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Inter-Fraction Analysis of One Week Hypo-Fractionation of Deep Inspiration Breath Hold (DIBH) Technique for Left Sided Breast Cancer Radiation Treatment
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作者 Ntombela N. Lethukuthula Mathuthu Manny Nyathi Mpumelelo 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2024年第3期41-52,共12页
The aim of this study was to investigate the inter-fraction variations, patient comfort and knowledge at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH). The differences in set-up that occurred between treatme... The aim of this study was to investigate the inter-fraction variations, patient comfort and knowledge at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH). The differences in set-up that occurred between treatment sessions for the left sided breast patients were observed and recorded. Measurements of routine set-up variation for 24 patients were performed by matching the cone beam computed tomography (CBCT) and the planning computed tomography (CT). Scans of all five fractions per patient were used to quantify the setup variations with standard deviation (SD) in all the three directions (anterior posterior, left right, and superior inferior). The patients DIBH comfort and knowledge was also evaluated. The average translational errors for the anterior posterior (AP, z), left-right (LR, x), and Superior-inferior (SI, y) directions were 0.40 cm, 0.40 cm, and 0.40 cm, respectively. The translation variation of the three directions showed statistical significance (P < 0.05). On comfort and knowledge investigation, among all participants, 80% moderately agreed that the therapist’s instructions for operating the deep inspiration breath hold (DIBH) technique were easy to understand, and 63.33% indicated that their comfort with the DIBH technique was neutral or average. The inter-fraction variations in patients with left-sided breast cancer were qualitatively analyzed. Significant shifts between CBCT and planning CT images were observed. The daily treatment verification could assist accurate dose delivery. 展开更多
关键词 Breast Cancer Deep inspiration breath Hold Hypo-Fractionation Inter-Fraction
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Static Stretching Combined with Conscious Slower Breathing May Increase Parasympathetic Activity and Reduce Stress in Adult Women
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作者 Mami Sakurai Yasushi Ikarashi +3 位作者 Masahiro Tabuchi Ailing Hu Takuji Yamaguchi Hiroyuki Kobayashi 《Health》 2024年第3期242-256,共15页
Background: Women are thought to be more susceptible to stress than men in a stressful society, and reducing stress is crucial for women to maintain their health. Static stretching (SST) is applied in various fields t... Background: Women are thought to be more susceptible to stress than men in a stressful society, and reducing stress is crucial for women to maintain their health. Static stretching (SST) is applied in various fields to not only increase muscle flexibility but also reduce stress. Additionally, conscious slower breathing (CSB) predominates parasympathetic activity, causing a relaxing effect. These results indicate that combining SST and CSB may be more useful in reducing stress. However, to the best of our knowledge, the effect of this combination remains unclear. Objective: This study aimed to elucidate the effects of the combination of SST and CSB on autonomic activity and stress in adult women. Methods: Eleven healthy Japanese adult female participants performed SST with nonconscious natural breathing for 20 min. The same participants performed SST in combination with CSB (2 s inspiratory and 4 s expiratory) for 20 min on another day. Salivary cortisol and chromogranin A levels were measured before and after stretching as stress markers of the hypothalamic-pituitary-adrenal axis and sympathetic nervous system. The coefficient of variation of the R-R interval (CVR-R) and high-frequency component (HF), which reflect parasympathetic nerve activity, and heart rate and low-frequency component (LF)/HF ratio, which reflect sympathetic nerve activity, were measured before, during, and after stretching. Results: SST decreased cortisol levels but with no significant changes in chromogranin A, heart rate, CVR-R, HF, or LF/HF ratio. The combination of SST and CSB increased CVR-R and HF levels in addition to decreasing cortisol levels but with no significant changes in chromogranin A, heart rate, or LF/HF levels. Conclusion: These results indicate that the combination of SST and CSB may increase parasympathetic activity and reduce stress. However, future randomized controlled trials with larger sample sizes should support this conclusion. 展开更多
关键词 Static Stretching Conscious Slower breathing Autonomic Activity Heart Rate Variability STRESS
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Analysis of the Effect of Psychological Nursing Combined with Breathing Exercises in Improving Lung Function in Patients with Pneumoconiosis
