Single Low-Dose Radiation Induced Regulation of Keratinocyte Differentiation in Calcium-Induced HaCaT Cells

PubMed Central

Hahn, Hyung Jin; Youn, Hae Jeong; Cha, Hwa Jun; Kim, Karam; An, Sungkwan

2016-01-01

Background We are continually exposed to low-dose radiation (LDR) in the range 0.1 Gy from natural sources, medical devices, nuclear energy plants, and other industrial sources of ionizing radiation. There are three models for the biological mechanism of LDR: the linear no-threshold model, the hormetic model, and the threshold model. Objective We used keratinocytes as a model system to investigate the molecular genetic effects of LDR on epidermal cell differentiation. Methods To identify keratinocyte differentiation, we performed western blots using a specific antibody for involucrin, which is a precursor protein of the keratinocyte cornified envelope and a marker for keratinocyte terminal differentiation. We also performed quantitative polymerase chain reaction. We examined whether LDR induces changes in involucrin messenger RNA (mRNA) and protein levels in calcium-induced keratinocyte differentiation. Results Exposure of HaCaT cells to LDR (0.1 Gy) induced p21 expression. p21 is a key regulator that induces growth arrest and represses stemness, which accelerates keratinocyte differentiation. We correlated involucrin expression with keratinocyte differentiation, and examined the effects of LDR on involucrin levels and keratinocyte development. LDR significantly increased involucrin mRNA and protein levels during calcium-induced keratinocyte differentiation. Conclusion These studies provide new evidence for the biological role of LDR, and identify the potential to utilize LDR to regulate or induce keratinocyte differentiation. PMID:27489424

Variance Assistance Document: Land Disposal Restrictions Treatability Variances and Determinations of Equivalent Treatment

EPA Pesticide Factsheets

This document provides assistance to those seeking to submit a variance request for LDR treatability variances and determinations of equivalent treatment regarding the hazardous waste land disposal restrictions program.

Large Deployable Reflector (LDR) - A concept for an orbiting submillimeter-infrared telescope for the 1990s

NASA Technical Reports Server (NTRS)

Swanson, P. N.; Gulkis, S.; Kulper, T. B. H.; Kiya, M.

1983-01-01

The history and background of the Large Deployable Reflector (LDR) are reviewed. The results of the June 1982 Asilomar (CA) workshop are incorporated into the LDR science objectives and telescope concept. The areas where the LDR may have the greatest scientific impact are in the study of star formation and planetary systems in the own and nearby galaxies and in cosmological studies of the structure and evolution of the early universe. The observational requirements for these and other scientific studies give rise to a set of telescope functional requirements. These, in turn, are satisfied by an LDR configuration which is a Cassegrain design with a 20 m diameter, actively controlled, segmented, primary reflector, diffraction limited at a wavelength of 30 to 50 microns. Technical challenges in the LDR development include construction of high tolerance mirror segments, surface figure measurement, figure control, vibration control, pointing, cryogenics, and coherent detectors. Project status and future plans for the LDR are discussed.

Mathematical programming models for the economic design and assessment of wind energy conversion systems

NASA Astrophysics Data System (ADS)

Reinert, K. A.

The use of linear decision rules (LDR) and chance constrained programming (CCP) to optimize the performance of wind energy conversion clusters coupled to storage systems is described. Storage is modelled by LDR and output by CCP. The linear allocation rule and linear release rule prescribe the size and optimize a storage facility with a bypass. Chance constraints are introduced to explicitly treat reliability in terms of an appropriate value from an inverse cumulative distribution function. Details of deterministic programming structure and a sample problem involving a 500 kW and a 1.5 MW WECS are provided, considering an installed cost of $1/kW. Four demand patterns and three levels of reliability are analyzed for optimizing the generator choice and the storage configuration for base load and peak operating conditions. Deficiencies in ability to predict reliability and to account for serial correlations are noted in the model, which is concluded useful for narrowing WECS design options.

Large Deployable Reflector (LDR) feasibility study update

NASA Technical Reports Server (NTRS)

Alff, W. H.; Banderman, L. W.

1983-01-01

In 1982 a workshop was held to refine the science rationale for large deployable reflectors (LDR) and develop technology requirements that support the science rationale. At the end of the workshop, a set of LDR consensus systems requirements was established. The subject study was undertaken to update the initial LDR study using the new systems requirements. The study included mirror materials selection and configuration, thermal analysis, structural concept definition and analysis, dynamic control analysis and recommendations for further study. The primary emphasis was on the dynamic controls requirements and the sophistication of the controls system needed to meet LDR performance goals.

Children's Inductive Thinking during Intrinsic and Euclidean Geometrical Activities in a Computer Programming Environment.

ERIC Educational Resources Information Center

Kynigos, Chronis

1993-01-01

Used 2 12-year-old children to investigate deductive and inductive reasoning in plane geometry. A LOGO microworld was programmed to measure distances and turns relative to points on the plane. Learning environments like this may enhance formation of inductive geometrical understandings. (Contains 44 references.) (LDR)

An Analysis of Individualized Education Program Goals Selected for Learning-Disabled Students.

ERIC Educational Resources Information Center

McCormick, Paula K.; Fisher, Maurice D.

The study was designed to analyze the types and frequencies of individualized education program (IEP) goals selected for 102 elementary learning disabled students in resource rooms (LDR) and 94 learning disabled students in self-contained classrooms (LDSC) and to compare the learning disabilities teachers' assessments of progress made on the goals…

Low-Dose Radiation Promotes Dendritic Cell Migration and IL-12 Production via the ATM/NF-KappaB Pathway.

PubMed

Yu, Nan; Wang, Sinian; Song, Xiujun; Gao, Ling; Li, Wei; Yu, Huijie; Zhou, Chuanchuan; Wang, Zhenxia; Li, Fengsheng; Jiang, Qisheng

2018-04-01

For dendritic cells (DCs) to initiate an immune response, their ability to migrate and to produce interleukin-12 (IL-12) is crucial. It has been previously shown that low-dose radiation (LDR) promoted IL-12 production by DCs, resulting in increased DC activity that contributed to LDR hormesis in the immune system. However, the molecular mechanism of LDR-induced IL-12 production, as well as the effect of LDR on DC migration capacity require further elucidation. Using the JAWSII immortalized mouse dendritic cell line, we showed that in vitro X-ray irradiation (0.2 Gy) of DCs significantly increased DC migration and IL-12 production, and upregulated CCR7. The neutralizing antibody against CCR7 has been shown to abolish LDR-enhanced DC migration, demonstrating that CCR7 mediates LDR-promoting DC migration. We identified nuclear factor kappaB (NF-κB) as the central signaling pathway that mediated LDR-enhanced expression of IL-12 and CCR7 based on findings that 0.2 Gy X-ray irradiation activated NF-κB, showing increased nuclear p65 translocation and NF-κB DNA-binding activity, while an NF-κB inhibitor blocked LDR-enhanced expression of IL-12 and CCR7, as well as DC migration. Finally, we demonstrated that 0.2 Gy X-ray irradiation promoted ATM phosphorylation and reactive oxygen species generation; however, only the ATM inhibitor abolished the LDR-induced NF-κB-mediated expression of IL-12 and CCR7. Altogether, our data show that exposure to LDR resulted in a hormetic effect on DCs regarding CCR7-mediated migration and IL-12 production by activating the ATM/NF-κB pathway.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Doss, Mohan

Oxidative damage has been implicated in the pathogenesis of most aging-related diseases including neurodegenerative diseases. Antioxidant supplementation has been found to be ineffective in reducing such diseases, but increased endogenous production of antioxidants from the adaptive response due to physical and cognitive exercises (which increase oxidative metabolism and oxidative stress) has been effective in reducing some of the diseases. Low dose radiation (LDR), which increases oxidative stress and results in adaptive response of increased antioxidants, may provide an alternative method of controlling the aging-related diseases. We have studied the effect of LDR on the induction of adaptive response in ratmore » brains and the effectiveness of the LDR in reducing the oxidative damage caused by subsequent high dose radiation. We have also investigated the effect of LDR on apomorphine-induced rotations in the 6-hydroxydopamine (6-OHDA) unilaterally-lesioned rat model of Parkinson?s disease (PD). LDR was observed to initiate an adaptive response in the brain, and reduce the oxidative damage from subsequent high dose radiation exposure, confirming the effectiveness of LDR adaptive response in reducing the oxidative damage from the free radicals due to high dose radiation. LDR resulted in a slight improvement in Tyrosine hydroxylase expression on the lesioned side of substantia nigra (indicative of its protective effect on the dopaminergic neurons), and reduced the behavioral symptoms in the 6-OHDA rat model of PD. Translation of this concept to humans, if found to be applicable, may be a possible approach for controlling the progression of PD and other neurodegenerative diseases. Since any translation of the concept to humans would be hindered by the currently prevalent carcinogenic concerns regarding LDR based on the linear no-threshold (LNT) model, we have also studied the justifications for the use of the LNT model. One of the shortcomings of the LNT model is that it ignores the effects of any adaptive response of the body to the LDR. The importance of considering adaptive response becomes obvious when one considers the sharp contrast between (i) the failure of well-designed anti-angiogenesis therapies which resulted in aggressive tumors because of ignoring adaptive response and (ii) the occasional cure of untreated metastatic lesions likely due to the incidental adaptive response from the LDR exposure to parts of the body during radiation therapy of a primary tumor, known as the abscopal effect. Another shortcoming of the LNT model is that it pays exclusive attention to increase in mutations, which is not a decisive factor in the occurrence of clinical cancers, as the cause of excess cancers. On the other hand, LNT model ignores the immune system response, which plays a very important role in preventing occult cancers from becoming clinical cancers, as demonstrated by the large increase in cancers in organ transplant patients whose immune system is suppressed. There is also recent epidemiological evidence against the LNT model. A re-analysis of the latest update to the atomic bomb survivor data has shown that the data no longer support the LNT model but are consistent with the radiation hormesis hypothesis. A re-analysis of cancer incidence data of Taiwanese apartment dwellers that were exposed to LDR from contaminated building materials has also shown a reduction in cancers from the LDR. The present LDR carcinogenic concerns would preclude any human study of cancer prevention using LDR, since the study would require subjecting a large asymptomatic population to LDR. However, pilot studies of radiation hormesis in cancer patients may be more acceptable since these would require irradiation of limited numbers of patients in order to assess the effectiveness of the LDR treatments. Some of the LDR applications that may be considered for cancer patients are: LDR treatment of early stage cancers without the adverse side effects of current treatments such as radiation therapy or chemotherapy, adjuvant LDR treatment of cancer patients undergoing radiation therapy for better tumor control and reduced metastasis, and the use of LDR treatment following radiation therapy to reduce the risk of second cancers from the radiation therapy. Studies of LDR for the control of early-stage neurodegenerative diseases may also be more acceptable since currently there are no effective treatments available for controlling these diseases, and since such studies would require LDR exposure to limited parts of the brain, and the carcinogenic risk from such treatments would be very small due to the low radiation tissue-weighting factor for the brain. Success in these studies can lead to the study of LDR for preventing and controlling other aging-related diseases.« less

Low-dose radiation modulates human mesenchymal stem cell proliferation through regulating CDK and Rb.

PubMed

Yang, Lei; Liu, Ziling; Chen, Chen; Cong, Xiaofeng; Li, Zhi; Zhao, Shasha; Ren, Meng

2017-01-01

Low-dose radiation (LDR) has been known to stimulate cell proliferation. The effect of LDR on human bone marrow mesenchymal stem cells (BMSCs), however, remains to be determined. The current study, therefore, aimed to investigate the effect of LDR on human BMSC proliferation and its mechanisms. To accomplish this, human BMSCs were isolated from ribs and cultured with or without exposition to LDR (75 mGy) for 24 h. Cell proliferation was assessed by MTT assay, the cytokines secreted by the BMSCs were quantified by ELISA, and the proteins associated with cell proliferation and cell cycle were evaluated by immunoblot analysis. BMSCs isolated from human ribs were capable of differentiating into osteoblasts and adipocytes. LDR stimulated human BMSC proliferation (0.580 ± 0.106 vs 0.419 ± 0.026 on day 4, P < 0.05; 0.794 ± 0.025 vs 0.689 ± 0.047 on day 7, P < 0.05) and increased S-phase proportion. LDR significantly enhanced the production of SCF, GM-CSF, and IL-11. Moreover, BMSCs modulated T-cell proliferation, and LDR further augmented the modulatory effect of BMSCs on T-cell proliferation. Cell cycle-associated proteins, such as Rb, CDK1, and CDC25B, appeared to mediate the stimulatory effect of LDR on BMSC proliferation. The findings of the current study indicate that physical stimulants, such as LDR, could be used for the large-scale expansion of human BMSCs, and thus may be used for MSC cellular therapy in clinic.

Multiple scattering effects on the Linear Depolarization Ratio (LDR) measured during CaPE by a Ka-band air-borne radar

NASA Technical Reports Server (NTRS)

Iguchi, Toshio; Meneghini, Robert

1993-01-01

Air-borne radar measurements of thunderstorms were made as part of the CaPE (Convection and Precipitation/Electrification) experiment in Florida in July 1991. The radar has two channels, X-band (10 GHz) and Ka-band (34.5 GHz), and is capable of measuring cross-polarized returns as well as co-polarized returns. In stratiform rain, the cross-polarized components can be observed only at the bright band region and from the surface reflection. The linear depolarization ratios (LDR's) measured at X-band and Ka-band at the bright band are nearly equal. In convective rain, however, the LDR in Ka-band often exceeds the X-band LDR by several dB, and sometimes by more than 10 dB, reaching LDR values of up to -5 dB over heavy convective rain. For randomly oriented hydrometeors, such high LDR values cannot be explained by single scattering from non-spherical scattering particles alone. Because the LDR by single backscatter depends weakly on the wavelength, the difference between the Ka-band and X-band LDR's suggests that multiple scattering effects prevail in the Ka-band LDR. In order to test this inference, the magnitude of the cross-polarized component created by double scattering was calculated using the parameters of the airborne radar, which for both frequencies has beamwidths of 5.1 degrees and pulse widths of 0.5 microsecond. Uniform rain beyond the range of 3 km is assumed.

Large Deployable Reflector (LDR) system concept and technology definition study. Analysis of space station requirements for LDR

NASA Astrophysics Data System (ADS)

Agnew, Donald L.; Vinkey, Victor F.; Runge, Fritz C.

1989-04-01

A study was conducted to determine how the Large Deployable Reflector (LDR) might benefit from the use of the space station for assembly, checkout, deployment, servicing, refurbishment, and technology development. Requirements that must be met by the space station to supply benefits for a selected scenario are summarized. Quantitative and qualitative data are supplied. Space station requirements for LDR which may be utilized by other missions are identified. A technology development mission for LDR is outlined and requirements summarized. A preliminary experiment plan is included. Space Station Data Base SAA 0020 and TDM 2411 are updated.

Large Deployable Reflector (LDR) system concept and technology definition study. Analysis of space station requirements for LDR

NASA Technical Reports Server (NTRS)

Agnew, Donald L.; Vinkey, Victor F.; Runge, Fritz C.

1989-01-01

A study was conducted to determine how the Large Deployable Reflector (LDR) might benefit from the use of the space station for assembly, checkout, deployment, servicing, refurbishment, and technology development. Requirements that must be met by the space station to supply benefits for a selected scenario are summarized. Quantitative and qualitative data are supplied. Space station requirements for LDR which may be utilized by other missions are identified. A technology development mission for LDR is outlined and requirements summarized. A preliminary experiment plan is included. Space Station Data Base SAA 0020 and TDM 2411 are updated.

Low-dose radiation decreases tumor progression via the inhibition of the JAK1/STAT3 signaling axis in breast cancer cell lines

PubMed Central

Kaushik, Neha; Kim, Min-Jung; Kim, Rae-Kwon; Kumar Kaushik, Nagendra; Seong, Ki Moon; Nam, Seon-Young; Lee, Su-Jae

2017-01-01

Breast cancer is a widely distributed type of cancer in women worldwide, and tumor relapse is the major cause of breast cancer death. In breast cancers, the acquisition of metastatic ability, which is responsible for tumor relapse and poor clinical outcomes, has been linked to the acquisition of the epithelial-mesenchymal transition (EMT) program and self-renewal traits (CSCs) via various signaling pathways. These phenomena confer resistance during current therapies, thus creating a major hurdle in radiotherapy/chemotherapy. The role of very low doses of radiation (LDR) in the context of EMT has not yet to be thoroughly explored. Here, we report that a 0.1 Gy radiation dose reduces cancer progression by deactivating the JAK1/STAT3 pathway. Furthermore, LDR exposure also reduces sphere formation and inhibits the self-renewal ability of breast cancer cells, resulting in an attenuated CD44+/CD24− population. Additionally, in vivo findings support our data, providing evidence that LDR is a promising option for future treatment strategies to prevent cancer metastasis in breast cancer cases. PMID:28240233

Workshop on Technology Development Issues for the Large Deployable Reflector (LDR)

NASA Technical Reports Server (NTRS)

Nishioka, Kenji (Editor)

1986-01-01

The results of the 2nd Large Deployable Reflector (LDR) Technology Review Workshop held at Asilomar, California, March 17 to 22, 1985, are summarized. The workshop was convened to update LDR Technology status and to revise as necessary the results for the first LDR Workshop held in June 1982. There were some 100 participants representing government agencies, industry, and universities. This Workshop's goal was to assess, identify, and set priorities for the LDR technology issues based on requirements identified in the first workshop. Four high-priority technology areas were identified: (1) mirror materials and construction; (2) sensing and controls; (3) system-simulation and modeling capability; and (4) submillimeter instruments. The results of the workshop were used to provide a list of technolgy issues for the development of a technology initiatives plan for the LDR by NASA's Office of Aeronautics and Space Technology.

Low‑dose radiation‑induced apoptosis in human leukemia K562 cells through mitochondrial pathways.

PubMed

Xin, Yong; Zhang, Hai-Bin; Tang, Tian-You; Liu, Gui-Hong; Wang, Jian-She; Jiang, Guan; Zhang, Long-Zhen

2014-09-01

High‑dose total body irradiation (TBI) has an established role as preparative regimen for bone‑marrow transplantation in the treatment of chronic myelogenous leukemia (CML), but this regimen still has a relatively high rate of acute and late toxicity. Low‑dose radiation (LDR) induces apoptosis of tumor cells and has numerous beneficial effects on normal tissues, including radiation homeostasis and adaptive response. Based on the previous evidence, in the present study, K562 cells were exposed to LDR, high‑dose radiation (HDR), and LDR in combination with HDR to investigate the possible mechanism of the apoptotic effect and hypersensitivity induced by LDR. The apoptotic rate increased in all radiation groups in a time‑dependent manner. An upregulation of Bax protein expression and a downregulation of Bcl‑xl in a dose‑dependent manner in human leukemia K562 cells was observed. However, the expression of p53 protein did not change in all of the radiation cell groups. The mitochondrial membrane potential (ΔΨm) in K562 cells decreased in all of the radiation cell groups in a dose‑dependent manner. Furthermore, the decrease of ΔΨm was enhanced in the LDR/HDR group compared with that in the LDR or HDR groups. The activity of caspase‑3 was enhanced in all of the radiation groups. In the LDR/HDR group, the activity of caspase‑3 was higher than that in the HDR or LDR groups. The present study provided preliminary experimental evidence of LDR being beneficial in combination with TBI in the treatment of CML.

Mechanism-based inactivation of CYP2C9 by linderane.

PubMed

Wang, Hui; Wang, Kai; Mao, Xu; Zhang, Qingqing; Yao, Tong; Peng, Ying; Zheng, Jiang

2015-01-01

1. Linderane (LDR), a furan-containing sesquiterpenoid, is found in Lindera aggregata (Sims) Kosterm, a common traditional Chinese herbal medicine. We thoroughly studied the irreversible inhibitory effect of LDR on cytochrome P450 2C9 (CYP2C9). 2. LDR caused a time- and concentration-dependent inactivation of CYP2C9. In addition, the inactivation of CYP2C9 by LDR was NADPH-dependent and irreversible. More than 50% of CYP2C9 activity was lost after its incubation with LDR at the concentration of 10 μM for 15 min at 30 °C. The maximal rate constant for inactivation (kinact) was found to be 0.0419 min(-1), and the concentration required for half-maximal inactivation (KI) was 1.26 μM, respectively. Glutathione (GSH), catalase, and superoxide dismutase (SOD) failed to protect CYP2C9 against inactivation by LDR. Diclofenac, a substrate of CYP2C9, prevented the enzyme from inactivation produced by LDR. The estimated partition ratio of the inactivation was approximately 227. 3. Two reactive intermediates, including furanoepoxide and γ-ketoenal, might be responsible for the observed enzyme inactivation. The formation of the intermediates was verified by chemical synthesis. Multiple P450 enzymes, including CYPs 1A2, 2B6, 2C9, 2C19, 2D6, 3A4, and 3A5, were found to be involved in the metabolic activation of LDR. In conclusion, LDR was characterized as a mechanism-based inactivator of CYP2C9.

Time Course and Accumulated Risk of Severe Urinary Adverse Events After High- Versus Low-Dose-Rate Prostate Brachytherapy With or Without External Beam Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tward, Jonathan D., E-mail: Jonathan.Tward@hci.utah.edu; Jarosek, Stephanie; Chu, Haitao

Purpose: Severe urinary adverse events (UAEs) include surgical treatment of urethral stricture, urinary incontinence, and radiation cystitis. We compared the incidence of grade 3 UAEs, according to the Common Terminology Criteria for Adverse Events, after low-dose-rate (LDR) and high-dose-rate (HDR) brachytherapy, as well as after LDR plus external beam radiation therapy (EBRT) and HDR plus EBRT. Methods and Materials: Men aged >65 years with nonmetastatic prostate cancer were identified from the Surveillance, Epidemiology, and End Results–Medicare database who were treated with LDR (n=12,801), HDR (n=685), LDR plus EBRT (n=8518), or HDR plus EBRT (n=2392). The populations were balanced by propensity weighting, andmore » the Kaplan-Meier incidence of severe UAEs was compared. Propensity-weighted Cox proportional hazards models were used to compare the adjusted hazard of UAEs. These UAEs were compared with those in a cohort of men not treated for prostate cancer. Results: Median follow-up was 4.3 years. At 8 years, the propensity-weighted cumulative UAE incidence was highest after HDR plus EBRT (26.6% [95% confidence interval, 23.8%-29.7%]) and lowest after LDR (15.7% [95% confidence interval, 14.8%-16.6%]). The absolute excess risk over nontreated controls at 8 years was 1.9%, 3.8%, 8.4%, and 12.9% for LDR, HDR, LDR plus EBRT, and HDR plus EBRT, respectively. These represent numbers needed to harm of 53, 26, 12, and 8 persons, respectively. The additional risk of development of a UAE related to treatment for LDR, LDR plus EBRT, and HDR plus EBRT was greatest within the 2 years after treatment and then continued to decline over time. Beyond 4 years, the risk of development of a new severe UAE matched the baseline risk of the control population for all treatments. Conclusions: Toxicity differences were observed between LDR and HDR, but the differences did not meet statistical significance. However, combination radiation therapy (either HDR plus EBRT or LDR plus EBRT) increases the risk of severe UAEs compared with HDR alone or LDR alone. The highest increased risk of urinary toxicity occurs within the 2 years after therapy and then declines to an approximately 1% increase in incidence per year.« less

Time Course and Accumulated Risk of Severe Urinary Adverse Events After High- Versus Low-Dose-Rate Prostate Brachytherapy With or Without External Beam Radiation Therapy.

PubMed

Tward, Jonathan D; Jarosek, Stephanie; Chu, Haitao; Thorpe, Cameron; Shrieve, Dennis C; Elliott, Sean

2016-08-01

Severe urinary adverse events (UAEs) include surgical treatment of urethral stricture, urinary incontinence, and radiation cystitis. We compared the incidence of grade 3 UAEs, according to the Common Terminology Criteria for Adverse Events, after low-dose-rate (LDR) and high-dose-rate (HDR) brachytherapy, as well as after LDR plus external beam radiation therapy (EBRT) and HDR plus EBRT. Men aged >65 years with nonmetastatic prostate cancer were identified from the Surveillance, Epidemiology, and End Results-Medicare database who were treated with LDR (n=12,801), HDR (n=685), LDR plus EBRT (n=8518), or HDR plus EBRT (n=2392). The populations were balanced by propensity weighting, and the Kaplan-Meier incidence of severe UAEs was compared. Propensity-weighted Cox proportional hazards models were used to compare the adjusted hazard of UAEs. These UAEs were compared with those in a cohort of men not treated for prostate cancer. Median follow-up was 4.3 years. At 8 years, the propensity-weighted cumulative UAE incidence was highest after HDR plus EBRT (26.6% [95% confidence interval, 23.8%-29.7%]) and lowest after LDR (15.7% [95% confidence interval, 14.8%-16.6%]). The absolute excess risk over nontreated controls at 8 years was 1.9%, 3.8%, 8.4%, and 12.9% for LDR, HDR, LDR plus EBRT, and HDR plus EBRT, respectively. These represent numbers needed to harm of 53, 26, 12, and 8 persons, respectively. The additional risk of development of a UAE related to treatment for LDR, LDR plus EBRT, and HDR plus EBRT was greatest within the 2 years after treatment and then continued to decline over time. Beyond 4 years, the risk of development of a new severe UAE matched the baseline risk of the control population for all treatments. Toxicity differences were observed between LDR and HDR, but the differences did not meet statistical significance. However, combination radiation therapy (either HDR plus EBRT or LDR plus EBRT) increases the risk of severe UAEs compared with HDR alone or LDR alone. The highest increased risk of urinary toxicity occurs within the 2 years after therapy and then declines to an approximately 1% increase in incidence per year. Copyright © 2016. Published by Elsevier Inc.

Low-dose radiation pretreatment improves survival of human ceiling culture-derived proliferative adipocytes (ccdPAs) under hypoxia via HIF-1 alpha and MMP-2 induction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adachi, Naoki; Kubota, Yoshitaka, E-mail: kubota-cbu@umin.ac.jp; Kosaka, Kentarou

2015-08-07

Poor survival is a major problem of adipocyte transplantation. We previously reported that VEGF and MMPs secreted from transplanted adipocytes are essential for angiogenesis and adipogenesis. Pretreatment with low-dose (5 Gy) radiation (LDR) increased VEGF, MMP-2, and HIF-1 alpha mRNA expression in human ceiling culture-derived proliferative adipocytes (hccdPAs). Gene expression after LDR differed between adipose-derived stem cells (hASCs) and hccdPAs. Pretreatment with LDR improved the survival of hccdPAs under hypoxia, which is inevitable in the early stages after transplantation. Upregulation of VEGF and MMP-2 after LDR in hccdPAs is mediated by HIF-1 alpha expression. Our results suggest that pretreatment with LDRmore » may improve adipocyte graft survival in a clinical setting through upregulation of VEGF and MMP-2 via HIF-1 alpha. - Highlights: • Ceiling culture-derived proliferative adipocytes (ccdPAs) react to radiation. • Low-dose radiation (LDR) pretreatment improves survival of ccdPAs under hypoxia. • Gene expression after LDR differs between ccdPAs and adipose-derived stem cells. • LDR-induced increase in MMP-2 and VEGF is dependent on HIF-1 alpha induction. • LDR pretreatment may improve the adipocyte graft survival rate in clinical settings.« less

LDR vs. HDR brachytherapy for localized prostate cancer: the view from radiobiological models.

PubMed

King, Christopher R

2002-01-01

Permanent LDR brachytherapy and temporary HDR brachytherapy are competitive techniques for clinically localized prostate radiotherapy. Although a randomized trial will likely never be conducted comparing these two forms of brachytherapy, a comparative radiobiological modeling analysis proves useful in understanding some of their intrinsic differences, several of which could be exploited to improve outcomes. Radiobiological models based upon the linear quadratic equations are presented for fractionated external beam, fractionated (192)Ir HDR brachytherapy, and (125)I and (103)Pd LDR brachytherapy. These models incorporate the dose heterogeneities present in brachytherapy based upon patient-derived dose volume histograms (DVH) as well as tumor doubling times and repair kinetics. Radiobiological parameters are normalized to correspond to three accepted clinical risk factors based upon T-stage, PSA, and Gleason score to compare models with clinical series. Tumor control probabilities (TCP) for LDR and HDR brachytherapy (as monotherapy or combined with external beam) are compared with clinical bNED survival rates. Predictions are made for dose escalation with HDR brachytherapy regimens. Model predictions for dose escalation with external beam agree with clinical data and validate the models and their underlying assumptions. Both LDR and HDR brachytherapy achieve superior tumor control when compared with external beam at conventional doses (<70 Gy), but similar to results from dose escalation series. LDR brachytherapy as boost achieves superior tumor control than when used as monotherapy. Stage for stage, both LDR and current HDR regimens achieve similar tumor control rates, in agreement with current clinical data. HDR monotherapy with large-dose fraction sizes might achieve superior tumor control compared with LDR, especially if prostate cancer possesses a high sensitivity to dose fractionation (i.e., if the alpha/beta ratio is low). Radiobiological models support the current clinical evidence for equivalent outcomes in localized prostate cancer with either LDR or HDR brachytherapy using current dose regimens. However, HDR brachytherapy dose escalation regimens might be able to achieve higher biologically effective doses of irradiation in comparison to LDR, and hence improved outcomes. This advantage over LDR would be amplified should prostate cancer possess a high sensitivity to dose fractionation (i.e., a low alpha/beta ratio) as the current evidence suggests.

Brachytherapy Boost Utilization and Survival in Unfavorable-risk Prostate Cancer.

PubMed

Johnson, Skyler B; Lester-Coll, Nataniel H; Kelly, Jacqueline R; Kann, Benjamin H; Yu, James B; Nath, Sameer K

2017-11-01

There are limited comparative survival data for prostate cancer (PCa) patients managed with a low-dose rate brachytherapy (LDR-B) boost and dose-escalated external-beam radiotherapy (DE-EBRT) alone. To compare overall survival (OS) for men with unfavorable PCa between LDR-B and DE-EBRT groups. Using the National Cancer Data Base, we identified men with unfavorable PCa treated between 2004 and 2012 with androgen suppression (AS) and either EBRT followed by LDR-B or DE-EBRT (75.6-86.4Gy). Treatment selection was evaluated using logistic regression and annual percentage proportions. OS was analyzed using the Kaplan-Meier method, log-rank test, Cox proportional hazards, and propensity score matching. We identified 25038 men between 2004 and 2012, during which LDR-B boost utilization decreased from 29% to 14%. LDR-B was associated with better OS on univariate (7-yr OS: 82% vs 73%; p<0.001) and multivariate analyses (hazard ratio [HR] 0.70, 95% confidence interval [CI] 0.64-0.77). Propensity score matching verified an OS benefit associated with LDR-B boost (HR 0.74, 95% CI 0.66-0.89). The OS benefit of LDR-B boost persisted when limited to men aged <60 yr with no comorbidities. On subset analysis, there was no interaction between treatment and age, risk group, or radiation dose. Limitations include the retrospective design, nonrandomized selection bias, and the absence of treatment toxicity, hormone duration, and cancer-specific outcomes. Between 2004 and 2012, LDR-B boost utilization declined and was associated with better OS compared to DE-EBRT alone. LDR-B boost is probably the ideal treatment option for men with unfavorable PCa, pending long-term results of randomized trials. We compared radiotherapy utilization and survival for prostate cancer (PCa) patients using a national database. We found that low-dose rate brachytherapy (LDR-B) boost, a method being used less frequently, was associated with better overall survival when compared to dose-escalated external-beam radiotherapy alone for men with unfavorable PCa. Randomized trials are needed to confirm that LDR-B boost is the ideal treatment. Copyright © 2017 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Biological equivalence between LDR and PDR in cervical cancer: multifactor analysis using the linear-quadratic model.

PubMed

Couto, José Guilherme; Bravo, Isabel; Pirraco, Rui

2011-09-01

The purpose of this work was the biological comparison between Low Dose Rate (LDR) and Pulsed Dose Rate (PDR) in cervical cancer regarding the discontinuation of the afterloading system used for the LDR treatments at our Institution since December 2009. In the first phase we studied the influence of the pulse dose and the pulse time in the biological equivalence between LDR and PDR treatments using the Linear Quadratic Model (LQM). In the second phase, the equivalent dose in 2 Gy/fraction (EQD(2)) for the tumor, rectum and bladder in treatments performed with both techniques was evaluated and statistically compared. All evaluated patients had stage IIB cervical cancer and were treated with External Beam Radiotherapy (EBRT) plus two Brachytherapy (BT) applications. Data were collected from 48 patients (26 patients treated with LDR and 22 patients with PDR). In the analyses of the influence of PDR parameters in the biological equivalence between LDR and PDR treatments (Phase 1), it was calculated that if the pulse dose in PDR was kept equal to the LDR dose rate, a small the-rapeutic loss was expected. If the pulse dose was decreased, the therapeutic window became larger, but a correction in the prescribed dose was necessary. In PDR schemes with 1 hour interval between pulses, the pulse time did not influence significantly the equivalent dose. In the comparison between the groups treated with LDR and PDR (Phase 2) we concluded that they were not equivalent, because in the PDR group the total EQD(2) for the tumor, rectum and bladder was smaller than in the LDR group; the LQM estimated that a correction in the prescribed dose of 6% to 10% was ne-cessary to avoid therapeutic loss. A correction in the prescribed dose was necessary; this correction should be achieved by calculating the PDR dose equivalent to the desired LDR total dose.

Biological equivalence between LDR and PDR in cervical cancer: multifactor analysis using the linear-quadratic model

PubMed Central

Bravo, Isabel; Pirraco, Rui

2011-01-01

Purpose The purpose of this work was the biological comparison between Low Dose Rate (LDR) and Pulsed Dose Rate (PDR) in cervical cancer regarding the discontinuation of the afterloading system used for the LDR treatments at our Institution since December 2009. Material and methods In the first phase we studied the influence of the pulse dose and the pulse time in the biological equivalence between LDR and PDR treatments using the Linear Quadratic Model (LQM). In the second phase, the equivalent dose in 2 Gy/fraction (EQD2) for the tumor, rectum and bladder in treatments performed with both techniques was evaluated and statistically compared. All evaluated patients had stage IIB cervical cancer and were treated with External Beam Radiotherapy (EBRT) plus two Brachytherapy (BT) applications. Data were collected from 48 patients (26 patients treated with LDR and 22 patients with PDR). Results In the analyses of the influence of PDR parameters in the biological equivalence between LDR and PDR treatments (Phase 1), it was calculated that if the pulse dose in PDR was kept equal to the LDR dose rate, a small the-rapeutic loss was expected. If the pulse dose was decreased, the therapeutic window became larger, but a correction in the prescribed dose was necessary. In PDR schemes with 1 hour interval between pulses, the pulse time did not influence significantly the equivalent dose. In the comparison between the groups treated with LDR and PDR (Phase 2) we concluded that they were not equivalent, because in the PDR group the total EQD2 for the tumor, rectum and bladder was smaller than in the LDR group; the LQM estimated that a correction in the prescribed dose of 6% to 10% was ne-cessary to avoid therapeutic loss. Conclusions A correction in the prescribed dose was necessary; this correction should be achieved by calculating the PDR dose equivalent to the desired LDR total dose. PMID:23346123

Guidebook: Quality Assurance/Quality Control Procedures for Submission of Data for the Land Disposal Restrictions (LDR) Program

EPA Pesticide Factsheets

This document explains how to generate data which characterizes the performance of hazardous waste treatment systems in terms of the composition of treated hazardous waste streams plus treatment system operation and design.

LDR system concepts and technology

NASA Technical Reports Server (NTRS)

Pittman, B.

1985-01-01

The Large Deployable Reflector is a 20 meter diameter infrared/submillimeter telescope planned for the late 1990's. The Astronomy Survey Committee of the National Academy of Sciences (Field Committee) recommended LDR as one of the two space based observatories that should start development in the 80's. LDR's large aperture will give it unequaled resolution in the wavelength range from 30 to 1000 microns. To meet LDR performance goals will call for advances in several technology disciplines including: optics, controls, thermal control, detectors, cryogenic cooling, and large space structures.

Report of the Asilomar 3 LDR Workshop

NASA Technical Reports Server (NTRS)

Mahoney, M. J. (Editor)

1988-01-01

The conclusions and recommendations of the workshop held to study technology development issues critical to the Large Deployable Reflector (LDR) are summarized. LDR is to be a dedicated, orbiting, astronomical observatory, operating at wavelengths from 30 to 1000 microns, a spectral region where the Earth's atmosphere is almost completely opaque. Because it will have a large, segmented, passively cooled aperture, LDR addresses a wide range of technology areas. These include lightweight, low cost, structural composite reflector panels, primary support structures, wavefront sensing and adaptive optics, thermal background management, and integrated vibration and pointing control systems. The science objectives for LDR present instrument development challenges for coherent and direct arrayed detectors which can operate effectively at far infrared and submillimeter wavelengths, and for sub-Kelvin cryogenic systems.

Large Deployable Reflector (LDR) Requirements for Space Station Accommodations

NASA Technical Reports Server (NTRS)

Crowe, D. A.; Clayton, M. J.; Runge, F. C.

1985-01-01

Top level requirements for assembly and integration of the Large Deployable Reflector (LDR) Observatory at the Space Station are examined. Concepts are currently under study for LDR which will provide a sequel to the Infrared Astronomy Satellite and the Space Infrared Telescope Facility. LDR will provide a spectacular capability over a very broad spectral range. The Space Station will provide an essential facility for the initial assembly and check out of LDR, as well as a necessary base for refurbishment, repair and modification. By providing a manned platform, the Space Station will remove the time constraint on assembly associated with use of the Shuttle alone. Personnel safety during necessary EVA is enhanced by the presence of the manned facility.

Large Deployable Reflector (LDR) requirements for space station accommodations

NASA Astrophysics Data System (ADS)

Crowe, D. A.; Clayton, M. J.; Runge, F. C.

1985-04-01

Top level requirements for assembly and integration of the Large Deployable Reflector (LDR) Observatory at the Space Station are examined. Concepts are currently under study for LDR which will provide a sequel to the Infrared Astronomy Satellite and the Space Infrared Telescope Facility. LDR will provide a spectacular capability over a very broad spectral range. The Space Station will provide an essential facility for the initial assembly and check out of LDR, as well as a necessary base for refurbishment, repair and modification. By providing a manned platform, the Space Station will remove the time constraint on assembly associated with use of the Shuttle alone. Personnel safety during necessary EVA is enhanced by the presence of the manned facility.

WE-E-BRD-01: HDR Brachytherapy I: Overview of Clinical Application and QA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Libby, B; Showalter, T

2014-06-15

With the increased usage of high dose rate (HDR) brachytherapy and the introduction of dedicated image guided brachytherapy suites, it is necessary to review the processes and procedures associated with safely delivering these treatments in the expedited time scales that dedicated treatment suites afford. The speakers will present the clinical aspects of switching from LDR to HDR treatments, including guidelines for patient selection, and the clinical outcomes comparing LDR to HDR. The speakers will also discuss the HDR treatment process itself, because the shortened clinical timeline involved with a streamlined scan/plan/treat workflow can introduce other issues. Safety and QA aspectsmore » involved with the streamlined process, including increased personnel required for parallel tasks, and possible interfering tasks causing delays in patient treatments will also be discussed. Learning Objectives: To understand the clinical aspects of HDR Brachytherapy, including common clinical indications, patient selection, and the evolving evidence in support of this therapeutic modality To review the current prominent clinical trials for HDR brachytherapy To interpret the established guidelines for HDR brachytherapy quality assurance for implementation into practical clinical settings. To introduce the basic requirements for image guided brachytherapy.« less

The Large Deployable Reflector (LDR) report of the Science Coordination Group

NASA Technical Reports Server (NTRS)

1986-01-01

The Large Deployable Reflector (LDR) is a telescope designed to carry out high-angular resolution, high-sensitivity observations at far-infrared and submillimeter wavelengths. The scientific rationale for the LDR is discussed in light of the recent Infrared Astronomical Satellite (IRAS) and Kuiper Airborne Observatory (KAO) results and the several new ground-based observatories planned for the late 1980s. The importance of high sensitivity and high angular resolution observations from space in the submillimeter region is stressed. The scientific and technical problems of using the LDR in a light bucket mode at approx. less than 5 microns and in designing the LDR as an unfilled aperture with subarcsecond resolution are also discussed. The need for an aperture as large as 20 m is established, along with the requirements of beam-shape stability, spatial chopping, thermal control, and surface figure stability. The instrument complement required to cover the wavelength-spectral resolution region of interest to the LDR is defined.

Gamma Low-Dose-Rate Ionizing Radiation Stimulates Adaptive Functional and Molecular Response in Human Aortic Endothelial Cells in a Threshold-, Dose-, and Dose Rate–Dependent Manner

PubMed Central

Vieira Dias, Juliana; Gloaguen, Celine; Kereselidze, Dimitri; Manens, Line; Tack, Karine; Ebrahimian, Teni G

2018-01-01

A central question in radiation protection research is whether low-dose and low-dose-rate (LDR) exposures to ionizing radiation play a role in progression of cardiovascular disease. The response of endothelial cells to different LDR exposures may help estimate risk of cardiovascular disease by providing the biological mechanism involved. We investigated the effect of chronic LDR radiation on functional and molecular responses of human aorta endothelial cells (HAoECs). Human aorta endothelial cells were continuously irradiated at LDR (6 mGy/h) for 15 days and analyzed at time points when the cumulative dose reached 0.05, 0.5, 1.0, and 2.0 Gy. The same doses were administered acutely at high-dose rate (HDR; 1 Gy/min). The threshold for the loss of angiogenic capacity for both LDR and HDR radiations was between 0.5 and 1.0 Gy. At 2.0 Gy, angiogenic capacity returned to normal only for HAoEC exposed to LDR radiation, associated with increased expression of antioxidant and anti-inflammatory genes. Pre-LDR, but not pre-HDR, radiation, followed by a single acute 2.0 Gy challenge dose sustained the expression of antioxidant and anti-inflammatory genes and stimulated angiogenesis. Our results suggest that dose rate is important in cellular response and that a radioadaptive response is involved for a 2.0 Gy dose at LDR. PMID:29531508

Gamma Low-Dose-Rate Ionizing Radiation Stimulates Adaptive Functional and Molecular Response in Human Aortic Endothelial Cells in a Threshold-, Dose-, and Dose Rate-Dependent Manner.

PubMed

Vieira Dias, Juliana; Gloaguen, Celine; Kereselidze, Dimitri; Manens, Line; Tack, Karine; Ebrahimian, Teni G

2018-01-01

A central question in radiation protection research is whether low-dose and low-dose-rate (LDR) exposures to ionizing radiation play a role in progression of cardiovascular disease. The response of endothelial cells to different LDR exposures may help estimate risk of cardiovascular disease by providing the biological mechanism involved. We investigated the effect of chronic LDR radiation on functional and molecular responses of human aorta endothelial cells (HAoECs). Human aorta endothelial cells were continuously irradiated at LDR (6 mGy/h) for 15 days and analyzed at time points when the cumulative dose reached 0.05, 0.5, 1.0, and 2.0 Gy. The same doses were administered acutely at high-dose rate (HDR; 1 Gy/min). The threshold for the loss of angiogenic capacity for both LDR and HDR radiations was between 0.5 and 1.0 Gy. At 2.0 Gy, angiogenic capacity returned to normal only for HAoEC exposed to LDR radiation, associated with increased expression of antioxidant and anti-inflammatory genes. Pre-LDR, but not pre-HDR, radiation, followed by a single acute 2.0 Gy challenge dose sustained the expression of antioxidant and anti-inflammatory genes and stimulated angiogenesis. Our results suggest that dose rate is important in cellular response and that a radioadaptive response is involved for a 2.0 Gy dose at LDR.

40 CFR Appendix Viii to Part 268 - LDR Effective Dates of Injected Prohibited Hazardous Wastes

Code of Federal Regulations, 2014 CFR

2014-07-01

... Prohibited Hazardous Wastes VIII Appendix VIII to Part 268 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt. 268, App. VIII Appendix VIII to Part 268—LDR Effective Dates of Injected Prohibited Hazardous Wastes National Capacity LDR...

40 CFR Appendix Viii to Part 268 - LDR Effective Dates of Injected Prohibited Hazardous Wastes

Code of Federal Regulations, 2012 CFR

2012-07-01

... Prohibited Hazardous Wastes VIII Appendix VIII to Part 268 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt. 268, App. VIII Appendix VIII to Part 268—LDR Effective Dates of Injected Prohibited Hazardous Wastes National Capacity LDR...

40 CFR Appendix Viii to Part 268 - LDR Effective Dates of Injected Prohibited Hazardous Wastes

Code of Federal Regulations, 2011 CFR

2011-07-01

... Prohibited Hazardous Wastes VIII Appendix VIII to Part 268 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt. 268, App. VIII Appendix VIII to Part 268—LDR Effective Dates of Injected Prohibited Hazardous Wastes National Capacity LDR...

40 CFR Appendix Viii to Part 268 - LDR Effective Dates of Injected Prohibited Hazardous Wastes

Code of Federal Regulations, 2013 CFR

2013-07-01

... Prohibited Hazardous Wastes VIII Appendix VIII to Part 268 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt. 268, App. VIII Appendix VIII to Part 268—LDR Effective Dates of Injected Prohibited Hazardous Wastes National Capacity LDR...

Low-dose γ-radiation inhibits IL-1β-induced dedifferentiation and inflammation of articular chondrocytes via blockage of catenin signaling

PubMed Central

Hong, Eun-Hee; Song, Jie-Young; Lee, Su-Jae; Park, In-Chul; Um, Hong-Duck; Park, Jong Kuk; Lee, Kee-Ho; Nam, Seon Young; Hwang, Sang-Gu

2014-01-01

Although low-dose radiation (LDR) regulates a wide range of biological processes, limited information is available on the effects of LDR on the chondrocyte phenotype. Here, we found that LDR, at doses of 0.5–2 centiGray (cGy), inhibited interleukin (IL)-1β-induced chondrocyte destruction without causing side effects, such as cell death and senescence. IL-1β treatment induced an increase in the expression of α-, β-, and γ-catenin proteins in chondrocytes via Akt signaling, thereby promoting dedifferentiation through catenin-dependent suppression of Sox-9 transcription factor expression and induction of inflammation through activation of the NF-κB pathway. Notably, LDR blocked cartilage disorders by inhibiting IL-1β-induced catenin signaling and subsequent catenin-dependent suppression of the Sox-9 pathway and activation of the NF-κB pathway, without directly altering catenin expression. LDR also inhibited chondrocyte destruction through the catenin pathway induced by epidermal growth factor, phorbol 12-myristate 13-acetate, and retinoic acid. Collectively, these results identify the molecular mechanisms by which LDR suppresses pathophysiological processes and establish LDR as a potentially valuable therapeutic tool for patients with cytokine- or soluble factors-mediated cartilage disorders. PMID:24604706

Low-dose radiation modifies skin response to acute gamma-rays and protons.

PubMed

Mao, Xiao Wen; Pecaut, Michael J; Cao, Jeffrey D; Moldovan, Maria; Gridley, Daila S

2013-01-01

The goal of the present study was to obtain pilot data on the effects of protracted low-dose/low-dose-rate (LDR) γ-rays on the skin, both with and without acute gamma or proton irradiation (IR). Six groups of C57BL/6 mice were examined: a) 0 Gy control, b) LDR, c) Gamma, d) LDR+Gamma, e) Proton, and f) LDR+Proton. LDR radiation was delivered to a total dose of 0.01 Gy (0.03 cGy/h), whereas the Gamma and Proton groups received 2 Gy (0.9 Gy/min and 1.0 Gy/min, respectively). Assays were performed 56 days after exposure. Skin samples from all irradiated groups had activated caspase-3, indicative of apoptosis. The significant (p<0.05) increases in immunoreactivity in the Gamma and Proton groups were not present when LDR pre-exposure was included. However, the terminal deoxynucleotidyl transferase dUTP nick-end labeling assay for DNA fragmentation and histological examination of hematoxylin and eosin-stained sections revealed no significant differences among groups, regardless of radiation regimen. The data demonstrate that caspase-3 activation initially triggered by both forms of acute radiation was greatly elevated in the skin nearly two months after whole-body exposure. In addition, LDR γ-ray priming ameliorated this response.

Liquid droplet radiator development status

NASA Technical Reports Server (NTRS)

White, K. Alan, III

1987-01-01

Development of the Liquid Droplet Radiator (LDR) is described. Significant published results of previous investigators are presented, and work currently in progress is discussed. Several proposed LDR configurations are described, and the rectangular and triangular configurations currently of most interest are examined. Development of the droplet generator, collector, and auxiliary components are discussed. Radiative performance of a droplet sheet is considered, and experimental results are seen to be in very good agreement with analytical predictions. The collision of droplets in the droplet sheet, the charging of droplets by the space plasma, and the effect of atmospheric drag on the droplet sheet are shown to be of little consequence, or can be minimized by proper design. The LDR is seen to be less susceptible than conventional technology to the effects of micrometeoroids or hostile threats. The identification of working fluids which are stable in the orbital environments of interest is also made. Methods for reducing spacecraft contamination from an LDR to an acceptable level are discussed. Preliminary results of microgravity testing of the droplet generator are presented. Possible future NASA and Air Force missions enhanced or enabled by a LDR are also discussed. System studies indicate that the LDR is potentially less massive than heat pipe radiators. Planned microgravity testing aboard the Shuttle or space station is seen to be a logical next step in LDR development.

Dosimetric and radiobiological comparison of volumetric modulated arc therapy, high-dose rate brachytherapy, and low-dose rate permanent seeds implant for localized prostate cancer.

PubMed

Yang, Ruijie; Zhao, Nan; Liao, Anyan; Wang, Hao; Qu, Ang

2016-01-01

To investigate the dosimetric and radiobiological differences among volumetric modulated arc therapy (VMAT), high-dose rate (HDR) brachytherapy, and low-dose rate (LDR) permanent seeds implant for localized prostate cancer. A total of 10 patients with localized prostate cancer were selected for this study. VMAT, HDR brachytherapy, and LDR permanent seeds implant plans were created for each patient. For VMAT, planning target volume (PTV) was defined as the clinical target volume plus a margin of 5mm. Rectum, bladder, urethra, and femoral heads were considered as organs at risk. A 78Gy in 39 fractions were prescribed for PTV. For HDR and LDR plans, the dose prescription was D90 of 34Gy in 8.5Gy per fraction, and 145Gy to clinical target volume, respectively. The dose and dose volume parameters were evaluated for target, organs at risk, and normal tissue. Physical dose was converted to dose based on 2-Gy fractions (equivalent dose in 2Gy per fraction, EQD2) for comparison of 3 techniques. HDR and LDR significantly reduced the dose to rectum and bladder compared with VMAT. The Dmean (EQD2) of rectum decreased 22.36Gy in HDR and 17.01Gy in LDR from 30.24Gy in VMAT, respectively. The Dmean (EQD2) of bladder decreased 6.91Gy in HDR and 2.53Gy in LDR from 13.46Gy in VMAT. For the femoral heads and normal tissue, the mean doses were also significantly reduced in both HDR and LDR compared with VMAT. For the urethra, the mean dose (EQD2) was 80.26, 70.23, and 104.91Gy in VMAT, HDR, and LDR brachytherapy, respectively. For localized prostate cancer, both HDR and LDR brachytherapy were clearly superior in the sparing of rectum, bladder, femoral heads, and normal tissue compared with VMAT. HDR provided the advantage in sparing of urethra compared with VMAT and LDR. Copyright © 2016 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

Dosimetric and radiobiological comparison of volumetric modulated arc therapy, high-dose rate brachytherapy, and low-dose rate permanent seeds implant for localized prostate cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Ruijie, E-mail: ruijyang@yahoo.com; Zhao, Nan; Liao, Anyan

To investigate the dosimetric and radiobiological differences among volumetric modulated arc therapy (VMAT), high-dose rate (HDR) brachytherapy, and low-dose rate (LDR) permanent seeds implant for localized prostate cancer. A total of 10 patients with localized prostate cancer were selected for this study. VMAT, HDR brachytherapy, and LDR permanent seeds implant plans were created for each patient. For VMAT, planning target volume (PTV) was defined as the clinical target volume plus a margin of 5 mm. Rectum, bladder, urethra, and femoral heads were considered as organs at risk. A 78 Gy in 39 fractions were prescribed for PTV. For HDR andmore » LDR plans, the dose prescription was D{sub 90} of 34 Gy in 8.5 Gy per fraction, and 145 Gy to clinical target volume, respectively. The dose and dose volume parameters were evaluated for target, organs at risk, and normal tissue. Physical dose was converted to dose based on 2-Gy fractions (equivalent dose in 2 Gy per fraction, EQD{sub 2}) for comparison of 3 techniques. HDR and LDR significantly reduced the dose to rectum and bladder compared with VMAT. The D{sub mean} (EQD{sub 2}) of rectum decreased 22.36 Gy in HDR and 17.01 Gy in LDR from 30.24 Gy in VMAT, respectively. The D{sub mean} (EQD{sub 2}) of bladder decreased 6.91 Gy in HDR and 2.53 Gy in LDR from 13.46 Gy in VMAT. For the femoral heads and normal tissue, the mean doses were also significantly reduced in both HDR and LDR compared with VMAT. For the urethra, the mean dose (EQD{sub 2}) was 80.26, 70.23, and 104.91 Gy in VMAT, HDR, and LDR brachytherapy, respectively. For localized prostate cancer, both HDR and LDR brachytherapy were clearly superior in the sparing of rectum, bladder, femoral heads, and normal tissue compared with VMAT. HDR provided the advantage in sparing of urethra compared with VMAT and LDR.« less

Different effects of blue and red light-emitting diodes on antioxidant responses in the liver and ovary of zebrafish Danio rerio.

PubMed

Yuan, Shuang-Shuang; Xu, Huan-Zhi; Liu, Li-Qin; Zheng, Jia-Lang

2017-04-01

The present study assessed the effects of a white fluorescent bulb (the control) and two different light-emitting diodes (blue LEDs, LDB; red, LDR) on growth, morphology, and oxidative stress in the liver and ovary of zebrafish for 5 weeks. Growth maintained relatively constant under LDB condition, but was reduced under LDR condition. In the liver, hepatosomatic index (HSI) and protein carbonylation (PC) increased under LDR condition, whereas lipid peroxidation (LPO) declined and HSI remained unchanged under LDB condition. The decrease in oxidative damage by LDB could be attributed to the up-regulated levels of mRNA, protein, and activity of Cu/Zn-SOD and CAT. A failure to activate the activity of both enzymes may result in the enhanced PC levels under LDR condition, though both genes were up-regulated at transcriptional and translational levels. In the ovary, although gonadosomatic index sharply increased under LDR condition, LPO and PC dramatically accumulated. The increase in oxidative damage by LDR might result from the down-regulated levels of protein and activity of Cu/Zn-SOD and CAT, though both genes were up-regulated at a transcriptional level. Furthermore, a sharp increase in expression of transcription factor Nrf2 that targets antioxidant genes was observed in the liver but not in the ovary under LDB and LDR conditions. In conclusion, our data demonstrated a positive effect of LDB and negative effect of LDR on fish antioxidant defenses, emphasizing the potentials of LDB as an effective light source in fish farming.

Selected Linguistic and Perceptual Abilities of Empirically Derived Subgroups of Learning Disabled Readers.

ERIC Educational Resources Information Center

Lyon, Reid; And Others

1981-01-01

Linguistic and perceptual tests were administered to learning disabled readers (LDR) and normal readers (NR). Results found six LDR subgroups all significantly different. Differences were found among the six LDR subgroups on measures of oral reading, reading comprehension, and spelling skills, but not on family history and developmental…

Would You Do It Again? Relationship Skills Gained in a Long-Distance Relationship

ERIC Educational Resources Information Center

Mietzner, Sara; Lin Li-Wen

2005-01-01

This study examined if experienced long-distance relationship (LDR) participants would be willing to be involved in a LDR again. In addition, although positive and negative outcomes have been reported in LDRs research, very little research investigated relationship skills gained during a LDR. Students in a Midwestern university completed…

Low-Dose Radiation Induces Cell Proliferation in Human Embryonic Lung Fibroblasts but not in Lung Cancer Cells: Importance of ERK1/2 and AKT Signaling Pathways.

PubMed

Liang, Xinyue; Gu, Junlian; Yu, Dehai; Wang, Guanjun; Zhou, Lei; Zhang, Xiaoying; Zhao, Yuguang; Chen, Xiao; Zheng, Shirong; Liu, Qiang; Cai, Lu; Cui, Jiuwei; Li, Wei

2016-01-01

Hormesis and adaptive responses are 2 important biological effects of low-dose ionizing radiation (LDR). In normal tissue, LDR induces hormesis as evinced by increased cell proliferation; however, whether LDR also increases tumor cell proliferation needs to be investigated. In this study, cell proliferation was assayed by total cell numbers and the Cell Counting Kit 8 assay. Mitogen-activated protein kinases (MAPK)/extracellular signal-regulated kinase (ERK) and phosphatidylinositol 3' -kinase(PI3K)-Akt (PI3K/AKT) phosphorylation were determined by Western blot analysis. Human embryonic lung fibroblast 2BS and lung cancer NCI-H446 cell lines were irradiated with LDR at different doses (20-100 mGy). In response to 20 to 75 mGy X-rays, cell proliferation was significantly increased in 2BS but not in NCI-H446 cells. In 2BS cells, LDR at 20 to 75 mGy also stimulated phosphorylation of MAPK/ERK pathway proteins including ERK, MEK, and Raf and of the PI3K/AKT pathway protein AKT. To test whether ERK1/2 and AKT pathway activation was involved in the stimulation of cell proliferation in 2BS cells, the MAPK/ERK and PI3K/AKT pathways were inhibited using their specific inhibitors, U0126 and LY294002. U0126 decreased the phosphorylation of ERK1/2, and LY294002 decreased the phosphorylation of AKT; each could significantly inhibit LDR-induced 2BS cell proliferation. However, LDR did not stimulate these kinases, and kinase inhibitors also did not affect cell proliferation in the NCI-H446 cells. These results suggest that LDR stimulates cell proliferation via the activation of both MAPK/ERK and PI3K/AKT signaling pathways in 2BS but not in NCI-H446 cells. This finding implies the potential for applying LDR to protect normal tissues from radiotherapy without diminishing the efficacy of tumor therapy.

Phase III randomized trial comparing LDR and HDR brachytherapy in treatment of cervical carcinoma.

PubMed

Lertsanguansinchai, Prasert; Lertbutsayanukul, Chawalit; Shotelersuk, Kanjana; Khorprasert, Chonlakiet; Rojpornpradit, Prayuth; Chottetanaprasith, Taywin; Srisuthep, Apiradee; Suriyapee, Sivalee; Jumpangern, Chotika; Tresukosol, Damrong; Charoonsantikul, Chulee

2004-08-01

Intracavitary brachytherapy plays an important role in the treatment of cervical carcinoma. Previous results have shown controversy between the effect of dose rate on tumor control and the occurrence of complications. We performed a prospective randomized clinical trial to compare the clinical outcomes between low-dose-rate (LDR) and high-dose-rate (HDR) intracavitary brachytherapy for treatment of invasive uterine cervical carcinoma. A total of 237 patients with previously untreated invasive carcinoma of the uterine cervix treated at King Chulalongkorn Memorial Hospital were randomized between June 1995 and December 2001. Excluding ineligible, incomplete treatment, and incomplete data patients, 109 and 112 patients were in the LDR and HDR groups, respectively. All patients were treated with external beam radiotherapy and LDR or HDR intracavitary brachytherapy using the Chulalongkorn treatment schedule. The median follow-up for the LDR and HDR groups was 40.2 and 37.2 months, respectively. The actuarial 3-year overall and relapse-free survival rate for all patients was 69.6% and 70%, respectively. The 3-year overall survival rate in the LDR and HDR groups was 70.9% and 68.4% (p = 0.75) and the 3-year pelvic control rate was 89.1% and 86.4% (p = 0.51), respectively. The 3-year relapse-free survival rate in both groups was 69.9% (p = 0.35). Most recurrences were distant metastases, especially in Stage IIB and IIIB patients. Grade 3 and 4 complications were found in 2.8% and 7.1% of the LDR and HDR groups (p = 0.23). Comparable outcomes were demonstrated between LDR and HDR intracavitary brachytherapy. Concerning patient convenience, the lower number of medical personnel needed, and decreased radiation to health care workers, HDR intracavitary brachytherapy is an alternative to conventional LDR brachytherapy. The high number of distant failure suggests that other modalities such as systemic concurrent or adjuvant chemotherapy might lower this high recurrence, especially in Stage IIB and IIIB.

Low-Dose Radiation Induces Cell Proliferation in Human Embryonic Lung Fibroblasts but not in Lung Cancer Cells

PubMed Central

Liang, Xinyue; Gu, Junlian; Yu, Dehai; Wang, Guanjun; Zhou, Lei; Zhang, Xiaoying; Zhao, Yuguang; Chen, Xiao; Zheng, Shirong; Liu, Qiang; Cai, Lu

2016-01-01

Hormesis and adaptive responses are 2 important biological effects of low-dose ionizing radiation (LDR). In normal tissue, LDR induces hormesis as evinced by increased cell proliferation; however, whether LDR also increases tumor cell proliferation needs to be investigated. In this study, cell proliferation was assayed by total cell numbers and the Cell Counting Kit 8 assay. Mitogen-activated protein kinases (MAPK)/extracellular signal-regulated kinase (ERK) and phosphatidylinositol 3′ -kinase(PI3K)-Akt (PI3K/AKT) phosphorylation were determined by Western blot analysis. Human embryonic lung fibroblast 2BS and lung cancer NCI-H446 cell lines were irradiated with LDR at different doses (20-100 mGy). In response to 20 to 75 mGy X-rays, cell proliferation was significantly increased in 2BS but not in NCI-H446 cells. In 2BS cells, LDR at 20 to 75 mGy also stimulated phosphorylation of MAPK/ERK pathway proteins including ERK, MEK, and Raf and of the PI3K/AKT pathway protein AKT. To test whether ERK1/2 and AKT pathway activation was involved in the stimulation of cell proliferation in 2BS cells, the MAPK/ERK and PI3K/AKT pathways were inhibited using their specific inhibitors, U0126 and LY294002. U0126 decreased the phosphorylation of ERK1/2, and LY294002 decreased the phosphorylation of AKT; each could significantly inhibit LDR-induced 2BS cell proliferation. However, LDR did not stimulate these kinases, and kinase inhibitors also did not affect cell proliferation in the NCI-H446 cells. These results suggest that LDR stimulates cell proliferation via the activation of both MAPK/ERK and PI3K/AKT signaling pathways in 2BS but not in NCI-H446 cells. This finding implies the potential for applying LDR to protect normal tissues from radiotherapy without diminishing the efficacy of tumor therapy. PMID:26788032

Effects of low dose pre-irradiation on hepatic damage and genetic material damage caused by cyclophosphamide.

PubMed

Yu, H-S; Song, A-Q; Liu, N; Wang, H

2014-01-01

Cyclophosphamide (CTX) can attack tumour cells, but can also damage the other cells and microstructures of an organism at different levels, such as haematopoietic cells, liver cells, peripheral lymphocyte DNA, and genetic materials. Low dose radiation (LDR) can induce general adaptation reaction. In this study, we explore the effects of low dose radiation on hepatic damage and genetic material damage caused by CTX. Mice were implanted subcutaneously with S180 cells in the left groin (control group excluded). On days 8 and 11, mice of the LDR and LDR+CTX groups were given 75 mGy of whole-body γ-irradiation; whereas mice of the CTX and LDR+CTX groups were injected intraperitoneally with 3.0 mg of CTX. All mice were sacrificed on day 13. DNA damage of the peripheral lymphocytes, alanine aminotransferase (ALT) activity, total protein (TP), albumin (ALB) of the plasma, malonyl-dialdheyde (MDA) content, superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) activity of the hepatic homogenate, and micronucleus frequency (MNF) of polychromatoerythrocytes in the bone marrow were analysed. The control group had the lowest MDA content and the highest SOD and GSH-PX activity, whereas the CTX group had the highest MDA content and the lowest SOD and GSH-PX activity. Compared with the CTX group, the MDA content decreased significantly (p < 0.01) and the SOD and GSH-PX activity increased significantly (p < 0.05) in the LDR+CTX group. TP and ALB in control group were higher than that of the other groups. Compared with the sham-irradiated group, TP and ALB in the LDR group elevated significantly (p < 0.05). The control group had the lightest DNA damage, whereas the CTX group had the severest. DNA damage in LDR+CTX group was much lighter compared with that of the CTX group (p < 0.05). MNF in the CTX group increased significantly compared with the control and the sham-irradiated groups (p < 0.01). Compared with the CTX group, MNF in LDR+CTX group had a tendency of decline, but without statistical significance (p > 0.05). Pre-chemotherapeutic LDR can induce the activities of anti-oxidative enzymes and promote the elimination of free radicles to alleviate the damaging effects of oxidative stress to hepatic tissue caused by high-dose CTX. At the same time, LDR has no obvious effect on the ALT activity of plasma, but may have protective effect on the protein synthesis function of the liver. High-dose CTX chemotherapy can cause DNA damage of peripheral lymphocytes; however, LDR before chemotherapy may have certain protective effect on DNA damage. Moreover, CTX has potent mutagenic effect; however, LDR may have no protective effect against the genetic toxicity of CTX chemotherapy.

Dropout Rates in Texas School Districts: Influences of School Size and Ethnic Group.

ERIC Educational Resources Information Center

Toenjes, Laurence A.

Longitudinal dropout rates (LDR's) for public school students and LDR's of pupil membership by ethnic group based on two Texas Education Agency reports are estimated. LDR's are calculated for the state, by school district size, for the 21 largest districts, and by average high school size. Findings dispel the prevalent perception of the dropout…

Visual Analytics for Exploration of a High-Dimensional Structure

DTIC Science & Technology

2013-04-01

5 Figure 3. Comparison of Euclidean vs. geodesic distance. LDRs use...manifold, whereas an LDR fails. ...........................6 Figure 4. WEKA GUI for data mining HDD using FRFS-ACO...multidimensional scaling (CMDS)— are a linear DR ( LDR ). An LDR is based on a linear combination of the feature data. LDRs keep similar data points close together

Chronic low-dose γ-irradiation of Drosophila melanogaster larvae induces gene expression changes and enhances locomotive behavior

PubMed Central

Kim, Cha Soon; Seong, Ki Moon; Lee, Byung Sub; Lee, In Kyung; Yang, Kwang Hee; Kim, Ji-Young; Nam, Seon Young

2015-01-01

Although radiation effects have been extensively studied, the biological effects of low-dose radiation (LDR) are controversial. This study investigates LDR-induced alterations in locomotive behavior and gene expression profiles of Drosophila melanogaster. We measured locomotive behavior using larval pupation height and the rapid iterative negative geotaxis (RING) assay after exposure to 0.1 Gy γ-radiation (dose rate of 16.7 mGy/h). We also observed chronic LDR effects on development (pupation and eclosion rates) and longevity (life span). To identify chronic LDR effects on gene expression, we performed whole-genome expression analysis using gene-expression microarrays, and confirmed the results using quantitative real-time PCR. The pupation height of the LDR-treated group at the first larval instar was significantly higher (∼2-fold increase in PHI value, P < 0.05). The locomotive behavior of LDR-treated male flies (∼3 − 5 weeks of age) was significantly increased by 7.7%, 29% and 138%, respectively (P < 0.01), but pupation and eclosion rates and life spans were not significantly altered. Genome-wide expression analysis identified 344 genes that were differentially expressed in irradiated larvae compared with in control larvae. We identified several genes belonging to larval behavior functional groups such as locomotion (1.1%), oxidation reduction (8.0%), and genes involved in conventional functional groups modulated by irradiation such as defense response (4.9%), and sensory and perception (2.5%). Four candidate genes were confirmed as differentially expressed genes in irradiated larvae using qRT-PCR (>2-fold change). These data suggest that LDR stimulates locomotion-related genes, and these genes can be used as potential markers for LDR. PMID:25792464

Non-Destructive Evaluation of Kissing Bonds using Local Defect Resonance (LDR) Spectroscopy: A Simulation Study

NASA Astrophysics Data System (ADS)

Delrue, S.; Tabatabaeipour, M.; Hettler, J.; Van Den Abeele, K.

With the growing demand from industry to optimize and further develop existing Non-Destructive Testing & Evaluation (NDT&E) techniques or new methods to detect and characterize incipient damage with high sensitivity and increased quality, ample efforts have been devoted to better understand the typical behavior of kissing bonds, such as delaminations and cracks. Recently, it has been shown experimentally that the nonlinear ultrasonic response of kissing bonds could be enhanced by using Local Defect Resonance (LDR) spectroscopy. LDR spectroscopy is an efficient NDT technique that takes advantage of the characteristic fre- quencies of the defect (defect resonances) in order to provide maximum acoustic wave-defect interaction. In fact, for nonlinear methodologies, the ultrasonic excitation of the sample should occur at either multiples or integer ratios of the characteristic defect resonance frequencies, in order to obtain the highest signal-to-noise response in the nonlinear LDR spectroscopy. In this paper, the potential of using LDR spectroscopy for the detection, localization and characterization of kissing bonds is illustrated using a 3D simulation code for elastic wave propagation in materials containing closed but dynamically active cracks or delaminations. Using the model, we are able to define an appropriate method, based on the Scaling Subtraction Method (SSM), to determine the local defect resonance frequencies of a delamination in a composite plate and to illustrate an increase in defect nonlinearity due to LDR. The simulation results will help us to obtain a better understanding of the concept of LDR and to assist in the further design and testing of LDR spectroscopy for the detection, localization and characterization of kissing bonds.

Effect of central obscuration on the LDR point spread function

NASA Technical Reports Server (NTRS)

Vanzyl, Jakob J.

1988-01-01

It is well known that Gaussian apodization of an aperture reduces the sidelobe levels of its point spread function (PSF). In the limit where the standard deviation of the Gaussian function is much smaller than the diameter of the aperture, the sidelobes completely disappear. However, when Gaussian apodization is applied to the Large Deployable Reflector (LDR) array consisting of 84 hexagonal panels, it is found that the sidelobe level only decreases by about 2.5 dB. The reason for this is explained. The PSF is shown for an array consisting of 91 uniformly illuminated hexagonal apertures; this array is identical to the LDR array, except that the central hole in the LDR array is filled with seven additional panels. For comparison, the PSF of the uniformly illuminated LDR array is shown. Notice that it is already evident that the sidelobe structure of the LDR array is different from that of the full array of 91 panels. The PSF's of the same two arrays are shown, but with the illumination apodized with a Gaussian function to have 20 dB tapering at the edges of the arrays. While the sidelobes of the full array have decreased dramatically, those of the LDR array changed in structure, but stayed at almost the same level. This result is not completely surprising, since the Gaussian apodization tends to emphasize the contributions from the central portion of the array; exactly where the hole in the LDR array is located. The two most important conclusions are: the size of the central hole should be minimized, and a simple Gaussian apodization scheme to suppress the sidelobes in the PSF should not be used. A more suitable apodization scheme would be a Gaussian annular ring.

Minimal percentage of dose received by 90% of the urethra (%UD90) is the most significant predictor of PSA bounce in patients who underwent low-dose-rate brachytherapy (LDR-brachytherapy) for prostate cancer.

PubMed

Tanaka, Nobumichi; Asakawa, Isao; Fujimoto, Kiyohide; Anai, Satoshi; Hirayama, Akihide; Hasegawa, Masatoshi; Konishi, Noboru; Hirao, Yoshihiko

2012-09-14

To clarify the significant clinicopathological and postdosimetric parameters to predict PSA bounce in patients who underwent low-dose-rate brachytherapy (LDR-brachytherapy) for prostate cancer. We studied 200 consecutive patients who received LDR-brachytherapy between July 2004 and November 2008. Of them, 137 patients did not receive neoadjuvant or adjuvant androgen deprivation therapy. One hundred and forty-two patients were treated with LDR-brachytherapy alone, and 58 were treated with LDR-brachytherapy in combination with external beam radiation therapy. The cut-off value of PSA bounce was 0.1 ng/mL. The incidence, time, height, and duration of PSA bounce were investigated. Clinicopathological and postdosimetric parameters were evaluated to elucidate independent factors to predict PSA bounce in hormone-naïve patients who underwent LDR-brachytherapy alone. Fifty patients (25%) showed PSA bounce and 10 patients (5%) showed PSA failure. The median time, height, and duration of PSA bounce were 17 months, 0.29 ng/mL, and 7.0 months, respectively. In 103 hormone-naïve patients treated with LDR-brachytherapy alone, and univariate Cox proportional regression hazard model indicated that age and minimal percentage of the dose received by 30% and 90% of the urethra were independent predictors of PSA bounce. With a multivariate Cox proportional regression hazard model, minimal percentage of the dose received by 90% of the urethra was the most significant parameter of PSA bounce. Minimal percentage of the dose received by 90% of the urethra was the most significant predictor of PSA bounce in hormone-naïve patients treated with LDR-brachytherapy alone.

