The top view for analysis of scoliosis progression

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

De Smet, A.A.; Tarlton, M.A.; Cook, L.T.

1983-05-01

Using computerized spinal analysis, a new top view was developed that displays the spine as if the observer were above and looking down on the patient. Serial top views were obtained of 12 patients with idiopathic scoliosis. In five patients with clinically stable curves, the top views showed no change. One patient with an enlaring rib hump was seen on the top view to have progressive kyphosis but stable scoliosis. Six patients with progressive scoliosis all demonstrated collapse of the thoracic curve in the anteroposterior direction. Five of these six patients had associated lumbar curves. Three lumbar curves demonstrated collapsemore » in the anteroposterior direction similar to the collapse of the thoracic curves, and the other two curves appeared elongated in the anteroposterior direction.« less

Is the learning curve endless? One surgeon's experience with robotic prostatectomy

NASA Astrophysics Data System (ADS)

Patel, Vipul; Thaly, Rahul; Shah, Ketul

2007-02-01

Introduction: After performing 1,000 robotic prostatectomies we reflected back on our experience to determine what defined the learning curve and the essential elements that were the keys to surmounting it. Method: We retrospectively assessed our experience to attempt to define the learning curve(s), key elements of the procedure, technical refinements and changes in technology that facilitated our progress. Result: The initial learning curve to achieve basic competence and the ability to smoothly perform the procedure in less than 4 hours with acceptable outcomes was approximately 25 cases. A second learning curve was present between 75-100 cases as we approached more complicated patients. At 200 cases we were comfortably able to complete the procedure routinely in less than 2.5 hours with no specific step of the procedure hindering our progression. At 500 cases we had the introduction of new instrumentation (4th arm, biopolar Maryland, monopolar scissors) that changed our approach to the bladder neck and neurovascular bundle dissection. The most challenging part of the procedure was the bladder neck dissection. Conclusion: There is no single parameter that can be used to assess or define the learning curve. We used a combination of factors to make our subjective definition this included: operative time, smoothness of technical progression during the case along with clinical outcomes. The further our case experience progressed the more we expected of our outcomes, thus we continually modified our technique and hence embarked upon yet a new learning curve.

A prospective randomized controlled study on the treatment outcome of SpineCor brace versus rigid brace for adolescent idiopathic scoliosis with follow-up according to the SRS standardized criteria.

PubMed

Guo, Jing; Lam, Tsz Ping; Wong, Man Sang; Ng, Bobby Kin Wah; Lee, Kwong Man; Liu, King Lok; Hung, Lik Hang; Lau, Ajax Hong Yin; Sin, Sai Wing; Kwok, Wing Kwan; Yu, Fiona Wai Ping; Qiu, Yong; Cheng, Jack Chun Yiu

2014-12-01

SpineCor is a relatively innovative brace for non-operative treatment of adolescent idiopathic scoliosis (AIS). However, the effectiveness of SpineCor still remains controversial. The objective of the current study was to compare the treatment outcomes of SpineCor brace with that of rigid brace following the standardized Scoliosis Research Society (SRS) criteria on AIS brace study. Females subjects with AIS and aged 10-14 were randomly allocated into two groups undergoing treatment of SpineCor (S Group, n = 20) or rigid brace (R Group, n = 18). During SpineCor treatment, patients who had curve progression of >5° would be required to switch to rigid brace treatment. The effectiveness of the two brace treatments was assessed using the SRS standardized criteria. Before skeletal maturity, 7 (35.0%) patients in the S Group and 1 (5.6%) patient in the R Group had curve progression >5° (P = 0.026). At skeletal maturity, 5 of the 7 (71.4%) patients who failed with SpineCor bracing showed control from further progression by changing to rigid bracing. At the latest follow-up with a mean duration of 45.1 months after skeletally maturity, 29.4% of patients who were successfully treated by rigid brace showed further curve progression beyond skeletal maturity, versus 38.5% of patients in the SpineCor group (P > 0.05). For both groups, the primary curves were slightly improved at the time of brace weaning, but additionally increased at the latest follow-up, with a rate of 1.5° per year for post-maturity progression. Curve progression rate was found to be significantly higher in the SpineCor group when compared with the rigid brace group. Changing to rigid bracing could control further curve progression for majority of patients who previously failed with SpineCor bracing. For both SpineCor and rigid brace treatments, 30-40% of patients who were originally successfully treated by bracing would exhibit further curve progression beyond skeletal maturity. The post-maturity progression rate was found to be 1.5° per year in the current study, which was relatively greater than those reported before.

[Is it too late to start orthopedic treatment for idiopathic scoliosis with Risser scores of 4?].

