A clinical study of lung cancer dose calculation accuracy with Monte Carlo simulation.
Zhao, Yanqun; Qi, Guohai; Yin, Gang; Wang, Xianliang; Wang, Pei; Li, Jian; Xiao, Mingyong; Li, Jie; Kang, Shengwei; Liao, Xiongfei
2014-12-16
The accuracy of dose calculation is crucial to the quality of treatment planning and, consequently, to the dose delivered to patients undergoing radiation therapy. Current general calculation algorithms such as Pencil Beam Convolution (PBC) and Collapsed Cone Convolution (CCC) have shortcomings in regard to severe inhomogeneities, particularly in those regions where charged particle equilibrium does not hold. The aim of this study was to evaluate the accuracy of the PBC and CCC algorithms in lung cancer radiotherapy using Monte Carlo (MC) technology. Four treatment plans were designed using Oncentra Masterplan TPS for each patient. Two intensity-modulated radiation therapy (IMRT) plans were developed using the PBC and CCC algorithms, and two three-dimensional conformal therapy (3DCRT) plans were developed using the PBC and CCC algorithms. The DICOM-RT files of the treatment plans were exported to the Monte Carlo system to recalculate. The dose distributions of GTV, PTV and ipsilateral lung calculated by the TPS and MC were compared. For 3DCRT and IMRT plans, the mean dose differences for GTV between the CCC and MC increased with decreasing of the GTV volume. For IMRT, the mean dose differences were found to be higher than that of 3DCRT. The CCC algorithm overestimated the GTV mean dose by approximately 3% for IMRT. For 3DCRT plans, when the volume of the GTV was greater than 100 cm(3), the mean doses calculated by CCC and MC almost have no difference. PBC shows large deviations from the MC algorithm. For the dose to the ipsilateral lung, the CCC algorithm overestimated the dose to the entire lung, and the PBC algorithm overestimated V20 but underestimated V5; the difference in V10 was not statistically significant. PBC substantially overestimates the dose to the tumour, but the CCC is similar to the MC simulation. It is recommended that the treatment plans for lung cancer be developed using an advanced dose calculation algorithm other than PBC. MC can accurately calculate the dose distribution in lung cancer and can provide a notably effective tool for benchmarking the performance of other dose calculation algorithms within patients.
Shin, H-J; Song, J H; Jung, J-Y; Kwak, Y-K; Kay, C S; Kang, Y-N; Choi, B O; Jang, H S
2013-01-01
Objective: To evaluate the accuracy of pencil beam calculation (PBC) and Monte Carlo calculation (MCC) for dynamic arc therapy (DAT) in a cylindrically shaped homogenous phantom, by comparing the two plans with an ion chamber, a film and a three-dimensional (3D) volumetric dosemeter. Methods: For this study, an in-house phantom was constructed, and the PBC and MCC plans for DAT were performed using iPlan® RT (BrainLAB®, Heimstetten, Germany). The A16 micro ion chamber (Standard Imaging, Middleton, WI), Gafchromic® EBT2 film (International Specialty Products, Wayne, NJ) and ArcCHECK™ (Sun Nuclear, Melbourne, FL) were used for measurements. For comparison with each plan, two-dimensional (2D) and 3D gamma analyses were performed using 3%/3 mm and 2%/2 mm criteria. Results: The difference between the PBC and MCC plans using 2D and 3D gamma analyses was found to be 7.85% and 28.8%, respectively. The ion chamber and 2D dose distribution measurements did not exhibit this difference revealed by the comparison between the PBC and MCC plans. However, the 3D assessment showed a significant difference between the PBC and MCC (62.7% for PBC vs 93.4% for MCC, p = 0.034). Conclusion: Evaluation using a 3D volumetric dosemeter can be clinically useful for delivery quality assurance (QA), and the MCC should be used to achieve the most reliable dose calculation for DAT. Advances in knowledge: (1) The DAT plan calculated using the PBC has a limitation in the calculation methods, and a 3D volumetric dosemeter was found to be an adequate tool for delivery QA of DAT. (2) The MCC was superior to PBC in terms of the accuracy in dose calculation for DAT even in the homogenous condition. PMID:24234583
NASA Astrophysics Data System (ADS)
Woon, Y. L.; Heng, S. P.; Wong, J. H. D.; Ung, N. M.
2016-03-01
Inhomogeneity correction is recommended for accurate dose calculation in radiotherapy treatment planning since human body are highly inhomogeneous with the presence of bones and air cavities. However, each dose calculation algorithm has its own limitations. This study is to assess the accuracy of five algorithms that are currently implemented for treatment planning, including pencil beam convolution (PBC), superposition (SP), anisotropic analytical algorithm (AAA), Monte Carlo (MC) and Acuros XB (AXB). The calculated dose was compared with the measured dose using radiochromic film (Gafchromic EBT2) in inhomogeneous phantoms. In addition, the dosimetric impact of different algorithms on intensity modulated radiotherapy (IMRT) was studied for head and neck region. MC had the best agreement with the measured percentage depth dose (PDD) within the inhomogeneous region. This was followed by AXB, AAA, SP and PBC. For IMRT planning, MC algorithm is recommended for treatment planning in preference to PBC and SP. The MC and AXB algorithms were found to have better accuracy in terms of inhomogeneity correction and should be used for tumour volume within the proximity of inhomogeneous structures.
Superficial dose evaluation of four dose calculation algorithms
NASA Astrophysics Data System (ADS)
Cao, Ying; Yang, Xiaoyu; Yang, Zhen; Qiu, Xiaoping; Lv, Zhiping; Lei, Mingjun; Liu, Gui; Zhang, Zijian; Hu, Yongmei
2017-08-01
Accurate superficial dose calculation is of major importance because of the skin toxicity in radiotherapy, especially within the initial 2 mm depth being considered more clinically relevant. The aim of this study is to evaluate superficial dose calculation accuracy of four commonly used algorithms in commercially available treatment planning systems (TPS) by Monte Carlo (MC) simulation and film measurements. The superficial dose in a simple geometrical phantom with size of 30 cm×30 cm×30 cm was calculated by PBC (Pencil Beam Convolution), AAA (Analytical Anisotropic Algorithm), AXB (Acuros XB) in Eclipse system and CCC (Collapsed Cone Convolution) in Raystation system under the conditions of source to surface distance (SSD) of 100 cm and field size (FS) of 10×10 cm2. EGSnrc (BEAMnrc/DOSXYZnrc) program was performed to simulate the central axis dose distribution of Varian Trilogy accelerator, combined with measurements of superficial dose distribution by an extrapolation method of multilayer radiochromic films, to estimate the dose calculation accuracy of four algorithms in the superficial region which was recommended in detail by the ICRU (International Commission on Radiation Units and Measurement) and the ICRP (International Commission on Radiological Protection). In superficial region, good agreement was achieved between MC simulation and film extrapolation method, with the mean differences less than 1%, 2% and 5% for 0°, 30° and 60°, respectively. The relative skin dose errors were 0.84%, 1.88% and 3.90%; the mean dose discrepancies (0°, 30° and 60°) between each of four algorithms and MC simulation were (2.41±1.55%, 3.11±2.40%, and 1.53±1.05%), (3.09±3.00%, 3.10±3.01%, and 3.77±3.59%), (3.16±1.50%, 8.70±2.84%, and 18.20±4.10%) and (14.45±4.66%, 10.74±4.54%, and 3.34±3.26%) for AXB, CCC, AAA and PBC respectively. Monte Carlo simulation verified the feasibility of the superficial dose measurements by multilayer Gafchromic films. And the rank of superficial dose calculation accuracy of four algorithms was AXB>CCC>AAA>PBC. Care should be taken when using the AAA and PBC algorithms in the superficial dose calculation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thiyagarajan, Rajesh; Vikraman, S; Karrthick, KP
Purpose: To evaluate the impact of dose calculation algorithm on the dose distribution of biologically optimized Volumatric Modulated Arc Therapy (VMAT) plans for Esophgeal cancer. Methods: Eighteen retrospectively treated patients with carcinoma esophagus were studied. VMAT plans were optimized using biological objectives in Monaco (5.0) TPS for 6MV photon beam (Elekta Infinity). These plans were calculated for final dose using Monte Carlo (MC), Collapsed Cone Convolution (CCC) & Pencil Beam Convolution (PBC) algorithms from Monaco and Oncentra Masterplan TPS. A dose grid of 2mm was used for all algorithms and 1% per plan uncertainty maintained for MC calculation. MC basedmore » calculations were considered as the reference for CCC & PBC. Dose volume histogram (DVH) indices (D95, D98, D50 etc) of Target (PTV) and critical structures were compared to study the impact of all three algorithms. Results: Beam models were consistent with measured data. The mean difference observed in reference with MC calculation for D98, D95, D50 & D2 of PTV were 0.37%, −0.21%, 1.51% & 1.18% respectively for CCC and 3.28%, 2.75%, 3.61% & 3.08% for PBC. Heart D25 mean difference was 4.94% & 11.21% for CCC and PBC respectively. Lung Dmean mean difference was 1.5% (CCC) and 4.1% (PBC). Spinal cord D2 mean difference was 2.35% (CCC) and 3.98% (PBC). Similar differences were observed for liver and kidneys. The overall mean difference found for target and critical structures was 0.71±1.52%, 2.71±3.10% for CCC and 3.18±1.55%, 6.61±5.1% for PBC respectively. Conclusion: We observed a significant overestimate of dose distribution by CCC and PBC as compared to MC. The dose prediction of CCC is closer (<3%) to MC than that of PBC. This can be attributed to poor performance of CCC and PBC in inhomogeneous regions around esophagus. CCC can be considered as an alternate in the absence of MC algorithm.« less
Nguyen, Henry H; Shaheen, Abdel Aziz; Baeza, Natalia; Lytvyak, Ellina; Urbanski, Stefan J; Mason, Andrew L; Norman, Gary L; Fritzler, Marvin J; Swain, Mark G
2018-01-01
Up to 20% of Primary Biliary Cholangitis (PBC) patients are estimated to have features that overlap with Autoimmune Hepatitis (AIH). Patients with PBC-AIH overlap syndrome (PBC-AIH OS) have been reported to exhibit suboptimal responses to ursodeoxycholic acid therapy, and are more likely to progress to cirrhosis. Anti-double stranded DNA (anti-dsDNA) and anti-p53 have been previously suggested to be potential autoantibodies for identifying patients with PBC-AIH OS. In our well defined PBC patient cohorts, a comprehensive assessment of various classical and novel autoantibodies was evaluated for their utility in identifying PBC-AIH OS patients. PBC-AIH OS was classified according to the Paris criteria and PBC as per the European Association for the Study of the Liver guidelines. Biobanked serum samples from 197 patients at the University of Calgary Liver Unit and the University of Alberta were analyzed for classical and novel autoantibodies. Anti-dsDNA was measured by the Crithidia luciliae immunofluorescence (CLIFT) assay (1:20 dilution) and chemiluminescence (CIA: QUANTA Flash®, Inova Diagnostics, San Diego). Anti-p53, anti-Ro52/TRIM21, anti-YB 1, anti-GW182, anti-Ge-1, and anti-Ago 2 were measured by either an addressable laser bead immunoassay (ALBIA) or line immunoassay (LIA). Autoantibodies against MIT3, gp210, sp100, LKM1, SLA, and the novel autoantibodies Hexokinase-1 (HK-1), and Kelch like protein 12 (KLHL-12) were measured using QUANTA Lite® ELISA assays. We applied non-parametric methods to compare the biomarkers frequencies between study groups. We used multivariate adjusted models and AUROC to compare the diagnostic accuracy of the different autoantibodies alone or in combination with serum biochemistry. 16 out of 197 PBC patients (8.1%) were classified as PBC-AIH OS. Compared to PBC patients, PBC-AIH OS patients were similar in age (median: 59 vs. 63, P = 0.21) and female predominance (94% vs. 89%, P = 1.00). Anti-dsDNA-by CLIFT (37.5% in PBC-AIH OS vs 9.9% in PBC alone, P <0.01) was the only autoantibody associated with PBC-AIH OS; a finding consistent with previous reports. Significant elevation in serum ALT (62 IU/L in PBC-AIH OS vs 37 IU/L in PBC alone, P < 0.01), and serum IgG (17.6 g/L in OS vs 12.1 g/L in PBC alone, P <0.01) were observed in patients with PBC-AIH OS receiving medical/immunosuppressive therapy. In a multivariate model, positive anti-dsDNA by CLIFT, ALT and IgG were significant predictors of PBC-AIH OS with an area under the receiver operator curve (AUROC) value of 0.84. Consistent with previous findings, the presence of anti-dsDNA by CLIFT is associated with PBC-AIH OS. Contrary to previous reports, anti-p53 was not associated with PBC-AIH OS. Our comprehensive evaluation of various classical and novel autoantibody biomarkers including Ro52/TRIM21, anti-p53, anti-KLHL-12 and anti-HK-1 were not significantly associated with PBC-AIH OS. Our findings highlight the ongoing need for the research and development of new autoantibody biomarkers to aid in the diagnosis of PBC-AIH OS.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Iwai, P; Lins, L Nadler
Purpose: There is a lack of studies with significant cohort data about patients using pacemaker (PM), implanted cardioverter defibrillator (ICD) or cardiac resynchronization therapy (CRT) device undergoing radiotherapy. There is no literature comparing the cumulative doses delivered to those cardiac implanted electronic devices (CIED) calculated by different algorithms neither studies comparing doses with heterogeneity correction or not. The aim of this study was to evaluate the influence of the algorithms Pencil Beam Convolution (PBC), Analytical Anisotropic Algorithm (AAA) and Acuros XB (AXB) as well as heterogeneity correction on risk categorization of patients. Methods: A retrospective analysis of 19 3DCRT ormore » IMRT plans of 17 patients was conducted, calculating the dose delivered to CIED using three different calculation algorithms. Doses were evaluated with and without heterogeneity correction for comparison. Risk categorization of the patients was based on their CIED dependency and cumulative dose in the devices. Results: Total estimated doses at CIED calculated by AAA or AXB were higher than those calculated by PBC in 56% of the cases. In average, the doses at CIED calculated by AAA and AXB were higher than those calculated by PBC (29% and 4% higher, respectively). The maximum difference of doses calculated by each algorithm was about 1 Gy, either using heterogeneity correction or not. Values of maximum dose calculated with heterogeneity correction showed that dose at CIED was at least equal or higher in 84% of the cases with PBC, 77% with AAA and 67% with AXB than dose obtained with no heterogeneity correction. Conclusion: The dose calculation algorithm and heterogeneity correction did not change the risk categorization. Since higher estimated doses delivered to CIED do not compromise treatment precautions to be taken, it’s recommend that the most sophisticated algorithm available should be used to predict dose at the CIED using heterogeneity correction.« less
First-Principle Construction of U(1) Symmetric Matrix Product States
NASA Astrophysics Data System (ADS)
Rakov, Mykhailo V.
2018-07-01
The algorithm to calculate the sets of symmetry sectors for virtual indices of U(1) symmetric matrix product states (MPS) is described. The principal differences between open (OBC) and periodic (PBC) boundary conditions are stressed, and the extension of PBC MPS algorithm to projected entangled pair states is outlined.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Çatlı, Serap, E-mail: serapcatli@hotmail.com; Tanır, Güneş
2013-10-01
The present study aimed to investigate the effects of titanium, titanium alloy, and stainless steel hip prostheses on dose distribution based on the Monte Carlo simulation method, as well as the accuracy of the Eclipse treatment planning system (TPS) at 6 and 18 MV photon energies. In the present study the pencil beam convolution (PBC) method implemented in the Eclipse TPS was compared to the Monte Carlo method and ionization chamber measurements. The present findings show that if high-Z material is used in prosthesis, large dose changes can occur due to scattering. The variance in dose observed in the presentmore » study was dependent on material type, density, and atomic number, as well as photon energy; as photon energy increased back scattering decreased. The dose perturbation effect of hip prostheses was significant and could not be predicted accurately by the PBC method for hip prostheses. The findings show that for accurate dose calculation the Monte Carlo-based TPS should be used in patients with hip prostheses.« less
Qin, Baodong; Liang, Yan; Yang, Zaixing; Zhong, Renqian
2012-01-01
Primary biliary cirrhosis (PBC) is a chronic liver disease characterized by intrahepatic bile-duct destruction, cholestasis, and fibrosis. It can lead to cirrhosis and eventually liver failure. PBC also shows some regional differences with respect to incidence and prevalence that are becoming more pronounced each year. Recently, researchers have paid more attention to PBC. To evaluate the development of PBC research during the past 11 years, we determined the quantity and quality of articles on this subject. We also compared the contributions of scientists from the US, UK, Japan, Italy, Germany, and China. The English-language papers covering PBC published in journals from 2000 through 2010 were retrieved from the PubMed database. We recorded the number of papers published each year, analyzed the publication type, and calculated the accumulated, average impact factors (IFs) and citations from every country. The quantity and quality of articles on PBC were compared by country. We also contrasted the level of PBC research in China and other countries. The total number of articles did not significantly increase during the past 11 years. The number of articles from the US exceeded those from any other country; the publications from the US also had the highest IFs and the most citations. Four other countries showed complex trends with respect to the quantity and quality of articles about PBC. The researchers from the US have contributed the most to the development of PBC research. They currently represent the highest level of research. Some high-level studies, such as RCTs, meta-analyses, and in-depth basic studies should be launched. The gap between China and the advanced level is still enormous. Chinese investigators still have a long way to go.
Kapanen, Mika K.; Hyödynmaa, Simo J.; Wigren, Tuija K.; Pitkänen, Maunu A.
2014-01-01
The accuracy of dose calculation is a key challenge in stereotactic body radiotherapy (SBRT) of the lung. We have benchmarked three photon beam dose calculation algorithms — pencil beam convolution (PBC), anisotropic analytical algorithm (AAA), and Acuros XB (AXB) — implemented in a commercial treatment planning system (TPS), Varian Eclipse. Dose distributions from full Monte Carlo (MC) simulations were regarded as a reference. In the first stage, for four patients with central lung tumors, treatment plans using 3D conformal radiotherapy (CRT) technique applying 6 MV photon beams were made using the AXB algorithm, with planning criteria according to the Nordic SBRT study group. The plans were recalculated (with same number of monitor units (MUs) and identical field settings) using BEAMnrc and DOSXYZnrc MC codes. The MC‐calculated dose distributions were compared to corresponding AXB‐calculated dose distributions to assess the accuracy of the AXB algorithm, to which then other TPS algorithms were compared. In the second stage, treatment plans were made for ten patients with 3D CRT technique using both the PBC algorithm and the AAA. The plans were recalculated (with same number of MUs and identical field settings) with the AXB algorithm, then compared to original plans. Throughout the study, the comparisons were made as a function of the size of the planning target volume (PTV), using various dose‐volume histogram (DVH) and other parameters to quantitatively assess the plan quality. In the first stage also, 3D gamma analyses with threshold criteria 3%/3 mm and 2%/2 mm were applied. The AXB‐calculated dose distributions showed relatively high level of agreement in the light of 3D gamma analysis and DVH comparison against the full MC simulation, especially with large PTVs, but, with smaller PTVs, larger discrepancies were found. Gamma agreement index (GAI) values between 95.5% and 99.6% for all the plans with the threshold criteria 3%/3 mm were achieved, but 2%/2 mm threshold criteria showed larger discrepancies. The TPS algorithm comparison results showed large dose discrepancies in the PTV mean dose (D50%), nearly 60%, for the PBC algorithm, and differences of nearly 20% for the AAA, occurring also in the small PTV size range. This work suggests the application of independent plan verification, when the AAA or the AXB algorithm are utilized in lung SBRT having PTVs smaller than 20‐25 cc. The calculated data from this study can be used in converting the SBRT protocols based on type ‘a’ and/or type ‘b’ algorithms for the most recent generation type ‘c’ algorithms, such as the AXB algorithm. PACS numbers: 87.55.‐x, 87.55.D‐, 87.55.K‐, 87.55.kd, 87.55.Qr PMID:24710454
NASA Astrophysics Data System (ADS)
Lonski, P.; Taylor, M. L.; Hackworth, W.; Phipps, A.; Franich, R. D.; Kron, T.
2014-03-01
Different treatment planning system (TPS) algorithms calculate radiation dose in different ways. This work compares measurements made in vivo to the dose calculated at out-of-field locations using three different commercially available algorithms in the Eclipse treatment planning system. LiF: Mg, Cu, P thermoluminescent dosimeter (TLD) chips were placed with 1 cm build-up at six locations on the contralateral side of 5 patients undergoing radiotherapy for breast cancer. TLD readings were compared to calculations of Pencil Beam Convolution (PBC), Anisotropic Analytical Algorithm (AAA) and Acuros XB (XB). AAA predicted zero dose at points beyond 16 cm from the field edge. In the same region PBC returned an unrealistically constant result independent of distance and XB showed good agreement to measured data although consistently underestimated by ~0.1 % of the prescription dose. At points closer to the field edge XB was the superior algorithm, exhibiting agreement with TLD results to within 15 % of measured dose. Both AAA and PBC showed mixed agreement, with overall discrepancies considerably greater than XB. While XB is certainly the preferable algorithm, it should be noted that TPS algorithms in general are not designed to calculate dose at peripheral locations and calculation results in such regions should be treated with caution.
2013-01-01
Purpose Retrospective analysis of 3D clinical treatment plans to investigate qualitative, possible, clinical consequences of the use of PBC versus AAA. Methods The 3D dose distributions of 80 treatment plans at four different tumour sites, produced using PBC algorithm, were recalculated using AAA and the same number of monitor units provided by PBC and clinically delivered to each patient; the consequences of the difference on the dose-effect relations for normal tissue injury were studied by comparing different NTCP model/parameters extracted from a review of published studies. In this study the AAA dose calculation is considered as benchmark data. The paired Student t-test was used for statistical comparison of all results obtained from the use of the two algorithms. Results In the prostate plans, the AAA predicted lower NTCP value (NTCPAAA) for the risk of late rectal bleeding for each of the seven combinations of NTCP parameters, the maximum mean decrease was 2.2%. In the head-and-neck treatments, each combination of parameters used for the risk of xerostemia from irradiation of the parotid glands involved lower NTCPAAA, that varied from 12.8% (sd=3.0%) to 57.5% (sd=4.0%), while when the PBC algorithm was used the NTCPPBC’s ranging was from 15.2% (sd=2.7%) to 63.8% (sd=3.8%), according the combination of parameters used; the differences were statistically significant. Also NTCPAAA regarding the risk of radiation pneumonitis in the lung treatments was found to be lower than NTCPPBC for each of the eight sets of NTCP parameters; the maximum mean decrease was 4.5%. A mean increase of 4.3% was found when the NTCPAAA was calculated by the parameters evaluated from dose distribution calculated by a convolution-superposition (CS) algorithm. A markedly different pattern was observed for the risk relating to the development of pneumonitis following breast treatments: the AAA predicted higher NTCP value. The mean NTCPAAA varied from 0.2% (sd = 0.1%) to 2.1% (sd = 0.3%), while the mean NTCPPBC varied from 0.1% (sd = 0.0%) to 1.8% (sd = 0.2%) depending on the chosen parameters set. Conclusions When the original PBC treatment plans were recalculated using AAA with the same number of monitor units provided by PBC, the NTCPAAA was lower than the NTCPPBC, except for the breast treatments. The NTCP is strongly affected by the wide-ranging values of radiobiological parameters. PMID:23826854
Bufacchi, Antonella; Nardiello, Barbara; Capparella, Roberto; Begnozzi, Luisa
2013-07-04
Retrospective analysis of 3D clinical treatment plans to investigate qualitative, possible, clinical consequences of the use of PBC versus AAA. The 3D dose distributions of 80 treatment plans at four different tumour sites, produced using PBC algorithm, were recalculated using AAA and the same number of monitor units provided by PBC and clinically delivered to each patient; the consequences of the difference on the dose-effect relations for normal tissue injury were studied by comparing different NTCP model/parameters extracted from a review of published studies. In this study the AAA dose calculation is considered as benchmark data. The paired Student t-test was used for statistical comparison of all results obtained from the use of the two algorithms. In the prostate plans, the AAA predicted lower NTCP value (NTCPAAA) for the risk of late rectal bleeding for each of the seven combinations of NTCP parameters, the maximum mean decrease was 2.2%. In the head-and-neck treatments, each combination of parameters used for the risk of xerostemia from irradiation of the parotid glands involved lower NTCPAAA, that varied from 12.8% (sd=3.0%) to 57.5% (sd=4.0%), while when the PBC algorithm was used the NTCPPBC's ranging was from 15.2% (sd=2.7%) to 63.8% (sd=3.8%), according the combination of parameters used; the differences were statistically significant. Also NTCPAAA regarding the risk of radiation pneumonitis in the lung treatments was found to be lower than NTCPPBC for each of the eight sets of NTCP parameters; the maximum mean decrease was 4.5%. A mean increase of 4.3% was found when the NTCPAAA was calculated by the parameters evaluated from dose distribution calculated by a convolution-superposition (CS) algorithm. A markedly different pattern was observed for the risk relating to the development of pneumonitis following breast treatments: the AAA predicted higher NTCP value. The mean NTCPAAA varied from 0.2% (sd = 0.1%) to 2.1% (sd = 0.3%), while the mean NTCPPBC varied from 0.1% (sd = 0.0%) to 1.8% (sd = 0.2%) depending on the chosen parameters set. When the original PBC treatment plans were recalculated using AAA with the same number of monitor units provided by PBC, the NTCPAAA was lower than the NTCPPBC, except for the breast treatments. The NTCP is strongly affected by the wide-ranging values of radiobiological parameters.
Chaikh, Abdulhamid; Balosso, Jacques
2016-12-01
To apply the statistical bootstrap analysis and dosimetric criteria's to assess the change of prescribed dose (PD) for lung cancer to maintain the same clinical results when using new generations of dose calculation algorithms. Nine lung cancer cases were studied. For each patient, three treatment plans were generated using exactly the same beams arrangements. In plan 1, the dose was calculated using pencil beam convolution (PBC) algorithm turning on heterogeneity correction with modified batho (PBC-MB). In plan 2, the dose was calculated using anisotropic analytical algorithm (AAA) and the same PD, as plan 1. In plan 3, the dose was calculated using AAA with monitor units (MUs) obtained from PBC-MB, as input. The dosimetric criteria's include MUs, delivered dose at isocentre (Diso) and calculated dose to 95% of the target volume (D95). The bootstrap method was used to assess the significance of the dose differences and to accurately estimate the 95% confidence interval (95% CI). Wilcoxon and Spearman's rank tests were used to calculate P values and the correlation coefficient (ρ). Statistically significant for dose difference was found using point kernel model. A good correlation was observed between both algorithms types, with ρ>0.9. Using AAA instead of PBC-MB, an adjustment of the PD in the isocentre is suggested. For a given set of patients, we assessed the need to readjust the PD for lung cancer using dosimetric indices and bootstrap statistical method. Thus, if the goal is to keep on with the same clinical results, the PD for lung tumors has to be adjusted with AAA. According to our simulation we suggest to readjust the PD by 5% and an optimization for beam arrangements to better protect the organs at risks (OARs).
NASA Astrophysics Data System (ADS)
Peng, Jiayuan; Zhang, Zhen; Wang, Jiazhou; Xie, Jiang; Chen, Junchao; Hu, Weigang
2015-10-01
GafChromic RTQA2 film is a type of radiochromic film designed for light field and radiation field alignment. The aim of this study is to extend the application of RTQA2 film to the measurement of patient specific quality assurance (QA) fields as a 2D relative dosimeter. Pre-irradiated and post-irradiated RTQA2 films were scanned in reflection mode using a flatbed scanner. A plan-based calibration (PBC) method utilized the mapping information of the calculated dose image and film grayscale image to create a dose versus pixel value calibration model. This model was used to calibrate the film grayscale image to the film relative dose image. The dose agreement between calculated and film dose images were analyzed by gamma analysis. To evaluate the feasibility of this method, eight clinically approved RapidArc cases (one abdomen cancer and seven head-and-neck cancer patients) were tested using this method. Moreover, three MLC gap errors and two MLC transmission errors were introduced to eight Rapidarc cases respectively to test the robustness of this method. The PBC method could overcome the film lot and post-exposure time variations of RTQA2 film to get a good 2D relative dose calibration result. The mean gamma passing rate of eight patients was 97.90% ± 1.7%, which showed good dose consistency between calculated and film dose images. In the error test, the PBC method could over-calibrate the film, which means some dose error in the film would be falsely corrected to keep the dose in film consistent with the dose in the calculated dose image. This would then lead to a false negative result in the gamma analysis. In these cases, the derivative curve of the dose calibration curve would be non-monotonic which would expose the dose abnormality. By using the PBC method, we extended the application of more economical RTQA2 film to patient specific QA. The robustness of the PBC method has been improved by analyzing the monotonicity of the derivative of the calibration curve.
The immunogenetics of primary biliary cirrhosis: A comprehensive review.
Webb, G J; Siminovitch, K A; Hirschfield, G M
2015-11-01
Primary biliary cirrhosis (PBC), a classic autoimmune liver disease, is characterised by a progressive T cell predominant lymphocytic cholangitis, and a serologic pattern of reactivity in the form of specific anti-mitochondrial antibodies (AMA). CD4+ T cells are particularly implicated by PBC's cytokine signature, the presence of CD4+ T cells specific to mitochondrial auto-antigens, the expression of MHC II on injured biliary epithelial cells, and PBC's coincidence with other similar T cell mediated autoimmune conditions. CD4+ T cells are also central to current animal models of PBC, and their transfer typically also transfers disease. The importance of genetic risk to developing PBC is evidenced by a much higher concordance rate in monozygotic than dizygotic twins, increased AMA rates in asymptomatic relatives, and disproportionate rates of disease in siblings of PBC patients, PBC family members and certain genetically defined populations. Recently, high-throughput genetic studies have greatly expanded our understanding of the gene variants underpinning risk for PBC development, so linking genetics and immunology. Here we summarize genetic association data that has emerged from large scale genome-wide association studies and discuss the evidence for the potential functional significance of the individual genes and pathways identified; we particularly highlight associations in the IL-12-STAT4-Th1 pathway. HLA associations and epigenetic effects are specifically considered and individual variants are linked to clinical phenotypes where data exist. We also consider why there is a gap between calculated genetic risk and clinical data: so-called missing heritability, and how immunogenetic observations are being translated to novel therapies. Ultimately whilst genetic risk factors will only account for a proportion of disease risk, ongoing efforts to refine associations and understand biologic links to disease pathways are hoped to drive more rational therapy for patients. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
Raszeja-Wyszomirska, Joanna; Wunsch, Ewa; Krawczyk, Marek; Rigopoulou, Eirini I; Bogdanos, Dimitrios; Milkiewicz, Piotr
2015-06-01
Primary biliary cirrhosis and Primary sclerosing cholangitis are autoimmune cholestatic liver diseases sharing a lot in common, including a significant impairment of patients' health-related quality of life HRQoL HRQoL in PBC is assessed with disease-specific PBC-40 and PBC-27 questionnaires. A PSC-specific questionnaire has not been developed. Neither PBC-40 nor PBC-27s applicability for PSC has been evaluated. We applied these three questionnaires for HRQoL assessment in a large homogenous cohort of PSC patients. This cross-sectional study enrolled 102 Caucasian PSCs and 53 matched healthy controls and measured HRQoL using generic SF-36, and disease-specific (PBC-40/PBC-27) questionnaires. (i) SF-36. Most SF-36 domains were significantly lower in PSCs than controls. Physical Functioning and Mental Component Summary scores were significantly lower in female patients and correlated negatively with age but not with concurrent inflammatory bowel disease. Cirrhosis was associated with lower Physical Functioning, Role Physical, General Health, Vitality and Physical Component Summary. (ii) PBC-40 and PBC-27. Both tools showed similar HRQoL impairment scoring. Fatigue and Cognitive were impaired in female patients. Several correlations existed between HRQoL and laboratory parameters, including cholestatic tests and Itch. Cirrhosis correlated with Other symptoms and Fatigue PBC-40. (iii) PBC-40 vs PBC-27. Strong correlations among most domains of both questionnaires were seen, as well as between (iv) SF-36 vs PBC-40 or SF-36 vs PBC-27. This is the first study directly comparing PBC-40, PBC-27 and SF-36 in PSC. PSC patients, especially females, show HRQoL impairment. PBC-40 and PBC-27 questionnaires could be of potential use for HRQoL assessment in PSC. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
The choice of statistical methods for comparisons of dosimetric data in radiotherapy.
Chaikh, Abdulhamid; Giraud, Jean-Yves; Perrin, Emmanuel; Bresciani, Jean-Pierre; Balosso, Jacques
2014-09-18
Novel irradiation techniques are continuously introduced in radiotherapy to optimize the accuracy, the security and the clinical outcome of treatments. These changes could raise the question of discontinuity in dosimetric presentation and the subsequent need for practice adjustments in case of significant modifications. This study proposes a comprehensive approach to compare different techniques and tests whether their respective dose calculation algorithms give rise to statistically significant differences in the treatment doses for the patient. Statistical investigation principles are presented in the framework of a clinical example based on 62 fields of radiotherapy for lung cancer. The delivered doses in monitor units were calculated using three different dose calculation methods: the reference method accounts the dose without tissues density corrections using Pencil Beam Convolution (PBC) algorithm, whereas new methods calculate the dose with tissues density correction for 1D and 3D using Modified Batho (MB) method and Equivalent Tissue air ratio (ETAR) method, respectively. The normality of the data and the homogeneity of variance between groups were tested using Shapiro-Wilks and Levene test, respectively, then non-parametric statistical tests were performed. Specifically, the dose means estimated by the different calculation methods were compared using Friedman's test and Wilcoxon signed-rank test. In addition, the correlation between the doses calculated by the three methods was assessed using Spearman's rank and Kendall's rank tests. The Friedman's test showed a significant effect on the calculation method for the delivered dose of lung cancer patients (p <0.001). The density correction methods yielded to lower doses as compared to PBC by on average (-5 ± 4.4 SD) for MB and (-4.7 ± 5 SD) for ETAR. Post-hoc Wilcoxon signed-rank test of paired comparisons indicated that the delivered dose was significantly reduced using density-corrected methods as compared to the reference method. Spearman's and Kendall's rank tests indicated a positive correlation between the doses calculated with the different methods. This paper illustrates and justifies the use of statistical tests and graphical representations for dosimetric comparisons in radiotherapy. The statistical analysis shows the significance of dose differences resulting from two or more techniques in radiotherapy.
Efficient crop type mapping based on remote sensing in the Central Valley, California
NASA Astrophysics Data System (ADS)
Zhong, Liheng
Most agricultural systems in California's Central Valley are purposely flexible and intentionally designed to meet the demands of dynamic markets. Agricultural land use is also impacted by climate change and urban development. As a result, crops change annually and semiannually, which makes estimating agricultural water use difficult, especially given the existing method by which agricultural land use is identified and mapped. A minor portion of agricultural land is surveyed annually for land-use type, and every 5 to 8 years the entire valley is completely evaluated. So far no effort has been made to effectively and efficiently identify specific crop types on an annual basis in this area. The potential of satellite imagery to map agricultural land cover and estimate water usage in the Central Valley is explored. Efforts are made to minimize the cost and reduce the time of production during the mapping process. The land use change analysis shows that a remote sensing based mapping method is the only means to map the frequent change of major crop types. The traditional maximum likelihood classification approach is first utilized to map crop types to test the classification capacity of existing algorithms. High accuracy is achieved with sufficient ground truth data for training, and crop maps of moderate quality can be timely produced to facilitate a near-real-time water use estimate. However, the large set of ground truth data required by this method results in high costs in data collection. It is difficult to reduce the cost because a trained classification algorithm is not transferable between different years or different regions. A phenology based classification (PBC) approach is developed which extracts phenological metrics from annual vegetation index profiles and identifies crop types based on these metrics using decision trees. According to the comparison with traditional maximum likelihood classification, this phenology-based approach shows great advantages when the size of the training set is limited by ground truth availability. Once developed, the classifier is able to be applied to different years and a vast area with only a few adjustments according to local agricultural and annual weather conditions. 250 m MODIS imagery is utilized as the main input to the PBC algorithm and displays promising capacity in crop identification in several counties in the Central Valley. A time series of Landsat TM/ETM+ images at a 30 m resolution is necessary in the crop mapping of counties with smaller land parcels, although the processing time is longer. Spectral characteristics are also employed to identify crops in PBC. Spectral signatures are associated with phenological stages instead of imaging dates, which highly increases the stability of the classifier performance and overcomes the problem of over-fitting. Moderate accuracies are achieved by PBC, with confusions mostly within the same crop categories. Based on a quantitative analysis, misclassification in PBC has very trivial impacts on the accuracy of agricultural water use estimate. The cost of the entire PBC procedure is controlled to a very low level, which will enable its usage in routine annual crop mapping in the Central Valley.
Kaya, Vildan; Yildirim, Mustafa; Yazici, Gozde; Gunduz, Seyda; Bozcuk, Hakan; Paydas, Semra
2018-05-26
Background: Triple-negative breast cancer (TNBC) is a sub-group of breast cancers with a particularly poor prognosis. The results of studies investigating the role of platinum-based chemotherapy (PBC) in metastatic TNBC (mTNBC) have been conflicting. In this meta-analysis, our aim was to assess the effectiveness of PBCs for mTNBCs. Methods: The PubMed, Cochrane Controlled Trials Register Databases, and EBSCOhost databases were accessed. The English language was used as the search language and only human studies were included. The Newcastle–Ottawa Quality Assessment Scale and the Jadad scoring system were used to evaluate the quality of the included randomized controlled studies. Results: Seven studies and 1,571 patients were included in this meta-analysis. The pooled hazard ratio (HR) for overall survival (OS), evaluated on the basis of six studies, showed the use of PBC regimes to be related to OS in mTNBCs (HR 0.620; 95% CI 0.513-0.749; p:<0.001). Four studies containing HR and abstract statistics used for HR calculation were included in the meta-analysis for progression-free survival (PFS). The pooled HR again indicated a significant relation (HR, 0.628; 95% CI, 0.501-0.786; p:<0.001). Conclusions: In this meta-analysis, we confirmed that PBC regimes provide OS and PFS advantages compared to non-PBC regimes. The use of PBC regimes could be a good choice in mTNBC patients for better quality of life and survival. Creative Commons Attribution License
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kawai, D; Takahashi, R; Kamima, T
2015-06-15
Purpose: The accuracy of dose distribution depends on treatment planning system especially in heterogeneity-region. The tolerance level (TL) of the secondary check using the independent dose verification may be variable in lung SBRT plans. We conducted a multi-institutional study to evaluate the tolerance level of lung SBRT plans shown in the AAPM TG114. Methods: Five institutes in Japan participated in this study. All of the institutes used a same independent dose verification software program (Simple MU Analysis: SMU, Triangle Product, Ishikawa, JP), which is Clarkson-based and CT images were used to compute radiological path length. Analytical Anisotropic Algorithm (AAA), Pencilmore » Beam Convolution with modified Batho-method (PBC-B) and Adaptive Convolve (AC) were used for lung SBRT planning. A measurement using an ion-chamber was performed in a heterogeneous phantom to compare doses from the three different algorithms and the SMU to the measured dose. In addition to it, a retrospective analysis using clinical lung SBRT plans (547 beams from 77 patients) was conducted to evaluate the confidence limit (CL, Average±2SD) in dose between the three algorithms and the SMU. Results: Compared to the measurement, the AAA showed the larger systematic dose error of 2.9±3.2% than PBC-B and AC. The Clarkson-based SMU showed larger error of 5.8±3.8%. The CLs for clinical plans were 7.7±6.0 % (AAA), 5.3±3.3 % (AC), 5.7±3.4 % (PBC -B), respectively. Conclusion: The TLs from the CLs were evaluated. A Clarkson-based system shows a large systematic variation because of inhomogeneous correction. The AAA showed a significant variation. Thus, we must consider the difference of inhomogeneous correction as well as the dependence of dose calculation engine.« less
Lonski, P; Keehan, S; Siva, S; Pham, D; Franich, R D; Taylor, M L; Kron, T
2017-05-01
To assess out-of-field dose using three different variants of LiF thermoluminescence dosimeters (TLD) for ten patients who underwent stereotactic ablative body radiotherapy (SABR) for primary renal cell carcinoma (RCC) and compare with treatment planning system (TPS) dose calculations. Thermoluminescent dosimeter (TLD) measurements were conducted at 20, 30, 40 and 50cm from isocentre on ten patients undergoing SABR for primary RCC. Three types of high-sensitivity LiF:Mg,Cu,P TLD material with different 6 Li/ 7 Li isotope ratios were used. Patient plans were calculated using Eclipse Anisotropic Analytical Algorithm (AAA) for clinical evaluation and recalculated using Pencil Beam Convolution (PBC) algorithm for comparison. Both AAA and PBC showed diminished accuracy for photon doses at increasing distance out-of-field. At 50cm, measured photon dose was 0.3cGy normalised to a 10Gy prescription on average with only small variation across all patients. This is likely due to the leakage component of the out-of-field dose. The 6 Li-enriched TLD materials showed increased signal attributable to additional neutron contribution. LiF:Mg,Cu,P TLD containing 6 Li is sensitive enough to measure out-of-field dose 50cm from isocentre however will over-estimate the photon component of out-of-field dose in high energy treatments due to the presence of thermal neutrons. 7 Li enriched materials which are insensitive to neutrons are therefore required for accurate photon dosimetry. Neutron signal has been shown here to increase with MUs and is higher for patients treated using certain non coplanar beam arrangements. Further work is required to convert this additional neutron signal to dose. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.
Security-Enhanced Push Button Configuration for Home Smart Control.
Han, Junghee; Park, Taejoon
2017-06-08
With the emergence of smart and converged home services, the need for the secure and easy interplay of various devices has been increased. Push Button Configuration (PBC) is one of the technologies proposed for easy set-up of a secure session between IT and consumer devices. Although the Wi-Fi Direct specification explicitly states that all devices must support the PBC method, its applicability is very limited. This is because the security vulnerability of PBC can be maliciously exploited so that attackers can make illegitimate sessions with consumer devices. To address this problem, this paper proposes a novel Security-enhanced PBC (SePBC) scheme with which we can uncover suspicious or malicious devices. The proposed mechanism has several unique features. First, we develop a secure handshake distance measurement protocol by preventing an adversary sitting outside the region from maliciously manipulating its distance to be fake. Second, it is compatible with the original Wi-Fi PBC without introducing a brand-new methodology. Finally, SePBC uses lightweight operations without CPU-intensive cryptography computation and employs inexpensive H/W. Moreover, it needs to incur little overhead when there is no attack. This paper also designs and implements the proposed SePBC in the real world. Our experimental results and analysis show that the proposed SePBC scheme effectively defeats attacks on PBC while minimizing the modification of the original PBC equipment.
Security-Enhanced Push Button Configuration for Home Smart Control †
Han, Junghee; Park, Taejoon
2017-01-01
With the emergence of smart and converged home services, the need for the secure and easy interplay of various devices has been increased. Push Button Configuration (PBC) is one of the technologies proposed for easy set-up of a secure session between IT and consumer devices. Although the Wi-Fi Direct specification explicitly states that all devices must support the PBC method, its applicability is very limited. This is because the security vulnerability of PBC can be maliciously exploited so that attackers can make illegitimate sessions with consumer devices. To address this problem, this paper proposes a novel Security-enhanced PBC (SePBC) scheme with which we can uncover suspicious or malicious devices. The proposed mechanism has several unique features. First, we develop a secure handshake distance measurement protocol by preventing an adversary sitting outside the region from maliciously manipulating its distance to be fake. Second, it is compatible with the original Wi-Fi PBC without introducing a brand-new methodology. Finally, SePBC uses lightweight operations without CPU-intensive cryptography computation and employs inexpensive H/W. Moreover, it needs to incur little overhead when there is no attack. This paper also designs and implements the proposed SePBC in the real world. Our experimental results and analysis show that the proposed SePBC scheme effectively defeats attacks on PBC while minimizing the modification of the original PBC equipment. PMID:28594370
Influence of different dose calculation algorithms on the estimate of NTCP for lung complications.
Hedin, Emma; Bäck, Anna
2013-09-06
Due to limitations and uncertainties in dose calculation algorithms, different algorithms can predict different dose distributions and dose-volume histograms for the same treatment. This can be a problem when estimating the normal tissue complication probability (NTCP) for patient-specific dose distributions. Published NTCP model parameters are often derived for a different dose calculation algorithm than the one used to calculate the actual dose distribution. The use of algorithm-specific NTCP model parameters can prevent errors caused by differences in dose calculation algorithms. The objective of this work was to determine how to change the NTCP model parameters for lung complications derived for a simple correction-based pencil beam dose calculation algorithm, in order to make them valid for three other common dose calculation algorithms. NTCP was calculated with the relative seriality (RS) and Lyman-Kutcher-Burman (LKB) models. The four dose calculation algorithms used were the pencil beam (PB) and collapsed cone (CC) algorithms employed by Oncentra, and the pencil beam convolution (PBC) and anisotropic analytical algorithm (AAA) employed by Eclipse. Original model parameters for lung complications were taken from four published studies on different grades of pneumonitis, and new algorithm-specific NTCP model parameters were determined. The difference between original and new model parameters was presented in relation to the reported model parameter uncertainties. Three different types of treatments were considered in the study: tangential and locoregional breast cancer treatment and lung cancer treatment. Changing the algorithm without the derivation of new model parameters caused changes in the NTCP value of up to 10 percentage points for the cases studied. Furthermore, the error introduced could be of the same magnitude as the confidence intervals of the calculated NTCP values. The new NTCP model parameters were tabulated as the algorithm was varied from PB to PBC, AAA, or CC. Moving from the PB to the PBC algorithm did not require new model parameters; however, moving from PB to AAA or CC did require a change in the NTCP model parameters, with CC requiring the largest change. It was shown that the new model parameters for a given algorithm are different for the different treatment types.
Zenouzi, Roman; von der Gablentz, Janina; Heldmann, Marcus; Göttlich, Martin; Weiler-Normann, Christina; Sebode, Marcial; Ehlken, Hanno; Hartl, Johannes; Fellbrich, Anja; Siemonsen, Susanne; Schramm, Christoph; Münte, Thomas F; Lohse, Ansgar W
2018-01-01
In primary biliary cholangitis (PBC) fatigue is a major clinical challenge of unknown etiology. By demonstrating that fatigue in PBC is associated with an impaired cognitive performance, previous studies have pointed out the possibility of brain abnormalities underlying fatigue in PBC. Whether structural brain changes are present in PBC patients with fatigue, however, is unclear. To evaluate the role of structural brain abnormalities in PBC patients severely affected from fatigue we, therefore, performed a case-control cerebral magnetic resonance imaging (cMRI) study and correlated changes of white and grey brain matter with the cognitive and attention performance. 20 female patients with PBC and 20 female age-matched controls were examined in this study. The assessment of fatigue, psychological symptoms, cognitive and attention performance included clinical questionnaires, established cognition tests and a computerized test battery of attention performance. T1-weighted cMRI and diffusion tensor imaging (DTI) scans were acquired with a 3 Tesla scanner. Structural brain alterations were investigated with voxel-based morphometry (VBM) and DTI analyses. Results were correlated to the cognitive and attention performance. Compared to healthy controls, PBC patients had significantly higher levels of fatigue and associated psychological symptoms. Except for an impairment of verbal fluency, no cognitive or attention deficits were found in the PBC cohort. The VBM and DTI analyses revealed neither major structural brain abnormalities in the PBC cohort nor correlations with the cognitive and attention performance. Despite the high burden of fatigue and selected cognitive deficits, the attention performance of PBC patients appears to be comparable to healthy people. As structural brain alterations do not seem to be present in PBC patients with fatigue, fatigue in PBC must be regarded as purely functional. Future studies should evaluate, whether functional brain changes underlie fatigue in PBC.
Terziroli Beretta-Piccoli, Benedetta; Guillod, Caroline; Marsteller, Igor; Blum, Roland; Mazzucchelli, Luca; Mondino, Chiara; Invernizzi, Pietro; Gershwin, M Eric; Mainetti, Carlo
2017-08-01
Primary biliary cholangitis (PBC) is a rare autoimmune cholestatic liver disease. It is often associated with extrahepatic autoimmune diseases. Skin disorders are sporadically reported in association with PBC. We report an unusual case of PBC associated with acquired reactive perforating dermatosis (ARPD) and present a review of the literature on skin disorders associated with PBC. Our patient presented to the dermatology department with generalized pruritus associated with nodular perforating skin lesions on the trunk, and cholestatic liver disease of unknown origin. After having established both diagnosis of ARPD and PBC, she was managed in an interdisciplinary manner, and both her skin and liver conditions improved gradually. Only one similar case is reported in the literature, in that case, the liver disease was not treated. By reviewing the literature, we found that lichen planus, vitiligo, and psoriasis are the most frequent skin disorders associated with PBC. However, there is only limited data about specific skin disorders associated with PBC. This case report of a patient with PBC associated with ARPD underlines the importance of interdisciplinary management of patients with rare liver diseases combined with rare skin disorders. The present review of the literature shows that probably, immune-mediated skin conditions are not more frequent in PBC patients than in the general population. However, the available data are scant; there is a need for high-quality data on skin conditions associated with PBC.
Primary biliary cirrhosis associated with Graves' disease in a male patient.
Suzuki, Yuji; Ishida, Kazuyuki; Takahashi, Hiroshi; Koeda, Norihiko; Kakisaka, Keisuke; Miyamoto, Yasuhiro; Suzuki, Akiko; Takikawa, Yasuhiro
2016-04-01
Primary biliary cirrhosis (PBC), which predominantly affects women, has been associated with various autoimmune diseases. Although hypothyroidism accompanying PBC is well documented, the concomitance of PBC and hyperthyroidism is rare. Herein, we report the case of a 62-year-old man who was diagnosed with PBC several years after the development of Graves' disease. This is the first case of a male patient developing PBC with Graves' disease. Both serum alanine aminotransferase levels and serum thyroid hormone levels were normalized after the administration of thiamazole for Graves' disease. However, the cholestatic liver enzyme abnormalities continued, indicating that the PBC was actualized by the administration of thiamazole. After starting ursodeoxycholic acid treatment, cholestatic liver enzyme abnormalities improved. Taken together, when a cholestatic pattern of liver enzymes is observed during follow-up for Graves' disease, an association between Graves' disease and PBC should be considered as a differential diagnosis.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Graham, John B.; Nassauer, Joan I.; Currie, William S.
Wild bee populations are currently under threat, which has led to recent efforts to increase pollinator habitat in North America. Simultaneously, U.S. federal energy policies are beginning to encourage perennial bioenergy cropping (PBC) systems, which have the potential to support native bees. Our objective was to explore the potentially interactive effects of crop composition, total PBC area, and PBC patches in different landscape configurations. Using a spatially-explicit modeling approach, the Lonsdorf model, we simulated the impacts of three perennial bioenergy crops (PBC: willow, switchgrass, and prairie), three scenarios with different total PBC area (11.7%, 23.5% and 28.8% of agricultural landmore » converted to PBC) and two types of landscape configurations (PBC in clustered landscape patterns that represent realistic future configurations or in dispersed neutral landscape models) on a nest abundance index in an Illinois landscape. Our modeling results suggest that crop composition and PBC area are particularly important for bee nest abundance, whereas landscape configuration is associated with bee nest abundance at the local scale but less so at the regional scale. Moreover, strategies to enhance wild bee habitat should therefore emphasize the crop composition and amount of PBC.« less
Graham, John B.; Nassauer, Joan I.; Currie, William S.; ...
2017-03-25
Wild bee populations are currently under threat, which has led to recent efforts to increase pollinator habitat in North America. Simultaneously, U.S. federal energy policies are beginning to encourage perennial bioenergy cropping (PBC) systems, which have the potential to support native bees. Our objective was to explore the potentially interactive effects of crop composition, total PBC area, and PBC patches in different landscape configurations. Using a spatially-explicit modeling approach, the Lonsdorf model, we simulated the impacts of three perennial bioenergy crops (PBC: willow, switchgrass, and prairie), three scenarios with different total PBC area (11.7%, 23.5% and 28.8% of agricultural landmore » converted to PBC) and two types of landscape configurations (PBC in clustered landscape patterns that represent realistic future configurations or in dispersed neutral landscape models) on a nest abundance index in an Illinois landscape. Our modeling results suggest that crop composition and PBC area are particularly important for bee nest abundance, whereas landscape configuration is associated with bee nest abundance at the local scale but less so at the regional scale. Moreover, strategies to enhance wild bee habitat should therefore emphasize the crop composition and amount of PBC.« less
Aiba, Yoshihiro; Harada, Kenichi; Komori, Atsumasa; Ito, Masahiro; Shimoda, Shinji; Nakamura, Hitomi; Nagaoka, Shinya; Abiru, Seigo; Migita, Kiyoshi; Ishibashi, Hiromi; Nakanuma, Yasuni; Nishida, Nao; Kawashima, Minae; Tokunaga, Katsushi; Yatsuhashi, Hiroshi; Nakamura, Minoru
2014-05-01
Through a genome-wide association study of a Japanese population, we recently identified TNFSF15, a gene encoding TNF-like ligand 1A (TL1A), as a susceptibility gene for primary biliary cirrhosis (PBC). We investigated the clinical significance of TL1A and one of its receptors, decoy receptor 3 (DcR3), in PBC. We analysed the systemic and local expression of TL1A and DcR3 in 110 PBC patients and 46 healthy controls using enzyme-linked immunosorbent assay, quantitative polymerase chain reaction and immunohistochemical staining. Serum TL1A levels were significantly increased in PBC patients at both early and late stages as compared with healthy controls, and its levels were significantly decreased in early-stage PBC patients after ursodeoxycholic acid (UDCA) treatment. TL1A was immunohistochemically localized to biliary epithelial cells, Kupffer cells, blood vessels and infiltrating mononuclear cells in the PBC liver. In addition, TL1A messenger RNA expression was increased in the PBC liver as compared with the non-diseased liver. Serum DcR3 levels were also significantly increased in PBC patients, and were significantly decreased after UDCA treatment in early-stage PBC patients. These results indicate that TL1A and DcR3 may play an important role in the pathogenesis of PBC. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Eosinophilia in primary biliary cirrhosis.
Yamazaki, K; Nakadate, I; Suzuki, K; Sato, S; Masuda, T
1996-03-01
Recent studies have shown the occurrence of eosinophilia in patients with primary biliary cirrhosis (PBC). To examine whether eosinophilia is indeed a distinctive feature of PBC, we performed extensive leukocyte differential analysis using a highly sophisticated hematology instrument. We also investigated the relationship between eosinophil dynamics and clinical features of PBC including the effects of ursodeoxycholic acid (UDCA) treatment. A flow cytometry-based blood cell analyzer (Technicon H6000) was used to examine peripheral blood eosinophil counts in 38 patients with PBC and 131 patients with various liver deseases. We also performed eosinophil quantitation in 19 PBC patients before and after administration of UDCA for 4 wk. Patients with PBC had significantly higher relative and absolute eosinophil counts when compared with other liver diseases (5.7 +/- 0.5% [p < 0.0001, mean +/- SEM] and 312 +/- 26 cells/microliter [p < 0.01], respectively). Twenty-one of 38 PBC patients (55%) exhibited relative eosinophilia. In patients with PBC, the eosinophil count was: 1) significantly higher in those with early histological stages (stage I-II, 6.5 +/- 0.5% vs stage III-IV, 4.4 +/- 0.7%,p < 0.05), 2) positively correlated with basophil count (p < 0.01), serum IgA levels (p < 0.05), and the degree of eosinophil infiltration in the portal tract (p < 0.01), and 3) markedly reduced by UDCA treatment (before: 5.9 +/- 0.7%, 307 +/- 37 cells/microliter; after: 2.8 +/- 0.03% [p < 0.001], 162 +/- 26 cells/microliter ¿p < 0.001]). Eosinophilia is a common and distinctive feature of patients with PBC. UDCA ameliorates eosinophilia as well as liver function tests in PBC patients. Eosinophilia may be useful as one of the initial clues in the diagnosis of PBC, especially in its early stage.
Identification of new autoantigens for primary biliary cirrhosis using human proteome microarrays.
Hu, Chao-Jun; Song, Guang; Huang, Wei; Liu, Guo-Zhen; Deng, Chui-Wen; Zeng, Hai-Pan; Wang, Li; Zhang, Feng-Chun; Zhang, Xuan; Jeong, Jun Seop; Blackshaw, Seth; Jiang, Li-Zhi; Zhu, Heng; Wu, Lin; Li, Yong-Zhe
2012-09-01
Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease of unknown etiology and is considered to be an autoimmune disease. Autoantibodies are important tools for accurate diagnosis of PBC. Here, we employed serum profiling analysis using a human proteome microarray composed of about 17,000 full-length unique proteins and identified 23 proteins that correlated with PBC. To validate these results, we fabricated a PBC-focused microarray with 21 of these newly identified candidates and nine additional known PBC antigens. By screening the PBC microarrays with additional cohorts of 191 PBC patients and 321 controls (43 autoimmune hepatitis, 55 hepatitis B virus, 31 hepatitis C virus, 48 rheumatoid arthritis, 45 systematic lupus erythematosus, 49 systemic sclerosis, and 50 healthy), six proteins were confirmed as novel PBC autoantigens with high sensitivities and specificities, including hexokinase-1 (isoforms I and II), Kelch-like protein 7, Kelch-like protein 12, zinc finger and BTB domain-containing protein 2, and eukaryotic translation initiation factor 2C, subunit 1. To facilitate clinical diagnosis, we developed ELISA for Kelch-like protein 12 and zinc finger and BTB domain-containing protein 2 and tested large cohorts (297 PBC and 637 control sera) to confirm the sensitivities and specificities observed in the microarray-based assays. In conclusion, our research showed that a strategy using high content protein microarray combined with a smaller but more focused protein microarray can effectively identify and validate novel PBC-specific autoantigens and has the capacity to be translated to clinical diagnosis by means of an ELISA-based method.
Marí-Alfonso, Begoña; Amengual-Guedan, María José; Vergara-Gómez, Mercè; Simeón-Aznar, Carmen Pilar; Fonollosa-Plà, Vicente; Jove-Buxeda, Esther; Oliva-Morera, Juan; Tolosa-Vilella, Carles
2016-01-01
Primary biliary cirrhosis (PBC) is associated to any systemic autoimmune disease (SAD), in particular systemic sclerosis (SSc). To investigate the prevalence of SAD in a cohort of patients with PBC, specifically the prevalence of SSc and its clinical subtypes, and determining the clinical and biological profile of patients with associated PBC and SSc. Observational study of 62 patients with PBC following a protocol that included an anamnesis and physical examination to detect the presence of SAD as well as a nailfold capillaroscopy and an immunological study with specific SSc autoantibodies. A comparative analysis was conducted between patients with isolated PBC and patients with PBC and an associated SAD. SAD was associated to PBC in 22 patients (35,4%), and SSc was the most frequent illness, identified in 13 cases (21%). Five patients (8%) without previous diagnosis of SAD fulfilled pre-scleroderma criteria, according to LeRoy and Medsger criteria. The presence of anticentromere antibodies (54,5% vs. 5%, P<.001) was the unique immunological determination identified more frequently in patients with PBC-SAD. The SSc suggestive capillary pattern was visualized in 11 patients (20,4%), mainly the slow pattern. No factors associated with greater morbi-mortality were identified in the PBC-SAD group. It does exist a subgroup of patients with PBC and clinical-biological features suggestive of an SAD, which advise a protocolized study to detect early the association to an SAD. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.
Tovoli, Francesco; Granito, Alessandro; Giampaolo, Luca; Frisoni, Magda; Volta, Umberto; Fusconi, Marco; Masi, Chiara; Lenzi, Marco
2014-03-01
Primary biliary cirrhosis (PBC) is frequently associated with other autoimmune diseases, including systemic sclerosis (SSc). In the last years many efforts have been dedicated to the research of widely accepted criteria for the early diagnosis of SSc. Since studies on the prevalence of early SSc in PBC patients are lacking, our aim was to investigate its hitherto unknown prevalence in a large cohort of PBC patients. We studied 80 PBC patients and 72 patients with other chronic liver diseases. Diagnostic workup included research into signs of connective tissue disease, determination of autoantibody profile, and examination of capillary abnormalities through nailfold videocapillaroscopy. Ten PBC patients (12.5%) satisfied diagnostic criteria for early SSc and 5 (6.3%) had definite SSc. None of the patients in the control group were diagnosed either with early or definite SSc. No differences were observed in terms of aminotransferases, alkaline phosphatase, and liver function tests between PBC patients with and without associated SSc. Early SSc is significantly frequent in PBC patients. The detection of early SSc in PBC patients may lead to a prompt treatment of its complications, preventing inabilities and preserving the chance of liver transplantation.
Wang, Zhenyu; Zong, Haiying; Zheng, Hao; Liu, Guocheng; Chen, Lei; Xing, Baoshan
2015-11-01
Adding biochar into soils has potential to manipulate soil nitrification process due to its impacts on nitrogen (N) cycling, however, the exact mechanisms underlying the alteration of nitrification process in soils are still not clear. Nitrification in an acidic orchard soil amended with peanut shell biochar (PBC) produced at 400 °C was investigated. Nitrification was weakened by PBC addition due to the decreased NH4(+)-N content and reduced ammonia-oxidizing bacteria (AOB) abundance in PBC-amended soils. Adding phenolic compounds (PHCs) free biochar (PBC-P) increased the AOB abundance and the DGGE band number, indicating that PHCs remaining in the PBC likely reduced AOB abundance and diversity. However, PBC addition stimulated rape growth and increased N bioavailability. Overall, adding PBC could suppress the nitrification process and improve N bioavailability in the agricultural soils, and thus possibly mitigate the environmental negative impacts and improving N use efficiency in the acidic soils added with N fertilizer. Copyright © 2015 Elsevier Ltd. All rights reserved.
Influence of different dose calculation algorithms on the estimate of NTCP for lung complications
Bäck, Anna
2013-01-01
Due to limitations and uncertainties in dose calculation algorithms, different algorithms can predict different dose distributions and dose‐volume histograms for the same treatment. This can be a problem when estimating the normal tissue complication probability (NTCP) for patient‐specific dose distributions. Published NTCP model parameters are often derived for a different dose calculation algorithm than the one used to calculate the actual dose distribution. The use of algorithm‐specific NTCP model parameters can prevent errors caused by differences in dose calculation algorithms. The objective of this work was to determine how to change the NTCP model parameters for lung complications derived for a simple correction‐based pencil beam dose calculation algorithm, in order to make them valid for three other common dose calculation algorithms. NTCP was calculated with the relative seriality (RS) and Lyman‐Kutcher‐Burman (LKB) models. The four dose calculation algorithms used were the pencil beam (PB) and collapsed cone (CC) algorithms employed by Oncentra, and the pencil beam convolution (PBC) and anisotropic analytical algorithm (AAA) employed by Eclipse. Original model parameters for lung complications were taken from four published studies on different grades of pneumonitis, and new algorithm‐specific NTCP model parameters were determined. The difference between original and new model parameters was presented in relation to the reported model parameter uncertainties. Three different types of treatments were considered in the study: tangential and locoregional breast cancer treatment and lung cancer treatment. Changing the algorithm without the derivation of new model parameters caused changes in the NTCP value of up to 10 percentage points for the cases studied. Furthermore, the error introduced could be of the same magnitude as the confidence intervals of the calculated NTCP values. The new NTCP model parameters were tabulated as the algorithm was varied from PB to PBC, AAA, or CC. Moving from the PB to the PBC algorithm did not require new model parameters; however, moving from PB to AAA or CC did require a change in the NTCP model parameters, with CC requiring the largest change. It was shown that the new model parameters for a given algorithm are different for the different treatment types. PACS numbers: 87.53.‐j, 87.53.Kn, 87.55.‐x, 87.55.dh, 87.55.kd PMID:24036865
Tanaka, Atsushi; Hirohara, Junko; Nakano, Toshiaki; Yagi, Minami; Namisaki, Tadashi; Yoshiji, Hitoshi; Nakanuma, Yasuni; Takikawa, Hajime
2018-02-06
As primary biliary cholangitis (PBC) is a heterogeneous disease, we hypothesized that there is a population of patients with early PBC who do not require prompt treatment with ursodeoxycholic acid (UDCA). In this study, we analyzed data from a large-scale PBC cohort in Japan, and retrospectively investigated whether outcomes of early PBC patients were affected with prompt or deferred/no UDCA treatment. We defined early PBC as asymptomatic, serum alkaline phosphatase <1.67-fold the upper limit of normal, normal bilirubin, and histological stages I-II at presentation. We compared the outcomes of early PBC patients between the treatment regimens; prompt treatment group (UDCA was initiated within 1 year after diagnosis) and deferred/no treatment group (UDCA initiated >1 year after diagnosis or never initiated). Furthermore, we examined the outcomes of early PBC patients alternatively defined only with symptomatology and biochemistry. We identified 562 early PBC patients (prompt: n = 509; deferred/no treatment: n = 53). Incidence rates (per 1000 patient-years) for liver-related mortality or liver transplantation and decompensating events were 0.5 and 5.4, respectively, in the prompt treatment group, and 0 and 8.7, respectively, in the deferred/no treatment group. Multivariate analyses showed that age and bilirubin were significantly associated with developing decompensating events, whereas the prompt and deferred/no treatments were not. We obtained similar results in early PBC patients defined without histological examination. We showed that deferred/no treatment for early PBC patients did not affect the outcomes. This study provides a rationale for a future prospective, randomized study. © 2018 The Japan Society of Hepatology.
The impact of depression and antidepressant usage on primary biliary cholangitis clinical outcomes
Kaplan, Gilaad G.; Almishri, Wagdi; Vallerand, Isabelle; Frolkis, Alexandra D.; Patten, Scott; Swain, Mark G.
2018-01-01
Background Depression is prevalent in primary biliary cholangitis (PBC) patients. Our aims were to examine the effects of depression and antidepressants on hepatic outcomes of PBC patients. Methods We used the UK Health Improvement Network database to identify PBC patients between 1974 and 2007. Our primary outcome was one of three clinical events: decompensated cirrhosis, liver transplantation and death. We assessed depression and each class of antidepressant medication in adjusted multivariate Cox proportional hazards models to identify independent predictors of outcomes. In a sensitivity analysis, the study population was restricted to PBC patients using ursodeoxycholic acid (UDCA). Results We identified 1,177 PBC patients during our study period. In our cohort, 86 patients (7.3%) had a depression diagnosis prior to PBC diagnosis, while 79 patients (6.7%) had a depression diagnosis after PBC diagnosis. Ten-year incidence of mortality, decompensated cirrhosis, and liver transplantation were 13.4%, 6.6%, and 2.0%, respectively. In our adjusted models, depression status was not a predictor of poor outcomes. After studying all classes of antidepressants, using the atypical antidepressant mirtazapine after PBC diagnosis was significantly protective (Adjusted HR 0.23: 95% CI 0.07–0.72) against poor liver outcomes (decompensation, liver transplant, mortality), which remained statistically significant in patients using UCDA (HR 0.21: 95% CI 0.05–0.83). Conclusions In our study, depression was not associated with poor clinical outcomes. However, using the antidepressant mirtazapine was associated with decreased mortality, decompensated cirrhosis and liver transplantation in PBC patients. These findings support further assessment of mirtazapine as a potential treatment for PBC patients. PMID:29617396
Hanson, Jessica D; Nothwehr, Faryle; Yang, Jingzhen Ginger; Romitti, Paul
2015-07-01
Unintended pregnancies can have negative consequences for both mother and child. The focus of this study was to utilize perceived behavioral control measures (PBC; part of the theory of planned behavior) to identify relevant behavioral determinants of birth control use. This study also tested associations between direct and indirect PBC measures and intention of birth control use and between intention and birth control use. The methods included a randomly selected sample of patients at a health care system in the Upper Midwest who were sent a self-administered survey, with 190 non-pregnant women returning completed surveys. Participants indicated a high level of control over using birth control, and a significant positive correlation was observed between direct and indirect PBC measures. Participants also reported high intentions to use birth control, and a significant positive correlation was observed between intention and PBC. Additionally, both PBC measures and intention were independently and significantly associated with behavior, and PBC remained significantly associated with behavior when intention was added into the model. In conclusion, compared to the previous literature, this study is unique in that it examines indirect PBC measures and also the important role that PBC plays with actual birth control behavior.
Nothwehr, Faryle; Yang, Jingzhen Ginger; Romitti, Paul
2018-01-01
Unintended pregnancies can have negative consequences for both mother and child. The focus of this study was to utilize perceived behavioral control measures (PBC; part of the theory of planned behavior) to identify relevant behavioral determinants of birth control use. This study also tested associations between direct and indirect PBC measures and intention of birth control use and between intention and birth control use. The methods included a randomly selected sample of patients at a health care system in the Upper Midwest who were sent a self-administered survey, with 190 non-pregnant women returning completed surveys. Participants indicated a high level of control over using birth control, and a significant positive correlation was observed between direct and indirect PBC measures. Participants also reported high intentions to use birth control, and a significant positive correlation was observed between intention and PBC. Additionally, both PBC measures and intention were independently and significantly associated with behavior, and PBC remained significantly associated with behavior when intention was added into the model. In conclusion, compared to the previous literature, this study is unique in that it examines indirect PBC measures and also the important role that PBC plays with actual birth control behavior. PMID:25421330
Guy, Jennifer E.; Qian, Peiqing; Lowell, Jeffrey A.; Peters, Marion G.
2014-01-01
Primary biliary cirrhosis (PBC) recurs after orthotopic liver transplantation (OLT) in up to one-third of patients. These patients are typically asymptomatic, can be identified by abnormal liver biochemistries, and have evidence of histologic recurrence on liver biopsy. The effect of treatment on recurrence has not been determined. This pilot study evaluates the factors associated with recurrent PBC and describes our experience using ursodeoxycholic acid treatment in this patient population. Forty-eight patients with PBC were followed for at least 1 yr post-OLT, and 27 patients (56%) developed abnormal serum alkaline phosphatase. Seventeen patients (35%) had evidence of recurrent PBC by liver biopsy. Patients with recurrent PBC had a trend toward longer warm ischemia times and more episodes of acute cellular rejection in the first year posttransplant, but this was not significant in multivariate analysis. Donor or recipient age, donor and recipient cytomegalovirus status, and dose of immunosuppression did not correlate with recurrence of PBC. Those patients diagnosed with recurrent PBC were placed on ursodeoxycholic acid, 15 mg/kg daily, with improvement in serum alkaline phosphatase in the majority. In conclusion, recurrent PBC is not infrequent post-OLT, and ursodeoxycholic acid can be used with some benefit post-OLT. Treatment effects on long-term survival are not known. PMID:16184542
Hudry, Bruno; Remacle, Sophie; Delfini, Marie-Claire; Rezsohazy, René; Graba, Yacine; Merabet, Samir
2012-01-01
Hox transcription factors control a number of developmental processes with the help of the PBC class proteins. In vitro analyses have established that the formation of Hox/PBC complexes relies on a short conserved Hox protein motif called the hexapeptide (HX). This paradigm is at the basis of the vast majority of experimental approaches dedicated to the study of Hox protein function. Here we questioned the unique and general use of the HX for PBC recruitment by using the Bimolecular Fluorescence Complementation (BiFC) assay. This method allows analyzing Hox-PBC interactions in vivo and at a genome-wide scale. We found that the HX is dispensable for PBC recruitment in the majority of investigated Drosophila and mouse Hox proteins. We showed that HX-independent interaction modes are uncovered by the presence of Meis class cofactors, a property which was also observed with Hox proteins of the cnidarian sea anemone Nematostella vectensis. Finally, we revealed that paralog-specific motifs convey major PBC-recruiting functions in Drosophila Hox proteins. Altogether, our results highlight that flexibility in Hox-PBC interactions is an ancestral and evolutionary conserved character, which has strong implications for the understanding of Hox protein functions during normal development and pathologic processes. PMID:22745600
Chronic inflammatory demyelinating polyneuropathy associated with primary biliary cirrhosis.
Murata, Ken-ya; Ishiguchi, Hiroshi; Ando, Ryuki; Miwa, Hideto; Kondo, Tomoyoshi
2013-12-01
We report a patient with chronic inflammatory demyelinating polyneuropathy associated with primary biliary cirrhosis (PBC). Except for minimal biochemical abnormalities, clinical symptoms of PBC were not observed, and we diagnosed our patient with asymptomatic PBC from the results of a liver biopsy. Although the patient noticed little muscle weakness, an electrophysiological study demonstrated slow conduction velocities and prolonged distal latencies, with definite conduction blocks in the median, ulnar, and tibial nerves. The disturbed sensory pattern was asymmetrical, and sensory nerve action potentials were not evoked. From these observations, we diagnosed this patient with chronic inflammatory demyelinating polyneuropathy. Neuropathy associated with PBC is very rare. We must differentiate demyelinating neuropathy with PBC in patients with asymmetrical sensory dominant neuropathy with high immunoglobulin M titers, and investigate for the presence of anti-mitochondrial antibodies to rule out a complication of asymptomatic PBC. Copyright © 2013 Elsevier Ltd. All rights reserved.
Aiba, Yoshihiro; Yamazaki, Keiko; Nishida, Nao; Kawashima, Minae; Hitomi, Yuki; Nakamura, Hitomi; Komori, Atsumasa; Fuyuno, Yuta; Takahashi, Atsushi; Kawaguchi, Takaaki; Takazoe, Masakazu; Suzuki, Yasuo; Motoya, Satoshi; Matsui, Toshiyuki; Esaki, Motohiro; Matsumoto, Takayuki; Kubo, Michiaki; Tokunaga, Katsushi; Nakamura, Minoru
2015-09-01
We previously identified TNFSF15 as the most significant susceptibility gene at non-HLA loci for both primary biliary cirrhosis (PBC) and Crohn's diseases (CD) in the Japanese population. The aim of this study is to identify further disease susceptibility genes shared by PBC and CD. We selected 15 and 33 genetic variants that were significantly associated with PBC and CD, respectively, based on previously reported genome-wide association studies of the Japanese population. Next, an association study was independently performed for these genetic variants in CD (1312 CD patients and 3331 healthy controls) and PBC (1279 PBC patients and 1015 healthy controls) cohorts. Two CD susceptibility genes, ICOSLG rs2838519 and IL12B rs6556412, were also nominally associated with susceptibility to PBC (P=3.85 × 10(-2) and P=8.40 × 10(-3), respectively). Three PBC susceptibility genes, CXCR5 rs6421571, STAT4 rs7574865 and NFKB1 rs230534, were nominally associated with susceptibility to CD (P=2.82 × 10(-2), P=3.88 × 10(-2) and P=2.04 × 10(-2), respectively). The effect of ICOSLG and CXCR5 variants were concordant but the effect of STAT4, NFKB1 and IL12B variants were discordant for PBC and CD. TNFSF15 and ICOSLG-CXCR5 might constitute a shared pathogenic pathway in the development of PBC and CD in the Japanese population, whereas IL12B-STAT4-NFKB1 might constitute an opposite pathogenic pathway, reflecting the different balance between Th1 and Th17 in the two diseases.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Park, J; Research Institute of Biomedical Engineering, The Catholic University of Korea, Seoul; Park, H
Purpose: Dosimetric effect and discrepancy according to the rectum definition methods and dose perturbation by air cavity in an endo-rectal balloon (ERB) were verified using rectal-wall (Rwall) dose maps considering systematic errors in dose optimization and calculation accuracy in intensity-modulated radiation treatment (IMRT) for prostate cancer patients. Methods: When the inflated ERB having average diameter of 4.5 cm and air volume of 100 cc is used for patient, Rwall doses were predicted by pencil-beam convolution (PBC), anisotropic analytic algorithm (AAA), and AcurosXB (AXB) with material assignment function. The errors of dose optimization and calculation by separating air cavity from themore » whole rectum (Rwhole) were verified with measured rectal doses. The Rwall doses affected by the dose perturbation of air cavity were evaluated using a featured rectal phantom allowing insert of rolled-up gafchromic films and glass rod detectors placed along the rectum perimeter. Inner and outer Rwall doses were verified with reconstructed predicted rectal wall dose maps. Dose errors and extent at dose levels were evaluated with estimated rectal toxicity. Results: While AXB showed insignificant difference of target dose coverage, Rwall doses underestimated by up to 20% in dose optimization for the Rwhole than Rwall at all dose range except for the maximum dose. As dose optimization for Rwall was applied, the Rwall doses presented dose error less than 3% between dose calculation algorithm except for overestimation of maximum rectal dose up to 5% in PBC. Dose optimization for Rwhole caused dose difference of Rwall especially at intermediate doses. Conclusion: Dose optimization for Rwall could be suggested for more accurate prediction of rectal wall dose prediction and dose perturbation effect by air cavity in IMRT for prostate cancer. This research was supported by the Leading Foreign Research Institute Recruitment Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (MSIP) (Grant No. 200900420)« less
Tang, Ruqi; Wei, Yiran; Li, Yanmei; Chen, Weihua; Chen, Haoyan; Wang, Qixia; Yang, Fan; Miao, Qi; Xiao, Xiao; Zhang, Haiyan; Lian, Min; Jiang, Xiang; Zhang, Jun; Cao, Qin; Fan, Zhuping; Wu, Maoying; Qiu, Dekai; Fang, Jing-Yuan; Ansari, Aftab; Gershwin, M Eric; Ma, Xiong
2018-03-01
A close relationship between gut microbiota and some chronic liver disorders has recently been described. Herein, we systematically performed a comparative analysis of the gut microbiome in primary biliary cholangitis (PBC) and healthy controls. We first conducted a cross-sectional study of 60 ursodeoxycholic acid (UDCA) treatment-naïve patients with PBC and 80 matched healthy controls. Second, an independent cohort composed of 19 treatment-naïve patients and 34 controls was used to validate the results. Finally, a prospective study was performed in a subgroup of 37 patients with PBC who underwent analysis before and after 6 months of UDCA treatment. Faecal samples were collected, and microbiomes were analysed by 16S ribosomal RNA gene sequencing. A significant reduction of within-individual microbial diversity was noted in PBC (p=0.03). A signature defined by decreased abundance of four genera and increased abundance of eight genera strongly correlated with PBC (area under curve=0.86, 0.84 in exploration and validation data, respectively). Notably, the abundance of six PBC-associated genera was reversed after 6 months of UDCA treatment. In particular, Faecalibacterium , enriched in controls, was further decreased in gp210-positive than gp210-negative patients (p=0.002). Of interest was the finding that the increased capacity for the inferred pathway, bacterial invasion of epithelial cells in PBC, highly correlated with the abundance of bacteria belonging to Enterobacteriaceae . This study presents a comprehensive landscape of gut microbiota in PBC. Dysbiosis was found in the gut microbiome in PBC and partially relieved by UDCA. Our study suggests that gut microbiota is a potential therapeutic target and diagnostic biomarker for PBC. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Feyereisen, Gary W; Christianson, Laura E; Moorman, Thomas B; Venterea, Rodney T; Coulter, Jeffrey A
2017-07-01
Nitrate-nitrogen (nitrate-N) removal rates can be increased substantially in denitrifying bioreactors with a corn ( L.) cob bed medium compared with woodchips; however, additional organic carbon (C) is released into the effluent. This laboratory column experiment was conducted to test the performance of a postbed chamber of inert plastic biofilm carrier (PBC) after corn cobs (CC) to extend the area of biofilm colonization, enhance nitrate-N removal, lower total organic C losses, and reduce nitrous oxide (NO) production at warm (15.5°C) and cold (1.5°C) temperatures. Treatments were CC only and CC plus PBC in series (CC-PBC). Across the two temperatures, nitrate-N load removal was 21% greater with CC-PBC than CC, with 54 and 44% of total nitrate N load, respectively. However, total organic C concentrations and loads were not significantly different between treatments. Colonization of the PBC by denitrifiers occurred, although gene abundance at the outlet (PBC) was less than at the inlet (CC). The PBC chamber increased nitrate-N removal rate and reduced cumulative NO production at 15.5°C, but not at 1.5°C. Across temperatures and treatments, NO production was 0.9% of nitrate-N removed. Including an additional chamber filled with PBC downstream from the CC bioreactor provided benefits in terms nitrate-N removal but did not achieve C removal. The presence of excess C, as well as available nitrate, in the PBC chamber suggests another unidentified limiting factor for nitrate removal. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
[Seropositivity for Chlamydia pneumoniae in patients with primary biliary cirrhosis].
Montaño-Loza, A; Vázquez-Ballesteros, E; Meza-Junco, J; Villalobos-Zapata, I; Olivera-Martínez, M
2006-03-01
Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease characterized by inflammatory injury and bile duct destruction. Recent studies suggest that Chlamydia pneumoniae could be associated with the development of PBC. The aim of this study was to determine the seroprevalence of C. pneumoniae in a cohort of patients with PBC. The presence of IgG antibodies against C. pneumoniae was investigated in 46 patients with PBC and in 105 subjects without cirrhosis. Twenty-one patients (46%) with PBC had antibodies against C. pneumoniae compared with 74 subjects (71%) in the control group (OR = 0.6; 95% CI, 0.3-1.2; p = NS). Subanalysis of the PBC group showed that patients with C. pneumoniae antibodies had a higher frequency of advanced Child-Pugh stages (24% A, 52% B and 24% C vs 64% A, 32% B and 4% C; p = 0.01), a higher score on the Mayo Clinic Prognostic Index (7.8 +/- 2.1 vs 5.6 +/- 1.2; p = 0.004), a higher frequency of ascites (29% vs 4%; OR = 9.6; 95% CI, 1-87; p = 0.02), higher total bilirubin levels (4.5 +/- 2.5 mg/dl vs 2.4 +/- 4.3 mg/dl, p = 0.001) and lower serum albumin levels (2.6 +/- 0.9 g/dl vs 3.3 +/- 0.6 g/dl, p = 0.02). No association was found between C. pneumoniae infection and PBC in this study. An association was found between the severity of PBC and C. pneumoniae, which may suggest a deleterious effect of C. pneumoniae infection or a predisposition in advanced stages of PBC to acquire infection with this microorganism.
Thyroid Dysfunction in Primary Biliary Cholangitis: A Comparative Study at Two European Centers.
Floreani, Annarosa; Mangini, Chiara; Reig, Anna; Franceschet, Irene; Cazzagon, Nora; Perini, Lisa; Caballería, Llorenç; Cocchio, Silvia; Baldo, Vincenzo; Parés, Albert
2017-01-01
Primary biliary cholangitis (PBC) is often associated with other autoimmune diseases, but little is known about the influence of thyroid disease (TD) on the natural history of PBC. Our aim is to analyze the association between PBC and TD, and the latter's impact on the natural history of PBC at two European centers. The study involved 921 PBC patients enrolled between 1975 and 2015 in Padova (376 patients) and Barcelona (545 patients), with a mean follow-up of 126.9±91.7 months. Data were recorded on patients' histological stage at diagnosis, biochemical data, associated extrahepatic autoimmune conditions, and clinical events, including hepatic decompensation. A total of 150 patients (16.3%) had TD, including 94 patients (10.2%) with Hashimoto's thyroiditis; 15 (1.6%) with Graves' disease; 22 (2.4%) with multinodular goiter; 7 (0.8%) with thyroid cancer; and 12 (1.3%) with other thyroid conditions. The prevalence of different types of TD was similar in Padova and Barcelona, except for Graves' disease and thyroid cancer, which were more frequent in the Padova cohort (15.7 vs. 5.0%, and 8.6 vs. 1.3%, respectively, P<0.05). Overall, there were no differences between PBC patients with and without TD in terms of their histological stage at diagnosis, hepatic decompensation events, occurrence of HCC, or liver transplantation rate. The presence of associated TD was not associated with lower survival for PBC patients in either cohort. TDs, and autoimmune TD like Hashimoto's thyroiditis in particular, are often associated with PBC, but the presence of TD does not influence the rate of hepatic complications or the natural history of PBC.
Quality of Life and Everyday Activities in Patients with Primary Biliary Cirrhosis
Selmi, Carlo; Gershwin, M. Eric; Lindor, Keith D.; Worman, Howard J.; Gold, Ellen B.; Watnik, Mitchell; Utts, Jessica; Invernizzi, Pietro; Kaplan, Marshall M.; Vierling, John M.; Bowlus, Christopher L.; Silveira, Marina G.; Bossi, Ilaria
2011-01-01
Primary biliary cirrhosis (PBC) is generally a slowly progressive disease that may lead to cirrhosis and liver failure. However, patients with PBC often suffer from a variety of symptoms long before the development of cirrhosis that include issues of daily living that have an impact on their work environment and their individual quality of life. We therefore examined multiple parameters by taking advantage of the database of our cohort of 1032 patients with PBC and 1041 matched controls. The data were obtained from patients from 23 tertiary referral centers throughout the United States and from rigorously matched controls by age, sex, ethnicity, and random-digit dialing. The data showed that patients with PBC were more likely than controls to have significant articular symptoms, a reduced ability to perform household chores, and the need for help with routine activities. Patients with PBC rated their overall activity similar or superior to that of controls; however, more of them reported limitations in their ability to carry out activities at work or at home and difficulties in everyday activities. PBC cases also more frequently reported limitations in participating in certain sports or exercises and pursuing various hobbies; however, they did not report significant limitations in social activities. In a multivariable analysis, household income, a diagnosis of systemic lupus erythematosus, limitations in work activities, a reduction in work secondary to disability, and church attendance were independently increased in PBC cases with respect to controls. Conclusion Our data indicate that the quality of life of patients with PBC in the United States is generally well preserved. Nevertheless, patients with PBC suffer significantly more than controls from a variety of symptoms that are beyond the immediate impact of liver failure and affect their lifestyle, personal relationships, and work activities. PMID:18027862
One session of partial-body cryotherapy (-110 °C) improves muscle damage recovery.
Ferreira-Junior, J B; Bottaro, M; Vieira, A; Siqueira, A F; Vieira, C A; Durigan, J L Q; Cadore, E L; Coelho, L G M; Simões, H G; Bemben, M G
2015-10-01
To evaluate the effects of a single session of partial-body cryotherapy (PBC) on muscle recovery, 26 young men performed a muscle-damaging protocol that consisted of five sets of 20 drop jumps with 2-min rest intervals between sets. After the exercise, the PBC group (n = 13) was exposed to 3 min of PBC at -110 °C, and the control group (n = 13) was exposed to 3 min at 21 °C. Anterior thigh muscle thickness, isometric peak torque, and muscle soreness of knee extensors were measured pre, post, 24, 48, 72, and 96 h following exercise. Peak torque did not return to baseline in control group (P < 0.05), whereas the PBC group recovered peak torques 96 h post exercise (P > 0.05). Peak torque was also higher after PBC at 72 and 96 h compared with control group (P < 0.05). Muscle thickness increased after 24 h in the control group (P < 0.05) and was significantly higher compared with the PBC group at 24 and 96 h (P < 0.05). Muscle soreness returned to baseline for the PBC group at 72 h compared with 96 h for controls. These results indicate that PBC after strenuous exercise may enhance recovery from muscle damage. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Brucker, Debra L.; Stewart, Maureen
2013-01-01
To explore whether the implementation of performance-based contracting (PBC) within the State of Maine’s substance abuse treatment system resulted in improved performance, one descriptive and two empirical analyses were conducted. The first analysis examined utilization and payment structure. The second study was designed to examine whether timeliness of access to outpatient (OP) and intensive outpatient (IOP) substance abuse assessments and treatment, measures that only became available after the implementation of PBC, differed between PBC and non-PBC agencies in the year following implementation of PBC. Using treatment admission records from the state treatment data system (N=9,128), logistic regression models run using generalized equation estimation techniques found no significant difference between PBC agencies and other agencies on timeliness of access to assessments or treatment, for both OP and IOP services. The third analysis, conducted using discharge data from the years prior to and after the implementation of performance-based contracting (N=6,740) for those agencies that became a part of the performance-based contracting system, was designed to assess differences in level of participation, retention, and completion of treatment. Regression models suggest that performance on OP client engagement and retention measures was significantly poorer the year after the implementation of PBC, but that temporal rather than a PBC effects were more significant. No differences were found between years for IOP level of participation or completion of treatment measures. PMID:21249461
Toward precision medicine in primary biliary cholangitis.