Basic and applied research related to the technology of space energy conversion systems

NASA Technical Reports Server (NTRS)

Hertzberg, A.; Mattick, A. T.; Bruckner, A. P.

1988-01-01

The first six months' research effort on the Liquid Droplet Radiator (LDR) focussed on experimental and theoretical studies of radiation by an LDR droplet cloud. Improvements in the diagnostics for the radiation facility have been made which have permitted an accurate experimental test of theoretical predictions of LDR radiation over a wide range of optical depths, using a cloud of Dow silicone oil droplets. In conjunction with these measurements an analysis was made of the evolution of the cylindrical droplet cloud generated by a 2300-hole orifice plate. This analysis indicates that a considerable degree of agglomeration of droplets occurs over the first meter of travel. Theoretical studies have centered on developments of an efficient means of computing the angular scattering distribution from droplets in an LDR droplet cloud, so that a parameter study can be carried out for LDR radiative performance vs fluid optical properties and cloud geometry.

Feature Extraction of High-Dimensional Structures for Exploratory Analytics

DTIC Science & Technology

2013-04-01

Comparison of Euclidean vs. geodesic distance. LDRs use metric based on the Euclidean distance between two points, while the NLDRs are based on...geodesic distance. An NLDR successfully unrolls the curved manifold, whereas an LDR fails. ...........................3 1 1. Introduction An...and classical metric multidimensional scaling, are a linear DR ( LDR ). An LDR is based on a linear combination of

Advanced Extremely High Frequency Satellite (AEHF)

DTIC Science & Technology

2013-12-01

terminals Milstar Backward Compatible Operate with the Milstar system, at all LDR and MDR terminal supported data rates, throughout the Milstar...transition to the AEHF system Operate with the Milstar system, at all LDR and MDR terminal supported data rates, throughout the Milstar...transition to the AEHF system Operate with the Milstar system, at all LDR and MDR terminal supported data rates, throughout the Milstar

Structural design of the Large Deployable Reflector (LDR)

NASA Technical Reports Server (NTRS)

Satter, Celeste M.; Lou, Michael C.

1991-01-01

An integrated Large Deployable Reflector (LDR) analysis model was developed to enable studies of system responses to the mechanical and thermal disturbances anticipated during on-orbit operations. Functional requirements of the major subsystems of the LDR are investigated, design trades are conducted, and design options are proposed. System mass and inertia properties are computed in order to estimate environmental disturbances, and in the sizing of control system hardware. Scaled system characteristics are derived for use in evaluating launch capabilities and achievable orbits. It is concluded that a completely passive 20-m primary appears feasible for the LDR from the standpoint of both mechanical vibration and thermal distortions.

Intervening to promote early initiation of breastfeeding in the LDR.

PubMed

Komara, Carol; Simpson, Diana; Teasdale, Carla; Whalen, Gaye; Bell, Shay; Giovanetto, Laurie

2007-01-01

To evaluate the effectiveness of an interventional protocol for the early initiation of breastfeeding that would remove barriers in the labor, delivery, recovery (LDR) unit. Descriptive design using 100 postpartum mothers who were interviewed before discharge at a large university hospital in the south-central United States. Descriptive statistics were used for analysis. The protocol was effective for initiating breastfeeding, and breastfeeding increased from 53% to 66%. When barriers to breastfeeding are reduced in the LDR setting, women will breastfeed. It is possible that reducing hospital barriers to breastfeeding in the LDR can also set the stage for sustained breastfeeding during hospitalization and for less supplementation with formula.

Pointing control for LDR

NASA Technical Reports Server (NTRS)

Yam, Y.; Briggs, C.

1988-01-01

One important aspect of the LDR control problem is the possible excitations of structural modes due to random disturbances, mirror chopping, and slewing maneuvers. An analysis was performed to yield a first order estimate of the effects of such dynamic excitations. The analysis involved a study of slewing jitters, chopping jitters, disturbance responses, and pointing errors, making use of a simplified planar LDR model which describes the LDR dynamics on a plane perpendicular to the primary reflector. Briefly, the results indicate that the command slewing profile plays an important role in minimizing the resultant jitter, even to a level acceptable without any control action. An optimal profile should therefore be studied.

Structural design of the Large Deployable Reflector (LDR)

NASA Astrophysics Data System (ADS)

Satter, Celeste M.; Lou, Michael C.

1991-09-01

An integrated Large Deployable Reflector (LDR) analysis model was developed to enable studies of system responses to the mechanical and thermal disturbances anticipated during on-orbit operations. Functional requirements of the major subsystems of the LDR are investigated, design trades are conducted, and design options are proposed. System mass and inertia properties are computed in order to estimate environmental disturbances, and in the sizing of control system hardware. Scaled system characteristics are derived for use in evaluating launch capabilities and achievable orbits. It is concluded that a completely passive 20-m primary appears feasible for the LDR from the standpoint of both mechanical vibration and thermal distortions.

The liquid droplet radiator: Status of development

NASA Astrophysics Data System (ADS)

Persson, J.

1991-12-01

The ever greater amounts of power to be dissipated onboard future spacecraft, together with their limited external dimensions, will make it increasingly difficult to use conventional radiator technology without imposing a severe mass penalty. Hunting for lightweight alternatives to current heat rejection systems has become a matter of growing urgency, which explains the great interest that the Liquid Droplet Radiator (LDR) has attracted. Tradeoff analyses indicate that an LDR may be as much as an order of magnitude lighter than a comparable conventional radiator. A literature study examining the progress of the LDR research and some of its possible applications is reviewed. An investigation of the LDR heat rejection capability is presented.

A Comparison Between Low-Dose-Rate Brachytherapy With or Without Androgen Deprivation, External Beam Radiation Therapy With or Without Androgen Deprivation, and Radical Prostatectomy With or Without Adjuvant or Salvage Radiation Therapy for High-Risk Prostate Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ciezki, Jay P., E-mail: ciezkij@ccf.org; Weller, Michael; Reddy, Chandana A.

Purpose: We compare the efficacy and toxicity among the 3 major modalities available used to treat high-risk prostate cancer (HRCaP). Methods and Materials: From 1996 to 2012, 2557 HRCaP patients were treated: 734 received external beam radiation therapy (EBRT) with or without androgen deprivation therapy (ADT), 515 received low-dose-rate prostate brachytherapy (LDR) with or without ADT, and 1308 received radical prostatectomy (RP) with or without EBRT. Biochemical relapse-free survival (bRFS), clinical relapse-free survival (cRFS), and prostate cancer–specific mortality (PCSM) were assessed. Toxicity was assessed using the Common Terminology Criteria for Adverse Events, version 4.03. The log-rank test compared bRFS andmore » cRFS among the modalities, and Cox regression identified factors associated with bRFS and cRFS. Gray's test compared differences in late toxicity and PSCM among the modalities. Competing risk regression identified factors associated with PCSM. Results: The median follow-up time and age were 63.5 months and 65 years, respectively. The bRFS at 5 and 10 years, respectively, was 74% and 53% for EBRT, 74% and 52% for LDR, and 65% and 47% for RP (P=.0001). The cRFS at 5 and 10 years, respectively, was 85% and 73% for EBRT, 90% and 76% for LDR, and 89% and 75% for RP (P=.121). The PCSM at 5 and 10 years, respectively, was 5.3% and 11.2% for EBRT, 3.2% and 3.6% for LDR, and 2.8% and 6.8% for RP (P=.0004). The 10-year cumulative incidence of ≥grade 3 genitourinary toxicity was 8.1% for EBRT, 7.2% for LDR, and 16.4% for RP (P<.0001). The 10-year cumulative incidence of ≥grade 3 gastrointestinal toxicity was 4.6% for EBRT, 1.1% for LDR, and 1.0% for RP (P<.0001). Conclusion: HRCaP treated with EBRT, LDR, or RP yields efficacy showing better bRFS for LDR and EBRT relative to RP, equivalence for cRFS, and a PCSM advantage of LDR and RP over EBRT. The toxicity is lowest for LDR.« less

A Comparison Between Low-Dose-Rate Brachytherapy With or Without Androgen Deprivation, External Beam Radiation Therapy With or Without Androgen Deprivation, and Radical Prostatectomy With or Without Adjuvant or Salvage Radiation Therapy for High-Risk Prostate Cancer.

PubMed

Ciezki, Jay P; Weller, Michael; Reddy, Chandana A; Kittel, Jeffrey; Singh, Harguneet; Tendulkar, Rahul; Stephans, Kevin L; Ulchaker, James; Angermeier, Kenneth; Stephenson, Andrew; Campbell, Steven; Haber, Georges-Pascal; Klein, Eric A

2017-04-01

We compare the efficacy and toxicity among the 3 major modalities available used to treat high-risk prostate cancer (HRCaP). From 1996 to 2012, 2557 HRCaP patients were treated: 734 received external beam radiation therapy (EBRT) with or without androgen deprivation therapy (ADT), 515 received low-dose-rate prostate brachytherapy (LDR) with or without ADT, and 1308 received radical prostatectomy (RP) with or without EBRT. Biochemical relapse-free survival (bRFS), clinical relapse-free survival (cRFS), and prostate cancer-specific mortality (PCSM) were assessed. Toxicity was assessed using the Common Terminology Criteria for Adverse Events, version 4.03. The log-rank test compared bRFS and cRFS among the modalities, and Cox regression identified factors associated with bRFS and cRFS. Gray's test compared differences in late toxicity and PSCM among the modalities. Competing risk regression identified factors associated with PCSM. The median follow-up time and age were 63.5 months and 65 years, respectively. The bRFS at 5 and 10 years, respectively, was 74% and 53% for EBRT, 74% and 52% for LDR, and 65% and 47% for RP (P=.0001). The cRFS at 5 and 10 years, respectively, was 85% and 73% for EBRT, 90% and 76% for LDR, and 89% and 75% for RP (P=.121). The PCSM at 5 and 10 years, respectively, was 5.3% and 11.2% for EBRT, 3.2% and 3.6% for LDR, and 2.8% and 6.8% for RP (P=.0004). The 10-year cumulative incidence of ≥grade 3 genitourinary toxicity was 8.1% for EBRT, 7.2% for LDR, and 16.4% for RP (P<.0001). The 10-year cumulative incidence of ≥grade 3 gastrointestinal toxicity was 4.6% for EBRT, 1.1% for LDR, and 1.0% for RP (P<.0001). HRCaP treated with EBRT, LDR, or RP yields efficacy showing better bRFS for LDR and EBRT relative to RP, equivalence for cRFS, and a PCSM advantage of LDR and RP over EBRT. The toxicity is lowest for LDR. Copyright © 2016 Elsevier Inc. All rights reserved.

Simulation requirements for the Large Deployable Reflector (LDR)

NASA Technical Reports Server (NTRS)

Soosaar, K.

1984-01-01

Simulation tools for the large deployable reflector (LDR) are discussed. These tools are often the transfer function variety equations. However, transfer functions are inadequate to represent time-varying systems for multiple control systems with overlapping bandwidths characterized by multi-input, multi-output features. Frequency domain approaches are the useful design tools, but a full-up simulation is needed. Because of the need for a dedicated computer for high frequency multi degree of freedom components encountered, non-real time smulation is preferred. Large numerical analysis software programs are useful only to receive inputs and provide output to the next block, and should be kept out of the direct loop of simulation. The following blocks make up the simulation. The thermal model block is a classical heat transfer program. It is a non-steady state program. The quasistatic block deals with problems associated with rigid body control of reflector segments. The steady state block assembles data into equations of motion and dynamics. A differential raytrace is obtained to establish a change in wave aberrations. The observation scene is described. The focal plane module converts the photon intensity impinging on it into electron streams or into permanent film records.

Differential expression of thymic DNA repair genes in low-dose-rate irradiated AKR/J mice

PubMed Central

Bong, Jin Jong; Kang, Yu Mi; Shin, Suk Chul; Choi, Seung Jin

2013-01-01

We previously determined that AKR/J mice housed in a low-dose-rate (LDR) (137Cs, 0.7 mGy/h, 2.1 Gy) γ-irradiation facility developed less spontaneous thymic lymphoma and survived longer than those receiving sham or high-dose-rate (HDR) (137Cs, 0.8 Gy/min, 4.5 Gy) radiation. Interestingly, histopathological analysis showed a mild lymphomagenesis in the thymus of LDR-irradiated mice. Therefore, in this study, we investigated whether LDR irradiation could trigger the expression of thymic genes involved in the DNA repair process of AKR/J mice. The enrichment analysis of Gene Ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways showed immune response, nucleosome organization, and the peroxisome proliferator-activated receptors signaling pathway in LDR-irradiated mice. Our microarray analysis and quantitative polymerase chain reaction data demonstrated that mRNA levels of Lig4 and RRM2 were specifically elevated in AKR/J mice at 130 days after the start of LDR irradiation. Furthermore, transcriptional levels of H2AX and ATM, proteins known to recruit DNA repair factors, were also shown to be upregulated. These data suggest that LDR irradiation could trigger specific induction of DNA repair-associated genes in an attempt to repair damaged DNA during tumor progression, which in turn contributed to the decreased incidence of lymphoma and increased survival. Overall, we identified specific DNA repair genes in LDR-irradiated AKR/J mice. PMID:23820165

Single-pair fluorescence resonance energy transfer analysis of mRNA transcripts for highly sensitive gene expression profiling in near real time.

PubMed

Peng, Zhiyong; Young, Brandon; Baird, Alison E; Soper, Steven A

2013-08-20

Expression analysis of mRNAs transcribed from certain genes can be used as important sources of biomarkers for in vitro diagnostics. While the use of reverse transcription quantitative PCR (RT-qPCR) can provide excellent analytical sensitivity for monitoring transcript numbers, more sensitive approaches for expression analysis that can report results in near real-time are needed for many critical applications. We report a novel assay that can provide exquisite limits-of-quantitation and consists of reverse transcription (RT) followed by a ligase detection reaction (LDR) with single-pair fluorescence resonance energy transfer (spFRET) to provide digital readout through molecular counting. For this assay, no PCR was employed, which enabled short assay turnaround times. To facilitate implementation of the assay, a cyclic olefin copolymer (COC) microchip, which was fabricated using hot embossing, was employed to carry out the LDR in a continuous flow format with online single-molecule detection following the LDR. As demonstrators of the assay's utility, MMP-7 mRNA was expression profiled from several colorectal cancer cell lines. It was found that the RT-LDR/spFRET assay produced highly linear calibration plots even in the low copy number regime. Comparison to RT-qPCR indicated a better linearity over the low copy number range investigated (10-10,000 copies) with an R(2) = 0.9995 for RT-LDR/spFRET and R(2) = 0.98 for RT-qPCR. In addition, differentiating between copy numbers of 10 and 50 could be performed with higher confidence using RT-LDR/spFRET. To demonstrate the short assay turnaround times obtainable using the RT-LDR/spFRET assay, a two thermal cycle LDR was carried out on amphiphysin gene transcripts that can serve as important diagnostic markers for ischemic stroke. The ability to supply diagnostic information on possible stroke events in short turnaround times using RT-LDR/spFRET will enable clinicians to treat patients effectively with appropriate time-sensitive therapeutics.

Single-Pair Fret Analysis of mRNA Transcripts for Highly Sensitive Gene Expression Profiling in Near Real Time

PubMed Central

Peng, Zhiyong; Young, Brandon; Baird, Alison E.; Soper, Steven A.

2013-01-01

Expression analysis of mRNAs transcribed from certain genes can be used as important sources of biomarkers for in vitro diagnostics. While the use of reverse transcription quantitative PCR (RT-qPCR) can provide excellent analytical sensitivity for monitoring transcript numbers, more sensitive approaches for expression analysis that can report results in near real-time are needed for many critical applications. We report a novel assay that can provide exquisite limits-of-quantitation and consists of reverse transcription (RT) followed by a ligase detection reaction (LDR) with single-pair fluorescence resonance energy transfer (spFRET) to provide digital readout through molecular counting. For this assay, no PCR was employed, which enabled short assay turnaround times. To facilitate implementation of the assay, a cyclic olefin copolymer (COC) microchip, which was fabricated using hot embossing, was employed to carry out the LDR in a continuous flow format with on-line single-molecule detection following the LDR. As demonstrators of the assay's utility, MMP-7 mRNA was expression profiled from several colorectal cancer cell lines. It was found that the RT-LDR/spFRET assay produced highly linear calibration plots even in the low copy number regime. Comparison to RT-qPCR indicated a better linearity over the low copy number range investigated (10 − 10,000 copies) with an R2 = 0.9995 for RT-LDR/spFRET and R2 = 0.98 for RT-qPCR. In addition, differentiating between copy numbers of 10 and 50 could be performed with higher confidence using RT-LDR/spFRET. To demonstrate the short assay turnaround times obtainable using the RT-LDR/spFRET assay, a 2 thermal cycle LDR was carried out on amphiphysin gene transcripts that can serve as important diagnostic markers for ischemic stroke. The ability to supply diagnostic information on possible stroke events in short turnaround times using RT-LDR/spFRET will enable clinicians to treat patients effectively with appropriate time-sensitive therapeutics. PMID:23869556

Serial processing of biological reactions using flow-through microfluidic devices: coupled PCR/LDR for the detection of low-abundant DNA point mutations.

PubMed

Hashimoto, Masahiko; Barany, Francis; Xu, Feng; Soper, Steven A

2007-09-01

We have fabricated a flow-through biochip consisting of passive elements for the analysis of single base mutations in genomic DNA using polycarbonate (PC) as the substrate. The biochip was configured to carry out two processing steps on the input sample, a primary polymerase chain reaction (PCR) followed by an allele-specific ligation detection reaction (LDR) for scoring the presence of low abundant point mutations in genomic DNA. The operation of the device was demonstrated by detecting single nucleotide polymorphisms in gene fragments (K-ras) that carry high diagnostic value for colorectal cancers. The effect of carryover from the primary PCR on the subsequent LDR was investigated in terms of LDR yield and fidelity. We found that a post-PCR treatment step prior to the LDR phase of the assay was not essential. As a consequence, a thermal cycling microchip was used for a sequential PCR/LDR in a simple continuous-flow format, in which the following three steps were carried out: (1) exponential amplification of the gene fragments from genomic DNA; (2) mixing of the resultant PCR product(s) with an LDR cocktail via a Y-shaped passive micromixer; and (3) ligation of two primers (discriminating primer that carried the complement base to the mutation locus being interrogated and a common primer) only when the particular mutation was present in the genomic DNA. We successfully demonstrated the ability to detect one mutant DNA in 1000 normal sequences with the integrated microfluidic system. The PCR/LDR assay using the microchip performed the entire assay at a relatively fast processing speed: 18.7 min for 30 rounds of PCR, 4.1 min for 13 rounds of LDR (total processing time = ca. 22.8 min) and could screen multiple mutations simultaneously in a multiplexed format. In addition, the low cost of the biochip due to the fact that it was fabricated from polymers using replication technologies and consisted of passive elements makes the platform amenable to clinical diagnostics, where one-time use devices are required to eliminate false positives resulting from carryover contamination.

Changes of Space Debris Orbits After LDR Operation

NASA Astrophysics Data System (ADS)

Wnuk, E.; Golebiewska, J.; Jacquelard, C.; Haag, H.

2013-09-01

A lot of technical studies are currently developing concepts of active removal of space debris to protect space assets from on orbit collision. For small objects, such concepts include the use of ground-based lasers to remove or reduce the momentum of the objects thereby lowering their orbit in order to facilitate their decay by re-entry into the Earth's atmosphere. The concept of the Laser Debris Removal (LDR) system is the main subject of the CLEANSPACE project. One of the CLEANSPACE objectives is to define a global architecture (including surveillance, identification and tracking) for an innovative ground-based laser solution, which can remove hazardous medium debris around selected space assets. The CLEANSPACE project is realized by a European consortium in the frame of the European Commission Seventh Framework Programme (FP7), Space topic. The use of sequence of laser operations to remove space debris, needs very precise predictions of future space debris orbital positions, on a level even better than 1 meter. Orbit determination, tracking (radar, optical and laser) and orbit prediction have to be performed with accuracy much better than so far. For that, the applied prediction tools have to take into account all perturbation factors that influence object orbit. The expected object's trajectory after the LDR operation is a lowering of its perigee. To prevent the debris with this new trajectory to collide with another object, a precise trajectory prediction after the LDR sequence is therefore the main task allowing also to estimate re-entry parameters. The LDR laser pulses change the debris object velocity v. The future orbit and re-entry parameters of the space debris after the LDR engagement can be calculated if the resulting ?v vector is known with the sufficient accuracy. The value of the ?v may be estimated from the parameters of the LDR station and from the characteristics of the orbital debris. However, usually due to the poor knowledge of the debris object's size, mass, spin and chemical composition the value and the direction of the vector ?v cannot be estimated with the high accuracy. Therefore, a high precise tracking of the debris will be necessary immediately before the engagement of the LDR and also during this engagement. By extending this tracking and ranging for a few seconds after engagement, the necessary data to evaluate the orbital modification can be produced in the same way as it is done for the catalogue generation. In our paper we discuss the object's orbit changes due to LDR operation for different locations of LDR station and different parameters of the laser energy and telescope diameter. We estimate the future orbit and re-entry parameters taking into account the influence of all important perturbation factors on the space debris orbital motion after LDR.

Cryogenics for LDR

NASA Technical Reports Server (NTRS)

Kittel, Peter

1988-01-01

Three cryogenic questions of importance to Large Deployable Reflector (LDR) are discussed: the primary cooling requirement, the secondary cooling requirement, and the instrument changeout requirement.

Liquid droplet radiator performance studies

NASA Astrophysics Data System (ADS)

Mattick, A. T.; Hertzberg, A.

By making use of droplets rather than solid surfaces to radiate waste heat in space, the liquid droplet radiator (LDR) achieves a radiating area/mass much larger than that of conventional radiators which use fins or heat pipes. The lightweight potential of the LDR is shown to be limited primarily by the radiative properties of the droplets. The requirement that the LDR heat transfer fluid have a very low vapor pressure limits the choice of fluids to relatively few—several liquid metals and Dow 705 silicone fluid are the only suitable candidates so far identified. An experimental determination of the emittance of submillimeter droplets of Dow 705 fluid indicates than an LDR using this fluid at temperatures of 275-335 K would be ⋍ 10 times lighter than the lightest solid surface radiators. Although several liquid metals appear to offer excellent performance in LDR applications at temperatures between 200 K and 975 K, experimental determination of liquid metal emissivities is needed for a conclusive assessment.

Liquid droplet radiator performance studies

NASA Technical Reports Server (NTRS)

Mattick, A. T.; Hertzberg, A.

1984-01-01

By making use of droplets rather than solid surfaces to radiate waste heat in space, the liquid-droplet radiator (LDR) achieves a radiating area/mass much larger than that of conventional radiators which use fins or heat pipes. The light-weight potential of the LDR is shown to be limited primarily by the radiative properties of the droplets. The requirement that the LDR heat-transfer fluid have a very low vapor pressure limits the choice of fluids to relatively few several liquid metals and a silicone fluid are the only suitable candidates so far identified. An experimental determination of the emittance of submillimeter droplets of the silicon fluid indicates that an LDR using this fluid at temperatures of 275-335 K would be about 10 times lighter than the lightest solid-surface radiators. Although several liquid metals appear to offer excellent performance in LDR applications at temperatures between 200 and 975 K, experimental determination of liquid-metal emissivities is needed for a conclusive assessment.

Liquid droplet radiator performance studies

NASA Astrophysics Data System (ADS)

Mattick, A. T.; Hertzberg, A.

1984-10-01

By making use of droplets rather than solid surfaces to radiate waste heat in space, the liquid-droplet radiator (LDR) achieves a radiating area/mass much larger than that of conventional radiators which use fins or heat pipes. The light-weight potential of the LDR is shown to be limited primarily by the radiative properties of the droplets. The requirement that the LDR heat-transfer fluid have a very low vapor pressure limits the choice of fluids to relatively few several liquid metals and a silicone fluid are the only suitable candidates so far identified. An experimental determination of the emittance of submillimeter droplets of the silicon fluid indicates that an LDR using this fluid at temperatures of 275-335 K would be about 10 times lighter than the lightest solid-surface radiators. Although several liquid metals appear to offer excellent performance in LDR applications at temperatures between 200 and 975 K, experimental determination of liquid-metal emissivities is needed for a conclusive assessment.

Gamma radiation at a human relevant low dose rate is genotoxic in mice

NASA Astrophysics Data System (ADS)

Graupner, Anne; Eide, Dag M.; Instanes, Christine; Andersen, Jill M.; Brede, Dag A.; Dertinger, Stephen D.; Lind, Ole C.; Brandt-Kjelsen, Anicke; Bjerke, Hans; Salbu, Brit; Oughton, Deborah; Brunborg, Gunnar; Olsen, Ann K.

2016-09-01

Even today, 70 years after Hiroshima and accidents like in Chernobyl and Fukushima, we still have limited knowledge about the health effects of low dose rate (LDR) radiation. Despite their human relevance after occupational and accidental exposure, only few animal studies on the genotoxic effects of chronic LDR radiation have been performed. Selenium (Se) is involved in oxidative stress defence, protecting DNA and other biomolecules from reactive oxygen species (ROS). It is hypothesised that Se deficiency, as it occurs in several parts of the world, may aggravate harmful effects of ROS-inducing stressors such as ionising radiation. We performed a study in the newly established LDR-facility Figaro on the combined effects of Se deprivation and LDR γ exposure in DNA repair knockout mice (Ogg1-/-) and control animals (Ogg1+/-). Genotoxic effects were seen after continuous radiation (1.4 mGy/h) for 45 days. Chromosomal damage (micronucleus), phenotypic mutations (Pig-a gene mutation of RBCCD24-) and DNA lesions (single strand breaks/alkali labile sites) were significantly increased in blood cells of irradiated animals, covering three types of genotoxic activity. This study demonstrates that chronic LDR γ radiation is genotoxic in an exposure scenario realistic for humans, supporting the hypothesis that even LDR γ radiation may induce cancer.

Local defect resonance (LDR): A route to highly efficient thermosonic and nonlinear ultrasonic NDT

NASA Astrophysics Data System (ADS)

Solodov, Igor

2014-02-01

The concept of LDR is based on the fact that inclusion of a defect leads to a local drop of rigidity for a certain mass of the material that should manifest in a particular characteristic frequency of the defect. A frequency match between the driving ultrasonic wave and this characteristic frequency provides an efficient energy pumping from the wave directly into the defect. For simulated and realistic defects in various materials the LDR-induced local resonance increase in the vibration amplitude averages up to ˜ (20-40 dB). Due to a strong resonance amplification of the local vibrations, the LDR-driven defects manifest a profound nonlinearity even at moderate ultrasonic excitation level. The nonlinearity combined with resonance results in efficient generation of the higher harmonics and is also used as a filter/amplifier in the frequency mixing mode of nonlinear NDT. The LDR high-Q thermal response enables to realize a frequency-selective imaging with an opportunity to distinguish between different defects by changing the driving frequency. The LDR-thermosonics requires much lower acoustic power to activate defects that makes it possible to avoid high-power ultrasonic instrumentation and proceed to a noncontact ultrasonic thermography by using air-coupled ultrasonic excitation.

Optimal conditions of LDR to protect the kidney from diabetes

PubMed Central

Cheng, Jie; Li, Fengsheng; Cui, Jiuwei; Guo, Weiying; Li, Cai; Li, Wei; Wang, Guixia; Xing, Xiao; Gao, Ying; Ge, Yuanyuan; Wang, Guanjun; Cai, Lu

2014-01-01

Aims We reported the attenuation of diabetes-induced renal dysfunction by exposure to multiple low-dose radiation (LDR) at 25 mGy every other day via suppressing renal oxidative damage. We here explored the optimal conditions of LDR to protect the kidney from diabetes. Main methods Type 1 diabetic mice were induced with multiple injections of low-dose streptozotocin in male C57BL/6J mice. Diabetic mice received whole body X-irradiation at dose of 12.5, 25 or 50 mGy every other day for either 4 or 8 weeks. Age-matched normal mice were similarly irradiated at the dose of 25 mGy for 4 or 8 weeks. The renal function and histopathological changes were examined at the 4th and 8th week of the study. Key findings Diabetes induced renal dysfunction, shown by the decreased creatinine and increased microalbumin in urinary. Renal oxidative damage, detected by protein nitration and lipid oxidation, and remodeling, reflected by increased expression of connective tissue growth factor, collagen IV and fibronectin, were significantly increased in diabetic mice. All these renal pathological and function changes in diabetic mice were significantly attenuated by exposure to LDR at all regimens, among which, however, exposure to LDR at 12.5 mGy for 8 weeks provided the best preventive effect on the kidney of diabetic mice. Significance Our results suggest that whole-body LDR at 12.5 mGy every other day for 8 weeks is the optimal condition of LDR to protect the kidney from diabetes. PMID:24631139

Comparison of PSA value at last follow-up of patients who underwent low-dose rate brachytherapy and intensity-modulated radiation therapy for prostate cancer.

PubMed

Tanaka, Nobumichi; Asakawa, Isao; Nakai, Yasushi; Miyake, Makito; Anai, Satoshi; Fujii, Tomomi; Hasegawa, Masatoshi; Konishi, Noboru; Fujimoto, Kiyohide

2017-08-25

To compare the PSA value at the last follow-up of patients who underwent prostate low-dose rate brachytherapy (LDR-BT) with that of patients who underwent intensity-modulated radiation therapy (IMRT). A total of 610 prostate cancer patients (cT1c-3bN0M0) were enrolled, and 445 of them underwent LDR-BT, while 165 received IMRT (74-76 Gy). The median follow-up period of these two groups was 75 months (LDR-BT) and 78 months (IMRT), respectively. We also evaluated the biochemical recurrence (BCR)-free rate using two definitions (Phoenix definition and PSA ≥ 0.2 ng/mL). The percentage of patients who achieved PSA < 0.2 ng/mL at the last follow-up was 77.5% in the LDR-BT group and 49.7% in the IMRT group (p < 0.001). Among patients with a normal testosterone level at the last follow-up, the percentage of those who achieved PSA < 0.2 ng/mL at the last follow-up was 79.2% in the LDR-BT group and 32.1% in the IMRT group (p < 0.001). The 5-year BCR-free rate by the Phoenix definition in the IMRT and LDR-BT groups was 89.5 and 95.0% (p < 0.001), respectively. On the other hand, the 5-year BCR-free rate using the definition of PSA ≥ 0.2 ng/mL was 59.1 and 80.1% in the IMRT and LDR-BT groups, respectively (p < 0.001). The PSA value at the last follow-up of LDR-BT was significantly lower than that of IMRT, and this result was particularly marked in patients with a normal testosterone level at the last follow-up.

Modelling second malignancy risks from low dose rate and high dose rate brachytherapy as monotherapy for localised prostate cancer.

PubMed

Murray, Louise; Mason, Joshua; Henry, Ann M; Hoskin, Peter; Siebert, Frank-Andre; Venselaar, Jack; Bownes, Peter

2016-08-01

To estimate the risks of radiation-induced rectal and bladder cancers following low dose rate (LDR) and high dose rate (HDR) brachytherapy as monotherapy for localised prostate cancer and compare to external beam radiotherapy techniques. LDR and HDR brachytherapy monotherapy plans were generated for three prostate CT datasets. Second cancer risks were assessed using Schneider's concept of organ equivalent dose. LDR risks were assessed according to a mechanistic model and a bell-shaped model. HDR risks were assessed according to a bell-shaped model. Relative risks and excess absolute risks were estimated and compared to external beam techniques. Excess absolute risks of second rectal or bladder cancer were low for both LDR (irrespective of the model used for calculation) and HDR techniques. Average excess absolute risks of rectal cancer for LDR brachytherapy according to the mechanistic model were 0.71 per 10,000 person-years (PY) and 0.84 per 10,000 PY respectively, and according to the bell-shaped model, were 0.47 and 0.78 per 10,000 PY respectively. For HDR, the average excess absolute risks for second rectal and bladder cancers were 0.74 and 1.62 per 10,000 PY respectively. The absolute differences between techniques were very low and clinically irrelevant. Compared to external beam prostate radiotherapy techniques, LDR and HDR brachytherapy resulted in the lowest risks of second rectal and bladder cancer. This study shows both LDR and HDR brachytherapy monotherapy result in low estimated risks of radiation-induced rectal and bladder cancer. LDR resulted in lower bladder cancer risks than HDR, and lower or similar risks of rectal cancer. In absolute terms these differences between techniques were very small. Compared to external beam techniques, second rectal and bladder cancer risks were lowest for brachytherapy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Multiple Low-Dose Radiation Prevents Type 2 Diabetes-Induced Renal Damage through Attenuation of Dyslipidemia and Insulin Resistance and Subsequent Renal Inflammation and Oxidative Stress

PubMed Central

Shao, Minglong; Lu, Xuemian; Cong, Weitao; Xing, Xiao; Tan, Yi; Li, Yunqian; Li, Xiaokun; Jin, Litai; Wang, Xiaojie; Dong, Juancong; Jin, Shunzi; Zhang, Chi; Cai, Lu

2014-01-01

Background Dyslipidemia and lipotoxicity-induced insulin resistance, inflammation and oxidative stress are the key pathogeneses of renal damage in type 2 diabetes. Increasing evidence shows that whole-body low dose radiation (LDR) plays a critical role in attenuating insulin resistance, inflammation and oxidative stress. Objective The aims of the present study were to investigate whether LDR can prevent type 2 diabetes-induced renal damage and the underlying mechanisms. Methods Mice were fed with a high-fat diet (HFD, 40% of calories from fat) for 12 weeks to induce obesity followed by a single intraperitoneal injection of streptozotocin (STZ, 50 mg/kg) to develop a type 2 diabetic mouse model. The mice were exposed to LDR at different doses (25, 50 and 75 mGy) for 4 or 8 weeks along with HFD treatment. At each time-point, the kidney weight, renal function, blood glucose level and insulin resistance were examined. The pathological changes, renal lipid profiles, inflammation, oxidative stress and fibrosis were also measured. Results HFD/STZ-induced type 2 diabetic mice exhibited severe pathological changes in the kidney and renal dysfunction. Exposure of the mice to LDR for 4 weeks, especially at 50 and 75 mGy, significantly improved lipid profiles, insulin sensitivity and protein kinase B activation, meanwhile, attenuated inflammation and oxidative stress in the diabetic kidney. The LDR-induced anti-oxidative effect was associated with up-regulation of renal nuclear factor E2-related factor-2 (Nrf-2) expression and function. However, the above beneficial effects were weakened once LDR treatment was extended to 8 weeks. Conclusion These results suggest that LDR exposure significantly prevented type 2 diabetes-induced kidney injury characterized by renal dysfunction and pathological changes. The protective mechanisms of LDR are complicated but may be mainly attributed to the attenuation of dyslipidemia and the subsequent lipotoxicity-induced insulin resistance, inflammation and oxidative stress. PMID:24651118

Time-driven activity-based costing of low-dose-rate and high-dose-rate brachytherapy for low-risk prostate cancer.

PubMed

Ilg, Annette M; Laviana, Aaron A; Kamrava, Mitchell; Veruttipong, Darlene; Steinberg, Michael; Park, Sang-June; Burke, Michael A; Niedzwiecki, Douglas; Kupelian, Patrick A; Saigal, Christopher

Cost estimates through traditional hospital accounting systems are often arbitrary and ambiguous. We used time-driven activity-based costing (TDABC) to determine the true cost of low-dose-rate (LDR) and high-dose-rate (HDR) brachytherapy for prostate cancer and demonstrate opportunities for cost containment at an academic referral center. We implemented TDABC for patients treated with I-125, preplanned LDR and computed tomography based HDR brachytherapy with two implants from initial consultation through 12-month followup. We constructed detailed process maps for provision of both HDR and LDR. Personnel, space, equipment, and material costs of each step were identified and used to derive capacity cost rates, defined as price per minute. Each capacity cost rate was then multiplied by the relevant process time and products were summed to determine total cost of care. The calculated cost to deliver HDR was greater than LDR by $2,668.86 ($9,538 vs. $6,869). The first and second HDR treatment day cost $3,999.67 and $3,955.67, whereas LDR was delivered on one treatment day and cost $3,887.55. The greatest overall cost driver for both LDR and HDR was personnel at 65.6% ($4,506.82) and 67.0% ($6,387.27) of the total cost. After personnel costs, disposable materials contributed the second most for LDR ($1,920.66, 28.0%) and for HDR ($2,295.94, 24.0%). With TDABC, the true costs to deliver LDR and HDR from the health system perspective were derived. Analysis by physicians and hospital administrators regarding the cost of care afforded redesign opportunities including delivering HDR as one implant. Our work underscores the need to assess clinical outcomes to understand the true difference in value between these modalities. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

Conceptual design of liquid droplet radiator shuttle-attached experiment

NASA Technical Reports Server (NTRS)

Pfeiffer, Shlomo L.

1989-01-01

The conceptual design of a shuttle-attached liquid droplet radiator (LDR) experiment is discussed. The LDR is an advanced, lightweight heat rejection concept that can be used to reject heat from future high-powered space platforms. In the LDR concept, submillimeter-sized droplets are generated, pass through space, radiate heat before they are collected, and recirculated back to the heat source. The LDR experiment is designed to be attached to the shuttle longeron and integrated into the shuttle bay using standard shuttle/experiment interfaces. Overall power, weight, and data requirements of the experiment are detailed. The conceptual designs of the droplet radiator, droplet collector, and the optical diagnostic system are discussed in detail. Shuttle integration and safety design issues are also discussed.

Hormetic Response to Low-Dose Radiation: Focus on the Immune System and Its Clinical Implications

PubMed Central

Cui, Jiuwei; Yang, Guozi; Pan, Zhenyu; Zhao, Yuguang; Liang, Xinyue; Li, Wei; Cai, Lu

2017-01-01

The interrelationship between ionizing radiation and the immune system is complex, multifactorial, and dependent on radiation dose/quality and immune cell type. High-dose radiation usually results in immune suppression. On the contrary, low-dose radiation (LDR) modulates a variety of immune responses that have exhibited the properties of immune hormesis. Although the underlying molecular mechanism is not fully understood yet, LDR has been used clinically for the treatment of autoimmune diseases and malignant tumors. These advancements in preclinical and clinical studies suggest that LDR-mediated immune modulation is a well-orchestrated phenomenon with clinical potential. We summarize recent developments in the understanding of LDR-mediated immune modulation, with an emphasis on its potential clinical applications. PMID:28134809

Brachytherapy improves biochemical failure-free survival in low- and intermediate-risk prostate cancer compared with conventionally fractionated external beam radiation therapy: a propensity score matched analysis.

PubMed

Smith, Graham D; Pickles, Tom; Crook, Juanita; Martin, Andre-Guy; Vigneault, Eric; Cury, Fabio L; Morris, Jim; Catton, Charles; Lukka, Himu; Warner, Andrew; Yang, Ying; Rodrigues, George

2015-03-01

To compare, in a retrospective study, biochemical failure-free survival (bFFS) and overall survival (OS) in low-risk and intermediate-risk prostate cancer patients who received brachytherapy (BT) (either low-dose-rate brachytherapy [LDR-BT] or high-dose-rate brachytherapy with external beam radiation therapy [HDR-BT+EBRT]) versus external beam radiation therapy (EBRT) alone. Patient data were obtained from the ProCaRS database, which contains 7974 prostate cancer patients treated with primary radiation therapy at four Canadian cancer institutions from 1994 to 2010. Propensity score matching was used to obtain the following 3 matched cohorts with balanced baseline prognostic factors: (1) low-risk LDR-BT versus EBRT; (2) intermediate-risk LDR-BT versus EBRT; and (3) intermediate-risk HDR-BT+EBRT versus EBRT. Kaplan-Meier survival analysis was performed to compare differences in bFFS (primary endpoint) and OS in the 3 matched groups. Propensity score matching created acceptable balance in the baseline prognostic factors in all matches. Final matches included 2 1:1 matches in the intermediate-risk cohorts, LDR-BT versus EBRT (total n=254) and HDR-BT+EBRT versus EBRT (total n=388), and one 4:1 match in the low-risk cohort (LDR-BT:EBRT, total n=400). Median follow-up ranged from 2.7 to 7.3 years for the 3 matched cohorts. Kaplan-Meier survival analysis showed that all BT treatment options were associated with statistically significant improvements in bFFS when compared with EBRT in all cohorts (intermediate-risk EBRT vs LDR-BT hazard ratio [HR] 4.58, P=.001; intermediate-risk EBRT vs HDR-BT+EBRT HR 2.08, P=.007; low-risk EBRT vs LDR-BT HR 2.90, P=.004). No significant difference in OS was found in all comparisons (intermediate-risk EBRT vs LDR-BT HR 1.27, P=.687; intermediate-risk EBRT vs HDR-BT+EBRT HR 1.55, P=.470; low-risk LDR-BT vs EBRT HR 1.41, P=.500). Propensity score matched analysis showed that BT options led to statistically significant improvements in bFFS in low- and intermediate-risk prostate cancer patient populations. Copyright © 2015 Elsevier Inc. All rights reserved.

Brachytherapy Improves Biochemical Failure–Free Survival in Low- and Intermediate-Risk Prostate Cancer Compared With Conventionally Fractionated External Beam Radiation Therapy: A Propensity Score Matched Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, Graham D.; Pickles, Tom; Crook, Juanita

2015-03-01

Purpose: To compare, in a retrospective study, biochemical failure-free survival (bFFS) and overall survival (OS) in low-risk and intermediate-risk prostate cancer patients who received brachytherapy (BT) (either low-dose-rate brachytherapy [LDR-BT] or high-dose-rate brachytherapy with external beam radiation therapy [HDR-BT+EBRT]) versus external beam radiation therapy (EBRT) alone. Methods and Materials: Patient data were obtained from the ProCaRS database, which contains 7974 prostate cancer patients treated with primary radiation therapy at four Canadian cancer institutions from 1994 to 2010. Propensity score matching was used to obtain the following 3 matched cohorts with balanced baseline prognostic factors: (1) low-risk LDR-BT versus EBRT; (2)more » intermediate-risk LDR-BT versus EBRT; and (3) intermediate-risk HDR-BT+EBRT versus EBRT. Kaplan-Meier survival analysis was performed to compare differences in bFFS (primary endpoint) and OS in the 3 matched groups. Results: Propensity score matching created acceptable balance in the baseline prognostic factors in all matches. Final matches included 2 1:1 matches in the intermediate-risk cohorts, LDR-BT versus EBRT (total n=254) and HDR-BT+EBRT versus EBRT (total n=388), and one 4:1 match in the low-risk cohort (LDR-BT:EBRT, total n=400). Median follow-up ranged from 2.7 to 7.3 years for the 3 matched cohorts. Kaplan-Meier survival analysis showed that all BT treatment options were associated with statistically significant improvements in bFFS when compared with EBRT in all cohorts (intermediate-risk EBRT vs LDR-BT hazard ratio [HR] 4.58, P=.001; intermediate-risk EBRT vs HDR-BT+EBRT HR 2.08, P=.007; low-risk EBRT vs LDR-BT HR 2.90, P=.004). No significant difference in OS was found in all comparisons (intermediate-risk EBRT vs LDR-BT HR 1.27, P=.687; intermediate-risk EBRT vs HDR-BT+EBRT HR 1.55, P=.470; low-risk LDR-BT vs EBRT HR 1.41, P=.500). Conclusions: Propensity score matched analysis showed that BT options led to statistically significant improvements in bFFS in low- and intermediate-risk prostate cancer patient populations.« less

Optimal conditions of LDR to protect the kidney from diabetes: exposure to 12.5 mGy X-rays for 8 weeks efficiently protects the kidney from diabetes.

PubMed

Cheng, Jie; Li, Fengsheng; Cui, Jiuwei; Guo, Weiying; Li, Cai; Li, Wei; Wang, Guixia; Xing, Xiao; Gao, Ying; Ge, Yuanyuan; Wang, Guanjun; Cai, Lu

2014-05-08

We reported the attenuation of diabetes-induced renal dysfunction by exposure to multiple low-dose radiation (LDR) at 25 mGy every other day by suppressing renal oxidative damage. We here explored the optimal conditions of LDR to protect the kidney from diabetes. Male C57BL/6J mice with type 1 diabetes were induced with multiple injections of low-dose streptozotocin. Diabetic mice received whole body X-irradiation at a dose of 12.5, 25 or 50 mGy every other day for either 4 or 8 weeks. Age-matched normal mice were similarly irradiated at the dose of 25 mGy for 4 or 8 weeks. The renal function and histopathological changes were examined at the 4th and 8th weeks of the study. Diabetes induced renal dysfunction is shown by the decreased creatinine and increased microalbumin in the urine. Renal oxidative damage, detected by protein nitration and lipid oxidation, and remodeling, reflected by increased expression of connective tissue growth factor, collagen IV and fibronectin, were significantly increased in diabetic mice. All these renal pathological and function changes in diabetic mice were significantly attenuated by exposure to LDR at all regimens, among which, however, exposure to LDR at 12.5 mGy for 8 weeks provided the best protective effect on the kidney of diabetic mice. Our results suggest that whole-body LDR at 12.5 mGy every other day for 8 weeks is the optimal condition of LDR to protect the kidney from diabetes. Copyright © 2014 Elsevier Inc. All rights reserved.

Transition from LDR to HDR brachytherapy for cervical cancer: Evaluation of tumor control, survival, and toxicity.

PubMed

Romano, K D; Pugh, K J; Trifiletti, D M; Libby, B; Showalter, T N

In 2012, our institution transitioned from low-dose-rate (LDR) brachytherapy to high dose-rate (HDR) brachytherapy. We report clinical outcomes after brachytherapy for cervical cancer at our institution over a continuous 10-year period. From 2004 to 2014, 258 women (184 LDR and 74 HDR) were treated with tandem and ovoid brachytherapy in the multidisciplinary management of International Federation of Gynecology and Obstetrics Stages IA-IVB cervical cancer. Clinical and treatment-related prognostic factors including age, stage, smoking status, relevant doses, and toxicity data were recorded. Median followup for the LDR and HDR groups was 46 months and 12 months, respectively. The majority of patients (92%) received external beam radiotherapy as well as concurrent chemotherapy (83%) before the start of brachytherapy. For all stages, the 1-year local control and overall survival (OS) rates were comparable between the LDR and HDR groups (87% vs. 81%, p = 0.12; and 75% vs. 85%, p = 0.16), respectively. Factors associated with OS on multivariate analysis include age, stage, and nodal involvement. On multivariate analysis, severe toxicity (acute or chronic) was higher with HDR than LDR (24% vs. 10%, p = 0.04). Additional prognostic factors associated with increased severe toxicity include former/current smokers and total dose to lymph nodes. This comparative retrospective analysis of a large cohort of women treated with brachytherapy demonstrates no significant difference in OS or local control between the LDR and HDR. Acute and chronic toxicity increased shortly after the implementation of HDR, highlighting the importance of continued refinement of HDR methods, including integrating advanced imaging. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

Differential cellular responses to prolonged LDR-IR in MLH1-proficient and MLH1-deficient colorectal cancer HCT116 cells.

PubMed

Yan, Tao; Seo, Yuji; Kinsella, Timothy J

2009-11-15

MLH1 is a key DNA mismatch repair (MMR) protein involved in maintaining genomic stability by participating in the repair of endogenous and exogenous mispairs in the daughter strands during S phase. Exogenous mispairs can result following treatment with several classes of chemotherapeutic drugs, as well as with ionizing radiation. In this study, we investigated the role of the MLH1 protein in determining the cellular and molecular responses to prolonged low-dose rate ionizing radiation (LDR-IR), which is similar to the clinical use of cancer brachytherapy. An isogenic pair of MMR(+) (MLH1(+)) and MMR(-) (MLH1(-)) human colorectal cancer HCT116 cells was exposed to prolonged LDR-IR (1.3-17 cGy/h x 24-96 h). The clonogenic survival and gene mutation rates were examined. Cell cycle distribution was analyzed with flow cytometry. Changes in selected DNA damage repair proteins, DNA damage response proteins, and cell death marker proteins were examined with Western blotting. MLH1(+) HCT116 cells showed greater radiosensitivity with enhanced expression of apoptotic and autophagic markers, a reduced HPRT gene mutation rate, and more pronounced cell cycle alterations (increased late-S population and a G(2)/M arrest) following LDR-IR compared with MLH1(-) HCT116 cells. Importantly, a progressive increase in MLH1 protein levels was found in MLH1(+) cells during prolonged LDR-IR, which was temporally correlated with a progressive decrease in Rad51 protein (involved in homologous recombination) levels. MLH1 status significantly affects cellular responses to prolonged LDR-IR. MLH1 may enhance cell radiosensitivity to prolonged LDR-IR through inhibition of homologous recombination (through inhibition of Rad51).

Evaluation of time, attendance of medical staff, and resources during interstitial brachytherapy for prostate cancer : DEGRO-QUIRO trial.

PubMed

Tselis, N; Maurer, U; Popp, W; Sack, H; Zamboglou, N

2014-04-01

The German Society of Radiation Oncology initiated a multicenter trial to evaluate core processes and subprocesses of radiotherapy by prospective evaluation of all important procedures in the most frequent malignancies treated by radiation therapy. The aim of this analysis was to assess the required resources for interstitial high-dose-rate (HDR) and low-dose-rate (LDR) prostate brachytherapy (BRT) based on actual time measurements regarding allocation of personnel and room occupation needed for specific procedures. Two radiotherapy centers (community hospital of Offenbach am Main and community hospital of Eschweiler) participated in this prospective study. Working time of the different occupational groups and room occupancies for the workflow of prostate BRT were recorded and methodically assessed during a 3-month period. For HDR and LDR BRT, a total of 560 and 92 measurements, respectively, were documented. The time needed for treatment preplanning was median 24 min for HDR (n = 112 measurements) and 6 min for LDR BRT (n = 21). Catheter implantation with intraoperative HDR real-time planning (n = 112), postimplantation HDR treatment planning (n = 112), and remotely controlled HDR afterloading irradiation (n = 112) required median 25, 39, and 50 min, respectively. For LDR real-time planning (n = 39) and LDR treatment postplanning (n = 32), the assessed median duration was 91 and 11 min, respectively. Room occupancy and overall mean medical staff times were 194 and 910 min respectively, for HDR, and 113 and 371 min, respectively, for LDR BRT. In this prospective analysis, the resource requirements for the application of HDR and LDR BRT of prostate cancer were assessed methodically and are presented for first time.

β-Cell Failure in Diet-Induced Obese Mice Stratified According to Body Weight Gain: Secretory Dysfunction and Altered Islet Lipid Metabolism Without Steatosis or Reduced β-Cell Mass

PubMed Central

Peyot, Marie-Line; Pepin, Emilie; Lamontagne, Julien; Latour, Martin G.; Zarrouki, Bader; Lussier, Roxane; Pineda, Marco; Jetton, Thomas L.; Madiraju, S.R. Murthy; Joly, Erik; Prentki, Marc

2010-01-01

OBJECTIVE C57Bl/6 mice develop obesity and mild hyperglycemia when fed a high-fat diet (HFD). Although diet-induced obesity (DIO) is a widely studied model of type 2 diabetes, little is known about β-cell failure in these mice. RESEARCH DESIGN AND METHODS DIO mice were separated in two groups according to body weight gain: low- and high-HFD responders (LDR and HDR). We examined whether mild hyperglycemia in HDR mice is due to reduced β-cell mass or function and studied islet metabolism and signaling. RESULTS HDR mice were more obese, hyperinsulinemic, insulin resistant, and hyperglycemic and showed a more altered plasma lipid profile than LDR. LDR mice largely compensated insulin resistance, whereas HDR showed perturbed glucose homeostasis. Neither LDR nor HDR mice showed reduced β-cell mass, altered islet glucose metabolism, and triglyceride deposition. Insulin secretion in response to glucose, KCl, and arginine was impaired in LDR and almost abolished in HDR islets. Palmitate partially restored glucose- and KCl-stimulated secretion. The glucose-induced rise in ATP was reduced in both DIO groups, and the glucose-induced rise in Ca2+ was reduced in HDR islets relatively to LDR. Glucose-stimulated lipolysis was decreased in LDR and HDR islets, whereas fat oxidation was increased in HDR islets only. Fatty acid esterification processes were markedly diminished, and free cholesterol accumulated in HDR islets. CONCLUSIONS β-Cell failure in HDR mice is not due to reduced β-cell mass and glucose metabolism or steatosis but to a secretory dysfunction that is possibly due to altered ATP/Ca2+ and lipid signaling, as well as free cholesterol deposition. PMID:20547980

Comparative analysis between two models of active aging and its influence on body composition, strength levels and quality of life: long-distance runners versus bodybuilders practitioners.

PubMed

Latorre-Román, Pedro Ángel; Izquierdo-Sánchez, Jose Manuel; Salas-Sánchez, Jesús; García-Pinillos, Felipe

2015-04-01

To analyze the body composition, strength level, and the quality of life related to the health (QoL) in veteran sportsmen (>35 years old) in relation to sedentary ones (S), and to compare the result in the mentioned variables between two models of sports practice, long-distance runners (LDR) and bodybuilding practitioners (BBP). One hundred forty-eight male participants took part and were distributed into three groups: 47 LDR (age=42.01±6.96 years), 49 BBP (age=45.14±7.04 years), and 47 S (age=43.71±8.75 years). Body composition, upper- and lower-limb strength level, and QoL were assessed. The LDR and BBP obtained better performance in countermovement jump (CMJ) than the S ones (+0.06 m, p<0.001). Significant differences were found in BMI and %fat mass, between BBP and S with relation to LDR (p<0.001). In relation to the effect of aging on body composition, the muscle mass is reduced in all groups controlled (LDR, BBP, and S). Additionally, the %fat mass is increased only in S group (p< 0.05). The CMJ performance is significantly reduced only in S group (-0.07 m, p<0.001). The results suggested that the LDR as a model of active aging showed healthier values in BMI and %fat mass as well as greater results in QoL than BBP and S groups. Nevertheless, the LDR group showed similar values to S ones in muscle mass. The regression analysis performed showed that the sedentary habit predicts the %fat mass and CMJ performance. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Ligase Detection Reaction for the Analysis of Point Mutations using Free Solution Conjugate Electrophoresis in a Polymer Microfluidic Device

PubMed Central

Sinville, Rondedrick; Coyne, Jennifer; Meagher, Robert J.; Cheng, Yu-Wei; Barany, Francis; Barron, Annelise; Soper, Steven A.

2010-01-01

We have developed a new method for the analysis of low abundant point mutations in genomic DNA using a combination of an allele-specific ligase detection reaction (LDR) with free-solution conjugate electrophoresis (FSCE) to generate and analyze the genetic products. FSCE eliminates the need for a polymer sieving matrix by conjugating chemically synthesized polyamide “drag-tags” onto the LDR primers. The additional drag of the charge-neutral drag-tag breaks the linear scaling of the charge-to-friction ratio of DNA and enables size-based separations of DNA in free solution using electrophoresis with no sieving matrix. We successfully demonstrate the conjugation of polyamide drag-tags onto a set of four LDR primers designed to probe the K-ras oncogene for mutations highly associated with colorectal cancer, the simultaneous generation of fluorescently-labeled LDR/drag-tagged (LDR-dt) products in a multiplexed, single-tube format with mutant:wild-type ratios as low as 1:100, respectively, and the single-base, high-resolution separation of all four LDR-dt products. Separations were conducted in free solution with no polymer network using both a commercial capillary array electrophoresis (CAE) system and a poly(methylmethacrylate), PMMA, microchip replicated via hot-embossing with only a Tris-based running buffer containing additives to suppress the electroosmotic flow (EOF). Typical analysis times for LDR-dt conjugates were 11 min using the CAE system and as low as 85 s for the PMMA microchips. With resolution comparable to traditional gel-based CAE, FSCE along with microchip electrophoresis decreased the separation time by more than a factor of 40. PMID:19053073

Comparative study of LDR (Manchester system) and HDR image-guided conformal brachytherapy of cervical cancer: patterns of failure, late complications, and survival.

PubMed

Narayan, Kailash; van Dyk, Sylvia; Bernshaw, David; Rajasooriyar, Chrishanthi; Kondalsamy-Chennakesavan, Srinivas

2009-08-01

To compare patterns of failure, late toxicities, and survival in locally advanced cervical cancer patients treated by either low-dose-rate (LDR) or conformal high-dose-rate (HDRc) brachytherapy as a part of curative radiotherapy. A retrospective comparative study of 217 advanced cervix cancer patients was conducted; 90 of these patients received LDR and 127 received HDRc brachytherapy. All patients were staged using International Federation of Gynecology and Obstetrics (FIGO) rules, had pretreatment magnetic resonance imaging (MRI), and were treated with concurrent cisplatin chemoradiotherapy. Both groups matched for FIGO stage, MRI tumor volume, and uterine invasion status. Local and pelvic failures were similar 12-13% and 14% both in both groups. Abdominal and systemic failures in LDR group were 21% and 24%, whereas corresponding failures in HDRc group were 20% and 24%. Sixty-eight percent (87/127) of patients treated by HDRc remained asymptomatic, whereas 42% (38/90) of patients were asymptomatic from the bowel and bladder symptoms after treatment with LDR. The 5-year OS rate was 60% (SE = 4%). The 5-year failure-free survival rate was 55% (SE = 3%). There was no significant difference between the groups. Image-guided HDRc planning led to a large decrease in late radiation effects in patients treated by HDRc. Patterns of failure and survival were similar in patients treated either by LDR or HDRc.

Simultaneous detection of 19 K-ras mutations by free-solution conjugate electrophoresis of ligase detection reaction products on glass microchips

PubMed Central

Albrecht, Jennifer Coyne; Kotani, Akira; Lin, Jennifer S.; Soper, Steven A.; Barron, Annelise E.

2015-01-01

We demonstrate here the power and flexibility of free-solution conjugate electrophoresis (FSCE) as a method of separating DNA fragments by electrophoresis with no sieving polymer network. Previous work introduced the coupling of FSCE with ligase detection reaction (LDR) to detect point mutations, even at low abundance compared to the wild-type DNA. Here, four large drag-tags are used to achieve free-solution electrophoretic separation of 19 LDR products ranging in size from 42–66 nt that correspond to mutations in the K-ras oncogene. LDR-FSCE enabled electrophoretic resolution of these 19 LDR-FSCE products by CE in 13.5 minutes (E = 310 V/cm) and by microchip electrophoresis in 140 seconds (E = 350 V/cm). The power of FSCE is demonstrated in the unique characteristic of free-solution separations where the separation resolution is constant no matter the electric field strength. By microchip electrophoresis, the electric field was increased to the maximum of the power supply (E = 700 V/cm), and the 19 LDR-FSCE products were separated in < 70 seconds with almost identical resolution to the separation at E = 350 V/cm. These results will aid the goal of screening K-ras mutations on integrated “sample-in/answer-out” devices with amplification, LDR, and detection all on one platform. PMID:23192597

Repetitive exposure to low-dose X-irradiation attenuates testicular apoptosis in type 2 diabetic rats, likely via Akt-mediated Nrf2 activation

PubMed Central

Zhao, Yuguang; Kong, Chuipeng; Chen, Xiao; Wang, Zhenyu; Wan, Zhiqiang; Jia, Lin; Liu, Qiuju; Wang, Yuehui; Li, Wei; Cui, Jiuwei; Han, Fujun; Cai, Lu

2017-01-01

To determine whether repetitive exposure to low-dose radiation (LDR) attenuates type 2 diabetes (T2DM)-induced testicular apoptotic cell death in a T2DM rat model, we examined the effects of LDR exposure on diabetic and age-matched control rats. We found that testicular apoptosis and oxidative stress levels were significantly higher in T2DM rats than in control rats. In addition, glucose metabolism-related Akt and GSK-3β function was downregulated and Akt negative regulators PTP1B and TRB3 were upregulated in the T2DM group. Superoxide dismutase (SOD) activity and catalase content were also found to be decreased in T2DM rats. These effects were partially prevented or reversed by repetitive LDR exposure. Nrf2 and its downstream genes NQO1, SOD, and catalase were significantly upregulated by repetitive exposure to LDR, suggesting that the reduction of T2DM-induced testicular apoptosis due to repetitive LDR exposure likely involves enhancement of testicular Akt-mediated glucose metabolism and anti-oxidative defense mechanisms. PMID:26704079

A technology program for the development of the large deployable reflector for space based astronomy

NASA Technical Reports Server (NTRS)

Kiya, M. K.; Gilbreath, W. P.; Swanson, P. N.

1982-01-01

Technologies for the development of the Large Deployable Reflector (LDR), a NASA project for the 1990's, for infrared and submillimeter astronomy are presented. The proposed LDR is a 10-30 diameter spaceborne observatory operating in the spectral region from 30 microns to one millimeter, where ground observations are nearly impossible. Scientific rationales for such a system include the study of ancient signals from galaxies at the edge of the universe, the study of star formation, and the observation of fluctuations in the cosmic background radiation. System requirements include the ability to observe faint objects at large distances and to map molecular clouds and H II regions. From these requirements, mass, photon noise, and tolerance budgets are developed. A strawman concept is established, and some alternate concepts are considered, but research is still necessary in the areas of segment, optical control, and instrument technologies.

Robust image registration for multiple exposure high dynamic range image synthesis

NASA Astrophysics Data System (ADS)

Yao, Susu

2011-03-01

Image registration is an important preprocessing technique in high dynamic range (HDR) image synthesis. This paper proposed a robust image registration method for aligning a group of low dynamic range images (LDR) that are captured with different exposure times. Illumination change and photometric distortion between two images would result in inaccurate registration. We propose to transform intensity image data into phase congruency to eliminate the effect of the changes in image brightness and use phase cross correlation in the Fourier transform domain to perform image registration. Considering the presence of non-overlapped regions due to photometric distortion, evolutionary programming is applied to search for the accurate translation parameters so that the accuracy of registration is able to be achieved at a hundredth of a pixel level. The proposed algorithm works well for under and over-exposed image registration. It has been applied to align LDR images for synthesizing high quality HDR images..

Hierarchical tone mapping for high dynamic range image visualization

NASA Astrophysics Data System (ADS)

Qiu, Guoping; Duan, Jiang

2005-07-01

In this paper, we present a computationally efficient, practically easy to use tone mapping techniques for the visualization of high dynamic range (HDR) images in low dynamic range (LDR) reproduction devices. The new method, termed hierarchical nonlinear linear (HNL) tone-mapping operator maps the pixels in two hierarchical steps. The first step allocates appropriate numbers of LDR display levels to different HDR intensity intervals according to the pixel densities of the intervals. The second step linearly maps the HDR intensity intervals to theirs allocated LDR display levels. In the developed HNL scheme, the assignment of LDR display levels to HDR intensity intervals is controlled by a very simple and flexible formula with a single adjustable parameter. We also show that our new operators can be used for the effective enhancement of ordinary images.

Low-dose radiation (LDR) induces hematopoietic hormesis: LDR-induced mobilization of hematopoietic progenitor cells into peripheral blood circulation.

PubMed

Li, Wei; Wang, Guanjun; Cui, Jiuwei; Xue, Lu; Cai, Lu

2004-11-01

The aim of this study was to investigate the stimulating effect of low-dose radiation (LDR) on bone marrow hematopoietic progenitor cell (HPC) proliferation and peripheral blood mobilization. Mice were exposed to 25- to 100-mGy x-rays. Bone marrow and peripheral blood HPCs (BFU-E, CFU-GM, and c-kit+ cells) were measured, and GM-CSF, G-CSF, and IL-3 protein and mRNA expression were detected using ELISA, slot blot hybridization, and Northern blot methods. To functionally evaluate LDR-stimulated and -mobilized HPCs, repopulation of peripheral blood cells in lethally irradiated recipients after transplantation of LDR-treated donor HPCs was examined by WBC counts, animal survival, and colony-forming units in the recipient spleens (CFUs-S). 75-mGy x-rays induced a maximal stimulation for bone marrow HPC proliferation (CFU-GM and BFU-E formation) 48 hours postirradiation, along with a significant increase in HPC mobilization into peripheral blood 48 to 72 hours postradiation, as shown by increases in CFU-GM formation and proportion of c-kit+ cells in the peripheral mononuclear cells. 75-mGy x-rays also maximally induced increases in G-CSF and GM-CSF mRNA expression in splenocytes and levels of serum GM-CSF. To define the critical role of these hematopoietic-stimulating factors in HPC peripheral mobilization, direct administration of G-CSF at a dose of 300 microg/kg/day or 150 microg/kg/day was applied and found to significantly stimulate GM-CFU formation and increase c-kit+ cells in the peripheral mononuclear cells. More importantly, 75-mGy x-rays plus 150 microg/kg/day G-CSF (LDR/150-G-CSF) produced a similar effect to that of 300 microg/kg/day G-CSF alone. Furthermore, the capability of LDR-mobilized donor HPCs to repopulate blood cells was confirmed in lethally irradiated recipient mice by counting peripheral WBC and CFUs-S. These results suggest that LDR induces hematopoietic hormesis, as demonstrated by HPC proliferation and peripheral mobilization, providing a potential approach to clinical application for HPC peripheral mobilization.

Time to PSA rise differentiates the PSA bounce after HDR and LDR brachytherapy of prostate cancer

PubMed Central

Skowronek, Janusz

2018-01-01

Purpose To investigate the differences in prostate-specific antigen (PSA) bounce (PB) after high-dose-rate (HDR-BT) or low-dose-rate (LDR-BT) brachytherapy alone in prostate cancer patients. Materials and methods Ninety-four patients with localized prostate cancer (T1-T2cN0), age ranged 50-81 years, were treated with brachytherapy alone between 2008 and 2010. Patients were diagnosed with adenocarcinoma, Gleason score ≤ 7. The LDR-BT total dose was 144-145 Gy, in HDR-BT – 3 fractions of 10.5 or 15 Gy. The initial PSA level (iPSA) was assessed before treatment, then PSA was rated every 3 months over the first 2 years, and every 6 months during the next 3 years. Median follow-up was 3.0 years. Results Mean iPSA was 7.8 ng/ml. In 58 cases, PSA decreased gradually without PB or biochemical failure (BF). In 24% of patients, PB was observed. In 23 cases (24%), PB was observed using 0.2 ng/ml definition; in 10 cases (11%), BF was diagnosed using nadir + 2 ng/ml definition. The HDR-BT and LDR-BT techniques were not associated with higher level of PB (26 vs. 22%, p = 0.497). Time to the first PSA rise finished with PB was significantly shorter after HDR-BT then after LDR-BT (median, 10.5 vs. 18.0 months) during follow-up. Predictors for PB were observed only after HDR-BT. Androgen deprivation therapy (ADT) and higher Gleason score decreased the risk of PB (HR = 0.11, p = 0.03; HR = 0.51, p = 0.01). The higher PSA nadir and longer time to PSA nadir increased the risk of PB (HR 3.46, p = 0.02; HR 1.04, p = 0.04). There was no predictors for PB after LDR-BT. Conclusions HDR-BT and LDR-BT for low and intermediate risk prostate cancer had similar PB rate. The PB occurred earlier after HDR-BT than after LDR-BT. ADT and higher Gleason score decreased, and higher PSA nadir and longer time to PSA nadir increased the risk of PB after HDR-BT. PMID:29619050

After low and high dose-rate interstitial brachytherapy followed by IMRT radiotherapy for intermediate and high risk prostate cancer.

PubMed

Nakamura, Satoshi; Murakami, Naoya; Inaba, Koji; Wakita, Akihisa; Kobayashi, Kazuma; Takahashi, Kana; Okamoto, Hiroyuki; Umezawa, Rei; Morota, Madoka; Sumi, Minako; Igaki, Hiroshi; Ito, Yoshinori; Itami, Jun

2016-05-03

The study aimed to compare urinary symptoms in patients with clinically localized prostate cancer after a combination of either low-dose-rate or high-dose-rate interstitial brachytherapy along with intensity-modulated radiation therapy (LDR-ISBT + IMRT or HDR-ISBT + IMRT). From June 2009 to April 2014, 16 and 22 patients were treated with LDR-ISBT + IMRT and HDR-ISBT + IMRT, respectively. No patient from these groups was excluded from this study. The prescribed dose of LDR-ISBT, HDR-ISBT, and IMRT was 115 Gy, 20 Gy in 2 fractions, and 46 Gy in 23 fractions, respectively. Obstructive and irritative urinary symptoms were assessed by the International Prostate Symptom Score (IPSS) examined before and after treatments. After ISBT, IPSS was evaluated in the 1st and 4th weeks, then every 2-3 months for the 1st year, and every 6 months thereafter. The median follow-up of the patients treated with LDR-ISBT + IMRT and HDR-ISBT + IMRT was 1070.5 days and 1048.5 days, respectively (p = 0.321). The IPSS-increment in the LDR-ISBT + IMRT group was greater than that in the HDR-ISBT + IMRT between 91 and 180 days after ISBT (p = 0.015). In the LDR-ISBT + IMRT group, the IPSS took longer time to return to the initial level than in the HDR-ISBT + IMRT group (in LDR-ISBT + IMRT group, the recovery time was 90 days later). The dose to urethra showed a statistically significant association with the IPSS-increment in the irritative urinary symptoms (p = 0.011). Clinical outcomes were comparable between both the groups. Both therapeutic modalities are safe and well suited for patients with clinically localized prostate cancer; however, it took patients longer to recover from LDR-ISBT + IMRT than from HDR-ISBT + IMRT. It is possible that fast dose delivery induced early symptoms and early recovery, while gradual dose delivery induced late symptoms and late recovery. Urethral dose reductions were associated with small increments in IPSS.

A Modular Approach To Developing A Large Deployable Reflector

NASA Astrophysics Data System (ADS)

Pittman, R.; Leidich, C.; Mascy, F.; Swenson, B.

1984-01-01

NASA is currently studying the feasibility of developing a Large Deployable Reflector (LDR) astronomical facility to perform astrophysical studies of the infrared and submillimeter portion of the spectrum in the mid 1990's. The LDR concept was recommended by the Astronomy Survey Committee of the National Academy of Sciences as one of two space based projects to be started this decade. The current baseline calls for a 20 m (65.6 ft) aperture telescope diffraction limited at 30 μm and automatically deployed from a single Shuttle launch. The volume, performance, and single launch constraints place great demands on the technology and place LDR beyond the state-of-the-art in certain areas such as lightweight reflector segments. The advent of the Shuttle is opening up many new options and capabilities for producing large space systems. Until now, LDR has always been conceived as an integrated system, deployed autonomously in a single launch. This paper will look at a combination of automatic deployment and on-orbit assembly that may reduce the technological complexity and cost of the LDR system. Many technological tools are now in use or under study that will greatly enhance our capabilities to do assembly in space. Two Shuttle volume budget scenarios will be examined to assess the potential of these tools to reduce the LDR system complexity. Further study will be required to reach the full optimal combination of deployment and assembly, since in most cases the capabilities of these new tools have not been demonstrated. In order to take maximum advantage of these concepts, the design of LDR must be flexible and allow one subsystem to be modified without adversely affecting the entire system. One method of achieving this flexibility is to use a modular design approach in which the major subsystems are physically separated during launch and assembled on orbit. A modular design approach facilitates this flexibility but requires that the subsystems be interfaced in a simple, straightforward, and controlled manner. NASA is currently defining a technology development plan for LDR which will identify the technology advances that are required. The modular approach offers the flexibility to easily incorporate these new advances into the design.

Time to PSA rise differentiates the PSA bounce after HDR and LDR brachytherapy of prostate cancer.

