Influence of Lung Volume on the Airflow-Intensity Relationship

1984 ◽  
Vol 27 (3) ◽  
pp. 430-435 ◽  
Author(s):  
Phillip Schneider ◽  
R. J. Baken
Keyword(s):  
Fundamental Frequency ◽  
Lung Volume ◽  
Significant Positive Correlation ◽  
Correlation Coefficients ◽  
Intrasubject Variability ◽  
Lung Inflation ◽  
Positive Correlation ◽  
Subglottal Pressure

This study reports airflow-intensity relationships observed in crescendo and decrescendo phonations produced at three fundamental frequency levels by l0 men. The purpose of the investigation was to study the possible influence of lung volume on airflow-intensity relationships. Of the 30 decrescendo phonations, 26 showed statistically significant correlation coefficients and none showed significant negative correlations. The crescendo phonations, however, showed greater inter- and intrasubject variability. Of the 30 crescendo phonations, 16 showed statistically significant positive correlation coefficients and 6 showed significant negative correlations. Because lung inflation varied directly with intensity in the decrescendo task and indirectly in the crescendo task, it was concluded that lung volume does influence the consistency and strength of relationship between airflow and intensity. The findings are discussed in terms of the influence of lung volume on the relative contributions of glottal resistance and expiratory force to the regulation of subglottal pressure.

Hot flash placebo responses: Related to baseline hot flash frequency?

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. 9628-9628
Author(s):  
J. M. Jones ◽  
C. L. Loprinzi ◽  
R. Qin ◽  
D. L. Barton
Keyword(s):  
Significant Positive Correlation ◽  
Hot Flashes ◽  
Placebo Response ◽  
Correlation Coefficients ◽  
Baseline Period ◽  
Percent Reduction ◽  
Hot Flash ◽  
Positive Correlation ◽  
Pubmed Search ◽  
Multiple Treatments

9628 Background: As multiple treatments have been studied for the management of hot flashes in randomized, controlled trials, hot flash placebo responses have been quite variable across trials. Based on observations of trial reports, it was hypothesized that the magnitude of placebo effect might correlate with the number of baseline hot flashes in different studies. The current project examines the effect of the baseline hot flash frequency required for study participation and also the actual number of baseline hot flashes observed as these individually relate to the eventual reductions of hot flash frequency observed in patients receiving placebos. Methods: Data were collected from placebo-controlled, double-blinded, randomized trials, identified by a PubMed search, which reported hot flash frequency at baseline, 4–6 weeks and 12 weeks. Trials were excluded if they had less than 20 participants completing the placebo arm. Data gathered, in each study, included the number of hot flashes required to enroll in the study, the average hot flash number during the baseline period, and the hot flash changes in the placebo arms of each study (percent reduction from the baseline period). A simple statistical analysis was conducted in a descriptive fashion since standard deviation was not available in many trials. Scatter plots and Pearson's correlation coefficients demonstrated the relationships between the placebo hot flash percent reduction from baseline and both the minimum required number of hot flashes at baseline, and the mean number of hot flashes at baseline. Results: 45 trials with 49 placebo arms were included in this analysis. A significant positive correlation was seen between the number of hot flashes required to enroll in a study and the percent reduction of hot flashes from baseline at 4–6 weeks (Rho = 0.481, p = 0.003). There was also a significant positive correlation between the number of hot flashes at baseline and the percent reduction of hot flashes from baseline at 4–6 weeks (Rho = 0.481, p= 0.002) and at 12 weeks (Rho = 0.573, p= 0.003). Conclusions: These data support that higher baseline hot flash enrollment requirements and also higher baseline hot flash frequencies are associated with an increased placebo response. No significant financial relationships to disclose.

scholarly journals Study Assessing the Quality of Quantification of Estrogen Receptor Protein Expression by Immunohistochemistry and Gene Expression in Breast Cancer

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Sas Leen ◽  
Van Laere Steven ◽  
Dierick Anne Marie ◽  
Duwel Valérie ◽  
De Pauw Annemie ◽  
...  
Keyword(s):  
Gene Expression ◽  
Significant Positive Correlation ◽  
Target Genes ◽  
Correlation Coefficients ◽  
Receptor Protein ◽  
Estrogen Receptor Protein ◽  
Positive Correlation ◽  
Esr1 Gene ◽  
Er Positive