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作者 Jing Huang 《Occupational Diseases and Environmental Medicine》 2024年第1期35-40,共6页
Objective: To analyze the effect of psychological nursing combined with breathing exercises on lung function of patients with pneumoconiosis, and to analyze the methods. A total of 64 cases of pneumoconiosis admitted ... Objective: To analyze the effect of psychological nursing combined with breathing exercises on lung function of patients with pneumoconiosis, and to analyze the methods. A total of 64 cases of pneumoconiosis admitted from January 2020 to December 2022 were divided into the reference group and the experimental group by random numerical table. On the basis of symptomatic treatment, the control group was combined with conventional nursing measures and breathing exercises, while the experimental group was treated with psychological nursing on the basis of the control group, and the pulmonary function indexes and adverse mood of the two groups before and after nursing were compared. Results: There was no difference in SAS score, SDS score and pulmonary function indexes between the two groups before intervention (P > 0.05), and the SAS score in the experimental group was the SDS score was lower than that of the control group, and FEV1, FEV1% and FEV1/FVC were higher than those of the control group, and the P < 0.05 was lower. 展开更多
关键词 PNEUMOCONIOSIS Psychological Nursing breathing Exercises Lung Function
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Infant’s Sigh Breathing Matters—The Role of the Hering-Breuer Deflation Reflex in Bronchial Decongestion
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作者 Karine Truflandier Kevin Albert Jean-Jacques Moraine 《Open Journal of Therapy and Rehabilitation》 2024年第3期197-212,共16页
Background: The prolonged slow expiratory (PSE) technique can induce sigh breaths related to the Hering-Breuer reflex in children.PSE is a specific chest physiotherapy technique often used in children to help with the... Background: The prolonged slow expiratory (PSE) technique can induce sigh breaths related to the Hering-Breuer reflex in children.PSE is a specific chest physiotherapy technique often used in children to help with the clearance of secretions, reduce pulmonary obstruction and decrease ventilatory effort. Purpose: The main objective of this review was to synthesize and clarify the existing knowledge of the physiological mechanism behind the Hering-Breuer reflex and its utility in the PSE technique. The secondary objective was to provide an overview of PSE which is probably the main mechanical feature for mucus clearance in infants and to identify gaps and any further research required. Method: A comprehensive literature search was performed using PubMed/MEDLINE and Ovid EMBASE, from 1968 to January 2024, using search terms relating to “Interaction of Hering-Breuer reflex and chest physiotherapy therapy, sigh breath in infants and prolonged slow expiration technique” to create an overview of the advances and gaps in current knowledge of PSE. Result: The data obtained following treatment with PSE maneuvers in infants with histories of recurrent wheezing shows that the presence of sighs could be the main active principle of treatment. Conclusion: Changes in volume induced by PSE technique and, effects from crying may stimulate the Hering-Breuer deflation reflex and sighs in turn improving alveolar ventilation as well as lung volume in infants. 展开更多
关键词 Hering-Breuer (HB) Reflex Sigh breath INFANTS Prolonged Slow Expiration Technique Large Volume Chest Physiotherapy
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Effects of relaxation breathing exercise on fatigue and cortisol level among Indonesian gynecological cancer patients undergoing chemotherapy:a pilot study
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作者 Mulhaeriah Mulhaeriah Mohammad Syafar Sangkala +1 位作者 Syahrul Syahrul Rezki Wahyuni 《Frontiers of Nursing》 2024年第2期201-208,共8页
Objective:This study aimed to determine the effect of the relaxation breathing exercise(RBE)on fatigue and cortisol levels among Indonesian women with gynecological cancer undergoing chemotherapy.Methods:This pilot st... Objective:This study aimed to determine the effect of the relaxation breathing exercise(RBE)on fatigue and cortisol levels among Indonesian women with gynecological cancer undergoing chemotherapy.Methods:This pilot study consecutively recruited 44 gynecological cancer patients to receive RBE(22)or usual care(22).Cortisol level was measured before and after completion of the intervention(day 8).Fatigue was measured using the Piper Fatigue Scale(PFS).Anxiety and depression were assessed using the Hospital Anxiety and Depression Scale(HADS)at the baseline days of the study for days 1,4,and 8.The obtained data were analyzed using Fisher’s exact test,the independent t-test,and the Mann-Whitney U test.Results:There were significant increases in cortisol levels within the groups,either the intervention or control groups,respectively(P-value=0.0003 and 0.001).Despite there being no statistical significance between the intervention and control groups,there were noticeable differences in the cortisol levels,indicating the extreme increase in cortisol levels in the control group(Median[IQR1-IQR3]:2.30[0.99-9.09];Min-Max:0.43-23.38)compared with the intervention group(Median[IQR1-IQR3]=2.97[1.26-5.18];Min-Max=0.39-6.91).Conclusions:RBE helps prevent a significant increase in cortisol levels that can alleviate fatigue for women with gynecological cancer.Further research was recommended to compare several intervention modalities for fatigue and cancer-related symptom management based on cortisol level changes. 展开更多