PubMed

Burchardt, Wojciech; Skowronek, Janusz

2018-02-01

To investigate the differences in prostate-specific antigen (PSA) bounce (PB) after high-dose-rate (HDR-BT) or low-dose-rate (LDR-BT) brachytherapy alone in prostate cancer patients. Ninety-four patients with localized prostate cancer (T1-T2cN0), age ranged 50-81 years, were treated with brachytherapy alone between 2008 and 2010. Patients were diagnosed with adenocarcinoma, Gleason score ≤ 7. The LDR-BT total dose was 144-145 Gy, in HDR-BT - 3 fractions of 10.5 or 15 Gy. The initial PSA level (iPSA) was assessed before treatment, then PSA was rated every 3 months over the first 2 years, and every 6 months during the next 3 years. Median follow-up was 3.0 years. Mean iPSA was 7.8 ng/ml. In 58 cases, PSA decreased gradually without PB or biochemical failure (BF). In 24% of patients, PB was observed. In 23 cases (24%), PB was observed using 0.2 ng/ml definition; in 10 cases (11%), BF was diagnosed using nadir + 2 ng/ml definition. The HDR-BT and LDR-BT techniques were not associated with higher level of PB (26 vs. 22%, p = 0.497). Time to the first PSA rise finished with PB was significantly shorter after HDR-BT then after LDR-BT (median, 10.5 vs. 18.0 months) during follow-up. Predictors for PB were observed only after HDR-BT. Androgen deprivation therapy (ADT) and higher Gleason score decreased the risk of PB (HR = 0.11, p = 0.03; HR = 0.51, p = 0.01). The higher PSA nadir and longer time to PSA nadir increased the risk of PB (HR 3.46, p = 0.02; HR 1.04, p = 0.04). There was no predictors for PB after LDR-BT. HDR-BT and LDR-BT for low and intermediate risk prostate cancer had similar PB rate. The PB occurred earlier after HDR-BT than after LDR-BT. ADT and higher Gleason score decreased, and higher PSA nadir and longer time to PSA nadir increased the risk of PB after HDR-BT.

SU-F-T-43: Prediction of Dose Increments by Brain Metastases Resection Cavity Shrinkage Model with I-125 and Cs-131 LDR Seed Implantations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Han, D; Braunstein, S; Sneed, P

Purpose: This work aims to determine dose variability via a brain metastases resection cavity shrinkage model (RC-SM) with I-125 or Cs-131 LDR seed implantations. Methods: The RC-SM was developed to represent sequential volume changes of 95 consecutive brain metastases patients. All patients underwent serial surveillance MR and change in cavity volume was recorded for each patient. For the initial resection cavity, a prolate-ellipsoid cavity model was suggested and applied volume shrinkage rates to correspond to 1.7, 3.6, 5.9, 11.7, and 20.5 months after craniotomy. Extra-ring structure (6mm) was added on a surface of the resection volume and the same shrinkagemore » rates were applied. Total 31 LDR seeds were evenly distributed on the surface of the resection cavity. The Amersham 6711 I-125 seed model (Oncura, Arlington Heights, IL) and the Model Cs-1 Rev2 Cs-131 seed model (IsoRay, Richland, WA) were used for TG-43U1 dose calculation and in-house-programed 3D-volumetric dose calculation system was used for resection cavity rigid model (RC-RM) and the RC-SM dose calculation. Results: The initial resection cavity volume shrunk to 25±6%, 35±6.8%, 42±7.7%, 47±9.5%, and 60±11.6%, with respect to sequential MR images post craniotomy, and the shrinkage rate (SR) was calculated as SR=56.41Xexp(−0.2024Xt)+33.99 and R-square value was 0.98. The normal brain dose as assessed via the dose to the ring structure with the RC-SM showed 29.34% and 27.95% higher than the RC-RM, I-125 and Cs-131, respectively. The dose differences between I-125 and Cs-131 seeds within the same models, I-125 cases were 9.17% and 10.35% higher than Cs-131 cases, the RC-RM and the RC-SM, respectively. Conclusion: A realistic RC-SM should be considered during LDR brain seed implementation and post-implement planning to prevent potential overdose. The RC-SM calculation shows that Cs-131 is more advantageous in sparing normal brain as the resection cavity volume changes with the LDR seeds implementation.« less

Influence of length-to-diameter ratio on shrinkage of basalt fiber concrete

NASA Astrophysics Data System (ADS)

Ruijie, MA; Yang, Jiansen; Liu, Yuan; Zheng, Xiaojun

2017-09-01

In order to study the shrinkage performance of basalt concrete, using the shrinkage rate as index, the work not only studied the influence of different length-to-diameter ratio (LDR) on plastic shrinkage and drying shrinkage of basalt fiber concrete, but also analyzed the action mechanism. The results show that when the fiber content is 0.1%, the LDR of 800 and 1200 take better effects on reducing plastic shrinkage, however the fiber content is 0.3%, that of LDR 600 is better. To improve drying shrinkage, the fiber of LDR 800 takes best effect. In the concrete structure, the adding basalt fibers form a uniform and chaotic supporting system, optimize the pore and the void structure of concrete, make the material further compacted, reduce the water loss, so as to decrease the shrinkage of concrete effectively.

Radiation Dose-Rate Effects on Gene Expression in a Mouse Biodosimetry Model

PubMed Central

Paul, Sunirmal; Smilenov, Lubomir B.; Elliston, Carl D.; Amundson, Sally A.

2015-01-01

In the event of a nuclear accident or radiological terrorist attack, there will be a pressing need for biodosimetry to triage a large, potentially exposed population and to assign individuals to appropriate treatment. Exposures from fallout are likely, resulting in protracted dose delivery that would, in turn, impact the extent of injury. Biodosimetry approaches that can distinguish such low-dose-rate (LDR) exposures from acute exposures have not yet been developed. In this study, we used the C57BL/6 mouse model in an initial investigation of the impact of low-dose-rate delivery on the transcriptomic response in blood. While a large number of the same genes responded to LDR and acute radiation exposures, for many genes the magnitude of response was lower after LDR exposures. Some genes, however, were differentially expressed (P < 0.001, false discovery rate < 5%) in mice exposed to LDR compared with mice exposed to acute radiation. We identified a set of 164 genes that correctly classified 97% of the samples in this experiment as exposed to acute or LDR radiation using a support vector machine algorithm. Gene expression is a promising approach to radiation biodosimetry, enhanced greatly by this first demonstration of its potential for distinguishing between acute and LDR exposures. Further development of this aspect of radiation biodosimetry, either as part of a complete gene expression biodosimetry test or as an adjunct to other methods, could provide vital triage information in a mass radiological casualty event. PMID:26114327

Focal application of low-dose-rate brachytherapy for prostate cancer: a pilot study

PubMed Central

Spadinger, Ingrid T.; Salcudean, Septimiu E.; Kozlowski, Piotr; Chang, Silvia D.; Ng, Tony; Lobo, Julio; Nir, Guy; Moradi, Hamid; Peacock, Michael; Morris, W. James

2017-01-01

Purpose To evaluate the feasibility and to report the early outcomes of focal treatment of prostate cancer using low-dose-rate brachytherapy (LDR-PB). Material and methods Seventeen patients were screened with multi-parametric magnetic resonance imaging (mpMRI), 14 of whom proceeded to receive trans-perineal template mapping biopsy (TTMB). Focal LDR-PB was performed on five eligible patients using dual air kerma strength treatment plans based on planning target volumes derived from cancer locations and determined by TTMB. Patient follow-up includes prostate specific antigen (PSA) measurements, urinary and sexual function questionnaires, repeated imaging and TTMB at specific intervals post-treatment. Results Feasibility of focal LDR-PB was shown and short-term outcomes are promising. While the detection rate of tumors, a majority of which were low grade GS 3 + 3, was found to be low on mpMRI (sensitivity of 37.5%), our results suggest the potential of mpMRI in detecting the presence of higher grade (GS ≥ 3 + 4), and bilateral disease indicating its usefulness as a screening tool for focal LDR-PB. Conclusions Low-dose-rate brachytherapy is a favorable ablation option for focal treatment of prostate cancer, requiring minimal modification to the standard (whole gland) LDR-PB treatment, and appears to have a more favorable side effect profile. Further investigation, in the form of a larger study, is needed to assess the methods used and the long-term outcomes of focal LDR-PB. PMID:28725242

Performance of droplet generator and droplet collector in liquid droplet radiator under microgravity

NASA Astrophysics Data System (ADS)

Totani, T.; Itami, M.; Nagata, H.; Kudo, I.; Iwasaki, A.; Hosokawa, S.

2002-06-01

The Liquid Droplet Radiator (LDR) has an advantage over comparable conventional radiators in terms of the rejected heat power-weight ratio. Therefore, the LDR has attracted attention as an advanced radiator for high-power space systems that will be prerequisite for large space structures. The performance of the LDR under microgravity condition has been studied from the viewpoint of operational space use of the LDR in the future. In this study, the performances of a droplet generator and a droplet collector in the LDR are investigated using drop shafts in Japan: MGLAB and JAMIC. As a result, it is considered that (1) the droplet generator can produce uniform droplet streams in the droplet diameter range from 200 to 280 [µm] and the spacing range from 400 to 950 [µm] under microgravity condition, (2) the droplet collector with the incidence angle of 35 degrees can prevent a uniform droplet stream, in which droplet diameter is 250 [µm] and the velocity is 16 [m/s], from splashing under microgravity condition, whereas splashes may occur at the surface of the droplet collector in the event that a nonuniform droplet stream collides against it.

Dynamic analysis of the large deployable reflector

NASA Technical Reports Server (NTRS)

Calleson, Robert E.; Scott, A. Don

1987-01-01

The Large Deployable Reflector (LDR) is to be an astronomical observatory orbiting above Earth's obscuring atmosphere and operating in the spectral range between 30 microns and 1000 microns wavelength. The LDR will be used to study such astronomical phenomena as stellar and galactic formation, cosmology, and planetary atmospheres. The LDR will be the first observatory to be erected and assembled in space. This distinction brings with it several major technological challenges such as the development of ultra-lightweight deployable mirrors, advanced mirror fabrication techniques, advanced structures, and control of vibrations due to various sources of excitation. The purpose of this analysis is to provide an assessment of the vibrational response due to secondary mirror chopping and LDR slewing. The dynamic response of two 20-m LDR configurations was studied. Two mirror support configurations were investigated for the Ames concept, the first employs a six-strut secondary mirror support structure, while the second uses a triple-bipod support design. All three configurations were modeled using a tetrahedral truss design for the primary mirror support structure. Response resulting from secondary mirror chopping was obtained for the two Ames configurations, and the response of the primary mirror from slewing was obtained for all three configurations.

LDR: A submillimeter great observatory

NASA Astrophysics Data System (ADS)

Wilson, Robert

1990-12-01

The Large Deployable Reflector (LDR), a high Earth orbit free flying 10 to 20 m diameter deployable telescope, is described. The LDR is intended for use throughout the submillimeter band, using imaging receivers with unprecedented sensitivity and angular resolution. Its mission is to produce pictures of line emission regions in the solar neighborhood, in nearby galaxies and in objects at the edge of the known galaxy distribution. It is predicted to be an ideal instrument for exploring the first galaxies and protogalaxies as the submillimeter cooling lines should light up as soon as metals form.

Comparative study of late rectal toxicity in prostate cancer patients treated with low-dose-rate brachytherapy: With or without supplemental external beam radiotherapy.

PubMed

Serrano, Nicholas; Moghanaki, Drew; Asher, David; Karlin, Jeremy; Schutzer, Matthew; Chang, Michael; Hagan, Michael P

2016-01-01

Supplemental external beam radiation therapy (sEBRT) is often prescribed in men undergoing low-dose-rate (LDR) brachytherapy. A population of patients was analyzed to assess the effect of sEBRT on late rectal toxicity. It was hypothesized that sEBRT + LDR would be associated with a higher risk of late rectal toxicity. This retrospective cohort study examined LDR brachytherapy patients, treated with or without sEBRT, with a minimum of 5-year followup. Longitudinal assessments were evaluated using the computerized patient record system. The Kaplan-Meier method was used for analysis. Median followup was 7.5 years for 245 patients from 2004 to 2007. sEBRT was administered to 33.5%. Followup beyond 5 years was available for 89%. Overall rates of Grade ≥2 and ≥3 rectal toxicities were 6.9% and 2.9%, respectively. The risk of Grade ≥2 rectal toxicity was 2.8-fold higher for patients receiving sEBRT (95% confidence interval: 1.1-7.2; p = 0.02). The risk of Grade ≥3 rectal toxicity was 11.9-fold higher for patients who received sEBRT (1.5-97.4, 95% confidence interval; p = 0.003). Six of seven patients with a Grade ≥3 rectal toxicity received sEBRT, including one who required an abdominoperineal resection. Median post-LDR D90, V150, V200, and R100 values were 103.3%, 59.4%, 30.1%, and 0.5 cc. In a cohort of LDR brachytherapy patients with high rates of followup, sEBRT + LDR was associated with significantly higher risk of Grade ≥2 and ≥3 late rectal toxicity. This analysis supports previous findings and maintains concern about the supplemental use of external beam radiation therapy with LDR brachytherapy while its benefit for tumor control has yet to be prospectively validated. Published by Elsevier Inc.

Pancreatic β-Cell Dysfunction in Diet-Induced Obese Mice: Roles of AMP-Kinase, Protein Kinase Cε, Mitochondrial and Cholesterol Metabolism, and Alterations in Gene Expression

PubMed Central

Pepin, Émilie; Al-Mass, Anfal; Attané, Camille; Zhang, Kezhuo; Lamontagne, Julien; Lussier, Roxane; Madiraju, S. R. Murthy; Joly, Erik; Ruderman, Neil B.; Sladek, Robert; Prentki, Marc; Peyot, Marie-Line

2016-01-01

Diet induced obese (DIO) mice can be stratified according to their weight gain in response to high fat diet as low responders (LDR) and high responders (HDR). This allows the study of β-cell failure and the transitions to prediabetes (LDR) and early diabetes (HDR). C57BL/6N mice were fed for 8 weeks with a normal chow diet (ND) or a high fat diet and stratified as LDR and HDR. Freshly isolated islets from ND, LDR and HDR mice were studied ex-vivo for mitochondrial metabolism, AMPK activity and signalling, the expression and activity of key enzymes of energy metabolism, cholesterol synthesis, and mRNA profiling. Severely compromised glucose-induced insulin secretion in HDR islets, as compared to ND and LDR islets, was associated with suppressed AMP-kinase activity. HDR islets also showed reduced acetyl-CoA carboxylase activity and enhanced activity of 3-hydroxy-3-methylglutaryl-CoA reductase, which led respectively to elevated fatty acid oxidation and increased cholesterol biosynthesis. HDR islets also displayed mitochondrial membrane hyperpolarization and reduced ATP turnover in the presence of elevated glucose. Expression of protein kinase Cε, which reduces both lipolysis and production of signals for insulin secretion, was elevated in DIO islets. Genes whose expression increased or decreased by more than 1.2-fold were minor between LDR and ND islets (17 differentially expressed), but were prominent between HDR and ND islets (1508 differentially expressed). In HDR islets, particularly affected genes were related to cell cycle and proliferation, AMPK signaling, mitochondrial metabolism and cholesterol metabolism. In conclusion, chronically reduced AMPK activity, mitochondrial dysfunction, elevated cholesterol biosynthesis in islets, and substantial alterations in gene expression accompany β-cell failure in HDR islets. The β-cell compensation process in the prediabetic state (LDR) is largely independent of transcriptional adaptive changes, whereas the transition to early diabetes (HDR) is associated with major alterations in gene expression. PMID:27043434

Development of a PCR/LDR/flow-through hybridization assay using a capillary tube, probe DNA-immobilized magnetic beads and chemiluminescence detection.

PubMed

Hommatsu, Manami; Okahashi, Hisamitsu; Ohta, Keisuke; Tamai, Yusuke; Tsukagoshi, Kazuhiko; Hashimoto, Masahiko

2013-01-01

A polymerase chain reaction (PCR)/ligase detection reaction (LDR)/flow-through hybridization assay using chemiluminescence (CL) detection was developed for analyzing point mutations in gene fragments with high diagnostic value for colorectal cancers. A flow-through hybridization format using a capillary tube, in which probe DNA-immobilized magnetic beads were packed, provided accelerated hybridization kinetics of target DNA (i.e. LDR product) to the probe DNA. Simple fluid manipulations enabled both allele-specific hybridization and the removal of non-specifically bound DNA in the wash step. Furthermore, the use of CL detection greatly simplified the detection scheme, since CL does not require a light source for excitation of the fluorescent dye tags on the LDR products. Preliminary results demonstrated that this analytical system could detect both homozygous and heterozygous mutations, without the expensive instrumentation and cumbersome procedures required by conventional DNA microarray-based methods.

Additive protection by LDR and FGF21 treatment against diabetic nephropathy in type 2 diabetes model.

PubMed

Shao, Minglong; Yu, Lechu; Zhang, Fangfang; Lu, Xuemian; Li, Xiaokun; Cheng, Peng; Lin, Xiufei; He, Luqing; Jin, Shunzi; Tan, Yi; Yang, Hong; Zhang, Chi; Cai, Lu

2015-07-01

The onset of diabetic nephropathy (DN) is associated with both systemic and renal changes. Fibroblast growth factor (FGF)-21 prevents diabetic complications mainly by improving systemic metabolism. In addition, low-dose radiation (LDR) protects mice from DN directly by preventing renal oxidative stress and inflammation. In the present study, we tried to define whether the combination of FGF21 and LDR could further prevent DN by blocking its systemic and renal pathogeneses. To this end, type 2 diabetes was induced by feeding a high-fat diet for 12 wk followed by a single dose injection of streptozotocin. Diabetic mice were exposed to 50 mGy LDR every other day for 4 wk with and without 1.5 mg/kg FGF21 daily for 8 wk. The changes in systemic parameters, including blood glucose levels, lipid profiles, and insulin resistance, as well as renal pathology, were examined. Diabetic mice exhibited renal dysfunction and pathological abnormalities, all of which were prevented significantly by LDR and/or FGF21; the best effects were observed in the group that received the combination treatment. Our studies revealed that the additive renal protection conferred by the combined treatment against diabetes-induced renal fibrosis, inflammation, and oxidative damage was associated with the systemic improvement of hyperglycemia, hyperlipidemia, and insulin resistance. These results suggest that the combination treatment with LDR and FGF21 prevented DN more efficiently than did either treatment alone. The mechanism behind these protective effects could be attributed to the suppression of both systemic and renal pathways. Copyright © 2015 the American Physiological Society.

Additive protection by LDR and FGF21 treatment against diabetic nephropathy in type 2 diabetes model

PubMed Central

Shao, Minglong; Yu, Lechu; Zhang, Fangfang; Lu, Xuemian; Li, Xiaokun; Cheng, Peng; Lin, Xiufei; He, Luqing; Jin, Shunzi; Tan, Yi; Yang, Hong; Cai, Lu

2015-01-01

The onset of diabetic nephropathy (DN) is associated with both systemic and renal changes. Fibroblast growth factor (FGF)-21 prevents diabetic complications mainly by improving systemic metabolism. In addition, low-dose radiation (LDR) protects mice from DN directly by preventing renal oxidative stress and inflammation. In the present study, we tried to define whether the combination of FGF21 and LDR could further prevent DN by blocking its systemic and renal pathogeneses. To this end, type 2 diabetes was induced by feeding a high-fat diet for 12 wk followed by a single dose injection of streptozotocin. Diabetic mice were exposed to 50 mGy LDR every other day for 4 wk with and without 1.5 mg/kg FGF21 daily for 8 wk. The changes in systemic parameters, including blood glucose levels, lipid profiles, and insulin resistance, as well as renal pathology, were examined. Diabetic mice exhibited renal dysfunction and pathological abnormalities, all of which were prevented significantly by LDR and/or FGF21; the best effects were observed in the group that received the combination treatment. Our studies revealed that the additive renal protection conferred by the combined treatment against diabetes-induced renal fibrosis, inflammation, and oxidative damage was associated with the systemic improvement of hyperglycemia, hyperlipidemia, and insulin resistance. These results suggest that the combination treatment with LDR and FGF21 prevented DN more efficiently than did either treatment alone. The mechanism behind these protective effects could be attributed to the suppression of both systemic and renal pathways. PMID:25968574

Emesis as a Screening Diagnostic for Low Dose Rate (LDR) Total Body Radiation Exposure.

PubMed

Camarata, Andrew S; Switchenko, Jeffrey M; Demidenko, Eugene; Flood, Ann B; Swartz, Harold M; Ali, Arif N

2016-04-01

Current radiation disaster manuals list the time-to-emesis (TE) as the key triage indicator of radiation dose. The data used to support TE recommendations were derived primarily from nearly instantaneous, high dose-rate exposures as part of variable condition accident databases. To date, there has not been a systematic differentiation between triage dose estimates associated with high and low dose rate (LDR) exposures, even though it is likely that after a nuclear detonation or radiologic disaster, many surviving casualties would have received a significant portion of their total exposure from fallout (LDR exposure) rather than from the initial nuclear detonation or criticality event (high dose rate exposure). This commentary discusses the issues surrounding the use of emesis as a screening diagnostic for radiation dose after LDR exposure. As part of this discussion, previously published clinical data on emesis after LDR total body irradiation (TBI) is statistically re-analyzed as an illustration of the complexity of the issue and confounding factors. This previously published data includes 107 patients who underwent TBI up to 10.5 Gy in a single fraction delivered over several hours at 0.02 to 0.04 Gy min. Estimates based on these data for the sensitivity of emesis as a screening diagnostic for the low dose rate radiation exposure range from 57.1% to 76.6%, and the estimates for specificity range from 87.5% to 99.4%. Though the original data contain multiple confounding factors, the evidence regarding sensitivity suggests that emesis appears to be quite poor as a medical screening diagnostic for LDR exposures.

Exopolysaccharides from Lactobacillus delbrueckii OLL1073R-1 modulate innate antiviral immune response in porcine intestinal epithelial cells.

PubMed

Kanmani, Paulraj; Albarracin, Leonardo; Kobayashi, Hisakazu; Iida, Hikaru; Komatsu, Ryoya; Humayun Kober, A K M; Ikeda-Ohtsubo, Wakako; Suda, Yoshihito; Aso, Hisashi; Makino, Seiya; Kano, Hiroshi; Saito, Tadao; Villena, Julio; Kitazawa, Haruki

2018-01-01

Previous studies demonstrated that the extracellular polysaccharides (EPSs) produced by Lactobacillus delbrueckii OLL1073R-1 (LDR-1) improve antiviral immunity, especially in the systemic and respiratory compartments. However, it was not studied before whether those EPSs are able to beneficially modulate intestinal antiviral immunity. In addition, LDR-1-host interaction has been evaluated mainly with immune cells while its interaction with intestinal epithelial cells (IECs) was not addressed before. In this work, we investigated the capacity of EPSs from LDR-1 to modulate the response of porcine IECs (PIE cells) to the stimulation with the Toll-like receptor (TLR)-3 agonist poly(I:C) and the role of TLR2, TLR4, and TLR negative regulators in the immunoregulatory effect. We showed that innate immune response triggered by TLR3 activation in porcine IECs was differentially modulated by EPS from LDR-1. EPSs treatment induced an increment in the expression of interferon (IFN)-α and IFN-β in PIE cells after the stimulation with poly(I:C) as well as the expression of the antiviral factors MxA and RNase L. Those effects were related to the reduced expression of A20 in EPS-treated PIE cells. EPS from LDR-1 was also able to reduce the expression of IL-6 and proinflammatory chemokines. Although further in vivo studies are needed, our results suggest that these EPSs or a yogurt fermented with LDR-1 have potential to improve intestinal innate antiviral response and protect against intestinal viruses. Copyright © 2017 Elsevier Ltd. All rights reserved.

Elastic properties of muscle-tendon complex in long-distance runners.

PubMed

Kubo, K; Kanehisa, H; Kawakami, Y; Fukunaga, T

2000-02-01

The purpose of this study was to investigate the elastic properties of muscle-tendon complex (MTC) in knee extensor muscles and the capacity for elastic energy utilization in long-distance runners (LDR) by comparing with data obtained from untrained individuals (CON). The elongation (L) of the tendon and aponeurosis of vastus lateralis muscle during isometric knee extension was determined by real-time brightness mode ultrasonography, while the subjects developed a gradually increasing torque from 0 (relaxed) to maximal effort (MVC) within 7 s. In addition, performances in two kinds of maximal vertical jumps, i.e. squatting (SJ) and counter-movement jumps (CMJ), were measured. The relationship between L muscle and force (F) was curvilinear and consisted of an initial region (toe region), characterized by a large increase in L with increasing F, immediately followed by a linear region. The slope of the regression equation for the L-F relationship in the range 50%-100% of MVC was defined as an index of MTC compliance, where the rate of the changes in L to that in muscle F at every 10% of MVC became almost constant. The maximal L (Lmax) and MTC compliance were significantly lower in LDR than in CON: 29.9 (SD 3.9) mm in LDR compared to 33.3 (SD 5.5) mm in CON for Lmax and 1.55 (SD 0.25) x 10(-2) mm.N-1 in LDR compared to 1.88 (SD 0.82) x 10(-2) mm.N-1 in CON for MTC compliance. Also, LDR showed significantly less elastic energy absorption (Ee) than CON, defined as the area below the L-F relationship curve from 0 to 100% of MVC. Not only jump heights but also the differences between the heights in SJ and CMJ, expressed as the percentage of the height in SJ, were significantly lower in LDR than in CON. The augmentation with counter-movement was significantly correlated to either MTC compliance (r = 0.554, P < 0.05) or Ee (r = 0.563, P < 0.05). Thus, the present results would indicate that MTC of vastus lateralis muscle is less compliant and its potential for energy storage during MTS lengthening is lower in LDR than untrained individuals. These elastic profiles of vastus lateralis muscle in LDR may be associated with their lower performances during CMJ.

Is there any place for LDR brachytherapy for head and neck carcinomas in HDR era?

PubMed

Fijuth, Jacek

2009-03-01

In Poland, the classical LDR brachytherapy for head and neck carcinomas with Ir-192 wires or hairpins has completely disappeared some time ago after 30 years of successful clinical use. Can this technique be fully and safely replaced by HDR or PDR application? This option seems attractive because of new possibilities of 3D reconstruction and computer real-time treatment planning and optimization. However, in my opinion, long time is needed to get a clinical and scientific experience that has been accumulated for decades with the use of LDR technique.

Studies of low-mass star formation with the large deployable reflector

NASA Technical Reports Server (NTRS)

Hollenbach, D. J.; Tielens, Alexander G. G. M.

1984-01-01

Estimates are made of the far-infrared and submillimeter continuum and line emission from regions of low mass star formation. The intensity of this emission is compared with the sensitivity of the large deployable reflector (LDR), a large space telescope designed for this wavelength range. The proposed LDR is designed to probe the temperature, density, chemical structure, and the velocity field of the collapsing envelopes of these protostars. The LDR is also designed to study the accretion shocks on the cores and circumstellar disks of low-mass protostars, and to detect shock waves driven by protostellar winds.

Distinct biological effects of low-dose radiation on normal and cancerous human lung cells are mediated by ATM signaling

PubMed Central

Li, Wei; Zhao, Yuguang; Wen, Xue; Liang, Xinyue; Zhang, Xiaoying; Zhou, Lei; Hu, Jifan; Niu, Chao; Tian, Huimin; Han, Fujun; Chen, Xiao; Dong, Lihua; Cai, Lu; Cui, Jiuwei

2016-01-01

Low-dose radiation (LDR) induces hormesis and adaptive response in normal cells but not in cancer cells, suggesting its potential protection of normal tissue against damage induced by conventional radiotherapy. However, the underlying mechanisms are not well established. We addressed this in the present study by examining the role of the ataxia telangiectasia mutated (ATM) signaling pathway in response to LDR using A549 human lung adenocarcinoma cells and HBE135-E6E7 (HBE) normal lung epithelial cells. We found that LDR-activated ATM was the initiating event in hormesis and adaptive response to LDR in HBE cells. ATM activation increased the expression of CDK4/CDK6/cyclin D1 by activating the AKT/glycogen synthase kinase (GSK)-3β signaling pathway, which stimulated HBE cell proliferation. Activation of ATM/AKT/GSK-3β signaling also increased nuclear accumulation of nuclear factor erythroid 2-related factor 2, leading to increased expression of antioxidants, which mitigated cellular damage from excessive reactive oxygen species production induced by high-dose radiation. However, these effects were not observed in A549 cells. Thus, the failure to activate these pathways in A549 cells likely explains the difference between normal and cancer cells in terms of hormesis and adaptive response to LDR. PMID:27708248

A novel nonlinear damage resonance intermodulation effect for structural health monitoring

NASA Astrophysics Data System (ADS)

Ciampa, Francesco; Scarselli, Gennaro; Meo, Michele

2017-04-01

This paper is aimed at developing a theoretical model able to predict the generation of nonlinear elastic effects associated to the interaction of ultrasonic waves with the steady-state nonlinear response of local defect resonance (LDR). The LDR effect is used in nonlinear elastic wave spectroscopy to enhance the excitation of the material damage at its local resonance, thus to dramatically increase the vibrational amplitude of material nonlinear phenomena. The main result of this work is to prove both analytically and experimentally the generation of novel nonlinear elastic wave effects, here named as nonlinear damage resonance intermodulation, which correspond to a nonlinear intermodulation between the driving frequency and the LDR one. Beside this intermodulation effect, other nonlinear elastic wave phenomena such as higher harmonics of the input frequency and superharmonics of LDR frequency were found. The analytical model relies on solving the nonlinear equation of motion governing bending displacement under the assumption of both quadratic and cubic nonlinear defect approximation. Experimental tests on a damaged composite laminate confirmed and validated these predictions and showed that using continuous periodic excitation, the nonlinear structural phenomena associated to LDR could also be featured at locations different from the damage resonance. These findings will provide new opportunities for material damage detection using nonlinear ultrasounds.

PCR/LDR/capillary electrophoresis for detection of single-nucleotide differences between fetal and maternal DNA in maternal plasma.

PubMed

Yi, Ping; Chen, Zhuqin; Zhao, Yan; Guo, Jianxin; Fu, Huabin; Zhou, Yuanguo; Yu, Lili; Li, Li

2009-03-01

The discovery of fetal DNA in maternal plasma has opened up an approach for noninvasive diagnosis. We have now assessed the possibility of detecting single-nucleotide differences between fetal and maternal DNA in maternal plasma by polymerase chain reaction (PCR)/ligase detection reaction((LDR)/capillary electrophoresis. PCR/LDR/capillary electrophoresis was applied to detect the genotype of c.454-397T>gene (ESR1) from experimental DNA models of maternal plasma at different sensitivity levels and 13 maternal plasma samples.alphaC in estrogen receptor. (1) Our results demonstrated that the technique could discriminate low abundance single-nucleotide mutation with a mutant/normal allele ratio up to 1:10 000. (2) Examination of ESR1 c.454-397T>C genotypes by using the method of restriction fragment length analysis was performed in 25 pregnant women, of whom 13 pregnant women had homozygous genotypes. The c.454-397T>C genotypes of paternally inherited fetal DNA in maternal plasma of these 13 women were detected by PCR/LDR/capillary electrophoresis, which were accordant with the results of umbilical cord blood. PCR/LDR/capillary electrophoresis has very high sensitivity to distinguish low abundance single nucleotide differences and can discriminate point mutations and single-nucleotide polymorphisms(SNPs) of paternally inherited fetal DNA in maternal plasma.

The evolution of brachytherapy for prostate cancer.

PubMed

Zaorsky, Nicholas G; Davis, Brian J; Nguyen, Paul L; Showalter, Timothy N; Hoskin, Peter J; Yoshioka, Yasuo; Morton, Gerard C; Horwitz, Eric M

2017-06-30

Brachytherapy (BT), using low-dose-rate (LDR) permanent seed implantation or high-dose-rate (HDR) temporary source implantation, is an acceptable treatment option for select patients with prostate cancer of any risk group. The benefits of HDR-BT over LDR-BT include the ability to use the same source for other cancers, lower operator dependence, and - typically - fewer acute irritative symptoms. By contrast, the benefits of LDR-BT include more favourable scheduling logistics, lower initial capital equipment costs, no need for a shielded room, completion in a single implant, and more robust data from clinical trials. Prospective reports comparing HDR-BT and LDR-BT to each other or to other treatment options (such as external beam radiotherapy (EBRT) or surgery) suggest similar outcomes. The 5-year freedom from biochemical failure rates for patients with low-risk, intermediate-risk, and high-risk disease are >85%, 69-97%, and 63-80%, respectively. Brachytherapy with EBRT (versus brachytherapy alone) is an appropriate approach in select patients with intermediate-risk and high-risk disease. The 10-year rates of overall survival, distant metastasis, and cancer-specific mortality are >85%, <10%, and <5%, respectively. Grade 3-4 toxicities associated with HDR-BT and LDR-BT are rare, at <4% in most series, and quality of life is improved in patients who receive brachytherapy compared with those who undergo surgery.

Large Deployable Reflector (LDR) thermal characteristics

NASA Technical Reports Server (NTRS)

Miyake, R. N.; Wu, Y. C.

1988-01-01

The thermal support group, which is part of the lightweight composite reflector panel program, developed thermal test and analysis evaluation tools necessary to support the integrated interdisciplinary analysis (IIDA) capability. A detailed thermal mathematical model and a simplified spacecraft thermal math model were written. These models determine the orbital temperature level and variation, and the thermally induced gradients through and across a panel, for inclusion in the IIDA.

Final Report - Epigenetics of low dose radiation effects in an animal model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kovalchuk, Olga

This project sought mechanistic understanding of the epigenetic response of tissues as well as the consequences of those responses, when induced by low dose irradiation in a well-established model system (mouse). Based on solid and extensive preliminary data we investigated the molecular epigenetic mechanisms of in vivo radiation responses, particularly – effects of low, occupationally relevant radiation exposures on the genome stability and adaptive response in mammalian tissues and organisms. We accumulated evidence that low dose irradiation altered epigenetic profiles and impacted radiation target organs of the exposed animals. The main long-term goal was to dissect the epigenetic basis ofmore » induction of the low dose radiation-induced genome instability and adaptive response and the specific fundamental roles of epigenetic changes (i.e. DNA methylation, histone modifications and miRNAs) in their generation. We hypothesized that changes in global and regional DNA methylation, global histone modifications and regulatory microRNAs played pivotal roles in the generation and maintenance low-dose radiation-induced genome instability and adaptive response. We predicted that epigenetic changes influenced the levels of genetic rearrangements (transposone reactivation). We hypothesized that epigenetic responses from low dose irradiation were dependent on exposure regimes, and would be greatest when organisms are exposed in a protracted/fractionated manner: fractionated exposures > acute exposures. We anticipated that the epigenetic responses were correlated with the gene expression levels. Our immediate objectives were: • To investigate the exact nature of the global and locus-specific DNA methylation changes in the LDR exposed cells and tissues and dissect their roles in adaptive response • To investigate the roles of histone modifications in the low dose radiation effects and adaptive response • To dissect the roles of regulatory microRNAs and their targets in low dose radiation effects and adaptive response • To correlate the levels of epigenetic changes with genetic rearrangement levels and gene expression patterns. In sum, we determined the precise global and locus-specific DNA methylation patterns in the LDR-exposed cells and tissues of mice, and to correlated DNA methylation changes with the gene expression patterns and manifestations of genome instability. We also determined the alterations of global histone modification pattern in the LDR exposed tissues. Additionally, we established the nature of microRNAome changes in the LDR exposed tissue. In this study we for the first time found that LDR exposure caused profound tissue-specific epigenetic changes in the exposed tissues. We established that LDR exposure affect methylation of repetitive elements in the murine genome, causes changes in histone methylation, acetylation and phosphorylation. Importantly, we found that LDR causes profound and persistent effects on small RNA profiles and gene expression, and that miRNAs are excellent biomarkers of LDR exposure. Furthermore, we extended our analysis and studied LDR effects in rat tissues and human tissues and cell lines. There we also analyzed LDR-induced gene expression, DNA methylation and miRNA changes. Our datasets laid foundation for several new research projects aimed to understand molecular underpinnings of low dose radiation responses, and biological repercussions of low dose radiation effects and radiation carcinogenesis.« less

LDR brachytherapy: can low dose rate hypersensitivity from the "inverse" dose rate effect cause excessive cell killing to peripherial connective tissues and organs?

PubMed

Leonard, B E; Lucas, A C

2009-02-01

Examined here are the possible effects of the "inverse" dose rate effect (IDRE) on low dose rate (LDR) brachytherapy. The hyper-radiosensitivity and induced radioresistance (HRS/IRR) effect benefits cell killing in radiotherapy, and IDRE and HRS/IRR seem to be generated from the same radioprotective mechanisms. We have computed the IDRE excess cell killing experienced in LDR brachytherapy using permanent seed implants. We conclude, firstly, that IDRE is a dose rate-dependent manifestation of HRS/IRR. Secondly, the presence of HRS/IRR or IDRE in a cell species or tissue must be determined by direct dose-response measurements. Thirdly, a reasonable estimate is that 50-80% of human adjoining connective and organ tissues experience IDRE from permanent implanted LDR brachytherapy. If IDRE occurs for tissues at point A for cervical cancer, the excess cell killing will be about a factor of 3.5-4.0 if the initial dose rate is 50-70 cGy h(-1). It is greater for adjacent tissues at lower dose rates and higher for lower initial dose rates at point A. Finally, higher post-treatment complications are observed in LDR brachytherapy, often for unknown reasons. Some of these are probably a result of IDRE excess cell killing. Measurements of IDRE need be performed for connective and adjacent organ tissues, i.e. bladder, rectum, urinary tract and small bowels. The measured dose rate-dependent dose responses should extended to <10 cGy h(-1) and involve multiple patients to detect patient variability. Results may suggest a preference for high dose rate brachytherapy or LDR brachytherapy without permanent retention of the implant seeds (hence the dose rates in peripheral tissues and organs remain above IDRE thresholds).

The role of nitric oxide radicals in removal of hyper-radiosensitivity by priming irradiation

PubMed Central

Edin, Nina Jeppesen; Sandvik, Joe Alexander; Vollan, Hilde Synnøve; Reger, Katharina; Görlach, Agnes; Pettersen, Erik Olai

2013-01-01

In this study, a mechanism in which low-dose hyper-radiosensitivity (HRS) is permanently removed, induced by low-dose-rate (LDR) (0.2–0.3 Gy/h for 1 h) but not by high-dose-rate priming (0.3 Gy at 40 Gy/h) was investigated. One HRS-negative cell line (NHIK 3025) and two HRS-positive cell lines (T-47D, T98G) were used. The effects of different pretreatments on HRS were investigated using the colony assay. Cell-based ELISA was used to measure nitric oxide synthase (NOS) levels, and microarray analysis to compare gene expression in primed and unprimed cells. The data show how permanent removal of HRS, previously found to be induced by LDR priming irradiation, can also be induced by addition of nitric oxide (NO)-donor DEANO combined with either high-dose-rate priming or exposure to prolonged cycling hypoxia followed by reoxygenation, a treatment not involving radiation. The removal of HRS appears not to involve DNA damage induced during priming irradiation as it was also induced by LDR irradiation of cell-conditioned medium without cells present. The permanent removal of HRS in LDR-primed cells was reversed by treatment with inducible nitric oxide synthase (iNOS) inhibitor 1400W. Furthermore, 1400W could also induce HRS in an HRS-negative cell line. The data suggest that LDR irradiation for 1 h, but not 15 min, activates iNOS, and also that sustained iNOS activation is necessary for the permanent removal of HRS by LDR priming. The data indicate that nitric oxide production is involved in the regulatory processes determining cellular responses to low-dose-rate irradiation. PMID:23685670

LDR reverses DDP resistance in ovarian cancer cells by affecting ERCC-1, Bcl-2, Survivin and Caspase-3 expressions.

PubMed

Ju, Xingyan; Yu, Hongsheng; Liang, Donghai; Jiang, Tao; Liu, Yuanwei; Chen, Ling; Dong, Qing; Liu, Xiaoran

2018-06-01

Ovarian cancer is the most frequent cause of death resulting from malignant gynecological tumors. After surgical intervention, cisplatin (DDP) is a major chemotherapy drug for ovarian cancer, but the ovarian cancer cells tend to develop DDP resistance in the clinical setting. Tumor cells are sensitive to low-dose radiation (LDR). However, how the LDR therapy improves the effects of chemotherapy drugs on ovarian cancer is not well understood. This study aimed to explore this issue. The SKOV3/DDP cells were divided into 3 groups, including low-dose group, conventional-dose group, and control group (no radiation). Cell counting kit-8 assay was performed to measure cell proliferation. Flow cytometric analysis was then utilized to quantify the apoptosis with classical Annexin V/propidium iodide co-staining. And Real-time quantitative PCR and western blot were eventually used to analyze the mRNA and protein levels of excision repair cross complementing-group 1 (ERCC1), B-cell lymphoma 2 (Bcl-2), Survivin and Caspase-3, respectively. The IC50 value of DDP in the low-dose group was significantly lower compared with the other two groups. Compared with the conventional-dose group and control group, LDR treatment resulted in significantly more apoptosis. Besides, LDR treatment significantly decreased the mRNA and protein expression of ERCC1, Bcl-2, and Survivin, and enhanced the mRNA and protein expression of Caspase-3 compared with the other two groups. LDR reversed DDP resistance in SKOV3/DDP cells possibly by suppressing ERCC1, Bcl-2, and Survivin expressions, and increasing Caspase-3 expression. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

High- and low-dose-rate intraoperative radiotherapy for thoracic malignancies resected with close or positive margins.

PubMed

Fleming, Christopher; Rimner, Andreas; Cohen, Gil'ad N; Woo, Kaitlin M; Zhang, Zhigang; Rosenzweig, Kenneth E; Alektiar, Kaled M; Zelefsky, Michael J; Bains, Manjit S; Wu, Abraham J

2016-01-01

Local recurrence is a significant problem after surgical resection of thoracic tumors. As intraoperative radiotherapy (IORT) can deliver radiation directly to the threatened margin, we have used this therapy in an attempt to reduce local recurrence, using high-dose-rate (HDR) as well as low-dose-rate (LDR) techniques. We performed a retrospective review of patients undergoing LDR ((125)I) mesh placement or HDR ((192)Ir) afterloading therapy during lung tumor resection between 2001 and 2013 at our institution. Competing risks methods were used to estimate the cumulative incidence of local failure. We also assessed possible predictive factors of local failure. Fifty-nine procedures (41 LDR and 18 HDR) were performed on 58 patients. Median follow-up was 55.1 months. Cumulative incidence of local failure at 1, 2, and 3 years was 28.5%, 34.2%, and 34.2%, respectively. Median overall survival was 39.9 months. There was no significant difference in local failure according to margin status, HDR vs. LDR, use of adjuvant external beam radiotherapy, or metastatic vs. primary tumor. Two patients (3.4%) experienced Grade 3+ toxicities likely related to brachytherapy. Additionally, 7 patients experienced Grade 3+ postsurgical complications unlikely related to brachytherapy. IORT is associated with good local control after resection of thoracic tumors otherwise at very high risk for local recurrence. There is a low incidence of severe toxicity attributable to brachytherapy. HDR-IORT appears to have equivalent outcomes to LDR-IORT. HDR or LDR-IORT can, therefore, be considered in situations where the oncologic completeness of thoracic tumor resection is in doubt. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

Assessment of Contaminant Exposure and Effects on Ospreys Nesting along the Lower Duwamish River, Washington, 2006-07

USGS Publications Warehouse

Johnson, Branden L.; Henny, Charles J.; Kaiser, James L.; Davis, Jay W.; Schulz, Edmund P.

2009-01-01

We evaluated the effects of contaminants on osprey (Pandion haliaetus) nesting along the lower Duwamish River (LDR), Washington, and used the upper reach of the Willamette River (WR), Oregon, as a reference site. Osprey eggs and nestling blood (plasma) were collected at nests along the LDR (11 eggs, 7 plasmas) and WR (10 eggs, 6 plasmas) in 2006-07 and analyzed for contaminants. Additionally, hematology and serum chemistries were determined in the blood/plasma samples of nestlings (about 35-45 days old) and were used as potential indicators of stress induced by contaminant exposure. Detailed foraging information for ospreys nesting along the LDR was collected and evaluated to better understand contaminant profiles observed in the eggs and plasma. Additional residue data from 26 osprey eggs collected and analyzed in 2002-03 from nests along the LDR, Snohomish River Estuary (SRE) and Lake Washington (LW) in the Puget Sound (PS) region also were evaluated.

Diffraction, chopping, and background subtraction for LDR

NASA Technical Reports Server (NTRS)

Wright, Edward L.

1988-01-01

The Large Deployable Reflector (LDR) will be an extremely sensitive infrared telescope if the noise due to the photons in the large thermal background is the only limiting factor. For observations with a 3 arcsec aperture in a broadband at 100 micrometers, a 20-meter LDR will emit 10(exp 12) per second, while the photon noise limited sensitivity in a deep survey observation will be 3,000 photons per second. Thus the background subtraction has to work at the 1 part per billion level. Very small amounts of scattered or diffracted energy can be significant if they are modulated by the chopper. The results are presented for 1-D and 2-D diffraction calculations for the lightweight, low-cost LDR concept that uses an active chopping quaternary to correct the wavefront errors introduced by the primary. Fourier transforms were used to evaluate the diffraction of 1 mm waves through this system. Unbalanced signals due to dust and thermal gradients were also studied.

Urethral toxicity after LDR brachytherapy: experience in Japan.

PubMed

Tanaka, Nobumichi; Asakawa, Isao; Hasegawa, Masatoshi; Fujimoto, Kiyohide

2015-01-01

Urinary toxicity is common after low-dose-rate (LDR) brachytherapy, and the resolution of urinary toxicity is a concern. In particular, urinary frequency is the most common adverse event among the urinary toxicities. We have previously reported that approximately 70% of patients experience urinary frequency during the first 6 months after seed implantation. Most urinary adverse events were classified as Grade 1, and Grade 2 or higher adverse events were rare. The incidence of urinary retention was approximately 2-4%. A high International Prostate Symptom Score before seed implantation was an independent predictor of acute urinary toxicity of Grade 2 or higher. Several previous reports from the United States also supported this trend. In Japan, LDR brachytherapy was legally approved in 2003. A nationwide prospective cohort study entitled Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 Seed Implantation was initiated in July 2005. It is an important issue to limit urinary toxicities in patients who undergo LDR brachytherapy. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

Prostate-specific antigen nadir within 12 months as an early surrogate marker of biochemical failure and distant metastasis after low-dose-rate brachytherapy or external beam radiotherapy for localized prostate cancer.

PubMed

Nishimura, Shuichi; Ohashi, Toshio; Momma, Tetsuo; Sakayori, Masanori; Eriguchi, Takahisa; Tanaka, Tomoki; Yamashita, Shoji; Kosaka, Takeo; Oya, Mototsugu; Shigematsu, Naoyuki

2018-05-01

Prostate-specific antigen nadir (nPSA) after radiotherapy for localized prostate cancer has been investigated as a predictor. However, nPSA usually requires several years, limiting its clinical utility. We investigated the significance of nPSA within 12 months (nPSA12) after low-dose-rate prostate brachytherapy (LDR-PB) or external beam radiotherapy (EBRT) on treatment outcomes. Between 2006 and 2014, 663 patients with prostate cancer were treated with LDR-PB or EBRT at two institutions. Four hundred and seventy-four men received LDR-PB and 189 men received EBRT, without androgen deprivation therapy. The Kaplan-Meier method was used for biochemical failure (BF)-free survival (BFFS) and distant metastasis (DM)-free survival (DMFS) analyses, and multivariable Cox regression analysis was performed. The median follow-up was 61.3 months. The median nPSA12 in the LDR-PB and EBRT cohorts was 0.7 and 1.0 ng/mL, respectively. The 7-year BFFS and DMFS rates in LDR-PB patients with nPSA12 ≤ 0.7 ng/mL were 99.1% and 99.5%, respectively; when nPSA12 was >0.7 ng/mL, they were 90.2% and 94.8%, respectively. In EBRT patients with nPSA12 ≤ 1.0 ng/mL, BFFS and DMFS rates were 85.4% and 98.5%, respectively; when nPSA12 was >1.0 ng/mL, they were 67.1% and 87.2%, respectively. nPSA12 was an independent predictor of BF and DM in both cohorts (LDR-PB, P = 0.004 and 0.020, respectively; EBRT, P = 0.005 and 0.041, respectively). The nPSA12 after LDR-PB or EBRT is significantly associated with treatment outcomes of prostate cancer. Higher nPSA12 may identify patients at high risk of relapse who might benefit from salvage treatment. © 2018 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Commitment Predictors: Long-Distance versus Geographically Close Relationships

ERIC Educational Resources Information Center

Pistole, M. Carole; Roberts, Amber; Mosko, Jonathan E.

2010-01-01

In this web-based study, the authors examined long-distance relationships (LDRs) and geographically close relationships (GCRs). Two hierarchical multiple regressions (N = 138) indicated that attachment predicted LDR and GCR commitment in Step 1. Final equations indicated that high satisfaction and investments predicted LDR commitment, whereas low…

Local defect resonance for sensitive non-destructive testing

NASA Astrophysics Data System (ADS)

Adebahr, W.; Solodov, I.; Rahammer, M.; Gulnizkij, N.; Kreutzbruck, M.

2016-02-01

Ultrasonic wave-defect interaction is a background of ultrasound activated techniques for imaging and non-destructive testing (NDT) of materials and industrial components. The interaction, primarily, results in acoustic response of a defect which provides attenuation and scattering of ultrasound used as an indicator of defects in conventional ultrasonic NDT. The derivative ultrasonic-induced effects include e.g. nonlinear, thermal, acousto-optic, etc. responses also applied for NDT and defect imaging. These secondary effects are normally relatively inefficient so that the corresponding NDT techniques require an elevated acoustic power and stand out from conventional ultrasonic NDT counterparts for their specific instrumentation particularly adapted to high-power ultrasonic. In this paper, a consistent way to enhance ultrasonic, optical and thermal defect responses and thus to reduce an ultrasonic power required is suggested by using selective ultrasonic activation of defects based on the concept of local defect resonance (LDR). A strong increase in vibration amplitude at LDR enables to reliably detect and visualize the defect as soon as the driving ultrasonic frequency is matched to the LDR frequency. This also provides a high frequency selectivity of the LDR-based imaging, i.e. an opportunity of detecting a certain defect among a multitude of other defects in material. Some examples are shown how to use LDR in non-destructive testing techniques, like vibrometry, ultrasonic thermography and shearography in order to enhance the sensitivity of defect visualization.

Development of a PCR/LDR/capillary electrophoresis assay with potential for the detection of a beta-thalassemia fetal mutation in maternal plasma.

PubMed

Yi, Ping; Chen, Zhuqin; Yu, Lili; Zheng, Yingru; Liu, Guodong; Xie, Haichang; Zhou, Yuanguo; Zheng, Xiuhui; Han, Jian; Li, Li

2010-08-01

Analysis of fetal DNA in maternal plasma has recently been introduced for non-invasive prenatal diagnosis. We have now investigated the feasibility of polymerase chain reaction (PCR)/ligase detection reaction (LDR)/capillary electrophoresis for the detection of fetal point mutations, such as the beta-thalassemia mutation, IVS2 654(C --> T), in maternal plasma DNA. The sensitivity of LDR/capillary electrophoresis was examined by quantifying the mutant PCR products in the presence of a vast excess of non-mutant competitor template, a situation that mimics the detection of rare fetal mutations in the presence of excess maternal DNA. PCR/LDR/capillary electrophoresis was applied to detect the mutation, IVS2 654(C --> T), in an experimental model at different sensitivity levels and from 10 maternal plasma samples. Our results demonstrated that this approach to detect a low abundance IVS2 654(C --> T) mutation achieved a sensitivity of approximately 1:10,000. The approach was applied to maternal plasma DNA to detect the paternally inherited fetal IVS2 654(C --> T) mutation, and the results were equivalent to those obtained by PCR/reverse dot blot of amniotic fluid cell DNA. PCR/LDR/capillary electrophoresis has a very high sensitivity that can distinguish low abundance single nucleotide differences and can detect paternally inherited fetal point mutations in maternal plasma.

The effects of proton radiation on the prothrombin and partial thromboplastin times of irradiated ferrets

PubMed Central

Krigsfeld, Gabriel S.; Sanzari, Jenine K.; Kennedy, Ann R.

2013-01-01

Purpose To determine whether proton radiation affects coagulation. Material and methods Ferrets were exposed to solar particle event-like proton radiation at doses of 0, 25, 100, or 200 centigray (cGy), and dose rates of 50 cGy/minute (high dose rate or HDR) or 50 cGy/hour (low dose rate or LDR). Plasma was isolated from blood collected prior to radiation exposure and at 3–7 h post-radiation. Prothrombin time (PT) assays and activated partial thromboplastin time (aPTT) assays were performed as were mixing studies to determine the coagulation factors involved. Results HDR and LDR exposure led to statistically significant increases in PT values. It was determined that the HDR-induced increase in PT was due to Factor VII, while Factors II, V, and VII contributed to the LDR-induced increase in PT values. Only acute LDR exposure caused an increase in aPTT values, which remained elevated for 48 h post-irradiation (which was the latest time assayed in these studies). Mixing studies revealed that Factor IX contributed to the increased aPTT values. A majority of the animals exposed at the LDR had an International Normalized Ratio approaching or surpassing 2.0. Conclusions PT/aPTT assays resulted in increased clotting times due to different coagulation factors, indicating potential radiation-induced coagulopathy. PMID:22221163

Targeting MRS-Defined Dominant Intraprostatic Lesions with Inverse-Planned High Dose Rate Brachytherapy

DTIC Science & Technology

2008-06-01

brachytherapy treatment planning has been demonstrated. Using the inverse planning program IPSA , dose escalation of target regions with a higher tumor...algorithm (called IPSA ) was used to generate dose distributions for five different levels of DIL- boost, at least 110%, 120%, 130%, 140% and 150...and LDR, VI Last Generation Radiotherapy Course, São Paulo, Brazil, Oct. 19, 2006. Principles and Clinical Applications of IPSA ; Nucletron

Large Deployable Reflector Science and Technology Workshop. Volume 3: Systems and Technology Assessment. Introduction

NASA Technical Reports Server (NTRS)

1984-01-01

The Large Deployable Reflector (LDR), a proposed 20 m diameter telescope designed for infrared and submillimeter astronomical measurements from space, is discussed in terms of scientific purposes, capabilities, current status, and history of development. The LDR systems goals and functional/telescope requirements are enumerated.

Learning Design Research: Advancing Pedagogies in the Digital Age

ERIC Educational Resources Information Center

Dobozy, Eva

2013-01-01

Learning design research (LDR) is establishing itself as a separate and specialised field of educational research. Worldwide, technology-mediated learning experiences in higher and further education are on the increase. LDR investigates their success in providing effective outcomes-based and personalised learning experiences. This paper reports on…

Identification and Remediation of Learning Disability Subtypes: Preliminary Findings.

ERIC Educational Resources Information Center

Lyon, G. Reid

1985-01-01

Current literature on identification and instructional remediation of subtypes of learning-disabled readers (LDR) are reviewed. Preliminary findings suggest that not all LDR children manifest the same oral language, memory, and perceptual deficits that impede decoding accuracy and efficiency and all do not respond equally well (or poorly) to the…

Action Learning in Virtual Higher Education: Applying Leadership Theory

ERIC Educational Resources Information Center

Curtin, Joseph

2016-01-01

This paper reports the historical foundation of Northeastern University's course, LDR 6100: Developing Your Leadership Capability, a partial literature review of action learning (AL) and virtual action learning (VAL), a course methodology of LDR 6100 requiring students to apply leadership perspectives using VAL as instructed by the author,…

Action learning in virtual higher education: applying leadership theory.

PubMed

Curtin, Joseph

2016-05-03

This paper reports the historical foundation of Northeastern University's course, LDR 6100: Developing Your Leadership Capability, a partial literature review of action learning (AL) and virtual action learning (VAL), a course methodology of LDR 6100 requiring students to apply leadership perspectives using VAL as instructed by the author, questionnaire and survey results of students who evaluated the effectiveness of their application of leadership theories using VAL and insights believed to have been gained by the author administering VAL. Findings indicate most students thought applying leadership perspectives using AL was better than considering leadership perspectives not using AL. In addition as implemented in LDR 6100, more students evaluated VAL positively than did those who assessed VAL negatively.

LDR cryogenics

NASA Technical Reports Server (NTRS)

Nast, T.

1988-01-01

A brief summary from the 1985 Large Deployable Reflector (LDR) Asilomar 2 workshop of the requirements for LDR cryogenic cooling is presented. The heat rates are simply the sum of the individual heat rates from the instruments. Consideration of duty cycle will have a dramatic effect on cooling requirements. There are many possible combinations of cooling techniques for each of the three temperatures zones. It is clear that much further system study is needed to determine what type of cooling system is required (He-2, hybrid or mechanical) and what size and power is required. As the instruments, along with their duty cycles and heat rates, become better defined it will be possible to better determine the optimum cooling systems.

Big savings from small holes. [Liquid Droplet Radiator project for space vehicles

NASA Technical Reports Server (NTRS)

White, Alan

1989-01-01

The status and results to date of the NASA-Lewis/USAF Astronautics study of technology for large spacecraft heat-dissipation by means of liquid-droplet radiation (LDR) are discussed. The LDR concept uses a droplet generator to create billions of 200-micron droplets of a heatsink fluid which will cool through radiation into deep space as they fly toward a dropet collector. This exposure to the space environment entails the maintenance of vapor pressure as low as 10 to the -7th torr; the fluid must also be very stable chemically. While certain oils are good fluids for LDR use at low temperatures, higher-temperature heatsink fluids include Li, Sn, and Ga liquid metals.

Towards a robust HDR imaging system

NASA Astrophysics Data System (ADS)

Long, Xin; Zeng, Xiangrong; Huangpeng, Qizi; Zhou, Jinglun; Feng, Jing

2016-07-01

High dynamic range (HDR) images can show more details and luminance information in general display device than low dynamic image (LDR) images. We present a robust HDR imaging system which can deal with blurry LDR images, overcoming the limitations of most existing HDR methods. Experiments on real images show the effectiveness and competitiveness of the proposed method.

A new mode of acoustic NDT via resonant air-coupled emission

NASA Astrophysics Data System (ADS)

Solodov, Igor; Dillenz, Alexander; Kreutzbruck, Marc

2017-06-01

Resonant modes of non-destructive testing (NDT) which make use of local damage resonance (LDR) have been developed recently and demonstrated a significant increase in efficiency and sensitivity of hybrid inspection techniques by laser vibrometry, ultrasonic thermography, and shearography. In this paper, a new fully acoustic version of resonant NDT is demonstrated for defects in composite materials relevant to automotive and aviation applications. This technique is based on an efficient activation of defect vibrations by using a sonic/ultrasonic wave matched to a fundamental LDR frequency of the defect. On this condition, all points of the faulty area get involved in synchronous out-of-plane vibrations which produce a similar in-phase wave motion in ambient air. This effect of resonant air-coupled emission results in airborne waves emanating from the defect area, which can be received by a commercial microphone (low LDR frequency) or an air-coupled ultrasonic transducer (high frequency LDR). A series of experiments confirm the feasibility of both contact and non-contact versions of the technique for NDT and imaging of simulated and realistic defects (impacts, delaminations, and disbonds) in composites.

Low dose radiation adaptive protection to control neurodegenerative diseases.

PubMed

Doss, Mohan

2014-05-01

Concerns have been expressed recently regarding the observed increased DNA damage from activities such as thinking and exercise. Such concerns have arisen from an incomplete accounting of the full effects of the increased oxidative damage. When the effects of the induced adaptive protective responses such as increased antioxidants and DNA repair enzymes are taken into consideration, there would be less endogenous DNA damage during the subsequent period of enhanced defenses, resulting in improved health from the thinking and exercise activities. Low dose radiation (LDR), which causes oxidative stress and increased DNA damage, upregulates adaptive protection systems that may decrease diseases in an analogous manner. Though there are ongoing debates regarding LDR's carcinogenicity, with two recent advisory committee reports coming to opposite conclusions, data published since the time of the reports have overwhelmingly ruled out its carcinogenicity, paving the way for consideration of its potential use for disease reduction. LDR adaptive protection is a promising approach to control neurodegenerative diseases, for which there are no methods of prevention or cure. Preparation of a compelling ethics case would pave the way for LDR clinical studies and progress in dealing with neurodegenerative diseases.

Combination therapeutics of Nilotinib and radiation in acute lymphoblastic leukemia as an effective method against drug-resistance.

PubMed

Kaveh, Kamran; Takahashi, Yutaka; Farrar, Michael A; Storme, Guy; Guido, Marcucci; Piepenburg, Jamie; Penning, Jackson; Foo, Jasmine; Leder, Kevin Z; Hui, Susanta K

2017-07-01

Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) is characterized by a very poor prognosis and a high likelihood of acquired chemo-resistance. Although tyrosine kinase inhibitor (TKI) therapy has improved clinical outcome, most ALL patients relapse following treatment with TKI due to the development of resistance. We developed an in vitro model of Nilotinib-resistant Ph+ leukemia cells to investigate whether low dose radiation (LDR) in combination with TKI therapy overcome chemo-resistance. Additionally, we developed a mathematical model, parameterized by cell viability experiments under Nilotinib treatment and LDR, to explain the cellular response to combination therapy. The addition of LDR significantly reduced drug resistance both in vitro and in computational model. Decreased expression level of phosphorylated AKT suggests that the combination treatment plays an important role in overcoming resistance through the AKT pathway. Model-predicted cellular responses to the combined therapy provide good agreement with experimental results. Augmentation of LDR and Nilotinib therapy seems to be beneficial to control Ph+ leukemia resistance and the quantitative model can determine optimal dosing schedule to enhance the effectiveness of the combination therapy.

Different responses of tumor and normal cells to low-dose radiation

PubMed Central

Liu, Ning; Wang, Hao; Shang, Qingjun; Jiang, Peng; Zhang, Yuanmei

2013-01-01

Aim of the study We demonstrated stimulation of both erythrocyte immune function and superoxide dismutase activity in tumor-bearing mice in response to whole-body 75 mGy X-rays. In addition, we enhanced the chemotherapeutic effect by exposing tumor-bearing mice to low-dose radiation (LDR). This study aims to investigate the different responses of tumor cells and normal cells to LDR. Material and methods Survival fraction, micronucleus frequency, and cell cycle of Lewis cells and primary human fibroblast AG01522 cells were measured. S180 sarcoma cells were implanted in mice, and tumor sizes were measured in vivo. Results In response to LDR exposure in vitro, a stimulating effect was observed in AG01522 cells but not in Lewis cells. Low-dose radiation did not cause an adaptive response in the Lewis cell cycle. Lack of an LDR-induced radioadaptive response in tumor cells was observed in tumor-bearing mouse models. Furthermore, a higher apoptotic effect and lower expression of the anti-apoptosis gene Bcl-2 were found in tumor cells of tumor-bearing mice exposed to D1 + D2 than those in tumor cells of tumor-bearing mice exposed to D2 alone. Conclusions Different responses of tumor cells and normal cells to LDR were found. Low-dose radiation was found to stimulate the growth of normal cells but not of tumor cells in vitro and in vivo, which is a very important and clinically relevant phenomenon. PMID:24592123

Radiobiological equivalent of low/high dose rate brachytherapy and evaluation of tumor and normal responses to the dose.

PubMed

Manimaran, S

2007-06-01

The aim of this study was to compare the biological equivalent of low-dose-rate (LDR) and high-dose-rate (HDR) brachytherapy in terms of the more recent linear quadratic (LQ) model, which leads to theoretical estimation of biological equivalence. One of the key features of the LQ model is that it allows a more systematic radiobiological comparison between different types of treatment because the main parameters alpha/beta and micro are tissue-specific. Such comparisons also allow assessment of the likely change in the therapeutic ratio when switching between LDR and HDR treatments. The main application of LQ methodology, which focuses on by increasing the availability of remote afterloading units, has been to design fractionated HDR treatments that can replace existing LDR techniques. In this study, with LDR treatments (39 Gy in 48 h) equivalent to 11 fractions of HDR irradiation at the experimental level, there are increasing reports of reproducible animal models that may be used to investigate the biological basis of brachytherapy and to help confirm theoretical predictions. This is a timely development owing to the nonavailability of sufficient retrospective patient data analysis. It appears that HDR brachytherapy is likely to be a viable alternative to LDR only if it is delivered without a prohibitively large number of fractions (e.g., fewer than 11). With increased scientific understanding and technological capability, the prospect of a dose equivalent to HDR brachytherapy will allow greater utilization of the concepts discussed in this article.

Comparison of the rolling circle amplification and ligase-dependent reaction methods for the identification of opportunistic Exophiala species.

PubMed

Kaplan, Engin; Ilkit, Macit; de Hoog, G Sybren

2017-10-26

We developed two ligase-dependent probe amplification assays based on rolling circle amplification (RCA) and the ligase-dependent reaction (LDR) to differentiate species of Exophiala targeting the rDNA internal transcribed spacer region. We focused on Exophiala dermatitidis and E. phaeomuriformis, two opportunistic inhabitants of indoor wet cells, and further detected E. heteromorpha, E. xenobiotica, and E. crusticola; 57 reference isolates representing the five species were tested. Depending on the RCA probes used, the sensitivity was 100%, and the specificity ranged from 3.7% to 88.6% (median: 46.1%). In contrast, the sensitivity and specificity of the LDR probes targeting the same isolates were 88.6-100% (median: 95.8%) and 95.4-100% (median: 97.7%), respectively. We analyzed 198 additional environmental isolates representing the same Exophiala species. Overall, the sensitivity and specificity of LDR ranged from 89.7% to 100% (median: 94.1%) and from 93.9% to 100% (median: 96.9%), respectively. The assessment of performance and validation of LDR probes using SYBR Green quantitative polymerase chain reaction revealed high reproducibility and an acceptable range limit, in line with the guidelines of the European Network of GMO Laboratories. In conclusion, the LDR assay was more reliable and less expensive than RCA for species-level identification of Exophiala isolates. © The Author 2017. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Low dose rate brachytherapy (LDR-BT) as monotherapy for early stage prostate cancer in Italy: practice and outcome analysis in a series of 2237 patients from 11 institutions

PubMed Central

Fellin, Giovanni; Mirri, Maria A; Santoro, Luigi; Divan, Claudio; Mussari, Salvatore; Ziglio, Francesco; La Face, Beniamino; Barbera, Fernando; Buglione, Michela; Bandera, Laura; Ghedi, Barbara; Di Muzio, Nadia G; Losa, Andrea; Mangili, Paola; Nava, Luciano; Chiarlone, Renato; Ciscognetti, Nunzia; Gastaldi, Emilio; Cattani, Federica; Spoto, Ruggero; Vavassori, Andrea; Giglioli, Francesca R; Guarneri, Alessia; Cerboneschi, Valentina; Mignogna, Marcello; Paoluzzi, Mauro; Ravaglia, Valentina; Chiumento, Costanza; Clemente, Stefania; Fusco, Vincenzo; Santini, Roberto; Stefanacci, Marco; Mangiacotti, Francesco P; Martini, Marco; Palloni, Tiziana; Schinaia, Giuseppe; Lazzari, Grazia; Silvano, Giovanni; Magrini, Stefano; Ricardi, Umberto; Santoni, Riccardo; Orecchia, Roberto

2016-01-01

Objective: Low-dose-rate brachytherapy (LDR-BT) in localized prostate cancer is available since 15 years in Italy. We realized the first national multicentre and multidisciplinary data collection to evaluate LDR-BT practice, given as monotherapy, and outcome in terms of biochemical failure. Methods: Between May 1998 and December 2011, 2237 patients with early-stage prostate cancer from 11 Italian community and academic hospitals were treated with iodine-125 (125I) or palladium-103 LDR-BT as monotherapy and followed up for at least 2 years. 125I seeds were implanted in 97.7% of the patients: the mean dose received by 90% of target volume was 145 Gy; the mean target volume receiving 100% of prescribed dose (V100) was 91.1%. Biochemical failure-free survival (BFFS), disease-specific survival (DSS) and overall survival (OS) were estimated using Kaplan–Meier method. Log-rank test and multivariable Cox regression were used to evaluate the relationship of covariates with outcomes. Results: Median follow-up time was 65 months. 5- and 7-year DSS, OS and BFFS were 99 and 98%, 94 and 89%, and 92 and 88%, respectively. At multivariate analysis, the National Comprehensive Cancer Network score (p < 0.0001) and V100 (p = 0.09) were correlated with BFFS, with V100 effect significantly different between patients at low risk and those at intermediate/high risk (p = 0.04). Short follow-up and lack of toxicity data represent the main limitations for a global evaluation of LDR-BT. Conclusion: This first multicentre Italian report confirms LDR-BT as an excellent curative modality for low-/intermediate-risk prostate cancer. Advances in knowledge: Multidisciplinary teams may help to select adequately patients to be treated with brachytherapy, with a direct impact on the implant quality and, possibly, on outcome. PMID:27384381

Low dose rate brachytherapy (LDR-BT) as monotherapy for early stage prostate cancer in Italy: practice and outcome analysis in a series of 2237 patients from 11 institutions.

PubMed

Fellin, Giovanni; Mirri, Maria A; Santoro, Luigi; Jereczek-Fossa, Barbara A; Divan, Claudio; Mussari, Salvatore; Ziglio, Francesco; La Face, Beniamino; Barbera, Fernando; Buglione, Michela; Bandera, Laura; Ghedi, Barbara; Di Muzio, Nadia G; Losa, Andrea; Mangili, Paola; Nava, Luciano; Chiarlone, Renato; Ciscognetti, Nunzia; Gastaldi, Emilio; Cattani, Federica; Spoto, Ruggero; Vavassori, Andrea; Giglioli, Francesca R; Guarneri, Alessia; Cerboneschi, Valentina; Mignogna, Marcello; Paoluzzi, Mauro; Ravaglia, Valentina; Chiumento, Costanza; Clemente, Stefania; Fusco, Vincenzo; Santini, Roberto; Stefanacci, Marco; Mangiacotti, Francesco P; Martini, Marco; Palloni, Tiziana; Schinaia, Giuseppe; Lazzari, Grazia; Silvano, Giovanni; Magrini, Stefano; Ricardi, Umberto; Santoni, Riccardo; Orecchia, Roberto

2016-09-01

Low-dose-rate brachytherapy (LDR-BT) in localized prostate cancer is available since 15 years in Italy. We realized the first national multicentre and multidisciplinary data collection to evaluate LDR-BT practice, given as monotherapy, and outcome in terms of biochemical failure. Between May 1998 and December 2011, 2237 patients with early-stage prostate cancer from 11 Italian community and academic hospitals were treated with iodine-125 ((125)I) or palladium-103 LDR-BT as monotherapy and followed up for at least 2 years. (125)I seeds were implanted in 97.7% of the patients: the mean dose received by 90% of target volume was 145 Gy; the mean target volume receiving 100% of prescribed dose (V100) was 91.1%. Biochemical failure-free survival (BFFS), disease-specific survival (DSS) and overall survival (OS) were estimated using Kaplan-Meier method. Log-rank test and multivariable Cox regression were used to evaluate the relationship of covariates with outcomes. Median follow-up time was 65 months. 5- and 7-year DSS, OS and BFFS were 99 and 98%, 94 and 89%, and 92 and 88%, respectively. At multivariate analysis, the National Comprehensive Cancer Network score (p < 0.0001) and V100 (p = 0.09) were correlated with BFFS, with V100 effect significantly different between patients at low risk and those at intermediate/high risk (p = 0.04). Short follow-up and lack of toxicity data represent the main limitations for a global evaluation of LDR-BT. This first multicentre Italian report confirms LDR-BT as an excellent curative modality for low-/intermediate-risk prostate cancer. Multidisciplinary teams may help to select adequately patients to be treated with brachytherapy, with a direct impact on the implant quality and, possibly, on outcome.

Low-dose-rate brachytherapy for the treatment of localised prostate cancer in men with a high risk of disease relapse.

