Added value of ratio of cross diameters of the appendix in ultrasound diagnosis of acute appendicitis

BACKGROUND The maximum outer diameter(MOD)of the appendix is an essential parameter for diagnosing acute appendicitis,but there is space for improvement in ultrasound(US)diagnostic performance.AIM To investigate whether combining the ratio of the cross diameters(RATIO)of the appendix with MOD of the appendix can enhance the diagnostic performance of acute appendicitis.METHODS A retrospective study was conducted,and medical records of 233 patients with acute appendicitis and 112 patients with a normal appendix were reviewed.The MOD and RATIO of the appendix were calculated and tested for their diagnostic performance of acute appendicitis,both individually and in combination.RESULTS The RATIO for a normal appendix was 1.32±0.16,while for acute appendicitis it was 1.09±0.07.The cut-off value for RATIO was determined to be≤1.18.The area under the receiver operating characteristic curve(AUC)for diagnosing acute appendicitis using RATIO≤1.18 and MOD>6 mm was 0.870 and 0.652,respectively.There was a significant difference in AUC between RATIO≤1.18 and MOD>6 mm(P<0.0001).When comparing the combination of RATIO≤1.18 and MOD>6 mm with MOD>6 mm alone,the combination showed increased specificity,positive predictive value(PPV),and AUC.However,the sensitivity and negative predictive value decreased.CONCLUSION Combining RATIO of the appendix≤1.18 and MOD>6 mm can significantly improve the specificity,PPV,and AUC in the US diagnosis of acute appendicitis.

An evaluation of ureteral diameter ratio and vesicoureteral reflux index in the treatment of primary vesicoureteral reflux

Objective:Vesicoureteral reflux(VUR)index is a simple,validated tool that reliably predicts significant improvement and spontaneous resolution of primary reflux in children.The aim of this study was to evaluate and compare the ureter diameter ratio(UDR)and VUR index(VURx)of patients treated with endoscopic injection(EI)and ureteroneocystostomy(UNC)methods in the pediatric age group due to primary VUR.Methods:Patients under the age of 18 years old who underwent EI and UNC with the diagnosis of primary VUR between January 2011 and September 2021 were determined as the participants.The UDR was assessed using voiding cystourethrography,and the VURx score was determined prior to treatment based on hospital records included in the study.Results:A total of 255 patients,60(23.5%)boys and 195(76.5%)girls,with a mean age of 76.5(range 13.0e204.0)months,were included in the study.EI was applied to 130(51.0%)patients and UNC was applied to 125(49.0%)patients due to primary VUR.The optimum cut-off for the distal UDR was obtained as 0.17 with sensitivity and specificity of 73.0%and 63.0%,respectively.The positive and negative predictive values were 66.0%and 70.0%,respectively.Conclusion:When the UDR and VURx score are evaluated together for the surgical treatment of primary VUR in the pediatric age group,it is thought that it may be useful in predicting the clinical course of the disease and evaluating surgical treatment options.

Prognostic value of the echocardiographic right/left ventricular end-diastolic diameter ratio in patients with idiopathic pulmonary arterial hypertension

Background Previous studies have shown that an echocardiographic right/left ventricular end-diastolic diameter ratio(RV/LV ratio)≥0.9 is an independent predictor of poor prognosis in patients with acute pulmonary embolism. The prognostic value of the RV/LV ratio in patients with idiopathic pulmonary arterial hypertension(IPAH) is still unknown. Methods We retrospectively enrolled 95 consecutive patients with newly diagnosed IPAH and 16 of them were reevaluated by echocardiography at 3-12 months following targeted therapy.Follow-up data were obtained by telephone interviews and review of the patients’ records.Results The RV/LV ratio was in parallel with the severity of World Health Orgnization(WHO) functional class and mean right atrial pressure.The RV/LV ratio was positively correlated with total pulmonary resistance(P P P 2 saturation(P P = 0.001),weight and absence of targeted therapy were independent predictors of death.No significant changes in the RV/LV ratio before and after targeted therapy were observed. A baseline RV/LV ratio≥0.84 or a further increase in the RV/LV ratio during targeted therapy indicated a poor prognosis. Conclusions The RV/LV ratio helps to assess the severity of IPAH and serves as an independent predictor of prognosis in patients with IPAH.

