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Background Symptoms of pulmonary injury following lung irradiation may not manifest clinically in childhood. We performed comprehensive pulmonary evaluation of patients who had received lung irradiation for treatment of cancer. Materials and methods Patients underwent a focused history and physical examination, computed tomography of the chest, pulmonary function test, and cardiopulmonary exercise stress test (CPET). Health-related Quality of Life was also measured. Results Fourteen patients were recruited with median age of 16 years (range, 6 to 21 y). Median time from pulmonary radiation to testing was 5 years (range, 2 to 11 y). Five patients reported pulmonary symptoms. Twelve patients (85.7%) had at least 1 pulmonary function test abnormality. Nine patients demonstrated CPET abnormalities; 7 patients had abnormal pulmonary limitation to exercise, and 5 patients had exercise-induced bronchospasm. The pulmonary limitations included abnormal ventilatory response to exercise in 5 patients, and gas exchange abnormalities in 4 patients. Chest computed tomography demonstrated grade 1-2 radiation-induced lung changes in 4 patients, and grade 3 abnormalities in 1 patient. Conclusions Significant pulmonary dysfunction was observed in childhood cancer survivors who had received lung irradiation. CPET is feasible in childhood cancer survivors and can be valuable for assessment of pulmonary function and exercise capacity.

Summary Background There is limited data on pulmonary function test (PFT) abnormalities in children treated with modern irradiation techniques. PFT abnormalities have not been correlated with the dose and volume of irradiation. Methods A retrospective chart review of PFTs and clinical outcomes in children who received radiation therapy (RT) at Children's Hospital Los Angeles between 1999 and 2009 was performed. Radiation dose distribution to normal lung tissue was calculated. Results Forty-nine patients had PFTs available post-RT at a median time of 2.91 years (range, 0.01–8.28) from irradiation. Sixty-seven percent of patients had at least one PFT abnormality on their last available study. The most common abnormality was obstructive lung disease (24%) followed by hyperinflation (20%). Thoracic surgery prior to RT increased the odds of an abnormal FEV1, RV/TLC, and obstructive disease. The sex of the patient, age at the time of irradiation, and time of the PFT after irradiation did not have a significant association with abnormalities. The mean lung dose, maximum lung dose, and prescribed dose of radiation were significantly associated with the development of PFT abnormalities. The odds of developing an abnormal PFT increased with increase in the minimum threshold dose (Vdose) of radiation, mostly above V20. Conclusion PFT abnormalities are common even when modern radiation techniques are used. A significant correlation between radiation parameters and PFT abnormalities was noted. Pediatr Pulmonol. 2015; 50:596–603. © 2014 Wiley Periodicals, Inc.

Background Abnormalities in pulmonary function tests (PFT) and clinical symptoms have been reported in up to one third of patients with Hodgkin lymphoma (HL) treated with irradiation. The purpose of this study is to describe the prevalence of pulmonary complications in HL patients treated using contemporary protocols. Procedures Eligible patients at Children's Hospital Los Angeles from 1999 to 2009 were identified from the radiation oncology database. Clinical features, radiographic findings, PFT, and radiation details were retrospectively ascertained. Results The median age at diagnosis of 65 patients with HL was 13.6 years and the median follow-up was 3.7 years. The median prescribed radiation dose was 21 Gy. The prevalence of clinical symptoms was low: chronic cough (3%), dyspnea (9.2%), and supplemental oxygen requirement (1.5%). Radiological interstitial lung changes were observed in 31% of the patients. PFT results following irradiation were available in 38 patients. Forced expiratory volume in 1 second (FEV1) and forced expiratory flow 25–75% (FEF25–75%) were decreased in 13% and 11% of patients respectively. Residual volume (RV) was elevated in 21%. Total Lung capacity (TLC) was decreased in 8%. Age at irradiation (P = 0.004), maximum lung dose (P = 0.03), and volume of lung receiving >25 Gy were associated with development of adverse pulmonary outcomes on univariate analysis. On multivariate analysis, older age was associated with worse outcomes. Conclusion In survivors of pediatric HL, involved field irradiation was accompanied by a low prevalence of pulmonary symptoms but substantial subclinical dysfunction. Older age at irradiation was associated with worse pulmonary outcomes. Pediatr Blood Cancer 2014;61:1277–1281. © 2014 Wiley Periodicals, Inc.

Column-store in-memory databases have received a lot of attention because of their fast query processing response times on modern multi-core machines. Among different database operations, group by/aggregate is an important and potentially costly operation. Moreover, sort-based and hash-based algorithms are the most common ways of processing group by/aggregate queries. While sort-based algorithms are used in traditional Data Base Management Systems (DBMS), hash based algorithms can be applied for faster query processing in new columnar databases. Besides, Graphical Processing Units (GPU) can be utilized as fast, high bandwidth co-processors to improve the query processing performance of columnar databases. The focus of this article is on the prototype for group by/aggregate operations that we created to exploit GPUs. We show different hash based algorithms to improve the performance of group by/aggregate operations on GPU. One of the parameters that affect the performance of the group by/aggregate algorithm is the number of groups and hashing algorithm. We show that we can get up to 7.6x improvement in kernel performance compared to a multi-core CPU implementation when we use a partitioned multi-level hash algorithm using GPU shared and global memories.