Carbone, Marco; Ronca, Vincenzo; Bruno, Savino; Invernizzi, Pietro; Mells, George F
2016-08-01
Primary biliary cholangitis is a chronic, cholestatic liver disease characterized by a heterogeneous presentation, symptomatology, disease progression and response to therapy. In contrast, clinical management and treatment of PBC is homogeneous with a 'one size fits all' approach. The evolving research landscape, with the emergence of the -omics field and the availability of large patient cohorts are creating a unique opportunity of translational epidemiology. Furthermore, several novel disease and symptom-modifying agents for PBC are currently in development. The time is therefore ripe for precision medicine in PBC. In this manuscript we describe the concept of precision medicine; review current approaches to risk-stratification in PBC, and speculate how precision medicine in PBC might develop in the near future. Copyright © 2016 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.
Ssengooba, Freddie; McPake, Barbara; Palmer, Natasha
2012-07-01
Performance-based contracting (PBC) is a tool that links rewards to attainment of measurable performance targets. Significant problems remain in the methods used to evaluate this tool. The primary focus of evaluations on the effects of PBC (black-box) and less attention to how these effects arise (open-box) generates suboptimal policy learning. A black-box impact evaluation of PBC pilot by the Development Research Group of the World Bank (DRG) and the Ministry of Health (MOH) concluded that PBC was ineffective. This paper reports a theory-based case study intended to clarify how and why PBC failed to achieve its objectives. To explain the observed PBC implementation and responses of participants, this case study employed two related theories i.e. complex adaptive system and expectancy theory respectively. A prospective study trailed the implementation of PBC (2003-2006) while collecting experiences of participants at district and hospital levels. Significant problems were encountered in the implementation of PBC that reflected its inadequate design. As problems were encountered, hasty adaptations resulted in a de facto intervention distinct from the one implied at the design stage. For example, inadequate time was allowed for the selection of service targets by the health centres yet they got 'locked-in' to these poor choices. The learning curve and workload among performance auditors weakened the validity of audit results. Above all, financial shortfalls led to delays, short-cuts and uncertainty about the size and payment of bonuses. The lesson for those intending to implement similar interventions is that PBC should not be attempted 'on the cheap'. It requires a plan to boost local institutional and technical capacities of implementers. It also requires careful consideration of the responses of multiple actors - both insiders and outsiders to the intended change process. Given the costs and complexity of PBC implementation, strengthening conventional approaches that are better attuned to low income contexts (financing resource inputs and systems management) remains a viable policy option towards improving health service delivery. Copyright © 2012 Elsevier Ltd. All rights reserved.
[Clinical and histopathological features of myositis associated with anti-mitochondrial antibodies].
Shimizu, Jun
2013-01-01
Anti-mitochondrial antibodies (AMA) are known to be characteristic markers of primary biliary cirrhosis (PBC). The association of PBC with myositis has been reported mainly as case reports, and comprehensive studies of the clinical and histopathological features of patients with myositis and AMAs or PBC have not been conducted thus far. We retrospectively reviewed 212 patients with inflammatory myopathies in our laboratory and found 24 patients with AMA-positive myositis (11%) (seven patients with PBC and 17 patients without PBC). The analysis of clinical and histopathological features revealed that myositis associated with AMAs frequently include patients with a clinically chronic disease course, muscle atrophy, cardiopulmonary involvement and granulomatous inflammation, regardless of the presence or absence of PBC. We also reviewed and analyzed the clinical features of previously reported patients. The analysis of 75 patients, which have been described in previous case reports including the ones of meeting abstracts, also showed the similar results about clinical features of myositis associated with AMAs and supported our findings. Our study suggests that myositis associated with AMAs form a characteristic subgroup.
Yamaguchi, Shintaro; Maruyama, Tatsuya; Wakino, Shu; Tokuyama, Hirobumi; Hashiguchi, Akinori; Tada, Shinichiro; Homma, Koichiro; Monkawa, Toshiaki; Thomas, James; Miyashita, Kazutoshi; Kurihara, Isao; Yoshida, Tadashi; Konishi, Konosuke; Hayashi, Koichi; Hayashi, Matsuhiko; Itoh, Hiroshi
2015-11-11
Primary biliary cirrhosis (PBC) is an immune-mediated chronic cholestatic liver disease, characterized by increased concentrations of serum IgM and the presence of circulating anti-mitochondrial antibodies. Although bone diseases such as osteoporosis or osteodystrophy are commonly associated with PBC, osteomalacia which is caused by abnormal vitamin D metabolism, mineralization defects, and phosphate deficiency has not been recognized as a complication of PBC. We report the case of a 49-year-old Japanese woman who complained of multiple fractures. Hypophosphatemic osteomalacia was diagnosed from a low serum phosphorus level, 1,25-dihydroxyvitamin D3 level, high levels of bone specific alkaline phosphatase and the findings of bone scintigraphy, although a bone biopsy was not performed. Twenty four hour urine demonstrated a low renal fractional tubular reabsorption of phosphate, increased fractional excretion of uric acid and generalized aminoaciduria. An intravenous bicarbonate loading test suggested the presence of proximal renal tubular acidosis (RTA). These biochemical data indicated Fanconi syndrome with proximal RTA. A kidney biopsy demonstrated the features of tubulointerstitial nephritis (TIN). The patient was also suspected as having primary biliary cirrhosis (PBC) because of high levels of alkaline phosphatase, IgM and the presence of anti-mitochondrial M2 antibody, though biochemical liver function was normal. Sequential liver biopsy was compatible with PBC and the diagnosis of PBC was definite. After administration of 1,25 dihydroxyvitamin D3, neutral potassium phosphate, sodium bicarbonate for osteomalacia and subsequent predonizolone for TIN, symptoms of fractures were relieved and renal function including Fanconi syndrome was ameliorated. In this case, asymptomatic PBC was shown to induce TIN with Fanconi syndrome with dysregulation of electrolytes and vitamin D metabolism, which in turn led to osteomalacia with multiple fractures. Osteomalacia has not been recognized as a result of the renal involvement of PBC. PBC and its rare complication of TIN with Fanconi syndrome should be considered in adult patients with unexplained osteomalacia even in the absence of liver dysfunction.
Tanaka, Atsushi; Ma, Xiong; Yokosuka, Osamu; Weltman, Martin; You, Hong; Amarapurkar, Deepak N; Kim, Yoon Jun; Abbas, Zaigham; Payawal, Diana A; Chang, Ming-Ling; Efe, Cumali; Ozaslan, Ersan; Abe, Masanori; Mitchell-Thain, Robert; Zeniya, Mikio; Han, Kwang Hyub; Vierling, John M; Takikawa, Hajime
2016-11-01
During the 25th annual meeting of the Asia-Pacific Association for the Study of the Liver (APASL 2016) in Tokyo, we organized and moderated an inaugural satellite symposium on the autoimmune liver diseases, autoimmune hepatitis (AIH) and primary biliary cholangitis (PBC). Following the keynote lecture by John M. Vierling (USA), speakers from the Asia-Pacific region provided an up-to-date perspective on the epidemiology, clinical practice and research in AIH and PBC in the Asia-Pacific region. Although epidemiology and clinical features of AIH seem to be similar in East Asia compared to those in western countries, the majority of patients with AIH are detected at an advanced stage and have higher mortality rates in South Asia, indicating an unmet need for earlier diagnosis and the initiation of appropriate immunosuppressive treatment. PBC is more commonly seen in Australia and East Asia. As of 2016, clinical practice guidelines (CPG) for PBC have been published in Japan and China. Ursodeoxycholic acid (UDCA) is recommended as a first-line therapy by both CPG. Nevertheless, one of the unmet therapeutic needs in PBC is the treatment of patients refractory to or intolerant of UDCA. It is of interest that the prevalence of chronic hepatitis B (CHB) in PBC patients was low in Taiwan and mainland China where the prevalence of CHB is very high. In this review, we overview this exciting and epoch-making symposium.
Samur, Sumeyye; Klebanoff, Matthew; Banken, Reiner; Pratt, Daniel S; Chapman, Rick; Ollendorf, Daniel A; Loos, Anne M; Corey, Kathleen; Hur, Chin; Chhatwal, Jagpreet
2017-03-01
Primary biliary cholangitis (PBC) is a chronic, progressive autoimmune liver disease that mainly affects middle-aged women. Obeticholic acid (OCA), which was recently approved by the Food and Drug Administration for PBC treatment, has demonstrated positive effects on biochemical markers of liver function. Our objective was to evaluate the long-term clinical impact and cost-effectiveness of OCA as a second-line treatment for PBC in combination with ursodeoxycholic acid (UDCA) in adults with an inadequate response to UDCA. We developed a mathematical model to simulate the lifetime course of PBC patients treated with OCA+UDCA versus UDCA alone. Efficacy data were derived from the phase 3 PBC OCA International Study of Efficacy trial, and the natural history of PBC was informed by published clinical studies. Model outcomes were validated using the PBC Global Study. We found that in comparison with UDCA, OCA+UDCA could decrease the 15-year cumulative incidences of decompensated cirrhosis from 12.2% to 4.5%, hepatocellular carcinoma from 9.1% to 4.0%, liver transplants from 4.5% to 1.2%, and liver-related deaths from 16.2% to 5.7% and increase 15-year transplant-free survival from 61.1% to 72.9%. The lifetime cost of PBC treatment would increase from $63,000 to $902,000 (1,330% increment). The discounted quality-adjusted life years with UDCA and OCA+UDCA were 10.74 and 11.78, respectively, and the corresponding costs were $142,300 and $633,900, resulting in an incremental cost-effectiveness ratio of $473,400/quality-adjusted life year gained. The results were most sensitive to the cost of OCA. OCA is a promising new therapy to substantially improve the long-term outcomes of PBC patients, but at its current annual price of $69,350, it is not cost-effective using a willingness-to-pay threshold of $100,000/quality-adjusted life year; pricing below $18,450/year is needed to make OCA cost-effective. (Hepatology 2017;65:920-928). © 2016 by the American Association for the Study of Liver Diseases.
Hausswirth, Christophe; Schaal, Karine; Le Meur, Yann; Bieuzen, François; Filliard, Jean-Robert; Volondat, Marielle; Louis, Julien
2013-01-01
The aim of this study was to compare the effects of a single whole-body cryostimulation (WBC) and a partial-body cryostimulation (PBC) (i.e., not exposing the head to cold) on indices of parasympathetic activity and blood catecholamines. Two groups of 15 participants were assigned either to a 3-min WBC or PBC session, while 10 participants constituted a control group (CON) not receiving any cryostimulation. Changes in thermal, physiological and subjective variables were recorded before and during the 20-min after each cryostimulation. According to a qualitative statistical analysis, an almost certain decrease in skin temperature was reported for all body regions immediately after the WBC (mean decrease±90% CL, -13.7±0.7°C) and PBC (-8.3±0.3°C), which persisted up to 20-min after the session. The tympanic temperature almost certainly decreased only after the WBC session (-0.32±0.04°C). Systolic and diastolic blood pressures were very likely increased after the WBC session, whereas these changes were trivial in the other groups. In addition, heart rate almost certainly decreased after PBC (-10.9%) and WBC (-15.2%) sessions, in a likely greater proportion for WBC compared to PBC. Resting vagal-related heart rate variability indices (the root-mean square difference of successive normal R-R intervals, RMSSD, and high frequency band, HF) were very likely increased after PBC (RMSSD: +54.4%, HF: +138%) and WBC (RMSSD: +85.2%, HF: +632%) sessions without any marked difference between groups. Plasma norepinephrine concentrations were likely to very likely increased after PBC (+57.4%) and WBC (+76.2%), respectively. Finally, cold and comfort sensations were almost certainly altered after WBC and PBC, sensation of discomfort being likely more pronounced after WBC than PBC. Both acute cryostimulation techniques effectively stimulated the autonomic nervous system (ANS), with a predominance of parasympathetic tone activation. The results of this study also suggest that a whole-body cold exposure induced a larger stimulation of the ANS compared to partial-body cold exposure. PMID:23991134
Linking human beta retrovirus infection with primary biliary cirrhosis.
Mason, A L; Zhang, G
2010-01-01
Several environmental agents have been linked with primary biliary cirrhosis (PBC) that include bacteria, xenobiotics and viruses. A human beta retrovirus (HBRV) related to mouse mammary tumor virus has been cloned and characterized from patients with PBC. This agent can be detected in the majority of patients' perihepatic lymph nodes by immunochemistry and RT-PCR. The HBRV has recently been isolated in culture and integration sites have been identified in the genome of patients to provide convincing evidence of beta retrovirus infection in patients. Three lines of evidence support a role for the virus in PBC. First, the beta retrovirus is linked with aberrant expression of mitochondrial protein(s) on the biliary epithelium cell (BEC) surface, a disease specific phenotype. Second, the related agent, mouse mammary tumor virus has been linked with autoimmune biliary disease in the NOD.c3c4 mouse model for PBC. In this mouse model, the virus is localized to diseased biliary epithelium that also display aberrant expression of the mitochondrial autoantigens. In translational studies, both patients with PBC and NOD.c3c4 mice demonstrate significant improvement in biliary disease with combination antiviral therapy. An overview of the biological relevance of the beta retrovirus infection in PBC will be discussed in this review. Copyright 2010 Elsevier Masson SAS. All rights reserved.
Mattner, Jochen
2016-01-01
Primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) represent the major clinical entities of chronic cholestatic liver diseases. Both disorders are characterized by portal inflammation and slowly progress to obliterative fibrosis and eventually liver cirrhosis. Although immune-pathogenic mechanisms have been implicated in the pathogenesis of PBC and PSC, neither disorder is considered to be a classical autoimmune disease, as PSC and PBC patients do not respond to immune-suppressants. Furthermore, the decreased bile flow resulting from the immune-mediated tissue assault and the subsequent accumulation of toxic bile products in PBC and PSC not only perpetuates biliary epithelial damage, but also alters the composition of the intestinal and biliary microbiota and its mutual interactions with the host. Consistent with the close association of PSC and inflammatory bowel disease (IBD), the polyclonal hyper IgM response in PBC and (auto-)antibodies which cross-react to microbial antigens in both diseases, an expansion of individual microbes leads to shifts in the composition of the intestinal or biliary microbiota and a subsequent altered integrity of epithelial layers, promoting microbial translocation. These changes have been implicated in the pathogenesis of both devastating disorders. Thus, we will discuss here these recent findings in the context of novel and alternative therapeutic options. PMID:27834858
Pareja, Fresia; Murray, Melissa P; Jean, Ryan Des; Konno, Fumiko; Friedlander, Maria; Lin, Oscar; Edelweiss, Marcia
2017-01-01
Discordance in the receptor status between primary breast carcinomas (PBC) and corresponding metastasis is well documented. Interrogation of the receptor status of metastatic breast carcinoma (MBC) in cytology material is common practice; however, its utility has not been thoroughly validated. We studied patients with MBC, and evaluated the concordance rates of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) between PBC surgical specimens and corresponding MBC cell blocks (CBs). We correlated the findings with clinicopathologic variables and with the fixation methods used. We searched for patients with MBC diagnosed on cytology from 2007 to 2009 and selected those with ER, PR and HER2 tested in both the PBC surgical specimens and the MBC CBs. We included CBs fixed in formalin and methanol based solution (CytoLyt®). All slides were reevaluated by cytopathologists. Clinical information was retrieved from the medical records. We studied 65 patients with PBC and MBC paired specimens. The concordance rates between PBC and MBC were 78.5%, 58.5% and 96.9%, for ER, PR and HER2, respectively. When discordant, PR status switched from positive (PBC) to negative (MBC) in most cases (23/27). The PR concordance rate was 45.2% for CBs fixed in formalin and 70.6% for those fixed with CytoLyt® (p=0.047). The ER, PR and HER2 concordance rates between the PBC and MBC CBs are similar to those reported in paired surgical specimens. PR status was the most prevalent discordance and was not accompanied by a switch in ER.
Sasaki, Motoko; Miyakoshi, Masami; Sato, Yasunori; Nakanuma, Yasuni
2012-03-01
Given autophagy is involved in the pathogenesis in primary biliary cirrhosis (PBC), we examined an involvement of p62 sequestosome-1 (p62), a specific cargo for autophagy, in the process of autophagy and cellular senescence in PBC. We examined immunohistochemically the expression of p62 in livers taken from patients with PBC (n = 46) and control livers (n = 78) and its colocalization with microtubule-associated proteins-light chain 3β (LC3), lysosome-associated membrane protein-1 (LAMP-1) and senescent markers (p16(INK) (4a) and p21(WAF) (1/Cip1) ). We examined the expression of p62 and LC3 in cultured biliary epithelial cells (BECs) treated with various stress. The effect of p62 knockdown with siRNA on stress-induced autophagy and cellular senescence was also assessed. The expression of p62 was specifically seen in cytoplasmic aggregates in BECs in the inflamed and damaged small bile ducts (SBDs) in PBC, when compared with non-inflamed ones in PBC and in control livers (P < 0.01). The co-expression of p62 with LC3, LAMP-1 and senescent markers was seen in the inflamed SBDs in PBC, but the intracytoplasmic localization was different. The expression of p62 and LC3 was significantly upregulated in BECs treated with various stress (P < 0.01) and pretreatment with bafilomycin A1 enhanced the accumulation of p62-positive aggregates in BECs with serum deprivation. The knockdown of p62 decreased stress-induced autophagy and cellular senescence. The aggregation of p62 is specifically increased in the damage bile ducts in PBC and may reflect dysfunctional autophagy, followed by cellular senescence in the pathogenesis of bile duct lesions in PBC. © 2011 John Wiley & Sons A/S.
Yagi, Minami; Tanaka, Atsushi; Namisaki, Tadashi; Takahashi, Atsushi; Abe, Masanori; Honda, Akira; Matsuzaki, Yasushi; Ohira, Hiromasa; Yoshiji, Hitoshi; Takikawa, Hajime
2018-04-16
Patients with primary biliary cholangitis (PBC) frequently suffer from pruritus, which can severely impair their health-related quality of life (HRQOL). Nalfurafine hydrochloride, a selective κ-opioid receptor agonist, was recently approved in Japan for refractory pruritus in patients with chronic liver diseases, but it still remains unclear whether this treatment improves the patient-reported outcome (PRO) in PBC patients with refractory pruritus. Herein, we conducted a multicenter, post-marketing, single-arm prospective study to investigate the efficacy of nalfurafine in terms of PRO, and the associations of the efficacy with any clinical characteristics. After screening for pruritus in 496 patients with PBC using PBC-40 and the visual analog scale (VAS), we identified 141 patients with moderate to severe pruritus; these were invited to participate in the study. The participants received 2.5 μg nalfurafine once daily for 12 weeks, and pruritus and HRQOL were assessed in week 12 of this treatment. Generic HRQOL, short form 36, blood chemistries, and serum autotaxin levels were also measured at baseline and at week 12. Forty-four patients participated in this study. The mean PBC-40 itch domain scores and VAS declined during the study period, from 8.56 to 7.63 (P = 0.041) and from 42.9 to 29.3 (P = 0.001) at baseline and at week 12, respectively, indicating a significant effect of nalfurafine. The other domains of PBC-40 and all domains of SF-36 were not significantly altered by this treatment. We failed to find any association between the change in VAS and PBC-40 itch scores and any clinical variable. Serum autotaxin levels were significantly increased during the study period. This study demonstrated that nalfurafine improved pruritus in patients with PBC, independent of their clinical characteristics, but had a limited effect on the PRO.
Jopson, Laura; Newton, Julia L; Palmer, Jeremy; Floudas, Achilleas; Isaacs, John; Qian, Jessica; Wilkinson, Jennifer; Trenell, Mike; Blamire, Andrew; Howel, Denise; Jones, David E
2015-01-01
Introduction Primary biliary cirrhosis (PBC) is an autoimmune liver disease with approximately 50% of patients experiencing fatigue. This can be a particularly debilitating symptom, affecting quality of life and resulting in social isolation. Fatigue is highlighted by patients as a priority for research and patient support groups were involved in designing this trial. This is the first randomised controlled trial to investigate a treatment for fatigue in PBC. The trial protocol is innovative as it utilises novel magnetic resonance spectroscopy (MRS) techniques as an outcome measure. The protocol will be valuable to research groups planning clinical trials targeting fatigue in PBC and also transferrable to other conditions associated with fatigue. Methods and analysis RITPBC is a Medical Research Council (MRC) and National Institute for Health Research (NIHR) Efficacy and Mechanism Evaluation Programme (EME)-funded project. It is a phase II, single-centre, randomised controlled, double-blinded trial comparing rituximab with placebo in fatigued PBC patients. 78 patients with PBC and moderate to severe fatigue will be randomised to receive two infusions of rituximab or placebo. The study aims to assess whether rituximab improves fatigue in patients with PBC, the safety, and tolerability of rituximab in PBC and the sustainability of any beneficial actions. The primary outcome will be an improvement in fatigue domain score of the PBC-40, a disease-specific quality of life measure, evaluated at 12-week assessment. Secondary outcome measures include novel MRS techniques assessing muscle bioenergetic function, physical activity, anaerobic threshold and symptom, and quality of life measures. The trial started recruiting in October 2012 and recruitment is ongoing. Ethics and dissemination The trial has ethical approval from the NRES Committee North East, has Clinical Trial Authorisation from MHRA and local R&D approval. Trial results will be communicated to participants, presented at national and international meetings and published in peer-reviewed journals. Trial registration number ISRCTN03978701. PMID:26297361
Wu, Q; Zhao, X; You, H
2017-05-18
This study aimed to test the diagnostic performance of a fully quantitative fibrosis assessment tool for liver fibrosis in patients with chronic hepatitis B (CHB), primary biliary cirrhosis (PBC) and non-alcoholic steatohepatitis (NASH). A total of 117 patients with liver fibrosis were included in this study, including 50 patients with CHB, 49 patients with PBC and 18 patients with NASH. All patients underwent liver biopsy (LB). Fibrosis stages were assessed by two experienced pathologists. Histopathological images of LB slices were processed by second harmonic generation (SHG)/two-photon excited fluorescence (TPEF) microscopy without staining, a system called qFibrosis (quantitative fibrosis) system. Altogether 101 quantitative features of the SHG/TPEF images were acquired. The parameters of aggregated collagen in portal, septal and fibrillar areas increased significantly with stages of liver fibrosis in PBC and CHB (P<0.05), but the same was not found for parameters of distributed collagen (P>0.05). There was a significant correlation between parameters of aggregated collagen in portal, septal and fibrillar areas and stages of liver fibrosis from CHB and PBC (P<0.05), but no correlation was found between the distributed collagen parameters and the stages of liver fibrosis from those patients (P>0.05). There was no significant correlation between NASH parameters and stages of fibrosis (P>0.05). For CHB and PBC patients, the highest correlation was between septal parameters and fibrosis stages, the second highest was between portal parameters and fibrosis stages and the lowest correlation was between fibrillar parameters and fibrosis stages. The correlation between the septal parameters of the PBC and stages is significantly higher than the parameters of the other two areas (P<0.05). The qFibrosis candidate parameters based on CHB were also applicable for quantitative analysis of liver fibrosis in PBC patients. Different parameters should be selected for liver fibrosis assessment in different stages of PBC compared with CHB.
Wu, Q.; Zhao, X.; You, H.
2017-01-01
This study aimed to test the diagnostic performance of a fully quantitative fibrosis assessment tool for liver fibrosis in patients with chronic hepatitis B (CHB), primary biliary cirrhosis (PBC) and non-alcoholic steatohepatitis (NASH). A total of 117 patients with liver fibrosis were included in this study, including 50 patients with CHB, 49 patients with PBC and 18 patients with NASH. All patients underwent liver biopsy (LB). Fibrosis stages were assessed by two experienced pathologists. Histopathological images of LB slices were processed by second harmonic generation (SHG)/two-photon excited fluorescence (TPEF) microscopy without staining, a system called qFibrosis (quantitative fibrosis) system. Altogether 101 quantitative features of the SHG/TPEF images were acquired. The parameters of aggregated collagen in portal, septal and fibrillar areas increased significantly with stages of liver fibrosis in PBC and CHB (P<0.05), but the same was not found for parameters of distributed collagen (P>0.05). There was a significant correlation between parameters of aggregated collagen in portal, septal and fibrillar areas and stages of liver fibrosis from CHB and PBC (P<0.05), but no correlation was found between the distributed collagen parameters and the stages of liver fibrosis from those patients (P>0.05). There was no significant correlation between NASH parameters and stages of fibrosis (P>0.05). For CHB and PBC patients, the highest correlation was between septal parameters and fibrosis stages, the second highest was between portal parameters and fibrosis stages and the lowest correlation was between fibrillar parameters and fibrosis stages. The correlation between the septal parameters of the PBC and stages is significantly higher than the parameters of the other two areas (P<0.05). The qFibrosis candidate parameters based on CHB were also applicable for quantitative analysis of liver fibrosis in PBC patients. Different parameters should be selected for liver fibrosis assessment in different stages of PBC compared with CHB. PMID:28538834
The Theory of Planned Behaviour and dietary patterns: A systematic review and meta-analysis.
McDermott, M S; Oliver, M; Simnadis, T; Beck, E J; Coltman, T; Iverson, D; Caputi, P; Sharma, R
2015-12-01
Promoting adherence to healthy dietary patterns is a critical public health issue. Models of behaviour, such as the Theory of Planned Behaviour (TPB) allow programme designers to identify antecedents of dietary patterns and design effective interventions. The primary aim of this study was to examine the association between TPB variables and dietary patterns. A systematic literature search was conducted to identify relevant studies. Random-effects meta-analysis was used to calculate average correlations. Meta-regression was used to test the impact of moderator variables. In total, 22 reports met the inclusion criteria. Attitudes had the strongest association with intention (r+=0.61) followed by perceived behavioural control (PBC, r+=0.46) and subjective norm (r+=0.35). The association between intention and behaviour was r+=0.47, and between PBC and behaviour r+=0.32. Moderator analyses revealed that younger participants had stronger PBC-behaviour associations than older participants had, and studies recording participants' perceptions of behaviour reported significantly higher intention-behaviour associations than did those using less subjective measures. TPB variables were found to have medium to large associations with both intention and behaviour that were robust to the influence of key moderators. Recommendations for future research include further examination of the moderation of TPB variables by age and gender and the use of more valid measures of eating behaviour. Copyright © 2015 Elsevier Inc. All rights reserved.
Wipe-rinse technique for quantitating microbial contamination on large surfaces.
Kirschner, L E; Puleo, J R
1979-01-01
The evaluation of an improved wipe-rinse technique for the bioassay of large areas was undertaken due to inherent inadequacies in the cotton swab-rinse technique to which assay of spacecraft is currently restricted. Four types of contamination control cloths were initially tested. A polyester-bonded cloth (PBC) was selected for further evaluation because of its superior efficiency and handling characteristics. Results from comparative tests with PBC and cotton swabs on simulated spacecraft surfaces indicated a significantly higher recovery efficiency for the PBC than for the cotton (90.4 versus 75.2%). Of the sampling areas sites studied, PBC was found to be most effective on surface areas not exceeding 0.74 m2 (8.0 feet 2). PMID:394682
Wipe-rinse technique for quantitating microbial contamination on large surfaces
NASA Technical Reports Server (NTRS)
Kirschner, L. E.; Puleo, J. R.
1979-01-01
The evaluation of an improved wipe-rinse technique for the bioassay of large areas was undertaken due to inherent inadequacies in the cotton swab-rinse technique to which assay of spacecraft is currently restricted. Four types of contamination control cloths were initially tested. A polyester-bonded cloth (PBC) was selected for further evaluation because of its superior efficiency and handling characteristics. Results from comparative tests with PBC and cotton swabs on simulated spacecraft surfaces indicated a significantly higher recovery efficiency for the PBC than for the cotton (90.4 versus 75.2%). Of the sampling area sites studied, PBC was found to be most effective on surface areas not exceeding 0.74 sq m (8.0 sq ft).
Lanzini, A; De Tavonatti, M G; Panarotto, B; Scalia, S; Mora, A; Benini, F; Baisini, O; Lanzarotto, F
2003-09-01
Whether ileal absorption of bile acid is up or downregulated in chronic cholestasis is still debated, and most evidence has come from animal studies. To compare ileal bile acid absorption in patients with primary biliary cirrhosis (PBC) and in healthy control subjects, and to assess the effect of ursodeoxycholic acid (UDCA). We studied 14 PBC patients before and during (n=11) UDCA administration, 14 healthy control subjects, and 14 Crohn's disease patients (as disease controls). We used cholescintigraphy to measure retention in the enterohepatic circulation over five successive days of the bile acid analogue (75)Se-homocholic acid-taurine ((75)SeHCAT) as an index of ileal bile acid absorption. Results were expressed as (75)SeHCAT fractional turnover rate (FTR) and t(1/2)12. (75)SeHCAT FTR was 0.19 (0.11)/day, 0.34 (0.11)/day (p<0.001), and 0.83 (0.32)/day in PBC patients, healthy controls (p<0.0001), and Crohn's patients (p<0.001), respectively, which increased to 0.36 (0.16)/day in PBC patients during UDCA treatment (p<0.005). (75)SeHCAT t(1/2)12 was 4.8 (2.1) days in PBC patients, 2.2 (0.5) days (p<0.001) in healthy controls, and 1.0 (0.5) days (p<0.001) in Crohn's disease patients. (75)SeHCAT t(1/2)12 decreased to 2.2 (0.93) days (p< 0.001) in PBC patients during UDCA treatment. Our results support the concept that ileal bile acid absorption is upregulated in PBC patients, and that this effect may contribute towards damaging the cholestatic liver. This upregulation of bile acid absorption is abolished by UDCA.
Geoepidemiology, Genetic and Environmental Risk Factors for PBC.
Zhang, Haiyan; Carbone, Marco; Lleo, Ana; Invernizzi, Pietro
2015-01-01
Primary biliary cirrhosis (PBC) is the most paradigmatic autoimmune liver disease with still several controversial issues in epidemiology, diagnosis, causation, and therapy. Although we are witnessing an enormous increase in the quantum of our basic knowledge of the disease with an initial translation in clinical practice, there are still a number of key open questions in PBC. Among them are the following questions: Why are there vast geographical variations in disease frequency? What are the reasons for female preponderance? Why do only small-size bile ducts get affected: What is the real role of genetics and epigenetics in its development? In particular, the prevalence of PBC is known to vary both on an international and a regional level, suggesting the existence of substantive geographical differences in terms of genetic susceptibility and environmental factors. New theories on potential environmental triggers, such as chemical xenobiotics, which lead to the breaking of self-tolerance within a unique immunological milieu of the liver, have been suggested. On the other hand, new and solid data on the genetic architecture of PBC are now obtained from recent high-throughput studies, together with data on sex chromosomes defects, and epigenetic abnormalities, thus strongly suggesting a role of genetic and epigenetic factors in the triggering and perpetuation of the autoimmune aggression in PBC. Based on these evidences, a number of novel drugs directed against specific immune-related molecules are currently under development. In this paper, we review a comprehensive collection of current epidemiological reports from various world regions. We also discuss here the most recent data regarding candidate genetic and environmental risk factors for PBC. © 2015 S. Karger AG, Basel.
Carbone, Marco; Sharp, Stephen J; Flack, Steve; Paximadas, Dimitrios; Spiess, Kelly; Adgey, Carolyn; Griffiths, Laura; Lim, Reyna; Trembling, Paul; Williamson, Kate; Wareham, Nick J; Aldersley, Mark; Bathgate, Andrew; Burroughs, Andrew K; Heneghan, Michael A; Neuberger, James M; Thorburn, Douglas; Hirschfield, Gideon M; Cordell, Heather J; Alexander, Graeme J; Jones, David E J; Sandford, Richard N; Mells, George F
2016-03-01
The biochemical response to ursodeoxycholic acid (UDCA)--so-called "treatment response"--strongly predicts long-term outcome in primary biliary cholangitis (PBC). Several long-term prognostic models based solely on the treatment response have been developed that are widely used to risk stratify PBC patients and guide their management. However, they do not take other prognostic variables into account, such as the stage of the liver disease. We sought to improve existing long-term prognostic models of PBC using data from the UK-PBC Research Cohort. We performed Cox's proportional hazards regression analysis of diverse explanatory variables in a derivation cohort of 1,916 UDCA-treated participants. We used nonautomatic backward selection to derive the best-fitting Cox model, from which we derived a multivariable fractional polynomial model. We combined linear predictors and baseline survivor functions in equations to score the risk of a liver transplant or liver-related death occurring within 5, 10, or 15 years. We validated these risk scores in an independent cohort of 1,249 UDCA-treated participants. The best-fitting model consisted of the baseline albumin and platelet count, as well as the bilirubin, transaminases, and alkaline phosphatase, after 12 months of UDCA. In the validation cohort, the 5-, 10-, and 15-year risk scores were highly accurate (areas under the curve: >0.90). The prognosis of PBC patients can be accurately evaluated using the UK-PBC risk scores. They may be used to identify high-risk patients for closer monitoring and second-line therapies, as well as low-risk patients who could potentially be followed up in primary care. © 2015 by the American Association for the Study of Liver Diseases.
Reactive p-block cations stabilized by weakly coordinating anions
Engesser, Tobias A.; Lichtenthaler, Martin R.; Schleep, Mario
2016-01-01
The chemistry of the p-block elements is a huge playground for fundamental and applied work. With their bonding from electron deficient to hypercoordinate and formally hypervalent, the p-block elements represent an area to find terra incognita. Often, the formation of cations that contain p-block elements as central ingredient is desired, for example to make a compound more Lewis acidic for an application or simply to prove an idea. This review has collected the reactive p-block cations (rPBC) with a comprehensive focus on those that have been published since the year 2000, but including the milestones and key citations of earlier work. We include an overview on the weakly coordinating anions (WCAs) used to stabilize the rPBC and give an overview to WCA selection, ionization strategies for rPBC-formation and finally list the rPBC ordered in their respective group from 13 to 18. However, typical, often more organic ion classes that constitute for example ionic liquids (imidazolium, ammonium, etc.) were omitted, as were those that do not fulfill the – naturally subjective – “reactive”-criterion of the rPBC. As a rule, we only included rPBC with crystal structure and only rarely refer to important cations published without crystal structure. This collection is intended for those who are simply interested what has been done or what is possible, as well as those who seek advice on preparative issues, up to people having a certain application in mind, where the knowledge on the existence of a rPBC that might play a role as an intermediate or active center may be useful. PMID:26612538
Pareja, Fresia; Murray, Melissa P; Jean, Ryan Des; Konno, Fumiko; Friedlander, Maria; Lin, Oscar; Edelweiss, Marcia
2016-01-01
BACKGROUND Discordance in the receptor status between primary breast carcinomas (PBC) and corresponding metastasis is well documented. Interrogation of the receptor status of metastatic breast carcinoma (MBC) in cytology material is common practice; however, its utility has not been thoroughly validated. We studied patients with MBC, and evaluated the concordance rates of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) between PBC surgical specimens and corresponding MBC cell blocks (CBs). We correlated the findings with clinicopathologic variables and with the fixation methods used. METHODS We searched for patients with MBC diagnosed on cytology from 2007 to 2009 and selected those with ER, PR and HER2 tested in both the PBC surgical specimens and the MBC CBs. We included CBs fixed in formalin and methanol based solution (CytoLyt®). All slides were reevaluated by cytopathologists. Clinical information was retrieved from the medical records. RESULTS We studied 65 patients with PBC and MBC paired specimens. The concordance rates between PBC and MBC were 78.5%, 58.5% and 96.9%, for ER, PR and HER2, respectively. When discordant, PR status switched from positive (PBC) to negative (MBC) in most cases (23/27). The PR concordance rate was 45.2% for CBs fixed in formalin and 70.6% for those fixed with CytoLyt® (p=0.047). CONCLUSION The ER, PR and HER2 concordance rates between the PBC and MBC CBs are similar to those reported in paired surgical specimens. PR status was the most prevalent discordance and was not accompanied by a switch in ER. PMID:28529880
Tang, Libo; Zhong, Ruihua; He, Xuanqiu; Wang, Weibin; Liu, Jinhong; Zhu, Youfu; Li, Yongyin; Hou, Jinlin
2017-03-01
Antimitochondrial antibody (AMA) is considered the serological hallmark of primary biliary cholangitis (PBC), while data regarding the profile of AMA during ursodeoxycholic acid (UDCA) treatment are scarce. Here, we assessed the influence of UDCA treatment on titers of AMA and factors relevant to its production. Serum IgA-AMA, IgM-AMA, IgG-AMA, B cell-activating factor of the tumor necrosis factor family (BAFF), and the frequency of circulating plasmablasts were detected in PBC patients, including those who received UDCA therapy for 24 weeks, healthy controls, chronic hepatitis B patients, and autoimmune hepatitis patients. Consecutive liver sections from controls and PBC patients were stained by immunohistochemistry for detection of intrahepatic CD38 + , IgA + , IgM + , and IgG + cells. Significant decrease in titers of IgG-AMA was found only confined to PBC patients with biochemical response to UDCA treatment (P = 0.005), and similar pattern was also observed at week 24 in quantifying circulating plasmablasts (P = 0.025) and serum BAFF (P = 0.013). Notably, positive correlation between serum BAFF levels and titers of IgG-AMA, and the frequency of circulating plasmablasts were observed in PBC patients (r = 0.464, P = 0.034 and r = 0.700, P < 0.001, respectively). Additionally, in situ staining revealed significant accumulation of CD38 + and IgG + cells within the portal tracts of PBC liver. Decreased titers of serum IgG-AMA are associated with biochemical response to UDCA treatment, implicating the potentiality of this hallmark in therapeutic response evaluation and the beneficial effect of UDCA on humoral immunity in PBC patients. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.
Wu, Q-M; Zhao, X-Y; You, H
2016-01-01
Esophageal-gastro Varices (EGV) may develop in any histological stages of primary biliary cirrhosis (PBC). We aim to establish and validate quantitative fibrosis (qFibrosis) parameters in portal, septal and fibrillar areas as ideal predictors of EGV in PBC patients. PBC patients with liver biopsy, esophagogastroscopy and Second Harmonic Generation (SHG)/Two-photon Excited Fluorescence (TPEF) microscopy images were retrospectively enrolled in this study. qFibrosis parameters in portal, septal and fibrillar areas were acquired by computer-assisted SHG/TPEF imaging system. Independent predictor was identified using multivariate logistic regression analysis. PBC patients with liver biopsy, esophagogastroscopy and Second Harmonic Generation (SHG)/Two-photon Excited Fluorescence (TPEF) microscopy images were retrospectively enrolled in this study. qFibrosis parameters in portal, septal and fibrillar areas were acquired by computer-assisted SHG/TPEF imaging system. Independent predictor was identified using multivariate logistic regression analysis. Among the forty-nine PBC patients with qFibrosis images, twenty-nine PBC patients with both esophagogastroscopy data and qFibrosis data were selected out for EGV prognosis analysis and 44.8% (13/29) of them had EGV. The qFibrosis parameters of collagen percentage and number of crosslink in fibrillar area, short/long/thin strings number and length/width of the strings in septa area were associated with EGV (p < 0.05). Multivariate logistic analysis showed that the collagen percentage in fibrillar area ≥ 3.6% was an independent factor to predict EGV (odds ratio 6.9; 95% confidence interval 1.6-27.4). The area under receiver operating characteristic (ROC), diagnostic sensitivity and specificity was 0.9, 100% and 75% respectively. Collagen percentage in Collagen percentage in the fibrillar area as an independent predictor can highly predict EGV in PBC patients.
Braun, Sandra; Berg, Christoph; Buck, Sandra; Gregor, Michael; Klein, Reinhild
2010-02-28
To search for further immunodominant peptides of the pyruvate dehydrogenase complex E2-component (PDC-E2) recognized by antimitochondrial antibodies (AMA) in primary biliary cirrhosis (PBC). Sera from 95 patients with PBC were tested by enzyme-linked immunosorbent assay against 33 synthetic overlapping peptides (25 amino acids; aa) covering the entire length of the E2-subunit of PDC-E2. Furthermore, the inner lipoyl peptide 167-184 was used in an unlipoylated and a lipoylated form as well as coupled to ovalbumin. Sera from 11 AMA negative/ANA positive PBC patients, 63 patients with other liver disorders and 22 healthy blood donors served as controls. Of the 95 PBC-sera, 74% reacted with the peptide 475-499 and 58% with the peptide 407-431 located within the catalytic domain of PDC-E2. Patients with other disorders or healthy controls were positive in only up to 18%. Antibodies to the unlipoylated and lipoylated peptide 167-184 within the inner lipoyl domain were found in only 5% and 11% of the PBC sera, respectively; using ovalbumin-coupled peptides, the incidence increased up to 57% (unlipoylated form). Peptides within the catalytic site of PDC-E2 rather than the previously reported lipoyl binding peptide 167-184 may represent major immunodominant epitopes recognized by AMA in PBC.
Levy, Cynthia; Bowlus, Christopher L; Carey, Elizabeth; Crawford, Julie M; Deane, Karen; Mayo, Marlyn J; Kim, W Ray; Fried, Michael W
2018-05-01
Primary biliary cholangitis (PBC) is a rare chronic cholestatic liver disease that may progress to biliary cirrhosis if left untreated. The first-line therapy for PBC is ursodeoxycholic acid (UDCA). Unfortunately, 1 of 3 patients does not respond to UDCA. These patients are at risk for developing clinical events, including cirrhosis, complications of portal hypertension, hepatocellular carcinoma, liver transplant, or death. Recently, the U.S. Food and Drug Administration approved obeticholic acid to be used in certain patients with PBC. Off-label therapies are also used, and several other therapies are currently under evaluation. Real-world effectiveness of newly approved and off-label therapies remains unknown. TARGET-PBC is a 5-year, longitudinal, observational study of patients with PBC that will evaluate the effectiveness of clinical practice interventions and provide practical information unobtainable in registration trials. Enrollment will take place at both academic and community sites. In addition to consenting to medical records review, participants will be asked to provide an annual blood sample and complete patient reported outcome surveys at predetermined intervals. Any available liver biopsies will be digitally preserved. Conclusion: Key study outcomes will be the evaluation of the safety and effectiveness of PBC interventions and the assessment of disease progression under real-world conditions. ( Hepatology Communications 2018;2:484-491).
Wang, Lijuan; Wang, Lin
2015-01-01
The primary objective of this study was to use the theory of planned behavior (TPB) to examine the association between TPB variables and the moderate-to-vigorous physical activity (MVPA) of children in Shanghai, China. Gender differences were also explored. The participants were 353 children (180 boys and 173 girls) aged 9 to 13 years from three primary schools in Shanghai. Accelerometers were used to measure the MVPA duration of the children. Questionnaires that focused on attitude, subjective norms, and perceived behavioral control (PBC) related to MVPA engagement were completed by the participants. Regression analyses revealed that intention, and not PBC, accounted for 9% of the variance in MVPA. Meanwhile, attitude and PBC explained 33% of the variance in intentions to engage in MVPA. In terms of gender differences, TPB performed better in the physical activity (PA) domain for boys than for girls. Furthermore, attitude and PBC were significantly associated with intention among boys, whereas only PBC was significantly related to intention among girls. Practitioners should consider tailoring intervention to address gender differences to increase leisure-time PA participation of children.
The clinical expression of primary biliary cirrhosis.
Heathcote, J
1997-02-01
Primary biliary cirrhosis (PBC) is likely an autoimmune disease that destroys the interlobular bile ducts. Although the term PBC implies cirrhosis, this is not always present. The condition may be entirely silent clinically, save for the hallmark mitochondrial antibodies in serum. The clinical spectrum of PBC ranges from asymptomatic anicteric cholestasis with or without extrahepatic manifestations to severe cholestasis with decompensated cirrhosis. It is uncertain whether or not the course of this disease is universally fatal. Currently, no specific features have been identified which predict progression from asymptomatic to symptomatic disease, although once hyperbilirubinemia is present, a rising level indicates a poor prognosis. The liver-specific complications include pruritus, abdominal pain, xantholasma, and portal hypertension. The latter is often an early feature, as the portal hypertension is presinusoidal in nature and, when present, does not always reflect the presence of cirrhosis. There are many extrahepatic features of PBC, the most common being metabolic, chiefly hypothyroidism and metabolic bone disease. Other common associations are rheumatologic, renal, pulmonary, neuromuscular, and dermatologic. The non-specific yet distressing symptom of fatigue affects up to two-thirds of PBC subjects, but its etiology remains obscure.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Able, Charles M., E-mail: cable@wfubmc.edu; Bright, Megan; Frizzell, Bart
Purpose: Statistical process control (SPC) is a quality control method used to ensure that a process is well controlled and operates with little variation. This study determined whether SPC was a viable technique for evaluating the proper operation of a high-dose-rate (HDR) brachytherapy treatment delivery system. Methods and Materials: A surrogate prostate patient was developed using Vyse ordnance gelatin. A total of 10 metal oxide semiconductor field-effect transistors (MOSFETs) were placed from prostate base to apex. Computed tomography guidance was used to accurately position the first detector in each train at the base. The plan consisted of 12 needles withmore » 129 dwell positions delivering a prescribed peripheral dose of 200 cGy. Sixteen accurate treatment trials were delivered as planned. Subsequently, a number of treatments were delivered with errors introduced, including wrong patient, wrong source calibration, wrong connection sequence, single needle displaced inferiorly 5 mm, and entire implant displaced 2 mm and 4 mm inferiorly. Two process behavior charts (PBC), an individual and a moving range chart, were developed for each dosimeter location. Results: There were 4 false positives resulting from 160 measurements from 16 accurately delivered treatments. For the inaccurately delivered treatments, the PBC indicated that measurements made at the periphery and apex (regions of high-dose gradient) were much more sensitive to treatment delivery errors. All errors introduced were correctly identified by either the individual or the moving range PBC in the apex region. Measurements at the urethra and base were less sensitive to errors. Conclusions: SPC is a viable method for assessing the quality of HDR treatment delivery. Further development is necessary to determine the most effective dose sampling, to ensure reproducible evaluation of treatment delivery accuracy.« less
Jopson, Laura; Newton, Julia L; Palmer, Jeremy; Floudas, Achilleas; Isaacs, John; Qian, Jessica; Wilkinson, Jennifer; Trenell, Mike; Blamire, Andrew; Howel, Denise; Jones, David E
2015-08-20
Primary biliary cirrhosis (PBC) is an autoimmune liver disease with approximately 50% of patients experiencing fatigue. This can be a particularly debilitating symptom, affecting quality of life and resulting in social isolation. Fatigue is highlighted by patients as a priority for research and patient support groups were involved in designing this trial. This is the first randomised controlled trial to investigate a treatment for fatigue in PBC. The trial protocol is innovative as it utilises novel magnetic resonance spectroscopy (MRS) techniques as an outcome measure. The protocol will be valuable to research groups planning clinical trials targeting fatigue in PBC and also transferrable to other conditions associated with fatigue. RITPBC is a Medical Research Council (MRC) and National Institute for Health Research (NIHR) Efficacy and Mechanism Evaluation Programme (EME)-funded project. It is a phase II, single-centre, randomised controlled, double-blinded trial comparing rituximab with placebo in fatigued PBC patients. 78 patients with PBC and moderate to severe fatigue will be randomised to receive two infusions of rituximab or placebo. The study aims to assess whether rituximab improves fatigue in patients with PBC, the safety, and tolerability of rituximab in PBC and the sustainability of any beneficial actions. The primary outcome will be an improvement in fatigue domain score of the PBC-40, a disease-specific quality of life measure, evaluated at 12-week assessment. Secondary outcome measures include novel MRS techniques assessing muscle bioenergetic function, physical activity, anaerobic threshold and symptom, and quality of life measures. The trial started recruiting in October 2012 and recruitment is ongoing. The trial has ethical approval from the NRES Committee North East, has Clinical Trial Authorisation from MHRA and local R&D approval. Trial results will be communicated to participants, presented at national and international meetings and published in peer-reviewed journals. ISRCTN03978701. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Johnston, Derek W; Johnston, Marie; Pollard, Beth; Kinmonth, Ann-Louise; Mant, David
2004-09-01
Perceived behavioral control (PBC) and intention, the proximal predictors from the theory of planned behavior (TPB), were used to predict cardiovascular risk behaviors in 597 patients 1 year after diagnosis with coronary heart disease. The outcome measures were self-report measures of exercise plus objective measures of fitness (distance walked in 6 min) and cotinine-confirmed smoking cessation. In multivariate analyses incorporating both PBC and intention, PBC predicted exercise, distance walked, and smoking cessation, but intention was not a reliable independent predictor of any health behavior measured. Thus, the effective theoretical component of the TPB was PBC. Similar predictions could derive from social-cognitive theory. In coronary patients, behavioral change needs to address issues of action implementation rather than motivational factors alone. ((c) 2004 APA, all rights reserved)
Stojakovic, Tatjana; Claudel, Thierry; Putz-Bankuti, Csilla; Fauler, Günter; Scharnagl, Hubert; Wagner, Martin; Sourij, Harald; Stauber, Rudolf E; Winkler, Karl; März, Winfried; Wascher, Thomas C; Trauner, Michael
2010-03-01
Primary biliary cirrhosis (PBC) is frequently associated with hypercholesterolemia and with an increased cardiovascular morbidity and mortality. Statins lower serum cholesterol levels and may thus improve the cardiovascular risk in PBC patients. The aim of our study was to prospectively examine the efficacy of low-dose atorvastatin on cholestasis as well as cardiovascular risk markers such as dyslipidemia and vascular function in patients with PBC. Nineteen patients with early-stage (biopsy proven and AMA positive) PBC and low-density lipoprotein cholesterol (LDL-C) above 130mg/dL were included in this single-center study and treated with atorvastatin 10mg per day for one year. Concentrations of total cholesterol, LDL-C, LDL triglycerides, oxLDL, IgG and sVCAM-1 decreased significantly after 48 weeks of atorvastatin treatment. Flow-mediated dilation (FMD) of the brachial artery as an indicator of vascular function significantly increased, while carotid artery intima-media thickness and vascular wall stiffness did not progress under treatment. No statistical differences in liver enzymes were observed except a transient increase of alkaline phosphatase. Treatment with low-dose atorvastatin is safe in early-stage PBC, effectively reduces total cholesterol, LDL-C, LDL triglycerides, oxLDL and sVCAM-1 and improves vascular function as reflected by FMD, without affecting cholestasis progression. Therefore, statin therapy should be considered in PBC patients with additional risk factors for cardiovascular disease.
Assessment of liver function in primary biliary cirrhosis using Gd-EOB-DTPA-enhanced liver MRI.
Nilsson, Henrik; Blomqvist, Lennart; Douglas, Lena; Nordell, Anders; Jonas, Eduard
2010-10-01
Gd-EOB-DTPA (gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid) is a gadolinium-based hepatocyte-specific contrast agent for magnetic resonance imaging (MRI). The aim of this study was to determine whether the hepatic uptake and excretion of Gd-EOB-DTPA differ between patients with primary biliary cirrhosis (PBC) and healthy controls, and whether differences could be quantified. Gd-EOB-DTPA-enhanced liver MRI was performed in 20 healthy volunteers and 12 patients with PBC. The uptake of Gd-EOB-DTPA was assessed using traditional semi-quantitative parameters (C(max) , T(max) and T(1/2) ), as well as model-free parameters derived after deconvolutional analysis (hepatic extraction fraction [HEF], input-relative blood flow [irBF] and mean transit time [MTT]). In each individual, all parameters were calculated for each liver segment and the median of the segmental values was used to define a global liver median (GLM). Although the PBC patients had relatively mild disease according to their Model for End-stage Liver Disease (MELD), Child-Pugh and Mayo risk scores, they had significantly lower HEF and shorter MTT values compared with the healthy controls. These differences significantly increased with increasing MELD and Child-Pugh scores. Dynamic hepatocyte-specific contrast-enhanced MRI (DHCE-MRI) has a potential role as an imaging-based liver function test. The high spatial resolution of MRI enables hepatic function to be assessed on segmental and sub-segmental levels. © 2010 International Hepato-Pancreato-Biliary Association.
NASA Astrophysics Data System (ADS)
Boyarchenkov, A. S.; Potashnikov, S. I.; Nekrasov, K. A.; Kupryazhkin, A. Ya.
2012-08-01
Melting of uranium dioxide (UO2) nanocrystals has been studied by molecular dynamics (MD) simulation. Ten recent and widely used sets of pair potentials were assessed in the rigid ion approximation. Both isolated (in vacuum) and periodic boundary conditions (PBC) were explored. Using barostat under PBC the pressure dependences of melting point were obtained. These curves intersected zero near -20 GPa, saturated near 25 GPa and increased nonlinearly in between. Using simulation of surface under isolated boundary conditions (IBC) recommended melting temperature and density jump were successfully reproduced. However, the heat of fusion is still underestimated. These melting characteristics were calculated for nanocrystals of cubic shape in the range of 768-49 152 particles (volume range of 10-1000 nm3). The obtained reciprocal size dependences decreased nonlinearly. Linear and parabolic extrapolations to macroscopic values are considered. The parabolic one is found to be better suited for analysis of the data on temperature and heat of melting.
Polychronopoulou, Erietta; Lygoura, Vasiliki; Gatselis, Nikolaos K; Dalekos, George N
2017-09-25
Several hepatobiliary disorders have been reported in ulcerative colitis (UC) patients with primary sclerosing cholangitis (PSC) being the most specific. Primary biliary cholangitis (PBC), previously known as primary biliary cirrhosis, rarely occurs in UC. We present two PBC cases of 67 and 71 years who suffered from long-standing UC. Both patients were asymptomatic but they had increased cholestatic enzymes and high titres of antimitochondrial antibodies (AMA)-the laboratory hallmark of PBC. After careful exclusion of other causes of cholestasis by MRI/magnetic resonance cholangiopancreatography (MRCP), virological and microbiological investigations, a diagnosis of PBC associated with UC was established. The patients started ursodeoxycholic acid (13 mg/kg/day) with complete response. During follow-up, both patients remained asymptomatic with normal blood biochemistry. Although PSC is the most common hepatobiliary manifestation among patients with UC, physicians must keep also PBC in mind in those with unexplained cholestasis and repeatedly normal MRCP. In these cases, a reliable AMA testing can help for an accurate diagnosis. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Smyk, Daniel; Mytilinaiou, Maria G; Rigopoulou, Eirini I; Bogdanos, Dimitrios P
2010-01-01
Various environmental factors have been proposed as triggers of primary biliary cirrhosis (PBC), a progressive autoimmune cholestatic liver disease which is characterised by the destruction of the small intrahepatic bile ducts. Support for their pathogenic role in PBC is provided by epidemiological studies reporting familial clustering and clusters of the disease within a given geographical area. The seminal study by Triger reporting that the great majority of PBC cases in the English city of Sheffield drank water from a specific water reservoir, has been followed by studies reporting disease 'hot spots' within a restricted geographic region of the former coal mining area of Newcastle. The New York study reporting an increased risk and significant clustering of PBC cases near toxic federal waste disposal sites has added strength to the notion that environmental factors, possibly in the form of infectious agents or toxic/chemical environmental factors in areas of contaminated land, water or polluted air may play a key role in the development of the disease. This review discusses the findings of reports investigating environmental factors which may contribute to the cause of primary biliary cirrhosis.
Lanzini, A; De Tavonatti, M G; Panarotto, B; Scalia, S; Mora, A; Benini, F; Baisini, O; Lanzarotto, F
2003-01-01
Background: Whether ileal absorption of bile acid is up or downregulated in chronic cholestasis is still debated, and most evidence has come from animal studies. Aims: To compare ileal bile acid absorption in patients with primary biliary cirrhosis (PBC) and in healthy control subjects, and to assess the effect of ursodeoxycholic acid (UDCA). Patients: We studied 14 PBC patients before and during (n=11) UDCA administration, 14 healthy control subjects, and 14 Crohn’s disease patients (as disease controls). Methods: We used cholescintigraphy to measure retention in the enterohepatic circulation over five successive days of the bile acid analogue 75Se-homocholic acid-taurine (75SeHCAT) as an index of ileal bile acid absorption. Results were expressed as 75SeHCAT fractional turnover rate (FTR) and t½12. Results: 75SeHCAT FTR was 0.19 (0.11)/day, 0.34 (0.11)/day (p<0.001), and 0.83 (0.32)/day in PBC patients, healthy controls (p<0.0001), and Crohn’s patients (p<0.001), respectively, which increased to 0.36 (0.16)/day in PBC patients during UDCA treatment (p<0.005). 75SeHCAT t½12 was 4.8 (2.1) days in PBC patients, 2.2 (0.5) days (p<0.001) in healthy controls, and 1.0 (0.5) days (p<0.001) in Crohn’s disease patients. 75SeHCAT t½12 decreased to 2.2 (0.93) days (p< 0.001) in PBC patients during UDCA treatment. Conclusions: Our results support the concept that ileal bile acid absorption is upregulated in PBC patients, and that this effect may contribute towards damaging the cholestatic liver. This upregulation of bile acid absorption is abolished by UDCA. PMID:12912872
Wang, Li; Sun, Xiguang; Qiu, Jinpeng; Cai, Yanjun; Ma, Liang; Zhao, Pingwei; Jiang, Yanfang
2015-02-01
Aberrant activation of follicular helper T (TFH) and B cells is associated with the development of autoimmune diseases. However, little is known about the potential role of these cells in the development of primary biliary cirrhosis (PBC). This study aimed at characterizing the numbers of different subsets of circulating Tfh and B cells as well as evaluating their potential association with the levels of immunoglobulins and autoantibodies in newly diagnosed PBC patients. The numbers of circulating CD27(+), CD38(+), CD86(+) and CD95(+) B cells as well as inducible T cell costimulator (ICOS)(+) and programmed death-1 (PD-1)(+), IL-21(+) TFH cells were examined in 58 patients with newly diagnosed PBC and 30 matched healthy controls (HCs). The numbers of circulating CD38(+)CD19(+), CD86(+)CD19(+), and CD95(+)CD19(+) B cells; CD3(+)CD4(+)CXCR5(+)ICOS(+) and CD3(+)CD4(+)CXCR5(+)PD-1(+) Tfh cells; and the levels of serum IL-21 in the PBC patients were significantly greater, but the numbers of CD27(+)CD19(+) B cells were significantly less than those in the HCs (p < 0.05). The numbers of CD3(+)CD4(+)CXCR5(+)ICOS(+) Tfh cells were positively correlated with the numbers of CD38(+)CD19(+) and CD86(+)CD38(+)CD19(+) B cells and the levels of serum anti-mitochondrial antibodies against M2 antigen (AMA-M2), AMA and immunolgubin M (IgM) in the PBC patients. The levels of serum IL-21 were positively correlated with the levels of serum AMA-M2, AMA, IgG and IgM, but negatively with the numbers of CD27(+)CD19(+) B cells in the PBC patients. Increased numbers of circulating ICOS(+) and IL-21(+) Tfh and CD38(+) plasma cells may be exhibited by patients with recent diagnoses of PBC.
U-Pb Dating of Calcite by LA-ICPMS
NASA Astrophysics Data System (ADS)
Hacker, B. R.; Kylander-Clark, A. R.; Holder, R. M.; Nuriel, P.
2016-12-01
An emerging frontier area in geochronology is U-Pb dating of carbonate minerals by laser-ablation inductively coupled plasma mass spectrometry (LA-ICPMS). The spate of papers over the last few years applying LA-ICPMS to carbonate dating stems from the capability of LA-ICPMS to deal with the variable, and often low, U/Pb ratios of carbonate. LA-ICPMS is an excellent tool for efficiently screening out samples with low U/Pb ratios and provides the ability to measure many spots with different U/Pb ratios and obtain dates free of assumptions about the composition of common Pb. Because this technique is in its infancy, important questions remain. What percentage of carbonate samples have high enough U/Pbc ratios that they can be dated? What percentage of samples yield isochronous datasets? What are the limits on precision and accuracy of carbonate U/Pb dates? What is the best analytical method in the absence of isotopically homogeneous reference materials? Through the generosity of our colleagues we have acquired 8 reference materials ranging in age from 3 to 250 Ma. We have analyzed 125 unknowns from a variety of locations using a 193 nm ns laser with an 80-100 μm spot and a Nu Plasma HR-ES. We measure 207Pb/206Pb using NIST 614 glass and then calculate a 206Pb/238U correction factor based on the measured vs. known ages of the reference materials. Sixty of these samples ( 50%) have high enough U/Pb ratios that they can be dated. There is great heterogeneity among the sample suites: some have no datable samples, whereas one suite of 68 samples yielded 53 datable rocks. Of the samples with high U/Pbc ratios, a majority yielded isochronous U-Pb data, indicating that the U-Pb system closed at a given time and was not subsequently disturbed.
Grover, V P B; Southern, L; Dyson, J K; Kim, J U; Crossey, M M E; Wylezinska-Arridge, M; Patel, N; Fitzpatrick, J A; Bak-Bol, A; Waldman, A D; Alexander, G J; Mells, G F; Chapman, R W; Jones, D E J; Taylor-Robinson, S D
2016-11-01
Brain change can occur in primary biliary cholangitis (PBC), potentially as a result of cholestatic and/or inflammatory processes. This change is linked to systemic symptoms of fatigue and cognitive impairment. To identify whether brain change occurs early in PBC. If the change develops early and is progressive, it may explain the difficulty in treating these symptoms. Early disease brain change was explored in 13 patients with newly diagnosed biopsy-proven precirrhotic PBC using magnetisation transfer, diffusion-weighted imaging and 1 H magnetic resonance spectroscopy. Results were compared to 17 healthy volunteers. Cerebral magnetisation transfer ratios were reduced in early PBC, compared to healthy volunteers, in the thalamus, putamen and head of caudate with no greater reduction in patients with greater symptom severity. Mean apparent diffusion coefficients were increased in the thalamus only. No 1 H magnetic resonance spectroscopy abnormalities were seen. Serum manganese levels were elevated in all PBC patients, but no relationship was seen with imaging or symptom parameters. There were no correlations between neuroimaging data, laboratory data, symptom severity scores or age. This is the first study to be performed in this precirrhotic patient population, and we have highlighted that neuroimaging changes are present at a much earlier stage than previously demonstrated. The neuroimaging abnormalities suggest that the brain changes seen in PBC occur early in the pathological process, even before significant liver damage has occurred. If such changes are linked to symptom pathogenesis, this could have important implications for the timing of second-line-therapy use. © 2016 The Authors. Alimentary Pharmacology & Therapeutics published by John Wiley & Sons Ltd.
Lammert, Craig; Juran, Brian D.; Schlicht, Erik; Xie, Xiao; Atkinson, Elizabeth J.; de Andrade, Mariza; Lazaridis, Konstantinos N.
2014-01-01
Background & Aims Coffee consumption has been associated with decreased risk of liver disease and related outcomes. However, coffee drinking has not been investigated among patients with cholestatic autoimmune liver diseases, primary biliary cirrhosis (PBC), or primary sclerosing cholangitis (PSC). We investigated the relationship between coffee consumption and risk of PBC and PSC in a large North American cohort. Methods Lifetime coffee drinking habits were determined from responses to questionnaires from 606 patients with PBC, 480 with PSC, and 564 healthy volunteers (controls). Patients (those with PBC or PSC) were compared to controls utilizing the Wilcoxon rank sum test for continuous variables and c2 method for discrete variables. Logistic regression was used to analyze the estimate the effects of different coffee parameters (time, frequency, and type of coffee consumption) after adjusting for age, sex, smoking status, and education level. Results Patients with PBC and controls did not differ in coffee parameters. However, 24% of patients with PSC had never drank coffee compared to 16% of controls (P<.05), and only 67% were current drinkers compared with 77% of controls (P<.05). Patients with PSC also consumed fewer lifetime cups per month (45 vs 47 for controls, P<.05) and spent a smaller percentage of their lifetime of coffee drinking coffee (46.6% vs 66.7% for controls, P<.05). These differences remained significant in a multivariate model. Among PSC patients with concurrent ulcerative colitis, coffee protected against proctocolectomy (hazard ratio=0.34, P<.001). Conclusions Coffee consumption is lower among patients with PSC, but not PBC, compared to controls. PMID:24440215
De Nardi, Massimo; Pizzigalli, Luisa; Benis, Roberto; Caffaro, Federica; Micheletti Cremasco, Margherita
2017-12-01
De Nardi, M, Pizzigalli, L, Benis, R, Caffaro, F, and Cremasco, MM. Acute effects of partial-body cryotherapy on isometric strength: maximum handgrip strength evaluation. J Strength Cond Res 31(12): 3497-3502, 2017-The aim of the study was to evaluate the influence of a single partial-body cryotherapy (PBC) session on the maximum handgrip strength (JAMAR Hydraulic Hand dynamometer). Two hundred healthy adults were randomized into a PBC group and a control group (50 men and 50 women in each group). After the initial handgrip strength test (T0), the experimental group performed a 150-second session of PBC (temperature range between -130 and -160° C), whereas the control group stayed in a thermo neutral room (22.0 ± 0.5° C). Immediately after, both groups performed another handgrip strength test (T1). Data underlined that both groups showed an increase in handgrip strength values, especially the experimental group (Control: T0 = 39.48 kg, T1 = 40.01 kg; PBC: T0 = 39.61 kg, T1 = 41.34 kg). The analysis also reported a statistical effect related to gender (F = 491.99, P ≤ 0.05), with women showing lower handgrip strength values compared with men (women = 30.43 kg, men = 52.27 kg). Findings provide the first evidence that a single session of PBC leads to the improvement of muscle strength in healthy people. The results of the study imply that PBC could be performed also before a training session or a sport competition, to increase hand isometric strength.
Louis, Julien; Schaal, Karine; Bieuzen, François; Le Meur, Yann; Filliard, Jean-Robert; Volondat, Marielle; Brisswalter, Jeanick; Hausswirth, Christophe
2015-01-01
Recent research on whole-body cryotherapy has hypothesized a major responsibility of head cooling in the physiological changes classically reported after a cryostimulation session. The aim of this experiment was to verify this hypothesis by studying the influence of exposing the head to cold during whole-body cryostimulation sessions, on the thermal response and the autonomic nervous system (ANS). Over five consecutive days, two groups of 10 participants performed one whole-body cryostimulation session daily, in one of two different systems; one exposing the whole-body to cold (whole-body cryostimulation, WBC), and the other exposing the whole-body except the head (partial-body cryostimulation, PBC).10 participants constituted a control group (CON) not receiving any cryostimulation. In order to isolate the head-cooling effect on recorded variables, it was ensured that the WBC and PBC systems induced the same decrease in skin temperature for all body regions (mean decrease over the 5 exposures: -8.6°C ± 1.3°C and -8.3 ± 0.7°C for WBC and PBC, respectively), which persisted up to 20-min after the sessions (P20). The WBC sessions caused an almost certain decrease in tympanic temperature from Pre to P20 (-0.28 ± 0.11°C), while it only decreased at P20 (-0.14 ± 0.05°C) after PBC sessions. Heart rate almost certainly decreased after PBC (-8.6%) and WBC (-12.3%) sessions. Resting vagal-related heart rate variability indices (the root-mean square difference of successive normal R-R intervals, RMSSD, and high frequency band, HF) were very likely to almost certainly increased after PBC (RMSSD:+49.1%, HF: +123.3%) and WBC (RMSSD: +38.8%, HF:+70.3%). Plasma norepinephrine concentration was likely increased in similar proportions after PBC and WBC, but only after the first session. Both cryostimulation techniques stimulated the ANS with a predominance of parasympathetic tone activation from the first to the fifth session and in slightly greater proportion with WBC than PBC. The main result of this study indicates that the head exposure to cold during whole-body cryostimulation may not be the main factor responsible for the effects of cryostimulation on the ANS.
Louis, Julien; Schaal, Karine; Bieuzen, François; Le Meur, Yann; Filliard, Jean-Robert; Volondat, Marielle; Brisswalter, Jeanick; Hausswirth, Christophe
2015-01-01
Recent research on whole-body cryotherapy has hypothesized a major responsibility of head cooling in the physiological changes classically reported after a cryostimulation session. The aim of this experiment was to verify this hypothesis by studying the influence of exposing the head to cold during whole-body cryostimulation sessions, on the thermal response and the autonomic nervous system (ANS). Over five consecutive days, two groups of 10 participants performed one whole-body cryostimulation session daily, in one of two different systems; one exposing the whole-body to cold (whole-body cryostimulation, WBC), and the other exposing the whole-body except the head (partial-body cryostimulation, PBC).10 participants constituted a control group (CON) not receiving any cryostimulation. In order to isolate the head-cooling effect on recorded variables, it was ensured that the WBC and PBC systems induced the same decrease in skin temperature for all body regions (mean decrease over the 5 exposures: -8.6°C±1.3°C and -8.3±0.7°C for WBC and PBC, respectively), which persisted up to 20-min after the sessions (P20). The WBC sessions caused an almost certain decrease in tympanic temperature from Pre to P20 (-0.28 ±0.11°C), while it only decreased at P20 (-0.14±0.05°C) after PBC sessions. Heart rate almost certainly decreased after PBC (-8.6%) and WBC (-12.3%) sessions. Resting vagal-related heart rate variability indices (the root-mean square difference of successive normal R-R intervals, RMSSD, and high frequency band, HF) were very likely to almost certainly increased after PBC (RMSSD:+49.1%, HF: +123.3%) and WBC (RMSSD: +38.8%, HF:+70.3%). Plasma norepinephrine concentration was likely increased in similar proportions after PBC and WBC, but only after the first session. Both cryostimulation techniques stimulated the ANS with a predominance of parasympathetic tone activation from the first to the fifth session and in slightly greater proportion with WBC than PBC. The main result of this study indicates that the head exposure to cold during whole-body cryostimulation may not be the main factor responsible for the effects of cryostimulation on the ANS. PMID:25915642
Association of primary biliary cirrhosis with the allele HLA-DPB1*0301 in a German population.
Mella, J G; Roschmann, E; Maier, K P; Volk, B A
1995-02-01
The major histocompatibility complex class II alleles at the HLA-DPB1 locus were investigated in 32 German Caucasoid patients with primary biliary cirrhosis (PBC) and compared with those from 47 normal control patients using molecular genotyping techniques. The second exon of the HLA-DPB1 gene was amplified by polymerase chain reaction (PCR) and hybridized with 25 sequence-specific oligonucleotides (SSOs) to assign the HLA-DPB1 alleles on the basis of known sequence variations, according to the protocols of the Eleventh International Histocompatibility Workshop. A strong association of PBC was found with the allele HLA-DPB1*0301. The allele HLA DPB1*0301 was present in 50% (16 of 32) of the patients with PBC compared with 13% (6 of 47) of normal controls (P corrected < .015), whereas the other HLA-DPB1 alleles showed no significant differences in both groups. The relative risk (RR) estimate for the allele HLA-DPB1*0301 was 6.8 (95% confidence limits: 2.27 to 20.57). In summary, this study clearly demonstrates an association of PBC with the HLA-DPB1*0301 allele in German Caucasoids and may add new data to the immunogenetic background of PBC, suggesting a contribution of the HLA-DPB1 gene to the genetic susceptibility of the disease.
Dilger, Karin; Hohenester, Simon; Winkler-Budenhofer, Ursula; Bastiaansen, Barbara A J; Schaap, Frank G; Rust, Christian; Beuers, Ulrich
2012-07-01
Ursodeoxycholic acid (UDCA) exerts anticholestatic, antifibrotic and antiproliferative effects in primary biliary cirrhosis (PBC) via mechanisms not yet fully understood. Its adequate biliary enrichment is considered mandatory for therapeutic efficacy. However, precise determination of biliary enrichment of UDCA is not possible in clinical practice. Therefore, we investigated (i) the relationship between biliary enrichment and plasma pharmacokinetics of UDCA, (ii) the effect of UDCA on plasma and biliary bile acid composition and conjugation patterns, and (iii) on the intestinal detoxification machinery in patients with PBC and healthy controls. In 11 PBC patients and 11 matched healthy subjects, cystic bile and duodenal tissue were collected before and after 3 weeks of administration of UDCA (15 mg/kg/day). Extensive pharmacokinetic profiling of bile acids was performed. The effect of UDCA on the intestinal detoxification machinery was studied by quantitative PCR and Western blotting. The relative fraction of UDCA and its conjugates in plasma at trough level[x] correlated with their biliary enrichment[y] (r=0.73, p=0.0001, y=3.65+0.49x). Taurine conjugates of the major hydrophobic bile acid, chenodeoxycholic acid, were more prominent in bile of PBC patients than in that of healthy controls. Biliary bile acid conjugation patterns normalized after treatment with UDCA. UDCA induced duodenal expression of key export pumps, BCRP and P-glycoprotein. Biliary and trough plasma enrichment of UDCA are closely correlated in PBC and health. Taurine conjugation may represent an adaptive mechanism in PBC against chenodeoxycholic acid-mediated bile duct damage. UDCA may stabilize small intestinal detoxification by upregulation of efflux pumps. Copyright © 2012. Published by Elsevier B.V.
The theory of planned behaviour and discrete food choices: a systematic review and meta-analysis.
McDermott, Máirtín S; Oliver, Madalyn; Svenson, Alexander; Simnadis, Thomas; Beck, Eleanor J; Coltman, Tim; Iverson, Don; Caputi, Peter; Sharma, Rajeev
2015-12-30
The combination of economic and social costs associated with non-communicable diseases provide a compelling argument for developing strategies that can influence modifiable risk factors, such as discrete food choices. Models of behaviour, such as the Theory of Planned Behaviour (TPB) provide conceptual order that allows program designers and policy makers to identify the substantive elements that drive behaviour and design effective interventions. The primary aim of the current review was to examine the association between TPB variables and discrete food choice behaviours. A systematic literature search was conducted to identify relevant studies. Calculation of the pooled mean effect size (r(+)) was conducted using inverse-variance weighted, random effects meta-analysis. Heterogeneity across studies was assessed using the Q- and I(2)-statistics. Meta-regression was used to test the impact of moderator variables: type of food choice behaviour; participants' age and gender. A total of 42 journal articles and four unpublished dissertations met the inclusion criteria. TPB variables were found to have medium to large associations with both intention and behaviour. Attitudes had the strongest association with intention (r(+) = 0.54) followed by perceived behavioural control (PBC, r(+) = 0.42) and subjective norm (SN, r(+) = 0.37). The association between intention and behaviour was r(+) = 0.45 and between PBC and behaviour was r(+) = 0.27. Moderator analyses revealed the complex nature of dietary behaviour and the factors that underpin individual food choices. Significantly higher PBC-behaviour associations were found for choosing health compromising compared to health promoting foods. Significantly higher intention-behaviour and PBC-behaviour associations were found for choosing health promoting foods compared to avoiding health compromising foods. Participant characteristics were also found to moderate associations within the model. Higher intention-behaviour associations were found for older, compared to younger age groups. The variability in the association of the TPB with different food choice behaviours uncovered by the moderator analyses strongly suggest that researchers should carefully consider the nature of the behaviour being exhibited prior to selecting a theory.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, J; Chung, J
2015-06-15
Purpose: To verify delivered doses on the implanted cardiac pacemaker, predicted doses with and without dose reduction method were verified using the MOSFET detectors in terms of beam delivery and dose calculation techniques in intensity-modulated radiation therapy (IMRT). Methods: The pacemaker doses for a patient with a tongue cancer were predicted according to the beam delivery methods [step-and-shoot (SS) and sliding window (SW)], intensity levels for dose optimization, and dose calculation algorithms. Dosimetric effects on the pacemaker were calculated three dose engines: pencil-beam convolution (PBC), analytical anisotropic algorithm (AAA), and Acuros-XB. A lead shield of 2 mm thickness was designedmore » for minimizing irradiated doses to the pacemaker. Dose variations affected by the heterogeneous material properties of the pacemaker and effectiveness of the lead shield were predicted by the Acuros-XB. Dose prediction accuracy and the feasibility of the dose reduction strategy were verified based on the measured skin doses right above the pacemaker using mosfet detectors during the radiation treatment. Results: The Acuros-XB showed underestimated skin doses and overestimated doses by the lead-shield effect, even though the lower dose disagreement was observed. It led to improved dose prediction with higher intensity level of dose optimization in IMRT. The dedicated tertiary lead sheet effectively achieved reduction of pacemaker dose up to 60%. Conclusion: The current SS technique could deliver lower scattered doses than recommendation criteria, however, use of the lead sheet contributed to reduce scattered doses.Thin lead plate can be a useful tertiary shielder and it could not acuse malfunction or electrical damage of the implanted pacemaker in IMRT. It is required to estimate more accurate scattered doses of the patient with medical device to design proper dose reduction strategy.« less
Saddle-node bifurcation to jammed state for quasi-one-dimensional counter-chemotactic flow.
Fujii, Masashi; Awazu, Akinori; Nishimori, Hiraku
2010-07-01
The transition of a counter-chemotactic particle flow from a free-flow state to a jammed state in a quasi-one-dimensional path is investigated. One of the characteristic features of such a flow is that the constituent particles spontaneously form a cluster that blocks the path, called a path-blocking cluster (PBC), and causes a jammed state when the particle density is greater than a threshold value. Near the threshold value, the PBC occasionally collapses on itself to recover the free flow. In other words, the time evolution of the size of the PBC governs the flux of a counter-chemotactic flow. In this Rapid Communication, on the basis of numerical results of a stochastic cellular automata (SCA) model, we introduce a Langevin equation model for the size evolution of the PBC that reproduces the qualitative characteristics of the SCA model. The results suggest that the emergence of the jammed state in a quasi-one-dimensional counterflow is caused by a saddle-node bifurcation.
Gou, Changlong; Wang, Yuqiong; Zhang, Xiqing; Lou, Yujie; Gao, Yunhang
2017-11-01
The objective was to determine the effects of psychrotrophic-thermophilic complex microbial agent (PTCMA) comprised of a psychrotrophic bacterium consortium (PBC) and a thermophilic cellulolytic fungi consortium (TCFC), on composting in a cold climate. Mixtures of dairy manure and rice straw were inoculated with PTCMA, PBC, TCFC and sterile water (control) and composted at an initial ambient temperatures of -2 to 5°C. In compost piles inoculated with PBC or PTCMA, temperatures reached the thermophilic phase (>55°C) faster (8-11d) than piles inoculated with TCFC or control. Furthermore, compost inoculated with TCFC or PTCMA had greater decreases in total organic carbon and carbon-to-nitrogen ratios, as well as significant increases in total nitrogen, degradation of cellulose and lignin and germination index than PBC inoculation or Control compost. Consequently, inoculation with both (i.e. PTCMA) accelerated the onset and promoted maturity of composting under cold-climate conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.
Myositis with antimitochondrial antibodies diagnosed by rectus abdominis muscle biopsy.
Uenaka, Takeshi; Kowa, Hisatomo; Sekiguchi, Kenji; Nagata, Kakuya; Ohtsuka, Yoshihisa; Kanda, Fumio; Toda, Tatsushi
2013-05-01
Antimitochondrial antibodies are autoantibodies detected in 90% of primary biliary cirrhosis (PBC) patients. Some PBC cases are complicated by myositis, which is difficult to confirm due to minimal histological evidence of inflammation in limb muscles. Our aim was to determine the extent of inflammatory changes in a truncal muscle biopsy specimen from a PBC patient. A 48-year-old woman with a 5-year history of atrial fibrillation and chronic heart failure was evaluated for elevated serum creatine kinase level. Antimitochondrial M2 antibodies were detected, and PBC was diagnosed. A biceps brachii biopsy specimen showed mild, non-specific myogenic changes; a second biopsy was performed on the rectus abdominis muscle, which showed typical inflammatory changes. Myositis with antimitochondrial M2 antibodies was confirmed. In myositis patients with antimitochondrial M2 antibodies, muscles of the extremities are involved to a lesser extent. Radiological and histological examination focusing on truncal muscles, including a biopsy, is important. Copyright © 2012 Wiley Periodicals, Inc.
Bassett-Gunter, Rebecca L; Levy-Milne, Ryna; Naylor, Patti Jean; Symons Downs, Danielle; Benoit, Cecilia; Warburton, Darren E R; Blanchard, Chris M; Rhodes, Ryan E
2013-07-06
Transitioning to parenthood is a major life event that may impact parents' personal lifestyles, yet there is an absence of theory-based research examining the impact of parenthood on motives for dietary behaviour. As a result, we are unaware of the social cognitive variables that predict eating behaviour among those transitioning to parenthood. The purpose of the study was to examine eating behaviour motives across 12 months within the framework of the theory of planned behavior (TPB) and compare these across groups of new parents, non-parents, and established parents. Non-parents (n = 92), new parents (n = 135), and established parents (n = 71) completed TPB questionnaires assessing attitudes, subjective norms, perceived behavioral control (PBC), and intentions and three day food records at baseline, and 6- and 12-months post-delivery (for parents) and 6- and 12-months post-baseline (for non-parents). Repeated measures ANOVAs revealed that among men, new- and established-parents had greater intentions to eat healthy compared to non-parents, F(2) = 3.59, p = .03. Among women, established parents had greater intentions than new- and non-parents, F(2) = 5.33, p = .01. Among both men and women during the first 6-months post-delivery, new-parents experienced decreased PBC, whereas established parents experienced increased PBC. Overall, affective attitudes were the strongest predictor of intentions for men (β = 0.55, p < .001) and women (β = 0.38, p < .01). PBC predicted changes in fruit and vegetable consumption for men (β = 0.45, p = .02), and changes in fat consumption for men (β = -0.25, p = .03) and women (β = -.24, p < .05), regardless of parent status. The transition to parenthood for new and established parents may impact motivation for healthy eating, especially PBC within the framework of TPB. However, regardless of parental status, affective attitudes and PBC are critical antecedents of intentions and eating behaviour. Interventions should target affective attitudes and PBC to motivate healthy eating and may need to be intensified during parenthood.
[Primary biliary cirrhosis-autoimmune hepatitis overlap syndrome. Contribution of two new cases].
Fernández Fernández, F J; de la Fuente Aguado, J; Pérez Fernández, S; Sopeña Pérez-Argüelles, B; Nodar Germiñas, A; Butrón Vila, M
2005-03-01
The autoimmune hepatitis (AIH)-primary biliary cirrhosis (PBC) overlap syndrome is characterized for clinical, biochemical, immunological, and histological features overlapping those of AIH and PBC, whose pathogenesis and more appropriate treatment are unknown at present. We describe two new patients of this entity, which made debut with cholestasic acute hepatitis accompanied of hypergammaglobulinemia. In the first patient was demonstrated the presence of AMA, ASMA, and anti-LKM1 autoantibodies; and ANA in the second one. The histological findings showed changes suggestive of AIH and PBC. After the start of immunosuppressive treatment, associated to ursodeoxycholic acid in one patient, a successful outcome was observed.
Beam control of high-power broad-area photonic crystal lasers using ladderlike groove structure
NASA Astrophysics Data System (ADS)
Wang, Tao; Wang, Lijie; Shu, Shili; Tian, Sicong; Lu, Zefeng; Hou, Guanyu; Lu, Huanyu; Tong, Cunzhu; Wang, Lijun
2017-06-01
The high-power broad-area (BA) photonic bandgap crystal (PBC) diode laser is promising as a high-brightness laser source, however, it suffers from poor lateral beam quality owing to the intrinsic drawback of BA lasers. In this paper, a ladderlike groove structure (LLGS) was proposed to improve both the lateral beam quality and emission power of BA PBC lasers. An approximately 15.4% improvement in output power and 25.2% decrease in the lateral beam parameter product (BPP) were realized and the underlying mechanism was discussed. On the basis of the one-dimensional PBC epitaxial structure, a stable vertical far field was demonstrated.
Evaluation of six TPS algorithms in computing entrance and exit doses.
Tan, Yun I; Metwaly, Mohamed; Glegg, Martin; Baggarley, Shaun; Elliott, Alex
2014-05-08
Entrance and exit doses are commonly measured in in vivo dosimetry for comparison with expected values, usually generated by the treatment planning system (TPS), to verify accuracy of treatment delivery. This report aims to evaluate the accuracy of six TPS algorithms in computing entrance and exit doses for a 6 MV beam. The algorithms tested were: pencil beam convolution (Eclipse PBC), analytical anisotropic algorithm (Eclipse AAA), AcurosXB (Eclipse AXB), FFT convolution (XiO Convolution), multigrid superposition (XiO Superposition), and Monte Carlo photon (Monaco MC). Measurements with ionization chamber (IC) and diode detector in water phantoms were used as a reference. Comparisons were done in terms of central axis point dose, 1D relative profiles, and 2D absolute gamma analysis. Entrance doses computed by all TPS algorithms agreed to within 2% of the measured values. Exit doses computed by XiO Convolution, XiO Superposition, Eclipse AXB, and Monaco MC agreed with the IC measured doses to within 2%-3%. Meanwhile, Eclipse PBC and Eclipse AAA computed exit doses were higher than the IC measured doses by up to 5.3% and 4.8%, respectively. Both algorithms assume that full backscatter exists even at the exit level, leading to an overestimation of exit doses. Despite good agreements at the central axis for Eclipse AXB and Monaco MC, 1D relative comparisons showed profiles mismatched at depths beyond 11.5 cm. Overall, the 2D absolute gamma (3%/3 mm) pass rates were better for Monaco MC, while Eclipse AXB failed mostly at the outer 20% of the field area. The findings of this study serve as a useful baseline for the implementation of entrance and exit in vivo dosimetry in clinical departments utilizing any of these six common TPS algorithms for reference comparison.
Statins in primary biliary cirrhosis: are they safe?
Abu Rajab, Murad; Kaplan, Marshall M
2010-07-01
Although cholesterol levels are elevated in patients with primary biliary cirrhosis (PBC), most PBC patients are not at increased risk of dying from atherosclerotic heart disease. There is, however, a subgroup, approximately 10%, who have additional disorders of lipid metabolism. They might benefit from a cholesterol-lowering agent. However, there is concern about using statins in patients with pre-existing liver disease. We therefore reviewed our experience with statins in a large cohort of PBC patients who were seen at Tufts Medical Center during the past decade. From January 1, 1996, until June 30, 2006, 603 patients with PBC were seen by one of us (M.M.K.). Fifty-eight were on statins and five were on ezetimibe. The mean duration of usage was 41 months (range 3-125 months). Alanine aminotransferase (ALT) levels were measured at 3-month intervals. Statins were well tolerated. No patient complained of muscle pain or weakness. There was no increase in ALT levels. ALT levels were slightly elevated at the time that statins were begun (41.7 +/- 25.1 U/l), and were normal at the last time these patients were seen (39.0 +/- 21.0 U/l) (P
Shimoda, Shinji; Miyakawa, Hiroshi; Nakamura, Minoru; Ishibashi, Hiromi; Kikuchi, Kentaro; Kita, Hiroto; Niiro, Hiroaki; Arinobu, Youjirou; Ono, Nobuyuki; Mackay, Ian R; Gershwin, M Eric; Akashi, Koichi
2008-09-01
Approximately 5% of patients with primary biliary cirrhosis (PBC) lack characteristic anti-mitochondrial antibodies (AMA). Yet clinically AMA+ and AMA- patients are similar. Using both AMA+ and AMA- patients, we quantitated the frequency of autoreactive T cells that respond to the major CD4 T-cell epitope, PDC-E2 163-176, using limiting dilution assays and quantitation of IFN-gamma, IL-10 and IL-4. Further, based on data that both PBC patients and healthy subjects have CD4+ T cells that recognize PDC-E2 163-176 but with differing costimulation requirements, assays were performed using two different antigen-presenting cell (APC) systems: either autologous peripheral blood mononuclear cells (PBMC) or HLA DR53 transfected mouse fibroblast cell lines (L-DR53). When costimulation-incompetent L-DR53 were used as APCs, the PDC-E2 CD4 T-cell frequency and capacity for IFN-gamma production were equivalent in both AMA+ and AMA- patients but the frequencies of such cells were significantly lower in normals, with IL-10 production similar in all three groups. Thus, in PBC there is 'universal' autoreactive CD4+ T-cell immune responsiveness to the critical autoantigen, PDC-E2. These observations emphasize that the mitochondrial autoreactivity in PBC is a multi-lineage response and hence, AMA-negative PBC may be an anachronism that refers only to sera autoantibodies.
