AIM:To quantitatively measure ocular morphological parameters of guinea pig with Python technology.METHODS:Thirty-six eyeballs of eighteen 3-weekold guinea pigs were measured with keratometer and photographed to obtai...AIM:To quantitatively measure ocular morphological parameters of guinea pig with Python technology.METHODS:Thirty-six eyeballs of eighteen 3-weekold guinea pigs were measured with keratometer and photographed to obtain the horizontal,coronal,and sagittal planes respectively.The corresponding photo pixels-actual length ratio was acquired by a proportional scale.The edge coordinates were identified artificially by ginput function.Circle and conic curve fitting were applied to fit the contour of the eyeball in the sagittal,coronal and horizontal view.The curvature,curvature radius,eccentricity,tilt angle,corneal diameter,and binocular separation angle were calculated according to the geometric principles.Next,the eyeballs were removed,canny edge detection was applied to identify the contour of eyeball in vitro.The results were compared between in vivo and in vitro.RESULTS:Regarding the corneal curvature and curvature radius on the horizontal and sagittal planes,no significant differences were observed among results in vivo,in vitro,and the keratometer.The horizontal and vertical binocular separation angles were 130.6°±6.39°and 129.8°±9.58°respectively.For the corneal curvature radius and eccentricity in vivo,significant differences were observed between horizontal and vertical planes.CONCLUSION:The Graphical interface window of Python makes up the deficiency of edge detection,which requires too much definition in Matlab.There are significant differences between guinea pig and human beings,such as exotropic eye position,oblique oval eyeball,and obvious discrepancy of binoculus.This study helps evaluate objectively the ocular morphological parameters of small experimental animals in emmetropization research.展开更多
Point-of-care ultrasound has been increasingly used in evaluating shocked patients including the measurement of inferior vena cava(IVC) diameter. Operators should standardize their technique in scanning IVC. Relativec...Point-of-care ultrasound has been increasingly used in evaluating shocked patients including the measurement of inferior vena cava(IVC) diameter. Operators should standardize their technique in scanning IVC. Relativechanges are more important than absolute numbers. We advise using the longitudinal view(B mode) to evaluate the gross collapsibility, and the M mode to measure the IVC diameter. Combining the collapsibility and diameter size will increase the value of IVC measurement. This approach has been very useful in the resuscitation of shocked patients, monitoring their fluid demands, and predicting recurrence of shock. Pitfalls in measuring IVC diameter include increased intra-thoracic pressure by mechanical ventilation or increased right atrial pressure by pulmonary embolism or heart failure. The IVC diameter is not useful in cases of increased intra-abdominal pressure(abdominal compartment syndrome) or direct pressure on the IVC. The IVC diameter should be combined with focused echocardiography and correlated with the clinical picture as a whole to be useful.展开更多
The optical diffraction is a major means of minute diameter measurements. Since the light intensity of the diffraction fringe, mainly distributed in the central bright stripes, and that will lead to a relatively low S...The optical diffraction is a major means of minute diameter measurements. Since the light intensity of the diffraction fringe, mainly distributed in the central bright stripes, and that will lead to a relatively low SNR for the signal of the senior stripes. The traditional dark stripes extraction algorithm affected greatly by the noise. So this paper presents an algorithm that could effectively eliminate the gross errorcaused by the noise. Than by curve fitting the local signal of the diffraction pattern with the least square principle, the system could achieve a high measurement precision.展开更多
AIM:To measure in vitro diameter of imitational varices using a self-made endoscopic scale and confirm its accuracy and clinical feasibility.METHODS:A catheter was introduced into the endoscopeaccessory channel and at...AIM:To measure in vitro diameter of imitational varices using a self-made endoscopic scale and confirm its accuracy and clinical feasibility.METHODS:A catheter was introduced into the endoscopeaccessory channel and attached to a zebra wire guide that was used as a stylet.The wire guide was fixed onto the tip of the catheter by a soft and thin string.By gently advancing the stylet into the catheter,the width of the opening loop at the tip of the endoscope approximated the diameter of the imitational varices.Measurements performed in vitro using this self-made endoscopic ruler were compared to measurements of simulative varices.RESULTS:At the handle,the sleeve moving distance ranged from 5 to 14 mm.There was no obvious proportional relationship between the sleeve movement distance and endoscopic measurement ruler.The results indicated that the gap between the endoscopic measurement and actual measurement of the object size tended to close.The in vitro measurement of the diameter of the simulative varices showed that the two kinds of measuring methods were not significantly different with respect to their accuracy(P=0.8499).CONCLUSION:In vitro experiments confirmed that using a self-designed endoscopic ruler to measure the diameter of simulative varices was objective,accurate and feasible.展开更多
Forest structure analysis is important for understanding the properties and development of a forest community,and its outcomes can be influenced by how trees are measured in sampled plots.Although there is a general c...Forest structure analysis is important for understanding the properties and development of a forest community,and its outcomes can be influenced by how trees are measured in sampled plots.Although there is a general consensus on the height at which tree diameter should be measured[1.3 m:diameter at breast height(DBH)],the minimum measureddiameter(MMD)often varies in different studies.In this study,we assumed that the outcomes of forest structure analysis can be influenced by MMD and,to this end,we applied g(r)function and stand spatial structural parameters(SSSPs)to investigate how different MMDs affect forest spatial structure analysis in two pine-oak mixed forests(30 and 57 years old)in southwest China and one old-growth oak forest(>120years old)from northwest China.Our results showed that 1)MMD was closely related to the distribution patterns of forest trees.Tree distribution patterns at each observational scale(r=0-20 m)tended tobecome random as the MMD increased.The older the community,the earlier this random distribution pattern appeared.2)As the MMD increased,neighboring trees became more regularly distributed around a reference tree.In most cases,however,nearest neighbors of a reference tree were randomly distributed.3)Tree species mingling decreased with increasing diameter,but it decreased slowly in older forests.4)No correlations can be found between individual tree size differentiation and MMD.We recommend that comparisons of spatial structures between communities would be more effective if using a unified MMD criterion.展开更多
