[Analysis of risk factors for post-polypectomy bleeding and polyp recurrence after colonoscopic polypectomy in children]

Objective: To explore the incidence and the risk factors of post-polypectomy bleeding and polyp recurrence after colonoscopic high-frequency electrocoagulation snare polypectomy. Methods: Clinical data of 1 826 children who underwent colonoscopic high-frequency electrocoagulation snare polypectomy in the Children's Hospital, Zhejiang University School of Medicine from January 2009 to December 2020 was retrospectively analyzed. Demographic characteristics, endoscopic manifestations, pathological features, diagnosis, occurrence of post-polypectomy bleeding and polyp recurrence were collected. The associated risk factors were analyzed by Logistic regression. Results: A total of 1 826 children (1 191 males and 635 females) with 1 967 polypectomies were included. The age was 4.6 (3.2, 6.4) years at initial diagnosis. According to the initial colonoscopy, 1 611 children (88.2%) had solitary polyps, 1 707 children (93.5%) had pedicled polyps, 1 151 children (63.0%) had polyps involving the rectum, and 1 757 children (96.2%) had hamartomatous polyps. Polyposis syndromes were diagnosed in 73 children (4.0%). The post-polypectomy bleeding occurrence was 3.8% (75/1 967). Polyps recurred in 88 children (4.8%). Girls (OR=2.01, 95%CI 1.26-3.23) and sessile polyps (OR=2.28, 95%CI 1.15-4.49) were risk factors for post-polypectomy bleeding (both P<0.05). Multiple polyps (OR=17.49, 95%CI 9.82-31.18), right-colon involvement (OR=3.44, 95%CI 1.89-6.26) and non-hamartoma (OR=2.51, 95%CI 1.04-6.07) were risk factors for polyp recurrence (all P<0.05). Conclusions: Colonoscopic high-frequency electrocoagulation snare polypectomy has low incidence of post-polypectomy bleeding and polyp recurrence. Female patients and sessile polyps have higher risk for post-polypectomy bleeding. Multiple polyps, right-colon involvement and non-hamartoma polyps increase the risk for polyp recurrence.

Estimation of Cavities beneath Plate Structures Using a Microphone: Laboratory Model Tests

The objective of this study is to detect a cavity and estimate its size using sound waves in a laboratory model chamber filled with dry sand. One side of the chamber is covered with an acrylic plate, and a cavity is placed between the plate and sand. Sound waves are generated by impacting the plate with an instrumented hammer, and are measured using a microphone. The measured sound waves are analyzed with four comprehensive analyses including the measured area under the rectified signal envelope (MARSE) energy, flexibility, peak magnitude of wavelet transform, and frequency corresponding to the peak magnitude. The test results show that the accuracy of cavity detection using the MARSE energy is higher for thicker plates, whereas that using flexibility is higher for thinner plates. The accuracies of cavity detection using the peak magnitude of wavelet transform, and frequency corresponding to the peak magnitude are consistently high regardless of the plate thickness. Moreover, the cavity size may be under- or overestimated depending on the plate thickness and the selected analysis method. The average of the cavity sizes estimated by these methods, however, is slightly larger than the actual cavity size regardless of the plate thickness. This study demonstrates that microphones may be effectively used for the identification of a cavity and the estimation of its size.

Piezoelectric Ring Bender for Characterization of Shear Waves in Compacted Sandy Soils

Shear wave velocity and small-strain shear modulus are widely used as the mechanical properties of soil. The objective of this study is to develop a new shear wave monitoring system using a pair of piezoelectric ring benders (RBs) and to evaluate the suitability of RB in compacted soils compared with the bender element and ultrasonic transducer. The RB is a multilayered piezoelectric actuator, which can generate shear waves without disturbing soils. For five compacted soil specimens, the shear waves are monitored by using three different piezoelectric transducers. Results of time-domain response show that the output signals measured from the RB vary according to the water content of the specimen and the frequency of the input signal. Except at the water content of 9.3%, the difference in the resonant frequencies between the three transducers is not significant. The shear wave velocities for the RB are slightly greater than those for the other transducers. For the RB, the exponential relationship between the shear wave velocity and dry unit weight is better established compared with that of the other transducers. The newly proposed piezoelectric transducer RB may be useful for the evaluation of the shear wave velocity and small-strain shear modulus of compacted soils.