Qu, Xiangyang; Cao, Yujiang; Chen, Cong; Die, Xiaohong; Kang, Quan
2014-12-10
We explored a novel biodegradable poly (lactide-co-glycolide) (PLGA) film loaded with over 80 wt% bone morphogenetic protein (BMP-2), which was regarded as a substrate promoting osteoblast attachment, proliferation and differentiation for application of bone tissue engineering. Using phospholipid as a surfactant, BMP-2 was modified as a complex (PBC) for dispersing in PLGA/dichloromethane solution. The PLGA film loaded with BMP-2 and phospholipid complex (PBC-PF) showed rough and draped morphology with high entrapment efficiency exceeding 80% and good hydrophilicity respectively. The in-vitro release study of BMP-2 showed that about 50% BMP-2 was slowly and continuously released from PBC-PF within 5 weeks and had a short initial burst release only in the last 1.5 days, which was better than serious burst release of PLGA film loaded with pure BMP-2 without phospholipid (BMP-PF) controlling. By comparison with other PLGA films and tissue culture plates, it was confirmed that PBC-PF significantly promoted the attachment, proliferation and differentiation of osteoblasts with higher entrapment efficiency and better sustained release. These advantages illustrated that PBC-PF could be a potential substrate providing long-term requisite growth factors for osteoblasts, which might be applied in bone tissue engineering. This article is protected by copyright. All rights reserved. Copyright © 2014 Wiley Periodicals, Inc., A Wiley Company.
Qu, Xiangyang; Cao, Yujiang; Chen, Cong; Die, Xiaohong; Kang, Quan
2015-08-01
We explored a novel biodegradable poly(lactide-co-glycolide) (PLGA) film loaded with over 80 wt % bone morphogenetic protein (BMP)-2, which was regarded as a substrate-promoting osteoblast attachment, proliferation, and differentiation for application of bone tissue engineering. Using phospholipid as a surfactant, BMP-2 was modified as a complex (PBC) for dispersing in PLGA/dichloromethane solution. The PLGA film loaded with BMP-2 and phospholipid complex (PBC-PF) showed rough and draped morphology with high entrapment efficiency exceeding 80% and good hydrophilicity, respectively. The in vitro release study of BMP-2 showed that about 50% BMP-2 was slowly and continuously released from PBC-PF within 5 weeks and had a short initial burst release only in the last 1.5 days, which was better than serious burst release of PLGA film loaded with pure BMP-2 without phospholipid (BMP-PF) as control. By comparison with other PLGA films and tissue culture plates, it was confirmed that PBC-PF significantly promoted the attachment, proliferation, and differentiation of osteoblasts with higher entrapment efficiency and better sustained release. These advantages illustrated that PBC-PF could be a potential substrate providing long-term requisite growth factors for osteoblasts, which might be applied in bone tissue engineering. © 2015 Wiley Periodicals, Inc.
Kothe, Emily J; Mullan, Barbara A
2015-09-01
The theory of planned behaviour (TPB) has been criticized for not including interactions between major constructs thought to underlie behaviour. This study investigated the application of the TPB to the prediction of fruit and vegetable consumption across three prospective cohorts. The primary aim of the study was to investigate whether interactions between major constructs in the theory would increase the ability of the model to predict intention to consume fruit and vegetables (i.e., attitude × perceived behavioural control [PBC], subjective norm × PBC, subjective norm × attitude) and self-reported fruit and vegetable intake (i.e., PBC × intention). Secondary data analysis from three cohorts: One predictive study (cohort 1) and two intervention studies (cohorts 2 and 3). Participants completed a TPB measure at baseline and a measure of fruit and vegetable intake at 1 week (cohort 1; n = 90) or 1 month (cohorts 2 and 3; n = 296). Attitude moderated the impact of PBC on intention. PBC moderated the impact of intention on behaviour at 1 week but not 1 month. The variance accounted for by the interactions was small. However, the presence of interactions between constructs within the TPB demonstrates a need to consider interactions between variables within the TPB in both theoretical and applied research using the model. © 2014 The British Psychological Society.
What Comes after Ursodeoxycholic Acid in Primary Biliary Cholangitis?
Wong, Lin Lee; Hegade, Vinod S; Jones, David E J
2017-01-01
Primary biliary cholangitis (PBC) is a rare autoimmune liver disease characterized by chronic cholestasis. Treatment with the accepted primary therapy ursodeoxycholic acid (UDCA) has been shown to be associated with delayed disease progression probably through reduced impact of cholestatic injury on the target biliary epithelial cells. Patients with inadequate response to UDCA (which can be identified through validated biochemical criteria) are at increased risk of disease progression, need for liver transplantation, and death. Obeticholic acid (OCA) is a farnesoid X receptor (FXR) agonist which has been evaluated as a second-line therapy in PBC and has been recently licensed by the Food and Drug Administration and European Medicines Agency for use in patients showing an inadequate response to UDCA or who are unable to tolerate it. Although evidence for biochemical improvement by OCA is compelling, there is, as yet, no evidence that OCA improves hard clinical outcomes or quality of life. In addition, OCA may not be suitable for PBC patients with pruritus as it can worsen the symptom. Other novel agents currently in clinical development may have better side-effect profile. Fibrates have the potential but currently lack high quality evidence to support their routine clinical use in PBC. Symptom management of PBC is challenging and ASBT inhibitors and rituximab are being evaluated for pruritus and fatigue, respectively. © 2017 S. Karger AG, Basel.
Recent advances in the diagnosis and treatment of primary biliary cholangitis
Huang, Ying-Qiu
2016-01-01
Primary biliary cholangitis (PBC), formerly referred to as primary biliary cirrhosis, is an infrequent progressive intrahepatic cholestatic autoimmune illness that can evolve into hepatic fibrosis, hepatic cirrhosis, hepatic failure, and, in some cases, hepatocellular carcinoma. The disease itself is characterized by T-lymphocyte-mediated chronic non-suppurative destructive cholangitis and elevated serum levels of extremely specific anti-mitochondrial autoantibodies (AMAs). In this article, we will not only review epidemiology, risk factors, natural history, predictive scores, radiologic approaches (e.g., acoustic radiation force impulse imaging, vibration controlled transient elastography, and magnetic resonance elastography), clinical features, serological characteristics covering biochemical markers, immunoglobulins, infections markers, biomarkers, predictive fibrosis marker, specific antibodies (including AMAs such as AMA-M2), anti-nuclear autoantibodies [such as anti-multiple nuclear dot autoantibodies (anti-sp100, PML, NDP52, anti-sp140), anti-rim-like/membranous anti-nuclear autoantibodies (anti-gp210, anti-p62), anti-centromere autoantibodies, and some of the novel autoantibodies], histopathological characteristics of PBC, diagnostic advances, and anti-diastole of PBC. Furthermore, this review emphasizes the recent advances in research of PBC in terms of therapies, including ursodeoxycholic acid, budesonide, methotrexate, obeticholic acid, cyclosporine A, fibrates such as bezafibrate and fenofibrate, rituximab, mesenchymal stem cells transplant, and hepatic transplant. Currently, hepatic transplant remains the only optimal choice with acknowledged treatment efficiency for end-stage PBC patients. PMID:27957241
Body Consciousness, Illness-Related Impairment, and Patient Adherence in Hemodialysis.
ERIC Educational Resources Information Center
Christensen, Alan J.; And Others
1996-01-01
Examined the joint effects of private body consciousness (PBC) and degree of illness-related physical impairment on treatment regimen adherence in a sample of 52 hemodialysis patients. Predicted the effect of PBC on adherence would vary as a function of patients' level of illness-related physical impairment. Results are discussed in terms of…
High-power laser diodes with high polarization purity
NASA Astrophysics Data System (ADS)
Rosenkrantz, Etai; Yanson, Dan; Peleg, Ophir; Blonder, Moshe; Rappaport, Noam; Klumel, Genady
2017-02-01
Fiber-coupled laser diode modules employ power scaling of single emitters for fiber laser pumping. To this end, techniques such as geometrical, spectral and polarization beam combining (PBC) are used. For PBC, linear polarization with high degree of purity is important, as any non-perfectly polarized light leads to losses and heating. Furthermore, PBC is typically performed in a collimated portion of the beams, which also cancels the angular dependence of the PBC element, e.g., beam-splitter. However, we discovered that single emitters have variable degrees of polarization, which depends both on the operating current and far-field divergence. We present data to show angle-resolved polarization measurements that correlate with the ignition of high-order modes in the slow-axis emission of the emitter. We demonstrate that the ultimate laser brightness includes not only the standard parameters such as power, emitting area and beam divergence, but also the degree of polarization (DoP), which is a strong function of the latter. Improved slow-axis divergence, therefore, contributes not only to high brightness but also high beam combining efficiency through polarization.
Mullan, Barbara; Wong, Cara; Kothe, Emily
2013-03-01
The aim of this study was to investigate whether the theory of planned behaviour (TPB) with the addition of risk awareness could predict breakfast consumption in a sample of adolescents from the UK and Australia. It was hypothesised that the TPB variables of attitudes, subjective norm and perceived behavioural control (PBC) would significantly predict intentions, and that inclusion of risk perception would increase the proportion of variance explained. Secondly it was hypothesised that intention and PBC would predict behaviour. Participants were recruited from secondary schools in Australia and the UK. A total of 613 participants completed the study (448 females, 165 males; mean=14years ±1.1). The TPB predicted 42.2% of the variance in intentions to eat breakfast. All variables significantly predicted intention with PBC as the strongest component. The addition of risk made a small but significant contribution to the prediction of intention. Together intention and PBC predicted 57.8% of the variance in breakfast consumption. Copyright © 2012 Elsevier Ltd. All rights reserved.
The relationship between liver histology and noninvasive markers in primary biliary cirrhosis.
Olmez, Sehmus; Sayar, Suleyman; Avcioglu, Ufuk; Tenlik, İlyas; Ozaslan, Ersan; Koseoglu, Hasan T; Altiparmak, Emin
2016-07-01
Primary biliary cirrhosis (PBC) is a disease that affects liver with various severity and progression rates. It is important to diagnose advanced stage of the disease to lower liver-related morbidity and mortality. Since liver biopsy is an invasive method, liver biopsy tends to be replaced by noninvasive methods. In this study, we aim to show the role of aminotransferase to platelet ratio index (APRI) and fibrosis index on the basis of the four factors (FIB-4) scores, laboratory values, and their effectiveness in predicting advanced disease. PBC patients diagnosed pathologically at Numune Education and Research Hospital were included in the study between the years 1995 and 2013. Patients were grouped according to their fibrosis level: group 1 (early stage) included 18 patients with F1 and F2 fibrosis and group 2 (advanced stage) included 22 patients with F3 and F4 fibrosis. APRI and FIB-4 scores, routine laboratory values, and their proportions were compared. The effectiveness of parameters showing advanced stage was further compared. There were statistically significant differences in APRI, FIB-4 scores, and aspartate aminotransferase (AST) levels between the groups with early and advanced stages of disease. Receiver operating curve analysis was used to determine APRI, FIB-4 and AST levels. The most effective parameters for diagnosing an advanced stage were APRI, AST levels, and FIB-4 scores, respectively. In conclusion, APRI and FIB-4 scores can be calculated simply and easily by routine laboratory tests at low cost and also these scores may be a predictor of advanced stage of the disease in PBC. These tests may be reproducible and may be used to monitor disease progression.
Kraft, Pål; Rise, Jostein; Sutton, Stephen; Røysamb, Espen
2005-09-01
A study was conducted to explore (a) the dimensional structure of perceived behavioural control (PBC), (b) the conceptual basis of perceived difficulty items, and (c) how PBC components and instrumental and affective attitudes, respectively, relate to intention and behaviour. The material stemmed from a two-wave study of Norwegian graduate students (N = 227 for the prediction of intention and N = 110 for the prediction of behaviour). Data were analysed using confirmatory factor analysis (CFA) and multiple regression by the application of structural equation modelling (SEM). CFA suggested that PBC could be conceived of as consisting of three separate but interrelated factors (perceived control, perceived confidence and perceived difficulty), or as two separate but interrelated factors representing self-efficacy (measured by perceived difficulty and perceived confidence or by just perceived confidence) and perceived control. However, the perceived difficulty items also overlapped substantially with affective attitude. Perceived confidence was a strong predictor of exercise intention but not of recycling intention. Perceived control, however, was a strong predictor of recycling intention but not exercise intention. Affective attitudes but not instrumental attitudes were identified as substantial predictors of intentions. The findings suggest that at least under some circumstances it may be inadequate to measure PBC by means of perceived difficulty. One possible consequence may be that the role of PBC as a predictor of intention is somewhat overestimated, whereas the role of (affective) attitude may be similarly underestimated.
Five-year risk of interval-invasive second breast cancer.
Lee, Janie M; Buist, Diana S M; Houssami, Nehmat; Dowling, Emily C; Halpern, Elkan F; Gazelle, G Scott; Lehman, Constance D; Henderson, Louise M; Hubbard, Rebecca A
2015-07-01
Earlier detection of second breast cancers after primary breast cancer (PBC) treatment improves survival, yet mammography is less accurate in women with prior breast cancer. The purpose of this study was to examine women presenting clinically with second breast cancers after negative surveillance mammography (interval cancers), and to estimate the five-year risk of interval-invasive second cancers for women with varying risk profiles. We evaluated a prospective cohort of 15 114 women with 47 717 surveillance mammograms diagnosed with stage 0-II unilateral PBC from 1996 through 2008 at facilities in the Breast Cancer Surveillance Consortium. We used discrete time survival models to estimate the association between odds of an interval-invasive second breast cancer and candidate predictors, including demographic, PBC, and imaging characteristics. All statistical tests were two-sided. The cumulative incidence of second breast cancers after five years was 54.4 per 1000 women, with 325 surveillance-detected and 138 interval-invasive second breast cancers. The five-year risk of interval-invasive second cancer for women with referent category characteristics was 0.60%. For women with the most and least favorable profiles, the five-year risk ranged from 0.07% to 6.11%. Multivariable modeling identified grade II PBC (odds ratio [OR] = 1.95, 95% confidence interval [CI] = 1.15 to 3.31), treatment with lumpectomy without radiation (OR = 3.27, 95% CI = 1.91 to 5.62), interval PBC presentation (OR = 2.01, 95% CI 1.28 to 3.16), and heterogeneously dense breasts on mammography (OR = 1.54, 95% CI = 1.01 to 2.36) as independent predictors of interval-invasive second breast cancers. PBC diagnosis and treatment characteristics contribute to variation in subsequent-interval second breast cancer risk. Consideration of these factors may be useful in developing tailored post-treatment imaging surveillance plans. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Five-Year Risk of Interval-Invasive Second Breast Cancer
Buist, Diana S. M.; Houssami, Nehmat; Dowling, Emily C.; Halpern, Elkan F.; Gazelle, G. Scott; Lehman, Constance D.; Henderson, Louise M.; Hubbard, Rebecca A.
2015-01-01
Background: Earlier detection of second breast cancers after primary breast cancer (PBC) treatment improves survival, yet mammography is less accurate in women with prior breast cancer. The purpose of this study was to examine women presenting clinically with second breast cancers after negative surveillance mammography (interval cancers), and to estimate the five-year risk of interval-invasive second cancers for women with varying risk profiles. Methods: We evaluated a prospective cohort of 15 114 women with 47 717 surveillance mammograms diagnosed with stage 0-II unilateral PBC from 1996 through 2008 at facilities in the Breast Cancer Surveillance Consortium. We used discrete time survival models to estimate the association between odds of an interval-invasive second breast cancer and candidate predictors, including demographic, PBC, and imaging characteristics. All statistical tests were two-sided. Results: The cumulative incidence of second breast cancers after five years was 54.4 per 1000 women, with 325 surveillance-detected and 138 interval-invasive second breast cancers. The five-year risk of interval-invasive second cancer for women with referent category characteristics was 0.60%. For women with the most and least favorable profiles, the five-year risk ranged from 0.07% to 6.11%. Multivariable modeling identified grade II PBC (odds ratio [OR] = 1.95, 95% confidence interval [CI] = 1.15 to 3.31), treatment with lumpectomy without radiation (OR = 3.27, 95% CI = 1.91 to 5.62), interval PBC presentation (OR = 2.01, 95% CI 1.28 to 3.16), and heterogeneously dense breasts on mammography (OR = 1.54, 95% CI = 1.01 to 2.36) as independent predictors of interval-invasive second breast cancers. Conclusions: PBC diagnosis and treatment characteristics contribute to variation in subsequent-interval second breast cancer risk. Consideration of these factors may be useful in developing tailored post-treatment imaging surveillance plans. PMID:25904721
Xu, Chao; Chen, Hao-Xiang; Xiang, Qian; Zhu, Han-Hua; Wang, Shuai; Zhu, Qi-Hong; Huang, Dao-You; Zhang, Yang-Zhu
2018-01-01
Soil amendments, such as biochar, have been used to enhance the immobilization of heavy metals in contaminated soil. A pot experiment was conducted to immobilize the available cadmium (Cd) and lead (Pb) in soil using peanut shell biochar (PBC) and wheat straw biochar (WBC), and to observe the accumulation of these heavy metals in rice (Oryza sativa L.). The application of PBC and WBC led to significantly higher pH, soil organic carbon (SOC), and cation exchange capacity (CEC) in paddy soil, while the content of MgCl 2 -extractable Cd and Pb was lower than that of untreated soil. MgCl 2 -extractable Cd and Pb showed significant negative correlations with pH, SOC, and CEC (p < 0.01). The application of 5% biochar to contaminated paddy soil led to reductions of 40.4-45.7 and 68.6-79.0%, respectively, in the content of MgCl 2 -extractable Cd and Pb. PBC more effectively immobilized Cd and Pb than WBC. Sequential chemical extractions revealed that biochar induced the transformation of the acid-soluble fraction of Cd to oxidizable and residual fractions, and the acid-soluble fraction of Pb to reducible and residual fractions. PBC and WBC clearly inhibited the uptake and accumulation of Cd and Pb in rice plants. Specially, when compared to the corresponding concentrations in rice grown in control soils, 5% PBC addition lowered Cd and Pb concentrations in grains by 22.9 and 12.2%, respectively, while WBC addition lowered them by 29.1 and 15.0%, respectively. Compared to Pb content, Cd content was reduced to a greater extent in grain by PBC and WBC. These results suggest that biochar application is effective for immobilizing Cd and Pb in contaminated paddy soil, and reduces their bioavailability in rice. Biochar could be used as a soil amendment for the remediation of soils contaminated with heavy metals.
Khanna, Amardeep; Jopson, Laura; Howel, Denise; Bryant, Andrew; Blamire, Andrew; Newton, Julia L; Jones, David E
2018-05-23
Primary Biliary Cholangitis (PBC) is a chronic cholestatic liver disease. Half of patients experience debilitating fatigue which is currently untreatable. Previous studies have shown muscle bioenergetic abnormalities in PBC, including increased muscle acidosis with exercise linked to the anti-mitochondrial antibody (AMA) diagnostic of the disease, and reduced anaerobic threshold. In this study we addressed the hypothesis that fatigue in PBC is driven by muscle bioenergetic abnormality related to AMA, and that AMA reduction with B-cell depletion therapy will improve fatigue. In our single-centred Phase II randomised controlled trial (RCT) 57 participants aged ≥18 years with PBC and moderate or severe fatigue were randomized to receive 2 doses of either rituximab (1000mg) or saline (placebo). The primary outcome measure was fatigue severity assessed using the PBC-40 fatigue domain at 3 months. Secondary outcomes measures included patient-reported outcomes, immunological and bioenergetics disease parameters. Experimental outcomes included biochemical markers of disease severity. Improvement in fatigue score at 3 months was seen in both arms, with no significant difference (adjusted mean difference -0.9 95%CI -4.6 to 3.1). Little difference was observed in other patient reported outcomes or physical activity. Significant anaerobic threshold improvement was seen in the Rituximab group only but this was not associated with fatigue improvement. No treatment-emergent SAEs were seen. Rituximab was safe over the 12 month study period but showed no evidence of effectiveness for the treatment of fatigue in PBC. Anaerobic threshold improvement was seen; potentially linking AMA with muscle bioenergetics dysfunction, however, this was not related to improvement in fatigue. Rituximab had some evidence of a beneficial effect on alkaline phosphatase levels in this largely UDCA-responding, early disease stage cohort. This article is protected by copyright. All rights reserved. © 2018 by the American Association for the Study of Liver Diseases.
Cheung, Ka-Shing; Seto, Wai-Kay; Fung, James; Lai, Ching-Lung; Yuen, Man-Fung
2017-08-31
Studies on the epidemiology of primary biliary cholangitis (PBC) in the Chinese population are lacking. We aimed to determine the epidemiology of PBC in Hong Kong (HK) with a population of 7.3 million. We retrieved data from the electronic database of the HK Hospital Authority, the only public healthcare provider in Hong Kong. PBC cases between 2000 and 2015 were identified by International Classification of Diseases (ICD)-9 code. We estimated the age-/sex-adjusted incidence rate and prevalence of PBC, and analyzed the adverse outcomes (hepatocellular carcinoma (HCC), liver transplantation, and death). One thousand and sixteen PBC patients aged ≥20 years were identified (female-to-male ratio 4:1; median age 60.6 years, interquartile range (IQR) 51.8-72.6 years; median follow-up 5.6 years, IQR 1.6-8.7 years). The average age/sex-adjusted annual incidence rate and prevalence were 8.4 per million person-years and 56.4 per million, respectively. Between 2000 and 2015, the age/sex-adjusted annual incidence rate increased from 6.7 to 8.1 per million person-years (Poisson P=0.002), while age/sex-adjusted prevalence increased from 31.1 to 82.3 per million (Poisson P<0.001). Fifty patients developed HCC, and 49 underwent liver transplantation. Case fatality risk decreased from 10.8 to 6.4% (Poisson P=0.003). The 5- and 10-year overall survival rates were 81.5 and 78.3%, whereas the transplant-free survival rates were 78.0% and 74.3%, respectively. Increasing age, cirrhosis and being treatment-naïve were associated with lower transplant-free survival. There is a considerable increase in the incidence and prevalence of PBC in the Chinese population over the past 16 years, with significant morbidity and mortality.
2013-01-01
Background Transitioning to parenthood is a major life event that may impact parents’ personal lifestyles, yet there is an absence of theory-based research examining the impact of parenthood on motives for dietary behaviour. As a result, we are unaware of the social cognitive variables that predict eating behaviour among those transitioning to parenthood. The purpose of the study was to examine eating behaviour motives across 12 months within the framework of the theory of planned behavior (TPB) and compare these across groups of new parents, non-parents, and established parents. Methods Non-parents (n = 92), new parents (n = 135), and established parents (n = 71) completed TPB questionnaires assessing attitudes, subjective norms, perceived behavioral control (PBC), and intentions and three day food records at baseline, and 6- and 12-months post-delivery (for parents) and 6- and 12-months post-baseline (for non-parents). Results Repeated measures ANOVAs revealed that among men, new- and established-parents had greater intentions to eat healthy compared to non-parents, F(2) = 3.59, p = .03. Among women, established parents had greater intentions than new- and non-parents, F(2) = 5.33, p = .01. Among both men and women during the first 6-months post-delivery, new-parents experienced decreased PBC, whereas established parents experienced increased PBC. Overall, affective attitudes were the strongest predictor of intentions for men (β = 0.55, p < .001) and women (β = 0.38, p < .01). PBC predicted changes in fruit and vegetable consumption for men (β = 0.45, p = .02), and changes in fat consumption for men (β = −0.25, p = .03) and women (β = −.24, p < .05), regardless of parent status. Conclusion The transition to parenthood for new and established parents may impact motivation for healthy eating, especially PBC within the framework of TPB. However, regardless of parental status, affective attitudes and PBC are critical antecedents of intentions and eating behaviour. Interventions should target affective attitudes and PBC to motivate healthy eating and may need to be intensified during parenthood. PMID:23829582
Smith, Susan M.; Pegram, Angela H.
2017-01-01
Objective: To review the pharmacology, efficacy, and safety of obeticholic acid (OCA) and determine its clinical role relative to other agents in the treatment of patients with primary biliary cholangitis (PBC). Data Sources: A PubMed search (1946 to November 2016) was conducted using the terms INT-747, obeticholic acid, OCA, farnesoid X receptor agonists, FXR agonists, primary biliary cirrhosis, and primary biliary cholangitis. Study Selection and Data Extraction: Phase II and III studies evaluating the use of OCA in PBC patients were included in this review. Data Synthesis: OCA, a farnesoid X receptor (FXR) agonist, is indicated for adult patients with PBC in combination with ursodeoxycholic acid (UDCA) or as monotherapy if unable to tolerate UDCA. Two clinical trials were identified evaluating OCA for the treatment of PBC. Study end points utilized biochemical markers (alkaline phosphatase [ALP] and bilirubin). A phase II study (n = 165) to determine efficacy and safety of OCA at 3 different doses (10 mg, 25 mg, 50 mg) demonstrated statistically significant reductions in ALP (P < .0001 for all OCA groups versus placebo) after 12 weeks. A phase III trial (n = 217) assessed lower OCA doses (5 mg and 10 mg) with a longer study duration (12 months). Statistically significant differences (P < .001) between the 5 to 10 mg group (46%) and the 10 mg group (47%) compared to the placebo group (10%) were found. The primary adverse effect reported in both trials was pruritus. Conclusions: OCA is the first FXR agonist approved for the treatment of PBC. Ongoing research to evaluate clinical outcomes with OCA is currently underway.
Berg, Christoph P; Stein, Gerburg M; Klein, Reinhild; Pascu, Maria; Berg, Thomas; Kammer, Winfried; Priemer, Martin; Nordheim, Alfred; Schulze-Osthoff, Klaus; Gregor, Michael; Wesselborg, Sebastian; Berg, Peter A
2006-09-01
Primary biliary cirrhosis (PBC) is characterized by the presence of antimitochondrial antibodies (AMA). Autoantibodies specific for the mitochondrial M4 antigen can be detected by a complement fixation test (CFT) but not by immunoblotting. The aim of this study was to elucidate the identity of the M4 antigen. M4 proteins were purified by affinity chromatography using IgG fractions of PBC marker sera being CFT positive (n=5) or negative (n=5) and identified by Western blotting, silver staining and sequence analysis. Further, a cohort of 57 PBC patients was tested for the reactivity to M4 and pyruvate dehydrogenase complex (PDC). Two AMA patterns of the marker sera were visualized: CFT-positive sera were defined as PDC-E2(+)/E1(+) and the CFT-negative sera as PDC-E2(+)/E1(-). The major proteins in the M4 fraction could be related to the PDC-E1 subunits. A clear-cut association between anti-M4 reactivity in the CFT and the reactivity to both PDC subunits could also be documented in the cohort of 57 PBC patients showing anti-PDC-E1alpha and E1beta antibodies at a frequency of 74% and 67%. CFT reactivity against M4 antigens could be preferentially identified as a reaction against PDC-E1. As PDC-E1 subunits as compared with PDC-E2 lack lipoyl-binding sites, they probably have to be considered as an independent and important target.
Cost and health consequences of treatment of primary biliary cirrhosis with ursodeoxycholic acid.
Boberg, K M; Wisløff, T; Kjøllesdal, K S; Støvring, H; Kristiansen, I S
2013-10-01
Long-term use of ursodeoxycholic acid (UDCA) is the recommended therapy in primary biliary cirrhosis (PBC). The lifetime effectiveness and cost-effectiveness of UDCA in PBC have, however, not been assessed. To estimate the health outcomes and lifetime costs of a Norwegian cohort of PBC patients on UDCA. Norwegian PBC patients (n = 182) (90% females; mean age 56.3 ± 8.9 years; Mayo risk score 4.38) who were included in a 5-year open-label study of UDCA therapy were subsequently followed up for up to 11.5 years. The lifetime survival was estimated using a Weibull survival model. The survival benefit from UDCA was based on a randomised clinical trial from Canada, comparing the effect of non-UDCA and UDCA. Survival and costs of standard care vs. standard care plus UDCA were simulated in a Markov model with death and liver transplantation as major events, invoking transition of a patient's state in the model. The gain in life expectancy for a PBC patient on UDCA compared with standard care was 2.24 years (1.19 years discounted). The lifetime treatment costs were EUR 151,403 and EUR 157,741 (EUR 102,912 and EUR 115,031 discounted) for patients with and without UDCA respectively. A probabilistic sensitivity analysis indicated an 82% probability that UDCA entails both greater life expectancy and lower costs than standard care. The results of this study indicate that UDCA therapy is a dominant strategy as it confers reduced morbidity and mortality, as well as cost savings, compared with standard therapy. © 2013 John Wiley & Sons Ltd.
Kita, Hiroto; Matsumura, Shuji; He, Xiao-Song; Ansari, Aftab A.; Lian, Zhe-Xiong; Van de Water, Judy; Coppel, Ross L.; Kaplan, Marshall M.; Gershwin, M. Eric
2002-01-01
While the pathologic mechanisms responsible for organ-specific tissue damage in primary biliary cirrhosis (PBC) remain an enigma, it has been suggested that the pathology is mediated by autoreactive T cells infiltrating the intrahepatic bile ducts. Previously, we have documented that there is 100-fold enrichment in the frequency of CD4+ autoreactive T cells in the liver that are specific for peptides encoded by the E2 components of the pyruvate dehydrogenase complexes (PDC-E2). We have also recently characterized the first MHC class I–restricted epitope for PDC-E2, namely amino acid 159–167, a region very similar to the epitope recognized by MHC class II–restricted CD4+ cells and by autoantibodies. The effector functions of these PDC-E2159-167–specific CD8+ cytotoxic T lymphocytes (CTLs) are not well understood. We have taken advantage of tetramer technology and report herein that there is tenfold increase in the frequency of PDC-E2159-167–specific CTLs in the liver as compared with the blood in PBC. In addition, the precursor frequency of the CTLs in blood was significantly higher in early-stage PBC. Of interest was the fact that, upon stimulation with the peptide, the response of PDC-E2159-167 tetramer-positive cells is heterogeneous with respect to IFN-γ synthesis. These data, we believe for the first time, document the enrichment of autoantigen-specific CD8+ T cells in the PBC liver, suggesting that CD8+ T cells play a significant role in the immunopathogenesis of PBC. PMID:11994412
USDA-ARS?s Scientific Manuscript database
New poly-phenolic branched-chain fatty acid (poly-PBC-FA) products were synthesized from a combination of soybean fatty acids and phenolic materials through a highly efficient zeolite catalyzed arylation method. These poly-PBC-FAs are liquid at room temperature and do not have the unpleasant odor li...
Muratori, Paolo; Efe, Cumali; Muratori, Luigi; Ozaslan, Ersan; Schiano, Thomas; Yoshida, Eric M; Heurgué-Berlot, Alexandra; Lalanne, Claudine; Lenzi, Marco; Wahlin, Staffan
2017-07-01
Antimitochondrial antibody (AMA) positivity is the serological marker of primary biliary cholangitis (PBC), but can also be sporadically detected in autoimmune hepatitis (AIH). Little is known about the clinical significance of AMA in AIH. We recruited 47 AMA-positive AIH cases from several centres and compared them with 264 well-characterized Italian AIH patients. Cases with any features of PBC were excluded. In univariate analysis, AMA-positive AIH patients were older (46 vs. 36, P=0.002) and more responsive to immunosuppression (74 vs. 59%, P=0.05), but no differences were observed between the two groups after logistic regression using AMA as a dependent variable. None of the AMA-positive AIH patients showed signs of evolving PBC features after a median follow-up of up 47 months. AMA was detected in combination with all serological AIH markers except antiliver kidney microsome type 1 and antiliver cytosol type 1. AMA was the only marker of autoimmunity in eight cases. We found no differences between AIH with and without AMA. The groups had similar clinical, biochemical and histological features. AMA-positive AIH patients did not evolve towards PBC. In some cases, AMA was the only autoantibody.
Marine Ecological Risk Assessment Pilot Study for Allen Harbor, Narragansett Bay, Rhode Island
1992-01-01
evidence of major contamination in sediments or tissues except for relatively high levels of polychlorinated biphenols (PBC), butyltins compounds ( TBT ...biphenols (PBC), butyltin compounds ( TBT ), and fecal coliforms observed in Allen Harbor. Effects were detected in mussel physiology, sea urchin fertilization...Dichiorodiphenyl- dichioroethene HBC - Hexachlorobenzene TBT -Thbutyltin METALS Cu - Copper Zn -Zinc Cr - Chromium Pb -Lead Ni - Nickel As - Arsenic
Electrophile-modified lipoic derivatives of PDC-E2 elicits anti-mitochondrial antibody reactivity.
Naiyanetr, Phornnop; Butler, Jeffrey D; Meng, Liping; Pfeiff, Janice; Kenny, Thomas P; Guggenheim, Kathryn G; Reiger, Roman; Lam, Kit; Kurth, Mark J; Ansari, Aftab A; Coppel, Ross L; López-Hoyos, Marcos; Gershwin, M Eric; Leung, Patrick S C
2011-11-01
Our laboratory has hypothesized that xenobiotic modification of the native lipoyl moiety of the major mitochondrial autoantigen, the E2 subunit of the pyruvate dehydrogenase complex (PDC-E2), may lead to loss of self-tolerance in primary biliary cirrhosis (PBC). This thesis is based on the finding of readily detectable levels of immunoreactivity of PBC sera against extensive panels of protein microarrays containing mimics of the inner lipoyl domain of PDC-E2 and subsequent quantitative structure-activity relationships (QSARs). Importantly, we have demonstrated that murine immunization with one such mimic, 2-octynoic acid coupled to bovine serum albumin (BSA), induces anti-mitochondrial antibodies (AMAs) and cholangitis. Based upon these data, we have focused on covalent modifications of the lipoic acid disulfide ring and subsequent analysis of such xenobiotics coupled to a 15mer of PDC-E2 for immunoreactivity against a broad panel of sera from patients with PBC and controls. Our results demonstrate that AMA-positive PBC sera demonstrate marked reactivity against 6,8-bis(acetylthio)octanoic acid, implying that chemical modification of the lipoyl ring, i.e. disruption of the S-S disulfide, renders lipoic acid to its reduced form that will promote xenobiotic modification. This observation is particularly significant in light of the function of the lipoyl moiety in electron transport of which the catalytic disulfide constantly opens and closes and, thus, raises the intriguing thesis that common electrophilic agents, i.e. acetaminophen or non-steroidal anti-inflammatory drugs (NSAIDs), may lead to xenobiotic modification in genetically susceptible individuals that results in the generation of AMAs and ultimately clinical PBC. Copyright © 2011 Elsevier Ltd. All rights reserved.
Tarai, B; Das, P; Kumar, D; Budhiraja, S
2012-01-01
Paired blood culture (PBC) is uncommon practice in hospitals in India, leading to delayed and inadequate diagnosis. Also contamination remains a critical determinant in hampering the definitive diagnosis. To establish the need of PBC over single blood culture (SBC) along with the degree of contamination, this comparative retrospective study was initiated. We processed 2553 PBC and 4350 SBC in BacT/ALERT 3D (bioMerieux) between October 2010 and June 2011. The positive cultures were identified in VITEK 2 Compact (bioMerieux). True positivity and contaminants were also analyzed in 486 samples received from catheter and peripheral line. Out of 2553 PBC samples, positivity was seen in 350 (13.70%). In 4350 SBC samples, positivity was seen in 200 samples (4.59%). In PBC true pathogens were 267 (10.45%) and contaminants were 83 (3.25%), whereas in SBC 153 (3.51%) were true positives and contaminants were 47 (1.08%). Most of the blood cultures (99.27 %) grew within 72 h and 95.8% were isolated within 48 h. In 486 PBCs received from catheter/periphery (one each), catheter positivity was found in 85 (true positives were 48, false positives 37). In peripheral samples true positives were 50 and false positives were 8. Significantly higher positive rates were seen in PBCs compared with SBCs. Automated blood culture and identification methods significantly reduced the time required for processing of samples and also facilitated yield of diverse/rare organisms. Blood culture from catheter line had higher false positives than peripheral blood culture. Thus every positive result from a catheter must be correlated with clinical findings and requires further confirmation.
Molecular diagnostic testing for primary biliary cholangitis.
Gatselis, Nikolaos K; Dalekos, George N
2016-09-01
A reliable liver autoimmune serology for the diagnosis of primary biliary cholangitis (PBC) is of particular importance. Recognition of patients at early stages and prompt treatment initiation may alter the outcome, slow progression, delays liver failure, and improves survival. In this review, we summarize and discuss the published data obtained from literature searches from PubMed and The National Library of Medicine (USA) and our own experience on the current and potential molecular based approaches to the diagnosis of PBC. Expert commentary: Standardization of liver diagnostic serology and clinical governance are two major points as antimitochondrial antibodies are the diagnostic hallmark of the disease and PBC-specific antinuclear antibodies could assist in the diagnosis and estimation of prognosis. New biomarkers such as novel autoantibodies, genetic polymorphisms, metabolomic profiling, micro-RNA and epigenetics may assist to the understanding, diagnosis and management of the disease.
Karimi, Saeid; Biemans, Harm J A; Naderi Mahdei, Karim; Lans, Thomas; Chizari, Mohammad; Mulder, Martin
2017-06-01
Drawing upon the theory of planned behaviour (TPB), we developed and tested a conceptual model which integrates both internal personality factors and external contextual factors to determine their associations with motivational factors and entrepreneurial intentions (EIs). We then investigated if the model of EI applies in a developing country, namely Iran. We also set out to identify the most relevant factors for EI within this developing country context. Do distal predictors of EI including personality factors (i.e. need for achievement, risk taking and locus of control) and contextual factors (i.e. perceived barriers and support) significantly relate to EI via proximal predictors including motivational factors (i.e. attitudes towards entrepreneurship and perceived behavioural control [PBC])? Data were collected on 331 students from 7 public universities. The findings support the TPB for EI in Iran. All three motivational factors related to EI, but PBC showed the strongest association, which is different than in developed country contexts. Possible explanations for these differences are discussed. All three personality characteristics indirectly related to EI via the proximal attitudes towards entrepreneurship and PBC. Perceived contextual support and barriers indirectly related to EI via proximal PBC while perceived barriers also directly related to EI. © 2015 International Union of Psychological Science.
Karayannis, Nicholas V; Jull, Gwendolen A; Hodges, Paul W
2012-02-20
Several classification schemes, each with its own philosophy and categorizing method, subgroup low back pain (LBP) patients with the intent to guide treatment. Physiotherapy derived schemes usually have a movement impairment focus, but the extent to which other biological, psychological, and social factors of pain are encompassed requires exploration. Furthermore, within the prevailing 'biological' domain, the overlap of subgrouping strategies within the orthopaedic examination remains unexplored. The aim of this study was "to review and clarify through developer/expert survey, the theoretical basis and content of physical movement classification schemes, determine their relative reliability and similarities/differences, and to consider the extent of incorporation of the bio-psycho-social framework within the schemes". A database search for relevant articles related to LBP and subgrouping or classification was conducted. Five dominant movement-based schemes were identified: Mechanical Diagnosis and Treatment (MDT), Treatment Based Classification (TBC), Pathoanatomic Based Classification (PBC), Movement System Impairment Classification (MSI), and O'Sullivan Classification System (OCS) schemes. Data were extracted and a survey sent to the classification scheme developers/experts to clarify operational criteria, reliability, decision-making, and converging/diverging elements between schemes. Survey results were integrated into the review and approval obtained for accuracy. Considerable diversity exists between schemes in how movement informs subgrouping and in the consideration of broader neurosensory, cognitive, emotional, and behavioural dimensions of LBP. Despite differences in assessment philosophy, a common element lies in their objective to identify a movement pattern related to a pain reduction strategy. Two dominant movement paradigms emerge: (i) loading strategies (MDT, TBC, PBC) aimed at eliciting a phenomenon of centralisation of symptoms; and (ii) modified movement strategies (MSI, OCS) targeted towards documenting the movement impairments associated with the pain state. Schemes vary on: the extent to which loading strategies are pursued; the assessment of movement dysfunction; and advocated treatment approaches. A biomechanical assessment predominates in the majority of schemes (MDT, PBC, MSI), certain psychosocial aspects (fear-avoidance) are considered in the TBC scheme, certain neurophysiologic (central versus peripherally mediated pain states) and psychosocial (cognitive and behavioural) aspects are considered in the OCS scheme.
Evaluation of six TPS algorithms in computing entrance and exit doses
Metwaly, Mohamed; Glegg, Martin; Baggarley, Shaun P.; Elliott, Alex
2014-01-01
Entrance and exit doses are commonly measured in in vivo dosimetry for comparison with expected values, usually generated by the treatment planning system (TPS), to verify accuracy of treatment delivery. This report aims to evaluate the accuracy of six TPS algorithms in computing entrance and exit doses for a 6 MV beam. The algorithms tested were: pencil beam convolution (Eclipse PBC), analytical anisotropic algorithm (Eclipse AAA), AcurosXB (Eclipse AXB), FFT convolution (XiO Convolution), multigrid superposition (XiO Superposition), and Monte Carlo photon (Monaco MC). Measurements with ionization chamber (IC) and diode detector in water phantoms were used as a reference. Comparisons were done in terms of central axis point dose, 1D relative profiles, and 2D absolute gamma analysis. Entrance doses computed by all TPS algorithms agreed to within 2% of the measured values. Exit doses computed by XiO Convolution, XiO Superposition, Eclipse AXB, and Monaco MC agreed with the IC measured doses to within 2%‐3%. Meanwhile, Eclipse PBC and Eclipse AAA computed exit doses were higher than the IC measured doses by up to 5.3% and 4.8%, respectively. Both algorithms assume that full backscatter exists even at the exit level, leading to an overestimation of exit doses. Despite good agreements at the central axis for Eclipse AXB and Monaco MC, 1D relative comparisons showed profiles mismatched at depths beyond 11.5 cm. Overall, the 2D absolute gamma (3%/3 mm) pass rates were better for Monaco MC, while Eclipse AXB failed mostly at the outer 20% of the field area. The findings of this study serve as a useful baseline for the implementation of entrance and exit in vivo dosimetry in clinical departments utilizing any of these six common TPS algorithms for reference comparison. PACS numbers: 87.55.‐x, 87.55.D‐, 87.55.N‐, 87.53.Bn PMID:24892349
Primary care in an era of hospital bed reduction: what can we infer from QOF and PBC?
Checkland, Kath; Harrison, Stephen
2010-12-01
The Quality and Outcomes Framework (QOF) has been efficiently and effectively incorporated into practice routines. One possible negative effect of this has been a move towards a more biomedical form of practice.There has been patchy but real engagement with practice-based commissioning (PBC), with significant moves in some areas towards GPs acting collectively to improve services across the health economy, including engaging in performance management of each others' practice.Together, responses to QOF and PBC suggest that GPs may be willing and able to act both individually and collectively to try to mitigate the negative impacts of future spending reductions. General practice will be under a great deal of pressure in the next few years. Understanding the impact of past policy changes is essential if we are to ensure that the core values of general practice are maintained.
Dobbins, RL; O'Connor‐Semmes, RL; Young, MA
2016-01-01
A systems model was developed to describe the metabolism and disposition of ursodeoxycholic acid (UDCA) and its conjugates in healthy subjects based on pharmacokinetic (PK) data from published studies in order to study the distribution of oral UDCA and potential interactions influencing therapeutic effects upon interruption of its enterohepatic recirculation. The base model was empirically adapted to patients with primary biliary cirrhosis (PBC) based on current understanding of disease pathophysiology and clinical measurements. Simulations were performed for patients with PBC under two competing hypotheses: one for inhibition of ileal absorption of both UDCA and conjugates and the other only of conjugates. The simulations predicted distinctly different bile acid distribution patterns in plasma and bile. The UDCA model adapted to patients with PBC provides a platform to investigate a complex therapeutic drug interaction among UDCA, UDCA conjugates, and inhibition of ileal bile acid transport in this rare disease population. PMID:27537780
Martinez, Lourdes S.; Lewis, Nehama
2016-01-01
This study reports results from a large population-based survey of U.S. adults showing perceived behavioral control (PBC) moderations of associations between (1) attitude and intention, and (2) perceived norms and intention to engage in six health behaviors. Results are based on data collected from a nationally representative sample of U.S. adults ages 40-70 (N=2,489) and extend understanding of how behavioral theory can be used to guide the design and evaluation of health communication campaigns. OLS regression analyses show evidence for a significant positive PBC moderation of (1) attitude and intention, and (2) perceived norms and intention such that attitude or perceived norms toward the behavior is more strongly associated with behavioral intention among participants reporting higher levels of PBC. Implications for message design and the evaluation of communication campaigns are discussed. PMID:27565188
Fang, Yu-Qing; Lv, Dong-Xia; Jia, Wei; Li, Jun; Deng, Yong-Qiong; Wang, Yan; Yu, Min; Wang, Gui-Qiang
2014-10-01
To the best of our knowledge, this is the first study to address the use of glucocorticoids in the comparatively special population of pure primary biliary cirrhosis (PBC) patients who have high levels of immunoglobulin G (IgG) and transaminases but do not have PBC-autoimmune hepatitis overlap syndrome. Ursodeoxycholic acid (UDCA) is now assumed to be the standard therapy for PBC patients. However, patients treated with UDCA still have a risk of progression to cirrhosis and end-stage liver disease. The most recent European Association for the Study of the Liver guidelines of 2009 declared that further studies on glucocorticoid therapy in this disease should be a priority. Therefore, we designed this 3-year longitudinal retrospective study, which might provide deep insight into the treatment for PBC.The aim of this study was to assess whether the combination of prednisolone, UDCA, and azathioprine was superior to UDCA alone in these PBC patients.Sixty patients were enrolled in this study. Thirty-one patients underwent UDCA monotherapy, and 29 patients were treated with prednisolone, UDCA, and azathioprine. We analyzed their biochemistries, immune parameters, liver synthetic function, and noninvasive assessments of liver fibrosis, as well as treatment efficacy and adverse effects at baseline and at 1, 3, 6, 12, 24, and 36 months.Alkaline phosphatase (ALP), γ-glutamyl transpeptidase, alanine aminotransferase, and aspartate aminotransferase levels and the aspartate aminotransferase-to-platelet ratio index (APRI) and S-index improved dramatically in both groups, whereas IgG levels only decreased in the combination group (all P < 0.05). Albumin (ALB) levels decreased in the UDCA group but increased with the combination treatment at 36 months. Significant differences between the 2 groups were observed at 36 months in ALP (P = 0.005), IgG (P = 0.002), ALB (P = 0.002), APRI (P = 0.015), and S-index (P = 0.020). Prednisolone combined with UDCA and azathioprine showed a higher efficacy based on our new criteria.The combination of prednisolone, UDCA, and azathioprine is superior to UDCA alone for the treatment of pure PBC patients with high levels of IgG and transaminases. Side effects were minimal or absent.
Bellucci, Roberto; Oertelt, Sabine; Gallagher, Meagan; Li, Sigui; Zorn, Emmanuel; Weller, Edie; Porcheray, Fabrice; Alyea, Edwin P; Soiffer, Robert J; Munshi, Nikhil C; Gershwin, M Eric; Ritz, Jerome
2007-03-01
A unique characteristic of the autoimmune liver disease primary biliary cirrhosis (PBC) is the presence of high-titer and extremely specific autoantibodies to the E2 component of the pyruvate dehydrogenase complex (PDC-E2). Autoantibodies to PDC-E2 antigen have only been detected in patients with disease or in those who subsequently develop PBC. One exception has been a subgroup of patients with multiple myeloma (MM) who underwent allogeneic hematopoietic stem cell transplantation (HSCT) and received donor lymphocyte infusions (DLIs) after transplantation. These patients developed high-titer antibodies to a variety of myeloma-associated antigens, including PDC-E2, coincident with rejection of myeloma cells in vivo. To examine the specificity of autoantibodies to PDC in these patients, we screened sera from patients with MM, chronic leukemias, monoclonal gammopathy of unknown significance (MGUS), PBC, and healthy donors. Three of 11 patients with MM (27%) and 2 of 6 patients with chronic leukemias (33%) developed anti-PDC-E2 antibodies in association with DLI response; 2 of 12 (17%) patients in the MGUS pretreatment control population also had detectable anti-PDC responses. Interestingly, the epitope specificity of these PDC-E2 autoantibodies was distinctive, suggesting that the mechanisms leading to loss of tolerance in the transplantation patients are distinct from PBC.
Tavousi, Mahmoud; Montazeri, Ali; Hidarnia, Alireza; Hajizadeh, Ebrahim; Taremian, Farhad; Haerimehrizi, Aliasghar
2015-08-01
The theory of reasoned action (TRA) is one of the most common models in predicting health-related behaviors and is used more often in health education studies. This study aimed to add two control constructs (perceived behavioral control - PBC and self-efficacy - SE) to the TRA and compare them using the structural equation modeling (SEM) for substance use avoidance among Iranian male adolescents in order to find out which model was a better fit in predicting the intention. This was a cross-sectional study carried out in Tehran, Iran. Data were collected from a random sample of high school male students (15-19 years of age) using a questionnaire containing items related to the TRA plus items reflecting two additional constructs (SE and PBC). In all, 433 students completed the questionnaires. The results obtained from SEM indicated a better fit to the data for the TRA with SE compared to the TPB (TRA with PBC) and TRA (χ2/df=2.55, RMSEA=0.072, CFI=0.96, NFI=0.94, NNFI=0.95, SRMR=0.058). Comparing SE and PBC, the results showed that self-efficacy was a better control construct in improving the TRA and predicting substance use avoidance intention (41%). The TRA with SE had a better model fit than TPB and the original version of the TRA.
A decline of LAMP- 2 predicts ursodeoxycholic acid response in primary biliary cirrhosis
Wang, Lu; Guo, Guan-ya; Wang, Jing-bo; Zhou, Xin-min; Yang, Qiong; Han, Zhe-yi; Li, Qiang; Zhang, Jing-wen; Cai, Yun; Ren, Xiao-li; Zhou, Xia; Chen, Rui-rui; Shi, Yong-quan; Han, Ying; Fan, Dai-ming
2015-01-01
Biochemical response to ursodeoxycholic acid (UDCA) in patients with primary biliary cirrhosis (PBC) is variable. We have previously reported that augmented expression of lysosome-associated membrane protein 2 (LAMP-2) was correlated with the severity of PBC. This study aimed to determine whether serum LAMP-2 could serve as a predictor of biochemical response to UDCA. The efficiency of serum LAMP-2 to predict biochemical response was assessed after 1 year of UDCA treatment in PBC patients by a retrospective analysis. We found that the basal serum LAMP-2 level was increased in PBC, especially in patients with stage III-IV (p = 0.010) or TBIL > 1 mg/dL (p = 0.014). Baseline serum LAMP-2 was higher in non-responders than that in responders, but the difference was statistically insignificant. However, after UDCA treatment, serum LAMP-2 level decreased prominently in the first 3 months, which was more obvious in responders. Further studies showed that the 35% decline of LAMP-2 after treatment for 3 months could be stated as an indicator of UDCA response with the sensitivity of 62.9% and specificity of 75.0% by Paris criteria. Meanwhile the specificity and sensitivity were identified as 63.5% and 64.1% by Barcelona criteria. Together, a decline in LAMP-2 might help to predict the response to UDCA. PMID:25894308
Zhang, Hanyu; Wang, Zhaowei; Li, Ruining; Guo, Jialei; Li, Yan; Zhu, Junmin; Xie, Xiaoyun
2017-10-01
Heterogeneous photocatalysis namely titanium dioxide supported on reed straw biochar (acid pre-treated) (TiO 2 /pBC) was synthesized by sol-gel method. The morphology, surface area and structure of TiO 2 /pBC were characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), and X-ray diffraction (XRD). Low calcination condition maintained the structure of biochar completely and prevented the agglomeration of TiO 2 particles. Due to the combination of adsorption and photocatalysis, TiO 2 /pBC performed higher removal efficiency of sulfamethoxazole (SMX) than pure TiO 2 powder under UV light irradiation. The photocatalytic degradation (PCD) of SMX was also studied with the water collected from the Yellow River. Three high concentration inorganic anions (Cl - , NO 3 - , SO 4 2- ) of the river exerted certain degree of detrimental effects on the contaminant degradation. TiO 2 /pBC showed stable photocatalytic activity after five sequential PCD cycles. The biochar was able to promote further PCD on TiO 2 by adsorbing SMX and intermediates thereby prolonging the separation lifetime of electrons (e - ) and valence band hole (h + ). The transformation intermediates of SMX were identified and three possible degradation reactions of hydroxylation, opening of isoxazole ring and cleavage of SN bond might occur during the PCD of SMX. Copyright © 2017 Elsevier Ltd. All rights reserved.
Syu, Bi-Jhen; Loh, Chia-En; Hsueh, Yu-Hsin; Gershwin, M. Eric; Chuang, Ya-Hui
2016-01-01
Primary biliary cirrhosis (PBC) is a progressive autoimmune liver disease with a long natural history. The pathogenesis of PBC is thought to be orchestrated by Th1 and/or Th17. In this study, we investigated the role of CD4+ helper T subsets and their cytokines on PBC using our previous established murine model of 2-OA-OVA immunization. We prepared adeno-associated virus (AAV)-IFN-γ and AAV-IL-4 and studied their individual influences on the natural history of autoimmune cholangitis in this model. Administration of IFN-γ significantly promotes recruitment and lymphocyte activation in the earliest phases of autoimmune cholangitis but subsequently leads to downregulation of chronic inflammation through induction of the immunosuppressive molecule IL-30. In contrast, the administration of IL-4 does not alter the initiation of autoimmune cholangitis, but does contribute to the exacerbation of chronic liver inflammation and fibrosis. Thus Th1 cells and IFN-γ are the dominant contributors in the initiation phase of this model but clearly may have different effects as the disease progress. In conclusion, better understanding of the mechanisms by which helper T cells function in the natural history of cholangitis is essential and illustrates that precision medicine may be needed for patients with PBC at various stages of their disease process. PMID:27721424
Qi, Xiaole; Gao, Xiang; Lu, Zhen; Zhang, Lizhou; Wang, Yongqiang; Gao, Li; Gao, Yulong; Li, Kai; Gao, Honglei; Liu, Changjun; Cui, Hongyu; Zhang, Yanping; Wang, Xiaomei
2016-07-01
To test whether amino acid mutations in the PBC and PHI loops of VP2 are involved in the replication and virulence of infectious bursal disease virus (IBDV), a pair of viruses, namely the moderately virulent IBDV (rGx-F9VP2) and the attenuated strain (rGt), were used. Residue mutations A222P (PBC) and S330R (PHI), selected by sequence comparison, were introduced individually into rGx-F9VP2 by using a reverse genetics system. In addition, the reverse mutation of either P222A or R330S was introduced into rGt. The four modified viruses were then rescued and evaluated in vitro (CEF cells) and in vivo (SPF chickens). Results showed that A222P elevated the replication efficiency of rGx-F9VP2 while P222A reduced that of rGt in CEF cells. A mutation at residue 330 did not alter IBDV replication. In addition, animal experiments showed that a single mutation at either residue 222 or 330 did not significantly influence the virulence of IBDV. In conclusion, residue 222 in PBC of VP2 is involved in the replication efficiency of IBDV in vitro but does not affect its virulence in vivo, further facilitating our understanding of the gene-function of IBDV.
van Dam, G M; Gips, C H; Reisman, Y; Maas, K W; Purmer, I M; Huizenga, J R; Verbaan, B W
1999-01-01
One of the prognostic methods for survival in primary biliary cirrhosis (PBC) is the Mayo model, with a time-scale limited to 7 years. The aim of our study was to assess how major clinical events, signs, several severity assessment methods and Mayo survival probabilities fit in with actual patient survival, by using yearly observations until 0.5 years before patient death from PBC. Data of 32 patients dying from PBC were collected prior to death at -0.5, -1, -2 etc. years (median: -5 years, range: -16 to -0.5 years). Major events registered were: first occurrence of ascites, upper gastrointestinal bleeding or manifest hepatic encephalopathy and signs, first observation of spider naevi or purpura. Severity assessment methods applied (all with scores and classes) were: Mayo (M), Child-Campbell (C), Pugh-Child (P), Pugh-Child-PBC (PP), 'Child-Pugh' (CP), and Ascites Nutritional State-Child (ANS). Fifty percent survival estimates were calculated from Mayo scores. Severity assessment method variables were: ascites (C, P, PP, CP, ANS), encephalopathy (C, P, PP, CP), nutritional state (C, ANS), edema (M), age (M), serum albumin (M, C, P, PP, CP), bilirubin (C, M, P, PP, CP), and prothrombin time (M, P, PP, CP). In 27 out of 32 patients a major event occurred, always between -6 and -0.5 years (median: -1 year) and, never between -16 and -7 years (p < 0.0001). A sign was first observed in 30/32 between -14 and -0.5 years (median: -2 years). Compared to the total population, a sign, and even more so, an event indicated a shorter survival (p = 0.004 and p = 0.0002, respectively). The median 50% estimated survival (predicted by the Mayo model) fitted the actual survival from -6 to -0.5 years (r = -0.7, p < 0.0001), but not from -16 to -7 years (r = -0.1, p = 0.4). All -6 to -0.5-year severity scores correlated (p < 0.0001) both with actual survival (M, C, P, PP, and CP r = 0.7; ANS r = 0.5) and with estimated M 50% survival (C, P, PP, CP r = -0.9; ANS r = -0.6; M score: -0.99), but none with actual survival from -16 to -7 years, except for M, slightly (r = -0.3, p = 0.04). A nomogram for mean C, CP, M and ANS scores related to actual survival was constructed for the -6 to -0.5-year period. The C and CP classes A, B, and C did not appear to distinguish sufficiently into actual survival, whereas the M classes did. The occurrence of a major event appeared to exclude survival over 6 years. In these final 6 years, Child-Campbell, Mayo and Pugh scores correlated equally well with actual survival and better than Ascites/Nutritional State score. In our PBC patients, Campbell was an excellent alternative for Pugh; for Pugh, the original Child-Turcotte variable limits were fully sufficient.
Chen, Wei-Yu; Lin, Hsing-Chieh
2018-05-01
Growing evidence indicates that ocean acidification has a significant impact on calcifying marine organisms. However, there is a lack of exposure risk assessments for aquatic organisms under future environmentally relevant ocean acidification scenarios. The objective of this study was to investigate the probabilistic effects of acidified seawater on the life-stage response dynamics of fertilization, larvae growth, and larvae mortality of the green sea urchin (Strongylocentrotus droebachiensis). We incorporated the regulation of primary body cavity (PBC) pH in response to seawater pH into the assessment by constructing an explicit model to assess effective life-stage response dynamics to seawater or PBC pH levels. The likelihood of exposure to ocean acidification was also evaluated by addressing the uncertainties of the risk characterization. For unsuccessful fertilization, the estimated 50% effect level of seawater acidification (EC50 SW ) was 0.55 ± 0.014 (mean ± SE) pH units. This life stage was more sensitive than growth inhibition and mortality, for which the EC50 values were 1.13 and 1.03 pH units, respectively. The estimated 50% effect levels of PBC pH (EC50 PBC ) were 0.99 ± 0.05 and 0.88 ± 0.006 pH units for growth inhibition and mortality, respectively. We also predicted the probability distributions for seawater and PBC pH levels in 2100. The level of unsuccessful fertilization had 50 and 90% probability risks of 5.07-24.51 (95% CI) and 0-6.95%, respectively. We conclude that this probabilistic risk analysis model is parsimonious enough to quantify the multiple vulnerabilities of the green sea urchin while addressing the systemic effects of ocean acidification. This study found a high potential risk of acidification affecting the fertilization of the green sea urchin, whereas there was no evidence for adverse effects on growth and mortality resulting from exposure to the predicted acidified environment.
Papastergiou, V; Tsochatzis, E A; Rodriquez-Peralvarez, M; Thalassinos, E; Pieri, G; Manousou, P; Germani, G; Rigamonti, C; Arvaniti, V; Karatapanis, S; Burroughs, A K
2013-01-01
Background In primary biliary cirrhosis (PBC), biochemical criteria at 1 year are considered surrogates of response to ursodeoxycholic acid (UDCA). However, due to the slow natural history of PBC, evaluation at 1 year may be suboptimal to assess the therapeutic response, particularly in early disease. Aim To determine whether evaluation of biochemical criteria at 1 year is a reliable surrogate of UDCA response in early PBC. Methods We analysed the prospectively collected data of 215 patients (untreated = 129; UDCA-treated = 86) with early PBC (normal baseline bilirubin/albumin) and a median follow-up of 8 years (range: 1–29.1). The 1-year attainment rates of the Barcelona, Paris-I, Paris-II and Toronto definitions, and their predictive relevance for a poor outcome (death, transplantation, complications of cirrhosis), were assessed either as a result of UDCA or no treatment. Independent associations with attaining each UDCA response definition were identified by multivariate analysis. Results Untreated patients displayed 1-year biochemical features compatible with ‘treatment response’ at rates (Barcelona: 36.4%, Paris-I: 66.7%, Toronto: 59.7%, Paris-II: 40.3%) similar to those obtained under UDCA. Depending on the definition, baseline ALP≤3xULN (OR: 4.80–35.90), AST≤2xULN (OR: 5.63–9.34) and early histological stage (OR: 3.67–3.87) were the stronger predictors for attaining the criteria. UDCA treatment was associated with attaining Barcelona (OR = 2.16) and Paris-II (OR = 2.84), but not Paris-I, and not Toronto definition when excluding late histological cases. Paris-I criteria were significantly predictive of long-term outcomes (HR = 2.83) in untreated patients. Conclusions In early PBC, biochemical criteria at 1 year reflect severity of the disease rather than the therapeutic response to UDCA. PMID:24117847
Zhang, Zhenxiong; Zhang, Cancan; Zhuang, Jianguo; Xu, Fadi
2012-01-01
Our previous study has shown that activating peripheral μ-receptors is necessary for switching the bronchopulmonary C-fibers (PCFs)-mediated rapid shallow breathing (RSB) into an apnea by systemic administration of fentanyl. The brainstem nuclei, such as the medial nucleus tractus solitarius (mNTS) and the Pre-Botzinger Complex (PBC), are required for completing the PCF-mediated respiratory reflexes. Moreover, these areas contain abundant μ-receptors and their activation prolongs expiratory duration (TE). Thus, we asked if central μ-receptors, especially those in the mNTS and PBC, are involved in fully expressing this RSB-apnea switch by fentanyl. In anesthetized rats, the cardiorespiratory responses to right atrial injection of phenylbiguanide (PBG, 3–6 μg/kg) were repeated after: 1) fentanyl (iv), a μ-receptor agonist, alone (8 μg/kg, iv); 2) fentanyl following microinjection of naloxone methiodide (NXM, an opioid receptor antagonist) into the cisterna magna (10 μg/4 μl); 3) the bilateral mNTS (10 mM, 20 nl); or 4) PBC (10 mM, 20 nl). Our results showed that PBG shortened TE by 37 ± 6 % (RSB, from 0.41 ± 0.05 to 0.26 ± 0.03 s, P < 0.01), but it markedly prolonged TE by 5.8-fold (an apnea, from 0.50 ± 0.04 s to 2.9 ± 0.57 s, P < 0.01) after fentanyl (iv). Pretreatment with NXM injected into the cisterna magna or the PBC, but not the mNTS, prevented the fentanyl-induced switch. This study, along with our previous results mentioned above, suggests that although peripheral μ-receptors are essential for triggering the fentanyl-induced switch, central μ-receptors, especially those in the PBC, are required to fully exhibit such switch. PMID:22759907
Cha, S; Leung, P S; Van de Water, J; Tsuneyama, K; Joplin, R E; Ansari, A A; Nakanuma, Y; Schatz, P J; Cwirla, S; Fabris, L E; Neuberger, J M; Gershwin, M E; Coppel, R L
1996-01-01
Dihydrolipoamide acetyltransferase, the E2 component of the pyruvate dehydrogenase complex (PDC-E2), is the autoantigen most commonly recognized by autoantibodies in primary biliary cirrhosis (PBC). We identified a peptide mimotope(s) of PDC-E2 by screening a phage-epitope library expressing random dodecapeptides in the pIII coat protein of fd phage using C355.1, a murine monoclonal antibody (mAb) that recognizes a conformation-dependent epitope in the inner lipoyl domain of PDC-E2 and uniquely stains the apical region of bile duct epithelium (BDE) only in patients with PBC. Eight different sequences were identified in 36 phage clones. WMSYPDRTLRTS was present in 29 clones; WESYPFRVGTSL, APKTYVSVSGMV, LTYVSLQGRQGH, LDYVPLKHRHRH, AALWGVKVRHVS, KVLNRIMAGVRH and GNVALVSSRVNA were singly represented. Three common amino acid motifs (W-SYP, TYVS, and VRH) were shared among all peptide sequences. Competitive inhibition of the immunohistochemical staining of PBC BDE was performed by incubating the peptides WMSYPDRTLRTS, WESYPDRTLRTS, APKTYVSVSGMV, and AALWGVKVRHVS with either C355.1 or a second PDC-E2-specific mAb, C150.1. Both mAbs were originally generated to PDC-E2 but map to distinct regions of PDC-E2. Two of the peptides, although selected by reaction with C355.1, strongly inhibited the staining of BDE by C150.1, whereas the peptide APKTYVSVSGMV consistently inhibited the staining of C355.1 on biliary duct epithelium more strongly than the typical mitochondrial staining of hepatocytes. Rabbit sera raised against the peptide WMSYPDRTLRTS stained BDE of livers and isolated bile duct epithelial cells of PBC patients more intensively than controls. The rabbit sera stained all size ducts in normals, but only small/medium-sized ductules in PBC livers. These studies provide evidence that the antigen present in BDE is a molecular mimic of PDC-E2, and not PDC-E2 itself. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:8855289
Tian, Chenxi; Shi, Herong; Colledge, Clark; Stern, Michael; Waterston, Robert; Liu, Jun
2011-01-01
The proper development of multicellular organisms requires precise regulation and coordination of cell fate specification, cell proliferation and differentiation. Abnormal regulation and coordination of these processes could lead to disease, including cancer. We have examined the function of the sole C. elegans SoxC protein, SEM-2, in the M lineage, which produces the postembryonic mesoderm. We found that SEM-2/SoxC is both necessary and sufficient to promote a proliferating blast cell fate, the sex myoblast fate, over a differentiated striated bodywall muscle fate. A number of factors control the specific expression of sem-2 in the sex myoblast precursors and their descendants. This includes direct control of sem-2 expression by a Hox-PBC complex. The crucial nature of the HOX/PBC factors in directly enhancing expression of this proliferative factor in the C. elegans M lineage suggests a possible more general link between Hox-PBC factors and SoxC proteins in regulating cell proliferation. PMID:21307099
Gardner, Rebecca Ellis; Hausenblas, Heather A
2005-01-01
The purpose of this study was to examine prospectively the ability of direct and belief-based measures of the theory of planned behavior (TPB) constructs to predict exercise and diet intention and behavior of overweight women. Participants were 117 overweight, community-dwelling women and university students enrolled in a 4-week exercise and diet program. Participants completed baseline measures of demographic characteristics and the TPB constructs. Their exercise and diet adherence were also recorded. We found that: (1) the direct measure of perceived behavioral control (PBC) predicted exercise intention, (2) the direct measures of instrumental attitude, subjective norm, and PBC predicted diet intention, and (3) none of the direct or belief-based measures of the TPB constructs predicted 4-week exercise or diet behavior. Furthermore, several beliefs were associated with the direct measures of attitude, subjective norm, PBC, and intention. Implications of these results for designing exercise and diet interventions with overweight women are discussed.
Gao, Chunyan; Xie, Rui; Yu, Chengyuan; Ma, Ruishuang; Dong, Weijun; Meng, Huan; Zhang, Yan; Si, Yu; Zhang, Zhuo; Novakovic, Valerie; Zhang, Yong; Kou, Junjie; Bi, Yayan; Li, Baoxin; Xie, Rujuan; Gilbert, Gary E.; Zhou, Jin; Shi, Jialan
2015-01-01
The mechanisms contributing to an increased risk of thrombosis in uremia are complex and require clarification. There is scant morphological evidence of membrane-dependent binding of factor Xa (FXa) and factor Va (FVa) on endothelial cells (EC) in vitro. Our objectives were to confirm that exposed phosphatidylserine (PS) on microparticle (MP), EC, and peripheral blood cell (PBC) has a prothrombotic role in uremic patients and to provide visible and morphological evidence of PS-dependent prothrombinase assembly in vitro. We found that uremic patients had more circulating MP (derived from PBC and EC) than controls. Additionally, patients had more exposed PS on their MPs and PBCs, especially in the hemodialysis group. In vitro, EC exposed more PS in uremic toxins or serum. Moreover, reconstitution experiments showed that at the early stages, PS exposure was partially reversible. Using confocal microscopy, we observed that PS-rich membranes of EC and MP provided binding sites for FVa and FXa. Further, exposure of PS in uremia resulted in increased generation of FXa, thrombin, and fibrin and significantly shortened coagulation time. Lactadherin, a protein that blocks PS, reduced 80% of procoagulant activity on PBC, EC, and MP. Our results suggest that PBC and EC in uremic milieu are easily injured or activated, which exposes PS and causes a release of MP, providing abundant procoagulant membrane surfaces and thus facilitating thrombus formation. Blocking PS binding sites could become a new therapeutic target for preventing thrombosis. PMID:26580207
Consistent condom use among Thai heterosexual adult males in Bangkok, Thailand.
Janepanish, Poolsuk; Dancy, Barbara L; Park, Chang
2011-04-01
Thai heterosexual males between 20 and 39 years old are at increased risk for HIV infection. Consistent condom use is effective against HIV transmission, but little is known about determinants of consistent condom use for these males. The purpose of this study is to explore determinants of consistent condom use for this population. The determinants of interest are age, educational level, marital status, income, and concepts from the theory of planned behavior: attitude toward condom use, subjective norm about consistent condom use, perceived behavioral control (PBC) of consistent condom use, and intention to use condoms consistently. We used a cross-sectional descriptive research design with a convenience sample of 400 heterosexual Thai males between 20 and 39 years. Our sample had a mean age of 28.71 years (SD = 6.33). During the last three months, 39.5% reported using condoms consistently, 23% reported using condoms inconsistently, and 37.5% reported never using condoms. The results from the regression analyses revealed that marital status, income, subjective norm about consistent condom use, PBC of consistent condom use, and intention to use condoms consistently were determinants of consistent condom use. Also the effect of subjective norm about consistent condom use and PBC of consistent condom use on consistent condom use was mediated by intention to use condoms consistently. These results suggest that interventions to increase consistent condom use should focus on enhancing intention to use condoms consistently by promoting subjective norm about consistent condom use and PBC of consistent condom use.
Kasahara, Kota; Sakuraba, Shun; Fukuda, Ikuo
2018-03-08
We investigate the problem of artifacts caused by the periodic boundary conditions (PBC) used in molecular simulation studies. Despite the long history of simulations with PBCs, the existence of measurable artifacts originating from PBCs applied to inherently nonperiodic physical systems remains controversial. Specifically, these artifacts appear as differences between simulations of the same system but with different simulation-cell sizes. Earlier studies have implied that, even in the simple case of a small model peptide in water, sampling inefficiency is a major obstacle to understanding these artifacts. In this study, we have resolved the sampling issue using the replica exchange molecular dynamics (REMD) enhanced-sampling method to explore PBC artifacts. Explicitly solvated zwitterionic polyalanine octapeptides with three different cubic-cells, having dimensions of L = 30, 40, and 50 Å, were investigated to elucidate the differences with 64 replica × 500 ns REMD simulations using the AMBER parm99SB force field. The differences among them were not large overall, and the results for the L = 30 and 40 Å simulations in the conformational free energy landscape were found to be very similar at room temperature. However, a small but statistically significant difference was seen for L = 50 Å. We observed that extended conformations were slightly overstabilized in the smaller systems. The origin of these artifacts is discussed by comparison to an electrostatic calculation method without PBCs.
Lammers, Willem J; Hirschfield, Gideon M; Corpechot, Christophe; Nevens, Frederik; Lindor, Keith D; Janssen, Harry L A; Floreani, Annarosa; Ponsioen, Cyriel Y; Mayo, Marlyn J; Invernizzi, Pietro; Battezzati, Pier M; Parés, Albert; Burroughs, Andrew K; Mason, Andrew L; Kowdley, Kris V; Kumagi, Teru; Harms, Maren H; Trivedi, Palak J; Poupon, Raoul; Cheung, Angela; Lleo, Ana; Caballeria, Llorenç; Hansen, Bettina E; van Buuren, Henk R
2015-12-01
Approaches to risk stratification for patients with primary biliary cirrhosis (PBC) are limited, single-center based, and often dichotomous. We aimed to develop and validate a better model for determining prognoses of patients with PBC. We performed an international, multicenter meta-analysis of 4119 patients with PBC treated with ursodeoxycholic acid at liver centers in 8 European and North American countries. Patients were randomly assigned to derivation (n = 2488 [60%]) and validation cohorts (n = 1631 [40%]). A risk score (GLOBE score) to predict transplantation-free survival was developed and validated with univariate and multivariable Cox regression analyses using clinical and biochemical variables obtained after 1 year of ursodeoxycholic acid therapy. Risk score outcomes were compared with the survival of age-, sex-, and calendar time-matched members of the general population. The prognostic ability of the GLOBE score was evaluated alongside those of the Barcelona, Paris-1, Rotterdam, Toronto, and Paris-2 criteria. Age (hazard ratio = 1.05; 95% confidence interval [CI]: 1.04-1.06; P < .0001); levels of bilirubin (hazard ratio = 2.56; 95% CI: 2.22-2.95; P < .0001), albumin (hazard ratio = 0.10; 95% CI: 0.05-0.24; P < .0001), and alkaline phosphatase (hazard ratio = 1.40; 95% CI: 1.18-1.67; P = .0002); and platelet count (hazard ratio/10 units decrease = 0.97; 95% CI: 0.96-0.99; P < .0001) were all independently associated with death or liver transplantation (C-statistic derivation, 0.81; 95% CI: 0.79-0.83, and validation cohort, 0.82; 95% CI: 0.79-0.84). Patients with risk scores >0.30 had significantly shorter times of transplant-free survival than matched healthy individuals (P < .0001). The GLOBE score identified patients who would survive for 5 years and 10 years (responders) with positive predictive values of 98% and 88%, respectively. Up to 22% and 21% of events and nonevents, respectively, 10 years after initiation of treatment were correctly reclassified in comparison with earlier proposed criteria. In subgroups of patients aged <45, 45-52, 52-58, 58-66, and ≥66 years, age-specific GLOBE-score thresholds beyond which survival significantly deviated from matched healthy individuals were -0.52, 0.01, 0.60, 1.01 and 1.69, respectively. Transplant-free survival could still be accurately calculated by the GLOBE score with laboratory values collected at 2-5 years after treatment. We developed and validated scoring system (the GLOBE score) to predict transplant-free survival of ursodeoxycholic acid-treated patients with PBC. This score might be used to select strategies for treatment and care. Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.
Liaskou, Evaggelia; Klemsdal Henriksen, Eva Kristine; Holm, Kristian; Kaveh, Fatemeh; Hamm, David; Fear, Janine; Viken, Marte K; Hov, Johannes Roksund; Melum, Espen; Robins, Harlan; Olweus, Johanna; Karlsen, Tom H; Hirschfield, Gideon M
2016-05-01
Hepatic T-cell infiltrates and a strong genetic human leukocyte antigen association represent characteristic features of various immune-mediated liver diseases. Conceptually the presence of disease-associated antigens is predicted to be reflected in T-cell receptor (TCR) repertoires. Here, we aimed to determine if disease-associated TCRs could be identified in the nonviral chronic liver diseases primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC), and alcoholic liver disease (ALD). We performed high-throughput sequencing of the TCRβ chain complementarity-determining region 3 of liver-infiltrating T cells from PSC (n = 20), PBC (n = 10), and ALD (n = 10) patients, alongside genomic human leukocyte antigen typing. The frequency of TCRβ nucleotide sequences was significantly higher in PSC samples (2.53 ± 0.80, mean ± standard error of the mean) compared to PBC samples (1.13 ± 0.17, P < 0.0001) and ALD samples (0.62 ± 0.10, P < 0.0001). An average clonotype overlap of 0.85% was detected among PSC samples, significantly higher compared to the average overlap of 0.77% seen within the PBC (P = 0.024) and ALD groups (0.40%, P < 0.0001). From eight to 42 clonotypes were uniquely detected in each of the three disease groups (≥30% of the respective patient samples). Multiple, unique sequences using different variable family genes encoded the same amino acid clonotypes, providing additional support for antigen-driven selection. In PSC and PBC, disease-associated clonotypes were detected among patients with human leukocyte antigen susceptibility alleles. We demonstrate liver-infiltrating disease-associated clonotypes in all three diseases evaluated, and evidence for antigen-driven clonal expansions. Our findings indicate that differential TCR signatures, as determined by high-throughput sequencing, may represent an imprint of distinctive antigenic repertoires present in the different chronic liver diseases; this thereby opens up the prospect of studying disease-relevant T cells in order to better understand and treat liver disease. © 2015 by the American Association for the Study of Liver Diseases.
Wang, Hefang; Zheng, Hao; Jiang, Zhixiang; Dai, Yanhui; Liu, Guocheng; Chen, Lei; Luo, Xianxiang; Liu, Minhui; Wang, Zhenyu
2017-09-01
Biochar has been suggested as a potential tailored technology for mediating soil conditions and improving crop yields. However, the efficacies of biochar and biochar-based amendments (e.g., composted biochar) in agricultural soils under a rotation system remain uncertain. In this study, an arable soil was subjected to peanut shell biochar (PBC) and biochar-based amendment (PAD) combined with or without nitrogen (N) fertilizer to evaluate their effects on vegetable yield, N bioavailability, and their relative contribution to vegetable biomass in four consecutive planting seasons. PBC alone or in co-application with N fertilizer had little effect on vegetable yield, while PAD co-application with N fertilizer decreased vegetable biomass because of the inhibition of root morphology by excessive nutrient supply. PBC and PAD applications increased rhizosphere soil pH due to OH - and HCO 3 - release and NO 3 - -N uptake. Although the addition of PAD increased soil N contents due to its high contents in PAD, it had little effects on N utilization efficiency (NUE) in the four seasons. The relative contribution of PBC, PAD, and their interaction with N fertilizer to biomass yield was maintained at a low level. Our results indicated that a biochar-based amendment (e.g., PAD) was a potential alternative to N fertilizer, but the ratio of biochar to additives should be managed carefully to generate optimal benefits. Notably, the efficacy of PAD on plant growth was closely associated with plant species, and further related research on different plants is encouraged. Copyright © 2017. Published by Elsevier B.V.
Khorshidi, Abdollah; Ashoor, Mansour
2014-05-01
This study investigates modulation transfer function (MTF) in parallel beam (PB) and fan beam (FB) collimators using the Monte Carlo method with full width at half maximum (FWHM), square and circular-shaped holes, and scatter and penetration (S + P) components. A regulation similar to the lead-to-air ratio was used for both collimators to estimate output data. The hole pattern was designed to compare FB by PB parameters. The radioactive source in air and in a water phantom placed in front of the collimators was simulated using MCNP5 code. The test results indicated that the square holes in PB (PBs) had better FWHM than did the cylindrical (PBc) holes. In contrast, the cylindrical holes in the FB (FBc) had better FWHM than the square holes. In general, the resolution of FBc was better than that of the PBc in air and scatter mediums. The S + P decreased for all collimators as the distance from the source to the collimator surface (z) increased. The FBc had a lower S + P than FBs, but PBc had a higher S + P than PBs. Of the FB and PB collimators with the identical hole shapes, PBs had a smaller S + P than FBs, and FBc had a smaller S + P than PBc. The MTF value for the FB was greater than for the PB and had increased spatial frequency; the FBc had higher MTF than the FBs and PB collimators. Estimating the FB using PB parameters and diverse hole shapes may be useful in collimator design to improve the resolution and efficiency of SPECT images.
PDC-E3BP is not a dominant T-cell autoantigen in primary biliary cirrhosis.
McHugh, Anna; Robe, Amanda J; Palmer, Jeremy M; Jones, David E J
2006-05-01
Autoantibody responses reactive with the E2 and E3BP components of pyruvate dehydrogenase complex (PDC), which characterise primary biliary cirrhosis (PBC) crossreact, precluding the identification, from serological studies, of the antigen to which the principal breakdown of tolerance occurs. Although autoreactive T-cell responses to PDC-E2 have been well characterised it is, at present, unclear whether T-cell tolerance breakdown also occurs to PDC-E3BP. The aims of this study were to characterise autoreactive T-cell responses to PDC-E3BP in PBC and potential factors regulating their expression. Peripheral blood T-cell proliferative responses to purified recombinant human PDC-E2 and PDC-E3BP at a range of concentrations were characterised in PBC patients and control subjects. T-cell proliferative responses to both E2 and E3BP were absent from control subjects (median peak stimulation index (SI) to PDC-E2 1.2 [range 0.3-1.9], 0/10 positive (SI>2.32), median peak SI to PDC-E3BP 1.1 [0.7-2.1
Wang, Lijuan; Zhang, Ying
2016-01-01
This study aimed to use an extended theory of planned behaviour (TPB), which incorporated additional self-efficacy and past behaviour, to predict the intention to engage in moderate-to-vigorous physical activity (MVPA) and the MVPA level of Chinese adolescents. Questionnaires that focused on MVPA, attitude, subjective norm, perceived behavioural control (PBC), self-efficacy and past behaviour related to the MVPA engagement were administered to a sample of 488 young people. Multiple regression analyses provided moderate support for TPB. Three TPB constructs predicted 28.7% of the variance in intentions to engage in MVPA, and that PBC, but not intention, explained 3.4% of the variance in MVPA. Self-efficacy significantly affected intention and behaviour over and above the influence of TPB. Past behaviour had a small but significant improvement in the prediction of intention, but no improvement in the prediction of MVPA. Based on the results, interventions should target adolescent self-efficacy and PBC in physical activity participation.
Ahmad, Mahtab; Lee, Sang Soo; Dou, Xiaomin; Mohan, Dinesh; Sung, Jwa-Kyung; Yang, Jae E; Ok, Yong Sik
2012-08-01
Conversion of crop residues into biochars (BCs) via pyrolysis is beneficial to environment compared to their direct combustion in agricultural field. Biochars developed from soybean stover at 300 and 700 °C (S-BC300 and S-BC700, respectively) and peanut shells at 300 and 700 °C (P-BC300 and P-BC700, respectively) were used for the removal of trichloroethylene (TCE) from water. Batch adsorption experiments showed that the TCE adsorption was strongly dependent on the BCs properties. Linear relationships were obtained between sorption parameters (K(M) and S(M)) and molar elemental ratios as well as surface area of the BCs. The high adsorption capacity of BCs produced at 700 °C was attributed to their high aromaticity and low polarity. The efficacy of S-BC700 and P-BC700 for removing TCE from water was comparable to that of activated carbon (AC). Pyrolysis temperature influencing the BC properties was a critical factor to assess the removal efficiency of TCE from water. Copyright © 2012 Elsevier Ltd. All rights reserved.
Exploring patterns of unwanted behaviours in adults with Prader-Willi syndrome.
Pignatti, Riccardo; Mori, Ileana; Bertella, Laura; Grugni, Graziano; Giardino, Daniela; Molinari, Enrico
2013-11-01
Obsessive-compulsive (O-C) traits, and excessive food intake are well known behavioural manifestations among individuals with Prader-Willi Syndrome (PWS). Other unwanted behaviours are also frequently observed, but they need a more specific investigation, especially in the adult population. The behaviour of 31 PWS adults was investigated via the Symptom Checklist-90-Revised (SCL-90-R), the Yale-Brown Obsessive Compulsive Scale Symptom Checklist (Y-BOCS-SC), and the Prader-Willi Behavioural Checklist (PBC). The PBC is a quick screening questionnaire prompted specifically for the investigation on adults with PWS. Statistical clustering revealed two patterns of unwanted behaviours from the PBC. Behaviours belonging to the first cluster (e.g., Excessive food intake, Skin picking) appear to be linked to the usual phenotypic manifestation of PWS. By contrast, many other behaviours (e.g., some O-C symptoms and aggressive actions) could show a relationship also to individual psychopathologies. Both internal (Anxiety and Depression) and external (Hostility) difficulties in managing impulses should account for individually distinct behaviours in adults with PWS. © 2013 John Wiley & Sons Ltd.
Determinants of physical activity promotion by smoking cessation advisors.
Mas, Sébastien; Bernard, Paquito; Gourlan, Mathieu
2018-05-17
To investigate the cross-sectional association between personal physical activity (PA) level, Theory of Planned Behavior (TPB) constructs toward PA promotion, and PA promotion behavior among smoking cessation advisors. 149 smoking cessation advisors were invited to complete online questionnaires. Hypotheses were tested using Bayesian path analysis. Attitudes and perceived behavioral control (PBC) of smoking cessation advisors were related to PA promotion intentions; intentions were in turn related to PA promotion behaviors. Advisors' personal PA level was indirectly associated with PA promotion behaviors through PBC and PA promotion intentions. The TPB is a relevant theoretical framework with which to explore determinants of PA promotion behavior among smoking cessation advisors. The PA level of health care professionals may be linked to PA promotion behavior through some TPB constructs. Smoking cessation advisor training should include education on attitude development (e.g., PA benefits on smoking cessation), PBC (e.g., modality of PA prescription) and PA promotion intentions (e.g., goal setting). Smoking cessation advisors should also be encouraged to regularly practice PA in order to improve their PA promotion behaviors. Copyright © 2018 Elsevier B.V. All rights reserved.
Zuo, P; Dobbins, R L; O'Connor-Semmes, R L; Young, M A
2016-08-01
A systems model was developed to describe the metabolism and disposition of ursodeoxycholic acid (UDCA) and its conjugates in healthy subjects based on pharmacokinetic (PK) data from published studies in order to study the distribution of oral UDCA and potential interactions influencing therapeutic effects upon interruption of its enterohepatic recirculation. The base model was empirically adapted to patients with primary biliary cirrhosis (PBC) based on current understanding of disease pathophysiology and clinical measurements. Simulations were performed for patients with PBC under two competing hypotheses: one for inhibition of ileal absorption of both UDCA and conjugates and the other only of conjugates. The simulations predicted distinctly different bile acid distribution patterns in plasma and bile. The UDCA model adapted to patients with PBC provides a platform to investigate a complex therapeutic drug interaction among UDCA, UDCA conjugates, and inhibition of ileal bile acid transport in this rare disease population. © 2016 The Authors CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.
Takeshita, Takashi; Yamamoto, Yutaka; Yamamoto-Ibusuki, Mutsuko; Inao, Toko; Sueta, Aiko; Fujiwara, Saori; Omoto, Yoko; Iwase, Hirotaka
2016-05-31
The measurement of circulating cell-free DNA (cfDNA) may transform the management of breast cancer patients. We aimed to investigate the clinical significance of sequential measurements of ESR1 mutations in primary breast cancer (PBC) and metastatic breast cancer (MBC) patients. ESR1 mutations ratio in the PBC groups was used as the minimum cutoff for determining increases in cfDNA ESR1 mutation ratio. An increase in cfDNA ESR1 mutations was found in 13 samples of cfDNA from 12 (28.6%) out of 42 MBC patients. A total of 10 (83.3%) out of 12 MBC patients with increase cfDNA ESR1 mutations showed a poor response to treatment. In survival analysis, increase cfDNA ESR1 mutations may predict a shorter duration of post-endocrine-therapy effectiveness (P = 0.0033). A total of 119 patients (253 plasma samples) with breast carcinoma were enrolled in this study. Cases were selected if archival plasma samples were available from PBC before and after treatment and from MBC gathered more than twice at the time of progression. cfDNA was isolated from the 77 PBC patients (154 plasma samples) and from the 42 MBC patients (99 plasma samples). To investigate any changes in each cfDNA ESR1 mutation before and after treatment, we analyzed the difference with cfDNA ESR1 mutations ratio in the first blood sample using droplet digital polymerase chain reaction (ddPCR). We demonstrate that ddPCR monitoring of the recurrent ESR1 mutation in cfDNA of MBC patients is a feasible and useful method of providing relevant predictive information.
