scholarly journals Design and Experiment of Assistive Mechanism for Adjustment of Transrectal Ultrasound Probe

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Jin-Gang Jiang ◽  
Hui Zuo ◽  
Yong-De Zhang ◽  
Zhi-Yuan Huang ◽  
Xiao-Wei Guo ◽  
...  
Keyword(s):  
Elevation Angle ◽  
Transrectal Ultrasound ◽  
Maximum Error ◽  
Relative Standard Error ◽  
Ultrasound Probe ◽  
Ultrasonic Probe ◽  
Center Point ◽  
Relative Standard ◽  
Point Motion ◽  
Posture Adjustment

Transrectal ultrasound prostate biopsy is the most commonly used method for the diagnosis of prostate cancer. During the operation, the doctor needs to manually adjust the ultrasound probe for repeated adjustments, which is difficult to ensure the efficiency, accuracy, and safety of the operation. This paper presents a passive posture adjusting mechanism of transrectal ultrasound probe. The overall mechanism has 7 degrees of freedom, consisting of a position adjustment module, a posture adjustment module, and an ultrasonic probe rotation and feed module. In order to achieve the centering function, the posture adjustment module is designed based on the double parallelogram. Centering performance is verified based on SimMechanics, and remote center point error of physical prototypes is evaluated. The maximum error of the azimuth remote center point motion and the maximum error of the remote center point motion of the ultrasonic probe are 4 mm and 3.4 mm, respectively, which are less than the anus that can withstand 6 mm. Meanwhile, the analysis of measurement error shows that the random error correlation is weak in different directions, the systematic error confidence intervals of azimuth and elevation angle are less than 2.5 mm, and the maximum relative fixed point error and the maximum relative standard error are 14.73% and 14.98%, respectively. The simulation and testing results have shown the effectiveness and reliability of the propose mechanism.

DESIGN AND PERFORMANCE EVALUATION OF PASSIVE INTERLOCKING POSTURE ADJUSTMENT MECHANISM FOR TRANSRECTAL ULTRASOUND PROBE

2019 ◽  
Vol 19 (07) ◽  
pp. 1940035 ◽  
Author(s):  
JINGANG JIANG ◽  
ZHAOWEI MIN ◽  
YONGDE ZHANG ◽  
XIAOWEI GUO ◽  
YONG XU
Keyword(s):  
Performance Evaluation ◽  
Transrectal Ultrasound ◽  
Ultrasound Probe ◽  
Probe Position ◽  
Ultrasonic Probe ◽  
Adjustment Mechanism ◽  
Physical Prototype ◽  
Braking Torque ◽  
And Performance ◽  
Posture Adjustment

In the current prostate biopsy procedure, it is necessary for the doctor to hold the ultrasonic probe during the entire process. This increases the fatigue degree of the doctor, and the motion of the ultrasonic probe is more likely to cause damage to the anus of the patient. A medical device that can assist doctors in prostate scans and biopsy puncture devices was developed. We focused on the passive interlocking transrectal ultrasonic probe posture adjustment mechanism. Based on the posture adjustment mechanism, a passive interlocking transrectal ultrasound probe position and posture adjustment mechanism capable of assisting the doctor in prostate scanning and puncture intervention was designed. The passive interlocking posture adjustment mechanism with a seven-degree-of-freedom (DOF) interlocking mechanism was designed and can meet the requirements of doctors. The physical prototype of the passive interlocking transrectal ultrasonic probe posture adjustment mechanism was developed and commissioned. The locking torque and braking torque of the mechanism were measured. The results showed that the ultrasonic probe can achieve reliable locking and effectively meet the operation requirements.

scholarly journals Lidar arc scan uncertainty reduction through scanning geometry optimization

2016 ◽  
Vol 9 (4) ◽  
pp. 1653-1669 ◽  
Author(s):  
Hui Wang ◽  
Rebecca J. Barthelmie ◽  
Sara C. Pryor ◽  
Gareth. Brown
Keyword(s):  
Theoretical Model ◽  
Wind Speed ◽  
Wind Energy ◽  
Turbulence Intensity ◽  
Wind Direction ◽  
Energy Production ◽  
Elevation Angle ◽  
Relative Standard Error ◽  
Power Performance ◽  
Relative Standard

