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2022 ◽  
Author(s):  
Melih Şahinöz ◽  
Hüseyin Yılmaz ARUNTAŞ ◽  
Metin GÜRÜ

Abstract This paper deals with the processing of polymer wood composite material from pine cone and the binder of phenol formaldehyde/PVAc/molasses and improvement of its properties. The production of pine cone based polymer binding and molasses added composite material, and the development of the non-flammability, insect attack and water resistance properties of this material has been studied in the research. To this end, pine cone, polyvinyl acetate (PVAc), phenol-formaldehyde, molasses, hemp fiber and waste colemanite have been used in the production of composite materials. It is aimed to produce a cheaper composite material less harmful to human health using plant based waste materials. According to the results of the flexural strength test conducted in the laboratory, the most suitable composite material producing parameters were detected as 0.25 filler/binder (f/b) ratio, 35% molasses ratio, 100°C molding pressure temperature, 49 kg/cm2 molding pressure, 240 µm mean particle size, 20 minutes for molding pressure time, 20% PF ratio and 0.5% hemp fiber ratio. It was determined that molasses could be used at a ratio of 35% for producing composite materials and, PF resin and hemp fiber samples provide the necessary water resistance. It was observed that the colemanite waste used in the mixture adds the nonflammability property to the composite material and decreases flexural strength and screw withdrawal strength.


2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Muhammad Ishfaq ◽  
Azmat Ullah ◽  
Awais Ahmed ◽  
Sarfraz Ali ◽  
Syed Muhmmad Ali ◽  
...  

This research intends to numerically study the out-of-plane behaviour of confined dry-stacked masonry (CDSM) walls against blast loading. CDSM is a mortarless interlocking masonry system consisting of Hydraform blocks laid in stretcher bond with reinforced concrete (RC) confining elements. A nonlinear numerical model is developed using advanced finite element hydrocode ANSYS-Autodyn to study the response of CDSM walls subjected to explosive loads. Four different test cases using a charge weight of 4 kg, 8 kg, 12 kg, and 16 kg of Wabox explosive are investigated numerically. The results obtained from numerical simulation are validated with the experimental tests results. The numerical results are found in good agreement with the experimental results. The ability of the numerical model is studied to correctly predict the pressure-time history in pressure gauges installed on walls and compared with experimental data. Peak incident overpressures obtained in these numerical tests ranged from 240 to 1000 kPa. Likewise, the damage patterns obtained from the numerical simulations are compared with available experimental results which show a satisfactory agreement. This study helps to check the response of CDSM structures against blast load which can be used for the construction of blast resisting design of buildings.


2021 ◽  
Vol 11 (2) ◽  
pp. 264-272
Author(s):  
Agustiawan Agustiawan ◽  
Rama Gita Suci ◽  
Rahmatul Fauziah

The purpose of this study was to partially examine the effect of compliance pressure, time budget pressure, and auditor experience on audit assessments during the Covid-19 Pandemic. Sampling in this study using non-probability sampling with saturated samples. Respondents in this week's study were auditors of new public accounting firms. This research method is a quantitative method. The data analysis technique used is multiple linear regression analysis. The results of this study indicate that compliance pressure, time budget pressure, and auditor experience each have an effect on audit assessments during the Covid-19 pandemic.


2021 ◽  
Vol 25 (4) ◽  
pp. 282-289
Author(s):  
Tatjana Yu. Zotova ◽  
Anastasiya A. Lukanina ◽  
Mikhail L. Blagonravov

Relevance . The study of the daily dynamics of blood pressure in arterial hypertension both on the basis of the daily index and on the basis of the time load is a relevant task, since, these indicators are associated in the literature with stable changes in the neurohumoral regulation of the cardiovascular system in arterial hypertension . The aim of the study was to compare data of the time load in patients with arterial hypertension , depending on the nocturnal blood pressure profile, with integrative indicators of the activity of the cardiovascular system in the form of a Circadian index, a structural point of blood pressure, double product. Materials and Methods. The study included 72 patients who were treated at the City Clinical Hospital No 13 in Moscow and signed a voluntary consent to participate in the research and the processing of personal data. Inclusion criteria: arterial hypertension. Exclusion criteria: metabolic syndrome, secondary forms of arterial hypertension and concomitant pathology. Depending on the daily index (DI10% and DI10%) patients were divided into 2 groups: 1 group (N= 32): patients with arterial hypertension without nocturnal decrease in blood pressure (non-dippers and night-pickers100%); Group 2 (N = 40): patients with arterial hypertension who had a nocturnal decrease in blood pressure (dippers and over dippers 100%). All patients and members of the control group (N=15) underwent daily monitoring of blood pressure (24-hour Arterial Blood Pressure Monitoring). The data were statistically processed to determine the 5% level of significance of differences (p0.05) (Students test). In the comparative analysis of integrative indicators at day and at night, a variance analysis was applied. Results and Discussion . As a result of the study, it was found that the values of Circadian Index for blood pressure vary depending on the type of night decrease in blood pressure and the blood pressure time load, while daily index and structural point of blood pressure remain on the same level as a reflection of the hemodynamic allostasis existing in both groups. Conclusion. Reflection of the allostatic load on hemodynamics is change of values of double product and of the structural point of blood pressure compared with the control group. These changes are not associated with the peculiarities of the nocturnal blood pressure profile in patients with hypertension without metabolic syndrome.