PubMed

Laing, Robert; Uribe, Jennifer; Uribe-Lewis, Santiago; Money-Kyrle, Julian; Perna, Carla; Chintzoglou, Stylianos; Khaksar, Sara; Langley, Stephen E M

2018-04-01

To report clinical outcomes of 125 I low-dose-rate prostate brachytherapy (LDR-PB) as monotherapy or combined with androgen-deprivation therapy (ADT) and/or external beam radiotherapy (EBRT) in high-risk localised prostate cancer. Analysis of clinical outcomes from a prospective cohort of patients treated with LDR-PB alone or combined treatment in a single institution. Men with a high risk of disease relapse were identified by the National Institute for Health and Care Excellence (NICE) criteria or by the National Comprehensive Cancer Network (NCCN) criteria. Relapse-free survival (RFS), overall survival (OS), prostate cancer-specific survival (PCSS), and metastases-free survival (MFS), were analysed together with patient-reported symptom scores and physician-reported adverse events. The NICE and NCCN criteria identified 267 and 202 high-risk patients, respectively. NICE-defined patients had significantly lower pre-treatment PSA levels, Gleason scores <7, and a greater proportion of patients who received LDR-PB monotherapy. At 9 years after implantation RFS was 89% and 87% in the NICE and NCCN groups, respectively (log-rank P = 0.637), and OS 93% and 94%, respectively (log-rank P = 0.481). All of the survival estimates were similar between LDR-PB monotherapy and combined therapies. Cox proportional hazards regression confirmed RFS was similar between the treatment types. Treatment-related toxicity was also similar between the treatment methods. LDR-PB is effective at controlling localised prostate cancer in patients with a high risk of disease relapse. As the present study was not randomised, it is not possible to define those patients who need the addition of ADT and/or EBRT. However, the NICE criteria appear suitable to define treatment options where patients could benefit from LDR-PB as monotherapy or combined treatment. This choice should be discussed with the patient taking into account comorbidities and presence of multiple high-risk factors. © 2018 The Authors BJU International © 2018 BJU International Published by John Wiley & Sons Ltd.

Genotoxic effects of high dose rate X-ray and low dose rate gamma radiation in ApcMin/+ mice.

PubMed

Graupner, Anne; Eide, Dag M; Brede, Dag A; Ellender, Michele; Lindbo Hansen, Elisabeth; Oughton, Deborah H; Bouffler, Simon D; Brunborg, Gunnar; Olsen, Ann Karin

2017-10-01

Risk estimates for radiation-induced cancer in humans are based on epidemiological data largely drawn from the Japanese atomic bomb survivor studies, which received an acute high dose rate (HDR) ionising radiation. Limited knowledge exists about the effects of chronic low dose rate (LDR) exposure, particularly with respect to the application of the dose and dose rate effectiveness factor. As part of a study to investigate the development of colon cancer following chronic LDR vs. acute HDR radiation, this study presents the results of genotoxic effects in blood of exposed mice. CBAB6 F1 Apc +/+ (wild type) and Apc Min/+ mice were chronically exposed to estimated whole body absorbed doses of 1.7 or 3.2 Gy 60 Co-γ-rays at a LDR (2.2 mGy h -1 ) or acutely exposed to 2.6 Gy HDR X-rays (1.3 Gy min -1 ). Genotoxic endpoints assessed in blood included chromosomal damage (flow cytometry based micronuclei (MN) assay), mutation analyses (Pig-a gene mutation assay), and levels of DNA lesions (Comet assay, single-strand breaks (ssb), alkali labile sites (als), oxidized DNA bases). Ionising radiation (ca. 3 Gy) induced genotoxic effects dependent on the dose rate. Chromosomal aberrations (MN assay) increased 3- and 10-fold after chronic LDR and acute HDR, respectively. Phenotypic mutation frequencies as well as DNA lesions (ssb/als) were modulated after acute HDR but not after chronic LDR. The Apc Min/+ genotype did not influence the outcome in any of the investigated endpoints. The results herein will add to the scant data available on genotoxic effects following chronic LDR of ionising radiation. Environ. Mol. Mutagen. 58:560-569, 2017. © 2017 The Authors Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society. © 2017 The Authors Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society.

Genotoxic effects of high dose rate X‐ray and low dose rate gamma radiation in ApcMin/+ mice

PubMed Central

Eide, Dag M.; Brede, Dag A.; Ellender, Michele; Lindbo Hansen, Elisabeth; Oughton, Deborah H.; Bouffler, Simon D.; Brunborg, Gunnar; Olsen, Ann Karin

2017-01-01

Risk estimates for radiation‐induced cancer in humans are based on epidemiological data largely drawn from the Japanese atomic bomb survivor studies, which received an acute high dose rate (HDR) ionising radiation. Limited knowledge exists about the effects of chronic low dose rate (LDR) exposure, particularly with respect to the application of the dose and dose rate effectiveness factor. As part of a study to investigate the development of colon cancer following chronic LDR vs. acute HDR radiation, this study presents the results of genotoxic effects in blood of exposed mice. CBAB6 F1 Apc+/+ (wild type) and ApcMin/+ mice were chronically exposed to estimated whole body absorbed doses of 1.7 or 3.2 Gy 60Co‐γ‐rays at a LDR (2.2 mGy h−1) or acutely exposed to 2.6 Gy HDR X‐rays (1.3 Gy min−1). Genotoxic endpoints assessed in blood included chromosomal damage (flow cytometry based micronuclei (MN) assay), mutation analyses (Pig‐a gene mutation assay), and levels of DNA lesions (Comet assay, single‐strand breaks (ssb), alkali labile sites (als), oxidized DNA bases). Ionising radiation (ca. 3 Gy) induced genotoxic effects dependent on the dose rate. Chromosomal aberrations (MN assay) increased 3‐ and 10‐fold after chronic LDR and acute HDR, respectively. Phenotypic mutation frequencies as well as DNA lesions (ssb/als) were modulated after acute HDR but not after chronic LDR. The ApcMin/+ genotype did not influence the outcome in any of the investigated endpoints. The results herein will add to the scant data available on genotoxic effects following chronic LDR of ionising radiation. Environ. Mol. Mutagen. 58:560–569, 2017. © 2017 The Authors Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society PMID:28856770

ASCENDE-RT: An Analysis of Treatment-Related Morbidity for a Randomized Trial Comparing a Low-Dose-Rate Brachytherapy Boost with a Dose-Escalated External Beam Boost for High- and Intermediate-Risk Prostate Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rodda, Sree; Tyldesley, Scott; Department of Surgery, University of British Columbia, Vancouver, British Columbia

Purpose: To report the genitourinary (GU) and gastrointestinal (GI) morbidity and erectile dysfunction in a randomized trial comparing 2 methods of dose escalation for high- and intermediate-risk prostate cancer. Methods and Materials: ASCENDE-RT (Androgen Suppression Combined with Elective Nodal and Dose Escalated Radiation Therapy) enrolled 398 men, median age 68 years, who were then randomized to either a standard arm that included 12 months of androgen deprivation therapy and pelvic irradiation to 46 Gy followed by a dose-escalated external beam radiation therapy (DE-EBRT) boost to 78 Gy, or an experimental arm that substituted a low-dose-rate prostate brachytherapy (LDR-PB) boost. At clinic visits, investigators recorded GUmore » and GI morbidity and information on urinary continence, catheter use, and erectile function. Exclusion of 15 who received nonprotocol treatment and correction of 14 crossover events left 195 men who actually received a DE-EBRT boost and 188, an LDR-PB boost. Median follow-up was 6.5 years. Results: The LDR-PB boost increased the risk of needing temporary catheterization and/or requiring incontinence pads. At 5 years the cumulative incidence of grade 3 GU events was 18.4% for LDR-PB, versus 5.2% for DE-EBRT (P<.001). Compared with the cumulative incidence, the 5-year prevalence of grade 3 GU morbidity was substantially lower for both arms (8.6% vs 2.2%, P=.058). The 5-year cumulative incidence of grade 3 GI events was 8.1% for LDR-PB, versus 3.2% for DE-EBRT (P=.124). The 5-year prevalence of grade 3 GI toxicity was lower than the cumulative incidence for both arms (1.0% vs 2.2%, respectively). Among men reporting adequate baseline erections, 45% of LDR-PB patients reported similar erectile function at 5 years, versus 37% after DE-EBRT (P=.30). Conclusions: The incidence of acute and late GU morbidity was higher after LDR-PB boost, and there was a nonsignificant trend for worse GI morbidity. No differences in the frequency of erectile dysfunction were observed.« less

Risk of solid cancer in low dose-rate radiation epidemiological studies and the dose-rate effectiveness factor.

PubMed

Shore, Roy; Walsh, Linda; Azizova, Tamara; Rühm, Werner

2017-10-01

Estimated radiation risks used for radiation protection purposes have been based primarily on the Life Span Study (LSS) of atomic bomb survivors who received brief exposures at high dose rates, many with high doses. Information is needed regarding radiation risks from low dose-rate (LDR) exposures to low linear-energy-transfer (low-LET) radiation. We conducted a meta-analysis of LDR epidemiologic studies that provide dose-response estimates of total solid cancer risk in adulthood in comparison to corresponding LSS risks, in order to estimate a dose rate effectiveness factor (DREF). We identified 22 LDR studies with dose-response risk estimates for solid cancer after minimizing information overlap. For each study, a parallel risk estimate was derived from the LSS risk model using matching values for sex, mean ages at first exposure and attained age, targeted cancer types, and accounting for type of dosimetric assessment. For each LDR study, a ratio of the excess relative risk per Gy (ERR Gy -1 ) to the matching LSS ERR risk estimate (LDR/LSS) was calculated, and a meta-analysis of the risk ratios was conducted. The reciprocal of the resultant risk ratio provided an estimate of the DREF. The meta-analysis showed a LDR/LSS risk ratio of 0.36 (95% confidence interval [CI] 0.14, 0.57) for the 19 studies of solid cancer mortality and 0.33 (95% CI 0.13, 0.54) when three cohorts with only incidence data also were added, implying a DREF with values around 3, but statistically compatible with 2. However, the analyses were highly dominated by the Mayak worker study. When the Mayak study was excluded the LDR/LSS risk ratios increased: 1.12 (95% CI 0.40, 1.84) for mortality and 0.54 (95% CI 0.09, 0.99) for mortality + incidence, implying a lower DREF in the range of 1-2. Meta-analyses that included only cohorts in which the mean dose was <100 mGy yielded a risk ratio of 1.06 (95% CI 0.30, 1.83) for solid cancer mortality and 0.58 (95% CI 0.10, 1.06) for mortality + incidence data. The interpretation of a best estimate for a value of the DREF depends on the appropriateness of including the Mayak study. This study indicates a range of uncertainty in the value of DREF between 1 and about 2 after protracted radiation exposure. The LDR data provide direct evidence regarding risk from exposures at low dose rates as an important complement to the LSS risk estimates used for radiation protection purposes.

A multiplex PCR/LDR assay for simultaneous detection and identification of the NIAID category B bacterial food and water-borne pathogens.

PubMed

Rundell, Mark S; Pingle, Maneesh; Das, Sanchita; Hussain, Aashiq; Ocheretina, Oksana; Charles, Macarthur; Larone, Davise H; Spitzer, Eric D; Golightly, Linnie; Barany, Francis

2014-06-01

Enteric pathogens that cause gastroenteritis remain a major global health concern. The goal of this study was to develop a multiplex PCR/ligation detection reaction (LDR) assay for the detection of all NIAID category B bacterial food and water-borne pathogens directly from stool specimens. To validate the PCR/LDR assay, clinical isolates of Campylobacter spp., Vibrio spp., Shigella spp., Salmonella spp., Listeria monocytogenes, Yersinia enterocolitica, and diarrheagenic Escherichia coli were tested. The sensitivity and specificity of the assay were assessed using a large number of seeded culture-negative stool specimens and a smaller set of clinical specimens from Haiti. The overall sensitivity ranged from 91% to 100% (median 100%) depending on the species. For the majority of organisms, the sensitivity was 100%. The overall specificity based on initial testing ranged from 98% to 100% depending on the species. After additional testing of discordant samples, the lowest specificity was 99.4%. PCR/LDR detected additional category B agents (particularly diarrheagenic E. coli) in 11/40 specimens from Haiti that were culture-positive for V. cholerae and in approximately 1% of routine culture-negative stool specimens from a hospital in New York. This study demonstrated the ability of the PCR/LDR assay to detect a large comprehensive panel of category B enteric bacterial pathogens as well as mixed infections. This type of assay has the potential to provide earlier warnings of possible public health threats and more accurate surveillance of food and water-borne pathogens. Copyright © 2014 Elsevier Inc. All rights reserved.

The use of nomograms in LDR-HDR prostate brachytherapy.

PubMed

Pujades, Ma Carmen; Camacho, Cristina; Perez-Calatayud, Jose; Richart, José; Gimeno, Jose; Lliso, Françoise; Carmona, Vicente; Ballester, Facundo; Crispín, Vicente; Rodríguez, Silvia; Tormo, Alejandro

2011-09-01

The common use of nomograms in Low Dose Rate (LDR) permanent prostate brachytherapy (BT) allows to estimate the number of seeds required for an implant. Independent dosimetry verification is recommended for each clinical dosimetry in BT. Also, nomograms can be useful for dose calculation quality assurance and they could be adapted to High Dose Rate (HDR). This work sets nomograms for LDR and HDR prostate-BT implants, which are applied to three different institutions that use different implant techniques. Patients treated throughout 2010 till April 2011 were considered for this study. This example was chosen to be the representative of the latest implant techniques and to ensure consistency in the planning. A sufficient number of cases for both BT modalities, prescription dose and different work methodology (depending on the institution) were taken into account. The specific nomograms were built using the correlation between the prostate volume and some characteristic parameters of each BT modality, such as the source Air Kerma Strength, number of implanted seeds in LDR or total radiation time in HDR. For each institution and BT modality, nomograms normalized to the prescribed dose were obtained and fitted to a linear function. The parameters of the adjustment show a good agreement between data and the fitting. It should be noted that for each institution these linear function parameters are different, indicating that each centre should construct its own nomograms. Nomograms for LDR and HDR prostate brachytherapy are simple quality assurance tools, specific for each institution. Nevertheless, their use should be complementary to the necessary independent verification.

A Multiplex PCR/LDR Assay for Simultaneous Detection and Identification of the NIAID Category B Bacterial Food and Water-borne Pathogens

PubMed Central

Rundell, Mark S.; Pingle, Maneesh; Das, Sanchita; Hussain, Aashiq; Ocheretina, Oksana; Charles, Macarthur; Larone, Davise H.; Spitzer, Eric D.; Golightly, Linnie; Barany, Francis

2014-01-01

Enteric pathogens that cause gastroenteritis remain a major global health concern. The goal of this study was to develop a multiplex PCR/LDR assay for the detection of all NIAID category B bacterial food and water-borne pathogens directly from stool specimens. To validate the PCR/LDR assay, clinical isolates of Campylobacter spp., Vibrio spp., Shigella spp., Salmonella spp., Listeria monocytogenes, Yersinia enterocolitica, and diarrheagenic Escherichia coli were tested. The sensitivity and specificity of the assay was assessed using a large number of seeded culture-negative stool specimens and a smaller set of clinical specimens from Haiti. The overall sensitivity ranged from 91 to 100% (median 100%) depending on the species. For the majority of organisms the sensitivity was 100%. The overall specificity based on initial testing ranged from 98% to 100% depending on the species. After additional testing of discordant samples the lowest specificity was 99.4%. PCR/LDR detected additional category B agents (particularly diarrheagenic E. coli) in 11/40 specimens from Haiti that were culture-positive for V. cholerae and in approximately 1% of routine culture-negative stool specimens from a hospital in New York. This study demonstrated the ability of the PCR/LDR assay to detect a large comprehensive panel of category B enteric bacterial pathogens as well as mixed infections. This type of assay has the potential to provide earlier warnings of possible public health threats and more accurate surveillance of food and water-borne pathogens. PMID:24709368

The use of nomograms in LDR-HDR prostate brachytherapy

PubMed Central

Camacho, Cristina; Perez-Calatayud, Jose; Richart, José; Gimeno, Jose; Lliso, Françoise; Carmona, Vicente; Ballester, Facundo; Crispín, Vicente; Rodríguez, Silvia; Tormo, Alejandro

2011-01-01

Purpose The common use of nomograms in Low Dose Rate (LDR) permanent prostate brachytherapy (BT) allows to estimate the number of seeds required for an implant. Independent dosimetry verification is recommended for each clinical dosimetry in BT. Also, nomograms can be useful for dose calculation quality assurance and they could be adapted to High Dose Rate (HDR). This work sets nomograms for LDR and HDR prostate-BT implants, which are applied to three different institutions that use different implant techniques. Material and methods Patients treated throughout 2010 till April 2011 were considered for this study. This example was chosen to be the representative of the latest implant techniques and to ensure consistency in the planning. A sufficient number of cases for both BT modalities, prescription dose and different work methodology (depending on the institution) were taken into account. The specific nomograms were built using the correlation between the prostate volume and some characteristic parameters of each BT modality, such as the source Air Kerma Strength, number of implanted seeds in LDR or total radiation time in HDR. Results For each institution and BT modality, nomograms normalized to the prescribed dose were obtained and fitted to a linear function. The parameters of the adjustment show a good agreement between data and the fitting. It should be noted that for each institution these linear function parameters are different, indicating that each centre should construct its own nomograms. Conclusions Nomograms for LDR and HDR prostate brachytherapy are simple quality assurance tools, specific for each institution. Nevertheless, their use should be complementary to the necessary independent verification. PMID:23346120

Health Literacy of Living Kidney Donors and Kidney Transplant Recipients

PubMed Central

Dageforde, Leigh Anne; Petersen, Alec W.; Feurer, Irene D.; Cavanaugh, Kerri L.; Harms, Kelly A.; Ehrenfeld, Jesse M.; Moore, Derek E.

2015-01-01

Background Health literacy (HL) may be a mediator for known socioeconomic and racial disparities in living kidney donation. Methods We evaluated the associations of patient and demographic characteristics with HL in living kidney donors (LD), living donor kidney transplant recipients (LDR), and deceased donor recipients (DDR) in a single center retrospective review of patients undergoing kidney donation or transplantation from September 2010 to July 2012. HL and demographic data were collected. HL was assessed via the Short Literacy Survey (SLS) comprising three self-reported screening questions scored using the 5-point Likert scale [low (3-8), moderate (9-14), high (15)]. Chi-square and logistic regression were used to test factors associated with lower HL. Results The sample included 360 adults (105 LD, 103 LDR, 152 DDR; 46±14 years; 70% white; 56% male; 14±3 years of education). HL scores were skewed (49% high, 41% moderate, 10% low). The distribution of HL categories differed significantly among groups (p=0.019). After controlling for age, race, gender, education and a race-education interaction term, DDR were more likely to have moderate or low HL than LDR (OR 1.911; 95%CI 1.096, 3.332; p=0.022) Conclusions Overall, living donors had high HL. The distribution of low, moderate and high HL differed significantly between LD, DDR and LDR. DDR had a higher likelihood of having low HL than LDR. Screening kidney transplant candidates and donors for lower HL may identify barriers to living donation. Future interventions addressing HL may be important to increase living donation and reduce disparities. PMID:24573114

Impact of point A asymmetry on local control and survival for low dose-rate (LDR) brachytherapy in cervical cancer.

PubMed

Opfermann, Krisha J; Wahlquist, Amy; Watkins, John; Kohler, Matthew; Jenrette, Joseph

2012-03-01

To evaluate whether Point A asymmetry in low dose-rate (LDR) brachytherapy is associated with local control (LC), disease-free survival (DFS) and/or overall survival (OS). A retrospective analysis of disease control and survival outcomes was conducted for patients who underwent LDR brachytherapy for advanced cervical cancer. Institutional protocol entailed concurrent chemotherapy and whole pelvis radiotherapy (WPRT) over 5 weeks, followed by placement of Fletcher-Suit tandem and colpostat applicators at weeks 6 and 8. Objective Point A doses, 80-85 Gy, were accomplished by placement of Cesium-137 (Cs-137) sources. Cox proportional hazards regression models were used to assess associations between disease control and survival endpoints with variables of interest. The records of 50 patients with FIGO stage IB1-IVA cervical cancer undergoing LDR brachytherapy at our institution were identified. Thirty of these patients had asymmetry > 2.5%, and 11 patients had asymmetry > 5%. At a median survivor follow-up of 20.25 months, 15 patients had experienced disease failure (including 5 cervical/vaginal apex only failures and 2 failures encompassing the local site). Right/left dose asymmetry at Point A was associated with statistically significantly inferior LC (p = 0.035) and inferior DFS (p = 0.011) for patients with mean Point A dose of > 80 Gy. Insufficient evidence existed to conclude an association with OS. LDR brachytherapy may be associated with clinically significant dose asymmetry. The present study demonstrates that patients with Point A asymmetry have a higher risk of failure for DFS and LC.

Impact of point A asymmetry on local control and survival for low dose-rate (LDR) brachytherapy in cervical cancer

PubMed Central

Wahlquist, Amy; Watkins, John; Kohler, Matthew; Jenrette, Joseph

2012-01-01

Purpose To evaluate whether Point A asymmetry in low dose-rate (LDR) brachytherapy is associated with local control (LC), disease-free survival (DFS) and/or overall survival (OS). Material and methods A retrospective analysis of disease control and survival outcomes was conducted for patients who underwent LDR brachytherapy for advanced cervical cancer. Institutional protocol entailed concurrent chemotherapy and whole pelvis radiotherapy (WPRT) over 5 weeks, followed by placement of Fletcher-Suit tandem and colpostat applicators at weeks 6 and 8. Objective Point A doses, 80-85 Gy, were accomplished by placement of Cesium-137 (Cs-137) sources. Cox proportional hazards regression models were used to assess associations between disease control and survival endpoints with variables of interest. Results The records of 50 patients with FIGO stage IB1-IVA cervical cancer undergoing LDR brachytherapy at our institution were identified. Thirty of these patients had asymmetry > 2.5%, and 11 patients had asymmetry > 5%. At a median survivor follow-up of 20.25 months, 15 patients had experienced disease failure (including 5 cervical/vaginal apex only failures and 2 failures encompassing the local site). Right/left dose asymmetry at Point A was associated with statistically significantly inferior LC (p = 0.035) and inferior DFS (p = 0.011) for patients with mean Point A dose of > 80 Gy. Insufficient evidence existed to conclude an association with OS. Conclusions LDR brachytherapy may be associated with clinically significant dose asymmetry. The present study demonstrates that patients with Point A asymmetry have a higher risk of failure for DFS and LC. PMID:23346133

Antioxidant and antiapoptotic effects of sea cucumber and valsartan against doxorubicin-induced cardiotoxicity in rats: The role of low dose gamma irradiation.

PubMed

Ibrahim, Doaa M; Radwan, Rasha R; Abdel Fattah, Salma M

2017-05-01

Doxorubicin (DOX) is a highly effective antineoplastic drug; however, the clinical use of DOX is limited by its dose dependent cardiotoxicity. This study was conducted to evaluate the cardioprotective effect of sea cucumber and valsartan against DOX-induced cardiotoxicity in rats. Also, the role of exposure to low dose γ radiation (LDR) on each of them was investigated, since LDR could suppress various reactive oxygen species-related diseases. Rats received DOX (2.5mg/kg, ip) in six equal injections over a period of 2weeks, sea cucumber (14.4mg/kg, p.o) and valsartan (30mg/kg, p.o) for 8 successive weeks. Exposure to LDR (0.5Gy) was performed one day prior to DOX. Results revealed that DOX administration elevated serum levels of aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatine kinase (CK-MB) and troponin-I as well as increased cardiac lipid peroxide content and myeloperoxidase (MPO) activity. Additionally, it increased cardiac expressions of iNOS and caspase-3, accompanied by reduction in cardiac total protein and glutathione (GSH) contents. Treatment with sea cucumber or valsartan improved the cardiotoxicity of DOX. Their adjuvant therapy with LDR offers an additional benefit to the cardioprotection of the therapeutic drugs. These results confirmed by histopathological examination. In conclusion, sea cucumber and valsartan alone or combined with LDR attenuated DOX-induced cardiotoxicity via their antioxidant and anti-apoptotic activities and thus might be useful in the treatment of human patients under doxorubicin chemotherapy. Copyright © 2017 Elsevier B.V. All rights reserved.

Quality assurance of HDR prostate plans: program implementation at a community hospital.

PubMed

Rush, Jennifer B; Thomas, Michael D

2005-01-01

Adenocarcinoma of the prostate is currently the most commonly diagnosed cancer in men in the United States, and the second leading cause of cancer mortality. The utilization of radiation therapy is regarded as the definitive local therapy of choice for intermediate- and high-risk disease, in which there is increased risk for extracapsular extension, seminal vesicle invasion, or regional node involvement. High-dose-rate (HDR) brachytherapy is a logical treatment modality to deliver the boost dose to an external beam radiation therapy (EBRT) treatment to increase local control rates. From a treatment perspective, the utilization of a complicated treatment delivery system, the compressed time frame in which the procedure is performed, and the small number of large dose fractions make the implementation of a comprehensive quality assurance (QA) program imperative. One aspect of this program is the QA of the HDR treatment plan. Review of regulatory and medical physics professional publications shows that substantial general guidance is available. We provide some insight to the implementation of an HDR prostate plan program at a community hospital. One aspect addressed is the utilization of the low-dose-rate (LDR) planning system and the use of existing ultrasound image sets to familiarize the radiation therapy team with respect to acceptable HDR implant geometries. Additionally, the use of the LDR treatment planning system provided a means to prospectively determine the relationship between the treated isodose volume and the product of activity and time for the department's planning protocol prior to the first HDR implant. For the first 12 HDR prostate implants, the root-mean-square (RMS) deviation was 3.05% between the predicted product of activity and time vs. the actual plan values. Retrospective re-evaluation of the actual implant data reduced the RMS deviation to 2.36%.

Rectourethral fistula following LDR brachytherapy.

PubMed

Borchers, Holger; Pinkawa, Michael; Donner, Andreas; Wolter, Timm P; Pallua, Norbert; Eble, Michael J; Jakse, Gerhard

2009-01-01

Modern LDR brachytherapy has drastically reduced rectal toxicity and decreased the occurrence of rectourethral fistulas to <0.5% of patients. Therefore, symptoms of late-onset sequelae are often ignored initially. These fistulas cause severe patient morbidity and require interdisciplinary treatment. We report on the occurrence and management of a rectourethral fistula which occurred 4 years after (125)I seed implantation. Copyright 2009 S. Karger AG, Basel.

Technology Insight: Combined external-beam radiation therapy and brachytherapy in the management of prostate cancer.

PubMed

Hurwitz, Mark D

2008-11-01

External-beam radiation therapy (EBRT) combined with brachytherapy is an attractive treatment option for selected patients with clinically localized prostate cancer. This therapeutic strategy offers dosimetric coverage if local-regional microscopic disease is present and provides a highly conformal boost of radiation to the prostate and immediate surrounding tissues. Either low-dose-rate (LDR) permanent brachytherapy or high-dose-rate (HDR) temporary brachytherapy can be combined with EBRT; such combined-modality therapy (CMT) is typically used to treat patients with intermediate-risk to high-risk, clinically localized disease. Controversy persists with regard to indications for CMT, choice of LDR or HDR boost, isotope selection for LDR, and integration of EBRT and brachytherapy. Initial findings from prospective, multicenter trials of CMT support the feasibility of this strategy. Updated results from these trials as well as those of ongoing and new phase III trials should help to define the role of CMT in the management of prostate cancer. In the meantime, long-term expectations for outcomes of CMT are based largely on the experience of single institutions, which demonstrate that CMT with EBRT and either LDR or HDR brachytherapy can provide freedom from disease recurrence with acceptable toxicity.

Effect of dose rate on residual γ-H2AX levels and frequency of micronuclei in X-irradiated mouse lymphocytes.

PubMed

Turner, H C; Shuryak, I; Taveras, M; Bertucci, A; Perrier, J R; Chen, C; Elliston, C D; Johnson, G W; Smilenov, L B; Amundson, S A; Brenner, D J

2015-03-01

The biological risks associated with low-dose-rate (LDR) radiation exposures are not yet well defined. To assess the risk related to DNA damage, we compared the yields of two established biodosimetry end points, γ-H2AX and micronuclei (MNi), in peripheral mouse blood lymphocytes after prolonged in vivo exposure to LDR X rays (0.31 cGy/min) vs. acute high-dose-rate (HDR) exposure (1.03 Gy/min). C57BL/6 mice were total-body irradiated with 320 kVP X rays with doses of 0, 1.1, 2.2 and 4.45 Gy. Residual levels of total γ-H2AX fluorescence in lymphocytes isolated 24 h after the start of irradiation were assessed using indirect immunofluorescence methods. The terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay was used to determine apoptotic cell frequency in lymphocytes sampled at 24 h. Curve fitting analysis suggested that the dose response for γ-H2AX yields after acute exposures could be described by a linear dependence. In contrast, a linear-quadratic dose-response shape was more appropriate for LDR exposure (perhaps reflecting differences in repair time after different LDR doses). Dose-rate sparing effects (P < 0.05) were observed at doses ≤2.2 Gy, such that the acute dose γ-H2AX and TUNEL-positive cell yields were significantly larger than the equivalent LDR yields. At the 4.45 Gy dose there was no difference in γ-H2AX expression between the two dose rates, whereas there was a two- to threefold increase in apoptosis in the LDR samples compared to the equivalent 4.45 Gy acute dose. Micronuclei yields were measured at 24 h and 7 days using the in vitro cytokinesis-blocked micronucleus (CBMN) assay. The results showed that MNi yields increased up to 2.2 Gy with no further increase at 4.45 Gy and with no detectable dose-rate effect across the dose range 24 h or 7 days post exposure. In conclusion, the γ-H2AX biomarker showed higher sensitivity to measure dose-rate effects after low-dose LDR X rays compared to MNi formation; however, confounding factors such as variable repair times post exposure, increased cell killing and cell cycle block likely contributed to the yields of MNi with accumulating doses of ionizing radiation.

Evaluation of a Machine-Learning Algorithm for Treatment Planning in Prostate Low-Dose-Rate Brachytherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nicolae, Alexandru; Department of Medical Physics, Odette Cancer Center, Sunnybrook Health Sciences Centre, Toronto, Ontario; Morton, Gerard

Purpose: This work presents the application of a machine learning (ML) algorithm to automatically generate high-quality, prostate low-dose-rate (LDR) brachytherapy treatment plans. The ML algorithm can mimic characteristics of preoperative treatment plans deemed clinically acceptable by brachytherapists. The planning efficiency, dosimetry, and quality (as assessed by experts) of preoperative plans generated with an ML planning approach was retrospectively evaluated in this study. Methods and Materials: Preimplantation and postimplantation treatment plans were extracted from 100 high-quality LDR treatments and stored within a training database. The ML training algorithm matches similar features from a new LDR case to those within the trainingmore » database to rapidly obtain an initial seed distribution; plans were then further fine-tuned using stochastic optimization. Preimplantation treatment plans generated by the ML algorithm were compared with brachytherapist (BT) treatment plans in terms of planning time (Wilcoxon rank sum, α = 0.05) and dosimetry (1-way analysis of variance, α = 0.05). Qualitative preimplantation plan quality was evaluated by expert LDR radiation oncologists using a Likert scale questionnaire. Results: The average planning time for the ML approach was 0.84 ± 0.57 minutes, compared with 17.88 ± 8.76 minutes for the expert planner (P=.020). Preimplantation plans were dosimetrically equivalent to the BT plans; the average prostate V150% was 4% lower for ML plans (P=.002), although the difference was not clinically significant. Respondents ranked the ML-generated plans as equivalent to expert BT treatment plans in terms of target coverage, normal tissue avoidance, implant confidence, and the need for plan modifications. Respondents had difficulty differentiating between plans generated by a human or those generated by the ML algorithm. Conclusions: Prostate LDR preimplantation treatment plans that have equivalent quality to plans created by brachytherapists can be rapidly generated using ML. The adoption of ML in the brachytherapy workflow is expected to improve LDR treatment plan uniformity while reducing planning time and resources.« less

Balloon-borne three-meter telescope for far-infrared and submillimeter astronomy

NASA Technical Reports Server (NTRS)

Fazio, Giovanni G.; Hoffmann, William F.; Harper, Doyal A.

1988-01-01

The scientific objectives, engineering analysis and design, results of technology development, and focal-plane instrumentation for a two-meter balloon-borne telescope for far-infrared and submillimeter astronomy are presented. The unique capabilities of balloon-borne observations are discussed. A program summary emphasizes the development of the two-meter design. The relationship of the Large Deployable Reflector (LDR) is also discussed. Detailed treatment is given to scientific objectives, gondola design, the mirror development program, experiment accommodations, ground support equipment requirements, NSBF design drivers and payload support requirements, the implementation phase summary development plan, and a comparison of three-meter and two-meter gondola concepts.

Concentrically trained cyclists are not more susceptible to eccentric exercise-induced muscle damage than are stretch-shortening exercise-trained runners.

PubMed

Snieckus, Audrius; Kamandulis, Sigitas; Venckūnas, Tomas; Brazaitis, Marius; Volungevičius, Gintautas; Skurvydas, Albertas

2013-03-01

Here, we test the hypothesis that continuous concentric exercise training renders skeletal muscles more susceptible to damage in response to eccentric exercise. Elite road cyclists (CYC; n = 10, training experience 8.1 ± 2.0 years, age 22.9 ± 3.7 years), long-distance runners (LDR; n = 10, 9.9 ± 2.3 years, 24.4 ± 2.5 years), and healthy untrained (UT) men (n = 10; 22.4 ± 1.7 years) performed 100 submaximal eccentric contractions at constant angular velocity of 60° s(-1). Concentric isokinetic peak torque, isometric maximal voluntary contraction (MVC), and electrically induced knee extension torque were measured at baseline and immediately and 48 h after an eccentric exercise bout. Muscle soreness was assessed and plasma creatine kinase (CK) activity was measured at baseline and 48 h after exercise. Voluntary and electrically stimulated knee extension torque reduction were significantly greater (p < 0.05) in UT than in LDR and CYC. Immediately and 48 h after exercise, MVC decreased by 32 % and 20 % in UT, 20 % and 5 % in LDR, and 25 % and 6 % in CYC. Electrically induced 20 Hz torque decreased at the same times by 61 and 29 % in UT, 40 and 17 % in LDR, and 26 and 14 % in CYC. Muscle soreness and plasma CK activity 48 h after exercise did not differ significantly between athletes and UT subjects. In conclusion, even though elite endurance athletes are more resistant to eccentric exercise-induced muscle damage than are UT people, stretch-shortening exercise-trained LDR have no advantage over concentrically trained CYC.

The Cancer of the Prostate Risk Assessment (CAPRA) score predicts biochemical recurrence in intermediate-risk prostate cancer treated with external beam radiotherapy (EBRT) dose escalation or low-dose rate (LDR) brachytherapy.

PubMed

Krishnan, Vimal; Delouya, Guila; Bahary, Jean-Paul; Larrivée, Sandra; Taussky, Daniel

2014-12-01

To study the prognostic value of the University of California, San Francisco Cancer of the Prostate Risk Assessment (CAPRA) score to predict biochemical failure (bF) after various doses of external beam radiotherapy (EBRT) and/or permanent seed low-dose rate (LDR) prostate brachytherapy (PB). We retrospectively analysed 345 patients with intermediate-risk prostate cancer, with PSA levels of 10-20 ng/mL and/or Gleason 7 including 244 EBRT patients (70.2-79.2 Gy) and 101 patients treated with LDR PB. The minimum follow-up was 3 years. No patient received primary androgen-deprivation therapy. bF was defined according to the Phoenix definition. Cox regression analysis was used to estimate the differences between CAPRA groups. The overall bF rate was 13% (45/345). The CAPRA score, as a continuous variable, was statistically significant in multivariate analysis for predicting bF (hazard ratio [HR] 1.37, 95% confidence interval [CI] 1.10-1.72, P = 0.006). There was a trend for a lower bF rate in patients treated with LDR PB when compared with those treated by EBRT ≤ 74 Gy (HR 0.234, 95% CI 0.05-1.03, P = 0.055) in multivariate analysis. In the subgroup of patients with a CAPRA score of 3-5, CAPRA remained predictive of bF as a continuous variable (HR 1.51, 95% CI 1.01-2.27, P = 0.047) in multivariate analysis. The CAPRA score is useful for predicting biochemical recurrence in patients treated for intermediate-risk prostate cancer with EBRT or LDR PB. It could help in treatment decisions. © 2013 The Authors. BJU International © 2013 BJU International.

The effect of low dose rate on metabolomic response to radiation in mice

PubMed Central

Goudarzi, Maryam; Mak, Tytus D.; Chen, Congju; Smilenov, Lubomir B.; Brenner, David J.

2014-01-01

Metabolomics has been shown to have utility in assessing responses to exposure by ionizing radiation (IR) in easily accessible biofluids such as urine. Most studies to date from our laboratory and others have employed γ-irradiation at relatively high dose rates (HDR), but many environmental exposure scenarios will probably be at relatively low dose rates (LDR). There are well-documented differences in the biologic responses to LDR compared to HDR, so an important question is to assess LDR effects at the metabolomics level. Our study took advantage of a modern mass spectrometry approach in exploring the effects of dose rate on the urinary excretion levels of metabolites 2 days after IR in mice. A wide variety of statistical tools were employed to further focus on metabolites, which showed responses to LDR IR exposure (0.00309 Gy/min) distinguishable from those of HDR. From a total of 709 detected spectral features, more than 100 were determined to be statistically significant when comparing urine from mice irradiated with 1.1 or 4.45 Gy to that of sham-irradiated mice 2 days post-exposure. The results of this study show that LDR and HDR exposures perturb many of the same pathways such as TCA cycle and fatty acid metabolism, which also have been implicated in our previous IR studies. However, it is important to note that dose rate did affect the levels of particular metabolites. Differences in urinary excretion levels of such metabolites could potentially be used to assess an individual's exposure in a radiobiological event and thus would have utility for both triage and injury assessment. PMID:25047638

Long-term low-dose α-particle enhanced the potential of malignant transformation in human bronchial epithelial cells through MAPK/Akt pathway

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Weili; Xiao, Linlin; Dong, Chen

2014-05-09

Highlights: • Multi-exposures of 25 mGy α-ray enhanced cell proliferation, adhesion, and invasion. • MAPK/Akt but not JNK/P66 was positively correlated with cell invasive phenotypes. • LDR of α-irradiation triggers cell malignant transformation through MAPK/Akt. - Abstract: Since the wide usage of ionizing radiation, the cancer risk of low dose radiation (LDR) (<0.1 Gy) has become attractive for a long time. However, most results are derived from epidemiologic studies on atomic-bomb survivors and nuclear accidents surrounding population, and the molecular mechanism of this risk is elusive. To explore the potential of a long-term LDR-induced malignant transformation, human bronchial epithelial cellsmore » Beas-2B were fractionally irradiated with 0.025 Gy α-particles for 8 times in total and then further cultured for 1–2 months. It was found that the cell proliferation, the abilities of adhesion and invasion, and the protein expressions of p-ERK, p-Akt, especially p-P38 were not only increased in the multiply-irradiated cells but also in their offspring 1–2 months after the final exposure, indicating high potentiality of cell malignant transformation. On opposite, the expressions of p-JNK and p-P66 were diminished in the subcultures of irradiated cells and thus may play a role of negative regulation in canceration. When the cells were transferred with p38 siRNA, the LDR-induced enhancements of cell adhesion and invasion were significantly reduced. These findings suggest that long-term LDR of α-particles could enhance the potential of malignant transformation incidence in human bronchial epithelial cells through MAPK/Akt pathway.« less

Tracking and data relay satellite system configuration and tradeoff study. Volume 5: TDRS spacecraft design, part 1

NASA Technical Reports Server (NTRS)

1972-01-01

A dual spin stabilized TDR spacecraft design is presented for low data rate (LDR) and medium data rate (MDR) user spacecraft telecommunication relay service. The relay satellite provides command and data return channels for unmanned users together with duplex voice and data communication channels for manned user spacecraft. TDRS/ground links are in the Ku band. Command links are provided at UHF for LDR users and S band for MDR users. Voice communication channels are provided at UHF/VHF for LDR users and at S band for MDR users. The spacecraft is designed for launch on the Delta 2914 with system deployment planned for 1978. This volume contains a description of the overall TDR spacecraft configuration, a detailed description of the spacecraft subsystems, a reliability analysis, and a product effectiveness plan.

Dose Rate Switching Technique on ELDRS-Free Bipolar Devices

NASA Astrophysics Data System (ADS)

Boch, J.; Michez, A.; Rousselet, M.; Dhombres, S.; Touboul, A. D.; Vaillé, J.-R.; Dusseau, L.; Lorfèvre, E.; Chatry, N.; Sukhaseum, N.; Saigné, F.

2016-08-01

The Switched Dose Rate technique is investigated when devices do not exhibit ELDRS. Experimental data and modeling results are presented and discussed in terms of hardness assurance. It is shown, for devices that do not show ELDRS, that a time is required before the switched devices reach the LDR curve. As a solution, it is proposed to apply an annealing between the HDR and the LDR irradiation.

Assembly considerations for large reflectors

NASA Technical Reports Server (NTRS)

Bush, H.

1988-01-01

The technologies developed at LaRC in the area of erectable instructures are discussed. The information is of direct value to the Large Deployable Reflector (LDR) because an option for the LDR backup structure is to assemble it in space. The efforts in this area, which include development of joints, underwater assembly simulation tests, flight assembly/disassembly tests, and fabrication of 5-meter trusses, led to the use of the LaRC concept as the baseline configuration for the Space Station Structure. The Space Station joint is linear in the load and displacement range of interest to Space Station; the ability to manually assemble and disassemble a 45-foot truss structure was demonstrated by astronauts in space as part of the ACCESS Shuttle Flight Experiment. The structure was built in 26 minutes 46 seconds, and involved a total of 500 manipulations of untethered hardware. Also, the correlation of the space experience with the neutral buoyancy simulation was very good. Sections of the proposed 5-meter bay Space Station truss have been built on the ground. Activities at LaRC have included the development of mobile remote manipulator systems (which can traverse the Space Station 5-meter structure), preliminary LDR sun shield concepts, LDR construction scenarios, and activities in robotic assembly of truss-type structures.

Salvage low-dose-rate 125I partial prostate brachytherapy after dose-escalated external beam radiotherapy

PubMed Central

Chang, Lynn

2014-01-01

Purpose To report outcomes on 5 patients treated with salvage partial low-dose-rate (LDR) 125-iodine (125I) permanent prostate seed brachytherapy (BT) for biopsy-proven locally persistent prostate cancer, following failure of dose-escalated external beam radiotherapy (EBRT). Material and methods A retrospective review of the Fox Chase Cancer Center prostate cancer database identified five patients treated with salvage partial LDR 125I seed implant for locally persistent disease following dose-escalated EBRT to 76-84 Gy in 2 Gy per fraction equivalent. All patients had post-EBRT biopsies confirming unilateral locally persistent prostate cancer. Pre-treatment, EBRT and BT details, as well as post-treatment characteristics were documented and assessed. Results The median follow-up post-implant was 41 months. All five patients exhibited low acute genitourinary and gastrointestinal toxicities. Increased erectile dysfunction was noted in three patients. There were no biochemical failures following salvage LDR 125I seed BT to date, with a median post-salvage PSA of 0.4 ng/mL. Conclusions In carefully selected patients with local persistence of disease, partial LDR 125I permanent prostate seed implant appears to be a feasible option for salvage local therapy with an acceptable toxicity profile. Further study is needed to determine long-term results of this approach. PMID:25337135

Nonlinear dose response model with repair and repair suppression

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leonard, B.E.

1996-12-31

In March 1996, the Health Physics Society issued a position statement supporting a nonlinear threshold (NLT) concept for radiation risk at low-dose/low-dose-rate (LD/LDR) levels. This action was after receipt of an overwhelming consensus from world-renown radiobiologists and is contrary to the opinions of the United Nations Scientific Committee on Effects of Atomic Radiation, the National Research Council Committee on the Biological Effects of Ionizing Radiations, and U.S. Environmental Protection Agency. Alvarez and others have called for a new NLT model for radiation risk. Two mathematical models have historically been used to describe cell survival experimental results. Each provides the abilitymore » to account for the shoulder observed in cell survival curves, predominantly for low-linear energy transfer (LET) radiation, and the wide variation in radio sensitivity of cell species and particular phase of the mitotic cycle. Only Kellerer and Rossi, Elkind and Whitmore, and Green and Burki have proposed modified models explicitly incorporating radiobiological repair and departing from LNT. None of these were subsequently used with any extent of success in cell survival analysis. The author reports initial work on a program to reexamine radiobiology research exhibiting repair processes at LD/LDR levels.« less

Large Deployable Reflector Science and Technology Workshop. Volume 3: Systems and Technology Assessment

NASA Technical Reports Server (NTRS)

Leidich, C. A. (Editor); Pittman, R. B. (Editor)

1984-01-01

The results of five technology panels which convened to discuss the Large Deployable Reflector (LDR) are presented. The proposed LDR is a large, ambient-temperature, far infrared/submillimeter telescope designed for space. Panel topics included optics, materials and structures, sensing and control, science instruments, and systems and missions. The telescope requirements, the estimated technology levels, and the areas in which the generic technology work has to be augmented are enumerated.

Experimental test of liquid droplet radiator performance

NASA Astrophysics Data System (ADS)

Mattick, A. T.; Simon, M. A.

The liquid droplet radiator (LDR) is a heat rejection system for space power systems wherein an array of heated liquid droplets radiates energy directly to space. The use of submillimeter droplets provides large radiating area-to-mass ratio, resulting in radiator systems which are several times lighter than conventional solid surface radiators. An experiment is described in which the power radiated by an array of 2300 streams of silicone oil droplets is measured to test a previously developed theory of the LDR radiation process. This system would be capable of rejecting several kW of heat in space. Furthermore, it would be suitable as a modular unit of an LDR designed for 100-kW power levels. The experiment provided confirmation of the theoretical dependence of droplet array emissivity on optical depth. It also demonstrated the ability to create an array of more than 1000 droplet streams having a divergence less than 1 degree.

Experimental test of liquid droplet radiator performance

NASA Technical Reports Server (NTRS)

Mattick, A. T.; Simon, M. A.

1987-01-01

The liquid droplet radiator (LDR) is a heat rejection system for space power systems wherein an array of heated liquid droplets radiates energy directly to space. The use of submillimeter droplets provides large radiating area-to-mass ratio, resulting in radiator systems which are several times lighter than conventional solid surface radiators. An experiment is described in which the power radiated by an array of 2300 streams of silicone oil droplets is measured to test a previously developed theory of the LDR radiation process. This system would be capable of rejecting several kW of heat in space. Furthermore, it would be suitable as a modular unit of an LDR designed for 100-kW power levels. The experiment provided confirmation of the theoretical dependence of droplet array emissivity on optical depth. It also demonstrated the ability to create an array of more than 1000 droplet streams having a divergence less than 1 degree.

Androgen Suppression Combined with Elective Nodal and Dose Escalated Radiation Therapy (the ASCENDE-RT Trial): An Analysis of Survival Endpoints for a Randomized Trial Comparing a Low-Dose-Rate Brachytherapy Boost to a Dose-Escalated External Beam Boost for High- and Intermediate-risk Prostate Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morris, W. James, E-mail: jmorris@bccancer.bc.ca; BC Cancer Agency–Vancouver Centre, Vancouver, British Columbia; Tyldesley, Scott

Purpose: To report the primary endpoint of biochemical progression-free survival (b-PFS) and secondary survival endpoints from ASCENDE-RT, a randomized trial comparing 2 methods of dose escalation for intermediate- and high-risk prostate cancer. Methods and Materials: ASCENDE-RT enrolled 398 men, with a median age of 68 years; 69% (n=276) had high-risk disease. After stratification by risk group, the subjects were randomized to a standard arm with 12 months of androgen deprivation therapy, pelvic irradiation to 46 Gy, followed by a dose-escalated external beam radiation therapy (DE-EBRT) boost to 78 Gy, or an experimental arm that substituted a low-dose-rate prostate brachytherapy (LDR-PB) boost. Of the 398more » trial subjects, 200 were assigned to DE-EBRT boost and 198 to LDR-PB boost. The median follow-up was 6.5 years. Results: In an intent-to-treat analysis, men randomized to DE-EBRT were twice as likely to experience biochemical failure (multivariable analysis [MVA] hazard ratio [HR] 2.04; P=.004). The 5-, 7-, and 9-year Kaplan-Meier b-PFS estimates were 89%, 86%, and 83% for the LDR-PB boost versus 84%, 75%, and 62% for the DE-EBRT boost (log-rank P<.001). The LDR-PB boost benefited both intermediate- and high-risk patients. Because the b-PFS curves for the treatment arms diverge sharply after 4 years, the relative advantage of the LDR-PB should increase with longer follow-up. On MVA, the only variables correlated with reduced overall survival were age (MVA HR 1.06/y; P=.004) and biochemical failure (MVA HR 6.30; P<.001). Although biochemical failure was associated with increased mortality and randomization to DE-EBRT doubled the rate of biochemical failure, no significant overall survival difference was observed between the treatment arms (MVA HR 1.13; P=.62). Conclusions: Compared with 78 Gy EBRT, men randomized to the LDR-PB boost were twice as likely to be free of biochemical failure at a median follow-up of 6.5 years.« less

Specific, sensitive, and rapid assay for human immunodeficiency virus type 1 pol mutations associated with resistance to zidovudine and didanosine.

PubMed Central

Frenkel, L M; Wagner, L E; Atwood, S M; Cummins, T J; Dewhurst, S

1995-01-01

The effectiveness of antiretroviral therapy may be limited by the development of human immunodeficiency virus type 1 (HIV-1) resistance. Monitoring for resistance will perhaps allow changes in therapy prior to deterioration in the patient's clinical or immunologic status. Our objective was to develop a rapid, specific, and sensitive genotypic assay for HIV-1 resistance to zidovudine (ZDV) and didanosine (ddI) which is simple to perform. In our assay the DNA of HIV-1 pol was amplified by PCR using two sets of nested oligonucleotide primers. Mutations of reverse transcriptase (RT) encoding amino acids (aa) 74 and 41, 70, and 215 which have been associated with HIV-1 resistance to ddI and ZDV, respectively, were detected with a ligase detection reaction (LDR) and indicated colorimetrically. The RT genotypes of 35 patient specimens (140 codons) blindly assessed for these mutations were in agreement by PCR-LDR and by dideoxynucleotide sequencing. To evaluate the limits of the assay, other specimens with mutations close to the ligation site were evaluated by PCR-LDR. The assay was sensitive and specific for all specimens except when mutations occurred within 2 bases on either side of the ligation site. In summary, this PCR-LDR assay specifically, sensitively, and rapidly detected pol mutations (RT aa 74, 41, 70, and 215) associated with HIV-1 resistance to ddI and ZDV. PMID:7714190

A vertically-stacked, polymer, microfluidic point mutation analyzer: Rapid, high accuracy detection of low-abundance K-ras mutations

PubMed Central

Han, Kyudong; Lee, Tae Yoon; Nikitopoulos, Dimitris E.; Soper, Steven A.; Murphy, Michael C.

2011-01-01

Recognition of point mutations in the K-ras gene can be used for the clinical management of several types of cancers. Unfortunately, several assay and hardware concerns must be addressed to allow users not well-trained in performing molecular analyses the opportunity to undertake these measurements. To provide for a larger user-base for these types of molecular assays, a vertically-stacked microfluidic analyzer with a modular architecture and process automation was developed. The analyzer employed a primary PCR coupled to an allele-specific ligase detection reaction (LDR). Each functional device, including continuous flow thermal reactors for the PCR and LDR, passive micromixers and ExoSAP-IT® purification, was designed and tested. Individual devices were fabricated in polycarbonate using hot embossing and assembled using adhesive bonding for system assembly. The system produced LDR products from a DNA sample in ~1 h, an 80% reduction in time compared to conventional bench-top instrumentation. Purifying the post-PCR products with the ExoSAP-IT® enzyme led to optimized LDR performance minimizing false positive signals and producing reliable results. Mutant alleles in genomic DNA were quantified to the level of 0.25 ng of mutant DNA in 50 ng of wild-type DNA for a 25 μL sample, equivalent to DNA from 42 mutant cells. PMID:21771577

Dose and dose rate effects of whole-body gamma-irradiation: I. Lymphocytes and lymphoid organs

NASA Technical Reports Server (NTRS)

Pecaut, M. J.; Nelson, G. A.; Gridley, D. S.

2001-01-01

The major goal of part I of this study was to compare varying doses and dose rates of whole-body gamma-radiation on lymphoid cells and organs. C57BL/6 mice (n = 75) were exposed to 0, 0.5, 1.5, and 3.0 Gy gamma-rays (60Co) at 1 cGy/min (low-dose rate, LDR) and 80 cGy/min (high-dose rate, HDR) and euthanized 4 days later. A significant dose-dependent loss of spleen mass was observed with both LDR and HDR irradiation; for the thymus this was true only with HDR. Decreasing leukocyte and lymphocyte numbers occurred with increasing dose in blood and spleen at both dose rates. The numbers (not percentages) of CD3+ T lymphocytes decreased in the blood in a dose-dependent manner at both HDR and LDR. Splenic T cell counts decreased with dose only in HDR groups; percentages increased with dose at both dose rates. Dose-dependent decreases occurred in CD4+ T helper and CD8+ T cytotoxic cell counts at HDR and LDR. In the blood the percentages of CD4+ cells increased with increasing dose at both dose rates, whereas in the spleen the counts decreased only in the HDR groups. The percentages of the CD8+ population remained stable in both blood and spleen. CD19+ B cell counts and percentages in both compartments declined markedly with increasing HDR and LDR radiation. NK1.1+ natural killer cell numbers and proportions remained relatively stable. Overall, these data indicate that the observed changes were highly dependent on the dose, but not dose rate, and that cells in the spleen are more affected by dose rate than those in blood. The results also suggest that the response of lymphocytes in different body compartments may be variable.

GSTP1 Loss results in accumulation of oxidative DNA base damage and promotes prostate cancer cell survival following exposure to protracted oxidative stress.

PubMed

Mian, Omar Y; Khattab, Mohamed H; Hedayati, Mohammad; Coulter, Jonathan; Abubaker-Sharif, Budri; Schwaninger, Julie M; Veeraswamy, Ravi K; Brooks, James D; Hopkins, Lisa; Shinohara, Debika Biswal; Cornblatt, Brian; Nelson, William G; Yegnasubramanian, Srinivasan; DeWeese, Theodore L

2016-02-01

Epigenetic silencing of glutathione S-transferase π (GSTP1) is a hallmark of transformation from normal prostatic epithelium to adenocarcinoma of the prostate. The functional significance of this loss is incompletely understood. The present study explores the effects of restored GSTP1 expression on glutathione levels, accumulation of oxidative DNA damage, and prostate cancer cell survival following oxidative stress induced by protracted, low dose rate ionizing radiation (LDR). GSTP1 protein expression was stably restored in LNCaP prostate cancer cells. The effect of GSTP1 restoration on protracted LDR-induced oxidative DNA damage was measured by GC-MS quantitation of modified bases. Reduced and oxidized glutathione levels were measured in control and GSTP1 expressing populations. Clonogenic survival studies of GSTP1- transfected LNCaP cells after exposure to protracted LDR were performed. Global gene expression profiling and pathway analysis were performed. GSTP1 expressing cells accumulated less oxidized DNA base damage and exhibited decreased survival compared to control LNCaP-Neo cells following oxidative injury induced by protracted LDR. Restoration of GSTP1 expression resulted in changes in modified glutathione levels that correlated with GSTP1 protein levels in response to protracted LDR-induced oxidative stress. Survival differences were not attributable to depletion of cellular glutathione stores. Gene expression profiling and pathway analysis following GSTP1 restoration suggests this protein plays a key role in regulating prostate cancer cell survival. The ubiquitous epigenetic silencing of GSTP1 in prostate cancer results in enhanced survival and accumulation of potentially promutagenic DNA adducts following exposure of cells to protracted oxidative injury suggesting a protective, anti-neoplastic function of GSTP1. The present work provides mechanistic backing to the tumor suppressor function of GSTP1 and its role in prostate carcinogenesis. © 2015 Wiley Periodicals, Inc.

GSTP1 Loss Results in Accumulation of Oxidative DNA Base Damage and Promotes Prostate Cancer Cell Survival Following Exposure to Protracted Oxidative Stress

PubMed Central

Mian, Omar Y.; Khattab, Mohamed H.; Hedayati, Mohammad; Coulter, Jonathan; Abubaker-Sharif, Budri; Schwaninger, Julie M.; Veeraswamy, Ravi K.; Brooks, James D.; Hopkins, Lisa; Shinohara, Debika Biswal; Cornblatt, Brian; Nelson, William G.; Yegnasubramanian, Srinivasan; DeWeese, Theodore L.

2016-01-01

BACKGROUND Epigenetic silencing of glutathione S-transferase π (GSTP1) is a hallmark of transformation from normal prostatic epithelium to adenocarcinoma of the prostate. The functional significance of this loss is incompletely understood. The present study explores the effects of restored GSTP1 expression on glutathione levels, accumulation of oxidative DNA damage, and prostate cancer cell survival following oxidative stress induced by protracted, low dose rate ionizing radiation (LDR). METHODS GSTP1 protein expression was stably restored in LNCaP prostate cancer cells. The effect of GSTP1 restoration on protracted LDR-induced oxidative DNA damage was measured by GC-MS quantitation of modified bases. Reduced and oxidized glutathione levels were measured in control and GSTP1 expressing populations. Clonogenic survival studies of GSTP1-transfected LNCaP cells after exposure to protracted LDR were performed. Global gene expression profiling and pathway analysis were performed. RESULTS GSTP1 expressing cells accumulated less oxidized DNA base damage and exhibited decreased survival compared to control LNCaP-Neo cells following oxidative injury induced by protracted LDR. Restoration of GSTP1 expression resulted in changes in modified glutathione levels that correlated with GSTP1 protein levels in response to protracted LDR-induced oxidative stress. Survival differences were not attributable to depletion of cellular glutathione stores. Gene expression profiling and pathway analysis following GSTP1 restoration suggests this protein plays a key role in regulating prostate cancer cell survival. CONCLUSIONS The ubiquitous epigenetic silencing of GSTP1 in prostate cancer results in enhanced survival and accumulation of potentially promutagenic DNA adducts following exposure of cells to protracted oxidative injury suggesting a protective, anti-neoplastic function of GSTP1. The present work provides mechanistic backing to the tumor suppressor function of GSTP1 and its role in prostate carcinogenesis. PMID:26447830

Multiplex quantification of 16S rDNA of predominant bacteria group within human fecal samples by polymerase chain reaction--ligase detection reaction (PCR-LDR).

PubMed

Li, Kai; Chen, Bei; Zhou, Yuxun; Huang, Rui; Liang, Yinming; Wang, Qinxi; Xiao, Zhenxian; Xiao, Junhua

2009-03-01

A new method, based on ligase detection reaction (LDR), was developed for quantitative detection of multiplex PCR amplicons of 16S rRNA genes present in complex mixtures (specifically feces). LDR has been widely used in single nucleotide polymorphism (SNP) assay but never applied for quantification of multiplex PCR products. This method employs one pair of DNA probes, one of which is labeled with fluorescence for signal capture, complementary to the target sequence. For multiple target sequence analysis, probes were modified with different lengths of polyT at the 5' end and 3' end. Using a DNA sequencer, these ligated probes were separated and identified by size and dye color. Then, relative abundance of target DNA were normalized and quantified based on the fluorescence intensities and exterior size standards. 16S rRNA gene of three preponderant bacteria groups in human feces: Clostridium coccoides, Bacteroides and related genera, and Clostridium leptum group, were amplified and cloned into plasmid DNA so as to make standard curves. After PCR-LDR analysis, a strong linear relationship was found between the florescence intensity and the diluted plasmid DNA concentrations. Furthermore, based on this method, 100 human fecal samples were quantified for the relative abundance of the three bacterial groups. Relative abundance of C. coccoides was significantly higher in elderly people in comparison with young adults, without gender differences. Relative abundance of Bacteroides and related genera and C. leptum group were significantly higher in young and middle aged than in the elderly. Regarding the whole set of sample, C. coccoides showed the highest relative abundance, followed by decreasing groups Bacteroides and related genera, and C. leptum. These results imply that PCR-LDR can be feasible and flexible applied to large scale epidemiological studies.

Brachytherapy for cervix cancer: low-dose rate or high-dose rate brachytherapy – a meta-analysis of clinical trials

PubMed Central

Viani, Gustavo A; Manta, Gustavo B; Stefano, Eduardo J; de Fendi, Ligia I

2009-01-01

Background The literature supporting high-dose rate brachytherapy (HDR) in the treatment of cervical carcinoma derives primarily from retrospective series. However, controversy still persists regarding the efficacy and safety of HDR brachytherapy compared to low-dose rate (LDR) brachytherapy, in particular, due to inadequate tumor coverage for stage III patients. Whether LDR or HDR brachytherapy produces better results for these patients in terms of survival rate, local control rate and the treatment complications remain controversial. Methods A meta-analysis of RCT was performed comparing LDR to HDR brachytherapy for cervix cancer treated for radiotherapy alone. The MEDLINE, EMBASE, CANCERLIT and Cochrane Library databases, as well as abstracts published in the annual proceedings were systematically searched. We assessed methodological quality for each outcome by grading the quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. We used "recommend" for strong recommendations, and "suggest" for weak recommendations. Results Pooled results from five randomized trials (2,065 patients) of HDR brachytherapy in cervix cancer showed no significant increase of mortality (p = 0.52), local recurrence (p = 0.68), or late complications (rectal; p = 0.7, bladder; p = 0.95 or small intestine; p = 0.06) rates as compared to LDR brachytherapy. In the subgroup analysis no difference was observed for overall mortality and local recurrence in patients with clinical stages I, II and III. The quality of evidence was low for mortality and local recurrence in patients with clinical stage I, and moderate for other clinical stages. Conclusion Our meta-analysis shows that there are no differences between HDR and LDR for overall survival, local recurrence and late complications for clinical stages I, II and III. By means of the GRADE system, we recommend the use of HDR for all clinical stages of cervix cancer. PMID:19344527

SU-E-T-259: Development of a Primary Standard for LDR Brachytherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shen, H; McEwen, M

Purpose: The National Research Council initiated a program in 2012 to develop a primary standard to calibrate I-125 and Pd-103 sources used for LDR brachytherapy and disseminate this through calibration services to Canadian users. This will simplify procedures as Canadian cancer centres currently have to ship instruments to the US. Methods: The standard is based on a commercial version of the wide-angle free air chamber (WAFAC) pioneered by NIST. Significant enhancements were implemented to improve signal-to-noise and measurement reproducibility and eliminate electric field effects. Validation of this ionization chamber was then carried out in a low-energy X -ray beam (∼more » 31 keV) where the dose rate had been previously established using the existing NRC primary standard free-air chamber. As a final component of this initial testing, measurements were made with a set of I-125 seeds (with air kerma strength traceable to NIST). Results: Excellent agreement of the two NRC free-air chambers was obtained within the combined standard uncertainty of 0.5 %. However, it was found that the WAFAC response is very sensitive to the beam geometry (distance from the source, diameter of the beam-defining aperture, etc) and Monte Carlo calculations, carried out to evaluate these geometry corrections, have confirmed the experimental results. The results for the seed measurements indicated a precision of better than 1 % is achievable for a reasonable acquisition time and the air kerma strength agreed with the manufacturer (NIST-traceable) value within 2 %. Conclusion: The prototype primary standard for LDR brachytherapy has met accuracy target of 3 % for the determination of air kerma strength. Work is ongoing to refine operation of the device and develop the calibration protocol for clinical users, with an anticipated launch of a calibration service in late 2015.« less

Low-dose radiation suppresses Pokemon expression under hypoxic conditions.

PubMed

Kim, Seung-Whan; Yu, Kweon; Shin, Kee-Sun; Kwon, Kisang; Hwang, Tae-Sik; Kwon, O-Yu

2014-01-01

Our previous data demonstrated that CoCl2-induced hypoxia controls endoplasmic reticulum (ER) stress-associated and other intracellular factors. One of them, the transcription factor Pokemon, was differentially regulated by low-dose radiation (LDR). There are limited data regarding how this transcription factor is involved in expression of the unfolded protein response (UPR) under hypoxic conditions. The purpose of this study was to obtain clues on how Pokemon is involved in the UPR. Pokemon was selected as a differentially expressed gene under hypoxic conditions; however, its regulation was clearly repressed by LDR. It was also demonstrated that both expression of ER chaperones and ER stress sensors were affected by hypoxic conditions, and the same results were obtained when cells in which Pokemon was up- or down-regulated were used. The current state of UPR and LDR research associated with the Pokemon pathway offers an important opportunity to understand the oncogenesis, senescence, and differentiation of cells, as well as to facilitate introduction of new therapeutic radiopharmaceuticals.

LDR structural experiment definition

NASA Technical Reports Server (NTRS)

Russell, Richard A.; Gates, Richard M.

1988-01-01

A study was performed to develop the definition of a structural flight experiment for a large precision segmented reflector that would utilize the Space Station. The objective of the study was to use the Large Deployable Reflector (LDR) baseline configuration for focusing on experiment definition activity which would identify the Space Station accommodation requirements and interface constraints. Results of the study defined three Space Station based experiments to demonstrate the technologies needed for an LDR type structure. The basic experiment configurations are the same as the JPL baseline except that the primary mirror truss is 10 meters in diameter instead of 20. The primary objectives of the first experiment are to construct the primary mirror support truss and to determine its structural and thermal characteristics. Addition of the optical bench, thermal shield and primary mirror segments and alignment of the optical components occur on the second experiment. The structure will then be moved to the payload pointing system for pointing, optical control and scientific optical measurement for the third experiment.

Estimating surface hardening profile of blank for obtaining high drawing ratio in deep drawing process using FE analysis

NASA Astrophysics Data System (ADS)

Tan, C. J.; Aslian, A.; Honarvar, B.; Puborlaksono, J.; Yau, Y. H.; Chong, W. T.

2015-12-01

We constructed an FE axisymmetric model to simulate the effect of partially hardened blanks on increasing the limiting drawing ratio (LDR) of cylindrical cups. We partitioned an arc-shaped hard layer into the cross section of a DP590 blank. We assumed the mechanical property of the layer is equivalent to either DP980 or DP780. We verified the accuracy of the model by comparing the calculated LDR for DP590 with the one reported in the literature. The LDR for the partially hardened blank increased from 2.11 to 2.50 with a 1 mm depth of DP980 ring-shaped hard layer on the top surface of the blank. The position of the layer changed with drawing ratios. We proposed equations for estimating the inner and outer diameters of the layer, and tested its accuracy in the simulation. Although the outer diameters fitted in well with the estimated line, the inner diameters are slightly less than the estimated ones.

Concept Evaluation of the Heterogeneous Data Proximity Tool at the C4ISR Network Modernization Event FY12

DTIC Science & Technology

2014-01-01

5 No 2 of 5 2 None 4 of 5 4 of 5 4 of 5 2 21 11B PV2 SAW 0.75 No 5 of 5 0 None 5 of 5 3 of 5 3 of 5 3 26 11B SGT Squad ldr . 5 No 4 of 5 2 None 4 of...5 3 of 5 3 of 5 4 24 11B SPC Team ldr . 5 No 4 of 5 1 None 4 of 5 4 of 5 3 of 5 5 19 11B PFC Infantryman 1 No 3 of 5 0 None 4 of 5 4 of 5 5 of 5 6...41 11B SGT Squad ldr . 18.5 No 5 of 5 7 Yes 4 of 5 5 of 5 4 of 5 7 52 42A LTC S3 32 No 3 of 5 2 Yes 5 of 5 — 5 of 5 8 21 11B PV2 Infantryman 1 No 4 of

Avatar' remarks on the carbon input threshold in the sloping croplands

NASA Astrophysics Data System (ADS)

Novara, Agata; Gristina, Luciano; García-Díaz, Andrés; Menghin, Riccardo; Cerdà, Artemi

2015-04-01

The erosion processes has been recognized as a major treat to land degradation and to the sustainability of agriculture (Gulati and Rai, 2014; Cerda, 2010). Soil erosion by water causes significant ecological damage; it decreases soil fertility, affecting hydrological properties and soil aggregates stability, nutrients and biological activity and reducing soil carbon. The agricultural land degradation by erosion is, moreover, exacerbated by inappropriate soil management techniques. It is the case of most of Mediterranean vineyards where in addition to environmental factors (high slope, rainfall with high intensity), soil management with continuous tillage and absence of plant cover accelerate erosion process (Novara et al., 2011; Ruiz-Colmenero et al., 2012, Bochet et al., 2010; Ries, 2010; Martín-Moreno et al., 2013). For this reason in the last decades have been developed an alternative soil management such us cover crop under vineyard in order to reduce erosion and improve soil organic carbon level by the increase of carbon input into the soil. The avatar wonder: The loss of Carbon by water under alternative soil management could exceed the total C loss under conventional soil management? Is there a C threshold devised for each terrestrial ecosystem? If C input under alternative management increase, soil will reach a saturation C level? The soil science avatar will show the scenario of a conceptual model applied in a Mediterranean sloping vineyard. Acknowledgements To the "Ministerio de Economía and Competitividad" of Spanish Government for finance the POSTFIRE project (CGL2013- 47862-C2-1-R). The research projects GL2008-02879/BTE, LEDDRA 243857 and PREVENTING AND REMEDIATING DEGRADATION OF SOILS IN EUROPE THROUGH LAND CARE (RECARE)FP7-ENV-2013- supported this research. References Barbera, V., Poma, I., Gristina, L., Novara, A., Egli, M. 2012. Long-term cropping systems and tillage management effects on soil organic carbon stock and steady state level of C sequestration rates in a semiarid environment. Land Degradation & Development, 23: 82- 91. DOI 10.1002/ldr.1055 Barua, A. K., Haque, S. M. S. 2013. Soil characteristics and carbon sequestration potentials of vegetation in degraded hills of Chittagong, Bangladesh. Land Degradation & Development, 24: 63- 71. DOI 10.1002/ldr.1107 Batjes NH. 2014. Projected changes in soil organic carbon stocks upon adoption of recommended soil and water practices in teh Upper Tana River Catchment, Kenia. Land Degradation and Development, 25, 278-287. DOI: 10.1002/ldr.2141 Beatriz Lozano-García and Luis Parras-Alcántara 2014 VARIATION IN SOIL ORGANIC CARBON AND NITROGEN STOCKS ALONG A TOPOSEQUENCE IN A TRADITIONAL MEDITERRANEAN OLIVE GROVE Land Degradation and development, 25, 297-304 | DOI: 10.1002/ldr.2284 Cerdà, A., Flanagan, D.C., le Bissonnais, Y., Boardman, J. 2009. Soil Erosion and Agriculture. Soil and Tillage Research, 107-108. doi:10.1016/j.still.2009.10.006 Cerdà, A., Giménez-Morera, A., Bodí, M.B. 2009. Soil and water losses from new citrus orchards growing on sloped soils in the western Mediterranean basin. Earth Surface Processes and Landforms, 34, 1822-1830. DOI: 10.1002/esp.1889 Debasish-Saha, S.S. Kukal and S.S. Bawa, 2014. SOIL ORGANIC CARBON STOCK AND FRACTIONS IN RELATION TO LAND USE AND SOIL DEPTH IN THE DEGRADED SHIWALIKS HILLS OF LOWER HIMALAYAS Land Degradation and Development, 25, 407-416. DOI: 10.1002/ldr.2151 Debasish-Saha, S.S. Kukal and S.S. Bawa, 2014. SOIL ORGANIC CARBON STOCK AND FRACTIONS IN RELATION TO LAND USE AND SOIL DEPTH IN THE DEGRADED SHIWALIKS HILLS OF LOWER HIMALAYAS Land Degradation and Development, 25, 407-416. DOI: 10.1002/ldr.2151 García-Orenes, F., Guerrero, C., Roldán, A.,Mataix-Solera, J., Cerdà, A., Campoy, M., Zornoza, R., Bárcenas, G., Caravaca. F. 2010. Soil microbial biomass and activity under different agricultural management systems in a semiarid Mediterranean agroecosystem. Soil and Tillage Research. 109 (2): 110-115. 10.1016/j.still.2010.05.005 García-Orenes, F., Roldán, A., Mataix-Solera, J., Cerdà, A., Campoy, M., Arcenegui, V., Caravaca, F. 2012 Soil structural stability and erosion rates influenced by agricultural management practices in a semi-arid Mediterranean agro-ecosystem. Soil Use and Management 28(4): 571-579. DOI: 10.1111/j.1475-2743.2012.00451.x Guzman, J.G., Lal, R., Byrd, S., Apfelbaum, S.I., and Thompson, L. Carbon life cycle assessment for prairie as a crop in reclaimed mine land. Land Degradation and Development. 2014. DOI: 10.1002/ldr.2291 ieskovský J, Kenderessy. P. Modelling the effect of vegetation cover and different tillage practices on soil erosion in vineyards: a case study en Vráble (Slovakia) using WATEM/SEDEM. Land Degradation and Development, 25, 288-296. DOI: 10.1002/ldr.2162.2014. Jaiarree S, Chidthaisong A, Tangtham N, Polprasert C, Sarobol E, Tyler SC. 2014. Carbon Budget and sequestration potential in a sandy soil treated with compost. Land Degradation and Development 25: 120-129 Laudicina, V. A., Novara, A., Barbera, V., Egli, M., & Badalucco, L. (2014). LONG-TERM TILLAGE AND CROPPING SYSTEM EFFECTS ON CHEMICAL AND BIOCHEMICAL CHARACTERISTICS OF SOIL ORGANIC MATTER IN A MEDITERRANEAN SEMIARID ENVIRONMENT. Land Degradation & Development. DOI: 10.1002/ldr.2293 Leh, M., Bajwa, S., Chaubey, I. 2013. Impact of land use change on erosion risk: and integrated remote sensing geopraphic information system and modeling methodology. Land Degradation & Development, 24: 409- 421. DOI 10.1002/ldr.1137 Mandal, D., Sharda, V. N. Appraisal of soil erosion risk in the Eastern Himalayan region of India for soil conservation planning. Land Degradation & Development, 24: 430-437. 2013. DOI 10.1002/ldr.1139 Novara, A., Gristina, L., Bodì, M.B., Cerdà, A. 2011.The impact of fire on redistribution of soil organic matter on a Mediterranean hillslope under maquia vegetation type. Land Degradation and Development, 2: 530 - 536.DOI: 10.1002/ldr Novara, A., Gristina, L., Guaitoli, F., Santoro, A. and Cerdà, A. 2013. Managing soil nitrate with cover crops and buffer strips in Si cilian vineyards. Solid Earth, 4, 255-262. DOI:10.5194/se-4-255-2013. Q. Y. Li, H. Y. Fang, L. Y. Sun and Q. G. Cai 2014 USING THE 137Cs TECHNIQUE TO STUDY THE EFFECT OF SOIL REDISTRIBUTION ON SOIL ORGANIC CARBON AND TOTAL NITROGEN STOCKS IN AN AGRICULTURAL CATCHMENT OF NORTHEAST CHINA Land Degradation and development 25 350-359 DOI: 10.1002/ldr.2 R. C. Fialho and Y. L. Zinn 2014. CHANGES IN SOIL ORGANIC CARBON UNDER EUCALYPTUS PLANTATIONS IN BRAZIL: A COMPARATIVE ANALYSIS. Land Degradation and Development, 25, 428-437. | DOI: 10.1002/ldr.2158 Yan-Gui, S., Xin-Rong, L., Ying-Wu, C., Zhi-Shan, Z., and Yan, L. 2013. Carbon fixaton of cyanobacterial-algal crusts after desert fixation and its implication to soil organic matter accumulation in Desert. Land Degradation & Development, 24: 342- 349. DOI 10.1002/ldr.1131 Zhao, G., Mu, X., Wen, Z., Wang, F., and Gao, P. Soil erosion, conservation, and Eco-environment changes in the Loess Plateau of China. Land Degradation & Development, 24: 499- 510. 2013. DOI 10.1002/ldr.2246

Control of optical systems

NASA Technical Reports Server (NTRS)

Founds, D.