关键词 ANXIETY CORTISOL FATIGUE gynecological cancer relaxation breathing exercise
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The Importance of Breathing Training in Folk Dance Teaching
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作者 Xiaowei Sun 《Journal of Contemporary Educational Research》 2024年第4期187-192,共6页
The importance of breathing training in dance teaching is reflected in the two aspects of enhancing the quality of dance movements and sublimating the connotation of dance movements.For example,high-quality breathing ... The importance of breathing training in dance teaching is reflected in the two aspects of enhancing the quality of dance movements and sublimating the connotation of dance movements.For example,high-quality breathing can help performers complete the dance movements and improve the coordination of the movements;at the same time,the unique body rhythm formed by breathing can strengthen the visual effect of the performance and convey its spirit and soul to the audience.This requires folk dance teachers to carry out relevant training and teaching activities based on the categories and skills of dance breathing,such as changing students’ideological cognition,developing periodic breathing training courses,providing personalized guidance to students,and allowing students to adjust their learning and practice methods in the evaluation. 展开更多
关键词 Folk dance teaching breathing training IMPORTANCE Training methods
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Benefits of Radiotherapy with Indigenous Tools Aiding Deep Inspiration Breath Holding Technique Compared to Free Breathing Technique among Breast Cancer Patients in Bangladesh
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作者 Md. Arifur Rahman Rajesh Balakrishnan +1 位作者 Md. Salim Reza Qamruzzaman Chowdhury 《Advances in Breast Cancer Research》 2021年第3期75-86,共12页
<strong>Background:</strong><span style="font-family:Verdana;"> Post-operative breast radiotherapy is used to reduce recurrence</span><span style="font-family:"">... <strong>Background:</strong><span style="font-family:Verdana;"> Post-operative breast radiotherapy is used to reduce recurrence</span><span style="font-family:""><span style="font-family:Verdana;">. </span><span style="font-family:Verdana;">The aim of this study was</span><span style="font-family:Verdana;"> to investigate the outcomes of </span><span style="font-family:Verdana;">Deep</span><span style="font-family:Verdana;"> Inspiration Breath-Hold (DIBH) technique with indigenous </span><span style="font-family:Verdana;">breath holding</span><span style="font-family:Verdana;"> indicator scale in 3DCRT for breast cancer radiotherapy over </span><span style="font-family:Verdana;">Free</span><span style="font-family:Verdana;"> Breathing (FB) technique. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> An observational study </span><span style="font-family:Verdana;">conducted</span> </span><span style="font-family:""><span style="font-family:Verdana;">at the </span><span style="font-family:Verdana;">Department</span><span style="font-family:Verdana;"> of Radiation Oncology </span></span><span style="font-family:""><span style="font-family:Verdana;">at </span><span style="font-family:Verdana;">National</span><span style="font-family:Verdana;"> Institute of Cancer Research and Hospital, Dhaka and Square Hospital Limited, Dhaka, Bangladesh from June 2015 to May 2016. A total of 60</span></span><span style="font-family:""><span style="font-family:Verdana;"> confirmed breast cancer patients who underwent adjuvant radiotherapy were included. An indigenous reproducible plastic tool (Perspex) was used as </span><span style="font-family:Verdana;">breath holding</span><span style="font-family:Verdana;"> indicator scale with </span></span><span style="font-family:Verdana;">DIBH</span><span style="font-family:""><span style="font-family:Verdana;"> technique in 3DCRT</span><i><span style="font-family:Verdana;">. </span></i><span><span style="font-family:Verdana;">Paired sample t-test was used to compare with </span><span style="font-family:Verdana;">FB</span><span style="font-family:Verdana;"> technique. </span><b><span style="font-family:Verdana;">Results:</span></b><i> </i><span style="font-family:Verdana;">The mean age of patients </span><span style="font-family:Verdana;">w</span></span></span><span style="font-family:Verdana;">as</span><span style="font-family:Verdana;"> 47.32 (SD ± 8.33) years.