Takeshita, Takashi; Yamamoto, Yutaka; Yamamoto-Ibusuki, Mutsuko; Inao, Toko; Sueta, Aiko; Fujiwara, Saori; Omoto, Yoko; Iwase, Hirotaka
2016-01-01
Background The measurement of circulating cell-free DNA (cfDNA) may transform the management of breast cancer patients. We aimed to investigate the clinical significance of sequential measurements of ESR1 mutations in primary breast cancer (PBC) and metastatic breast cancer (MBC) patients. Results ESR1 mutations ratio in the PBC groups was used as the minimum cutoff for determining increases in cfDNA ESR1 mutation ratio. An increase in cfDNA ESR1 mutations was found in 13 samples of cfDNA from 12 (28.6%) out of 42 MBC patients. A total of 10 (83.3%) out of 12 MBC patients with increase cfDNA ESR1 mutations showed a poor response to treatment. In survival analysis, increase cfDNA ESR1 mutations may predict a shorter duration of post-endocrine-therapy effectiveness (P = 0.0033). Methods A total of 119 patients (253 plasma samples) with breast carcinoma were enrolled in this study. Cases were selected if archival plasma samples were available from PBC before and after treatment and from MBC gathered more than twice at the time of progression. cfDNA was isolated from the 77 PBC patients (154 plasma samples) and from the 42 MBC patients (99 plasma samples). To investigate any changes in each cfDNA ESR1 mutation before and after treatment, we analyzed the difference with cfDNA ESR1 mutations ratio in the first blood sample using droplet digital polymerase chain reaction (ddPCR). Conclusions We demonstrate that ddPCR monitoring of the recurrent ESR1 mutation in cfDNA of MBC patients is a feasible and useful method of providing relevant predictive information. PMID:27102299
2010-01-01
Background Detection of autoantibodies giving nuclear rim pattern by immunofluorescence (anti-nuclear envelope antibodies - ANEA) in sera from patients with primary biliary cirrhosis (PBC) is a useful tool for the diagnosis and prognosis of the disease. Differences in the prevalence of ANEA in PBC sera so far reported have been attributed to the methodology used for the detection as well as to ethnic/geographical variations. Therefore, we evaluated the prevalence of ANEA in sera of Greek patients with PBC by using methods widely used by clinical laboratories and a combination of techniques and materials. Methods We screened 103 sera by immunoblotting on nuclear envelopes and indirect immunofluorescence (IIF) using cells and purified nuclei. Reactivities against specific autoantigens were assessed using purified proteins, ELISA, immunoprecipitation and mass spectrometry. Results We found higher prevalence of ANEA when sera were assayed by IIF on purified nuclei or cultured cells (50%) compared to Hep2 commercially available slides (15%). Anti-gp210 antibodies were identified in 22.3% and 33% of sera using ELISA for the C-terminal of gp210 or both ELISA and immunoprecipitation, respectively. Immunoblotting on nuclear envelopes revealed that immunoreactivity for the 210 kDa zone is related to anti-gp210 antibodies (p < 0.0001). Moreover, we found that sera had antibodies for lamins A (6.8%), B (1%) and C (1%) and LBR (8.7%), whereas none at all had detectable anti-p62 antibodies. Conclusions The prevalence of ANEA or anti-gp210 antibodies is under-estimated in PBC sera which are analyzed by conventional commercially available IIF or ELISA, respectively. Therefore, new substrates for IIF and ELISA should be included by clinical laboratories in the analysis of ANEA in autoimmune sera. PMID:20205958
Meeting Report: Threats to Human Health and Environmental Sustainability in the Pacific Basin
Arnold, Robert G.; Carpenter, David O.; Kirk, Donald; Koh, David; Armour, Margaret-Ann; Cebrian, Mariano; Cifuentes, Luis; Khwaja, Mahmood; Ling, Bo; Makalinao, Irma; Paz-y-Miño, César; Peralta, Genandrialine; Prasad, Rajendra; Singh, Kirpal; Sly, Peter; Tohyama, Chiharu; Woodward, Alistair; Zheng, Baoshan; Maiden, Todd
2007-01-01
The coastal zone of the Pacific Rim is home for about one-third of the world’s population. Disproportionate growth of Far Eastern economies has produced a disproportionate share of related environmental difficulties. As the region searches for acceptable compromises between growth and environmental quality, its influence on global environmental health is certain to increase. Consequences of global environmental change such as habitat alteration, storms, and sealevel rise will be particularly acute among Pacific Rim nations. Adverse health effects from arsenic exposure in Pacific Rim nations have been used to justify drinking water standards in the United States and elsewhere. As global manufacturing in the Pacific Rim increases, the centroid of global air quality and waste management issues will shift further toward Far Eastern nations. The Eleventh International Conference of the Pacific Basin Consortium (PBC) was held in September 2005 in Honolulu, Hawaii. The purpose of the conference was to bring together individuals to discuss regional challenges to sustainable growth. The historic emphasis of the conference on hazardous wastes in relation to human health makes the PBC an ideal forum for discussing technical aspects of sustainable economic growth in the Pacific region. That role is reflected in the 2005 PBC conference themes, which included management of arsenic in potable waters, air quality, climate change, pesticides, mercury, and electronics industry waste—each with emphasis on relationships to human health. Arsenic management exemplifies the manner in which the PBC can focus interdisciplinary discussion in a single technical area. The conference program provided talks on arsenic toxicology, treatment technologies, management of arsenic-bearing residuals from water treatment, and the probable societal costs and benefits of arsenic management. PMID:18087598
Combes, Burton; Luketic, Velimir A.; Peters, Marion G.; Zetterman, Rowen K.; Garcia-Tsao, Guadalupe; Munoz, Santiago J.; Lin, Danyu; Flye, Nancy; Carithers, Robert L.
2013-01-01
OBJECTIVE Randomized, double-blind, placebo-controlled trials of ursodeoxycholic acid (UDCA) in patients with primary biliary cirrhosis (PBC) have not demonstrated improvement in survival during the placebo-controlled phases of these trials. Analyses purporting to demonstrate a survival advantage of UDCA are largely dependent on data obtained after the placebo phases were terminated, and placebo-treated patients were offered open-label UDCA. After completion of our 2-yr placebo-controlled trial of UDCA in which we observed no survival benefit for UDCA, we provided the patients with open-label UDCA to see if delay in providing UDCA for 2 yr had any effect on subsequent liver transplantation or death without liver transplantation. METHODS In our previously reported 2-yr placebo-controlled trial, 151 patients with PBC were randomized to receive either UDCA (n = 77) or placebo (n = 74). The number of patients who progressed to liver transplantation or death without transplantation were similar in both the groups, 12 (16%) in the UDCA-treated and 11 (15%) in placebo-treated patients. All the patients were then offered open-label UDCA, with 61 original UDCA and 56 original placebo-treated patients now taking UDCA in an extended open-label phase of the trial. RESULTS No significant differences were observed in the number of patients who underwent liver transplantation or died without liver transplantation in the open-label phase of the trial. Moreover, no difference in the time to these endpoints was seen over the period of observation of as long as 6 yr from the time of initial randomization. CONCLUSIONS Results of open-label extensions of previous conducted placebo-controlled trials of UDCA in PBC leave uncertain whether UDCA impacts significantly on liver transplantation and death without liver transplantation in patients with PBC. PMID:15046215
Wang, Yandong; Yang, Jun; Liang, Jiping; Qiang, Yanfang; Fang, Shanqi; Gao, Minxue; Fan, Xiaoyu; Yang, Gaihe; Zhang, Baowen; Feng, Yongzhong
2018-08-15
The environmental behavior of farmers plays an important role in exploring the causes of non-point source pollution and taking scientific control and management measures. Based on the theory of planned behavior (TPB), the present study investigated the environmental behavior of farmers in the Water Source Area of the Middle Route of the South-to-North Water Diversion Project in China. Results showed that TPB could explain farmers' environmental behavior (SMC=0.26) and intention (SMC=0.36) well. Furthermore, the farmers' attitude towards behavior (AB), subjective norm (SN), and perceived behavioral control (PBC) positively and significantly influenced their environmental intention; their environmental intention further impacted their behavior. SN was proved to be the main key factor indirectly influencing the farmers' environmental behavior, while PBC had no significant and direct effect. Moreover, environmental knowledge following as a moderator, gender and age was used as control variables to conduct the environmental knowledge on TPB construct moderated mediation analysis. It demonstrated that gender had a significant controlling effect on environmental behavior; that is, males engage in more environmentally friendly behaviors. However, age showed a significant negative controlling effect on pro-environmental intention and an opposite effect on pro-environmental behavior. In addition, environmental knowledge could negatively moderate the relationship between PBC and environmental intention. PBC had a greater impact on the environmental intention of farmers with poor environmental knowledge, compared to those with plenty environmental knowledge. Altogether, the present study could provide a theoretical basis for non-point source pollution control and management. Copyright © 2018 Elsevier B.V. All rights reserved.
Yang, Shi-Gui; Dong, Hong-Jun; Li, Fu-Rong; Xie, Shu-Yun; Cao, Hong-Cui; Xia, Shi-Chang; Yu, Zhao; Li, Lan-Juan
2007-11-01
Scarlet fever is caused by group A beta-hemolytic streptococci (GAS). The clinical syndrome has receded in recent years, but occasionally explosive outbreaks do occur likely due to the emergence of GAS with virulence factors peculiar to this syndrome. Following the notification of an unexpectedly large number of scarlet fever cases amongst adults associated with a school in Ningbo, China, in June 2006, the epidemiological and clinical features of the outbreak were investigated. Logistic regression was conducted to investigate the risk factors of the outbreak and its transmission route. Forty five individuals suffered scarlet fever with an attack rate of 4.98% (45/904). There was a single peak in the epidemic curve, with the majority of the cases occurring during the first two days of the outbreak. The median age of cases was 35.5 years (range 17-65). Most patients had fever (43/45), sore throat (40/45), scarlatinoid rash (39/45) and strawberry-like tongue (30/45). In laboratory detection, 45 cases' throat swabs samples were collected and GAS were isolated from 8 throat swabs samples. All of the cases, except for 2, had eaten the Plain Boiled Chicken (PBC) for lunch on June 6th, and teaching staff and students who had not eaten the PBC were not affected by the epidemic. Logistic regression analysis indicated that PBC was a key risk factor (OR=21.0, P<0.05). The chef of the school refectory was responsible for washing, braising, cutting, and distributing the PBC, and was identified as the likely source. We describe an outbreak of scarlet fever caused by GAS-contaminated food.
Frith, James; Day, Christopher P; Robinson, Lisa; Elliott, Chris; Jones, David E J; Newton, Julia L
2010-01-01
The management of non-alcoholic liver disease (NAFLD) concerns lifestyle modification and exercise; however, adherence is poor. Factors such as lack of confidence to exercise, poor understanding of the benefits of exercise, and a fear of falling all influence engagement in physical activity. To increase exercise in NAFLD it is important to understand the barriers to performing it. Three chronic liver disease cohorts were identified from the Newcastle Liver Database: NAFLD (n=230), alcoholic liver disease (ALD, n=110) and primary biliary cirrhosis (PBC, n=97). Assessment tools were completed by all subjects: Outcome Expectation for Exercise Scale (OEES, understanding the benefits of exercise, lower scores indicate greater understanding), Self-Efficacy for Exercise Scale (SEES, confidence to exercise), Falls Efficacy Scale-International (FES-I, higher scores indicate greater fear of falling). Activity was analysed from a functional perspective using the PROMIS-HAQ. Understanding the benefits of exercise was similar across each group [median OEES scores: NAFLD 2.38 (range 0.0-5.0), ALD 2.25 (0.0-5.0), PBC 2.28 (1.0-5.0), p=0.6]. In NAFLD confidence to exercise was significantly lower [median SEES score 0.0 (0.0-10.0), PBC 4.5 (0.0-10.0), p<0.001]. Fear of falling was similar in NAFLD and PBC, and greatest in ALD [22 (0-64), 22 (3-64), 30 (0-64), p=0.044]. In NAFLD, fear of falling was independently associated with increasing difficulty performing activity. NAFLD patients understand the benefits of exercise but lack confidence to perform it. Fear of falling was independently associated with more difficulty performing activity. Fear of falling and confidence are modifiable and potential targets to improve uptake and adherence for exercise intervention.
Meeting report: threats to human health and environmental sustainability in the pacific basin.
Arnold, Robert G; Carpenter, David O; Kirk, Donald; Koh, David; Armour, Margaret-Ann; Cebrian, Mariano; Cifuentes, Luis; Khwaja, Mahmood; Ling, Bo; Makalinao, Irma; Paz-Y-Miño, César; Peralta, Genandrialine; Prasad, Rajendra; Singh, Kirpal; Sly, Peter; Tohyama, Chiharu; Woodward, Alistair; Zheng, Baoshan; Maiden, Todd
2007-12-01
The coastal zone of the Pacific Rim is home for about one-third of the world's population. Disproportionate growth of Far Eastern economies has produced a disproportionate share of related environmental difficulties. As the region searches for acceptable compromises between growth and environmental quality, its influence on global environmental health is certain to increase. Consequences of global environmental change such as habitat alteration, storms, and sea level rise will be particularly acute among Pacific Rim nations. Adverse health effects from arsenic exposure in Pacific Rim nations have been used to justify drinking water standards in the United States and elsewhere. As global manufacturing in the Pacific Rim increases, the centroid of global air quality and waste management issues will shift further toward Far Eastern nations. The Eleventh International Conference of the Pacific Basin Consortium (PBC) was held in September 2005 in Honolulu, Hawaii. The purpose of the conference was to bring together individuals to discuss regional challenges to sustainable growth. The historic emphasis of the conference on hazardous wastes in relation to human health makes the PBC an ideal forum for discussing technical aspects of sustainable economic growth in the Pacific region. That role is reflected in the 2005 PBC conference themes, which included management of arsenic in potable waters, air quality, climate change, pesticides, mercury, and electronics industry waste-each with emphasis on relationships to human health. Arsenic management exemplifies the manner in which the PBC can focus interdisciplinary discussion in a single technical area. The conference program provided talks on arsenic toxicology, treatment technologies, management of arsenic-bearing residuals from water treatment, and the probable societal costs and benefits of arsenic management.
Cordell, Heather J; Han, Younghun; Mells, George F; Li, Yafang; Hirschfield, Gideon M; Greene, Casey S; Xie, Gang; Juran, Brian D; Zhu, Dakai; Qian, David C; Floyd, James A B; Morley, Katherine I; Prati, Daniele; Lleo, Ana; Cusi, Daniele; Gershwin, M Eric; Anderson, Carl A; Lazaridis, Konstantinos N; Invernizzi, Pietro; Seldin, Michael F; Sandford, Richard N; Amos, Christopher I; Siminovitch, Katherine A
2015-09-22
Primary biliary cirrhosis (PBC) is a classical autoimmune liver disease for which effective immunomodulatory therapy is lacking. Here we perform meta-analyses of discovery data sets from genome-wide association studies of European subjects (n=2,764 cases and 10,475 controls) followed by validation genotyping in an independent cohort (n=3,716 cases and 4,261 controls). We discover and validate six previously unknown risk loci for PBC (Pcombined<5 × 10(-8)) and used pathway analysis to identify JAK-STAT/IL12/IL27 signalling and cytokine-cytokine pathways, for which relevant therapies exist.
Wang, Shengsen; Gao, Bin; Li, Yuncong; Ok, Yong Sik; Shen, Chaofeng; Xue, Shengguo
2017-07-01
In this work, an innovative approach using biochar technology for hyperaccumulator disposal was developed and evaluated. The heavy metal enriched P. acinosa biomass (PBM) was pyrolyzed to produce biochar (PBC). Both PBM and PBC were characterized with X-ray diffraction (XRD) for crystal phases, scanning electron microscopy (SEM) for surface topography, and analyzed for elemental composition and mobility. The results revealed that whewellite, a dominant crystal form in biomass, was decomposed to calcite after pyrolysis. Elemental analysis indicated that 91-99% total non-volatile elements in the biomass were retained in the biochar. The toxicity characteristic leaching procedure (TCLP) results revealed that 94.6% and 0.15% of total Mn was extracted for biomass and biochar, respectively. This suggests that mobility and bioavailability of Mn in biochar was much lower relative to pristine biomass. Batch sorption experiment showed that excellent removal of aqueous silver, lead, cadmium, and copper ions can be achieved with PBC. Findings from this work indicated that biochar technology can provide a value-added solution for hyperaccumulator disposal. Copyright © 2017 Elsevier Ltd. All rights reserved.
Passage-Based Bibliographic Coupling: An Inter-Article Similarity Measure for Biomedical Articles
Liu, Rey-Long
2015-01-01
Biomedical literature is an essential source of biomedical evidence. To translate the evidence for biomedicine study, researchers often need to carefully read multiple articles about specific biomedical issues. These articles thus need to be highly related to each other. They should share similar core contents, including research goals, methods, and findings. However, given an article r, it is challenging for search engines to retrieve highly related articles for r. In this paper, we present a technique PBC (Passage-based Bibliographic Coupling) that estimates inter-article similarity by seamlessly integrating bibliographic coupling with the information collected from context passages around important out-link citations (references) in each article. Empirical evaluation shows that PBC can significantly improve the retrieval of those articles that biomedical experts believe to be highly related to specific articles about gene-disease associations. PBC can thus be used to improve search engines in retrieving the highly related articles for any given article r, even when r is cited by very few (or even no) articles. The contribution is essential for those researchers and text mining systems that aim at cross-validating the evidence about specific gene-disease associations. PMID:26440794
Heirman, Wannes; Walrave, Michel; Ponnet, Koen
2013-02-01
This study adopts a global theoretical framework to predict adolescents' disclosure of personal information in exchange for incentives offered by commercial Websites. The study postulates and tests the validity of a model based on the theory of planned behavior (TPB), including antecedent factors of attitude and perceived behavioral control (PBC). A survey was conducted among 1,042 respondents. Results from SEM analyses show that the hypothesized model fits the empirical data well. The model accounts for 61.9 percent of the variance in adolescents' intention to disclose and 43.7 percent of the variance in self-reported disclosure. Perceived social pressure exerted by significant others (subjective norm) is the most important TPB factor in predicting intention to disclose personal information in exchange for incentives. This finding suggests that in discussions of adolescents' information privacy, the importance of social factors outweighs the individually oriented TPB factors of attitude and PBC. Moreover, privacy concern and trust propensity are significant predictors of respondents' attitudes toward online disclosure in exchange for commercial incentives, whereas the frequency of Internet use significantly affects their level of PBC.
Passage-Based Bibliographic Coupling: An Inter-Article Similarity Measure for Biomedical Articles.
Liu, Rey-Long
2015-01-01
Biomedical literature is an essential source of biomedical evidence. To translate the evidence for biomedicine study, researchers often need to carefully read multiple articles about specific biomedical issues. These articles thus need to be highly related to each other. They should share similar core contents, including research goals, methods, and findings. However, given an article r, it is challenging for search engines to retrieve highly related articles for r. In this paper, we present a technique PBC (Passage-based Bibliographic Coupling) that estimates inter-article similarity by seamlessly integrating bibliographic coupling with the information collected from context passages around important out-link citations (references) in each article. Empirical evaluation shows that PBC can significantly improve the retrieval of those articles that biomedical experts believe to be highly related to specific articles about gene-disease associations. PBC can thus be used to improve search engines in retrieving the highly related articles for any given article r, even when r is cited by very few (or even no) articles. The contribution is essential for those researchers and text mining systems that aim at cross-validating the evidence about specific gene-disease associations.
Cirrhosis and autoimmune liver disease: Current understanding
Liberal, Rodrigo; Grant, Charlotte R
2016-01-01
Primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC) and autoimmune hepatitis (AIH) constitute the classic autoimmune liver diseases (AILDs). While AIH target the hepatocytes, in PBC and PSC the targets of the autoimmune attack are the biliary epithelial cells. Persistent liver injury, associated with chronic AILD, leads to un-resolving inflammation, cell proliferation and the deposition of extracellular matrix proteins by hepatic stellate cells and portal myofibroblasts. Liver cirrhosis, and the resultant loss of normal liver function, inevitably ensues. Patients with cirrhosis have higher risks or morbidity and mortality, and that in the decompensated phase, complications of portal hypertension and/or liver dysfunction lead to rapid deterioration. Accurate diagnosis and monitoring of cirrhosis is, therefore of upmost importance. Liver biopsy is currently the gold standard technique, but highly promising non-invasive methodology is under development. Liver transplantation (LT) is an effective therapeutic option for the management of end-stage liver disease secondary to AIH, PBC and PSC. LT is indicated for AILD patients who have progressed to end-stage chronic liver disease or developed intractable symptoms or hepatic malignancy; in addition, LT may also be indicated for patients presenting with acute liver disease due to AIH who do not respond to steroids. PMID:27729952
Gan, Han M; Lee, Yin P; Austin, Christopher M
2017-01-01
We improved upon the previously reported draft genome of Hydrogenophaga intermedia strain PBC, a 4-aminobenzenesulfonate-degrading bacterium, by supplementing the assembly with Nanopore long reads which enabled the reconstruction of the genome as a single contig. From the complete genome, major genes responsible for the catabolism of 4-aminobenzenesulfonate in strain PBC are clustered in two distinct genomic regions. Although the catabolic genes for 4-sulfocatechol, the deaminated product of 4-aminobenzenesulfonate, are only found in H. intermedia , the sad operon responsible for the first deamination step of 4-aminobenzenesulfonate is conserved in various Hydrogenophaga strains. The absence of pabB gene in the complete genome of H. intermedia PBC is consistent with its p -aminobenzoic acid (pABA) auxotrophy but surprisingly comparative genomics analysis of 14 Hydrogenophaga genomes indicate that pABA auxotrophy is not an uncommon feature among members of this genus. Of even more interest, several Hydrogenophaga strains do not possess the genomic potential for hydrogen oxidation, calling for a revision to the taxonomic description of Hydrogenophaga as "hydrogen eating bacteria."
Zhang, Ni; Campo, Shelly; Yang, Jingzhen; Janz, Kathleen F; Snetselaar, Linda G; Eckler, Petya
2015-01-01
Despite the physical and mental health benefits of leisure-time physical activity (LTPA), only about half of college students participate in the recommended amount of LTPA. While college students are avid users of social network sites (SNSs), whether SNSs would be an effective channel for promoting LTPA through peer social support is unclear. The aim of this study was to explore the effects of social support from students' contacts on SNSs on their intention to participate in LTPA, applying the Theory of Planned Behavior. Participants were recruited through a mass e-mail sent to undergraduate students at a large Midwestern university in fall 2011. In total, 439 surveys were analyzed. Descriptive analyses and analysis for mediating effects were conducted. Social support about LTPA from contacts on SNSs has indirect effect on intention through affective attitude, instrumental attitude, and perceived behavioral control (PBC). The results indicate that social support about LTPA from contacts on SNSs might not be effective to change students' intention unless attitudes and PBC are changed. Future interventions aiming to promote students' intention to participate in LTPA by increasing support from contacts on SNSs should increase affective attitude, instrumental attitude, and PBC at the same time.
The TALE face of Hox proteins in animal evolution.
Merabet, Samir; Galliot, Brigitte
2015-01-01
Hox genes are major regulators of embryonic development. One of their most conserved functions is to coordinate the formation of specific body structures along the anterior-posterior (AP) axis in Bilateria. This architectural role was at the basis of several morphological innovations across bilaterian evolution. In this review, we traced the origin of the Hox patterning system by considering the partnership with PBC and Meis proteins. PBC and Meis belong to the TALE-class of homeodomain-containing transcription factors and act as generic cofactors of Hox proteins for AP axis patterning in Bilateria. Recent data indicate that Hox proteins acquired the ability to interact with their TALE partners in the last common ancestor of Bilateria and Cnidaria. These interactions relied initially on a short peptide motif called hexapeptide (HX), which is present in Hox and non-Hox protein families. Remarkably, Hox proteins can also recruit the TALE cofactors by using specific PBC Interaction Motifs (SPIMs). We describe how a functional Hox/TALE patterning system emerged in eumetazoans through the acquisition of SPIMs. We anticipate that interaction flexibility could be found in other patterning systems, being at the heart of the astonishing morphological diversity observed in the animal kingdom.
The TALE face of Hox proteins in animal evolution
Merabet, Samir; Galliot, Brigitte
2015-01-01
Hox genes are major regulators of embryonic development. One of their most conserved functions is to coordinate the formation of specific body structures along the anterior-posterior (AP) axis in Bilateria. This architectural role was at the basis of several morphological innovations across bilaterian evolution. In this review, we traced the origin of the Hox patterning system by considering the partnership with PBC and Meis proteins. PBC and Meis belong to the TALE-class of homeodomain-containing transcription factors and act as generic cofactors of Hox proteins for AP axis patterning in Bilateria. Recent data indicate that Hox proteins acquired the ability to interact with their TALE partners in the last common ancestor of Bilateria and Cnidaria. These interactions relied initially on a short peptide motif called hexapeptide (HX), which is present in Hox and non-Hox protein families. Remarkably, Hox proteins can also recruit the TALE cofactors by using specific PBC Interaction Motifs (SPIMs). We describe how a functional Hox/TALE patterning system emerged in eumetazoans through the acquisition of SPIMs. We anticipate that interaction flexibility could be found in other patterning systems, being at the heart of the astonishing morphological diversity observed in the animal kingdom. PMID:26347770
Wang, Ting; Sun, Hongwen; Ren, Xinhao; Li, Bing; Mao, Hongjun
2018-02-01
Two kinds of biochars, one derived from corn straw (CBC) and one from pig manure (PBC), were used as the carriers of a bacterium (B38) to adsorb heavy metals in solution. CBC exhibited high affinity to Hg(II), while PBC showed large adsorption capacity of Pb(II). After loading with B38, the sorption capacity of the co-sorbents were enhanced for Pb(II), but weakened for Hg(II). In a binary system, the overall adsorption capacity to Hg-Pb (CBC+B38, 136.7mg/g; PBC+B38, 181.3mg/g) on co-sorbents was equal to the sum of the single-component values for Hg(II) and Pb(II). Electrostatic interactions and precipitation are the major mechanisms in the adsorption of Hg(II). In contrast, cation-π interactions and precipitation were involved in the sorption process of Pb(II). Moreover, the sorption sites of Hg(II) and Pb(II) partially overlapped on the biochar surface, but were different on co-sorbents. Hence, the co-sorbents have an advantage over the biochar alone in the removal of heavy metal mixtures. Copyright © 2017 Elsevier Inc. All rights reserved.
Ursodeoxycholic acid treatment of vanishing bile duct syndromes
Pusl, Thomas; Beuers, Ulrich
2006-01-01
Vanishing bile duct syndromes (VBDS) are characterized by progressive loss of small intrahepatic ducts caused by a variety of different diseases leading to chronic cholestasis, cirrhosis, and premature death from liver failure. The majority of adult patients with VBDS suffer from primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC). Ursodeoxycholic acid (UDCA), a hydrophilic dihydroxy bile acid, is the only drug currently approved for the treatment of patients with PBC, and anticholestatic effects have been reported for several other cholestatic syndromes. Several potential mechanisms of action of UDCA have been proposed including stimulation of hepatobiliary secretion, inhibition of apoptosis and protection of cholangiocytes against toxic effects of hydrophobic bile acids. PMID:16773706
Linking matrices in systems with periodic boundary conditions
NASA Astrophysics Data System (ADS)
Panagiotou, Eleni; Millett, Kenneth C.
2018-06-01
We study the linking matrix, a measure of entanglement for a collection of closed or open chains in 3-space based on the Gauss linking number. Periodic boundary conditions (PBC) are often used in the simulation of physical systems of filaments. To measure entanglement of closed or open chains in systems employing PBC we use the periodic linking matrix, based on the periodic linking number, defined in Panagiotou (2015 J. Comput. Phys. 300 533–73). We study the properties of the periodic linking matrix as a function of cell size. We provide analytical results concerning the eigenvalues of the periodic linking matrix and show that some of them are invariant of cell-size.
High polarization purity operation of 99% in 9xx-nm broad stripe laser diodes
NASA Astrophysics Data System (ADS)
Morohashi, Rintaro; Yamagata, Yuji; Kaifuchi, Yoshikazu; Tada, Katsuhisa; Nogawa, Ryozaburo; Yamada, Yumi; Yamaguchi, Masayuki
2018-02-01
Polarization characteristics of self-aligned stripe (SAS) laser diodes (LDs) and Ridge-LDs are investigated to realize highly efficient polarization beam combined (PBC) LD modules. Vertical layers of both lasers are designed identically. Near field patterns (NFP) of TM polarization for the Ridge-LD showed peaks at the side edges, as expected by the strain simulation. On the other hand, SAS-LD showed a relatively flat and weak profile. Polarization purity (ITE/ (ITE+ITM)) of SAS-LDs exceeds 99%, while those of the Ridge-LDs are as low as 96%. It is confirmed that our SAS-LDs are suitable sources for PBC with low power loss.
VizieR Online Data Catalog: New gamma-ray blazar candidates in the 3PBC (Maselli+, 2013)
NASA Astrophysics Data System (ADS)
Maselli, A.; Massaro, F.; Cusumano, G.; D'Abrusco, R.; La Parola, V.; Paggi, A.; Segreto, A.; Smith, H. A.; Tosti, G.
2013-06-01
We searched for γ-ray blazar candidates among the 382 unidentified hard X-ray sources of the third Palermo BAT Catalog (3PBC) obtained from the analysis of 66 months of Swift Burst Alert Telescope (BAT) survey data and listing 1586 sources. We adopted a recently developed association method based on the peculiar infrared colors that characterize the γ-ray blazars included in the second catalog of active galactic nuclei detected by the Fermi Large Area Telescope. We used this method exploiting the data of the all-sky survey performed by the Wide-field Infrared Survey Explorer (WISE) to establish correspondences between unidentified 3PBC sources and WISE γ-ray blazar candidates located within the BAT positional uncertainty region at a 99% confidence level. We obtained a preliminary list of candidates for which we analyzed all the available data in the Swift archive to complement the information in the literature and in the radio, infrared, and optical catalogs with the information on their optical-UV and soft X-ray emission. Requiring the presence of radio and soft X-ray counterparts consistent with the infrared positions of the selected WISE sources, as well as a blazar-like radio morphology, we finally obtained a list of 24 γ-ray blazar candidates. (2 data files).
Autoimmune liver disease 2007.
Muratori, Paolo; Granito, Alessandro; Pappas, Georgios; Muratori, Luigi; Lenzi, Marco; Bianchi, Francesco B
2008-01-01
Autoimmune liver disease (ALD) includes a spectrum of diseases which comprises both cholestatic and hepatitic forms: autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC) and the so called "overlap" syndromes where hepatitic and cholestatic damage coexists. All these diseases are characterized by an extremely high heterogeneity of presentation, varying from asymptomatic, acute (as in a subset of AIH) or chronic (with aspecific symptoms such as fatigue and myalgia in AIH or fatigue and pruritus in PBC and PSC). The detection and characterization of non organ specific autoantibodies plays a major role in the diagnostic approach of autoimmune liver disease; anti nuclear reactivities (ANA) and anti smooth muscle antibodies (SMA) mark type 1 AIH, liver kidney microsomal antibody type 1 (LKM1) and liver cytosol type 1 (LC1) are the serological markers of type 2 AIH; antimitochondrial antibodies (AMA) are associated with PBC, while no specific marker is found in PSC, since anticytoplasmic neutrophil antibodies with perinuclear pattern (atypical p-ANCA or p-ANNA) are also detected in a substantial proportion of type 1 AIH cases. Treatment options rely on immunosoppressive therapy (steroids and azathioprine) in AIH and on ursodeoxycholic acid in cholestatic conditions; in all these diseases liver transplantation remains the only therapeutical approach for the end stage of liver disease.
Adair, Frank W.; Geftic, Sam G.; Gelzer, Justus
1969-01-01
Resistant cells of Pseudomonas aeruginosa and a waterborne Pseudomonas sp. (strain Z-R) were able to multiply in nitrogen-free minimal salts solution containing various concentrations of commercially prepared, ammonium acetate-buffered benzalkonium chloride (CBC), a potent antimicrobial agent. As the CBC concentration increased, growth increased until a point was reached at which the extent of growth leveled off or was completely depressed. Minimal salts solutions of pure benzalkonium chloride (PBC) containing no ammonium acetate did not support bacterial growth. When ammonium acetate was added to PBC solutions in the same concentrations found in CBC solutions, growth patterns developed that were comparable to those found with CBC. Likewise, (NH4)2SO4 added to PBC solutions supported growth of both organisms. P. aeruginosa was initially resistant to CBC levels of 0.02% and it was adapted to tolerate levels as high as 0.36%. Strain Z-R was naturally resistant to 0.4% CBC. Since ammonium acetate, carried over by the CBC used in drug formulations and disinfectant solutions, has the potential to support the growth of resistant bacteria and thus make possible the risk of serious infection, it is suggested that regulations allowing the presence of ammonium acetate in CBC solution be reconsidered. PMID:4984761
Dzul-Caamal, Ricardo; Hernández-López, Abigail; Gonzalez-Jáuregui, Mauricio; Padilla, Sergio E; Girón-Pérez, Manuel Ivan; Vega-López, Armando
2016-10-01
In this study, we assessed the effects of inorganic and organic pollutants [As, Cu, Fe, Mn, Pb, Zn, PAHs (11 compounds) and total phenols] from a panel of biomarkers [O2, H2O2, thiobarbituric acid reactive substances (TBARS), carbonyl proteins (RCO), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and total cytochrome P450 activities] evaluated in the Snout Scraping (SS), Serum (S) and Peripheral Blood Cells (PBC) of the Morelet's crocodile (Crocodylus moreletii) inhabiting the reference locality (Lake Mocu) and polluted locality (Champoton River) using Principal Component Analysis (PCA). In male crocodiles from the reference site, only H2O2 in PBC was related to levels of fluoranthene on the Keel of Caudal Scales (KCS), but, in females, no association was detected. In contrast, a sex-linked response was detected in specimens from the polluted locality. Levels of benzo[a]pyrene, benzo[a]anthracene, chrysene, pyrene, phenanthrene, acenaphthene, Zn, Cu, and Pb in KCS of the female crocodil were related to the oxidative stress biomarkers on PBC, incluing the total CYP450 activity and levels of O2, H2O2 in serum. However, in male crocodiles, the oxidative stress in SS and in the serum (TBARS, RCO, CAT, GPx), and SOD in PBC was related to As, Pb, Cu, Fe, and benzo[a]pyrene water concentrations and to the burdens of As, Fe, Mn, indeno[1,2,3cd]pyrene in KCS. These results confirm the usefulness of minimal or non-invasive methods of evaluating the oxidative stress response for the environmental monitoring program on the wild Morelet's crocodile that is subject to special protection in Mexican guidelines. Copyright © 2016 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Mari, X.; Thuoc, C. V.; Guinot, B. P.; Brune, J.; Lefebvre, J. P.; Raimbault, P.; Niggemann, J.; Dittmar, T.
2016-02-01
Black Carbon (BC) is an aerosol emitted during biomass burning and fossil fuel combustion. On a global scale, BC deposits on the ocean at a rate of 12-45 Tg per year, with higher fluxes in the northern hemisphere and in inter-tropical regions, following the occurrence of hotspots of atmospheric BC concentration. In the present study conducted in a coastal site located in a regional hotspot of atmospheric BC concentration, North Vietnam, we monitored the seasonal variations of atmospheric and marine BC during an annual cycle. Atmospheric BC followed a seasonal pattern characterized by high concentrations during the dry season, i.e. from October to April, and low concentrations during the wet season, i.e. from May to September. This trend is linked to a change in wind regime, with air masses originating from the North during the dry season and from the South during the wet season. On average, the contribution of BC to the particulate and the dissolved organic carbon pools was 43% and 3%, respectively. The concentration of particulate BC (PBC) was on average 50 times higher in the surface microlayer (SML) than in the water column. In the water column, the concentration of PBC was higher during the dry season than the wet season, which is consistent with variations of atmospheric BC concentrations. On the contrary, the concentration of dissolved BC (DBC) was lower during the dry season than the wet season. This seasonal pattern suggests that PBC concentration in coastal marine systems depends upon atmospheric BC concentration, while increased DBC concentration is linked to rainy conditions. The deposition of BC during the dry season was concomitant with a strong enrichment of organic phosphorus in the SML. During the annual cycle, the POC:DOC ratio was positively correlated with the concentration of PBC, suggesting adsorption of DOC onto BC particles and formation of POC via stimulation of aggregation processes.
Is osteoporosis a peculiar association with primary biliary cirrhosis?
Floreani, Annarosa; Mega, Andrea; Camozzi, Valentina; Baldo, Vincenzo; Plebani, Mario; Burra, Patrizia; Luisetto, Giovanni
2005-01-01
AIM: (1) To compare the prevalence of osteoporosis (t-score ≤ -2.5 SD) between stage IV PBC patients, and two groups of age- and sex-matched controls: one with hepatitis C virus (HCV)-related cirrhosis, and the other one consisting of a group of healthy subjects from the general population; (2) to identify the main risk factors for the development of bone loss. METHODS: Thirty-five stage IV PBC patients (mean age 52.5 ± 10 years), 49 females with HCV-related cirrhosis (mean age 52.9 ± 5.8 years) and 33 healthy females (mean age 51.8 ± 2.22 years) were enrolled in the study. Bone metabolism was evaluated by measuring serum calcium corrected for serum albumin (Ca corr.), 25-hydroxy vitamin D (25-OH vit D), parathyroid hormone, osteocalcin. Bone mineral density (BMD) was assessed at the lumbar spine by dual-photon X-ray absorptiometry. RESULTS: Osteoporosis was present in 5/35 PBC patients (14.2%) and in 7/49 HCV-related cirrhotic patients (14.3%), without any statistical difference between the two groups. Among healthy control subjects, none had osteoporosis. No difference was found between the three groups in serum parameters of bone metabolism. Univariate analysis showed that menopausal state and low BMI were significantly correlated with osteoporosis. Multivariate regression analysis showed that menopausal status, BMI < 23, and old age were independent variables significantly correlated with osteoporosis. CONCLUSION: PBC in itself has no negative influence on BMD. End-stage liver disease patients carry a disease-specific risk for osteoporosis, but have an effective risk of bone loss in relation to individual potential risk for each patient. A practical message should be taken into account, that is, every effort should be made to prevent osteoporosis when a patient has simple osteopenia, or if it is a woman in or near menopausal age. PMID:16149144
Umemura, Takeji; Joshita, Satoru; Sekiguchi, Tomohiro; Usami, Yoko; Shibata, Soichiro; Kimura, Takefumi; Komatsu, Michiharu; Matsumoto, Akihiro; Ota, Masao; Tanaka, Eiji
2015-06-01
Noninvasive markers of liver fibrosis in patients with primary biliary cirrhosis (PBC) are needed for predicting disease progression. As the Wisteria floribunda agglutinin-positive Mac-2-binding protein (WFA(+)-M2BP) was recently established as a liver fibrosis glycobiomarker in chronic hepatitis C, we assessed its efficacy in evaluating liver fibrosis stage and disease progression in PBC. A total of 137 patients with PBC who underwent liver biopsy and serological tests for WFA(+)-M2BP were enrolled. All patients were treated with ursodeoxycholic acid. Clinical data were compared with those for other noninvasive markers (aspartate aminotransferase-to-platelet ratio, FIB-4 index, aspartate aminotransferase/alanine aminotransferase ratio, Forn's index, and Mayo score) for estimating liver fibrosis using receiver operating characteristic analysis. The association between WFA(+)-M2BP and clinical outcome (liver decompensation, liver transplantation, or death) was evaluated using the Cox proportional hazards model with stepwise method. WFA(+)-M2BP was independently associated with liver fibrosis stage as determined by liver biopsy. The cutoff values of WFA(+)-M2BP for fibrosis stages ≥F1, ≥F2, ≥F3, and F4 were 0.7, 1.0, 1.4, and 2.0, respectively. The area under the receiver operating characteristic curve values for significant fibrosis, severe fibrosis, and cirrhosis were 0.979, 0.933, and 0.965, respectively. WFA(+)-M2BP was significantly superior to the other indices for the determination of significant and severe fibrosis stages. Furthermore, the WFA(+)-M2BP level at enrollment was strongly and independently associated with clinical outcome (hazard ratio 18.59, P=0.021). Baseline measurements of WFA(+)-M2BP represent a simple and reliable noninvasive surrogate marker of liver fibrosis and prognosis in patients with PBC.
Savio, Andrea J.; Lemire, Mathieu; Mrkonjic, Miralem; Gallinger, Steven; Zanke, Brent W.; Hudson, Thomas J.; Bapat, Bharati
2012-01-01
Single nucleotide polymorphisms (SNPs) are the most common form of genetic variation. We previously demonstrated that SNPs (rs1800734, rs749072, and rs13098279) in the MLH1 gene region are associated with MLH1 promoter island methylation, loss of MLH1 protein expression, and microsatellite instability (MSI) in colorectal cancer (CRC) patients. Recent studies have identified less CpG-dense “shore” regions flanking many CpG islands. These shores often exhibit distinct methylation profiles between different tissues and matched normal versus tumor cells of patients. To date, most epigenetic studies have focused on somatic methylation events occurring within solid tumors; less is known of the contributions of peripheral blood cell (PBC) methylation to processes such as aging and tumorigenesis. To address whether MLH1 methylation in PBCs is correlated with tumorigenesis we utilized the Illumina 450 K microarrays to measure methylation in PBC DNA of 846 healthy controls and 252 CRC patients from Ontario, Canada. Analysis of a region of chromosome 3p21 spanning the MLH1 locus in healthy controls revealed that a CpG island shore 1 kb upstream of the MLH1 gene exhibits different methylation profiles when stratified by SNP genotypes (rs1800734, rs749072, and rs13098279). Individuals with wild-type genotypes incur significantly higher PBC shore methylation than heterozygous or homozygous variant carriers (p<1.1×10−6; ANOVA). This trend is also seen in CRC cases (p<0.096; ANOVA). Shore methylation also decreases significantly with increasing age in cases and controls. This is the first study of its kind to integrate PBC methylation at a CpG island shore with SNP genotype status in CRC cases and controls. These results indicate that CpG island shore methylation in PBCs may be influenced by genotype as well as the normal aging process. PMID:23240038
Quantitative HER2 and p95HER2 levels in primary breast cancers and matched brain metastases.
Duchnowska, Renata; Sperinde, Jeff; Chenna, Ahmed; Huang, Weidong; Weidler, Jodi M; Winslow, John; Haddad, Mojgan; Paquet, Agnes; Lie, Yolanda; Trojanowski, Tomasz; Mandat, Tomasz; Kowalczyk, Anna; Czartoryska-Arłukowicz, Bogumiła; Radecka, Barbara; Jarosz, Bożena; Staszkiewicz, Rafal; Kalinka-Warzocha, Ewa; Chudzik, Małgorzata; Biernat, Wojciech; Jassem, Jacek
2015-09-01
Patients with advanced breast cancer positive for human epidermal growth factor receptor 2 (HER2) are at high risk for brain metastasis (BM). The prevalence and significance of expression of HER2 and its truncated form p95HER2 (p95) in BM is unknown. Seventy-five pairs of formalin-fixed paraffin-embedded samples from matched primary breast cancers (PBCs) and BM were assayed for quantitative p95 and HER2-total (H2T) protein expression using the p95 VeraTag and HERmark assays, respectively. There was a net increase in p95 and H2T expression in BM relative to the matched PBC (median 1.5-fold, P = .0007 and 2.1-fold, P < .0001, respectively). Cases with H2T-positive tumors were more likely to have the largest (≥5-fold) increase in p95 (odds ratio = 6.3, P = .018). P95 positivity in PBC correlated with progression-free survival (hazard ratio [HR] = 2.2, P = .013), trended with shorter time to BM (HR = 1.8, P = .070), and correlated with overall survival (HR = 2.1, P = .042). P95 positivity in BM correlated with time to BM (HR = 2.0, P = .016) but did not correlate with overall survival from the time of BM diagnosis (HR = 1.2, P = .61). This is the first study of quantitative p95 and HER2 expression in matched PBC and BM. BM of breast cancer shows significant increases in expression of both biomarkers compared with matched PBC. These data provide a rationale for future correlative studies on p95 and HER2 levels in BM. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
The effect of storage temperature and duration on the microbial quality of bulk tank milk.
O'Connell, A; Ruegg, P L; Jordan, K; O'Brien, B; Gleeson, D
2016-05-01
The dairy industry in Ireland is currently undergoing a period of expansion and, as a result, it is anticipated that milk may be stored in bulk tanks on-farm for periods greater than 48 h. The objective of this study was to investigate the effects of storage temperature and duration on microbial quality of bulk tank milk when fresh milk is added to the bulk tank twice daily. Bulk tank milk stored at 3 temperatures was sampled at 24-h intervals during storage periods of 0 to 96 h. Bulk tank milk samples were analyzed for total bacterial count (TBC), psychrotrophic bacterial count (PBC), laboratory pasteurization count (LPC), psychrotrophic-thermoduric bacterial count (PBC-LPC), proteolytic bacterial count, lipolytic bacterial count, presumptive Bacillus cereus, sulfite-reducing Clostridia (SRC), and SCC. The bulk tank milk temperature was set at each of 3 temperatures (2°C, 4°C, and 6°C) in each of 3 tanks on 2 occasions during two 6-wk periods. Period 1 was undertaken in August and September, when all cows were in mid lactation, and period 2 was undertaken in October and November, when all cows were in late lactation. None of the bulk tank bacterial counts except the proteolytic count were affected by lactation period. The proteolytic bacterial count was greater in period 2 than in period 1. The TBC and PBC of milk stored at 6°C increased as storage duration increased. The TBC did not increase with increasing storage duration when milk was stored at 2°C or 4°C but the PBC of milk stored at 4°C increased significantly between 0 and 96 h. The numbers of proteolytic and lipolytic bacteria, LPC, or PBC-LPC in bulk tank milk were not affected by temperature or duration of storage. Presumptive B. cereus were detected in 10% of all bulk tank milk samples taken over the two 6-wk periods, with similar proportions observed in both. In bulk tank milk samples, a greater incidence of SRC was observed in period 2 (20%) compared with period 1 (3%). Milk produced on-farm with minimal bacterial contamination can be successfully stored at 2°C and 4°C for up to 96h with little effect on its microbial quality. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Dinani, Amreen M; Fischer, Sandra E; Mosko, Jeff; Guindi, Maha; Hirschfield, Gideon M
2012-06-01
Patients with autoimmune hepatitis (AIH) who have antibodies against mitochondrial proteins (AMA positive) are believed to have an autoimmune syndrome that should be managed as AIH. Of patients with AMA-positive AIH, we report on 3 individuals to demonstrate how autoimmune liver disease can progress over time. Specific features of primary biliary cirrhosis (PBC) overlapped in time in these patients. Our observations indicate the importance of careful follow up of patients with AMA-positive AIH; health care professionals that treat such patients should therefore be aware of longitudinal clinical changes that might indicate development of PBC in this setting. Copyright © 2012 AGA Institute. Published by Elsevier Inc. All rights reserved.
Tipton, Julia A
2014-01-01
The purpose of this correlational study was to determine the ability the Theory of Planned Behavior (TPB) to explain caregivers' intention to serve sugar-sweetened beverages to non-Hispanic black preschoolers. A sample of 165 caregivers of non-Hispanic black children preschoolers completed a written questionnaire. Multiple regression with path analysis confirmed the relationships of attitude and subjective norm, but not perceived behavioral control (PBC),with intention. After removing PBC, the model accounted for 45.1% of variance in intention. Nurses and other health care professionals can use these findings to tailor behaviorally-based obesity prevention programs at the individual, family, and community-based levels. Copyright © 2014 Elsevier Inc. All rights reserved.
Medical treatment of primary biliary cirrhosis and primary sclerosing cholangitis.
Holtmeier, J; Leuschner, U
2001-01-01
Treatment of primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) with ursodeoxycholic acid (UDCA) has been in common use since 1985. In PBC, treatment with UDCA improves laboratory data, liver histology, enables a longer transplantation-free interval and prolongs disease survival. Because UDCA is unable to cure the disease newer drugs or combination therapies are still needed. Studies with UDCA and immunosuppressants such as prednisone, budesonide and azathioprine have shown that in selected patients combination therapy may be superior to UDCA monotherapy. PSC is treated successfully with UDCA and endoscopic dilatation of the bile duct strictures. Treatment of extrahepatic manifestations of cholestatic liver disease such as pruritus, fatigue, osteoporosis and steatorrhea can be problematic and time-consuming. Copyright 2001 S. Karger AG, Basel
[Autoimmune hepatitis: Immunological diagnosis].
Brahim, Imane; Brahim, Ikram; Hazime, Raja; Admou, Brahim
2017-11-01
Autoimmune hepatopathies (AIHT) including autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC) and autoimmune cholangitis (AIC), represent an impressive entities in clinical practice. Their pathogenesis is not perfectly elucidated. Several factors are involved in the initiation of hepatic autoimmune and inflammatory phenomena such as genetic predisposition, molecular mimicry and/or abnormalities of T-regulatory lymphocytes. AIHT have a wide spectrum of presentation, ranging from asymptomatic forms to severe acute liver failure. The diagnosis of AIHT is based on the presence of hyperglobulinemia, cytolysis, cholestasis, typical even specific circulating auto-antibodies, distinctive of AIH or PBC, and histological abnormalities as well as necrosis and inflammation. Anti-F actin, anti-LKM1, anti-LC1 antibodies permit to distinguish between AIH type 1 and AIH type 2. Anti-SLA/LP antibodies are rather associated to more severe hepatitis, and particularly useful for the diagnosis of seronegative AIH for other the antibodies. Due to the relevant diagnostic value of anti-M2, anti-Sp100, and anti-gp210 antibodies, the diagnosis of PBC is more affordable than that of PSC and AIC. Based on clinical data, the immunological diagnosis of AIHT takes advantage of the various specialized laboratory techniques including immunofluorescence, immunodot or blot, and the Elisa systems, provided of a closer collaboration between the biologist and the physician. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Kotb, Magd A
2012-01-01
Ursodeoxycholic acid (UDCA) is a steroid bile acid approved for primary biliary cirrhosis (PBC). UDCA is reported to have "hepato-protective properties". Yet, UDCA has "unanticipated" toxicity, pronounced by more than double number of deaths, and eligibility for liver transplantation compared to the control group in 28 mg/kg/day in primary sclerosing cholangitis, necessitating trial halt in North America. UDCA is associated with increase in hepatocellular carcinoma in PBC especially when it fails to achieve biochemical response (10 and 15 years incidence of 9% and 20% respectively). "Unanticipated" UDCA toxicity includes hepatitis, pruritus, cholangitis, ascites, vanishing bile duct syndrome, liver cell failure, death, severe watery diarrhea, pneumonia, dysuria, immune-suppression, mutagenic effects and withdrawal syndrome upon sudden halt. UDCA inhibits DNA repair, co-enzyme A, cyclic AMP, p53, phagocytosis, and inhibits induction of nitric oxide synthatase. It is genotoxic, exerts aneugenic activity, and arrests apoptosis even after cellular phosphatidylserine externalization. UDCA toxicity is related to its interference with drug detoxification, being hydrophilic and anti-apoptotic, has a long half-life, has transcriptional mutational abilities, down-regulates cellular functions, has a very narrow difference between the recommended (13 mg/kg/day) and toxic dose (28 mg/kg/day), and it typically transforms into lithocholic acid that induces DNA strand breakage, it is uniquely co-mutagenic, and promotes cell transformation. UDCA beyond PBC is unjustified.
Fan, Zixi; Zhang, Qian; Li, Meng; Niu, Dongyuan; Sang, Wenjiao; Verpoort, Francis
2018-03-01
In this work, a KMnO 4 -modified-biochar-based composite material with manganese oxide produced at 600 °C was fabricated to investigate the sorption mechanism of Cd(II) and to comprehensively evaluate the effect of the modification on biochar properties. Cd(II) adsorption mechanisms were mainly controlled by interaction with minerals, complexation with oxygen-containing functional groups, and cation-π interaction. The sorption capacity was significantly reduced after a deash treatment of biochar, almost shrunk by 3 and 3.5 times for pristine biochar (PBC) and modified biochar (MBC). For deashed PBC, oxygen-containing functional groups were the main contributor toward Cd(II) adsorption while interaction with minerals was significantly compromised and became negligible. The sorption capacity was also apparently decreased after the deash treatment of MBC; however, for deashed MBC, interaction with minerals still was the main contributor to the sorption ability, which could be attributed to the mechanism of interaction of Cd(II) with loaded MnO x on biochar. Cation-π interaction in MBC was notably enhanced compared to PBC due to the oxidation of KMnO 4 on biomass. Also, sorption performance by oxygen-containing functional groups was also enhanced. Hence, the modification by KMnO 4 has a significant effect on the Cd(II) sorption performance of biochar.
Kotb, Magd A.
2012-01-01
Ursodeoxycholic acid (UDCA) is a steroid bile acid approved for primary biliary cirrhosis (PBC). UDCA is reported to have “hepato-protective properties”. Yet, UDCA has “unanticipated” toxicity, pronounced by more than double number of deaths, and eligibility for liver transplantation compared to the control group in 28 mg/kg/day in primary sclerosing cholangitis, necessitating trial halt in North America. UDCA is associated with increase in hepatocellular carcinoma in PBC especially when it fails to achieve biochemical response (10 and 15 years incidence of 9% and 20% respectively). “Unanticipated” UDCA toxicity includes hepatitis, pruritus, cholangitis, ascites, vanishing bile duct syndrome, liver cell failure, death, severe watery diarrhea, pneumonia, dysuria, immune-suppression, mutagenic effects and withdrawal syndrome upon sudden halt. UDCA inhibits DNA repair, co-enzyme A, cyclic AMP, p53, phagocytosis, and inhibits induction of nitric oxide synthatase. It is genotoxic, exerts aneugenic activity, and arrests apoptosis even after cellular phosphatidylserine externalization. UDCA toxicity is related to its interference with drug detoxification, being hydrophilic and anti-apoptotic, has a long half-life, has transcriptional mutational abilities, down-regulates cellular functions, has a very narrow difference between the recommended (13 mg/kg/day) and toxic dose (28 mg/kg/day), and it typically transforms into lithocholic acid that induces DNA strand breakage, it is uniquely co-mutagenic, and promotes cell transformation. UDCA beyond PBC is unjustified. PMID:22942741
Paredes Millán, Mileydy; Chirinos Montes, Nataly Juliana; Martinez Apaza, Anthony; Lozano, Adelina
2014-01-01
To identify the most common autoimmune rheumatic diseases in patients with autoimmune liver disease in the Hospital Arzobispo Loayza (HAL) from 2008 -2013. This is a transversal and descriptive study, we analyzed 125 medical records, only 86 patients fulfill the diagnostic criteria for autoimmune liver disease, of whom 46 had diagnosis of autoimmune hepatitis(AIH), 39 primary biliary cirrhosis(PBC) and just 1 primary sclerosing cholangitis (PSC). In our study group we looked for the clinical and laboratory characteristics most common and the frequency of cases in the HAL. Of the 46 patients with AIH, 16 (34.78%) were diagnosed with autoimmune rheumatic disease concurrence. Of these, 7 (15.22%) patients had Sjogren Ìs Disease (SD), 6 (13.04%) had systemic lupus erythematosus (SLE) and 3 (6.52%) had rheumatoid arthritis (RA). We found 39 patients with PBC, 18 (46.15%) had other associated extrahepatic autoimmune disease, of whom 12 (30.77%) had SD, 3 (7.69%) SLE and 3 (7.69%) RA. One patient had the diagnosis of PSC, a sixty year old woman that had no concurrence with rheumatic disease. In our study was found that SD is the most common rheumatic disease in patients with AIH and PBC, followed by SLE and RA, with autoimmune liver disease with rheumatic symptoms and vice versa.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gao, Jiaying; Liang, Biao; Zhang, Weizhao
In this work, a multiscale modeling framework for CFRP is introduced to study hierarchical structure of CFRP. Four distinct scales are defined: nanoscale, microscale, mesoscale, and macroscale. Information at lower scales can be passed to higher scale, which is beneficial for studying effect of constituents on macroscale part’s mechanical property. This bottom-up modeling approach enables better understanding of CFRP from finest details. Current study focuses on microscale and mesoscale. Representative volume element is used at microscale and mesoscale to model material’s properties. At microscale, unidirection CFRP (UD) RVE is used to study properties of UD. The UD RVE can bemore » modeled with different volumetric fraction to encounter non-uniform fiber distribution in CFRP part. Such consideration is important in modeling uncertainties at microscale level. Currently, we identified volumetric fraction as the only uncertainty parameters in UD RVE. To measure effective material properties of UD RVE, periodic boundary conditions (PBC) are applied to UD RVE to ensure convergence of obtained properties. Properties of UD is directly used at mesoscale woven RVE modeling, where each yarn is assumed to have same properties as UD. Within woven RVE, there can be many potential uncertainties parameters to consider for a physical modeling of CFRP. Currently, we will consider fiber misalignment within yarn and angle between wrap and weft yarns. PBC is applied to woven RVE to calculate its effective material properties. The effect of uncertainties are investigated quantitatively by Gaussian process. Preliminary results of UD and Woven study are analyzed for efficacy of the RVE modeling. This work is considered as the foundation for future multiscale modeling framework development for ICME project.« less
NASA Astrophysics Data System (ADS)
Vatsal, Manu; Devi, Vandna; Awasthi, Pamita
2018-04-01
The 1-[1-oxo-3-phenyl-(2-benzosulfonamide)-propyl amido] - anthracene-9,10-dione (BPAQ) an analogue of anthracenedione class of antibiotic has been synthesized. To characterize molecular functional groups FT-IR and FT-Raman spectrum were recorded and vibrational frequencies were assigned accordingly. The optimized geometrical parameters, vibrational assignments, chemical shifts and thermodynamic properties of title compound were computed by ab initio calculations at Density Functional Theory (DFT) method with 6-31G(d,p) as basis set. The calculated harmonic vibrational frequencies of molecule were then analysed in comparison to experimental FT-IR and Raman spectrum. Gauge independent atomic orbital (GIAO) method was used for determining, (1H) and carbon (13C) nuclear magnetic resonance (NMR) spectra of the molecule. Molecular parameters were calculated along with its periodic boundary conditions calculation (PBC) analysis supported by X-ray diffraction studies. The frontier molecular orbital (HOMO, LUMO) analysis describes charge distribution and stability of the molecule which concluded that nucleophilic substitution is more preferred and the mullikan charge analysis also confirmed the same. Further the title compound showed an inhibitory action at d(TCCCCC), an intermolecular i-motif sequence, hence molecular docking study suggested the inhibitory activity of the compound at these junction.
2012-01-01
Background Over half of kidney cancer survivors (KCS) are completely inactive and only a quarter are meeting physical activity (PA) guidelines. This highlights the need to identify and understand the determinants of PA in this understudied population. The purpose of this study is to determine the social cognitive correlates of PA intention and behavior in KCS using the Theory of Planned Behavior (TPB). Methods All 1,985 KCS diagnosed between 1996 and 2010 in Alberta, Canada were mailed a self-report survey that consisted of the Godin Leisure Time Exercise Questionnaire and standard TPB items for intention, planning, perceived behavioral control (PBC), affective and instrumental attitudes, and descriptive and injunctive norms. Standard demographic and medical variables were also collected. Results Completed surveys were received from 703 of 1,654 (43%) eligible KCS. The TPB was tested using structural equation modelling and demonstrated an adequate-to-good fit to the data [χ² = 256.88, p < .001; TLI = 0.97; CFI = 0.98; RMSEA = 0.06, 90% CI = 0.05-0.06]. There were significant pathways to PA from PBC (ß = 0.18, p = 0.02), planning (ß = 0.22, p < 0.01), and intention (ß = 0.31, p < 0.01); and to planning from intention (ß = 0.81, p < 0.01). In addition, there were significant model pathways to intention from instrumental attitude (ß = 0.28, p = 0.03), descriptive norm (ß = 0.09, p = 0.01), and PBC (ß = 0.52, p < 0.01). Overall, the TPB accounted for 69%, 63%, and 42% of the variance in intention, planning and PA, respectively. Conclusion The TPB appears to be a useful model for explaining PA in KCS. All TPB constructs except injunctive norm and affective attitude were useful for explaining intention with PBC emerging as the largest correlate. Developing PA interventions based on the TPB may be effective in promoting PA in KCS and may lead to important improvements in health. PMID:22866956
Webb, Travis P; Paul, Jasmeet; Treat, Robert; Codner, Panna; Anderson, Rebecca; Redlich, Philip
2014-01-01
A protected block curriculum (PBC) with postcurriculum examinations for all surgical residents has been provided to assure coverage of core curricular topics. Biannual assessment of resident competency will soon be required by the Next Accreditation System. To identify opportunities for early medical knowledge assessment and interventions, we examined whether performance in postcurriculum multiple-choice examinations (PCEs) is predictive of performance in the American Board of Surgery In-Training Examination (ABSITE) and clinical service competency assessments. Retrospective single-institutional education research study. Academic general surgery residency program. A total of 49 surgical residents. Data for PGY1 and PGY2 residents participating in the 2008 to 2012 PBC are included. Each resident completed 6 PCEs during each year. The results of 6 examinations were correlated to percentage-correct ABSITE scores and clinical assessments based on the 6 Accreditation Council for Graduate Medical Education core competencies. Individual ABSITE performance was compared between PGY1 and PGY2. Statistical analysis included multivariate linear regression and bivariate Pearson correlations. A total of 49 residents completed the PGY1 PBC and 36 completed the PGY2 curriculum. Linear regression analysis of percentage-correct ABSITE and PCE scores demonstrated a statistically significant correlation between the PGY1 PCE 1 score and the subsequent PGY1 ABSITE score (p = 0.037, β = 0.299). Similarly, the PGY2 PCE 1 score predicted performance in the PGY2 ABSITE (p = 0.015, β = 0.383). The ABSITE scores correlated between PGY1 and PGY2 with statistical significance, r = 0.675, p = 0.001. Performance on the 6 Accreditation Council for Graduate Medical Education core competencies correlated between PGY1 and PGY2, r = 0.729, p = 0.001, but did not correlate with PCE scores during either years. Within a mature PBC, early performance in a PGY1 and PGY2 PCE is predictive of performance in the respective ABSITE. This information can be used for formative assessment and early remediation of residents who are predicted to be at risk for poor performance in the ABSITE. Copyright © 2014 Association of Program Directors in Surgery. All rights reserved.
NASA Astrophysics Data System (ADS)
Regiec, Andrzej; Wojciechowski, Piotr; Pietraszko, Adam; Mączyński, Marcin
2018-06-01
Here, the Conductor-like Polarizable Continuum Model (CPCM) was used as a less demanding substitute of Periodic Boundary Conditions (PBC) method to attempt to reliably simulate infrared spectra and some structural parameters of solid compound - 5-amino-3-methyl-4-isoxazolecarbohydrazide (HIX). The measured relative electric permittivity of HIX was used as a simplified equivalent of electric intensity generating by other molecules of 5-amino-3-methyl-4-isoxazolecarbohydrazide in crystal structure. The application of CPCM has resulted in better conformity of calculated molecular parameters with experimentally found. Theoretical geometry was compared with data obtained with X-ray crystallography. Comparison of harmonic approximation with anharmonic one, based on the six selected characteristic vibrations, shows that non-scaled harmonic wavenumbers, calculated with CPCM, well correspond to experimental spectra. Additionally, the results point out that anharmonic approximation appeared to be strong sensitive for input geometry and calculation parameters used, so the results are sometimes unreliable, especially for low wavenumbers. Also, the new feasible ways of the synthesis of the titled compound is presented, one of which is particularly easy and highly efficient.
... PBC; a type of liver disease that destroys bile ducts, which allows bile to stay in the liver and cause damage) ... agonists. It works by decreasing the production of bile in the liver and increasing the removal of ...
Fellnhofer, Katharina
2017-01-01
Relying on Bandura's (1986) social learning theory, Ajzen's (1988) theory of planned behaviour (TPB), and Dyer's (1994) model of entrepreneurial careers, this study aims to highlight the potential of entrepreneurial role models to entrepreneurship education. The results suggest that entrepreneurial courses would greatly benefit from real-life experiences, either positive or negative. The results of regression analysis based on 426 individuals, primarily from Austria, Finland, and Greece, show that role models increase learners' entrepreneurial perceived behaviour control (PBC) by increasing their self-efficacy. This study can inform the research and business communities and governments about the importance of integrating entrepreneurs into education to stimulate entrepreneurial PBC. This study is the first of its kind using its approach, and its results warrant more in-depth studies of storytelling by entrepreneurial role models in the context of multimedia entrepreneurship education.
Cartier R, Luis; González L, Daniela; Harán D, Jorge
2015-11-01
The prevalence of drug-associated toxic encephalopathy is unknown, but it is an uncommon condition. Toxic leukoencephalopathy was described associated with heroin consumption, it has been less commonly described with the use of cocaine and there are no reports of its association with consumption pasta base of cocaine (PBC). We report two females aged 31 years and a male aged 19 years, consumers of PBC who developed a fatal toxic leukoencephalopathy. They initiated their disease with severe and persistent headache, sequential focal neurologic deficits and a progressive impairment of consciousness that culminated with their death. Laboratory parameters such as blood count, cerebrospinal fluid analyses or infectious biological indices were normal. MRI showed multifocal lesions in brain white matter of both hemispheres confirming the leukoencephalopathy. There was no response to the use of methylprednisolone.
Tidal Boundary Conditions in SEAWAT
Mulligan, Ann E.; Langevin, Christian; Post, Vincent E.A.
2011-01-01
SEAWAT, a U.S. Geological Survey groundwater flow and transport code, is increasingly used to model the effects of tidal motion on coastal aquifers. Different options are available to simulate tidal boundaries but no guidelines exist nor have comparisons been made to identify the most effective approach. We test seven methods to simulate a sloping beach and a tidal flat. The ocean is represented in one of the three ways: directly using a high hydraulic conductivity (high-K) zone and indirect simulation via specified head boundaries using either the General Head Boundary (GHB) or the new Periodic Boundary Condition (PBC) package. All beach models simulate similar water fluxes across the upland boundary and across the sediment-water interface although the ratio of intertidal to subtidal flow is different at low tide. Simulating a seepage face results in larger intertidal fluxes and influences near-shore heads and salinity. Major differences in flow occur in the tidal flat simulations. Because SEAWAT does not simulate unsaturated flow the water table only rises via flow through the saturated zone. This results in delayed propagation of the rising tidal signal inland. Inundation of the tidal flat is delayed as is flow into the aquifer across the flat. This is severe in the high-K and PBC models but mild in the GHB models. Results indicate that any of the tidal boundary options are fine if the ocean-aquifer interface is steep. However, as the slope of that interface decreases, the high-K and PBC approaches perform poorly and the GHB boundary is preferable.
Kanda, Tatsuo; Yasui, Shin; Nakamura, Masato; Nakamoto, Shingo; Takahashi, Koji; Wu, Shuang; Sasaki, Reina; Haga, Yuki; Ogasawara, Sadahisa; Saito, Tomoko; Kobayashi, Kazufumi; Kiyono, Soichiro; Ooka, Yoshihiko; Suzuki, Eiichiro; Chiba, Tetsuhiro; Maruyama, Hitoshi; Imazeki, Fumio; Moriyama, Mitsuhiko; Kato, Naoya
2018-02-20
Interferon-free treatment can achieve higher sustained virological response (SVR) rates, even in patients in whom hepatitis C virus (HCV) could not be eradicated in the interferon treatment era. Immune restoration in the liver is occasionally associated with HCV infection. We examined the safety and effects of interferon-free regimens on HCV patients with autoimmune liver diseases. All 7 HCV patients with autoimmune hepatitis (AIH) completed treatment and achieved SVR. Three patients took prednisolone (PSL) at baseline, and 3 did not take PSL during interferon-free treatment. In one HCV patient with AIH and cirrhosis, PSL were not administered at baseline, but she needed to take 40 mg/day PSL at week 8 for liver dysfunction. She also complained back pain and was diagnosed with vasospastic angina by coronary angiography at week 11. However, she completed interferon-free treatment. All 5 HCV patients with primary biliary cholangitis (PBC) completed treatment and achieved SVR. Three of these HCV patients with PBC were treated with UDCA during interferon-free treatment. Interferon-free regimens could result in higher SVR rates in HCV patients with autoimmune liver diseases. As interferon-free treatment for HCV may have an effect on hepatic immunity and activity of the autoimmune liver diseases, careful attention should be paid to unexpected adverse events in their treatments. Total 12 patients with HCV and autoimmune liver diseases [7 AIH and PBC], who were treated with interferon-free regimens, were retrospectively analyzed.
'We can't get anything done because...': making sense of 'barriers' to Practice-based Commissioning.
Checkland, Kath; Coleman, Anna; Harrison, Stephen; Hiroeh, Urara
2009-01-01
To investigate the issues raised by participants as 'barriers' to the development of Practice-based Commissioning (PBC) in 'early adopter' sites in England. Detailed case studies of five PBC consortia in three Primary Care Trusts (PCTs). Data collection included interviews with a wide range of respondents (46 in total), including general practitioners, PCT employees, Local Authority employees and patient representatives, observation of many different types of meetings (68 in total), and analysis of documents tabled at meetings and circulated at other times. It has been claimed that progress in developing PBC has been slow. Our respondents articulated a number of factors that they felt were holding them back, which could have been identified as 'barriers' preventing change. The issues raised were consistent across our sites (lack of time, resources and personnel, and difficult relationships with the PCT), but observation suggested that these issues arose out of very different organizational 'sensemaking', and as a result the apparent 'barriers' had different meanings in different organizational contexts. Weick's concept of 'organizational sensemaking' provides a useful framework within which to explore the problems encountered when implementing policy. Observational methods are a powerful tool in understanding sensemaking. The variations in sensemaking that we observed suggest that the use of 'barrier' metaphors in descriptions of implementation problems risks homogenizing the portrayal of situations that differ greatly in reality. This implies that top-down or centrally driven solutions to such situations will often be inappropriate.
Identification of HLA-A2–restricted CD8+ Cytotoxic T Cell Responses in Primary Biliary Cirrhosis
Kita, Hiroto; Lian, Zhe-Xiong; Van de Water, Judy; He, Xiao-Song; Matsumura, Shuji; Kaplan, Marshall; Luketic, Velimir; Coppel, Ross L.; Ansari, Aftab A.; Gershwin, M. Eric
2002-01-01
Primary biliary cirrhosis (PBC) is characterized by an intense biliary inflammatory CD4+ and CD8+ T cell response. Very limited information on autoantigen-specific cytotoxic T lymphocyte (CTL) responses is available compared with autoreactive CD4+ T cell responses. Using peripheral blood mononuclear cells (PBMCs) from PBC, we identified an HLA-A2–restricted CTL epitope of the E2 component of pyruvate dehydrogenase (PDC-E2), the immunodominant mitochondrial autoantigen. This peptide, amino acids 159–167 of PDC-E2, induces specific MHC class I–restricted CD8+ CTL lines from 10/12 HLA-A2+ PBC patients, but not controls, after in vitro stimulation with antigen-pulsed dendritic cells (DCs). PDC-E2–specific CTLs could also be generated by pulsing DCs with full-length recombinant PDC-E2 protein. Furthermore, using soluble PDC-E2 complexed with either PDC-E2–specific human monoclonal antibody or affinity-purified autoantibodies against PDC-E2, the generation of PDC-E2–specific CTLs, occurred at 100-fold and 10-fold less concentration, respectively, compared with soluble antigen alone. Collectively, these data demonstrate that autoantibody, helper, and CTL epitopes all contain a shared peptide sequence. The finding that autoantigen–immune complexes can not only cross-present but also that presentation of the autoantigen is of a higher relative efficiency, for the first time defines a unique role for autoantibodies in the pathogenesis of an autoimmune disease. PMID:11781370
Haslemo, Tore; Refsum, Helge; Molden, Espen
2011-04-01
To investigate the potential interaction between olanzapine, a CYP1A2 substrate, and ethinylestradiol-containing contraceptives (ECC). The study was carried out at a routine therapeutic drug monitoring service. To identify patients who were co-administered ECC or other contraceptives, a questionnaire was sent to the physician who ordered serum monitoring of olanzapine for women aged 18-40 years during an 18 month period. The physicians were asked to provide information about contraceptive use and smoking habits. When questionnaires were returned by the physicians, the respective serum concentration data were included in the analysis. Patients were stratified into users of ECC, progestogen-based contraceptives (PBC) or no contraceptives. Dose-adjusted serum concentrations of olanzapine and the metabolite N-desmethyl olanzapine were compared between the subgroups. A total of 149 patients were included in the study (10 ECC users and 10 PBC users). In users of ECC, we found no differences in serum concentrations of olanzapine, but significantly lower concentrations of the CYP1A2-mediated metabolite N-desmethyl olanzapine compared with users of PBC (P = 0.019) and non-contraceptive users (P = 0.012). The present study confirms that ECC exhibit CYP1A2-inhibitory properties in terms of significantly lower exposure of N-desmethyl olanzapine. However, the inhibition does not provide clinically relevant changes in serum concentrations of olanzapine. © 2011 The Authors. British Journal of Clinical Pharmacology © 2011 The British Pharmacological Society.
Honda, Kosuke; Natsumi, Yoshiko; Urade, Masahiro
2008-12-01
The relationship of bony changes in the condylar surfaces in articular disc displacement without reduction in temporomandibular joint (TMJ) was investigated using diagnostic imaging. The study also evaluated whether the bony changes in the condylar surfaces limit disc and condyle motion, and produce pathological joint sounds. Thirty-seven joints in 28 patients diagnosed with degenerative bony changes in the condylar surfaces radiographically and anterior disc displacement without reduction using magnetic resonance imaging (MRI) were studied. The bony changes were assessed by radiographic examination and classified into two types: pathological bone changes (PBCs) including erosion, osteophyte formation and deformity, and adaptive bone changes (ABCs) including flattening and concavity. MRI was performed on the TMJ to examine the configuration and position of the discs. Joint sounds in the TMJ were determined using electrovibratograghy with a joint vibration analysis. The articular disc motion to the condyle in the PBC group was smaller than in the ABC group irrespective of the configuration of the disc, even though there were no significant differences between the two types of bony changes in the disc position during jaw closing. The joint vibration analysis of the TMJ showed that joint sounds with a higher frequency were observed in the PBC group than in the ABC group. High energy levels needed to produce the higher frequencies (over 300 Hz) were observed only in the PBC group.
Yan, Xin; Jin, Jinglan
2018-01-01
Abstract Rationale: Primary cutaneous amyloidosis (PCA) is a localized skin disorder characterized by the abnormal deposition of amyloid in the extracellular matrix of the dermis. The association between PCA and other diseases, although rare, has been documented for various autoimmune diseases. PCA associated with autoimmune hepatitis-primary biliary cirrhosis (AIH-PBC) overlap syndrome and Sjögren syndrome (SS) has not been previously reported in the literature. Patient concerns: A 50-year-old woman presented with progressive abnormal liver enzyme levels and was referred to our department. Diagnoses: Due to the patient's symptoms, laboratory test results, radiographic findings, and pathologic results, she was diagnosed with PCA associated with AIH-PBC overlap syndrome and SS. Interventions: She was subsequently treated with a combination of ursodeoxycholic acid (UDCA), prednisone, and azathioprine. Outcomes: While this treatment can achieve therapeutic success, it cannot prevent complications from cirrhosis. This patient remains alive but experienced an emergent gastrointestinal hemorrhage. Lessons: While we acknowledge that this is a single case, these findings extend our knowledge of immunological diseases associated with PCA and suggest a common, immune-mediated pathogenic pathway between PCA, AIH-PBC overlap syndrome, and SS. After 12 years of follow up, clinical manifestations have developed, and these autoimmune diseases have progressed. The combination of UDCA, prednisone, and azathioprine can achieve therapeutic success but cannot prevent disease progression. Routine follow up for this patient is necessary to document disease progression. PMID:29465536
Chen, Wen-Jing; Ye, Jing-Ying; Li, Xin; Xu, Jia; Yi, Hai-Jin
2017-08-23
This study aims to discuss clinical characteristics, image manifestation and treatment methods of temporal bone lesions with facial paralysis as the main manifestation for deepening the understanding of such type of lesions and reducing erroneous and missed diagnosis. The clinical data of 16 patients with temporal bone lesions and facial paralysis as main manifestation, who were diagnosed and treated from 2009 to 2016, were retrospectively analyzed. Among these patients, six patients had congenital petrous bone cholesteatoma (PBC), nine patients had facial nerve schwannoma, and one patient had facial nerve hemangioma. All the patients had an experience of long-term erroneous diagnosis. The lesions were completely excised by surgery. PBC and primary facial nerve tumors were pathologically confirmed. Facial-hypoglossal nerve anastomosis was performed on two patients. HB grade VI was recovered to HB grade V in one patient. The anastomosis failed due to severe facial nerve fibrosis in one patient. Hence, HB remained at grade VI. Postoperative recovery was good for all patients. No lesion recurrence was observed after 1-6 years of follow-up. For the patients with progressive or complete facial paralysis, imaging examination should be perfected in a timely manner. Furthermore, PBC, primary facial nerve tumors and other temporal bone space-occupying lesions should be eliminated. Lesions should be timely detected and proper intervention should be conducted, in order to reduce operation difficulty and complications, and increase the opportunity of facial nerve function reconstruction.
Cheng, Chien-Mu; Huang, Jiun-Hau
2017-10-27
This study examined condom use intentions among adolescent boys in relation to the constructs of the Theory of Planned Behavior (TPB): attitude toward the behavior (ATB), subjective norm (SN), and perceived behavioral control (PBC). The potential moderating effects of sexual orientation and gender characteristic (masculine/feminine) were also explored. Anonymous survey data were collected from 929 students enrolled in a boys' senior high school in Taiwan (response rate: 89.9%). Multivariate logistic regression analyses found higher condom use intentions linked to more positive ATB (adjusted odds ratio [AOR] = 8.09) and supportive SN (AOR = 2.73), as well as high PBC under facilitating conditions (AOR = 2.04). Notably, nonheterosexual boys perceiving supportive SN (AOR = 0.23) or high support for condom use from teachers and health educators (AOR = 0.10 and 0.26, respectively) had lower condom use intentions than their heterosexual peers. By contrast, relatively feminine boys perceiving supportive SN (AOR = 2.06) or high support from close friends (AOR = 2.18) had higher condom use intentions than their masculine counterparts. In conclusion, ATB and SN were strongly linked to condom use intentions; PBC was significant only under facilitating conditions. Sexual orientation and gender characteristic had important moderating effects. These empirical findings could inform tailored health education programs to increase condom use intentions in the male student population.
Besachio, David A; Khaleel, Ziyad; Shah, Lubdha M
2015-12-01
Posterior odontoid process inclination has been demonstrated as a factor associated with Chiari malformation Type I (CM-I) in the pediatric population; however, no studies to date have examined this measurement in the adult CM-I population. The purpose of this study was to evaluate craniocervical junction (CCJ) measurements in adult CM-I versus a control group. The odontoid retroflexion, odontoid retroversion, odontoid height, posterior basion to C-2 line measured to the dural margin (pB-C2 line), posterior basion to C-2 line measured to the dorsal odontoid cortical margin (pB-C2* line), and clivus-canal angle measurements were retrospectively analyzed in adult patients with CM-I using MRI. These measurements were compared with normative values established from CT scans of the cervical spine in adults without CM-I. A statistically significant difference was found between 55 adults with CM-I and 150 sex-matched controls (125 used for analysis) in the mean clivus-canal angle and the mean pB-C2 line. These data suggest that there are sex-specific differences with respect to measurements at the CCJ between men and women, with women showing a more posteriorly inclined odontoid process. There were also differences between the CM-I and control groups: a more acute clivus-canal angle was associated with CM-I in the adult population. These CCJ findings could have an influence on presurgical planning.
Mesodermal expression of the C. elegans HMX homolog mls-2 requires the PBC homolog CEH-20
Jiang, Yuan; Shi, Herong; Amin, Nirav M.; Sultan, Ibrahim; Liu, Jun
2008-01-01
Metazoan development proceeds primarily through the regulated expression of genes encoding transcription factors and components of cell signaling pathways. One way to decipher the complex developmental programs is to assemble the underlying gene regulatory networks by dissecting the cis-regulatory modules that direct temporal-spatial expression of developmental genes and identify corresponding trans-regulatory factors. Here, we focus on the regulation of a HMX homoebox gene called mls-2, which functions at the intersection of a network that regulates cleavage orientation, cell proliferation and fate specification in the C. elegans postembryonic mesoderm. In addition to its transient expression in the postembryonic mesodermal lineage, the M lineage, mls-2 expression is detected in a subset of embryonic cells, in three pairs of head neurons and transiently in the somatic gonad. Through mutational analysis of the mls-2 promoter, we identified two elements (E1 and E2) involved in regulating the temporal-spatial expression of mls-2. In particular, we showed that one of the elements (E1) required for mls-2 expression in the M lineage contains two critical putative PBC-Hox binding sites that are evolutionarily conserved in C. briggsae and C. remanei. Furthermore, the C. elegans PBC homolog CEH-20 is required for mls-2 expression in the M lineage. Our data suggests that mls-2 might be a direct target of CEH-20 in the M lineage and that the regulation of CEH-20 on mls-2 is likely Hox-independent. PMID:18316179
Impact of radiation attenuation by a carbon fiber couch on patient dose verification
NASA Astrophysics Data System (ADS)
Yu, Chun-Yen; Chou, Wen-Tsae; Liao, Yi-Jen; Lee, Jeng-Hung; Liang, Ji-An; Hsu, Shih-Ming
2017-02-01
The aim of this study was to understand the difference between the measured and calculated irradiation attenuations obtained using two algorithms and to identify the influence of couch attenuation on patient dose verification. We performed eight tests of couch attenuation with two photon energies, two longitudinal couch positions, and two rail positions. The couch attenuation was determined using a radiation treatment planning system. The measured and calculated attenuations were compared. We also performed 12 verifications of head-and-neck and rectum cases by using a Delta phantom. The dose deviation (DD), distance to agreement (DTA), and gamma index of pencil-beam convolution (PBC) verifications were nearly the same. The agreement was least consistent for the anisotropic analytical algorithm (AAA) without the couch for the head-and-neck case, in which the DD, DTA, and gamma index were 74.4%, 99.3%, and 89%, respectively; for the rectum case, the corresponding values were 56.2%, 95.1%, and 92.4%. We suggest that dose verification should be performed using the following three metrics simultaneously: DD, DTA, and the gamma index.
Autoimmune hepatitis in a teenage boy: 'overlap' or 'outlier' syndrome--dilemma for internists.
Talukdar, Arunansu; Khanra, Dibbendhu; Mukherjee, Kabita; Saha, Manjari
2013-02-08
An 18-year-old boy presented with upper gastrointestinal bleeding and jaundice. Investigations revealed coarse hepatomegaly, splenomegaly and advanced oesophageal varices. Blood reports showed marked rise of alkaline phosphatase and more than twofold rise of transaminases and IgG. Liver histology was suggestive of piecemeal necrosis, interphase hepatitis and bile duct proliferation. Antinuclear antibody was positive in high titre along with positive antismooth muscle antibody and antimitochondrial antibody. The patient was positive for human leukocyte antigen DR3 type. Although an 'overlap' syndrome exists between autoimmune hepatitis (AIH) and primary biliary cirrhosis (PBC), a cholestatic variant of AIH, a rare 'outlier' syndrome could not be excluded in our case. Moreover, 'the chicken or the egg', AIH or PBC, the dilemma for the internists continued. The patient was put on steroid and ursodeoxycholic acid with unsatisfactory response. The existing international criteria for diagnosis of AIH are not generous enough to accommodate its variant forms.
Fellnhofer, Katharina
2017-01-01
Relying on Bandura’s (1986) social learning theory, Ajzen’s (1988) theory of planned behaviour (TPB), and Dyer’s (1994) model of entrepreneurial careers, this study aims to highlight the potential of entrepreneurial role models to entrepreneurship education. The results suggest that entrepreneurial courses would greatly benefit from real-life experiences, either positive or negative. The results of regression analysis based on 426 individuals, primarily from Austria, Finland, and Greece, show that role models increase learners’ entrepreneurial perceived behaviour control (PBC) by increasing their self-efficacy. This study can inform the research and business communities and governments about the importance of integrating entrepreneurs into education to stimulate entrepreneurial PBC. This study is the first of its kind using its approach, and its results warrant more in-depth studies of storytelling by entrepreneurial role models in the context of multimedia entrepreneurship education. PMID:29104604
Afroz, Rafia; Masud, Muhammad Mehedi; Akhtar, Rulia; Islam, Md Ashraful; Duasa, Jarita Bt
2015-10-01
This paper examines whether attitudes towards electric vehicles (ATEVs), subjective norms (SNs) and perceived behavioural control (PBC) have significant associations with consumer purchase intention (PI) and the purchase behaviour of environmentally friendly vehicles (EFVs). The results from the survey questionnaires are analysed using confirmatory factor analysis (CFA) and structural equation modelling (SEM). The findings of this paper indicate that ATEV, SN and PBC significantly influence PI. This finding also indicates that environmental consequence and individual preferences do not influence the PI of the respondents. We found that Malaysian car owners are largely unaware of the greenhouse effects on the environment or attach to it little importance, which is reflected in their PI towards EFVs. The outcomes of this study could help policymakers design programmes to influence attitudes, subjective norms, perceived behavioural control and purchase behaviour to prevent further air pollution and reduce CO2 emissions from the transportation sector.