1988-01-01

Some of the current and planned activities at the Air Force Systems Command in structures and controls for optical-type systems are summarized. Many of the activities are contracted to industry; one task is an in-house program which includes a hardware test program. The objective of the in-house program, referred to as the Aluminum Beam Expander Structure (ABES), is to address issues involved in on-orbit system identification. The structure, which appears similar to the LDR backup structure, is about 35 feet tall. The activity to date has been limited to acquisition of about 250 hours of test data. About 30 hours of data per excitation force is gathered in order to obtain sufficient data for a good statistical estimate of the structural parameters. The development of an Integrated Structural Modeling (ISM) computer program is being done by Boeing Aerospace Company. The objective of the contracted effort is to develop a combined optics, structures, thermal, controls, and multibody dynamics simulation code.

Patterns of brachytherapy practice for patients with carcinoma of the cervix (1996-1999): a patterns of care study.

PubMed

Erickson, Beth; Eifel, Patricia; Moughan, Jennifer; Rownd, Jason; Iarocci, Thomas; Owen, Jean

2005-11-15

To analyze the details of brachytherapy practice in patients treated for carcinoma of the cervix in the United States between 1996 and 1999. Radiation facilities were selected from a stratified random sample. Patients were randomly selected from lists of eligible patients treated at each facility. A total of 442 patients' records were reviewed in 59 facilities to obtain data about patients' characteristics, evaluation, tumor extent, and treatment. National estimates were made using weights that reflected the relative contribution of each institution and of each patient within the sampled institutions. From our survey we estimate that 16,375 patients were treated in the United States during this study period. Unless otherwise specified, brachytherapy practice was based on the 408 patients who had their brachytherapy or all their treatment at the surveyed facility. A total of 91.5% of patients underwent brachytherapy at the initial treating institution; 8.5% were referred to a second site for brachytherapy. Forty-two percent of U.S. facilities referred at least some patients to a second facility for brachytherapy. Of U.S. facilities that treated < or =2 eligible patients per year, 61% referred all of their patients to a second facility for brachytherapy or treated with external RT alone; none of the U.S. facilities with larger experience (>2 eligible patients per year) referred all their patients to a second facility for brachytherapy treatment, but 28% referred some patients to an outside facility for brachytherapy. Overall, 94% of patients who completed treatment with curative intent received brachytherapy. Of these patients who had brachytherapy, 77.8%, 13.3%, and 0.9%, respectively, were treated with low-dose-rate (LDR), high-dose-rate (HDR), or a combination of HDR and LDR brachytherapy; 7.9% had interstitial brachytherapy (5.7% LDR and 1.9% HDR, 0.3% mixed). In facilities that treated >2 patients per year, 15.5% and 9.4% of brachytherapy procedures included HDR or interstitial, respectively; in facilities that treated fewer patients, 3.4% had HDR brachytherapy, and only 1.2% had interstitial brachytherapy. Patients treated with LDR intracavitary radiotherapy had one (23.5%), two (74.1%), or three (2.4%) implants. For patients treated with curative intent who completed radiation therapy with LDR intracavitary radiation therapy without hysterectomy, the median brachytherapy dose to Point A was 40.3 Gy, and the median total dose to Point A was 82.9 Gy. Patients were treated with HDR intracavitary radiation therapy using a variety of treatment schedules using 1-2 fractions (7.5%), 3-4 fractions (17.4%), 5-6 fractions (38.5%), 7-9 fractions (33.5%), or 12 fractions (3%). Fraction sizes were <500 cGy (29.5%), 500-<600 (25.2%), 600 (28.1%), >600 (8%), or unknown (9.2%). For patients treated with HDR, the median total dose to Point A (corrected for fraction size using a alpha/beta = 10) was 85.8 Gy (range: 56.2-116.1 Gy). At institutions treating <500 new patients per year, the percentage of patients receiving a brachytherapy dose <40 Gy was significantly higher than at institutions treating > or =500 new patients per year (p < 0.0001). For LDR intracavitary radiation therapy, 5.8% had neither bladder nor rectal doses recorded for any of their implants, whereas in HDR intracavitary radiation therapy, 73.4% had neither bladder nor rectal doses recorded for any of their implants. The median total duration of radiation therapy was identical for patients who had HDR or LDR intracavitary radiation therapy (57 days). For LDR at institutions treating <500 new patients per year, the percentage of patients with treatment duration >56 days was significantly greater than at institutions > or =500 new patients per year (p = 0.002). Of the patients who had LDR intracavitary radiation therapy implants, 65% were treated using tandem and shielded Fletcher-Suit-Delclos colpostats; other patients had mini ovoids (10.9%), cylinders (3.9%), Henschke (3.7%), or other/mixed applicators (16.5%). In contrast, of patients treated with HDR intracavitary radiation therapy, 68.7% had tandem and rings, 18.2% Fletcher-Suit-Delclos ovoids, 7.5% mini ovoids, 2.3% cylinders, and 3.2% other or mixed applicators. The median duration of treatment and median Point A dose were very similar for patients treated with HDR or LDR. Patients with HDR were treated using a variety of treatment schedules. Different applicator types were favored for LDR vs. HDR. Of patients treated with HDR, 73.4% had no brachytherapy bladder or rectal doses recorded, suggesting that full dosimetric calculations were performed only for the first fraction in many institutions. Facility size significantly impacted on referral to another institution for brachytherapy, brachytherapy dose, and treatment duration.

Comparative quantification of human intestinal bacteria based on cPCR and LDR/LCR

PubMed Central

Tang, Zhou-Rui; Li, Kai; Zhou, Yu-Xun; Xiao, Zhen-Xian; Xiao, Jun-Hua; Huang, Rui; Gu, Guo-Hao

2012-01-01

AIM: To establish a multiple detection method based on comparative polymerase chain reaction (cPCR) and ligase detection reaction (LDR)/ligase chain reaction (LCR) to quantify the intestinal bacterial components. METHODS: Comparative quantification of 16S rDNAs from different intestinal bacterial components was used to quantify multiple intestinal bacteria. The 16S rDNAs of different bacteria were amplified simultaneously by cPCR. The LDR/LCR was examined to actualize the genotyping and quantification. Two beneficial (Bifidobacterium, Lactobacillus) and three conditionally pathogenic bacteria (Enterococcus, Enterobacterium and Eubacterium) were used in this detection. With cloned standard bacterial 16S rDNAs, standard curves were prepared to validate the quantitative relations between the ratio of original concentrations of two templates and the ratio of the fluorescence signals of their final ligation products. The internal controls were added to monitor the whole detection flow. The quantity ratio between two bacteria was tested. RESULTS: cPCR and LDR revealed obvious linear correlations with standard DNAs, but cPCR and LCR did not. In the sample test, the distributions of the quantity ratio between each two bacterial species were obtained. There were significant differences among these distributions in the total samples. But these distributions of quantity ratio of each two bacteria remained stable among groups divided by age or sex. CONCLUSION: The detection method in this study can be used to conduct multiple intestinal bacteria genotyping and quantification, and to monitor the human intestinal health status as well. PMID:22294830

Comparative quantification of human intestinal bacteria based on cPCR and LDR/LCR.

PubMed

Tang, Zhou-Rui; Li, Kai; Zhou, Yu-Xun; Xiao, Zhen-Xian; Xiao, Jun-Hua; Huang, Rui; Gu, Guo-Hao

2012-01-21

To establish a multiple detection method based on comparative polymerase chain reaction (cPCR) and ligase detection reaction (LDR)/ligase chain reaction (LCR) to quantify the intestinal bacterial components. Comparative quantification of 16S rDNAs from different intestinal bacterial components was used to quantify multiple intestinal bacteria. The 16S rDNAs of different bacteria were amplified simultaneously by cPCR. The LDR/LCR was examined to actualize the genotyping and quantification. Two beneficial (Bifidobacterium, Lactobacillus) and three conditionally pathogenic bacteria (Enterococcus, Enterobacterium and Eubacterium) were used in this detection. With cloned standard bacterial 16S rDNAs, standard curves were prepared to validate the quantitative relations between the ratio of original concentrations of two templates and the ratio of the fluorescence signals of their final ligation products. The internal controls were added to monitor the whole detection flow. The quantity ratio between two bacteria was tested. cPCR and LDR revealed obvious linear correlations with standard DNAs, but cPCR and LCR did not. In the sample test, the distributions of the quantity ratio between each two bacterial species were obtained. There were significant differences among these distributions in the total samples. But these distributions of quantity ratio of each two bacteria remained stable among groups divided by age or sex. The detection method in this study can be used to conduct multiple intestinal bacteria genotyping and quantification, and to monitor the human intestinal health status as well.

A survey of current clinical practice in permanent and temporary prostate brachytherapy: 2010 update.

PubMed

Buyyounouski, Mark K; Davis, Brian J; Prestidge, Bradley R; Shanahan, Thomas G; Stock, Richard G; Grimm, Peter D; Demanes, D Jeffrey; Zaider, Marco; Horwitz, Eric M

2012-01-01

To help establish patterns of care and standards of care of interstitial permanent low-dose-rate (LDR) and temporary high-dose-rate brachytherapy for prostate cancer and to compare the results with a similar 1998 American Brachytherapy Society (ABS) survey. A comprehensive questionnaire intended to survey specific details of current clinical brachytherapy practice was provided to the participants of the seventh ABS Prostate Brachytherapy School. Responses were tabulated and descriptive statistics are reported. Sixty-five brachytherapy practitioners responded to the survey. Eighty-nine percent (89%) of respondents performed LDR and 49% perform high-dose-rate brachytherapy. The median number of years of experience for LDR brachytherapists increased from 5 to 10 years over the course of the 12 years since the preceding survey. Compared with the first ABS, a smaller proportion of respondents received formal brachytherapy residency training (43% vs. 56%) or formal "hands-on" brachytherapy training (15% vs. 63%). There has been a marked decline in the utilization of the Mick applicator (Mick Radio-Nuclear Instruments, Inc., Mount Vernon, NY, USA) (60% vs. 28%) and an increase in the use of stranded seeds (40% vs. 11%). Compliance with postimplant dosimetry was higher in the 2010 survey. This survey does suggest an evolution in the practice of LDR brachytherapy since 1998 and aids in identifying aspects that require further progress or investigation. ABS guidelines and other practice recommendations appear to impact the practice of brachytherapy. Copyright © 2012 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

Large Deployable Reflector Technologies for Future European Telecom and Earth Observation Missions

NASA Astrophysics Data System (ADS)

Ihle, A.; Breunig, E.; Dadashvili, L.; Migliorelli, M.; Scialino, L.; van't Klosters, K.; Santiago-Prowald, J.

2012-07-01

This paper presents requirements, analysis and design results for European large deployable reflectors (LDR) for space applications. For telecommunications, the foreseeable use of large reflectors is associated to the continuous demand for improved performance of mobile services. On the other hand, several earth observation (EO) missions can be identified carrying either active or passive remote sensing instruments (or both), in which a large effective aperture is needed e.g. BIOMASS. From the European point of view there is a total dependence of USA industry as such LDRs are not available from European suppliers. The RESTEO study is part of a number of ESA led activities to facilitate European LDR development. This paper is focused on the structural-mechanical aspects of this study. We identify the general requirements for LDRs with special emphasis on launcher accommodation for EO mission. In the next step, optimal concepts for the LDR structure and the RF-Surface are reviewed. Regarding the RF surface, both, a knitted metal mesh and a shell membrane based on carbon fibre reinforced silicon (CFRS) are considered. In terms of the backing structure, the peripheral ring concept is identified as most promising and a large number of options for the deployment kinematics are discussed. Of those, pantographic kinematics and a conical peripheral ring are selected. A preliminary design for these two most promising LDR concepts is performed which includes static, modal and kinematic simulation and also techniques to generate the reflector nets.

Long duration mild temperature hyperthermia and brachytherapy.

PubMed

Armour, E P; Raaphorst, G P

2004-03-01

Combining long duration mild temperature hyperthermia (LDMH) and low dose-rate (LDR) brachytherapy to enhance therapeutic killing of cancer cells was proposed many years ago. The cellular and tumour research that supports this hypothesis is presented in this review. Research describing LDMH interaction with pulsed brachytherapy and high dose-rate brachytherapy using clinically relevant parameters are compared with LDMH/LDR brachytherapy. The mechanism by which LDMH sensitizes LDR has been established as the inhibition of sublethal damage repair. The molecular mechanisms have been shown to involve DNA repair enzymes, but the exact nature of these processes is still under investigation. The relative differences between LDMH interactions with human and rodent cells are presented to help in the understanding of possible roles of LDMH in clinical application. The role of LDMH in modifying tumour blood flow and its possible role in LDR sensitization of tumours is also presented. The positive aspects of LDMH-brachytherapy for clinical application are sixfold; (1) the thermal goals (temperature, time and volume) are achievable with currently available technology, (2) the hyperthermia by itself has no detectable toxic effects, (3) thermotolerance appears to play a minor if any role in radiation sensitization, (4) TER of around 2 can be expected, (5) hypoxic fraction may be decreased due to blood flow modification and (6) simultaneous chemotherapy may also be sensitized. Combined LDMH and brachytherapy is a cancer therapy that has established biological rationale and sufficient technical and clinical advancements to be appropriately applied. This modality is ripe for clinical testing.

Phosphocreatine resynthesis during recovery in different muscles of the exercising leg by 31P-MRS.

PubMed

Yoshida, T; Abe, D; Fukuoka, Y

2013-10-01

To investigate the high-energy phosphate metabolism by (31) P-nuclear magnetic resonance spectroscopy during off-transition of exercise in different muscle groups, such as calf muscles and biceps femoris muscles, seven male long-distance runners (LDR) and nine untrained males (UT) performed both submaximal constant and incremental exercises. The relative exercise intensity was set at 60% of the maximal work rate (60%W max) during both knee flexion and plantar flexion submaximal constant load exercises. The relative areas under the inorganic phosphate (Pi ) and phosphocreatine (PCr) peaks were determined. During the 5-min recovery following the 60%W max, the time constant for the PCr off-kinetics was significantly faster in the plantar flexion (LDR: 17.3 ± 3.6 s, UT: 26.7 ± 6.7 s) than in the knee flexion (LDR: 29.7 ± 4.7 s, UT: 42.7 ± 2.8 s, P < 0.05). In addition, a significantly faster PCr off-kinetics was observed in LDR than in UT for both exercises. The ratio of Pi to PCr (Pi /PCr) during exercise was significantly lower during the plantar flexion than during the knee flexion (P < 0.01). These findings indicated that the calf muscles had relatively higher potential for oxidative capacity than that of biceps femoris muscles with an association of training status. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Clinical evaluation of a medical high dynamic range display

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marchessoux, Cedric, E-mail: cedric.marchessoux@ba

Purpose: Recent new medical displays do have higher contrast and higher luminance but do not have a High Dynamic Range (HDR). HDR implies a minimum luminance value close to zero. A medical HDR display prototype based on two Liquid Crystal layers has been developed. The goal of this study is to evaluate the potential clinical benefit of such display in comparison with a low dynamic range (LDR) display. Methods: The study evaluated the clinical performance of the displays in a search and detection task. Eight radiologists read chest x-ray images some of which contained simulated lung nodules. The study usedmore » a JAFROC (Jacknife Free Receiver Operating Characteristic) approach for analyzing FROC data. The calculated figure of merit (FoM) is the probability that a lesion is rated higher than all rated nonlesions on all images. Time per case and accuracy for locating the center of the nodules were also compared. The nodules were simulated using Samei’s model. 214 CR and DR images [half were “healthy images” (chest nodule-free) and half “diseased images”] were used resulting in a total number of nodules equal to 199 with 25 images with 1 nodule, 51 images with 2 nodules, and 24 images with 3 nodules. A dedicated software interface was designed for visualizing the images for each session. For the JAFROC1 statistical analysis, the study is done per nodule category: all nodules, difficult nodules, and very difficult nodules. Results: For all nodules, the averaged FoM{sub HDR} is slightly higher than FoM{sub LDR} with 0.09% of difference. For the difficult nodules, the averaged FoM{sub HDR} is slightly higher than FoM{sub LDR} with 1.38% of difference. The averaged FoM{sub HDR} is slightly higher than FoM{sub LDR} with 0.71% of difference. For the true positive fraction (TPF), both displays (the HDR and the LDR ones) have similar TPF for all nodules, but looking at difficult and very difficult nodules, there are more TP for the HDR display. The true positive fraction has been also computed in function of the local average luminance around the nodules. For the lowest luminance range, there is more than 30% in favor of the HDR display. For the highest luminance range, there is less than 6% in favor of the LDR display. Conclusions: This study shows the potential benefit of using a HDR display in radiology.« less

Pollution of soils in urban areas in Serbia

NASA Astrophysics Data System (ADS)

Grujic, Gordana; Crnkovic, Dragan; Cerdà, Artemi

2017-04-01

Soil pollution is a world-wide problems that affect rural and urban areas of all the continents (Hu et al., 2015; Mao et al., 2016; Trujillo-González et al., 2016; Elkhatib et al., 2016; Roy and McDonad, 2015; Mahmoud and Abd El-Kader, 2015; Adamcová et al., 2016). There is a need to develop a program to achieve the sustainability of the soil system as the soils offers goods, services and resources to the humankind (Keesstra et al., 2012; Brevik et al., 2015; Keesstra et al., 2016). The program of systematic monitoring of soil pollution in Belgrade is aimed at testing the concentration of hazardous and harmful substances in soil at urban areas, interpretation of the results in accordance with current legislation, soil characteristics and geology and terrain, proposal of preventive and remedial measures in the wider territory of Belgrade. The paper gives an overview of the results of systematic monitoring of soil pollution in Belgrade in the period from 2009 to 2013. In accordance with the objectives of the investigation during the period from 2009-2013, while having in mind the purpose and manner of land use, the program of monitoring of soil pollution in the territory of Belgrade is oriented to the following areas: 1 - Land in the zone of the sanitary protection of the Belgrade water supply system, 2- Land in zone nearby the main roads, 3 - Land within the communal areas (public areas and agricultural land in the wider vicinity of Belgrade). On the basis of the conducted soil monitoring in the wider area of Belgrade, a large number of sites is contaminated with higher concentrations of hazardous and harmful substances that are exceeding the maximum allowed prescribed legal norms. The causes of soil contamination are both, anthropogenic and natural. Taking into account the all results, the most common deviation is referred to the increased nickel content in soil. A number of soil samples showed increase in concentrations of pollutants including Cu, Zn, Pb, Cd, As, Cr, Hg and organic pollutants. A special surveillance of soil pollution is related to the determination of the contents of hazardous and harmful substances in the soil surrounding public fountains with drinking water. The results indicated an increased content of Pb, Cd, Zn, Cu and pesticide residues that could lead to deterioration of the quality of drinking water of these springs and to endanger the health of the population that use this water. Investigation included determination of the level of radioactive elements in soil such are Cs, Sr and U. The presence of the registered harmful and hazardous substances in the soil on the territory of Belgrade requires continued monitoring the content of these pollutants including an assessment of potential adverse effects on the human health and the environment, as well as undertaking the necessary prevention and protection measures. Acknowledgements. The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 603498 (RECARE project) References Adamcová, D., Vaverková, M.D., Bartoň, S., Havlíček, Z., Břou\\vsková, E. 2016. Soil contamination in landfills: A case study of a landfill in Czech Republic. Solid Earth, 7 (1), pp. 239-247. DOI: http://dx.doi.org/10.5194/se-7-239-2016 Brevik, E. C., Cerdà, A., Mataix-Solera, J., Pereg, L., Quinton, J. N., Six, J., and Van Oost, K. 2015. The interdisciplinary nature of SOIL, SOIL, 1, 117-129, doi:10.5194/soil-1-117-2015, Elkhatib, E., M. Moharem, A. Mahdy, and M. Mesalem. 2016. Sorption, Release and Forms of Mercury in Contaminated Soils Stabilized with Water Treatment Residual Nanoparticles. Land Degradation and Development. doi:10.1002/ldr.2559. Hu, Y. -L, Z. -X Niu, D. -H Zeng, and C. -Y Wang. 2015. Soil Amendment Improves Tree Growth and Soil Carbon and Nitrogen Pools in Mongolian Pine Plantations on Post-Mining Land in Northeast China. Land Degradation and Development 26 (8): 807-812. doi:10.1002/ldr.2386. Keesstra, S. D., Bouma, J., Wallinga, J., Tittonell, P., Smith, P., Cerdà, A., Montanarella, L., Quinton, J. N., Pachepsky, Y., van der Putten, W. H., Bardgett, R. D., Moolenaar, S., Mol, G., Jansen, B., and Fresco, L. O.: The significance of soils and soil science towards realization of the United Nations Sustainable Development Goals, SOIL, 2, 111-128, doi:10.5194/soil-2-111-2016, 2016. Keesstra, S.D., Geissen, V., van Schaik, L., Mosse., K., Piiranen, S., 2012. Soil as a filter for groundwater quality. Current Opinions in Environmental Sustainability 4, 507-516. doi:10.1016/j.cosust.2012.10.007 Mahmoud, E. and N. Abd El-Kader. 2015. Heavy Metal Immobilization in Contaminated Soils using Phosphogypsum and Rice Straw Compost. Land Degradation and Development 26 (8): 819-824. doi:10.1002/ldr.2288. Mao, W., S. Kang, Y. Wan, Y. Sun, X. Li, and Y. Wang. 2016. Yellow River Sediment as a Soil Amendment for Amelioration of Saline Land in the Yellow River Delta. Land Degradation and Development 27 (6): 1595-1602. doi:10.1002/ldr.2323. Roy, M. and L. M. Mcdonald. 2015. Metal Uptake in Plants and Health Risk Assessments in Metal-Contaminated Smelter Soils. Land Degradation and Development 26 (8): 785-792. doi:10.1002/ldr.2237. Trujillo-González, J.M., Torres-Mora, M.A., Keesstra, S., Brevik, E.C., Jiménez-Ballesta, R. 2016. Heavy metal accumulation related to population density in road dust samples taken from urban sites under different land uses. Science of the Total Environment, 553, pp. 636-642. DOI: 10.1016/j.scitotenv.2016.02.101

Wavefront error sensing for LDR

NASA Technical Reports Server (NTRS)

Tubbs, Eldred F.; Glavich, T. A.

1988-01-01

Wavefront sensing is a significant aspect of the LDR control problem and requires attention at an early stage of the control system definition and design. A combination of a Hartmann test for wavefront slope measurement and an interference test for piston errors of the segments was examined and is presented as a point of departure for further discussion. The assumption is made that the wavefront sensor will be used for initial alignment and periodic alignment checks but that it will not be used during scientific observations. The Hartmann test and the interferometric test are briefly examined.

One dimensional two-body collisions experiment based on LabVIEW interface with Arduino

NASA Astrophysics Data System (ADS)

Saphet, Parinya; Tong-on, Anusorn; Thepnurat, Meechai

2017-09-01

The purpose of this work is to build a physics lab apparatus that is modern, low-cost and simple. In one dimensional two-body collisions experiment, we used the Arduino UNO R3 as a data acquisition system which was controlled by LabVIEW program. The photogate sensors were designed using LED and LDR to measure position as a function of the time. Aluminium frame houseware and blower were used for the air track system. In both totally inelastic and elastic collision experiments, the results of momentum and energy conservation are in good agreement with the theoretical calculations.

Testing lagoonal sediments with early life stages of the copepod Acartia tonsa (Dana): An approach to assess sediment toxicity in the Venice Lagoon.

PubMed

Picone, Marco; Bergamin, Martina; Delaney, Eugenia; Ghirardini, Annamaria Volpi; Kusk, Kresten Ole

2018-01-01

The early-life stages of development of the calanoid copepod Acartia tonsa from egg to copepodite I is proposed as an endpoint for assessing sediment toxicity by exposing newly released eggs directly onto the sediment-water interface. A preliminary study of 5 sediment samples collected in the lagoon of Venice highlighted that the larval development rate (LDR) and the early-life stages (ELS) mortality endpoints with A. tonsa are more sensitive than the standard amphipod mortality test; moreover LDR resulted in a more reliable endpoint than ELS mortality, due to the interference of the sediment with the recovery of unhatched eggs and dead larvae. The LDR data collected in a definitive study of 48 sediment samples from the Venice Lagoon has been analysed together with the preliminary data to evaluate the statistical performances of the bioassay (among replicate variance and minimum significant difference between samples and control) and to investigate the possible correlation with sediment chemistry and physical properties. The results showed that statistical performances of the LDR test with A. tonsa correspond with the outcomes of other tests applied to the sediment-water interface (Strongylocentrotus purpuratus embryotoxicity test), sediments (Neanthes arenaceodentata survival and growth test) and porewater (S. purpuratus); the LDR endpoint did, however, show a slightly higher variance as compared with other tests used in the Lagoon of Venice, such as 10-d amphipod lethality test and larval development with sea urchin and bivalves embryos. Sediment toxicity data highlighted the high sensitivity and the clear ability of the larval development to discriminate among sediments characterized by different levels of contamination. The data of the definitive study evidenced that inhibition of the larval development was not affected by grain-size and the organic carbon content of the sediment; in contrast, a strong correlation between inhibition of the larval development and the sediment concentrations of some metals (Cu, Hg, Pb, Zn), acid-volatile sulphides (AVS), polychlorinated biphenyls (PCBs) and polynuclear aromatic hydrocarbons (PAHs) was found. No correlation was found with DDTs, hexachlorobenzene and organotin compounds. Copyright © 2017 Elsevier Inc. All rights reserved.

Spectroscopic characterization of low dose rate brachytherapy sources

NASA Astrophysics Data System (ADS)

Beach, Stephen M.

The low dose rate (LDR) brachytherapy seeds employed in permanent radioactive-source implant treatments usually use one of two radionuclides, 125I or 103Pd. The theoretically expected source spectroscopic output from these sources can be obtained via Monte Carlo calculation based upon seed dimensions and materials as well as the bare-source photon emissions for that specific radionuclide. However the discrepancies resulting from inconsistent manufacturing of sources in comparison to each other within model groups and simplified Monte Carlo calculational geometries ultimately result in undesirably large uncertainties in the Monte Carlo calculated values. This dissertation describes experimentally attained spectroscopic outputs of the clinically used brachytherapy sources in air and in liquid water. Such knowledge can then be applied to characterize these sources by a more fundamental and metro logically-pure classification, that of energy-based dosimetry. The spectroscopic results contained within this dissertation can be utilized in the verification and benchmarking of Monte Carlo calculational models of these brachytherapy sources. This body of work was undertaken to establish a usable spectroscopy system and analysis methods for the meaningful study of LDR brachytherapy seeds. The development of a correction algorithm and the analysis of the resultant spectroscopic measurements are presented. The characterization of the spectrometer and the subsequent deconvolution of the measured spectrum to obtain the true spectrum free of any perturbations caused by the spectrometer itself is an important contribution of this work. The approach of spectroscopic deconvolution that was applied in this work is derived in detail and it is applied to the physical measurements. In addition, the spectroscopically based analogs to the LDR dosimetry parameters that are currently employed are detailed, as well as the development of the theory and measurement methods to arrive at these analogs. Several dosimetrically-relevant water-equivalent plastics were also investigated for their transmission properties within a liquid water environment, as well as in air. The framework for the accurate spectrometry of LDR sources is established as a result of this dissertation work. In addition to the measurement and analysis methods, this work presents the basic measured spectroscopic characteristics of each LDR seed currently in use in the clinic today.

Automatic Lamp and Fan Control Based on Microcontroller

NASA Astrophysics Data System (ADS)

Widyaningrum, V. T.; Pramudita, Y. D.

2018-01-01

In general, automation can be described as a process following pre-determined sequential steps with a little or without any human exertion. Automation is provided with the use of various sensors suitable to observe the production processes, actuators and different techniques and devices. In this research, the automation system developed is an automatic lamp and an automatic fan on the smart home. Both of these systems will be processed using an Arduino Mega 2560 microcontroller. A microcontroller is used to obtain values of physical conditions through sensors connected to it. In the automatic lamp system required sensors to detect the light of the LDR (Light Dependent Resistor) sensor. While the automatic fan system required sensors to detect the temperature of the DHT11 sensor. In tests that have been done lamps and fans can work properly. The lamp can turn on automatically when the light begins to darken, and the lamp can also turn off automatically when the light begins to bright again. In addition, it can concluded also that the readings of LDR sensors are placed outside the room is different from the readings of LDR sensors placed in the room. This is because the light intensity received by the existing LDR sensor in the room is blocked by the wall of the house or by other objects. Then for the fan, it can also turn on automatically when the temperature is greater than 25°C, and the fan speed can also be adjusted. The fan may also turn off automatically when the temperature is less than equal to 25°C.

Brachytherapy for Buccal Cancer: From Conventional Low Dose Rate (LDR) or Mold Technique to High Dose Rate Interstitial Brachytherapy (HDR-ISBT).

PubMed

Kotsuma, Tadayuki; Yamazaki, Hideya; Masui, Koji; Yoshida, Ken; Shimizutani, Kimishige; Akiyama, Hironori; Murakami, Shumei; Isohashi, Fumiaki; Yoshioka, Yasuo; Ogawa, Kazuhiko; Tanaka, Eiichi

2017-12-01

To examine the effectiveness of newly-installed high-dose-rate interstitial brachytherapy (HDR-ISBT) for buccal cancer. We retrospectively reviewed 36 patients (25 men and 11 women) with buccal cancer treated with curative brachytherapy with or without external radiotherapy with a median follow-up of 99 months. A total of 15 HDR-ISBT (median 48 Gy/ 8 fractions, range=24-60 Gy) patients were compared to conventional 15 cases LDR-ISBT (70 Gy, range=42.8-110 Gy) and 7 molds techniques (15 Gy, range=9-74 Gy). A total of 31 patients also underwent external radiotherapy (30 Gy, range=24-48 Gy). They comprised of 3T1, 23 T2, 8 T3, 3 T4 including 11 node positive cases. HDR-ISBT provided 82% of local control rate at 5 years, whereas conventional brachytherapy showed 72% [p=0.44; LDR-ISBT (65%), mold therapy (85.7%)]. Patients with early lesions (T1-2 or stage I-II) showed better local control rates than those with advanced lesions (T3-4 or stage III-IV). Severe late grade 3 complications developed in two patients treated with LDR-ISBT and EBRT. There is no significant difference in toxicity grade ≤2 between conventional brachytherapy (5/15=33%) and HDR-ISBT (7/32=32%, p=0.92). HDR-ISBT achieved good and comparable local control rates to conventional brachytherapy without elevating the toxicity. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Optical Modeling of Sea Salt Aerosols: The Effects of Nonsphericity and Inhomogeneity

NASA Astrophysics Data System (ADS)

Bi, Lei; Lin, Wushao; Wang, Zheng; Tang, Xiaoyun; Zhang, Xiaoyu; Yi, Bingqi

2018-01-01

The nonsphericity and inhomogeneity of marine aerosols (sea salts) have not been addressed in pertinent radiative transfer calculations and remote sensing studies. This study investigates the optical properties of nonspherical and inhomogeneous sea salts using invariant imbedding T-matrix simulations. Dry sea salt aerosols are modeled based on superellipsoidal geometries with a prescribed aspect ratio and roundness parameter. Wet sea salt particles are modeled as coated superellipsoids, as spherical particles with a superellipsoidal core, and as homogeneous spheres depending on the level of relative humidity. Aspect ratio and roundness parameters are found to be critical to interpreting the linear depolarization ratios (LDRs) of NaCl crystals from laboratory measurements. The optimal morphology parameters of NaCl necessary to reproduce the measurements are found to be consistent with data gleaned from an electron micrograph. The LDRs of wet sea salts are computed based on inhomogeneous models and compared with the measured data from ground-based LiDAR. The dependence of the LDR on relative humidity is explicitly considered. The increase in the LDR with relative humidity at the initial phase of deliquescence is attributed to both the size increase and the inhomogeneity effect. For large humidity values, the LDR substantially decreases because the overall particle shape becomes more spherical and the inhomogeneity effect in a particle on the LDR is suppressed for submicron sea salts. However, the effect of inhomogeneity on optical properties is pronounced for coarse-mode sea salts. These findings have important implications for atmospheric radiative transfer and remote sensing involving sea salt aerosols.

Preliminary results from multiparameter airborne rain radar measurement in the western Pacific

NASA Technical Reports Server (NTRS)

Kumagai, Hiroshi; Meneghini, Robert; Kozu, Toshiaki

1993-01-01

Preliminary results are presented from multiparameter airborne radar measurements of tropical storms. The experiment was conducted in the western Pacific in September 1990 with the NASA DC-8 aircraft that was equipped with a dual-wavelength radar at X and Ka bands and several microwave radiometers. The modification to dual-polarization at X-band radar enabled measurements of the linear depolarization ratio (LDR). Vertical profiles of dual-polarization and dual-frequency observables for an example of stratiform rain and three examples of convective rain cells are examined. It is shown that at nadir incidence the LDR measurement often can be used to distinguish the phase states of the hydrometeors and to identify the melting layer. In addition to the information concerning particle shape and orientation from LDR, the ratio of the radar reflectivity factors in two frequency bands (X and Ka bands) provides insight into particle size. The capabilities of dual-wavelength and dual-polarization radar in the identification of particle size and phase will be important considerations in the design of future spaceborne weather radars.

The Liquid Droplet Radiator - an Ultralightweight Heat Rejection System for Efficient Energy Conversion in Space

NASA Technical Reports Server (NTRS)

Mattick, A. T.; Hertzberg, A.

1984-01-01

A heat rejection system for space is described which uses a recirculating free stream of liquid droplets in place of a solid surface to radiate waste heat. By using sufficiently small droplets ( 100 micron diameter) of low vapor pressure liquids the radiating droplet sheet can be made many times lighter than the lightest solid surface radiators (heat pipes). The liquid droplet radiator (LDR) is less vulnerable to damage by micrometeoroids than solid surface radiators, and may be transported into space far more efficiently. Analyses are presented of LDR applications in thermal and photovoltaic energy conversion which indicate that fluid handling components (droplet generator, droplet collector, heat exchanger, and pump) may comprise most of the radiator system mass. Even the unoptimized models employed yield LDR system masses less than heat pipe radiator system masses, and significant improvement is expected using design approaches that incorporate fluid handling components more efficiently. Technical problems (e.g., spacecraft contamination and electrostatic deflection of droplets) unique to this method of heat rejectioon are discussed and solutions are suggested.

The liquid droplet radiator - An ultralightweight heat rejection system for efficient energy conversion in space

NASA Technical Reports Server (NTRS)

Mattick, A. T.; Hertzberg, A.

1981-01-01

A heat rejection system for space is described which uses a recirculating free stream of liquid droplets in place of a solid surface to radiate waste heat. By using sufficiently small droplets (less than about 100 micron diameter) of low vapor pressure liquids (tin, tin-lead-bismuth eutectics, vacuum oils) the radiating droplet sheet can be made many times lighter than the lightest solid surface radiators (heat pipes). The liquid droplet radiator (LDR) is less vulnerable to damage by micrometeoroids than solid surface radiators, and may be transported into space far more efficiently. Analyses are presented of LDR applications in thermal and photovoltaic energy conversion which indicate that fluid handling components (droplet generator, droplet collector, heat exchanger, and pump) may comprise most of the radiator system mass. Even the unoptimized models employed yield LDR system masses less than heat pipe radiator system masses, and significant improvement is expected using design approaches that incorporate fluid handling components more efficiently. Technical problems (e.g., spacecraft contamination and electrostatic deflection of droplets) unique to this method of heat rejection are discussed and solutions are suggested.

Detection of extrasolar planets by the large deployable reflector

NASA Technical Reports Server (NTRS)

Hollenbach, D. J.; Takahashi, T.

1984-01-01

The best wavelength for observing Jupiter-size planetary companions to stars other than the Sun is one at which a planet's thermal emission is strongest; typically this would occur in the far-infrared region. It is assumed that the orbiting infrared telescope used is diffraction-limited so that the resolution of the planet from the central star is accomplished in the wings of the star's Airy pattern. Proxima Centauri, Barnard's Star, Wolf 359, and Epsilon Eridani are just a few of the many nearest main-sequence stars that could be studied with the large deployable relfector (LDR). The detectability of a planet improves for warmer planets and less luminous stars; therefore, planets around white dwarfs and those young planets which have sufficient internal gravitational energy release so as to cause a significant increase in their temperatures are considered. If white dwarfs are as old as they are usually assumed to be (5-10 billion yr), then only the nearest white dwarf (Sirius B) is within the range of LDR. The Ursa Major cluster and Perseu cluster are within LDR's detection range mainly because of their proximity and young age, respectively.

Forward and backward tone mapping of high dynamic range images based on subband architecture

NASA Astrophysics Data System (ADS)

Bouzidi, Ines; Ouled Zaid, Azza

2015-01-01

This paper presents a novel High Dynamic Range (HDR) tone mapping (TM) system based on sub-band architecture. Standard wavelet filters of Daubechies, Symlets, Coiflets and Biorthogonal were used to estimate the proposed system performance in terms of Low Dynamic Range (LDR) image quality and reconstructed HDR image fidelity. During TM stage, the HDR image is firstly decomposed in sub-bands using symmetrical analysis-synthesis filter bank. The transform coefficients are then rescaled using a predefined gain map. The inverse Tone Mapping (iTM) stage is straightforward. Indeed, the LDR image passes through the same sub-band architecture. But, instead of reducing the dynamic range, the LDR content is boosted to an HDR representation. Moreover, in our TM sheme, we included an optimization module to select the gain map components that minimize the reconstruction error, and consequently resulting in high fidelity HDR content. Comparisons with recent state-of-the-art methods have shown that our method provides better results in terms of visual quality and HDR reconstruction fidelity using objective and subjective evaluations.

Robust linear discriminant analysis with distance based estimators

NASA Astrophysics Data System (ADS)

Lim, Yai-Fung; Yahaya, Sharipah Soaad Syed; Ali, Hazlina

2017-11-01

Linear discriminant analysis (LDA) is one of the supervised classification techniques concerning relationship between a categorical variable and a set of continuous variables. The main objective of LDA is to create a function to distinguish between populations and allocating future observations to previously defined populations. Under the assumptions of normality and homoscedasticity, the LDA yields optimal linear discriminant rule (LDR) between two or more groups. However, the optimality of LDA highly relies on the sample mean and pooled sample covariance matrix which are known to be sensitive to outliers. To alleviate these conflicts, a new robust LDA using distance based estimators known as minimum variance vector (MVV) has been proposed in this study. The MVV estimators were used to substitute the classical sample mean and classical sample covariance to form a robust linear discriminant rule (RLDR). Simulation and real data study were conducted to examine on the performance of the proposed RLDR measured in terms of misclassification error rates. The computational result showed that the proposed RLDR is better than the classical LDR and was comparable with the existing robust LDR.

High dynamic range coding imaging system

NASA Astrophysics Data System (ADS)

Wu, Renfan; Huang, Yifan; Hou, Guangqi

2014-10-01

We present a high dynamic range (HDR) imaging system design scheme based on coded aperture technique. This scheme can help us obtain HDR images which have extended depth of field. We adopt Sparse coding algorithm to design coded patterns. Then we utilize the sensor unit to acquire coded images under different exposure settings. With the guide of the multiple exposure parameters, a series of low dynamic range (LDR) coded images are reconstructed. We use some existing algorithms to fuse and display a HDR image by those LDR images. We build an optical simulation model and get some simulation images to verify the novel system.

Wavefront error sensing

NASA Technical Reports Server (NTRS)

Tubbs, Eldred F.

1986-01-01

A two-step approach to wavefront sensing for the Large Deployable Reflector (LDR) was examined as part of an effort to define wavefront-sensing requirements and to determine particular areas for more detailed study. A Hartmann test for coarse alignment, particularly segment tilt, seems feasible if LDR can operate at 5 microns or less. The direct measurement of the point spread function in the diffraction limited region may be a way to determine piston error, but this can only be answered by a detailed software model of the optical system. The question of suitable astronomical sources for either test must also be addressed.

State-of-the-art: prostate LDR brachytherapy.

PubMed

Voulgaris, S; Nobes, J P; Laing, R W; Langley, S E M

2008-01-01

This article on low dose rate (LDR) prostate brachytherapy reviews long-term results, patient selection and quality of life issues. Mature results from the United States and United Kingdom are reported and issues regarding definitions of biochemical failure are discussed. Latest data comparing brachytherapy with radical prostatectomy or no definitive treatment and also the risk of secondary malignancies after prostate brachytherapy are presented. Urological parameters of patient selection and quality of life issues concerning urinary, sexual and bowel function are reviewed. The position of prostate brachytherapy next to surgery as a first-line treatment modality is demonstrated.

Composite panel development at JPL

NASA Technical Reports Server (NTRS)

Mcelroy, Paul; Helms, Rich

1988-01-01

Parametric computer studies can be use in a cost effective manner to determine optimized composite mirror panel designs. An InterDisciplinary computer Model (IDM) was created to aid in the development of high precision reflector panels for LDR. The materials properties, thermal responses, structural geometries, and radio/optical precision are synergistically analyzed for specific panel designs. Promising panels designs are fabricated and tested so that comparison with panel test results can be used to verify performance prediction models and accommodate design refinement. The iterative approach of computer design and model refinement with performance testing and materials optimization has shown good results for LDR panels.

The location discrimination reversal task in mice is sensitive to deficits in performance caused by aging, pharmacological and other challenges.

PubMed

Graf, Radka; Longo, Jami L; Hughes, Zoë A

2018-06-01

Deficits in hippocampal-mediated pattern separation are one aspect of cognitive function affected in schizophrenia (SZ) or Alzheimer's disease (AD). To develop novel therapies, it is beneficial to explore this specific aspect of cognition preclinically. The location discrimination reversal (LDR) task is a hippocampal-dependent operant paradigm that evaluates spatial learning and cognitive flexibility using touchscreens. Here we assessed baseline performance as well as multimodal disease-relevant manipulations in mice. Mice were trained to discriminate between the locations of two images where the degree of separation impacted performance. Administration of putative pro-cognitive agents was unable to improve performance at narrow separation. Furthermore, a range of disease-relevant manipulations were characterized to assess whether performance could be impaired and restored. Pertinent to the cholinergic loss in AD, scopolamine (0.1 mg/kg) produced a disruption in LDR, which was attenuated by donepezil (1 mg/kg). Consistent with NMDA hypofunction in cognitive impairment associated with SZ, MK-801 (0.1 mg/kg) also disrupted performance; however, this deficit was not modified by rolipram. Microdeletion of genes associated with SZ (22q11) resulted in impaired performance, which was restored by rolipram (0.032 mg/kg). Since aging and inflammation affect cognition and are risk factors for AD, these aspects were also evaluated. Aged mice were slower to acquire the task than young mice and did not reach the same level of performance. A systemic inflammatory challenge (lipopolysaccharide (LPS), 1 mg/kg) produced prolonged (7 days) deficits in the LDR task. These data suggest that LDR task is a valuable platform for evaluating disease-relevant deficits in pattern separation and offers potential for identifying novel therapies.

Using Satellites to Investigate the Sensitivity of Longwave Downward Radiation to Water Vapor at High Elevations

NASA Technical Reports Server (NTRS)

Naud, Catherine M.; Miller, James R.; Landry, Chris

2012-01-01

Many studies suggest that high-elevation regions may be among the most sensitive to future climate change. However, in situ observations in these often remote locations are too sparse to determine the feedbacks responsible for enhanced warming rates. One of these feedbacks is associated with the sensitivity of longwave downward radiation (LDR) to changes in water vapor, with the sensitivity being particularly large in many high-elevation regions where the average water vapor is often low. We show that satellite retrievals from the Moderate Resolution Imaging Spectroradiometer (MODIS) and Clouds and the Earth's Radiant Energy System (CERES) can be used to expand the current ground-based observational database and that the monthly averaged clear-sky satellite estimates of humidity and LDR are in good agreement with the well-instrumented Center for Snow and Avalanche Studies ground-based site in the southwestern Colorado Rocky Mountains. The relationship between MODIS-retrieved precipitable water vapor and surface specific humidity across the contiguous United States was found to be similar to that previously found for the Alps. More important, we show that satellites capture the nonlinear relationship between LDR and water vapor and confirm that LDR is especially sensitive to changes in water vapor at high elevations in several midlatitude mountain ranges. Because the global population depends on adequate fresh water, much of which has its source in high mountains, it is critically important to understand how climate will change there. We demonstrate that satellites can be used to investigate these feedbacks in high-elevation regions where the coverage of surface-based observations is insufficient to do so.

Larval development ratio test with the calanoid copepod Acartia tonsa as a new bioassay to assess marine sediment quality.

PubMed

Buttino, Isabella; Vitiello, Valentina; Macchia, Simona; Scuderi, Alice; Pellegrini, David

2018-03-01

The copepod Acartia tonsa was used as a model species to assess marine sediment quality. Acute and chronic bioassays, such as larval development ratio (LDR) and different end-points were evaluated. As a pelagic species, A. tonsa is mainly exposed to water-soluble toxicants and bioassays are commonly performed in seawater. However, an interaction among A. tonsa eggs and the first larval stages with marine sediments might occur in shallow water environments. Here we tested two different LDR protocols by incubating A. tonsa eggs in elutriates and sediments coming from two areas located in Tuscany Region (Central Italy): Livorno harbour and Viareggio coast. The end-points analyzed were larval mortality (LM) and development inhibition (DI) expressed as the percentage of copepods that completed the metamorphosis from nauplius to copepodite. Aims of this study were: i) to verify the suitability of A. tonsa copepod for the bioassay with sediment and ii) to compare the sensitivity of A. tonsa exposed to different matrices, such as water and sediment. A preliminary acute test was also performed. Acute tests showed the highest toxicity of Livorno's samples (two out of three) compared to Viareggio samples, for which no effect was observed. On the contrary, LDR tests with sediments and elutriates revealed some toxic effects also for Viareggio's samples. Results were discussed with regards to the chemical characterization of the samples. Our results indicated that different end-points were affected in A. tonsa, depending on the matrices to which the copepods were exposed and on the test used. Bioassays with elutriates and sediments are suggested and LDR test could help decision-makers to identify a more appropriate management of dredging materials. Copyright © 2017 Elsevier Inc. All rights reserved.

Universal ligation-detection-reaction microarray applied for compost microbes

PubMed Central

Hultman, Jenni; Ritari, Jarmo; Romantschuk, Martin; Paulin, Lars; Auvinen, Petri

2008-01-01

Background Composting is one of the methods utilised in recycling organic communal waste. The composting process is dependent on aerobic microbial activity and proceeds through a succession of different phases each dominated by certain microorganisms. In this study, a ligation-detection-reaction (LDR) based microarray method was adapted for species-level detection of compost microbes characteristic of each stage of the composting process. LDR utilises the specificity of the ligase enzyme to covalently join two adjacently hybridised probes. A zip-oligo is attached to the 3'-end of one probe and fluorescent label to the 5'-end of the other probe. Upon ligation, the probes are combined in the same molecule and can be detected in a specific location on a universal microarray with complementary zip-oligos enabling equivalent hybridisation conditions for all probes. The method was applied to samples from Nordic composting facilities after testing and optimisation with fungal pure cultures and environmental clones. Results Probes targeted for fungi were able to detect 0.1 fmol of target ribosomal PCR product in an artificial reaction mixture containing 100 ng competing fungal ribosomal internal transcribed spacer (ITS) area or herring sperm DNA. The detection level was therefore approximately 0.04% of total DNA. Clone libraries were constructed from eight compost samples. The LDR microarray results were in concordance with the clone library sequencing results. In addition a control probe was used to monitor the per-spot hybridisation efficiency on the array. Conclusion This study demonstrates that the LDR microarray method is capable of sensitive and accurate species-level detection from a complex microbial community. The method can detect key species from compost samples, making it a basis for a tool for compost process monitoring in industrial facilities. PMID:19116002

A tool based on Ligation Detection Reaction-Universal Array (LDR-UA) for the characterization of VTEC by identification of virulence-associated and serogroup-specific genes.

PubMed

Lauri, Andrea; Castiglioni, Bianca; Morabito, Stefano; Tozzoli, Rosangela; Consolandi, Clarissa; Mariani, Paola

2011-02-01

Verocytoxigenic Escherichia coli (VTEC) are zoonotic pathogens whose natural reservoir is represented by ruminants, particularly cattle. Infections are mainly acquired by consumption of undercooked contaminated food of animal origin, contact with infected animals and contaminated environment. VTEC O157 is the most frequently isolated serogroup from cases of human disease, however, other VTEC serogroups, such as O26, O111, O145 and O103, are increasingly reported as causing Hemolytic Uremic Syndrome (HUS) worldwide. The identification of VTEC is troublesome, hindering the development of effective prevention strategies. In fact, VTEC are morphologically indistinguishable from harmless E. coli and their pathogenic potential is not strictly dependent on the serogroup, but relies on the presence of a collection of virulence genes. We developed a diagnostic tool for VTEC based on the Ligation Detection Reaction coupled to Universal Array (LDR-UA) for the simultaneous identification of virulence factors and serogroup-associated genes. The method includes the investigation of 40 sites located in 13 fragments from 12 genes (sodCF1/F2, adfO, terB, ehxA, eae, vtx1, vtx2, ihp1, wzx, wbdI, rfbE, dnaK) and was evaluated by performing a trial on a collection of 67 E. coli strains, both VTEC and VT-negative E. coli, as well as on 25 isolates belonging to other related species. Results of this study showed that the LDR-UA technique was specific in identifying the target microorganism. Moreover, due to its higher throughput, the LDR-UA can be a valid and cheaper alternative to real time PCR-based (rt-PCR) methods for VTEC identification. Copyright © 2010 Elsevier Ltd. All rights reserved.

HDR and LDR Brachytherapy in the Treatment of Lip Cancer: the Experience of the Catalan Institute of Oncology.

PubMed

Ayerra, Arrate Querejeta; Mena, Estefanía Palacios; Fabregas, Joan Pera; Miguelez, Cristina Gutiérrez; Guedea, Ferran

2010-03-01

Lip cancer can be treated by surgery, external radiotherapy, and/or brachytherapy (BT). In recent years, BT has become increasingly favored for this type of cancer. The aim of the present study was to analyze local control and survival of patients treated at our institution between July 1989 and June 2008. We performed a retrospective study of 121 patients (109 males and 12 females) who underwent lip cancer brachytherapy from July 1989 to June 2008. Median age was 67 years and median follow-up was 31.8 months (range 20-188 months). Out of 121 patients, 100 (82.6%) were treated with low dose rate (LDR) BT while the remaining 21 patients (17.4%) received high dose rate (HDR) BT. The most common cell type was squamous cell carcinoma (115 cases; 95%) and most tumors were located on the lower lip (107 patients; 88.4%). Most cases were either stage T1 (62 patients; 51.2%), or T2 (44 cases; 36.4%). After 15 years of follow-up, overall survival was 89.5%, cause-specific survival 97.8%, and disease-free survival 86.6%. Local, regional, and distant control at 15 years were 90%, 92%, and 98.8%, respectively. Grade 3 mucosal toxicity was observed in 23% of patients treated with LDR compared to 33% of HDR patients, and grade 4 mucosal toxicity in 9% versus 0% in the HDR group. Our findings confirm that brachytherapy is an effective treatment for lip cancer. The results from our series are in line with those published elsewhere. Based on our limited data, HDR appears to be equally as good as LDR, although this needs to be confirmed by further studies.

Leucine disposal rate for assessment of amino acid metabolism in maintenance hemodialysis patients

PubMed Central

Denny, Gerald B.; Deger, Serpil M.; Chen, Guanhua; Bian, Aihua; Sha, Feng; Booker, Cindy; Kesler, Jaclyn T.; David, Sthuthi; Ellis, Charles D.; Ikizler, T. Alp

2016-01-01

Background Protein energy wasting (PEW) is common in patients undergoing maintenance hemodialysis (MHD) and closely associated with poor outcomes. Insulin resistance and associated alterations in amino acid metabolism are potential pathways leading to PEW. We hypothesized that the measurement of leucine disposal during a hyperinsulinemic- euglycemic-euaminoacidemic clamp (HEAC) procedure would accurately measure the sensitivity to insulin for its actions on concomitant carbohydrate and protein metabolism in MHD patients. Methods We examined 35 MHD patients and 17 control subjects with normal kidney function by hyperinsulinemic-euglycemic clamp (HEGC) followed by HEAC clamp procedure to obtain leucine disposal rate (LDR) along with isotope tracer methodology to assess whole body protein turnover. Results The glucose disposal rate (GDR) by HEGC was 5.1 ± 2.1 mg/kg/min for the MHD patients compared to 6.3 ± 3.9 mg/kg/min for the controls (p = 0.38). The LDR during HEAC was 0.09 ± 0.03 mg/kg/min for the MHD patients compared to 0.11 ± 0.05 mg/kg/min for the controls (p = 0.009). The LDR level was correlated with whole body protein synthesis (r = 0.25; p = 0.08), with whole body protein breakdown (r = −0.38 p = 0.01) and net protein balance (r = 0.85; p < 0.001) in the overall study population. Correlations remained significant in subgroup analysis. The GDR derived by HEGC and LDR correlated well in the controls (r = 0.79, p < 0.001), but less so in the MHD patients (r = 0.58, p < 0.001). Conclusions Leucine disposal rate reliably measures amino acid utilization in MHD patients and controls in response to high dose insulin. PMID:27413537

High versus low-dose rate brachytherapy for cervical cancer.

PubMed

Patankar, Sonali S; Tergas, Ana I; Deutsch, Israel; Burke, William M; Hou, June Y; Ananth, Cande V; Huang, Yongmei; Neugut, Alfred I; Hershman, Dawn L; Wright, Jason D

2015-03-01

Brachytherapy plays an important role in the treatment of cervical cancer. While small trials have shown comparable survival outcomes between high (HDR) and low-dose rate (LDR) brachytherapy, little data is available in the US. We examined the utilization of HDR brachytherapy and analyzed the impact of type of brachytherapy on survival for cervical cancer. Women with stages IB2-IVA cervical cancer treated with primary (external beam and brachytherapy) radiotherapy between 2003-2011 and recorded in the National Cancer Database (NCDB) were analyzed. Generalized linear mixed models and Cox proportional hazards regression were used to examine predictors of HDR brachytherapy use and the association between HDR use and survival. A total of 10,564 women including 2681 (25.4%) who received LDR and 7883 (74.6%) that received HDR were identified. Use of HDR increased from 50.2% in 2003 to 83.9% in 2011 (P<0.0001). In a multivariable model, year of diagnosis was the strongest predictor of use of HDR. While patients in the Northeast were more likely to receive HDR therapy, there were no other clinical or socioeconomic characteristics associated with receipt of HDR. In a multivariable Cox model, survival was similar between the HDR and LDR groups (HR=0.93; 95% CI 0.83-1.03). Similar findings were noted in analyses stratified by stage and histology. Kaplan-Meier analyses demonstrated no difference in survival based on type of brachytherapy for stage IIB (P=0.68), IIIB (P=0.17), or IVA (P=0.16) tumors. The use of HDR therapy has increased rapidly. Overall survival is similar for LDR and HDR brachytherapy. Copyright © 2015 Elsevier Inc. All rights reserved.

New phase method of measuring particle size with laser Doppler radar

NASA Astrophysics Data System (ADS)

Zemlianskii, Vladimir M.

1996-06-01

A vast field of non-contact metrology, vibrometry, dynamics and microdynamics problems solved on the basis of laser Doppler method resulted in the development of great variety of laser Doppler radar (LDR). In coherent LDR few beams with various polarization are generally adopted, that are directed at the zone of measurement, through which the probing air stream moves. Studies of various coherent LDR demonstrated that polarization-phase effects of scattering can in some cases considerably effect on the signal-to-noise ratio of the Doppler signal. On the other side using phase effects can simultaneous measurement of size and velocity of spherical particles. New possibilities for improving the accuracy of measuring spherical particles' sizes come to light when application is made in coherent LDR of two waves- probing and one out of the types of symmetrical reception of scattered radiation, during which phase-conjugate signals are formed. The theoretical analysis on the basis of the scattering theory showed, that in symmetrical reception of scattered radiation with respect to the planes OXZ and OYZ output signal of the photoreceiver contains two high- frequency signal components, which in relation to parameters of the probing and size, can either be in phase or antiphase. Results of numerical modeling are presented: amplitude of high frequency signal, coefficient of phase and polarization matching of mixed waves, the depths of photocurrent modulation and also signal's phase in relation to the angle between the probing beams. Phase method of determining particle's sizes based on the use of two wavelengths probing and symmetrical reception of scattered radiation in which conditions for the formation of phase conjugated high-frequency signals are satisfied is presented.

Leucine disposal rate for assessment of amino acid metabolism in maintenance hemodialysis patients.

PubMed

Denny, Gerald B; Deger, Serpil M; Chen, Guanhua; Bian, Aihua; Sha, Feng; Booker, Cindy; Kesler, Jaclyn T; David, Sthuthi; Ellis, Charles D; Ikizler, T Alp

Protein energy wasting (PEW) is common in patients undergoing maintenance hemodialysis (MHD) and closely associated with poor outcomes. Insulin resistance and associated alterations in amino acid metabolism are potential pathways leading to PEW. We hypothesized that the measurement of leucine disposal during a hyperinsulinemic- euglycemic-euaminoacidemic clamp (HEAC) procedure would accurately measure the sensitivity to insulin for its actions on concomitant carbohydrate and protein metabolism in MHD patients. We examined 35 MHD patients and 17 control subjects with normal kidney function by hyperinsulinemic-euglycemic clamp (HEGC) followed by HEAC clamp procedure to obtain leucine disposal rate (LDR) along with isotope tracer methodology to assess whole body protein turnover. The glucose disposal rate (GDR) by HEGC was 5.1 ± 2.1 mg/kg/min for the MHD patients compared to 6.3 ± 3.9 mg/kg/min for the controls ( p = 0.38). The LDR during HEAC was 0.09 ± 0.03 mg/kg/min for the MHD patients compared to 0.11 ± 0.05 mg/kg/min for the controls ( p = 0.009). The LDR level was correlated with whole body protein synthesis ( r = 0.25; p = 0.08), with whole body protein breakdown ( r = -0.38 p = 0.01) and net protein balance ( r = 0.85; p < 0.001) in the overall study population. Correlations remained significant in subgroup analysis. The GDR derived by HEGC and LDR correlated well in the controls ( r = 0.79, p < 0.001), but less so in the MHD patients ( r = 0.58, p < 0.001). Leucine disposal rate reliably measures amino acid utilization in MHD patients and controls in response to high dose insulin.

High versus Low-Dose Rate Brachytherapy for Cervical Cancer

PubMed Central

Patankar, Sonali S.; Tergas, Ana I.; Deutsch, Israel; Burke, William M.; Hou, June Y.; Ananth, Cande V.; Huang, Yongmei; Neugut, Alfred I.; Hershman, Dawn L.; Wright, Jason D.

2015-01-01

Objectives Brachytherapy plays an important role in the treatment of cervical cancer. While small trials have shown comparable survival outcomes between high (HDR) and low-dose rate (LDR) brachytherapy, little data is available in the US. We examined the utilization of HDR brachytherapy and analyzed the impact of type of brachytherapy on survival for cervical cancer. Methods Women with stage IB2–IVA cervical cancer treated with primary (external beam and brachytherapy) radiotherapy between 2003–2011 and recorded in the National Cancer Database (NCDB) were analyzed. Generalized linear mixed models and Cox proportional hazards regression were used to examine predictors of HDR brachytherapy use and the association between HDR use and survival. Results A total of 10,564 women including 2681 (25.4%) who received LDR and 7883 (74.6%) that received HDR were identified. Use of HDR increased from 50.2% in 2003 to 83.9% in 2011 (P<0.0001). In a multivariable model, year of diagnosis was the strongest predictor of use of HDR. While patients in the Northeast were more likely to receive HDR therapy, there were no other clinical or socioeconomic characteristics associated with receipt of HDR. In a multivariable Cox model, survival was similar between the HDR and LDR groups (HR=0.93; 95% 0.83–1.03). Similar findings were noted in analyses stratified by stage and histology. Kaplan-Meier analyses demonstrated no difference in survival based on type of brachytherapy for stage IIB (P=0.68), IIIB (P=0.17), or IVA (P=0.16) tumors. Conclusions The use of HDR therapy has increased rapidly. Overall survival is similar for LDR and HDR brachytherapy. PMID:25575481

GGEMS-Brachy: GPU GEant4-based Monte Carlo simulation for brachytherapy applications

NASA Astrophysics Data System (ADS)

Lemaréchal, Yannick; Bert, Julien; Falconnet, Claire; Després, Philippe; Valeri, Antoine; Schick, Ulrike; Pradier, Olivier; Garcia, Marie-Paule; Boussion, Nicolas; Visvikis, Dimitris

2015-07-01

In brachytherapy, plans are routinely calculated using the AAPM TG43 formalism which considers the patient as a simple water object. An accurate modeling of the physical processes considering patient heterogeneity using Monte Carlo simulation (MCS) methods is currently too time-consuming and computationally demanding to be routinely used. In this work we implemented and evaluated an accurate and fast MCS on Graphics Processing Units (GPU) for brachytherapy low dose rate (LDR) applications. A previously proposed Geant4 based MCS framework implemented on GPU (GGEMS) was extended to include a hybrid GPU navigator, allowing navigation within voxelized patient specific images and analytically modeled 125I seeds used in LDR brachytherapy. In addition, dose scoring based on track length estimator including uncertainty calculations was incorporated. The implemented GGEMS-brachy platform was validated using a comparison with Geant4 simulations and reference datasets. Finally, a comparative dosimetry study based on the current clinical standard (TG43) and the proposed platform was performed on twelve prostate cancer patients undergoing LDR brachytherapy. Considering patient 3D CT volumes of 400  × 250  × 65 voxels and an average of 58 implanted seeds, the mean patient dosimetry study run time for a 2% dose uncertainty was 9.35 s (≈500 ms 10-6 simulated particles) and 2.5 s when using one and four GPUs, respectively. The performance of the proposed GGEMS-brachy platform allows envisaging the use of Monte Carlo simulation based dosimetry studies in brachytherapy compatible with clinical practice. Although the proposed platform was evaluated for prostate cancer, it is equally applicable to other LDR brachytherapy clinical applications. Future extensions will allow its application in high dose rate brachytherapy applications.

Dose distribution verification for GYN brachytherapy using EBT Gafchromic film and TG-43 calculation.

PubMed

Gholami, Somayeh; Mirzaei, Hamid Reza; Jabbary Arfaee, Ali; Jaberi, Ramin; Nedaie, Hassan Ali; Rabi Mahdavi, Seied; Rajab Bolookat, Eftekhar; Meigooni, Ali S

2016-01-01

Verification of dose distributions for gynecological (GYN) brachytherapy implants using EBT Gafchromic film. One major challenge in brachytherapy is to verify the accuracy of dose distributions calculated by a treatment planning system. A new phantom was designed and fabricated using 90 slabs of 18 cm × 16 cm × 0.2 cm Perspex to accommodate a tandem and Ovoid assembly, which is normally used for GYN brachytherapy treatment. This phantom design allows the use of EBT Gafchromic films for dosimetric verification of GYN implants with a cobalt-60 HDR system or a LDR Cs-137 system. Gafchromic films were exposed using a plan that was designed to deliver 1.5 Gy of dose to 0.5 cm distance from the lateral surface of ovoids from a pair of ovoid assembly that was used for treatment vaginal cuff. For a quantitative analysis of the results for both LDR and HDR systems, the measured dose values at several points of interests were compared with the calculated data from a commercially available treatment planning system. This planning system was utilizing the TG-43 formalism and parameters for calculation of dose distributions around a brachytherapy implant. The results of these investigations indicated that the differences between the calculated and measured data at different points were ranging from 2.4% to 3.8% for the LDR Cs-137 and HDR Co-60 systems, respectively. The EBT Gafchromic films combined with the newly designed phantom could be utilized for verification of the dose distributions around different GYN implants treated with either LDR or HDR brachytherapy procedures.

IL6-174 G>C Polymorphism (rs1800795) Association with Late Effects of Low Dose Radiation Exposure in the Portuguese Tinea Capitis Cohort

PubMed Central

Mendes, Adélia; Costa, Natália Rios; Chora, Inês; Ferreira, Sara; Araújo, Emanuel; Lopes, Pedro; Rosa, Gilberto; Marques, Pedro; Bettencourt, Paulo; Oliveira, Inês; Costa, Francisco; Ramos, Isabel; Teles, Maria José; Guimarães, João Tiago; Sobrinho-Simões, Manuel; Soares, Paula

2016-01-01

Head and neck cancers, and cardiovascular disease have been described as late effects of low dose radiation (LDR) exposure, namely in tinea capitis cohorts. In addition to radiation dose, gender and younger age at exposure, the genetic background might be involved in the susceptibility to LDR late effects. The -174 G>C (rs1800795) SNP in IL6 has been associated with cancer and cardiovascular disease, nevertheless this association is still controversial. We assessed the association of the IL6-174 G>C SNP with LDR effects such as thyroid carcinoma, basal cell carcinoma and carotid atherosclerosis in the Portuguese tinea capitis cohort. The IL6-174 G>C SNP was genotyped in 1269 individuals formerly irradiated for tinea capitis. This sampling group included thyroid cancer (n = 36), basal cell carcinoma (n = 113) and cases without thyroid or basal cell carcinoma (1120). A subgroup was assessed for atherosclerosis by ultrasonography (n = 379) and included matched controls (n = 222). Genotypes were discriminated by real-time PCR using a TaqMan SNP genotyping assay. In the irradiated group, we observed that the CC genotype was significantly associated with carotid plaque risk, both in the genotypic (OR = 3.57, CI = 1.60–7.95, p-value = 0.002) and in the recessive (OR = 3.02, CI = 1.42–6.42, p-value = 0.004) models. Irradiation alone was not a risk factor for carotid atherosclerosis. We did not find a significant association of the IL6-174 C allele with thyroid carcinoma or basal cell carcinoma risk. The IL6-174 CC genotype confers a three-fold risk for carotid atherosclerotic disease suggesting it may represent a genetic susceptibility factor in the LDR context. PMID:27662210

BrachyView: Combining LDR seed positions with transrectal ultrasound imaging in a prostate gel phantom.

