Journal articles: 'HDRB'

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Cancellara, Donato, Fabio de Angelis, and Mario Pasquino. "Influence of the Strain Hardening of HDRBs in the Evaluation of the Seismic Response of a RC Base Isolated Structure." Advanced Materials Research 602-604 (December 2012): 1546–54. http://dx.doi.org/10.4028/www.scientific.net/amr.602-604.1546.

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In this paper we have analyzed the influence of the strain hardening behavior of High Damping Rubber Bearings (HDRBs) adopted for a base isolation system of a Reinforced Concrete (RC) isolated structure. For the modeling of the rubber isolators we have adopted an evolution of the Bouc-Wen’s hysteretic model taking into account the incremental hardening effect which appears when the shear strain of the HDRB exceeds the limit value around 100% usually adopted in design practice. The incremental hardening effect is sometimes neglected in the design but it is an important aspect because it ensures a seismic protection of the base isolated structure also in presence of exceptional seismic events for intensity or frequency content. In this paper we have highlighted the significant influence of this phenomenon in the seismic response of the isolated structure by reporting the cyclic behavior of a HDRB respectively neglecting and considering this aspect.

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Islam, A. B. M. Saiful. "DIMINISHING SEISMIC EFFECT ON BUILDINGS USING BEARING ISOLATION." IIUM Engineering Journal 19, no. 1 (June 1, 2018): 59–71. http://dx.doi.org/10.31436/iiumej.v19i1.844.

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Adopting suitable seismic protection techniques is presently a foremost concern worldwide and has become a governing principle in the growing construction industry globally. Thus, a rapid upsurge in infrastructure development in seismic-prone areas requires proper treatment for building structures. Therefore, the aim of the study is to incorporate a rubber bearing isolation device in a building base in order to diminish the seismic effect on the superstructure. The changes of structural parameters and responses of fixed-based buildings for applying High Damping Rubber Bearing (HDRB) are investigated under site-specific ground excitation. Twenty representative buildings have been used to examine the responses employing four types of HDRB systems. The study reveals that the HDRB makes the structure more flexible, offering reduced structural responses. The introduction of HDRB may help to decrease floor moment by 31~55%, which can allow the structures to withstand comparatively high seismic tremors safely and efficiently. The base isolated structures experience significant lateral shift between 87.15 and 130.15 mm, and relative floor displacement is below 3% because of additional flexibility. The effective inertia height for the BI buildings remains under two-thirds of building elevation showing triangular distribution concentrating to the top story level. The reduction in forces, moments, and relative displacements of the structural members by applying HDRB can ensure economic design and higher structural safety against seismic excitation. ABSTRAK: Penerapan teknik yang sesuai bagi pelindungan gelombang seismos menjadi penekanan semasa di seluruh dunia dan telah menjadi prinsip penentu dalam industri pembinaan secara global. Oleh itu, kenaikan yang cepat dalam pembangunan infrastuktur dalam kawasan terdedah kepada gelombang seismos memerlukan penyelenggaraan yang betul bagi struktur bangunan. Jadi, matlamat kajian ini adalah bagi menggabungkan getah alat pengandar asing dalam teras bangunan bagi mengurangkan kesan seismos pada struktur asas. Perubahan pada parameter struktur dan tindak balas tapak-tetap bangunan bagi penggunaan teknik High Damping Rubber Bearing (HDRB) dikaji di bawah setiap kenaikan getaran gelombang sebenar bawah tanah. Dua puluh bangunan telah digunakan bagi menilai tindak balas terhadap penggunaan empat jenis sistem HDRB. Kajian menunjukkan HDRB membuatkan struktur lebih fleksibel, dan mengurangkan tindak balas terhadap struktur. Penggunaan HDRB dalam pembangunan membantu mengurangkan momen lantai sebanyak 31~55%, di mana struktur bangunan lebih tahan terhadap gegaran tinggi secara selamat dan berkesan. Struktur asas yang terasing mengalami peralihan sisi yang ketara antara 87.15 dan 130.15 mm, dan anjakan lantai relatif di bawah 3% dengan penambahan sistem fleksibel ini. Ketinggian inertia berkesan bagi bangunan BI kekal di antara dua pertiga ketinggian bangunan. Ini menunjukkan pengagihan segitiga tertumpu pada aras atas bangunan. Pengurangan pada daya, momen dan perubahan relatif struktur menggunakan HDRB dapat memastikan reka bentuk lebih ekonomi dan selamat pada bangunan tinggi daripada sebarang gelombang seismos.

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Braga, Franco, Marco Faggella, Rosario Gigliotti, and Michelangelo Laterza. "Nonlinear Dynamic Response of HDRB and Hybrid HDRB-Friction Sliders Base Isolation Systems." Bulletin of Earthquake Engineering 3, no. 3 (December 2005): 333–53. http://dx.doi.org/10.1007/s10518-005-1242-2.

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Maia, M. A., P. Novaes, A. C. Pellizzon, and R. Ferrigno. "High dose rate post-operative brachytherapy and external beam radiotherapy for uterine sarcomas." Journal of Clinical Oncology 24, no. 18_suppl (June 20, 2006): 15027. http://dx.doi.org/10.1200/jco.2006.24.18_suppl.15027.

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15027 Background: Uteine sarcoma (US) generally needs an aggressive approach with surgical cytoreduction at the time of initial diagnosis with maximum debulking of tumor. This offers the possibility of prolonged survival or cure. The need for adjuvant radiotherapy is not well established for US. Methods: 25 patients presenting completely ressected US were treated from November, 1992 to June, 2003. All the patients had a multidisciplinary approach with surgery, external beam radiation therapy (EBRT) given in a four- fields “box” technique, and high dose rate brachytherapy (HDRB), using either colpostats or vaginal cylinders with diameters ranging from 2.5 to 4 cm. The entire vaginal length treated with HDRB was 2 cm in all cases. Results: The median age of patients was 62 years (range 39–84). The EBRT dose prescription ranged from 40 Gy to 50,4 Gy (median 48 Gy). HDRB was given concurrent to EBRT in 14 patients (56%). The HDRB for the remaining patients started in median interval of 34 days (range 5–99 days) after the completion of EBRT. The median BED for hole treatment was 91.5 Gy10 (range 85.6 Gy10–97.9 Gy10), with a standard deviation of 3.7. The 10- year actuarial disease free and overall survivals were and 42.2% and 63.4%, respectively. On univariate analysis predictive factors for disease free survival (DFS) were age at initial presentation (p = 0.0268), parity (p = 0.0441), tumor grade (p = 0.0095), cervical or vaginal invasion (p = 0.0014) and node dissection at time of surgery (p = 0.0471). On multivariate analysis the only predictive factor was cervical or vaginal invasion (p = 0.048), hazard ratio of 4.7. Conclusion: Our small and heterogeneous group of patients analyzed precludes any definitive conclusions regarding the impact of HDRB combined to EBRT on recurrence or survival of the patients. As US are aggressive tumors, it is quite likely that neither radiotherapy nor chemotherapy alone will appreciably improve survival. If we assume that adjuvant radiation therapy provides better locoregional tumor control, hematogenous metastases probably will assume an even greater proportion of treatment failures. No significant financial relationships to disclose.

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Kragelj, Borut. "Obstructive urination problems after high-dose-rate brachytherapy boost treatment for prostate cancer are avoidable." Radiology and Oncology 50, no. 1 (February 16, 2016): 94–103. http://dx.doi.org/10.1515/raon-2015-0010.