Based on laser-scanned measuring technology, a met ho d of on-line dynamic non-contact measurement and feedback control of processin g dimension, i.e. the double edges laser-scanned large diameter on-line dynami c mea...Based on laser-scanned measuring technology, a met ho d of on-line dynamic non-contact measurement and feedback control of processin g dimension, i.e. the double edges laser-scanned large diameter on-line dynami c measurement and control system is presented, which can be used to measure diam eter in large-scale machine part processing. In this paper, the working princip le, overall structure and microcomputer real-time control and data processing s ystem of the system are discussed in detail, the method of double edges scanned large diameter dimension measurement and control is theoretically analyzed, its possibility has been verified by experiments of lathing large diameters machine parts by a vertical lathe. The system adopts the measuring scheme of double edge s laser-scanned combined with grating displacement measurement. The two edges c haracteristic information of the measured diameter is given by the double edges laser-scanned measuring system, the non-contact measurement of large diameter dimension is realized to combine with the grating displacement measuring systems . The main controller gives out feedback control signal by means of measured res ults, and controls advance and retreat of lathe tool by the servo-control syste m of a vertical lathe to realize on-line dynamic non-contact measurement and c ontrol in processing.展开更多
An automatic method able to recognize a presented section through the biparietal plane of the fetal head and a section through the fetal femur in ultrasound images is developed. Once the correct anatomical section for...An automatic method able to recognize a presented section through the biparietal plane of the fetal head and a section through the fetal femur in ultrasound images is developed. Once the correct anatomical section for measurement is identified by the machine, the placement of the measurement calipers is automatically determined by fitting an active contour model to the structure of interest. The fetal biparietal diameter (BPD) and femur length (FL) are then measured automatically. The validation data set contained 167 and 197 B-mode images for BPD and FL measurements, respectively. The images were acquired using 4 different ultrasound scanners, which resulted in varied image quality and gain settings. The mean gestational age (GA) of the fetuses was 19.4 weeks, range 16 to 41 weeks. A measurement success rate of 90% was achieved for both BPD and FL. The correlation coefficients between the manual and automatic measurements were 0.995 (BPD) and 0.967 (FL), mean errors were 0.5 mm (BPD) and -1.7 mm (FL) and error range with 95% confidence interval (CI) were ﹣3.8 - 4.8 mm (BPD) and ﹣11.4 - 8.1 mm (FL). The automatic measurement results were consistent in both high and low gain settings. The intraclass correlation coefficients between manual and automatic measurements were 0.995 (95% CI;0.981 - 0.999) for BPD in high gain, 1.0 (95% CI;0.998 - 1.0) for BPD in low gain, 0.998 (95% CI;0.991 - 0.999) for FL in high gain and 0.999 (95% CI;0.996 - 1.0) for FL in low gain settings. The method was implemented on a prototype, portable ultrasound machine designed to be used in low- and middle-income countries (LMIC). The overall performance of the method supports our hypothesis that automated methods can be used and are beneficial in a clinical setting.展开更多
BACKGROUND: The accurate measurements of various data of the bone diameters of foramen ovale of living person can change the methods of puncturing trigeminal gasserian ganglion via foramen ovale for treating trifacia...BACKGROUND: The accurate measurements of various data of the bone diameters of foramen ovale of living person can change the methods of puncturing trigeminal gasserian ganglion via foramen ovale for treating trifacial neuralgia from the experience of puncture operator only to puncture by taking the objective data of measurement as the evidence, which is good for improving the accuracy of puncturing trigeminal ganglion and reducing side effects. OBJECTIVE : To observe the forms of foramen ovales in healthy adults displayed by volume rendering and multi-planar reconstruction after three-dimensional spiral CT thin-slice scan of skull base, and measure the longitudinal diameter and transverse diameter. DESIGN : A repetitive observation and measurement SETTINGS : Department of Neurosurgery and Department of Medical Imaging, Foshan Hospital of Traditional Chinese Medicine. PARTICIPANTS: Fifty healthy adults (100 sides), who were examined with three-dimensional spiral CT scan, were randomly selected from the Department of Medical Imaging, Foshan Hospital of Traditional Chinese Medicine from January 2005 to January 2006, including 26 males and 24 females, aged 25-68 years with an average of 48 years old. They were all informed and agreed with the examination. METHODS : The subjects were examined with the Philips 16-slice spiral CT-Mx 8000 IDT CT apparatus (Philips Company, Holland), the scanning ranged from 2 cm below the canthomeatal line to the level of suprasellar cistem. The width of collimator was 0.75 mm, pitch was 0.663; tube current was 350 mA, voltage was 120 kV, resolution was 512×512 matrix; slice thickness of reconstruction was 1 mm, and interval was 0.5 mm. After the three-dimensional spiral CT thin-slice scan of skull base, the image post-processing techniques including volume rendering and multi-planar reconstruction were applied to observe the forms of foramen ovales, and measure the size, longitudinal diameter and transverse diameter of the foramen ovales. The figures of the foramen ovales were drawn with mouse along the boundary of bone porous margin and soft tissue. According to the indications, the diameters were measured with computer to observe the forms of foramen ovales. MAIN OUTCOME MEASURES : The longitudinal diameter, transverse diameter and form of foramen ovales were observed. RESULTS: All the 50 healthy adults (100 sides) were involved in the analysis of results. (1) It was observed in the volume rendering images that foramen ovales had four forms of oval shape (77 sides), kidney shape (12 sides), round shape (7 sides), ribbon shape (4 sides). (2) The longitudinal diameters of left and right foramen ovales were (7.67±1.32) and (7.98±1.45) mm, and the transverse diameters were (4.04±0.83), (4.09±1.07) mm; There was no obvious difference between left and right longitudinal diameters (t = 1.63, P = 0.11 ), and left and right transverse diameters were close (t = 0.45, P= 0.65). CONCLUSION : The non-invasive techniques of volume rendering and multi-planar reconstruction after three-dimensional spiral CT thin-slice scan can clearly display the formand size of foramen ovale in healthy adults.展开更多