PubMed

Alnaghy, S; Cutajar, D L; Bucci, J A; Enari, K; Safavi-Naeini, M; Favoino, M; Tartaglia, M; Carriero, F; Jakubek, J; Pospisil, S; Lerch, M; Rosenfeld, A B; Petasecca, M

2017-02-01

BrachyView is a novel in-body imaging system which aims to provide LDR brachytherapy seeds position reconstruction within the prostate in real-time. The first prototype is presented in this study: the probe consists of a gamma camera featuring three single cone pinhole collimators embedded in a tungsten tube, above three, high resolution pixelated detectors (Timepix). The prostate was imaged with a TRUS system using a sagittal crystal with a 2.5mm slice thickness. Eleven needles containing a total of thirty 0.508U 125 I seeds were implanted under ultrasound guidance. A CT scan was used to localise the seed positions, as well as provide a reference when performing the image co-registration between the BrachyView coordinate system and the TRUS coordinate system. An in-house visualisation software interface was developed to provide a quantitative 3D reconstructed prostate based on the TRUS images and co-registered with the LDR seeds in situ. A rigid body image registration was performed between the BrachyView and TRUS systems, with the BrachyView and CT-derived source locations compared. The reconstructed seed positions determined by the BrachyView probe showed a maximum discrepancy of 1.78mm, with 75% of the seeds reconstructed within 1mm of their nominal location. An accurate co-registration between the BrachyView and TRUS coordinate system was established. The BrachyView system has shown its ability to reconstruct all implanted LDR seeds within a tissue equivalent prostate gel phantom, providing both anatomical and seed position information in a single interface. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Catch crops impact on soil water infiltration in vineyards

NASA Astrophysics Data System (ADS)

Cerdà, Artemi; Bagarello, Vincenzo; Iovino, Massimo; Ferro, Vito; Keesstra, Saskia; Rodrigo-Comino, Jesús; García Diaz, Andrés; di Prima, Simone

2017-04-01

Infiltration is the key component of the hydrological cycle (Cerdà, 1999; Bagarello et al.,, 2014; Zema et al., 2016). Infiltration determines the partitioning of rainfall into runoff and subsurface flow (Cerdà, 1996; Bagarello et al., 2006; Wang et al., 2016). In the Mediterranean, agriculture resulted in the degradation of the soil structure, reduction of the organic matter and increase in the soil losses (Cerdà et al., 2009; Laudicina et al., 2015; Iovino et al., 2016; Willaarts et al., 2016). There is an urgent need to restore the agriculture soils to avoid floods, reduce the carbon emissions and avoid reservoir siltation (Aksakal et al., 2016; Ben Slimane et al., 2016; Yagüe et al., 2016). Catch Crops are widespread used due to their impact on the soil fertility (Mwango et al., 2016; Nishigaki et al., 2016 ; Nawaz et al., 2016). Catch crops also increase the amount of organic matter but little is known about the effect on soil infiltration. Two paired plots were selected in Les Alcusses (Moixent municipality) in Eastern Iberian Peninsula to compare the infiltration rates between a 8-years catch crop (Vicia sp) with a control (plough) soil. The measurements were carried out by means of ring infiltrometer in August 2014 and December 2014 under dry and wet conditions (Cerdà, 2001; Di Prima et al., 2016). The results show that the steady-state infiltration rates were 1.8 higher during the summer period, and that the catch crops did not increase the infiltration rates. Acknowledgements The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement n 603498 (RECARE project) and the CGL2013- 47862-C2-1-R and CGL2016-75178-C2-2-R national research projects. References Aksakal, E. L., Sari, S., & Angin, I. (2016). Effects of vermicompost application on soil aggregation and certain physical properties. Land Degradation and Development, 27(4), 983-995. doi:10.1002/ldr.2350 Bagarello, V., Castellini, M., Di Prima, S., & Iovino, M. (2014). Soil hydraulic properties determined by infiltration experiments and different heights of water pouring. Geoderma, 213, 492-501. Bagarello, V., Elrick, D. E., Iovino, M., & Sgroi, A. (2006). A laboratory analysis of falling head infiltration procedures for estimating the hydraulic conductivity of soils. Geoderma, 135, 322-334. Ben Slimane, A., Raclot, D., Evrard, O., Sanaa, M., Lefevre, I., & Le Bissonnais, Y. (2016). Relative contribution of Rill/Interrill and Gully/Channel erosion to small reservoir siltation in mediterranean environments. Land Degradation and Development, 27(3), 785-797. doi:10.1002/ldr.2387 Cerdà, A. (1996). Seasonal variability of infiltration rates under contrasting slope conditions in southeast spain. Geoderma, 69(3-4), 217-232. Cerdà, A. (1999). Seasonal and spatial variations in infiltration rates in badland surfaces under mediterranean climatic conditions. Water Resources Research, 35(1), 319-328. doi:10.1029/98WR01659 Cerdà, A. (2001). Effects of rock fragment cover on soil infiltration, interrill runoff and erosion. European Journal of Soil Science, 52(1), 59-68. doi:10.1046/j.1365-2389.2001.00354.x Cerdà, A., Morera, A. G., & Bodí, M. B. (2009). Soil and water losses from new citrus orchards growing on sloped soils in the western mediterranean basin. Earth Surface Processes and Landforms, 34(13), 1822-1830. doi:10.1002/esp.1889 di Prima, S., Lassabatère, L., Bagarello, V., Iovino, M., & Angulo-Jaramillo, R. (2016). Testing a new automated single ring infiltrometer for Beerkan infiltration experiments. Geoderma, 262, 20-34. Iovino, M., Castellini, M., Bagarello, V., & Giordano, G. (2016). Using static and dynamic indicators to evaluate soil physical quality in a sicilian area. Land Degradation and Development, 27(2), 200-210. doi:10.1002/ldr.2263 Laudicina, V. A., Novara, A., Barbera, V., Egli, M., & Badalucco, L. (2015). Long-term tillage and cropping system effects on chemical and biochemical characteristics of soil organic matter in a mediterranean semiarid environment. Land Degradation and Development, 26(1), 45-53. doi:10.1002/ldr.2293 Mamedov, A. I., Bar-Yosef, B., Levkovich, I., Rosenberg, R., Silber, A., Fine, P., & Levy, G. J. (2016). Amending soil with sludge, manure, humic acid, orthophosphate and phytic acid: Effects on infiltration, runoff and sediment loss. Land Degradation and Development, 27(6), 1629-1639. doi:10.1002/ldr.2474 Mwango, S. B., Msanya, B. M., Mtakwa, P. W., Kimaro, D. N., Deckers, J., & Poesen, J. (2016). Effectiveness OF mulching under miraba in controlling soil erosion, fertility restoration and crop yield in the usambara mountains, tanzania. Land Degradation and Development, 27(4), 1266-1275. doi:10.1002/ldr.2332 Nawaz, A., Farooq, M., Lal, R., Rehman, A., Hussain, T., & Nadeem, A. (2016). Influence of sesbania brown manuring and rice residue mulch on soil health, weeds and system productivity of conservation rice-wheat systems. Land Degradation and Development, doi:10.1002/ldr.2578 Nishigaki, T., Shibata, M., Sugihara, S., Mvondo-Ze, A. D., Araki, S., & Funakawa, S. (2016). Effect of mulching with vegetative residues on soil water erosion and water balance in an oxisol cropped by cassava in east cameroon. Land Degradation and Development, doi:10.1002/ldr.2568 Wang, Y., Fan, J., Cao, L., & Liang, Y. (2016). Infiltration and runoff generation under various cropping patterns in the red soil region of china. Land Degradation and Development, 27(1), 83-91. doi:10.1002/ldr.2460 Willaarts, B. A., Oyonarte, C., Muñoz-Rojas, M., Ibáñez, J. J., & Aguilera, P. A. (2016). Environmental factors controlling soil organic carbon stocks in two contrasting mediterranean climatic areas of southern spain. Land Degradation and Development, 27(3), 603-611. doi:10.1002/ldr.2417 Yagüe, M. R., Domingo-Olivé, F., Bosch-Serra, À. D., Poch, R. M., & Boixadera, J. (2016). Dairy cattle manure effects on soil quality: Porosity, earthworms, aggregates and soil organic carbon fractions. Land Degradation and Development, 27(7), 1753-1762. doi:10.1002/ldr.2477 Zema, D. A., Labate, A., Martino, D., & Zimbone, S. M. (2016). Comparing different infiltration methods of the HEC-HMS model: The case study of the mésima torrent (southern italy). Land Degradation and Development, doi:10.1002/ldr.2591

Using LDR as Sensing Element for an External Fuzzy Controller Applied in Photovoltaic Pumping Systems with Variable-Speed Drives.

PubMed

Maranhão, Geraldo Neves De A; Brito, Alaan Ubaiara; Leal, Anderson Marques; Fonseca, Jéssica Kelly Silva; Macêdo, Wilson Negrão

2015-09-22

In the present paper, a fuzzy controller applied to a Variable-Speed Drive (VSD) for use in Photovoltaic Pumping Systems (PVPS) is proposed. The fuzzy logic system (FLS) used is embedded in a microcontroller and corresponds to a proportional-derivative controller. A Light-Dependent Resistor (LDR) is used to measure, approximately, the irradiance incident on the PV array. Experimental tests are executed using an Arduino board. The experimental results show that the fuzzy controller is capable of operating the system continuously throughout the day and controlling the direct current (DC) voltage level in the VSD with a good performance.

PCR/LDR/universal array platforms for the diagnosis of infectious disease.

PubMed

Pingle, Maneesh; Rundell, Mark; Das, Sanchita; Golightly, Linnie M; Barany, Francis

2010-01-01

Infectious diseases account for between 14 and 17 million deaths worldwide each year. Accurate and rapid diagnosis of bacterial, fungal, viral, and parasitic infections is therefore essential to reduce the morbidity and mortality associated with these diseases. Classical microbiological and serological methods have long served as the gold standard for diagnosis but are increasingly being replaced by molecular diagnostic methods that demonstrate increased sensitivity and specificity and provide an identification of the etiologic agent in a shorter period of time. PCR/LDR coupled with universal array detection provides a highly sensitive and specific platform for the detection and identification of bacterial and viral infections.

PCR/LDR/Universal Array Platforms for the Diagnosis of Infectious Disease

PubMed Central

Pingle, Maneesh; Rundell, Mark; Das, Sanchita; Golightly, Linnie M.; Barany, Francis

2015-01-01

Infectious diseases account for between 14 and 17 million deaths worldwide each year. Accurate and rapid diagnosis of bacterial, fungal, viral, and parasitic infections is therefore essential to reduce the morbidity and mortality associated with these diseases. Classical microbiological and serological methods have long served as the gold standard for diagnosis but are increasingly being replaced by molecular diagnostic methods that demonstrate increased sensitivity and specificity and provide an identification of the etiologic agent in a shorter period of time. PCR/LDR coupled with universal array detection provides a highly sensitive and specific platform for the detection and identification of bacterial and viral infections. PMID:20217576

Biological effective dose evaluation in gynaecological brachytherapy: LDR and HDR treatments, dependence on radiobiological parameters, and treatment optimisation.

PubMed

Bianchi, C; Botta, F; Conte, L; Vanoli, P; Cerizza, L

2008-10-01

This study was undertaken to compare the biological efficacy of different high-dose-rate (HDR) and low-dose-rate (LDR) treatments of gynaecological lesions, to identify the causes of possible nonuniformity and to optimise treatment through customised calculation. The study considered 110 patients treated between 2001 and 2006 with external beam radiation therapy and/or brachytherapy with either LDR (afterloader Selectron, (137)Cs) or HDR (afterloader microSelectron Classic, (192)Ir). The treatments were compared in terms of biologically effective dose (BED) to the tumour and to the rectum (linear-quadratic model) by using statistical tests for comparisons between independent samples. The difference between the two treatments was statistically significant in one case only. However, within each technique, we identified considerable nonuniformity in therapeutic efficacy due to differences in fractionation schemes and overall treatment time. To solve this problem, we created a Microsoft Excel spreadsheet allowing calculation of the optimal treatment for each patient: best efficacy (BED(tumour)) without exceeding toxicity threshold (BED(rectum)). The efficacy of a treatment may vary as a result of several factors. Customised radiobiological evaluation is a useful adjunct to clinical evaluation in planning equivalent treatments that satisfy all dosimetric constraints.

Analysis of 35 GHz Cloud Radar polarimetric variables to identify stratiform and convective precipitation.

NASA Astrophysics Data System (ADS)

Fontaine, Emmanuel; Illingworth, Anthony, J.; Stein, Thorwald

2017-04-01

This study is performed using vertical profiles of radar measurements at 35GHz, for the period going from 29th of February to 1rst October 2016, at the Chilbolton observatory in United Kingdom. During this period, more than 40 days with precipitation events are investigated. The investigation uses the synergy of radar reflectivity factors, vertical velocity, Doppler spectrum width, and linear depolarization ratio (LDR) to differentiate between stratiform and convective rain events. The depth of the layer with Doppler spectrum width values greater than 0.5 m s-1 is shown to be a suitable proxy to distinguish between convective and stratiform events. Using LDR to detect the radar bright band, bright band characteristics such as depth of the layer and maximum LDR are shown to vary with the amount of turbulence aloft. Profiles of radar measurements are also compared to rain gauge measurements to study the contribution of convective and stratiform rainfall to total rain duration and amount. To conclude, this study points out differences between convective and stratiform rains and quantifies their contributions over a precipitation event, highlighting that convective and stratiform rainfall should be considered as a continuum rather than a dichotomy.

Is there a preference for linearity when viewing natural images?

NASA Astrophysics Data System (ADS)

Kane, David; Bertamío, Marcelo

2015-01-01

The system gamma of the imaging pipeline, defined as the product of the encoding and decoding gammas, is typically greater than one and is stronger for images viewed with a dark background (e.g. cinema) than those viewed in lighter conditions (e.g. office displays).1-3 However, for high dynamic range (HDR) images reproduced on a low dynamic range (LDR) monitor, subjects often prefer a system gamma of less than one,4 presumably reflecting the greater need for histogram equalization in HDR images. In this study we ask subjects to rate the perceived quality of images presented on a LDR monitor using various levels of system gamma. We reveal that the optimal system gamma is below one for images with a HDR and approaches or exceeds one for images with a LDR. Additionally, the highest quality scores occur for images where a system gamma of one is optimal, suggesting a preference for linearity (where possible). We find that subjective image quality scores can be predicted by computing the degree of histogram equalization of the lightness distribution. Accordingly, an optimal, image dependent system gamma can be computed that maximizes perceived image quality.

[Implants with 32P-foils for LDR-brachytherapy of benign stenosis in urology and gastroenterology].

PubMed

Assmann, Walter; Becker, Ricarda; Otto, Henrike; Bader, Markus; Clemente, Lucas; Reinhardt, Sabine; Schäfer, Claus; Schirra, Jörg; Uschold, Stephanie; Welzmüller, Andreas; Sroka, Ronald

2013-02-01

For LDR-brachytherapy, a limited number of implant geometries and materials are available. To avoid wound healing related hyper-proliferation (stenosis, keloids) a novel radioactive foil system was developed based on beta emitting (32)P, which can be easily integrated in existing implants such as urethral catheters or bile duct stents. As substrate material for these foils PEEK (polyetherethercetone) was chosen because of its radiation hardness during neutron activation of (32)P. The activity was determined by liquid scintillation counting and gamma spectroscopy, dose distributions were measured with scintillation detectors and radiochromic films. The correlation between activity and dose was checked by Monte-Carlo-simulations (Geant4). Prototypes of the (32)P-implants have shown in wash-out tests the required tightness for sealed radioactive sources. In animal tests on urethra and bile duct, the uncomplicated and save application of (32)P-foils mounted on standard implants has been demonstrated, which is almost unchanged due to the simple radiation protection with plexiglass. This concept of radioactive implants with integrated (32)P-foils could extend essentially the application possibilities of LDR-brachytherapy. Copyright © 2012. Published by Elsevier GmbH.

Micro-controller based air pressure monitoring instrumentation system using optical fibers as sensor

NASA Astrophysics Data System (ADS)

Hazarika, D.; Pegu, D. S.

2013-03-01

This paper describes a micro-controller based instrumentation system to monitor air pressure using optical fiber sensors. The principle of macrobending is used to develop the sensor system. The instrumentation system consists of a laser source, a beam splitter, two multi mode optical fibers, two Light Dependent Resistance (LDR) based timer circuits and a AT89S8252 micro-controller. The beam splitter is used to divide the laser beam into two parts and then these two beams are launched into two multi mode fibers. One of the multi mode fibers is used as the sensor fiber and the other one is used as the reference fiber. The use of the reference fiber is to eliminate the environmental effects while measuring the air pressure magnitude. The laser beams from the sensor and reference fibers are applied to two identical LDR based timer circuits. The LDR based timer circuits are interfaced to a micro-controller through its counter pins. The micro-controller samples the frequencies of the timer circuits using its counter-0 and counter-1 and the counter values are then processed to provide the measure of air pressure magnitude.

Development of ProCaRS Clinical Nomograms for Biochemical Failure-free Survival Following Either Low-Dose Rate Brachytherapy or Conventionally Fractionated External Beam Radiation Therapy for Localized Prostate Cancer

PubMed Central

Warner, Andrew; Pickles, Tom; Crook, Juanita; Martin, Andre-Guy; Souhami, Luis; Catton, Charles; Lukka, Himu

2015-01-01

Purpose: Although several clinical nomograms predictive of biochemical failure-free survival (BFFS) for localized prostate cancer exist in the medical literature, making valid comparisons can be challenging due to variable definitions of biochemical failure, the disparate distribution of prognostic factors, and received treatments in patient populations. The aim of this investigation was to develop and validate clinically-based nomograms for 5-year BFFS using the ASTRO II “Phoenix” definition for two patient cohorts receiving low-dose rate (LDR) brachytherapy or conventionally fractionated external beam radiation therapy (EBRT) from a large Canadian multi-institutional database. Methods and Materials: Patients were selected from the GUROC (Genitourinary Radiation Oncologists of Canada) Prostate Cancer Risk Stratification (ProCaRS) database if they received (1) LDR brachytherapy ≥ 144 Gy (n=4208) or (2) EBRT ≥ 70 Gy  (n=822). Multivariable Cox regression analysis for BFFS was performed separately for each cohort and used to generate clinical nomograms predictive of 5-year BFFS. Nomograms were validated using calibration plots of nomogram predicted probability versus observed probability via Kaplan-Meier estimates. Results: Patients receiving LDR brachytherapy had a mean age of 64 ± 7 years, a mean baseline PSA of 6.3 ± 3.0 ng/mL, 75% had a Gleason 6, and 15% had a Gleason 7, whereas patients receiving EBRT had a mean age of 70 ± 6 years, a mean baseline PSA of 11.6 ± 10.7 ng/mL, 30% had a Gleason 6, 55% had a Gleason 7, and 14% had a Gleason 8-10. Nomograms for 5-year BFFS included age, use and duration of androgen deprivation therapy (ADT), baseline PSA, T stage, and Gleason score for LDR brachytherapy and an ADT (months), baseline PSA, Gleason score, and biological effective dose (Gy) for EBRT. Conclusions: Clinical nomograms examining 5-year BFFS were developed for patients receiving either LDR brachytherapy or conventionally fractionated EBRT and may assist clinicians in predicting an outcome. Future work should be directed at examining the role of additional prognostic factors, comorbidities, and toxicity in predicting survival outcomes. PMID:26180700

Using LDR as Sensing Element for an External Fuzzy Controller Applied in Photovoltaic Pumping Systems with Variable-Speed Drives

PubMed Central

Maranhão, Geraldo Neves De A.; Brito, Alaan Ubaiara; Leal, Anderson Marques; Fonseca, Jéssica Kelly Silva; Macêdo, Wilson Negrão

2015-01-01

In the present paper, a fuzzy controller applied to a Variable-Speed Drive (VSD) for use in Photovoltaic Pumping Systems (PVPS) is proposed. The fuzzy logic system (FLS) used is embedded in a microcontroller and corresponds to a proportional-derivative controller. A Light-Dependent Resistor (LDR) is used to measure, approximately, the irradiance incident on the PV array. Experimental tests are executed using an Arduino board. The experimental results show that the fuzzy controller is capable of operating the system continuously throughout the day and controlling the direct current (DC) voltage level in the VSD with a good performance. PMID:26402688

Linear Depolarization of Lidar Returns by Aged Smoke Particles

NASA Technical Reports Server (NTRS)

Mishchenko, Michael I.; Dlugach, Janna M.; Liu, Li

2016-01-01

We use the numerically exact (superposition) T-matrix method to analyze recent measurements of the backscattering linear depolarization ratio (LDR) for a plume of aged smoke at lidar wavelengths ranging from 355 to 1064 nm. We show that the unique spectral dependence of the measured LDRs can be modeled, but only by assuming expressly nonspherical morphologies of smoke particles containing substantial amounts of nonabsorbing (or weakly absorbing) refractory materials such as sulfates. Our results demonstrate that spectral backscattering LDR measurements can be indicative of the presence of morphologically complex smoke particles, but additional (e.g., passive polarimetric or bistatic lidar) measurements may be required for a definitive characterization of the particle morphology and composition.

2nd Generation Airborne Precipitation Radar (APR-2)

NASA Technical Reports Server (NTRS)

Durden, S.; Tanelli, S.; Haddad, Z.; Im, E.

2012-01-01

Dual-frequency operation with Ku-band (13.4 GHz) and Ka-band (35.6 GHz). Geometry and frequencies chosen to simulate GPM radar. Measures reflectivity at co- and cross-polarizations, and Doppler. Range resolution is approx. 60 m. Horizontal resolution at surface is approx. 1 km. Reflectivity calibration is within 1.5 dB, based on 10 deg sigmaO at Ku-band and Mie scattering calculations in light rain at Ka-band. LDR measurements are OK to near -20 dB; LDR lower than this is likely contaminated by system cross-polarization isolation. Velocity is motion-corrected total Doppler, including particle fall speed. Aliasing can be seen in some places; can usually be dealiased with an algorithm. .

A JPEG backward-compatible HDR image compression

NASA Astrophysics Data System (ADS)

Korshunov, Pavel; Ebrahimi, Touradj

2012-10-01

High Dynamic Range (HDR) imaging is expected to become one of the technologies that could shape next generation of consumer digital photography. Manufacturers are rolling out cameras and displays capable of capturing and rendering HDR images. The popularity and full public adoption of HDR content is however hindered by the lack of standards in evaluation of quality, file formats, and compression, as well as large legacy base of Low Dynamic Range (LDR) displays that are unable to render HDR. To facilitate wide spread of HDR usage, the backward compatibility of HDR technology with commonly used legacy image storage, rendering, and compression is necessary. Although many tone-mapping algorithms were developed for generating viewable LDR images from HDR content, there is no consensus on which algorithm to use and under which conditions. This paper, via a series of subjective evaluations, demonstrates the dependency of perceived quality of the tone-mapped LDR images on environmental parameters and image content. Based on the results of subjective tests, it proposes to extend JPEG file format, as the most popular image format, in a backward compatible manner to also deal with HDR pictures. To this end, the paper provides an architecture to achieve such backward compatibility with JPEG and demonstrates efficiency of a simple implementation of this framework when compared to the state of the art HDR image compression.

Lung damage following bone marrow transplantation. II. The contribution of cyclophosphamide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Varekamp, A.E.; de Vries, A.J.; Zurcher, C.

1987-10-01

The effect of high-dose cyclophosphamide (Cy), either alone or in combination with irradiation, upon the development of interstitial pneumonitis (IP) after bone marrow transplantation (BMT) was investigated in a Brown Norway rat model. The parameters that were examined included ventilation rate, mortality, and histopathology. No damage to the lungs was observed in rats given Cy alone in supralethal dosages plus BMT, and mortality resulted from severe aplasia of hemopoietic and lymphoid tissues with multifocal hemorrhages, secondary infections, and sepsis. Two separate periods of mortality were observed within the first 180 days following whole thorax irradiation with a high dose ratemore » (HDR; 0.8 Gy/min) or a low dose rate (LDR; 0.05 Gy/min). The addition of Cy prior to irradiation resulted in an increased mortality in the first period (before day 100) in all experimental groups. The influence of Cy on mortality at 180 days however, was different for the HDR and LDR experiments. The LD50-180 after HDR irradiation, dose range 8 to 18 Gy, was not significantly altered by the addition of Cy (100 mg/kg) 1 day prior to irradiation, whereas Cy (100 mg/kg) 1 day prior to LDR irradiation, dose range: 16 to 24 Gy, caused an enhancement of radiation damage with a decrease of the LD50-180 by 1.33 Gy. The dose modification factor (DMF) was 1.07. This enhancement was no longer significant after splitting up the dose of Cy in two dosages of 50 mg/kg given on 2 consecutive days prior to irradiation with a LDR. The extrapolation of the data in this rat model to available dose-response curves on IP after BMT and radiation pneumonitis in humans, implied that non-infectious IP is a radiation pneumonitis that is only slightly enhanced by Cy.« less

1998 report on Hanford Site land disposal restrictions for mixed waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Black, D.G.

1998-04-10

This report was submitted to meet the requirements of Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) Milestone M-26-01H. This milestone requires the preparation of an annual report that covers characterization, treatment, storage, minimization, and other aspects of managing land-disposal-restricted mixed waste at the Hanford Facility. The US Department of Energy, its predecessors, and contractors on the Hanford Facility were involved in the production and purification of nuclear defense materials from the early 1940s to the late 1980s. These production activities have generated large quantities of liquid and solid mixed waste. This waste is regulated under authority of bothmore » the Resource Conservation and Recovery Act of l976 and the Atomic Energy Act of 1954. This report covers only mixed waste. The Washington State Department of Ecology, US Environmental Protection Agency, and US Department of Energy have entered into the Tri-Party Agreement to bring the Hanford Facility operations into compliance with dangerous waste regulations. The Tri-Party Agreement required development of the original land disposal restrictions (LDR) plan and its annual updates to comply with LDR requirements for mixed waste. This report is the eighth update of the plan first issued in 1990. The Tri-Party Agreement requires and the baseline plan and annual update reports provide the following information: (1) Waste Characterization Information -- Provides information about characterizing each LDR mixed waste stream. The sampling and analysis methods and protocols, past characterization results, and, where available, a schedule for providing the characterization information are discussed. (2) Storage Data -- Identifies and describes the mixed waste on the Hanford Facility. Storage data include the Resource Conservation and Recovery Act of 1976 dangerous waste codes, generator process knowledge needed to identify the waste and to make LDR determinations, quantities stored, generation rates, location and method of storage, an assessment of storage-unit compliance status, storage capacity, and the bases and assumptions used in making the estimates.« less

Alzheimer ’s Disease: Possible Mechanisms Behind Neurohormesis Induced by Exposure to Low Doses of Ionizing Radiation

PubMed Central

Bevelacqua, J.J.; Mortazavi, S.M.J.

2018-01-01

In 2016, scientists reported that human exposure to low doses of ionizing radiation (CT scans of the brain) might relieve symptoms of both Alzheimer’s disease (AD) and Parkinson disease (PD). The findings were unbelievable for those who were not familiar with neurohormesis. X-ray stimulation of the patient’s adaptive protection systems against neurodegenerative diseases was the mechanism proposed by those authors. Now, some more recent studies performed in the field of neurobiological research confirm that low levels of stress can produce protective responses against the pathogenic processes. This paper outlines possible protective consequences of LDR in preventing the pathogenesis of AD through mechanisms such as restoring the myelin sheath and preventing neurodegeneration caused by oxidative stress. Focal demyelination is frequently reported in the proximity of beta-amyloid plaques within neocortex. Extracellular accumulation of amyloid is among well-characterized pathological changes in AD. It should be noted that LDR has been shown to contribute to the regeneration and functional recovery after transverse peripheral nerve injury (through inducing increased production of VEGF and GAP-43), which advances both the axonal regeneration and myelination. Another mechanism which is possibly involved is preventing neurodegeneration caused by oxidative stress. While high doses can induce reactive oxygen species (ROS) formation, oxidative stress and neuro-inflammation, substantial evidence now indicates that LDR can mitigate tissue damage through antioxidant defenses. Although adult neurogenesis has been reported to be beneficial for the regeneration of nervous system, some studies demonstrate that neurogenesis increases in AD brains. In spite of these reports, cellular therapy is introduced as a promising strategy for AD, and hence, LDR can affect the proliferation and differentiation of neural stem cells. Although such mechanisms are not fully known yet, it is hoped that this paper would foster further investigation into the mechanisms of this phenomenon, which accordingly improves human health.

Chloroquine Improves Survival and Hematopoietic Recovery After Lethal Low-Dose-Rate Radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lim Yiting; Hedayati, Mohammad; Merchant, Akil A.

2012-11-01

Purpose: We have previously shown that the antimalarial agent chloroquine can abrogate the lethal cellular effects of low-dose-rate (LDR) radiation in vitro, most likely by activating the ataxia-telangiectasia mutated (ATM) protein. Here, we demonstrate that chloroquine treatment also protects against lethal doses of LDR radiation in vivo. Methods and Materials: C57BL/6 mice were irradiated with a total of 12.8 Gy delivered at 9.4 cGy/hour. ATM null mice from the same background were used to determine the influence of ATM. Chloroquine was administered by two intraperitoneal injections of 59.4 {mu}g per 17 g of body weight, 24 hours and 4 hoursmore » before irradiation. Bone marrow cells isolated from tibia, fibula, and vertebral bones were transplanted into lethally irradiated CD45 congenic recipient mice by retroorbital injection. Chimerism was assessed by flow cytometry. In vitro methylcellulose colony-forming assay of whole bone marrow cells and fluorescence activated cell sorting analysis of lineage depleted cells were used to assess the effect of chloroquine on progenitor cells. Results: Mice pretreated with chloroquine before radiation exhibited a significantly higher survival rate than did mice treated with radiation alone (80% vs. 31%, p = 0.0026). Chloroquine administration before radiation did not affect the survival of ATM null mice (p = 0.86). Chloroquine also had a significant effect on the early engraftment of bone marrow cells from the irradiated donor mice 6 weeks after transplantation (4.2% vs. 0.4%, p = 0.015). Conclusion: Chloroquine administration before radiation had a significant effect on the survival of normal but not ATM null mice, strongly suggesting that the in vivo effect, like the in vitro effect, is also ATM dependent. Chloroquine improved the early engraftment of bone marrow cells from LDR-irradiated mice, presumably by protecting the progenitor cells from radiation injury. Chloroquine thus could serve as a very useful drug for protection against the harmful effects of LDR radiation.« less

Utilizing time-driven activity-based costing to understand the short- and long-term costs of treating localized, low-risk prostate cancer.

PubMed

Laviana, Aaron A; Ilg, Annette M; Veruttipong, Darlene; Tan, Hung-Jui; Burke, Michael A; Niedzwiecki, Douglas R; Kupelian, Patrick A; King, Chris R; Steinberg, Michael L; Kundavaram, Chandan R; Kamrava, Mitchell; Kaplan, Alan L; Moriarity, Andrew K; Hsu, William; Margolis, Daniel J A; Hu, Jim C; Saigal, Christopher S

2016-02-01

Given the costs of delivering care for men with prostate cancer remain poorly described, this article reports the results of time-driven activity-based costing (TDABC) for competing treatments of low-risk prostate cancer. Process maps were developed for each phase of care from the initial urologic visit through 12 years of follow-up for robotic-assisted laparoscopic prostatectomy (RALP), cryotherapy, high-dose rate (HDR) and low-dose rate (LDR) brachytherapy, intensity-modulated radiation therapy (IMRT), stereotactic body radiation therapy (SBRT), and active surveillance (AS). The last modality incorporated both traditional transrectal ultrasound (TRUS) biopsy and multiparametric-MRI/TRUS fusion biopsy. The costs of materials, equipment, personnel, and space were calculated per unit of time and based on the relative proportion of capacity used. TDABC for each treatment was defined as the sum of its resources. Substantial cost variation was observed at 5 years, with costs ranging from $7,298 for AS to $23,565 for IMRT, and they remained consistent through 12 years of follow-up. LDR brachytherapy ($8,978) was notably cheaper than HDR brachytherapy ($11,448), and SBRT ($11,665) was notably cheaper than IMRT, with the cost savings attributable to shorter procedure times and fewer visits required for treatment. Both equipment costs and an inpatient stay ($2,306) contributed to the high cost of RALP ($16,946). Cryotherapy ($11,215) was more costly than LDR brachytherapy, largely because of increased single-use equipment costs ($6,292 vs $1,921). AS reached cost equivalence with LDR brachytherapy after 7 years of follow-up. The use of TDABC is feasible for analyzing cancer services and provides insights into cost-reduction tactics in an era focused on emphasizing value. By detailing all steps from diagnosis and treatment through 12 years of follow-up for low-risk prostate cancer, this study has demonstrated significant cost variation between competing treatments. © 2015 American Cancer Society.

Patterns of Recurrence After Low-Dose-Rate Prostate Brachytherapy: A Population-Based Study of 2223 Consecutive Low- and Intermediate-Risk Patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lo, Andrea C.; Morris, W. James, E-mail: JMorris@bccancer.bc.ca; Pickles, Tom

Objectives: This study examined patterns of recurrence after low–dose-rate prostate brachytherapy (LDR-PB), estimated local recurrence rate and compared that rate to the estimated local recurrence rate after radical prostatectomy (RP). Methods and Materials: A prospective database was maintained with clinical, dosimetric, and outcome data for all LDR-PB implantation procedures performed at our institution. From 1998 to 2008, 2223 patients with prostate cancer received LDR-PB without supplemental external beam radiation therapy. Patients who developed Phoenix-defined biochemical failure were reviewed for sites of relapse and investigations completed. Results: At a median follow-up of 5 years, 108 of 2223 patients (4.8%) developed biochemical relapse.more » In 1 additional patient, local relapse was found on transurethral prostate resection, but his prostate-specific antigen concentration was well short of triggering Phoenix-defined failure. Of the 109 patients with disease relapse, 18 of 2223 (0.8%) had a proven local recurrence, and 30 of 2223 (1.3%) had a proven distant recurrence. The remaining 61 of 2223 patients (2.7%) had unidentified sites of recurrence; of these, 57 patients (93%) had digital rectal examinations (DREs), 18 (30%) had post-treatment biopsies, 45 (74%) had bone scans, and 34 (56%) had computed tomography imaging of the abdomen and pelvis. If every biochemical failure were local, the local recurrence rate would be as high as 4.9%; however, by excluding those with proven distant failure and those with both a negative DRE and biopsy, we estimate that the local recurrence rate is 2.7% or less. Conclusions: In the context of limitations of the study design, our population-based analysis indicates that the local recurrence rate after LDR-PB is as low or lower than that after RP in our jurisdiction.« less

Absolute measurement of LDR brachytherapy source emitted power: Instrument design and initial measurements.

PubMed

Malin, Martha J; Palmer, Benjamin R; DeWerd, Larry A

2016-02-01

Energy-based source strength metrics may find use with model-based dose calculation algorithms, but no instruments exist that can measure the energy emitted from low-dose rate (LDR) sources. This work developed a calorimetric technique for measuring the power emitted from encapsulated low-dose rate, photon-emitting brachytherapy sources. This quantity is called emitted power (EP). The measurement methodology, instrument design and performance, and EP measurements made with the calorimeter are presented in this work. A calorimeter operating with a liquid helium thermal sink was developed to measure EP from LDR brachytherapy sources. The calorimeter employed an electrical substitution technique to determine the power emitted from the source. The calorimeter's performance and thermal system were characterized. EP measurements were made using four (125)I sources with air-kerma strengths ranging from 2.3 to 5.6 U and corresponding EPs of 0.39-0.79 μW, respectively. Three Best Medical 2301 sources and one Oncura 6711 source were measured. EP was also computed by converting measured air-kerma strengths to EPs through Monte Carlo-derived conversion factors. The measured EP and derived EPs were compared to determine the accuracy of the calorimeter measurement technique. The calorimeter had a noise floor of 1-3 nW and a repeatability of 30-60 nW. The calorimeter was stable to within 5 nW over a 12 h measurement window. All measured values agreed with derived EPs to within 10%, with three of the four sources agreeing to within 4%. Calorimeter measurements had uncertainties ranging from 2.6% to 4.5% at the k = 1 level. The values of the derived EPs had uncertainties ranging from 2.9% to 3.6% at the k = 1 level. A calorimeter capable of measuring the EP from LDR sources has been developed and validated for (125)I sources with EPs between 0.43 and 0.79 μW.

Biphasic and monophasic repair: comparative implications for biologically equivalent dose calculations in pulsed dose rate brachytherapy of cervical carcinoma

PubMed Central

Millar, W T; Davidson, S E

2013-01-01

Objective: To consider the implications of the use of biphasic rather than monophasic repair in calculations of biologically-equivalent doses for pulsed-dose-rate brachytherapy of cervix carcinoma. Methods: Calculations are presented of pulsed-dose-rate (PDR) doses equivalent to former low-dose-rate (LDR) doses, using biphasic vs monophasic repair kinetics, both for cervical carcinoma and for the organ at risk (OAR), namely the rectum. The linear-quadratic modelling calculations included effects due to varying the dose per PDR cycle, the dose reduction factor for the OAR compared with Point A, the repair kinetics and the source strength. Results: When using the recommended 1 Gy per hourly PDR cycle, different LDR-equivalent PDR rectal doses were calculated depending on the choice of monophasic or biphasic repair kinetics pertaining to the rodent central nervous and skin systems. These differences virtually disappeared when the dose per hourly cycle was increased to 1.7 Gy. This made the LDR-equivalent PDR doses more robust and independent of the choice of repair kinetics and α/β ratios as a consequence of the described concept of extended equivalence. Conclusion: The use of biphasic and monophasic repair kinetics for optimised modelling of the effects on the OAR in PDR brachytherapy suggests that an optimised PDR protocol with the dose per hourly cycle nearest to 1.7 Gy could be used. Hence, the durations of the new PDR treatments would be similar to those of the former LDR treatments and not longer as currently prescribed. Advances in knowledge: Modelling calculations indicate that equivalent PDR protocols can be developed which are less dependent on the different α/β ratios and monophasic/biphasic kinetics usually attributed to normal and tumour tissues for treatment of cervical carcinoma. PMID:23934965

Low-dose-rate or high-dose-rate brachytherapy in treatment of prostate cancer – between options

PubMed Central

2013-01-01

Purpose Permanent low-dose-rate (LDR-BT) and temporary high-dose-rate (HDR-BT) brachytherapy are competitive techniques for clinically localized prostate radiotherapy. Although a randomized trial will likely never to be conducted comparing these two forms of brachytherapy, a comparative analysis proves useful in understanding some of their intrinsic differences, several of which could be exploited to improve outcomes. The aim of this paper is to look for possible similarities and differences between both brachytherapy modalities. Indications and contraindications for monotherapy and for brachytherapy as a boost to external beam radiation therapy (EBRT) are presented. It is suggested that each of these techniques has attributes that advocates for one or the other. First, they represent the extreme ends of the spectrum with respect to dose rate and fractionation, and therefore have inherently different radiobiological properties. Low-dose-rate brachytherapy has the great advantage of being practically a one-time procedure, and enjoys a long-term follow-up database supporting its excellent outcomes and low morbidity. Low-dose-rate brachytherapy has been a gold standard for prostate brachytherapy in low risk patients since many years. On the other hand, HDR is a fairly invasive procedure requiring several sessions associated with a brief hospital stay. Although lacking in significant long-term data, it possesses the technical advantage of control over its postimplant dosimetry (by modulating the source dwell time and position), which is absent in LDR brachytherapy. This important difference in dosimetric control allows HDR doses to be escalated safely, a flexibility that does not exist for LDR brachytherapy. Conclusions Radiobiological models support the current clinical evidence for equivalent outcomes in localized prostate cancer with either LDR or HDR brachytherapy, using current dose regimens. At present, all available clinical data regarding these two techniques suggests that they are equally effective, stage for stage, in providing high tumor control rates. PMID:23634153

Dose reduction in LDR brachytherapy by implanted prostate gold fiducial markers.

PubMed

Landry, Guillaume; Reniers, Brigitte; Lutgens, Ludy; Murrer, Lars; Afsharpour, Hossein; de Haas-Kock, Danielle; Visser, Peter; van Gils, Francis; Verhaegen, Frank

2012-03-01

The dosimetric impact of gold fiducial markers (FM) implanted prior to external beam radiotherapy of prostate cancer on low dose rate (LDR) brachytherapy seed implants performed in the context of combined therapy was investigated. A virtual water phantom was designed containing a single FM. Single and multi source scenarios were investigated by performing Monte Carlo dose calculations, along with the influence of varying orientation and distance of the FM with respect to the sources. Three prostate cancer patients treated with LDR brachytherapy for a recurrence following external beam radiotherapy with implanted FM were studied as surrogate cases to combined therapy. FM and brachytherapy seeds were identified on post implant CT scans and Monte Carlo dose calculations were performed with and without FM. The dosimetric impact of the FM was evaluated by quantifying the amplitude of dose shadows and the volume of cold spots. D(90) was reported based on the post implant CT prostate contour. Large shadows are observed in the single source-FM scenarios. As expected from geometric considerations, the shadows are dependent on source-FM distance and orientation. Large dose reductions are observed at the distal side of FM, while at the proximal side a dose enhancement is observed. In multisource scenarios, the importance of shadows appears mitigated, although FM at the periphery of the seed distribution caused underdosage (

CSU-CHILL Polarimetric Radar Measurements from a Severe Hail Storm in Eastern Colorado.

NASA Astrophysics Data System (ADS)

Hubbert, J.; Bringi, V. N.; Carey, L. D.; Bolen, S.

1998-08-01

Polarimetric radar measurements made by the recently upgraded CSU-CHILL radar system in a severe hailstorm are analyzed permitting for the first time the combined use of Zh, ZDR, linear depolarization ratio (LDR), KDP, and h to infer hydrometeor types. A chase van equipped for manual collection of hail, and instrumented with a rain gauge, intercepted the storm core for 50 min. The period of golfball-sized hail is easily distinguished by high LDR (greater than or equal to 18 dB), negative ZDR (less than or equal to 0.5 dB), and low h (less than or equal to 0.93) values near the surface. Rainfall accumulation over the entire event (about 40 mm) estimated using KDP is in excellent agreement with the rain gauge measurement. Limited dual-Doppler synthesis using the CSU-CHILL and Denver WSR-88D radars permit estimates of the horizontal convergence at altitudes less than 3 km above ground level (AGL) at 1747 and 1812 mountain daylight time (MDT). Locations of peak horizontal convergence at these times are centered on well-defined positive ZDR columns. Vertical sections of multiparameter radar data at 1812 MDT are interpreted in terms of hydrometeor type. In particular, an enhanced LDR `cap' area on top of the the positive ZDR column is interpreted as a region of mixed phase with large drops mixed with partially frozen and frozen hydrometeors. A positive KDP column on the the western fringe of the main updraft is inferred to be the result of drops (1-2 mm) shed by wet hailstones. Swaths of large hail at the surface (inferred from LDR signatures) and positive ZDR at 3.5 km AGL suggest that potential frozen drop embryos are favorably located for growth into large hailstones. Thin section analysis of a sample of the large hailstones shows that 30%-40% have frozen drop embryos.

Comparison of acute proton, photon, and low-dose priming effects on genes associated with extracellular matrix and adhesion molecules in the lungs

PubMed Central

2013-01-01

Background Crew members on space missions inevitably are exposed to low background radiation and can receive much higher doses during solar particle events (SPE) that consist primarily of protons. Ionizing radiation could cause lung pathologies. Cell adhesion molecules (CAM) are believed to participate in fibrogenesis. Interactions between CAM and extracellular matrix (ECM) affect epithelial repair mechanisms in the lung. However, there are very limited data on biological effects of protons on normal lung tissue. Numerous reports have shown that exposure to low-dose/low-dose-rate (LDR) radiation can result in radioadaptation that renders cells more resistant to subsequent acute radiation. The goal of this study was to compare expression of genes associated with ECM and CAM, as well as critical profibrotic mediators, in mouse lungs after acute irradiation with photons and protons, and also determine whether pre-exposure to LDR γ-rays induces an adaptive effect. Results Overall, a marked difference was present in the proton vs. photon groups in gene expression. When compared to 0 Gy, more genes were affected by protons than by photons at both time points (11 vs. 6 on day 21 and 14 vs. 8 on day 56), and all genes affected by protons were upregulated. Many genes were modulated by LDR γ-rays when combined with photons or protons. Col1a1, mmp14, and mmp15 were significantly upregulated by all radiation regimens on day 21. Similarly, the change in expression of profibrotic proteins was also detected after acute and combination irradiation. Conclusion These data show that marked differences were present between acutely delivered protons and photons in modulating genes, and the effect of protons was more profound than that of photons. Pre-exposure to LDR γ-rays ‘normalized’ some genes that were modified by acute irradiation. PMID:23374750

SU-F-T-42: MRI and TRUS Image Fusion as a Mode of Generating More Accurate Prostate Contours

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petronek, M; Purysko, A; Balik, S

Purpose: Transrectal Ultrasound (TRUS) imaging is utilized intra-operatively for LDR permanent prostate seed implant treatment planning. Prostate contouring with TRUS can be challenging at the apex and base. This study attempts to improve accuracy of prostate contouring with MRI-TRUS fusion to prevent over- or under-estimation of the prostate volume. Methods: 14 patients with previous MRI guided prostate biopsy and undergone an LDR permanent prostate seed implant have been selected. The prostate was contoured on the MRI images (1 mm slice thickness) by a radiologist. The prostate was also contoured on TRUS images (5 mm slice thickness) during LDR procedure bymore » a urologist. MRI and TRUS images were rigidly fused manually and the prostate contours from MRI and TRUS were compared using Dice similarity coefficient, percentage volume difference and length, height and width differences. Results: The prostate volume was overestimated by 8 ± 18% (range: 34% to −25%) in TRUS images compared to MRI. The mean Dice was 0.77 ± 0.09 (range: 0.53 to 0.88). The mean difference (TRUS-MRI) in the prostate width was 0 ± 4 mm (range: −11 to 5 mm), height was −3 ± 6 mm (range: −13 to 6 mm) and length was 6 ± 6 (range: −10 to 16 mm). Prostate was overestimated with TRUS imaging at the base for 6 cases (mean: 8 ± 4 mm and range: 5 to 14 mm), at the apex for 6 cases (mean: 11 ± 3 mm and range: 5 to 15 mm) and 1 case was underestimated at both base and apex by 4 mm. Conclusion: Use of intra-operative TRUS and MRI image fusion can help to improve the accuracy of prostate contouring by accurately accounting for prostate over- or under-estimations, especially at the base and apex. The mean amount of discrepancy is within a range that is significant for LDR sources.« less

Regulated Cell Death of Lymphoma Cells after Graded Mitochondrial Damage is Differentially Affected by Drugs Targeting Cell Stress Responses.

PubMed

Lombardo, Tomás; Folgar, Martín Gil; Salaverry, Luciana; Rey-Roldán, Estela; Alvarez, Elida M; Carreras, María C; Kornblihtt, Laura; Blanco, Guillermo A

2018-05-01

Collapse of the mitochondrial membrane potential (MMP) is often considered the initiation of regulated cell death (RCD). Carbonyl cyanide 3-chlorophenylhydrazone (CCCP) is an uncoupler of the electron transport chain (ETC) that facilitates the translocation of protons into the mitochondrial matrix leading to the collapse of the MMP. Several cell stress responses such as mitophagy, mitochondrial biogenesis and the ubiquitin proteasome system may differentially contribute to restrain the initiation of RCD depending on the extent of mitochondrial damage. We induced graded mitochondrial damage after collapse of MMP with the mitochondrial uncoupler CCCP in Burkitt's lymphoma cells, and we evaluated the effect of several drugs targeting cell stress responses over RCD at 72 hr, using a multiparametric flow cytometry approach. CCCP caused collapse of MMP after 30 min., massive mitochondrial fission, oxidative stress and increased mitophagy within the 5-15 μM low-dose range (LDR) of CCCP. Within the 20-50 μM high-dose range (HDR), CCCP caused lysosomal destabilization and rupture, thus precluding mitophagy and autophagy. Cell death after 72 hr was below 20%, with increased mitochondrial mass (MM). The inhibitors of mitophagy 3-(2,4-dichloro-5-methoxyphenyl)-2,3-dihydro-2-thioxo-4(1H)-quinazolinone (Mdivi-1) and vincristine (VCR) increased cell death from CCCP within the LDR, while valproic acid (an inducer of mitochondrial biogenesis) also increased MM and cell death within the LDR. The proteasome inhibitor, MG132, increased cell death only in the HDR. Doxycycline, an antibiotic that disrupts mitochondrial biogenesis, had no effect on cell survival, while iodoacetamide, an inhibitor of glycolysis, increased cell death at the HDR. We conclude that mitophagy influenced RCD of lymphoma cells after MMP collapse by CCCP only within the LDR, while proteasome activity and glycolysis contributed to survival in the HDR under extensive mitochondria and lysosome damage. © 2017 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

X-43A Flight Controls

NASA Technical Reports Server (NTRS)

Baumann, Ethan

2006-01-01

A viewgraph presentation detailing X-43A Flight controls at NASA Dryden Flight Research Center is shown. The topics include: 1) NASA Dryden, Overview and current and recent flight test programs; 2) Unmanned Aerial Vehicle Synthetic Aperture Radar (UAVSAR) Program, Program Overview and Platform Precision Autopilot; and 3) Hyper-X Program, Program Overview, X-43A Flight Controls and Flight Results.

Thunderstorm Program General Overview

DTIC Science & Technology

2014-12-19

DISTRIBUTION A. APPROVED FOR PUBLIC RELEASE; DISTRIBUTION IS UNLIMITED. Thunderstorm Program General Overview Report Documentation Page Form...COVERED - 4. TITLE AND SUBTITLE Thunderstorm Program General Overview 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...original document contains color images. 14. ABSTRACT Thunderstorm provides OSD, interagency partners, Combatant Commanders, Services, academia

Structural overview and learner control in hypermedia instructional programs

NASA Astrophysics Data System (ADS)

Burke, Patricia Anne

1998-09-01

This study examined the effects of a structural overview and learner control in a computer-based program on the achievement, attitudes, time in program and Linearity of path of fifth-grade students. Four versions of a computer-based instructional program about the Sun and planets were created in a 2 x 2 factorial design. The program consisted of ten sections, one for each planet and one for the Sun. Two structural overview conditions (structural overview, no structural overview) were crossed with two control conditions (learner control, program control). Subjects in the structural overview condition chose the order in which they would learn about the planets from among three options: ordered by distance from the Sun, ordered by size, or ordered by temperature. Subjects in the learner control condition were able to move freely among screens within a section and to choose their next section after finishing the previous one. In contrast, those in the program control condition advanced through the program in a prescribed linear manner. A 2 x 2 ANOVA yielded no significant differences in posttest scores for either independent variable or for their interaction. The structural overview was most likely not effective because subjects spent only a small percentage of their total time on the structural overview screens and they were not required to act upon the information in those screens. Learner control over content sequencing may not have been effective because most learner-control subjects chose the same overall sequence of instruction (i.e., distance from the Sun) prescribed for program-control subjects. Learner-control subjects chose to view an average of 40 more screens than the fixed number of 160 screens in the program-control version. However, program-control subjects spent significantly more time per screen than learner-control subjects, and the total time in program did not differ significantly between the two groups. Learner-control subjects receiving the structural overview deviated from the linear path significantly more often than subjects who did not have the structural overview, but deviation from the linear path was not associated with higher posttest scores.

Watershed health assessment to monitor land degradation

NASA Astrophysics Data System (ADS)

Hamidreza Sadeghi, Seyed; Hazbavi, Zeinab; Cerdà, Artemi

2017-04-01

Land degradation is a worldwide issue that affects the Planet and the fate of the humankind (Cerdà et al., 2009; Choudhury et al., 2016; Fernández et al., 2016; Ferreira et al., 2016). Several processes affect the sustainability of the ecosystems, from soil erosion to soil compation, deforestation, Climate Change or water, soil and air pollution (Sadeghi et al., 2015a; 2015b; Gómez-Acanta et al., 2016; Mengistu et al., 2016; Mukai, 2016). Several ecosystem theories have been presented in the scientific literatures to monitor land degradation (Cerdà et al., 2016; Davudirad et al., 2016; Fava et al., 2016; Mahyou et al., 2016; Soulard et al., 2016). Besides the scientific tasks of improving the indication, the conviction of the potential users to change their concepts toward a higher consideration of ecosystem attributes, and toward a fruitful application of the health or integrity concepts, will be a main task of future activities. Reliability, resilience and vulnerability (R-R-V) indicators are often used in combination for quantifying risk and decision making in many systems. However, the use of hydrological series data for R-R-V computations has been rather limited. Toward this, the overall objective of this paper is to conduct a risk assessment analysis on stream flow discharge from Shazand Watershed located in the south western of Markazi Province in Iran for the period of 1972-2014 using R-R-V indicators. Based on the R-R-V analysis conducted in this study, the stream flow discharge of the study region followed a cyclic pattern with a decreasing trend. The results further showed a decreasing trend in reliability and resilience and an increasing trend in vulnerability in the Shazand Watershed. It may be concluded that the Shazand Watershed was in overall in unhealthy condition from view of stream flow discharge. Acknowledgements This research was funded by the European Union Seventh Framework Programme (FP7/2007-2013) under grant no. 603498 (RECARE Project). References Cerdà, A., A. G. Morera, and M. B. Bodí. 2009. Soil and Water Losses from New Citrus Orchards Growing on Sloped Soils in the Western Mediterranean Basin. Earth Surface Processes and Landforms 34 (13): 1822-1830. doi:10.1002/esp.1889. Cerdà, A., González-Pelayo, O., Giménez-Morera, A., Jordán, A., Pereira, P., Novara, A., Brevik, E.C., Prosdocimi, M., Mahmoodabadi, M., Keesstra, S., García Orenes, F., Ritsema, C., 2016. The use of barley straw residues to avoid high erosion and runoff rates on persimmon plantations in Eastern Spain under low frequency - high magnitude simulated rainfall events. Soil Res, 54, 2, 154-165 DOI: 10.1071/SR15092 Choudhury, B. U., A. R. Fiyaz, K. P. Mohapatra, and S. Ngachan. 2016. Impact of Land Uses, Agrophysical Variables and Altitudinal Gradient on Soil Organic Carbon Concentration of North-Eastern Himalayan Region of India. Land Degradation and Development 27 (4): 1163-1174. doi:10.1002/ldr.2338. Davudirad, A. A., S. H. Sadeghi, and A. Sadoddin. 2016. The Impact of Development Plans on Hydrological Changes in the Shazand Watershed, Iran. Land Degradation and Development 27 (4): 1236-1244. doi:10.1002/ldr.2523. Fava, F., G. Pulighe, and A. T. Monteiro. 2016. Mapping Changes in Land Cover Composition and Pattern for Comparing Mediterranean Rangeland Restoration Alternatives. Land Degradation and Development 27 (3): 671-681. doi:10.1002/ldr.2456. Fernández-Romero, M. L., B. Lozano-García, L. Parras-Alcántara, C. D. Collins, and J. M. Clark. 2016. Effects of Land Management on Different Forms of Soil Carbon in Olive Groves in Mediterranean Areas. Land Degradation and Development 27 (4): 1186-1195. doi:10.1002/ldr.2327. Ferreira, A. C. C., L. F. C. Leite, A. S. F. de Araújo, and N. Eisenhauer. 2016. Land-use Type Effects on Soil Organic Carbon and Microbial Properties in a Semi-Arid Region of Northeast Brazil. Land Degradation and Development 27 (2): 171-178. doi:10.1002/ldr.2282. Gómez-Acata, E. S., I. Valencia-Becerril, C. Valenzuela-Encinas, A. S. Velásquez-Rodríguez, Y. E. Navarro-Noya, N. Montoya-Ciriaco, M. C. Suárez-Arriaga, et al. 2016. Deforestation and Cultivation with Maize (Zea Mays L.) has a Profound Effect on the Bacterial Community Structure in Soil. Land Degradation and Development 27 (4): 1122-1130. doi:10.1002/ldr.2328. Mahyou, H., B. Tychon, R. Balaghi, M. Louhaichi, and J. Mimouni. 2016. A Knowledge-Based Approach for Mapping Land Degradation in the Arid Rangelands of North Africa. Land Degradation and Development. doi:10.1002/ldr.2470. Mengistu, D., W. Bewket, and R. Lal. 2016. Conservation Effects on Soil Quality and Climate Change Adaptability of Ethiopian Watersheds. Land Degradation and Development 27 (6): 1603-1621. doi:10.1002/ldr.2376. Mukai, S. 2016. Gully Erosion Rates and Analysis of Determining Factors: A Case Study from the Semi-Arid Main Ethiopian Rift Valley. Land Degradation and Development. doi:10.1002/ldr.2532. Sadeghi, S.H.R., Gholami, L., Homaee, M., Khaledi Darvishan, A. 2015. Reducing sediment concentration and soil loss using organic and inorganic amendments at plot scale. Solid Earth, 6 (2), pp. 445-455. DOI: http://dx.doi.org/10.5194/se-6-445-2015 Sadeghi, S.H.R., Gholami, L., Sharifi, E., Khaledi Darvishan, A., Homaee, M. 2015. Scale effect on runoff and soil loss control using rice straw mulch under laboratory conditions. Solid Earth, 6 (1), pp. 1-8.. DOI: http://dx.doi.org/10.5194/se-6-1-2015 Soulard, C. E., W. Acevedo, S. V. Stehman, and O. P. Parker. 2016. Mapping Extent and Change in Surface Mines within the United States for 2001 to 2006. Land Degradation and Development 27 (2): 248-257. doi:10.1002/ldr.2412.

Performance Evaluation of a Bedside Cardiac SPECT System

NASA Astrophysics Data System (ADS)

Studenski, Matthew T.; Gilland, David R.; Parker, Jason G.; Hammond, B.; Majewski, Stan; Weisenberger, Andrew G.; Popov, Vladimir

2009-06-01

This paper reports on the initial performance evaluation of a bedside cardiac PET/SPECT system. The system was designed to move within a hospital to image critically-ill patients, for example, those in intensive care unit (ICU) or emergency room settings, who cannot easily be transported to a conventional SPECT or PET facility. The system uses two compact (25 cm times 25 cm) detectors with pixilated NaI crystals and position sensitive PMTs. The performance is evaluated for both 140 keV (Tc-99m) and 511 keV (F-18) emitters with the system operating in single photon counting (SPECT) mode. The imaging performance metrics for both 140 keV and 511 keV included intrinsic energy resolution, spatial resolution (intrinsic, system, and reconstructed SPECT), detection sensitivity, count rate capability, and uniformity. Results demonstrated an intrinsic energy resolution of 31% at 140 keV and 23% at 511 keV, a planar intrinsic spatial resolution of 5.6 mm full width half-maximum (FWHM) at 140 keV and 6.3 mm FWHM at 511 keV, and a sensitivity of 4.15 countsmiddotmuCi-1 ldr s-1 at 140 keV and 0.67 counts ldr muCi-1 ldr s-1 at 511 keV. To further the study, a SPECT acquisition using a dynamic cardiac phantom was performed, and the resulting reconstructed images are presented.

Performance Evaluation of a Bedside Cardiac SPECT System

DOE Office of Scientific and Technical Information (OSTI.GOV)

M.T. Studenski, D.R. Gilland, J.G. Parker, B. Hammond, S. Majewski, A.G. Weisenberger, V. Popov

This paper reports on the initial performance evaluation of a bedside cardiac PET/SPECT system. The system was designed to move within a hospital to image critically-ill patients, for example, those in intensive care unit (ICU) or emergency room settings, who cannot easily be transported to a conventional SPECT or PET facility. The system uses two compact (25 cm times 25 cm) detectors with pixilated NaI crystals and position sensitive PMTs. The performance is evaluated for both 140 keV (Tc-99m) and 511 keV (F-18) emitters with the system operating in single photon counting (SPECT) mode. The imaging performance metrics for bothmore » 140 keV and 511 keV included intrinsic energy resolution, spatial resolution (intrinsic, system, and reconstructed SPECT), detection sensitivity, count rate capability, and uniformity. Results demonstrated an intrinsic energy resolution of 31% at 140 keV and 23% at 511 keV, a planar intrinsic spatial resolution of 5.6 mm full width half-maximum (FWHM) at 140 keV and 6.3 mm FWHM at 511 keV, and a sensitivity of 4.15 countsmiddotmuCi-1 ldr s-1 at 140 keV and 0.67 counts ldr muCi-1 ldr s-1 at 511 keV. To further the study, a SPECT acquisition using a dynamic cardiac phantom was performed, and the resulting reconstructed images are presented.« less

Lidar observation of transition of cirrus clouds over a tropical station Gadanki (13.45° N, 79.18° E): case studies

NASA Astrophysics Data System (ADS)

Srinivasan, M. A.; Rao, C. Dhananjaya; Krishnaiah, M.

2016-05-01

The present study describes Mie lidar observations of the cirrus cloud passage showing transition between double thin layers into single thick and single thick layer into double thin layers of cirrus over Gadanki region. During Case1: 17 January 2007, Case4: 12 June 2007, Case5: 14 July 2007 and Case6: 24 July 2007 the transition is found to from two thin cirrus layers into single geometrically thick layer. Case2: 14 May 2007 and Case3: 15 May 2007, the transition is found to from single geometrically thick layer into two thin cirrus layers. Linear Depolarization Ratio (LDR) and Back Scatter Ration (BSR) are found to show similar variation with strong peaks during transition; both LDR and Cloud Optical Depth (COD) is found to show similar variation except during transition with strong peaks in COD which is not clearly found from LDR for the all cases. There is a significant weakening of zonal and meridional winds during Case1 which might be due to the transition from multiple to single thick cirrus indicating potential capability of thick cirrus in modulating the wind fields. There exists strong upward wind dominance contributed to significant ascent in cloud-base altitude thereby causing transition of multiple thin layers into single thick cirrus.

Spatial differences between stars and brown dwarfs: a dynamical origin?

NASA Astrophysics Data System (ADS)

Parker, Richard J.; Andersen, Morten

2014-06-01

We use N-body simulations to compare the evolution of spatial distributions of stars and brown dwarfs in young star-forming regions. We use three different diagnostics: the ratio of stars to brown dwarfs as a function of distance from the region's centre, {R}_SSR, the local surface density of stars compared to brown dwarfs, ΣLDR, and we compare the global spatial distributions using the ΛMSR method. From a suite of 20 initially statistically identical simulations, 6/20 attain {R}_SSR ≪ 1 and ΣLDR ≪ 1 and ΛMSR ≪ 1, indicating that dynamical interactions could be responsible for observed differences in the spatial distributions of stars and brown dwarfs in star-forming regions. However, many simulations also display apparently contradictory results - for example, in some cases the brown dwarfs have much lower local densities than stars (ΣLDR ≪ 1), but their global spatial distributions are indistinguishable (ΛMSR = 1) and the relative proportion of stars and brown dwarfs remains constant across the region ({R}_SSR = 1). Our results suggest that extreme caution should be exercised when interpreting any observed difference in the spatial distribution of stars and brown dwarfs, and that a much larger observational sample of regions/clusters (with complete mass functions) is necessary to investigate whether or not brown dwarfs form through similar mechanisms to stars.

Near constant-time optimal piecewise LDR to HDR inverse tone mapping

NASA Astrophysics Data System (ADS)

Chen, Qian; Su, Guan-Ming; Yin, Peng

2015-02-01

In a backward compatible HDR image/video compression, it is a general approach to reconstruct HDR from compressed LDR as a prediction to original HDR, which is referred to as inverse tone mapping. Experimental results show that 2- piecewise 2nd order polynomial has the best mapping accuracy than 1 piece high order or 2-piecewise linear, but it is also the most time-consuming method because to find the optimal pivot point to split LDR range to 2 pieces requires exhaustive search. In this paper, we propose a fast algorithm that completes optimal 2-piecewise 2nd order polynomial inverse tone mapping in near constant time without quality degradation. We observe that in least square solution, each entry in the intermediate matrix can be written as the sum of some basic terms, which can be pre-calculated into look-up tables. Since solving the matrix becomes looking up values in tables, computation time barely differs regardless of the number of points searched. Hence, we can carry out the most thorough pivot point search to find the optimal pivot that minimizes MSE in near constant time. Experiment shows that our proposed method achieves the same PSNR performance while saving 60 times computation time compared to the traditional exhaustive search in 2-piecewise 2nd order polynomial inverse tone mapping with continuous constraint.

Color transfer between high-dynamic-range images

NASA Astrophysics Data System (ADS)

Hristova, Hristina; Cozot, Rémi; Le Meur, Olivier; Bouatouch, Kadi

2015-09-01

Color transfer methods alter the look of a source image with regards to a reference image. So far, the proposed color transfer methods have been limited to low-dynamic-range (LDR) images. Unlike LDR images, which are display-dependent, high-dynamic-range (HDR) images contain real physical values of the world luminance and are able to capture high luminance variations and finest details of real world scenes. Therefore, there exists a strong discrepancy between the two types of images. In this paper, we bridge the gap between the color transfer domain and the HDR imagery by introducing HDR extensions to LDR color transfer methods. We tackle the main issues of applying a color transfer between two HDR images. First, to address the nature of light and color distributions in the context of HDR imagery, we carry out modifications of traditional color spaces. Furthermore, we ensure high precision in the quantization of the dynamic range for histogram computations. As image clustering (based on light and colors) proved to be an important aspect of color transfer, we analyze it and adapt it to the HDR domain. Our framework has been applied to several state-of-the-art color transfer methods. Qualitative experiments have shown that results obtained with the proposed adaptation approach exhibit less artifacts and are visually more pleasing than results obtained when straightforwardly applying existing color transfer methods to HDR images.

Human Powered Vehicles in Support of Light Infantry Operations

DTIC Science & Technology

1989-06-02

company is that of the Company RTO page 17 Figure 6 1-9 INF SOP: Load Weights Dy Duty Position Source: 1-9 Standard operating Procedures, Oct 87...LOAD CO HQS WPEZAýLmo BASIC WINTER SPRING CO CDR 18.6 68.2 79.9 69.3 X0 15.4 65.0 76.7 66.1 1SG 13.5 63.1 74.8 64.2 SNIPER 17.3 66.9 78.6 68.0 CO RTO ...RIFLEMAN 22.2 71.8 83.5 72.9 PLT RTO 33.5 83.1 94.8 84.2 60mm MORTAR SEC LDR 24.5 74.1 85.8 75.2 SQD LDR 34.0 83.6 95.3 84.7 GUNNER 22.7 72.3 84.0 73.4 AG

ColorChecker at the beach: dangers of sunburn and glare

NASA Astrophysics Data System (ADS)

McCann, John

2014-01-01

In High-Dynamic-Range (HDR) imaging, optical veiling glare sets the limits of accurate scene information recorded by a camera. But, what happens at the beach? Here we have a Low-Dynamic-Range (LDR) scene with maximal glare. Can we calibrate a camera at the beach and not be burnt? We know that we need sunscreen and sunglasses, but what about our cameras? The effect of veiling glare is scene-dependent. When we compare RAW camera digits with spotmeter measurements we find significant differences. As well, these differences vary, depending on where we aim the camera. When we calibrate our camera at the beach we get data that is valid for only that part of that scene. Camera veiling glare is an issue in LDR scenes in uniform illumination with a shaded lens.

VHITAL-160 Thruster Development Status

NASA Technical Reports Server (NTRS)

Sengupta, Anita; Marrese-Reading, Colleen; Hofer, Rich; Owens, Al; Swindlehurst, Ray; Fitzgerald, Dennis

2006-01-01

A general overview on the status of the Very High Isp Thruster with Anode Layer (VHITAL)-160 program is presented. The topics include: 1) Bi TAL Overview; 2) VHITAL Program Overview; 3) Thruster Fabrication; and 4) Thruster Testing.

Individuals with Disabilities Education Act: Reauthorization Overview. CRS Report for Congress.

ERIC Educational Resources Information Center

Aleman, Steven R.

This report provides an overview of programs authorized under the Individuals with Disabilities Education Act (IDEA) and discusses potential reauthorization issues. Programs include the Grants to States program, preschool program, infants and toddlers program, and discretionary grant programs. For each program, information includes fiscal year…

Crew-integration and Automation Testbed (CAT)Program Overview and RUX06 Introduction

DTIC Science & Technology

2006-09-20

unlimited Crew-integration and Automation Testbed ( CAT ) Program Overview and RUX06 Introduction 26-27 July 2006 Patrick Nunez, Terry Tierney, Brian Novak...3. DATES COVERED 4. TITLE AND SUBTITLE Crew-integration and Automation Testbed ( CAT )Program Overview and RUX06 Introduction 5a. CONTRACT...Experiment • Capstone CAT experiment – Evaluate effectiveness of CAT program in improving the performance and/or reducing the workload for a mounted

Context-dependent JPEG backward-compatible high-dynamic range image compression

NASA Astrophysics Data System (ADS)

Korshunov, Pavel; Ebrahimi, Touradj

2013-10-01

High-dynamic range (HDR) imaging is expected, together with ultrahigh definition and high-frame rate video, to become a technology that may change photo, TV, and film industries. Many cameras and displays capable of capturing and rendering both HDR images and video are already available in the market. The popularity and full-public adoption of HDR content is, however, hindered by the lack of standards in evaluation of quality, file formats, and compression, as well as large legacy base of low-dynamic range (LDR) displays that are unable to render HDR. To facilitate the wide spread of HDR usage, the backward compatibility of HDR with commonly used legacy technologies for storage, rendering, and compression of video and images are necessary. Although many tone-mapping algorithms are developed for generating viewable LDR content from HDR, there is no consensus of which algorithm to use and under which conditions. We, via a series of subjective evaluations, demonstrate the dependency of the perceptual quality of the tone-mapped LDR images on the context: environmental factors, display parameters, and image content itself. Based on the results of subjective tests, it proposes to extend JPEG file format, the most popular image format, in a backward compatible manner to deal with HDR images also. An architecture to achieve such backward compatibility with JPEG is proposed. A simple implementation of lossy compression demonstrates the efficiency of the proposed architecture compared with the state-of-the-art HDR image compression.

Comparisons between different techniques for measuring mass segregation

NASA Astrophysics Data System (ADS)

Parker, Richard J.; Goodwin, Simon P.

2015-06-01

We examine the performance of four different methods which are used to measure mass segregation in star-forming regions: the radial variation of the mass function {M}_MF; the minimum spanning tree-based ΛMSR method; the local surface density ΣLDR method; and the ΩGSR technique, which isolates groups of stars and determines whether the most massive star in each group is more centrally concentrated than the average star. All four methods have been proposed in the literature as techniques for quantifying mass segregation, yet they routinely produce contradictory results as they do not all measure the same thing. We apply each method to synthetic star-forming regions to determine when and why they have shortcomings. When a star-forming region is smooth and centrally concentrated, all four methods correctly identify mass segregation when it is present. However, if the region is spatially substructured, the ΩGSR method fails because it arbitrarily defines groups in the hierarchical distribution, and usually discards positional information for many of the most massive stars in the region. We also show that the ΛMSR and ΣLDR methods can sometimes produce apparently contradictory results, because they use different definitions of mass segregation. We conclude that only ΛMSR measures mass segregation in the classical sense (without the need for defining the centre of the region), although ΣLDR does place limits on the amount of previous dynamical evolution in a star-forming region.

Low-dose radiotherapy as a chemo-potentiator of a chemotherapy regimen with pemetrexed for recurrent non-small-cell lung cancer: a prospective phase II study.

PubMed

Mantini, Giovanna; Valentini, Vincenzo; Meduri, Bruno; Margaritora, Stefano; Balducci, Mario; Micciché, Francesco; Nardone, Luigia; De Rose, Fiorenza; Cesario, Alfredo; Larici, Anna Rita; Maggi, Fabio; Calcagni, Maria Lucia; Granone, Pierluigi

2012-11-01

Low-dose radiotherapy (LDR) (<50 cGy) induces enhanced cell killing in vitro via the hyper-radiation sensitivity phenomenon. Aim of this study was to evaluate the safety and efficacy of a palliative regimen combining pemetrexed and LDR (as a chemopotentiator) on patients affected by recurrent non-small-cell lung cancer (NSCLC). Eligible patients had an ECOG performance status ≤2, one prior chemotherapy regimen for advanced NSCLC, adequate organ function, measurable lesions. Patients received pemetrexed (500 mg/m(2) IV) and concurrent LDR (40 cGy bid on days 1 and 2) delivered to target pulmonary or metastatic disease. This cycle was repeated fourfold every 21 days. The accrual was determined by the single proportion powered analysis (α=0.05, power=0.8) with H0 ("bad" response probability, 9% according to literature) and H1 ("good" response probability, 35% ongoing study); 19 is the number required. Nineteen patients with stage III and IV disease were enrolled. Only one patient experienced neutropenia grade 4. All patients are evaluable for clinical response of irradiated lesion: overall response rate was 42%. Low-dose radiotherapy combined with pemetrexed has a similar toxicity profile to chemotherapy alone. The response rate of this novel approach is encouraging, since it was higher than what was reported for pemetrexed alone (42% versus 9.1%). Additional scientific investigation of this new treatment paradigm is warranted. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Analysis of La Dehesa paleo-landslide. Central Pre-Andes of Argentina

NASA Astrophysics Data System (ADS)

Tapia Baldis, Carla; Rothis, Luis Martín; Perucca, Laura; Esper Angillieri, María; Vargas, Horacio; Ponce, David; Allis, Carlos

2018-04-01

The main objective of this paper is to consider the influence of Quaternary faults as likely triggering factor for rockslides occurrence in the Central Pre-Andes, a region with intense shallow seismic activity. A rockslide deposit was selected as study case, placed in the western flank of La Dehesa and Talacasto (DT) range (31°3‧37″ S and 68°46‧ 8″ W). Applied methodology includes the characterization of main discontinuities, reconstruction of the topography using a high-resolution digital elevation model, safety factor calculation along the sliding surface and, Newmark displacements estimation for three different hypothetical seismic scenarios, recreated from existing neotectonic local information. Equilibrium-limit method's results confirm that study case, La Dehesa rockslide (LDR), had a stable and safe slope's configuration under static conditions. However, a seismic horizontal coefficient between 0.2 and 0.3 decreases safety factor below the safety threshold. Newmark's displacements for different seismic reconstructed scenarios varies between 4.1 and 15.9 cm, values that agreed with a coherent failure process, likely triggered by Pleistocene to Holocene seismogenic sources in Central Pre-Andes. LDR trigger could be assigned mainly to an earthquake related to La Dehesa Quaternary fault (LDF) activity; however, similar movements produced by neighboring faults should not be discarded. LDR triggering related to climatic conditions is despised. Finally, the methodology presented in this work is easy to reproduce and may be applied to other rockslides located in the mountainous areas of the Central Pre-Andes of Argentina.

The DEEP-South: Scheduling and Data Reduction Software System

NASA Astrophysics Data System (ADS)

Yim, Hong-Suh; Kim, Myung-Jin; Bae, Youngho; Moon, Hong-Kyu; Choi, Young-Jun; Roh, Dong-Goo; the DEEP-South Team

2015-08-01

The DEep Ecliptic Patrol of the Southern sky (DEEP-South), started in October 2012, is currently in test runs with the first Korea Microlensing Telescope Network (KMTNet) 1.6 m wide-field telescope located at CTIO in Chile. While the primary objective for the DEEP-South is physical characterization of small bodies in the Solar System, it is expected to discover a large number of such bodies, many of them previously unknown.An automatic observation planning and data reduction software subsystem called "The DEEP-South Scheduling and Data reduction System" (the DEEP-South SDS) is currently being designed and implemented for observation planning, data reduction and analysis of huge amount of data with minimum human interaction. The DEEP-South SDS consists of three software subsystems: the DEEP-South Scheduling System (DSS), the Local Data Reduction System (LDR), and the Main Data Reduction System (MDR). The DSS manages observation targets, makes decision on target priority and observation methods, schedules nightly observations, and archive data using the Database Management System (DBMS). The LDR is designed to detect moving objects from CCD images, while the MDR conducts photometry and reconstructs lightcurves. Based on analysis made at the LDR and the MDR, the DSS schedules follow-up observation to be conducted at other KMTNet stations. In the end of 2015, we expect the DEEP-South SDS to achieve a stable operation. We also have a plan to improve the SDS to accomplish finely tuned observation strategy and more efficient data reduction in 2016.