Ma, Hong; Zeng, Minde; Han, Ying; Yan, Huiping; Tang, Hong; Sheng, Jifang; Hu, Heping; Cheng, Liufang; Xie, Qing; Zhu, Youfu; Chen, Guofeng; Gao, Zhiliang; Xie, Wen; Wang, Jiyao; Wu, Shanming; Wang, Guiqiang; Miao, Xiaohui; Fu, Xiaoqing; Duan, Liping; Xu, Jie; Wei, Lai; Shi, Guangfeng; Chen, Chengwei; Chen, Minhu; Ning, Qin; Yao, Chen; Jia, Jidong
2016-01-01
Abstract Aim: Tauroursodeoxycholic acid (TUDCA) is a taurine conjugated form of ursodeoxycholic acid (UDCA) with higher hydrophility. To further evaluate the efficacy and safety of TUDCA for primary biliary cholangitis (PBC), we performed this study on Chinese patients. Methods: 199 PBC patients were randomly assigned to either 250 mg TUDCA plus UDCA placebo or 250 mg UDCA plus TUDCA placebo, 3 times per day for 24 weeks. The primary endpoint was defined as percentage of patients achieving serum alkaline phosphatase (ALP) reduction of more than 25% from baseline. Results: At week 24, 75.97% of patients in the TUDCA group and 80.88% of patients in the UDCA group achieved a serum ALP reduction of more than 25% from baseline (P = 0.453). The percentage of patients with serum ALP levels declined more than 40% following 24 weeks of treatment was 55.81% in the TUDCA group and 52.94% in the UDCA group (P = 0.699). Both groups showed similar improvement in serum levels of ALP, aspartate aminotransferase, and total bilirubin (P > 0.05). The proportion of patients with pruritus/scratch increased from 1.43% to 10.00% in UDCA group, while there's no change in TUDCA group (P = 0.023). Both drugs were well tolerated, with comparable adverse event rates between the 2 groups. Conclusions: TUDCA is safe and as efficacious as UDCA for the treatment of PBC, and may be better to relieve symptoms than UDCA. PMID:27893675
Kanda, Tatsuo; Yasui, Shin; Nakamura, Masato; Nakamoto, Shingo; Takahashi, Koji; Wu, Shuang; Sasaki, Reina; Haga, Yuki; Ogasawara, Sadahisa; Saito, Tomoko; Kobayashi, Kazufumi; Kiyono, Soichiro; Ooka, Yoshihiko; Suzuki, Eiichiro; Chiba, Tetsuhiro; Maruyama, Hitoshi; Imazeki, Fumio; Moriyama, Mitsuhiko; Kato, Naoya
2018-01-01
Background Interferon-free treatment can achieve higher sustained virological response (SVR) rates, even in patients in whom hepatitis C virus (HCV) could not be eradicated in the interferon treatment era. Immune restoration in the liver is occasionally associated with HCV infection. We examined the safety and effects of interferon-free regimens on HCV patients with autoimmune liver diseases. Results All 7 HCV patients with autoimmune hepatitis (AIH) completed treatment and achieved SVR. Three patients took prednisolone (PSL) at baseline, and 3 did not take PSL during interferon-free treatment. In one HCV patient with AIH and cirrhosis, PSL were not administered at baseline, but she needed to take 40 mg/day PSL at week 8 for liver dysfunction. She also complained back pain and was diagnosed with vasospastic angina by coronary angiography at week 11. However, she completed interferon-free treatment. All 5 HCV patients with primary biliary cholangitis (PBC) completed treatment and achieved SVR. Three of these HCV patients with PBC were treated with UDCA during interferon-free treatment. Conclusions Interferon-free regimens could result in higher SVR rates in HCV patients with autoimmune liver diseases. As interferon-free treatment for HCV may have an effect on hepatic immunity and activity of the autoimmune liver diseases, careful attention should be paid to unexpected adverse events in their treatments. Methods Total 12 patients with HCV and autoimmune liver diseases [7 AIH and PBC], who were treated with interferon-free regimens, were retrospectively analyzed. PMID:29545925
Effects of coating materials on nanoindentation hardness of enamel and adjacent areas.
Alsayed, Ehab Z; Hariri, Ilnaz; Nakashima, Syozi; Shimada, Yasushi; Bakhsh, Turki A; Tagami, Junji; Sadr, Alireza
2016-06-01
Materials that can be applied as thin coatings and actively release fluoride or other bioavailable ions for reinforcing dental hard tissue deserve further investigation. In this study we assessed the potential of resin coating materials in protection of underlying and adjacent enamel against demineralization challenge using nanoindentation. Enamel was coated using Giomer (PRG Barrier Coat, PBC), resin-modified glass-ionomer (Clinpro XT Varnish, CXT), two-step self-etch adhesive (Clearfil SE Protect, SEP) or no coating (control). After 5000 thermal cycles and one-week demineralization challenge, Martens hardness of enamel beneath the coating, uncoated area and intermediate areas was measured using a Berkovich tip under 2mN load up to 200μm depth. Integrated hardness and 10-μm surface zone hardness were compared among groups. Nanoindentation and scanning electron microscopy suggested that all materials effectively prevented demineralization in coated area. Uncoated areas presented different hardness trends; PBC showed a remarkable peak at the surface zone before reaching as low as the control, while CXT showed relatively high hardness values at all depths. Ion-release from coating materials affects different layers of enamel. Coatings with fluoride-releasing glass fillers contributed to reinforcement of adjacent enamel. Surface prereacted glass filler-containing PBC superficially protected neighboring enamel against demineralization, while resin-modified glass-ionomer with calcium (CXT) improved in-depth protection. Cross-sectional hardness mapping of enamel on a wide range of locations revealed minute differences in its structure. Copyright © 2016 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
Milton, Alyssa C; Mullan, Barbara A
2012-03-01
Approximately 48 million Americans are affected by foodborne illness each year. Evidence suggests that the application of health psychology theory to food safety interventions can increase behaviors that reduce the incidence of illness such as adequately keeping hands, surfaces and equipment clean. This aim of this pilot study was to be the first to explore the effectiveness of a food safety intervention based on the Theory of Planned Behavior (TPB). Young adult participants (N = 45) were randomly allocated to intervention, general control or mere measurement control conditions. Food safety observations and TPB measures were taken at baseline and at 4-week follow-up. Within and between group differences on target variables were considered and regression analyses were conducted to determine the relationship between condition, behavior and the TPB intention constructs; attitude, subjective norm, perceived behavioral control (PBC). TPB variables at baseline predicted observed food safety behaviors. At follow-up, the intervention led to significant increases in PBC (p = .024) and observed behaviors (p = .001) compared to both control conditions. Furthermore, correlations were found between observed and self-reported behaviors (p = .008). The pilot intervention supports the utility of the TPB as a method of improving food safety behavior. Changes in TPB cognitions appear to be best translated to behavior via behavioral intentions and PBC. Further research should be conducted to increase effectiveness of translating TPB variables to food safety behaviors. The additional finding of a correlation between self-reported and observed behavior also has implications for future research as it provides evidence toward the construct validity of self-reported behavioral measures.
Results of Percutaneous Balloon Compression in Trigeminal Pain Syndromes.
Grewal, Sanjeet S; Kerezoudis, Panagiotis; Garcia, Oscar; Quinones-Hinojosa, Alfredo; Reimer, Ronald; Wharen, Robert E
2018-06-01
To investigate initial pain relief and subsequent recurrence after percutaneous balloon compression (PBC) and describe its association with the nature of trigeminal pain, previous procedures, or other clinical factors. A total of 222 patients with medically refractory trigeminal pain treated with PBC at Mayo Clinic Florida between 1998 and 2017 were enrolled into this study. Patients were divided into those with typical trigeminal neuralgia (TN) and those with atypical trigeminal pain. The postprocedural rate of pain recurrence and associations between patient characteristics and recurrence were studied. One hundred fifty-two patients had TN and 70 patients had atypical pain. At the last follow-up, 158 patients had excellent pain relief, 37 had good pain relief, 11 had fair pain relief, and 16 had poor pain relief. The median duration of follow-up was 31.1 months. Patients with atypical pain were less likely to have an excellent result compared with patients with typical pain (61.4% vs. 82.9%; P < 0.001). Recurrence was observed in 103 patients (46.4%) and was associated with previous procedures (hazard ratio, 1.658; 95% confidence interval, 1.09-2.49; P = 0.017). Other clinical factors were not significant. Our study demonstrates the safety and efficacy of PBC, with 88% of patients pain-free at last follow-up. Patients with atypical pain have worse outcomes, and patients with previous procedures have a higher risk of recurrence. Repeat surgery does not decrease efficacy. We recommend conservative parameter selection at the initial procedure. Copyright © 2018 Elsevier Inc. All rights reserved.
Walsh, Anne M; Hamilton, Kyra; White, Katherine M; Hyde, Melissa K
2015-04-02
The use of the internet to access information is rapidly increasing; however, the quality of health information provided on various online sites is questionable. We aimed to examine the underlying factors that guide parents' decisions to use online information to manage their child's health care, a behaviour which has not yet been explored systematically. Parents (N = 391) completed a questionnaire assessing the standard theory of planned behaviour (TPB) measures of attitude, subjective norm, perceived behavioural control (PBC), and intention as well as the underlying TPB belief-based items (i.e., behavioural, normative, and control beliefs) in addition to a measure of perceived risk and demographic variables. Two months later, consenting parents completed a follow-up telephone questionnaire which assessed the decisions they had made regarding their use of online information to manage their child's health care during the previous 2 months. We found support for the TPB constructs of attitude, subjective norm, and PBC as well as the additional construct of perceived risk in predicting parents' intentions to use online information to manage their child's health care, with further support found for intentions, but not PBC, in predicting parents' behaviour. The results of the TPB belief-based analyses also revealed important information about the critical beliefs that guide parents' decisions to engage in this child health management behaviour. This theory-based investigation to understand parents' motivations and online information-seeking behaviour is key to developing recommendations and policies to guide more appropriate help-seeking actions among parents.
Gavaza, Paul; Fleming, Marc; Barner, Jamie C
2014-01-01
Little is known about the main drivers of pharmacists' intention to utilize prescription drug monitoring programs (PDMPs) when making care decisions and the actual contribution of these factors in explaining intention and behavior. This study examined what theory of planned behavior (TPB) model constructs (i.e., attitude, subjective norm [SN], perceived behavioral control [PBC]), past utilization behavior (PUB) and perceived moral obligation (PMO) were significant predictors of Virginia community pharmacists' intention to utilize a PDMP. A cover letter with a link to a 28-item online survey was e-mailed to 600 members of the Virginia Pharmacists Association. Multiple regression analyses were used to determine the association between pharmacists' intention to utilize the PDMP database and attitude, SN, PBC, PUB and PMO. Ninety-seven usable responses were received, for a response rate of 16.2%. A majority of the respondents were Caucasian (96.4%), female (50.5%), working in independent community pharmacies (60.4%) with an average age of 49.5 ± 13.4 years. Overall, pharmacists intended to utilize a PDMP (mean = 5.3 ± 4.6; possible range: -9 to 9), had a positive attitude toward utilizing PDMP (mean = 6.3 ± 5.3; possible range: -12 to 12), perceived that others wanted them to utilize a PDMP (SN score = 3.7 ± 2.4; range: -6 to 6), and believed that they had control over utilization behavior (PBC score = 4.5 ± 4.0; range: -9 to 9). Attitude (β = 0.723, P < 0.001), SN (β = 0.230, P = 0.014) and PBC (β = -0.215, P = 0.026) significantly predicted pharmacists' intent, accounting for 56.7% of the variance in intention to utilize the PDMP database (P < 0.001). The addition of PMO (P < 0.001) significantly contributed to explaining the variance in intention but PUB did not. Members of the Virginia Pharmacists Association who responded to the survey showed a strong positive intent to utilize PDMP database. Pharmacists' attitudes, subjective norm, perceived behavioral control and perceived moral obligation were significant predictors of intention but past utilization behavior was not. The TPB is a useful theoretical framework when predicting PDMP utilization behavior of community pharmacists, accounting for 56.7% of the variance in intention. Copyright © 2014 Elsevier Inc. All rights reserved.
Tajeddine, Ayman; Kayssi, Ayman; Chehab, Ali; Elhajj, Imad; Itani, Wassim
2015-01-01
In this paper, we present CENTERA, a CENtralized Trust-based Efficient Routing protocol with an appropriate authentication scheme for wireless sensor networks (WSN). CENTERA utilizes the more powerful base station (BS) to gather minimal neighbor trust information from nodes and calculate the best routes after isolating different types of “bad” nodes. By periodically accumulating these simple local observations and approximating the nodes' battery lives, the BS draws a global view of the network, calculates three quality metrics—maliciousness, cooperation, and compatibility—and evaluates the Data Trust and Forwarding Trust values of each node. Based on these metrics, the BS isolates “bad”, “misbehaving” or malicious nodes for a certain period, and put some nodes on probation. CENTERA increases the node's bad/probation level with repeated “bad” behavior, and decreases it otherwise. Then it uses a very efficient method to distribute the routing information to “good” nodes. Based on its target environment, and if required, CENTERA uses an authentication scheme suitable for severely constrained nodes, ranging from the symmetric RC5 for safe environments under close administration, to pairing-based cryptography (PBC) for hostile environments with a strong attacker model. We simulate CENTERA using TOSSIM and verify its correctness and show some energy calculations. PMID:25648712
Tajeddine, Ayman; Kayssi, Ayman; Chehab, Ali; Elhajj, Imad; Itani, Wassim
2015-02-02
In this paper, we present CENTERA, a CENtralized Trust-based Efficient Routing protocol with an appropriate authentication scheme for wireless sensor networks (WSN). CENTERA utilizes the more powerful base station (BS) to gather minimal neighbor trust information from nodes and calculate the best routes after isolating different types of "bad" nodes. By periodically accumulating these simple local observations and approximating the nodes' battery lives, the BS draws a global view of the network, calculates three quality metrics-maliciousness, cooperation, and compatibility-and evaluates the Data Trust and Forwarding Trust values of each node. Based on these metrics, the BS isolates "bad", "misbehaving" or malicious nodes for a certain period, and put some nodes on probation. CENTERA increases the node's bad/probation level with repeated "bad" behavior, and decreases it otherwise. Then it uses a very efficient method to distribute the routing information to "good" nodes. Based on its target environment, and if required, CENTERA uses an authentication scheme suitable for severely constrained nodes, ranging from the symmetric RC5 for safe environments under close administration, to pairing-based cryptography (PBC) for hostile environments with a strong attacker model. We simulate CENTERA using TOSSIM and verify its correctness and show some energy calculations.
Locomotive Crash Energy Management Coupling Tests
DOT National Transportation Integrated Search
2018-04-18
This paper describes the results of the CEM equipped locomotive coupling tests. In this set of tests, a moving CEM locomotive was coupled to a standing cab car. The primary objective was to demonstrate the robustness of the PBC design and determine t...
Ter Borg, Evert-Jan; Kelder, Johannes Cornelis
2017-07-01
To test the hypothesis that systemic auto-antibodies or hypergammaglobulinemia are related to the prevalence of extra-glandular tissue organ damage (EGOD) in primary Sjögren's syndrome (SS). A real practice-based investigation of a relatively large (n = 110) Dutch cohort of primary SS patients systematically followed up in a large non-academic hospital. After a follow up of mean 8.2 years a significant correlation was found between disease duration and the prevalence of EGOD. We did not observe a relationship between the total number or type of systemic auto-antibodies or hypergammaglobulinemia and the total number of EGOD. However, there was a correlation between the prevalence of polyneuropathy (PNP) and antinuclear antibodies (ANA) as well as anti-Ro/SS-A positivity and there was an inverse relationship between the presence of anti-Ro/SS-A antibodies and primary biliary cirrhosis (PBC). All PBC cases were anti-Ro/SS-A and anti-La/SS-B negative but ANA positive. There was a trend for a higher occurrence of pleuro-pulmonary disease in the ANA negative cases. Although we did not find a relationship between the total number or type of systemic auto-antibodies and the total number of EGOD, there were correlations between specific systemic auto-antibodies and specific types of EGOD. The presence of ANA and anti-Ro/SS-A was associated with the occurrence of PNP, as well as was the absence of anti-Ro/SS-A with PBC. © 2017 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd.
Lammert, Craig; Juran, Brian D.; Schlicht, Erik; Chan, Landon L.; Atkinson, Elizabeth J.; de Andrade, Mariza; Lazaridis, Konstantinos N.
2014-01-01
Background Biochemical response to Ursodeoxycholic Acid among patients with Primary Biliary Cirrhosis remains variable and there is no agreement of an ideal model. Novel assessment of response coupled to histologic progression was recently defined by the Toronto criteria. We retrospectively assessed transplant-free survival and clinical outcomes associated with Ursodeoxycholic Acid response to evaluate the Toronto criteria using a large North American cohort of PBC patients. Methods 398 PBC patients from the Mayo Clinic PBC Genetic Epidemiology (MCPGE) Registry were assessed for Ursodeoxycholic Acid treatment and biochemical response per the Toronto criteria. Responders were defined by reduction in alkaline phosphatase to less than or equal to 1.67 times the upper normal limit by 2 years of treatment, whereas non-responders had alkaline phosphatase values greater than 1.67 times the upper normal limit. Probability of survival was estimated using the Kaplan-Meier method. Results 302 (76%) patients were responders and 96 (24%) were non-responders. Significantly more non-responders developed adverse events related to chronic liver disease compared to responders (Hazard Ratio (HR): 2.77, P = 0.001). Biochemical responders and early-stage disease at treatment start was associated with improved overall transplant-free survival compared to non-responders (HR: 1.9) and patients with late stage disease (HR: 2.7) after age and sex adjustment. Conclusions The Toronto criteria are capable of identifying Ursodeoxycholic Acid-treated Primary Biliary Cirrhosis patients at risk of poor transplant-free survival and adverse clinical outcomes. Our data reveal that despite advanced disease at diagnosis, biochemical response per the Toronto criteria associates with improved overall transplant-free survival. PMID:24317935
Cheung, A C; Lapointe-Shaw, L; Kowgier, M; Meza-Cardona, J; Hirschfield, G M; Janssen, H L A; Feld, J J
2016-01-01
Fibrates appear to improve biochemistry in patients with primary biliary cholangitis (PBC), but it is unclear which factors predict response and whether treatment improves transplant-free survival. To evaluate biochemical profiles, liver-related outcomes and adverse events following fenofibrate therapy in PBC patients with incomplete response to ursodeoxycholic acid (UDCA). A retrospective cohort study was performed at a tertiary centre. Cox regression was used to compare outcomes between patients treated with fibrates and UDCA (FF) or UDCA alone, adjusted for a propensity score to account for treatment selection bias. A total of 120 patients were included (FF group n = 46, UDCA group n = 74, median fenofibrate treatment 11 months); 41% vs. 7% met the Toronto criteria for biochemical response [alkaline phosphatase ≤1.67 times the upper limit of normal] in the FF and UDCA groups, respectively (P = 0.0001). Fenofibrate was also associated with improved decompensation-free and transplant-free survival [hazard ratio (HR) 0.09, 95% CI 0.03-0.32, P = 0.0002]. However, only fenofibrate use, not biochemical response, was independently associated with improved outcomes on multivariable analysis (HR 0.40, 95% CI 0.17-0.93, P = 0.03). Twenty-two percent discontinued fenofibrate due to adverse events (most common: abdominal pain and myalgias). In cirrhotic patients, bilirubin increased more rapidly in the FF group (P = 0.005). Fenofibrate therapy is associated with significant improvement in alkaline phosphatase, decompensation-free and transplant-free survival in PBC patients with incomplete UDCA response. However, fenofibrate should be used cautiously in cirrhosis, with close monitoring for clinical/biochemical decompensation. Additional studies are required to assess the validity of alkaline phosphatase as an appropriate response criteria for fibrate therapy. © 2015 John Wiley & Sons Ltd.
Hagger, Martin S; Lonsdale, Adam J; Hein, Vello; Koka, Andre; Lintunen, Taru; Pasi, Heidi; Lindwall, Magnus; Rudolfsson, Lisa; Chatzisarantis, Nikos L D
2012-05-01
This study tested an integrated model of the psychosocial determinants of alcohol-related behaviour among company employees from four nations. A motivational sequence was proposed in which motivational orientations from self-determination theory influenced intentions to consume alcohol within guideline limits and alcohol-related behaviour via the mediation of the theory of planned behaviour variables of attitude, subjective norms, and perceived behavioural control (PBC). A three-wave prospective design using self-reported psychological and behavioural measures. Company employees (N= 486, males = 225, females = 261; M age = 30.41, SD= 8.31) from four nations (Estonia, Finland, Sweden, and UK) completed measures of autonomous and controlled motivation from self-determination theory, attitudes, subjective norms, PBC, intentions from the theory of planned behaviour, and self-reported measures of past alcohol consumption and binge-drinking occasions at the first time point (time 1). Follow-up psychological and behavioural measures were taken one month later (time 2) and follow-up behavioural measures taken a further 2 months later (time 3). Path analyses supported the motivational sequence with identified regulation (time 1), predicting intentions (time 1), and alcohol units consumed (time 2). The effects were indirect via the mediation of attitudes and PBC (time 1). A similar pattern of effects was found for the effect of time 2 psychological variables on time 3 units of alcohol consumed. There was little support for the effects of the psychological variables on binge-drinking behaviour. Findings provide new information on the psychosocial determinants of alcohol behaviour in company employees and the processes involved. Results may provide impetus for the development of interventions to reduce alcohol consumption. ©2011 The British Psychological Society.
Fukuo, Yuka; Yamashina, Shunhei; Sonoue, Hiroshi; Arakawa, Atsushi; Nakadera, Eisuke; Aoyama, Tomonori; Uchiyama, Akira; Kon, Kazuyoshi; Ikejima, Kenichi; Watanabe, Sumio
2014-09-01
Recent evidences indicate that hepatic steatosis suppresses autophagic proteolysis. The present study evaluated the correlation between autophagic function and cathepsin expression in the liver from patients with non-alcoholic fatty liver disease (NAFLD). Liver biopsy specimens were obtained from patients with chronic liver diseases (chronic hepatitis C [CHC; n = 20], chronic hepatitis B [CHB; n = 16], primary biliary cirrhosis [PBC; n = 23], NAFLD [n = 22] and control [n = 14]). The number of autophagic vesicles in hepatocytes was counted by using transmission electron microscopy. Expression of cathepsin B, D, L and p62 in the liver section was analyzed by immunohistochemical staining. The histological severity of NAFLD is assessed by NAFLD activity score (NAS). The number of autophagic vesicles in hepatocytes was significantly increased in both CHC and NAFLD groups, but not CHB and PBC, more than control. Although hepatocytes with aggregation of p62 were observed in less than 15% of CHC, p62 aggregation was detected in approximately 65% of NAFLD. Cathepsin B, D and L expression was significantly suppressed in the liver from NAFLD patients. Suppression of cathepsin B, D and L expression was not observed in CHB, CHC and PBC. In NAFLD patients, p62 aggregation was correlated with serum alanine aminotransferase value and inflammatory activity by NAS. These results indicate that a decrease in hepatic cathepsin expression in NAFLD is associated with autophagic dysfunction. Hepatic inflammation correlates with autophagic dysfunction in NAFLD. These findings indicate that the suppression of autophagic proteolysis by hepatic steatosis is involved in the pathogenesis of NAFLD. © 2013 The Japan Society of Hepatology.
Díaz-Casares, Amelia; López-González, Manuel Víctor; Peinado-Aragonés, Carlos Antonio; Lara, José Pablo; González-Barón, Salvador; Dawid-Milner, Marc Stefan
2009-07-07
To analyze the role of parabrachial complex (PBc) in the modulation of cardiorespiratory response evoked from the hypothalamic defense area (HDA), cardiorespiratory changes were analyzed in spontaneously breathing anesthetised rats in response to electrical stimulation of the HDA (1 ms pulses, 30-50 microA, 100 Hz for 5 s) before and after the microinjection of muscimol (50 nl, 0.25 nmol, 5 s) within the PBc. HDA stimulation evoked an inspiratory facilitatory response, consisting of an increase in respiratory rate (p<0.001) due to a decrease in expiratory time (p<0.01). The respiratory response was accompanied by a pressor (p<0.001) and a tachycardic (p<0.001) response. Muscimol microinjection within the lateral parabrachial region (lPB) abolished the respiratory response to HDA stimulation (p<0.01) and decreased the pressor response (p<0.05). Muscimol within the medial parabrachial region and Kölliker-Fuse (mPB-KF) decreased the magnitude of the pressor (p<0.01) and tachycardic (p<0.05) responses to HDA stimulation. The respiratory response persisted unchanged. Finally, extracellular recording of putative neurons from these regions were obtained during HDA stimulation to confirm functional interaction between HDA and parabrachial regions. 105 pontine cells were recorded during HDA stimulation, 57 from the lPB and 48 from the mPB-KF. In mPB-KF 34/48 (71%) and in lPB 38/57 (67%) cells were influenced from HDA. The results indicate that neurons from different regions of the PBc have an important function in mediating the cardiorespiratory response evoked from the HDA. The possible mechanisms involved in these interactions are discussed.
Activation of necroptosis in human and experimental cholestasis.
Afonso, Marta B; Rodrigues, Pedro M; Simão, André L; Ofengeim, Dimitry; Carvalho, Tânia; Amaral, Joana D; Gaspar, Maria M; Cortez-Pinto, Helena; Castro, Rui E; Yuan, Junying; Rodrigues, Cecília M P
2016-09-29
Cholestasis encompasses liver injury and inflammation. Necroptosis, a necrotic cell death pathway regulated by receptor-interacting protein (RIP) 3, may mediate cell death and inflammation in the liver. We aimed to investigate the role of necroptosis in mediating deleterious processes associated with cholestatic liver disease. Hallmarks of necroptosis were evaluated in liver biopsies of primary biliary cholangitis (PBC) patients and in wild-type and RIP3-deficient (RIP3 -/- ) mice subjected to common bile duct ligation (BDL). The functional link between RIP3, heme oxygenase-1 (HO-1) and antioxidant response was investigated in vivo after BDL and in vitro. We demonstrate increased RIP3 expression and mixed lineage kinase domain-like protein (MLKL) phosphorylation in liver samples of human PBC patients, coincident with thioflavin T labeling, suggesting activation of necroptosis. BDL resulted in evident hallmarks of necroptosis, concomitant with progressive bile duct hyperplasia, multifocal necrosis, fibrosis and inflammation. MLKL phosphorylation was increased and insoluble aggregates of RIP3, MLKL and RIP1 formed in BLD liver tissue samples. Furthermore, RIP3 deficiency blocked BDL-induced necroinflammation at 3 and 14 days post-BDL. Serum hepatic enzymes, fibrogenic liver gene expression and oxidative stress decreased in RIP3 -/- mice at 3 days after BDL. However, at 14 days, cholestasis aggravated and fibrosis was not halted. RIP3 deficiency further associated with increased hepatic expression of HO-1 and accumulation of iron in BDL mice. The functional link between HO-1 activity and bile acid toxicity was established in RIP3-deficient primary hepatocytes. Necroptosis is triggered in PBC patients and mediates hepatic necroinflammation in BDL-induced acute cholestasis. Targeting necroptosis may represent a therapeutic strategy for acute cholestasis, although complementary approaches may be required to control progression of chronic cholestatic liver disease.
Lammert, Craig; Juran, Brian D; Schlicht, Erik; Chan, Landon L; Atkinson, Elizabeth J; de Andrade, Mariza; Lazaridis, Konstantinos N
2014-10-01
Biochemical response to ursodeoxycholic acid among patients with primary biliary cirrhosis remains variable, and there is no agreement of an ideal model. Novel assessment of response coupled to histologic progression was recently defined by the Toronto criteria. We retrospectively assessed transplant-free survival and clinical outcomes associated with ursodeoxycholic acid response to evaluate the Toronto criteria using a large North American cohort of PBC patients. Three hundred and ninety-eight PBC patients from the Mayo Clinic PBC Genetic Epidemiology Registry were assessed for ursodeoxycholic acid treatment and biochemical response per the Toronto criteria. Responders were defined by reduction in alkaline phosphatase to less than or equal to 1.67 times the upper normal limit by 2 years of treatment, whereas non-responders had alkaline phosphatase values greater than 1.67 times the upper normal limit. Probability of survival was estimated using the Kaplan-Meier method. Three hundred and two (76 %) patients were responders and 96 (24 %) were non-responders. Significantly more non-responders developed adverse events related to chronic liver disease compared to responders (hazard ratio (HR) 2.77, P = 0.001). Biochemical responders and early-stage disease at treatment start was associated with improved overall transplant-free survival compared to non-responders (HR 1.9) and patients with late-stage disease (HR 2.7) after age and sex adjustment. The Toronto criteria are capable of identifying ursodeoxycholic acid-treated primary biliary cirrhosis patients at risk of poor transplant-free survival and adverse clinical outcomes. Our data reveal that despite advanced disease at diagnosis, biochemical response per the Toronto criteria associates with improved overall transplant-free survival.
Cooke, Richard; French, David P
2008-01-01
Meta-analysis was used to quantify how well the Theories of Reasoned Action and Planned Behaviour have predicted intentions to attend screening programmes and actual attendance behaviour. Systematic literature searches identified 33 studies that were included in the review. Across the studies as a whole, attitudes had a large-sized relationship with intention, while subjective norms and perceived behavioural control (PBC) possessed medium-sized relationships with intention. Intention had a medium-sized relationship with attendance, whereas the PBC-attendance relationship was small sized. Due to heterogeneity in results between studies, moderator analyses were conducted. The moderator variables were (a) type of screening test, (b) location of recruitment, (c) screening cost and (d) invitation to screen. All moderators affected theory of planned behaviour relationships. Suggestions for future research emerging from these results include targeting attitudes to promote intention to screen, a greater use of implementation intentions in screening information and examining the credibility of different screening providers.
Gui, Tao; Zhang, Meiling; Chen, Jianwen; Zhang, Yuanliang; Zhou, Naru; Zhang, Yu; Tao, Jia; Sui, Liucai; Li, Yunsheng; Liu, Ya; Zhang, Xiaorong; Zhang, Yunhai
2012-08-01
A vector expressing human lysozyme (pBC1-hLYZ-GFP-Neo) was evaluated for gene and protein expression following liposome-mediated transformation of C-127 mouse mammary cancer cells. Cultures of G418-resistant clones were harvested 24-72 h after induction with prolactin, insulin and hydrocortisone. Target gene expression was analyzed by RT-PCR and Western blot and recombinant human lysozyme (rhLYZ) bacteriostatic activity was also evaluated. The hLYZ gene was correctly transcribed and translated in C-127 cells and hLYZ inhibited gram-positive bacterial growth, indicating the potential of this expression vector for development of a mammary gland bioreactor in goats. Guanzhong dairy goat skin fibroblasts transfected with pBC1-hLYZ-GFP-Neo were used to construct a goat embryo transgenically expressing rhLYZ by somatic nuclear transplantation with a blastocyst rate of 9.0 ± 2.8 %. These data establish the basis for cultivation of mastitis-resistant hLYZ transgenic goats.
Qadir, Rabah; Sidhu, Sanbir; Ochsner, J Lockwood; Meyer, Mark S; Chimento, George F
2014-08-01
Efficacy of antibiotic cement (ALBC) in primary knee arthroplasty (pTKA) has been debated. The study's purpose was to examine efficacy of ALBC versus plain cement (PBC) in preventing infection in high-risk patients undergoing pTKA. 3292 consecutive pTKAs were divided into three cohorts: (1) patients receiving only PBC, (2) patients receiving only ALBC, and (3) only high-risk patients receiving ALBC. Cohorts' infections were compared. The 30-day infection rates for cohorts 1, 2, 3 were 0.29%, 0.20%, and 0.13% respectively. 6-month rates were 0.39%, 0.54% and 0.38%. 1-year rates were 0.78%, 0.61%, and 0.64%. Differences in infection rates at all time intervals were not statistically significant. The study supports that even judicious risk-stratified usage of ALBC may not confer added benefit in decreasing infection at one year. Copyright © 2014 Elsevier Inc. All rights reserved.
Skin dose for head and neck cancer patients treated with intensity-modulated radiation therapy(IMRT)
NASA Astrophysics Data System (ADS)
Fu, Hsiao-Ju; Li, Chi-Wei; Tsai, Wei-Ta; Chang, Chih-Chia; Tsang, Yuk-Wah
2017-11-01
The reliability of thermoluminescent dosimeters (ultrathin TLD) and ISP Gafchromic EBT2 film to measure the surface dose in phantom and the skin dose in head-and-neck patients treated with intensity-modulated radiation therapy technique(IMRT) is the research focus. Seven-field treatment plans with prescribed dose of 180 cGy were performed on Eclipse treatment planning system which utilized pencil beam calculation algorithm(PBC). In calibration tests, the variance coefficient of the ultrathin TLDs were within 3%. The points on the calibration curve of the Gafchromic film was within 1% variation. Five measurements were taken on phantom using ultrathin TLD and EBT2 film respectively. The measured mean surface doses between ultrathin TLD or EBT2 film were within 5% deviation. Skin doses of 6 patients were measured for initial 5 fractions and the mean dose per-fraction was calculated. If the extrapolated doses for 30 fractions were below 4000 cGy, the skin reaction grading observed according to Radiation Therapy Oncology Group (RTOG) was either grade 1 or grade 2. If surface dose exceeded 5000 cGy in 32 fractions, then grade 3 skin reactions were observed.
Growth morphology of epsomite (MgSO 4·7H 2O)
NASA Astrophysics Data System (ADS)
Rubbo, Marco; Aquilano, Dino; Franchini-Angela, Marinella; Sgualdino, Giulio
1985-06-01
A first approach to the study of the growth properties of epsomite (MgSO 4·7H 2O) is presented. Particular attention is payed to the growth forms and to epitaxy relations between epsomite and some known habit modifiers. The starting point of the study is the Hartman and Perdok PBC analysis. It proves to be essential for knowing the actual surface profiles. Successively the theoretical growth morphology is given taking into account: the broken-bond model of Wolff and Broder, the energies associated to the hydrogen bonds only, and finally the attachment energies calculated on the basis of the Coulomb potential. Furthermore an analysis of 2D coincidence lattices leads us to the conclusion that a 2D epitaxy of both Na 2B 4O 7·lOH 2O and/or Na 2SO 4·lOH 2O on {111} and/or ? forms of epsomite explains the effect of borax and Glauber's salt as habit modifiers.
Structural morphology of YBa 2Cu 3O 7- x
NASA Astrophysics Data System (ADS)
Sun, B. N.; Hartman, P.; Woensdregt, C. F.; Schmid, H.
1990-03-01
The structural morphology of YBa 2Cu 3O 7- x (YBCO) has been investigated by application of the periodic bond chain (PBC) theory. For x=1, the F forms were found to be {001}, {011}, {013}, {112} and {114}. Attachment energies have been calculated in broken bond model and in an electrostatic point charge model. For x=1 the theoretical growth habit is tabular to platy {001} with {011} as side faces. For x=0 {010} also becomes an F form. The habit is isometric with large {001} and {011} and small {010} faces. The outermost layer of {001} contains half of the Cu + ( x=1) or Cu 3+ and O 2- ( x=0) ions in an ordered arrangement based on a c(2x2) quadratic lattice. For the outermost layer of (010) ( x=0) an ordering scheme of the copper and oxygen ions is proposed. The occurrence of {010} rather than {011} on grown crystals has to be ascribed to external factors.
Theory of Planned Behavior and Teachers' Decisions regarding Use of Educational Technology
ERIC Educational Resources Information Center
Lee, Jung; Cerreto, Frank A.; Lee, Jihyun
2010-01-01
According to Ajzen's Theory of Planned Behavior (TPB), behavioral intention (BI) is predicted by attitude toward the behavior (AB), subjective norm (SN), and perceived behavioral control (PBC). Previous studies using the TPB to explain teachers' intentions to use technology have resulted in inconsistent findings. This inconsistency might be due to…
ERIC Educational Resources Information Center
La Londe, Priya G.
2017-01-01
The Chinese province of Shanghai has gained international recognition as a high performing education system with strong teaching and learning outcomes. One accountability mechanism in Shanghai's education reform strategy is statewide performance-based compensation (PBC), also known as performance- or merit pay. Providing a first time account of…
ERIC Educational Resources Information Center
Vermeulen, Marjan; Kreijns, Karel; van Buuren, Hans; Van Acker, Frederik
2017-01-01
This study investigated whether school organizational variables (ie, transformative leadership (TL), ICT-infrastructure (technical and social) and organizational learning climate were related to teachers' dispositional variables (ie, attitude, perceived norm and perceived behavior control [PBC]). The direct and indirect influences of the…
The unfinished business of primary biliary cirrhosis.
Selmi, Carlo; Zuin, Massimo; Gershwin, M Eric
2008-09-01
In nearly every multifactorial human disease, there are three periods that characterize our understanding and definition. First, there is a period in which there is rapid accumulation of descriptive data. Second, there is a longer and slower period as information is obtained that redefines and expands basic and clinical knowledge that lacks the final and important area of understanding aetiology and therapeutic intervention. Third, which is much less common for most diseases, is the vigorous definition of pathobiology and treatment. These phases are well illustrated by our current understanding of primary biliary cirrhosis (PBC). The term PBC was first used nearly 60 years ago and for the first 40 or so years, the primary research efforts were directed at clinical definitions and pathology. Subsequently, with the advent of molecular biology, there began a rigorous dissection of the immune response and, in particular, a better understanding of anti-mitochondrial antibodies. These efforts have greatly helped in our understanding of not only the effector mechanisms of disease, but also the uniqueness of the primary target tissue, biliary epithelium. However, this research has still not led to successful translation for specific therapy.
NASA Astrophysics Data System (ADS)
Gruber, G.; Cottom, J.; Meszaros, R.; Koch, M.; Pobegen, G.; Aichinger, T.; Peters, D.; Hadley, P.
2018-04-01
SiC based metal-oxide-semiconductor field-effect transistors (MOSFETs) have gained a significant importance in power electronics applications. However, electrically active defects at the SiC/SiO2 interface degrade the ideal behavior of the devices. The relevant microscopic defects can be identified by electron paramagnetic resonance (EPR) or electrically detected magnetic resonance (EDMR). This helps to decide which changes to the fabrication process will likely lead to further increases of device performance and reliability. EDMR measurements have shown very similar dominant hyperfine (HF) spectra in differently processed MOSFETs although some discrepancies were observed in the measured g-factors. Here, the HF spectra measured of different SiC MOSFETs are compared, and it is argued that the same dominant defect is present in all devices. A comparison of the data with simulated spectra of the C dangling bond (PbC) center and the silicon vacancy (VSi) demonstrates that the PbC center is a more suitable candidate to explain the observed HF spectra.
Mechanism by which BMI influences leisure-time physical activity behavior.
Godin, Gaston; Bélanger-Gravel, Ariane; Nolin, Bertrand
2008-06-01
The objective of this prospective study was to clarify the mechanism by which BMI influences leisure-time physical activity. This was achieved in accordance with the assumptions underlying the Theory of Planned Behavior (TPB), considered as one of the most useful theories to predict behavior adoption. At baseline, a sample of 1,530 respondents completed a short questionnaire to measure intention and perceived behavioral control (PBC), the two proximal determinants of behavior of TPB. Past behavior, sociodemographic variables, and weight and height were also assessed. The dependent variable, leisure-time physical activity was assessed 3 months later. Hierarchical multiple regression analyses revealed that BMI is a direct predictor of future leisure-time physical activity, not mediated by the variables of TPB. Additional hierarchical analyses indicated that BMI was not a moderator of the intention-behavior and PBC-behavior relationships. The results of this study suggest that high BMI is a significant negative determinant of leisure-time physical activity. This observation reinforces the importance of preventing weight gain as a health promotion strategy for avoiding a sedentary lifestyle.
Leung, Kit Sang; Ben Abdallah, Arbi; Cottler, Linda B.
2009-01-01
Risk perception, perceived behavioral control of obtaining ecstasy (PBC-obtaining), current ecstasy dependence, and recent depression have been associated with past ecstasy use, however, their utility in predicting ecstasy use has not been demonstrated. This study aimed to determine whether these four modifiable risk factors could predict ecstasy use after controlling for socio-demographic covariates and recent polydrug use. Data from 601 ecstasy users in the National Institute on Drug Abuse funded TriCity Study of Club Drug Use, Abuse and Dependence were analyzed using multivariate logistic regression. Participants were interviewed twice within a 2-week period using standardized instruments. Thirteen percent (n=80) of the participants reported using ecstasy between the two interviews. Low risk perception, high PBC-obtaining (an estimated ecstasy procurement time < 24 hours), and current ecstasy dependence were statistically associated with ecstasy use between the two interviews. Recent depression was not a significant predictor. Despite not being a target predictor, recent polydrug use was also statistically associated with ecstasy use. The present findings may inform the development of interventions targeting ecstasy users. PMID:19880258
Tomasone, Jennifer R; Sweet, Shane N; McReynolds, Stuart; Martin Ginis, Kathleen A
2017-09-01
Changing Minds, Changing Lives, a seminar-mediated behavior change intervention, aims to enhance health care professionals' (HCPs') social cognitions for discussing leisure-time physical activity (LTPA) with patients with physical disabilities. This study examines which seminar implementation variables (presenter characteristics, delivery components) predict effectiveness using multilevel modeling. HCP trainees (n = 564) attended 24 seminars and completed Theory of Planned Behavior-based measures for discussing LTPA at pre-, post-, 1-month post-, and 6-months post-seminar. Implementation variables were extracted from presenter-completed questionnaires/checklists. Seminars presented by a HCP predicted positive changes in all cognitions pre-post but negative changes in attitudes and perceived behavioral control (PBC) over follow-up (ps < .05). The number of seminars the presenter had delivered predicted negative changes in attitudes and PBC during follow-up (ps < .001). Inclusion of audiovisual components predicted positive changes in attitudes pre-post (p < .001). Presenter characteristics may be "key ingredients" to educational interventions for HCPs; however, future studies should examine additional implementation variables.
Presseau, Justin; Sniehotta, Falko F; Francis, Jill J; Gebhardt, Winifred A
2010-11-01
Integration of a multiple goal theory approach into the theory of planned behaviour (TPB) to investigate how the perceived facilitating and conflicting relationships in multiple goal pursuit predict performance of a health-related behaviour. Prospective design with 8-week follow-up. At baseline, perceived intergoal facilitation and intergoal conflict were measured using personal projects analysis supplemented with standard TPB measures for physical activity (PA). Self-reported PA was measured at follow-up 8 weeks later. N=137 participants completed measures at both time points (55.4% response rate at follow-up). Hierarchical regression showed that perceived intergoal facilitation, but not intergoal conflict, directly predicted PA beyond intention and perceived behavioural control (PBC), accounting for more than 4% of additional variance in PA. Intergoal facilitation had an indirect effect on intention through attitude and PBC, and intention partially mediated the effect of intergoal facilitation on behaviour. The perceived facilitating effect of pursuing other personal goals predicts the performance of a health-related behaviour over and above single behaviour-focused social cognitions.
Combined horizontal and vertical integration of care: a goal of practice-based commissioning.
Thomas, Paul; Meads, Geoffrey; Moustafa, Ahmet; Nazareth, Irwin; Stange, Kurt C; Donnelly Hess, Gertrude
2008-01-01
Practice-based commissioning (PBC) in the UK is intended to improve both the vertical and horizontal integration of health care, in order to avoid escalating costs and enhance population health. Vertical integration involves patient pathways to treat named medical conditions that transcend organisational boundaries and connect community-based generalists with largely hospital-sited specialists, whereas horizontal integration involves peer-based and cross-sectoral collaboration to improve overall health. Effective mechanisms are now needed to permit ongoing dialogue between the vertical and horizontal dimensions to ensure that medical and nonmedical care are both used to their best advantage. This paper proposes three different models for combining vertical and horizontal integration - each is a hybrid of internationally recognised ideal types of primary care organisation. Leaders of PBC should consider a range of models and apply them in ways that are relevant to the local context. General practitioners, policy makers and others whose job it is to facilitate horizontal and vertical integration must learn to lead such combined approaches to integration if the UK is to avoid the mistakes of the USA in over-medicalising health issues.
Determination of serum albumin, analytical challenges: a French multicenter study.
Rossary, Adrien; Blondé-Cynober, Françoise; Bastard, Jean-Philippe; Beauvieux, Marie-Christine; Beyne, Pascale; Drai, Jocelyne; Lombard, Christine; Anglard, Ingrid; Aussel, Christian; Claeyssens, Sophie; Vasson, Marie-Paule
2017-06-01
Among the biological markers of morbidity and mortality, albumin holds a key place in the range of criteria used by the High Authority for Health (HAS) for the assessment of malnutrition and the coding of information system medicalization program (PMSI). If the principle of quantification methods have not changed in recent years, the dispersion of external evaluations of the quality (EEQ) data shows that the standardization using the certified reference material (CRM) 470 is not optimal. The aim of this multicenter study involving 7 sites, conducted by a working group of the French Society of Clinical Biology (SFBC), was to assess whether the albuminemia values depend on the analytical system used. The albumin from plasma (n=30) and serum (n=8) pools was quantified by 5 different methods [bromocresol green (VBC) and bromocresol purple (PBC) colorimetry, immunoturbidimetry (IT), immunonephelometry (IN) and capillary electrophoresis (CE)] using 12 analyzers. Bland and Altman's test evaluated the difference between the results obtained by the different methods. For example, a difference as high as 13 g/L was observed for the same sample between the methods (p <0.001) in the concentration range of 30 to 35 g/L. The VBC overestimates albumin across the range of values tested compared to PBC (p <0.05). PBC method gives similar results to IN for values lower than 40 g/L. For IT methods, one of the technical/analyzer tandem underestimates the albumin values inducing a difference of performance between the immunoprecipitation methods (IT vs IN, p <0.05). Although, the albumin results are related to the technical/analyzer tandem used. This variability is usually not taken into account by the clinician. Thus, clinicians and biologists have to be aware and have to check, depending on the method used, the albumin thresholds identified as risk factors for complications related to malnutrition and PMSI coding.
Gondré-Lewis, Marjorie C; Warnock, Kaitlin T; Wang, Hong; June, Harry L; Bell, Kimberly A; Rabe, Holger; Tiruveedhula, Veera Venkata Naga Phani Babu; Cook, James; Lüddens, Hartmut; Aurelian, Laure; June, Harry L
2016-01-01
Childhood stress and trauma are associated with substance use disorders in adulthood, but the neurological changes that confer increased vulnerability are largely unknown. In this study, maternal separation (MS) stress, restricted to the pre-weaning period, was used as a model to study mechanisms of protracted effects of childhood stress/traumatic experiences on binge drinking and impulsivity. Using an operant self-administration model of binge drinking and a delay discounting assay to measure impulsive-like behavior, we report that early life stress due to MS facilitated acquisition of binge drinking and impulsivity during adulthood in rats. Previous studies have shown heightened levels of corticotropin releasing factor (CRF) after MS, and here, we add that MS increased expression levels of GABA(A) α2 subunit in central stress circuits. To investigate the precise role of these circuits in regulating impulsivity and binge drinking, the CRF1 receptor antagonist antalarmin and the novel GABA(A) α2 subunit ligand 3-PBC were infused into the central amygdala (CeA) and medial prefrontal cortex (mPFC). Antalarmin and 3-PBC at each site markedly reduced impulsivity and produced profound reductions on binge-motivated alcohol drinking, without altering responding for sucrose. Furthermore, whole-cell patch-clamp studies showed that low concentrations of 3-PBC directly reversed the effect of relatively high concentrations of ethanol on α2β3γ2 GABA(A) receptors, by a benzodiazepine site-independent mechanism. Together, our data provide strong evidence that maternal separation, i.e. early life stress, is a risk factor for binge drinking, and is linked to impulsivity, another key risk factor for excessive alcohol drinking. We further show that pharmacological manipulation of CRF and GABA receptor signaling is effective to reverse binge drinking and impulsive-like behavior in MS rats. These results provide novel insights into the role of the brain stress systems in the development of impulsivity and excessive alcohol consumption.
Fischer, Bradford D.; Teixeira, Laura P.; van Linn, Michael L.; Namjoshi, Ojas A.; Cook, James M.; Rowlett, James K.
2013-01-01
Rationale Assays of schedule-controlled responding can be used to characterize the pharmacology of benzodiazepines and other GABAA receptor modulators, and are sensitive to changes in drug effects that are related to physical dependence. Objective The present study used this approach to investigate the role of GABAA receptor subtypes in mediating dependence-like effects following benzodiazepine administration. Methods Squirrel monkeys (n=6) were trained on a fixed-ratio schedule of food reinforcement. Initially, the response rate-decreasing effects of chlordiazepoxide (0.1–10 mg/kg; nonselective GABAA receptor agonist), zolpidem (0.032–1.0 mg/kg; α1 subunit-containing GABAA subtype-preferring agonist) and HZ-166 (0.1–10 mg/kg; functionally selective α2 and α3 subunit-containing GABAA receptor agonist) were assessed. Next, acute dependence-like effects following single injections of chlordiazepoxide, zolpidem and HZ-166 were assessed with flumazenil (0.1–3.2 mg/kg; nonselective GABAA receptor antagonist). Finally, acute dependence-like effects following zolpidem administration were assessed with βCCt and 3-PBC (0.1–3.2 mg/kg and 0.32–10 mg/kg, respectively; α1 subunit-containing GABAA receptor antagonists). Results Chlordiazepoxide, zolpidem and HZ-166 produced dose- and time-dependent decreases in response rates, whereas flumazenil, βCCt and 3-PBC were ineffective. After the drug effects waned, flumazenil produced dose-dependent decreases in response rates following administration of 10 mg/kg chlordiazepoxide and 1.0 mg/kg zolpidem, but not following any dose of HZ-166. Further, both βCCt and 3-PBC produced dose-dependent decreases in response rates when administered after 1.0 mg/kg zolpidem. Conclusions These data raise the possibility that α1 subunit-containing GABAA receptors play a major role in physical dependence-related behaviors following a single injection of a benzodiazepine. PMID:23354533
Fischer, Bradford D; Teixeira, Laura P; van Linn, Michael L; Namjoshi, Ojas A; Cook, James M; Rowlett, James K
2013-05-01
Assays of schedule-controlled responding can be used to characterize the pharmacology of benzodiazepines and other GABAA receptor modulators, and are sensitive to changes in drug effects that are related to physical dependence. The present study used this approach to investigate the role of GABAA receptor subtypes in mediating dependence-like effects following benzodiazepine administration. Squirrel monkeys (n = 6) were trained on a fixed-ratio schedule of food reinforcement. Initially, the response rate-decreasing effects of chlordiazepoxide (0.1-10 mg/kg; nonselective GABAA receptor agonist), zolpidem (0.032-1.0 mg/kg; α1 subunit-containing GABAA subtype-preferring agonist), and HZ-166 (0.1-10 mg/kg; functionally selective α2 and α3 subunit-containing GABAA receptor agonist) were assessed. Next, acute dependence-like effects following single injections of chlordiazepoxide, zolpidem, and HZ-166 were assessed with flumazenil (0.1-3.2 mg/kg; nonselective GABAA receptor antagonist). Finally, acute dependence-like effects following zolpidem administration were assessed with βCCt and 3-PBC (0.1-3.2 mg/kg and 0.32-10 mg/kg, respectively; α1 subunit-containing GABAA receptor antagonists). Chlordiazepoxide, zolpidem, and HZ-166 produced dose- and time-dependent decreases in response rates, whereas flumazenil, βCCT, and 3-PBC were ineffective. After the drug effects waned, flumazenil produced dose-dependent decreases in response rates following administration of 10 mg/kg chlordiazepoxide and 1.0 mg/kg zolpidem, but not following any dose of HZ-166. Further, both βCCT and 3-PBC produced dose-dependent decreases in response rates when administered after 1.0 mg/kg zolpidem. These data raise the possibility that α1 subunit-containing GABAA receptors play a major role in physical dependence-related behaviors following a single injection of a benzodiazepine.
Agarwal, Anurag; Dhama, Vipin; Manik, Yogesh K; Upadhyaya, M K; Singh, C S; Rastogi, V
2015-02-01
Trigeminal neuralgia (TN) is characterized by unilateral, lancinating, paroxysmal pain in the dermatomal distribution area of trigeminal nerve. Percutaneous balloon compression (PBC) of Gasserian ganglion is an effective, comparatively cheaper and simple therapeutic modality for treatment of TN. Compression secondary to PBC selectively injures the large myelinated A-alfa (afferent) fibers that mediate light touch and does not affect A-delta and C-fibres, which carry pain sensation. Balloon compression reduces the sensory neuronal input, thus turning off the trigger to the neuropathic trigeminal pain. In this current case series, we are sharing our experience with PBC of Gasserian Ganglion for the treatment of idiopathic TN in our patients at an academic university-based medical institution in India. During the period of August 2012 to October 2013, a total of twelve PBCs of Gasserian Ganglion were performed in eleven patients suffering from idiopathic TN. There were nine female patients and two male patients with the age range of 35-70 years (median age: 54 years). In all patients cannulation of foramen ovale was done successfully in the first attempt. In eight out of eleven (72.7%) patients ideal 'Pear-shaped' balloon visualization could be achieved. In the remaining three patients (27.3%), inflated balloon was 'Bullet-shaped'. In one patient final placement of Fogarty balloon was not satisfactory and it ruptured during inflation. This case was deferred for one week when it was completed successfully with 'Pear-shaped' balloon inflation. During the follow up period of 1-13 months, there have been no recurrences of TN. Eight out of eleven patients (72.7%) are completely off medicines (carbamazepine and baclofen) and other two patients are stable on very low doses of carbamazepine. All patients have reported marked improvement in quality of life. This case series shows that percutaneous balloon compression is a useful minimally invasive intervention for the treatment of trigeminal neuralgia.
Kawakami, Shigehisa; Kumazaki, Yohei; Manda, Yosuke; Oki, Kazuhiro; Minagi, Shogo
2014-01-01
Aim The role of parafunctional masticatory muscle activity in tooth loss has not been fully clarified. This study aimed to reveal the characteristic activity of masseter muscles in bite collapse patients while awake and asleep. Materials and Methods Six progressive bite collapse patients (PBC group), six age- and gender-matched control subjects (MC group), and six young control subjects (YC group) were enrolled. Electromyograms (EMG) of the masseter muscles were continuously recorded with an ambulatory EMG recorder while patients were awake and asleep. Diurnal and nocturnal parafunctional EMG activity was classified as phasic, tonic, or mixed using an EMG threshold of 20% maximal voluntary clenching. Results Highly extended diurnal phasic activity was observed only in the PBC group. The three groups had significantly different mean diurnal phasic episodes per hour, with 13.29±7.18 per hour in the PBC group, 0.95±0.97 per hour in the MC group, and 0.87±0.98 per hour in the YC group (p<0.01). ROC curve analysis suggested that the number of diurnal phasic episodes might be used to predict bite collapsing tooth loss. Conclusion Extensive bite loss might be related to diurnal masticatory muscle parafunction but not to parafunction during sleep. Clinical Relevance: Scientific rationale for study Although mandibular parafunction has been implicated in stomatognathic system breakdown, a causal relationship has not been established because scientific modalities to evaluate parafunctional activity have been lacking. Principal findings This study used a newly developed EMG recording system that evaluates masseter muscle activity throughout the day. Our results challenge the stereotypical idea of nocturnal bruxism as a strong destructive force. We found that diurnal phasic masticatory muscle activity was most characteristic in patients with progressive bite collapse. Practical implications The incidence of diurnal phasic contractions could be used for the prognostic evaluation of stomatognathic system stability. PMID:25010348
West, N H; Burggren, W W
1982-02-01
Gill ventilation frequency (fG), the pressure amplitude (PBC) and stroke volume (VS) of buccal ventilation cycles, the frequency of air breaths (fL), water flow over the gills (VW), gill oxygen uptake (MGO2), oxygen utilization (U), and heart frequency (fH) have been measured in unanaesthetized, air breathing Rana catesbeiana tadpoles (stage XVI-XIX). The animals were unrestrained except for ECG leads or cannulae, and were able to surface voluntarily for air breathing. They were subjected to aquatic normoxia, hyperoxia and three levels of aquatic hypoxia, and their respiratory responses recorded in the steady state. The experiments were performed at 20 +/- 0.5 degrees C. In hyperoxia there was an absence of air breathing, and fG, PBC and VW fell from the normoxic values, while U increased, resulting in no significant change in MGO2. Animals in normoxia showed a very low fL which increased in progressively more hypoxic states. VW increased from the normoxic value in mild hypoxia (PO2 = 96 +/- 2 mm Hg), but fell, associated with a reduction in PBC, in moderate (PO2 = 41 +/- 1 mm Hg) and severe (PO2 = 21 +/- 3 mm Hg) hypoxia in the presence of lung ventilation. Gill MGO2 was not significantly different from the normoxic value in mild hypoxia but fell in moderate hypoxia, while in severe hypoxia oxygen was lost to the ventilating water from the blood perfusing the gills. There was no significant change in fH from the normoxic value in either hypoxia or hyperoxia. These data indicate, that in the bimodally breathing bullfrog tadpole, aquatic PO2 exerts a strong control over both gill and lung ventilation. Furthermore, there is an interaction between gill and lung ventilation such that the onset of a high frequency of lung ventilation in moderate and severe hypoxia promotes a suppression of gill ventilation cycles.
Identifying Sources of Volatile Organic Compounds and Aldehydes in a High Performance Building
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ortiz, Anna C.; Russell, Marion; Lee, Wen-Yee
The developers of the Paharpur Business Center (PBC) and Software Technology Incubator Park in New Delhi, India offer an environmentally sustainable building with a strong emphasis on energy conservation, waste minimization and superior indoor air quality (IAQ). To achieve the IAQ goal, the building utilizes a series of air cleaning technologies for treating the air entering the building. These technologies include an initial water wash followed by ultraviolet light treatment and biolfiltration using a greenhouse located on the roof and numerous plants distributed throughout the building. Even with the extensive treatment of makeup air and room air in the PBC,more » a recent study found that the concentrations of common volatile organic compounds and aldehydes appear to rise incrementally as the air passes through the building from the supply to the exhaust. This finding highlights the need to consider the minimization of chemical sources in buildings in combination with the use of advanced air cleaning technologies when seeking to achieve superior IAQ. The goal of this project was to identify potential source materials for indoor chemicals in the PBC. Samples of building materials, including wood paneling (polished and unpolished), drywall, and plastic from a hydroponic drum that was part of the air cleaning system, were collected from the building for testing. All materials were collected from the PBC building and shipped to the Lawrence Berkeley National Laboratory (LBNL) for testing. The materials were pre-conditioned for two different time periods before measuring material and chemical specific emission factors for a range of VOCs and Aldehydes. Of the six materials tested, we found that the highest emitter of formaldehyde was new plywood paneling. Although polish and paint contribute to some VOC emissions, the main influence of the polish was in altering the capacity of the surface to accumulate formaldehyde. Neither the new nor aged polish contributed significantly to formaldehyde emissions. The VOC emission stream (excluding formaldehyde) was composed of up to 18 different chemicals and the total VOC emissions ranged in magnitude from 7 mu g/m2/h (old wood with old polish) to>500 mu g/m2/h (painted drywall). The formaldehyde emissions from drywall and old wood with either new or old polish were ~;;15 mu g/m2/h while the new wood material emitted>100 mu g/m2/h. However, when the projected surface area of each material in the building was considered, the new wood, old wood and painted drywall material all contributed substantially to the indoor formaldehyde loading while the coatings contributed primarily to the VOCs.« less
Systematic bias of correlation coefficient may explain negative accuracy of genomic prediction.
Zhou, Yao; Vales, M Isabel; Wang, Aoxue; Zhang, Zhiwu
2017-09-01
Accuracy of genomic prediction is commonly calculated as the Pearson correlation coefficient between the predicted and observed phenotypes in the inference population by using cross-validation analysis. More frequently than expected, significant negative accuracies of genomic prediction have been reported in genomic selection studies. These negative values are surprising, given that the minimum value for prediction accuracy should hover around zero when randomly permuted data sets are analyzed. We reviewed the two common approaches for calculating the Pearson correlation and hypothesized that these negative accuracy values reflect potential bias owing to artifacts caused by the mathematical formulas used to calculate prediction accuracy. The first approach, Instant accuracy, calculates correlations for each fold and reports prediction accuracy as the mean of correlations across fold. The other approach, Hold accuracy, predicts all phenotypes in all fold and calculates correlation between the observed and predicted phenotypes at the end of the cross-validation process. Using simulated and real data, we demonstrated that our hypothesis is true. Both approaches are biased downward under certain conditions. The biases become larger when more fold are employed and when the expected accuracy is low. The bias of Instant accuracy can be corrected using a modified formula. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
NASA Astrophysics Data System (ADS)
Tankersley, R. A.; Bourexis, P.; Kaser, J. S.
2011-12-01
Within the research and academic communities there is a growing interest in improving the communication skills of scientists, especially their ability to communicate the substance and importance of their research to general audiences. To address this need, we developed an intensive, two-day workshop [Presentation Boot Camp (PBC)] that focuses on presenting scientific concepts and research findings more effectively to both scientific/technical audiences and the general public. Through a series of interactive sessions, participants receive training in planning and preparing presentations that communicate messages more clearly and effectively and that have a lasting impact on the audience. Topics include: knowing and identifying the needs of the audience, highlighting big ideas and take-home messages, designing effective visuals, decoding complex concepts with diagrams, and displaying data in meaningful ways. PBC attendees also receive training in the use and application of the Presentation Skills Protocol (PSP) and associated rubric for evaluating the effectiveness of scientific presentations. The PSP was originally developed as part of a NSF Graduate Teaching Fellows in K-12 Education Program (GK-12) to assess and track the impact of the GK-12 experience on the communication skills of Graduate Teaching Fellows. The PSP focuses on eleven presentation skill sets, including organization, accuracy, relevance, message, language, equity, delivery, technology, use of time, questions, and presence. The associated rubric operationally defines each of the skill sets at three categorical levels of competence: (1) proficient, (2) developing, and (3) needs attention. The PSP may be used to (1) provide scientists with regular and consistent feedback on the quality and effectiveness of their classroom and research presentations and (2) design professional development activities and training programs that target specific presentation skills. However, our evaluation results indicate that use of the PSP alone does not guarantee communication growth or competence. To achieve significant gains in presentation skills, a three pronged approach is required: (1) formal training in best-practices and techniques for preparing and delivering presentations (e.g., Presentation Boot Camp), (2) frequent opportunities to practice and hone presentation skills (e.g., presentations at professional meetings, informal science centers, and K-12 classrooms), and (3) regular, individualized and structured feedback (e.g., Presentations Skill Protocol).
Ng, W.-F.; Stangroom, A.J.; Davidson, A.; Wilton, K.; Mitchell, S.; Newton, J.L.
2012-01-01
Background: Symptoms in keeping with autonomic dysfunction are commonly described by primary Sjögrens syndrome patients (pSS); whether objective abnormalities of autonomic function occur is unclear. This study set out to explore dynamic cardiovascular autonomic responses in pSS and their relationship with symptoms and quality of life. Methods: Twenty-one people from the UK pSS registry, 21 community controls and 21 patients with the autoimmune liver disease primary biliary cirrhosis (PBC) (matched case-wise for age and sex) attended for assessment of autonomic responses to orthostasis and Valsalva manoeuvre (VM). pSS patients also completed EULAR Sjögrens Syndrome patient-reported index (ESSPRI), EULAR Sjögren’s syndrome disease activity index (ESSDAI), fatigue impact scale and EURO-QOL 5-dimension (EQ-5D). Results: Compared with controls, pSS patients had significantly lower baseline systolic blood pressure (SBP) (114 ± 13 vs. 127 ± 20; P = 0.02), which dropped to a significantly lower value (98 ± 22 vs. 119 ± 24, P = 0.009). When area under the curve (AUC) was calculated for when the SBP was below baseline this was significantly greater in pSS compared to both control groups (pSS vs. control vs. PBC: 153 ± 236 vs. 92 ± 85 vs. 1.2 ± 0.3, P = 0.005). Peak phase IV SBP during the VM was significantly lower in pSS (P = 0.007) indicating early sympathetic failure. Increased heart rate associated with fatigue (P = 0.02; r2 = 0.2) and EQ-5D. A shift in sympathetic-vagal balance associated with overall symptom burden (ESSPRI) (P = 0.04, r2 = 0.3) and EULAR sicca score (P = 0.016; r2 = 0.3), the latter also correlated with baroreceptor effectiveness (P = 0.03; r2 = 0.2) and diastolic blood pressure variability (P = 0.003; r2 = 0.4). Conclusion: pSS patients have impaired blood pressure response to standing. Dysautonomia correlates with PSS-associated symptoms and quality of life. PMID:22976617
Arapiraca, A F C; Jonsson, Dan; Mohallem, J R
2011-12-28
We report an upgrade of the Dalton code to include post Born-Oppenheimer nuclear mass corrections in the calculations of (ro-)vibrational averages of molecular properties. These corrections are necessary to achieve an accuracy of 10(-4) debye in the calculations of isotopic dipole moments. Calculations on the self-consistent field level present this accuracy, while numerical instabilities compromise correlated calculations. Applications to HD, ethane, and ethylene isotopologues are implemented, all of them approaching the experimental values.
USDA-ARS?s Scientific Manuscript database
A new group of phenolic branched-chain fatty acids (n-PBC-FA), hybrid molecules of natural monophenols (i.e., thymol, carvacrol and creosote) and mixed fatty acid (i.e., derived from soybean and safflower oils), were efficiently produced through a process known as arylation. The reaction involves a...
Variable broad lines and outflow in the weak blazar PBC J2333.9-2343
NASA Astrophysics Data System (ADS)
Hernández-García, L.; Vietri, G.; Panessa, F.; Piconcelli, E.; Chavushyan, V.; Jiménez-Andrade, E. F.; Bassani, L.; Bazzano, A.; Cazzoli, S.; Malizia, A.; Masetti, N.; Monaco, L.; Pović, M.; Saviane, I.; Ubertini, P.
2018-05-01
PBC J2333.9-2343 is a peculiar active nucleus with two giant radio lobes and a weak blazar-like nucleus at their center. In the present work we show new optical, UV, and X-ray data taken from the San Pedro Mártir telescope, the New Technology Telescope, NTT/EFOSC2, and the Swift/XRT satellite. The source is highly variable at all frequencies, in particular the strongest variations are found in the broad Hα component with a flux increase of 61±4 per cent between 2009 and 2016, following the X-ray flux increase of 62±6 per cent between 2010 and 2016. We also detected a broad Hβ component in 2016, making the optical classification change from type 1.9 to type 1.8 in one year. We have also detected a broad component of the [OIII]λ5007 line, which is blue-shifted and of high velocity, suggesting an origin from a highly disturbed medium, possibly an outflow. The line flux variability and broad widths are indicative of a jet that is, at least in part, responsible for the ionization of the BLR and NLR.
Cooke, Richard; Dahdah, Mary; Norman, Paul; French, David P
2016-06-01
This study aimed to quantify correlations between theory of planned behaviour (TPB) variables and (i) intentions to consume alcohol and (ii) alcohol consumption. Systematic literature searches identified 40 eligible studies that were meta-analysed. Three moderator analyses were conducted: pattern of consumption, gender of participants and age of participants. Across studies, intentions had the strongest relationship with attitudes (r+ = .62), followed by subjective norms (r+ = .47) and perceived behavioural control (PBC; r+ = .31). Self-efficacy (SE) had a stronger relationship with intentions (r+ = .48) compared with perceived control (PC; r+ = -.10). Intention had the strongest relationship with alcohol consumption (r+ = .54), followed by SE (r+ = .41). In contrast, PBC and PC had negative relationships with alcohol consumption (r+ = -.05 and -.13, respectively). All moderators affected TPB relationships. Patterns of consumption with clear definitions had stronger TPB relations, females reported stronger attitude-intention relations than males, and adults reported stronger attitude-intention and SE-intention relations than adolescents. Recommendations for future research include targeting attitudes and intentions in interventions to reduce alcohol consumption, using clear definitions of alcohol consumption in TPB items to improve prediction and assessing SE when investigating risk behaviours.
Cooke, Richard; Dahdah, Mary; Norman, Paul; French, David P.
2016-01-01
This study aimed to quantify correlations between theory of planned behaviour (TPB) variables and (i) intentions to consume alcohol and (ii) alcohol consumption. Systematic literature searches identified 40 eligible studies that were meta-analysed. Three moderator analyses were conducted: pattern of consumption, gender of participants and age of participants. Across studies, intentions had the strongest relationship with attitudes (r + = .62), followed by subjective norms (r + = .47) and perceived behavioural control (PBC; r + = .31). Self-efficacy (SE) had a stronger relationship with intentions (r + = .48) compared with perceived control (PC; r + = −.10). Intention had the strongest relationship with alcohol consumption (r + = .54), followed by SE (r + = .41). In contrast, PBC and PC had negative relationships with alcohol consumption (r + = −.05 and −.13, respectively). All moderators affected TPB relationships. Patterns of consumption with clear definitions had stronger TPB relations, females reported stronger attitude–intention relations than males, and adults reported stronger attitude–intention and SE–intention relations than adolescents. Recommendations for future research include targeting attitudes and intentions in interventions to reduce alcohol consumption, using clear definitions of alcohol consumption in TPB items to improve prediction and assessing SE when investigating risk behaviours. PMID:25089611
Genuino, Divine Angela D; de Luna, Mark Daniel G; Capareda, Sergio C
2018-02-01
Biochar produced from the slow pyrolysis of municipal solid waste was activated with KOH and thermal treatments to enhance its surface and adsorptive properties. The effects of KOH concentration, activation temperature and time on the specific surface area (SSA) of the activated biochar were evaluated and optimized using central composite design (CCD) of the response surface methodology (RSM). Results showed that the activation of biochar enhanced its SSA from 402.8 ± 12.5 to 662.4 ± 28.6 m 2 g -1 . The adsorptive capacities of the pristine biochar (PBC) and activated biochar (ABC) were compared using methylene blue (MB) dye as model compound. For MB concentrations up to 25 mg L -1 , more than 99% dye removal was achieved with ABC, while only a maximum of 51% was obtained with PBC. Results of the isotherm study showed that the Langmuir model best described MB adsorption on ABC with adsorption capacity of 37.0-41.2 mg g -1 . Copyright © 2017 Elsevier Ltd. All rights reserved.
Duncan, Michael J; Rivis, Amanda; Jordan, Caroline
2012-06-01
The aim of this brief report is to report on the utility of the Theory of Planned Behaviour (TPB) for predicting the physical activity intentions and behaviour of British adolescents from lower-than-average socio-economic backgrounds. A prospective questionnaire design was employed with 197, 13-14 year olds (76 males, 121 females). At time 1 participant completed standard measures of TPB variables. One week later (Time 2), participants completed the Physical Activity Questionnaire for Adolescents (PAQ-A) as a measure of physical activity behaviour. Hierarchical regression analyses showed that attitude and perceived behavioural control jointly accounted for 25% of the variance in intention (p = 0.0001). Perceived behavioural control emerged as the only significant predictor of physical activity behaviour and explained 3.7% of the variance (p = 0.001). Therefore, attitude and PBC successfully predicts intention towards physical activity and PBC predicts physical activity behaviour in British adolescents from lower-than-average socio-economic backgrounds. Copyright © 2011 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.
Using routinely gathered data to evaluate locally led service improvements.
Stoddart, Gilly; Gale, Robert; Peat, Chantelle; McInnes, Sarah
2011-07-01
Background Between 2009 and 2010 NHS Ealing tested the feasibility of a) combining data from more than one data-domain at the same time to quantify patient movement across the primary care/acute hospital boundary, and b) establishing online analyses so they can be constantly updated with near real-time data to compare different subsets of patients. The reports allowed us to see: changes in hospital admissions before and after referral to community matrons of patients with complex conditions from one practice-based commissioning (PBC) groupchanges in hospital bed-days of all patients from one practice or PBC group during a complex intervention designed to assist inter-disciplinary collaboration. Results The teams leading the projects found that the reports gave them confidence in the projects and helped to influence local policy. Discussion GP consortia need to evaluate complex service improvements in order to contain costs and improve quality. They will find such reports helpful to give ongoing feedback and this may help to keep people engaged. Present plans for data warehousing in London do not have this ability - they do not combine data from across the whole health economy, and are focused either on claims validation or risk stratification.
Ologeanu-Taddei, R; Morquin, D; Domingo, H; Bourret, R
2015-01-01
The goal of this study was to examine the perceived usefulness, the perceived ease of use and the perceived behavioral control of a Hospital Information System (HIS) for the care staff. We administrated a questionnaire composed of open-end and closed questions, based on the main concepts of Technology Acceptance Model. As results, the perceived usefulness, ease of use and behavioral control (self-efficacy and organizational support) are correlated with medical occupations. As an example, we found that a half of the medical secretaries consider the HIS is ease of use, at the opposite to the anesthesiologists, surgeons and physicians. Medical secretaries reported also the highest rate of PBC and a high rate of PU. Pharmacists reported the highest rate of PU but a low rate of PBC, which is similar to the rate of the surgeons and physicians. Content analysis of open questions highlights factors influencing these constructs: ergonomics, errors in the documenting process, insufficient compatibility with the medical department or the occupational group. Consequently, we suggest that the gap between the perceptions of the different occupational groups may be explained by the use of different modules and by interdependency of the care stare staff.
Piroxicam-β-Cyclodextrin: A GI Safer Piroxicam
Scarpignato, C
2013-01-01
Although NSAIDs are very effective drugs, their use is associated with a broad spectrum of adverse reactions in the liver, kidney, cardiovascular (CV) system, skin and gut. Gastrointestinal (GI) side effects are the most common and constitute a wide clinical spectrum ranging from dyspepsia, heartburn and abdominal discomfort to more serious events such as peptic ulcer with life-threatening complications of bleeding and perforation. The appreciation that CV risk is also increased further complicates the choices of physicians prescribing anti-inflammatory therapy. Despite prevention strategies should be implemented in patients at risk, gastroprotection is often underused and adherence to treatment is generally poor. A more appealing approach would be therefore to develop drugs that are devoid of or have reduced GI toxicity. Gastro-duodenal mucosa possesses many defensive mechanisms and NSAIDs have a deleterious effect on most of them. This results in a mucosa less able to cope with even a reduced acid load. NSAIDs cause gastro-duodenal damage, by two main mechanisms: a physiochemical disruption of the gastric mucosal barrier and systemic inhibition of gastric mucosal protection, through inhibition of cyclooxygenase (COX, PG endoperoxide G/H synthase) activity of the GI mucosa. However, against a background of COX inhibition by anti-inflammatory doses of NSAIDs, their physicochemical properties, in particular their acidity, underlie the topical effect leading to short-term damage. It has been shown that esterification of acidic NSAIDs suppresses their gastrotoxicity without adversely affecting anti-inflammatory activity. Another way to develop NSAIDs with better GI tolerability is to complex these molecules with cyclodextrins (CDs), giving rise to so-called “inclusion complexes” that can have physical, chemical and biological properties very different from either those of the drug or the cyclodextrin. Complexation of NSAIDs with β-cyclodextrin potentially leads to a more rapid onset of action after oral administration and improved GI tolerability because of minimization of the drug gastric effects. One such drug, piroxicam-β-cyclodextrin (PBC), has been used in Europe for 25 years. Preclinical and clinical pharmacology of PBC do show that the β-cyclodextrin inclusion complex of piroxicam is better tolerated from the upper GI tract than free piroxicam, while retaining all the analgesic and anti-inflammatory properties of the parent compound. In addition, the drug is endowed with a quick absorption rate, which translates into a faster onset of analgesic activity, an effect confirmed in several clinical studies. An analysis of the available trials show that PBC has a GI safety profile, which is better than that displayed by uncomplexed piroxicam. Being an inclusion complex of piroxicam, whose CV safety has been pointed out by several observational studies, PBC should be viewed as a CV safe anti-inflmmatory compound and a GI safer alternative to piroxicam. As a consequence, it should be considered as a useful addition to our therapeutic armamentarium. PMID:23394552
ERIC Educational Resources Information Center
Mahan, Sara; Matson, Johnny L.
2011-01-01
Many children with Autism Spectrum Disorder (ASD) demonstrate challenging behaviors. Since challenging behaviors are obstacles for social development and learning, it is important to determine if and what challenging behaviors are exhibited. Although there are some measures that asses for challenging behaviors, the majority were not specifically…
An Affymetrix Microarray Design for Microbial Genotyping
2009-10-01
sanguinis SK36 232 Streptococcus sanguinis HPT sanguinis 5 Streptococcus suis 05ZYH33 138 Streptococcus suis 98 HAH33 65 Streptococcus thermophilus...Rickettsia species, plasmids pBC16 and pLS1. Sequences representing bacterial toxins and antimicrobial resistance (e.g. antibiotic markers) were also...Also included were regions that were constant within a species but differed between species, virulence genes, and antibiotic resistance genes. 2.3
NASA Astrophysics Data System (ADS)
Mari, X.; Guinot, B. P.; Thuoc, C. V.; Brune, J.; Lefebvre, J. P.; Raimbault, P.; Niggemann, J.; Dittmar, T.
2016-02-01
Black Carbon (BC) is an aerosol emitted during biomass burning and fossil fuel combustion. The atmospheric lifetime of Black Carbon (BC) ranges from a few days in rainy climates up to one month in dry regions, and on a global scale wet deposition of atmospheric BC accounts for about 80% of the BC input to the ocean. The rain-mediated input of BC to the ocean was studied in a coastal site located in a regional hotspot of atmospheric BC concentration, North Vietnam. We monitored changes in atmospheric and marine BC during a 24-h cycle impacted by a short and heavy rainfall event. During the rainfall event, atmospheric BC concentration decreased by a factor of 8 (i.e. from 5230 to 660 µg BC m-3). This cleaning of the air column was immediately followed by a significant increase (by a factor of 2 to 4) of particulate BC (PBC) and POC concentrations in the surface microlayer (SML) and at 1.5 m depth. In the SML, this event was also followed by a significant increase of DOC and dissolved BC (DBC) concentrations. Interestingly, the concentration of DOC decreased by >10% after the rainfall at 1.5 m depth, suggesting an adsorption of DOC onto sinking PBC. Concomitantly with the increase in particulate BC, nutrient concentrations increased by a factor of 2 in the SML, while no change was observed in the underlying water column. After the rainfall, the particle size spectra, measured along the water column with a LISST (Laser In-Situ Scattering and Transmissometry probe), changed in that the concentration of small particles (<5 µm) decreased and the concentration of large particles (>100 µm) increased. This alteration of the particle size spectra was restricted to a thin layer of about 20 cm thickness, probably corresponding to a BC-enriched layer adsorbing DOC and small particles, and stimulating aggregation during sinking from the surface to deeper water layers. The concentrations of POC, DOC, PBC, DBC and nutrients reached pre-rainfall levels 4 hours after the event.
2014-01-01
Background Healthcare professionals (HCPs) are vital conduits of leisure-time physical activity (LTPA) information; however, few discuss LTPA with their patients with disabilities. ‘Changing Minds, Changing Lives’ (CMCL) is a nationwide, theory- and evidence-based seminar aimed at increasing LTPA-discussion among HCPs by enhancing their attitudes, subjective norms, perceived behavioural control (PBC), and intentions. The purposes of the current study were to: examine the effectiveness and short- and long-term maintenance of a CMCL seminar on HCPs’ social cognitions to discuss LTPA; and explore key implementation variables that predict changes in HCPs’ social cognitions. Methods Prior-to, as well as immediately, one, and six months following a CMCL seminar, 97 HCPs (Mage ± SD = 36.23 ± 10.42; 69.0% female; 97.9% Caucasian; 38.1% rehabilitation therapists; years in profession = 11.56 ± 9.94) from five Canadian provinces completed questionnaires that assessed the Theory of Planned Behaviour constructs with regard to discussing LTPA with their patients with a physical disability. Key presenter characteristics and intervention delivery components were extracted from presenter demographic questionnaires and seminar checklists, respectively. Separate repeated-measures ANOVAs and post-hoc t-tests evaluated changes in HCPs’ social cognitions. Hierarchical multiple regressions were conducted to predict intentions and to understand which implementation variables may help explain significant changes in social cognitions. Results Significant increases in HCPs’ social cognitions for discussing LTPA were reported from pre- to post-seminar (ps <0.002); however, increases were not maintained at follow-up. PBC emerged as the strongest predictor of participants’ post-CMCL intentions (β = 0.45, p <0.001). Although several implementation characteristics were related to changes in perceptions, the number of seminars the presenter delivered was the only significant negative predictor of post-seminar PBC (β = -0.18, p <0.05). Conclusions Future iterations of the CMCL intervention should include additional strategies to sustain improvements in HCPs’ social cognitions over time. Future CMCL evaluations should measure additional implementation variables so that the key ingredients for ‘Changing Minds’ can continue to be investigated. PMID:24581329
Gavaza, Paul; Brown, Carolyn M; Lawson, Kenneth A; Rascati, Karen L; Wilson, James P; Steinhardt, Mary
2011-12-01
Adverse drug event (ADE) reporting by pharmacists is an indispensable part of the drug safety system. U.S. pharmacists may submit reports of serious ADEs that they encounter to the Food and Drug Administration (FDA) through MedWatch. However, underreporting of serious ADEs is a common problem. Little is known about pharmacists' decision making with respect to ADE reporting. This study explored the utility of the theory of planned behavior (TPB) model in predicting Texas pharmacists' intention to report serious ADEs to the FDA. Data were collected from practicing Texas pharmacists using a mail questionnaire. A total of 1500 surveys were mailed, and 377 usable responses were obtained for a response rate of 26.4%. A majority (70.2%) of the 377 respondents were white/Caucasian, and 52.9% were male. Overall, pharmacists intended to report serious ADEs (mean=15.87±4.22; possible range: 3-21), had a positive attitude toward reporting (mean=4.62±4.92; possible range: -15 to +15), perceived that important others wanted them to report (subjective norm [SN] score=5.65±2.99; possible range: -9 to +9), and believed that they had control over their reporting behavior (perceived behavioral control [PBC] score=3.54±2.69; possible/actual range: -6 to +6). Attitude (β=0.221, P<.001) and SN (β=0.438, P<.001) significantly predicted intent; however, PBC (β=0.028, P>.05) did not. Attitude, SN, and PBC together accounted for 34.0% of the variance in intention to report serious ADEs (P<.001). The addition of past reporting behavior (P=.021) and perceived moral obligation (P<.001) significantly increased the variance in intention explained by the TPB model. Pharmacists showed a strong positive intent to report serious ADEs to the FDA. Strategies to increase pharmacists' intentions to report serious ADEs should focus on helping them see the value of reporting and altering their perception of social pressure toward reporting. The TPB may have utility in predicting ADE-reporting behavior. Copyright © 2011 Elsevier Inc. All rights reserved.
Comerford, Megan; Fogel, Rachel; Bailey, James Robert; Chilukuri, Prianka; Chalasani, Naga; Lammert, Craig Steven
2018-01-18
Conventional approaches to participant recruitment are often inadequate in rare disease investigation. Social networking sites such as Facebook may provide a vehicle to circumvent common research limitations and pitfalls. We report our preliminary experience with Facebook-based methodology for participant recruitment and participation into an ongoing study of autoimmune hepatitis (AIH). The goal of our research was to conduct a pilot study to assess whether a Facebook-based methodology is capable of recruiting geographically widespread participants into AIH patient-oriented research and obtaining quality phenotypic data. We established a Facebook community, the Autoimmune Hepatitis Research Network (AHRN), in 2014 to provide a secure and reputable distillation of current literature and AIH research opportunities. Quarterly advertisements for our ongoing observational AIH study were posted on the AHRN over 2 years. Interested and self-reported AIH participants were subsequently enrolled after review of study materials and completion of an informed consent by our study coordinator. Participants returned completed study materials, including epidemiologic questionnaires and genetic material, to our facility via mail. Outside medical records were obtained and reviewed by a study physician. We successfully obtained all study materials from 29 participants with self-reported AIH within 2 years from 20 different states. Liver biopsy results were available for 90% (26/29) of participants, of which 81% (21/29) had findings consistent with AIH, 15% (4/29) were suggestive of AIH with features of primary biliary cholangitis (PBC), and 4% (1/29) had PBC alone. A total of 83% (24/29) had at least 2 of 3 proposed criteria: positive autoimmune markers, consistent histologic findings of AIH on liver biopsy, and reported treatment with immunosuppressant medications. Self-reported and physician records were discrepant for immunosuppressant medications or for AIH/PBC diagnoses in 4 patients. Facebook can be an effective ancillary tool for facilitating patient-oriented research in rare diseases. A social media-based approach transcends established limitations in rare disease research and can further develop research communities. ©Megan Comerford, Rachel Fogel, James Robert Bailey, Prianka Chilukuri, Naga Chalasani, Craig Steven Lammert. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 18.01.2018.
Bailey, James Robert; Chilukuri, Prianka; Chalasani, Naga
2018-01-01
Background Conventional approaches to participant recruitment are often inadequate in rare disease investigation. Social networking sites such as Facebook may provide a vehicle to circumvent common research limitations and pitfalls. We report our preliminary experience with Facebook-based methodology for participant recruitment and participation into an ongoing study of autoimmune hepatitis (AIH). Objective The goal of our research was to conduct a pilot study to assess whether a Facebook-based methodology is capable of recruiting geographically widespread participants into AIH patient-oriented research and obtaining quality phenotypic data. Methods We established a Facebook community, the Autoimmune Hepatitis Research Network (AHRN), in 2014 to provide a secure and reputable distillation of current literature and AIH research opportunities. Quarterly advertisements for our ongoing observational AIH study were posted on the AHRN over 2 years. Interested and self-reported AIH participants were subsequently enrolled after review of study materials and completion of an informed consent by our study coordinator. Participants returned completed study materials, including epidemiologic questionnaires and genetic material, to our facility via mail. Outside medical records were obtained and reviewed by a study physician. Results We successfully obtained all study materials from 29 participants with self-reported AIH within 2 years from 20 different states. Liver biopsy results were available for 90% (26/29) of participants, of which 81% (21/29) had findings consistent with AIH, 15% (4/29) were suggestive of AIH with features of primary biliary cholangitis (PBC), and 4% (1/29) had PBC alone. A total of 83% (24/29) had at least 2 of 3 proposed criteria: positive autoimmune markers, consistent histologic findings of AIH on liver biopsy, and reported treatment with immunosuppressant medications. Self-reported and physician records were discrepant for immunosuppressant medications or for AIH/PBC diagnoses in 4 patients. Conclusions Facebook can be an effective ancillary tool for facilitating patient-oriented research in rare diseases. A social media-based approach transcends established limitations in rare disease research and can further develop research communities. PMID:29348111
Guo, Guangjun; Wang, Shubin; Liu, Jinbing; Pan, Baogui; Diao, Weiping; Ge, Wei; Gao, Changzhou; Snyder, John C
2017-01-01
Next-generation sequencing enabled a fast discovery of QTLs controlling CMV resistant in pepper. The gene CA02g19570 as a possible candidate gene of qCmr2.1 was identified for resistance to CMV in pepper. Cucumber mosaic virus (CMV) is one of the most important viruses infecting pepper, but the genetic basis of CMV resistance in pepper is elusive. In this study, we identified a candidate gene for CMV resistance QTL, qCmr2.1 through SLAF-seq. Segregation analysis in F 2 , BC 1 and F 2:3 populations derived from a cross between two inbred lines 'PBC688' (CMV-resistant) and 'G29' (CMV-susceptible) suggested quantitative inheritance of resistance to CMV in pepper. Genome-wide comparison of SNP profiles between the CMV-resistant and CMV-susceptible bulks constructed from an F 2 population identified two QTLs, designated as qCmr2.1 on chromosome 2 and qCmr11.1 on chromosome 11 for resistance to CMV in PBC688, which were confirmed by InDel marker-based classical QTL mapping in the F 2 population. As a major QTL, joint SLAF-seq and traditional QTL analysis delimited qCmr2.1 to a 330 kb genomic region. Two pepper genes, CA02g19570 and CA02g19600, were identified in this region, which are homologous with the genes LOC104113703, LOC104248995, LOC102603934 and LOC101248357, which were predicted to encode N-like protein associated with TMV-resistant in Solanum crops. Quantitative RT-PCR revealed higher expression levels of CA02g19570 in CMV resistance genotypes. The CA02g19600 did not exhibit obvious regularity in expression patterns. Higher relative expression levels of CA02g19570 in PBC688 and F 1 were compared with those in G29 during days after inoculation. These results provide support for CA02g19570 as a possible candidate gene of qCmr2.1 for resistance to CMV in pepper.
Petraco, Ricardo; Dehbi, Hakim-Moulay; Howard, James P; Shun-Shin, Matthew J; Sen, Sayan; Nijjer, Sukhjinder S; Mayet, Jamil; Davies, Justin E; Francis, Darrel P
2018-01-01
Diagnostic accuracy is widely accepted by researchers and clinicians as an optimal expression of a test's performance. The aim of this study was to evaluate the effects of disease severity distribution on values of diagnostic accuracy as well as propose a sample-independent methodology to calculate and display accuracy of diagnostic tests. We evaluated the diagnostic relationship between two hypothetical methods to measure serum cholesterol (Chol rapid and Chol gold ) by generating samples with statistical software and (1) keeping the numerical relationship between methods unchanged and (2) changing the distribution of cholesterol values. Metrics of categorical agreement were calculated (accuracy, sensitivity and specificity). Finally, a novel methodology to display and calculate accuracy values was presented (the V-plot of accuracies). No single value of diagnostic accuracy can be used to describe the relationship between tests, as accuracy is a metric heavily affected by the underlying sample distribution. Our novel proposed methodology, the V-plot of accuracies, can be used as a sample-independent measure of a test performance against a reference gold standard.