On the Elastic Vibration Model for High Length-Diameter Ratio Rocket with Attitude Control System

An elastic vibration model for high length diameter ratio spinning rocket with attitude control system which can be used for trajectory simulation is established. The basic theory of elastic dynamics and vibration dynamics were both used to set up the elastic vibration model of rocket body. In order to study the problem more conveniently, the rocket's body was simplified to be an even beam with two free ends. The model was validated by simulation results and the test data.

Effect of Radial Porosity Oscillation on the Thermal Performance of Packed Bed Latent Heat Storage

Owing to its high heat storage capacity and fast heat transfer rate,packed bed latent heat storage(LHS)is considered as a promising method to store thermal energy.In a packed bed,the wall effect can impact the packing arrangement of phase change material(PCM)capsules,inducing radial porosity oscillation.In this study,an actual-arrangement-based three-dimensional packed bed LHS model was built to consider the radial porosity oscillation.Its fluid flow and heat transfer were analyzed.With different cylindrical sub-surfaces intercepted along the radial direction in the packed bed,the corresponding relationships between the arrangement of capsules and porosity oscillation were identified.The oscillating distribution of radial porosity led to a non-uniform distribution of heat transfer fluid(HTF)velocity.As a result,radial temperature distributions and liquid fraction distributions of PCMs were further affected.The effects of different dimensionless parameters(e.g.,tube-to-capsule diameter ratio,Reynolds number,and Stefan number)on the radial characteristics of HTF and PCMs were discussed.The results showed that different diameter ratios correspond to different radial porosity distributions.Further,with an increase in diameter ratio,HTF velocity varies significantly in the near wall region while the non-uniformity of HTF velocity in the center region will decrease.The Reynolds and Stefan numbers slightly impact the relative velocity distribution of the HTF-while higher Reynolds numbers can lead to a proportional improvement of velocity,an increase in Stefan number can promote heat storage of the packed bed LHS system.

Optimization Analysis of the Mixing Chamber and Diffuser of Ejector Based on Fano Flow Model

An improved model to calculate the length of the mixing chamber of the ejector was proposed on the basis of the Fano flow model,and a method to optimize the structures of the mixing chamber and diffuser of the ejector was put forward.The accuracy of the model was verified by comparing the theoretical results calculated using the model to experimental data reported in literature.Variations in the length of the mixing chamber L_(m) and length of the diffuser L_(d) with respect to variations in the outlet temperature of the ejector T_(c),outlet pressure of the ejector p_(c),and the expansion ratio of the pressure of the primary flow to that of the secondary flow p_(g)/p_(e) were investigated.Moreover,variations in L_(m) and L_(d) with respect to variations in the ratio of the diameter of the throat of the motive nozzle to the diameter of the mixing chamber d_(g0)/d_(c3) and ratio of the outlet diameter of the diffuser to the diameter of themixing chamber d_(c)/d_(c3) were investigated.The distribution of flow fields in the ejector was simulated.Increasing L_(m) and d_(c3) reduced T_(c) and p_(c).Moreover,reducing p_(g)/p_(e) or d_(g0)/d_(c3) reduced T_(c) and p_(c).The length of the mixed section L_(m2),which was determined on the basis of the Fano flow model,increased as pg increased and decreased as d_(c3) increased.The mixing length L_(m1),which was considered the primary flow expansion,showed the opposite trend with that of L_(m2).Moreover,Ld increased as p_(g)/p_(e) and d_(c)/d_(c3) increased.When the value of d_(c) was 1.8 to 2.0 times as high as that of dc3,the semi-cone angle of the diffuser ranged between 6°and 12°.At a constant dc/dc3,decreasing T_(c) and pc increased Ld.