Potential effects of the invasive species Gracilaria vermiculophylla on Zostera marina metabolism and survival.

PubMed

Martínez-Lüscher, Johann; Holmer, Marianne

2010-06-01

The potential threat to seagrasses of the invasive algae, Gracilaria vermiculophylla was assessed through metabolic indicators under experimental conditions. Net leaf photosynthesis (LNP) and dark respiration (LDR) were measured from leaf segments of Zostera marina shoots under different loads of G. vermiculophylla (control, low 2.2kg FW m(-2) and high 4kg FW m(-2)) in mesocosm experiments separated in tanks at four temperatures (19, 23.5, 26 and 30 degrees C). LNP decreased in the presence of the high density G. vermiculophylla mat (25% on average), being the most severe reductions at 30 degrees C (35% less in high). LDR did not respond significantly to differences in algal biomass, whereas a progressive increase was found with increasing temperatures (3.4 times higher at 30 degrees C than at 19 degrees C). Sulphide in porewater was measured weekly in order clarify the role of sediment conditions on seagrass metabolism, and increased both with algal biomass (29% in high) and temperature (from 0.5mM at 26 degrees C to 2.6mM at 30 degrees C), but changes in LNP and LDR were not correlated with sulphide concentrations. Seagrass survival rates showed decreasing trend with algal biomass at all the temperatures (from 74% to 21% survival). G. vermiculophylla showed harmful effects on Z. marina metabolism and survival with synergistic effects of temperature suggesting greater impact of invasive species under future higher water temperatures.

Superfluid helium on orbit transfer (SHOOT)

NASA Technical Reports Server (NTRS)

Dipirro, Michael J.

1987-01-01

A number of space flight experiments and entire facilities require superfluid helium as a coolant. Among these are the Space Infrared Telescope Facility (SIRTF), the Large Deployable Reflector (LDR), the Advanced X-ray Astrophysics Facility (AXAF), the Particle Astrophysics Magnet Facility (PAMF or Astromag), and perhaps even a future Hubble Space Telescope (HST) instrument. Because these systems are required to have long operational lifetimes, a means to replenish the liquid helium, which is exhausted in the cooling process, is required. The most efficient method of replenishment is to refill the helium dewars on orbit with superfluid helium (liquid helium below 2.17 Kelvin). To develop and prove the technology required for this liquid helium refill, a program of ground and flight testing was begun. The flight demonstration is baselined as a two flight program. The first, described in this paper, will prove the concepts involved at both the component and system level. The second flight will demonstrate active astronaut involvement and semi-automated operation. The current target date for the first launch is early 1991.

Land Remote Sensing Overview

NASA Technical Reports Server (NTRS)

Byrnes, Ray

2007-01-01

A general overview of the USGS land remote sensing program is presented. The contents include: 1) Brief overview of USGS land remote sensing program; 2) Highlights of JACIE work at USGS; 3) Update on NASA/USGS Landsat Data Continuity Mission; and 4) Notes on alternative data sources.

X-43A Project Overview: Adventures in Hypersonics

NASA Technical Reports Server (NTRS)

Davis, Mark

2007-01-01

This viewgraph presentation gives a general overview of the X-43A program. The contents include: 1) X-43A Program Overview; 2) Vehicle Description; 3) Flight 1, MIB & Return to Flight; 4) Flight 2 and Results; and 5) Flight 3 and Results.

Green Power Partnership Program Overview

EPA Pesticide Factsheets

The U.S. EPA's Green Power Partnership is a voluntary program designed to reduce the environmental impact of electricity generation by promoting renewable energy. This page provides a brief program overview, including vision and accomplishments.

Uncertainties of parameterized surface downward clear-sky shortwave and all-sky longwave radiation.

NASA Astrophysics Data System (ADS)

Gubler, S.; Gruber, S.; Purves, R. S.

2012-06-01

As many environmental models rely on simulating the energy balance at the Earth's surface based on parameterized radiative fluxes, knowledge of the inherent model uncertainties is important. In this study we evaluate one parameterization of clear-sky direct, diffuse and global shortwave downward radiation (SDR) and diverse parameterizations of clear-sky and all-sky longwave downward radiation (LDR). In a first step, SDR is estimated based on measured input variables and estimated atmospheric parameters for hourly time steps during the years 1996 to 2008. Model behaviour is validated using the high quality measurements of six Alpine Surface Radiation Budget (ASRB) stations in Switzerland covering different elevations, and measurements of the Swiss Alpine Climate Radiation Monitoring network (SACRaM) in Payerne. In a next step, twelve clear-sky LDR parameterizations are calibrated using the ASRB measurements. One of the best performing parameterizations is elected to estimate all-sky LDR, where cloud transmissivity is estimated using measured and modeled global SDR during daytime. In a last step, the performance of several interpolation methods is evaluated to determine the cloud transmissivity in the night. We show that clear-sky direct, diffuse and global SDR is adequately represented by the model when using measurements of the atmospheric parameters precipitable water and aerosol content at Payerne. If the atmospheric parameters are estimated and used as a fix value, the relative mean bias deviance (MBD) and the relative root mean squared deviance (RMSD) of the clear-sky global SDR scatter between between -2 and 5%, and 7 and 13% within the six locations. The small errors in clear-sky global SDR can be attributed to compensating effects of modeled direct and diffuse SDR since an overestimation of aerosol content in the atmosphere results in underestimating the direct, but overestimating the diffuse SDR. Calibration of LDR parameterizations to local conditions reduces MBD and RMSD strongly compared to using the published values of the parameters, resulting in relative MBD and RMSD of less than 5% respectively 10% for the best parameterizations. The best results to estimate cloud transmissivity during nighttime were obtained by linearly interpolating the average of the cloud transmissivity of the four hours of the preceeding afternoon and the following morning. Model uncertainty can be caused by different errors such as code implementation, errors in input data and in estimated parameters, etc. The influence of the latter (errors in input data and model parameter uncertainty) on model outputs is determined using Monte Carlo. Model uncertainty is provided as the relative standard deviation σrel of the simulated frequency distributions of the model outputs. An optimistic estimate of the relative uncertainty σrel resulted in 10% for the clear-sky direct, 30% for diffuse, 3% for global SDR, and 3% for the fitted all-sky LDR.

Introduction to Metagenomics at DOE JGI: Program Overview and Program Informatics (Metagenomics Informatics Challenges Workshop: 10K Genomes at a Time)

ScienceCinema

Tringe, Susannah

2018-01-15

Susannah Tringe of the DOE Joint Genome Institute talks about the Program Overview and Program Informatics at the Metagenomics Informatics Challenges Workshop held at the DOE JGI on October 12-13, 2011.

76 FR 7175 - Native Hawaiian Education Program; Office of Elementary and Secondary Education; Overview...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-09

... DEPARTMENT OF EDUCATION Native Hawaiian Education Program; Office of Elementary and Secondary Education; Overview Information; Native Hawaiian Education Program; Notice Inviting Applications for New... Hawaiian Education (NHE) program is to support innovative projects that enhance the educational services...

ATP Interior Noise Technology and Flight Demonstration Program

NASA Technical Reports Server (NTRS)

Stephens, David G.; Powell, Clemans A.

1988-01-01

The paper provides an overview of the ATP (Advanced Turboprop Program) acoustics program with emphasis on the NASA technology program and the recent NASA/Industry demonstration programs aimed at understanding and controlling passenger cabin noise. Technology developments in propeller (source) noise, cabin noise transmission, and subjective acoustics are described. Finally, an overview of the industry demonstrator programs is presented.

Family Support Programs and Incarcerated Parents: Overview of Family Support Programs.

ERIC Educational Resources Information Center

Family Resource Coalition, Chicago, IL.

This fact sheet begins with an overview of family support programs, which includes a discussion of the premises of family support programs and a list of typical program components. The remainder of the fact sheet focuses on support programs for incarcerated parents. The children of incarcerated parents, though innocent of any crime, are often…

Calculation of Hazardous Waste Land Disposal Restrictions (LDR) Treatment Standards

EPA Pesticide Factsheets

examples of calculations of treatment standards including for High Concentration Selenium Wastes Using Data Submitted by Chemical Waste Management (CWM) and Antimony Using Data Submitted by Chemical Waste Management and Data Obtained From Rollins.

13 CFR 313.3 - Overview of Community Trade Adjustment Assistance.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 13 Business Credit and Assistance 1 2013-01-01 2013-01-01 false Overview of Community Trade..., DEPARTMENT OF COMMERCE COMMUNITY TRADE ADJUSTMENT ASSISTANCE Participation in the Community Trade Adjustment Assistance Program § 313.3 Overview of Community Trade Adjustment Assistance. The Community TAA Program is...

13 CFR 313.3 - Overview of Community Trade Adjustment Assistance.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 13 Business Credit and Assistance 1 2014-01-01 2014-01-01 false Overview of Community Trade..., DEPARTMENT OF COMMERCE COMMUNITY TRADE ADJUSTMENT ASSISTANCE Participation in the Community Trade Adjustment Assistance Program § 313.3 Overview of Community Trade Adjustment Assistance. The Community TAA Program is...

Using gas chromatography with ion mobility spectrometry to resolve explosive compounds in the presence of interferents.

PubMed

Cook, Greg W; LaPuma, Peter T; Hook, Gary L; Eckenrode, Brian A

2010-11-01

Ion mobility spectrometry (IMS) is a valued field detection technology because of its speed and high sensitivity, but IMS cannot easily resolve analytes of interest within mixtures. Coupling gas chromatography (GC) to IMS adds a separation capability to resolve complex matrices. A GC-IONSCAN® operated in IMS and GC⁄ IMS modes was evaluated with combinations of five explosives and four interferents. In 100 explosive/interferent combinations, IMS yielded 21 false positives while GC⁄ IMS substantially reduced the occurrence of false positives to one. In addition, the results indicate that through redesign or modification of the preconcentrator there would be significant advantages to using GC⁄ IMS, such as enhancement of the linear dynamic range (LDR) in some situations. By balancing sensitivity with LDR, GC⁄ IMS could prove to be a very advantageous tool when addressing real world complex mixture situations.

System concept for a moderate cost Large Deployable Reflector (LDR)

NASA Technical Reports Server (NTRS)

Swanson, P. N.; Breckinridge, J. B.; Diner, A.; Freeland, R. E.; Irace, W. R.; Mcelroy, P. M.; Meinel, A. B.; Tolivar, A. F.

1986-01-01

A study was carried out at JPL during the first quarter of 1985 to develop a system concept for NASA's LDR. Major features of the concept are a four-mirror, two-stage optical system; a lightweight structural composite segmented primary reflector; and a deployable truss backup structure with integral thermal shield. The two-stage optics uses active figure control at the quaternary reflector located at the primary reflector exit pupil, allowing the large primary to be passive. The lightweight composite reflector panels limit the short-wavelength operation to approximately 30 microns but reduce the total primary reflector weight by a factor of 3 to 4 over competing technologies. On-orbit thermal analysis indicates a primary reflector equilibrium temperature of less than 200 K with a maximum gradient of about 5 C across the 20-m aperture. Weight and volume estimates are consistent with a single Shuttle launch, and are based on Space Station assembly and checkout.

Electron acoustic solitons in magneto-rotating electron-positron-ion plasma with nonthermal electrons and positrons

NASA Astrophysics Data System (ADS)

Jilani, K.; Mirza, Arshad M.; Iqbal, J.

2015-02-01

The propagation of electron acoustic solitary waves (EASWs) in a magneto-rotating electron-positron-ion (epi) plasma containing cold dynamical electrons, nonthermal electrons and positrons obeying Cairns' distribution have been explored in the stationary background of massive positive ions. Through the linear dispersion relation (LDR) the effects of nonthermal components, magnetic field and rotation have been analyzed, wherein, various limiting cases have been deduced from the LDR. For nonlinear analysis, Korteweg-de Vries (KdV) equation is obtained using the reductive perturbation technique. It is found that in the presence of nonthermal positrons both hump and dip type solitons appear to excite, the structural properties of these solitary waves change drastically with magneto-rotating effects. The present work may be employed to explore and to understand the formation of electron acoustic solitary structures in the space and laboratory plasmas with nonthermal electrons and positrons under magneto-rotating effects.

Effect of tone mapping operators on visual attention deployment

NASA Astrophysics Data System (ADS)

Narwaria, Manish; Perreira Da Silva, Matthieu; Le Callet, Patrick; Pepion, Romuald

2012-10-01

High Dynamic Range (HDR) images/videos require the use of a tone mapping operator (TMO) when visualized on Low Dynamic Range (LDR) displays. From an artistic intention point of view, TMOs are not necessarily transparent and might induce different behavior to view the content. In this paper, we investigate and quantify how TMOs modify visual attention (VA). To that end both objective and subjective tests in the form of eye-tracking experiments have been conducted on several still image content that have been processed by 11 different TMOs. Our studies confirm that TMOs can indeed modify human attention and fixation behavior significantly. Therefore our studies suggest that VA needs consideration for evaluating the overall perceptual impact of TMOs on HDR content. Since the existing studies so far have only considered the quality or aesthetic appeal angle, this study brings in a new perspective regarding the importance of VA in HDR content processing for visualization on LDR displays.

Enhancing the Linear Dynamic Range in Multi-Channel Single Photon Detector beyond 7OD

PubMed Central

Gudkov, Dmytro; Gudkov, George; Gorbovitski, Boris; Gorfinkel, Vera

2015-01-01

We present design, implementation, and characterization of a single photon detector based on 32-channel PMT sensor [model H7260-20, Hamamatsu]. The developed high speed electronics enables the photon counting with linear dynamic range (LDR) up to 108count/s per detector's channel. The experimental characterization and Monte-Carlo simulations showed that in the single photon counting mode the LDR of the PMT sensor is limited by (i) “photon” pulse width (current pulse) of 900ps and (ii) substantial decrease of amplitudes of current pulses for count rates exceeding 108 count/s. The multi-channel architecture of the detector and the developed firm/software allow further expansion of the dynamic range of the device by 32-fold by using appropriate beam shaping. The developed single photon counting detector was tested for the detection of fluorescence labeled microbeads in capillary flow. PMID:27087788

Automatic face recognition in HDR imaging

NASA Astrophysics Data System (ADS)

Pereira, Manuela; Moreno, Juan-Carlos; Proença, Hugo; Pinheiro, António M. G.

2014-05-01

The gaining popularity of the new High Dynamic Range (HDR) imaging systems is raising new privacy issues caused by the methods used for visualization. HDR images require tone mapping methods for an appropriate visualization on conventional and non-expensive LDR displays. These visualization methods might result in completely different visualization raising several issues on privacy intrusion. In fact, some visualization methods result in a perceptual recognition of the individuals, while others do not even show any identity. Although perceptual recognition might be possible, a natural question that can rise is how computer based recognition will perform using tone mapping generated images? In this paper, a study where automatic face recognition using sparse representation is tested with images that result from common tone mapping operators applied to HDR images. Its ability for the face identity recognition is described. Furthermore, typical LDR images are used for the face recognition training.

Regional traffic signal operations programs : an overview

DOT National Transportation Integrated Search

2009-10-01

This report provides an overview of practices related to developing and sustaining a Regional Traffic Signal Operations Program. The purpose for a Regional Traffic Signal Operations Program is to provide regional partners a formal framework to collec...

Regional traffic signal operations programs : an overview.

DOT National Transportation Integrated Search

2009-10-01

This report provides an overview of practices related to developing and sustaining a Regional Traffic Signal Operations : Program. The purpose for a Regional Traffic Signal Operations Program is to provide regional partners a formal framework to : co...

The NASA Geodynamics Program: An overview

NASA Technical Reports Server (NTRS)

1983-01-01

This NASA Geodynamics Program overview collectively examines the history, scientific basis, status, and results of the NASA Program and outlines plans for the next five to eight years. It is intended as an informative nontechnical discussion of geodynamics research.

Detection and Serotyping of Dengue Virus in Serum Samples by Multiplex Reverse Transcriptase PCR-Ligase Detection Reaction Assay▿ †

PubMed Central

Das, S.; Pingle, M. R.; Muñoz-Jordán, J.; Rundell, M. S.; Rondini, S.; Granger, K.; Chang, G.-J. J.; Kelly, E.; Spier, E. G.; Larone, D.; Spitzer, E.; Barany, F.; Golightly, L. M.

2008-01-01

The detection and successful typing of dengue virus (DENV) from patients with suspected dengue fever is important both for the diagnosis of the disease and for the implementation of epidemiologic control measures. A technique for the multiplex detection and typing of DENV serotypes 1 to 4 (DENV-1 to DENV-4) from clinical samples by PCR-ligase detection reaction (LDR) has been developed. A serotype-specific PCR amplifies the regions of genes C and E simultaneously. The two amplicons are targeted in a multiplex LDR, and the resultant fluorescently labeled ligation products are detected on a universal array. The assay was optimized using 38 DENV strains and was evaluated with 350 archived acute-phase serum samples. The sensitivity of the assay was 98.7%, and its specificity was 98.4%, relative to the results of real-time PCR. The detection threshold was 0.017 PFU for DENV-1, 0.004 PFU for DENV-2, 0.8 PFU for DENV-3, and 0.7 PFU for DENV-4. The assay is specific; it does not cross-react with the other flaviviruses tested (West Nile virus, St. Louis encephalitis virus, Japanese encephalitis virus, Kunjin virus, Murray Valley virus, Powassan virus, and yellow fever virus). All but 1 of 26 genotypic variants of DENV serotypes in a global DENV panel from different geographic regions were successfully identified. The PCR-LDR assay is a rapid, sensitive, specific, and high-throughput technique for the simultaneous detection of all four serotypes of DENV. PMID:18685000

Evaluation of the effect of prostate volume change on tumor control probability in LDR brachytherapy.

PubMed

Knaup, Courtney; Mavroidis, Panayiotis; Stathakis, Sotirios; Smith, Mark; Swanson, Gregory; Papanikolaou, Niko

2011-09-01

This study evaluates low dose-rate brachytherapy (LDR) prostate plans to determine the biological effect of dose degradation due to prostate volume changes. In this study, 39 patients were evaluated. Pre-implant prostate volume was determined using ultrasound. These images were used with the treatment planning system (Nucletron Spot Pro 3.1(®)) to create treatment plans using (103)Pd seeds. Following the implant, patients were imaged using CT for post-implant dosimetry. From the pre and post-implant DVHs, the biologically equivalent dose and the tumor control probability (TCP) were determined using the biologically effective uniform dose. The model used RBE = 1.75 and α/β = 2 Gy. The prostate volume changed between pre and post implant image sets ranged from -8% to 110%. TCP and the mean dose were reduced up to 21% and 56%, respectively. TCP is observed to decrease as the mean dose decreases to the prostate. The post-implant tumor dose was generally observed to decrease, compared to the planned dose. A critical uniform dose of 130 Gy was established. Below this dose, TCP begins to fall-off. It was also determined that patients with a small prostates were more likely to suffer TCP decrease. The biological effect of post operative prostate growth due to operative trauma in LDR was evaluated using the concept. The post-implant dose was lower than the planned dose due to an increase of prostate volume post-implant. A critical uniform dose of 130 Gy was determined, below which TCP begun to decline.

Low-Dose Radiation Activates Akt and Nrf2 in the Kidney of Diabetic Mice: A Potential Mechanism to Prevent Diabetic Nephropathy

PubMed Central

Xing, Xiao; Zhang, Chi; Shao, Minglong; Tong, Qingyue; Zhang, Guirong; Li, Cai; Cheng, Jie; Jin, Shunzi; Ma, Jisheng; Wang, Guanjun; Li, Xiaokun; Cai, Lu

2012-01-01

Repetitive exposure of diabetic mice to low-dose radiation (LDR) at 25 mGy could significantly attenuate diabetes-induced renal inflammation, oxidative damage, remodeling, and dysfunction, for which, however, the underlying mechanism remained unknown. The present study explored the effects of LDR on the expression and function of Akt and Nrf2 in the kidney of diabetic mice. C57BL/6J mice were used to induce type 1 diabetes with multiple low-dose streptozotocin. Diabetic and age-matched control mice were irradiated with whole body X-rays at either single 25 mGy and 75 mGy or accumulated 75 mGy (25 mGy daily for 3 days) and then sacrificed at 1–12 h for examining renal Akt phosphorylation and Nrf2 expression and function. We found that 75 mGy of X-rays can stimulate Akt signaling pathway and upregulate Nrf2 expression and function in diabetic kidneys; single exposure of 25 mGy did not, but three exposures to 25 mGy of X-rays could offer a similar effect as single exposure to 75 mGy on the stimulation of Akt phosphorylation and the upregulation of Nrf2 expression and transcription function. These results suggest that single 75 mGy or multiple 25 mGy of X-rays can stimulate Akt phosphorylation and upregulate Nrf2 expression and function, which may explain the prevention of LDR against the diabetic nephropathy mentioned above. PMID:23227273

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cheong, S-K; Kim, J

Purpose: The aim of the study is the application of a Failure Modes and Effects Analysis (FMEA) to access the risks for patients undergoing a Low Dose Rate (LDR) Prostate Brachytherapy Treatment. Methods: FMEA was applied to identify all the sub processes involved in the stages of identifying patient, source handling, treatment preparation, treatment delivery, and post treatment. These processes characterize the radiation treatment associated with LDR Prostate Brachytherapy. The potential failure modes together with their causes and effects were identified and ranked in order of their importance. Three indexes were assigned for each failure mode: the occurrence rating (O),more » the severity rating (S), and the detection rating (D). A ten-point scale was used to score each category, ten being the number indicating most severe, most frequent, and least detectable failure mode, respectively. The risk probability number (RPN) was calculated as a product of the three attributes: RPN = O X S x D. The analysis was carried out by a working group (WG) at UPMC. Results: The total of 56 failure modes were identified including 32 modes before the treatment, 13 modes during the treatment, and 11 modes after the treatment. In addition to the protocols already adopted in the clinical practice, the prioritized risk management will be implanted to the high risk procedures on the basis of RPN score. Conclusion: The effectiveness of the FMEA method was established. The FMEA methodology provides a structured and detailed assessment method for the risk analysis of the LDR Prostate Brachytherapy Procedure and can be applied to other radiation treatment modes.« less

Effects of radiation and vitamin C treatment on metronidazole genotoxicity in mice.

PubMed

Das Roy, Lopamudra; Giri, Sarbani; Singh, Supriya; Giri, Anirudha

2013-05-15

The impact of exposure to low dose radiation (LDR) on human health is not clear. Besides, cross adaptation or sensitization with pharmaceutical agents may modify the risk of LDR. In the present study, we analyzed the interaction of radiation and metronidazole (MTZ) in inducing chromosome aberration (CA) and micronucleus (MN) in the bone marrow cells of Balb/C mice in vivo. Further, we evaluated the efficacy of vitamin C to reduce MTZ induced genotoxicity. We found that 10, 20 and 40mg/kg of MTZ induced dose dependent increase in the frequency of CA (r=0.9923, P<0.01) as well as MN (r=0.9823, P<0.05) in polychromatic erythrocytes. However, MTZ did not affect the ratio of polychromatic erythrocytes to normochromatic erythrocytes indicating lack of cytotoxicity. Supplementation with vitamin C prior to MTZ treatment significantly reduced the frequency of CA (P<0.001) as well as MN (P<0.001). Radiation (0.5Gy) exposure prior to MTZ treatment produced a less than additive (for CA) to additive (for MN) effects. However, radiation exposure following MTZ treatment produced additive (for CA) and synergistic (for MN) effects. Further, vitamin C pre-treatment also reduced the genotoxicity indices following the combined treatment of MTZ and radiation. Our findings suggest that MTZ may sensitize bone marrow cells to radiation exposure and enhances genotoxicity. We recommend more studies on the interaction of LDR and marketed pharmaceuticals to minimize possible harmful outcomes through appropriate precautionary measures. Copyright © 2013 Elsevier B.V. All rights reserved.

Conservation and solar energy program: congressional budget request, FY 1982

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

1981-01-01

Funding summaries are presented for the Conservation and Solar Energy Program funding information and program overview on energy conservation (Volume 7 of 7, DOE/CR-0011/2) are included for the Buildings and Community Systems, Industrial, Transportation; State and Local, Multi-Sector, Energy Impact Assistance, and Residential/Commercial retrofit programs. Funding information and program overviews on solar technology (Volume 2 of 7, DOE/CR-011/2) are included for Active and Passive Solar Heating and Cooling, Photovoltaics Energy Systems, Solar Thermal Power Systems, Biomass Energy Systems, Wind Energy Conversion Systems, Ocean Systems, Solar International Activities, Solar Information Systems, SERI Facility, MX-RES, Program Direction, and Alcohol Fuels programs. Informationmore » and overviews on energy production, demonstration, and distribution (Volume 6 of 7, DOE/CR-0011/2) are given for the solar program. A funding summary and a program overview are included for electrochemical and physical and chemical storage systems as appearing in DOE/CR-0011/2, Volume 3 of 7. Relevant tabulated data from the FY 1981. Request to the Congress are presented for Supplementals, Rescissions, and Deferrals. (MCW)« less

40 CFR 266.210 - What definitions apply to this subpart?

Code of Federal Regulations, 2010 CFR

2010-07-01

... waste described in 40 CFR 261.3. Hazardous Waste means any material which is defined to be hazardous waste in accordance with 40 CFR 261.3, “Definition of Hazardous Waste.” Land Disposal Restriction (LDR...

STEP flight experiments Large Deployable Reflector (LDR) telescope

NASA Technical Reports Server (NTRS)

Runge, F. C.

1984-01-01

Flight testing plans for a large deployable infrared reflector telescope to be tested on a space platform are discussed. Subsystem parts, subassemblies, and whole assemblies are discussed. Assurance of operational deployability, rigidization, alignment, and serviceability will be sought.

A Mathematical Model for the Height of a Satellite.

ERIC Educational Resources Information Center

Thoemke, Sharon S.; And Others

1993-01-01

Emphasizes a real-world-problem situation using sine law and cosine law. Angles of elevation from two tracking stations located in the plane of the equator determine height of a satellite. Calculators or computers can be used. (LDR)

Guidance: Demonstrating Compliance with the Land Disposal Restrictions (LDR) Alternative Soil Treatment Standards

EPA Pesticide Factsheets

This guidance provides suggestions and perspectives on how members of the regulated community, states, and the public can demonstrate compliance with the alternative treatment standards for certain contaminated soils that will be land disposed.

Mercer County Community College Remedial Program Assessment, August 1988. Two Year Follow-Up of the Fall 1986 Cohort.

ERIC Educational Resources Information Center

Porter, Al

This assessment of New Jersey's Mercer County Community College's (MCCC's) remedial program provides a program overview, results of a two-year follow-up of fall 1986 remedial students, and comparative data from previous years. The program overview examines policies and procedures concerning placement criteria, exit standards, program acceptance,…

Effects of Continuous Gamma-Ray Exposure In Utero in B6C3F1 Mice on Gestation Day 18 and at 10 Weeks of Age.

PubMed

Gulay, K C M; Tanaka, I B; Komura, J; Tanaka, S

2018-04-01

Pregnant C57BL/6JJcl mice were exposed to γ rays at low dose rate (20 mGy/day, LDR) or medium dose rate (200 and 400 mGy/day, MDR) from gestation day (GD) 0-18 to total accumulated doses of 360, 3,600 and 7,200 mGy, respectively. An additional group of pregnant mice were acutely exposed to 2 Gy at high dose rate (HDR) of 0.77 Gy/min on GD 11. In experiment 1, fetuses collected via cesarean section on GD 18 were examined for external and skeletal abnormalities. While the results of LDR exposure (20 mGy/day) did not significantly differ from the nonirradiated controls in all parameters examined, MDR (200 and 400 mGy/day) and acute HDR (2 Gy) exposure caused growth retardation and significantly increased incidence of unossified bones. Increased incidence of external abnormalities was observed only in the acute HDR group. In experiment 2, the dams were allowed to give birth and the pups were clinically monitored and weighed periodically until 10 weeks of age when they were sacrificed and subjected to pathological examination. Pups exposed at MDRs of 200 and 400 mGy/dayand at acute HDR of 0.77 Gy/min had lower bodyweights from weaning (3 weeks) to 10 weeks of age except for females exposed to 400 mGy/day MDR. None of the pups exposed to an acute 2 Gy dose on GD 11 survived to 10 weeks of age. Histopathological changes were not significantly different between the nonirradiated control and the 20 mGy/day LDR groups. However, at both MDR exposures of 200 and 400 mGy/day. gonadal (testes and ovary) hypoplasia/atrophy was observed in all the 10-week-old pups. Our results show that in utero LDR exposure to 20 mGy/day for the entire gestation period did not cause any significant effect in pups when compared to the nonirradiated controls up to 10 weeks of age. However, pups exposed in utero to MDRs showed dose-related growth retardation with delayed ossifications (400 mGy/day) and gonadal hypoplasia/atrophy. These findings suggest that increased post-implantation loss in dams exposed at MDR is due to early embryonic deaths resulting in early resorption.

5 CFR 2638.701 - Overview.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Administrative Personnel OFFICE OF GOVERNMENT ETHICS GOVERNMENT ETHICS OFFICE OF GOVERNMENT ETHICS AND EXECUTIVE AGENCY ETHICS PROGRAM RESPONSIBILITIES Executive Agency Ethics Training Programs § 2638.701 Overview. Each agency must have an ethics training program to teach employees about ethics laws and rules and to...

5 CFR 2638.701 - Overview.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Administrative Personnel OFFICE OF GOVERNMENT ETHICS GOVERNMENT ETHICS OFFICE OF GOVERNMENT ETHICS AND EXECUTIVE AGENCY ETHICS PROGRAM RESPONSIBILITIES Executive Agency Ethics Training Programs § 2638.701 Overview. Each agency must have an ethics training program to teach employees about ethics laws and rules and to...

5 CFR 2638.701 - Overview.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Administrative Personnel OFFICE OF GOVERNMENT ETHICS GOVERNMENT ETHICS OFFICE OF GOVERNMENT ETHICS AND EXECUTIVE AGENCY ETHICS PROGRAM RESPONSIBILITIES Executive Agency Ethics Training Programs § 2638.701 Overview. Each agency must have an ethics training program to teach employees about ethics laws and rules and to...

5 CFR 2638.701 - Overview.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Administrative Personnel OFFICE OF GOVERNMENT ETHICS GOVERNMENT ETHICS OFFICE OF GOVERNMENT ETHICS AND EXECUTIVE AGENCY ETHICS PROGRAM RESPONSIBILITIES Executive Agency Ethics Training Programs § 2638.701 Overview. Each agency must have an ethics training program to teach employees about ethics laws and rules and to...

5 CFR 2638.701 - Overview.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Administrative Personnel OFFICE OF GOVERNMENT ETHICS GOVERNMENT ETHICS OFFICE OF GOVERNMENT ETHICS AND EXECUTIVE AGENCY ETHICS PROGRAM RESPONSIBILITIES Executive Agency Ethics Training Programs § 2638.701 Overview. Each agency must have an ethics training program to teach employees about ethics laws and rules and to...

78 FR 25426 - Fisheries of the Exclusive Economic Zone Off Alaska; American Fisheries Act, Amendment 80 Program...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-01

... Community Development Quota Program; Public Workshops AGENCY: National Marine Fisheries Service (NMFS... Development Quota (CDQ) Program. The workshops will address (1) The applicability of cost recovery fees... overview of the potential impacts of cost recovery programs, and (3) an overview of proposed regulatory...

Hazardous Waste Management System: Land Disposal Restrictions - Federal Register Notice, May 15, 1992

EPA Pesticide Factsheets

In response to the Proposed Rule on Land Disposal Restrictions (LDR) for Newly Listed Wastes and Hazardous Debris, EPA received numerous comments regarding the availability of treatment capacity for hazardous debris. EPA agrees with these comments.

40 CFR 35.3025 - Overview of State performance under delegation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... performance of a delegated State through an annual overview program, developed in accordance with procedures... year. (1) Priority objectives will include both program and management objectives. In developing the... OTHER FEDERAL ASSISTANCE STATE AND LOCAL ASSISTANCE Construction Grants Program Delegation to States...

Technology Program Management Model (TPMM) Overview

DTIC Science & Technology

2006-05-10

1 1 “Secure the High Ground” Jeff Craver Project Manager Space and Missile Defense Technical Center Jeff.Craver@US.Army.Mil ff r r r j t r i il...f i l t r ff. r r . r . il UNCLASSIFIED UNCLASSIFIED Technology Program Management Model (TPMM) Overview 05-10-2006 Report Documentation Page Form...DATES COVERED 00-00-2006 to 00-00-2006 4. TITLE AND SUBTITLE Technology Program Management Model (TPMM) Overview 5a. CONTRACT NUMBER 5b. GRANT

50 CFR 84.31 - An overview of the ranking criteria.

Code of Federal Regulations, 2010 CFR

2010-10-01

... (CONTINUED) FINANCIAL ASSISTANCE-WILDLIFE SPORT FISH RESTORATION PROGRAM NATIONAL COASTAL WETLANDS CONSERVATION GRANT PROGRAM Project Selection § 84.31 An overview of the ranking criteria. (a) The primary...

A Systematic Review of Life Skill Development through Sports Programs Serving Socially Vulnerable Youth

ERIC Educational Resources Information Center

Hermens, Niels; Super, Sabina; Verkooijen, Kirsten T.; Koelen, Maria A.

2017-01-01

Purpose: Despite the strong belief in sports programs as a setting in which socially vulnerable youth can develop life skills, no overview exists of life skill development in sports programs serving this youth group. Therefore, the present systematic review provides an overview of the evidence on life skill development in sports programs serving…

Digital electronic engine control F-15 overview

NASA Technical Reports Server (NTRS)

Kock, B.

1984-01-01

A flight test evaluation of the digital elctronic engine control (DEEC) system was conducted. An overview of the flight program is presented. The roles of the participating parties, the system, and the flight program objectives are described. The test program approach is discussed, and the engine performance benefits are summarized. A description of the follow-on programs is included.

Glenn Research Center Human Research Program: Overview

NASA Technical Reports Server (NTRS)

Nall, Marsha M.; Myers, Jerry G.

2013-01-01

The NASA-Glenn Research Centers Human Research Program office supports a wide range of technology development efforts aimed at enabling extended human presence in space. This presentation provides a brief overview of the historical successes, current 2013 activities and future projects of NASA-GRCs Human Research Program.

40 CFR Appendix Viii to Part 268 - LDR Effective Dates of Injected Prohibited Hazardous Wastes

Code of Federal Regulations, 2010 CFR

2010-07-01

... containing less than 1 percent total F001-F005 solvent constituents Aug. 8, 1990. D001 (except High TOC Ignitable Liquids Subcategory) c All Feb. 10, 1994. D001 (High TOC Ignitable Characteristic Liquids...

Extending the Regular Curriculum through Creative Problem Solving.

ERIC Educational Resources Information Center

Bohan, Harry; Bohan, Susan

1993-01-01

Uses ancient Egyptian numeration system in a new setting to extend the concepts of base, place value, and correspondence. Discusses similarities and differences between the Egyptian and decimal systems. Students are asked to propose changes to make the Egyptian system easier. (LDR)

Hazardous Waste Management System: Land Disposal Restrictions - Federal Register Notice, June 26, 1992

EPA Pesticide Factsheets

EPA is taking regulatory action to approve an extension of the Land Disposal Restrictions (LDR) effective date applicable to owners and operators of secondary lead smelters who are engaged in the reclamation of lead-bearing hazardous materials.

Special Consolidated Checklists for Land Disposal Restrictions (unchanged since 1992)

EPA Pesticide Factsheets

This checklist consolidates LDR rules from the first rule promulgated on November 7, 1986 through June 30, 1992, including the Third Third Scheduled wastes (i.e., from Revision Checklist 34 through Revision Checklist 106, 57 FR 28628, June 26, 1992).

Federal Energy Management Program Overview

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

Brochure offers an overview of the Federal Energy Management Program (FEMP), which provides agencies and organizations with the information, tools, and assistance they need to achieve their energy-related requirements and goals through specialized initiatives.

24 CFR 572.1 - Overview of HOPE 3.

Code of Federal Regulations, 2010 CFR

2010-04-01

... DEVELOPMENT COMMUNITY FACILITIES HOPE FOR HOMEOWNERSHIP OF SINGLE FAMILY HOMES PROGRAM (HOPE 3) General § 572.1 Overview of HOPE 3. The purpose of the HOPE for Homeownership of Single Family Homes program (HOPE... and implement homeownership programs designed to meet the needs of low-income first-time homebuyers...

STORM AND COMBINED SEWER OVERFLOW: AN OVERVIEW OF EPA'S RESEARCH PROGRAM (EPA/600/8-89/054)

EPA Science Inventory

This report represents an overview of the EPA's Storm & Combined Sewer Pollution Control Research Program performed over a 20-year period beginning with the mid-1960s. It covers program involvements in the development of a diverse technology including pollution-problem assessment...

Audiovisual Programming. Technology Learning Activity. Teacher Edition. Technology Education Series.

ERIC Educational Resources Information Center

Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

This packet of technology learning activity (TLA) materials on audiovisual programming for students in grades 6-10 consists of a technology education overview, information on use, and the instructor's and student's sections. The overview discusses the technology education program and materials. Components of the instructor's and student's sections…

Human Genome Program Report. Part 1, Overview and Progress

DOE R&D Accomplishments Database

1997-11-01

This report contains Part 1 of a two-part report to reflect research and progress in the U.S. Department of Energy Human Genome Program from 1994 through 1996, with specified updates made just before publication. Part 1 consists of the program overview and report on progress.

Human genome program report. Part 1, overview and progress

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1997-11-01

This report contains Part 1 of a two-part report to reflect research and progress in the U.S. Department of Energy Human Genome Program from 1994 through 1996, with specified updates made just before publication. Part 1 consists of the program overview and report on progress.

Determination of forest fuels characteristics in mortality-affected Pinus forests using integrated hyperspectral and ALS data

NASA Astrophysics Data System (ADS)

Romero Ramirez, Francisco J.; Navarro-Cerrillo, Rafael Mª.; Varo-Martínez, Mª. Ángeles; Quero, Jose Luis; Doerr, Stefan; Hernández-Clemente, Rocío

2018-06-01

Widespread tree mortality caused by forest decline in recent decades has raised concern among forest managers about how to assess forest fuels in these conditions. To investigate this question, we developed and tested an objective, consistent approach to the characterization of canopy fuel metrics - such as fuel load (FL), live fuel moisture content (LFMC), and live-dead ratio (LDR) - by integrating airborne laser scanning (ALS) and hyperspectral data to produce more-accurate estimates at the stand level. Regression models were developed for Pinus sylvestris and P. nigra stands representative of pine plantations in southern Spain, using field data acquired for different spatial fuel types and distributions as well as high resolution airborne hyperspectral data (AHS) and ALS datasets. Strong relationships were found between ALS and FL using a density of 2 points m-2 (R2 = 0.64) and between LFMC and Temperature/NDVI index at a spatial resolution of 5 m (R2 = 0.91). The red edge normalized index provided the highest separability (Jeffries-Matusita distance = 1.83) between types of LDR. The plot-aggregate ALS and AHS metrics performed better at spatial resolutions of 5 m and 2 points m-2 than at other scales. Cartography of the estimations of FL, LFMC, and LDR made using the empirical models from the ALS and AHS data showed a mean FL value of 65.87 Mg ha-1, an average LFMC content of 57.51%, and 30.75% of the surface classified as dead fuel (≥60% defoliation). The results suggest that our remote sensing approach could improve the estimation of canopy fuels characteristics at higher spatial resolutions as well as estimations of fuel cartography, to assist the planning and management of fuel reduction treatments.

Communicating Value in Health Care Using Radar Charts: A Case Study of Prostate Cancer.

PubMed

Thaker, Nikhil G; Ali, Tariq N; Porter, Michael E; Feeley, Thomas W; Kaplan, Robert S; Frank, Steven J

2016-09-01

The transformation from volume to value will require communication of outcomes and costs of therapies; however, outcomes are usually nonstandardized, and cost of therapy differs among stakeholders. We developed a standardized value framework by using radar charts to visualize and communicate a wide range of patient outcomes and cost for three forms of prostate cancer treatment. We retrospectively reviewed data from men with low-risk prostate cancer who were treated with low-dose rate brachytherapy (LDR-BT), proton beam therapy, or robotic-assisted prostatectomy. Patient-reported outcomes comprised the Expanded Prostate Cancer Index Composite-50 domains for sexual function, urinary incontinence and/or bother, bowel bother, and vitality 12 months after treatment. Costs were measured by time-driven activity-based costing for the first 12 months of the care cycle. Outcome and cost data were plotted on a single radar chart for each treatment modality. Outcome and cost data from patients who were treated with robotic-assisted prostatectomy (n = 381), proton beam therapy (n = 165), and LDR-BT (n = 238) were incorporated into the radar chart. LDR-BT seemed to deliver the highest overall value of the three treatment modalities; however, incorporation of patient preferences regarding outcomes may allow other modalities to be considered high-value treatment options. Standardization and visualization of outcome and cost metrics may allow more comprehensive and collaborative discussions about the value of health care services. Communicating the value framework by using radar charts may be an effective method to present total value and the value of all outcomes and costs in a manner that is accessible to all stakeholders. Variations in plotting of costs and outcomes will require future focus group initiatives. Copyright © 2016 by American Society of Clinical Oncology.

Communicating Value in Health Care Using Radar Charts: A Case Study of Prostate Cancer

PubMed Central

Thaker, Nikhil G.; Ali, Tariq N.; Porter, Michael E.; Feeley, Thomas W.; Kaplan, Robert S.

2016-01-01

Purpose: The transformation from volume to value will require communication of outcomes and costs of therapies; however, outcomes are usually nonstandardized, and cost of therapy differs among stakeholders. We developed a standardized value framework by using radar charts to visualize and communicate a wide range of patient outcomes and cost for three forms of prostate cancer treatment. Materials and Methods: We retrospectively reviewed data from men with low-risk prostate cancer who were treated with low-dose rate brachytherapy (LDR-BT), proton beam therapy, or robotic-assisted prostatectomy. Patient-reported outcomes comprised the Expanded Prostate Cancer Index Composite-50 domains for sexual function, urinary incontinence and/or bother, bowel bother, and vitality 12 months after treatment. Costs were measured by time-driven activity-based costing for the first 12 months of the care cycle. Outcome and cost data were plotted on a single radar chart for each treatment modality. Results: Outcome and cost data from patients who were treated with robotic-assisted prostatectomy (n = 381), proton beam therapy (n = 165), and LDR-BT (n = 238) were incorporated into the radar chart. LDR-BT seemed to deliver the highest overall value of the three treatment modalities; however, incorporation of patient preferences regarding outcomes may allow other modalities to be considered high-value treatment options. Conclusion: Standardization and visualization of outcome and cost metrics may allow more comprehensive and collaborative discussions about the value of health care services. Communicating the value framework by using radar charts may be an effective method to present total value and the value of all outcomes and costs in a manner that is accessible to all stakeholders. Variations in plotting of costs and outcomes will require future focus group initiatives. PMID:27577622

A study on the use of radar and lidar for characterizing ultragiant aerosol

NASA Astrophysics Data System (ADS)

Madonna, F.; Amodeo, A.; D'Amico, G.; Pappalardo, G.

2013-09-01

19 April to 19 May 2010, volcanic aerosol layers originating from the Eyjafjallajökull volcano were observed at the Institute of Methodologies for Environmental Analysis of the National Research Council of Italy Atmospheric Observatory, named CIAO (40.60°N, 15.72°E, 760 m above sea level), in Southern Italy with a multiwavelength Raman lidar. During this period, ultragiant aerosols were also observed at CIAO using a colocated 8.45 mm wavelength Doppler radar. The Ka-band radar signatures observed in four separate days (19 April and 7, 10, and 13 May) are consistent with the observation of nonspherical ultragiant aerosols characterized by values of linear depolarization ratio (LDR) higher than -4 dB. Air mass back trajectory analysis suggests a volcanic origin of the ultragiant aerosols observed by the radar. The observed values of the radar reflectivity (Ze) are consistent with a particle effective radius (r) larger than 50-75 µm. Scattering simulations based on the T-matrix approach show that the high LDR values can be explained if the observed particles have an absolute aspect ratio larger than 3.0 and consist of an internal aerosol core and external ice shell, with a variable radius ratio ranging between 0.2 and 0.7 depending on the shape and aspect ratio. Comparisons between daytime vertical profiles of aerosol backscatter coefficient (β) as measured by lidar and radar LDR reveal a decrease of β where ultragiant particles are observed. Scattering simulations based on Mie theory show how the lidar capability in typing ultragiant aerosols could be limited by low number concentrations or by the presence of an external ice shell covering the aerosol particles. Preferential vertical alignment of the particles is discussed as another possible reason for the decrease of β.

Development of an adjoint sensitivity field-based treatment-planning technique for the use of newly designed directional LDR sources in brachytherapy.

PubMed

Chaswal, V; Thomadsen, B R; Henderson, D L

2012-02-21

The development and application of an automated 3D greedy heuristic (GH) optimization algorithm utilizing the adjoint sensitivity fields for treatment planning to assess the advantage of directional interstitial prostate brachytherapy is presented. Directional and isotropic dose kernels generated using Monte Carlo simulations based on Best Industries model 2301 I-125 source are utilized for treatment planning. The newly developed GH algorithm is employed for optimization of the treatment plans for seven interstitial prostate brachytherapy cases using mixed sources (directional brachytherapy) and using only isotropic sources (conventional brachytherapy). All treatment plans resulted in V100 > 98% and D90 > 45 Gy for the target prostate region. For the urethra region, the D10(Ur), D90(Ur) and V150(Ur) and for the rectum region the V100cc, D2cc, D90(Re) and V90(Re) all are reduced significantly when mixed sources brachytherapy is used employing directional sources. The simulations demonstrated that the use of directional sources in the low dose-rate (LDR) brachytherapy of the prostate clearly benefits in sparing the urethra and the rectum sensitive structures from overdose. The time taken for a conventional treatment plan is less than three seconds, while the time taken for a mixed source treatment plan is less than nine seconds, as tested on an Intel Core2 Duo 2.2 GHz processor with 1GB RAM. The new 3D GH algorithm is successful in generating a feasible LDR brachytherapy treatment planning solution with an extra degree of freedom, i.e. directionality in very little time.

Design and optimization of a brachytherapy robot

NASA Astrophysics Data System (ADS)

Meltsner, Michael A.

Trans-rectal ultrasound guided (TRUS) low dose rate (LDR) interstitial brachytherapy has become a popular procedure for the treatment of prostate cancer, the most common type of non-skin cancer among men. The current TRUS technique of LDR implantation may result in less than ideal coverage of the tumor with increased risk of negative response such as rectal toxicity and urinary retention. This technique is limited by the skill of the physician performing the implant, the accuracy of needle localization, and the inherent weaknesses of the procedure itself. The treatment may require 100 or more sources and 25 needles, compounding the inaccuracy of the needle localization procedure. A robot designed for prostate brachytherapy may increase the accuracy of needle placement while minimizing the effect of physician technique in the TRUS procedure. Furthermore, a robot may improve associated toxicities by utilizing angled insertions and freeing implantations from constraints applied by the 0.5 cm-spaced template used in the TRUS method. Within our group, Lin et al. have designed a new type of LDR source. The "directional" source is a seed designed to be partially shielded. Thus, a directional, or anisotropic, source does not emit radiation in all directions. The source can be oriented to irradiate cancerous tissues while sparing normal ones. This type of source necessitates a new, highly accurate method for localization in 6 degrees of freedom. A robot is the best way to accomplish this task accurately. The following presentation of work describes the invention and optimization of a new prostate brachytherapy robot that fulfills these goals. Furthermore, some research has been dedicated to the use of the robot to perform needle insertion tasks (brachytherapy, biopsy, RF ablation, etc.) in nearly any other soft tissue in the body. This can be accomplished with the robot combined with automatic, magnetic tracking.

Development of an adjoint sensitivity field-based treatment-planning technique for the use of newly designed directional LDR sources in brachytherapy

NASA Astrophysics Data System (ADS)

Chaswal, V.; Thomadsen, B. R.; Henderson, D. L.

2012-02-01

The development and application of an automated 3D greedy heuristic (GH) optimization algorithm utilizing the adjoint sensitivity fields for treatment planning to assess the advantage of directional interstitial prostate brachytherapy is presented. Directional and isotropic dose kernels generated using Monte Carlo simulations based on Best Industries model 2301 I-125 source are utilized for treatment planning. The newly developed GH algorithm is employed for optimization of the treatment plans for seven interstitial prostate brachytherapy cases using mixed sources (directional brachytherapy) and using only isotropic sources (conventional brachytherapy). All treatment plans resulted in V100 > 98% and D90 > 45 Gy for the target prostate region. For the urethra region, the D10Ur, D90Ur and V150Ur and for the rectum region the V100cc, D2cc, D90Re and V90Re all are reduced significantly when mixed sources brachytherapy is used employing directional sources. The simulations demonstrated that the use of directional sources in the low dose-rate (LDR) brachytherapy of the prostate clearly benefits in sparing the urethra and the rectum sensitive structures from overdose. The time taken for a conventional treatment plan is less than three seconds, while the time taken for a mixed source treatment plan is less than nine seconds, as tested on an Intel Core2 Duo 2.2 GHz processor with 1GB RAM. The new 3D GH algorithm is successful in generating a feasible LDR brachytherapy treatment planning solution with an extra degree of freedom, i.e. directionality in very little time.

Institutional experience of interstitial brachytherapy for head and neck cancer with a comparison of high- and low dose rate practice.

PubMed

Mohanti, Bidhu Kalyan; Sahai, Puja; Thakar, Alok; Sikka, Kapil; Bhasker, Suman; Sharma, Atul; Sharma, Seema; Bahadur, Sudhir

2014-01-01

To describe our institutional experience with high dose rate (HDR) interstitial brachytherapy (IBT) compared with previously reported results on the low dose rate (LDR) practice for head and neck cancer. Eighty-four patients with oral cavity (n=70) or oropharyngeal cancer (n=14) were treated with 192Ir HDR-IBT. Seventy-eight patients had stage I or II tumour. The patients treated with IBT alone (n=42) received 39-42 Gy/10-14 fractions (median=40 Gy/10 fractions). With respect to the combination therapy group (n=42), prescription dose comprised of 12-18 Gy/3-6 fractions (median=15 Gy/5 fractions) for IBT and 40-50 Gy/20-25 fractions (median=50 Gy/25 fractions) for external radiotherapy. Brachytherapy was given as 2 fractions per day 6 hours apart with 4 Gy per fraction for monotherapy and 3 Gy per fraction for combination therapy. Four patients were not evaluable in the analysis of outcome. The primary site relapse rates were 23.8% (10/42) and 68.4% (26/38) in patients treated with IBT alone and combination therapy, respectively (p<0.001). Salvage surgery was performed in 19 patients. The 5-year local control rate was estimated at 62% and the disease-free survival (DFS) rate at 52% for all patients. Local control with respect to T1 and T2 tumours was 84% and 42%, respectively. Our present series on HDR-IBT and the previous report on LDR-IBT for head and neck cancer demonstrated similar DFS rates at 5 years (52%). The rate of regional failure in node-negative patients was <20% in both of our series. HDR-IBT offers similar results to LDR-IBT for head and neck cancer.

Topical ketoprofen nanogel: artificial neural network optimization, clustered bootstrap validation, and in vivo activity evaluation based on longitudinal dose response modeling.

PubMed

Elkomy, Mohammed H; Elmenshawe, Shahira F; Eid, Hussein M; Ali, Ahmed M A

2016-11-01

This work aimed at investigating the potential of solid lipid nanoparticles (SLN) as carriers for topical delivery of Ketoprofen (KP); evaluating a novel technique incorporating Artificial Neural Network (ANN) and clustered bootstrap for optimization of KP-loaded SLN (KP-SLN); and demonstrating a longitudinal dose response (LDR) modeling-based approach to compare the activity of topical non-steroidal anti-inflammatory drug formulations. KP-SLN was fabricated by a modified emulsion/solvent evaporation method. Box-Behnken design was implemented to study the influence of glycerylpalmitostearate-to-KP ratio, Tween 80, and lecithin concentrations on particle size, entrapment efficiency, and amount of drug permeated through rat skin in 24 hours. Following clustered bootstrap ANN optimization, the optimized KP-SLN was incorporated into an aqueous gel and evaluated for rheology, in vitro release, permeability, skin irritation and in vivo activity using carrageenan-induced rat paw edema model and LDR mathematical model to analyze the time course of anti-inflammatory effect at various application durations. Lipid-to-drug ratio of 7.85 [bootstrap 95%CI: 7.63-8.51], Tween 80 of 1.27% [bootstrap 95%CI: 0.601-2.40%], and Lecithin of 0.263% [bootstrap 95%CI: 0.263-0.328%] were predicted to produce optimal characteristics. Compared with profenid® gel, the optimized KP-SLN gel exhibited slower release, faster permeability, better texture properties, greater efficacy, and similar potency. SLNs are safe and effective permeation enhancers. ANN coupled with clustered bootstrap is a useful method for finding optimal solutions and estimating uncertainty associated with them. LDR models allow mechanistic understanding of comparative in vivo performances of different topical formulations, and help design efficient dermatological bioequivalence assessment methods.

Genome-wide screen of DNA methylation changes induced by low dose X-ray radiation in mice.

PubMed

Wang, Jingzi; Zhang, Youwei; Xu, Kai; Mao, Xiaobei; Xue, Lijun; Liu, Xiaobei; Yu, Hongjun; Chen, Longbang; Chu, Xiaoyuan

2014-01-01

Epigenetic mechanisms play a key role in non-targeted effects of radiation. The purpose of this study was to investigate global hypomethylation and promoter hypermethylation of particular genes induced by low dose radiation (LDR). Thirty male BALB/c mice were divided into 3 groups: control, acutely exposed (0.5 Gy X-rays), and chronic exposure for 10 days (0.05Gy/d×10d). High-performance liquid chromatography (HPLC) and MeDIP-quantitative polymerase chain reaction (qPCR) were used to study methylation profiles. DNMT1 and MBD2 expression was determined by qPCR and western blot assays. Methylation and expression of Rad23b and Ddit3 were determined by bisulfate sequencing primers (BSP) and qPCR, respectively. The results show that LDR induced genomic hypomethylation in blood 2 h postirraditaion, but was not retained at 1-month. DNMT1 and MBD2 were downregulated in a tissue-specific manner but did not persist. Specific hypermethylation was observed for 811 regions in the group receiving chronic exposure, which covered almost all key biological processes as indicated by GO and KEGG pathway analysis. Eight hypermethylated genes (Rad23b, Tdg, Ccnd1, Ddit3, Llgl1, Rasl11a, Tbx2, Scl6a15) were verified by MeDIP-qPCR. Among them, Rad23b and Ddit3 gene displayed tissue-specific methylation and downregulation, which persisted for 1-month postirradiation. Thus, LDR induced global hypomethylation and tissue-specific promoter hypermethylation of particular genes. Promoter hypermethylation, rather than global hypomethylation, was relatively stable. Dysregulation of methylation might be correlated with down-regulation of DNMT1 and MBD2, but much better understanding the molecular mechanisms involved in this process will require further study.

Zero-profile Anchored Spacer Reduces Rate of Dysphagia Compared With ACDF With Anterior Plating.

PubMed

Hofstetter, Christoph P; Kesavabhotla, Kartik; Boockvar, John A

2015-06-01

Retrospective cohort study. To study clinical and radiologic outcomes after anterior cervical discectomy and fusion (ACDF) using a zero-profile anchored spacer compared with a standard interposition graft with anterior plating. Anterior plating increases fusion rates in ACDF but is associated with higher rates of postoperative dysphagia. Reduction of plate thickness or zero-profile fixation of the interposition graft have been suggested to decrease the incidence of postoperative dysphagia. Retrospective cohort study of 70 consecutive patients of whom the first 35 patients underwent ACDF with anterior plating and the remaining patients received an LDR device. Patient demographics, operative details, neurological impairment, complications, and radiographic imaging were reviewed. Dysphagia occurring in the immediate postoperative period and lasting for >3 months was recorded. Both the zero-profile anchored spacer and a standard interposition graft with anterior plating resulted in improvement of neurological outcome at a mean follow-up time of 13.9 months. Fusion rates were found to be similar between ACDF with anterior plating (96.0%) and LDR (95.2%). Evaluation of postoperative radiographs revealed significantly more swelling of the prevertebral space (20.4±0.9 mm) after implantation of an anterior locking plate compared with a zero-profile device (15.6±0.7 mm, P<0.001). This difference remained significant at 6-month follow-up (P=0.035). Seven patients (20%) with ACDF and plating complained about swallowing difficulties beyond 3 months compared with only 1 patient with the LDR device (P=0.027). The severity of dysphagia was mild in all but 2 patients. Both patients with moderate and severe swallowing difficulties had undergone ACDF with anterior plating. Zero-profile anchored spacers lead to similar clinical and radiographic outcomes compared with ACDF with plating and may carry a lower risk of postoperative dysphagia.

Comparison of observed and modeled cloud-free longwave downward radiation (2010-2016) at the high mountain BSRN Izaña station

NASA Astrophysics Data System (ADS)

Delia García, Rosa; Barreto, Africa; Cuevas, Emilio; Gröbner, Julian; García, Omaira Elena; Gómez-Peláez, Angel; Romero-Campos, Pedro Miguel; Redondas, Alberto; Cachorro, Victoria Eugenia; Ramos, Ramon

2018-06-01

A 7-year (2010-2016) comparison study between measured and simulated longwave downward radiation (LDR) under cloud-free conditions was performed at the Izaña Atmospheric Observatory (IZO, Spain). This analysis encompasses a total of 2062 cases distributed approximately evenly between day and night. Results show an excellent agreement between Baseline Surface Radiation Network (BSRN) measurements and simulations with libRadtran V2.0.1 and MODerate resolution atmospheric TRANsmission model (MODTRAN) V6 radiative transfer models (RTMs). Mean bias (simulated - measured) of < 1.1 % and root mean square of the bias (RMS) of < 1 % are within the instrumental error (2 %). These results highlight the good agreement between the two RTMs, proving to be useful tools for the quality control of LDR observations and for detecting temporal drifts in field instruments. The standard deviations of the residuals, associated with the RTM input parameters uncertainties are rather small, 0.47 and 0.49 % for libRadtran and MODTRAN, respectively, at daytime, and 0.49 to 0.51 % at night-time. For precipitable water vapor (PWV) > 10 mm, the observed night-time difference between models and measurements is +5 W m-2 indicating a scale change of the World Infrared Standard Group of Pyrgeometers (WISG), which serves as reference for atmospheric longwave radiation measurements. Preliminary results suggest a possible impact of dust aerosol on infrared radiation during daytime that might not be correctly parametrized by the models, resulting in a slight underestimation of the modeled LDR, of about -3 W m-2, for relatively high aerosol optical depth (AOD > 0.20).

Schools: Army Correspondence Course Program Catalog

DTIC Science & Technology

2001-10-26

Course Number: 061 M50) a. Objective. To provide an overview of targeting fundamentals to NCO with current or anticipated assignment to target production...D15) a. Objective/Scope. To provide students an overview of the DOD Reutilization and Marketing System. Emphasis is placed upon the organization and...providing an overview of financial systems, statutory controls, and programs. This course encompasses defense financial systems and controls to include

Constructions with Obstructions Involving Arcs.

ERIC Educational Resources Information Center

Wood, Dick A.

1993-01-01

Presents six construction problems in which key parts of the figure are made inaccessible, that is, a lake or an obstruction is inserted. Encourages creative thinking while improving problem-solving skills. Students are to show the construction, describe the solution, and verify correctness of the solution. (LDR)

Solid State pH Sensor Based on Light Emitting Diodes (LED) As Detector Platform

PubMed Central

Lau, King Tong; Shepherd, R.; Diamond, Danny; Diamond, Dermot

2006-01-01

A low-power, high sensitivity, very low-cost light emitting diode (LED)-based device developed for low-cost sensor networks was modified with bromocresol green membrane to work as a solid-state pH sensor. In this approach, a reverse-biased LED functioning as a photodiode is coupled with a second LED configured in conventional emission mode. A simple timer circuit measures how long (in microsecond) it takes for the photocurrent generated on the detector LED to discharge its capacitance from logic 1 (+5 V) to logic 0 (+1.7 V). The entire instrument provides an inherently digital output of light intensity measurements for a few cents. A light dependent resistor (LDR) modified with similar sensor membrane was also used as a comparison method. Both the LED sensor and the LDR sensor responded to various pH buffer solutions in a similar way to obtain sigmoidal curves expected of the dye. The pKa value obtained for the sensors was found to agree with the literature value.

Experimental Investigations on Formability of Aluminum Tailor Friction Stir Welded Blanks in Deep Drawing Process

NASA Astrophysics Data System (ADS)

Kesharwani, R. K.; Panda, S. K.; Pal, S. K.

2015-02-01

In the present work, tailor friction stir welded blanks (TFSWBs) were fabricated successfully using 2.0-mm-thick AA5754-H22 and AA5052-H32 sheet metals with optimized tool design and process parameters. Taguchi L9 orthogonal array has been used to design the friction stir welding experiments, and the Grey relational analysis has been applied for the multi objective optimization in order to maximize the weld strength and total elongation reducing the surface roughness and energy consumption. The formability of the TFSWBs and parent materials was evaluated and compared in terms of limiting drawing ratio (LDR) using a conventional circular die. It was found that the formability of the TFSWBs was comparable with that of both the parent materials without failure in the weldment. A modified conical tractrix die (MCTD) was proposed to enhance the LDR of the TFSWBs. It was found that the formability was improved by 27% using the MCTD.

Rendering of HDR content on LDR displays: an objective approach

NASA Astrophysics Data System (ADS)

Krasula, Lukáš; Narwaria, Manish; Fliegel, Karel; Le Callet, Patrick

2015-09-01

Dynamic range compression (or tone mapping) of HDR content is an essential step towards rendering it on traditional LDR displays in a meaningful way. This is however non-trivial and one of the reasons is that tone mapping operators (TMOs) usually need content-specific parameters to achieve the said goal. While subjective TMO parameter adjustment is the most accurate, it may not be easily deployable in many practical applications. Its subjective nature can also influence the comparison of different operators. Thus, there is a need for objective TMO parameter selection to automate the rendering process. To that end, we investigate into a new objective method for TMO parameters optimization. Our method is based on quantification of contrast reversal and naturalness. As an important advantage, it does not require any prior knowledge about the input HDR image and works independently on the used TMO. Experimental results using a variety of HDR images and several popular TMOs demonstrate the value of our method in comparison to default TMO parameter settings.

High-throughput multiplex HLA-typing by ligase detection reaction (LDR) and universal array (UA) approach.

PubMed

Consolandi, Clarissa

2009-01-01

One major goal of genetic research is to understand the role of genetic variation in living systems. In humans, by far the most common type of such variation involves differences in single DNA nucleotides, and is thus termed single nucleotide polymorphism (SNP). The need for improvement in throughput and reliability of traditional techniques makes it necessary to develop new technologies. Thus the past few years have witnessed an extraordinary surge of interest in DNA microarray technology. This new technology offers the first great hope for providing a systematic way to explore the genome. It permits a very rapid analysis of thousands genes for the purpose of gene discovery, sequencing, mapping, expression, and polymorphism detection. We generated a series of analytical tools to address the manufacturing, detection and data analysis components of a microarray experiment. In particular, we set up a universal array approach in combination with a PCR-LDR (polymerase chain reaction-ligation detection reaction) strategy for allele identification in the HLA gene.

Evaluation of a HDR image sensor with logarithmic response for mobile video-based applications

NASA Astrophysics Data System (ADS)

Tektonidis, Marco; Pietrzak, Mateusz; Monnin, David

2017-10-01

The performance of mobile video-based applications using conventional LDR (Low Dynamic Range) image sensors highly depends on the illumination conditions. As an alternative, HDR (High Dynamic Range) image sensors with logarithmic response are capable to acquire illumination-invariant HDR images in a single shot. We have implemented a complete image processing framework for a HDR sensor, including preprocessing methods (nonuniformity correction (NUC), cross-talk correction (CTC), and demosaicing) as well as tone mapping (TM). We have evaluated the HDR sensor for video-based applications w.r.t. the display of images and w.r.t. image analysis techniques. Regarding the display we have investigated the image intensity statistics over time, and regarding image analysis we assessed the number of feature correspondences between consecutive frames of temporal image sequences. For the evaluation we used HDR image data recorded from a vehicle on outdoor or combined outdoor/indoor itineraries, and we performed a comparison with corresponding conventional LDR image data.

Combining the pressure effect with local heat treatment for improving the sheet metal forming process

NASA Astrophysics Data System (ADS)

Palumbo, G.; Piccininni, A.; Guglielmi, P.; Sorgente, D.; Tricarico, L.

2016-08-01

The present work deals with the advantages in the Hydromechanical Deep Drawing (HDD) when AA5754 Tailored Heat Treated Blanks (THTBs) are adopted. It is well known that the creation of a suitable distribution of material properties increases the process performance. When non heat-treatable alloys are considered, the THTB approach can be successfully applied to increase the Limit Drawing Ratio (LDR) by changing the peripheral zone into the annealed state starting from a cold-worked blank. If this approach is combined with the advantages of a counterpressure, even more remarkable improvements can be achieved. Due to the large number of involved parameters, the optimized design of both the local treatment and the pressure profile were investigated coupling an axial symmetric Finite Element model with the integration platform modeFRONTIER. Results confirmed the possibility of increasing the LDR from 2.0 (Deep Drawing using a blank in the annealed state) up to about 3.0 if combining the adoption of a THTB with the optimal pressure profile.

[Developments in brachytherapy].

PubMed

Ikeda, H

1995-09-01

Brachytherapy is one of the ideal methods of radiotherapy because of the concentration of a high dose on the target. Recent developments, including induction of afterloading method, utilization of small-sized high-activity sources such as Iridium-192, and induction of high technology and computerization, have made for shortening of irradiation time and source handling, which has led to easier management of the patient during treatment. Dose distribution at high dose rate (HDR) is at least as good as that of low dose rate (LDR), and selection of fractionation and treatment time assures even greater biological effects on hypoxic tumor cells than LDR. Experience with HDR brachytherapy in uterine cervix cancer using Cobalt-60 during the past 20 years in this country has gradually been evaluated in U.S. and Europe. The indications for HDR treatment have extended to esophagus, bronchus, bile duct, brain, intraoperative placement of source guide, and perineal region using templates, as well as the conventional use for uterus, tongue and so on.

T-matrix modeling of linear depolarization by morphologically complex soot and soot-containing aerosols

NASA Astrophysics Data System (ADS)

Mishchenko, Michael I.; Liu, Li; Mackowski, Daniel W.

2013-07-01

We use state-of-the-art public-domain Fortran codes based on the T-matrix method to calculate orientation and ensemble averaged scattering matrix elements for a variety of morphologically complex black carbon (BC) and BC-containing aerosol particles, with a special emphasis on the linear depolarization ratio (LDR). We explain theoretically the quasi-Rayleigh LDR peak at side-scattering angles typical of low-density soot fractals and conclude that the measurement of this feature enables one to evaluate the compactness state of BC clusters and trace the evolution of low-density fluffy fractals into densely packed aggregates. We show that small backscattering LDRs measured with ground-based, airborne, and spaceborne lidars for fresh smoke generally agree with the values predicted theoretically for fluffy BC fractals and densely packed near-spheroidal BC aggregates. To reproduce higher lidar LDRs observed for aged smoke, one needs alternative particle models such as shape mixtures of BC spheroids or cylinders.

Cumulative Axial and Torsional Fatigue: An Investigation of Load-Type Sequencing Effects

NASA Technical Reports Server (NTRS)

Kalluri, Sreeramesh; Bonacuse, Peter J.

2000-01-01

Cumulative fatigue behavior of a wrought cobalt-base superalloy, Haynes 188 was investigated at 538 C under various single-step sequences of axial and torsional loading conditions. Initially, fully-reversed, axial and torsional fatigue tests were conducted under strain control at 538 C on thin-walled tubular specimens to establish baseline fatigue life relationships. Subsequently, four sequences (axial/axial, torsional/torsional, axial/torsional, and torsional/axial) of two load-level fatigue tests were conducted to characterize both the load-order (high/low) and load-type sequencing effects. For the two load-level tests, summations of life fractions and the remaining fatigue lives at the second load-level were computed by the Miner's Linear Damage Rule (LDR) and a nonlinear Damage Curve Approach (DCA). In general, for all four cases predictions by LDR were unconservative. Predictions by the DCA were within a factor of two of the experimentally observed fatigue lives for a majority of the cumulative axial and torsional fatigue tests.

T-Matrix Modeling of Linear Depolarization by Morphologically Complex Soot and Soot-Containing Aerosols

NASA Technical Reports Server (NTRS)

Mishchenko, Michael I.; Liu, Li; Mackowski, Daniel W.

2013-01-01

We use state-of-the-art public-domain Fortran codes based on the T-matrix method to calculate orientation and ensemble averaged scattering matrix elements for a variety of morphologically complex black carbon (BC) and BC-containing aerosol particles, with a special emphasis on the linear depolarization ratio (LDR). We explain theoretically the quasi-Rayleigh LDR peak at side-scattering angles typical of low-density soot fractals and conclude that the measurement of this feature enables one to evaluate the compactness state of BC clusters and trace the evolution of low-density fluffy fractals into densely packed aggregates. We show that small backscattering LDRs measured with groundbased, airborne, and spaceborne lidars for fresh smoke generally agree with the values predicted theoretically for fluffy BC fractals and densely packed near-spheroidal BC aggregates. To reproduce higher lidar LDRs observed for aged smoke, one needs alternative particle models such as shape mixtures of BC spheroids or cylinders.

The NASA Electronic Parts and Packaging (NEPP) Program: Overview and Update FY15 and Beyond

NASA Technical Reports Server (NTRS)

LaBel, Kenneth A.; Sampson, Michael J.

2016-01-01

The NASA Electronic Parts and Packaging (NEPP) program, and its subset the NASA Electronic Parts Assurance Group (NEPAG), are NASA's point-of-contacts for reliability and radiation tolerance of electrical, electronic, and electromechanical (EEE) parts and their packages. This presentation includes a Fiscal Year 2015 program overview.

Overview of the forest health monitoring program

Treesearch

2000-01-01

This paper presents an overview of the Forest Health Monitoring Program (FHM), a partnership among the USDA Forest Service, State Foresters, universities, and the USDI Bureau of Land Management. The purpose of FHM is to annually assess the condition of the nation's forested ecosystems in a standardized way. There are four components of the program - Detection...

Overview of the Forest Health Monitoring Program

Treesearch

2000-01-01

This paper presents an overview of the Forest Health Monitoring Program (FHM), a partnership among the USDA Forest Service, State Foresters, universities, and the USDI Bureau of Land Management. The purpose of FHM is to annually assess the condition of the Nation's forested ecosystems in a standardized way. There are four components of the program-Detection...

Individuals with Disabilities Education Act: Reauthorization Overview. CRS Report for Congress.

ERIC Educational Resources Information Center

Aleman, Steven R.

This report provides a review of programs authorized under the Individuals with Disabilities Education Act (IDEA) and an overview of potential reauthorization issues, as the second session of the 103rd Congress considers revisions to these programs. The Infants and Toddlers Program (Part H of IDEA) provides formula grants to participating States…

Human Research Program Science Management: Overview of Research and Development Activities

NASA Technical Reports Server (NTRS)

Charles, John B.

2007-01-01

An overview of research and development activities of NASA's Human Research Science Management Program is presented. The topics include: 1) Human Research Program Goals; 2) Elements and Projects within HRP; 3) Development and Maintenance of Priorities; 4) Acquisition and Evaluation of Research and Technology Proposals; and 5) Annual Reviews

75 FR 39923 - Office of Postsecondary Education; Overview Information; Pilot Program for Course Material Rental...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-13

... DEPARTMENT OF EDUCATION Office of Postsecondary Education; Overview Information; Pilot Program for... education (IHEs) for pilot programs that expand the services of bookstores to provide the option for... CFR 75.105(b)(2)(iv), this priority is from section 803 of the Higher Education Opportunity Act (HEOA...

