Today,noise control is of critical importance.In order to provide sound insulation,parameters such as Sound Transmission Loss(STL)and sound absorption coefficient are measured in environments such as impedance tubes,A...Today,noise control is of critical importance.In order to provide sound insulation,parameters such as Sound Transmission Loss(STL)and sound absorption coefficient are measured in environments such as impedance tubes,Alpha Cabin and echo chambers.However,the low number of accredited acoustic test rooms in Turkey and the high-test costs cause these tests to be performed in limited numbers.In this direction,test box similar to the Alpha Cabin designed aims to both reduce costs and perform tests in a healthy way using natural and recyclable materials,and to prevent damage to test devices caused by hard materials.In this study,samples with STL values above 30 dB at 500–8000 Hz.were selected and tested in the designed system.As a result,it was seen that the data were close to each other.The highest value was obtained as 49.13 dB at 4000 Hz.in a 2 cm thick gypsum board,gypsum and concave walnut shell sample(moving surface L_(1)).This situation provides an important contribution in terms of sound insulation by using natural and recyclable materials and the proposed test box,meeting the experimental criteria at low cost and in the field of noise control.展开更多
This study aimed to examine the performance of the Siegel-Tukey and Savage tests on data sets with heterogeneous variances. The analysis, considering Normal, Platykurtic, and Skewed distributions and a standard deviat...This study aimed to examine the performance of the Siegel-Tukey and Savage tests on data sets with heterogeneous variances. The analysis, considering Normal, Platykurtic, and Skewed distributions and a standard deviation ratio of 1, was conducted for both small and large sample sizes. For small sample sizes, two main categories were established: equal and different sample sizes. Analyses were performed using Monte Carlo simulations with 20,000 repetitions for each scenario, and the simulations were evaluated using SAS software. For small sample sizes, the I. type error rate of the Siegel-Tukey test generally ranged from 0.045 to 0.055, while the I. type error rate of the Savage test was observed to range from 0.016 to 0.041. Similar trends were observed for Platykurtic and Skewed distributions. In scenarios with different sample sizes, the Savage test generally exhibited lower I. type error rates. For large sample sizes, two main categories were established: equal and different sample sizes. For large sample sizes, the I. type error rate of the Siegel-Tukey test ranged from 0.047 to 0.052, while the I. type error rate of the Savage test ranged from 0.043 to 0.051. In cases of equal sample sizes, both tests generally had lower error rates, with the Savage test providing more consistent results for large sample sizes. In conclusion, it was determined that the Savage test provides lower I. type error rates for small sample sizes and that both tests have similar error rates for large sample sizes. These findings suggest that the Savage test could be a more reliable option when analyzing variance differences.展开更多
The mechanism of idiopathic ventricular tachycardia originating from the right ventricular outflow tract (RVOT) is not clear. Many clinical reports have suggested a mechanism of triggered activity. However, there ar...The mechanism of idiopathic ventricular tachycardia originating from the right ventricular outflow tract (RVOT) is not clear. Many clinical reports have suggested a mechanism of triggered activity. However, there are few studies investigating this be- cause of the technical difficulties associated with examining this theory. The L-type calcium current (/Ca-L), an important in- ward current of the action potential (AP), plays an important role in arrhythmogenesis. The aim of this study was to explore differences in the APs of right ventricular (RV) and RVOT cardiomyocytes, and differences in electrophysiological character- istics of the ICa-L in these myocytes. Rabbit RVOT and RV myocytes were isolated and their AP and Ic,-L were investigated us- ing the patch-clamp technique. RVOT cardiomyocytes had a wider range of AP duration (APD) than RV cardiomyocytes, with some markedly prolonged APDs and markedly shortened APDs. The markedly shortened APDs in RVOT myocytes were abolished by treatment with 4-AP, an inhibitor of the transient outward potassium current, but the markedly prolonged APDs remained, with some myocytes with a long AP plateau not repolarizing to resting potential. In addition, early afterdepolariza- tion (EAD) and second plateau responses were seen in RVOT myocytes but not in RV myocytes. RVOT myocytes had a high- er current density for/Ca-L than RV myocytes (RVOT (13.16±0.87) pA pF-1, RV (8.59±1.97) pA pF-1; P〈0.05). The ICa-L and the prolonged APD were reduced, and the EAD and second plateau response disappeared, after treatment with nifedipine (10 μmol L^-1), which blocks the Ica-L. In conclusion, there was a wider range of APDs in RVOT myocytes than in RV myocytes, which is one of the basic factors involved in arrhythmogenesis. The higher current density for ICa-L is one of the factors causing prolongation of the APD in RVOT myocytes. The combination of EAD with prolonged APD may be one of the mechanisms of RVOT-VT generation.展开更多
In the cultural stone heritage,progressive deteriorations develop over time with the effect of atmospheric processes.These deteriorations can reach to a significant degree that threaten the integrity of the monuments ...In the cultural stone heritage,progressive deteriorations develop over time with the effect of atmospheric processes.These deteriorations can reach to a significant degree that threaten the integrity of the monuments built from weak-strength rocks.In this study,it is aimed to determine the deteriorations caused by atmospheric processes on the monument surface in cultural heritage works built by carving into low-strength pyroclastic rocks by nondestructive tests(NDTs).To this end,two historic structures in the Kilistra Ancient City of Konya(Turkey)were selected.The index,strength,mineralogical and petrographic properties of the rocks,in which the monuments were carved,were first investigated.Then,contour scaling,crack,efflorescence and biodeterioration types were determined on the facades of the monuments.Later,NDT deterioration change maps were prepared based on the data obtained by performing the relative humidity,Schmidt hammer rebound(SHR),and P-wave velocity(Vp)measurements on the facades of the monuments.In the deterioration maps,it was determined that the SHR and Vp values of the rock were low in the capillary,infiltration,and crack zones with water penetration in the monuments built on low-strength pyroclastic rocks.However,deterioration was less in the regions with more limited water access according to zones.展开更多
文摘Today,noise control is of critical importance.In order to provide sound insulation,parameters such as Sound Transmission Loss(STL)and sound absorption coefficient are measured in environments such as impedance tubes,Alpha Cabin and echo chambers.However,the low number of accredited acoustic test rooms in Turkey and the high-test costs cause these tests to be performed in limited numbers.In this direction,test box similar to the Alpha Cabin designed aims to both reduce costs and perform tests in a healthy way using natural and recyclable materials,and to prevent damage to test devices caused by hard materials.In this study,samples with STL values above 30 dB at 500–8000 Hz.were selected and tested in the designed system.As a result,it was seen that the data were close to each other.The highest value was obtained as 49.13 dB at 4000 Hz.in a 2 cm thick gypsum board,gypsum and concave walnut shell sample(moving surface L_(1)).This situation provides an important contribution in terms of sound insulation by using natural and recyclable materials and the proposed test box,meeting the experimental criteria at low cost and in the field of noise control.