Abnormalities in pulmonary function tests (PFT) and clinical symptoms have been reported in up to one third of patients with Hodgkin lymphoma (HL) treated with irradiation. The purpose of this study is to describe the prevalence of pulmonary complications in HL patients treated using contemporary protocols.Eligible patients at Children's Hospital Los Angeles from 1999 to 2009 were identified from the radiation oncology database. Clinical features, radiographic findings, PFT, and radiation details were retrospectively ascertained.The median age at diagnosis of 65 patients with HL was 13.6 years and the median follow-up was 3.7 years. The median prescribed radiation dose was 21 Gy. The prevalence of clinical symptoms was low: chronic cough (3%), dyspnea (9.2%), and supplemental oxygen requirement (1.5%). Radiological interstitial lung changes were observed in 31% of the patients. PFT results following irradiation were available in 38 patients. Forced expiratory volume in 1 second (FEV1) and forced expiratory flow 25-75% (FEF25-75%) were decreased in 13% and 11% of patients respectively. Residual volume (RV) was elevated in 21%. Total Lung capacity (TLC) was decreased in 8%. Age at irradiation (P = 0.004), maximum lung dose (P = 0.03), and volume of lung receiving25 Gy were associated with development of adverse pulmonary outcomes on univariate analysis. On multivariate analysis, older age was associated with worse outcomes.In survivors of pediatric HL, involved field irradiation was accompanied by a low prevalence of pulmonary symptoms but substantial subclinical dysfunction. Older age at irradiation was associated with worse pulmonary outcomes.

There is limited data on pulmonary function test (PFT) abnormalities in children treated with modern irradiation techniques. PFT abnormalities have not been correlated with the dose and volume of irradiation.A retrospective chart review of PFTs and clinical outcomes in children who received radiation therapy (RT) at Children's Hospital Los Angeles between 1999 and 2009 was performed. Radiation dose distribution to normal lung tissue was calculated.Forty-nine patients had PFTs available post-RT at a median time of 2.91 years (range, 0.01-8.28) from irradiation. Sixty-seven percent of patients had at least one PFT abnormality on their last available study. The most common abnormality was obstructive lung disease (24%) followed by hyperinflation (20%). Thoracic surgery prior to RT increased the odds of an abnormal FEV1, RV/TLC, and obstructive disease. The sex of the patient, age at the time of irradiation, and time of the PFT after irradiation did not have a significant association with abnormalities. The mean lung dose, maximum lung dose, and prescribed dose of radiation were significantly associated with the development of PFT abnormalities. The odds of developing an abnormal PFT increased with increase in the minimum threshold dose (V(dose)) of radiation, mostly above V(20).PFT abnormalities are common even when modern radiation techniques are used. A significant correlation between radiation parameters and PFT abnormalities was noted.

Purpose To identify the incidence and the risk factors for pulmonary toxicity in children treated for cancer with contemporary lung irradiation. Methods and Materials We analyzed clinical features, radiographic findings, pulmonary function tests, and dosimetric parameters of children receiving irradiation to the lung fields over a 10-year period. Results We identified 109 patients (75 male patients). The median age at irradiation was 13.8 years (range, 0.04-20.9 years). The median follow-up period was 3.4 years. The median prescribed radiation dose was 21 Gy (range, 0.4-64.8 Gy). Pulmonary toxic chemotherapy included bleomycin in 58.7% of patients and cyclophosphamide in 83.5%. The following pulmonary outcomes were identified and the 5-year cumulative incidence after irradiation was determined: pneumonitis, 6%; chronic cough, 10%; pneumonia, 35%; dyspnea, 11%; supplemental oxygen requirement, 2%; radiographic interstitial lung disease, 40%; and chest wall deformity, 12%. One patient died of progressive respiratory failure. Post-irradiation pulmonary function tests available from 44 patients showed evidence of obstructive lung disease (25%), restrictive disease (11%), hyperinflation (32%), and abnormal diffusion capacity (12%). Thoracic surgery, bleomycin, age, mean lung irradiation dose (MLD), maximum lung dose, prescribed dose, and dosimetric parameters between V 22 (volume of lung exposed to a radiation dose ≥22 Gy) and V 30 (volume of lung exposed to a radiation dose ≥30 Gy) were significant for the development of adverse pulmonary outcomes on univariate analysis. MLD, maximum lung dose, and V dose (percentage of volume of lung receiving the threshold dose or greater) were highly correlated. On multivariate analysis, MLD was the sole significant predictor of adverse pulmonary outcome ( P =.01). Conclusions Significant pulmonary dysfunction occurs in children receiving lung irradiation by contemporary techniques. MLD rather than prescribed dose should be used to perform risk stratification of patients receiving lung irradiation.

The spectral subtraction method is a well-known noise reduction technique. Most implementations and variations of the basic technique advocate subtraction of the noise spectrum estimate over the entire speech spectrum. However, real world noise is mostly colored and does not affect the speech signal uniformly over the entire spectrum. In this paper, we propose a multi-band spectral subtraction approach which takes into account the fact that colored noise affects the speech spectrum differently at various frequencies. This method outperforms the standard power spectral subtraction method resulting in superior speech quality and largely reduced musical noise.