Abstract. Doppler lidars are frequently operated in a mode referred to as arc scans, wherein the lidar beam scans across a sector with a fixed elevation angle and the resulting measurements are used to derive an estimate of the n minute horizontal mean wind velocity (speed and direction). Previous studies have shown that the uncertainty in the measured wind speed originates from turbulent wind fluctuations and depends on the scan geometry (the arc span and the arc orientation). This paper is designed to provide guidance on optimal scan geometries for two key applications in the wind energy industry: wind turbine power performance analysis and annual energy production prediction. We present a quantitative analysis of the retrieved wind speed uncertainty derived using a theoretical model with the assumption of isotropic and frozen turbulence, and observations from three sites that are onshore with flat terrain, onshore with complex terrain and offshore, respectively. The results from both the theoretical model and observations show that the uncertainty is scaled with the turbulence intensity such that the relative standard error on the 10 min mean wind speed is about 30 % of the turbulence intensity. The uncertainty in both retrieved wind speeds and derived wind energy production estimates can be reduced by aligning lidar beams with the dominant wind direction, increasing the arc span and lowering the number of beams per arc scan. Large arc spans should be used at sites with high turbulence intensity and/or large wind direction variation.

scholarly journals Lidar arc scan uncertainty reduction through scanning geometry optimization

2015 ◽  
Vol 8 (10) ◽  
pp. 10429-10471
Author(s):  
H. Wang ◽  
R. J. Barthelmie ◽  
S. C. Pryor ◽  
G. Brown
Keyword(s):  
Theoretical Model ◽  
Wind Speed ◽  
Wind Energy ◽  
Turbulence Intensity ◽  
Wind Direction ◽  
Energy Production ◽  
Elevation Angle ◽  
Relative Standard Error ◽  
Power Performance ◽  
Relative Standard

Abstract. Doppler lidars are frequently operated in a mode referred to as arc scans, wherein the lidar beam scans across a sector with a fixed elevation angle and the resulting measurements are used to derive an estimate of the n minute horizontal mean wind velocity (speed and direction). Previous studies have shown that the uncertainty in the measured wind speed originates from turbulent wind fluctuations and depends on the scan geometry (the arc span and the arc orientation). This paper is designed to provide guidance on optimal scan geometries for two key applications in the wind energy industry: wind turbine power performance analysis and annual energy production. We present a quantitative analysis of the retrieved wind speed uncertainty derived using a theoretical model with the assumption of isotropic and frozen turbulence, and observations from three sites that are onshore with flat terrain, onshore with complex terrain and offshore, respectively. The results from both the theoretical model and observations show that the uncertainty is scaled with the turbulence intensity such that the relative standard error on the 10 min mean wind speed is about 30 % of the turbulence intensity. The uncertainty in both retrieved wind speeds and derived wind energy production estimates can be reduced by aligning lidar beams with the dominant wind direction, increasing the arc span and lowering the number of beams per arc scan. Large arc spans should be used at sites with high turbulence intensity and/or large wind direction variation when arc scans are used for wind resource assessment.

scholarly journals Population Pharmacokinetics of Fluconazole in Young Infants

2008 ◽  
Vol 52 (11) ◽  
pp. 4043-4049 ◽  
Author(s):  
K. C. Wade ◽  
D. Wu ◽  
D. A. Kaufman ◽  
R. M. Ward ◽  
D. K. Benjamin ◽  
...  
Keyword(s):  
Fixed Effects ◽  
Compartment Model ◽  
Volume Of Distribution ◽  
Relative Standard Error ◽  
Data Set ◽  
Mixed Effect ◽  
Young Infants ◽  
Relative Standard ◽  
Population Pk ◽  
The Impact

ABSTRACT Fluconazole is being increasingly used to prevent and treat invasive candidiasis in neonates, yet dosing is largely empirical due to the lack of adequate pharmacokinetic (PK) data. We performed a multicenter population PK study of fluconazole in 23- to 40-week-gestation infants less than 120 days of age. We developed a population PK model using nonlinear mixed effect modeling (NONMEM) with the NONMEM algorithm. Covariate effects were predefined and evaluated based on estimation precision and clinical significance. We studied fluconazole PK in 55 infants who at enrollment had a median (range) weight of 1.02 (0.440 to 7.125) kg, a gestational age at birth (BGA) of 26 (23 to 40) weeks, and a postnatal age (PNA) of 2.3 (0.14 to 12.6) weeks. The final data set contained 357 samples; 217/357 (61%) were collected prospectively at prespecified time intervals, and 140/357 (39%) were scavenged from discarded clinical specimens. Fluconazole population PK was best described by a one-compartment model with covariates normalized to median values. The population mean clearance (CL) can be derived for this population by the equation CL (liter/h) equals 0.015 · (weight/1)0.75 · (BGA/26)1.739 · (PNA/2)0.237 · serum creatinine (SCRT)−4.896 (when SCRT is >1.0 mg/dl), and using a volume of distribution (V) (liter) of 1.024 · (weight/1). The relative standard error around the fixed effects point estimates ranged from 3 to 24%. CL doubles between birth and 28 days of age from 0.008 to 0.016 and from 0.010 to 0.022 liter/kg/h for typical 24- and 32-week-gestation infants, respectively. This population PK model of fluconazole discriminated the impact of BGA, PNA, and creatinine on drug CL. Our data suggest that dosing in young infants will require adjustment for BGA and PNA to achieve targeted systemic drug exposures.