A Parametric Approach to the Evaluation of Flexural Strength of Advanced Ceramic or Glass Like Cylindrical Rods at Ambient Temperature

This critical review presents a parametric approach to the evaluation of flexural strength of advanced ceramic or glass like cylindrical rods at ambient temperature.The parameters governing the measurement and evaluation of flexure strengths of glasses and ceramics are detailed with references.The scope for improvement in the existing ASTM STM C-1684 standard is described with a logical rationale and the parameters that need to be addressed are listed and explained.

Quantifying.Associations among Dimensions of Ears and Their Form Factors in Maize(Zea Mays)Using Dimensional Analysis

Ear morphological traits such as volume and shape are important features of maize and the quantitative associations among them can help understand kernel yield determination. 150 mature ears each of 4 maize cultivars were collected from field experiments, and ear length(L), diameter(D), area(S) and volume(V) were recorded for individual ears, kernel weight per ear also recorded for a portion of the examined ears. Following principles of dimensional analysis, 8 theoretical equations of 3 sets,which relate ear higher dimensions to its length and diameter, were developed and parameterized and validated with the field observations. The 3 optimized equations showed that the shape of ears in maize can be featured with 3 dimensionless form factors, namely diameter-to-length ratio(c=D/L), areal form factor(b=S/L/D), and volumetric form factor(a=V/L/D/D). Statistically,all of them were significantly different among cultivars, and a's values varied from 0.582 to 0.612, and b's 0.839-0.868, and c's 0.242-0.308. Volumetric form factor and areal form factor could estimate precisely ear volume and area respectively, but diameter-to-length ratio was not suitable to estimate ear diameter by its length. Ear volume explained almost all variation of ear kernel weight and product L*D*D did the same substantially. Dimensional analysis proved to be promising in understanding relationship among morphological traits of ears in maize. Its application in crop researches should improve our knowledge of the physical properties of crop plants.

BMI, WC, WHtR, VFI and BFI: Which Indictor is the Most Efficient Screening Index on Type 2 Diabetes in Chinese Community Population

Objective Obesity is a major risk factor for type 2 diabetes, many indexes can be used to describes obesity and predict diabetes. This research attempts to identify the best indicator of obesity to screening diabetes in Chinese population. Methods A cross-sectional data of 8121 subjects aged 35-60 years were included in this research belongs to the Diabetes Appropriate Technology Intervention Study. Anthropometric indicators including body weight, height, waist circumferences （WC）, body fat index （BFI） and visceral fat index （VFI） and blood biochemical indicators after an overnight fast [fasting blood glucose, total cholesterol, high-density lipoprotein （HDL） cholesterol, and triacylglycerol] were measured. BMI （body mass index） and Weight to Height Ratio was calculated. Results Subjects with obesity had a higher risk of physician diagnosed diabetes （0R=2.50, 95% CI 1.83-3.43）, new diagnosed diabetes （0R=4.23, 95% Cl 2.91-6.15） and pre-diabetes （0R=1.75, 95% CI 1.31-2.34） compared to those with normal Body mass index （BMI）. There was a significant trend of increased risk of all diabetes status with increased waist circumference （WC）. The waist-to-height ratio （WHtR） yielded the most significant association with new diagnosed diabetes and physician diagnosed diabetes than other indices. Conclusion Central obesity is significantly correlated with diabetes. VFI was most correlated with pre-diabetes while WHtR is an efficient screening index than BMI and WC in Chinese community diabetes screening.