An overview of the F-117A avionics flight test program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Silz, R.

1992-02-01

This paper is an overview of the history of the F-117A avionics flight test program. System design concepts and equipment selections are explored followed by a review of full scale development and full capability development testing. Flight testing the Weapon System Computational Subsystem upgrade and the Offensive Combat Improvement Program are reviewed. Current flight test programs and future system updates are highlighted.

SBIR/STTR Programs

NASA Technical Reports Server (NTRS)

Stegeman, James D.; Comstock, Douglas

2008-01-01

This presentation provides an overview of the NASA mission and overviews of both the Innovative Partnerships Program (IPP) and Small Business Innovation Research (SBIR) programs and how they relate to each other and to the NASA mission. Examples are provided concerning NASA technology needs and how the SBIR program has not only enabled technology development to meet those needs, but has also facilitated the infusion of that technology into the NASA mission.

An overview of PM-10 base year emissions inventories

DOT National Transportation Integrated Search

1999-01-01

This report provides an overview of the Long Term Pavement Performance (LTPP) program's analysis program. Specifically, it outlines the analysis projects that will be undertaken by the Federal Highway Administration in fiscal years 1999 and 2000 and ...

Overview of the Project Prometheus Program

NASA Technical Reports Server (NTRS)

Burdick, G. M.

2003-01-01

This presentation will give an overview of the Project Prometheus Program (PPP, formerly the Nuclear Systems Initiative, NSI) and the Jupiter Icy Moons Orbiter (JIMO) Project (a component of PPP), a mission to the three icy Galilean moons of Jupiter.

40 CFR 268.49 - Alternative LDR treatment standards for contaminated soil.

Code of Federal Regulations, 2014 CFR

2014-07-01

... for contaminated soil. 268.49 Section 268.49 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... treatment standards for contaminated soil. (a) Applicability. You must comply with LDRs prior to placing soil that exhibits a characteristic of hazardous waste, or exhibited a characteristic of hazardous...

40 CFR 268.49 - Alternative LDR treatment standards for contaminated soil.

Code of Federal Regulations, 2011 CFR

2011-07-01

... for contaminated soil. 268.49 Section 268.49 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... treatment standards for contaminated soil. (a) Applicability. You must comply with LDRs prior to placing soil that exhibits a characteristic of hazardous waste, or exhibited a characteristic of hazardous...

40 CFR 268.49 - Alternative LDR treatment standards for contaminated soil.

Code of Federal Regulations, 2012 CFR

2012-07-01

... for contaminated soil. 268.49 Section 268.49 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... treatment standards for contaminated soil. (a) Applicability. You must comply with LDRs prior to placing soil that exhibits a characteristic of hazardous waste, or exhibited a characteristic of hazardous...

40 CFR 268.49 - Alternative LDR treatment standards for contaminated soil.

Code of Federal Regulations, 2013 CFR

2013-07-01

... for contaminated soil. 268.49 Section 268.49 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... treatment standards for contaminated soil. (a) Applicability. You must comply with LDRs prior to placing soil that exhibits a characteristic of hazardous waste, or exhibited a characteristic of hazardous...

40 CFR 268.49 - Alternative LDR treatment standards for contaminated soil.

Code of Federal Regulations, 2010 CFR

2010-07-01

... for contaminated soil. 268.49 Section 268.49 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... treatment standards for contaminated soil. (a) Applicability. You must comply with LDRs prior to placing soil that exhibits a characteristic of hazardous waste, or exhibited a characteristic of hazardous...

Prostate-Specific Antigen at 4 to 5 Years After Low-Dose-Rate Prostate Brachytherapy Is a Strong Predictor of Disease-Free Survival

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lo, Andrea C.; Department of Surgery, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia; Morris, W. James, E-mail: JMorris@bccancer.bc.ca

2014-01-01

Purpose: To determine (1) the prognostic utility of prostate-specific antigen (PSA) concentration at 45 to 60 months (48mPSA) after low-dose-rate prostate brachytherapy (LDR-PB); (2) the predictors of 48mPSA; and (3) the prognostic utility of directional trends between PSA levels at 24, 36, and 48 months after LDR-PB. Methods and Materials: Between 1998 and 2008, 2223 patients with low- and intermediate-risk prostate cancer received LDR-PB monotherapy. A cohort of 1434 of these patients was identified with a documented 48mPSA and no evidence of disease relapse prior to the 48mPSA. In addition, a subset of this cohort (n=585) was identified with ≥72more » months of follow-up and documented PSA values at both 24 and 36 months after implantation. Results: Median follow-up time was 76 months. Eight-year Kaplan-Meier disease-free survival (DFS) rates were 100% vs 73.4% for patients with 48mPSA ≤0.2 vs those with >0.2 ng/mL; 99.1% versus 53.8% for a 48mPSA threshold of ≤0.4 versus >0.4 ng/mL, respectively; and 97.3% versus 0% for a threshold of ≤1.0 versus >1.0 ng/mL, respectively. On multivariate analysis, the only factor predictive of DFS was 48mPSA (P<.0001). On subset analysis (n=585), 29 patients had a PSA rise (defined as >0.2 ng/mL) between 24 and 36 months, 24 patients had a rise between 36 and 48 months, and 11 patients had rises over both intervals. Failure rates in these patients were 52%, 79%, and 100%, respectively. On multivariate analysis, initial PSA, androgen deprivation therapy, and dose to 90% of the prostate significantly correlated with 48mPSA but together accounted for only ∼5% of its total variance. Conclusions: The 48mPSA after LDR-PB is highly predictive of long-term DFS. Patients with 48mPSA ≤0.4 ng/mL had a <1% risk of disease relapse at 8 years, whereas all patients with 48mPSA >1.0 ng/mL relapsed. Consecutive PSA rises of >0.2 ng/mL from 24 to 36 months and from 36 to 48 months were also highly predictive of subsequent failure.« less

Suitability of point kernel dose calculation techniques in brachytherapy treatment planning

PubMed Central

Lakshminarayanan, Thilagam; Subbaiah, K. V.; Thayalan, K.; Kannan, S. E.

2010-01-01

Brachytherapy treatment planning system (TPS) is necessary to estimate the dose to target volume and organ at risk (OAR). TPS is always recommended to account for the effect of tissue, applicator and shielding material heterogeneities exist in applicators. However, most brachytherapy TPS software packages estimate the absorbed dose at a point, taking care of only the contributions of individual sources and the source distribution, neglecting the dose perturbations arising from the applicator design and construction. There are some degrees of uncertainties in dose rate estimations under realistic clinical conditions. In this regard, an attempt is made to explore the suitability of point kernels for brachytherapy dose rate calculations and develop new interactive brachytherapy package, named as BrachyTPS, to suit the clinical conditions. BrachyTPS is an interactive point kernel code package developed to perform independent dose rate calculations by taking into account the effect of these heterogeneities, using two regions build up factors, proposed by Kalos. The primary aim of this study is to validate the developed point kernel code package integrated with treatment planning computational systems against the Monte Carlo (MC) results. In the present work, three brachytherapy applicators commonly used in the treatment of uterine cervical carcinoma, namely (i) Board of Radiation Isotope and Technology (BRIT) low dose rate (LDR) applicator and (ii) Fletcher Green type LDR applicator (iii) Fletcher Williamson high dose rate (HDR) applicator, are studied to test the accuracy of the software. Dose rates computed using the developed code are compared with the relevant results of the MC simulations. Further, attempts are also made to study the dose rate distribution around the commercially available shielded vaginal applicator set (Nucletron). The percentage deviations of BrachyTPS computed dose rate values from the MC results are observed to be within plus/minus 5.5% for BRIT LDR applicator, found to vary from 2.6 to 5.1% for Fletcher green type LDR applicator and are up to −4.7% for Fletcher-Williamson HDR applicator. The isodose distribution plots also show good agreements with the results of previous literatures. The isodose distributions around the shielded vaginal cylinder computed using BrachyTPS code show better agreement (less than two per cent deviation) with MC results in the unshielded region compared to shielded region, where the deviations are observed up to five per cent. The present study implies that the accurate and fast validation of complicated treatment planning calculations is possible with the point kernel code package. PMID:20589118

Guide to U.S. Department of Education Programs. Fiscal Year 2011

ERIC Educational Resources Information Center

US Department of Education, 2011

2011-01-01

This paper provides an overview of U.S. Department of Education programs authorized and funded under federal law. It includes information as well on the laboratories, centers, and other facilities funded by the Department that provide important resources for education. Each entry, which gives a brief overview of a program or resource, is listed…

Overview of Integrated Child Development Services Programme in India: Some Policy Implications for Nepal.

ERIC Educational Resources Information Center

Shrestha, Kishor

This paper presents an overview of the Integrated Child Development Services (ICDS) program in India, discusses the context of Early Childhood Education (ECE) in Nepal, analyzes the best practices of the ICDS, and draws some policy implications for improving ECE in Nepal. The ICDS program is an integrated child development program with the…

PMC's Florida Bay & Adjacent Marine Systems Science Program

Science.gov Websites

Florida Bay and Adjacent Marine Systems Science Program Inverted image, click link below to view actual image and caption click to display actual image and caption Program Overview Management & - January 2002 >For more, click here to view the What's New Page... | Main | Overview | Management &

13 CFR 142.1 - Overview of regulations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Overview of regulations. 142.1 Section 142.1 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION PROGRAM FRAUD CIVIL REMEDIES ACT REGULATIONS Overview and Definitions § 142.1 Overview of regulations. (a) Statutory basis. This...

Science to Protect Public Health and the Environment--EPA Research Program Overview 2016-2019

EPA Pesticide Factsheets

This document provides an overview of EPA’s research programs within the Office of Research and Development. This critically important work is providing the science needed to address the biggest problems facing environmental science.

24 CFR 92.1 - Overview.

Code of Federal Regulations, 2010 CFR

2010-04-01

... INVESTMENT PARTNERSHIPS PROGRAM General § 92.1 Overview. This part implements the HOME Investment Partnerships Act (the HOME Investment Partnerships Program). In general, under the HOME Investment Partnerships... jurisdictions may use HOME funds to carry out multi-year housing strategies through acquisition, rehabilitation...

The Environment for Application Software Integration and Execution (EASIE) version 1.0. Volume 1: Executive overview

NASA Technical Reports Server (NTRS)

Rowell, Lawrence F.; Davis, John S.

1989-01-01

The Environment for Application Software Integration and Execution (EASIE) provides a methodology and a set of software utility programs to ease the task of coordinating engineering design and analysis codes. EASIE was designed to meet the needs of conceptual design engineers that face the task of integrating many stand-alone engineering analysis programs. Using EASIE, programs are integrated through a relational database management system. Volume 1, Executive Overview, gives an overview of the functions provided by EASIE and describes their use. Three operational design systems based upon the EASIE software are briefly described.

The Relationship among Mathematics Achievement, Affective Variables and Home Background.

ERIC Educational Resources Information Center

Wong, Ngai-ying

1992-01-01

Investigated the relationships among mathematics achievement, affect, and home background for Hong Kong students (n=1766) in grades 7-13. Achievement was most closely related to academic and nonacademic self-concepts and attitudes toward mathematics, and the latter was most influenced by self- and parental expectations. (LDR)

Policy Statement: Clarification of the Dilution Prohibition and Combustion of Inorganic Metal-Bearing Hazardous Wastes for Land Disposal Restrictions

EPA Pesticide Factsheets

This memorandum sets out a Statement of Policy under the RCRA clarifying the application of the Land Disposal Restrictions (LDR) prohibition on dilution (see 40 CFR 268.3) to combustion of certain inorganic metal-bearing hazardous wastes.

76 FR 2349 - Office of Postsecondary Education; Overview Information; Business and International Education...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-13

... DEPARTMENT OF EDUCATION Office of Postsecondary Education; Overview Information; Business and International Education Program Notice inviting applications for new awards for fiscal year (FY) 2011. Catalog... Business and International Education (BIE) Program provides grants to enhance international business...

Aviation Safety Program: Weather Accident Prevention (WxAP) Project Overview and Status

NASA Technical Reports Server (NTRS)

Nadell, Shari-Beth

2003-01-01

This paper presents a project overview and status for the Weather Accident Prevention (WxAP) aviation safety program. The topics include: 1) Weather Accident Prevention Project Background/History; 2) Project Modifications; 3) Project Accomplishments; and 4) Project's Next Steps.

OVERVIEW OF USEPA'S SMALL SYSTEMS DEMONSTRATION PROGRAM

EPA Science Inventory

This presentation provides an overview of the USEPA Arsenic Treatment Technology Demonstration Program. The information includes the status of the projects on both round 1 and round 2 including some photos of the treatment systems. Limited information is given on the results of t...

OVERVIEW OF VOLUNTARY STEWARDSHIP EFFORTS TO ADDRESS PHARMACEUTICAL DISPOSAL

EPA Science Inventory

This presentation will provide an overview of current federal regulatory guidance for pharmaceutical disposal, currently funded pilot programs for take-back pilot studies, and state programs. The EPA Office of Water's role is to protect our Nation's watersheds and drinking water ...

Reducing Youth Gun Violence. Part One--An Overview [and] Part Two--Prevention and Intervention Programs.

ERIC Educational Resources Information Center

McEvoy, Alan, Ed.

1996-01-01

This document contains two issues of a journal on reducing youth gun violence, reprinted from a report by the U.S. Department of Justice. The first issue, part one, provides an overview of programs and initiatives. The second issue, part two, describes prevention and intervention programs. To reduce violence and build healthy communities requires…

Technology advancements for the U.S. manned Space Station - An overview

NASA Technical Reports Server (NTRS)

Simon, William E.

1987-01-01

The structure and methodology of the Johnson Space Center (JSC) advanced development program is described. An overview of the program is given, and the technology transfer process to other disciplines is described. The test bed and flight experiment programs are described, as is the technology assessment which was performed at the end of the Phase B program. The technology program within each discipline is summarized, and the coordination and integration of the JSC program with the activities of other NASA centers and with work package contractors are discussed.

OVERVIEW OF WET-WEATHER RESEARCH PROGRAM

EPA Science Inventory

This paper presents an overview of EPA,s wet-weather flow (WWF) research program, which was expanded in October 1995 with the establishment of the Urban Watershed Management Branch at Edison, New Jersey. Research priorities for 1998-1999 are presented as well as efforts to col...

24 CFR 3286.5 - Overview of installation program.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Overview of installation program. 3286.5 Section 3286.5 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR HOUSING-FEDERAL HOUSING COMMISSIONER, DEPARTMENT OF...

Overview: MINNEMAST.

ERIC Educational Resources Information Center

Adams, Patricia A., Ed.

This illustrated booklet provides a rationale and overview for the twenty-nine coordinated mathematics and science units in the MINNEMAST program for kindergarten through third grade. The rationale for the program cites both the historical association of mathematics and science and pedagogical advantages. The goals of the project are to provide…

Overview of DOE space nuclear propulsion programs

NASA Technical Reports Server (NTRS)

Newhouse, Alan R.

1993-01-01

An overview of Department of Energy space nuclear propulsion programs is presented in outline and graphic form. DOE's role in the development and safety assurance of space nuclear propulsion is addressed. Testing issues and facilities are discussed along with development needs and recent research activities.

JSC ECLSS R/T Program Overview

NASA Technical Reports Server (NTRS)

Behrend, A. F.

1990-01-01

Viewgraphs on Johnson Space Center Environmental Control and Life Support System (ECLSS) research and technology program overview are presented. Topics covered include: advancements in electrochemical CO2 removal; supercritical water waste oxidation; electrooxidation for post-treatment of reclaimed water; and photocatalytic post-treatment of reclaimed water.

An Overview of Audacity

ERIC Educational Resources Information Center

Thompson, Douglas Earl

2014-01-01

This article is an overview of the open source audio-editing and -recording program, Audacity. Key features are noted, along with significant features not included in the program. A number of music and music technology concepts are identified that could be taught and/or reinforced through using Audacity.

THE U.S. EVIRONMENTAL PROTECTION AGENCY ENVIRONMENTAL TECHNOLOGY VERIFICATION PROGRAM—AN OVERVIEW

EPA Science Inventory

This is an article about monitoring technologies in the Environmental Technolgy Verification (ETV) Program which will be published in the Journal of Occupational And Environmental Hygiene. This article gives an overview of the entire ETV program with emphasis on monitoring techn...

2002 NASA Seal/Secondary Air System Workshop. Volume 1

NASA Technical Reports Server (NTRS)

Steinetz, Bruce M. (Editor); Hendricks, Robert C. (Editor)

2003-01-01

The 2002 NASA Seal/Secondary Air System Workshop covered the following topics: (i) Overview of NASA s perspective of aeronautics and space technology for the 21st century; (ii) Overview of the NASA-sponsored Ultra-Efficient Engine Technology (UEET), Turbine-Based Combined-Cycle (TBCC), and Revolutionary Turbine Accelator (RTA) programs; (iii) Overview of NASA Glenn's seal program aimed at developing advanced seals for NASA's turbomachinery, space propulsion, and reentry vehicle needs; (iv) Reviews of sealing concepts, test results, experimental facilities, and numerical predictions; and (v) Reviews of material development programs relevant to advanced seals development. The NASA UEET and TBCC/RTA program overviews illustrated for the reader the importance of advanced technologies, including seals, in meeting future turbine engine system efficiency and emission goals. For example, the NASA UEET program goals include an 8- to 15-percent reduction in fuel burn, a 15-percent reduction in CO2, a 70-percent reduction in NOx, CO, and unburned hydrocarbons, and a 30-dB noise reduction relative to program baselines. The workshop also covered several programs NASA is funding to investigate advanced reusable space vehicle technologies (X-38) and advanced space ram/scramjet propulsion systems. Seal challenges posed by these advanced systems include high-temperature operation, resiliency at the operating temperature to accommodate sidewall flexing, and durability to last many missions.

SEWER SEDIMENT CONTROL: AN OVERVIEW OF THE EPA WET WEATHER FLOW (WWF) RESEARCH PROGRAM

EPA Science Inventory

This paper presents an overview of EPA WWF Research Program projects related to causes of sewer solids deposition and control methods that can prevent accumulation of sewer sediments. In particular, discussion will focus on the relationship of wastewater characteristics to flow ...

SEWER-SEDIMENT CONTROL: OVERVIEW OF AN EPA WET-WEATHER FLOW RESEARCH PROGRAM

EPA Science Inventory

This paper presents a historical overview of the sewer sediment control projects conducted by the Wet-Weather Flow Research Program of the USEPA. Research presented includes studies of the causes of sewer solids deposition and development/evaluation of control methods that can pr...

Soil and hydrology sciences need laboratory and field experiments in the classroom. An example from the SEDER (Soil Erosion and Degradation Research Group) from the University of Valencia

NASA Astrophysics Data System (ADS)

Cerdà, Artemi; González Pelayo, Óscar; García Orenes, Fuensanta; Jordán, Antonio; Pereira, Paulo; Novara, Agata; Úbeda, Xavier

2015-04-01

The use of experimental stations and long-term measurements in the field and in the laboratory contributed to large datasets and key information to understand the soil system and the hydrological cycle (Neal et al., 2011; García Orenes et al., 2012; López-Garrido et al., 2012; Kröpf et al., 2013; Nadal-Romero, 2013; Taguas et al., 2013; Zhao et al., 2013). However, teaching in high schools and colleagues require simple experiments to help the students to understand the soil and water resources and management. We show here the experiments and measurements we conduct within the teaching program of the Soil Erosion and Degradation Research Group at the University of Valencia to help the students in the understanding of the soil and hydrologic processes. The expereriments and measurements developed are the following: (i) Water Drop Penetration Time (WDPT) to determine the soil water repellency; (ii) Leaves water retention capacity measured in the field; (iii) soil infiltration capacity measured with simple ring infiltrometers; (iv) measurement of the soil bulk density; and (v) measurement of the soil water content. Those experiments and measurements are applied to agriculture, rangeland and fire affected soils. Acknowledgements To the "Ministerio de Economía and Competitividad" of Spanish Government for finance the POSTFIRE project (CGL2013- 47862-C2-1-R). The research projects GL2008-02879/BTE, LEDDRA 243857 and PREVENTING AND REMEDIATING DEGRADATION OF SOILS IN EUROPE THROUGH LAND CARE (RECARE)FP7-ENV-2013- supported this research. References García-Orenes, F., Roldán, A., Mataix-Solera, J., Cerdà, A., Campoy, M., Arcenegui, V., Caravaca, F. 2012 Soil structural stability and erosion rates influenced by agricultural management practices in a semi-arid Mediterranean agro-ecosystem. Soil Use and Management 28(4): 571-579. DOI: 10.1111/j.1475-2743.2012.00451.x Kröpfl, A. I., Cecchi, G. A., Villasuso, N. M., Distel, R. A. 2013. Degradation and recovery processes in Semi-Arid patchy rangelands of northern Patagonia, Argentina. Land Degradation & Development, 24: 393- 399. DOI 10.1002/ldr.1145 López-Garrido, R., Deurer, M., Madejón, E., Murillo, J. M., Moreno, F. 2012. Tillage influence on biophysical soil properties: The example of a long-term tillage experiment under Mediterranean rainfed conditions in South Spain. Soil and Tillage Research, 118, 52-60. Mekuria, W., Aynekulu, E. 2013. Exclosure land management for restoration of the soils in degrade communal grazing lands in Northern Ethiopia. Land Degradation & Development, 24: 528- 538. DOI 10.1002/ldr.1146 Nadal-Romero, E., Lasanta, T., García-Ruiz, J. M. 2013. Runoff and sediment yield from land under various uses in a Mediterranean mountain area: long-term results from an experimental station. Earth Surface Processes and Landforms, 38(4), 346-355. Neal, C., Reynolds, B., Norris, D., Kirchner, J. W., Neal, M., Rowland, P., Wright, D. 2011. Three decades of water quality measurements from the Upper Severn experimental catchments at Plynlimon, Wales: an openly accessible data resource for research, modelling, environmental management and education. Hydrological Processes, 25(24), 3818-3830. Taguas, E. V., Carpintero, E., and Ayuso, J. L. 2013. Assessing land degradation risk through the long-term analysis of erosivity: a case study in Southern Spain. Land Degradation & Development, 24: 179- 187. DOI 10.1002/ldr.1119 Zhao, G., Mu, X., Wen, Z., Wang, F., and Gao, P. 2013. Soil erosion, conservation, and Eco-environment changes in the Loess Plateau of China. Land Degradation & Development, 24: 499- 510. DOI 10.1002/ldr.2246

The Center for the Study of Social Organization of Schools and the Learning Process. Third Annual Report.

ERIC Educational Resources Information Center

McDill, Edward L.; And Others

A basic overview of Research and Development (R and D) Centers programs, and the various larger institutions of which they are a part, is given. The administrative and program structure of the Johns Hopkins R and D Center follows, with an organizational chart, staff list, and a program and project register included. A descriptive overview of the…

Overview of NASA GRC's Efforts In SWBLI

NASA Technical Reports Server (NTRS)

Long-Davis, Mary Jo

2017-01-01

Overview of NASA Efforts (related to SWBLI research) An overview of NASA's restructured ARMD Program and the resulting new projects. Areas of research pertaining to shock wave boundary layer interaction are highlighted. Plans and status for specific tasks are presented.

Student Retention and Persistence to Graduation: Effects of an Introductory Life Calling Course

ERIC Educational Resources Information Center

Conner, Shanna L.; Daugherty, Douglas A.; Gilmore, Megan N.

2013-01-01

The researchers examined the effect of a course, Introduction to Life Calling (LDR150), on retention and persistence to graduation at a private, Midwestern university. The course emphasizes self-assessment, student-faculty engagement, personal values, and the student's developing sense of Life Calling. The subjects consisted of 3338 students who…

Emotional Competence and Drop-Out Rates in Higher Education

ERIC Educational Resources Information Center

Kingston, Emma

2008-01-01

Purpose: The purpose of this paper is to compare the emotional competence of first year undergraduates enrolled on a high or low drop-out rate (HDR and LDR, respectively) course, at a newly established university within the UK. Design/methodology/approach: A mixed methods approach using both quantitative and qualitative data collection methods was…

RCRA, superfund and EPCRA hotline training module. Introduction to: Containment buildings (40 cfr parts 264/265, subpart dd) updated July 1996

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1996-07-01

The module outlines the regulatory history and purpose of containment buildings. It disucsses the relationship between LDR and containment buildings. It summarizes the design and operating standard applicable to containment buildings and describes the relationship between generator accumulation standards and containment buildings.

Evaluation of privacy in high dynamic range video sequences

NASA Astrophysics Data System (ADS)

Řeřábek, Martin; Yuan, Lin; Krasula, Lukáš; Korshunov, Pavel; Fliegel, Karel; Ebrahimi, Touradj

2014-09-01

The ability of high dynamic range (HDR) to capture details in environments with high contrast has a significant impact on privacy in video surveillance. However, the extent to which HDR imaging affects privacy, when compared to a typical low dynamic range (LDR) imaging, is neither well studied nor well understood. To achieve such an objective, a suitable dataset of images and video sequences is needed. Therefore, we have created a publicly available dataset of HDR video for privacy evaluation PEViD-HDR, which is an HDR extension of an existing Privacy Evaluation Video Dataset (PEViD). PEViD-HDR video dataset can help in the evaluations of privacy protection tools, as well as for showing the importance of HDR imaging in video surveillance applications and its influence on the privacy-intelligibility trade-off. We conducted a preliminary subjective experiment demonstrating the usability of the created dataset for evaluation of privacy issues in video. The results confirm that a tone-mapped HDR video contains more privacy sensitive information and details compared to a typical LDR video.

Fatigue Life Estimation under Cumulative Cyclic Loading Conditions

NASA Technical Reports Server (NTRS)

Kalluri, Sreeramesh; McGaw, Michael A; Halford, Gary R.

1999-01-01

The cumulative fatigue behavior of a cobalt-base superalloy, Haynes 188 was investigated at 760 C in air. Initially strain-controlled tests were conducted on solid cylindrical gauge section specimens of Haynes 188 under fully-reversed, tensile and compressive mean strain-controlled fatigue tests. Fatigue data from these tests were used to establish the baseline fatigue behavior of the alloy with 1) a total strain range type fatigue life relation and 2) the Smith-Wastson-Topper (SWT) parameter. Subsequently, two load-level multi-block fatigue tests were conducted on similar specimens of Haynes 188 at the same temperature. Fatigue lives of the multi-block tests were estimated with 1) the Linear Damage Rule (LDR) and 2) the nonlinear Damage Curve Approach (DCA) both with and without the consideration of mean stresses generated during the cumulative fatigue tests. Fatigue life predictions by the nonlinear DCA were much closer to the experimentally observed lives than those obtained by the LDR. In the presence of mean stresses, the SWT parameter estimated the fatigue lives more accurately under tensile conditions than under compressive conditions.

Objective quality assessment of tone-mapped images.

PubMed

Yeganeh, Hojatollah; Wang, Zhou

2013-02-01

Tone-mapping operators (TMOs) that convert high dynamic range (HDR) to low dynamic range (LDR) images provide practically useful tools for the visualization of HDR images on standard LDR displays. Different TMOs create different tone-mapped images, and a natural question is which one has the best quality. Without an appropriate quality measure, different TMOs cannot be compared, and further improvement is directionless. Subjective rating may be a reliable evaluation method, but it is expensive and time consuming, and more importantly, is difficult to be embedded into optimization frameworks. Here we propose an objective quality assessment algorithm for tone-mapped images by combining: 1) a multiscale signal fidelity measure on the basis of a modified structural similarity index and 2) a naturalness measure on the basis of intensity statistics of natural images. Validations using independent subject-rated image databases show good correlations between subjective ranking score and the proposed tone-mapped image quality index (TMQI). Furthermore, we demonstrate the extended applications of TMQI using two examples-parameter tuning for TMOs and adaptive fusion of multiple tone-mapped images.

COLLECTION SYSTEM SOLIDS CONTROL: OVERVIEW OF AN EPA WET-WEATHER FLOW RESEARCH PROGRAM

EPA Science Inventory

This paper presents an historical overview of the sewer-solids control projects conducted by the Wet-Weather Flow Research Program of the US EPA. Research includes studies of the causes of sewer-solids deposition and development/evaluation of control methods that can prevent sewe...

Human interferon and its inducers: clinical program overview at Roswell Park Memorial Institute.

PubMed

Carter, W A; Horoszewicz, J S

1978-11-01

An overview of the clinical interferon program at Roswell Park Memorial Institute is presented. Purified fibroblast interferon and a novel inducer of human interferon [rIn-r(C12,U)n] are being evaluated for possible antiviral, antiproliferative, and immunomodulatory activities in patients with cancer.

Research Overview: Implications for Staff Development. Higher Education in TAFE. Monograph Series 01/2009

ERIC Educational Resources Information Center

Moodie, Gavin; Wheelahan, Leesa; Billett, Stephen; Kelly, Ann

2009-01-01

A project funded through the National Vocational Education and Training Research and Evaluation program investigated higher education programs--mostly bachelor's and associate degrees--offered by technical and further education (TAFE) institutes. This overview highlights some of the implications for staff development identified through this…

Research Overview: Implications for TAFE Managers. Higher education in TAFE. Monograph Series 01/2009

ERIC Educational Resources Information Center

Moodie, Gavin; Wheelahan, Leesa; Billett, Stephen; Kelly, Ann

2009-01-01

A project funded through the National Vocational Education and Training Research and Evaluation program investigated higher education programs--mostly bachelor's and associate degrees--offered by technical and further education (TAFE) institutes. This overview highlights the implications for TAFE management identified through this project. [This…

Research Overview: Implications for Teachers. Higher Education in TAFE. Monograph Series 01/2009

ERIC Educational Resources Information Center

Moodie, Gavin; Wheelahan, Leesa; Billett, Stephen; Kelly, Ann

2009-01-01

A project funded through the National Vocational Education and Training Research and Evaluation program investigated higher education programs--mostly bachelor's and associate degrees--offered by technical and further education (TAFE) institutes. This overview highlights some of the implications for teachers identified by this project. [This…

Research Overview on Status: Higher Education in TAFE. Monograph Series 01/2009

ERIC Educational Resources Information Center

Moodie, Gavin; Wheelahan, Leesa; Billett, Stephen; Kelly, Ann

2009-01-01

A project funded through the National Vocational Education and Training Research and Evaluation program investigated higher education programs--mostly bachelor's and associate degrees--offered by technical and further education (TAFE) institutes. This overview highlights some of the issues associated with the perceived status of TAFE higher…

DOE Hydrogen & Fuel Cell Overview

DTIC Science & Technology

2011-01-13

Overview of Combined Heat+Power PowerElectricity Natural Gas Heat + Cooling Natural Gas or Biogas ...Fuel Cell Technologies Program eere.energy.gov Source: US DOE 10/2010 Biogas Benefits: Preliminary Analysis Stationary fuel...with the national grid. Source: US DOE 1/2011 6 | Fuel Cell Technologies Program eere.energy.gov Biogas Resource Example

Proposed Plan for Magnet Schools--Cleveland Public Schools. Section I: Overview of Magnet Program.

ERIC Educational Resources Information Center

Fleming, Margaret, Ed.; And Others

This report presents an overview of Cleveland's proposed magnet program for facilitating school desegregation and improving educational opportunities for students from diverse ethnic/racial backgrounds. Included are discussions of individual student needs, strategies for improved instruction, possible community impact, the United States Office of…

X-43A Project Overview: Adventures in Hypersonics

NASA Technical Reports Server (NTRS)

Davis, Mark; Grindle, Laurie

2007-01-01

A viewgraph presentation describing the hypersonics program at NASA Dryden Flight Research Center is shown. The topics include: 1) X-43A Program Overview; 2) Vehicle Description; 3) Flight 1, MIB & Return to Flight; 4) Flight 2 and Results; 5) Flight 3 and Results; and 6) Concluding Remarks

Handicapped Children's Early Education Program. 1982-83 Overview and Directory.

ERIC Educational Resources Information Center

Assael, Daniel, Ed.

The document serves as a directory of federal projects in the Handicapped Children's Early Education Program (HCEEP). An introduction describes the HCEEP network and briefly summarizes results of a recent evaluation study. The overview section then describes the five types of HCEEP projects: deomonstration projects, outreach projects, state…

PAA, WSH, and CIS Overview Self-Study #47656

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schroeder, Rachel Anne

This course presents an overview of the Department of Energy’s (DOE’s) regulatory requirements relevant to the Price-Anderson Amendments Act (PAAA, also referred to as nuclear safety), worker safety and health (WSH), and classified information security (CIS) that are enforceable under the DOE enforcement program; describes the DOE enforcement process; and provides an overview of Los Alamos National Laboratory’s (LANL’s) internal compliance program relative to these DOE regulatory requirements. The LANL PAAA Program is responsible for maintaining LANL’s internal compliance program, which ensures the prompt identification, screening, and reporting of noncompliances to DOE regulatory requirements pertaining to nuclear safety, WSH, andmore » CIS to build the strongest mitigation position for the Laboratory with respect to civil or other penalties.« less

Employee assistance programs: an overview and suggested roles for psychiatrists.

PubMed

Brill, P; Herzberg, J; Speller, J L

1985-07-01

Although employee assistance programs are rapidly becoming the predominant vehicle for the delivery of mental health services in occupational settings, few programs employ a psychiatrist on either a part-time or a full-time basis. After providing an overview of the need for, cost-effectiveness of, and current status of employee assistance programs, the authors draw on their own experiences with employee assistance programs to present four broad categories of roles the psychiatrist can assume in such programs: clinician, supervisor and educator, administrator, and organizational consultant. Problems encountered in these roles are also discussed.

Have You Been Oriented? An Analysis of New Student Orientation and E-Orientation Programs at U.S. Community Colleges

ERIC Educational Resources Information Center

Chan, Matthew

2017-01-01

This study provides an overview and a snapshot of new student orientation (NSO) and new student e-orientation (NSEO) programs, with a focus on the content and feature analysis of the NSEOs. It offers an overview of currently available NSO programs of 100 randomly selected community colleges from a master list of nearly 900 community colleges in…

Time-driven activity-based cost comparison of prostate cancer brachytherapy and intensity-modulated radiation therapy.

PubMed

Dutta, Sunil W; Bauer-Nilsen, Kristine; Sanders, Jason C; Trifiletti, Daniel M; Libby, Bruce; Lash, Donna H; Lain, Melody; Christodoulou, Deborah; Hodge, Constance; Showalter, Timothy N

To evaluate the delivery cost of frequently used radiotherapy options offered to patients with intermediate- to high-risk prostate cancer using time-driven activity-based costing and compare the results with Medicare reimbursement and relative value units (RVUs). Process maps were created to represent each step of prostate radiotherapy treatment at our institution. Salary data, equipment purchase costs, and consumable costs were factored into the cost analysis. The capacity cost rate was determined for each resource and calculated for each treatment option from initial consultation to its completion. Treatment options included low-dose-rate brachytherapy (LDR-BT), combined high-dose-rate brachytherapy single fraction boost with 25-fraction intensity-modulated radiotherapy (HDR-BT-IMRT), moderately hypofractionated 28-fraction IMRT, conventionally fractionated 39-fraction IMRT, and conventionally fractionated (2 Gy/fraction) 23-fraction pelvis irradiation with 16-fraction prostate boost. The total cost to deliver LDR-BT, HDR-BT-IMRT, moderately hypofractionated 28-fraction IMRT, conventionally fractionated 39-fraction IMRT, conventionally fractionated 39-fraction IMRT, and conventionally fractionated (2 Gy/fraction) 23-fraction pelvis irradiation with 16-fraction prostate boost was $2719, $6517, $4173, $5507, and $5663, respectively. Total reimbursement for each course was $3123, $10,156, $7862, $9725, and $10,377, respectively. Radiation oncology attending time was 1.5-2 times higher for treatment courses incorporating BT. Attending radiation oncologist's time consumed per RVU was higher with BT (4.83 and 2.56 minutes per RVU generated for LDR-BT and HDR-BT-IMRT, respectively) compared to without BT (1.41-1.62 minutes per RVU). Time-driven activity-based costing analysis identified higher delivery costs associated with prostate BT compared with IMRT alone. In light of recent guidelines promoting BT for intermediate- to high-risk disease, re-evaluation of payment policies is warranted to encourage BT delivery. Copyright © 2018 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

WE-DE-201-04: Cross Validation of Knowledge-Based Treatment Planning for Prostate LDR Brachytherapy Using Principle Component Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roper, J; Ghavidel, B; Godette, K

Purpose: To validate a knowledge-based algorithm for prostate LDR brachytherapy treatment planning. Methods: A dataset of 100 cases was compiled from an active prostate seed implant service. Cases were randomized into 10 subsets. For each subset, the 90 remaining library cases were registered to a common reference frame and then characterized on a point by point basis using principle component analysis (PCA). Each test case was converted to PCA vectors using the same process and compared with each library case using a Mahalanobis distance to evaluate similarity. Rank order PCA scores were used to select the best-matched library case. Themore » seed arrangement was extracted from the best-matched case and used as a starting point for planning the test case. Any subsequent modifications were recorded that required input from a treatment planner to achieve V100>95%, V150<60%, V200<20%. To simulate operating-room planning constraints, seed activity was held constant, and the seed count could not increase. Results: The computational time required to register test-case contours and evaluate PCA similarity across the library was 10s. Preliminary analysis of 2 subsets shows that 9 of 20 test cases did not require any seed modifications to obtain an acceptable plan. Five test cases required fewer than 10 seed modifications or a grid shift. Another 5 test cases required approximately 20 seed modifications. An acceptable plan was not achieved for 1 outlier, which was substantially larger than its best match. Modifications took between 5s and 6min. Conclusion: A knowledge-based treatment planning algorithm for prostate LDR brachytherapy is being cross validated using 100 prior cases. Preliminary results suggest that for this size library, acceptable plans can be achieved without planner input in about half of the cases while varying amounts of planner input are needed in remaining cases. Computational time and planning time are compatible with clinical practice.« less

A single institution analysis of low-dose-rate brachytherapy: 5-year reported survival and late toxicity outcomes

PubMed Central

Spencer, Sandra; Guerrieri, Mario; Ding, Wei; Goharian, Mehran; Ho, Huong; Ng, Michael; Healey, Danielle; Tan, Alwin; Cham, Chee; Joon, Daryl Lim; Lawrentschuk, Nathan; Travis, Douglas; Sengupta, Shomik; Chan, Yee; Troy, Andrew; Pham, Trung; Clarke, David; Liodakis, Peter; Bolton, Damien

2018-01-01

Purpose To report the 5-year biochemical relapse-free survival (BRFS), overall survival (OS), and long-term toxicity outcomes of patients treated with low-dose-rate (LDR) brachytherapy as monotherapy for low- to intermediate-risk prostate cancer. Material and methods Between 2004 and 2011, 371 patients were treated with LDR brachytherapy as monotherapy. Of these, 102 patients (27%) underwent transurethral resection of the prostate (TURP) prior to implantation. Follow-up was performed every 3 months for 12 months, then every 6 months over 4 years and included prostate specific antigen evaluation. The biochemical relapse-free survival (BRFS) was defined according to the Phoenix criteria. Acute and late toxicities were documented using the Common Terminology Criteria for Adverse Events version 4.0. The BRFS and OS estimates were calculated using Kaplan-Meier plots. Univariate and multivariate analyses were performed to evaluate outcomes by pre-treatment clinical prognostic factors and radiation dosimetry. Results The median follow-up of all patients was 5.45 years. The 5-year BRFS and OS rates were 95% and 96%, respectively. The BRFS rates for patients with Gleason score (GS) > 7 and GS ≤ 6 were 96% and 91% respectively (p = 0.06). On univariate analysis, T1 and T2 staging, risk-group classification, and prostate volumes had no impact on survival at 5 years (p > 0.1). Late grade 2 and 3 genitourinary (GU) toxicities were observed in 10% and 5% of patients respectively. Additionally, patients with prior TURP had a greater incidence of late grade 2 or 3 urinary retention (p = 0.001). There were 14 deaths in total; however, none were attributed to prostate cancer. Conclusions LDR brachytherapy is an effective treatment option in low- to intermediate-risk prostate cancer patients. We observed low biochemical relapse rates and minimal GU toxicities several years after treatment in patients with or without TURP. However, a small risk of urinary retention was observed in some patients. PMID:29789764

The American brachytherapy society survey of brachytherapy practice for carcinoma of the cervix in the United States.

PubMed

Nag, S; Orton, C; Young, D; Erickson, B

1999-04-01

The purpose of this study was to survey the brachytherapy practice for cervical cancer in the United States. The Clinical Research Committee of the American Brachytherapy Society (ABS) performed a retrospective survey of individual physicians of the ABS and American Society of Therapeutic Radiologists and Oncologists regarding the details of the brachytherapy techniques they personally used in the treatment of cervical cancer patients for the year 1995. The replies (some of which may have been an estimate only) were tabulated. The scope of this survey did not allow us to verify the data by chart audits. A total of about 3500 questionnaires were mailed out; 521 responses were received. Of these responders, 206 (40%) did not perform any brachytherapy for carcinoma of the cervix in 1995. Of the other 315 responders reporting a total of 4892 patients treated in 1995, 88% used low dose rate (LDR) while 24% used high dose rate (HDR). There was a wide variation in the doses used. For LDR treatments, the median total external beam radiation therapy (EBRT) dose was 45 and 50 Gy and the LDR dose was 42 and 45 Gy for early and advanced cancers, respectively. For HDR treatments, the median EBRT dose was 48 and 50 Gy and the median HDR dose was 29 and 30 Gy for early and advanced cancers, respectively. The median dose per fraction was 6 Gy for a median of five fractions. Interstitial brachytherapy was used as a component of the treatment in 6% of the patients by 21% of responders. Very few responders treated with pulsed or medium dose rates. This retrospective survey showed the current brachytherapy practice pattern in the treatment of cervical cancer in the United States and can serve as a basis for future prospective national brachytherapy data registry. There was wide variation in the practice pattern, emphasizing the urgent need for consensus on these issues. Copyright 1999 Academic Press.

Directional interstitial brachytherapy from simulation to application

NASA Astrophysics Data System (ADS)

Lin, Liyong

Organs at risk (OAR) are sometimes adjacent to or embedded in or overlap with the clinical target volume (CTV) to be treated. The purpose of this PhD study is to develop directionally low energy gamma-emitting interstitial brachytherapy sources. These sources can be applied between OAR to selectively reduce hot spots in the OARs and normal tissues. The reduction of dose over undesired regions can expand patient eligibility or reduce toxicities for the treatment by conventional interstitial brachytherapy. This study covers the development of a directional source from design optimization to construction of the first prototype source. The Monte Carlo code MCNP was used to simulate the radiation transport for the designs of directional sources. We have made a special construction kit to assemble radioactive and gold-shield components precisely into D-shaped titanium containers of the first directional source. Directional sources have a similar dose distribution as conventional sources on the treated side but greatly reduced dose on the shielded side, with a sharp dose gradient between them. A three-dimensional dose deposition kernel for the 125I directional source has been calculated. Treatment plans can use both directional and conventional 125I sources at the same source strength for low-dose-rate (LDR) implants to optimize the dose distributions. For prostate tumors, directional 125I LDR brachytherapy can potentially reduce genitourinary and gastrointestinal toxicities and improve potency preservation for low risk patients. The combination of better dose distribution of directional implants and better therapeutic ratio between tumor response and late reactions enables a novel temporary LDR treatment, as opposed to permanent or high-dose-rate (HDR) brachytherapy for the intermediate risk T2b and high risk T2c tumors. Supplemental external-beam treatments can be shortened with a better brachytherapy boost for T3 tumors. In conclusion, we have successfully finished the design optimization and construction of the first prototype directional source. Potential clinical applications and potential benefits of directional sources have been shown for prostate and breast tumors.

Integrating plant and animal biology for the search of novel DNA damage biomarkers.

PubMed

Nikitaki, Zacharenia; Holá, Marcela; Donà, Mattia; Pavlopoulou, Athanasia; Michalopoulos, Ioannis; Angelis, Karel J; Georgakilas, Alexandros G; Macovei, Anca; Balestrazzi, Alma

Eukaryotic genome surveillance is dependent on the multiple, highly coordinated network functions of the DNA damage response (DDR). Highlighted conserved features of DDR in plants and animals represent a challenging opportunity to develop novel interdisciplinary investigations aimed at expanding the sets of DNA damage biomarkers currently available for radiation exposure monitoring (REM) in environmental and biomedical applications. In this review, common and divergent features of the most relevant DDR players in animals and plants are described, including the intriguing example of the plant and animal kingdom-specific master regulators SOG1 (suppressor of gamma response) and p53. The potential of chromatin remodelers as novel predictive biomarkers of DNA damage is considered since these highly evolutionarily conserved proteins provide a docking platform for the DNA repair machinery. The constraints of conventional REM biomarkers can be overcome using biomarkers identified with the help of the pool provided by high-throughput techniques. The complexity of radiation-responsive animal and plant transcriptomes and their usefulness as sources of novel REM biomarkers are discussed, focusing on ionizing (IR) and UV-radiation. The possible advantages resulting from the exploitation of plants as sources of novel DNA damage biomarkers for monitoring the response to radiation-mediated genotoxic stress are listed. Plants could represent an ideal system for the functional characterization of knockout mutations in DDR genes which compromise cell survival in animals. However, the pronounced differences between plant and animal cells need to be carefully considered in order to avoid any misleading interpretations. Radioresistant plant-based systems might be useful to explore the molecular bases of LD (low dose)/LDR (low dose rate) responses since nowadays it is extremely difficult to perform an accurate assessment of LD/LDR risk to human health. To overcome these constraints, researchers have started exploring radiotolerant non-human species as potential sources of information on the mechanisms involved in LD/LDR and general radiation responses. Copyright © 2018 Elsevier B.V. All rights reserved.

Analysis of polarization radar returns from ice clouds

NASA Astrophysics Data System (ADS)

Battaglia, A.; Sturniolo, O.; Prodi, F.

Using a modified T-matrix code, some polarimetric single-scattering radar parameters ( Zh,v, LDR h,v, ρhv, ZDR and δhv) from populations of ice crystals in ice phase at 94 GHz, modeled with axisymmetric prolate and oblate spheroidal shapes for a Γ-size distribution with different α parameter ( α=0, 1, 2) and characteristic dimension Lm varying from 0.1 to 1.8 mm, have been computed. Some of the results for different radar elevation angles and different orientation distribution for fixed water content are shown. Deeper analysis has been carried out for pure extensive radar polarimetric variables; all of them are strongly dependent on the shapes (characterised by the aspect ratio), the canting angle and the radar elevation angle. Quantities like ZDR or δhv at side incidence or LDR h and ρhv at vertical incidence can be used to investigate the preferred orientation of the particles and, in some cases, their habits. We analyze scatterplots using couples of pure extensive variables. The scatterplots with the most evident clustering properties for the different habits seem to be those in the ( ZDR [ χ=0°], δhv [ χ=0°]), in the ( ZDR [ χ=0°], LDR h [ χ=90°]) and in the ( ZDR [ χ=0°], ρhv [ χ=90°]) plane. Among these, the most appealing one seems to be that involving ZDR and ρhv variables. To avoid the problem of having simultaneous measurements with a side and a vertical-looking radar, we believe that measurements of these two extensive variables using a radar with an elevation angle around 45° can be an effective instrument to identify different habits. In particular, this general idea can be useful for future space-borne polarimetric radars involved in the studies of high ice clouds. It is also believed that these results can be used in next challenge of developing probabilistic and expert methods for identifying hydrometeor types by W-band radars.

Insights into the Performance of SD Bioline Malaria Ag P.f/Pan Rapid Diagnostic Test and Plasmodium falciparum Histidine-Rich Protein 2 Gene Variation in Madagascar.

PubMed

Willie, Nigani; Mehlotra, Rajeev K; Howes, Rosalind E; Rakotomanga, Tovonahary A; Ramboarina, Stephanie; Ratsimbasoa, Arsène C; Zimmerman, Peter A

2018-06-01

Plasmodium falciparum histidine-rich protein 2 (PfHRP2) forms the basis of many current malaria rapid diagnostic tests (RDTs). However, the parasites lacking part or all of the pfhrp2 gene do not express the PfHRP2 protein and are, therefore, not identifiable by PfHRP2-detecting RDTs. We evaluated the performance of the SD Bioline Malaria Ag P.f/Pan RDT together with pfhrp2 variation in Madagascar. Genomic DNA isolated from 260 patient blood samples were polymerase chain reaction (PCR)-amplified for the parasite 18S rRNA and pfhrp2 genes. Post-PCR ligation detection reaction-fluorescent microsphere assay (LDR-FMA) was performed for the identification of parasite species. Plasmodium falciparum histidine-rich protein 2 amplicons were sequenced. Polymerase chain reaction diagnosis of patient samples showed that 29% (75/260) were infected and P. falciparum was present in 95% (71/75) of these PCR-positive samples. Comparing RDT and P. falciparum detection by LDR-FMA, eight samples were RDT negative but P. falciparum positive (false negatives), all of which were pfhrp2 positive. The sensitivity and specificity of the RDT were 87% and 90%, respectively. Seventy-three samples were amplified for pfhrp2 , from which nine randomly selected amplicons were sequenced, yielding 13 sequences. Amplification of pfhrp2 , combined with RDT analysis and P. falciparum detection by LDR-FMA, showed that there was no indication of pfhrp2 deletion. Sequence analysis of pfhrp2 showed that the correlation between pfhrp2 sequence structure and RDT detection rates was unclear. Although the observed absence of pfhrp2 deletion from the samples screened here is encouraging, continued monitoring of the efficacy of the SD Bioline Malaria Ag P.f/Pan RDT for malaria diagnosis in Madagascar is warranted.

An Overview of the Swinburne Online Astronomy Courses

NASA Astrophysics Data System (ADS)

Dempsey, F.

2013-06-01

(Abstract only) An overview of the online astronomy courses at Swinburne University of Technology is presented for the benefit of AAVSO members who might be interested in the courses or programs. The decision to take the online Master's degree in astronomy at Swinburne was a natural evolution from being interested in astronomy at an early age, being an amateur astronomer all my life, and being a variable star observer and member of the AAVSO for the past several decades. This presentation provides an overview of the program and examples of the course materials, assignments, and projects that may provide some idea of the commitment and expectations for AAVSO members considering the program.

The NASA/industry Design Analysis Methods for Vibrations (DAMVIBS) Program: A government overview

NASA Technical Reports Server (NTRS)

Kvaternik, Raymond G.

1992-01-01

LaRC, under the Design Analysis Methods for Vibrations (DAMVIBS) Program, set out in 1984 to establish the technology base needed by the rotorcraft industry for developing an advanced finite-element-based dynamics design analysis capability for vibrations. Considerable work was performed by the industry participants in the program since that time. Because the DAMVIBS Program is being phased out, a government/industry assessment of the program was made to identify those accomplishments and contributions which may be ascribed to the program. The purpose is to provide an overview of the program and its accomplishments and contributions from the perspective of the government sponsoring organization.

Office of the Under Secretary of Defense (Comptroller)

Science.gov Websites

Estimates for FY 2019 (Green Book) PDF icon Excel icon (Zip File) Operations and Maintenance Overview Operation and Maintenance Overview PDF icon Budget Documents Military Personnel Programs (M-1) PDF icon Excel icon - Budget Appendix Display (M-1) Excel icon Operation and Maintenance Programs (O-1) PDF icon

Dropping Out of School. State Programs in Dropout Prevention.

ERIC Educational Resources Information Center

Sherman, Joel D.; Levine, Andrea B.

This document discusses state initiatives to address the dropout problem by presenting an overview of programmatic strategies states are using to meet the needs of dropout-prone youth and school dropouts and strategies to finance these efforts. It provides a framework for understanding current state programs and then presents an overview of…

77 FR 20872 - Intelligent Transportation Systems Program Advisory Committee; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-06

... organization, management, and mission; (5) Overview of the ITS Research Program; and (6) Brief ethics review... welcome new members and to provide the committee an overview of information essential to its functioning..., 2012, was created to advise the Secretary of Transportation on all matters relating to the study...

Research Overview: Implications for Public Policy. Higher Education in TAFE. Monograph Series 01/2009

ERIC Educational Resources Information Center

Moodie, Gavin; Wheelahan, Leesa; Billett, Stephen; Kelly, Ann

2009-01-01

A project funded through the National Vocational Education and Training Research and Evaluation program investigated higher education programs--mostly bachelor's and associate degrees--offered by technical and further education (TAFE) institutes. This overview highlights some of the implications for public policy identified through this project.…

Fundamentals of Title IV Administration: From Applying to Creating Reports, 2003-2004.

ERIC Educational Resources Information Center

Office of Federal Student Aid (ED), Washington, DC.

This document provides a Fundamentals of Title IV Administration Workshop Agenda. The agenda includes an introduction and high level overview: the process in general; history of the programs; laws and regulations; and overview of the programs. Following this is a section on applying to participate and understand your school's responsibilities…

Mars base technology program overview

NASA Technical Reports Server (NTRS)

Chu, Chneg-Chih; Hayati, Samad A.; Udomkesmalee, Suraphol

2005-01-01

In this paper, we present an overview of the current technology portfolio for Mars Base Technology Program. Brief descriptions of the awarded technologies and the high-priority areas in both NRAs are provided to show the current focus of MTP. We also present the approach that MTP uses to evaluate technology maturity for each of the technology tasks.

Laboratory Directed Research and Development Program Assessment for FY 2015

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hatton, Diane; Barkigia, K.; Giacalone, P.

2016-03-01

This report provides an overview of the BNL LDRD program and a summary of the management processes, project peer review, a financial overview, and the relation of the portfolio of LDRD projects to BNL's mission, initiatives, and strategic plan. Also included are a summary of success indicators and a self-assessment.

Overview of U.S. EPA Aging Water Infrastructure Research Program - Interfacing with the Water Industry on Technology Assessment

EPA Science Inventory

This slide presentation summarizes key elements of the EPA Office of Research and Development’s (ORD) Aging Water Infrastructure (AWI) Research program. An overview of the national problems posed by aging water infrastructure is followed by a brief description of EPA’s overall r...

NOAA Office of Exploration and Research > About OER > Program Review

Science.gov Websites

Organization Guiding Documents Organizational Structure Map of Staff and Affiliate Locations Strategic Plan Media News Room OER Symposium Overview Organization Guiding Documents Organizational Structure Map of Program Review Home About OER Overview Organization Guiding Documents Organizational Structure Map of

Structural Equation Modeling (SEM) for Satisfaction and Dissatisfaction Ratings; Multiple Group Invariance Analysis across Scales with Different Response Format

ERIC Educational Resources Information Center

Mazaheri, Mehrdad; Theuns, Peter

2009-01-01

The current study evaluates three hypothesized models on subjective well-being, comprising life domain ratings (LDR), overall satisfaction with life (OSWL), and overall dissatisfaction with life (ODWL), using structural equation modeling (SEM). A sample of 1,310 volunteering students, randomly assigned to six conditions, rated their overall life…

76 FR 74709 - Hazardous Waste Management System; Identification and Listing of Hazardous Waste; Final Exclusion

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-01

... stated that ExxonMobil's waste is not subject to the LDR standards, because the waste was not delisted at the point of generation, ExxonMobil may submit a variance to the treatment standards as described in... granting a petition submitted by ExxonMobil Refining and Supply Company--Beaumont Refinery (Beaumont...

NASA/FAA Tailplane Icing Program Overview

NASA Technical Reports Server (NTRS)

Ratvasky, Thomas P.; VanZante, Judith Foss; Riley, James T.

1999-01-01

The effects of tailplane icing were investigated in a four-year NASA/FAA Tailplane Icing, Program (TIP). This research program was developed to improve the understanding, of iced tailplane aeroperformance and aircraft aerodynamics, and to develop design and training aides to help reduce the number of incidents and accidents caused by tailplane icing. To do this, the TIP was constructed with elements that included icing, wind tunnel testing, dry-air aerodynamic wind tunnel testing, flight tests, and analytical code development. This paper provides an overview of the entire program demonstrating the interconnectivity of the program elements and reports on current accomplishments.

Air Force Phillips Laboratory Battery Program overview

NASA Technical Reports Server (NTRS)

House, Shaun

1992-01-01

Battery development and testing efforts at Phillips Laboratory fall into three main categories: nickel hydrogen, sodium sulfur, and solid state batteries. Nickel hydrogen work is broken down into a Low Earth Orbit (LEO) Life Test Program, a LEO Pulse Test Program, and a Hydrogen Embrittlement Investigation. Sodium sulfur work is broken down into a Geosynchronous Earth Orbit (GEO) Battery Flight Test and a Hot Launch Evaluation. Solid state polymer battery work consists of a GEO Battery Development Program, a Pulse Power Battery Small Business Innovation Research (SBIR), and an in-house evaluation of current generation laboratory cells. An overview of the program is presented.

Overview of drug and alcohol use among large truck and bus drivers, 2011–13.

DOT National Transportation Integrated Search

2016-12-01

This report provides a broad overview of drug and alcohol usage among large truck and bus drivers for 201113. Data sources for the overview are: testing results from motor carrier drug testing programs, roadside inspections on large trucks and bus...

Dryden Flight Research Center: Center Overview

NASA Technical Reports Server (NTRS)

Ratnayake, Nalin

2009-01-01

This viewgraph presentation describes a general overview of Dryden Flight Research Center. Strategic partnerships, Dryden's mission activity, exploration systems and aeronautics research programs are also described.

NASA Launch Services Program Overview

NASA Technical Reports Server (NTRS)

Higginbotham, Scott

2016-01-01

The National Aeronautics and Space Administration (NASA) has need to procure a variety of launch vehicles and services for its unmanned spacecraft. The Launch Services Program (LSP) provides the Agency with a single focus for the acquisition and management of Expendable Launch Vehicle (ELV) launch services. This presentation will provide an overview of the LSP and its organization, approach, and activities.

A Fifty-State Survey of School Finance Policies and Programs: An Overview

ERIC Educational Resources Information Center

Verstegen, Deborah A.; Jordan, Teresa S.

2009-01-01

This overview provides a synthesis of a comprehensive survey of school finance programs in the 50 states conducted in 2006-07. Information was provided by chief state school finance officers or persons with expertise in a state's public school funding-allocation system. Brief descriptions of the major Pre-K-12 funding formulae, district-based…

Review of Interventions in the Field of Prevention of Adolescent Pregnancy. Preliminary Report.

ERIC Educational Resources Information Center

Dryfoos, Joy G.

This report presents an overview of programs that may have a potential for prevention of teenage pregnancy. The report starts with a summary of expert opinions on the dimensions of and solutions to the problem and then describes several relatively successful programs. Following this is an overview of interventions with an analysis of program…

Overview Presentation

NASA Technical Reports Server (NTRS)

Lytle, John

2001-01-01

This report provides an overview presentation of the 2000 NPSS (Numerical Propulsion System Simulation) Review and Planning Meeting. Topics include: 1) a background of the program; 2) 1999 Industry Feedback; 3) FY00 Status, including resource distribution and major accomplishments; 4) FY01 Major Milestones; and 5) Future direction for the program. Specifically, simulation environment/production software and NPSS CORBA Security Development are discussed.

2012 NASA Range Safety Annual Report

NASA Technical Reports Server (NTRS)

Dumont, Alan G.

2012-01-01

This report provides a NASA Range Safety (NRS) overview for current and potential range users. This report contains articles which cover a variety of subject areas, summaries of various NASA Range Safety Program (RSP) activities performed during the past year, links to past reports, and information on several projects that may have a profound impact on the way business will be conducted in the future. Specific topics discussed in the 2012 NASA Range Safety Annual Report include a program overview and 2012 highlights; Range Safety Training; Independent Assessments; Support to Program Operations at all ranges conducting NASA launch/flight operations; a continuing overview of emerging range safety-related technologies; and status reports from all of the NASA Centers that have Range Safety responsibilities.

The NASA/industry Design Analysis Methods for Vibrations (DAMVIBS) program: A government overview

NASA Technical Reports Server (NTRS)

Kvaternik, Raymond G.

1993-01-01

NASA-Langley, under the Design Analysis Methods for Vibrations (DAMVIBS) Program, set out in 1984 to establish the technology base needed by the rotorcraft industry for developing an advanced finite-element-based dynamics design analysis capability for vibrations. Considerable work has been done by the industry participants in the program since that time. Because the DAMVIBS Program is being phased out, a government/industry assessment of the program has been made to identify those accomplishments and contributions which may be ascribed to the program. The purpose of this paper is to provide an overview of the program and its accomplishments and contributions from the perspective of the government sponsoring organization.

Disability Overview

MedlinePlus

... About CDC.gov . Disability & Health Home Disability Overview Disability Inclusion Barriers to Inclusion Inclusion Strategies Inclusion in Programs & Activities Resources Healthy Living Disability & Physical Activity Disability & Obesity Disability & Smoking Disability & Breast ...

An Overview of Video Description: History, Benefits, and Guidelines

ERIC Educational Resources Information Center

Packer, Jaclyn; Vizenor, Katie; Miele, Joshua A.

2015-01-01

This article provides an overview of the historical context in which video description services have evolved in the United States, a summary of research demonstrating benefits to people with vision loss, an overview of current video description guidelines, and information about current software programs that are available to produce video…

Essentials of Pediatric Emergency Medicine Fellowship: Part 1: An Overview.

PubMed

Zaveri, Pavan P; Hsu, Deborah; Mittiga, Matthew R; Wolff, Margaret; Reynolds, Stacy; Kim, In; Allen, Coburn; McAneney, Constance M; Kou, Maybelle

2016-05-01

This article is the first in a 7-part series (Table 1) that aims to comprehensively describe the current state and future directions of pediatric emergency medicine fellowship training from the essential requirements to considerations for successfully administering and managing a program to the careers that may be anticipated on program completion. This overview article provides a framework for the series.

Distance Education for Doctoral Students: An Overview of the National Cluster Format for Students in the Doctoral Program for Child and Youth Studies.

ERIC Educational Resources Information Center

Hesser, Lois Ann

This paper offers an overview of the telecommunications and delivery techniques involved in providing distance education to graduate students in doctoral programs. Good distance education should ensure variety of format and successful communication; it can come via audiobridge, videotapes, audiotapes, the telephone, electronic mail, electronic…

Overview of Training Practices Incorporating Adult Learning. Selected Federal Legislation and Programs Relating to Adult Learning.

ERIC Educational Resources Information Center

American Univ., Washington, DC. Adult Learning Potential Inst.

This document--a survey identifying federal legislation and programs that in some way address the adult learner--is one in a series of four developed to provide a comprehensive overview of the scope of training practices relating to adult learning. It provides a panoramic view of adult learning in response to national priorities based upon…

Public-Private Partnerships in Defense Acquisition Programs-Defensible?

DTIC Science & Technology

2009-12-01

1 B. DEFINING AND DIFFERENTIATING PPPS.............................................1 C. OVERVIEW OF GLOBAL PPP...is followed by an overview of the global movement of PPPs, with primary focus on defense PPPs. Next, the evolution of research themes on PPPs from...programs. The term, “PFIs” is commonly used interchangeably with PPPs.3 Today, PFIs dominate the global PPPs arena (Broadbent & Laughlin, 2003) and

Global Security Contingency Fund: Summary and Issue Overview

DTIC Science & Technology

2014-04-04

Diplomacy and Development Review (QDDR), Washington, D.C., December 2010, p. 203; Gordon Adams and Rebecca Williams, A New Way Forward: Rebalancing ...Williams, A New Way Forward: Rebalancing Security Assistance Programs and (continued...) Global Security Contingency Fund: Summary and Issue Overview...a large security assistance portfolio . But others may point to the State Department’s creation of new programs under the Security Assistance

Perception as a key component in the development of fire affected land in Eastern Spain. El Massís del Caroig study case

NASA Astrophysics Data System (ADS)

Cerdà, Artemi; Pereira, Paulo; Borja, Manuel Estaban Lucas; Keesstra, Saskia; Úbeda, Xavier; Francisco Martínez Murillo, Juan; Muñoz Rojas, Miriam; Oliva, Marc; Novara, Agata

2017-04-01

Land Degradation needs biophysical and socioeconomic research approaches to understand the processes that alter the natural ecosystems by the human societies. Both approaches are relevant also to achieve the development of the societies and reach the sustainability of the land management (Escadafal et al., 2015; Jafari and Bakhshandehmehr, 2016). The opinion of the citizens, their perception of the land degradation and the chances we have to built more sustainable management and societies is less researched than other topics such as soil erosion, climate change, water contamination or lost of biodiversity (Francos et al., 2016; Keesstra et al., 2016; Martínez Murilloet al., 2016; Muñoz Rojas et al., 2016; Ruiz-Fernández et al, 2016; ). Forest fires are part of the Earth System since the plant colonization of the continents, fire is present in all the human societies and fire contributed to shape ecosystems. However, a negative opinion about the fire is found in many modern societies (Marques et al., 2015; Assefa and Hans-Rudolf, 2016; Orchard et al., 2016; Pereira et al., 2016). Forest fires are not a new issue in the Mediterranean due to the traditional use for grazing, agriculture or hunting, but the wildfires are generalized since the abandonment of the land in the last century. The lost of rural population and the mechanisation resulted in a vegetation recovery that triggered large wildfires in the whole North Mediterranean since the 1970´s. The perception of the forest fires by the citizens is very negative in El Massís del Caroig. Since 2012 until 2015 a questionnaire was applied to 188 stakeholders in the region and the results demonstrate that the prescribed fires are negative for any group of the society and they reject the use of prescribed fires. Fire is seen as a problem. Acknowledgements The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement n 603498 (RECARE project) and the CGL2013- 47862-C2-1-R and CGL2016-75178-C2-2-R national research projects. References Assefa, E., & Hans-Rudolf, B. (2016). Farmers' perception of land degradation and traditional knowledge in southern Ethiopia—Resilience and stability. Land Degradation and Development, 27(6), 1552-1561. doi:10.1002/ldr.2364 Escadafal, R., Barbero-Sierra, C., Exbrayat, W., Marques, M. J., Akhtar-Schuster, M., El Haddadi, A., & Ruiz, M. (2015). First appraisal of the current structure of research on land and soil degradation as evidenced by bibliometric analysis of publications on desertification. Land Degradation and Development, 26(5), 413-422. doi:10.1002/ldr.2351 Francos, M., Úbeda, X., Tort, J., Panareda, J.M., Cerdà, A. 2016. The role of forest fire severity on vegetation recovery after 18 years. Implications for forest management of Quercus suber L. in Iberian Peninsula, Global and Planetary Change,145:11-16. http://dx.doi.org/10.1016/j.gloplacha.2016.07.016 Hedo, J., Lucas-Borja, M.E., Wic, C., Andrés-Abellán, M., De Las Heras, J. Soil microbiological properties and enzymatic activities of long-term post-fire recovery in dry and semiarid Aleppo pine (Pinus halepensis M.) forest stands. (2015) Solid Earth, 6 (1), pp. 243-252. DOI: http://dx.doi.org/10.5194/se-6-243-2015 Jafari, R., & Bakhshandehmehr, L. (2016). Quantitative mapping and assessment of environmentally sensitive areas to desertification in central iran. Land Degradation and Development, 27(2), 108-119. doi:10.1002/ldr.2227 Keesstra S, Wittenberg L, Maroulis J, Sambalino F, Malkinson D, Cerdà A, Pereira P. 2016. The influence of fire history, plant species and post-fire management on soil water repellency in a Mediterranean catchment: The Mount Carmel range, Israel. Catena, 149, 857-866. DOI: 10.1016/j.catena.2016.04.006 Marques, M. J., Bienes, R., Cuadrado, J., Ruiz-Colmenero, M., Barbero-Sierra, C., & Velasco, A. (2015). Analysing perceptions attitudes and responses of winegrowers about sustainable land management in central spain. Land Degradation and Development, 26(5), 458-467. doi:10.1002/ldr.2355 Martínez-Murillo, J. F., Hueso-González, P., Ruiz-Sinoga, J. D., & Lavee, H. (2016). Short-term experimental fire effects in soil and water losses in southern of spain. Land Degradation and Development, 27(5), 1513-1522. doi:10.1002/ldr.2504 Muñoz-Rojas, M., Erickson, T.E., Martini, D., Dixon, K.D., Merritt, D.J (2016) Soil physicochemical and microbiological indicators of short, medium and long term post-fire recovery in semi-arid ecosystems. Ecological indicators 63, 14-22, doi: 10.1016/j.ecolind.2015.11.038 Orchard, S. E., Stringer, L. C., & Manyatsi, A. M. (2016). Farmer perceptions and responses to soil degradation in swaziland. Land Degradation and Development, doi:10.1002/ldr.2595 Pereira, P., Mierauskas, P., & Novara, A. (2016). Stakeholders' perceptions about fire impacts on lithuanian protected areas. Land Degradation and Development, 27(4), 871-883. doi:10.1002/ldr.2290 Ruiz-Fernández, J.; Nieuwendam, A.; Oliva, M.; Lopes, V.; Cruces, A. Janeiro, A.; Freitas, C. & López-Sáez, J.A (2016). Cryogenic processes and fire activity in a high Atlantic mountain area in NW Iberia (Picos de Europa) during the Mid-Late Holocene. Science of the Total Environment, doi: 10.1016/j.scitotenv.2016.03.022.

Fatigue and fracture: Overview

NASA Technical Reports Server (NTRS)

Halford, G. R.

1984-01-01

A brief overview of the status of the fatigue and fracture programs is given. The programs involve the development of appropriate analytic material behavior models for cyclic stress-strain-temperature-time/cyclic crack initiation, and cyclic crack propagation. The underlying thrust of these programs is the development and verification of workable engineering methods for the calculation, in advance of service, of the local cyclic stress-strain response at the critical life governing location in hot section compounds, and the resultant crack initiation and crack growth lifetimes.

Space Shuttle Reusable Solid Rocket Motor Program Overview and Lessons Learned

NASA Technical Reports Server (NTRS)

Graves, Stan R.; McCool, Alex (Technical Monitor)

2001-01-01

An overview of the Space Shuttle Reusable Solid Rocket Motor (RSRM) program is provided with a summary of lessons learned since the first test firing in 1977. Fifteen different lessons learned are discussed that fundamentally changed the motor's design, processing, and RSRM program risk management systems. The evolution of the rocket motor design is presented including the baseline or High Performance Solid Rocket Motor (HPM), the Filament Wound Case (FWC), the RSRM, and the proposed Five-Segment Booster (FSB).

Demonstrating Robotic Autonomy in NASA's Intelligent Systems Project

NASA Technical Reports Server (NTRS)

Morris, Robert; Smith, Ben; Estlin, Tara; Pedersen, Liam

2004-01-01

This paper will provide an overview of NASA's investments in autonomy during the past five years within the Intelligent Systems Project, with particular attention paid to investments that have resulted in mission infusion of autonomy technology, in particular, into the recent Mars Exploration Rover (MER) mission. The content of the paper will be divided into two primary topic areas: a technical overview of the component technologies developed under the program, and a programmatic overview of the history and organization of the NASA IS project itself, with a focus on describing the program elements related to autonomy and intelligent robotics. The paper will also provide an overview of the September 2004 autonomy demonstrations, including a discussion of objectives, organization, and preliminary results (to the extent they are available before the submission deadline).

Proposed Site Treatment Plan (PSTP). Volumes 1 and 2 and Reference Document

DOE Office of Scientific and Technical Information (OSTI.GOV)

Helmich, E.; Noller, D.K.; Wierzbicki, K.S.

1994-12-22

The Compliance Plan Volume provides overall schedules with target dates for achieving compliance with the land disposal restrictions (LDR) and contains procedures to establish milestones to be enforced under the Order. Information regarding the technical evaluation of treatment options for SRS mixed wastes is contained in the Background Volume and is provided for informational purposes only.

The Effect of a Reading Accommodation on Standardized Test Scores of Learning Disabled and Non Learning Disabled Students.

ERIC Educational Resources Information Center

Meloy, Linda L.; Deville, Craig; Frisbie, David

The effect of the Read Aloud accommodation on the performances of learning disabled in reading (LD-R) and non-learning disabled (non LD) middle school students was studied using selected texts from the Iowa Tests of Basic Skills (ITBS) achievement battery. Science, Usage and Expression, Math Problem Solving and Data Interpretation, and Reading…