by a complex combination of environmental vertical wind shear, an evolving axisymmetric secondary circulation, and an asymmetric vortex Rossby wave damping mechanism that promoted vortex resiliency despite increasing shear.

Monitoring Lakes Surface Water Velocity with SAR: A Feasibility Study on Lake Garda, Italy

The SAR Doppler frequencies are directly related to the motion of the scatterers in the illuminated area and have already been used in marine applications to monitor moving water surfaces. Here we investigate the possibility of retrieving surface water velocity from SAR Doppler analysis in medium-size lakes. ENVISAT images of the test site (Lake Garda) are processed and the Doppler Centroid Anomaly technique is adopted. The resulting surface velocity maps are compared with the outputs of a hydrodynamic model specifically validated for the case study. Thermal images from MODIS Terra are used in support of the modeling results. The surface velocity retrieved from SAR is found to overestimate the numerical results and the existence of a bias is investigated. In marine applications, such bias is traditionally removed through Geophysical Model Functions (GMFs) by ascribing it to a fully developed wind waves spectrum. We found that such an assumption is not supported in our case study, due to the small-scale variations of topography and wind. The role of wind intensity and duration on the results from SAR is evaluated, and the inclusion of lake bathymetry and the SAR backscatter gradient is recommended for the future development of GMFs suitable for lake environments.

The Incidence of Peripheral Artery Disease in Patients with Rheumatoid Arthritis

Objectives: The basic aim of this study was to find the expression of PAD in a group of Rheumatoid arthritis participants but with no record of any cardiovascular diseases. Methods: On Ninety subjects with no record of considerable CVD but with RA a prospective observational non-experimental studywas performed. Doppler spectral waveform analysis and Ankle Brachial Pressure Index for vascular judgment was performed. Place and Duration: In the Medicine Department of Aziz Fatima Medical and Dental College Faisalabad for one-year duration from April 2020 to April 2021. Results: In this study total 90 of participants were selected out of which 18 were males and 72 were females. The mean age for this study and time period of RA was 62 ±9.01 and 11.8±11.2 years respectively. It was noticed that seventy five percent of the subjects had triphasic waveforms in the Right foot while sixty percent had in the Left foot when examined the posterior tibial or PT artery. In sixty-eight percent of the total participants triphasic waveforms of the Dorsalis Pedis Arteries were found. Biphasic right was present in thirty percent subjects while biphasic left was present in thirty five percent subjects. Biphasic Dorsalis Pedis was found in forty percent participants of both feet. Only one subject was found with discontinuous monophasic PT of both feet. Conclusions: Results show that ABPI index was discovered normal in majority of patients but waveform analysis was found suboptimal or biphasic in total of one-third of the participants. These results indicatethat to find patients with early PAD the judgment of peripheral arterial perfusion should use both modes. Keywords: Rheumatoid arthritis, ankle brachial pressure value, CVD risks hazards, screening.

Doppler Assessment of the Uterine Arteries for the Definition of Pubertal Onset in Girls

Abstract Pelvic ultrasonography (US) is a quick, non-invasive and low-cost method, and doppler analysis facilitates assessment of flow impedance measurement in the uterine vascular tree. The pulsatility index (PI) reflects blood flow impedance in the vessel distal to the sampling point and has been suggested as a parameter to define pubertal development. In order to evaluate the PI and US measurements of uterus and ovaries in girls with different pubertal stages, we performed a cross-sectional study in girls with normal pubertal development. US and Doppler assessed PI of the uterine arteries (defined as the difference between the peak systolic flow and end-diastolic flow divided by the mean maximum flow velocity), endometrial thickness, uterine and ovarian volumes were evaluated. All the US exams were performed with the same equipment by the same radiologist. Clinical data such as the age of menarche, pubarche and thelarche were recorded. Statistical analyses were performed in SPSS, with ANOVA test, Spearman correlation and ROC curve with Youden. One hundred and sixty-nine girls aged 5-16 years (mean 11.3 ± 1.8) who performed two hundred and two pelvic US were included (Tanner 1=20%, Tanner 2=22%, Tanner 3=23%, Tanner 4=17%, Tanner 5=17%). Mean age of thelarche, pubarche and menarche were 11.1 ± 1.8, 10.2 ± 1.2 and 12.2 ± 1.1 years respectively. Prepubertal girls (Tanner 1) had mean PI significantly higher than girls in initial puberty (Tanner 2 and 3 grouped) and in late puberty (Tanner 4 and 5 grouped), respectively 6.5 ± 2.27 vs. 4.15 ± 1.55 vs. 2.82 ± 1.06, p<0.001 for all the comparisons. ROC curve analysis demonstrated that the PI is able to identify the onset of puberty with an area under the curve of 0.80 ± 0.04, P<0.001, and a cutoff point of IP=5.05 presented a sensitivity of 0.77 and a specificity of 0.80 to identify the onset of puberty. When we combined the cutoffs of IP <5.05 plus uterine volume >3.75 cm³, we found a sensitivity of 0.72 and specificity of 0.90 to detect puberty. We identified a strong negative correlation between PI and uterine volume (rs=-0.72, p<0.001) and a moderate negative correlation with endometrial thickness (rs=-0.68, p<0.001) and right (rs=-0.60, p<0.001) and left (rs=-0.59, p<0.001) ovarian volumes. In conclusion, we found a significant reduction of the PI during pubertal development, reflecting a progressive increase in blood flow to the uterus, which can be a valuable non-invasive and highly specific tool to confirm the onset of puberty.