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AbstractBackgroundAiming at improving treatment individualization in patients with prostate cancer treated with combination of external beam radiotherapy and high-dose-rate brachytherapy to boost the dose to prostate (HDRB-B), the objective was to evaluate factors that have potential impact on obstructive urination problems (OUP) after HDRB-B.Patients and methodsIn the follow-up study 88 patients consecutively treated with HDRB-B at the Institute of Oncology Ljubljana in the period 2006-2011 were included. The observed outcome was deterioration of OUP (DOUP) during the follow-up period longer than 1 year. Univariate and multivariate relationship analysis between DOUP and potential risk factors (treatment factors, patients’ characteristics) was carried out by using binary logistic regression. ROC curve was constructed on predicted values and the area under the curve (AUC) calculated to assess the performance of the multivariate model.ResultsAnalysis was carried out on 71 patients who completed 3 years of follow-up. DOUP was noted in 13/71 (18.3%) of them. The results of multivariate analysis showed statistically significant relationship between DOUP and anti-coagulation treatment (OR 4.86, 95% C.I. limits: 1.21-19.61, p = 0.026). Also minimal dose received by 90% of the urethra volume was close to statistical significance (OR = 1.23; 95% C.I. limits: 0.98-1.07, p = 0.099). The value of AUC was 0.755.ConclusionsThe study emphasized the relationship between DOUP and anticoagulation treatment, and suggested the multivariate model with fair predictive performance. This model potentially enables a reduction of DOUP after HDRB-B. It supports the belief that further research should be focused on urethral sphincter as a critical structure for OUP.

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Cury, F. L., M. Duclos, A. G. Aprikian, H. Patrocinio, W. Kassouf, G. Shenouda, S. Faria, M. David, and L. Souhami. "Single fraction high-dose-rate brachytherapy and hypofractionated external beam radiation therapy in the treatment of intermediate-risk prostate cancer: Long-term results." Journal of Clinical Oncology 29, no. 7_suppl (March 1, 2011): 83. http://dx.doi.org/10.1200/jco.2011.29.7_suppl.83.

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83 Background: We present the long-term results of a cohort of patients with intermediate-risk prostate cancer (PC) treated with single fraction high-dose-rate brachytherapy (HDRB) combined with hypofractionated external beam radiation therapy (HRT). Methods: Patients with intermediate-risk PC were treated exclusively with HDRB and HRT. HDRB delivered a dose of 10 Gy to the prostate gland and HRT consisted of 50 Gy delivered in 20 daily fractions. The planning target volume was the prostate gland with a 1 cm margin all around. The first 121 consecutive patients with a minimum of 2 years post-treatment follow-up were assessed for acute and chronic toxicity and disease control. Results: The median follow-up was 62.8 months. No acute grade III or higher toxicities were seen. Grade II late GI toxicity was seen in 9 patients (7.4%) and grade III in 2 (1.6%). Grade 3 GU toxicity was seen in 2 patients (1.6%), both with urinary obstructive symptoms requiring catheterization. A repeat biopsy was offered to the first 58 consecutively treated patients, and 44 patients agreed with the procedure. A negative biopsy was found in 40 patients (91%). The biochemical relapse-free survival rate at 5 and 8 years were 90.7% and 81.4%, with 13 patients presenting biochemical failure. Among them, nine were diagnosed with distant metastasis. Prostate cancer-specific and overall survival rates at 8 years were 100% and 95.5%, respectively. Conclusions: Our program of HDRB and HRT is well tolerated, with acceptable toxicity rates. Furthermore, results from re-biopsies revealed an elevated rate of local control. These results are encouraging and confirm that the use of conformal RT techniques, adapted to specific biological features, have the potential to improve the therapeutic ratio in intermediate risk PC patients. No significant financial relationships to disclose.

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Markou, Athanasios A., and George D. Manolis. "Energy and Transmissibility in Nonlinear Viscous Base Isolators." Journal of Theoretical and Applied Mechanics 46, no. 3 (September 1, 2016): 17–34. http://dx.doi.org/10.1515/jtam-2016-0014.

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Abstract High damping rubber bearings (HDRB) are the most commonly used base isolators in buildings and are often combined with other systems, such as sliding bearings. Their mechanical behaviour is highly nonlinear and dependent on a number of factors. At first, a physical process is suggested here to explain the empirical formula introduced by J.M. Kelly in 1991, where the dissipated energy of a HDRB under cyclic testing, at constant frequency, is proportional to the amplitude of the shear strain, raised to a power of approximately 1.50. This physical process is best described by non-Newtonian fluid behaviour, originally developed by F.H. Norton in 1929 to describe creep in steel at high-temperatures. The constitutive model used includes a viscous term, that depends on the absolute value of the velocity, raised to a non-integer power. The identification of a three parameter Kelvin model, the simplest possible system with nonlinear viscosity, is also suggested here. Furthermore, a more advanced model with variable damping coefficient is implemented to better model in this complex mechanical process. Next, the assumption of strain-rate dependence in their rubber layers under cyclic loading is examined in order to best interpret experimental results on the transmission of motion between the upper and lower surfaces of HDRB. More specifically, the stress-relaxation phenomenon observed with time in HRDB can be reproduced numerically, only if the constitutive model includes a viscous term, that depends on the absolute value of the velocity raised to a non-integer power, i. e., the Norton fluid previously mentioned. Thus, it becomes possible to compute the displacement transmissibility function between the top and bottom surfaces of HDRB base isolator systems and to draw engineering-type conclusions, relevant to their design under time-harmonic loads.

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Ehrenfeld, Nicole, Gloria J. Levicán, and Pilar Parada. "Heterodisulfide Reductase from Acidithiobacilli is a Key Component Involved in Metabolism of Reduced Inorganic Sulfur Compounds." Advanced Materials Research 825 (October 2013): 194–97. http://dx.doi.org/10.4028/www.scientific.net/amr.825.194.

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Heterodisulfide reductase (Hdr), is an iron-sulfur protein which in anaerobic methanogenic archaea catalyzes the reduction of the disulphide bond between coenzyme M and coenzyme B and is coupled to methane formation. In aerobic acidophilic chemolithotrophic bacteria (e.g., biomining bacteria) the function of this enzyme is unclear. Inspection of the genomic sequences of Acidithiobacillus ferrooxidans DSM 16786 and Acidithiobacillus thiooxidans DSM 17318 and reverse transcriptase-PCR results revealed a cluster of six co-transcribed genes, hdrC1, hdrB1, hdrA, orf1, hdrC2 and hdrB2, encoding proteins with high similarity to catalytic Hdr subunits. Additionally, microarray expression profiling and quantitative RT-PCR experiments demonstrated that the hdr genes of A.ferrooxidans and A. thiooxidans were highly expressed when bacteria are grown in the presence of sulfur and tetrathionate. Moreover, hdr genes in A. ferrooxidans were greatly up-regulated when this microorganism was grown in sulfur compared to ferrous medium. These results strongly support a role for Hdr in oxidative metabolism of reduced sulfur compounds in aerobic chemolithotrophic bacteria.

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Vatanshenas, Ali, Takahiro Mori, and Nobuo Murota. "Structural rehabilitation using high damping rubber bearing (HDRB)." Bulletin of the New Zealand Society for Earthquake Engineering 54, no. 1 (March 1, 2021): 49–57. http://dx.doi.org/10.5459/bnzsee.54.1.49-57.

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High damping rubber bearings show highly nonlinear stress-strain behaviour. Deformation-history integral (DHI) model which can estimate small strain stiffness degradation and nonlinear plasticity via a relatively simple innovative formulation is implemented in this study to model HDRB as the rehabilitation method for a seismically vulnerable building. Considered structure in this study is a three-dimensional, four-story steel frame residential building with a concentrically braced system. Nonlinear direct integration time history analysis and plastic hinges approach were implemented to evaluate structural behaviour of considered structure. It was observed that structural responses enhanced significantly after rehabilitation. Absolute maximum base shear values decreased 61.8% and 92.2% in the worst and best cases, respectively. Most of structural elements remained elastic after rehabilitation and required performance level was satisfied.