The present work measured the bulk etch rate (VB?) of solid state nuclear track detector by taking the diameter time measurement of alpha particle in CR-39 detector. The values of the track diameter have been found by...The present work measured the bulk etch rate (VB?) of solid state nuclear track detector by taking the diameter time measurement of alpha particle in CR-39 detector. The values of the track diameter have been found by using TRACK-TEST program from Yu et al. function and Brun et al. function with different energies of alpha particles. The results showed that the time-diameter (t-d) method gave good results of the bulk etch rate (VB?) and these values were (1.705 and 1.72) μm·hr-1. They showed good agreement with the values measured by using the other methods, and it was a simple method because it required getting diameters of the tracks in the detector with the etching time.展开更多
Traumatic brain injury(TBI) is a major contributor of long-term disability and a leading cause of death worldwide. A series of secondary injury cascades can contribute to cell death, tissue loss, and ultimately to the...Traumatic brain injury(TBI) is a major contributor of long-term disability and a leading cause of death worldwide. A series of secondary injury cascades can contribute to cell death, tissue loss, and ultimately to the development of functional impairments. However, there are currently no effective therapeutic interventions that improve brain outcomes following TBI. As a result, a number of experimental TBI models have been developed to recapitulate TBI injury mechanisms and to test the efficacy of potential therapeutics. The pig model has recently come to the forefront as the pig brain is closer in size, structure, and composition to the human brain compared to traditional rodent models, making it an ideal large animal model to study TBI pathophysiology and functional outcomes. This review will focus on the shared characteristics between humans and pigs that make them ideal for modeling TBI and will review the three most common pig TBI models–the diffuse axonal injury, the controlled cortical impact, and the fluid percussion models. It will also review current advances in functional outcome assessment measures and other non-invasive, translational TBI detection and measurement tools like biomarker analysis and magnetic resonance imaging. The use of pigs as TBI models and the continued development and improvement of translational assessment modalities have made significant contributions to unraveling the complex cascade of TBI sequela and provide an important means to study potential clinically relevant therapeutic interventions.展开更多
Under the premise of fully respecting current national standard of table tennis ball,this paper presents an integrated and effective method for testing diameter,roundness and hardness of table tennis ball based on vis...Under the premise of fully respecting current national standard of table tennis ball,this paper presents an integrated and effective method for testing diameter,roundness and hardness of table tennis ball based on vision measurement. Firstly,camera calibration is performed by 40 mm gauge block to capture the images of table tennis ball in static and pressed state in an appropriate lighting condition. Then image binarization and extraction of image contour are carried out. The least square method is used to fit its center. Finally,the diameter,roundness and hardness are calculated. The measurement data are analyzed by using the method presented in this paper for table tennis ball with known parameter data and with unknown parameter data. Experimental results show that this method can improve measurement accuracy and provide a technical basis for the online testing and integration measurement of table tennis ball.展开更多
A diagnostics method was presented that uses emission and scattering techniques to simultaneously determine the distributions of soot particle diameter and number density in hydrocarbon flames. Two manta G-504 C camer...A diagnostics method was presented that uses emission and scattering techniques to simultaneously determine the distributions of soot particle diameter and number density in hydrocarbon flames. Two manta G-504 C cameras were utilized for the scattering measurement, with consideration of the attenuation effect in the flames according to corresponding absorption coefficients. Distributions of soot particle diameter and number density were simultaneously determined using the measured scattering coefficients and absorption coefficients under multiple wavelengths already measured with a SOC701 V hyper-spectral imaging device, according to the Mie scattering theory. A flame was produced using an axisymmetric laminar diffusion flame burner with 194 mL/min ethylene and 284 L/min air, and distributions of particle diameter and number density for the flame were presented. Consequently, the distributions of soot volume fraction were calculated using these two parameters as well, which were in good agreement with the results calculated according to the Rayleigh approximation,demonstrating that the proposed diagnostic method is capable of simultaneous determination of the distributions of soot particle diameter and number density.展开更多
Fragrance pig is a famous miniature local breed in China,which is similar to human on the aspects of physical structure,anatomy,nutrition,metabolism and blood biochemical indicators. The internal organs of Congjiang f...Fragrance pig is a famous miniature local breed in China,which is similar to human on the aspects of physical structure,anatomy,nutrition,metabolism and blood biochemical indicators. The internal organs of Congjiang fragrance pig and Huanjiang fragrance pig with different month ages were weighed. The results showed that the proportion of stomach in body weight in Congjiang fragrance pig was higher than that in Min pig,Harbin white and Landrace,and the proportion of large intestine in body weight in Congjiang fragrance pig was also higher than that in ordinary pigs; the weights of heart,liver and kidney in 8- 10 months old Congjiang fragrance pig were similar to that in Chinese adults. This provided reference data for future in-depth development and utilization of fragrance pig.展开更多
Live measurement growth traits are very important economic traits in pig production and breeding. In this research, quantitative trait loci (QTL) were detected for 11 live estimated growth and carcass traits, includ...Live measurement growth traits are very important economic traits in pig production and breeding. In this research, quantitative trait loci (QTL) were detected for 11 live estimated growth and carcass traits, including birth weight (BWT), average daily gain over testing periods (ADG3), live backfat thickness at last 3-4th lumbar (LBFT3), live loin eye area (LLEA), and so on, in 214 pig resource family population, including 180 F2 individual, by 39 microsatellite marker loci on SSC4, SSC6, SSC7, SSC8, and SSC13. The results indicated that 4 chromosome significant level QTL and one suggestive QTL were detected for ADG3 (at position of 50 cM on SSC8), LBFT3 (at position of 147 cM on SSC4), LLEA (one highly significant at position of 48 cM on SSC7; another significant at position of 125 cM on SSC8) and BWT (suggestive significant at position of 0 cM, at marker sw489 on SSC4). The phenotypic variance of these QTL accounted for 0.95% to 16.91%. Most of them were mentioned in previous reports; except the QTL of LLEA at position of sw1953 on SSC8 which maybe a new QTL.展开更多