Human Sensing in Reverberant Environments: RF-Based Occupancy and Fall Detection in Ships

In this paper, we explore the possibility of estimating the number of people inside a below-deck ship compartment using the theory of room electromagnetics. Most RF-based occupancy detection solutions focus on residential environments. Confined metallic spaces such in industrial environments are more hostile and exhibit features of a reverberant cavity. The theory of room electromagnetics provides a simple characterization of microwave propagation in such environments. By considering the indoor environment as a lossy cavity, the exponential decay rate of the power-delay profile (PDP), also known as reverberation time (RT), is related to the total absorption inside the room. First, we verify the reverberating nature of the room by measuring the RT at different locations inside the room. The PDPs are calculated from the channel impulse response (CIR) measured using the MIMOSA radio channel sounder. Then, the relation between RT and the number of people inside the room is investigated. We show that it is possible to estimate the number of stationary people with a good accuracy, depending on the number of antennas used. With a success rate of 88%, the estimation error is only one person when 16 spatially averaged PDPs are used. Higher success rates are achievable with more spatial averaging. Moreover, off-the-shelf (OTS) ultra wide band (UWB) devices are used to estimate the number of people inside the same room. Results show that temporal averaging of PDPs can further improve the success rate to 95% when people inside the room are moving. In addition, the detection of a lone person falling to the ground is investigated based on the Doppler analysis of the measured CIRs. It is shown that the Doppler spread in case of a fall has higher peak values compared to normal activities, such as walking and sitting. With the use of a simple Bayes classifier, a fall is detected with 98% accuracy and 100% sensitivity.

Experimental investigation of the spray characteristics for air-less nozzle, internal-mix nozzle and external-mix nozzle

ABSTRACT Spray technology has a widely application in all kinds of industrial field, it is important to investigate the spray characteristics of different nozzles which have a decisive effect on spray area. In this study, Phase Doppler Analyzer is used to measure and compare the spray characteristics of air-less nozzle, internal-mix nozzle and external-mix nozzle under different injection conditions. The results show that the increase of compressed air pressure reduces the SMD of air-assisted spray. The uniformity of the droplets size distribution of internal-mix nozzle is also improved by higher compressed air pressure, while that of external-mix nozzle deteriorates. As the axial distance increases, the Sauter Mean Diameter and uniformity index of all nozzles decrease first and then increase due to the collisions and coalescence of droplets. As the radial distance increases, the Sauter Mean Diameter of spray for the air-less nozzle and internal-mix nozzle decreases, and the uniformity index increases. While the change of the Sauter Mean Diameter and uniformity index for the external-mix nozzle are opposite because air and droplets interact intensely.

In Situ, Rotor-Based Drone Measurement of Wind Vector and Aerosol Concentration in Volcanic Areas

Unmanned aerial vehicles (UAVs), represented by rotor-based drones, are suitable for volcanic observations owing to the advantages of mobility and safety. In this study, vertical profiles of wind and aerosol concentrations at altitudes up to 1000 m around Mt. Sakurajima, one of the most active volcanoes in Japan, were measured in situ using a drone equipped with an ultrasonic anemometer and aerosol sensor. The drone-measured wind profiles were compared with Doppler LiDAR data and analysis values derived from a meteorological model. Drone-measured vertical profiles collected at a vertical speed of 1 m·s−1 (upward and downward) showed strong agreement with the LiDAR observations, as did the averaged values of hovering drone measurements. Obvious vertical wind shear was found by the drone in the vicinity of Mt. Sakurajima. An aerosol sensor was installed on the drone with the capability to measure fine (PM2.5) and coarse particles (PM10) simultaneously; in this manner, volcanic ash and aerosol pollutants around the volcano could be distinguished. Thus, it was proven that drones could be applied to investigate wind conditions and aerosols in situ, even at dangerous locations near active volcanoes.

English

BACKGROUND One of the most common complications of pregnancy is preeclampsia, characterized by abnormal placental development, leading to inadequate uteroplacental blood flow. Doppler ultrasonography can pick up these abnormalities; thus, it is a useful tool to assess fetal outcome. Objective is to calculate the role of colour Doppler (umbilical and middle cerebral artery) in predicting the perinatal outcome. We wanted to evaluate the application of Doppler ultrasound in analysing the blood flow velocity waveform. METHODS This was a cross sectional study carried out between May 2010 - November 2012 in Obstetrics Department, Yenepoya Medical College, Karnataka, among 150 pregnant women with preeclampsia. RESULTS 49.3 % of patients belonged to 25 - 30 years, 58.7 % were primigravida, and 73.3 % and 26.7 % had mild and severe preeclampsia respectively. Patients with increased resistance umbilical artery Doppler - 63.8 % had babies < 2.5 Kg birth weight, 60.9 % Apgar < 7 at 5 minutes of birth and 67.5 % neonatal intensive care unit (NICU) admissions; absent end diastolic flow - all had birth weight < 2 Kg, 90 % Apgar < 7 at 5 minutes, 1 neonatal death and all required NICU admissions; reversal end diastolic flow - 1 neonatal death, all had birth weight < 2.5 Kg, an Apgar < 7 at 5 minutes and required NICU admission. Patients with abnormal Doppler in middle cerebral artery, 46.2 % were low birth weight and had Apgar < 7 at 5 minutes, 50 % required NICU admissions, but no perinatal mortality. CONCLUSIONS Doppler analysis helps in early detection of uteroplacental and fetoplacental changes and to take decisions for early interventions, like administration of steroids for fetal lung maturity and transferring preterm pregnancies to higher centres for better NICU facilities. Umbilical artery Doppler findings are slightly better predictors of adverse perinatal outcome than an abnormal middle cerebral artery. KEYWORDS Doppler, Preeclampsia, Perinatal Outcome, Umbilical Artery, Middle Cerebral Artery