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Clemente, Paolo, Giovanni Bongiovanni, Giacomo Buffarini, Fernando Saitta, Maria Gabriella Castellano, and Federico Scafati. "Effectiveness of HDRB isolation systems under low energy earthquakes." Soil Dynamics and Earthquake Engineering 118 (March 2019): 207–20. http://dx.doi.org/10.1016/j.soildyn.2018.12.018.

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Fauzan, Afdhalul Ihsan, Mutia Putri Monika, and Zev Al Jauhari. "The effect of seismic base isolation on structural response of a 12-story hotel building in Padang, Indonesia." E3S Web of Conferences 156 (2020): 05026. http://dx.doi.org/10.1051/e3sconf/202015605026.

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The amount of potential investment in Padang City, Indonesia since 2017 attracted many investors to contribute to the city. One of the investments is a 12-story hotel that will be constructed in By Pass Street of the city. The hotel is located in a high seismic zone area, so the seismic base isolation has been proposed to be used in the hotel building. The main aim of using a seismic base isolation device is to reduce the inertia forces introduced in the structure due to earthquakes by shifting the fundamental period of the structure out of dangerous resonance range and concentration of the deformation demand at the isolation system. An analytical study on the Reinforced Concrete (RC) hotel building with and without rubber bearing (RB) base isolation is carried out using the response spectrum and time history analysis methods. The results show that internal forces and inter-story drift of the building with high damping rubber bearing (HDRB) are lower than that of the fixed base with a remarkable margin. From this study, it is recommended to use the HDRB base isolation for medium and high rise buildings with soft soil in Padang City, Indonesia.

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SONEJI, B. B., and R. S. JANGID. "EFFECTIVENESS OF SEISMIC ISOLATION FOR CABLE-STAYED BRIDGES." International Journal of Structural Stability and Dynamics 06, no. 01 (March 2006): 77–96. http://dx.doi.org/10.1142/s0219455406001836.

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This paper investigates the effectiveness of elastomeric and sliding types of isolation systems for the seismic response control of cable-stayed bridges. A simplified two-dimensional lumped-mass finite-element model of the Quincy Bay-view Bridge at Illinois was developed for the investigation. The seismic isolation of cable-stayed bridges is achieved using three different isolators, namely, high damping rubber bearings (HDRB), lead rubber bearings (LRB) and friction pendulum system (FPS). Time history analysis is performed for the bridge with four different earthquake ground motions applied in the longitudinal direction using Newmark's method with linear variation of acceleration over the time interval. The seismic response of the isolated cable-stayed bridge is compared with that of the bridge with no isolation system. The results show that the isolation systems are effective for reducing the absolute acceleration of the deck and the base shear response of the tower. Further, a parametric study is performed by varying the damping ratio, yield strength and friction coefficient of HDRB, LRB and FPS to investigate the influence of these parameters on the seismic response of the bridge. From such a study, optimal values can be found for the isolators for reducing the bridge responses.

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Islam, A. B. M. Saiful, Mohd Zamin Jumaat, Raja Hussain, and Md Ashraful Alam. "INCORPORATION OF RUBBER-STEEL BEARING ISOLATION IN MULTI-STOREY MUILDING." Journal of Civil Engineering and Management 19, Supplement_1 (January 9, 2014): S33—S49. http://dx.doi.org/10.3846/13923730.2013.801904.

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Base isolation incorporation has moved towards a popular technology in the seismic vulnerable regions. The system mitigates lateral action of tremor hazard providing flexibility of structures. Implementing base isolation on buildings in the soil and seismic condition of medium risk seismicity is currently an important issue. A thorough investigation is of burning need for buildings to be incorporated with base isolator and to carry out dynamic analysis. The study provides incorporation of rubber-steel bearings and focuses on the structural changes. Designs of base isolation bearings are performed along with structural viability check. Lead rubber bearing (LRB) and high damping rubber bearing (HDRB) have been inserted on the corresponding structural bases. In finite-element approach, link element simulates the bearing. Bi-linear hysteretic behaviour is presented for LRB and equivalent linear model simulated HDRB. Linear static, free vibration and dynamic frequency-domain analyses are performed for both isolated and non-isolated buildings under bidirectional site-specific earthquake. The study reveals that for multi-storey buildings, isolation can drastically reduce seismic responses. Furthermore, flexibility of buildings predicts some structural savings for reduced responses. Good agreement has been achieved through rapid solution in frequency-domain approach. In medium risk earthquake-prone area, rubber-steel bearing isolators can be beneficially inserted.

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Chirat, E., M. Perez-payo, P. Zimmermann, J. Kac, M. Ducreux, M. Bonomi, A. Gerbaulel, and P. Rougier. "104Treatment of oesophagus cancer by high dose rate brachytherapy(HDRB)." Radiotherapy and Oncology 47 (May 1998): S26. http://dx.doi.org/10.1016/s0167-8140(98)80109-6.

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Beriwal, Sushil, Dwight E. Heron, Robert Mogus, Robert P. Edwards, Joseph L. Kelley, and Paniti Sukumvanich. "High-dose-rate brachytherapy (HDRB) for primary or recurrent vaginal cancer." Brachytherapy 6, no. 2 (April 2007): 115. http://dx.doi.org/10.1016/j.brachy.2007.02.126.

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Chirat, E., P. Zimmermann, H. Marsiglia, A. Gerbaulet, and Ph Rougier. "170 Treatment of oesophagus cancer by high dose rate brachytherapy (HDRB)." Radiotherapy and Oncology 39 (May 1996): S43. http://dx.doi.org/10.1016/0167-8140(96)87971-0.

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Greco, R., G. C. Marano, and M. Mezzina. "The performance of HDRB devices in base isolation: A stochastic sensitivity analysis." Journal of Structural Control 8, no. 2 (December 2001): 203–18. http://dx.doi.org/10.1002/stc.4300080203.

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Martin, Jarad, Paul Keall, Shankar Siva, Peter Greer, David Christie, Kevin Moore, Jason Dowling, et al. "TROG 18.01 phase III randomised clinical trial of the Novel Integration of New prostate radiation schedules with adJuvant Androgen deprivation: NINJA study protocol." BMJ Open 9, no. 8 (August 2019): e030731. http://dx.doi.org/10.1136/bmjopen-2019-030731.

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IntroductionStereotactic body radiotherapy (SBRT) is a non-invasive alternative to surgery for the treatment of non-metastatic prostate cancer (PC). The objectives of the Novel Integration ofNew prostate radiation schedules with adJuvant Androgen deprivation (NINJA) clinical trial are to compare two emerging SBRT regimens for efficacy with technical substudies focussing on MRI only planning and the use of knowledge-based planning (KBP) to assess radiotherapy plan quality.Methods and analysisEligible patients must have biopsy-proven unfavourable intermediate or favourable high-risk PC, have an Eastern Collaborative Oncology Group (ECOG) performance status 0-1 and provide written informed consent. All patients will receive 6 months in total of androgen deprivation therapy. Patients will be randomised to one of two SBRT regimens. The first will be 40 Gy in five fractions given on alternating days (SBRT monotherapy). The second will be 20 Gy in two fractions given 1 week apart followed 2 weeks later by 36 Gy in 12 fractions given five times per week (virtual high-dose rate boost (HDRB)). The primary efficacy outcome will be biochemical clinical control at 5 years. Secondary endpoints for the initial portion of NINJA look at the transition of centres towards MRI only planning and the impact of KBP on real-time (RT) plan assessment. The first 150 men will demonstrate accrual feasibility as well as addressing the KBP and MRI planning aims, prior to proceeding with total accrual to 472 patients as a phase III randomised controlled trial.Ethics and disseminationNINJA is a multicentre cooperative clinical trial comparing two SBRT regimens for men with PC. It builds on promising results from several single-armed studies, and explores radiation dose escalation in the Virtual HDRB arm. The initial component includes novel technical elements, and will form an important platform set for a definitive phase III study.Trial registration numberANZCTN 12615000223538.