An automatic method for measuring the fetal mean abdominal diameter (MAD) or abdominal circumference (AC) with ultrasound is proposed. From a correctly presented abdominal section suitable for MAD or AC measurement, t...An automatic method for measuring the fetal mean abdominal diameter (MAD) or abdominal circumference (AC) with ultrasound is proposed. From a correctly presented abdominal section suitable for MAD or AC measurement, the location of fetal abdomen is detected by image processing. Thereafter, an active contour model is converged along the abdominal boundary for measurement purposes. The validation data set contained 310 images of fetuses with gestational age (GA) from 14 to 41 weeks. The measurement success rate was 88.1%. By manually indicating the location of the abdomen, the success rate was further improved to 95.8% for the failed cases. The correlation between manual and automatic measurements was 0.95 and the intraclass correlation coefficient (ICC) was 0.976 (95% confidence interval (CI);0.969 - 0.981). The average method execution time was 0.3 s. The mean error was lower in young fetuses (0.4%) than in older fetuses (-2.1%). The proposed cross-platform method was implemented on a portable, low-cost ultrasound machine prototype targeted for low- and middle-income countries (LMIC);the results achieved were comparable to those of other state-of-the-art automatic methods.展开更多
Covering the slurry pit has been shown to be one of the best ways to reduce ammonia emissions (NH<sub>3</sub>) during manure management. Yet, few studies have been conducted at farm scale. We studied the f...Covering the slurry pit has been shown to be one of the best ways to reduce ammonia emissions (NH<sub>3</sub>) during manure management. Yet, few studies have been conducted at farm scale. We studied the feasibility of three cover materials (peat, polystyrene balls and synthetic sheet roof) to reduce ammonia (NH<sub>3</sub>) emissions during on-farm storage of pig slurry. The impact on greenhouse gas emissions, methane (CH<sub>4</sub>), nitrous oxide (N<sub>2</sub>O) and carbon dioxide (CO<sub>2</sub>) of covering the slurry pit was also evaluated. Simultaneous field experiments were carried out using two similar pits at a farm with peat and polystyrene ball covers, which allowed direct comparison of the feasibility of the two covers to reduce gas emissions (measured using the dynamic chamber technique). Emissions from the third option (using a synthetic sheet roof) were estimated by measuring the concentrations in the headspace under the cover and the air leakage from the cover with a tracer gas (CO<sub>2</sub>). Results showed that the polystyrene balls cover reduced emissions of NH<sub>3</sub> during storage by up to 80% whatever the season, but increased potential greenhouse gas emissions by 20% in summer. No consistent reduction was achieved with the peat cover even though some individual results seemed to indicate up to 25% reduction in ammonia emissions;moreover, there was a 30% increase in CH<sub>4</sub> and CO<sub>2</sub> emissions during the storage period. The use of a synthetic sheet roof enabled up to 90% reduction in NH<sub>3</sub>, CH<sub>4</sub> and CO<sub>2</sub> emissions whatever the season.展开更多
[Objective] The paper was to determine whether the germplasm resources of Congjiang fragrance pig had changed over the past 30 years. [Method]The growth development and reproductive performance of 100 pigs from six to...[Objective] The paper was to determine whether the germplasm resources of Congjiang fragrance pig had changed over the past 30 years. [Method]The growth development and reproductive performance of 100 pigs from six towns in central fragrance pig producing area and Congjiang fragrance pig stock seed farm were measured,and further compared with the data in Guizhou Livestock and Poultry Breeds 1986. [Result]The growth and development status was basically consistent,and the average litter size was at a downward trend: the first litter decreased by 26. 2%; the second litter decreased by 7. 0%; the third litter decreased by8. 55%. [Conclusion] The study laid the foundation for vigorous promotion of Congjiang fragrance pig in industrial development process,acceleration of breeding pace,gradual updating of farming breeds by farmers and improvement of production efficiency of fragrance pig.展开更多
Forty-seven hybrid progenies from crossbreeding between the Nigerian indigenous pig (NIP) and Large white pigs were used. Body measurements and live weight were recorded weekly from first week of birth to their weanin...Forty-seven hybrid progenies from crossbreeding between the Nigerian indigenous pig (NIP) and Large white pigs were used. Body measurements and live weight were recorded weekly from first week of birth to their weaning date. Body measurements taken were Body Weight (BW), Body Length (BL), Body Height (BH), Heart girth (HG) and Rump circumference (RC) of crossbred progenies. The correlation between the reproductive parameters and growth performance of hybrid pigs were established with good management practice. The mean for weaning weight was 6.72 ± 0.02, birth weight 0.91 ± 0.13, litter size at birth 5.36 ± 1.87, litter size at weaning 5.29 ± 1.97, litter weight at birth 4.56 ± 1.57, total litter weight at weaning 33.91 ± 11.6, average daily weaning weight 0.73 ± 0.12, average litter size at birth 0.93 ± 0.11 and sex ratio 97.78% ± 8.61%. The male and female mean values for weight of animals were 6.96 ± 1.0 and 6.52 ± 0.9 with male heavier in weight and higher in morphometric traits such as body length, heart girth and rump circumference, while the female were high in morphometric traits such as snout length, ear length and body height. The correlation matrix for body weight against linear body measurements in pre-weaned NIP crossbreds indicates that all the parameters could be used to select for body weight. The linear equation generated by regressing body weight on snout length, body height, rump circumference, heart girth and body length could be used by resource poor pig farmers in the estimation of body weight of pre weaned crossbreds pigs if they cannot afford weighing scales.展开更多
基金Supported by the National Natural Science Foundation of China(No.81400428)Self-selected Projects of Shanghai Children’s Hospital(No.2020R124)Shanghai Children’s Hospital Hospital-level Project Clinical Research Cultivation Special Focus Project(No.2021YLYZ03).
