scholarly journals Simulation of HVAC Local Control Based on Occupants Locations and Preferences

Author(s):  
Zheng Liu ◽  
Shide Salimi ◽  
Amin Hammad
Keyword(s):  
Author(s):  
W.G. Wier

A fundamentally new understanding of cardiac excitation-contraction (E-C) coupling is being developed from recent experimental work using confocal microscopy of single isolated heart cells. In particular, the transient change in intracellular free calcium ion concentration ([Ca2+]i transient) that activates muscle contraction is now viewed as resulting from the spatial and temporal summation of small (∼ 8 μm3), subcellular, stereotyped ‘local [Ca2+]i-transients' or, as they have been called, ‘calcium sparks'. This new understanding may be called ‘local control of E-C coupling'. The relevance to normal heart cell function of ‘local control, theory and the recent confocal data on spontaneous Ca2+ ‘sparks', and on electrically evoked local [Ca2+]i-transients has been unknown however, because the previous studies were all conducted on slack, internally perfused, single, enzymatically dissociated cardiac cells, at room temperature, usually with Cs+ replacing K+, and often in the presence of Ca2-channel blockers. The present work was undertaken to establish whether or not the concepts derived from these studies are in fact relevant to normal cardiac tissue under physiological conditions, by attempting to record local [Ca2+]i-transients, sparks (and Ca2+ waves) in intact, multi-cellular cardiac tissue.


2004 ◽  
Vol 171 (4S) ◽  
pp. 385-385 ◽  
Author(s):  
Carl K. Gjertson ◽  
Kevin P. Asher ◽  
Joshua D. Sclar ◽  
Aaron E. Katz ◽  
Erik T. Goluboff ◽  
...  

2020 ◽  
pp. 1-10
Author(s):  
Dhiego C. A. Bastos ◽  
Rafael A. Vega ◽  
Jeffrey I. Traylor ◽  
Amol J. Ghia ◽  
Jing Li ◽  
...  

OBJECTIVEThe objective of this study was to present the results of a consecutive series of 120 cases treated with spinal laser interstitial thermal therapy (sLITT) to manage epidural spinal cord compression (ESCC) from metastatic tumors.METHODSThe electronic records of patients treated from 2013 to 2019 were analyzed retrospectively. Data collected included demographic, pathology, clinical, operative, and imaging findings; degree of epidural compression before and after sLITT; length of hospital stay; complications; and duration before subsequent oncological treatment. Independent-sample t-tests were used to compare means between pre- and post-sLITT treatments. Survival was estimated by the Kaplan-Meier method. Multivariate logistic regression was used to analyze predictive factors for local recurrence and neurological complications.RESULTSThere were 110 patients who underwent 120 sLITT procedures. Spinal levels treated included 5 cervical, 8 lumbar, and 107 thoracic. The pre-sLITT Frankel grades were E (91.7%), D (6.7%), and C (1.7%). The preoperative ESCC grade was 1c or higher in 92% of cases. Metastases were most common from renal cell carcinoma (39%), followed by non–small cell lung carcinoma (10.8%) and other tumors (35%). The most common location of ESCC was in the vertebral body (88.3%), followed by paraspinal/foraminal (7.5%) and posterior elements (4.2%). Adjuvant radiotherapy (spinal stereotactic radiosurgery or conventional external beam radiation therapy) was performed in 87 cases (72.5%), whereas 33 procedures (27.5%) were performed as salvage after radiotherapy options were exhausted. sLITT was performed without need for spinal stabilization in 87 cases (72.5%). Post-sLITT Frankel grades were E (85%), D (10%), C (4.2%), and B (0.8%); treatment was associated with a median decrease of 2 ESCC grades. The local control rate at 1 year was 81.7%. Local control failure occurred in 25 cases (20.8%). The median progression-free survival was not reached, and overall survival was 14 months. Tumor location in the paraspinal region and salvage treatment were independent predictors of local recurrence, with hazard ratios of 6.3 and 3.3, respectively (p = 0.01). Complications were observed in 22 cases (18.3%). sLITT procedures performed in the lumbar and cervical spine had hazard ratios for neurological complications of 15.4 and 17.1 (p < 0.01), respectively, relative to the thoracic spine.CONCLUSIONSsLITT is safe and provides effective local control for high-grade ESCC from vertebral metastases in the thoracic spine, particularly when combined with adjuvant radiotherapy. The authors propose considering sLITT as an alternative to open surgery in selected patients with spinal metastases.


2007 ◽  
Vol 23 (2) ◽  
pp. 87 ◽  
Author(s):  
Ki-Jae Park ◽  
Hong-Jo Choi ◽  
Young-Hoon Roh ◽  
Jong-Sok Shin ◽  
Hyung-Sik Lee

2018 ◽  
Vol 64 (5) ◽  
pp. 645-650
Author(s):  
Olga Kravets ◽  
Yelena Romanova ◽  
Oleg Kozlov ◽  
Mikhail Nechushkin ◽  
A. Gavrilova ◽  
...  

We present our results of 3D CT/MRI brachytherapy (BT) planning in 115 patients with locally advanced cervical cancer T2b-3bN0-1M0. The aim of this study was to assess the differences in the visualization of tumor target volumes and risk organs during the 3D CT/MRI BT. The results of the study revealed that the use of MRI imaging for dosimetric planning of dose distribution for a given volume of a cervical tumor target was the best method of visualization of the soft tissue component of the tumor process in comparison with CT images, it allowed to differentially visualize the cervix and uterine body, directly the tumor volume. Mean D90 HR-CTV for MRI was 32.9 cm3 versus 45.9 cm3 for CT at the time of first BT, p = 0.0002, which is important for local control of the tumor process. The contouring of the organs of risk (bladder and rectum) through MRI images allows for more clearly visualizing the contours, which statistically significantly reduces the dose load for individual dosimetric planning in the D2cc control volume, і.є. the minimum dose of 2 cm3 of the organ of risk: D2cc for the bladder was 24.3 Gy for MRI versus 34.8 Gy on CT (p = 0.045); D2cc for the rectum - 18.7 Gy for MRI versus 26.8 Gy for CT (p = 0.046). This is a prognostically important stage in promising local control, which allows preventing manifestation of radiation damage.


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