Stress-strain-acoustic responses in failure process of coal rock with different height to diameter ratios under uniaxial compression

Residual coal pillars play an important role in mining the adjacent coal seam safely,managing the gobs and maintaining the stability of abandoned coal mines.The height to diameter ratio(H/D)affects the stability of residual coal pillars.In this study,uniaxial compressive tests of coal specimens with five H/D(2.0,1.5,1.0,0.8 and 0.6)were performed,and the stress,strain and acoustic emission(AE)were monitored.Results show that the uniaxial compressive strength(UCS)and peak strain increase with H/D decreasing.An empirical equation is proposed to calculate the UCS based on the H/D.The AE activities during coal failure process can be separated into four periods.The span of quiet period and rapid decline period shorten with H/D decreasing.The smaller the H/D is,the more complicated the failure characteristics of coal will be.The failure form of coal with H/D of 2.0,1.5,and 1.0 is primarily shear failure,while splitting failure along the axial direction is the mainly mode when H/D is 0.8 or 0.6.The initiation,expansion,aggregation and connection of micro-cracks can be reflected by the real-time spatial evolution of AE event points.

The Growth of Latex Particles during the VAc/BA Copolymerization

The semi-continuous seeded emulsion eopolymerization of vinyl acetate and butyl acrylate was carried out with hydroxyethyl cellulose as a colloid stabilizer. The morphology of the latex particle and the relationship between the reaction time and the average particle diameter and/or the conversion ratio during the polymerization were invstiguted. The experimental results shaw that the morphology of the latex particle possesses the stable sterie construction. In the seeded polymerizution, the average particle diameter of latex decreased while the conversion ratio increased. At the second term of the emulsion copolymerization （the growth stage of particle size）, the latex particle average diameter increased with copolymerization continuously, but the instantaneous conversation ratio was not large, so it was very necessaO to properly prolong the time during the holding temperature stage.

Association of Obesity and Kidney Function Decline among Non-Diabetic Adults with eGFR >60 ml/min/1.73m²: Results from the Multi-Ethnic Study of Atherosclerosis (MESA)

Background: Obesity is associated with higher end-stage renal disease incidence, but associations with earlier forms of kidney disease remain incompletely characterized. Methods: We studied the association of body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR) with rapid kidney function decline and incident chronic kidney disease in 4573 non-diabetic adults with eGFR ≥ 60 ml/min/1.73m2 at baseline from longitudinal Multi-Ethnic Study of Atherosclerosis cohort. Kidney function was estimated by creatinine and cystatin C. Multivariate analysis was adjusted for age, race, baseline eGFR, and hypertension. Results: Mean age was 60 years old, BMI 28 kg/m2, baseline eGFRCr 82 and eGFRCys 95 ml/min/1.73m2. Over 5 years of follow up, 25% experienced rapid decline in renal function by eGFRCr and 22% by eGFRCys. Incident chronic kidney disease (CKD) developed in 3.3% by eGFRCys, 11% by eGFRCr, and 2.4% by both makers. Compared to persons with BMI 25, overweight (BMI 25 - 30) persons had the?lowest risk of rapid decline by eGFRCr (0.84, 0.71 - 0.99). In contrast, higher BMI categories were associated with stepwise higher odds of rapid decline by eGFRCys, but remained significant only when BMI ≥ 35 kg/m2 (1.87, 1.41 - 2.48). Associations of BMI with incident CKD were insignificant after adjustment. Large WC and WHR were associated with increased risk of rapid decline only by eGFRCys, and of incident CKD only when defined by both filtration markers. Conclusions: Obesity may be a risk factor for kidney function decline, but associations vary by filtration marker used.

Numerical Study of an Oscillating Smaller Cylinder in the Wake of an Upstream Larger Cylinder

A numerical study of flow around two tandem cylinders with unequal diameters was carried out. The upstream larger cylinder was fixed and the downstream smaller cylinder was allowed to oscillate in the transverse direction only. Comparisons of the experimental and numerical results were made to investigate the effects of the gap ratio on the maximum vibration amplitude and vortex shedding frequency. The results showed that the vibration response of the smaller cylinder was significantly affected by the presence of the upstream larger cylinder, and resulted in greatly reduced vibration amplitudes. With an increasing gap ratio, the vibration amplitude increased. However, the magnitude was lower than that corresponding to a single cylinder (with the same diameter as that of the downstream smaller cylinder) under the same flow conditions.