文摘AIM:To quantitatively measure ocular morphological parameters of guinea pig with Python technology.METHODS:Thirty-six eyeballs of eighteen 3-weekold guinea pigs were measured with keratometer and photographed to obtain the horizontal,coronal,and sagittal planes respectively.The corresponding photo pixels-actual length ratio was acquired by a proportional scale.The edge coordinates were identified artificially by ginput function.Circle and conic curve fitting were applied to fit the contour of the eyeball in the sagittal,coronal and horizontal view.The curvature,curvature radius,eccentricity,tilt angle,corneal diameter,and binocular separation angle were calculated according to the geometric principles.Next,the eyeballs were removed,canny edge detection was applied to identify the contour of eyeball in vitro.The results were compared between in vivo and in vitro.RESULTS:Regarding the corneal curvature and curvature radius on the horizontal and sagittal planes,no significant differences were observed among results in vivo,in vitro,and the keratometer.The horizontal and vertical binocular separation angles were 130.6°±6.39°and 129.8°±9.58°respectively.For the corneal curvature radius and eccentricity in vivo,significant differences were observed between horizontal and vertical planes.CONCLUSION:The Graphical interface window of Python makes up the deficiency of edge detection,which requires too much definition in Matlab.There are significant differences between guinea pig and human beings,such as exotropic eye position,oblique oval eyeball,and obvious discrepancy of binoculus.This study helps evaluate objectively the ocular morphological parameters of small experimental animals in emmetropization research.
文摘Point-of-care ultrasound has been increasingly used in evaluating shocked patients including the measurement of inferior vena cava(IVC) diameter. Operators should standardize their technique in scanning IVC. Relativechanges are more important than absolute numbers. We advise using the longitudinal view(B mode) to evaluate the gross collapsibility, and the M mode to measure the IVC diameter. Combining the collapsibility and diameter size will increase the value of IVC measurement. This approach has been very useful in the resuscitation of shocked patients, monitoring their fluid demands, and predicting recurrence of shock. Pitfalls in measuring IVC diameter include increased intra-thoracic pressure by mechanical ventilation or increased right atrial pressure by pulmonary embolism or heart failure. The IVC diameter is not useful in cases of increased intra-abdominal pressure(abdominal compartment syndrome) or direct pressure on the IVC. The IVC diameter should be combined with focused echocardiography and correlated with the clinical picture as a whole to be useful.
文摘The optical diffraction is a major means of minute diameter measurements. Since the light intensity of the diffraction fringe, mainly distributed in the central bright stripes, and that will lead to a relatively low SNR for the signal of the senior stripes. The traditional dark stripes extraction algorithm affected greatly by the noise. So this paper presents an algorithm that could effectively eliminate the gross errorcaused by the noise. Than by curve fitting the local signal of the diffraction pattern with the least square principle, the system could achieve a high measurement precision.
基金Supported by Chinese Postdoctoral Science Foundation,Grant 2012T50868
文摘AIM:To measure in vitro diameter of imitational varices using a self-made endoscopic scale and confirm its accuracy and clinical feasibility.METHODS:A catheter was introduced into the endoscopeaccessory channel and attached to a zebra wire guide that was used as a stylet.The wire guide was fixed onto the tip of the catheter by a soft and thin string.By gently advancing the stylet into the catheter,the width of the opening loop at the tip of the endoscope approximated the diameter of the imitational varices.Measurements performed in vitro using this self-made endoscopic ruler were compared to measurements of simulative varices.RESULTS:At the handle,the sleeve moving distance ranged from 5 to 14 mm.There was no obvious proportional relationship between the sleeve movement distance and endoscopic measurement ruler.The results indicated that the gap between the endoscopic measurement and actual measurement of the object size tended to close.The in vitro measurement of the diameter of the simulative varices showed that the two kinds of measuring methods were not significantly different with respect to their accuracy(P=0.8499).CONCLUSION:In vitro experiments confirmed that using a self-designed endoscopic ruler to measure the diameter of simulative varices was objective,accurate and feasible.