Measurement ◽  
2021 ◽  
pp. 110583
Author(s):  
MJ Cervantes ◽  
G Dunca ◽  
B Mulu ◽  
PP Jonsson
Keyword(s):  

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Davide Chiumello ◽  
Elena Chiodaroli ◽  
Silvia Coppola ◽  
Simone Cappio Borlino ◽  
Claudia Granata ◽  
...  

Abstract Background The use of awake prone position concomitant to non-invasive mechanical ventilation in acute respiratory distress syndrome (ARDS) secondary to COVID-19 has shown to improve gas exchange, whereas its effect on the work of breathing remain unclear. The objective of this study was to evaluate the effects of awake prone position during helmet continuous positive airway pressure (CPAP) ventilation on inspiratory effort, gas exchange and comfort of breathing. Methods Forty consecutive patients presenting with ARDS due to COVID-19 were prospectively enrolled. Gas exchange, esophageal pressure swing (ΔPes), dynamic transpulmonary pressure (dTPP), modified pressure time product (mPTP), work of breathing (WOB) and comfort of breathing, were recorded on supine position and after 3 h on prone position. Results The median applied PEEP with helmet CPAP was 10 [8–10] cmH2O. The PaO2/FiO2 was higher in prone compared to supine position (Supine: 166 [136–224] mmHg, Prone: 314 [232–398] mmHg, p < 0.001). Respiratory rate and minute ventilation decreased from supine to prone position from 20 [17–24] to 17 [15–19] b/min (p < 0.001) and from 8.6 [7.3–10.6] to 7.7 [6.6–8.6] L/min (p < 0.001), respectively. Prone position did not reduce ΔPes (Supine: − 7 [− 9 to − 5] cmH2O, Prone: − 6 [− 9 to − 5] cmH2O, p = 0.31) and dTPP (Supine: 17 [14–19] cmH2O, Prone: 16 [14–18] cmH2O, p = 0.34). Conversely, mPTP and WOB decreased from 152 [104–197] to 118 [90–150] cmH2O/min (p < 0.001) and from 146 [120–185] to 114 [95–151] cmH2O L/min (p < 0.001), respectively. Twenty-six (65%) patients experienced a reduction in WOB of more than 10%. The overall sensation of dyspnea was lower in prone position (p = 0.005). Conclusions Awake prone position with helmet CPAP enables a reduction in the work of breathing and an improvement in oxygenation in COVID-19-associated ARDS.


2021 ◽  
Author(s):  
Maria Ruiz-Ramos ◽  
Ángel Manuel Orejana-García ◽  
Ignacio Vives-Merino ◽  
Carmen Bravo-Llatas ◽  
José Luis Lázaro-Martínez ◽  
...  