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Hernández-Ruiz, L., J. O. Hernández-Oviedo, D. Ruesga-Vazquez, and T. Rivera-Montalvo. "Dose distribution response in HDRB measured with EBT2 and compared with PLATO SYSTEM." Applied Radiation and Isotopes 83 (January 2014): 218–21. http://dx.doi.org/10.1016/j.apradiso.2013.07.015.

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Gheryani, Muna H., Hashim Abdul Razak, and Mohammed Jameel. "Dynamic Response Changes of Seismic Isolated Building Due to Material Degradation of HDRB." Arabian Journal for Science and Engineering 40, no. 12 (August 8, 2015): 3429–42. http://dx.doi.org/10.1007/s13369-015-1794-7.

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Ibrahim, Ardiansyah, Erma Desmaliana, and Amatulhay Pribadi. "Kajian Respon Bangunan Menggunakan Base Isolator pada Gedung Bertingkat Sistem Pracetak dan Sistem Cast in Situ. (Hal. 50-61)." RekaRacana: Jurnal Teknil Sipil 5, no. 1 (March 29, 2019): 50. http://dx.doi.org/10.26760/rekaracana.v5i1.50.

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ABSTRAKIndonesia merupakan wilayah yang memiliki resiko gempa yang cukup tinggi karena terletak pada pertemuan tiga lempeng tektonik,oleh karena itu telah dikembangkan metode desain alternatif dengan tujuan untuk mengurangi resiko kerusakan bangunan akibat beban gempa yang dikenal dengan nama sistem isolasi gempa (seismic isolation).Pada bangunan ini dipasang base isolator jenis High Damping Rubber Bearing (HDRB) dengan diameter 600 mm dan tinggi 407,9 mm.Berdasarkan hasil, diperoleh bahwa penggunaan base isolator dapat memperpanjang periode struktur bangunan dua kali untuk kedua sistem, kemudian dapat mereduksi gaya geser arah X mencapai 40% dan arah Y mencapai 50% untuk kedua sistem, lalu memperkecil simpangan antar lantai dan juga membutuhkan waktu yang lebih singkat untuk mencapai faktor partisipasi modal yang diinginkan sesuai peraturan yaitu minimal 90%. Kesimpulan dari penelitian ini adalah struktur bangunan beton pracetak lebih efektif dibandingkan dengan beton cast in situ dari aspek respon struktur.Kata kunci: pracetak, cast in situ, high damping rubber bearing ABSTRACTIndonesia is prone to seismic hazard load due to its location situated on a meeting point of three tectonic plates, therefore the alternative design methods have been developed with the aim to reduce the risk of damage to buildings due to the load known as the earthquake isolation system. At one of the building analyzed in this research was provided with High Damping Rubber Bearing (HDRB) with a diameter of 600 mm and a height of 407,9 mm. Based on the results obtained, the use of base isolator can extend the period of the structure of the building twice forboth systems, reduce the shear force reached 40% in the X direction and 50% in the Y direction for both systems, and then minimize the deviation between floors of a building and also requires less time to achieve the desired modal participation factors according the regulations that is at least 90%. The conclusion of this research is that the structure of precast concrete is more effective than cast in situ concrete from the aspect of structure response.Keywords: precast, cast in situ, high damping rubber bearing

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Panettieri, V., T. Rancati, E. Onjukka, R. L. Smith, M. A. Ebert, D. J. Joseph, J. W. Denham, A. Steigler, and J. L. Millar. "PV-0321: Influence of urethra contouring on NTCP models predicting urethral strictures in prostate HDRB." Radiotherapy and Oncology 127 (April 2018): S170. http://dx.doi.org/10.1016/s0167-8140(18)30631-5.

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Aldrebi, Ziad Ahmad. "Most suitable types of seismic isolation for use in old mosques in Syria." Earthquake Engineering. Construction Safety, no. 1 (February 25, 2021): 57–77. http://dx.doi.org/10.37153/2618-9283-2021-1-57-77.

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The article discusses the most suitable base isolation bearings from the author's point of view for use in the buildings of old mosques in Syria, which are designed to protect such buildings from the effects of earthquakes that can occur at any time. Especially since many of such buildings have an architectural and cultural value, and are included in the world heritage list of UNESCO. Elastomeric bearings with high energy dissipation capacity (HDRB), elastomeric bearings with lead cores (LDRB), single friction pendulum, double friction pendulum and triple friction pendulum sliding (FPS) bearings are considered. What they consist of, their characteristics. Three, mosques in Syria that are of a great value from the point of view of architecture and cultural heritage are listed and described, and conclusions are drawn.

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Cancellara, Donato, and Fabio de Angelis. "Seismical Protection Properties of High Damping Rubber Bearing and Lead Rubber Bearing Base Isolation Systems for Multi-Storey RC Buildings." Applied Mechanics and Materials 234 (November 2012): 90–95. http://dx.doi.org/10.4028/www.scientific.net/amm.234.90.

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In the present paper two different base isolation systems, designed and verified according to the european seismic code (EC2 and EC8), are compared for evaluating the behaviour of a base isolated building, highly irregular in plan, in presence of a seismic excitation. The devices adopted for realizing the different base isolation systems are the High Damping Rubber Bearing (HDRB) and the Lead Rubber Bearing (LRB) both of them actuated in parallel with a Friction Slider (FS). A dynamic nonlinear analysis for a three-dimensional base isolated structure has been performed. Recorded accelerograms for bi-directional ground motions, compatible with the reference elastic response spectrum for each limit state have been used for a more realistic evaluation of the seismic response of the structure and a more realistic comparative analysis between the base isolated structure with the different considered base isolation systems and the traditional fixed base structure.

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Mira, J. G., R. Swanton, J. Hevezi, and C. DeMoor. "493 Evaluation of hi-dose rate brachytherapy (HDRB) for intra-bronchial obstruction due to lung cancer." Lung Cancer 18 (August 1997): 127. http://dx.doi.org/10.1016/s0169-5002(97)89873-x.

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Aisen, S., HA Carvalho, JV Petitto, W. Nadalin, and CMK Haddad. "High dose rate brachytherapy (HDRB) in the treatment of carcinoma of the uterine cervix—Brazilian experience." International Journal of Radiation Oncology*Biology*Physics 42, no. 1 (January 1998): 313. http://dx.doi.org/10.1016/s0360-3016(98)80478-1.

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Chapet, S., L. Alcaraz, P. Louisot, A. Reynaud-Bougnoux, P. Bourlier, E. Dorval, O. Le Floch, and G. Calais. "Predictive factors for late toxic effects following high dose rate brachytherapy (HDRB) boost for esophageal cancer (EC)." International Journal of Radiation Oncology*Biology*Physics 51, no. 3 (November 2001): 266. http://dx.doi.org/10.1016/s0360-3016(01)02311-2.

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Panettieri, V., E. Onjukka, T. Rancati, R. Smith, and J. Millar. "PO-0855: Use of the LKB model to fit urethral strictures for prostate patients treated with HDRB." Radiotherapy and Oncology 123 (May 2017): S465. http://dx.doi.org/10.1016/s0167-8140(17)31292-6.

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HWANG, J. S., C. F. HUNG, Y. N. HUANG, and S. J. WANG. "DESIGN FORCE TRANSMITTED BY ISOLATION SYSTEM COMPOSED OF LEAD-RUBBER BEARINGS AND VISCOUS DAMPERS." International Journal of Structural Stability and Dynamics 10, no. 02 (June 2010): 287–98. http://dx.doi.org/10.1142/s0219455410003440.

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In seismic isolation design of structures located at soft soil sites or near field areas, viscous dampers (VD) are often included as part of the isolation system to minimize its maximum displacement. Due to the 90° phase angle existing between the force and displacement of the VD, the maximum force transmitted by the isolation system cannot be calculated by simply combining the forces of the isolation bearings, such as lead-rubber bearings (LRB) or high damping rubber bearings (HDRB), and VD in association with the design displacement. Conforming to the code-specified equivalent lateral response procedure for isolation design, this paper presents a formula for determining the seismic design force of the combined LRB and VD isolation system, taking into account the phase angle between the combined force of the LRB and VD and the displacement of the isolation system. The numerical results have shown that the maximum responses of the isolation system predicted by the proposed formula are conservative and comparable with those from the inelastic dynamic response history analysis.