</span><span style="font-family:""><span style="font-family:Verdana;"> In </span><span style="font-family:Verdana;">FB</span><span style="font-family:Verdana;"> technique, Mean Heart Dose (MHD) was 413.27 cGy while in </span><span style="font-family:Verdana;">DIBH</span><span style="font-family:Verdana;"> technique, it was 254.91 cGy (P < 0.001). The mean heart V20</span></span><span style="font-family:Verdana;"> and </span><span style="font-family:""><span style="font-family:Verdana;">V30 </span><span style="font-family:Verdana;">were</span><span style="font-family:Verdana;"> 5.5%, 4.37%</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">in FB and</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">3.13%, 2.36% in DIBH respectively. In </span><span style="font-family:Verdana;">FB</span><span style="font-family:Verdana;"> technique LADMD, LAD</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">0.2</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">cm</span><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;">, ILMD </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> ILV20 </span><span style="font-family:Verdana;">w</span></span><span style="font-family:Verdana;">ere</span><span style="font-family:Verdana;"> 1698.17</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">cGy, 2852.53 cGy, 1155.31 cGy </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> 28.62% while in </span><span style="font-family:Verdana;">DIBH</span><span style="font-family:Verdana;"> technique, it was reduced to 1164.01 cGy, 2132.24 cGy, 1007.98 cGy and 23.39% respectively. Similarly, the lung-CLMD and breast-CLMD </span><span style="font-family:Verdana;">w</span></span><span style="font-family:Verdana;">ere</span><span style="font-family:""><span style="font-family:Verdana;"> reduced from 38.37 cGy and 55.18 cGy to 24.64 cGy and 33.82 cGy respectively (P < 0.001). The mean difference for breast-CLMD was 21.36 cGy. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> The use of indigenous </span><span style="font-family:Verdana;">breath holding</span><span style="font-family:Verdana;"> indicator scale with DIBH had better outcomes on breast cancer radiotherapy.</span></span> 展开更多
关键词 BREAST-CANCER RADIOTHERAPY DIBH breath Holding Indicator Scale
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An Air-Breathing Micro Direct Methanol Fuel Cell with 3D KOH-Etched Cathode Structure
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作者 姜英琪 王晓红 +1 位作者 钟凌燕 刘理天 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第3期478-481,共4页
A micro direct methanol fuel cell (μDMFC) using MEMS technology is reported. The prototype features a unique 3D air-breathing cathode structure fabricated using KOH etching and double-side lithography. The optimiza... A micro direct methanol fuel cell (μDMFC) using MEMS technology is reported. The prototype features a unique 3D air-breathing cathode structure fabricated using KOH etching and double-side lithography. The optimization of the MEMS fabrication process is analyzed. The experimental results show the prototype generates a maximum power density of 2.52mW/cm^2 at room temperature. This performance is better than the published resuits of other silicon-based passive μDMFCs. Moreover,it is comparable with that of our previous active μDMFCs which require an external pump, certificating the feasibility of this new configuration. 展开更多
关键词 μDMFC air breathing bulk etching MEMS micro power source
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Generation of breathing solitons in the propagation and interactions of Airy–Gaussian beams in a cubic–quintic nonlinear medium 被引量:5
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作者 Weijun Chen Ying Ju +2 位作者 Chunyang Liu Liankai Wang Keqing Lu 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第11期528-533,共6页
Using the split-step Fourier transform method, we numerically investigate the generation of breathing solitons in the propagation and interactions of Airy–Gaussian(AiG) beams in a cubic–quintic nonlinear medium in... Using the split-step Fourier transform method, we numerically investigate the generation of breathing solitons in the propagation and interactions of Airy–Gaussian(AiG) beams in a cubic–quintic nonlinear medium in one transverse dimension. We show that the propagation of single AiG beams can generate stable breathing solitons that do not accelerate within a certain initial power range. The propagation direction of these breathing solitons can be controlled by introducing a launch angle to the incident AiG beams. When two AiG beams accelerated in opposite directions interact with each other,different breathing solitons and soliton pairs are observed by adjusting the phase shift, the beam interval, the amplitudes,and the light field distribution of the initial AiG beams. 展开更多
关键词 cubic-quintic nonlinear medium Airy-Gaussian beams propagation and interactions breathing solitons