基金financially supported by the National Science Foundation of China (grant no. 31400542 31460196)+1 种基金Guangxi Natural Science Foundation (grant 2016GXNSFBA380233)Guangxi special fund project for innovation-driven development (AA 17204087-8)
文摘Forest structure analysis is important for understanding the properties and development of a forest community,and its outcomes can be influenced by how trees are measured in sampled plots.Although there is a general consensus on the height at which tree diameter should be measured[1.3 m:diameter at breast height(DBH)],the minimum measureddiameter(MMD)often varies in different studies.In this study,we assumed that the outcomes of forest structure analysis can be influenced by MMD and,to this end,we applied g(r)function and stand spatial structural parameters(SSSPs)to investigate how different MMDs affect forest spatial structure analysis in two pine-oak mixed forests(30 and 57 years old)in southwest China and one old-growth oak forest(>120years old)from northwest China.Our results showed that 1)MMD was closely related to the distribution patterns of forest trees.Tree distribution patterns at each observational scale(r=0-20 m)tended tobecome random as the MMD increased.The older the community,the earlier this random distribution pattern appeared.2)As the MMD increased,neighboring trees became more regularly distributed around a reference tree.In most cases,however,nearest neighbors of a reference tree were randomly distributed.3)Tree species mingling decreased with increasing diameter,but it decreased slowly in older forests.4)No correlations can be found between individual tree size differentiation and MMD.We recommend that comparisons of spatial structures between communities would be more effective if using a unified MMD criterion.
文摘Based on laser-scanned measuring technology, a met ho d of on-line dynamic non-contact measurement and feedback control of processin g dimension, i.e. the double edges laser-scanned large diameter on-line dynami c measurement and control system is presented, which can be used to measure diam eter in large-scale machine part processing. In this paper, the working princip le, overall structure and microcomputer real-time control and data processing s ystem of the system are discussed in detail, the method of double edges scanned large diameter dimension measurement and control is theoretically analyzed, its possibility has been verified by experiments of lathing large diameters machine parts by a vertical lathe. The system adopts the measuring scheme of double edge s laser-scanned combined with grating displacement measurement. The two edges c haracteristic information of the measured diameter is given by the double edges laser-scanned measuring system, the non-contact measurement of large diameter dimension is realized to combine with the grating displacement measuring systems . The main controller gives out feedback control signal by means of measured res ults, and controls advance and retreat of lathe tool by the servo-control syste m of a vertical lathe to realize on-line dynamic non-contact measurement and c ontrol in processing.
文摘An automatic method able to recognize a presented section through the biparietal plane of the fetal head and a section through the fetal femur in ultrasound images is developed. Once the correct anatomical section for measurement is identified by the machine, the placement of the measurement calipers is automatically determined by fitting an active contour model to the structure of interest. The fetal biparietal diameter (BPD) and femur length (FL) are then measured automatically. The validation data set contained 167 and 197 B-mode images for BPD and FL measurements, respectively. The images were acquired using 4 different ultrasound scanners, which resulted in varied image quality and gain settings. The mean gestational age (GA) of the fetuses was 19.4 weeks, range 16 to 41 weeks. A measurement success rate of 90% was achieved for both BPD and FL. The correlation coefficients between the manual and automatic measurements were 0.995 (BPD) and 0.967 (FL), mean errors were 0.5 mm (BPD) and -1.7 mm (FL) and error range with 95% confidence interval (CI) were ﹣3.8 - 4.8 mm (BPD) and ﹣11.4 - 8.1 mm (FL). The automatic measurement results were consistent in both high and low gain settings. The intraclass correlation coefficients between manual and automatic measurements were 0.995 (95% CI;0.981 - 0.999) for BPD in high gain, 1.0 (95% CI;0.998 - 1.0) for BPD in low gain, 0.998 (95% CI;0.991 - 0.999) for FL in high gain and 0.999 (95% CI;0.996 - 1.0) for FL in low gain settings. The method was implemented on a prototype, portable ultrasound machine designed to be used in low- and middle-income countries (LMIC). The overall performance of the method supports our hypothesis that automated methods can be used and are beneficial in a clinical setting.
基金a grant fromTackle Key Problems in Sci-ence and Technology of FoshanCity, No. 200505075
文摘BACKGROUND: The accurate measurements of various data of the bone diameters of foramen ovale of living person can change the methods of puncturing trigeminal gasserian ganglion via foramen ovale for treating trifacial neuralgia from the experience of puncture operator only to puncture by taking the objective data of measurement as the evidence, which is good for improving the accuracy of puncturing trigeminal ganglion and reducing side effects. OBJECTIVE : To observe the forms of foramen ovales in healthy adults displayed by volume rendering and multi-planar reconstruction after three-dimensional spiral CT thin-slice scan of skull base, and measure the longitudinal diameter and transverse diameter. DESIGN : A repetitive observation and measurement SETTINGS : Department of Neurosurgery and Department of Medical Imaging, Foshan Hospital of Traditional Chinese Medicine. PARTICIPANTS: Fifty healthy adults (100 sides), who were examined with three-dimensional spiral CT scan, were randomly selected from the Department of Medical Imaging, Foshan Hospital of Traditional Chinese Medicine from January 2005 to January 2006, including 26 males and 24 females, aged 25-68 years with an average of 48 years old. They were all informed and agreed with the examination. METHODS : The subjects were examined with the Philips 16-slice spiral CT-Mx 8000 IDT CT apparatus (Philips Company, Holland), the scanning ranged from 2 cm below the canthomeatal line to the level of suprasellar cistem. The width of collimator was 0.75 mm, pitch was 0.663; tube current was 350 mA, voltage was 120 kV, resolution was 512×512 matrix; slice thickness of reconstruction was 1 mm, and interval was 0.5 mm. After the three-dimensional spiral CT thin-slice scan of skull base, the image post-processing techniques including volume rendering and multi-planar reconstruction were applied to observe the forms of foramen ovales, and measure the size, longitudinal diameter and transverse diameter of the foramen ovales. The figures of the foramen ovales were drawn with mouse along the boundary of bone porous margin and soft tissue. According to the indications, the diameters were measured with computer to observe the forms of foramen ovales. MAIN OUTCOME MEASURES : The longitudinal diameter, transverse diameter and form of foramen ovales were observed. RESULTS: All the 50 healthy adults (100 sides) were involved in the analysis of results. (1) It was observed in the volume rendering images that foramen ovales had four forms of oval shape (77 sides), kidney shape (12 sides), round shape (7 sides), ribbon shape (4 sides). (2) The longitudinal diameters of left and right foramen ovales were (7.67±1.32) and (7.98±1.45) mm, and the transverse diameters were (4.04±0.83), (4.09±1.07) mm; There was no obvious difference between left and right longitudinal diameters (t = 1.63, P = 0.11 ), and left and right transverse diameters were close (t = 0.45, P= 0.65). CONCLUSION : The non-invasive techniques of volume rendering and multi-planar reconstruction after three-dimensional spiral CT thin-slice scan can clearly display the formand size of foramen ovale in healthy adults.