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Cancellara, Donato, and Fabio de Angelis. "Seismic Analysis and Comparison of Different Base Isolation Systems for a Multi-Storey RC Building with Irregularities in Plan." Advanced Materials Research 594-597 (November 2012): 1788–99. http://dx.doi.org/10.4028/www.scientific.net/amr.594-597.1788.

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In the present paper the dynamic nonlinear analysis for a 3D base isolated structure is illustrated. A base isolated reinforced concrete building is designed and verified according to the European seismic codes such that the superstructure remains almost completely elastic and the nonlinear elements are localized only in the base isolation system. Nonlinear hysteretic models have been adopted to reproduce the cyclic behavior of the isolators. Two different base isolation systems are considered and their performances are compared for evaluating the behaviour of a base isolated building, highly irregular in plan, in presence of a seismic excitation defined with recorded accelerograms which characterize the bi-directional ground motions. The isolation system has been realized with a combination in parallel of elastomeric bearings and sliding devices. In the first analyzed isolation system we have used the High Damping Rubber Bearings (HDRB) and in the second analyzed isolation system we have used the Lead Rubber Bearings (LRB). Finally a comparative analysis between the base isolated structure with hybrid base isolation systems and the conventional fixed base structure is detailed.

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Bai, Ben Du, Wei Hua Liu, Ying Liu, and Jiu Lun Fan. "Recent Advances in High Dynamic Range Imaging." Applied Mechanics and Materials 441 (December 2013): 699–702. http://dx.doi.org/10.4028/www.scientific.net/amm.441.699.

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This paper aims to present a review of recent techniques in high dynamic range imaging (HDRI), which was the topic in research areas including image processing, computer graphics, and photography. HDRI or just HDR is a set of techniques that allows a greater dynamic range between the lightest and darkest areas of an image than current standard digital imaging techniques or photographic methods. HDR imaging technologies will spread its sphere of influence in imaging industry for its high quality and its powerful expression ability, including digital cinema, digital photography and next generation broadcast. This paper discusses recent advances, future direction in HDRI. The major goal of the paper is to provide a reference source for the researchers involved in HDRI, regardless of particular application areas.

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Rico Pradilla, Leocadio, and Gustavo Chio Cho. "Uso de aisladores de base en puentes de concreto simplemente apoyados." Revista Tecnura 16, no. 34 (December 4, 2012): 103. http://dx.doi.org/10.14483/udistrital.jour.tecnura.2012.4.a08.

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En el presente artículo se presenta una comparación del comportamiento sísmico de puentes de concreto reforzado simplemente apoyados, usando aisladores de base de tres tipos, los aisladores de elastoméricos de alto amortiguamiento HDRB por sus siglas en inglés (High Damping Rubber Bearings), los aisladores elastoméricos con núcleo de plomo LRB (Lead Rubber Bearings) y el sistema de péndulo de fricción FPS (Friction Pendulum System). Se tomó como caso de estudio el viaducto la flora, definiéndose la geometría y su correspondiente modelamiento en SAP2000. Se definieron las propiedades mecánicas de los tres aisladores usando un modelo bilineal; para el modelo del viaducto se realizó un análisis dinámico no lineal de historias en el tiempo, considerando la no linealidad en los aisladores, usando los sismos de la falla Frontal y la falla Bucaramanga-Santa Marta, escalados a nivel de superficie. Se compararon los resultados del modelo sin aislamiento sísmico versus los tres modelos con sistema de aislamiento sísmico, y se encontró que los diferentes sistemas de aislamiento sísmico reducen significativamente la demanda de los desplazamientos y fuerzas cortantes en las pilas del puente que le inducen los probables terremotos que puedan ocurrir.

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Daniel, Sarah E., Thomas Carion, Edward Schervish, Rene Frontera, Amr M. Aref, Cynthia Holland Browne, Todd Campbell, and Paul J. Chuba. "Combination external beam and brachytherapy for intermediate- to high-risk prostate cancer: Comparison of high-dose rate (HDR) and seed (LDR) implant methods." Journal of Clinical Oncology 33, no. 7_suppl (March 1, 2015): 90. http://dx.doi.org/10.1200/jco.2015.33.7_suppl.90.

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90 Background: Maximizing the therapeutic ratio for intermediate to high risk localized prostate cancer may be accomplished by using a combination of external beam radiotherapy (EBRT) and radiation implant. Differences in implant methods could be expected to influence mortality. We compared outcomes for patients treated using combination EBRT and high dose rate (HDR) versus EBRT and low dose rate (LDR) seed implant methods. Methods: Between 12/1993 and 05/2010 there were 307 cases of combination therapy with analyzable data: 227 HDR + EBRT (HDRe) and 81 LDR + EBRT (LDRe) Intermediate risk patients had 1+ risk factors: PSA ≥ 10, Gleason score (GS) ≥ 7, or AJCC clinical stage ≥ T2b. High risk patients exhibited either 2+ of these risk factors or PSA ≥ 20, GS ≥ 8, or AJCC clinical stage ≥ T3. External beam radiation was 45 Gy in 1.8 Gy daily fractions using 3D conformal or IMRT methods. The prostate, seminal vesicles, and (in some patients) pelvic lymph nodes were treated. HDR brachytherapy was delivered one week prior to beginning EBRT. Afterloading HDR catheter needles were surgically implanted into the prostate. HDR dose was 21 Gy in three equal fractions of 7 Gy peripheral dose given over two days. LDR was performed 2-3 weeks after EBRT using I-125 or Pd-103 seeds and 109 or 90 Gy respectively. PSA failure was defined as “nadir plus two.” Results: HDRe and LDRe cases were well matched for pretreatment risk factors. There were 18 PSA failures in the HDRe group (7.9%) and 6 PSA failures in the LDRe group (7.4%). Adjusted Cox proportional hazard models showed no statistically significant difference between the treatment groups with regard to PSA failure. Hazard ratio for LDRe compared to HDRe was 0.82 (95% CI 0.28, 2.46; p=0.73). There were 26 deaths from any cause (11.45%) in the HDRe group and 11 deaths from any cause (13.58%) in the LDRe group. Adjusted Cox models showed no statistically significant difference between the treatment groups for survival. Hazard ratio for LDRe compared to HDRe was 1.49 (95% CI 0.68, 3.25; p=0.32). Conclusions: There were no statistically significant differences in PSA failure free survival or overall survival detected in LDRe versus HDRe patient groups.

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Okinaga, Toshinori, Guoqing Niu, Zhoujie Xie, Fengxia Qi, and Justin Merritt. "The hdrRM Operon of Streptococcus mutans Encodes a Novel Regulatory System for Coordinated Competence Development and Bacteriocin Production." Journal of Bacteriology 192, no. 7 (January 29, 2010): 1844–52. http://dx.doi.org/10.1128/jb.01667-09.

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ABSTRACT The Streptococcus mutans hdrRM operon encodes a novel two-gene regulatory system induced by high cell density. Previous studies identified hdrM as the only known negative regulator of competence development in S. mutans. In the present study, we demonstrated that the HdrRM system bypasses the prototypical competence gene regulators ComC and ComDE in the transcriptional regulation of the competence-specific sigma factor comX and the late competence genes. Similarly, the HdrRM system can abrogate the requirement for ComE to produce the bacteriocin mutacin IV. To further probe the regulatory mechanism of hdrRM, we created an hdrR overexpression strain and showed that it could reproduce each of the hdrM competence and mutacin phenotypes, indicating that HdrM acts as a negative regulator of HdrR activity. Using a mutacin IV-luciferase reporter, we also demonstrated that the hdrRM system utilizes the same promoter elements recognized by ComE and thus appears to comprise a novel regulatory pathway parallel to ComCDE.