Horizontally Elongated Time Domain Reflectometry System for Evaluation of Soil Moisture Distribution

The objective of this study was to develop a horizontally elongated time domain reflectometry (HETDR) system to evaluate the water content in nonuniformly wetted soils. The HETDR probe consists of three rods of stainless steel and a cuboid head: A center electrode and two outer electrodes are connected to the inner and outer conductors of a coaxial cable, respectively. An acrylic container divided into several segments was used to prepare nonuniformly wetted soils with different water contents for a series of model tests. The HETDR probe was placed horizontally at the middle height of each soil specimen, while a conventional time domain reflectometry (TDR) probe was applied vertically on the surface of the specimen. The experimental results show that as the soil water content (SWC) at a segment increases, the average amplitude decreases and the duration increases. The estimated SWC increases with the measured SWC, and especially, the difference between actual segment length and the segment length estimated from the HETDR probes is significant under dry conditions. This study demonstrates that HETDR may be a promising field-testing method for evaluating the average water content in nonuniformly wetted soils.

Strength Characteristics of Sand-Silt Mixtures Subjected to Cyclic Freezing-Thawing-Repetitive Loading

Daily freezing-thawing-repetitive loading is a critical factor affecting soil stability. This study assesses the strength of sand–silt mixtures with various silt fractions (SFs) subjected to cyclic freezing-thawing-repetitive loading. Specimens with SF of 0–100% were prepared with a fixed relative density of 60%. The number of repetitive loadings (N) was 1, 100, and 1000 for each specimen with different SFs. After three cycles of freezing-thawing-repetitive loading, the specimens were frozen at −5 °C for the uniaxial compression test. Test results show that the change in relative density (∆D_r) increases with the increase in SF up to 30% and decreases as SF increases beyond 30% owing to the change in the void ratio. The volumetric unfrozen water content (θ_u) increases with the increase in both SF and N owing to the effect of the physicochemical characteristics of soils on small voids. Unconfined compressive strength of sand-dominant mixtures (SF ≤ 30%) is reinforced by ∆D_r. By contrast, for silt-dominant mixtures (SF > 30%), the unconfined compressive strength decreases with the increase in θ_u and N due to lubricant role and sands dispersion. Thus, the effects of SF and N should be considered for sand–silt mixtures that have a probability to undergo cyclic freezing-thawing-repetitive loading.

Dynamic Cone Penetrometer Incorporated with Time Domain Reflectometry (TDR) Sensors for the Evaluation of Water Contents in Sandy Soils

Ground moisture content and strength properties are the most important factors for a proper assessment of ground stability. This study developed a dynamic cone penetrometer incorporated with time domain reflectometry (TDR) sensors (TDCP). The TDCP is composed of an anvil, a driving rod, and a TDCP probe. Three wave guides and a K-type thermocouple are installed on the TDCP probe. For utilization of TDCP, relationships between relative permittivities measured by TDCP and those measured by standard TDR probe, temperature, and volumetric water content of the soils were investigated. In addition, the relationship between penetration indices by TDCP (TPI) and by standard dynamic cone penetrometer was established. In the field application test, relative permittivity, ground temperature, and TPI were measured along the depth. Moreover, gravimetric water contents were also measured for comparison. The experimental results showed that volumetric water contents compensated by ground temperature showed good agreement with the volumetric water contents estimated from the gravimetric water contents of the soil samples and TPI. This study suggests that the TDCP may be effectively used for the evaluation moisture contents and for the strength characterization of the subsurface.