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Device-guided breathing exercises for the treatment of hypertension: An overview 被引量:2
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作者 Kornelis JJ van Hateren Gijs WD Landman +2 位作者 Susan JJ Logtenberg Henk JG Bilo Nanne Kleefstra 《World Journal of Cardiology》 CAS 2014年第5期277-282,共6页
The American Heart Association considers device-guided breathing as a reasonable treatment modality in their statement on non-pharmacological options for lowering blood pressure. This review discusses all randomized c... The American Heart Association considers device-guided breathing as a reasonable treatment modality in their statement on non-pharmacological options for lowering blood pressure. This review discusses all randomized controlled trials that have investigated the effects of device-guided breathing on blood pressure in patients with hypertension. Thirteen studies were included in this review. In total, 627 patients were in-cluded, of which 365 patients were allocated to device-guided breathing. Only 6 studies used acceptable control groups: listening to music, meditative relaxa-tion exercises, or a sham-device. Two sponsored trials showed beneficial effects of device-guided breathing, both used listening to music as a control group. The remaining 4 studies, which had no employees of the manufacturer listed as co-author, observed no benefi-cial effects on blood pressure. There is only 1 study that used a sham device as a control group. All other studies were to some extend methodologically flawed. Based on the studies with an acceptable methodologi-cal quality, there is no clear evidence supporting a short-term beneficial effect on blood pressure by using device-guided breathing. 展开更多
关键词 HYPERTENSION Device-guided breathing Review
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Sleep disordered breathing in interstitial lung disease: A review 被引量:2
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作者 Lauren K Troy Tamera J Corte 《World Journal of Clinical Cases》 SCIE 2014年第12期828-834,共7页
Patients with interstitial lung disease commonly exhibit abnormal sleep architecture and increased sleep fragmentation on polysomnography. Fatigue is a frequent complaint, and it is likely that poor sleep quality is a... Patients with interstitial lung disease commonly exhibit abnormal sleep architecture and increased sleep fragmentation on polysomnography. Fatigue is a frequent complaint, and it is likely that poor sleep quality is a significant contributor. A number of studies have shown that sleep disordered breathing is prevalent in this population, particularly in the idiopathic pulmonary fibrosis subgroup. The factors that predispose these patients to obstructive sleep apnoea are not well understood, however it is believed that reduced caudal traction on the upper airway can enhance collapsibility. Ventilatory control system instability may also be an important factor, particularly in those with increased chemo-responsiveness, and in hypoxic conditions. Transient, repetitive nocturnal oxygen desaturation is frequently observed in interstitial lung disease, both with and without associated obstructive apnoeas. There is increasing evidence that sleep-desaturation is associated with increased mortality, and may be important in the pathogenesis of pulmonary hypertension in this population. 展开更多
关键词 SLEEP DISORDERED breathing INTERSTITIAL lung disease Pulmonary fibrosis NOCTURNAL hypoxia OBSTRUCTIVE SLEEP APNOEA
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Explicit solution of the radial breathing mode frequency of single-wailed carbon nanotubes 被引量:5
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作者 Tienchong Chang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2007年第2期159-162,共4页
On the basis of a molecular mechanics model, an analytical solution of the radial breathing mode (RBM) frequency of single-walled carbon nanotubes (SWCNTs) is obtained. The effects of tube chirality and tube diame... On the basis of a molecular mechanics model, an analytical solution of the radial breathing mode (RBM) frequency of single-walled carbon nanotubes (SWCNTs) is obtained. The effects of tube chirality and tube diameter on the RBM frequency are investigated and good agreement between the present results and existing data is found. The present analytical formula indicates that the chirality and size dependent elastic properties are responsible for the effects of the chirality and small size on the RBM frequency of an SWCNT. 展开更多
关键词 Carbon nanotubes.Radial breathing mode . Molecular mechanics
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Sleep-disordered breathing is associated with depletion of circulating endothelial progenitor cells and elevation in pulmonary arterial pressure in patients with decompensated systolic heart failure 被引量:5
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作者 Han ZHANG Liu FENG +4 位作者 Qi-Lin WAN Yan HONG Yan-Ming LI Guan-Chang CHENG Xin-Qiang HAN 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2015年第4期424-430,共7页