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B S, Poornima. "Comparative Study on Seismic Response of Regular and Irregular RC Framed Buildings with HDRB, LRB and FPS Base Isolation Systems." International Journal for Research in Applied Science and Engineering Technology 7, no. 6 (June 30, 2019): 805–13. http://dx.doi.org/10.22214/ijraset.2019.6140.

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Brune, D., J. E. Couette, F. Lesaunier, and D. Benabid. "153 Post-operative vaginal high dose rate brachytherapy (HDRB) in endometrial carcinoma: The experience of centre francois baclesse 1990–1995." European Journal of Cancer 31 (November 1995): S35. http://dx.doi.org/10.1016/0959-8049(95)95408-x.

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Injerd, Russell, Kristen Burnham, Matthew Walb, Bruce Hershatter, Sagar A. Patel, and Benjamin Walker Fischer-Valuck. "Normal tissue complication probabilities (NTCP) of urethral stricture following salvage SBRT or HDR for periurethral recurrences following prior definitive radiation therapy." Journal of Clinical Oncology 39, no. 6_suppl (February 20, 2021): 246. http://dx.doi.org/10.1200/jco.2021.39.6_suppl.246.

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246 Background: SBRT and HDR brachytherapy have emerged as definitive salvage re-irradiation options for men with locally recurrent prostate cancer after prior radiation therapy (RT). Toxicity with re-irradiation remains a concern in this setting, particularly for salvage of periurethral recurrences. We calculated the normal tissue complication probability (NTCP) of urethral stricture following salvage re-irradiation (HDR and SBRT) after previous definitive RT (external beam or HDR) for periurethral recurrences. Methods: Two upfront definitive treatment plans were generated for 5 men with localized prostate cancer: External Beam RT (EBRT1) to a dose of 79.2 Gy in 1.8 Gy fractions and HDR monotherapy (HDR1), 13.5 Gy x 2 implants. Periurethral recurrences were virtually created on diagnostic MRI scans for each of the five men and defined as a recurrent dominant intraprostatic lesion (DIL). Three salvage RT plans were generated for each patient (constraints in Table): HDR salvage (10 Gy whole gland; 13.5 Gy to DIL; 2 implants), SBRTr with maximal rectal sparing (constraints designed for salvage following prior EBRT; 30 Gy in 5 fractions whole gland; 40 Gy in 5 fractions to DIL), and SBRTu with maximal urethral sparing (constraints designed for patients with prior HDR monotherapy; same Rx). DVH data was collected for each plan (previous RT and each salvage approach) and the equivalent uniform dose (EUD) was calculated. NTCP for the urethral stricture in the summed plans (prior definitive treatment + each salvage plan) was calculated by the Lyman-Kutcher-Burman model using the following parameters: (α/β = 5Gy; TD50= 116.7; m = 0.23; n = 0.3). Results: Prescription coverage of 90% of the DIL volume was achieved for each plan. The mean NTCP of urethral stricture for EBRT1 + HDR salvage was 55.2% (range, 52.2-59.1%) and for HDR1 + HDR salvage was 49.2% (42.9-57.5%). For EBRT1 + SBRTr and EBRT1 + SBRTu the NTCP for urethral stricture was 54.0% (50.4-61.0%) and 43.2% (39.4-48.4%), respectively. The NTCP of urethral stricture for HDR1 + SBRTr was 48.1% (41.0-57.2%) and for HDR1 + SBRTu was 37.6% (30.9-44.6%). Conclusions: In this modeling analysis of salvage RT for periurethral recurrences following previous RT (EBRT or HDR monotherapy), the NTCP for urethral stricture was numerically lowest for salvage SBRT using maximum urethral sparing dose constraints in comparison to salvage SBRT with maximum rectal sparing constraints or salvage HDR brachytherapy. This type of analysis lends insight into personalized treatment planning based on previous RT modality and previous dose to organs at risk. Expanded analysis is underway. [Table: see text]

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Barney, Katelyn. "Community gets you through: Success factors contributing to the retention of Aboriginal and Torres Strait Islander Higher Degree by Research (HDR) students." Student Success 9, no. 4 (November 30, 2018): 13–23. http://dx.doi.org/10.5204/ssj.v9i4.654.

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This paper explores success factors contributing to the retention of Aboriginal and Torres Strait Islander Higher Degree by Research (HDR) students identified through a National Teaching Fellowship. Interviews with Indigenous HDR graduates are analysed to explore inhibiting and success factors to completing an HDR. While the fellowship focused mostly on building successful pathways from undergraduate study into HDRs, interviewees also discussed success factors for completing an HDR. In order to address Indigenous student retention and success in higher education, finding out what contributes to successful HDR completions for Indigenous students across diverse disciplines is critical.

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Chen, Zhe Bo, Jin Xu, Bin Lin, Xu Xiang Ni, and Zu Kang Lu. "A HDRI Camera Based on SLM." Key Engineering Materials 364-366 (December 2007): 1237–41. http://dx.doi.org/10.4028/www.scientific.net/kem.364-366.1237.

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A high dynamic range image camera (HDRI) is a kind of camera which captures the HDRI image. HDRI means the image with high dynamic range, it can record the gray information of the object with much wider dynamic range. HDR image has great applications in many fields. The existing HDRI camera needs either the special image sensor or can capture the still object only. In this paper, a new kind of camera is proposed. In this camera, a space light modulator (SLM) is used to acquire images with different exposure, then a HDRI is made with these images. This camera can acquire dynamic image and it is cheap and easy to extend.

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Opio, Christopher, Kona van Diest, and Norman Jacob. "Intra-Seasonal Changes in Height to Diameter Ratios for Lodgepole Pine in the Central Interior of British Columbia." Western Journal of Applied Forestry 18, no. 1 (January 1, 2003): 52–59. http://dx.doi.org/10.1093/wjaf/18.1.52.

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Abstract Height to diameter ratio (HDR) has been proposed as an alternative to conventional procedures for assessing competition between crop trees and other vegetation. Yet HDRs vary throughout the growing season due to variations in the rate of change in height and diameter. There is an interest, therefore, in determining variations in HDR within a growing season (intra-seasonal changes) and the time of the year when measurements of HDR should be taken for operational purposes. HDR measurements were taken on five occasions at two lodgepole pine (Pinus contorta var. latifolia) sites in the central interior of British Columbia, from early May to late October through the 1999 growing season. Although the focus of the article is the investigation of intra-seasonal changes in HDR, we also compared August 1999 measurements with August 1998 measurements to determine the variation in HDR between growing seasons (inter-seasonal change). The study involved a completely randomized, one-factor experimental design, with replication over time. The removal of competing vegetation (known as brushing) was the factor. The design consisted of four levels of brushing, replicated three times on each study site. The results indicated that HDRs increased from early May to July and then decreased until October to levels equal to or lower than those obtained in August 1998. The highest HDR values were observed in control plots. The analysis of variance (ANOVA) with repeated measures indicated that treatment (brushing radius) and date of HDR measurement had significant (P < 0.05) effects on the intra-seasonal changes in HDR. The results suggest that HDR measurements should be taken either after mid-August, or before mid-May when changes in HDR are negligible. West. J. Appl. For.18(1):52–59.

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Fornés, Nélida Schmid, Maria Luiza Ferreira Stringhini, and Berenice Müller Elias. "Reproducibility and validity of a food-frequency questionnaire for use among low-income Brazilian workers." Public Health Nutrition 6, no. 8 (December 2003): 821–27. http://dx.doi.org/10.1079/phn2003505.