ERIC Educational Resources Information Center
Matson, Johnny L.; Mahan, Sara; Hess, Julie A.; Fodstad, Jill C.; Neal, Daniene
2010-01-01
This study examined the effect of age on challenging behaviors among 167 children, ages 3-14 years, with Autistic Disorder, Pervasive Developmental Disorder Not Otherwise Specified, or Asperger's syndrome. Results of a MANOVA indicated that there were no significant differences between young children, children, and young adolescents on any of the…
ERIC Educational Resources Information Center
Al-Haija, Qasem Abu; Al-Amri, Hasan; Al-Nashri, Mohamed; Al-Muhaisen, Sultan
2013-01-01
Project-Based Curriculum (PBC) is considered one of the most powerful methods in the engineering education where each course or courses-cluster is assigned a design project which considers a series of inter-related concepts that have been shown theoretically for the students. Using this approach, the student will gain the required knowledge in an…
Primary biliary cirrhosis: From bench to bedside
Kouroumalis, Elias; Notas, George
2015-01-01
Primary biliary cirrhosis (PBC) is a chronic non-suppurative destructive intrahepatic cholangitis leading to cirrhosis after a protractive non cirrhotic stage. The etiology and pathogenesis are largely unknown and autoimmne mechanisms have been implicated to explain the pathological lesions. Many epitopes and autoantigens have been reported as crucial in the pathophysiology of the disease and T and B cells abnormalities have been described, the exact pathways leading to the destruction of small intrahepatic ductules are mostly speculative. In this review we examined the various epidemiologal and geoepidemiological data as well as the complex pathogenetic aspects of this disease, focusing on recent in vivo and in vitro studies in this field. Initiation and progression of PBC is believed to be a multifactorial process with strong infuences from the patient’s genetic background and by various environmental factors. The role of innate and adaptive immunity, including cytokines, chemokines, macrophages and the involvement of apoptosis and reactive oxygen species are outlined in detailed. The current pathogenetic aspects are presented and a novel pathogenetic theory unifying the accumulated clinical information with in vitro and in vivo data is formulated. A review of clinical manifestations and immunological and pathological diagnosis was presented. Treatment modalities, including the multiple mechanisms of action of ursodeoxycholate were finally discussed. PMID:26261733
Searching for New γ-Ray Blazar Candidates in the Third Palermo BAT Hard X-Ray Catalog with WISE
NASA Astrophysics Data System (ADS)
Maselli, A.; Massaro, F.; Cusumano, G.; D'Abrusco, R.; La Parola, V.; Paggi, A.; Segreto, A.; Smith, Howard A.; Tosti, G.
2013-06-01
We searched for γ-ray blazar candidates among the 382 unidentified hard X-ray sources of the third Palermo BAT Catalog (3PBC) obtained from the analysis of 66 months of Swift Burst Alert Telescope (BAT) survey data and listing 1586 sources. We adopted a recently developed association method based on the peculiar infrared colors that characterize the γ-ray blazars included in the second catalog of active galactic nuclei detected by the Fermi Large Area Telescope. We used this method exploiting the data of the all-sky survey performed by the Wide-field Infrared Survey Explorer (WISE) to establish correspondences between unidentified 3PBC sources and WISE γ-ray blazar candidates located within the BAT positional uncertainty region at a 99% confidence level. We obtained a preliminary list of candidates for which we analyzed all the available data in the Swift archive to complement the information in the literature and in the radio, infrared, and optical catalogs with the information on their optical-UV and soft X-ray emission. Requiring the presence of radio and soft X-ray counterparts consistent with the infrared positions of the selected WISE sources, as well as a blazar-like radio morphology, we finally obtained a list of 24 γ-ray blazar candidates.
Identifying Psychosocial Variables That Predict Safer Sex Intentions in Adolescents and Young Adults
Brüll, Phil; Ruiter, Robert A. C.; Wiers, Reinout W.; Kok, Gerjo
2016-01-01
Young people are especially vulnerable to sexually transmitted infections (STIs). The triad of deliberate and effective safer sex behavior encompasses condom use, combined with additional information about a partner’s sexual health, and the kind of sex acts usually performed. To identify psychosocial predictors of young people’s intentions to have safer sex, as related to this triad, we conducted an online study with 211 sexually active participants aged between 18 and 24 years. Predictors [i.e., perceived behavioral control (PBC), subjective norms, and intention] taken from Fishbein and Ajzen’s Reasoned Action Approach (RAA), were combined with more distal variables (e.g., behavioral inhibition, sensation seeking, parental monitoring, and knowledge about STIs). Beyond the highly predictive power of RAA variables, additional variance was explained by the number of instances of unprotected sexual intercourse (SI) during the last 12 months and reasons for using barrier protection during first SI. In particular, past condom non-use behavior moderated PBC related to intended condom use. Further, various distal variables showed significant univariate associations with intentions related to the three behaviors of interest. It may, therefore, be helpful to include measures of past behavior as well as certain additional distal variables in future safer sex programs designed to promote health-sustaining sexual behavior. PMID:27148520
Purchasing habits of senior farmers' market shoppers: utilizing the theory of planned behavior.
Middleton, Crystal; Smith, Sylvia
2011-01-01
The purpose of this study was to understand fresh fruit and vegetable purchasing habits among senior farmers' market shoppers using the theory of planned behavior. A survey instrument was developed to collect information on seniors' fruit and vegetable purchasing habits. A convenience sample of seniors shopping at farmers' markets was employed. A total of 184 surveys were collected. Respondents were divided into two groups based on response to a question of whether they received Senior Farmers' Market Nutritional Program (SFMNP) checks: 35 were on the SFMNP and 149 were not. Results indicated attitudes, subjective norms (SN), and perceived behavioral control (PBC) were all significantly correlated with intentions at the p < 0.01 level. Attitude had the strongest association with intentions (0.730), followed by PBC (0.666) and SN (0.587). Regression analysis was significant and explained 66% of the variance (F = 86.151, p < 0.001, adjusted R square = 0.656). Results indicated attitude to be the strongest predictor of seniors' intentions to purchase more fresh fruits and vegetables at farmers' markets. Senior programs may find this information useful when promoting fresh fruits and vegetables for senior citizens. These findings may also benefit farmers' markets while promoting fresh fruits and vegetables.
Psychological predictors of cultural diversity support at work.
Hiemstra, Annemarie M F; Derous, Eva; Born, Marise Ph
2017-07-01
As diversity management activities become more prominent worldwide it is important to understand psychological reactions to them to ensure success, but empirical evidence is lacking. This study investigated employees' and managers' intentions and behavior to promote cultural diversity at work in a variety of organizations in the Netherlands, using Ajzen's theory of planned behavior. Predictors of intentions to promote cultural diversity at work (N = 670) and actual behavior after 6 months were assessed among managers and employees using self-reports in a 2-wave survey design. Participants' average age at Time 1 was 38.26 years (SD = 11.86), 56% was female, and there were 78.1% Dutch ethnic majority and 21.9% ethnic minority participants. Attitude to cultural diversity promotion at work and perceived behavioral control (PBC) related positively to both individuals' intentions to promote cultural diversity at work, which in turn predicted behavior. The strongest driver, however, was attitude. Managers' reported PBC and behavior were higher compared to employees. This study supported the applicability of the theory of planned behavior to predict intentions and behavior to promote cultural diversity at work. With an increasingly diverse workforce, this study aimed to advance our understanding of drivers of individual reactions and behavior to support cultural diversity at work. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
McCormack, Gavin R; Friedenreich, Christine M; Giles-Corti, Billie; Doyle-Baker, Patricia K; Shiell, Alan
2013-09-01
The built and social environments may contribute to physical activity motivations and behavior. We examined the extent to which the Theory of Planned Behavior (TPB) mediated the association between neighborhood walkability and walking. Two random cross-sectional samples (n = 4422 adults) completed telephone interviews capturing walking-related TPB variables (perceived behavioral control (PBC), attitudes, subjective norm, intention). Of those, 2006 completed a self-administered questionnaire capturing walkability, social support (friends, family, dog ownership), and neighborhood-based transportation (NTW) and recreational walking (NRW). The likelihood of undertaking 1) any vs. none and 2) sufficient vs. insufficient levels (≥150 vs. <150 minutes/week) of NTW and NWR, in relation to walkability, social support, and TPB was estimated. Any and sufficient NTW were associated with access to services, connectivity, residential density, not owning a dog (any NTW only), and friend and family support. Any and sufficient NRW were associated with neighborhood aesthetics (any NRW only), dog ownership, and friend and family support. PBC partially mediated the association between access to services and NTW (any and sufficient), while experiential attitudes partially mediated the association between neighborhood aesthetics and any NRW. Interventions that increase positive perceptions of the built environment may motivate adults to undertake more walking.
Peleg, Shira; Vilchinsky, Noa; Fisher, William A; Khaskia, Abed; Mosseri, Morris
2017-12-01
To achieve a comprehensive understanding of patients' adherence to medication following acute coronary syndrome (ACS), we assessed the possible moderating role played by attachment orientation on the effects of attitudes, subjective norms, and perceived behavioral control (PBC), as derived from the Theory of Planned Behavior (TPB; Ajzen, 1991), on intention and reported adherence. A prospective longitudinal design was employed. During hospitalization, ACS male patients (N = 106) completed a set of self-report questionnaires including sociodemographic variables, attachment orientation, and measures of TPB constructs. Six months post-discharge, 90 participants completed a questionnaire measuring adherence to medication. Attachment orientations moderated some of the predictions of the TPB model. PBC predicted intention and reported adherence, but these associations were found to be significant only among individuals with lower, as opposed to higher, attachment anxiety. The association between attitudes and intention was stronger among individuals with higher, as opposed to lower, attachment anxiety. Only among individuals with higher attachment avoidance, subjective norms were negatively associated with intention to take medication. Cognitive variables appear to explain both adherence intention and behavior, but differently, depending on individuals' attachment orientations. Integrating personality and cognitive models may prove effective in understanding patients' health behaviors. © 2016 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Jogenfors, Jonathan; Larsson, Jan-Åke
2017-08-01
In any Bell test, loopholes can cause issues in the interpretation of the results, since an apparent violation of the inequality may not correspond to a violation of local realism. An important example is the coincidence-time loophole that arises when detector settings might influence the time when detection will occur. This effect can be observed in many experiments where measurement outcomes are to be compared between remote stations because the interpretation of an ostensible Bell violation strongly depends on the method used to decide coincidence. The coincidence-time loophole has previously been studied for the Clauser-Horne-Shimony-Holt and Clauser-Horne inequalities, but recent experiments have shown the need for a generalization. Here, we study the generalized "chained" inequality by Pearle, Braunstein, and Caves (PBC) with N ≥2 settings per observer. This inequality has applications in, for instance, quantum key distribution where it has been used to reestablish security. In this paper we give the minimum coincidence probability for the PBC inequality for all N ≥2 and show that this bound is tight for a violation free of the fair-coincidence assumption. Thus, if an experiment has a coincidence probability exceeding the critical value derived here, the coincidence-time loophole is eliminated.
Kothe, E J; Mullan, B A; Butow, P
2012-06-01
This study evaluated the efficacy of a theory of planned behaviour (TPB) based intervention to increase fruit and vegetable consumption. The extent to which fruit and vegetable consumption and change in intake could be explained by the TPB was also examined. Participants were randomly assigned to two levels of intervention frequency matched for intervention content (low frequency n=92, high frequency n=102). Participants received TPB-based email messages designed to increase fruit and vegetable consumption, messages targeted attitude, subjective norm and perceived behavioural control (PBC). Baseline and post-intervention measures of TPB variables and behaviour were collected. Across the entire study cohort, fruit and vegetable consumption increased by 0.83 servings/day between baseline and follow-up. Intention, attitude, subjective norm and PBC also increased (p<.05). The TPB successfully modelled fruit and vegetable consumption at both time points but not behaviour change. The increase of fruit and vegetable consumption is a promising preliminary finding for those primarily interested in increasing fruit and vegetable consumption. However, those interested in theory development may have concerns about the use of this model to explain behaviour change in this context. More high quality experimental tests of the theory are needed to confirm this result. Copyright © 2012 Elsevier Ltd. All rights reserved.
Primary biliary cirrhosis-specific antimitochondrial antibodies in neonatal haemochromatosis.
Smyk, Daniel S; Mytilinaiou, Maria G; Grammatikopoulos, Tassos; Knisely, A S; Mieli-Vergani, Giorgina; Bogdanos, Dimitrios P; Vergani, Diego
2013-01-01
Neonatal hemochromatosis (NH) is characterised by severe liver injury and extrahepatic siderosis sparing the reticuloendothelial system. Its aetiology is obscure, although it has been proposed as an alloimmune disease, resulting from immunological reaction to self-antigens (alloantigens) which the body recognizes as foreign. We studied an infant with NH and his mother whose sera contained antimitochondrial antibody (AMA), the hallmark of primary biliary cirrhosis (PBC). To investigate the origin of AMA in the infant, we studied isotype distributions in serum from the mother and infant. Serum samples were obtained at diagnosis of NH, after liver transplantation (LT; age 1 month), and over the ensuing 17 months. At NH diagnosis, infant and maternal serum contained AMA of the IgG isotype, predominantly of the G3 and G1 subclasses. AMA strongly reacted against the pyruvate dehydrogenase complex E2 subunit (PDC-E2), the major PBC-specific AMA autoantigen. Anti-PDC-E2 responses in both infant and mother declined over time, being present 2 months after LT (mother and child) and absent 10 months later (mother) and 17 months later (child). The association of maternally transferred IgG1 and IgG3 subclass AMA with the appearance of liver damage in an infant with NH may suggest a causal link between antibody and liver damage.
Fernandes-Machado, Sandra; Gellert, Paul; Goncalves, Sonia; Sniehotta, Falko F; Araujo-Soares, Vera
2016-10-01
There are currently no instruments available to measure social cognitions towards food choice in children. This study aimed to test the feasibility and predictive validity of a novel measurement tool to assess food-related social cognitions. Sixty-eight children, five to eight years old, were asked to sort cards with photographs of four fruit and four sweet/savoury snacks as a mean to measure attitudes, subjective norms, perceived behavioural control (PBC), and intention. Subsequently, food choice (dependent variable) was assessed using a laboratory food choice task in which children could gain access to sweet and savoury or fruit items, or a combination. All participants completed the tasks successfully, demonstrating feasibility of the procedure. The order in which the cards were sorted for each construct differed sufficiently and correlations between constructs were in line with previous studies. Measures of PBC, intention, attitude, and subjective norm from the mother, but not from teachers or friends, correlated significantly with subsequent food choice. It is possible to measure food-related social cognitions in children aged five to eight and these measures were predictive of observed behaviour. The new instrument can contribute to our understanding of psychological determinants of food choice in young children. Copyright © 2016 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xiong, Yongliang; Kirkes, Leslie Dawn; Westfall, Terry
For this study, the interactions of lead with citrate and ethylenediaminetetraacetate (EDTA) are investigated based on solubility measurements as a function of ionic strength at room temperature (22.5 ± 0.5°C) in NaCl and M gCl 2 solutions. The formation constants (log β 1 0 ) for Pb[C 3H 5O(COO) 3]– (abbreviated as PbCitrate –) and Pb[(CH 2COO) 2N(CH2) 2N(CH 2COO) 2)] 2– (abbreviated as PbEDTA 2–) Pb 2+ + [C 3H 5O(COO) 3] 3– = Pb[C 3H 5O(COO) 3] – (1) Pb 2+ + (CH 2COO) 2N(CH 2) 2N(CH 2COO) 2) 4- = Pb[(CH 2COO) 2N(CH 2) 2N(CH 2COO) 2)]more » 2– (2) are evaluated as 7.28 ± 0.18 (2σ) and 20.00 ± 0.20 (2σ), respectively, with a set of Pitzer parameters describing the specific interactions in NaCl and M gCl 2 media. Based on these parameters, the interactions of lead with citrate and EDTA in various low temperature environments can be accurately modelled.« less
Quinn, Francis; Johnston, Marie; Johnston, Derek W
2013-01-01
Previous research has supported an integrated biomedical and behavioural model explaining activity limitations. However, further tests of this model are required at the within-person level, because while it proposes that the constructs are related within individuals, it has primarily been tested between individuals in large group studies. We aimed to test the integrated model at the within-person level. Six correlational N-of-1 studies in participants with arthritis, chronic pain and walking limitations were carried out. Daily measures of theoretical constructs were collected using a hand-held computer (PDA), the activity was assessed by self-report and accelerometer and the data were analysed using time-series analysis. The biomedical model was not supported as pain impairment did not predict activity, so the integrated model was supported partially. Impairment predicted intention to move around, while perceived behavioural control (PBC) and intention predicted activity. PBC did not predict activity limitation in the expected direction. The integrated model of disability was partially supported within individuals, especially the behavioural elements. However, results suggest that different elements of the model may drive activity (limitations) for different individuals. The integrated model provides a useful framework for understanding disability and suggests interventions, and the utility of N-of-1 methodology for testing theory is illustrated.
SU-F-T-441: Dose Calculation Accuracy in CT Images Reconstructed with Artifact Reduction Algorithm
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ng, C; Chan, S; Lee, F
Purpose: Accuracy of radiotherapy dose calculation in patients with surgical implants is complicated by two factors. First is the accuracy of CT number, second is the dose calculation accuracy. We compared measured dose with dose calculated on CT images reconstructed with FBP and an artifact reduction algorithm (OMAR, Philips) for a phantom with high density inserts. Dose calculation were done with Varian AAA and AcurosXB. Methods: A phantom was constructed with solid water in which 2 titanium or stainless steel rods could be inserted. The phantom was scanned with the Philips Brillance Big Bore CT. Image reconstruction was done withmore » FBP and OMAR. Two 6 MV single field photon plans were constructed for each phantom. Radiochromic films were placed at different locations to measure the dose deposited. One plan has normal incidence on the titanium/steel rods. In the second plan, the beam is at almost glancing incidence on the metal rods. Measurements were then compared with dose calculated with AAA and AcurosXB. Results: The use of OMAR images slightly improved the dose calculation accuracy. The agreement between measured and calculated dose was best with AXB and image reconstructed with OMAR. Dose calculated on titanium phantom has better agreement with measurement. Large discrepancies were seen at points directly above and below the high density inserts. Both AAA and AXB underestimated the dose directly above the metal surface, while overestimated the dose below the metal surface. Doses measured downstream of metal were all within 3% of calculated values. Conclusion: When doing treatment planning for patients with metal implants, care must be taken to acquire correct CT images to improve dose calculation accuracy. Moreover, great discrepancies in measured and calculated dose were observed at metal/tissue interface. Care must be taken in estimating the dose in critical structures that come into contact with metals.« less
Dehbi, Hakim-Moulay; Howard, James P; Shun-Shin, Matthew J; Sen, Sayan; Nijjer, Sukhjinder S; Mayet, Jamil; Davies, Justin E; Francis, Darrel P
2018-01-01
Background Diagnostic accuracy is widely accepted by researchers and clinicians as an optimal expression of a test’s performance. The aim of this study was to evaluate the effects of disease severity distribution on values of diagnostic accuracy as well as propose a sample-independent methodology to calculate and display accuracy of diagnostic tests. Methods and findings We evaluated the diagnostic relationship between two hypothetical methods to measure serum cholesterol (Cholrapid and Cholgold) by generating samples with statistical software and (1) keeping the numerical relationship between methods unchanged and (2) changing the distribution of cholesterol values. Metrics of categorical agreement were calculated (accuracy, sensitivity and specificity). Finally, a novel methodology to display and calculate accuracy values was presented (the V-plot of accuracies). Conclusion No single value of diagnostic accuracy can be used to describe the relationship between tests, as accuracy is a metric heavily affected by the underlying sample distribution. Our novel proposed methodology, the V-plot of accuracies, can be used as a sample-independent measure of a test performance against a reference gold standard. PMID:29387424
1997-09-01
Policy Implications Stephen D. Biddle, IDA Papaer P-3123 Institute for Defense Analysis (IDA), Strategy Forces and Research Division 1801 N...IDA INSTITUTE FOR DEFENSE ANALYSES Information Operations: A Research Aid Includes Coverage of: Information Warfare, Information Assurance...Gray, Principal Investigator [pBC Q^^E^ nsSSPECTBD 8’ 19980303 031 This work was conducted under IDA’S central research program. The publication of
ERIC Educational Resources Information Center
Park, Hee Sun; Smith, Sandi W.
2007-01-01
The effects of the attitudinal, normative, and perceived behavioral control (PBC) components of the theory of planned behavior and personal- and societal-level descriptive and injunctive norms were investigated with regard to their impact on the intent to enroll on a state organ-donor registry and the intent to engage in family discussion about…
Approaches to reducing photon dose calculation errors near metal implants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huang, Jessie Y.; Followill, David S.; Howell, Reb
Purpose: Dose calculation errors near metal implants are caused by limitations of the dose calculation algorithm in modeling tissue/metal interface effects as well as density assignment errors caused by imaging artifacts. The purpose of this study was to investigate two strategies for reducing dose calculation errors near metal implants: implementation of metal-based energy deposition kernels in the convolution/superposition (C/S) dose calculation method and use of metal artifact reduction methods for computed tomography (CT) imaging. Methods: Both error reduction strategies were investigated using a simple geometric slab phantom with a rectangular metal insert (composed of titanium or Cerrobend), as well asmore » two anthropomorphic phantoms (one with spinal hardware and one with dental fillings), designed to mimic relevant clinical scenarios. To assess the dosimetric impact of metal kernels, the authors implemented titanium and silver kernels in a commercial collapsed cone C/S algorithm. To assess the impact of CT metal artifact reduction methods, the authors performed dose calculations using baseline imaging techniques (uncorrected 120 kVp imaging) and three commercial metal artifact reduction methods: Philips Healthcare’s O-MAR, GE Healthcare’s monochromatic gemstone spectral imaging (GSI) using dual-energy CT, and GSI with metal artifact reduction software (MARS) applied. For the simple geometric phantom, radiochromic film was used to measure dose upstream and downstream of metal inserts. For the anthropomorphic phantoms, ion chambers and radiochromic film were used to quantify the benefit of the error reduction strategies. Results: Metal kernels did not universally improve accuracy but rather resulted in better accuracy upstream of metal implants and decreased accuracy directly downstream. For the clinical cases (spinal hardware and dental fillings), metal kernels had very little impact on the dose calculation accuracy (<1.0%). Of the commercial CT artifact reduction methods investigated, the authors found that O-MAR was the most consistent method, resulting in either improved dose calculation accuracy (dental case) or little impact on calculation accuracy (spine case). GSI was unsuccessful at reducing the severe artifacts caused by dental fillings and had very little impact on calculation accuracy. GSI with MARS on the other hand gave mixed results, sometimes introducing metal distortion and increasing calculation errors (titanium rectangular implant and titanium spinal hardware) but other times very successfully reducing artifacts (Cerrobend rectangular implant and dental fillings). Conclusions: Though successful at improving dose calculation accuracy upstream of metal implants, metal kernels were not found to substantially improve accuracy for clinical cases. Of the commercial artifact reduction methods investigated, O-MAR was found to be the most consistent candidate for all-purpose CT simulation imaging. The MARS algorithm for GSI should be used with caution for titanium implants, larger implants, and implants located near heterogeneities as it can distort the size and shape of implants and increase calculation errors.« less
The Enigmatic Cornea and Intraocular Lens Calculations: The LXXIII Edward Jackson Memorial Lecture.
Koch, Douglas D
2016-11-01
To review the progress and challenges in obtaining accurate corneal power measurements for intraocular lens (IOL) calculations. Personal perspective, review of literature, case presentations, and personal data. Through literature review findings, case presentations, and data from the author's center, the types of corneal measurement errors that can occur in IOL calculation are categorized and described, along with discussion of future options to improve accuracy. Advances in IOL calculation technology and formulas have greatly increased the accuracy of IOL calculations. Recent reports suggest that over 90% of normal eyes implanted with IOLs may achieve accuracy to within 0.5 diopter (D) of the refractive target. Though errors in estimation of corneal power can cause IOL calculation errors in eyes with normal corneas, greater difficulties in measuring corneal power are encountered in eyes with diseased, scarred, and postsurgical corneas. For these corneas, problematic issues are quantifying anterior corneal power and measuring posterior corneal power and astigmatism. Results in these eyes are improving, but 2 examples illustrate current limitations: (1) spherical accuracy within 0.5 D is achieved in only 70% of eyes with post-refractive surgery corneas, and (2) astigmatism accuracy within 0.5 D is achieved in only 80% of eyes implanted with toric IOLs. Corneal power measurements are a major source of error in IOL calculations. New corneal imaging technology and IOL calculation formulas have improved outcomes and hold the promise of ongoing progress. Copyright © 2016 Elsevier Inc. All rights reserved.
Carver, Robert L; Sprunger, Conrad P; Hogstrom, Kenneth R; Popple, Richard A; Antolak, John A
2016-05-08
The purpose of this study was to evaluate the accuracy and calculation speed of electron dose distributions calculated by the Eclipse electron Monte Carlo (eMC) algorithm for use with bolus electron conformal therapy (ECT). The recent com-mercial availability of bolus ECT technology requires further validation of the eMC dose calculation algorithm. eMC-calculated electron dose distributions for bolus ECT have been compared to previously measured TLD-dose points throughout patient-based cylindrical phantoms (retromolar trigone and nose), whose axial cross sections were based on the mid-PTV (planning treatment volume) CT anatomy. The phantoms consisted of SR4 muscle substitute, SR4 bone substitute, and air. The treatment plans were imported into the Eclipse treatment planning system, and electron dose distributions calculated using 1% and < 0.2% statistical uncertainties. The accuracy of the dose calculations using moderate smoothing and no smooth-ing were evaluated. Dose differences (eMC-calculated less measured dose) were evaluated in terms of absolute dose difference, where 100% equals the given dose, as well as distance to agreement (DTA). Dose calculations were also evaluated for calculation speed. Results from the eMC for the retromolar trigone phantom using 1% statistical uncertainty without smoothing showed calculated dose at 89% (41/46) of the measured TLD-dose points was within 3% dose difference or 3 mm DTA of the measured value. The average dose difference was -0.21%, and the net standard deviation was 2.32%. Differences as large as 3.7% occurred immediately distal to the mandible bone. Results for the nose phantom, using 1% statistical uncertainty without smoothing, showed calculated dose at 93% (53/57) of the measured TLD-dose points within 3% dose difference or 3 mm DTA. The average dose difference was 1.08%, and the net standard deviation was 3.17%. Differences as large as 10% occurred lateral to the nasal air cavities. Including smoothing had insignificant effects on the accuracy of the retromolar trigone phantom calculations, but reduced the accuracy of the nose phantom calculations in the high-gradient dose areas. Dose calculation times with 1% statistical uncertainty for the retromolar trigone and nose treatment plans were 30 s and 24 s, respectively, using 16 processors (Intel Xeon E5-2690, 2.9 GHz) on a framework agent server (FAS). In comparison, the eMC was significantly more accurate than the pencil beam algorithm (PBA). The eMC has comparable accuracy to the pencil beam redefinition algorithm (PBRA) used for bolus ECT planning and has acceptably low dose calculation times. The eMC accuracy decreased when smoothing was used in high-gradient dose regions. The eMC accuracy was consistent with that previously reported for accuracy of the eMC electron dose algorithm and shows that the algorithm is suitable for clinical implementation of bolus ECT.
In the Right Ballpark? Assessing the Accuracy of Net Price Calculators
ERIC Educational Resources Information Center
Anthony, Aaron M.; Page, Lindsay C.; Seldin, Abigail
2016-01-01
Large differences often exist between a college's sticker price and net price after accounting for financial aid. Net price calculators (NPCs) were designed to help students more accurately estimate their actual costs to attend a given college. This study assesses the accuracy of information provided by net price calculators. Specifically, we…
Takeshita, Takashi; Yamamoto, Yutaka; Yamamoto-Ibusuki, Mutsuko; Tomiguchi, Mai; Sueta, Aiko; Murakami, Keiichi; Iwase, Hirotaka
2018-02-26
The somatic activation of PI3K/AKT pathway mutations, PIK3CA and AKT1, and ESR1 mutations in plasma cell-free DNA (cfDNA) has been studied as a non-invasive procedure to quickly assess and monitor disease progression or therapeutic effect in breast cancer (BC) patients, but the clinical significance of these mutations in late treatment lines (TLs) remains unclear. The subjects of this study were a total of 251 plasma samples from 128 estrogen receptor-positive (ER+) BC patients. Of these plasma samples, 133 were from 73 primary BC (PBC) patients, and 118 plasma samples were from 68 metastatic BC (MBC) patients. We developed droplet digital PCR (ddPCR) assays to verify the clinical significance of PIK3CA, AKT1, and ESR1 mutations in these patients. cfDNA PIK3CA mutations were observed in 15.1% of the PBC patients, while a cfDNA AKT1 mutation was observed in 1.4% of patients, and cfDNA ESR1 mutations were observed in 2.7% of patients. Patients with detectable cfDNA PIK3CA mutations were not associated with clinical outcomes. According to the TL, the prevalence of the PIK3CA and ESR1 mutations in cfDNA were lower in early TLs compared with late TLs. In the early TL group, patients with cfDNA PIK3CA mutations had a shorter time to treatment failure (TTF) than patients without mutations (P = 0.035). However, there was no statistically significant difference between patients with or without cfDNA ESR1 mutations. However, in the late TL group, patients with cfDNA ESR1 mutations had a shorter TTF than patients without mutations (P = 0.048). However, there was no statistically significant difference between patients with or without cfDNA PIK3CA mutations. Since the prevalence of cfDNA AKT1 mutation is low in both PBC and MBC patients, the impact of AKT1 mutations on the prognosis remains unclear. We have demonstrated the difference in the clinical significance of the hotspot PIK3CA, AKT1, and ESR1 mutations in cfDNA for each TL in ER+ BC patients.
Liu, Yan; Li, Xiaohong; Johnson, Margaret; Smith, Collette; Kamarulzaman, Adeeba bte; Montaner, Julio; Mounzer, Karam; Saag, Michael; Cahn, Pedro; Cesar, Carina; Krolewiecki, Alejandro; Sanne, Ian; Montaner, Luis J.
2012-01-01
Background Global programs of anti-HIV treatment depend on sustained laboratory capacity to assess treatment initiation thresholds and treatment response over time. Currently, there is no valid alternative to CD4 count testing for monitoring immunologic responses to treatment, but laboratory cost and capacity limit access to CD4 testing in resource-constrained settings. Thus, methods to prioritize patients for CD4 count testing could improve treatment monitoring by optimizing resource allocation. Methods and Findings Using a prospective cohort of HIV-infected patients (n = 1,956) monitored upon antiretroviral therapy initiation in seven clinical sites with distinct geographical and socio-economic settings, we retrospectively apply a novel prediction-based classification (PBC) modeling method. The model uses repeatedly measured biomarkers (white blood cell count and lymphocyte percent) to predict CD4+ T cell outcome through first-stage modeling and subsequent classification based on clinically relevant thresholds (CD4+ T cell count of 200 or 350 cells/µl). The algorithm correctly classified 90% (cross-validation estimate = 91.5%, standard deviation [SD] = 4.5%) of CD4 count measurements <200 cells/µl in the first year of follow-up; if laboratory testing is applied only to patients predicted to be below the 200-cells/µl threshold, we estimate a potential savings of 54.3% (SD = 4.2%) in CD4 testing capacity. A capacity savings of 34% (SD = 3.9%) is predicted using a CD4 threshold of 350 cells/µl. Similar results were obtained over the 3 y of follow-up available (n = 619). Limitations include a need for future economic healthcare outcome analysis, a need for assessment of extensibility beyond the 3-y observation time, and the need to assign a false positive threshold. Conclusions Our results support the use of PBC modeling as a triage point at the laboratory, lessening the need for laboratory-based CD4+ T cell count testing; implementation of this tool could help optimize the use of laboratory resources, directing CD4 testing towards higher-risk patients. However, further prospective studies and economic analyses are needed to demonstrate that the PBC model can be effectively applied in clinical settings. Please see later in the article for the Editors' Summary PMID:22529752
Ab Malik, Normaliza; Mohamad Yatim, Sa'ari; Lam, Otto Lok Tao; Jin, Lijian; McGrath, Colman Patrick Joseph
2017-03-31
Oral hygiene care is of key importance among stroke patients to prevent complications that may compromise rehabilitation or potentially give rise to life-threatening infections such as aspiration pneumonia. The aim of this study was to evaluate the effectiveness of a Web-based continuing professional development (CPD) program on "general intention" of the health carers to perform daily mouth cleaning for stroke patients using the theory of planned behavior (TPB). A double-blind cluster randomized controlled trial was conducted among 547 stroke care providers across 10 hospitals in Malaysia. The centers were block randomized to receive either (1) test intervention (a Web-based CPD program on providing oral hygiene care to stroke patients using TPB) or (2) control intervention (a Web-based CPD program not specific to oral hygiene). Domains of TPB: "attitude," "subjective norm" (SN), "perceived behavior control" (PBC), "general intention" (GI), and "knowledge" related to providing oral hygiene care were assessed preintervention and at 1 month and 6 months postintervention. The overall response rate was 68.2% (373/547). At 1 month, between the test and control groups, there was a significant difference in changes in scores of attitude (P=.004) and subjective norm (P=.01), but not in other TPB domains (GI, P=.11; PBC, P=.51; or knowledge, P=.08). At 6 months, there were significant differences in changes in scores of GI (P=.003), attitude (P=.009), SN (P<.001) and knowledge (P=.001) between the test and control groups. Regression analyses identified that the key factors associated with a change in GI at 6 months were changes in SN (beta=.36, P<.001) and changes in PBC (beta=.23, P<.001). The Web-based CPD program based on TPB increased general intention, attitudes, subjective norms, and knowledge to provide oral hygiene care among stroke carers for their patients. Changing subjective norms and perceived behavioral control are key factors associated with changes in general intention to provide oral hygiene care. National Medical Research Register, Malaysia NMRR-13-1540-18833 (IIR); https://www.nmrr.gov.my/ fwbLoginPage.jsp. ©Normaliza Ab Malik, Sa'ari Mohamad Yatim, Otto Lok Tao Lam, Lijian Jin, Colman Patrick Joseph McGrath. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 31.03.2017.
Díaz-Casares, A; López-González, M V; Peinado-Aragonés, C A; González-Barón, S; Dawid-Milner, M S
2012-08-16
To characterize the possible role of glutamate in the interaction between Hypothalamic Defense Area (HDA) and Parabrachial complex (PBc) nuclei, cardiorespiratory changes were analyzed in response to electrical stimulation of the HDA (1 ms pulses, 30-50 μA given at 100 Hz for 5s) before and after the microinjection of the nonspecific glutamate receptor antagonist kynurenic acid (50 nl, 5 nmol), NMDA receptor antagonist MK-801 (50 nl, 50 nmol), non-NMDA receptor antagonist CNQX (50 nl, 50 nmol) or metabotropic glutamate receptor antagonist MCPG (50 nl, 5 nmol) within the PBc. HDA stimulation evoked an inspiratory facilitatory response, consisting of an increase in respiratory rate (p<0.001) due to a decrease in expiratory time (p<0.01). The respiratory response was accompanied by a pressor (p<0.001) and a tachycardic response (p<0.001). Kynurenic acid within the lateral parabrachial region (lPB) abolished the tachycardia (p<0.001) and decreased the magnitude of blood pressure response (p<0.001) to HDA stimulation. Similarly, the magnitude of the tachycardia and the pressor response was decreased after the microinjection of MK-801 (p<0.01 and p<0.001, respectively) and CNQX (p<0.05 in both cases) into the lPB. Kynurenic acid microinjection in this region produced an inhibition of the tachypnea (p<0.001) to HDA stimulation but the respiratory response persisted unchanged after MK-801 or CNQX microinjection into the lPB. Kynurenic acid within the medial parabrachial region (mPB) abolished the tachycardia (p<0.01) and decreased the magnitude of the pressor response (p<0.001) to HDA stimulation. MK-801 and CNQX microinjection in this region decreased the magnitude of the tachycardia (p<0.05, in both cases) and pressor response (p<0.05, in both cases). The respiratory response evoked by HDA stimulation was not changed after the microinjection of kynurenic acid, MK-801 or CNQX within the mPB. No changes were observed in the cardiorespiratory response evoked to HDA stimulation after MCPG microinjection within lPB and mPB. These results indicate that glutamate PBc receptors are involved in the cardiorespiratory response evoked from the HDA. The possible mechanisms involved in these interactions are discussed. Copyright © 2012 Elsevier B.V. All rights reserved.
High efficiency single transverse mode photonic band crystal lasers with low vertical divergence
NASA Astrophysics Data System (ADS)
Zhao, Shaoyu; Qu, Hongwei; Liu, Yun; Li, Lunhua; Chen, Yang; Zhou, Xuyan; Lin, Yuzhe; Liu, Anjin; Qi, Aiyi; Zheng, Wanhua
2016-10-01
High efficiency 980 nm longitudinal photonic band crystal (PBC) edge emitting laser diodes are designed and fabricated. The calculated results show that eight periods of Al0.1Ga0.9As and Al0.25Ga0.75As layer pairs can reduce the vertical far field divergence to 10.6° full width at half maximum (FWHM). The broad area (BA) lasers show a very high internal quantum efficiency ηi of 98% and low internal loss αi of 1.92 cm-1. Ridge waveguide (RW) lasers with 3 mm cavity length and 5um strip width provide 430 mW stable single transverse mode output at 500 mA injection current with power conversion efficiency (PCE) of 47% under continuous wave (CW) mode. A maximum PCE of 50% is obtained at the 300 mA injection current. A very low vertical far field divergence of 9.4° is obtained at 100 mA injection. At 500 mA injection, the vertical far field divergence increases to 11°, the beam quality factors M2 values are 1.707 in vertical direction and 1.769 in lateral direction.
Robinson, Natalie G; Masser, Barbara M; White, Katherine M; Hyde, Melissa K; Terry, Deborah J
2008-12-01
With an increasing demand for blood and blood products in Australia, there is a continual need to recruit blood donors. As such, it is important to investigate the factors that impact on nondonors' decision-making processes with regard to donating blood for the first time. Previous research has established the efficacy of the theory of planned behavior (TPB) in predicting blood donor intentions. The current research aimed to test a TPB model augmented with constructs implicated in previous blood donor research; specifically descriptive norm, moral norm, anticipated regret, and donation anxiety. Participants completed measures assessing the standard TPB variables of attitude, subjective norm, and perceived behavioral control (PBC) as well as descriptive norm, moral norm, donation anxiety, and anticipated regret. Path analysis examined the utility of the augmented TPB model to predict 195 non-blood donors' intentions to donate blood. A final revised model provided a very good fit to the data and included attitude, PBC, moral norm, descriptive norm, anticipated regret, and donation anxiety as direct predictors of intention, with these factors accounting for 70 percent of the variance in intentions to donate blood. A revised TPB model provided a more efficacious predictor of nondonors' intentions to donate than the standard TPB model and highlights the role that norm-based factors and affective-laden constructs play in predicting non-blood donors' intentions to donate.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shen, Yanwen; Linville, Jessica L.; Ignacio-de Leon, Patricia Anne A.
This study presents an integrated waste-to-energy process, using two waste streams, sludge generated from the municipal wastewater treatment plants (WWTPs) and biochar generated from the biomass gasification systems, to produce fungible biomethane and nutrient-rich digestate with fertilizer value. Two woody biochar, namely pinewood (PBC) and white oak biochar (WOBC) were used as additives during anaerobic digestion (AD) of WWTP sludge to enhance methane production at mesophilic and thermophilic temperatures. The PBC and WOBC have porous structure, large surface area and desirable chemical properties to be used as AD amendment material to sequester CO2 from biogas in the digester. The biochar-amendedmore » digesters achieved average methane content in biogas of up to 92.3% and 79.0%, corresponding to CO2 sequestration by up to 66.2% and 32.4% during mesophilic and thermophilic AD, respectively. Biochar addition enhanced process stability by increasing the alkalinity, but inhibitory effects were observed at high dosage. It also alleviated free ammonia inhibition by up to 10.5%. The biochar-amended digesters generated digestate rich in macro- and micronutrients including K (up to 300 m/L), Ca (up to 750 mg/L), Mg (up to 1800 mg/L) and Fe (up to 390 mg/L), making biochar-amended digestate a potential alternative used as agricultural lime fertilizer.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Maselli, A.; Cusumano, G.; La Parola, V.
We searched for {gamma}-ray blazar candidates among the 382 unidentified hard X-ray sources of the third Palermo BAT Catalog (3PBC) obtained from the analysis of 66 months of Swift Burst Alert Telescope (BAT) survey data and listing 1586 sources. We adopted a recently developed association method based on the peculiar infrared colors that characterize the {gamma}-ray blazars included in the second catalog of active galactic nuclei detected by the Fermi Large Area Telescope. We used this method exploiting the data of the all-sky survey performed by the Wide-field Infrared Survey Explorer (WISE) to establish correspondences between unidentified 3PBC sources andmore » WISE {gamma}-ray blazar candidates located within the BAT positional uncertainty region at a 99% confidence level. We obtained a preliminary list of candidates for which we analyzed all the available data in the Swift archive to complement the information in the literature and in the radio, infrared, and optical catalogs with the information on their optical-UV and soft X-ray emission. Requiring the presence of radio and soft X-ray counterparts consistent with the infrared positions of the selected WISE sources, as well as a blazar-like radio morphology, we finally obtained a list of 24 {gamma}-ray blazar candidates.« less
Carvalho, Rimenys J; Woo, James; Aires-Barros, M Raquel; Cramer, Steven M; Azevedo, Ana M
2014-10-01
Phenylboronate chromatography (PBC) has been applied for several years, however details regarding the mechanisms of interactions between the ligand and biomolecules are still scarce. The goal of this work is to investigate the various chemical interactions between proteins and their ligands, using a protein library containing both glycosylated and nonglycosylated proteins. Differences in the adsorption of these proteins over a pH range from 4 to 9 were related to two main properties: charge and presence of glycans. Acidic or neutral proteins were strongly adsorbed below pH 8 although the uncharged trigonal form of phenylboronate (PB) is less susceptible to forming electrostatic and cis-diol interactions with proteins. The glycosylated proteins were only adsorbed above pH 8 when the electrostatic repulsion between the boronate anion and the protein surface was mitigated (at 200 mM NaCl). All basic proteins were highly adsorbed above pH 8 with PB also acting as a cation-exchanger with binding occurring through electrostatic interactions. Batch adsorption performed at acidic conditions in the presence of Lewis base showed that charge-transfer interactions are critical for protein retention. This study demonstrates the multimodal interaction of PBC, which can be a selective tool for separation of different classes of proteins. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Banas, Kasia; Lyimo, Ramsey A; Hospers, Harm J; van der Ven, Andre; de Bruin, Marijn
2017-10-01
Combination antiretroviral therapy (cART) for HIV is widely available in sub-Saharan Africa. Adherence is crucial to successful treatment. This study aimed to apply an extended theory of planned behaviour (TPB) model to predict objectively measured adherence to cART in Tanzania. Prospective observational study (n = 158) where patients completed questionnaires on demographics (Month 0), socio-cognitive variables including intentions (Month 1), and action planning and self-regulatory processes hypothesised to mediate the intention-behaviour relationship (Month 3), to predict adherence (Month 5). Taking adherence was measured objectively using the Medication Events Monitoring System (MEMS) caps. Model tests were conducted using regression and bootstrap mediation analyses. Perceived behavioural control (PBC) was positively (β = .767, p < .001, R 2 = 57.5%) associated with adherence intentions. Intentions only exercised an indirect effect on adherence (B = 1.29 [0.297-3.15]) through self-regulatory processes (B = 1.10 [0.131-2.87]). Self-regulatory processes (β = .234, p = .010, R 2 = 14.7%) predicted better adherence. This observational study using an objective behavioural measure, identified PBC as the main driver of adherence intentions. The effect of intentions on adherence was only indirect through self-regulatory processes, which were the main predictor of objectively assessed adherence.
Starfelt Sutton, Louise C; White, Katherine M
2016-11-01
To synthesise theory of planned behaviour (TPB) relationships, using meta-analysis, and test the predictive utility of the model for sun protection behaviour. Thirty-eight samples were identified via database/manual searches and academic society posts based on the criteria: measuring sun-protective intentions and/or prospective behaviour; using the TPB/theory of reasoned action as a basis of measurement; and providing bivariate correlations for at least one relevant TPB association. Sun-protective intentions and behaviours. The sample-weighted average effects were moderate-to-strong with attitudes showing the strongest association with intention (r+ = 0.494), followed by perceived behavioural control (PBC; r+ = 0.451), and subjective norm (r+ = 0.419). Intentions showed a stronger association with prospective behaviour (r+ = 0.486) compared to PBC (r+ = 0.314). A total of 39% of variance in intentions and 25% of variance in behaviour were explained. Publication bias was not evident. Moderator analyses showed that TPB associations were stronger when measures specified the Target, Action, Context and Time; in non-student samples; and when follow-up exceeded two weeks. Despite recent criticism, this review shows that the TPB explains a large amount of variance in sun protection and that TPB associations are robust across different populations.
Shen, Yanwen; Forrester, Sara; Koval, Jason; ...
2017-05-29
This study aimed to scale up an integrated waste-to-energy system for producing pipelinequality biomethane from shake flasks experiments to two-stage digester systems with semicontinuous operation. The yearlong operation was successfully conducted to compare the performance of thermophilic anaerobic digestion (AD) of sewage sludge amended with corn stover biochar (CSBC) and pine biochar (PBC) to the control under various conditions. Both CSBC and PBC promoted the substrate utilization, methane productivity, and process stability of AD, while CSBC showed superior potential. CSBC enhanced methane content in biogas (CH 4%) and methane production rate (P CHmore » $$_4$$) by up to 25% and 37% respectively in comparison to the control, with maximum CH 4% of 95% and CH 4 yield of 0.34 L/g volatile solid (VS)-added being achieved at steady state. The biochar supplementation also led to a substantial increase of the macro- and micro-nutrients (P, K, Ca, Mg, Fe) by up to 33 times in the digestate, increasing its fertilizer value. Finally, microbial community structure and dynamics were also investigated and compared, and in particular, CSBC promoted the abundance of Clostridia and Methanosarcina. Collectively, this study proves that pyro-biochar as an effective additive material enhances AD performance with continuous operation and that CSBC shows greater potential.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shen, Yanwen; Forrester, Sara; Koval, Jason
This study aimed to scale up an integrated waste-to-energy system for producing pipelinequality biomethane from shake flasks experiments to two-stage digester systems with semicontinuous operation. The yearlong operation was successfully conducted to compare the performance of thermophilic anaerobic digestion (AD) of sewage sludge amended with corn stover biochar (CSBC) and pine biochar (PBC) to the control under various conditions. Both CSBC and PBC promoted the substrate utilization, methane productivity, and process stability of AD, while CSBC showed superior potential. CSBC enhanced methane content in biogas (CH 4%) and methane production rate (P CHmore » $$_4$$) by up to 25% and 37% respectively in comparison to the control, with maximum CH 4% of 95% and CH 4 yield of 0.34 L/g volatile solid (VS)-added being achieved at steady state. The biochar supplementation also led to a substantial increase of the macro- and micro-nutrients (P, K, Ca, Mg, Fe) by up to 33 times in the digestate, increasing its fertilizer value. Finally, microbial community structure and dynamics were also investigated and compared, and in particular, CSBC promoted the abundance of Clostridia and Methanosarcina. Collectively, this study proves that pyro-biochar as an effective additive material enhances AD performance with continuous operation and that CSBC shows greater potential.« less
Calculating Time-Integral Quantities in Depletion Calculations
Isotalo, Aarno
2016-06-02
A method referred to as tally nuclides is presented for accurately and efficiently calculating the time-step averages and integrals of any quantities that are weighted sums of atomic densities with constant weights during the step. The method allows all such quantities to be calculated simultaneously as a part of a single depletion solution with existing depletion algorithms. Some examples of the results that can be extracted include step-average atomic densities and macroscopic reaction rates, the total number of fissions during the step, and the amount of energy released during the step. Furthermore, the method should be applicable with several depletionmore » algorithms, and the integrals or averages should be calculated with an accuracy comparable to that reached by the selected algorithm for end-of-step atomic densities. The accuracy of the method is demonstrated in depletion calculations using the Chebyshev rational approximation method. Here, we demonstrate how the ability to calculate energy release in depletion calculations can be used to determine the accuracy of the normalization in a constant-power burnup calculation during the calculation without a need for a reference solution.« less
Influence of metallic dental implants and metal artefacts on dose calculation accuracy.
Maerz, Manuel; Koelbl, Oliver; Dobler, Barbara
2015-03-01
Metallic dental implants cause severe streaking artefacts in computed tomography (CT) data, which inhibit the correct representation of shape and density of the metal and the surrounding tissue. The aim of this study was to investigate the impact of dental implants on the accuracy of dose calculations in radiation therapy planning and the benefit of metal artefact reduction (MAR). A second aim was to determine the treatment technique which is less sensitive to the presence of metallic implants in terms of dose calculation accuracy. Phantoms consisting of homogeneous water equivalent material surrounding dental implants were designed. Artefact-containing CT data were corrected using the correct density information. Intensity-modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT) plans were calculated on corrected and uncorrected CT data and compared to 2-dimensional dose measurements using GafChromic™ EBT2 films. For all plans the accuracy of dose calculations is significantly higher if performed on corrected CT data (p = 0.015). The agreement of calculated and measured dose distributions is significantly higher for VMAT than for IMRT plans for calculations on uncorrected CT data (p = 0.011) as well as on corrected CT data (p = 0.029). For IMRT and VMAT the application of metal artefact reduction significantly increases the agreement of dose calculations with film measurements. VMAT was found to provide the highest accuracy on corrected as well as on uncorrected CT data. VMAT is therefore preferable over IMRT for patients with metallic implants, if plan quality is comparable for the two techniques.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Hsiang-Hsu; Taam, Ronald E.; Yen, David C. C., E-mail: yen@math.fju.edu.tw
Investigating the evolution of disk galaxies and the dynamics of proto-stellar disks can involve the use of both a hydrodynamical and a Poisson solver. These systems are usually approximated as infinitesimally thin disks using two-dimensional Cartesian or polar coordinates. In Cartesian coordinates, the calculations of the hydrodynamics and self-gravitational forces are relatively straightforward for attaining second-order accuracy. However, in polar coordinates, a second-order calculation of self-gravitational forces is required for matching the second-order accuracy of hydrodynamical schemes. We present a direct algorithm for calculating self-gravitational forces with second-order accuracy without artificial boundary conditions. The Poisson integral in polar coordinates ismore » expressed in a convolution form and the corresponding numerical complexity is nearly linear using a fast Fourier transform. Examples with analytic solutions are used to verify that the truncated error of this algorithm is of second order. The kernel integral around the singularity is applied to modify the particle method. The use of a softening length is avoided and the accuracy of the particle method is significantly improved.« less
NASA Technical Reports Server (NTRS)
Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.
1989-01-01
Recent advances in electronic structure theory and the availability of high speed vector processors have substantially increased the accuracy of ab initio potential energy surfaces. The recently developed atomic natural orbital approach for basis set contraction has reduced both the basis set incompleteness and superposition errors in molecular calculations. Furthermore, full CI calculations can often be used to calibrate a CASSCF/MRCI approach that quantitatively accounts for the valence correlation energy. These computational advances also provide a vehicle for systematically improving the calculations and for estimating the residual error in the calculations. Calculations on selected diatomic and triatomic systems will be used to illustrate the accuracy that currently can be achieved for molecular systems. In particular, the F + H2 yields HF + H potential energy hypersurface is used to illustrate the impact of these computational advances on the calculation of potential energy surfaces.
NASA Technical Reports Server (NTRS)
Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.
1988-01-01
Recent advances in electronic structure theory and the availability of high speed vector processors have substantially increased the accuracy of ab initio potential energy surfaces. The recently developed atomic natural orbital approach for basis set contraction has reduced both the basis set incompleteness and superposition errors in molecular calculations. Furthermore, full CI calculations can often be used to calibrate a CASSCF/MRCI approach that quantitatively accounts for the valence correlation energy. These computational advances also provide a vehicle for systematically improving the calculations and for estimating the residual error in the calculations. Calculations on selected diatomic and triatomic systems will be used to illustrate the accuracy that currently can be achieved for molecular systems. In particular, the F+H2 yields HF+H potential energy hypersurface is used to illustrate the impact of these computational advances on the calculation of potential energy surfaces.
Jung, Hyung-Sup; Lee, Won-Jin; Zhang, Lei
2014-01-01
The measurement of precise along-track displacements has been made with the multiple-aperture interferometry (MAI). The empirical accuracies of the MAI measurements are about 6.3 and 3.57 cm for ERS and ALOS data, respectively. However, the estimated empirical accuracies cannot be generalized to any interferometric pair because they largely depend on the processing parameters and coherence of the used SAR data. A theoretical formula is given to calculate an expected MAI measurement accuracy according to the system and processing parameters and interferometric coherence. In this paper, we have investigated the expected MAI measurement accuracy on the basis of the theoretical formula for the existing X-, C- and L-band satellite SAR systems. The similarity between the expected and empirical MAI measurement accuracies has been tested as well. The expected accuracies of about 2–3 cm and 3–4 cm (γ = 0.8) are calculated for the X- and L-band SAR systems, respectively. For the C-band systems, the expected accuracy of Radarsat-2 ultra-fine is about 3–4 cm and that of Sentinel-1 IW is about 27 cm (γ = 0.8). The results indicate that the expected MAI measurement accuracy of a given interferometric pair can be easily calculated by using the theoretical formula. PMID:25251408
On a fast calculation of structure factors at a subatomic resolution.
Afonine, P V; Urzhumtsev, A
2004-01-01
In the last decade, the progress of protein crystallography allowed several protein structures to be solved at a resolution higher than 0.9 A. Such studies provide researchers with important new information reflecting very fine structural details. The signal from these details is very weak with respect to that corresponding to the whole structure. Its analysis requires high-quality data, which previously were available only for crystals of small molecules, and a high accuracy of calculations. The calculation of structure factors using direct formulae, traditional for 'small-molecule' crystallography, allows a relatively simple accuracy control. For macromolecular crystals, diffraction data sets at a subatomic resolution contain hundreds of thousands of reflections, and the number of parameters used to describe the corresponding models may reach the same order. Therefore, the direct way of calculating structure factors becomes very time expensive when applied to large molecules. These problems of high accuracy and computational efficiency require a re-examination of computer tools and algorithms. The calculation of model structure factors through an intermediate generation of an electron density [Sayre (1951). Acta Cryst. 4, 362-367; Ten Eyck (1977). Acta Cryst. A33, 486-492] may be much more computationally efficient, but contains some parameters (grid step, 'effective' atom radii etc.) whose influence on the accuracy of the calculation is not straightforward. At the same time, the choice of parameters within safety margins that largely ensure a sufficient accuracy may result in a significant loss of the CPU time, making it close to the time for the direct-formulae calculations. The impact of the different parameters on the computer efficiency of structure-factor calculation is studied. It is shown that an appropriate choice of these parameters allows the structure factors to be obtained with a high accuracy and in a significantly shorter time than that required when using the direct formulae. Practical algorithms for the optimal choice of the parameters are suggested.
Horibe, Takuro; Ishii, Katsunori; Fukutomi, Daichi; Awazu, Kunio
2015-12-30
An estimation error of the scattering coefficient of hemoglobin in the high absorption wavelength range has been observed in optical property calculations of blood-rich tissues. In this study, the relationship between the accuracy of diffuse reflectance measurement in the integrating sphere and calculated scattering coefficient was evaluated with a system to calculate optical properties combined with an integrating sphere setup and the inverse Monte Carlo simulation. Diffuse reflectance was measured with the integrating sphere using a small incident port diameter and optical properties were calculated. As a result, the estimation error of the scattering coefficient was improved by accurate measurement of diffuse reflectance. In the high absorption wavelength range, the accuracy of diffuse reflectance measurement has an effect on the calculated scattering coefficient.
1987-07-01
nontransformable Bacillus species such as B. anthracis. Our results suggest that plasmid pLS20 of Bacillus subtilis ( natto ), which promotes transfer of the...mobilizing pBC16, pLS20 mediates transfer of the B. subtills ( natto ) plasmid pLS19 and the Staphylococcus aureus plasmid pUB110. To facilitate direct...and (v) transformation of B. cereus and B. anthracis with plasmid DNA. The 55-kb plasmid, pLS20, of Bacillus subtilis ( natto ) 3335 promotes tr msfer
Piezoelectric and Electrostrictive Materials for Transducer Applications. Volume 3.
1988-03-01
the preparation and characterization of these required compositions. High-purity lead acetate, titanium isopropoxide , and zirconium n-propoxide were...method was similar to the procedure used in Reference 4 to prepare PbTiO 3. High-purity lead acetate [Pb(C2 H3 0 2 )2 -3H-2Oj, titanium isopropoxide [Ti(OC...dielectric constant as shown in Figure 14(A). P. 8 IV. CONCLUSION High-purity lead acetate, titanium isopropoxide and zirconium n-propoxide were used as
Chen, Li-Feng; Huang, Zhi-Hong; Liang, Hai-Wei; Guan, Qing-Fang; Yu, Shu-Hong
2013-09-14
A new kind of high-performance asymmetric supercapacitor is designed with pyrolyzed bacterial cellulose (p-BC)-coated MnO₂ as a positive electrode material and nitrogen-doped p-BC as a negative electrode material via an easy, efficient, large-scale, and green fabrication approach. The optimal asymmetric device possesses an excellent supercapacitive behavior with quite high energy and power density. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
NASA Technical Reports Server (NTRS)
Hughes, D. L.; Ray, R. J.; Walton, J. T.
1985-01-01
The calculated value of net thrust of an aircraft powered by a General Electric F404-GE-400 afterburning turbofan engine was evaluated for its sensitivity to various input parameters. The effects of a 1.0-percent change in each input parameter on the calculated value of net thrust with two calculation methods are compared. This paper presents the results of these comparisons and also gives the estimated accuracy of the overall net thrust calculation as determined from the influence coefficients and estimated parameter measurement accuracies.
Boucher, M.S.
1994-01-01
Water-level measurements have been made in deep boreholes in the Yucca Mountain area, Nye County, Nevada, since 1983 in support of the U.S. Department of Energy's Yucca Mountain Project, which is an evaluation of the area to determine its suitability as a potential storage area for high-level nuclear waste. Water-level measurements were taken either manually, using various water-level measuring equipment such as steel tapes, or they were taken continuously, using automated data recorders and pressure transducers. This report presents precision range and accuracy data established for manual water-level measurements taken in the Yucca Mountain area, 1988-90. Precision and accuracy ranges were determined for all phases of the water-level measuring process, and overall accuracy ranges are presented. Precision ranges were determined for three steel tapes using a total of 462 data points. Mean precision ranges of these three tapes ranged from 0.014 foot to 0.026 foot. A mean precision range of 0.093 foot was calculated for the multiconductor cable, using 72 data points. Mean accuracy values were calculated on the basis of calibrations of the steel tapes and the multiconductor cable against a reference steel tape. The mean accuracy values of the steel tapes ranged from 0.053 foot, based on three data points to 0.078, foot based on six data points. The mean accuracy of the multiconductor cable was O. 15 foot, based on six data points. Overall accuracy of the water-level measurements was calculated by taking the square root of the sum of the squares of the individual accuracy values. Overall accuracy was calculated to be 0.36 foot for water-level measurements taken with steel tapes, without accounting for the inaccuracy of borehole deviations from vertical. An overall accuracy of 0.36 foot for measurements made with steel tapes is considered satisfactory for this project.
Bistoni, Giovanni; Riplinger, Christoph; Minenkov, Yury; Cavallo, Luigi; Auer, Alexander A; Neese, Frank
2017-07-11
The validity of the main approximations used in canonical and domain based pair natural orbital coupled cluster methods (CCSD(T) and DLPNO-CCSD(T), respectively) in standard chemical applications is discussed. In particular, we investigate the dependence of the results on the number of electrons included in the correlation treatment in frozen-core (FC) calculations and on the main threshold governing the accuracy of DLPNO all-electron (AE) calculations. Initially, scalar relativistic orbital energies for the ground state of the atoms from Li to Rn in the periodic table are calculated. An energy criterion is used for determining the orbitals that can be excluded from the correlation treatment in FC coupled cluster calculations without significant loss of accuracy. The heterolytic dissociation energy (HDE) of a series of metal compounds (LiF, NaF, AlF 3 , CaF 2 , CuF, GaF 3 , YF 3 , AgF, InF 3 , HfF 4 , and AuF) is calculated at the canonical CCSD(T) level, and the dependence of the results on the number of correlated electrons is investigated. Although for many of the studied reactions subvalence correlation effects contribute significantly to the HDE, the use of an energy criterion permits a conservative definition of the size of the core, allowing FC calculations to be performed in a black-box fashion while retaining chemical accuracy. A comparison of the CCSD and the DLPNO-CCSD methods in describing the core-core, core-valence, and valence-valence components of the correlation energy is given. It is found that more conservative thresholds must be used for electron pairs containing at least one core electron in order to achieve high accuracy in AE DLPNO-CCSD calculations relative to FC calculations. With the new settings, the DLPNO-CCSD method reproduces canonical CCSD results in both AE and FC calculations with the same accuracy.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Isotalo, Aarno
A method referred to as tally nuclides is presented for accurately and efficiently calculating the time-step averages and integrals of any quantities that are weighted sums of atomic densities with constant weights during the step. The method allows all such quantities to be calculated simultaneously as a part of a single depletion solution with existing depletion algorithms. Some examples of the results that can be extracted include step-average atomic densities and macroscopic reaction rates, the total number of fissions during the step, and the amount of energy released during the step. Furthermore, the method should be applicable with several depletionmore » algorithms, and the integrals or averages should be calculated with an accuracy comparable to that reached by the selected algorithm for end-of-step atomic densities. The accuracy of the method is demonstrated in depletion calculations using the Chebyshev rational approximation method. Here, we demonstrate how the ability to calculate energy release in depletion calculations can be used to determine the accuracy of the normalization in a constant-power burnup calculation during the calculation without a need for a reference solution.« less
Evaluation and attribution of OCO-2 XCO2 uncertainties
NASA Astrophysics Data System (ADS)
Worden, John R.; Doran, Gary; Kulawik, Susan; Eldering, Annmarie; Crisp, David; Frankenberg, Christian; O'Dell, Chris; Bowman, Kevin
2017-07-01
Evaluating and attributing uncertainties in total column atmospheric CO2 measurements (XCO2) from the OCO-2 instrument is critical for testing hypotheses related to the underlying processes controlling XCO2 and for developing quality flags needed to choose those measurements that are usable for carbon cycle science.Here we test the reported uncertainties of version 7 OCO-2 XCO2 measurements by examining variations of the XCO2 measurements and their calculated uncertainties within small regions (˜ 100 km × 10.5 km) in which natural CO2 variability is expected to be small relative to variations imparted by noise or interferences. Over 39 000 of these small neighborhoods
comprised of approximately 190 observations per neighborhood are used for this analysis. We find that a typical ocean measurement has a precision and accuracy of 0.35 and 0.24 ppm respectively for calculated precisions larger than ˜ 0.25 ppm. These values are approximately consistent with the calculated errors of 0.33 and 0.14 ppm for the noise and interference error, assuming that the accuracy is bounded by the calculated interference error. The actual precision for ocean data becomes worse as the signal-to-noise increases or the calculated precision decreases below 0.25 ppm for reasons that are not well understood. A typical land measurement, both nadir and glint, is found to have a precision and accuracy of approximately 0.75 and 0.65 ppm respectively as compared to the calculated precision and accuracy of approximately 0.36 and 0.2 ppm. The differences in accuracy between ocean and land suggests that the accuracy of XCO2 data is likely related to interferences such as aerosols or surface albedo as they vary less over ocean than land. The accuracy as derived here is also likely a lower bound as it does not account for possible systematic biases between the regions used in this analysis.
Accuracy Improvement in Magnetic Field Modeling for an Axisymmetric Electromagnet
NASA Technical Reports Server (NTRS)
Ilin, Andrew V.; Chang-Diaz, Franklin R.; Gurieva, Yana L.; Il,in, Valery P.
2000-01-01
This paper examines the accuracy and calculation speed for the magnetic field computation in an axisymmetric electromagnet. Different numerical techniques, based on an adaptive nonuniform grid, high order finite difference approximations, and semi-analitical calculation of boundary conditions are considered. These techniques are being applied to the modeling of the Variable Specific Impulse Magnetoplasma Rocket. For high-accuracy calculations, a fourth-order scheme offers dramatic advantages over a second order scheme. For complex physical configurations of interest in plasma propulsion, a second-order scheme with nonuniform mesh gives the best results. Also, the relative advantages of various methods are described when the speed of computation is an important consideration.
NASA Astrophysics Data System (ADS)
Perera, Dimuthu
Diffusion weighted (DW) Imaging is a non-invasive MR technique that provides information about the tissue microstructure using the diffusion of water molecules. The diffusion is generally characterized by the apparent diffusion coefficient (ADC) parametric map. The purpose of this study is to investigate in silico how the calculation of ADC is affected by image SNR, b-values, and the true tissue ADC. Also, to provide optimal parameter combination depending on the percentage accuracy and precision for prostate peripheral region cancer application. Moreover, to suggest parameter choices for any type of tissue, while providing the expected accuracy and precision. In this research DW images were generated assuming a mono-exponential signal model at two different b-values and for known true ADC values. Rician noise of different levels was added to the DWI images to adjust the image SNR. Using the two DWI images, ADC was calculated using a mono-exponential model for each set of b-values, SNR, and true ADC. 40,000 ADC data were collected for each parameter setting to determine the mean and the standard-deviation of the calculated ADC, as well as the percentage accuracy and precision with respect to the true ADC. The accuracy was calculated using the difference between known and calculated ADC. The precision was calculated using the standard-deviation of calculated ADC. The optimal parameters for a specific study was determined when both the percentage accuracy and precision were minimized. In our study, we simulated two true ADCs (ADC 0.00102 for tumor and 0.00180 mm2/s for normal prostate peripheral region tissue). Image SNR was varied from 2 to 100 and b-values were varied from 0 to 2000s/mm2. The results show that the percentage accuracy and percentage precision were minimized with image SNR. To increase SNR, 10 signal-averagings (NEX) were used considering the limitation in total scan time. The optimal NEX combination for tumor and normal tissue for prostate peripheral region was 1: 9. Also, the minimum percentage accuracy and percentage precision were obtained when low b-value is 0 and high b-value is 800 mm2/s for normal tissue and 1400 mm2/s for tumor tissue. Results also showed that for tissues with 1 x 10-3 < ADC < 2.1 x 10-3 mm 2/s the parameter combination at SNR = 20, b-value pair 0, 800 mm 2/s with NEX = 1:9 can calculate ADC with a percentage accuracy of less than 2% and percentage precision of 6-8%. Also, for tissues with 0.6 x 10-3 < ADC < 1.25 x 10-3 mm2 /s the parameter combination at SNR = 20, b-value pair 0, 1400 mm 2/s with NEX =1:9 can calculate ADC with a percentage accuracy of less than 2% and percentage precision of 6-8%.
Increase in the Accuracy of Calculating Length of Horizontal Cable SCS in Civil Engineering
NASA Astrophysics Data System (ADS)
Semenov, A.
2017-11-01
A modification of the method for calculating the horizontal cable consumption of SCS established at civil engineering facilities is proposed. The proposed procedure preserves the prototype simplicity and provides a 5 percent accuracy increase. The values of the achieved accuracy are justified, their compliance with the practice of real projects is proved. The method is brought to the level of the engineering algorithm and formalized in the form of 12/70 rule.
NASA Astrophysics Data System (ADS)
Khoshkholgh, Mehri Javan; Marsusi, Farah; Abolhassani, Mohammad Reza
2015-02-01
PTBs polymers with thieno[3,4-b]thiophene [TT] and benzodithiophene [BDT] units have particular properties, which demonstrate it as one of the best group of donor materials in organic solar cells. In the present work, density functional theory (DFT) is applied to investigate the optimized structure, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO), band gap and dihedral angle of PTB7 at B3LYP/6-31G(d). Two different approaches are applied to carry out these investigations: Oligomer extrapolation technique and periodic boundary condition (PBC) method. The results obtained from PBC-DFT method are in fair agreement with experiments. Based on these reliable outcomes; the investigations continued to perform some derivatives of PTB7. In this study, sulfur is substituted by nitrogen, oxygen, silicon, phosphor or selenium atoms in pristine PTB7. Due to the shift of HOMO and LUMO levels, smaller band gaps are predicted to appear in some derivatives in comparison with PTB7. Maximum theoretical efficiencies, η, of the mentioned derivatives as well as local difference of dipole moments between the ground and excited states (Δμge) are computed. The results indicate that substitution of sulfur by nitrogen or oxygen in BDT unit, and silicon or phosphor in TT unit of pristine PTB7 leads to a higher η as well as Δμge.
Wang, Jia; Liu, Ru-De; Ding, Yi; Liu, Ying; Xu, Le; Zhen, Rui
2017-01-01
This study investigated how and why Chinese adolescents choose between playing online games and doing homework, using the model of the theory of planned behavior (TPB) in which the subjective norm was manipulated as two sub-elements (peer support and parental monitoring). A total of 530 students from an elementary school and a middle school in China were asked to complete the measures assessing two predictors of TPB: attitude and perceived behavioral control (PBC). Next, they completed a survey about their choice intention between playing an online game and doing homework in three different situations, wherein a conflict between playing online games and doing homework was introduced and subjective norm was manipulated as peers supporting and parents objecting to playing online games. The results showed that adolescents’ attitude and PBC, as well as the perception of obtaining or not obtaining support from their peers and caregivers (manipulated subjective norm), significantly influenced their choice intention in online gaming situations. These findings contribute to the understanding of the factors affecting adolescents’ online gaming, which has been a concern of both caregivers and educators. With regard to the theoretical implications, this study extended previous work by providing evidence that TPB can be applied to analyze choice intention. Moreover, this study illuminated the effects of the separating factors of subjective norm on choice intention between playing online games and studying. PMID:28458649
Lagardère, Louis; Lipparini, Filippo; Polack, Étienne; Stamm, Benjamin; Cancès, Éric; Schnieders, Michael; Ren, Pengyu; Maday, Yvon; Piquemal, Jean-Philip
2014-02-28
In this paper, we present a scalable and efficient implementation of point dipole-based polarizable force fields for molecular dynamics (MD) simulations with periodic boundary conditions (PBC). The Smooth Particle-Mesh Ewald technique is combined with two optimal iterative strategies, namely, a preconditioned conjugate gradient solver and a Jacobi solver in conjunction with the Direct Inversion in the Iterative Subspace for convergence acceleration, to solve the polarization equations. We show that both solvers exhibit very good parallel performances and overall very competitive timings in an energy-force computation needed to perform a MD step. Various tests on large systems are provided in the context of the polarizable AMOEBA force field as implemented in the newly developed Tinker-HP package which is the first implementation for a polarizable model making large scale experiments for massively parallel PBC point dipole models possible. We show that using a large number of cores offers a significant acceleration of the overall process involving the iterative methods within the context of spme and a noticeable improvement of the memory management giving access to very large systems (hundreds of thousands of atoms) as the algorithm naturally distributes the data on different cores. Coupled with advanced MD techniques, gains ranging from 2 to 3 orders of magnitude in time are now possible compared to non-optimized, sequential implementations giving new directions for polarizable molecular dynamics in periodic boundary conditions using massively parallel implementations.
Lagardère, Louis; Lipparini, Filippo; Polack, Étienne; Stamm, Benjamin; Cancès, Éric; Schnieders, Michael; Ren, Pengyu; Maday, Yvon; Piquemal, Jean-Philip
2015-01-01
In this paper, we present a scalable and efficient implementation of point dipole-based polarizable force fields for molecular dynamics (MD) simulations with periodic boundary conditions (PBC). The Smooth Particle-Mesh Ewald technique is combined with two optimal iterative strategies, namely, a preconditioned conjugate gradient solver and a Jacobi solver in conjunction with the Direct Inversion in the Iterative Subspace for convergence acceleration, to solve the polarization equations. We show that both solvers exhibit very good parallel performances and overall very competitive timings in an energy-force computation needed to perform a MD step. Various tests on large systems are provided in the context of the polarizable AMOEBA force field as implemented in the newly developed Tinker-HP package which is the first implementation for a polarizable model making large scale experiments for massively parallel PBC point dipole models possible. We show that using a large number of cores offers a significant acceleration of the overall process involving the iterative methods within the context of spme and a noticeable improvement of the memory management giving access to very large systems (hundreds of thousands of atoms) as the algorithm naturally distributes the data on different cores. Coupled with advanced MD techniques, gains ranging from 2 to 3 orders of magnitude in time are now possible compared to non-optimized, sequential implementations giving new directions for polarizable molecular dynamics in periodic boundary conditions using massively parallel implementations. PMID:26512230
Komaroff, Marina
2016-01-01
The aim of this study is to investigate if weight fluctuation is an independent risk factor for postmenopausal breast cancer (PBC) among women who gained weight in adult years. NHANES I Epidemiologic Follow-Up Study (NHEFS) database was used in the study. Women that were cancers-free at enrollment and diagnosed for the first time with breast cancer at age 50 or greater were considered cases. Controls were chosen from the subset of cancers-free women and matched to cases by years of follow-up and status of body mass index (BMI) at 25 years of age. Weight fluctuation was measured by the root-mean-square-error (RMSE) from a simple linear regression model for each woman with their body mass index (BMI) regressed on age (started at 25 years) while women with the positive slope from this regression were defined as weight gainers. Data were analyzed using conditional logistic regression models. A total of 158 women were included into the study. The conditional logistic regression adjusted for weight gain demonstrated positive association between weight fluctuation in adult years and postmenopausal breast cancers (odds ratio/OR = 1.67; 95% confidence interval/CI: 1.06-2.66). The data suggested that long-term weight fluctuation was significant risk factor for PBC among women who gained weight in adult years. This finding underscores the importance of maintaining lost weight and avoiding weight fluctuation.
Komaroff, Marina
2016-01-01
Objective. The aim of this study is to investigate if weight fluctuation is an independent risk factor for postmenopausal breast cancer (PBC) among women who gained weight in adult years. Methods. NHANES I Epidemiologic Follow-Up Study (NHEFS) database was used in the study. Women that were cancers-free at enrollment and diagnosed for the first time with breast cancer at age 50 or greater were considered cases. Controls were chosen from the subset of cancers-free women and matched to cases by years of follow-up and status of body mass index (BMI) at 25 years of age. Weight fluctuation was measured by the root-mean-square-error (RMSE) from a simple linear regression model for each woman with their body mass index (BMI) regressed on age (started at 25 years) while women with the positive slope from this regression were defined as weight gainers. Data were analyzed using conditional logistic regression models. Results. A total of 158 women were included into the study. The conditional logistic regression adjusted for weight gain demonstrated positive association between weight fluctuation in adult years and postmenopausal breast cancers (odds ratio/OR = 1.67; 95% confidence interval/CI: 1.06–2.66). Conclusions. The data suggested that long-term weight fluctuation was significant risk factor for PBC among women who gained weight in adult years. This finding underscores the importance of maintaining lost weight and avoiding weight fluctuation. PMID:26953120
Khoshkholgh, Mehri Javan; Marsusi, Farah; Abolhassani, Mohammad Reza
2015-02-05
PTBs polymers with thieno[3,4-b]thiophene [TT] and benzodithiophene [BDT] units have particular properties, which demonstrate it as one of the best group of donor materials in organic solar cells. In the present work, density functional theory (DFT) is applied to investigate the optimized structure, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO), band gap and dihedral angle of PTB7 at B3LYP/6-31G(d). Two different approaches are applied to carry out these investigations: Oligomer extrapolation technique and periodic boundary condition (PBC) method. The results obtained from PBC-DFT method are in fair agreement with experiments. Based on these reliable outcomes; the investigations continued to perform some derivatives of PTB7. In this study, sulfur is substituted by nitrogen, oxygen, silicon, phosphor or selenium atoms in pristine PTB7. Due to the shift of HOMO and LUMO levels, smaller band gaps are predicted to appear in some derivatives in comparison with PTB7. Maximum theoretical efficiencies, η, of the mentioned derivatives as well as local difference of dipole moments between the ground and excited states (Δμge) are computed. The results indicate that substitution of sulfur by nitrogen or oxygen in BDT unit, and silicon or phosphor in TT unit of pristine PTB7 leads to a higher η as well as Δμge. Copyright © 2014 Elsevier B.V. All rights reserved.
Wang, Jia; Liu, Ru-De; Ding, Yi; Liu, Ying; Xu, Le; Zhen, Rui
2017-01-01
This study investigated how and why Chinese adolescents choose between playing online games and doing homework, using the model of the theory of planned behavior (TPB) in which the subjective norm was manipulated as two sub-elements (peer support and parental monitoring). A total of 530 students from an elementary school and a middle school in China were asked to complete the measures assessing two predictors of TPB: attitude and perceived behavioral control (PBC). Next, they completed a survey about their choice intention between playing an online game and doing homework in three different situations, wherein a conflict between playing online games and doing homework was introduced and subjective norm was manipulated as peers supporting and parents objecting to playing online games. The results showed that adolescents' attitude and PBC, as well as the perception of obtaining or not obtaining support from their peers and caregivers (manipulated subjective norm), significantly influenced their choice intention in online gaming situations. These findings contribute to the understanding of the factors affecting adolescents' online gaming, which has been a concern of both caregivers and educators. With regard to the theoretical implications, this study extended previous work by providing evidence that TPB can be applied to analyze choice intention. Moreover, this study illuminated the effects of the separating factors of subjective norm on choice intention between playing online games and studying.
Andrew, Benjamin J; Mullan, Barbara A; de Wit, John B F; Monds, Lauren A; Todd, Jemma; Kothe, Emily J
2016-12-01
The aim of this meta-analysis was to explore whether the constructs in the theory of planned behaviour (TPB; i.e., attitude, subjective norm, perceived behavioural control, intention) explain condom use behaviour among men who have sex with men (MSM). Electronic databases were searched for studies that measured TPB variables and MSM condom use. Correlations were meta-analysed using a random effects model and path analyses. Moderation analyses were conducted for the time frame of the behavioural measure used (retrospective versus prospective). Attitude, subjective norm and perceived behavioural control accounted for 24.0 % of the variance in condom use intention and were all significant correlates. Intention and PBC accounted for 12.4 % of the variance in condom use behaviour. However, after taking intention into account, PBC was no longer significantly associated with condom use. The strength of construct relationships did not differ between retrospective and prospective behavioural assessments. The medium to large effect sizes of the relationships between the constructs in the TPB, which are consistent with previous meta-analyses with different behaviours or target groups, suggest that the TPB is also a useful model for explaining condom use behaviour among MSM. However, the research in this area is rather small, and greater clarity over moderating factors can only be achieved when the literature expands.
Galaviz, K I; Jauregui-Ulloa, E; Fabrigar, L R; Latimer-Cheung, A; Lopez y Taylor, J; Lévesque, L
2015-03-01
To describe the physical activity (PA) prescribing behaviour of Mexican primary care physicians and determine if the theory of planned behaviour (TPB) explains this behaviour. 633 physicians (56% male, mean age 38 years) from 305 primary care clinics in Jalisco, Mexico self-reported PA prescription behaviour, PA involvement, attitude, subjective norm, perceived behavioural control (PBC) and intention related to PA prescription behaviour. Structural equation modelling (SEM) was employed. 48% of physicians reported they always ask patients about their PA, 33% provide verbal prescriptions, 6% provide written prescriptions, 8% refer patients to PA resources and 4% assess patient fitness. SEM analysis showed that the fit of the TPB model was satisfactory (RMSEA = 0.05, CFI = 0.98, SRMR = 0.05). The model explained 79% of the variance on intention (r(2) = 0.79, p < 0.05), and 14% of the variance on prescription behaviour (r(2) = 0.14, p < 0.05). Subjective norm (β = 0.73, p < 0.05) and attitude (β = 0.16, p < 0.05) explained behavioural intention, while PBC (β = 0.38, p < 0.05) and physician PA (β = 0.15, p < 0.05) explained prescription behaviour. The TPB provided useful insight into physician prescription behaviour, although not all the theory tenets were supported. More research testing the TPB and other theories is needed to better understand psychosocial predictors of this behaviour. Strategies aimed at improving physicians' perceived ability to prescribe PA and their own PA involvement seem worthwhile. © 2015 John Wiley & Sons Ltd.
Angiogenesis and proliferation of bile duct enhances ischemic tolerance in rats with cirrhosis
Zhang, Zhiqiang; Li, Zhennan; Zou, Chen; Zhang, Jingjing; Zhu, Yi; Miao, Yi
2015-01-01
Background/aims: Primary biliary cirrhosis (PBC), an autoimmune disease of the liver, is marked by slow progressive destruction of bile ducts. These patients with PBC often undergo orthotopic liver transplantation (OLT). Ischemic bile duct lesion (IBDL) is a major source of morbidity and even mortality after OLT. Cirrhosis of the liver has a higher tolerance to ischemia than a normal liver, but the mechanism remains unknown. Angiogenesis and proliferation of bile duct often responses in bile duct ischemia, which may enhance ischemic tolerance in patients with cirrhosis. Methodology: To test the hypothesis, a rat model with cirrhosis was established. Biochemical indexes of ischemic severity were measured including total bilirubin (TBIL) and direct bilirubin (DBIL). Immunohistochemical assay was performed for Ki67 (a biomarker for the proliferation of bile duct) and CD34 (a biomarker of angiogenesis). Results: The levels were lower for TBIL and DBIL in the bile duct from rat model with cirrhosis than that from a normal rat after ischemic surgery (P < 0.05). The levels were higher for Ki67 and CD34 from a rat model with cirrhosis than that from a normal rat after ischemic surgery (P < 0.05). Conclusions: The results suggest that a liver with cirrhosis has a better ischemic tolerance than a normal liver. Angiogenesis and proliferation of bile duct enhances ischemic tolerance in rats with cirrhosis. More research on the pathogenesis of IBDLs is needed for developing more specific preventive or therapeutic strategies. PMID:26550120
Research on Factors Influencing Individual's Behavior of Energy Management
NASA Astrophysics Data System (ADS)
Fan, Yanfeng
With the rapid rise of distributed generation, Internet of Things, and mobile Internet, both U.S. and European smart home manufacturers have developed energy management solutions for individual usage. These applications help people manage their energy consumption more efficiently. Domestic manufacturers have also launched similar products. This paper focuses on the factors influencing Energy Management Behaviour (EMB) at the individual level. By reviewing academic literature, conducting surveys in Beijing, Shanghai and Guangzhou, the author builds an integrated behavioural energy management model of the Chinese energy consumers. This paper takes the vague term of EMB and redefines it as a function of two separate behavioural concepts: Energy Management Intention (EMI), and the traditional Energy Saving Intention (ESI). Secondly, the author conducts statistical analyses on these two behavioural concepts. EMI is the main driver behind an individual's EMB. EMI is affected by Behavioural Attitudes, Subjective Norms, and Perceived Behavioural Control (PBC). Among these three key factors, PBC exerts the strongest influence. This implies that the promotion of the energy management concept is mainly driven by good application user experience (UX). The traditional ESI also demonstrates positive influence on EMB, but its impact is weaker than the impacts arising under EMI's three factors. In other words, the government and manufacturers may not be able to change an individual's energy management behaviour if they rely solely on their traditional promotion strategies. In addition, the study finds that the government may achieve better promotional results by launching subsidies to the manufacturers of these kinds of applications and smart appliances.
NASA Astrophysics Data System (ADS)
Karakurt, Tuncay; Cukurovali, Alaaddin; Subasi, Nuriye Tuna; Onaran, Abdurrahman; Ece, Abdulilah; Eker, Sıtkı; Kani, Ibrahim
2018-02-01
In the present study, a single crystal of a Schiff base, 2,2‧(hydrazine-1,2-diylidenebis(propan-1-yl-1-ylidene))diphenol, was synthesized. The structure of the synthesized crystal was confirmed by 1H and 13C NMR spectroscopic and X-ray diffraction analysis techniques. Experimental and theoretical studies were carried out on two tautomeric structures. It has been observed that the title compound studied can be in two different tautomeric forms, phenol-imine and keto-amine. Theoretical calculations have been performed to support experimental results. Accordingly, the geometric parameters of the compound were optimized by the density functional theory (DFT) method using the Gaussian 09 and Quantum Espresso (QE) packet program was used for periodic boundary conditions (PBC) studies. Furthermore, the compound was also tested for in vitro antifungal activity against Sclerotinia sclerotiorum, Alternaria solani, Fusarium oxysporum f. sp. lycopersici and Monilinia fructigena plant pathogens. Promising inhibition profiles were observed especially towards A. solani. Finally, molecular docking studies and post-docking procedure based on Molecular Mechanics-Generalized Born Surface Area (MM-GBSA) were also carried out to get insight into the compound's binding interactions with the potential. Although theoretical calculations showed that the phenol-imine form was more stable, keto-amine form was predicted to have better binding affinity which was concluded to result from loss of rotational entropy in phenol-imine upon binding. The results obtained here from both experimental and computational methods might serve as a potential lead in the development of novel anti-fungal agents.
d'plus: A program to calculate accuracy and bias measures from detection and discrimination data.