Growth of Douglas-fir （Pseudotsuga menziesii （Mirb.） Franco） in the Region of Yundola Training and Experimental Forest Range, Bulgaria

The aim of the article was to study the growth of Douglas-fir plantations in the region of the Training Experimental Forest Enterprise, Yundola （Central South Bulgaria）. The study sites were three Douglas-fir plantations, ranging between 50 and 55 years of age at altitudinal range between 1,400 m and 1,600 m above sea level （masl）. The mean height, diameter at breast height, site class, stem volume as well as the mechanical resistance （H/D ratio） of Douglas-fir were measured for each plantation. The results showed that Douglas-fir had the best height growth of the studied plantations on slope facing South at altitude 1,600 masl and Douglas-fir with age 55 years old reached a mean height of 32.4 m. The average diameter at breast height of the studied plantations reaches approximately 30 cm, which shows that they are suitable for large scale wood harvesting. The average stem volume of Douglas-fir in the observed plantations up to age of 55 is within the range of 400-600 m3/ha, with an average annual volume increment from 7 m3/ha to 12 m3/ha each year. The high index of mechanical resistance （H/D ratio） indicated a risk for abiotic damages, which implicated the need for the immediate implementation of felling.

Effect of channel diameter on magneto-thermal conversion ratio and consistency of each strand in a multi-strand induction heating tundish

The electromagnetic,flow,heat transfer and inclusions motion model of the channel-type induction heating(IH)tundish was established,and the effect of the channel diameter on the metallurgical behavior of the tundish was studied.The results show that the magnetic field in the channel of the IH tundish tends to concentrate on the surface layer and the side near the coil.As the channel diameter is increased from 100 to 180 mm,the maximum value of magnetic flux density in the channel decreases by 0.125 T,and the maximum value of electromagnetic force decreases by 11.83×10^(5) N m^(-3);however,the off-center distance of magnetic field increases by 9.4 mm,and the Joule heat in the channel decreases by 1004 kW,which leads to the reduction in temperature rising rate of the tundish from 1.41 to 0.59 K min^(-1).When the channel diameter is 100,140 and 180 mm,the maximum velocity at the channel exit before heating is 0.59,0.29 and 0.18 m s^(-1),and after heating for 1800 s,it is 1.52,1.12 and 0.92 m s^(-1),respectively.In addition,the total inclusions escape ratio after heating for 1800 s with a channel diameter of 140 mm can be reduced by 12.39% compared to that before heating,and the maximum difference of escape ratios for each strand is only 4.51% and 5.32% before heating and after heating for 1800 s,respectively.Compared with the channel diameters of 100 and 180 mm,the channel diameter of 140 mm is more favorable to improve the metallurgical effect of the IH tundish.

Age-related changes in the ratio of Type I/III collagen and fibril diameter in mouse skin

The content of type I collagen(COL-I)and type III collagen(COL-III)and the ratio between them not only affect the skin elasticity and mechanical strength,but also determine the fibril diameter.In this research,we investigated the age-related changes in COL-I/COL-III ratio with their formed fibril diameter.The experimental result was obtained from high performance liquid chromatography-mass spectrometer,hydroxyproline determination,picrosirius red staining and transmission electron microscopes(TEM),respectively.The result indicated that the COL-I/COL-III ratio in mouse skin increased with aging.From the 0th to 9th week,the COL-I/COLIII ratio increased from 1.3:1 to 4.5:1.From the 9th to the 18th week,it remained between 4.5:1 and 4.9:1.The total content of COL-I and COL-III firstly increased and then decreased with aging.The TEM result showed that the fibril diameter increased with aging.From the 0th to 9th week,the average fibril diameter increased from 40 to 112 nm;From the 9th to 18th weeks,it increased from 112 to 140 nm.After the 9th week.The fibril diameter showed obvious uneven distribution.Thus,the COL-I/COLIII ratio was proportional to the fibril diameter,but inversely proportional to the uniformity of fibril diameter.