Although immunohistochemistry (IHC) is a widely used technique to classify tumors in ER-positive versus ER-negative ones, interlab variabilities can occur. This study aims to investigate the influences of preanalytical and analytical factors on IHC results. For this purpose, the different steps of the preparation of IHC sections and scoring procedures were compared between two participating laboratories and a central lab. There was a significant positive correlation between the IHC results of the participating laboratories and those of the central lab (correlation coefficient > 0.600; P<0.05). Nevertheless, some discordant cases for immunostaining (5.3% for ER and 5.6% for PR) and for scoring (10.5% for PR) occur at site 1. Comparing IHC results with ESR1 gene expression results revealed a significant positive correlation (correlation coefficients > 0.769; P<0.05). PCR results of ER target genes showed some heterogeneity in the ER-signalling pathway. These results suggest that differences in the IHC procedure between these laboratories did not have a big influence on the end result. Nevertheless, discordant cases caused by preanalytical and analytical lab-specific procedures have been identified.

scholarly journals Validity of Four Commercial Bioelectrical Impedance Scales in Measuring Body Fat among Chinese Children and Adolescents

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Lin Wang ◽  
Stanley Sai-chuen Hui
Keyword(s):  
Children And Adolescents ◽  
Body Fat ◽  
Significant Positive Correlation ◽  
Correlation Coefficients ◽  
Bioelectrical Impedance ◽  
Chinese Children ◽  
Fat Percentage ◽  
Positive Correlation ◽  
Model C ◽  
Chinese Children And Adolescents

The aim of the study is to examine the validity in predicting body fat percentage (%BF) of different bioelectrical impedance (BIA) devices among Chinese children and adolescents. A total of 255 Chinese children and adolescents aged 9–19 years old participated in the study. %BF was assessed by BIA scales, namely, Biodynamics-310 (Model A), Tanita TBF-543 (Model B), Tanita BC-545 (Model C), and InBody 520 (Model D). Dual-energy X-ray absorptiometry (DXA) was used as the criterion measurement. Lin’s concordance correlation coefficients of estimated %BF between Model A, Model B, Model C, and DXA showed poor agreements for both genders. Moderate agreements for %BF were found between DXA and Model D measurements. In boys, differences in %BF were found between DXA and Model B and Model C. No significant %BF differences were found between Model A, Model D, and DXA. However, the two BIA analyzers showed a significant positive correlation between the bias and average %BF between BIA and DXA. In girls, differences in %BF were observed between Model B, Model C, Model D, and DXA. Model A and DXA showed no significant differences of %BF; however, the bias and the average %BF between the BIA and DXA had a significant positive correlation. Using embedded equations in BIA devices should be validated in assessing the %BF of Chinese children and adolescents.

A comparison of two methods for evaluating surface properties of the lung

1965 ◽  
Vol 20 (4) ◽  
pp. 782-784 ◽  
Author(s):  
W. F. Howatt ◽  
L. B. Strang
Keyword(s):  
Surface Tension ◽  
Significant Positive Correlation ◽  
Correlation Coefficients ◽  
Stability Index ◽  
Positive Correlation ◽  
Tension Properties ◽  
Fetal Lamb ◽  
Stability Method ◽  
Positive Correlation Coefficient ◽  
Surface Balance

Indices of the surface tension properties of fetal lamb lungs were obtained by the bubble stability method and from direct measurements of a lung extract on a Langmuir-Wilhelmy balance. A comparison of 102 determinations by each method on 31 fetal lamb lungs gave a statistically significant positive correlation coefficient. A comparison of the surface balance index with a pressure-volume deflation index and with gestation and of the bubble stability index with gestation gave statistically significant positive correlation coefficients. Storage by freezing for 21—112 days did not alter either index of surface tension. lung surface tension; measurement of lung surface tension; surface balance; lung bubbles Submitted on October 15, 1964

scholarly journals Heavy Metal Distribution in Street Dust of Urban and Industrial Areas in Jeddah, Saudi Arabia

2012 ◽  
Vol 23 (2) ◽  
pp. 55-75
Author(s):  
Mansour A. Al Ghamdi Mansour A. Al Ghamdi
Keyword(s):  
Heavy Metals ◽  
Saudi Arabia ◽  
Urban Area ◽  
Significant Positive Correlation ◽  
Correlation Coefficients ◽  
Industrial Area ◽  
Street Dust ◽  
Positive Correlation ◽  
Main Streets ◽  
Cu And Zn