Macmillan, N A; Creelman, C D
1997-01-01
The program d'plus calculates accuracy (sensitivity) and response-bias parameters using Signal Detection Theory. Choice Theory, and 'nonparametric' models. is is appropriate for data from one-interval, two- and three-interval forced-choice, same different, ABX, and oddity experimental paradigms.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huang, J; Followill, D; Howell, R
2015-06-15
Purpose: To investigate two strategies for reducing dose calculation errors near metal implants: use of CT metal artifact reduction methods and implementation of metal-based energy deposition kernels in the convolution/superposition (C/S) method. Methods: Radiochromic film was used to measure the dose upstream and downstream of titanium and Cerrobend implants. To assess the dosimetric impact of metal artifact reduction methods, dose calculations were performed using baseline, uncorrected images and metal artifact reduction Methods: Philips O-MAR, GE’s monochromatic gemstone spectral imaging (GSI) using dual-energy CT, and GSI imaging with metal artifact reduction software applied (MARs).To assess the impact of metal kernels, titaniummore » and silver kernels were implemented into a commercial collapsed cone C/S algorithm. Results: The CT artifact reduction methods were more successful for titanium than Cerrobend. Interestingly, for beams traversing the metal implant, we found that errors in the dimensions of the metal in the CT images were more important for dose calculation accuracy than reduction of imaging artifacts. The MARs algorithm caused a distortion in the shape of the titanium implant that substantially worsened the calculation accuracy. In comparison to water kernel dose calculations, metal kernels resulted in better modeling of the increased backscatter dose at the upstream interface but decreased accuracy directly downstream of the metal. We also found that the success of metal kernels was dependent on dose grid size, with smaller calculation voxels giving better accuracy. Conclusion: Our study yielded mixed results, with neither the metal artifact reduction methods nor the metal kernels being globally effective at improving dose calculation accuracy. However, some successes were observed. The MARs algorithm decreased errors downstream of Cerrobend by a factor of two, and metal kernels resulted in more accurate backscatter dose upstream of metals. Thus, these two strategies do have the potential to improve accuracy for patients with metal implants in certain scenarios. This work was supported by Public Health Service grants CA 180803 and CA 10953 awarded by the National Cancer Institute, United States of Health and Human Services, and in part by Mobius Medical Systems.« less
Mazhab-Jafari, Mohammad T; Das, Rahul; Fotheringham, Steven A; SilDas, Soumita; Chowdhury, Somenath; Melacini, Giuseppe
2007-11-21
cAMP (adenosine 3',5'-cyclic monophosphate) is a ubiquitous second messenger that activates a multitude of essential cellular responses. Two key receptors for cAMP in eukaryotes are protein kinase A (PKA) and the exchange protein directly activated by cAMP (EPAC), which is a recently discovered guanine nucleotide exchange factor (GEF) for the small GTPases Rap1 and Rap2. Previous attempts to investigate the mechanism of allosteric activation of eukaryotic cAMP-binding domains (CBDs) at atomic or residue resolution have been hampered by the instability of the apo form, which requires the use of mixed apo/holo systems, that have provided only a partial picture of the CBD apo state and of the allosteric networks controlled by cAMP. Here, we show that, unlike other eukaryotic CBDs, both apo and cAMP-bound states of the EPAC1 CBD are stable under our experimental conditions, providing a unique opportunity to define at an unprecedented level of detail the allosteric interactions linking two critical functional sites of this CBD. These are the phosphate binding cassette (PBC), where cAMP binds, and the N-terminal helical bundle (NTHB), which is the site of the inhibitory interactions between the regulatory and catalytic regions of EPAC. Specifically, the combined analysis of the cAMP-dependent changes in chemical shifts, 2 degrees structure probabilities, hydrogen/hydrogen exchange (H/H) and hydrogen/deuterium exchange (H/D) protection factors reveals that the long-range communication between the PBC and the NTHB is implemented by two distinct intramolecular cAMP-signaling pathways, respectively, mediated by the beta2-beta3 loop and the alpha6 helix. Docking of cAMP into the PBC perturbs the NTHB inner core packing and the helical probabilities of selected NTHB residues. The proposed model is consistent with the allosteric role previously hypothesized for L273 and F300 based on site-directed mutagenesis; however, our data show that such a contact is part of a significantly more extended allosteric network that, unlike PKA, involves a tight coupling between the alpha- and beta-subdomains of the EPAC CBD. The proposed mechanism of allosteric activation will serve as a basis to understand agonism and antagonism in the EPAC system and provides also a general paradigm for how small ligands control protein-protein interfaces.
NASA Astrophysics Data System (ADS)
Beecken, B. P.; Fossum, E. R.
1996-07-01
Standard statistical theory is used to calculate how the accuracy of a conversion-gain measurement depends on the number of samples. During the development of a theoretical basis for this calculation, a model is developed that predicts how the noise levels from different elements of an ideal detector array are distributed. The model can also be used to determine what dependence the accuracy of measured noise has on the size of the sample. These features have been confirmed by experiment, thus enhancing the credibility of the method for calculating the uncertainty of a measured conversion gain. detector-array uniformity, charge coupled device, active pixel sensor.
Molecular dynamics study of some non-hydrogen-bonding base pair DNA strands
NASA Astrophysics Data System (ADS)
Tiwari, Rakesh K.; Ojha, Rajendra P.; Tiwari, Gargi; Pandey, Vishnudatt; Mall, Vijaysree
2018-05-01
In order to elucidate the structural activity of hydrophobic modified DNA, the DMMO2-D5SICS, base pair is introduced as a constituent in different set of 12-mer and 14-mer DNA sequences for the molecular dynamics (MD) simulation in explicit water solvent. AMBER 14 force field was employed for each set of duplex during the 200ns production-dynamics simulation in orthogonal-box-water solvent by the Particle-Mesh-Ewald (PME) method in infinite periodic boundary conditions (PBC) to determine conformational parameters of the complex. The force-field parameters of modified base-pair were calculated by Gaussian-code using Hartree-Fock /ab-initio methodology. RMSD Results reveal that the conformation of the duplex is sequence dependent and the binding energy of the complex depends on the position of the modified base-pair in the nucleic acid strand. We found that non-bonding energy had a significant contribution to stabilising such type of duplex in comparison to electrostatic energy. The distortion produced within strands by such type of base-pair was local and destabilised the duplex integrity near to substitution, moreover the binding energy of duplex depends on the position of substitution of hydrophobic base-pair and the DNA sequence and strongly supports the corresponding experimental study.
Amisaki, Takashi; Toyoda, Shinjiro; Miyagawa, Hiroh; Kitamura, Kunihiro
2003-04-15
Evaluation of long-range Coulombic interactions still represents a bottleneck in the molecular dynamics (MD) simulations of biological macromolecules. Despite the advent of sophisticated fast algorithms, such as the fast multipole method (FMM), accurate simulations still demand a great amount of computation time due to the accuracy/speed trade-off inherently involved in these algorithms. Unless higher order multipole expansions, which are extremely expensive to evaluate, are employed, a large amount of the execution time is still spent in directly calculating particle-particle interactions within the nearby region of each particle. To reduce this execution time for pair interactions, we developed a computation unit (board), called MD-Engine II, that calculates nonbonded pairwise interactions using a specially designed hardware. Four custom arithmetic-processors and a processor for memory manipulation ("particle processor") are mounted on the computation board. The arithmetic processors are responsible for calculation of the pair interactions. The particle processor plays a central role in realizing efficient cooperation with the FMM. The results of a series of 50-ps MD simulations of a protein-water system (50,764 atoms) indicated that a more stringent setting of accuracy in FMM computation, compared with those previously reported, was required for accurate simulations over long time periods. Such a level of accuracy was efficiently achieved using the cooperative calculations of the FMM and MD-Engine II. On an Alpha 21264 PC, the FMM computation at a moderate but tolerable level of accuracy was accelerated by a factor of 16.0 using three boards. At a high level of accuracy, the cooperative calculation achieved a 22.7-fold acceleration over the corresponding conventional FMM calculation. In the cooperative calculations of the FMM and MD-Engine II, it was possible to achieve more accurate computation at a comparable execution time by incorporating larger nearby regions. Copyright 2003 Wiley Periodicals, Inc. J Comput Chem 24: 582-592, 2003
Improved accuracy of intraocular lens power calculation with the Zeiss IOLMaster.
Olsen, Thomas
2007-02-01
This study aimed to demonstrate how the level of accuracy in intraocular lens (IOL) power calculation can be improved with optical biometry using partial optical coherence interferometry (PCI) (Zeiss IOLMaster) and current anterior chamber depth (ACD) prediction algorithms. Intraocular lens power in 461 consecutive cataract operations was calculated using both PCI and ultrasound and the accuracy of the results of each technique were compared. To illustrate the importance of ACD prediction per se, predictions were calculated using both a recently published 5-variable method and the Haigis 2-variable method and the results compared. All calculations were optimized in retrospect to account for systematic errors, including IOL constants and other off-set errors. The average absolute IOL prediction error (observed minus expected refraction) was 0.65 dioptres with ultrasound and 0.43 D with PCI using the 5-variable ACD prediction method (p < 0.00001). The number of predictions within +/- 0.5 D, +/- 1.0 D and +/- 2.0 D of the expected outcome was 62.5%, 92.4% and 99.9% with PCI, compared with 45.5%, 77.3% and 98.4% with ultrasound, respectively (p < 0.00001). The 2-variable ACD method resulted in an average error in PCI predictions of 0.46 D, which was significantly higher than the error in the 5-variable method (p < 0.001). The accuracy of IOL power calculation can be significantly improved using calibrated axial length readings obtained with PCI and modern IOL power calculation formulas incorporating the latest generation ACD prediction algorithms.
Sharma, Subhash; Ott, Joseph; Williams, Jamone; Dickow, Danny
2011-01-01
Monte Carlo dose calculation algorithms have the potential for greater accuracy than traditional model-based algorithms. This enhanced accuracy is particularly evident in regions of lateral scatter disequilibrium, which can develop during treatments incorporating small field sizes and low-density tissue. A heterogeneous slab phantom was used to evaluate the accuracy of several commercially available dose calculation algorithms, including Monte Carlo dose calculation for CyberKnife, Analytical Anisotropic Algorithm and Pencil Beam convolution for the Eclipse planning system, and convolution-superposition for the Xio planning system. The phantom accommodated slabs of varying density; comparisons between planned and measured dose distributions were accomplished with radiochromic film. The Monte Carlo algorithm provided the most accurate comparison between planned and measured dose distributions. In each phantom irradiation, the Monte Carlo predictions resulted in gamma analysis comparisons >97%, using acceptance criteria of 3% dose and 3-mm distance to agreement. In general, the gamma analysis comparisons for the other algorithms were <95%. The Monte Carlo dose calculation algorithm for CyberKnife provides more accurate dose distribution calculations in regions of lateral electron disequilibrium than commercially available model-based algorithms. This is primarily because of the ability of Monte Carlo algorithms to implicitly account for tissue heterogeneities, density scaling functions; and/or effective depth correction factors are not required. Copyright © 2011 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.
Moms and Media: Exploring the Effects of Online Communication on Infant Feeding Practices.
McKeever, Robert; McKeever, Brooke W
2017-09-01
Using a survey of mothers with young children (N = 455), this study applies Fishbein and Ajzen's reasoned action approach (RAA) to examine the relationship between online communication and infant feeding practices. Contrary to expectations, attitudes, perceived normative pressure, and perceived behavioral control (PBC) did not fully mediate the relationship between time spent online and behavioral intentions. Our findings indicate a significant, direct, negative association between time spent online and breastfeeding intentions In this article, theoretical and practical implications for health communication are discussed.
1986-07-01
demonstrated that plasmid pLS20 of B. subtilis ( natto ) is capa le of promoting the transfer of pBC16 from B. subtilis to a variety of Bacillus s ecies...anthracis. Hofetver, results of recent experiments demonstrate that pL320, a 34-megadalton plasmid of B. subtilis ( natto ), is capable of promoting the...plasmid in Bacillus subtilis ( natto ).20 IV. Determination of the size of pX02 by restriction analysis-....... 24 V. Transfer of pXO1 by the B
Fuchs, Lynn S.; Gilbert, Jennifer K.; Powell, Sarah R.; Cirino, Paul T.; Fuchs, Douglas; Hamlett, Carol L.; Seethaler, Pamela M.; Tolar, Tammy D.
2016-01-01
The purpose of this study was to examine child-level pathways in development of pre-algebraic knowledge versus word-problem solving, while evaluating the contribution of calculation accuracy and fluency as mediators of foundational skills/processes. Children (n = 962; mean 7.60 years) were assessed on general cognitive processes and early calculation, word-problem, and number knowledge at start of grade 2; calculation accuracy and calculation fluency at end of grade 2; and pre-algebraic knowledge and word-problem solving at end of grade 4. Important similarities in pathways were identified, but path analysis also indicated that language comprehension is more critical for later word-problem solving than pre-algebraic knowledge. We conclude that pathways in development of these forms of 4th-grade mathematics performance are more alike than different, but demonstrate the need to fine-tune instruction for strands of the mathematics curriculum in ways that address individual students’ foundational mathematics skills or cognitive processes. PMID:27786534
Sample size in studies on diagnostic accuracy in ophthalmology: a literature survey.
Bochmann, Frank; Johnson, Zoe; Azuara-Blanco, Augusto
2007-07-01
To assess the sample sizes used in studies on diagnostic accuracy in ophthalmology. Design and sources: A survey literature published in 2005. The frequency of reporting calculations of sample sizes and the samples' sizes were extracted from the published literature. A manual search of five leading clinical journals in ophthalmology with the highest impact (Investigative Ophthalmology and Visual Science, Ophthalmology, Archives of Ophthalmology, American Journal of Ophthalmology and British Journal of Ophthalmology) was conducted by two independent investigators. A total of 1698 articles were identified, of which 40 studies were on diagnostic accuracy. One study reported that sample size was calculated before initiating the study. Another study reported consideration of sample size without calculation. The mean (SD) sample size of all diagnostic studies was 172.6 (218.9). The median prevalence of the target condition was 50.5%. Only a few studies consider sample size in their methods. Inadequate sample sizes in diagnostic accuracy studies may result in misleading estimates of test accuracy. An improvement over the current standards on the design and reporting of diagnostic studies is warranted.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Morley, Steven
The PyForecastTools package provides Python routines for calculating metrics for model validation, forecast verification and model comparison. For continuous predictands the package provides functions for calculating bias (mean error, mean percentage error, median log accuracy, symmetric signed bias), and for calculating accuracy (mean squared error, mean absolute error, mean absolute scaled error, normalized RMSE, median symmetric accuracy). Convenience routines to calculate the component parts (e.g. forecast error, scaled error) of each metric are also provided. To compare models the package provides: generic skill score; percent better. Robust measures of scale including median absolute deviation, robust standard deviation, robust coefficient ofmore » variation and the Sn estimator are all provided by the package. Finally, the package implements Python classes for NxN contingency tables. In the case of a multi-class prediction, accuracy and skill metrics such as proportion correct and the Heidke and Peirce skill scores are provided as object methods. The special case of a 2x2 contingency table inherits from the NxN class and provides many additional metrics for binary classification: probability of detection, probability of false detection, false alarm ration, threat score, equitable threat score, bias. Confidence intervals for many of these quantities can be calculated using either the Wald method or Agresti-Coull intervals.« less
New more accurate calculations of the ground state potential energy surface of H(3) (+).
Pavanello, Michele; Tung, Wei-Cheng; Leonarski, Filip; Adamowicz, Ludwik
2009-02-21
Explicitly correlated Gaussian functions with floating centers have been employed to recalculate the ground state potential energy surface (PES) of the H(3) (+) ion with much higher accuracy than it was done before. The nonlinear parameters of the Gaussians (i.e., the exponents and the centers) have been variationally optimized with a procedure employing the analytical gradient of the energy with respect to these parameters. The basis sets for calculating new PES points were guessed from the points already calculated. This allowed us to considerably speed up the calculations and achieve very high accuracy of the results.
Accuracy control in Monte Carlo radiative calculations
NASA Technical Reports Server (NTRS)
Almazan, P. Planas
1993-01-01
The general accuracy law that rules the Monte Carlo, ray-tracing algorithms used commonly for the calculation of the radiative entities in the thermal analysis of spacecraft are presented. These entities involve transfer of radiative energy either from a single source to a target (e.g., the configuration factors). or from several sources to a target (e.g., the absorbed heat fluxes). In fact, the former is just a particular case of the latter. The accuracy model is later applied to the calculation of some specific radiative entities. Furthermore, some issues related to the implementation of such a model in a software tool are discussed. Although only the relative error is considered through the discussion, similar results can be derived for the absolute error.
Mathisen, R W; Mazess, R B
1981-02-01
The authors present a revised method for calculating life expectancy tables for populations where individual ages at death are known or can be estimated. The conventional and revised methods are compared using data for U.S. and Hungarian males in an attempt to determine the accuracy of each method in calculating life expectancy at advanced ages. Means of correcting errors caused by age rounding, age exaggeration, and infant mortality are presented
NASA Astrophysics Data System (ADS)
Kamal, Muhammad; Johansen, Kasper
2017-10-01
Effective mangrove management requires spatially explicit information of mangrove tree crown map as a basis for ecosystem diversity study and health assessment. Accuracy assessment is an integral part of any mapping activities to measure the effectiveness of the classification approach. In geographic object-based image analysis (GEOBIA) the assessment of the geometric accuracy (shape, symmetry and location) of the created image objects from image segmentation is required. In this study we used an explicit area-based accuracy assessment to measure the degree of similarity between the results of the classification and reference data from different aspects, including overall quality (OQ), user's accuracy (UA), producer's accuracy (PA) and overall accuracy (OA). We developed a rule set to delineate the mangrove tree crown using WorldView-2 pan-sharpened image. The reference map was obtained by visual delineation of the mangrove tree crowns boundaries form a very high-spatial resolution aerial photograph (7.5cm pixel size). Ten random points with a 10 m radius circular buffer were created to calculate the area-based accuracy assessment. The resulting circular polygons were used to clip both the classified image objects and reference map for area comparisons. In this case, the area-based accuracy assessment resulted 64% and 68% for the OQ and OA, respectively. The overall quality of the calculation results shows the class-related area accuracy; which is the area of correctly classified as tree crowns was 64% out of the total area of tree crowns. On the other hand, the overall accuracy of 68% was calculated as the percentage of all correctly classified classes (tree crowns and canopy gaps) in comparison to the total class area (an entire image). Overall, the area-based accuracy assessment was simple to implement and easy to interpret. It also shows explicitly the omission and commission error variations of object boundary delineation with colour coded polygons.
Tahmasbi, Amir; Ward, E. Sally; Ober, Raimund J.
2015-01-01
Fluorescence microscopy is a photon-limited imaging modality that allows the study of subcellular objects and processes with high specificity. The best possible accuracy (standard deviation) with which an object of interest can be localized when imaged using a fluorescence microscope is typically calculated using the Cramér-Rao lower bound, that is, the inverse of the Fisher information. However, the current approach for the calculation of the best possible localization accuracy relies on an analytical expression for the image of the object. This can pose practical challenges since it is often difficult to find appropriate analytical models for the images of general objects. In this study, we instead develop an approach that directly uses an experimentally collected image set to calculate the best possible localization accuracy for a general subcellular object. In this approach, we fit splines, i.e. smoothly connected piecewise polynomials, to the experimentally collected image set to provide a continuous model of the object, which can then be used for the calculation of the best possible localization accuracy. Due to its practical importance, we investigate in detail the application of the proposed approach in single molecule fluorescence microscopy. In this case, the object of interest is a point source and, therefore, the acquired image set pertains to an experimental point spread function. PMID:25837101
Jalambadani, Zeinab; Garmaroudi, Gholamreza; Tavousi, Mahmood
2018-01-01
Sexual function in patients with breast cancer, especially in younger patients, is an important issue from clinical and psychosocial perspectives. Theory of planned behavior (TPB) is one of the important theories that explain the main process of adopting healthy behaviors. This study investigated the effect of education based on TPB on sexual function of women with breast cancer in Mashhad, Iran. In this quasi-experimental study, 120 women (60 women in education group, 60 women in control group) visiting Razavi Hospital of Mashhad city were studied, selected by using the random method in 2016. The data collection tool was a questionnaire which was completed during the interview. The validity and reliability of this questionnaire were determined through the face and content validity and through Cronbach's alpha and test-retest, respectively. Data were analyzed using statistical SPSS 22 software. Using linear regression analysis, it was determined that attitudes, subjective norm, and perceived behavioral control (PBC) predict 0.85 overall of the total variance of sexual function intention, which among these variables, the effect of the subjective norm was more than the other ones ( P < 0.05). After educational intervention, the average rates of knowledge, attitude, PBC, and intention of sexual function in sex education group were significantly increased ( P < 0.05); these changes were not meaningful in the control group. There was no statistically significant difference in subjective norm between the two groups after intervention. The results of this research suggest that TPB can be used in sex education interventions and have relevant results.
Hyde, Melissa K; White, Katherine M
2010-05-01
To explore whether people's organ donation consent decisions occur via a reasoned and/or social reaction pathway. We examined prospectively students' and community members' decisions to register consent on a donor register and discuss organ donation wishes with family. Participants completed items assessing theory of planned behaviour (TPB; attitude, subjective norm, perceived behavioural control (PBC)), prototype/willingness model (PWM; donor prototype favourability/similarity, past behaviour), and proposed additional influences (moral norm, self-identity, recipient prototypes) for registering (N=339) and discussing (N=315) intentions/willingness. Participants self-reported their registering (N=177) and discussing (N=166) behaviour 1 month later. The utility of the (1) TPB, (2) PWM, (3) augmented TPB with PWM, and (4) augmented TPB with PWM and extensions was tested using structural equation modelling for registering and discussing intentions/willingness, and logistic regression for behaviour. While the TPB proved a more parsimonious model, fit indices suggested that the other proposed models offered viable options, explaining greater variance in communication intentions/willingness. The TPB, augmented TPB with PWM, and extended augmented TPB with PWM best explained registering and discussing decisions. The proposed and revised PWM also proved an adequate fit for discussing decisions. Respondents with stronger intentions (and PBC for registering) had a higher likelihood of registering and discussing. People's decisions to communicate donation wishes may be better explained via a reasoned pathway (especially for registering); however, discussing involves more reactive elements. The role of moral norm, self-identity, and prototypes as influences predicting communication decisions were highlighted also.
Koo, Eva; Henderson, Michael A; Dwyer, Mary; Skandarajah, Anita R
2015-12-01
Women treated with chest irradiation for childhood, adolescent, and young adulthood (CAYA) malignancies, in particular Hodgkin's lymphoma, have an increased risk of developing second cancers of the breast (SCB). However, there are few uniform guidelines regarding surveillance and prevention for this high-risk group. A systematic search using PUBMED and OVID MEDLINE was performed. Publications listed under the terms "breast neoplasm", "neoplasm, radiation-induced", "therapeutic radiation-induced breast cancer", "screening", "surveillance", "prevention", and "prophylaxis" between January 1992 and January 2015 were assessed. A total of 138 publications were reviewed. Factors associated with increased SCB risk include young age at irradiation, prolong duration since irradiation (peak relative risk 13.87 at 15-19 years postradiation), and increased radiation dose and field. Early menopause reduces SCB risk. Annual screening mammography and breast MRI is recommended from age 25 or 8 years posttreatment for women treated with ≥20 Gy chest radiation before age 30 years. Compared with sporadic primary breast cancers (PBC), SCB more often are bilateral (6-34 %), managed with mastectomy (56-100 %), hormone receptor-negative (27-49 %), and high-grade (35 %). Women with SCB have a similar breast cancer event-free survival and breast cancer-specific survival compared to women with PBC. However, their overall survival is worse due to comorbid conditions. There is paucity of information regarding secondary prevention of SCB. Survivors of CAYA malignancy are at risk of many late effects, including iatrogenic breast cancer from chest irradiation. They are best managed in a multidisciplinary late-effects setting where tailored risk management can be provided.
Bone mineral density before and after OLT: long-term follow-up and predictive factors.
Guichelaar, Maureen M J; Kendall, Rebecca; Malinchoc, Michael; Hay, J Eileen
2006-09-01
Fracturing after liver transplantation (OLT) occurs due to the combination of preexisting low bone mineral density (BMD) and early posttransplant bone loss, the risk factors for which are poorly defined. The prevalence and predictive factors for hepatic osteopenia and osteoporosis, posttransplant bone loss, and subsequent bone gain were studied by the long-term posttransplant follow-up of 360 consecutive adult patients with end-stage primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC). Only 20% of patients with advanced PBC or PSC have normal bone mass. Risk factors for low spinal BMD are low body mass index, older age, postmenopausal status, muscle wasting, high alkaline phosphatase and low serum albumin. A high rate of spinal bone loss occurred in the first 4 posttransplant months (annual rate of 16%) especially in those with younger age, PSC, higher pretransplant bone density, no inflammatory bowel disease, shorter duration of liver disease, current smoking, and ongoing cholestasis at 4 months. Factors favoring spinal bone gain from 4 to 24 months after transplantation were lower baseline and/or 4-month bone density, premenopausal status, lower cumulative glucocorticoids, no ongoing cholestasis, and higher levels of vitamin D and parathyroid hormone. Bone mass therefore improves most in patients with lowest pretransplant BMD who undergo successful transplantation with normal hepatic function and improved gonadal and nutritional status. Patients transplanted most recently have improved bone mass before OLT, and although bone loss still occurs early after OLT, these patients also have a greater recovery in BMD over the years following OLT.
Gui, Tao; Liu, Xing; Tao, Jia; Chen, Jianwen; Li, Yunsheng; Zhang, Meiling; Wu, Ronghua; Zhang, Yuanliang; Peng, Kaisong; Liu, Ya; Zhang, Xiaorong; Zhang, Yunhai
2013-12-01
Human bactericidal/permeability-increasing protein (hBPI) is the only antibacterial peptide which acts against both gram-negative bacteria and neutralizes endotoxins in human polymorphonuclear neutrophils; therefore, hBPI is of great value in clinical applications. In the study, we constructed a hBPI expression vector (pBC1-Loxp-Neo-Loxp-hBPI) containing the full-length hBPI coding sequence which could be specifically expressed in the mammary gland. To validate the function of the vector, in vitro cultured C127 (mouse mammary Carcinoma Cells) were transfected with the vector, and the transgenic cell clones were selected to express hBPI by hormone induction. The mRNA and protein expression of hBPI showed that the constructed vector was effective and suitable for future application in producing mammary gland bioreactor. Then, female and male goat fibroblasts were transfected with the vector, and two male and two female transgenic clonal cell lines were obtained. Using the transgenic cell lines as nuclear donors for somatic cell nuclear transfer, the reconstructed goat embryos produced from all four clones could develop to blastocysts in vitro. In conclusion, we constructed and validated an efficient mammary gland-specific hBPI expression vector, pBC1-Loxp-Neo-Loxp-hBPI, and transgenic hBPI goat embryos were successfully produced, laying foundations for future production of recombinant hBPI in goat mammary gland. Copyright © 2013 Elsevier B.V. All rights reserved.
Comparing solutions to the expectancy-value muddle in the theory of planned behaviour.
O' Sullivan, B; McGee, H; Keegan, O
2008-11-01
The authors of the Theories of Reasoned Action (TRA) and Planned Behaviour (TPB) recommended a method for statistically analysing the relationship between the indirect belief-based measures and the direct measures of attitude, subjective norm, and perceived behavioural control (PBC). However, there is a growing awareness that this yields statistically uninterpretable results. This study's objective was to compare two solutions to what has been called the 'expectancy-value muddle'. These solutions were (i) optimal scoring of modal beliefs and (ii) individual beliefs without multiplicative composites. Cross-sectional data were collected by telephone interview. Participants were 110 first-degree relatives (FDRs) of patients diagnosed with colorectal cancer (CRC), who were offered CRC screening in the study hospital (83% response rate). Participants were asked to rate the TPB constructs in relation to attending for CRC screening. There was no significant difference in the correlation between behavioural beliefs and attitude for rescaled modal and individual beliefs. This was also the case for control beliefs and PBC. By contrast, there was a large correlation between rescaled modal normative beliefs and subjective norm, whereas individual normative beliefs did not correlate with subjective norm. Using individual beliefs without multiplicative composites allows for a fairly unproblematic interpretation of the relationship between the indirect and direct TPB constructs (French & Hankins, 2003). Therefore, it is recommended that future studies consider using individual measures of behavioural and control beliefs without multiplicative composites and examine a different way of measuring individual normative beliefs without multiplicative composites to that used in this study.
Centromere Binding and Evolution of Chromosomal Partition Systems in the Burkholderiales
Passot, Fanny M.; Calderon, Virginie; Fichant, Gwennaele; Lane, David
2012-01-01
How split genomes arise and evolve in bacteria is poorly understood. Since each replicon of such genomes encodes a specific partition (Par) system, the evolution of Par systems could shed light on their evolution. The cystic fibrosis pathogen Burkholderia cenocepacia has three chromosomes (c1, c2, and c3) and one plasmid (pBC), whose compatibility depends on strictly specific interactions of the centromere sequences (parS) with their cognate binding proteins (ParB). However, the Par systems of B. cenocepacia c2, c3, and pBC share many features, suggesting that they arose within an extended family. Database searching revealed seven subfamilies of Par systems like those of B. cenocepacia. All are from plasmids and secondary chromosomes of the Burkholderiales, which reinforces the proposal of an extended family. The subfamily of the Par system of B. cenocepacia c3 includes plasmid variants with parS sequences divergent from that of c3. Using electrophoretic mobility shift assay (EMSA), we found that ParB-c3 binds specifically to centromeres of these variants, despite high DNA sequence divergence. We suggest that the Par system of B. cenocepacia c3 has preserved the features of an ancestral system. In contrast, these features have diverged variably in the plasmid descendants. One such descendant is found both in Ralstonia pickettii 12D, on a free plasmid, and in Ralstonia pickettii 12J, on a plasmid integrated into the main chromosome. These observations suggest that we are witnessing a plasmid-chromosome interaction from which a third chromosome will emerge in a two-chromosome species. PMID:22522899
Centromere binding and evolution of chromosomal partition systems in the Burkholderiales.
Passot, Fanny M; Calderon, Virginie; Fichant, Gwennaele; Lane, David; Pasta, Franck
2012-07-01
How split genomes arise and evolve in bacteria is poorly understood. Since each replicon of such genomes encodes a specific partition (Par) system, the evolution of Par systems could shed light on their evolution. The cystic fibrosis pathogen Burkholderia cenocepacia has three chromosomes (c1, c2, and c3) and one plasmid (pBC), whose compatibility depends on strictly specific interactions of the centromere sequences (parS) with their cognate binding proteins (ParB). However, the Par systems of B. cenocepacia c2, c3, and pBC share many features, suggesting that they arose within an extended family. Database searching revealed seven subfamilies of Par systems like those of B. cenocepacia. All are from plasmids and secondary chromosomes of the Burkholderiales, which reinforces the proposal of an extended family. The subfamily of the Par system of B. cenocepacia c3 includes plasmid variants with parS sequences divergent from that of c3. Using electrophoretic mobility shift assay (EMSA), we found that ParB-c3 binds specifically to centromeres of these variants, despite high DNA sequence divergence. We suggest that the Par system of B. cenocepacia c3 has preserved the features of an ancestral system. In contrast, these features have diverged variably in the plasmid descendants. One such descendant is found both in Ralstonia pickettii 12D, on a free plasmid, and in Ralstonia pickettii 12J, on a plasmid integrated into the main chromosome. These observations suggest that we are witnessing a plasmid-chromosome interaction from which a third chromosome will emerge in a two-chromosome species.
Gheorghe, Liana; Iacob, Speranta; Gheorghe, Cristian; Iacob, Razvan; Simionov, Iulia; Vadan, Roxana; Becheanu, Gabriel; Parvulescu, Iuliana; Toader, Cristina
2004-06-01
To evaluate the frequency of cholestatic pattern in patients with autoimmune hepatitis (AIH) and to identify predictive factors associated with the development of the overlap syndrome. Eighty-two consecutive patients diagnosed with AIH at the referral centre between January 1998 and June 2002 were included in the study. The new scoring system modified by the International Autoimmune Hepatitis Group was used to classify patients as definite/probable. Overlap syndrome was considered when the patient had clinical, serological and histological characteristics of two conditions: AIH and primary biliary cirrhosis (PBC) or AIH and primary sclerosing cholangitis (PSC). From the 82 AIH patients (76 female and six male), 84.1% presented definite AIH (> 15 points) and 15.9% probable AIH (10 - 15 points). The frequency of the overlap syndrome was 20%: 13% with PBC and 7% with PSC. In the univariate analysis the overlap syndrome was associated with male gender (P = 0.01), age < 35 years (P < 0.0001), histopathological aspect of cholestasis (P < 0.0001), suboptimal response to treatment (P < 0.0001) and probable AIH (P < 0.0001). Age < 35 years, probable AIH and the absence of anti-nuclear antibody (ANA) have been identified as independent indicators of the overlap diagnosis by the logistic regression analysis. Patients with overlap syndrome between AIH and primary cholestatic liver disease are frequently diagnosed in clinical practice, representing 20% of AIH cases in our study. The independent predictive factors associated with the diagnosis of overlap syndrome are young age, ANA(-) profile, and probable diagnosis according with the scoring system for AIH.
Accuracy of Standing-Tree Volume Estimates Based on McClure Mirror Caliper Measurements
Noel D. Cost
1971-01-01
The accuracy of standing-tree volume estimates, calculated from diameter measurements taken by a mirror caliper and with sectional aluminum poles for height control, was compared with volume estimates calculated from felled-tree measurements. Twenty-five trees which varied in species, size, and form were used in the test. The results showed that two estimates of total...
ERIC Educational Resources Information Center
Fuchs, Lynn S.; Gilbert, Jennifer K.; Powell, Sarah R.; Cirino, Paul T.; Fuchs, Douglas; Hamlett, Carol L.; Seethaler, Pamela M.; Tolar, Tammy D.
2016-01-01
The purpose of this study was to examine child-level pathways in development of prealgebraic knowledge versus word-problem solving, while evaluating the contribution of calculation accuracy and fluency as mediators of foundational skills/processes. Children (n = 962; mean 7.60 years) were assessed on general cognitive processes and early…
Increasing Accuracy in Computed Inviscid Boundary Conditions
NASA Technical Reports Server (NTRS)
Dyson, Roger
2004-01-01
A technique has been devised to increase the accuracy of computational simulations of flows of inviscid fluids by increasing the accuracy with which surface boundary conditions are represented. This technique is expected to be especially beneficial for computational aeroacoustics, wherein it enables proper accounting, not only for acoustic waves, but also for vorticity and entropy waves, at surfaces. Heretofore, inviscid nonlinear surface boundary conditions have been limited to third-order accuracy in time for stationary surfaces and to first-order accuracy in time for moving surfaces. For steady-state calculations, it may be possible to achieve higher accuracy in space, but high accuracy in time is needed for efficient simulation of multiscale unsteady flow phenomena. The present technique is the first surface treatment that provides the needed high accuracy through proper accounting of higher-order time derivatives. The present technique is founded on a method known in art as the Hermitian modified solution approximation (MESA) scheme. This is because high time accuracy at a surface depends upon, among other things, correction of the spatial cross-derivatives of flow variables, and many of these cross-derivatives are included explicitly on the computational grid in the MESA scheme. (Alternatively, a related method other than the MESA scheme could be used, as long as the method involves consistent application of the effects of the cross-derivatives.) While the mathematical derivation of the present technique is too lengthy and complex to fit within the space available for this article, the technique itself can be characterized in relatively simple terms: The technique involves correction of surface-normal spatial pressure derivatives at a boundary surface to satisfy the governing equations and the boundary conditions and thereby achieve arbitrarily high orders of time accuracy in special cases. The boundary conditions can now include a potentially infinite number of time derivatives of surface-normal velocity (consistent with no flow through the boundary) up to arbitrarily high order. The corrections for the first-order spatial derivatives of pressure are calculated by use of the first-order time derivative velocity. The corrected first-order spatial derivatives are used to calculate the second- order time derivatives of velocity, which, in turn, are used to calculate the corrections for the second-order pressure derivatives. The process as described is repeated, progressing through increasing orders of derivatives, until the desired accuracy is attained.
Filter Tuning Using the Chi-Squared Statistic
NASA Technical Reports Server (NTRS)
Lilly-Salkowski, Tyler B.
2017-01-01
This paper examines the use of the Chi-square statistic as a means of evaluating filter performance. The goal of the process is to characterize the filter performance in the metric of covariance realism. The Chi-squared statistic is the value calculated to determine the realism of a covariance based on the prediction accuracy and the covariance values at a given point in time. Once calculated, it is the distribution of this statistic that provides insight on the accuracy of the covariance. The process of tuning an Extended Kalman Filter (EKF) for Aqua and Aura support is described, including examination of the measurement errors of available observation types, and methods of dealing with potentially volatile atmospheric drag modeling. Predictive accuracy and the distribution of the Chi-squared statistic, calculated from EKF solutions, are assessed.
Flux Renormalization in Constant Power Burnup Calculations
Isotalo, Aarno E.; Aalto Univ., Otaniemi; Davidson, Gregory G.; ...
2016-06-15
To more accurately represent the desired power in a constant power burnup calculation, the depletion steps of the calculation can be divided into substeps and the neutron flux renormalized on each substep to match the desired power. Here, this paper explores how such renormalization should be performed, how large a difference it makes, and whether using renormalization affects results regarding the relative performance of different neutronics–depletion coupling schemes. When used with older coupling schemes, renormalization can provide a considerable improvement in overall accuracy. With previously published higher order coupling schemes, which are more accurate to begin with, renormalization has amore » much smaller effect. Finally, while renormalization narrows the differences in the accuracies of different coupling schemes, their order of accuracy is not affected.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ali, Imad, E-mail: iali@ouhsc.edu; Ahmad, Salahuddin
2013-10-01
To compare the doses calculated using the BrainLAB pencil beam (PB) and Monte Carlo (MC) algorithms for tumors located in various sites including the lung and evaluate quality assurance procedures required for the verification of the accuracy of dose calculation. The dose-calculation accuracy of PB and MC was also assessed quantitatively with measurement using ionization chamber and Gafchromic films placed in solid water and heterogeneous phantoms. The dose was calculated using PB convolution and MC algorithms in the iPlan treatment planning system from BrainLAB. The dose calculation was performed on the patient's computed tomography images with lesions in various treatmentmore » sites including 5 lungs, 5 prostates, 4 brains, 2 head and necks, and 2 paraspinal tissues. A combination of conventional, conformal, and intensity-modulated radiation therapy plans was used in dose calculation. The leaf sequence from intensity-modulated radiation therapy plans or beam shapes from conformal plans and monitor units and other planning parameters calculated by the PB were identical for calculating dose with MC. Heterogeneity correction was considered in both PB and MC dose calculations. Dose-volume parameters such as V95 (volume covered by 95% of prescription dose), dose distributions, and gamma analysis were used to evaluate the calculated dose by PB and MC. The measured doses by ionization chamber and EBT GAFCHROMIC film in solid water and heterogeneous phantoms were used to quantitatively asses the accuracy of dose calculated by PB and MC. The dose-volume histograms and dose distributions calculated by PB and MC in the brain, prostate, paraspinal, and head and neck were in good agreement with one another (within 5%) and provided acceptable planning target volume coverage. However, dose distributions of the patients with lung cancer had large discrepancies. For a plan optimized with PB, the dose coverage was shown as clinically acceptable, whereas in reality, the MC showed a systematic lack of dose coverage. The dose calculated by PB for lung tumors was overestimated by up to 40%. An interesting feature that was observed is that despite large discrepancies in dose-volume histogram coverage of the planning target volume between PB and MC, the point doses at the isocenter (center of the lesions) calculated by both algorithms were within 7% even for lung cases. The dose distributions measured with EBT GAFCHROMIC films in heterogeneous phantoms showed large discrepancies of nearly 15% lower than PB at interfaces between heterogeneous media, where these lower doses measured by the film were in agreement with those by MC. The doses (V95) calculated by MC and PB agreed within 5% for treatment sites with small tissue heterogeneities such as the prostate, brain, head and neck, and paraspinal tumors. Considerable discrepancies, up to 40%, were observed in the dose-volume coverage between MC and PB in lung tumors, which may affect clinical outcomes. The discrepancies between MC and PB increased for 15 MV compared with 6 MV indicating the importance of implementation of accurate clinical treatment planning such as MC. The comparison of point doses is not representative of the discrepancies in dose coverage and might be misleading in evaluating the accuracy of dose calculation between PB and MC. Thus, the clinical quality assurance procedures required to verify the accuracy of dose calculation using PB and MC need to consider measurements of 2- and 3-dimensional dose distributions rather than a single point measurement using heterogeneous phantoms instead of homogenous water-equivalent phantoms.« less
A method of solid-solid phase equilibrium calculation by molecular dynamics
NASA Astrophysics Data System (ADS)
Karavaev, A. V.; Dremov, V. V.
2016-12-01
A method for evaluation of solid-solid phase equilibrium curves in molecular dynamics simulation for a given model of interatomic interaction is proposed. The method allows to calculate entropies of crystal phases and provides an accuracy comparable with that of the thermodynamic integration method by Frenkel and Ladd while it is much simpler in realization and less intense computationally. The accuracy of the proposed method was demonstrated in MD calculations of entropies for EAM potential for iron and for MEAM potential for beryllium. The bcc-hcp equilibrium curves for iron calculated for the EAM potential by the thermodynamic integration method and by the proposed one agree quite well.
Li, Hong Zhi; Tao, Wei; Gao, Ting; Li, Hui; Lu, Ying Hua; Su, Zhong Min
2011-01-01
We propose a generalized regression neural network (GRNN) approach based on grey relational analysis (GRA) and principal component analysis (PCA) (GP-GRNN) to improve the accuracy of density functional theory (DFT) calculation for homolysis bond dissociation energies (BDE) of Y-NO bond. As a demonstration, this combined quantum chemistry calculation with the GP-GRNN approach has been applied to evaluate the homolysis BDE of 92 Y-NO organic molecules. The results show that the ull-descriptor GRNN without GRA and PCA (F-GRNN) and with GRA (G-GRNN) approaches reduce the root-mean-square (RMS) of the calculated homolysis BDE of 92 organic molecules from 5.31 to 0.49 and 0.39 kcal mol(-1) for the B3LYP/6-31G (d) calculation. Then the newly developed GP-GRNN approach further reduces the RMS to 0.31 kcal mol(-1). Thus, the GP-GRNN correction on top of B3LYP/6-31G (d) can improve the accuracy of calculating the homolysis BDE in quantum chemistry and can predict homolysis BDE which cannot be obtained experimentally.
Performance Evaluation of sUAS Equipped with Velodyne HDL-32E LiDAR Sensor
NASA Astrophysics Data System (ADS)
Jozkow, G.; Wieczorek, P.; Karpina, M.; Walicka, A.; Borkowski, A.
2017-08-01
The Velodyne HDL-32E laser scanner is used more frequently as main mapping sensor in small commercial UASs. However, there is still little information about the actual accuracy of point clouds collected with such UASs. This work evaluates empirically the accuracy of the point cloud collected with such UAS. Accuracy assessment was conducted in four aspects: impact of sensors on theoretical point cloud accuracy, trajectory reconstruction quality, and internal and absolute point cloud accuracies. Theoretical point cloud accuracy was evaluated by calculating 3D position error knowing errors of used sensors. The quality of trajectory reconstruction was assessed by comparing position and attitude differences from forward and reverse EKF solution. Internal and absolute accuracies were evaluated by fitting planes to 8 point cloud samples extracted for planar surfaces. In addition, the absolute accuracy was also determined by calculating point 3D distances between LiDAR UAS and reference TLS point clouds. Test data consisted of point clouds collected in two separate flights performed over the same area. Executed experiments showed that in tested UAS, the trajectory reconstruction, especially attitude, has significant impact on point cloud accuracy. Estimated absolute accuracy of point clouds collected during both test flights was better than 10 cm, thus investigated UAS fits mapping-grade category.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Takahashi, R; Kamima, T; Tachibana, H
2015-06-15
Purpose: To show the results of a multi-institutional study of the independent dose verification for conventional, Stereotactic radiosurgery and body radiotherapy (SRS and SBRT) plans based on the action level of AAPM TG-114. Methods: This study was performed at 12 institutions in Japan. To eliminate the bias of independent dose verification program (Indp), all of the institutions used the same CT-based independent dose verification software (Simple MU Analysis, Triangle Products, JP) with the Clarkson-based algorithm. Eclipse (AAA, PBC), Pinnacle{sup 3} (Adaptive Convolve) and Xio (Superposition) were used as treatment planning system (TPS). The confidence limits (CL, Mean±2SD) for 18 sitesmore » (head, breast, lung, pelvis, etc.) were evaluated in comparison in dose between the TPS and the Indp. Results: A retrospective analysis of 6352 treatment fields was conducted. The CLs for conventional, SRS and SBRT were 1.0±3.7 %, 2.0±2.5 % and 6.2±4.4 %, respectively. In conventional plans, most of the sites showed within 5 % of TG-114 action level. However, there were the systematic difference (4.0±4.0 % and 2.5±5.8 % for breast and lung, respectively). In SRS plans, our results showed good agreement compared to the action level. In SBRT plans, the discrepancy between the Indp was variable depending on dose calculation algorithms of TPS. Conclusion: The impact of dose calculation algorithms for the TPS and the Indp affects the action level. It is effective to set the site-specific tolerances, especially for the site where inhomogeneous correction can affect dose distribution strongly.« less
Method of calculating tsunami travel times in the Andaman Sea region
Visuthismajarn, Parichart; Tanavud, Charlchai; Robson, Mark G.
2014-01-01
A new model to calculate tsunami travel times in the Andaman Sea region has been developed. The model specifically provides more accurate travel time estimates for tsunamis propagating to Patong Beach on the west coast of Phuket, Thailand. More generally, the model provides better understanding of the influence of the accuracy and resolution of bathymetry data on the accuracy of travel time calculations. The dynamic model is based on solitary wave theory, and a lookup function is used to perform bilinear interpolation of bathymetry along the ray trajectory. The model was calibrated and verified using data from an echosounder record, tsunami photographs, satellite altimetry records, and eyewitness accounts of the tsunami on 26 December 2004. Time differences for 12 representative targets in the Andaman Sea and the Indian Ocean regions were calculated. The model demonstrated satisfactory time differences (<2 min/h), despite the use of low resolution bathymetry (ETOPO2v2). To improve accuracy, the dynamics of wave elevation and a velocity correction term must be considered, particularly for calculations in the nearshore region. PMID:25741129
Fuchs, Lynn S; Gilbert, Jennifer K; Powell, Sarah R; Cirino, Paul T; Fuchs, Douglas; Hamlett, Carol L; Seethaler, Pamela M; Tolar, Tammy D
2016-12-01
The purpose of this study was to examine child-level pathways in development of prealgebraic knowledge versus word-problem solving, while evaluating the contribution of calculation accuracy and fluency as mediators of foundational skills/processes. Children (n = 962; mean 7.60 years) were assessed on general cognitive processes and early calculation, word-problem, and number knowledge at start of Grade 2; calculation accuracy and calculation fluency at end of Grade 2; and prealgebraic knowledge and word-problem solving at end of Grade 4. Important similarities in pathways were identified, but path analysis also indicated that language comprehension is more critical for later word-problem solving than prealgebraic knowledge. We conclude that pathways in development of these forms of 4th-grade mathematics performance are more alike than different, but demonstrate the need to fine-tune instruction for strands of the mathematics curriculum in ways that address individual students' foundational mathematics skills or cognitive processes. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Method of calculating tsunami travel times in the Andaman Sea region.
Kietpawpan, Monte; Visuthismajarn, Parichart; Tanavud, Charlchai; Robson, Mark G
2008-07-01
A new model to calculate tsunami travel times in the Andaman Sea region has been developed. The model specifically provides more accurate travel time estimates for tsunamis propagating to Patong Beach on the west coast of Phuket, Thailand. More generally, the model provides better understanding of the influence of the accuracy and resolution of bathymetry data on the accuracy of travel time calculations. The dynamic model is based on solitary wave theory, and a lookup function is used to perform bilinear interpolation of bathymetry along the ray trajectory. The model was calibrated and verified using data from an echosounder record, tsunami photographs, satellite altimetry records, and eyewitness accounts of the tsunami on 26 December 2004. Time differences for 12 representative targets in the Andaman Sea and the Indian Ocean regions were calculated. The model demonstrated satisfactory time differences (<2 min/h), despite the use of low resolution bathymetry (ETOPO2v2). To improve accuracy, the dynamics of wave elevation and a velocity correction term must be considered, particularly for calculations in the nearshore region.
40 CFR 63.8 - Monitoring requirements.
Code of Federal Regulations, 2010 CFR
2010-07-01
... in the relevant standard; or (B) The CMS fails a performance test audit (e.g., cylinder gas audit), relative accuracy audit, relative accuracy test audit, or linearity test audit; or (C) The COMS CD exceeds...) Data recording, calculations, and reporting; (v) Accuracy audit procedures, including sampling and...
Dose computation for therapeutic electron beams
NASA Astrophysics Data System (ADS)
Glegg, Martin Mackenzie
The accuracy of electron dose calculations performed by two commercially available treatment planning computers, Varian Cadplan and Helax TMS, has been assessed. Measured values of absorbed dose delivered by a Varian 2100C linear accelerator, under a wide variety of irradiation conditions, were compared with doses calculated by the treatment planning computers. Much of the motivation for this work was provided by a requirement to verify the accuracy of calculated electron dose distributions in situations encountered clinically at Glasgow's Beatson Oncology Centre. Calculated dose distributions are required in a significant minority of electron treatments, usually in cases involving treatment to the head and neck. Here, therapeutic electron beams are subject to factors which may cause non-uniformity in the distribution of dose, and which may complicate the calculation of dose. The beam shape is often irregular, the beam may enter the patient at an oblique angle or at an extended source to skin distance (SSD), tissue inhomogeneities can alter the dose distribution, and tissue equivalent material (such as wax) may be added to reduce dose to critical organs. Technological advances have allowed the current generation of treatment planning computers to implement dose calculation algorithms with the ability to model electron beams in these complex situations. These calculations have, however, yet to be verified by measurement. This work has assessed the accuracy of calculations in a number of specific instances. Chapter two contains a comparison of measured and calculated planar electron isodose distributions. Three situations were considered: oblique incidence, incidence on an irregular surface (such as that which would be arise from the use of wax to reduce dose to spinal cord), and incidence on a phantom containing a small air cavity. Calculations were compared with measurements made by thermoluminescent dosimetry (TLD) in a WTe electron solid water phantom. Chapter three assesses the planning computers' ability to model electron beam penumbra at extended SSD. Calculations were compared with diode measurements in a water phantom. Further measurements assessed doses in the junction region produced by abutting an extended SSD electron field with opposed photon fields. Chapter four describes an investigation of the size and shape of the region enclosed by the 90% isodose line when produced by limiting the electron beam with square and elliptical apertures. The 90% isodose line was chosen because clinical treatments are often prescribed such that a given volume receives at least 90% dose. Calculated and measured dose distributions were compared in a plane normal to the beam central axis. Measurements were made by film dosimetry. While chapters two to four examine relative doses, chapter five assesses the accuracy of absolute dose (or output) calculations performed by the planning computers. Output variation with SSD and field size was examined. Two further situations already assessed for the distribution of relative dose were also considered: an obliquely incident field, and a field incident on an irregular surface. The accuracy of calculations was assessed against criteria stipulated by the International Commission on Radiation Units and Measurement (ICRU). The Varian Cadplan and Helax TMS treatment planning systems produce acceptable accuracy in the calculation of relative dose from therapeutic electron beams in most commonly encountered situations. When interpreting clinical dose distributions, however, knowledge of the limitations of the calculation algorithm employed by each system is required in order to identify the minority of situations where results are not accurate. The calculation of absolute dose is too inaccurate to implement in a clinical environment. (Abstract shortened by ProQuest.).
Hirayama, Shusuke; Takayanagi, Taisuke; Fujii, Yusuke; Fujimoto, Rintaro; Fujitaka, Shinichiro; Umezawa, Masumi; Nagamine, Yoshihiko; Hosaka, Masahiro; Yasui, Keisuke; Omachi, Chihiro; Toshito, Toshiyuki
2016-03-01
The main purpose in this study was to present the results of beam modeling and how the authors systematically investigated the influence of double and triple Gaussian proton kernel models on the accuracy of dose calculations for spot scanning technique. The accuracy of calculations was important for treatment planning software (TPS) because the energy, spot position, and absolute dose had to be determined by TPS for the spot scanning technique. The dose distribution was calculated by convolving in-air fluence with the dose kernel. The dose kernel was the in-water 3D dose distribution of an infinitesimal pencil beam and consisted of an integral depth dose (IDD) and a lateral distribution. Accurate modeling of the low-dose region was important for spot scanning technique because the dose distribution was formed by cumulating hundreds or thousands of delivered beams. The authors employed a double Gaussian function as the in-air fluence model of an individual beam. Double and triple Gaussian kernel models were also prepared for comparison. The parameters of the kernel lateral model were derived by fitting a simulated in-water lateral dose profile induced by an infinitesimal proton beam, whose emittance was zero, at various depths using Monte Carlo (MC) simulation. The fitted parameters were interpolated as a function of depth in water and stored as a separate look-up table. These stored parameters for each energy and depth in water were acquired from the look-up table when incorporating them into the TPS. The modeling process for the in-air fluence and IDD was based on the method proposed in the literature. These were derived using MC simulation and measured data. The authors compared the measured and calculated absolute doses at the center of the spread-out Bragg peak (SOBP) under various volumetric irradiation conditions to systematically investigate the influence of the two types of kernel models on the dose calculations. The authors investigated the difference between double and triple Gaussian kernel models. The authors found that the difference between the two studied kernel models appeared at mid-depths and the accuracy of predicting the double Gaussian model deteriorated at the low-dose bump that appeared at mid-depths. When the authors employed the double Gaussian kernel model, the accuracy of calculations for the absolute dose at the center of the SOBP varied with irradiation conditions and the maximum difference was 3.4%. In contrast, the results obtained from calculations with the triple Gaussian kernel model indicated good agreement with the measurements within ±1.1%, regardless of the irradiation conditions. The difference between the results obtained with the two types of studied kernel models was distinct in the high energy region. The accuracy of calculations with the double Gaussian kernel model varied with the field size and SOBP width because the accuracy of prediction with the double Gaussian model was insufficient at the low-dose bump. The evaluation was only qualitative under limited volumetric irradiation conditions. Further accumulation of measured data would be needed to quantitatively comprehend what influence the double and triple Gaussian kernel models had on the accuracy of dose calculations.
Operations Guide for Civilian Manpower Costing. Part 2. Detailed Instructions.
1984-01-01
Q4Goete) Encl 3 Figure 2.1.5 (Cont.). PBC Mem ~o B4-55 (Repricing PDIPs) 2-35 ~.V COVER SHEET OFFICE SYMBOL DACA-OMP DATE 10 Feb 84 CON-AROL NUMBER...45d be ~ib4 5.. pmeew". o pmwoe (Cmem em o e* mem of 5-mi) PBS-FORDIMS FY 86-90 P0it, COB, OOC Live File See attached instruct.ions to update PBS...8217*. USMSSA DACA- OHP .. O&S AMT: Mr. Frank n.80 PBS- FORLD IS _________________________________ CSR 11-18 Production for FY 1985 OSD Budget___
DOE Office of Scientific and Technical Information (OSTI.GOV)
Han, C; Schultheiss, T
Purpose: In this study, we aim to evaluate the effect of dose grid size on the accuracy of calculated dose for small lesions in intracranial stereotactic radiosurgery (SRS), and to verify dose calculation accuracy with radiochromic film dosimetry. Methods: 15 intracranial lesions from previous SRS patients were retrospectively selected for this study. The planning target volume (PTV) ranged from 0.17 to 2.3 cm{sup 3}. A commercial treatment planning system was used to generate SRS plans using the volumetric modulated arc therapy (VMAT) technique using two arc fields. Two convolution-superposition-based dose calculation algorithms (Anisotropic Analytical Algorithm and Acuros XB algorithm) weremore » used to calculate volume dose distribution with dose grid size ranging from 1 mm to 3 mm with 0.5 mm step size. First, while the plan monitor units (MU) were kept constant, PTV dose variations were analyzed. Second, with 95% of the PTV covered by the prescription dose, variations of the plan MUs as a function of dose grid size were analyzed. Radiochomic films were used to compare the delivered dose and profile with the calculated dose distribution with different dose grid sizes. Results: The dose to the PTV, in terms of the mean dose, maximum, and minimum dose, showed steady decrease with increasing dose grid size using both algorithms. With 95% of the PTV covered by the prescription dose, the total MU increased with increasing dose grid size in most of the plans. Radiochromic film measurements showed better agreement with dose distributions calculated with 1-mm dose grid size. Conclusion: Dose grid size has significant impact on calculated dose distribution in intracranial SRS treatment planning with small target volumes. Using the default dose grid size could lead to under-estimation of delivered dose. A small dose grid size should be used to ensure calculation accuracy and agreement with QA measurements.« less
The Quality and Accuracy of Mobile Apps to Prevent Driving After Drinking Alcohol.
Wilson, Hollie; Stoyanov, Stoyan R; Gandabhai, Shailen; Baldwin, Alexander
2016-08-08
Driving after the consumption of alcohol represents a significant problem globally. Individual prevention countermeasures such as personalized mobile app aimed at preventing such behavior are widespread, but there is little research on their accuracy and evidence base. There has been no known assessment investigating the quality of such apps. This study aimed to determine the quality and accuracy of apps for drink driving prevention by conducting a review and evaluation of relevant mobile apps. A systematic app search was conducted following PRISMA guidelines. App quality was assessed using the Mobile App Rating Scale (MARS). Apps providing blood alcohol calculators (hereafter "calculators") were reviewed against current alcohol advice for accuracy. A total of 58 apps (30 iOS and 28 Android) met inclusion criteria and were included in the final analysis. Drink driving prevention apps had significantly lower engagement and overall quality scores than alcohol management apps. Most calculators provided conservative blood alcohol content (BAC) time until sober calculations. None of the apps had been evaluated to determine their efficacy in changing either drinking or driving behaviors. This novel study demonstrates that most drink driving prevention apps are not engaging and lack accuracy. They could be improved by increasing engagement features, such as gamification. Further research should examine the context and motivations for using apps to prevent driving after drinking in at-risk populations. Development of drink driving prevention apps should incorporate evidence-based information and guidance, lacking in current apps.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Y M; Bush, K; Han, B
Purpose: Accurate and fast dose calculation is a prerequisite of precision radiation therapy in modern photon and particle therapy. While Monte Carlo (MC) dose calculation provides high dosimetric accuracy, the drastically increased computational time hinders its routine use. Deterministic dose calculation methods are fast, but problematic in the presence of tissue density inhomogeneity. We leverage the useful features of deterministic methods and MC to develop a hybrid dose calculation platform with autonomous utilization of MC and deterministic calculation depending on the local geometry, for optimal accuracy and speed. Methods: Our platform utilizes a Geant4 based “localized Monte Carlo” (LMC) methodmore » that isolates MC dose calculations only to volumes that have potential for dosimetric inaccuracy. In our approach, additional structures are created encompassing heterogeneous volumes. Deterministic methods calculate dose and energy fluence up to the volume surfaces, where the energy fluence distribution is sampled into discrete histories and transported using MC. Histories exiting the volume are converted back into energy fluence, and transported deterministically. By matching boundary conditions at both interfaces, deterministic dose calculation account for dose perturbations “downstream” of localized heterogeneities. Hybrid dose calculation was performed for water and anthropomorphic phantoms. Results: We achieved <1% agreement between deterministic and MC calculations in the water benchmark for photon and proton beams, and dose differences of 2%–15% could be observed in heterogeneous phantoms. The saving in computational time (a factor ∼4–7 compared to a full Monte Carlo dose calculation) was found to be approximately proportional to the volume of the heterogeneous region. Conclusion: Our hybrid dose calculation approach takes advantage of the computational efficiency of deterministic method and accuracy of MC, providing a practical tool for high performance dose calculation in modern RT. The approach is generalizable to all modalities where heterogeneities play a large role, notably particle therapy.« less
SU-E-T-423: Fast Photon Convolution Calculation with a 3D-Ideal Kernel On the GPU
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moriya, S; Sato, M; Tachibana, H
Purpose: The calculation time is a trade-off for improving the accuracy of convolution dose calculation with fine calculation spacing of the KERMA kernel. We investigated to accelerate the convolution calculation using an ideal kernel on the Graphic Processing Units (GPU). Methods: The calculation was performed on the AMD graphics hardware of Dual FirePro D700 and our algorithm was implemented using the Aparapi that convert Java bytecode to OpenCL. The process of dose calculation was separated with the TERMA and KERMA steps. The dose deposited at the coordinate (x, y, z) was determined in the process. In the dose calculation runningmore » on the central processing unit (CPU) of Intel Xeon E5, the calculation loops were performed for all calculation points. On the GPU computation, all of the calculation processes for the points were sent to the GPU and the multi-thread computation was done. In this study, the dose calculation was performed in a water equivalent homogeneous phantom with 150{sup 3} voxels (2 mm calculation grid) and the calculation speed on the GPU to that on the CPU and the accuracy of PDD were compared. Results: The calculation time for the GPU and the CPU were 3.3 sec and 4.4 hour, respectively. The calculation speed for the GPU was 4800 times faster than that for the CPU. The PDD curve for the GPU was perfectly matched to that for the CPU. Conclusion: The convolution calculation with the ideal kernel on the GPU was clinically acceptable for time and may be more accurate in an inhomogeneous region. Intensity modulated arc therapy needs dose calculations for different gantry angles at many control points. Thus, it would be more practical that the kernel uses a coarse spacing technique if the calculation is faster while keeping the similar accuracy to a current treatment planning system.« less
Li, Hong Zhi; Hu, Li Hong; Tao, Wei; Gao, Ting; Li, Hui; Lu, Ying Hua; Su, Zhong Min
2012-01-01
A DFT-SOFM-RBFNN method is proposed to improve the accuracy of DFT calculations on Y-NO (Y = C, N, O, S) homolysis bond dissociation energies (BDE) by combining density functional theory (DFT) and artificial intelligence/machine learning methods, which consist of self-organizing feature mapping neural networks (SOFMNN) and radial basis function neural networks (RBFNN). A descriptor refinement step including SOFMNN clustering analysis and correlation analysis is implemented. The SOFMNN clustering analysis is applied to classify descriptors, and the representative descriptors in the groups are selected as neural network inputs according to their closeness to the experimental values through correlation analysis. Redundant descriptors and intuitively biased choices of descriptors can be avoided by this newly introduced step. Using RBFNN calculation with the selected descriptors, chemical accuracy (≤1 kcal·mol(-1)) is achieved for all 92 calculated organic Y-NO homolysis BDE calculated by DFT-B3LYP, and the mean absolute deviations (MADs) of the B3LYP/6-31G(d) and B3LYP/STO-3G methods are reduced from 4.45 and 10.53 kcal·mol(-1) to 0.15 and 0.18 kcal·mol(-1), respectively. The improved results for the minimal basis set STO-3G reach the same accuracy as those of 6-31G(d), and thus B3LYP calculation with the minimal basis set is recommended to be used for minimizing the computational cost and to expand the applications to large molecular systems. Further extrapolation tests are performed with six molecules (two containing Si-NO bonds and two containing fluorine), and the accuracy of the tests was within 1 kcal·mol(-1). This study shows that DFT-SOFM-RBFNN is an efficient and highly accurate method for Y-NO homolysis BDE. The method may be used as a tool to design new NO carrier molecules.
Li, Hong Zhi; Hu, Li Hong; Tao, Wei; Gao, Ting; Li, Hui; Lu, Ying Hua; Su, Zhong Min
2012-01-01
A DFT-SOFM-RBFNN method is proposed to improve the accuracy of DFT calculations on Y-NO (Y = C, N, O, S) homolysis bond dissociation energies (BDE) by combining density functional theory (DFT) and artificial intelligence/machine learning methods, which consist of self-organizing feature mapping neural networks (SOFMNN) and radial basis function neural networks (RBFNN). A descriptor refinement step including SOFMNN clustering analysis and correlation analysis is implemented. The SOFMNN clustering analysis is applied to classify descriptors, and the representative descriptors in the groups are selected as neural network inputs according to their closeness to the experimental values through correlation analysis. Redundant descriptors and intuitively biased choices of descriptors can be avoided by this newly introduced step. Using RBFNN calculation with the selected descriptors, chemical accuracy (≤1 kcal·mol−1) is achieved for all 92 calculated organic Y-NO homolysis BDE calculated by DFT-B3LYP, and the mean absolute deviations (MADs) of the B3LYP/6-31G(d) and B3LYP/STO-3G methods are reduced from 4.45 and 10.53 kcal·mol−1 to 0.15 and 0.18 kcal·mol−1, respectively. The improved results for the minimal basis set STO-3G reach the same accuracy as those of 6-31G(d), and thus B3LYP calculation with the minimal basis set is recommended to be used for minimizing the computational cost and to expand the applications to large molecular systems. Further extrapolation tests are performed with six molecules (two containing Si-NO bonds and two containing fluorine), and the accuracy of the tests was within 1 kcal·mol−1. This study shows that DFT-SOFM-RBFNN is an efficient and highly accurate method for Y-NO homolysis BDE. The method may be used as a tool to design new NO carrier molecules. PMID:22942689
Assessing the accuracy of predictive models for numerical data: Not r nor r2, why not? Then what?
2017-01-01
Assessing the accuracy of predictive models is critical because predictive models have been increasingly used across various disciplines and predictive accuracy determines the quality of resultant predictions. Pearson product-moment correlation coefficient (r) and the coefficient of determination (r2) are among the most widely used measures for assessing predictive models for numerical data, although they are argued to be biased, insufficient and misleading. In this study, geometrical graphs were used to illustrate what were used in the calculation of r and r2 and simulations were used to demonstrate the behaviour of r and r2 and to compare three accuracy measures under various scenarios. Relevant confusions about r and r2, has been clarified. The calculation of r and r2 is not based on the differences between the predicted and observed values. The existing error measures suffer various limitations and are unable to tell the accuracy. Variance explained by predictive models based on cross-validation (VEcv) is free of these limitations and is a reliable accuracy measure. Legates and McCabe’s efficiency (E1) is also an alternative accuracy measure. The r and r2 do not measure the accuracy and are incorrect accuracy measures. The existing error measures suffer limitations. VEcv and E1 are recommended for assessing the accuracy. The applications of these accuracy measures would encourage accuracy-improved predictive models to be developed to generate predictions for evidence-informed decision-making. PMID:28837692
Kurasawa, Shintaro; Koyama, Shouhei; Ishizawa, Hiroaki; Fujimoto, Keisaku; Chino, Shun
2017-11-23
This paper describes and verifies a non-invasive blood glucose measurement method using a fiber Bragg grating (FBG) sensor system. The FBG sensor is installed on the radial artery, and the strain (pulse wave) that is propagated from the heartbeat is measured. The measured pulse wave signal was used as a collection of feature vectors for multivariate analysis aiming to determine the blood glucose level. The time axis of the pulse wave signal was normalized by two signal processing methods: the shortest-time-cut process and 1-s-normalization process. The measurement accuracy of the calculated blood glucose level was compared with the accuracy of these signal processing methods. It was impossible to calculate a blood glucose level exceeding 200 mg/dL in the calibration curve that was constructed by the shortest-time-cut process. In the 1-s-normalization process, the measurement accuracy of the blood glucose level was improved, and a blood glucose level exceeding 200 mg/dL could be calculated. By verifying the loading vector of each calibration curve to calculate the blood glucose level with a high measurement accuracy, we found the gradient of the peak of the pulse wave at the acceleration plethysmogram greatly affected.
James, Kevin R; Dowling, David R
2008-09-01
In underwater acoustics, the accuracy of computational field predictions is commonly limited by uncertainty in environmental parameters. An approximate technique for determining the probability density function (PDF) of computed field amplitude, A, from known environmental uncertainties is presented here. The technique can be applied to several, N, uncertain parameters simultaneously, requires N+1 field calculations, and can be used with any acoustic field model. The technique implicitly assumes independent input parameters and is based on finding the optimum spatial shift between field calculations completed at two different values of each uncertain parameter. This shift information is used to convert uncertain-environmental-parameter distributions into PDF(A). The technique's accuracy is good when the shifted fields match well. Its accuracy is evaluated in range-independent underwater sound channels via an L(1) error-norm defined between approximate and numerically converged results for PDF(A). In 50-m- and 100-m-deep sound channels with 0.5% uncertainty in depth (N=1) at frequencies between 100 and 800 Hz, and for ranges from 1 to 8 km, 95% of the approximate field-amplitude distributions generated L(1) values less than 0.52 using only two field calculations. Obtaining comparable accuracy from traditional methods requires of order 10 field calculations and up to 10(N) when N>1.
Higher-Order Adaptive Finite-Element Methods for Kohn-Sham Density Functional Theory
2012-07-03
systems studied, we observe diminishing returns in computational savings beyond the sixth-order for accuracies commensurate with chemi- cal accuracy...calculations. Further, we demonstrate the capability of the proposed approach to compute the electronic structure of materials systems contain- ing a...benchmark systems studied, we observe diminishing returns in computational savings beyond the sixth-order for accuracies commensurate with chemical accuracy
Kappas, A; Drummond, G S; Munson, D P; Marshall, J R
2001-12-01
The religious convictions of parents who are Jehovah's Witness adherents lead them to reject the use of exchange transfusions as therapy for severe hyperbilirubinemia in newborns in whom intensive phototherapy has failed to control this problem. Consequently, physicians caring for such infants may be obliged to initiate legal action to compel use of the procedure when severe hyperbilirubinemia not sufficiently responsive to phototherapy warrants an exchange transfusion. Our goal was to determine if we could use the potent inhibitor of bilirubin production, Sn-Mesoporphyrin (SnMP), to resolve the troubling medical-legal issues in such situations in 2 infants with hemolytic disease of the newborn who required exchange transfusions for severe hyperbilirubinemia but whose Jehovah's Witness parents rejected the procedure. SnMP was administered in a single dose, as in previous studies, at the time when exchange transfusion would have been initiated and plasma bilirubin levels were monitored at close intervals thereafter. SnMP is a potent inhibitor of heme oxygenase, the rate-limiting enzyme in catabolism of heme to bilirubin. We found in earlier studies that in single doses of 6 micromol/kg birth weight, SnMP is extremely effective in moderating the course of hyperbilirubinemia and in eliminating the need for supplemental phototherapy in jaundiced newborns. In the 2 cases described, a single dose of SnMP (6 micromol/kg birth weight) was administered intramuscularly to severely jaundiced infants with immune hemolysis at a time when clinical circumstances dictated the need for exchange transfusion. CASE 1: This patient was a preterm male infant (gestational age: 35 5/7 weeks; birth weight: 2790 g) whose plasma bilirubin concentration (PBC) at 1 hour after birth was 5.0 mg/dL. Despite intensive phototherapy with 3 banks of lights and 1 biliblanket, the PBC increased steadily with no diminution in the rate of increase for 75 hours. In view of the problems of immune hemolysis, and prematurity, and the inability of phototherapy to stop progression of hyperbilirubinemia, a decision to carry out an exchange transfusion was made; the decision was, however, rejected by the Jehovah's Witness parents. Pending legal action to compel use of the procedure, a request to this (Rockefeller) laboratory for SnMP was made; its use was approved by the Food and Drug Administration; and the inhibitor was delivered to the physician-in-charge (D.P.M.) in Sioux Falls, South Dakota. The single dose of SnMP was administered to the infant at 75 hours after birth; the course of hyperbilirubinemia before and after the use of the inhibitor is shown in Fig 1. [figure: see text]. CASE 2: This female term infant (gestational age: 38-39 weeks; birth weight: 4140 g) with immune hemolysis was delivered by cesarean section and because of problems related to meconium aspiration required helicopter transfer to the Special Care Nursery in Abilene, Texas, where 10 hours after birth the first PBC was determined to be 18.0 mg/dL. Double-bank phototherapy plus a biliblanket was initiated; a third bank of lights was later ordered. The PBC fluctuated in the ensuing 2 days between 13.8 to 25.8 mg/dL during which suggestive clinical signs of possible bilirubin encephalopathy became manifest. In view of the clinical circumstances and the continued severe hyperbilirubinemia, permission for a double-exchange transfusion was requested. The parents, who were Jehovah's Witness adherents, refused the procedure. While preparing legal action to compel use of the exchange, a request was made to this (Rockefeller) laboratory for use of SnMP to attempt control of hyperbilirubinemia. With FDA approval, the SnMP was delivered to the attending neonatologist (J. R. M.) in Abilene and administered in a single dose (6 micromol/kg birth weight) at 56 hours after birth when the PBC was 19.5 mg/dL. The course of bilirubinemia before and after SnMP use is shown in Fig 2. [figure: see text]. The use of SnMP to moderate or prevent the development of severe hyperbilirubinemia in newborns (preterm, near-term, term with high PBCs [15-18 mg/dL], ABO-incompatibility; glucose-6-phosphate dehydrogenase deficiency) has been extensively studied in carefully conducted clinical trials the results of which have been reported earlier. This inhibitor of bilirubin production has demonstrated marked efficacy in moderating the course of hyperbilirubinemia in all diagnostic groups of unconjugated neonatal jaundice. The 2 cases described in this report confirmed the efficacy of SnMP in terminating progression of hyperbilirubinemia in infants in whom phototherapy had failed to sufficiently control the problem and whose parents, for religious reasons, would not permit exchange transfusions. Interdiction of severe hyperbilirubinemia by inhibiting the production of bilirubin with SnMP can be an effective alternative to the use of exchange transfusion in the management of severe newborn jaundice that has not responded sufficiently to light treatment to ease concern about the development of bilirubin encephalopathy.
Liu, Derek; Sloboda, Ron S
2014-05-01
Boyer and Mok proposed a fast calculation method employing the Fourier transform (FT), for which calculation time is independent of the number of seeds but seed placement is restricted to calculation grid points. Here an interpolation method is described enabling unrestricted seed placement while preserving the computational efficiency of the original method. The Iodine-125 seed dose kernel was sampled and selected values were modified to optimize interpolation accuracy for clinically relevant doses. For each seed, the kernel was shifted to the nearest grid point via convolution with a unit impulse, implemented in the Fourier domain. The remaining fractional shift was performed using a piecewise third-order Lagrange filter. Implementation of the interpolation method greatly improved FT-based dose calculation accuracy. The dose distribution was accurate to within 2% beyond 3 mm from each seed. Isodose contours were indistinguishable from explicit TG-43 calculation. Dose-volume metric errors were negligible. Computation time for the FT interpolation method was essentially the same as Boyer's method. A FT interpolation method for permanent prostate brachytherapy TG-43 dose calculation was developed which expands upon Boyer's original method and enables unrestricted seed placement. The proposed method substantially improves the clinically relevant dose accuracy with negligible additional computation cost, preserving the efficiency of the original method.
First-principles calculations of mobility
NASA Astrophysics Data System (ADS)
Krishnaswamy, Karthik
First-principles calculations can be a powerful predictive tool for studying, modeling and understanding the fundamental scattering mechanisms impacting carrier transport in materials. In the past, calculations have provided important qualitative insights, but numerical accuracy has been limited due to computational challenges. In this talk, we will discuss some of the challenges involved in calculating electron-phonon scattering and carrier mobility, and outline approaches to overcome them. Topics will include the limitations of models for electron-phonon interaction, the importance of grid sampling, and the use of Gaussian smearing to replace energy-conserving delta functions. Using prototypical examples of oxides that are of technological importance-SrTiO3, BaSnO3, Ga2O3, and WO3-we will demonstrate computational approaches to overcome these challenges and improve the accuracy. One approach that leads to a distinct improvement in the accuracy is the use of analytic functions for the band dispersion, which allows for an exact solution of the energy-conserving delta function. For select cases, we also discuss direct quantitative comparisons with experimental results. The computational approaches and methodologies discussed in the talk are general and applicable to other materials, and greatly improve the numerical accuracy of the calculated transport properties, such as carrier mobility, conductivity and Seebeck coefficient. This work was performed in collaboration with B. Himmetoglu, Y. Kang, W. Wang, A. Janotti and C. G. Van de Walle, and supported by the LEAST Center, the ONR EXEDE MURI, and NSF.
Self-consistent-field KKR-CPA calculations in the atomic-sphere approximations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Singh, P.P. Gonis, A.; de Fontaine, D.
1991-12-03
We present a formulation of the Korringa-Kohn-Rostoker coherent potential approximation (KKR-CPA) for the treatment of substitutionally disordered alloys within the KKR atomic-sphere approximations (ASA). This KKR-ASA-CPA represents the first step toward the implementation of a full cell potential CPA, and combines the accuracy of the KKR-CPA method with the flexibility of treating complex crystal structures. The accuracy of this approach has been tested by comparing the self-consistent-field (SCF) KKR-ASA-CPA calculations of Cu-Pd alloys with experimental results and previous SCF-KKR-CPA calculations.
Interrelated Dimensional Chains in Predicting Accuracy of Turbine Wheel Assembly Parameters
NASA Astrophysics Data System (ADS)
Yanyukina, M. V.; Bolotov, M. A.; Ruzanov, N. V.
2018-03-01
The working capacity of any device primarily depends on the assembly accuracy which, in its turn, is determined by the quality of each part manufactured, i.e., the degree of conformity between final geometrical parameters and the set ones. However, the assembly accuracy depends not only on a qualitative manufacturing process but also on the assembly process correctness. In this connection, there were preliminary calculations of assembly stages in terms of conformity to real geometrical parameters with their permissible values. This task is performed by means of the calculation of dimensional chains. The calculation of interrelated dimensional chains in the aircraft industry requires particular attention. The article considers the issues of dimensional chain calculation modelling by the example of the turbine wheel assembly process. The authors described the solution algorithm in terms of mathematical statistics implemented in Matlab. The paper demonstrated the results of a dimensional chain calculation for a turbine wheel in relation to the draw of turbine blades to the shroud ring diameter. Besides, the article provides the information on the influence of a geometrical parameter tolerance for the dimensional chain link elements on a closing one.
NASA Astrophysics Data System (ADS)
Kamata, S.
2017-12-01
Solid-state thermal convection plays a major role in the thermal evolution of solid planetary bodies. Solving the equation system for thermal evolution considering convection requires 2-D or 3-D modeling, resulting in large calculation costs. A 1-D calculation scheme based on mixing length theory (MLT) requires a much lower calculation cost and is suitable for parameter studies. A major concern for the MLT scheme is its accuracy due to a lack of detailed comparisons with higher dimensional schemes. In this study, I quantify its accuracy via comparisons of thermal profiles obtained by 1-D MLT and 3-D numerical schemes. To improve the accuracy, I propose a new definition of the mixing length (l), which is a parameter controlling the efficiency of heat transportation due to convection. Adopting this new definition of l, I investigate the thermal evolution of Dione and Enceladus under a wide variety of parameter conditions. Calculation results indicate that each satellite requires several tens of GW of heat to possess a 30-km-thick global subsurface ocean. Dynamical tides may be able to account for such an amount of heat, though their ices need to be highly viscous.
Dissociation between exact and approximate addition in developmental dyslexia.
Yang, Xiujie; Meng, Xiangzhi
2016-09-01
Previous research has suggested that number sense and language are involved in number representation and calculation, in which number sense supports approximate arithmetic, and language permits exact enumeration and calculation. Meanwhile, individuals with dyslexia have a core deficit in phonological processing. Based on these findings, we thus hypothesized that children with dyslexia may exhibit exact calculation impairment while doing mental arithmetic. The reaction time and accuracy while doing exact and approximate addition with symbolic Arabic digits and non-symbolic visual arrays of dots were compared between typically developing children and children with dyslexia. Reaction time analyses did not reveal any differences across two groups of children, the accuracies, interestingly, revealed a distinction of approximation and exact addition across two groups of children. Specifically, two groups of children had no differences in approximation. Children with dyslexia, however, had significantly lower accuracy in exact addition in both symbolic and non-symbolic tasks than that of typically developing children. Moreover, linguistic performances were selectively associated with exact calculation across individuals. These results suggested that children with dyslexia have a mental arithmetic deficit specifically in the realm of exact calculation, while their approximation ability is relatively intact. Copyright © 2016 Elsevier Ltd. All rights reserved.
High-precision positioning system of four-quadrant detector based on the database query
NASA Astrophysics Data System (ADS)
Zhang, Xin; Deng, Xiao-guo; Su, Xiu-qin; Zheng, Xiao-qiang
2015-02-01
The fine pointing mechanism of the Acquisition, Pointing and Tracking (APT) system in free space laser communication usually use four-quadrant detector (QD) to point and track the laser beam accurately. The positioning precision of QD is one of the key factors of the pointing accuracy to APT system. A positioning system is designed based on FPGA and DSP in this paper, which can realize the sampling of AD, the positioning algorithm and the control of the fast swing mirror. We analyze the positioning error of facular center calculated by universal algorithm when the facular energy obeys Gauss distribution from the working principle of QD. A database is built by calculation and simulation with MatLab software, in which the facular center calculated by universal algorithm is corresponded with the facular center of Gaussian beam, and the database is stored in two pieces of E2PROM as the external memory of DSP. The facular center of Gaussian beam is inquiry in the database on the basis of the facular center calculated by universal algorithm in DSP. The experiment results show that the positioning accuracy of the high-precision positioning system is much better than the positioning accuracy calculated by universal algorithm.
Glassman, Tavis; Braun, Robert E; Dodd, Virginia; Miller, Jeffrey M; Miller, E Maureen
2010-04-01
This study assessed the extent to which the Theory of Planned Behavior (TPB) correctly predicted college student's motivation to consume alcohol on game day based on alcohol consumption rates. Three cohorts of 1,000 participants each (N = 3,000) were randomly selected and invited to complete an anonymous web-based survey the Monday following one of three designated college home football games. Path analyses were conducted to determine which of the TPB constructs were most effective in predicting Behavioral Intention and alcohol consumption among social, high-risk, and extreme drinkers. Social drinkers, high-risk, and those drinkers who engage in Extreme Ritualistic Alcohol Consumption (ERAC) were defined as males who consumed 1-4, 5-9, or 10 or more drinks on game day (1-3, 4-8, or nine or more drinks for females), respectively. Attitude Towards the Behavior and Subjective Norm constructs predicted participant's intentions to consume alcohol and corresponding behavior among all three classifications of drinkers; whereas the Perceived Behavioral Control (PBC) construct inconsistently predicted intention and alcohol consumption. Based on Behavioral Intention, the proportion of variance the TPB model explained decreased as participants alcohol consumption increased. It appears that the TPB constructs Attitude Toward the Behavior and Subjective Norm can effectively be utilized when designing universal prevention interventions targeting game day alcohol consumption among college students. However, the applicability of the PBC construct remains in question. While select constructs in the TPB appear to have predictive ability, the usefulness of the complete theoretical framework is limited when trying to predict high-risk drinking and ERAC. These findings suggest that other behavioral theories should be considered when addressing the needs of high-risk and extreme drinkers.
Autoimmune liver serology: current diagnostic and clinical challenges.
Bogdanos, Dimitrios-P; Invernizzi, Pietro; Mackay, Ian-R; Vergani, Diego
2008-06-07
Liver-related autoantibodies are crucial for the correct diagnosis and classification of autoimmune liver diseases (AiLD), namely autoimmune hepatitis types 1 and 2 (AIH-1 and 2), primary biliary cirrhosis (PBC), and the sclerosing cholangitis variants in adults and children. AIH-1 is specified by anti-nuclear antibody (ANA) and smooth muscle antibody (SMA). AIH-2 is specified by antibody to liver kidney microsomal antigen type-1 (anti-LKM1) and anti-liver cytosol type 1 (anti-LC1). SMA, ANA and anti-LKM antibodies can be present in de-novo AIH following liver transplantation. PBC is specified by antimitochondrial antibodies (AMA) reacting with enzymes of the 2-oxo-acid dehydrogenase complexes (chiefly pyruvate dehydrogenase complex E2 subunit) and disease-specific ANA mainly reacting with nuclear pore gp210 and nuclear body sp100. Sclerosing cholangitis presents as at least two variants, first the classical primary sclerosing cholangitis (PSC) mostly affecting adult men wherein the only (and non-specific) reactivity is an atypical perinuclear antineutrophil cytoplasmic antibody (p-ANCA), also termed perinuclear anti-neutrophil nuclear antibodies (p-ANNA) and second the childhood disease called autoimmune sclerosing cholangitis (ASC) with serological features resembling those of type 1 AIH. Liver diagnostic serology is a fast-expanding area of investigation as new purified and recombinant autoantigens, and automated technologies such as ELISAs and bead assays, become available to complement (or even compete with) traditional immunofluorescence procedures. We survey for the first time global trends in quality assurance impacting as it does on (1) manufacturers/purveyors of kits and reagents, (2) diagnostic service laboratories that fulfill clinicians' requirements, and (3) the end-user, the physician providing patient care, who must properly interpret test results in the overall clinical context.
Autoimmune liver serology: Current diagnostic and clinical challenges
Bogdanos, Dimitrios P; Invernizzi, Pietro; Mackay, Ian R; Vergani, Diego
2008-01-01
Liver-related autoantibodies are crucial for the correct diagnosis and classification of autoimmune liver diseases (AiLD), namely autoimmune hepatitis types 1 and 2 (AIH-1 and 2), primary biliary cirrhosis (PBC), and the sclerosing cholangitis variants in adults and children. AIH-1 is specified by anti-nuclear antibody (ANA) and smooth muscle antibody (SMA). AIH-2 is specified by antibody to liver kidney microsomal antigen type-1 (anti-LKM1) and anti-liver cytosol type 1 (anti-LC1). SMA, ANA and anti-LKM antibodies can be present in de-novo AIH following liver transplantation. PBC is specified by antimitochondrial antibodies (AMA) reacting with enzymes of the 2-oxo-acid dehydrogenase complexes (chiefly pyruvate dehydrogenase complex E2 subunit) and disease-specific ANA mainly reacting with nuclear pore gp210 and nuclear body sp100. Sclerosing cholangitis presents as at least two variants, first the classical primary sclerosing cholangitis (PSC) mostly affecting adult men wherein the only (and non-specific) reactivity is an atypical perinuclear antineutrophil cytoplasmic antibody (p-ANCA), also termed perinuclear anti-neutrophil nuclear antibodies (p-ANNA) and second the childhood disease called autoimmune sclerosing cholangitis (ASC) with serological features resembling those of type 1 AIH. Liver diagnostic serology is a fast-expanding area of investigation as new purified and recombinant autoantigens, and automated technologies such as ELISAs and bead assays, become available to complement (or even compete with) traditional immunofluorescence procedures. We survey for the first time global trends in quality assurance impacting as it does on (1) manufacturers/purveyors of kits and reagents, (2) diagnostic service laboratories that fulfill clinicians’ requirements, and (3) the end-user, the physician providing patient care, who must properly interpret test results in the overall clinical context. PMID:18528935
Edwards, Jeffrey E; Eliot, Lise; Parkinson, Andrew; Karan, Sharon; MacConell, Leigh
2017-09-01
Obeticholic acid (OCA), a potent and selective farnesoid X receptor agonist, is indicated for the treatment of primary biliary cholangitis (PBC). We investigated the potential drug-drug interaction effect of OCA on metabolic CYP450 enzymes and drug transporters. Five phase 1 single-center, open-label, fixed-sequence, inpatient studies were conducted in healthy adult subjects to evaluate the effect of oral daily doses of 10 or 25 mg OCA on single-dose plasma pharmacokinetics of specific probe substrates for enzymes CYP1A2 (caffeine, R-warfarin), CYP3A (midazolam, R-warfarin), CYP2C9 (S-warfarin), CYP2D6 (dextromethorphan), CYP2C19 (omeprazole), and drug transporters, BCRP/OATP1B1/OATP1B3 (rosuvastatin), and P-gp (digoxin). OCA showed no substantial suppression/inhibition of S-warfarin, digoxin, and dextromethorphan and weak interactions with caffeine, omeprazole, rosuvastatin, and midazolam. The maximal pharmacodynamic responses (E max ) to warfarin-based INR, PT, and aPTT were reduced by 11%, 11%, and 1%, respectively, for the 10-mg dose group and by 7%, 7% and 0%, respectively, for the 25-mg dose group. Overall, drugs dosed in combination with OCA were well tolerated, and most adverse events were mild in severity. No clinically important trends were noted in laboratory evaluations, vital signs, or 12-lead ECGs. In these studies, OCA showed weak to no suppression/inhibition of metabolic enzymes and drug transporters at the highest recommended therapeutic dose in patients with PBC. On the basis on these analyses, monitoring and maintenance of target INR range are required during coadministration of OCA with drugs that are metabolized by CYP1A2 (R-warfarin). Intercept Pharmaceuticals, Inc.
Emam, Hany; Beheiri, Galal; Elsalanty, Mohammed; Sharawy, Mohamed
2011-01-01
Anorganic bovine hydroxyapatite matrix (ABM), when coupled with synthetic cell-binding peptide (P15), mimics the cell-binding region of type 1 collagen and is commercially available suspended in a sodium hyaluronate carrier. The aim of the present study, therefore, was to test the efficacy of ABM/P-15 Putty (DENTSPLY Friadent CeraMed) as a sole graft material for sinus augmentation in patients with severely resorbed posterior maxillae. Sinus augmentation was performed in 10 patients using ABM/P-15 Putty and two provisional dental implants (3.0 mm in diameter). The graft and implants were placed simultaneously with the aid of a surgical stent. After 8 or 16 weeks, the implants were removed using a 4.25-mm trephine bur; this was followed by immediate placement of wider-diameter (5.5-mm) implants. All 20 implants were scanned by microcomputed tomography to determine bone mineral density (BMD), percent bone volume (PBV), and percent bone contact (PBC). There was a significant increase in the BMD of bone around the implants at 8 weeks and 16 weeks compared to native residual (control) bone. There was no significant difference in PBV or PBC between 8 weeks and 16 weeks. The average increase in bone height at 16 weeks was 9.63 ± 1 mm. Microcomputed tomographic images and histologic sections showed dense graft particles surrounded by vital trabecular bone. BMD increases as early as 8 weeks and does not show an additional increase after 16 weeks. PepGen P-15 Putty was found to be a promising osteoconductive graft for sinus augmentation, supporting immediate placement of implants.