Background Sleep-disordered breathing (SDB) is known to occur frequently in and may predict worsening progression of patients with congestive heart failure (CHF). SDB is also known to play an important role in the... Background Sleep-disordered breathing (SDB) is known to occur frequently in and may predict worsening progression of patients with congestive heart failure (CHF). SDB is also known to play an important role in the development of idiopathic pulmonary arterial hyper- tension (PAH) via inducing endothelial dysfunction and vascular remodeling, a pathological process that can be significantly influenced by factors such as osteoprotegerin (OPG) and endothelial progenitor cells (EPCs). The objective of this study is to determine if CHF with SDB is associated with changes in OPG, EPCs, and PAIl. Methods EPCs were isolated, cultured, and quantified from CHF patients with SDB (n = 52), or without SDB (n - 68). OPG and N-terminal pro-brain natriuretic peptide (NT-proBNP) from each group was analyzed and cor- related with EPCs and the mean pulmonary artery pressure (mPAP) measured by right heart catheterization. Results A significant decrease in circulating EPCs (29.30 ± 9.01 vs. 45.17 ± 10.51 EPCs/x 200 field; P 〈 0.05) was found in CHF patients with SDB compared to those without SDB. Both OPG (789.83 ±89.38 vs. 551.29 ± 42.12 pg/mL; P 〈 0.05) and NT-proBNP (5946.50 ± 1434.50 vs. 3028.60 ± 811.90 ng/mL; P 〈 0.05) were also significantly elevated in SDB CHF patients who also had significantly elevated mPAP (50.2 ± 9.5 vs. 36.4 ± 4.1 mm Hg; P 〈 0.05). EPC numbers correlated inversely with the episodes of apnea and hypopnea per hour (RDI, r = -0.45, P = 0.037) and blood level of OPG (r =-0.53, P = 0.011). Although NT-proBNP was also increased significantly in patients with SDB, it had no correlation with either EPCs or RD1. Conclusions SDBdue to hypoxemia from decompensated CHF is associated with (1) OPG elevation, (2) EPC depletion, and (3) mPAP elevation. The inverse relationship of circulating OPG with EPCs suggests a likely mechanism for hypoxemia and OPG in the development of pulmonary vascular dysfunction via depleting EPCs, thus worsening prognosis of CHF. 展开更多
关键词 Congestive heart failure Endothelial progenitor cells OSTEOPROTEGERIN Sleep-disordered breathing
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Exact breathing soliton solutions in combined time-dependent harmonic-lattice potential 被引量:1
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作者 佑六云 李画眉 何俊荣 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期153-158,共6页
We investigate the explicit novel localized nonlinear matter waves of the cubic-quintic nonlinear Schr6dinger equation with spafiotemporal modulation of the nonlinearities and the harmonic-lattice potential using a mo... We investigate the explicit novel localized nonlinear matter waves of the cubic-quintic nonlinear Schr6dinger equation with spafiotemporal modulation of the nonlinearities and the harmonic-lattice potential using a modified similarity trans- formation. We also find that when the modulus of the Jacobian elliptic function in the limit closes to 1, the shapes of the breathing solitons may exhibit some interesting features, i.e., one breathing soliton dividing into two in the ground state. The stability of the exact solutions is investigated numerically such that some stable breathing soliton solutions are found. 展开更多
关键词 breathing soliton cubic-quintic nonlinearity harmonic-lattice potential
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A semi-analytical approach for calculating the equilibrium structure and radial breathing mode frequency of single-walled carbon nanotubes 被引量:1
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作者 J.Gong L.Thompson G.Li 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第6期1075-1087,共13页
A semi-analytical model for determining the equilibrium configuration and the radial breathing mode (RBM) frequency of single-wall carbon nanotubes (CNTs) is presented. By taking advantage of the symmetry characterist... A semi-analytical model for determining the equilibrium configuration and the radial breathing mode (RBM) frequency of single-wall carbon nanotubes (CNTs) is presented. By taking advantage of the symmetry characteristics, a CNT structure is represented by five independent variables. A line search optimization procedure is employed to determine the equilibrium values of these variables by minimizing the potential energy. With the equilibrium configuration obtained, the semi-analytical model enables an efficient calculation of the RBM frequency of the CNTs. The radius and radial breathing mode frequency results obtained from the semi-analytical approach are compared with those from molecular dynamics (MD) and ab initio calculations. The results demonstrate that the semi-analytical approach offers an efficient and accurate way to determine the equilibrium structure and radial breathing mode frequency of CNTs. 展开更多
关键词 Carbon nanotubes Equilibrium structure Radial breathing mode frequency