The concentrations of heavy metals namely: Pb, Ni, Cd, Cr, Cu, Zn, Fe and Mn were measured in street dust samples. The samples were collected from the urban (Aljamaa district, main streets and substreets) and industrial areas of Jeddah city, Saudi Arabia. The concentrations of the measured metals were significantly higher in the main streets of the urban area than those found in the industrial area and substrates of the urban area. However, Pb was found in the highest levels in industrial area. The concentrations of the individual metals in street dust collected from the main streets and substreets of the urban area and industrial area averaged 70.36, 53.51 and 105.76 µg/g for Pb; 39.71, 24.00 and 27.28 µg/g for Ni; 2.24, 1.32 and 1.57 µg/g for Cd; 72.93, 40.10 and 47.67 µg/g for Cr; 125.52, 83.32 and 93.66 µg/g for Cu; 340.85, 214.10 and 240.50 µg/g for Zn; 10199.42, 7678.84 and 7918.42 µg/g for Fe and 514.15, 389.69 and 400.64 µg/g for Mn, respectively. The ratios of main streets/substreets metal concentration in the urban area were 1.31, 1.65, 1.70, 1.82, 1.51, 1.59, 1.33 and 1.32 for Pb, Ni, Cd, Cr, Cu, Zn, Fe and Mn, respectively. The mean concentrations of measured heavy metals in street dust from both study areas were lower / higher or similar to those detected in other cities of the world. The average concentrations of Cu and Zn in street dust of the main street dusts of the urban area exceeded the permissible limit value of soil. Significant positive correlation coefficients were found between the concentrations of Cr, Cd, Cu and Zn and also between the concentrations of Fe, Mn and Ni, Cr, Cu and Zn in the street dust of the urban area. On the other hand, insignificant positive correlation coefficients were found between the concentrations of Pb and other metals in street dust of the urban area. In the industrial area, significant positive correlation coefficients were found between the concentrations of heavy metals in the street dust.

Aerodynamic and Acoustic Voice Measures Before and After an Acute Public Speaking Stressor

2020 ◽  
Vol 63 (10) ◽  
pp. 3311-3325
Author(s):  
Brittany L. Perrine ◽  
Ronald C. Scherer
Keyword(s):  
Fundamental Frequency ◽  
Salivary Cortisol ◽  
Public Speaking ◽  
Stress System ◽  
Before And After ◽  
Subglottal Pressure ◽  
Response To Stress ◽  
System Activation ◽  
Speaking Fundamental Frequency ◽  
Pituitary Adrenal Axis

Purpose The goal of this study was to determine if differences in stress system activation lead to changes in speaking fundamental frequency, average oral airflow, and estimated subglottal pressure before and after an acute, psychosocial stressor. Method Eighteen vocally healthy adult females experienced the Trier Social Stress Test (TSST) to activate the hypothalamic–pituitary–adrenal axis. The TSST includes public speaking and performing mental arithmetic in front of an audience. At seven time points, three before the stressor and four after the stressor, the participants produced /pa/ repetitions, read the Rainbow Passage, and provided a saliva sample. Measures included (a) salivary cortisol level, (b) oral airflow, (c) estimated subglottal pressure, and (d) speaking fundamental frequency from the second sentence of the Rainbow Passage. Results Ten of the 18 participants experienced a hypothalamic–pituitary–adrenal axis response to stress as indicated by a 2.5-nmol/L increase in salivary cortisol from before the TSST to after the TSST. Those who experienced a response to stress had a significantly higher speaking fundamental frequency before and immediately after the stressor than later after the stressor. No other variable varied significantly due to the stressor. Conclusions This study suggests that the idiosyncratic and inconsistent voice changes reported in the literature may be explained by differences in stress system activation. In addition, laryngeal aerodynamic measures appear resilient to changes due to acute stress. Further work is needed to examine the influence of other stress systems and if these findings hold for dysphonic individuals.

scholarly journals Impact of Climatic Conditions on the Resveratrol Concentration in Blend of Vitis vinifera L. cvs. Barbera and Croatina Grape Wines