Evaluating the ParticipACTION "Think Again" Campaign.
Gainforth, Heather L; Jarvis, Jocelyn W; Berry, Tanya R; Chulak-Bozzer, Tala; Deshpande, Sameer; Faulkner, Guy; Rhodes, Ryan E; Spence, John C; Tremblay, Mark S; Latimer-Cheung, Amy E
2016-08-01
Introduction ParticipACTION's 2011 "Think Again" campaign aimed to draw parents', and specifically mothers', attention to the amount of physical activity (PA) their children do relative to the national guidelines (physical activity guidelines [PAG]). Purpose To evaluate ParticipACTION's "Think Again" campaign in the context of the hierarchy of effects model. Methods Data were drawn from "Think Again" campaign evaluations conducted among two cohorts of parents with children ages 5 to 11 years (3 months postcampaign launch [T1], n = 702; 15 months postlaunch [T2], n = 670). Results At T2, campaign awareness was weakly associated with parents agreeing that their children were not active enough (p = .01, d = .18). Parents who were aware of the campaign showed greater knowledge of PAG (ps < .01, ϕs > .14), had higher outcome expectations about their children engaging in PA (p < .01, d = .16), had stronger intentions to help their child meet the guidelines (p < .01, d = .18), and engaged in more parental support behaviors (p < .001, d = .31) as compared with parents who were not aware. At T1, parents aware of the campaign had greater perceived behavioral control (PBC) to influence their child's PA participation (p < .01, d = .22), whereas parents not aware of the campaign had greater PBC to find practical ways to help their child be active (p < .01, d = .26). Parental awareness of the campaign was not associated with children meeting the PAG at either time point (ps > .05). Conclusions The campaign appeared marginally effective for increasing parental knowledge of PAG and for creating realistic awareness of children's PA levels. Additional intervention strategies are needed to produce larger effects and to change parental behavior. © 2015 Society for Public Health Education.
Ando, Yugo; Yang, Guo-Xiang; Kenny, Thomas P; Kawata, Kazuhito; Zhang, Weici; Huang, Wenting; Leung, Patrick S C; Lian, Zhe-Xiong; Okazaki, Kazuichi; Ansari, Aftab A; He, Xiao-Song; Invernizzi, Pietro; Ridgway, William M; Lu, Qianjin; Gershwin, M Eric
2013-03-01
Dominant-negative TGF-β receptor II (dnTGF-βRII) mice spontaneously develop an autoimmune cholangitis resembling human primary biliary cirrhosis (PBC). Interestingly, the dominant-negative TGF-β receptor is expressed by both CD4(+) and CD8(+) T cells and leads to greatly reduced (but not absent) TGF-β signaling resulting in T cell intrinsic cell mediated autoimmunity. However, the mechanisms of the T cell dysregulation remain unclear. Recently it has been shown that TGF-β signaling is intimately involved with miRNA biogenesis and control. Herein we show that lack of T cell TGF-β signaling leads to down regulation of T cell miRNAs but up-regulation of the key inflammatory miRNA 21. Furthermore, the expression of miR-21 from hepatic effector CD8(+) T cells is significantly higher than in the same subsets isolated from spleen and mesenteric lymph nodes of the dnTGF-βRII mice. Previous studies indicate that miR-21 increases the synthesis of IFN-γ and IL-17A by T cells and suppresses apoptosis via programmed cell death protein 4 (PDCD4). Data presented herein demonstrate that transfecting w.t. B6 T cell subsets with miR-21 resulted in up-regulation of the inflammatory cytokines TNF-α and IFN-γ, thus partly replicating the dnTGF-βRII T cell phenotype. In conclusion, these data suggest miR-21 plays a critical role in the production of pro-inflammatory cytokines in dnTGF-βRII mice, which could be a contributing factor for the development of the organ-specific autoimmune cholangitis and colitis in this murine model of human PBC. Copyright © 2013 Elsevier Ltd. All rights reserved.
Ma, Teng; Tao, Jingli; Yang, Minghui; He, Changjiu; Tian, Xiuzhi; Zhang, Xiaosheng; Zhang, Jinlong; Deng, Shoulong; Feng, Jianzhong; Zhang, Zhenzhen; Wang, Jing; Ji, Pengyun; Song, Yukun; He, Pingli; Han, Hongbing; Fu, Juncai; Lian, Zhengxing; Liu, Guoshi
2017-08-01
Melatonin as a potent antioxidant exhibits important nutritional and medicinal values. To produce melatonin-enriched milk will benefit the consumers. In this study, a sheep bioreactor which generates melatonin-enriched milk has been successfully developed by the technology that combined CRISPR/Cas9 system and microinjection. The AANAT and ASMT were cloned from pineal gland of Dorper sheep (Ovis aries). The in vitro studies found that AANAT and ASMT were successfully transferred to the mammary epithelial cell lines and significantly increased melatonin production in the culture medium compared to the nontransgenic cell lines. In addition, the Cas9 mRNA, sgRNA, and the linearized vectors pBC1-AANAT and pBC1-ASMT were co-injected into the cytoplasm of pronuclear embryos which were implanted into ewes by oviducts transferring. Thirty-four transgenic sheep were generated with the transgenic positive rate being roughly 35% which were identified by Southern blot and sequencing. Seven carried transgenic AANAT, two carried ASMT, and 25 carried both of AANAT and ASMT genes. RT-PCR and Western blot demonstrated that the lambs expressed these genes in their mammary epithelial cells and these animals produced melatonin-enriched milk. This is the first report to show a functional AANAT and ASMT transgenic animal model which produce significantly high levels of melatonin milk compared to their wild-type counterparts. The advanced technologies used in the study laid a foundation for generating large transgenic livestock, for example, the cows, which can produce high level of melatonin milk. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Liu, Ke; Kurien, Biji T.; Zimmerman, Sarah L.; Kaufman, Kenneth M.; Taft, Diana H.; Kottyan, Leah C.; Lazaro, Sara; Weaver, Carrie A.; Ice, John A.; Adler, Adam J.; Chodosh, James; Radfar, Lida; Rasmussen, Astrid; Stone, Donald U.; Lewis, David M.; Li, Shibo; Koelsch, Kristi A.; Igoe, Ann; Talsania, Mitali; Kumar, Jay; Maier-Moore, Jacen S.; Harris, Valerie M.; Gopalakrishnan, Rajaram; Jonsson, Roland; Lessard, James A.; Lu, Xianglan; Gottenberg, Jacques-Eric; Anaya, Juan-Manuel; Cunninghame-Graham, Deborah S.; Huang, Andrew J. W.; Brennan, Michael T.; Hughes, Pamela; Illei, Gabor G.; Miceli-Richard, Corinne; Keystone, Edward C.; Bykerk, Vivian P.; Hirschfield, Gideon; Xie, Gang; Ng, Wan-Fai; Nordmark, Gunnel; Eriksson, Per; Omdal, Roald; Rhodus, Nelson L.; Rischmueller, Maureen; Rohrer, Michael; Segal, Barbara M.; Vyse, Timothy J.; Wahren-Herlenius, Marie; Witte, Torsten; Pons-Estel, Bernardo; Alarcon-Riquelme, Marta E.; Guthridge, Joel M.; James, Judith A.; Lessard, Christopher J.; Kelly, Jennifer A.; Thompson, Susan D.; Gaffney, Patrick M.; Montgomery, Courtney G.; Edberg, Jeffrey C; Kimberly, Robert P; Alarcón, Graciela S.; Langefeld, Carl L.; Gilkeson, Gary S.; Kamen, Diane L.; Tsao, Betty P.; McCune, W. Joseph; Salmon, Jane E.; Merrill, Joan T.; Weisman, Michael H; Wallace, Daniel J; Utset, Tammy O; Bottinger, Erwin P.; Amos, Christopher I.; Siminovitch, Katherine A.; Mariette, Xavier; Sivils, Kathy L.
2016-01-01
Objective More than 80% of autoimmune disease is female dominant, but the mechanism for this female bias is poorly understood. We suspected an X chromosome dose effect and hypothesized that trisomy X (47,XXX , 1 in ~1,000 live female births) would be increased in female predominant diseases (e.g. systemic lupus erythematosus [SLE], primary Sjögren’s syndrome [SS], primary biliary cirrhosis [PBC] and rheumatoid arthritis [RA]) compared to diseases without female predominance (sarcoidosis) and controls. Methods We identified 47,XXX subjects using aggregate data from single nucleotide polymorphism (SNP) arrays and confirmed, when possible, by fluorescent in situ hybridization (FISH) or quantitative polymerase chain reaction (q-PCR). Results We found 47,XXX in seven of 2,826 SLE and three of 1,033 SS female patients, but only in two of the 7,074 female controls (p=0.003, OR=8.78, 95% CI: 1.67-86.79 and p=0.02, OR=10.29, 95% CI: 1.18-123.47; respectively). One 47,XXX subject was present for ~404 SLE women and ~344 SS women. 47,XXX was present in excess among SLE and SS subjects. Conclusion The estimated prevalence of SLE and SS in women with 47,XXX was respectively ~2.5 and ~2.9 times higher than in 46,XX women and ~25 and ~41 times higher than in 46,XY men. No statistically significant increase of 47,XXX was observed in other female-biased diseases (PBC or RA), supporting the idea of multiple pathways to sex bias in autoimmunity. PMID:26713507
Natural killer cells regulate T cell immune responses in primary biliary cirrhosis.
Shimoda, Shinji; Hisamoto, Satomi; Harada, Kenichi; Iwasaka, Sho; Chong, Yong; Nakamura, Minoru; Bekki, Yuki; Yoshizumi, Tomoharu; Shirabe, Ken; Ikegami, Toru; Maehara, Yoshihiko; He, Xiao-Song; Gershwin, M Eric; Akashi, Koichi
2015-12-01
The hallmark of primary biliary cirrhosis (PBC) is the presence of autoreactive T- and B-cell responses that target biliary epithelial cells (BECs). Biliary cell cytotoxicity is dependent upon initiation of innate immune responses followed by chronic adaptive, as well as bystander, mechanisms. Critical to these mechanisms are interactions between natural killer (NK) cells and BECs. We have taken advantage of the ability to isolate relatively pure viable preparations of liver-derived NK cells, BECs, and endothelial cells, and studied interactions between NK cells and BECs and focused on the mechanisms that activate autoreactive T cells, their dependence on interferon (IFN)-γ, and expression of BEC major histocompatibility complex (MHC) class I and II molecules. Here we show that at a high NK/BEC ratio, NK cells are cytotoxic for autologous BECs, but are not dependent on autoantigen, yet still activate autoreactive CD4(+) T cells in the presence of antigen presenting cells. In contrast, at a low NK/BEC ratio, BECs are not lysed, but IFN-γ production is induced, which facilitates expression of MHC class I and II molecules on BEC and protects them from lysis upon subsequent exposure to autoreactive NK cells. Furthermore, IFN-γ secreted from NK cells after exposure to autologous BECs is essential for this protective function and enables autoreactive CD4(+) T cells to become cytopathic. NK cell-mediated innate immune responses are likely critical at the initial stage of PBC, but also facilitate and maintain the chronic cytopathic effect of autoantigen-specific T cells, essential for progression of disease. © 2015 by the American Association for the Study of Liver Diseases.
Barkoukis, Vassilis; Hagger, Martin S; Lambropoulos, George; Tsorbatzoudis, Haralambos
2010-12-01
The trans-contextual model (TCM) is an integrated model of motivation that aims to explain the processes by which agentic support for autonomous motivation in physical education promotes autonomous motivation and physical activity in a leisure-time context. It is proposed that perceived support for autonomous motivation in physical education is related to autonomous motivation in physical education and leisure-time contexts. Furthermore, relations between autonomous motivation and the immediate antecedents of intentions to engage in physical activity behaviour and actual behaviour are hypothesized. The purpose of the present study was to incorporate the constructs of basic psychological need satisfaction in the TCM to provide a more comprehensive explanation of motivation and demonstrate the robustness of the findings of previous tests of the model that have not incorporated these constructs. Students (N=274) from Greek secondary schools. Participants completed self-report measures of perceived autonomy support, autonomous motivation, and basic psychological need satisfaction in physical education. Follow-up measures of these variables were taken in a leisure-time context along with measures of attitudes, subjective norms, perceived behavioural control (PBC), and intentions from the theory of planned behaviour 1 week later. Self-reported physical activity behaviour was measured 4 weeks later. Results supported TCM hypotheses. Basic psychological need satisfaction variables uniquely predicted autonomous motivation in physical education and leisure time as well as the antecedents of intention, namely, attitudes, and PBC. The basic psychological need satisfaction variables also mediated the effects of perceived autonomy support on autonomous motivation in physical education. Findings support the TCM and provide further information of the mechanisms in the model and integrated theories of motivation in physical education and leisure time.
The Pathogenesis of Autoimmune Liver Disease.
Arndtz, Katherine; Hirschfield, Gideon M
Autoimmune liver disease (AILD) encompasses 3 main distinct clinical diseases: autoimmune hepatitis, primary biliary cholangitis (formally known as cirrhosis, PBC) and primary sclerosing cholangitis (PSC). These conditions are an important, yet under-appreciated cause of patient morbidity and mortality with ongoing unmet needs for further research and clinical advances. There is observational evidence for genetic predisposition, with all 3 conditions being more common in first degree relatives. AILD is associated with the presence of auto-antibodies and higher risks of other non-hepatic auto-immune conditions. Genetic risk association studies have identified HLA and non-HLA risk loci for the development of disease, with some HLA loci providing prognostic information. This re-enforces the concept that genetic predisposition to autoimmunity is important, likely in the context of environmental exposures. Such environmental triggers are unclear but relevant risks include smoking, drug and xenobiotic exposure as well as the complexities of the microbiome. There is evidence for a loss of immune tolerance to self-antigens playing a part in the development of these conditions. In particular the IL-2 and IL-12 regulatory pathways have been implicated in pre-disposing to an unopposed inflammatory response within the liver. Main immunological themes revolve around loss of immune tolerance leading to T-cell mediated injury, imbalance in the regulation of immune cells and defective immune response to foreign antigens. For PBC and PSC, there is then the added complexity of the consequences of cholestasis on hepato-biliary injury, immune regulation and liver fibrosis. Whilst specific disease causes and triggers are still lacking, AILD arises on the background of collective genetic and environmental risk, leading to chronic and abnormal hepato-biliary immune responses. Effective and more rational therapy will ultimately be developed when the multiple pathways to liver injury are better understood. © 2016 S. Karger AG, Basel.
Optical Studies of 15 Hard X-Ray Selected Cataclysmic Binaries
NASA Astrophysics Data System (ADS)
Halpern, Jules P.; Thorstensen, John R.; Cho, Patricia; Collver, Gabriel; Motsoaledi, Mokhine; Breytenbach, Hannes; Buckley, David A. H.; Woudt, Patrick A.
2018-06-01
We conducted time-resolved optical spectroscopy and/or time-series photometry of 15 cataclysmic binaries that were discovered in hard X-ray surveys by the Swift Burst Alert Telescope and the International Gamma-Ray Astrophysics Laboratory, with the goal of measuring their orbital periods and searching for spin periods. Four of the objects in this study are new optical identifications: Swift J0535.2+2830, Swift J2006.4+3645, IGR J21095+4322, and Swift J2116.5+5336. Coherent pulsations are detected from three objects for the first time, Swift J0535.2+2830 (1523 s), 2PBC J1911.4+1412 (747 s), and 1SWXRT J230642.7+550817 (464 s), indicating that they are intermediate polars (IPs). We find two new eclipsing systems in time-series photometry: 2PBC J0658.0‑1746, a polar with a period of 2.38 hr, and Swift J2116.5+5336, a disk system that has an eclipse period of 6.56 hr. Exact or approximate spectroscopic orbital periods are found for six additional targets. Of note is the long 4.637-day orbit for Swift J0623.9‑0939, which is revealed by the radial velocities of the photospheric absorption lines of the secondary star. We also discover a 12.76 hr orbital period for RX J2015.6+3711, which confirms that the previously detected 2.00 hr X-ray period from this star is the spin period of an IP, as inferred by Coti Zelati et al. These results support the conclusion that hard X-ray selection favors magnetic CVs, with IPs outnumbering polars.
Noh, Seongmin; Kim, Miri; Park, Chang Ook; Hann, Seung-Kyung
2013-01-01
Background Vitiligo and atopic dermatitis (AD) are common dermatological disorders which may cause significant psychological and social distress leading to impaired quality of life (QoL) in patients. Objective We evaluated the degree of psychological stress and impairment of QoL in vitiligo patients as compared with AD patients and normal controls (NCs). Methods A total of 60 patients from each group and 60 NCs were enrolled. Five questionnaires on depression (Beck depression inventory, BDI), state anxiety (SA) and trait anxiety (TA), interaction anxiousness (IAS), private body consciousness (PBC) and dermatologic QoL were used. Results The vitiligo patients had a significantly higher level of TA (p<0.01), PBC (p<0.001) and impaired QoL (p<0.001) than NCs, but not BDI, SA and IAS. The AD patients had significantly higher scores for all five questionnaire items compared with NCs. In the comparison between the AD and vitiligo groups, all of the indexes except body consciousness were higher in AD patients than in vitiligo patients: BDI (p<0.01), SA (p<0.05), TA (p<0.001), IAS (p<0.01) and impaired QoL (p<0.001). Exposure of vitiligo lesions was not a significant variable in the analysis of the contribution of clinical variables of vitiligo on psychological stress and QoL. Conclusion Vitiligo, which is not accompanied by any symptoms, involves less psychological impact than AD, which is accompanied by itching. Compared to NCs, however, the elevated general anxiety and body consciousness in patients with vitiligo suggests that they may be more concerned with the aggravation of hypopigmented patches than difficulties in social interactions. PMID:24371393
The Accuracy Of Fuzzy Sugeno Method With Antropometry On Determination Natural Patient Status
NASA Astrophysics Data System (ADS)
Syahputra, Dinur; Tulus; Sawaluddin
2017-12-01
Anthropometry is one of the processes that can be used to assess nutritional status. In general anthropometry is defined as body size in terms of nutrition, then anthropometry is reviewed from various age levels and nutritional levels. Nutritional status is a description of the balance between nutritional intake with the needs of the body individually. Fuzzy logic is a logic that has a vagueness between right and wrong or between 0 and 1. Sugeno method is used because in the process of calculating nutritional status so far is still done by anthropometry. Currently information technology is growing in any aspect, one of them in the aspect of calculation with data taken from anthropometry. In this case the calculation can use the Fuzzy Sugeno Method, in order to know the great accuracy obtained. Then the results obtained using fuzzy sugeno integrated with anthropometry has an accuracy of 81.48%.
A simplified analytical random walk model for proton dose calculation
NASA Astrophysics Data System (ADS)
Yao, Weiguang; Merchant, Thomas E.; Farr, Jonathan B.
2016-10-01
We propose an analytical random walk model for proton dose calculation in a laterally homogeneous medium. A formula for the spatial fluence distribution of primary protons is derived. The variance of the spatial distribution is in the form of a distance-squared law of the angular distribution. To improve the accuracy of dose calculation in the Bragg peak region, the energy spectrum of the protons is used. The accuracy is validated against Monte Carlo simulation in water phantoms with either air gaps or a slab of bone inserted. The algorithm accurately reflects the dose dependence on the depth of the bone and can deal with small-field dosimetry. We further applied the algorithm to patients’ cases in the highly heterogeneous head and pelvis sites and used a gamma test to show the reasonable accuracy of the algorithm in these sites. Our algorithm is fast for clinical use.
Novel robust skylight compass method based on full-sky polarization imaging under harsh conditions.
Tang, Jun; Zhang, Nan; Li, Dalin; Wang, Fei; Zhang, Binzhen; Wang, Chenguang; Shen, Chong; Ren, Jianbin; Xue, Chenyang; Liu, Jun
2016-07-11
A novel method based on Pulse Coupled Neural Network(PCNN) algorithm for the highly accurate and robust compass information calculation from the polarized skylight imaging is proposed,which showed good accuracy and reliability especially under cloudy weather,surrounding shielding and moon light. The degree of polarization (DOP) combined with the angle of polarization (AOP), calculated from the full sky polarization image, were used for the compass information caculation. Due to the high sensitivity to the environments, DOP was used to judge the destruction of polarized information using the PCNN algorithm. Only areas with high accuracy of AOP were kept after the DOP PCNN filtering, thereby greatly increasing the compass accuracy and robustness. From the experimental results, it was shown that the compass accuracy was 0.1805° under clear weather. This method was also proven to be applicable under conditions of shielding by clouds, trees and buildings, with a compass accuracy better than 1°. With weak polarization information sources, such as moonlight, this method was shown experimentally to have an accuracy of 0.878°.
Jeff Jenness; J. Judson Wynne
2005-01-01
In the field of spatially explicit modeling, well-developed accuracy assessment methodologies are often poorly applied. Deriving model accuracy metrics have been possible for decades, but these calculations were made by hand or with the use of a spreadsheet application. Accuracy assessments may be useful for: (1) ascertaining the quality of a model; (2) improving model...
Wang, Hubiao; Wu, Lin; Chai, Hua; Xiao, Yaofei; Hsu, Houtse; Wang, Yong
2017-08-10
The variation of a marine gravity anomaly reference map is one of the important factors that affect the location accuracy of INS/Gravity integrated navigation systems in underwater navigation. In this study, based on marine gravity anomaly reference maps, new characteristic parameters of the gravity anomaly were constructed. Those characteristic values were calculated for 13 zones (105°-145° E, 0°-40° N) in the Western Pacific area, and simulation experiments of gravity matching-aided navigation were run. The influence of gravity variations on the accuracy of gravity matching-aided navigation was analyzed, and location accuracy of gravity matching in different zones was determined. Studies indicate that the new parameters may better characterize the marine gravity anomaly. Given the precision of current gravimeters and the resolution and accuracy of reference maps, the location accuracy of gravity matching in China's Western Pacific area is ~1.0-4.0 nautical miles (n miles). In particular, accuracy in regions around the South China Sea and Sulu Sea was the highest, better than 1.5 n miles. The gravity characteristic parameters identified herein and characteristic values calculated in various zones provide a reference for the selection of navigation area and planning of sailing routes under conditions requiring certain navigational accuracy.
Wang, Hubiao; Chai, Hua; Xiao, Yaofei; Hsu, Houtse; Wang, Yong
2017-01-01
The variation of a marine gravity anomaly reference map is one of the important factors that affect the location accuracy of INS/Gravity integrated navigation systems in underwater navigation. In this study, based on marine gravity anomaly reference maps, new characteristic parameters of the gravity anomaly were constructed. Those characteristic values were calculated for 13 zones (105°–145° E, 0°–40° N) in the Western Pacific area, and simulation experiments of gravity matching-aided navigation were run. The influence of gravity variations on the accuracy of gravity matching-aided navigation was analyzed, and location accuracy of gravity matching in different zones was determined. Studies indicate that the new parameters may better characterize the marine gravity anomaly. Given the precision of current gravimeters and the resolution and accuracy of reference maps, the location accuracy of gravity matching in China’s Western Pacific area is ~1.0–4.0 nautical miles (n miles). In particular, accuracy in regions around the South China Sea and Sulu Sea was the highest, better than 1.5 n miles. The gravity characteristic parameters identified herein and characteristic values calculated in various zones provide a reference for the selection of navigation area and planning of sailing routes under conditions requiring certain navigational accuracy. PMID:28796158
DOE Office of Scientific and Technical Information (OSTI.GOV)
Biplab, S; Soumya, R; Paul, S
2014-06-01
Purpose: For the first time in the world, BrainLAB has integrated its iPlan treatment planning system for clinical use with Elekta linear accelerator (Axesse with a Beam Modulator). The purpose of this study was to compare the calculated and measured doses with different chambers to establish the calculation accuracy of iPlan system. Methods: The iPlan has both Pencil beam (PB) and Monte Carlo (MC) calculation algorithms. Beam data include depth doses, profiles and output measurements for different field sizes. Collected data was verified by vendor and beam modelling was done. Further QA tests were carried out in our clinic. Dosemore » calculation accuracy verified point, volumetric dose measurement using ion chambers of different volumes (0.01cc and 0.125cc). Planner dose verification was done using diode array. Plans were generated in iPlan and irradiated in Elekta Axesse linear accelerator. Results: Dose calculation accuracies verified using ion chamber for 6 and 10 MV beam were 3.5+/-0.33(PB), 1.7%+/-0.7(MC) and 3.9%+/-0.6(PB), 3.4%+/-0.6(MC) respectively. Using a pin point chamber, dose calculation accuracy for 6MV and 10MV was 3.8%+/-0.06(PB), 1.21%+/-0.2(MC) and 4.2%+/-0.6(PB), 3.1%+/-0.7(MC) respectively. The calculated planar dose distribution for 10.4×10.4 cm2 was verified using a diode array and the gamma analysis for 2%-2mm criteria yielded pass rates of 88 %(PB) and 98.8%(MC) respectively. 3mm-3% yields 100% passing for both MC and PB algorithm. Conclusion: Dose calculation accuracy was found to be within acceptable limits for MC for 6MV beam. PB for both beams and MC for 10 MV beam were found to be outside acceptable limits. The output measurements were done twice for conformation. The lower gamma matching was attributed to meager number of measured profiles (only two profiles for PB) and coarse measurement resolution for diagonal profile measurement (5mm). Based on these measurements we concluded that 6 MV MC algorithm is suitable for patient treatment.« less
Validation of Calculations in a Digital Thermometer Firmware
NASA Astrophysics Data System (ADS)
Batagelj, V.; Miklavec, A.; Bojkovski, J.
2014-04-01
State-of-the-art digital thermometers are arguably remarkable measurement instruments, measuring outputs from resistance thermometers and/or thermocouples. Not only that they can readily achieve measuring accuracies in the parts-per-million range, but they also incorporate sophisticated algorithms for the transformation calculation of the measured resistance or voltage to temperature. These algorithms often include high-order polynomials, exponentials and logarithms, and must be performed using both standard coefficients and particular calibration coefficients. The numerical accuracy of these calculations and the associated uncertainty component must be much better than the accuracy of the raw measurement in order to be negligible in the total measurement uncertainty. In order for the end-user to gain confidence in these calculations as well as to conform to formal requirements of ISO/IEC 17025 and other standards, a way of validation of these numerical procedures performed in the firmware of the instrument is required. A software architecture which allows a simple validation of internal measuring instrument calculations is suggested. The digital thermometer should be able to expose all its internal calculation functions to the communication interface, so the end-user can compare the results of the internal measuring instrument calculation with reference results. The method can be regarded as a variation of the black-box software validation. Validation results on a thermometer prototype with implemented validation ability show that the calculation error of basic arithmetic operations is within the expected rounding error. For conversion functions, the calculation error is at least ten times smaller than the thermometer effective resolution for the particular probe type.
SU-E-T-455: Impact of Different Independent Dose Verification Software Programs for Secondary Check
DOE Office of Scientific and Technical Information (OSTI.GOV)
Itano, M; Yamazaki, T; Kosaka, M
2015-06-15
Purpose: There have been many reports for different dose calculation algorithms for treatment planning system (TPS). Independent dose verification program (IndpPro) is essential to verify clinical plans from the TPS. However, the accuracy of different independent dose verification programs was not evident. We conducted a multi-institutional study to reveal the impact of different IndpPros using different TPSs. Methods: Three institutes participated in this study. They used two different IndpPros (RADCALC and Simple MU Analysis (SMU), which implemented the Clarkson algorithm. RADCALC needed the input of radiological path length (RPL) computed by the TPSs (Eclipse or Pinnacle3). SMU used CT imagesmore » to compute the RPL independently from TPS). An ion-chamber measurement in water-equivalent phantom was performed to evaluate the accuracy of two IndpPros and the TPS in each institute. Next, the accuracy of dose calculation using the two IndpPros compared to TPS was assessed in clinical plan. Results: The accuracy of IndpPros and the TPSs in the homogenous phantom was +/−1% variation to the measurement. 1543 treatment fields were collected from the patients treated in the institutes. The RADCALC showed better accuracy (0.9 ± 2.2 %) than the SMU (1.7 ± 2.1 %). However, the accuracy was dependent on the TPS (Eclipse: 0.5%, Pinnacle3: 1.0%). The accuracy of RADCALC with Eclipse was similar to that of SMU in one of the institute. Conclusion: Depending on independent dose verification program, the accuracy shows systematic dose accuracy variation even though the measurement comparison showed a similar variation. The variation was affected by radiological path length calculation. IndpPro with Pinnacle3 has different variation because Pinnacle3 computed the RPL using physical density. Eclipse and SMU uses electron density, though.« less
Towards predictive many-body calculations of phonon-limited carrier mobilities in semiconductors
NASA Astrophysics Data System (ADS)
Poncé, Samuel; Margine, Elena R.; Giustino, Feliciano
2018-03-01
We probe the accuracy limit of ab initio calculations of carrier mobilities in semiconductors, within the framework of the Boltzmann transport equation. By focusing on the paradigmatic case of silicon, we show that fully predictive calculations of electron and hole mobilities require many-body quasiparticle corrections to band structures and electron-phonon matrix elements, the inclusion of spin-orbit coupling, and an extremely fine sampling of inelastic scattering processes in momentum space. By considering all these factors we obtain excellent agreement with experiment, and we identify the band effective masses as the most critical parameters to achieve predictive accuracy. Our findings set a blueprint for future calculations of carrier mobilities, and pave the way to engineering transport properties in semiconductors by design.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Surdoval, Wayne A.; Berry, David A.; Shultz, Travis R.
A set of equations are presented for calculating atomic principal spectral lines and fine-structure energy splits for single and multi-electron atoms. Calculated results are presented and compared to the National Institute of Science and Technology database demonstrating very good accuracy. The equations do not require fitted parameters. The only experimental parameter required is the Ionization energy for the electron of interest. The equations have comparable accuracy and broader applicability than the single electron Dirac equation. Three Appendices discuss the origin of the new equations and present calculated results. New insights into the special relativistic nature of the Dirac equation andmore » its relationship to the new equations are presented.« less
Evaluation of mechanical accuracy for couch‐based tracking system (CBTS)
Lee, Suk; Chang, Kyung‐Hwan; Shim, Jand Bo; Cao, Yuanjie; Lee, Chang Ki; Cho, Sam Ju; Yang, Dae Sik; Park, Young Je; Yoon, Won Seob
2012-01-01
This study evaluated the mechanical accuracy of an in‐house–developed couch‐based tracking system (CBTS) according to respiration data. The overall delay time of the CBTS was calculated, and the accuracy, reproducibility, and loading effect of the CBTS were evaluated according to the sinusoidal waveform and various respiratory motion data of real patients with and without a volunteer weighing 75 kg. The root mean square (rms) error of the accuracy, the reproducibility, and the sagging measurements were calculated for the three axes (X, Y, and Z directions) of the CBTS. The overall delay time of the CBTS was 0.251 sec. The accuracy and reproducibility in the Z direction in real patient data were poor, as indicated by high rms errors. The results of the loading effect were within 1.0 mm in all directions. This novel CBTS has the potential for clinical application for tumor tracking in radiation therapy. PACS number: 87.55.ne PMID:23149775
Determining the accuracy of maximum likelihood parameter estimates with colored residuals
NASA Technical Reports Server (NTRS)
Morelli, Eugene A.; Klein, Vladislav
1994-01-01
An important part of building high fidelity mathematical models based on measured data is calculating the accuracy associated with statistical estimates of the model parameters. Indeed, without some idea of the accuracy of parameter estimates, the estimates themselves have limited value. In this work, an expression based on theoretical analysis was developed to properly compute parameter accuracy measures for maximum likelihood estimates with colored residuals. This result is important because experience from the analysis of measured data reveals that the residuals from maximum likelihood estimation are almost always colored. The calculations involved can be appended to conventional maximum likelihood estimation algorithms. Simulated data runs were used to show that the parameter accuracy measures computed with this technique accurately reflect the quality of the parameter estimates from maximum likelihood estimation without the need for analysis of the output residuals in the frequency domain or heuristically determined multiplication factors. The result is general, although the application studied here is maximum likelihood estimation of aerodynamic model parameters from flight test data.
Achieving accuracy in first-principles calculations for EOS: basis completeness at high temperatures
NASA Astrophysics Data System (ADS)
Wills, John; Mattsson, Ann
2013-06-01
First-principles electronic structure calculations can provide EOS data in regimes of pressure and temperature where accurate experimental data is difficult or impossible to obtain. This lack, however, also precludes validation of calculations in those regimes. Factors that influence the accuracy of first-principles data include (1) theoretical approximations and (2) computational approximations used in implementing and solving the underlying equations. In the first category are the approximate exchange/correlation functionals and approximate wave equations approximating the Dirac equation; in the second are basis completeness, series convergence, and truncation errors. We are using two rather different electronic structure methods (VASP and RSPt) to make definitive the requirements for accuracy of the second type, common to both. In this talk, we discuss requirements for converged calculation at high temperature and moderated pressure. At convergence we show that both methods give identical results. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.
Optical properties of reduced graphene oxide and CuFe2O4 composites in the IR region
NASA Astrophysics Data System (ADS)
Ma, De-yue; Li, Xiao-xia; Guo, Yu-xiang; Zeng, Yu-run
2018-01-01
The complex refractive index of reduced graphene oxide and CuFe2O4 composites prepared by hydrothermal method was calculated using infrared Micro-reflective spectra and K-K relation, and the calculation errors were analyzed according to its IR transmission and spectral reflectivity calculated by Fresnel formula. And then normal emissivity of the composite in IR atmospheric window was calculated by means of Fresnel formula and modified refraction angle formula. The calculation accuracy was verified by comparing measured normal total emissivity with the calculated one. The results show that complex refractive index and normal emissivity calculated by the formulas have a high accuracy. It has been found that the composite has a good absorption and radiation characteristics in IR atmospheric window and a strong scattering ability in middle IR region by analyzing its extinction, absorption and radiation properties in IR region. Therefore, it may be used as IR absorption, extinction and radiation materials in some special fields.
Evaluation of various thrust calculation techniques on an F404 engine
NASA Technical Reports Server (NTRS)
Ray, Ronald J.
1990-01-01
In support of performance testing of the X-29A aircraft at the NASA-Ames, various thrust calculation techniques were developed and evaluated for use on the F404-GE-400 engine. The engine was thrust calibrated at NASA-Lewis. Results from these tests were used to correct the manufacturer's in-flight thrust program to more accurately calculate thrust for the specific test engine. Data from these tests were also used to develop an independent, simplified thrust calculation technique for real-time thrust calculation. Comparisons were also made to thrust values predicted by the engine specification model. Results indicate uninstalled gross thrust accuracies on the order of 1 to 4 percent for the various in-flight thrust methods. The various thrust calculations are described and their usage, uncertainty, and measured accuracies are explained. In addition, the advantages of a real-time thrust algorithm for flight test use and the importance of an accurate thrust calculation to the aircraft performance analysis are described. Finally, actual data obtained from flight test are presented.
A fast RCS accuracy assessment method for passive radar calibrators
NASA Astrophysics Data System (ADS)
Zhou, Yongsheng; Li, Chuanrong; Tang, Lingli; Ma, Lingling; Liu, QI
2016-10-01
In microwave radar radiometric calibration, the corner reflector acts as the standard reference target but its structure is usually deformed during the transportation and installation, or deformed by wind and gravity while permanently installed outdoor, which will decrease the RCS accuracy and therefore the radiometric calibration accuracy. A fast RCS accuracy measurement method based on 3-D measuring instrument and RCS simulation was proposed in this paper for tracking the characteristic variation of the corner reflector. In the first step, RCS simulation algorithm was selected and its simulation accuracy was assessed. In the second step, the 3-D measuring instrument was selected and its measuring accuracy was evaluated. Once the accuracy of the selected RCS simulation algorithm and 3-D measuring instrument was satisfied for the RCS accuracy assessment, the 3-D structure of the corner reflector would be obtained by the 3-D measuring instrument, and then the RCSs of the obtained 3-D structure and corresponding ideal structure would be calculated respectively based on the selected RCS simulation algorithm. The final RCS accuracy was the absolute difference of the two RCS calculation results. The advantage of the proposed method was that it could be applied outdoor easily, avoiding the correlation among the plate edge length error, plate orthogonality error, plate curvature error. The accuracy of this method is higher than the method using distortion equation. In the end of the paper, a measurement example was presented in order to show the performance of the proposed method.
High-Accuracy Finite Element Method: Benchmark Calculations
NASA Astrophysics Data System (ADS)
Gusev, Alexander; Vinitsky, Sergue; Chuluunbaatar, Ochbadrakh; Chuluunbaatar, Galmandakh; Gerdt, Vladimir; Derbov, Vladimir; Góźdź, Andrzej; Krassovitskiy, Pavel
2018-02-01
We describe a new high-accuracy finite element scheme with simplex elements for solving the elliptic boundary-value problems and show its efficiency on benchmark solutions of the Helmholtz equation for the triangle membrane and hypercube.
Advanced Neutronics Tools for BWR Design Calculations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Santamarina, A.; Hfaiedh, N.; Letellier, R.
2006-07-01
This paper summarizes the developments implemented in the new APOLLO2.8 neutronics tool to meet the required target accuracy in LWR applications, particularly void effects and pin-by-pin power map in BWRs. The Method Of Characteristics was developed to allow efficient LWR assembly calculations in 2D-exact heterogeneous geometry; resonant reaction calculation was improved by the optimized SHEM-281 group mesh, which avoids resonance self-shielding approximation below 23 eV, and the new space-dependent method for resonant mixture that accounts for resonance overlapping. Furthermore, a new library CEA2005, processed from JEFF3.1 evaluations involving feedback from Critical Experiments and LWR P.I.E, is used. The specific '2005-2007more » BWR Plan' settled to demonstrate the validation/qualification of this neutronics tool is described. Some results from the validation process are presented: the comparison of APOLLO2.8 results to reference Monte Carlo TRIPOLI4 results on specific BWR benchmarks emphasizes the ability of the deterministic tool to calculate BWR assembly multiplication factor within 200 pcm accuracy for void fraction varying from 0 to 100%. The qualification process against the BASALA mock-up experiment stresses APOLLO2.8/CEA2005 performances: pin-by-pin power is always predicted within 2% accuracy, reactivity worth of B4C or Hf cruciform control blade, as well as Gd pins, is predicted within 1.2% accuracy. (authors)« less
Discussion on accuracy degree evaluation of accident velocity reconstruction model
NASA Astrophysics Data System (ADS)
Zou, Tiefang; Dai, Yingbiao; Cai, Ming; Liu, Jike
In order to investigate the applicability of accident velocity reconstruction model in different cases, a method used to evaluate accuracy degree of accident velocity reconstruction model is given. Based on pre-crash velocity in theory and calculation, an accuracy degree evaluation formula is obtained. With a numerical simulation case, Accuracy degrees and applicability of two accident velocity reconstruction models are analyzed; results show that this method is feasible in practice.
Print to Braille: Preparation and Accuracy of Mathematics Materials in K-12 Education
ERIC Educational Resources Information Center
Herzberg, Tina S.; Rosenblum, L. Penny
2014-01-01
Introduction: This study analyzed the accuracy of 107 mathematics worksheets prepared for tactile learners. The mean number of errors was calculated, and we examined whether there was a significant difference in the level of accuracy based on National Library Service for the Blind and Physically Handicapped (NLS) certification or job role of…
Determination of the Optimal Fourier Number on the Dynamic Thermal Transmission
NASA Astrophysics Data System (ADS)
Bruzgevičius, P.; Burlingis, A.; Norvaišienė, R.
2016-12-01
This article represents the result of experimental research on transient heat transfer in a multilayered (heterogeneous) wall. Our non-steady thermal transmission simulation is based on a finite-difference calculation method. The value of a Fourier number shows the similarity of thermal variation in conditional layers of an enclosure. Most scientists recommend using no more than a value of 0.5 for the Fourier number when performing calculations on dynamic (transient) heat transfer. The value of the Fourier number is determined in order to acquire reliable calculation results with optimal accuracy. To compare the results of simulation with experimental research, a transient heat transfer calculation spreadsheet was created. Our research has shown that a Fourier number of around 0.5 or even 0.32 is not sufficient ({≈ }17 % of oscillation amplitude) for calculations of transient heat transfer in a multilayered wall. The least distorted calculation results were obtained when the multilayered enclosure was divided into conditional layers with almost equal Fourier number values and when the value of the Fourier number was around 1/6, i.e., approximately 0.17. Statistical deviation analysis using the Statistical Analysis System was applied to assess the accuracy of the spreadsheet calculation and was developed on the basis of our established methodology. The mean and median absolute error as well as their confidence intervals has been estimated by the two methods with optimal accuracy ({F}_{oMDF}= 0.177 and F_{oEPS}= 0.1633 values).
Dosimetric evaluation of a Monte Carlo IMRT treatment planning system incorporating the MIMiC
NASA Astrophysics Data System (ADS)
Rassiah-Szegedi, P.; Fuss, M.; Sheikh-Bagheri, D.; Szegedi, M.; Stathakis, S.; Lancaster, J.; Papanikolaou, N.; Salter, B.
2007-12-01
The high dose per fraction delivered to lung lesions in stereotactic body radiation therapy (SBRT) demands high dose calculation and delivery accuracy. The inhomogeneous density in the thoracic region along with the small fields used typically in intensity-modulated radiation therapy (IMRT) treatments poses a challenge in the accuracy of dose calculation. In this study we dosimetrically evaluated a pre-release version of a Monte Carlo planning system (PEREGRINE 1.6b, NOMOS Corp., Cranberry Township, PA), which incorporates the modeling of serial tomotherapy IMRT treatments with the binary multileaf intensity modulating collimator (MIMiC). The aim of this study is to show the validation process of PEREGRINE 1.6b since it was used as a benchmark to investigate the accuracy of doses calculated by a finite size pencil beam (FSPB) algorithm for lung lesions treated on the SBRT dose regime via serial tomotherapy in our previous study. Doses calculated by PEREGRINE were compared against measurements in homogeneous and inhomogeneous materials carried out on a Varian 600C with a 6 MV photon beam. Phantom studies simulating various sized lesions were also carried out to explain some of the large dose discrepancies seen in the dose calculations with small lesions. Doses calculated by PEREGRINE agreed to within 2% in water and up to 3% for measurements in an inhomogeneous phantom containing lung, bone and unit density tissue.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, X; Kantor, M; Zhu, X
2014-06-01
Purpose: To evaluate the dosimetric accuracy for proton therapy patients with metal implants in CT using metal deletion technique (MDT) artifacts reduction. Methods: Proton dose accuracies under CT metal artifacts were first evaluated using a water phantom with cylindrical inserts of different materials (titanium and steel). Ranges and dose profiles along different beam angles were calculated using treatment planning system (Eclipse version 8.9) on uncorrected CT, MDT CT, and manually-corrected CT, where true Hounsfield units (water) were assigned to the streak artifacts. In patient studies, the treatment plans were developed on manually-corrected CTs, then recalculated on MDT and uncorrected CTs.more » DVH indices were compared between the dose distributions on all the CTs. Results: For water phantom study with 1/2 inch titanium insert, the proton range differences estimated by MDT CT were with 1% for all beam angles, while the range error can be up to 2.6% for uncorrected CT. For the study with 1 inch stainless steel insert, the maximum range error calculated by MDT CT was 1.09% among all the beam angles compared with maximum range error with 4.7% for uncorrected CT. The dose profiles calculated on MDT CTs for both titanium and steel inserts showed very good agreements with the ones calculated on manually-corrected CTs, while large dose discrepancies calculated using uncorrected CTs were observed in the distal end region of the proton beam. The patient study showed similar dose distribution and DVHs for organs near the metal artifacts recalculated on MDT CT compared with the ones calculated on manually-corrected CT, while the differences between uncorrected and corrected CTs were much pronounced. Conclusion: In proton therapy, large dose error could occur due to metal artifact. The MDT CT can be used for proton dose calculation to achieve similar dose accuracy as the current clinical practice using manual correction.« less
Shirey, Robert J; Wu, Hsinshun Terry
2018-01-01
This study quantifies the dosimetric accuracy of a commercial treatment planning system as functions of treatment depth, air gap, and range shifter thickness for superficial pencil beam scanning proton therapy treatments. The RayStation 6 pencil beam and Monte Carlo dose engines were each used to calculate the dose distributions for a single treatment plan with varying range shifter air gaps. Central axis dose values extracted from each of the calculated plans were compared to dose values measured with a calibrated PTW Markus chamber at various depths in RW3 solid water. Dose was measured at 12 depths, ranging from the surface to 5 cm, for each of the 18 different air gaps, which ranged from 0.5 to 28 cm. TPS dosimetric accuracy, defined as the ratio of calculated dose relative to the measured dose, was plotted as functions of depth and air gap for the pencil beam and Monte Carlo dose algorithms. The accuracy of the TPS pencil beam dose algorithm was found to be clinically unacceptable at depths shallower than 3 cm with air gaps wider than 10 cm, and increased range shifter thickness only added to the dosimetric inaccuracy of the pencil beam algorithm. Each configuration calculated with Monte Carlo was determined to be clinically acceptable. Further comparisons of the Monte Carlo dose algorithm to the measured spread-out Bragg Peaks of multiple fields used during machine commissioning verified the dosimetric accuracy of Monte Carlo in a variety of beam energies and field sizes. Discrepancies between measured and TPS calculated dose values can mainly be attributed to the ability (or lack thereof) of the TPS pencil beam dose algorithm to properly model secondary proton scatter generated in the range shifter. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.
Validation of cardiac accelerometer sensor measurements.
Remme, Espen W; Hoff, Lars; Halvorsen, Per Steinar; Naerum, Edvard; Skulstad, Helge; Fleischer, Lars A; Elle, Ole Jakob; Fosse, Erik
2009-12-01
In this study we have investigated the accuracy of an accelerometer sensor designed for the measurement of cardiac motion and automatic detection of motion abnormalities caused by myocardial ischaemia. The accelerometer, attached to the left ventricular wall, changed its orientation relative to the direction of gravity during the cardiac cycle. This caused a varying gravity component in the measured acceleration signal that introduced an error in the calculation of myocardial motion. Circumferential displacement, velocity and rotation of the left ventricular apical region were calculated from the measured acceleration signal. We developed a mathematical method to separate translational and gravitational acceleration components based on a priori assumptions of myocardial motion. The accuracy of the measured motion was investigated by comparison with known motion of a robot arm programmed to move like the heart wall. The accuracy was also investigated in an animal study. The sensor measurements were compared with simultaneously recorded motion from a robot arm attached next to the sensor on the heart and with measured motion by echocardiography and a video camera. The developed compensation method for the varying gravity component improved the accuracy of the calculated velocity and displacement traces, giving very good agreement with the reference methods.
A holistic calibration method with iterative distortion compensation for stereo deflectometry
NASA Astrophysics Data System (ADS)
Xu, Yongjia; Gao, Feng; Zhang, Zonghua; Jiang, Xiangqian
2018-07-01
This paper presents a novel holistic calibration method for stereo deflectometry system to improve the system measurement accuracy. The reconstruction result of stereo deflectometry is integrated with the calculated normal data of the measured surface. The calculation accuracy of the normal data is seriously influenced by the calibration accuracy of the geometrical relationship of the stereo deflectometry system. Conventional calibration approaches introduce form error to the system due to inaccurate imaging model and distortion elimination. The proposed calibration method compensates system distortion based on an iterative algorithm instead of the conventional distortion mathematical model. The initial value of the system parameters are calculated from the fringe patterns displayed on the systemic LCD screen through a reflection of a markless flat mirror. An iterative algorithm is proposed to compensate system distortion and optimize camera imaging parameters and system geometrical relation parameters based on a cost function. Both simulation work and experimental results show the proposed calibration method can significantly improve the calibration and measurement accuracy of a stereo deflectometry. The PV (peak value) of measurement error of a flat mirror can be reduced to 69.7 nm by applying the proposed method from 282 nm obtained with the conventional calibration approach.
NASA Astrophysics Data System (ADS)
Li, Sui-xian; Chen, Haiyang; Sun, Min; Cheng, Zaijun
2009-11-01
Aimed at improving the calculation accuracy when calculating the energy deposition of electrons traveling in solids, a method we call optimal subdivision number searching algorithm is proposed. When treating the energy deposition of electrons traveling in solids, large calculation errors are found, we are conscious of that it is the result of dividing and summing when calculating the integral. Based on the results of former research, we propose a further subdividing and summing method. For β particles with the energy in the entire spectrum span, the energy data is set only to be the integral multiple of keV, and the subdivision number is set to be from 1 to 30, then the energy deposition calculation error collections are obtained. Searching for the minimum error in the collections, we can obtain the corresponding energy and subdivision number pairs, as well as the optimal subdivision number. The method is carried out in four kinds of solid materials, Al, Si, Ni and Au to calculate energy deposition. The result shows that the calculation error is reduced by one order with the improved algorithm.
NASA Astrophysics Data System (ADS)
Vanicek, Jiri
2014-03-01
Rigorous quantum-mechanical calculations of coherent ultrafast electronic spectra remain difficult. I will present several approaches developed in our group that increase the efficiency and accuracy of such calculations: First, we justified the feasibility of evaluating time-resolved spectra of large systems by proving that the number of trajectories needed for convergence of the semiclassical dephasing representation/phase averaging is independent of dimensionality. Recently, we further accelerated this approximation with a cellular scheme employing inverse Weierstrass transform and optimal scaling of the cell size. The accuracy of potential energy surfaces was increased by combining the dephasing representation with accurate on-the-fly ab initio electronic structure calculations, including nonadiabatic and spin-orbit couplings. Finally, the inherent semiclassical approximation was removed in the exact quantum Gaussian dephasing representation, in which semiclassical trajectories are replaced by communicating frozen Gaussian basis functions evolving classically with an average Hamiltonian. Among other examples I will present an on-the-fly ab initio semiclassical dynamics calculation of the dispersed time-resolved stimulated emission spectrum of the 54-dimensional azulene. This research was supported by EPFL and by the Swiss National Science Foundation NCCR MUST (Molecular Ultrafast Science and Technology) and Grant No. 200021124936/1.
FreeSASA: An open source C library for solvent accessible surface area calculations.
Mitternacht, Simon
2016-01-01
Calculating solvent accessible surface areas (SASA) is a run-of-the-mill calculation in structural biology. Although there are many programs available for this calculation, there are no free-standing, open-source tools designed for easy tool-chain integration. FreeSASA is an open source C library for SASA calculations that provides both command-line and Python interfaces in addition to its C API. The library implements both Lee and Richards' and Shrake and Rupley's approximations, and is highly configurable to allow the user to control molecular parameters, accuracy and output granularity. It only depends on standard C libraries and should therefore be easy to compile and install on any platform. The library is well-documented, stable and efficient. The command-line interface can easily replace closed source legacy programs, with comparable or better accuracy and speed, and with some added functionality.
A new BP Fourier algorithm and its application in English teaching evaluation
NASA Astrophysics Data System (ADS)
Pei, Xuehui; Pei, Guixin
2017-08-01
BP neural network algorithm has wide adaptability and accuracy when used in complicated system evaluation, but its calculation defects such as slow convergence have limited its practical application. The paper tries to speed up the calculation convergence of BP neural network algorithm with Fourier basis functions and presents a new BP Fourier algorithm for complicated system evaluation. First, shortages and working principle of BP algorithm are analyzed for subsequent targeted improvement; Second, the presented BP Fourier algorithm adopts Fourier basis functions to simplify calculation structure, designs new calculation transfer function between input and output layers, and conducts theoretical analysis to prove the efficiency of the presented algorithm; Finally, the presented algorithm is used in evaluating university English teaching and the application results shows that the presented BP Fourier algorithm has better performance in calculation efficiency and evaluation accuracy and can be used in evaluating complicated system practically.
Creep of Hi-Nicalon S Ceramic Fiber Tows at 800 deg C in Air and in Silicic Acid-Saturated Steam
2015-12-26
earliest recorded instances is that of Egyptian brick making. As far back as approximately 1500 BC, Egyptians added straw to clay for bricks [3]. This...The accuracy of this calculation method depends on the accuracy of amorphous silica viscosity data, which, in turn, are affected by impurities in...the SiC fiber. Lack of availability of viscosity data for crystobalite and tridymite pre- cluded calculation of growth stresses in crystallized silica
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Gaigong; Lin, Lin, E-mail: linlin@math.berkeley.edu; Computational Research Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
Recently, we have proposed the adaptive local basis set for electronic structure calculations based on Kohn–Sham density functional theory in a pseudopotential framework. The adaptive local basis set is efficient and systematically improvable for total energy calculations. In this paper, we present the calculation of atomic forces, which can be used for a range of applications such as geometry optimization and molecular dynamics simulation. We demonstrate that, under mild assumptions, the computation of atomic forces can scale nearly linearly with the number of atoms in the system using the adaptive local basis set. We quantify the accuracy of the Hellmann–Feynmanmore » forces for a range of physical systems, benchmarked against converged planewave calculations, and find that the adaptive local basis set is efficient for both force and energy calculations, requiring at most a few tens of basis functions per atom to attain accuracies required in practice. Since the adaptive local basis set has implicit dependence on atomic positions, Pulay forces are in general nonzero. However, we find that the Pulay force is numerically small and systematically decreasing with increasing basis completeness, so that the Hellmann–Feynman force is sufficient for basis sizes of a few tens of basis functions per atom. We verify the accuracy of the computed forces in static calculations of quasi-1D and 3D disordered Si systems, vibration calculation of a quasi-1D Si system, and molecular dynamics calculations of H{sub 2} and liquid Al–Si alloy systems, where we show systematic convergence to benchmark planewave results and results from the literature.« less
Zhang, Gaigong; Lin, Lin; Hu, Wei; ...
2017-01-27
Recently, we have proposed the adaptive local basis set for electronic structure calculations based on Kohn–Sham density functional theory in a pseudopotential framework. The adaptive local basis set is efficient and systematically improvable for total energy calculations. In this paper, we present the calculation of atomic forces, which can be used for a range of applications such as geometry optimization and molecular dynamics simulation. We demonstrate that, under mild assumptions, the computation of atomic forces can scale nearly linearly with the number of atoms in the system using the adaptive local basis set. We quantify the accuracy of the Hellmann–Feynmanmore » forces for a range of physical systems, benchmarked against converged planewave calculations, and find that the adaptive local basis set is efficient for both force and energy calculations, requiring at most a few tens of basis functions per atom to attain accuracies required in practice. Sin ce the adaptive local basis set has implicit dependence on atomic positions, Pulay forces are in general nonzero. However, we find that the Pulay force is numerically small and systematically decreasing with increasing basis completeness, so that the Hellmann–Feynman force is sufficient for basis sizes of a few tens of basis functions per atom. We verify the accuracy of the computed forces in static calculations of quasi-1D and 3D disordered Si systems, vibration calculation of a quasi-1D Si system, and molecular dynamics calculations of H 2 and liquid Al–Si alloy systems, where we show systematic convergence to benchmark planewave results and results from the literature.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Gaigong; Lin, Lin; Hu, Wei
Recently, we have proposed the adaptive local basis set for electronic structure calculations based on Kohn–Sham density functional theory in a pseudopotential framework. The adaptive local basis set is efficient and systematically improvable for total energy calculations. In this paper, we present the calculation of atomic forces, which can be used for a range of applications such as geometry optimization and molecular dynamics simulation. We demonstrate that, under mild assumptions, the computation of atomic forces can scale nearly linearly with the number of atoms in the system using the adaptive local basis set. We quantify the accuracy of the Hellmann–Feynmanmore » forces for a range of physical systems, benchmarked against converged planewave calculations, and find that the adaptive local basis set is efficient for both force and energy calculations, requiring at most a few tens of basis functions per atom to attain accuracies required in practice. Sin ce the adaptive local basis set has implicit dependence on atomic positions, Pulay forces are in general nonzero. However, we find that the Pulay force is numerically small and systematically decreasing with increasing basis completeness, so that the Hellmann–Feynman force is sufficient for basis sizes of a few tens of basis functions per atom. We verify the accuracy of the computed forces in static calculations of quasi-1D and 3D disordered Si systems, vibration calculation of a quasi-1D Si system, and molecular dynamics calculations of H 2 and liquid Al–Si alloy systems, where we show systematic convergence to benchmark planewave results and results from the literature.« less
NASA Astrophysics Data System (ADS)
Zhang, Gaigong; Lin, Lin; Hu, Wei; Yang, Chao; Pask, John E.
2017-04-01
Recently, we have proposed the adaptive local basis set for electronic structure calculations based on Kohn-Sham density functional theory in a pseudopotential framework. The adaptive local basis set is efficient and systematically improvable for total energy calculations. In this paper, we present the calculation of atomic forces, which can be used for a range of applications such as geometry optimization and molecular dynamics simulation. We demonstrate that, under mild assumptions, the computation of atomic forces can scale nearly linearly with the number of atoms in the system using the adaptive local basis set. We quantify the accuracy of the Hellmann-Feynman forces for a range of physical systems, benchmarked against converged planewave calculations, and find that the adaptive local basis set is efficient for both force and energy calculations, requiring at most a few tens of basis functions per atom to attain accuracies required in practice. Since the adaptive local basis set has implicit dependence on atomic positions, Pulay forces are in general nonzero. However, we find that the Pulay force is numerically small and systematically decreasing with increasing basis completeness, so that the Hellmann-Feynman force is sufficient for basis sizes of a few tens of basis functions per atom. We verify the accuracy of the computed forces in static calculations of quasi-1D and 3D disordered Si systems, vibration calculation of a quasi-1D Si system, and molecular dynamics calculations of H2 and liquid Al-Si alloy systems, where we show systematic convergence to benchmark planewave results and results from the literature.
Lee, S. A.; Kong, C.; Adeola, O.; Kim, B. G.
2016-01-01
Estimation of feed intake (FI) for individual animals within a pen is needed in situations where more than one animal share a feeder during feeding trials. A partitioning method (PM) was previously published as a model to estimate the individual FI (IFI). Briefly, the IFI of a pig within the pen was calculated by partitioning IFI into IFI for maintenance (IFIm) and IFI for growth. In the PM, IFIm is determined based on the metabolic body weight (BW), which is calculated using the coefficient of 106 and exponent of 0.75. Two simulation studies were conducted to test the hypothesis that the use of different coefficients and exponents for metabolic BW to calculate IFIm improves the accuracy of the estimates of IFI for pigs, and that PM is applied to pigs fed in group-housing systems. The accuracy of prediction represented by difference between actual and estimated IFI was compared using PM, ratio (RM), or averaging method (AM). In simulation studies 1 and 2, the PM estimated IFI better than the AM and RM during most of the periods (p<0.05). The use of 0.60 as the exponent and the coefficient of 197 to calculate metabolic BW did not improve the accuracy of the IFI estimates in both simulation studies 1 and 2. The results imply that the use of 197 kcal×kg BW0.60 as metabolizable energy for maintenance in PM does not improve the accuracy of IFI estimations compared with the use of 106 kcal×kg BW0.75 and that the PM estimates the IFI of pigs with greater accuracy compared with the averaging or ratio methods in group-housing systems. PMID:27608642
NASA Astrophysics Data System (ADS)
Baturin, A. P.
2011-07-01
The results of major planets' and Moon's ephemerides smoothing by cubic polynomials are presented. Considered ephemerides are DE405, DE406, DE408, DE421, DE423 and DE722. The goal of the smoothig is an elimination of discontinu-ous behavior of interpolated coordinates and their derivatives at the junctions of adjacent interpolation intervals when calculations are made with 34-digit decimal accuracy. The reason of such a behavior is a limited 16-digit decimal accuracy of coefficients in ephemerides for interpolating Chebyshev's polynomials. Such discontinuity of perturbing bodies' coordinates signifi-cantly reduces the advantages of 34-digit calculations because the accuracy of numerical integration of asteroids' motion equations increases in this case just by 3 orders to compare with 16-digit calculations. It is demonstrated that the cubic-polynomial smoothing of ephemerides results in elimination of jumps of perturbing bodies' coordinates and their derivatives. This leads to increasing of numerical integration accuracy by 7-9 orders. All calculations in this work were made with 34-digit decimal accuracy on the computer cluster "Skif Cyberia" of Tomsk State University.
Isma’eel, Hussain A.; Sakr, George E.; Almedawar, Mohamad M.; Fathallah, Jihan; Garabedian, Torkom; Eddine, Savo Bou Zein
2015-01-01
Background High dietary salt intake is directly linked to hypertension and cardiovascular diseases (CVDs). Predicting behaviors regarding salt intake habits is vital to guide interventions and increase their effectiveness. We aim to compare the accuracy of an artificial neural network (ANN) based tool that predicts behavior from key knowledge questions along with clinical data in a high cardiovascular risk cohort relative to the least square models (LSM) method. Methods We collected knowledge, attitude and behavior data on 115 patients. A behavior score was calculated to classify patients’ behavior towards reducing salt intake. Accuracy comparison between ANN and regression analysis was calculated using the bootstrap technique with 200 iterations. Results Starting from a 69-item questionnaire, a reduced model was developed and included eight knowledge items found to result in the highest accuracy of 62% CI (58-67%). The best prediction accuracy in the full and reduced models was attained by ANN at 66% and 62%, respectively, compared to full and reduced LSM at 40% and 34%, respectively. The average relative increase in accuracy over all in the full and reduced models is 82% and 102%, respectively. Conclusions Using ANN modeling, we can predict salt reduction behaviors with 66% accuracy. The statistical model has been implemented in an online calculator and can be used in clinics to estimate the patient’s behavior. This will help implementation in future research to further prove clinical utility of this tool to guide therapeutic salt reduction interventions in high cardiovascular risk individuals. PMID:26090333
Ladner, Travis R; Dewan, Michael C; Day, Matthew A; Shannon, Chevis N; Tomycz, Luke; Tulipan, Noel; Wellons, John C
2015-08-01
OBJECT Osseous anomalies of the craniocervical junction are hypothesized to precipitate the hindbrain herniation observed in Chiari I malformation (CM-I). Previous work by Tubbs et al. showed that posterior angulation of the odontoid process is more prevalent in children with CM-I than in healthy controls. The present study is an external validation of that report. The goals of our study were 3-fold: 1) to externally validate the results of Tubbs et al. in a different patient population; 2) to compare how morphometric parameters vary with age, sex, and symptomatology; and 3) to develop a correlative model for tonsillar ectopia in CM-I based on these measurements. METHODS The authors performed a retrospective review of 119 patients who underwent posterior fossa decompression with duraplasty at the Monroe Carell Jr. Children's Hospital at Vanderbilt University; 78 of these patients had imaging available for review. Demographic and clinical variables were collected. A neuroradiologist retrospectively evaluated preoperative MRI examinations in these 78 patients and recorded the following measurements: McRae line length; obex displacement length; odontoid process parameters (height, angle of retroflexion, and angle of retroversion); perpendicular distance to the basion-C2 line (pB-C2 line); length of cerebellar tonsillar ectopia; caudal extent of the cerebellar tonsils; and presence, location, and size of syringomyelia. Odontoid retroflexion grade was classified as Grade 0, > 90°; Grade I,85°-89°; Grade II, 80°-84°; and Grade III, < 80°. Age groups were defined as 0-6 years, 7-12 years, and 13-17 years at the time of surgery. Univariate and multivariate linear regression analyses, Kruskal-Wallis 1-way ANOVA, and Fisher's exact test were performed to assess the relationship between age, sex, and symptomatology with these craniometric variables. RESULTS The prevalence of posterior odontoid angulation was 81%, which is almost identical to that in the previous report (84%). With increasing age, the odontoid height (p < 0.001) and pB-C2 length (p < 0.001) increased, while the odontoid process became more posteriorly inclined (p = 0.010). The pB-C2 line was significantly longer in girls (p = 0.006). These measurements did not significantly correlate with symptomatology. Length of tonsillar ectopia in pediatric CM-I correlated with an enlarged foramen magnum (p = 0.023), increasing obex displacement (p = 0.020), and increasing odontoid retroflexion (p < 0.001). CONCLUSIONS Anomalous bony development of the craniocervical junction is a consistent feature of CM-I in children. The authors found that the population at their center was characterized by posterior angulation of the odontoid process in 81% of cases, similar to findings by Tubbs et al. (84%). The odontoid process appeared to lengthen and become more posteriorly inclined with age. Increased tonsillar ectopia was associated with more posterior odontoid angulation, a widened foramen magnum, and an inferiorly displaced obex.
Sulimov, Alexey V; Kutov, Danil C; Katkova, Ekaterina V; Ilin, Ivan S; Sulimov, Vladimir B
2017-11-01
Discovery of new inhibitors of the protein associated with a given disease is the initial and most important stage of the whole process of the rational development of new pharmaceutical substances. New inhibitors block the active site of the target protein and the disease is cured. Computer-aided molecular modeling can considerably increase effectiveness of new inhibitors development. Reliable predictions of the target protein inhibition by a small molecule, ligand, is defined by the accuracy of docking programs. Such programs position a ligand in the target protein and estimate the protein-ligand binding energy. Positioning accuracy of modern docking programs is satisfactory. However, the accuracy of binding energy calculations is too low to predict good inhibitors. For effective application of docking programs to new inhibitors development the accuracy of binding energy calculations should be higher than 1kcal/mol. Reasons of limited accuracy of modern docking programs are discussed. One of the most important aspects limiting this accuracy is imperfection of protein-ligand energy calculations. Results of supercomputer validation of several force fields and quantum-chemical methods for docking are presented. The validation was performed by quasi-docking as follows. First, the low energy minima spectra of 16 protein-ligand complexes were found by exhaustive minima search in the MMFF94 force field. Second, energies of the lowest 8192 minima are recalculated with CHARMM force field and PM6-D3H4X and PM7 quantum-chemical methods for each complex. The analysis of minima energies reveals the docking positioning accuracies of the PM7 and PM6-D3H4X quantum-chemical methods and the CHARMM force field are close to one another and they are better than the positioning accuracy of the MMFF94 force field. Copyright © 2017 Elsevier Inc. All rights reserved.
Development of Ultra-Fine Multigroup Cross Section Library of the AMPX/SCALE Code Packages
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jeon, Byoung Kyu; Sik Yang, Won; Kim, Kang Seog
The Consortium for Advanced Simulation of Light Water Reactors Virtual Environment for Reactor Applications (VERA) neutronic simulator MPACT is being developed by Oak Ridge National Laboratory and the University of Michigan for various reactor applications. The MPACT and simplified MPACT 51- and 252-group cross section libraries have been developed for the MPACT neutron transport calculations by using the AMPX and Standardized Computer Analyses for Licensing Evaluations (SCALE) code packages developed at Oak Ridge National Laboratory. It has been noted that the conventional AMPX/SCALE procedure has limited applications for fast-spectrum systems such as boiling water reactor (BWR) fuels with very highmore » void fractions and fast reactor fuels because of its poor accuracy in unresolved and fast energy regions. This lack of accuracy can introduce additional error sources to MPACT calculations, which is already limited by the Bondarenko approach for resolved resonance self-shielding calculation. To enhance the prediction accuracy of MPACT for fast-spectrum reactor analyses, the accuracy of the AMPX/SCALE code packages should be improved first. The purpose of this study is to identify the major problems of the AMPX/SCALE procedure in generating fast-spectrum cross sections and to devise ways to improve the accuracy. For this, various benchmark problems including a typical pressurized water reactor fuel, BWR fuels with various void fractions, and several fast reactor fuels were analyzed using the AMPX 252-group libraries. Isotopic reaction rates were determined by SCALE multigroup (MG) calculations and compared with continuous energy (CE) Monte Carlo calculation results. This reaction rate analysis revealed three main contributors to the observed differences in reactivity and reaction rates: (1) the limitation of the Bondarenko approach in coarse energy group structure, (2) the normalization issue of probability tables, and (3) neglect of the self-shielding effect of resonance-like cross sections at high energy range such as (n,p) cross section of Cl35. The first error source can be eliminated by an ultra-fine group (UFG) structure in which the broad scattering resonances of intermediate-weight nuclides can be represented accurately by a piecewise constant function. A UFG AMPX library was generated with modified probability tables and tested against various benchmark problems. The reactivity and reaction rates determined with the new UFG AMPX library agreed very well with respect to Monte Carlo Neutral Particle (MCNP) results. To enhance the lattice calculation accuracy without significantly increasing the computational time, performing the UFG lattice calculation in two steps was proposed. In the first step, a UFG slowing-down calculation is performed for the corresponding homogenized composition, and UFG cross sections are collapsed into an intermediate group structure. In the second step, the lattice calculation is performed for the intermediate group level using the condensed group cross sections. A preliminary test showed that the condensed library reproduces the results obtained with the UFG cross section library. This result suggests that the proposed two-step lattice calculation approach is a promising option to enhance the applicability of the AMPX/SCALE system to fast system analysis.« less
NASA Astrophysics Data System (ADS)
Bakhvalov, Yu A.; Grechikhin, V. V.; Yufanova, A. L.
2016-04-01
The article describes the calculation of the magnetic fields in the problems diagnostic of technical systems based on the full-scale modeling experiment. Use of gridless fundamental solution method and its variants in combination with grid methods (finite differences and finite elements) are allowed to considerably reduce the dimensionality task of the field calculation and hence to reduce calculation time. When implementing the method are used fictitious magnetic charges. In addition, much attention is given to the calculation accuracy. Error occurs when wrong choice of the distance between the charges. The authors are proposing to use vector magnetic dipoles to improve the accuracy of magnetic fields calculation. Examples of this approacharegiven. The article shows the results of research. They are allowed to recommend the use of this approach in the method of fundamental solutions for the full-scale modeling tests of technical systems.
A Comparison of Three Theoretical Methods of Calculating Span Load Distribution on Swept Wings
NASA Technical Reports Server (NTRS)
VanDorn, Nicholas H.; DeYoung, John
1947-01-01
Three methods for calculating span load distribution, those developed by V.M Falkner, Wm. Mutterperl, and J. Weissinger, have been applied to five swept wings. The angles of sweep ranged from -45 degrees to +45 degrees. These methods were examined to establish their relative accuracy and case of application. Experimentally determined loadings were used as a basis for judging accuracy. For the convenience of the readers the computing forms and all information requisite to their application are included in appendixes. From the analysis it was found that the Weissinger method would be best suited to an over-all study of the effects of plan form on the span loading and associated characteristics of wings. The method gave good, but not best, accuracy and involved by far the least computing effort. The Falkner method gave the best accuracy but at a considerable expanse in computing effort and hence appeared to be most useful for a detailed study of a specific wing. The Mutterperl method offered no advantages in accuracy of facility over either of the other methods and hence is not recommended for use.
Nonuniform fast Fourier transform method for numerical diffraction simulation on tilted planes.
Xiao, Yu; Tang, Xiahui; Qin, Yingxiong; Peng, Hao; Wang, Wei; Zhong, Lijing
2016-10-01
The method, based on the rotation of the angular spectrum in the frequency domain, is generally used for the diffraction simulation between the tilted planes. Due to the rotation of the angular spectrum, the interval between the sampling points in the Fourier domain is not even. For the conventional fast Fourier transform (FFT)-based methods, a spectrum interpolation is needed to get the approximate sampling value on the equidistant sampling points. However, due to the numerical error caused by the spectrum interpolation, the calculation accuracy degrades very quickly as the rotation angle increases. Here, the diffraction propagation between the tilted planes is transformed into a problem about the discrete Fourier transform on the uneven sampling points, which can be evaluated effectively and precisely through the nonuniform fast Fourier transform method (NUFFT). The most important advantage of this method is that the conventional spectrum interpolation is avoided and the high calculation accuracy can be guaranteed for different rotation angles, even when the rotation angle is close to π/2. Also, its calculation efficiency is comparable with that of the conventional FFT-based methods. Numerical examples as well as a discussion about the calculation accuracy and the sampling method are presented.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Park, Peter C.; Schreibmann, Eduard; Roper, Justin
2015-03-15
Purpose: Computed tomography (CT) artifacts can severely degrade dose calculation accuracy in proton therapy. Prompted by the recently increased popularity of magnetic resonance imaging (MRI) in the radiation therapy clinic, we developed an MRI-based CT artifact correction method for improving the accuracy of proton range calculations. Methods and Materials: The proposed method replaces corrupted CT data by mapping CT Hounsfield units (HU number) from a nearby artifact-free slice, using a coregistered MRI. MRI and CT volumetric images were registered with use of 3-dimensional (3D) deformable image registration (DIR). The registration was fine-tuned on a slice-by-slice basis by using 2D DIR.more » Based on the intensity of paired MRI pixel values and HU from an artifact-free slice, we performed a comprehensive analysis to predict the correct HU for the corrupted region. For a proof-of-concept validation, metal artifacts were simulated on a reference data set. Proton range was calculated using reference, artifactual, and corrected images to quantify the reduction in proton range error. The correction method was applied to 4 unique clinical cases. Results: The correction method resulted in substantial artifact reduction, both quantitatively and qualitatively. On respective simulated brain and head and neck CT images, the mean error was reduced from 495 and 370 HU to 108 and 92 HU after correction. Correspondingly, the absolute mean proton range errors of 2.4 cm and 1.7 cm were reduced to less than 2 mm in both cases. Conclusions: Our MRI-based CT artifact correction method can improve CT image quality and proton range calculation accuracy for patients with severe CT artifacts.« less
NASA Astrophysics Data System (ADS)
Zhirkin, A. V.; Alekseev, P. N.; Batyaev, V. F.; Gurevich, M. I.; Dudnikov, A. A.; Kuteev, B. V.; Pavlov, K. V.; Titarenko, Yu. E.; Titarenko, A. Yu.
2017-06-01
In this report the calculation accuracy requirements of the main parameters of the fusion neutron source, and the thermonuclear blankets with a DT fusion power of more than 10 MW, are formulated. To conduct the benchmark experiments the technical documentation and calculation models were developed for two blanket micro-models: the molten salt and the heavy water solid-state blankets. The calculations of the neutron spectra, and 37 dosimetric reaction rates that are widely used for the registration of thermal, resonance and threshold (0.25-13.45 MeV) neutrons, were performed for each blanket micro-model. The MCNP code and the neutron data library ENDF/B-VII were used for the calculations. All the calculations were performed for two kinds of neutron source: source I is the fusion source, source II is the source of neutrons generated by the 7Li target irradiated by protons with energy 24.6 MeV. The spectral indexes ratios were calculated to describe the spectrum variations from different neutron sources. The obtained results demonstrate the advantage of using the fusion neutron source in future experiments.
NASA Technical Reports Server (NTRS)
Goldman, L. J.; Seasholtz, R. G.
1982-01-01
Experimental measurements of the velocity components in the blade to blade (axial tangential) plane were obtained with an axial flow turbine stator passage and were compared with calculations from three turbomachinery computer programs. The theoretical results were calculated from a quasi three dimensional inviscid code, a three dimensional inviscid code, and a three dimensional viscous code. Parameter estimation techniques and a particle dynamics calculation were used to assess the accuracy of the laser measurements, which allow a rational basis for comparison of the experimenal and theoretical results. The general agreement of the experimental data with the results from the two inviscid computer codes indicates the usefulness of these calculation procedures for turbomachinery blading. The comparison with the viscous code, while generally reasonable, was not as good as for the inviscid codes.
NASA Astrophysics Data System (ADS)
Shchinnikov, P. A.; Safronov, A. V.
2014-12-01
General principles of a procedure for matching energy balances of thermal power plants (TPPs), whose use enhances the accuracy of information-measuring systems (IMSs) during calculations of performance characteristics (PCs), are stated. To do this, there is the possibility for changing values of measured and calculated variables within intervals determined by measurement errors and regulations. An example of matching energy balances of the thermal power plants with a T-180 turbine is made. The proposed procedure allows one to reduce the divergence of balance equations by 3-4 times. It is shown also that the equipment operation mode affects the profit deficiency. Dependences for the divergence of energy balances on the deviation of input parameters and calculated data for the fuel economy before and after matching energy balances are represented.
NASA Astrophysics Data System (ADS)
Artem'ev, V. A.; Nezvanov, A. Yu.; Nesvizhevsky, V. V.
2016-01-01
We discuss properties of the interaction of slow neutrons with nano-dispersed media and their application for neutron reflectors. In order to increase the accuracy of model simulation of the interaction of neutrons with nanopowders, we perform precise quantum mechanical calculation of potential scattering of neutrons on single nanoparticles using the method of phase functions. We compare results of precise calculations with those performed within first Born approximation for nanodiamonds with the radius of 2-5 nm and for neutron energies 3 × 10-7-10-3 eV. Born approximation overestimates the probability of scattering to large angles, while the accuracy of evaluation of integral characteristics (cross sections, albedo) is acceptable. Using Monte-Carlo method, we calculate albedo of neutrons from different layers of piled up diamond nanopowder.
Accuracy of digital American Board of Orthodontics Discrepancy Index measurements.
Dragstrem, Kristina; Galang-Boquiren, Maria Therese S; Obrez, Ales; Costa Viana, Maria Grace; Grubb, John E; Kusnoto, Budi
2015-07-01
A digital analysis that is shown to be accurate will ease the demonstration of initial case complexity. To date, no literature exists on the accuracy of the digital American Board of Orthodontics Discrepancy Index (DI) calculations when applied to pretreatment digital models. Plaster models were obtained from 45 previous patients with varying degrees of malocclusion. Total DI scores and the target disorders were computed manually with a periodontal probe on the original plaster casts (gold standard) and digitally using Ortho Insight 3D (Motion View Software, Hixson, Tenn) and OrthoCAD (Cadent, Carlstadt, NJ). Intrarater and interrater reliabilities were assessed for 15 subjects using the Spearman rho correlation test. Accuracies of the DI scores and target disorders were assessed for all 45 subjects using Wilcoxon signed ranks tests. Intrarater and interrater reliabilities were high for total DI scores and most target disorders (r > 0.8). No significant difference was found between total DI score when measured with OrthoCAD compared with manual calculations. The total DI scores calculated by Ortho Insight 3D were found to be significantly greater than those by manual calculation by 2.71 points. The findings indicate that a DI calculated by Ortho Insight 3D may lead the clinician to overestimate case complexity. OrthoCAD's DI module was demonstrated to be a clinically acceptable alternative to manual calculation of the total scores. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.
Critical analysis of fragment-orbital DFT schemes for the calculation of electronic coupling values
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schober, Christoph; Reuter, Karsten; Oberhofer, Harald, E-mail: harald.oberhofer@ch.tum.de
2016-02-07
We present a critical analysis of the popular fragment-orbital density-functional theory (FO-DFT) scheme for the calculation of electronic coupling values. We discuss the characteristics of different possible formulations or “flavors” of the scheme which differ by the number of electrons in the calculation of the fragments and the construction of the Hamiltonian. In addition to two previously described variants based on neutral fragments, we present a third version taking a different route to the approximate diabatic state by explicitly considering charged fragments. In applying these FO-DFT flavors to the two molecular test sets HAB7 (electron transfer) and HAB11 (hole transfer),more » we find that our new scheme gives improved electronic couplings for HAB7 (−6.2% decrease in mean relative signed error) and greatly improved electronic couplings for HAB11 (−15.3% decrease in mean relative signed error). A systematic investigation of the influence of exact exchange on the electronic coupling values shows that the use of hybrid functionals in FO-DFT calculations improves the electronic couplings, giving values close to or even better than more sophisticated constrained DFT calculations. Comparing the accuracy and computational cost of each variant, we devise simple rules to choose the best possible flavor depending on the task. For accuracy, our new scheme with charged-fragment calculations performs best, while numerically more efficient at reasonable accuracy is the variant with neutral fragments.« less
NASA Astrophysics Data System (ADS)
Marchant, T. E.; Joshi, K. D.; Moore, C. J.
2018-03-01
Radiotherapy dose calculations based on cone-beam CT (CBCT) images can be inaccurate due to unreliable Hounsfield units (HU) in the CBCT. Deformable image registration of planning CT images to CBCT, and direct correction of CBCT image values are two methods proposed to allow heterogeneity corrected dose calculations based on CBCT. In this paper we compare the accuracy and robustness of these two approaches. CBCT images for 44 patients were used including pelvis, lung and head & neck sites. CBCT HU were corrected using a ‘shading correction’ algorithm and via deformable registration of planning CT to CBCT using either Elastix or Niftyreg. Radiotherapy dose distributions were re-calculated with heterogeneity correction based on the corrected CBCT and several relevant dose metrics for target and OAR volumes were calculated. Accuracy of CBCT based dose metrics was determined using an ‘override ratio’ method where the ratio of the dose metric to that calculated on a bulk-density assigned version of the same image is assumed to be constant for each patient, allowing comparison to the patient’s planning CT as a gold standard. Similar performance is achieved by shading corrected CBCT and both deformable registration algorithms, with mean and standard deviation of dose metric error less than 1% for all sites studied. For lung images, use of deformed CT leads to slightly larger standard deviation of dose metric error than shading corrected CBCT with more dose metric errors greater than 2% observed (7% versus 1%).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Apte, Michael G.; Apte, Joshua S.
2010-04-27
The Paharpur Business Centre and Software Technology Incubator Park (PBC) is a 7 story, 50,400 ft{sup 2} office building located near Nehru Place in New Delhi India. The occupancy of the building at full normal operations is about 500 people. The building management philosophy embodies innovation in energy efficiency while providing full service and a comfortable, safe, healthy environment to the occupants. Provision of excellent Indoor Air Quality (IAQ) is an expressed goal of the facility, and the management has gone to great lengths to achieve it. This is particularly challenging in New Delhi, where ambient urban pollution levels rankmore » among the worst on the planet. The approach to provide good IAQ in the building includes a range of technical elements: air washing and filtration of ventilation intake air from rooftop air handler, the use of an enclosed rooftop greenhouse with a high density of potted plants as a bio-filtration system, dedicated secondary HVAC/air handling units on each floor with re-circulating high efficiency filtration and UVC treatment of the heat exchanger coils, additional potted plants for bio-filtration on each floor, and a final exhaust via the restrooms located at each floor. The conditioned building exhaust air is passed through an energy recovery wheel and chemisorbent cartridge, transferring some heat to the incoming air to increase the HVAC energy efficiency. The management uses 'green' cleaning products exclusively in the building. Flooring is a combination of stone, tile and 'zero VOC' carpeting. Wood trim and finish appears to be primarily of solid sawn materials, with very little evidence of composite wood products. Furniture is likewise in large proportion constructed from solid wood materials. The overall impression is that of a very clean and well-kept facility. Surfaces are polished to a high sheen, probably with wax products. There was an odor of urinal cake in the restrooms. Smoking is not allowed in the building. The plants used in the rooftop greenhouse and on the floors were made up of a number of species selected for the following functions: daytime metabolic carbon dioxide (CO{sub 2}) absorption, nighttime metabolic CO{sub 2} absorption, and volatile organic compound (VOC) and inorganic gas absorption/removal for air cleaning. The building contains a reported 910 indoor plants. Daytime metabolic species reported by the PBC include Areca Palm, Oxycardium, Rubber Plant, and Ficus alii totaling 188 plants (21%). The single nighttime metabolic species is the Sansevieria with a total of 28 plants (3%). The 'air cleaning' plant species reported by the PBC include the Money Plant, Aglaonema, Dracaena Warneckii, Bamboo Palm, and Raphis Palm with a total of 694 plants (76%). The plants in the greenhouse (Areca Palm, Rubber Plant, Ficus alii, Bamboo Palm, and Raphis Palm) numbering 161 (18%) of those in the building are grown hydroponically, with the room air blown by fan across the plant root zones. The plants on the building floors are grown in pots and are located on floors 1-6. We conducted a one-day monitoring session in the PBC on January 1, 2010. The date of the study was based on availability of the measurement equipment that the researchers had shipped from Lawrence Berkeley National Lab in the U.S.A. The study date was not optimal because a large proportion of the regular building occupants were not present being New Year's Day. An estimated 40 people were present in the building all day during January 1. This being said, the building systems were in normal operations, including the air handlers and other HVAC components. The study was focused primarily on measurements in the Greenhouse and 3rd and 5th floor environments as well as rooftop outdoors. Measurements included a set of volatile organic compounds (VOCs) and aldehydes, with a more limited set of observations of indoor and outdoor particulate and carbon dioxide concentrations. Continuous measurements of Temperature (T) and relative humidity (RH) were made selected indoor and outdoor locations.« less
Ruangsetakit, Varee
2015-11-01
To re-examine relative accuracy of intraocular lens (IOL) power calculation of immersion ultrasound biometry (IUB) and partial coherence interferometry (PCI) based on a new approach that limits its interest on the cases in which the IUB's IOL and PCI's IOL assignments disagree. Prospective observational study of 108 eyes that underwent cataract surgeries at Taksin Hospital. Two halves ofthe randomly chosen sample eyes were implanted with the IUB- and PCI-assigned lens. Postoperative refractive errors were measured in the fifth week. More accurate calculation was based on significantly smaller mean absolute errors (MAEs) and root mean squared errors (RMSEs) away from emmetropia. The distributions of the errors were examined to ensure that the higher accuracy was significant clinically as well. The (MAEs, RMSEs) were smaller for PCI of (0.5106 diopter (D), 0.6037D) than for IUB of (0.7000D, 0.8062D). The higher accuracy was principally contributedfrom negative errors, i.e., myopia. The MAEs and RMSEs for (IUB, PCI)'s negative errors were (0.7955D, 0.5185D) and (0.8562D, 0.5853D). Their differences were significant. The 72.34% of PCI errors fell within a clinically accepted range of ± 0.50D, whereas 50% of IUB errors did. PCI's higher accuracy was significant statistically and clinically, meaning that lens implantation based on PCI's assignments could improve postoperative outcomes over those based on IUB's assignments.
The Quality and Accuracy of Mobile Apps to Prevent Driving After Drinking Alcohol
Stoyanov, Stoyan R; Gandabhai, Shailen; Baldwin, Alexander
2016-01-01
Background Driving after the consumption of alcohol represents a significant problem globally. Individual prevention countermeasures such as personalized mobile apps aimed at preventing such behavior are widespread, but there is little research on their accuracy and evidence base. There has been no known assessment investigating the quality of such apps. Objective This study aimed to determine the quality and accuracy of apps for drink driving prevention by conducting a review and evaluation of relevant mobile apps. Methods A systematic app search was conducted following PRISMA guidelines. App quality was assessed using the Mobile App Rating Scale (MARS). Apps providing blood alcohol calculators (hereafter “calculators”) were reviewed against current alcohol advice for accuracy. Results A total of 58 apps (30 iOS and 28 Android) met inclusion criteria and were included in the final analysis. Drink driving prevention apps had significantly lower engagement and overall quality scores than alcohol management apps. Most calculators provided conservative blood alcohol content (BAC) time until sober calculations. None of the apps had been evaluated to determine their efficacy in changing either drinking or driving behaviors. Conclusions This novel study demonstrates that most drink driving prevention apps are not engaging and lack accuracy. They could be improved by increasing engagement features, such as gamification. Further research should examine the context and motivations for using apps to prevent driving after drinking in at-risk populations. Development of drink driving prevention apps should incorporate evidence-based information and guidance, lacking in current apps. PMID:27502956
A Comparison of Numerical Problem Solving under Three Types of Calculation Conditions.
ERIC Educational Resources Information Center
Roberts, Dennis M.; Glynn, Shawn M.
1978-01-01
The study reported is the first in a series of investigations designed to empirically test the hypothesis that calculators reduce quantitative working time and increase computational accuracy, and to examine the relative magnitude of benefit that accompanies utilizing calculators compared to manual work. (MN)