[Endoscopic management of ingested foreign bodies in the upper gastrointestinal tract in childhood: a retrospective study of 1 334 cases]

Objective: To explore the clinical features and complications of foreign bodies in the upper gastrointestinal tract in children and to investigate the effectiveness of endoscopic management. Methods: Data of patients with foreign bodies in upper gastrointestinal tract were collected retrospectively at Endoscopy Center, the Children's Hospital, Zhejiang University School of Medicine, from January 2011 to December 2016. Clinical characteristics, the types of foreign bodies, the location and duration of foreign body impaction were summarized. The risk factors of complications and endoscopic removal failure were analyzed by using Logistic regression analysis. Results: A total of 1 334 patients (825 males and 509 females) were enrolled. The median age was 2.5 years, with a range from 0.25 to 15 years and peak age 1-3 years. Twenty patients had esophageal diseases. The most common foreign body ingested was coin (n=964, 72.3%). Foreign bodies were most commonly located in the esophagus (n=1 002, 75.1%), especially in the upper esophagus (n=857, 85.5%). The duration of foreign body impaction ranged from 3 hours to 5 years. Among 1 334 patients, 252 patients (18.9%) developed complications, including ulcers (n=101, 40.0%) and perforations(n=13, 5.2%). The success rate of endoscopic removal was 96.6% (n=1 288). By Logistic regression analysis, sharp foreign body ingestion (OR=6.893, 95%CI: 4.421-10.746) , esophageal impaction (OR=5.253, 95%CI:3.352-8.233) and foreign body impaction longer than 24 hours (OR=4.336, 95%CI:3.091-6.082) were risk factors of complications. Sharp foreign body ingestion was the risk factor of endoscopic failure (OR=5.372, 95%CI:2.773-10.406) . Conclusions: Coin is the most common foreign body in upper gastrointestinal tract. Sharp foreign bodies impacted in the esophagus over 24 hours increase the risk of complications. Endoscopic removal of foreign bodies from the upper gastrointestinal tract in children has a high success rate. Sharp foreign body ingestion increases the risk of failure in endoscopic removing.

[Effect of enteral nutrition on accidental upper gastrointestinal injury in children]

Objective: To evaluate the effectiveness of enteral nutrition in children with accidental upper gastrointestinal injury. Methods: The medical records of 128 patients with mechanical or chemical gastrointestinal mucosal injury, who were hospitalized in Department of Gastroenterology, Children's Hospital of Zhejiang University School of Medicine from January 1, 2011 to December 30, 2017, were collected. All cases were treated with enteral nutrition. The clinical features and etiologies were retrospectively analyzed. Weight-for-age Z score and lab findings including white blood cells, C-reactive protein, neutrophils, albumin, prealbumin, urea nitrogen and hemoglobin before and after treatment were extracted. The clinical characteristics, the duration of enteral nutrition and gastrointestinal mucosal healing between different etiologies were further analyzed. Normal distribution variables and categorized variables were compared with t test and χ(2) test respectively, and abnormal distribution data was compared with Wilcoxon test. Results: Among all the cases, 77 were males and 51 were females. The average age was (29±22) months. The mean duration of hospitalization and enteral nutrition were (11±7)d and (27±20)d respectively. Vomiting was the most common clinical presentation (72 cases, 56.3%). In 79 cases the problems were caused by mechanical injury, among which coins were most commonly seen. The rest 49 cases were caused by chemical injury. However, the duration of hospitalization ((13±8) d vs. (10±6)d, t=-3.089, P=0.002) and enteral nutrition ((39±22) vs. (19±14) d, t=-5.365, P=0.000) were longer in children with chemical injury than those with mechanical injury. A total of 112 cases got complete blood count and C-reactive protein both before and after enteral nutrition. Inflammatory markers, including leukocytes ((7.7±2.7) ×10(9)/L vs. (13.7±5.0) ×10(9)/L, t=12.244, P <0.05), neutrophils ((3.4±1.9)×10(9)/L vs. (9.4±4.6) ×10(9)/L, t=13.655, P<0.05), and C-reactive proteins (5.0(3.0,7.8) vs. 13.5(6.0,40.5) mg/L, Z=7.776, P <0.05) were significantly decreased. The nutritional markers, including the weight-for-age z score (-0.1 ± 1.0 vs. 0.0 ± 1.0, t=-2.622, P=0.010) and the prealbumin (0.1 ± 0.1 vs. 0.2 ± 0.0 g/L, t=-3.671, P=0.001) were significantly increased. Fifty-five (82.1%) children in mechanical injury group recovered in 4 weeks, while 27 (79.4%) children in chemical injury group recovered in 7 weeks. Conclusion: Enteral nutrition can provide adequate nutritional requirements for children with upper gastrointestinal injury, and may help to decrease imflammation and improve mucosal healing.