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Nonlinear Dynamic Characteristics of a Simple Blade with Breathing Crack Using Ansys Software 被引量:2
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作者 Salwan Obeed Waheed Nawras Haidar Mostafa Dhyai Hassan Jawad 《World Journal of Mechanics》 2011年第2期21-30,共10页
Nonlinear dynamic response represents the most important studies for structures subjected to a dynamic mo-tion so that it provides the researcher by an excellent information especially at critical design levels. The u... Nonlinear dynamic response represents the most important studies for structures subjected to a dynamic mo-tion so that it provides the researcher by an excellent information especially at critical design levels. The un-predictable nonlinearity in the structure appears when damage is inherited. Most times, the failure of the structure is related to the dynamic nonlinearity. With regard to the breathing phenomena for nonlinear struc-tural systems, very little is known about how the nonlinearities influence the response and the dynamic char-acteristics of cracked structures. In this research, dynamic nonlinearity is presented in damaged structure due to presence of a crack. The crack is assumed to be open and close simultaneously and then breathing. Effect of breathing phenomenon was studied deeply. Crack breathing is simulated at the crack surfaces using con-tact elements. The contact, geometrical, penalty, and spin stiffnesses are taken in consideration. In addition, effect of several important parameters such as rotor angular velocity and crack ratio are studied. The study showed that the breathing natural frequency of any structure is ranged between opened (no contact) and closed crack natural frequencies. The larger crack length, the more nonlinear disturbance in the dynamic re-sponse behavior. Also, at a critical crack length, some mode shapes tend to exchange and pass over with other modes. The presence of the mode interchanging and mode crossover was a guide on the nonlinear re-sponse for the cracked structure. The numerical modeling is achieved using ANSYS finite element program. Experimental data are used for validating the accurate use of contact elements in ANSYS environment. 展开更多
关键词 Nonlinear DYNAMICS breathing PHENOMENA Cracked BLADE CONTACT ANSYS
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The effect of slow deep breathing relaxation exercise on pain levels during and post chest tube removal after coronary artery bypass graft surgery 被引量:3
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作者 Mohamad I.Jarrah Issa M.Hweidi +5 位作者 Sirin A.Al-Dolat Hossam N.Alhawatmeh Salwa M.Al-Obeisat Lama I.Hweidi Aysam I.Hweidi Osama A.Alkouri 《International Journal of Nursing Sciences》 CSCD 2022年第2期155-161,I0003,共8页
Objectives:This study aimed to evaluate the effectiveness of slow deep breathing relaxation exercise(SDBRE)in reducing patients’pain levels during chest tube removal(CTR)post coronary artery bypass grafting(CABG)surg... Objectives:This study aimed to evaluate the effectiveness of slow deep breathing relaxation exercise(SDBRE)in reducing patients’pain levels during chest tube removal(CTR)post coronary artery bypass grafting(CABG)surgery.Methods:In 2019,fifty post-CABG patients were conveniently selected from a cardiac intensive care unit in Jordan’s major referral heart institute.The patients were randomly assigned to either an intervention group or a control group.A total of 25 patients were assigned into the experimental group who received slow deep breathing relaxation Exercise(SDBRE)alongside the conventional care before CTR.The remaining 25 patients constituted the control group(50%)that had CTR following conventional care.The Visual Analogue Scale(VAS)was used to measure the participants’pain levels during three phases:before CTR(Time 1),5-min post CTR(Time 2),and 15-min post CTR(Time 2)to compare the intervention effect between the two groups.Results:The data analysis findings for the control and intervention group of patients showed that there was a statistically significant decline in their pain level across time for both groups(H¼32.71,P<0.01;H=47.23,P<0.01)respectively.The intervention group had significantly lower pain levels than the control group at Time 2(3.50[1.20,5.30]vs.7.90[7.00,9.00],P<0.01)and Time 3(0.00[0.00,1.30]vs.3.60[2.40,4.10]P<0.01).Conclusions:Using SDBRE during CTR is an effective technique for reducing pain which can minimize the need for analgesics and their associated adverse effects. 展开更多
关键词 breathing exercises Chest tubes removal Coronary artery bypass grafting PAIN Patients JORDAN
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Propagation dynamics of dipole breathing wave in lossy nonlocal nonlinear media 被引量:1
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作者 Jian-Li Guo Zhen-Jun Yang +1 位作者 Xing-Liang Li Shu-Min Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第1期273-280,共8页