Abstract Background: Metatarsalgia is a common foot condition. The metatarsophalangeal stabilizing taping technique described by Yu et al. has shown good clinical results as a provisional treatment in propulsive metatarsalgia. 35 The Fixtoe Device®, a novel orthopedic device, intends to simulate stabilizing tape. However, to date, there is no evidence of its effectiveness.Methods: The aim of this study was to assess plantar pressure changes using the Fixtoe Device®, in comparison with the traditional method (stabilizing tape) in a young, healthy sample thorough a cross-sectional study. Maximal pressure (Kpa) and pressure-time integral (Kpa/s) in the second metatarsal head were measured in twenty-four healthy volunteers. Registers were taken in four different conditions: barefoot, traditional stabilizing tape, Fixtoe Device® without metatarsal pad, and Fixtoe Device® with metatarsal pad. Results: Mean second metatarsal head maximal pressure and mean pressure-time integral showed statistical difference among the four analyzed conditions (p < 0.0001 in both cases). The improvement in maximal pressure and pressure-time integral obtained in each intervention also showed significance (p < 0.0001 in both cases). Comparing the improvement of the Fixtoe Device® with and without metatarsal pad with that of tape condition showed a moderate to high and moderate effect size for both peak pressure and pressure-time integral reduction.Conclusions: The Fixtoe Device® reduces median maximal pressure and median pressure-time integral under the second metatarsal head in healthy young individuals. The Fixtoe Device® shows higher effectiveness than the traditional second metatarsophalangeal joint stabilizing taping technique. To our knowledge, this is the first investigation proving the effectiveness of the recently developed Fixtoe Device® in terms of plantar pressure modification, which leads the way to its use in clinics.


2021 ◽  
Vol 72 (4) ◽  
pp. 347-352
Author(s):  
Ahad Furugi ◽  
Fatih Yapici

Optimization of process conditions in oriented strand board (OSB) manufacturing is a very important issue for both reducing cost and improving the quality of panels. Taguchi experimental design technique was applied to determination and optimization of the most influential controlling parameters of OSB panels such as press condition (pressure-time-temperature) and the ratio of adhesive parameters on modulus of elasticity (MOE). The value of the MOE is one of the very important mechanical properties of OSB panels. For this purpose, several experiments were conducted according to Taguchi L27 orthogonal design. The signal-to-noise (S/N) and the analysis of variance (ANOVA) were used to find the optimum levels and to indicate the impact of the controlling parameters on MOE. A verification test was also performed to prove the effectiveness of Taguchi technique. Since the predicted and the measured values were very close to each other, it was concluded that the Taguchi method was very successful in the optimization of effective parameters in OSB’s manufacturing.


2021 ◽  
Author(s):  
Thomas Poulard ◽  
Damien Bachasson ◽  
Quentin Fossé ◽  
Marie-Cécile Niérat ◽  
Jean-Yves Hogrel ◽  
...  

Background The relationship between the diaphragm thickening fraction and the transdiaphragmatic pressure, the reference method to evaluate the diaphragm function, has not been clearly established. This study investigated the global and intraindividual relationship between the thickening fraction of the diaphragm and the transdiaphragmatic pressure. The authors hypothesized that the diaphragm thickening fraction would be positively and significantly correlated to the transdiaphragmatic pressure, in both healthy participants and ventilated patients. Methods Fourteen healthy individuals and 25 mechanically ventilated patients (enrolled in two previous physiologic investigations) participated in the current study. The zone of apposition of the right hemidiaphragm was imaged simultaneously to transdiaphragmatic pressure recording within different breathing conditions, i.e., external inspiratory threshold loading in healthy individuals and various pressure support settings in patients. A blinded offline breath-by-breath analysis synchronously computed the changes in transdiaphragmatic pressure, the diaphragm pressure-time product, and diaphragm thickening fraction. Global and intraindividual relationships between variables were assessed. Results In healthy subjects, both changes in transdiaphragmatic pressure and diaphragm pressure-time product were moderately correlated to diaphragm thickening fraction (repeated measures correlation = 0.40, P &lt; 0.0001; and repeated measures correlation = 0.38, P &lt; 0.0001, respectively). In mechanically ventilated patients, changes in transdiaphragmatic pressure and thickening fraction were weakly correlated (repeated measures correlation = 0.11, P = 0.008), while diaphragm pressure-time product and thickening fraction were not (repeated measures correlation = 0.04, P = 0.396). Individually, changes in transdiaphragmatic pressure and thickening fraction were significantly correlated in 8 of 14 healthy subjects (ρ = 0.30 to 0.85, all P &lt; 0.05) and in 2 of 25 mechanically ventilated patients (ρ = 0.47 to 0.64, all P &lt; 0.05). Diaphragm pressure-time product and thickening fraction correlated in 8 of 14 healthy subjects (ρ = 0.41 to 0.82, all P &lt; 0.02) and in 2 of 25 mechanically ventilated patients (ρ = 0.63 to 0.66, all P &lt; 0.01). Conclusions Overall, diaphragm function as assessed with transdiaphragmatic pressure was weakly related to diaphragm thickening fraction. The diaphragm thickening fraction should not be used in healthy subjects or ventilated patients when changes in diaphragm function are evaluated. Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New


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