[X-linked inhibitor of apoptosis deficiency manifested as Crohn's disease: a case report and literature review]

Objective: To analyze the clinical characteristics of X-linked inhibitor of apoptosis (XIAP) deficient patients with clinical manifestation of Crohn's disease. Methods: Clinical manifestations, laboratory investigations, genetic testing and therapeutic interventions of one case of XIAP deficiency who was admitted to Department of Gastroenterology in Children's Hospital, Zhejiang University School of Medicine in May 2016 were summarized. PubMed and Chinese database for articles published from January 2016 to June 2017 were searched using the key words of'Crohn's disease'and'XIAP', and the relevant literature was reviewed. Results: The case we reported was a 6-year-1-month-old boy with recurrent bloody stool for 2 months, and abdominal pain with fever for 2 weeks. The patient had a past history of hemophagocytic lymphohistiocytosis (HLH) and epilepsy in the past one year. Complete blood cell count showed mild anemia (Hb108 g/L). The patient had an elevated high-sensitivity C reactive protein (86 mg/L) and erythrocyte sedimentation rate (46 mm/1h) . White blood cells, pus cells and red blood cells were found on routine stool examination. Biochemical panel showed hypoalbuminemia (25.2 g/L) , elevated transaminase (alanine aminotransferase 175 U/L, aspartate transaminase 229 U/L) , hypertriglyceridemia (4.41 mmol/L) , and hyperferritinemia (>1 650.0 μg/L) . Magnetic resonance enterography revealed the intestinal wall thickening and increased enhancement in parts of illeum and colon. Capsule endoscopy revealed multiple ulcers in jejunum. Colonoscopy showed multiple ulcers in colon and the pathological examination revealed chronic inflammation in mucosa of terminal ileum and colon, which was combined with partial necrosis and ulceration. Some phagocytes were seen in bone marrow smears. The patient was given multiple diagnoses, including hemophagocytic lymphohistiocytosis, Crohn's disease, sepsis, epilepsy, severe malnutrition, and hypoproteinemia. The pediatric Crohn's disease activity index (PCDAI) was 37.5. Genetic testing identified a hemizygotic mutation of c.910G>T chrX:123022501 p.G304X in XIAP. The parents had no such mutation. The patient showed response to infliximab with oral intake of mercaptopurine and corticosteroids, and had remission with PCDAI of 0. There were 9 relevant articles (Chinese 0 English 9), which showed 33.3% XIAP deficient patients manifested with inflammatory bowel disease(IBD), who might have other manifestations such as hemophagocytic lymphohistiocytosis or splenomegaly simultaneously or sequentially. Those patients showed poor response to monotherapy. Conclusion: XIAP deficient patients have various clinical manifestations. Genetic testing is important to those male pediatric IBD patients who have the complicated symptoms or little response to standard therapy.