文摘This study aimed to examine the performance of the Siegel-Tukey and Savage tests on data sets with heterogeneous variances. The analysis, considering Normal, Platykurtic, and Skewed distributions and a standard deviation ratio of 1, was conducted for both small and large sample sizes. For small sample sizes, two main categories were established: equal and different sample sizes. Analyses were performed using Monte Carlo simulations with 20,000 repetitions for each scenario, and the simulations were evaluated using SAS software. For small sample sizes, the I. type error rate of the Siegel-Tukey test generally ranged from 0.045 to 0.055, while the I. type error rate of the Savage test was observed to range from 0.016 to 0.041. Similar trends were observed for Platykurtic and Skewed distributions. In scenarios with different sample sizes, the Savage test generally exhibited lower I. type error rates. For large sample sizes, two main categories were established: equal and different sample sizes. For large sample sizes, the I. type error rate of the Siegel-Tukey test ranged from 0.047 to 0.052, while the I. type error rate of the Savage test ranged from 0.043 to 0.051. In cases of equal sample sizes, both tests generally had lower error rates, with the Savage test providing more consistent results for large sample sizes. In conclusion, it was determined that the Savage test provides lower I. type error rates for small sample sizes and that both tests have similar error rates for large sample sizes. These findings suggest that the Savage test could be a more reliable option when analyzing variance differences.
文摘The mechanism of idiopathic ventricular tachycardia originating from the right ventricular outflow tract (RVOT) is not clear. Many clinical reports have suggested a mechanism of triggered activity. However, there are few studies investigating this be- cause of the technical difficulties associated with examining this theory. The L-type calcium current (/Ca-L), an important in- ward current of the action potential (AP), plays an important role in arrhythmogenesis. The aim of this study was to explore differences in the APs of right ventricular (RV) and RVOT cardiomyocytes, and differences in electrophysiological character- istics of the ICa-L in these myocytes. Rabbit RVOT and RV myocytes were isolated and their AP and Ic,-L were investigated us- ing the patch-clamp technique. RVOT cardiomyocytes had a wider range of AP duration (APD) than RV cardiomyocytes, with some markedly prolonged APDs and markedly shortened APDs. The markedly shortened APDs in RVOT myocytes were abolished by treatment with 4-AP, an inhibitor of the transient outward potassium current, but the markedly prolonged APDs remained, with some myocytes with a long AP plateau not repolarizing to resting potential. In addition, early afterdepolariza- tion (EAD) and second plateau responses were seen in RVOT myocytes but not in RV myocytes. RVOT myocytes had a high- er current density for/Ca-L than RV myocytes (RVOT (13.16±0.87) pA pF-1, RV (8.59±1.97) pA pF-1; P〈0.05). The ICa-L and the prolonged APD were reduced, and the EAD and second plateau response disappeared, after treatment with nifedipine (10 μmol L^-1), which blocks the Ica-L. In conclusion, there was a wider range of APDs in RVOT myocytes than in RV myocytes, which is one of the basic factors involved in arrhythmogenesis. The higher current density for ICa-L is one of the factors causing prolongation of the APD in RVOT myocytes. The combination of EAD with prolonged APD may be one of the mechanisms of RVOT-VT generation.
基金the grants from Scientific Research Foundation of Adıyaman University MU¨FYL/2017-0001.
文摘In the cultural stone heritage,progressive deteriorations develop over time with the effect of atmospheric processes.These deteriorations can reach to a significant degree that threaten the integrity of the monuments built from weak-strength rocks.In this study,it is aimed to determine the deteriorations caused by atmospheric processes on the monument surface in cultural heritage works built by carving into low-strength pyroclastic rocks by nondestructive tests(NDTs).To this end,two historic structures in the Kilistra Ancient City of Konya(Turkey)were selected.The index,strength,mineralogical and petrographic properties of the rocks,in which the monuments were carved,were first investigated.Then,contour scaling,crack,efflorescence and biodeterioration types were determined on the facades of the monuments.Later,NDT deterioration change maps were prepared based on the data obtained by performing the relative humidity,Schmidt hammer rebound(SHR),and P-wave velocity(Vp)measurements on the facades of the monuments.In the deterioration maps,it was determined that the SHR and Vp values of the rock were low in the capillary,infiltration,and crack zones with water penetration in the monuments built on low-strength pyroclastic rocks.However,deterioration was less in the regions with more limited water access according to zones.