In the framework of nonlinear wave optics,we report the evolution process of a dipole breathing wave in lossy nonlocal nonlinear media based on the nonlocal nonlinear Schrödinger equation.The analytical expressio... In the framework of nonlinear wave optics,we report the evolution process of a dipole breathing wave in lossy nonlocal nonlinear media based on the nonlocal nonlinear Schrödinger equation.The analytical expression of the dipole breathing wave in such a nonlinear system is obtained by using the variational method.Taking advantage of the analytical expression,we analyze the influences of various physical parameters on the breathing wave propagation,including the propagation loss and the input power on the beam width,the beam intensity,and the wavefront curvature.Also,the corresponding analytical solutions are obtained.The validity of the analysis results is verified by numerical simulation.This study provides some new insights for investigating beam propagation in lossy nonlinear media. 展开更多
关键词 breathing wave PROPAGATION variational method
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Cell Breathing Scheme for Mega-Constellation Satellite Networks 被引量:1
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作者 LIN Zitong LI Hewu LIU Jun 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2022年第2期152-163,共12页
Low earth orbit(LEO)mega-constellations can provide global low-latency high bandwidth coverage compared to the terrestrial network.The time-varying topology of satellite networks and the uneven traffic distribution le... Low earth orbit(LEO)mega-constellations can provide global low-latency high bandwidth coverage compared to the terrestrial network.The time-varying topology of satellite networks and the uneven traffic distribution lead to the mismatch between satellites and users,resulting in the waste of satellite resources and the degradation of user performance.Through negotiation with neighbors,the traditional terrestrial cell breathing continuously converges to the optimal cell size in the face of user tides,but this method is difficult to converge timely when facing rapid and extreme flow changes caused by the rapid movement of satellites.This paper presents a fast adaptive cell breathing scheme(Fa B)through sub-block division and satellite cell initialization and adjustment.Fa B divides the ground into sub-blocks according to the user density.When the satellite moves in the same sub-block,the step size of breathing is adjusted according to the cell size difference between the previous satellite and the current satellite.When the satellite switches between different sub-blocks,the initial value of the cell is determined according to the density of the new sub-block.In addition to negotiating with neighboring satellites,this scheme also introduces location information to directly adjust the parameters of cell breathing and decrease the time of cell breathing convergence.From the real constellation data-driven simulation,we conclude that Fa B can quickly adjust the size of the cell with the location changing,and the utilization rate is increased by 2.66 times compared to the method with no cell breathing,and by2.37 times compared to the method with cell breathing without location information. 展开更多
关键词 satellite networks cell breathing mega-constellation block division
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Effectiveness of Relaxation Breathing Exercise on fatigue in gynecological cancer patients undergoing chemotherapy 被引量:1
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作者 Mulhaeriah Yati Afiyanti +1 位作者 Engkus Kusdinar Achmad Moh Syafar Sangkala 《International Journal of Nursing Sciences》 2018年第4期331-335,共5页
Purpose:This study aimed to determine the effectiveness of Relaxation Breathing Exercise(RBE)on fatigue in patients with gynaecological cancer undergoing chemotherapy.Methods:We used a quasi-experiment with pre-and po... Purpose:This study aimed to determine the effectiveness of Relaxation Breathing Exercise(RBE)on fatigue in patients with gynaecological cancer undergoing chemotherapy.Methods:We used a quasi-experiment with pre-and post-test design.Forty-two patients were consecutively sampled,21 of whom were assigned to the group receiving RBE four times a day and 21 to the group receiving RBE twice a day.Fatigue scores were measured every day for 7 days for both groups using the Piper Fatigue Scale.Data obtained were analysed using repeated-ANOVA and independent ttest with a significant level of a<0.01.Results:We found a significant decrease(P<0.01)in the mean fatigue scores of both groups(four times RBE in a day group=3.29±0.59 and twice RBE in a day group=4.19±0.61)after the completion of the intervention.However,the four times RBE a day group showed larger decrease on fatigue scores than the twice RBE a day group did(Mean Difference=0.91;99%CI=0.41 to 1.41;P=0.001).Conclusion:Conducting RBE four times a day effectively alleviated fatigue better than RBE twice a day on gynaecological cancer patients undergoing chemotherapy. 展开更多
关键词 Relaxation breathing exercise Gynaecologic cancer CHEMOTHERAPY FATIGUE
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