[Effect of occupational exposure on job burnout in nurses]

Objective: To investigate the effect of occupational exposure on job burnout in nurses, and to analyze the mediating effect of negative emotion between occupational exposure and job burnout and the regulatory effect of supervisor support on occupational exposure and negative emotion. Methods: From September to December, 2015, simple random sampling was used to select 543 nurses from six tertiary hospitals in Zhejiang Province, China. The questionnaires consisted of occupational exposure risk questionnaire, negative emotion questionnaire, supervisor support questionnaire, and job burnout questionnaire. Results: The total score of occupational exposure risk in nurses was 11.43±7.19; the score of emotional exhaustion was 3.19±1.24, the score of low sense of personal accomplishment was 3.02±1.21, and the score of sense of working indifference was 2.24±1.06. There were significant differences in occupational exposure score between nurses with different sexes (t=2.61, P<0.01) and working years (F=4.49, P<0.01) . There were significant differences in the scores of emotional exhaustion and low sense of personal accomplishment in nurses with different sexes (t=5.25, P<0.001) and working years (t=-3.48, P<0.01) . Occupational exposure had positive effects on negative emotion (β=0.41, P<0.05) , emotional exhaustion (β=0.47, P<0.05) , sense of working indifference (β=0.42, P<0.05) , and low sense of personal accomplishment (β=0.17, P<0.05) . Negative emotion had a partial mediating effect between occupational exposure and emotional exhaustion (total effect size 30.5%, P<0.05) and between occupational exposure and sense of working indifference (total effect size 37.1%, P<0.05) . Negative emotion had a complete mediating effect between occupational exposure and low sense of personal accomplishment (β=0.08, P>0.05) . Supervisor support negatively regulate the effects of occupational exposure and negative emotion (F=21.73, P<0.001) . Conclusion: In nurses, occupational exposure has a direct positive effect on job burnout and indirectly influences job burnout via negative emotion. Supervisor support can reduce the negative impact of occupational exposure on negative emotion.

Role of proximal gastric acid reflux in causation of respiratory symptoms in children with gastroesophageal reflux

OBJECTIVES

The association of gastroesophageal reflux (GER) and respiratory disorders is well known but the mechanism is still unclear. This study aims to evaluate the presence and severity of proximal gastric acid reflux in children having GER with or without respiratory symptoms.

METHODS

24 hour esophageal pH monitoring with a dual pH probe placed in the proximal and distal esophagus was performed in 23 and 31 children having GER with or without respiratory symptoms, respectively.

RESULTS

No significant difference in the parameters of pH monitoring in either proximal or distal esophagus was observed between GER patients with or without respiratory symptoms. The proportion of patients having proximal GER among those with respiratory symptoms was not significantly different from those without respiratory symptoms (P > 0.05).

CONCLUSION

Proximal esophageal acid reflux does not seem to play a role in the development of persistent respiratory symptoms in children with GER. Distal esophageal acid reflux is the predominant form of reflux in children with GER regardless of the occurrence of respiratory symptoms.

Association of the R485K polymorphism of the factor V gene with poor response to activated protein C and increased risk of coronary artery disease in the Chinese population

Inherited predisposition to thrombosis contributes to the initiation and progression of coronary artery disease (CAD). The present study was designed to explore the relationship between genetic variation of coagulation factor V and occurrence of CAD. A total of 141 unrelated patients with CAD and 175 healthy controls were analyzed by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) for variation detection in all 25 exons of the factor V gene. Among the study subjects, 55 CAD patients and 73 controls were evaluated at random for response to activated protein C (APC) by Coatest APC resistance test. Polymorphisms in exon 4, 10, 13 and 16 of factor V gene were documented [642G-->T(S156), 1628--> A(R485K), 4070A-->G(H1299R) and 5380G A(V1736M), respectively]. The study also identified a novel polymorphism 327A G in exon 2 which did not alter the amino acid residue. Leiden mutation (R506Q) was not detected in any of our 316 subjects. Among the five polymorphisms, the allele frequency of 1628G--> A was significantly different between the CAD patients and the controls (0.36 vs. 0.21, p < 0.05). Subjects homozygous or heterozygous for the A allele of 1628G-->A polymorphism had lower normalized APC ratios than those with the GG genotype in the CAD group (1.16+/-0.13 and 1.18+/-0.23 vs. 1.36+/-0.33, p <0.05) and in the controls, indicating that A(1628) allele was associated with a poor response to APC. We conclude that the 1628G-->A (R485K) polymorphism of factor V is associated with a poor response to APC and increased risk for CAD.