Determination of total antioxidant capacity of milk by CUPRAC and ABTS methods with separate characterisation of milk protein fractions

2015 ◽  
Vol 82 (2) ◽  
pp. 177-184 ◽  
Author(s):  
Sema Demirci Çekiç ◽  
Aslı Demir ◽  
Kevser Sözgen Başkan ◽  
Esma Tütem ◽  
Reşat Apak
Keyword(s):  
Antioxidant Capacity ◽  
Total Antioxidant Capacity ◽  
Milk Protein ◽  
Skim Milk ◽  
Protein Fractions ◽  
Relative Standard Error ◽  
Antioxidant Power ◽  
Antioxidant Capacities ◽  
Relative Standard ◽  
Total Antioxidant

Most milk-applied antioxidant assays in literature are based on the isolation and quantification of individual antioxidative compounds, whereas total antioxidant capacity (TAC) gives a more holistic picture due to cooperative action of antioxidants. Recently, the cupric reducing antioxidant capacity (CUPRAC) method has been modified to measure the antioxidant capacities of thiol-containing proteins, where the classical ammonium acetate buffer – that may otherwise precipitate proteins– was replaced with concentrated urea buffer (able to expose embedded thiol groups of proteins to oxidative attack) adjusted to pH 7.0. Thus, antioxidant capacity of milk was investigated with two competing TAC assays, namely CUPRAC and ABTS (2,2′-azinobis(3-ethylbenzothiazoline-6-sulphonic acid))/persulphate, because only these assays were capable of evaluating protein contribution to the observed TAC value. As milk fat caused turbidity, experiments were carried out with skim milk or defatted milk samples. To determine TAC, modified CUPRAC method was applied to whole milk, separated and redissolved protein fractions, and the remaining liquid phase after necessary operations. Both TAC methods were investigated for their dilution sensitivity and antioxidant power assessment of separate milk fractions such as casein and whey. Proteins like β-lactoglobulin and casein (but not simple thiols) exhibited enhanced CUPRAC reactivity with surfactant (SDS) addition. Addition of milk protein fractions to whole skim milk produced significant ‘negative-biased’ deviations (up to −26% relative standard error) from TAC absorbance additivity in the application of the ABTS method, as opposed to that of the CUPRAC method less affected by chemical deviations from Beer's law thereby producing much smaller deviations from additivity (i.e. the property of additivity is valid when the measured TAC of a mixture is equal to the sum of individual antioxidant capacities of its constituents).

Influence of transrectal ultrasound probe on prostate cancer detection in transrectal ultrasound-guided sextant biopsy of prostate

Urology ◽  
2004 ◽  
Vol 64 (3) ◽  
pp. 532-536 ◽  
Author(s):  
Roger Paul ◽  
Christian Korzinek ◽  
Ulrike Necknig ◽  
Thomas Niesel ◽  
Michael Alschibaja ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Cancer Detection ◽  
Transrectal Ultrasound ◽  
Ultrasound Probe ◽  
Ultrasound Guided ◽  
Prostate Cancer Detection ◽  
Sextant Biopsy

Peroxidase Mimic Activities of Copper Selenide (CuSe) Nanoplates for Sensing H2O2 and L-Cysteine

2020 ◽  
Vol 20 (9) ◽  
pp. 5369-5375
Author(s):  
Bai Maojuan ◽  
Xu Chengcheng ◽  
Huang Xuanye ◽  
Liu Yanan ◽  
Wan Jun
Keyword(s):  
Electron Microscopy ◽  
Detection Limit ◽  
Energy Dispersive Spectrometer ◽  
Catalytic Efficiency ◽  
Relative Standard Error ◽  
Colorimetric Determination ◽  
Peroxidase Mimic ◽  
Biomedical Analysis ◽  
X Ray ◽  
Relative Standard