Molecules ◽  
2021 ◽  
Vol 26 (2) ◽  
pp. 401
Author(s):  
Gabriele Rocchetti ◽  
Federico Ferrari ◽  
Marco Trevisan ◽  
Luigi Bavaresco
Keyword(s):  
Vitis Vinifera ◽  
Correlation Coefficients ◽  
Climatic Conditions ◽  
Meteorological Conditions ◽  
Vitis Vinifera L ◽  
Red Wines ◽  
Bioclimatic Indices ◽  
Positive Correlation ◽  
Mean Temperature ◽  
Production Areas

The aim of this work was to investigate the effect of meteorological conditions on resveratrol concentration of red wines produced in Piacenza viticultural region (Italy). In this regard, six representative estates producing Colli Piacentini Gutturnio DOC (a blend of V. vinifera L. cvs. Barbera and Croatina) vintage wines were analysed for trans- and cis-resveratrol over an 8-year period (1998–2005). Grapes were taken from the same vineyard in each estate by using the same enological practices over the entire investigated period. The meteorological conditions corresponding to the production areas were recorded, and bioclimatic indices were calculated as well. Overall, cis-resveratrol concentration was negatively correlated to Huglin index and August mean temperature, whilst positive correlation coefficients were found when considering the Selianinov index and the rainfall of September.

scholarly journals Correlates of SARS-CoV-2 Variants on Deaths, Case Incidence and Case Fatality Ratio among the Continents for the Period of 1 December 2020 to 15 March 2021

Genes ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 1061
Author(s):  
Wajdy J. Al-Awaida ◽  
Baker Jawabrah Al Hourani ◽  
Samer Swedan ◽  
Refat Nimer ◽  
Foad Alzoughool ◽  
...  
Keyword(s):  
Negative Correlation ◽  
Significant Positive Correlation ◽  
Vaccine Development ◽  
Case Fatality ◽  
Significant Negative Correlation ◽  
Reference Sequence ◽  
Genome Sequences ◽  
Positive Correlation ◽  
Case Fatality Ratio ◽  
Epidemiological Surveys

The outbreak of coronavirus disease 2019 (COVID-19), by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has quickly developed into a worldwide pandemic. Mutations in the SARS-CoV-2 genome may affect various aspects of the disease including fatality ratio. In this study, 553,518 SARS-CoV-2 genome sequences isolated from patients from continents for the period 1 December 2020 to 15 March 2021 were comprehensively analyzed and a total of 82 mutations were identified concerning the reference sequence. In addition, associations between the mutations and the case fatality ratio (CFR), cases per million and deaths per million, were examined. The mutations having the highest frequencies among different continents were Spike_D614G and NSP12_P323L. Among the identified mutations, NSP2_T153M, NSP14_I42V and Spike_L18F mutations showed a positive correlation to CFR. While the NSP13_Y541C, NSP3_T73I and NSP3_Q180H mutations demonstrated a negative correlation to CFR. The Spike_D614G and NSP12_P323L mutations showed a positive correlation to deaths per million. The NSP3_T1198K, NS8_L84S and NSP12_A97V mutations showed a significant negative correlation to deaths per million. The NSP12_P323L and Spike_D614G mutations showed a positive correlation to the number of cases per million. In contrast, NS8_L84S and NSP12_A97V mutations showed a negative correlation to the number of cases per million. In addition, among the identified clades, none showed a significant correlation to CFR. The G, GR, GV, S clades showed a significant positive correlation to deaths per million. The GR and S clades showed a positive correlation to number of cases per million. The clades having the highest frequencies among continents were G, followed by GH and GR. These findings should be taken into consideration during epidemiological surveys of the virus and vaccine development.

scholarly journals Comparative Evaluation of Adenoids, Upper Airway, and Tongue Using “Predictors of Difficult Airways” in Class II Division 1 and Division 2 Cases with Class I Cases: Prospective In Vivo Observational Study

2021 ◽  
pp. 030157422096341
Author(s):  
Smita Mangesh Choudhari ◽  
Sunita Shrivastav
Keyword(s):  
Significant Positive Correlation ◽  
Upper Airway ◽  
Class Ii ◽  
Class I ◽  
Positive Correlation ◽  
Division 1 ◽  
Difficult Airways ◽  
Mandibular Protrusion ◽  
Division 2 ◽  
Class Ii Division 1