Piezoelectric ceramic disks with thickness-graded material properties

A system of two-dimensional, first-order equations for electroded piezoelectric crystal plates with general symmetry and thickness-graded material properties recently was deduced from the three-dimensional equations of linear piezoelectricity. These equations are simplified for the two limiting cases of thickness-graded piezoelectric properties, i.e., the homogeneous plate and bimorph of piezoelectric ceramics. Closed-form solutions are obtained from these reduced equations for the flexural and thickness-shear vibrations and static response of bimorph disks as well as for the extensional and thickness-stretch vibrations of homogeneous disks. Frequency spectra and modes are computed and examined. Resonance frequencies for both homogeneous and bimorph disks of PZT-857 are computed and measured. The comparison of the results shows that the agreement is close.

Governing equations for a piezoelectric plate with graded properties across the thickness

Two-dimensional first-order governing equations for electroded piezoelectric crystal plates with general symmetry and thickness-graded material properties are deduced from the three-dimensional equations of linear piezoelectricity by Mindlin's general procedure of series expansion. Mechanical displacements and thickness-graded material properties, i.e., the elastic stiffnesses, piezoelectric coefficients, dielectric permittivities, and mass density, are expanded in powers of the thickness coordinate, while electric potential is expanded in a special series in order to accommodate the specified electric potentials at electroded faces of the plate. The effects of graded material properties on the piezoelectrically induced stresses or deformations by the applied surface potentials are clearly exhibited in these newly derived equations which reduce to Mindlin's first-order equations of elastic anisotropic plates when the material properties are homogeneous. Closed form solutions are obtained from the three-dimensional equations of piezoelectricity and from the present two-dimensional equations for both homogeneous plates and bimorphs of piezoelectric ceramics. Dispersion curves for homogeneous plates and bimorphs and resonance frequencies for bimorph strips with finite width are computed from the solutions of three-dimensional and two-dimensional equations. Comparison of the results shows that predictions from the two-dimensional equations are very close to those from the three-dimensional equations.

Identification of a novel missense mutation in the cardiac beta-myosin heavy chain gene in a Chinese patient with sporadic hypertrophic cardiomyopathy

The exons 13, 16, 21 and 23 of cardiac beta-myosin heavy chain (MHC) gene from 32 Chinese patients with hypertrophic cardiomyopathy were analyzed by the polymerase chain reaction and the DNA single strand conformation polymorphism (PCR-SSCP) procedure. The results showed an altered SSCP in exon 13 of one patient. Sequencing analysis revealed that the patient had a G to T transversion in codon 383, resulting in the substitution of Lys by Asn. The missense mutation was also confirmed by Southern blot hybridization with an allele-specific oligonucleotide probe. Because it was found at a residue highly conserved through evolution, this mutation is likely to be the cause of hypertrophic cardiomyopathy in the patient. Because her parents and child were neither clinically nor genetically affected, it was concluded that the mutation in this patient arose de novo and was not passed to her child. This is the first report of a mutant cardiac beta-MHC gene in the Chinese population. Also, it is a novel missense mutation of the cardiac beta-MHC gene.