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AbstractObjectives:To assess the reproducibility and validity a 127-item, habitual intake, food-frequency questionnaire (FFQ), developed for low-income and low-literacy Brazilian workers, by comparison with a 24-hour dietary recall (24-HDR).Design:The FFQ and 24-HDR were interviewer-administered at the local workplace to each subject twice, with a period of 6 months between estimates; and four 24-HDRs were conducted during the 4-month period between the two FFQs (FFQ1 and FFQ2). Reproducibility was tested by comparing mean nutrient intakes from the two FFQs. Validity was determined by comparing the mean nutrient intakes from the FFQs with the corresponding averages of the six 24-HDRs (reference method).Setting:Goiânia City, in Central West Brazil.Subjects:The study was based on 104 (62 women and 42 men) subjects, aged 18 to 60 years, who were randomly selected.Results:Dietary intake from the FFQ was higher than from the 24-HDR. Reproducibility was assessed by Pearson correlation coefficients for nutrients from FFQ1 and FFQ2, and ranged from 0.23 for retinol to 0.69 for total energy (mean 0.52). Intra-class coefficients for nutrients averaged by the 24-HDRs ranged from 0.29 for vitamin C to 0.76 for total energy; retinol was not significant. In the validation study, correlation between the FFQ and the 24-HDR ranged between 0.21 for vitamin C and 0.70 for total energy (mean 0.50). Adjusting for total energy lowered the coefficients, except for calcium, retinol and vitamin C. Coefficients increased with attenuation, ranging from 0.35 for carbohydrate to 0.65 for calcium.Conclusions:Results indicate that this questionnaire had satisfactory reproducibility and reasonable validity.

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Lederer, A., K. H. Kunzelmann, R. Hickel, and F. Litzenburger. "Transillumination and HDR Imaging for Proximal Caries Detection." Journal of Dental Research 97, no. 7 (February 26, 2018): 844–49. http://dx.doi.org/10.1177/0022034518759957.

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The purpose of this study was to develop an in vitro model for the validation of near-infrared transillumination (NIRT) for proximal caries detection, to enhance NIRT with high-dynamic-range imaging (HDRI), and to compare both methods, using micro-computed tomography (µCT) as a reference standard. Both proximal surfaces of 53 healthy or decayed permanent human teeth were examined using the Diagnocam (DC) (KaVo) and NIRT with HDRI (NIRT-HDRI). NIRT was combined with HDRI to improve the diagnostic performance by reducing under- and overexposed image areas. For NIRT-HDRI, an exposure series was captured and merged into a single HDR image. A classification was applied according to lesion depth. All surfaces were assessed twice by 2 trained examiners, and additionally with µCT for validation. The Kappa statistic was used to calculate inter-rater reliability and agreement between DC and NIRT-HDRI. Inter-rater reliability (weighted Kappa, wκ) showed very good agreement for the DC (0.90) and NIRT-HDRI (0.96). The overall agreement (wκ) was almost perfect (0.85). In the individual categories (0 to 4), the agreement (simple Kappa) ranged from almost perfect (category 4) to moderate (1 and 2) to substantial (categories 0 and 3). Sensitivity and specificity of sound surfaces, enamel, and dentin caries ranged from 0.57 to 0.99 and were similar for both methods in the different categories. NIRT-HDRI had a higher sensitivity for sound surfaces and enamel caries, as well as a higher specificity for dentin caries. Regarding the obtained images, HDRI allowed for the detection of caries within a greater range of luminance levels, resulting in a more detailed visualization of structures without under- or overexposure. However, HDRI this did not improve the diagnostics significantly. Distinguishing between a processed demineralized enamel and dentin lesions appears to be a problem specific to NIRT and cannot be balanced using HDRI.

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Kocic, Sanja, Dragan Vasiljevic, Snezana Radovanovic, Svetlana Radevic, Ivana Simic Vukomanovic, and Natasa Mihailovic. "Possible Uses of Data from Hospital Discharge Reports." Serbian Journal of Experimental and Clinical Research 18, no. 2 (June 1, 2017): 163–67. http://dx.doi.org/10.1515/sjecr-2016-0023.

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AbstractAlmost all countries in the world keep some form of hospital discharge report (HDR). Although there are many variations, every report contains such data as patient demographics, the main cause of hospitalization, comorbidities, the length of stay in hospital and outcome. The advantages of using data obtained from HDRs are numerous: The data from HDRs are already collected in a designated centre and thus easily available and relatively cheap; HDRs contain information for many previous years; they are sometimes more reliable than data obtained through any other method; and finally, they provide a large and representative database. HDRs databases can be connected with other databases using a unified patient identification number. The limitations of using data obtained through HDRs are as follows: inconsistencies in defining and coding diagnoses and applied procedures, common underestimations of comorbidity, limited possible applications in specific studies and partial coverage of inpatient institutions. The prediction that in the future, a growing number of diagnostic and treatment procedures will be performed on an outpatient basis will also limit the use of HDRs. When electronic recordkeeping becomes a practice, we may assume that these data will no longer be needed. There is no perfect model for collection and processing data regarding hospitalized patients. HDRs, with their advantages and disadvantages, currently represent the best way to perceive the size, type, quality and efficiency of the health care services provided to patients at the secondary and tertiary level.

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Koyfman, S., V. V. Thakkar, J. J. Juliano, D. A. Wilkinson, C. A. Reddy, and P. A. Fleming. "Definitive Twice Daily High-dose Rate Brachytherapy (HDRB), with or without Pelvic External Beam Radiotherapy (RT), for the Treatment of Medically Inoperable Stage I Uterus Cancer." International Journal of Radiation Oncology*Biology*Physics 75, no. 3 (November 2009): S360—S361. http://dx.doi.org/10.1016/j.ijrobp.2009.07.826.

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STEVENS, M., J. SAALFELD, P. BRENNER, and R. KOONER. "13 Treatment of localised prostate cancer using a combination of high dose-rate Ir-192 brachytherapy (HDRB) and external beam radiation therapy (EBRT): a 7 year experience." BJU International 97 (March 2006): 3–4. http://dx.doi.org/10.1111/j.1464-410x.2006.06085_13.x.

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Siero, Jeroen CW, Natalia Petridou, Hans Hoogduin, Peter R. Luijten, and Nick F. Ramsey. "Cortical Depth-Dependent Temporal Dynamics of the BOLD Response in the Human Brain." Journal of Cerebral Blood Flow & Metabolism 31, no. 10 (April 20, 2011): 1999–2008. http://dx.doi.org/10.1038/jcbfm.2011.57.

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Recent animal studies at high field have shown that blood oxygen level-dependent (BOLD) contrast can be specific to the laminar vascular architecture of the cortex, by differences in its temporal dynamics in reference to cortical depth. In this study, we characterize the temporal dynamics of the hemodynamic response (HDR) across cortical depth in the human primary motor and visual cortex, at 7T and using very short stimuli and with high spatial and temporal resolution. We find that the shape and temporal dynamics of the HDR changed in an orderly manner across cortical depth. Compared with the pial vasculature, HDRs in deeper gray matter are significantly faster in onset time (by ∼ 0.5 second) and peak time (∼2 seconds), and are narrower (by ∼1 second) and with smaller amplitude, in line with the known vascular organization across cortical depth and the transit of deoxygenated blood through the vasculature. The width of the HDR in deeper gray matter was as short as 2.1 seconds, indicating that neurovascular coupling takes place at a shorter timescale than previously reported in the human brain. These findings open the possibility to probe layer-specific hemodynamics and neurovascular coupling mechanisms in human gray matter.

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Benzel, Edward C., and Sanford J. Larson. "Operative Stabilization of the Posttraumatic Thoracic and Lumbar Spine: A Comparative Analysis of the Harrington Distraction Rod and the Modified Weiss Spring." Neurosurgery 19, no. 3 (September 1, 1986): 378–85. http://dx.doi.org/10.1227/00006123-198609000-00008.