Platelet count/spleen diameter ratio to predict esophageal varices in Mexican patients with hepatic cirrhosis

AIM: To validate whether the platelet count/spleen size ratio can be used to predict the presence of esophageal varices in Mexican patients with hepatic cirrhosis.

A criterion for flow mechanisms through vertical sharp-edged orifice and model for the orifice discharge coefficient

According to the experimental data of the orifice discharge coefficient for the flow through a vertical sharp-edged orifice obtained in the previous study of this work,a theoretical criterion for flow mechanisms of small orifice（viz.thick-walled orifice and nozzle） and large orifice（viz.thin-walled orifice） was proposed based on the ratio of orifice diameter to plate thickness.It can help explain the dissipation of the mechanical energy loss in the flow process for the two flow mechanisms under different operating regimes.The main parameters such as orifice diameter,plate thickness and liquid head were correlated,and a semi-empirical model for orifice coefficient and an empirical model with high precision at the stable region were developed.

Performance of waist circumference relative to BMI in predicting risk of obesity and hypertension among affluent Indian adults

In view of the fact that Asians have higher abdominal fat at lower levels of body mass index (BMI), measures of abdominal adiposity such as waist circumference (WC) and waist to hip ratio (WHR) were investigated as predictors of hypertension. Data on BMI, WC, WHR and blood pressure (BP) were recorded through a cross-sectional study on 419 urban adults (210 men and 209 women;aged 30-60 years) in Pune, India. Abdominal obesity was higher among women than men (35.9% vs. 32.4%). However, age adjusted mean systolic BP (124.3 ± 15.1 mmHg vs. 114.7 ± 17.2 mmHg), diastolic BP (82.9 ± 10.5 mmHg vs. 76.4 ± 10.7 mmHg) and prevalence of hypertension (34.3% vs. 21.5%) was significantly higher (p < 0.01) among men than among women. Although both WC and WHR increased with increase in BMI, correlation coefficient of BMI with WC was significantly (p < 0.01) higher than that with WHR in both sexes, suggesting that WC could be better for assessing adiposity. In men, odds ratio [OR (95% CI) = 2.19 (1.08-4.45)] for hypertension was significant (p < 0.05) only for those in highest tertile of WC while it was significant (p < 0.01) even in the middle tertile in case of women [8.24 (2.67-25.43) for higher and 5.71 (1.82-17.89) for middle tertile]. Optimal cutoff for identifying obesity and hypertension showed significant (p < 0.01) area under curve (AUC) and sensitivity for WC than WHR in both sexes. The risk cutoffs were lower compared to those proposed by the World Health Organization especially for men, but were comparable with reported Asian studies. Thus, it was evident that WC performed better than BMI and WHR for assessing the risk of hypertension and may be used as a simple, convenient and inexpensive screening tool in epidemiological studies.

Can platelet count/spleen diameter ratio be used for cirrhotic children to predict esophageal varices?

AIM To determine the laboratory and radiologic parameters, including the platelet count(PC)-to-spleen diameter(SD) ratio as a non-invasive marker that may predict the presence of esophageal varices(EV) in children with cirrhosis.METHODS Eighty-nine patients with cirrhosis, but without a history of variceal bleeding were prospectively included. The children were grouped into 6-12 and 12-18 years of age groups. These groups were also divided into 2 subgroups(presence and absence of EV). All of the patients underwent a complete biochemical and radiologic evaluation. The PC(n/mm^3)-to-SD(mm) ratio was calculated for each patient. RESULTS Sixty-nine of 98(70.4%) patients had EV. The presence of ascites in all age groups was significantly associatedwith the presence of EV. There were no differences in serum albumin levels, PC, SD and the PC-to-SD ratio between the presence and absence of EV groups in both age groups(P > 0.05). CONCLUSION Laboratory and radiologic parameters, including the PC-to-SD ratio as a non-invasive marker(except for the presence of ascites), was inappropriate for detecting EV in children with cirrhosis.