The turbulent noise ratio: an estimation of noise power of the breathy voice using PARCOR analysis

The degree of turbulent noise in the breathy voice of 25 patients with incomplete glottal closure was determined by PARCOR (PARtial autoCORrelation) analysis. From 10,000 acoustic data points, 44 PARCOR coefficients were calculated to form the residue wave which is representative of the glottal source. The power difference between the residue wave and the original acoustic wave was calculated in order to define a new measurement of acoustic power termed the turbulent noise ratio (TNR). The 25 patients were studied before and after Isshiki thyroplasty type I (IttI). The TNR became smaller in 24 of these patients following IttI, and corresponded closely with acoustic (Fukazawa's Br-Index), aerodynamic (Isshiki's AC/DC ratio), mean airflow rate during phonation, and videolaryngostroboscopic findings. Data affirm that the TNR accurately reflects the degree of turbulent noise at the glottal source.

Time series analysis of glottal airflow in normal and pathological phonation

Time series analysis of glottal airflow was carried out on 26 normal controls and 40 patients with voice disorders, using a modification of Isshiki's original technique which uses a hot-wire flowmeter, taking cycle-by-cycle fluctuations into consideration. The mean flow rate and mean AC/DC were shown to have significant differences among normal and patient groups. The standard deviations of AC/DC and AC/DC perturbation were calculated from the AC/DC value of 50 cycles and shown not to vary significantly among the normal and patient groups. The relationship between AC/DC and perceptual impression of voice was also studied among 20 selected patients with breathy voices. Using Spearman's rank correlation coefficient, this relationship was found to have statistical significance (P < .05).

H-Index: a new measure of glottal efficiency for the pathologic voice

Taking advantage of the extended dynamic range of digital analysis of voice the H-Index represents the first proposed acoustical measure of glottal efficiency. "Hi" /hai/ was chosen to evaluate glottal efficiency since it provides an excellent test of glottal transformation from voiceless to voiced sound energy, the upper vocal tract having a neutral effect. Fifteen individuals with normal voices and 30 patients with hoarse voices were asked to say "hi." The power ratio of /h/ to /a/ was calculated from peak power of each measure from the power envelope. Voice quality had a highly significant effect on measured values (P < .001). A high degree of correlation (P < .001) was found with the AC/DC ratio, a standard aerodynamic measure of glottal efficiency. The results indicate that the H-Index represents an excellent measure of glottal efficiency, obviating the need of invasive techniques or expensive, highly specialized equipment.

High-frequency power ratio of breathy voice

Digital technological advances have made detailed voice analysis possible. This report proposes, with the use of such equipment, a new method of quantifying differences in the high-frequency content of normal and breathy voices. The high-frequency power ratio, a ratio of high-frequency power versus total power, was calculated as the lower limit of the high-frequency range (Fc) and varied from 1 to 10 kHz. The high-frequency power ratio values of two groups, 16 normal and 24 breathy voice individuals, were then compared. Three breathy individuals were also studied after type I thyroplasty. High-frequency power ratio values measured at an Fc of 6 kHz significantly separated normal from breathy voices. The specifications provided are appropriate for both the commercial voice lab and for clinical resources. Furthermore, a high-frequency power ratio (6 kHz) is a useful tool for the evaluation of phonosurgery.

Relationship between left ventricular end-diastolic compliance and abnormal Doppler mitral filling in patients with coronary artery disease

Left ventricular end-diastolic compliance (LVEDC) and transmitral flow velocities were measured in 19 patients with coronary artery disease associated with hypertension and 10 normal subjects by LV catheterization and pulsed-Doppler echocardiography. LVEDC was much lower in the patient than in the normal subjects (P less than 0.01). The data showed that abnormal Doppler diastolic function such as elevated late diastolic peak flow velocity (PVA) and decreased LVEDC occurred in the patients at the same time. In addition, the negative correlation of PVA with LVEDC observed in normal controls but not in patients suggested that in patients with impaired diastolic filling, factors other than the decreased LVEDC itself must also participate in the development of diastolic dysfunction.