文摘The present work measured the bulk etch rate (VB?) of solid state nuclear track detector by taking the diameter time measurement of alpha particle in CR-39 detector. The values of the track diameter have been found by using TRACK-TEST program from Yu et al. function and Brun et al. function with different energies of alpha particles. The results showed that the time-diameter (t-d) method gave good results of the bulk etch rate (VB?) and these values were (1.705 and 1.72) μm·hr-1. They showed good agreement with the values measured by using the other methods, and it was a simple method because it required getting diameters of the tracks in the detector with the etching time.
文摘Traumatic brain injury(TBI) is a major contributor of long-term disability and a leading cause of death worldwide. A series of secondary injury cascades can contribute to cell death, tissue loss, and ultimately to the development of functional impairments. However, there are currently no effective therapeutic interventions that improve brain outcomes following TBI. As a result, a number of experimental TBI models have been developed to recapitulate TBI injury mechanisms and to test the efficacy of potential therapeutics. The pig model has recently come to the forefront as the pig brain is closer in size, structure, and composition to the human brain compared to traditional rodent models, making it an ideal large animal model to study TBI pathophysiology and functional outcomes. This review will focus on the shared characteristics between humans and pigs that make them ideal for modeling TBI and will review the three most common pig TBI models–the diffuse axonal injury, the controlled cortical impact, and the fluid percussion models. It will also review current advances in functional outcome assessment measures and other non-invasive, translational TBI detection and measurement tools like biomarker analysis and magnetic resonance imaging. The use of pigs as TBI models and the continued development and improvement of translational assessment modalities have made significant contributions to unraveling the complex cascade of TBI sequela and provide an important means to study potential clinically relevant therapeutic interventions.
文摘Under the premise of fully respecting current national standard of table tennis ball,this paper presents an integrated and effective method for testing diameter,roundness and hardness of table tennis ball based on vision measurement. Firstly,camera calibration is performed by 40 mm gauge block to capture the images of table tennis ball in static and pressed state in an appropriate lighting condition. Then image binarization and extraction of image contour are carried out. The least square method is used to fit its center. Finally,the diameter,roundness and hardness are calculated. The measurement data are analyzed by using the method presented in this paper for table tennis ball with known parameter data and with unknown parameter data. Experimental results show that this method can improve measurement accuracy and provide a technical basis for the online testing and integration measurement of table tennis ball.
基金Project supported by the National Key Research and Development Program of China(Grant No.2017YFB0601900)the National Natural Science Foundation of China(Grant Nos.51827808,51821004,and 51406095)+1 种基金the Fundamental Research Funds for the Central Universities,China(Grant Nos.2018ZD03 and2017ZZD005)Science and Technology Partnership Program,Ministry of Science and Technology of China(Grant No.KY201401003)
文摘A diagnostics method was presented that uses emission and scattering techniques to simultaneously determine the distributions of soot particle diameter and number density in hydrocarbon flames. Two manta G-504 C cameras were utilized for the scattering measurement, with consideration of the attenuation effect in the flames according to corresponding absorption coefficients. Distributions of soot particle diameter and number density were simultaneously determined using the measured scattering coefficients and absorption coefficients under multiple wavelengths already measured with a SOC701 V hyper-spectral imaging device, according to the Mie scattering theory. A flame was produced using an axisymmetric laminar diffusion flame burner with 194 mL/min ethylene and 284 L/min air, and distributions of particle diameter and number density for the flame were presented. Consequently, the distributions of soot volume fraction were calculated using these two parameters as well, which were in good agreement with the results calculated according to the Rayleigh approximation,demonstrating that the proposed diagnostic method is capable of simultaneous determination of the distributions of soot particle diameter and number density.
文摘Fragrance pig is a famous miniature local breed in China,which is similar to human on the aspects of physical structure,anatomy,nutrition,metabolism and blood biochemical indicators. The internal organs of Congjiang fragrance pig and Huanjiang fragrance pig with different month ages were weighed. The results showed that the proportion of stomach in body weight in Congjiang fragrance pig was higher than that in Min pig,Harbin white and Landrace,and the proportion of large intestine in body weight in Congjiang fragrance pig was also higher than that in ordinary pigs; the weights of heart,liver and kidney in 8- 10 months old Congjiang fragrance pig were similar to that in Chinese adults. This provided reference data for future in-depth development and utilization of fragrance pig.
基金the National 973 Project of China (G2000016105) National Natural Science Foundation of China (30500358).