Introduction: Altered nasorespiratory function leads to altered craniofacial growth. Thus, airway evaluation is important for preventive, interceptive, and corrective orthodontic treatment. The aim of this study was to evaluate and compare adenoids, the upper airway, the tongue, and mandibular dimensions using “predictors of difficult airways” in class II division 1 and class II division 2 cases with class I cases. Method: Sixty subjects of age 15 to 18 years were divided into 3 groups (group 1: class I cases; group 2: class II division 1 cases; and group 3: class II division 2 cases) based on cephalometric parameters, with 20 cases in each group. Cephalometric evaluation of adenoids and the nasopharyngeal airway was done using the Handelman–Osborne area method. Upper and lower airway evaluation was done using McNamara’s linear method. “Predictors of difficult airways” were used for evaluation of the airway, which included nasal competency, the Mallampati scale, mandibular length, mandibular protrusion, and the thyromental distance. Results: The present study found a significant positive correlation between the grades of nasal competency and percentage adenoid wall area, and a significant negative correlation between the grades of nasal competency and the upper airway. There was a significant positive correlation between the grades of nasal competency and mandibular length, and a significant positive correlation between the grades of mandibular protrusion and mandibular length. There was a significant positive correlation between the grades of the thyromental distance and mandibular length. Conclusion: It was concluded that the “predictors of difficult airways” would be helpful in early diagnosis and identification of potential risk factors that may cause “breathing disorders”–related malocclusions and later on increase the risk of developing OSA.

Changes in duplex ultrasound parameters during maturation according to arteriovenous access types in incident hemodialysis patients

2021 ◽  
pp. 112972982110052
Author(s):  
Jae Jin Lee ◽  
Sun Ryoung Choi ◽  
Eun Ju Lee ◽  
Ha Youn Yang ◽  
Seon Ha Baek ◽  
...  
Keyword(s):  
Pulsatility Index ◽  
Significant Positive Correlation ◽  
Duplex Ultrasound ◽  
Hemodialysis Patients ◽  
Hemodynamic Parameters ◽  
Positive Correlation ◽  
Arteriovenous Access ◽  
Artery Flow ◽  
Ultrasound Parameters ◽  
Av Graft

Background: Little is known about the changes in hemodynamic parameters during arteriovenous (AV) access maturation using duplex ultrasound according to radiocephalic fistula (RCF), brachiocephalic fistula (BCF), and AV graft (AVG) in incident hemodialysis (HD) patient. The objective of this study was to evaluate changes and differences in brachial artery flow rate (BAFR) and related parameters affecting maturation by duplex ultrasound in incident HD patients according to access type. Methods: This study was an observational study conducted from March 2019 to October 2020. During the study period, 109 incident patients underwent new AV access creation, of which 100 were included in the study. The duplex ultrasound was performed on the day prior to access creation, further, day 1, 2 weeks, and 4 weeks later after access creation in incident HD patients. Results: Among all the patients, 38 (38%) received BCF, while 26 (26%) underwent RCF. Of the patients with AVG, 18 (50%) had a forearm loop AVG. The overall mean age was 62.2 ± 13.8 years (range, 32–89). The BAFR increased about 6.9 times in the RCF, 17.4 times in the BCF, and 19.5 times in the AVG at day 1. The median BAFR measured on day 1 was 580.4 mL/min for RC, 1029.0 mL/min for BC, and 1133.0 mL/min for AVG. Relative to the values measured in week 4, the BAFR on day 1 was 69.5% in RCF, 90.6% in BCF, and 93.9% in AVG. The acceleration decreased most significantly on day 1( p < 0.05). The acceleration time increased significantly on day 1 ( p < 0.05) and beyond during maturation in the RCF and BCF. The BAFR of the RCF had a significantly negative correlation with the pulsatility index. The BAFR of the BCF showed a significantly positive correlation with the systolic and diastolic blood pressure but negatively correlated with pulse rate. The BAFR of the AVG showed a significant positive correlation with the diameter of the outflow vein. Conclusions: There were differences in the clinical and duplex parameters during maturation according to access type. The most dramatic changes of duplex parameters were on the day after AV access creation regardless of AV access types. Though RCF had a lower BAFR rate compared to BCF and AVG, it already had a sufficient BAFR required for adequate HD treatment the day after creation. The BAFR of BCF was not different from that of AVG.

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