Compared with natural enzymes, artificial mimic enzymes have been widely studied for their high stability and cost effectiveness. In this study, CuSe nanoplates as a simulated enzyme which does not contain precious metals, has peroxidase activity. CuSe nanoplates were prepared and characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray energy dispersive spectrometer (EDS). Kinetic studies show that CuSe nanoplates exhibits a higher affinity for 3,3′,5,5′-teramethylbenzidine (TMB) than horseradish peroxidase (HRP). The rapid colorimetric determination of H2O2 and L-cysteine were developed based on the catalytic efficiency. The linear range of detection for H2O2 is 5.0×10−6~8.0×10−5 M, and the detection limit is 2.9×10−6 M, while the relative standard error is less than 5%. In addition, L-cysteine was detected with a detection limit of 0.2×10−6 M. The good selectivity of the determination to H2O2 and L-cysteine in aqueous solution was also achieved. CuSe nanoplates as a simulated enzyme for sensor applications would be used in environmental monitoring and biomedical analysis.

scholarly journals Review and Mechanism of the Thickness Effect of Solid Dielectrics

Nanomaterials ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2473
Author(s):  
Liang Zhao ◽  
Chun Liang Liu
Keyword(s):  
Physical Mechanism ◽  
Breakdown Strength ◽  
Power Relation ◽  
Thickness Effect ◽  
Power Exponent ◽  
Relative Standard Error ◽  
Dielectric Thickness ◽  
Relative Standard ◽  
Different Types ◽  
Solid Dielectrics

The thickness effect of solid dielectrics means the relation between the electric breakdown strength (EBD) and the dielectric thickness (d). By reviewing different types of expressions of EBD on d, it is found that the minus power relation (EBD = E1d−a) is supported by plenty of experimental results. The physical mechanism responsible for the minus power relation of the thickness effect is reviewed and improved. In addition, it is found that the physical meaning of the power exponent a is approximately the relative standard error of the EBD distributions in perspective of the Weibull distribution. In the end, the factors influencing the power exponent a are discussed.

Use of the Transrectal Ultrasound Probe in Aspiration and Drainage in Pediatric Patients: A Retrospective Observational Study

2019 ◽  
Vol 30 (6) ◽  
pp. 908-914
Author(s):  
Walid Mabrouk Mubarak ◽  
Natasha Sheikh ◽  
Philip John ◽  
Michael J. Temple ◽  
Joao G. Amaral ◽  
...  
Keyword(s):  
Observational Study ◽  
Pediatric Patients ◽  
Transrectal Ultrasound ◽  
Retrospective Observational Study ◽  
Ultrasound Probe

scholarly journals Improvement of NIR models for quality parameters of leech and earthworm medicines using outlier multiple diagnoses

2017 ◽  
Vol 11 (01) ◽  
pp. 1750009 ◽  
Author(s):  
Chunyan Wu ◽  
Jiashan Chen ◽  
Mengru Li ◽  
Yongjiang Wu ◽  
Xuesong Liu
Keyword(s):  
Near Infrared ◽  
Nir Spectroscopy ◽  
Principal Component ◽  
Solid Content ◽  
Detection Methods ◽  
Soluble Solid Content ◽  
Relative Standard Error ◽  
Diffuse Reflection Spectroscopy ◽  
Nondestructive Technique ◽  
Relative Standard

Leeches and earthworms are the main ingredients of Shuxuetong injection compositions, which are natural biomedicines. Near infrared (NIR) diffuse reflection spectroscopy has been used for quality assurance of Chinese medicines. In the present work, NIR spectroscopy was proposed as a rapid and nondestructive technique to assess the moisture content (MC), soluble solid content (SSC) and hypoxanthine content (HXC) of leeches and earthworms. This study goal was to improve NIR models for accurate quality control of leech and earthworm using outlier multiple diagnoses (OMD). OMD was composed of four outlier detection methods: spectrum outlier diagnostic (MD), leverage diagnostic (LD), principal component scores diagnostic (PCSD) and factor loading diagnostic (FLD). Conventional outlier diagnoses (MD, LD) and OMD were compared, and the best NIR models were those based on OMD. The correlation coefficients ([Formula: see text]) for leech were 0.9779, 0.9616 and 0.9406 for MC, SSC and HXC, respectively. The values of relative standard error of prediction (RSEP) for leech were 2.3%, 5.1% and 9.0% for MC, SSC and HXC, respectively. The values of [Formula: see text] for earthworm were 0.9478, 0.9991 and 0.9605 for MC, SSC and HXC, respectively. The values of RSEP for earthworm were 8.8%, 2.4% and 12% for MC, SSC and HXC, respectively. The performance of the NIR models was certainly improved by OMD.

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