文摘Live measurement growth traits are very important economic traits in pig production and breeding. In this research, quantitative trait loci (QTL) were detected for 11 live estimated growth and carcass traits, including birth weight (BWT), average daily gain over testing periods (ADG3), live backfat thickness at last 3-4th lumbar (LBFT3), live loin eye area (LLEA), and so on, in 214 pig resource family population, including 180 F2 individual, by 39 microsatellite marker loci on SSC4, SSC6, SSC7, SSC8, and SSC13. The results indicated that 4 chromosome significant level QTL and one suggestive QTL were detected for ADG3 (at position of 50 cM on SSC8), LBFT3 (at position of 147 cM on SSC4), LLEA (one highly significant at position of 48 cM on SSC7; another significant at position of 125 cM on SSC8) and BWT (suggestive significant at position of 0 cM, at marker sw489 on SSC4). The phenotypic variance of these QTL accounted for 0.95% to 16.91%. Most of them were mentioned in previous reports; except the QTL of LLEA at position of sw1953 on SSC8 which maybe a new QTL.
文摘An automatic method for measuring the fetal mean abdominal diameter (MAD) or abdominal circumference (AC) with ultrasound is proposed. From a correctly presented abdominal section suitable for MAD or AC measurement, the location of fetal abdomen is detected by image processing. Thereafter, an active contour model is converged along the abdominal boundary for measurement purposes. The validation data set contained 310 images of fetuses with gestational age (GA) from 14 to 41 weeks. The measurement success rate was 88.1%. By manually indicating the location of the abdomen, the success rate was further improved to 95.8% for the failed cases. The correlation between manual and automatic measurements was 0.95 and the intraclass correlation coefficient (ICC) was 0.976 (95% confidence interval (CI);0.969 - 0.981). The average method execution time was 0.3 s. The mean error was lower in young fetuses (0.4%) than in older fetuses (-2.1%). The proposed cross-platform method was implemented on a portable, low-cost ultrasound machine prototype targeted for low- and middle-income countries (LMIC);the results achieved were comparable to those of other state-of-the-art automatic methods.
文摘Covering the slurry pit has been shown to be one of the best ways to reduce ammonia emissions (NH<sub>3</sub>) during manure management. Yet, few studies have been conducted at farm scale. We studied the feasibility of three cover materials (peat, polystyrene balls and synthetic sheet roof) to reduce ammonia (NH<sub>3</sub>) emissions during on-farm storage of pig slurry. The impact on greenhouse gas emissions, methane (CH<sub>4</sub>), nitrous oxide (N<sub>2</sub>O) and carbon dioxide (CO<sub>2</sub>) of covering the slurry pit was also evaluated. Simultaneous field experiments were carried out using two similar pits at a farm with peat and polystyrene ball covers, which allowed direct comparison of the feasibility of the two covers to reduce gas emissions (measured using the dynamic chamber technique). Emissions from the third option (using a synthetic sheet roof) were estimated by measuring the concentrations in the headspace under the cover and the air leakage from the cover with a tracer gas (CO<sub>2</sub>). Results showed that the polystyrene balls cover reduced emissions of NH<sub>3</sub> during storage by up to 80% whatever the season, but increased potential greenhouse gas emissions by 20% in summer. No consistent reduction was achieved with the peat cover even though some individual results seemed to indicate up to 25% reduction in ammonia emissions;moreover, there was a 30% increase in CH<sub>4</sub> and CO<sub>2</sub> emissions during the storage period. The use of a synthetic sheet roof enabled up to 90% reduction in NH<sub>3</sub>, CH<sub>4</sub> and CO<sub>2</sub> emissions whatever the season.
文摘[Objective] The paper was to determine whether the germplasm resources of Congjiang fragrance pig had changed over the past 30 years. [Method]The growth development and reproductive performance of 100 pigs from six towns in central fragrance pig producing area and Congjiang fragrance pig stock seed farm were measured,and further compared with the data in Guizhou Livestock and Poultry Breeds 1986. [Result]The growth and development status was basically consistent,and the average litter size was at a downward trend: the first litter decreased by 26. 2%; the second litter decreased by 7. 0%; the third litter decreased by8. 55%. [Conclusion] The study laid the foundation for vigorous promotion of Congjiang fragrance pig in industrial development process,acceleration of breeding pace,gradual updating of farming breeds by farmers and improvement of production efficiency of fragrance pig.
文摘Forty-seven hybrid progenies from crossbreeding between the Nigerian indigenous pig (NIP) and Large white pigs were used. Body measurements and live weight were recorded weekly from first week of birth to their weaning date. Body measurements taken were Body Weight (BW), Body Length (BL), Body Height (BH), Heart girth (HG) and Rump circumference (RC) of crossbred progenies. The correlation between the reproductive parameters and growth performance of hybrid pigs were established with good management practice. The mean for weaning weight was 6.72 ± 0.02, birth weight 0.91 ± 0.13, litter size at birth 5.36 ± 1.87, litter size at weaning 5.29 ± 1.97, litter weight at birth 4.56 ± 1.57, total litter weight at weaning 33.91 ± 11.6, average daily weaning weight 0.73 ± 0.12, average litter size at birth 0.93 ± 0.11 and sex ratio 97.78% ± 8.61%. The male and female mean values for weight of animals were 6.96 ± 1.0 and 6.52 ± 0.9 with male heavier in weight and higher in morphometric traits such as body length, heart girth and rump circumference, while the female were high in morphometric traits such as snout length, ear length and body height. The correlation matrix for body weight against linear body measurements in pre-weaned NIP crossbreds indicates that all the parameters could be used to select for body weight. The linear equation generated by regressing body weight on snout length, body height, rump circumference, heart girth and body length could be used by resource poor pig farmers in the estimation of body weight of pre weaned crossbreds pigs if they cannot afford weighing scales.