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Abstract To assess the efficacy of operative stabilization techniques, a retrospective study of Harrington distraction rod (HDR) and modified Weiss spring instrumentation was performed in 90 patients. An operation was performed for one or both of two indications: persistent spine instability or the presence of a neurological deficit in patients with incomplete neurological injuries and myelographic evidence of spinal cord or cauda equina compression. The lateral extracavitary operative approach to the spine for decompression and anterior interbody fusion was performed with an accompanying HDR (47 patients) or modified Weiss spring placement (43 patients). Eight HDRs failed, resulting in gross instability (17 per cent) that either resulted in further neurological injury (1 patient), further surgery (2 patients), or increased morbidity secondary to prolonged bed rest (5 patients). One Weiss spring failed, requiring further surgery (2.3 per cent). Nonsurgical complications were similar in both groups and appeared to be unrelated to the type of instrumentation utilized. The modified Weiss spring instrumentation technique, which offers a dynamic compression fixation of the spine, was clearly superior to the HDR technique, which offers a rigid distraction fixation. The biomechanics of distraction versus compression and rigid versus nonrigid spine stabilization are discussed.

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Dabic-Stankovic, Kata, Katarina Rajkovic, Miodrag Acimovic, Nebojsa Milosevic, and Jovan Stankovic. "A quantitative analysis of two-dimensional manually segmented transrectal ultrasound axial images in planning high dose rate brachytherapy for prostate cancer." Vojnosanitetski pregled 74, no. 5 (2017): 420–27. http://dx.doi.org/10.2298/vsp150901231d.

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Background/Aim. Prostate delineation, pre-planning and catheter implantation procedures, in high-dose rate brachytherapy (HDR-BT), are commonly based on the prostate manually segmented transrectal ultrasound (TRUS) images. The aim of this study was to quantitatively analyze the consistency of prostate capsule delineation, done by a single therapist, prior to each HDR-BT fraction and the changes in the shape of the prostate capsule during HDR-BT, using two dimensional (2D) TRUS axial image. Methods. A group of 16 patients were treated at the Medical System Belgrade Brachytherapy Department with definitive HDRBT. The total applied median dose of 52 Gy was divided into four individual fractions, each fraction being delivered 2? 3 weeks apart. Real time prostate axial visualization and the manual segmentation prior to each fraction were performed using B-K Medical ultrasound. Quantitative analyses, analysis of an area and shape were applied on 2D-TRUS axial images of the prostate. Area analyses were used to calculate the average value of the cross-sectional area of the prostate image. The parameters of the prostate shape, the fractal dimension and the circularity ratio of the prostate capsule contour were estimated at the maximum axial cross section of the prostate image. Results. The sample group consisted of four phases, each phase being performed prior to the first, second, third and fourth HDR-BT fraction, respectively. Statistical analysis showed that during HDR-BT fractions there were no significant differences in the average value of area, as well as in the maximum shape of prostate capsule. Conclusions. Quantitative analysis of TRUS axial prostate segmented images shows a successful capsule delineation in the series of manually segmented TRUS images, and the prostate maximum shape remaining unchanged during HDR-BT fractions.

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Staehler, Michael D., Behr Lisa, Philipp Nuhn, Boris Schlenker, and Ralf Wilkowski. "Comparison of simultaneous high dose stereotactic radiotherapy with normofractionated radiotherapy in patients with metastatic renal cell carcinoma under systemic therapy." Journal of Clinical Oncology 33, no. 7_suppl (March 1, 2015): 467. http://dx.doi.org/10.1200/jco.2015.33.7_suppl.467.

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467 Background: Conventional radiation therapy (RT) is considered ineffective in metastatic renal cell carcinoma (mRCC). There are data suggesting that this might be related to low doses per fraction and that higher doses could be more effective. We introduced hypofracationated high-dose radiation therapy in patients with an indication for radiotherapy an retrospectively compared the results to patients with a conventional radiation therapy. Methods: We identified 97 pts with mRCC and an indication for radiotherapy of metastatic lesions between 2007 and 2013. All pts underwent simultaneous systemic therapy based on targeted agents and systemic therapy. 83 pts had a hypofractionated high dose stereotactic radiation (HDRT) (5 Gy per fraction, 3 fractions per week, total 45 Gy) while 14 pts underwent conventional normo-fractionated radiotherapy (NDR) (1.8 Gy per fraction) as described elsewhere. Results: Median age was 64.1 years (27-86). 189 metastatic lesions were irradiated. 64% of the pts had clear cell histology, with 14% harboring papillary RCC type II and 11% other subentities. Median overall survival was significantly longer for pts after HDRT was 9.4 months (+/-9.4 months) and 4.5 months (+/- 3.4 months) after NDR (p=0.01). The multivariate cox regression analysis revealed the MSKCC risk score, HDR therapy and the disease free survival as positive predictors for survival. No grade III toxicities were found, with 24% of the patients experiencing grade 1 or 2 side effects, mainly diarrhea and fatigue. Conclusions: In mRCC HDRT with simultaneous systemic therapy is related to a better overall survival than NRT. HDRT in combination with targeted therapy should be regarded the standard of care if RT is indicated.

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Rojas Puentes, Luis Leonardo, Andres Felipe Cardona Zorrilla, Lucely Cetina, Jorge Miguel Otero, Hernan Carranza, and Carlos A. Vargas-Baez. "Prognostic role of microvascular density (DMV), VEGF, EGFR, and HIF-1 α expression and their relationship with epitelial mesenquimal transition (EMT) in patients with locally advanced cervical cancer (LACC) treated with chemoradiotherapy." Journal of Clinical Oncology 31, no. 15_suppl (May 20, 2013): e22028-e22028. http://dx.doi.org/10.1200/jco.2013.31.15_suppl.e22028.

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e22028 Background: In low and middle income countries cervical carcinoma is the second leading cause of death among women. Methods: To describe the prognostic value of MVD and protein expression of several genes related to survival and proliferation and their relationship with EMT of LACC. Overall response rates (ORR), clinical benefit (CB), progression-free survival (PFS), and overall survival (OS) were estimated for women suffering from LACC treated with chemoradiotherapy followed by high dose rate brachytherapy (HDRB). Results: Sixty-one patients were included (mean age 52±10); all of them had LACC (2.3% 2A/47.5% 2B/4.9% 3A/37.7% 3B/3.3% 4A/3.3% not defined), a tumour mean size of 6.4cm (SD±1.8cm) and HPV infection in 46% of the cases. Fifty-eight patients (95%) had a squamous pattern, two were adenocarcinomas and >50% presented moderated or poorly differentiated neoplasms. All of them were treated with chemotherapy (transitory interruption of external radiotherapy was documented in 19% due to toxicity and in 21.4% of cases by other causes/mean cycles of platinum administered during radiotherapy 4.8 ± 1.0) and brachytherapy (77% completed all planed intracavitary treatment). The median PFS and OS was 6.6 months (4.0-9.1) and 30 months (11-48) respectively. None of the variables had effect on PFS, whilst multivariate analysis revealed that VEGF (p=0.026) and EGFR expression levels (p=0.030) and <6 cm tumour volume (p=0.02) positively influenced the OS. TWIST expression and E-cadherine lost expression (E-) also influence OS (p=0.001) and (p=0.02) respectably and are related with VEGF and EGFR expression. When EGFR or VEGF are coexpressed with TWIST or related with E- expression the patients shows the worst OS (median 14 m CI 95% 3-24 m, p=0.02 for EGFR (+) and E- ; VEGF (+) and E - median 14 m CI 95% 3-25 m p=0.0001; EGFR (+) and TWIST (+) 19 m CI 95% 15-80 m, p=0.006; VEGF (+) and TWIST (+) 18 m CI 95% 15-80 m, p=0.0001. Conclusions: Classifying LACC patients treated with cisplatin-based chemoradiotherapy by protein expression and EMT markers had a positive influence on prognosis.

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Journal articles on the topic 'HDRB'

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