PubMed

Avellanet, M; González Viejo, M-A; Sáenz, A; Hijós, M-E

2006-12-01

Orthopaedic treatment for idiopathic scoliosis in adolescence is indicated with a curve of > or =20 degrees and a Risser score< or =4, because progression of curve is low with Risser scores >4. We present the case of a young man with a left lumbar idiopathic scoliosis (T12-L4) with a curve of 10 degrees, which was stable from 13 years (Risser 0) to 16 years old (Risser 4). The scoliosis progressed quickly after a Risser score of 4 was achieved. The man had been wearing a lift on the left foot since he was 13, because of a leg length discrepancy, and had been under clinical and radiological monitoring. When the boy reached 17 years, the scoliosis rapidly progressed, to a curve of 22 degrees and a Risser score of >4. The scoliosis was effectively treated with a Boston brace. At 20 years, the Risser score was 5, and the left lumbar curve was 13 degrees after discontinuing the use of the brace. To our knowledge, no scientific reference indicates a time limit to orthopaedic treatment for idiopathic adolescent scoliosis. Despite the experts' recommendations, a brace might be indicated with a Risser score > or =4 to stop the progression of the curve.

Estimating Time to Event From Longitudinal Categorical Data: An Analysis of Multiple Sclerosis Progression.

PubMed

Mandel, Micha; Gauthier, Susan A; Guttmann, Charles R G; Weiner, Howard L; Betensky, Rebecca A

2007-12-01

The expanded disability status scale (EDSS) is an ordinal score that measures progression in multiple sclerosis (MS). Progression is defined as reaching EDSS of a certain level (absolute progression) or increasing of one point of EDSS (relative progression). Survival methods for time to progression are not adequate for such data since they do not exploit the EDSS level at the end of follow-up. Instead, we suggest a Markov transitional model applicable for repeated categorical or ordinal data. This approach enables derivation of covariate-specific survival curves, obtained after estimation of the regression coefficients and manipulations of the resulting transition matrix. Large sample theory and resampling methods are employed to derive pointwise confidence intervals, which perform well in simulation. Methods for generating survival curves for time to EDSS of a certain level, time to increase of EDSS of at least one point, and time to two consecutive visits with EDSS greater than three are described explicitly. The regression models described are easily implemented using standard software packages. Survival curves are obtained from the regression results using packages that support simple matrix calculation. We present and demonstrate our method on data collected at the Partners MS center in Boston, MA. We apply our approach to progression defined by time to two consecutive visits with EDSS greater than three, and calculate crude (without covariates) and covariate-specific curves.

Manipulation for the control of back pain and curve progression in patients with skeletally mature idiopathic scoliosis: two cases.

PubMed

Tarola, G A

1994-05-01

This report of two cases illustrates the potential effect of chiropractic manipulative therapy on back pain and curve progression in the at-risk, skeletally mature patient with adolescent idiopathic scoliosis. Two patients suffering from lumbar scoliosis and chronic back pain. Both had scoliosis that had progressed after skeletal maturity. Diversified type chiropractic manipulative therapy was used palliatively for back pain relief in one case, and routinely 1-2 times per month in the other case. The manipulation was applied manually, with the patients in the prone and side-posture positions. Vertebral levels manipulated were identified as fixated/dysfunctional segments based on static and/or motion palpation. They were generally applied to areas above and/or below the curve apex. When applied at the apex, cavitation was more easily achieved when the direction of thrust was into the concave side. This was also tolerated better by the patient. No attempt was made to "straighten the curve" by thrusting into the convex side. Gentle manual intersegmental mobilization, stretching and muscle massage techniques were also applied. The case treated palliatively had curve progression consistent with the literature over an 8-yr period. The case treated routinely did not. The procedure was effective in both cases for subjective relief of back pain. Diversified-type CMT has a favorable effect on acute back pain when used palliatively. The procedure may also have a favorable long term effect of preventing recurrence of back pain and on retarding curve progression when used routinely 1-2 times per month.

75 FR 71560 - Defense Federal Acquisition Regulation Supplement; Cost and Software Data Reporting System (DFARS...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-24

... DEPARTMENT OF DEFENSE Defense Acquisition Regulations System 48 CFR Parts 215, 234, 242, and 252... System (DFARS Case 2008-D027) AGENCY: Defense Acquisition Regulations System, Department of Defense (DoD... 1921-2, Progress Curve Report Comment: A respondent noted that DD Form 1921-2 Progress Curve Report...

Adolescent idiopathic scoliosis: Indications and efficacy of nonoperative treatment

PubMed Central

Canavese, Federico; Kaelin, André

2011-01-01

The strategy for the treatment of idiopathic scoliosis depends essentially upon the magnitude and pattern of the deformity, and its potential for progression. Treatment options include observation, bracing and/or surgery. During the past decade, several studies have demonstrated that the natural history of adolescent idiopathic scoliosis can be positively affected by nonoperative treatment, especially bracing. Other forms of conservative treatment, such as chiropractic or osteopathic manipulation, acupuncture, exercise or other manual treatments, or diet and nutrition, have not yet been proven to be effective in controlling spinal deformity progression, and those with a natural history that is favorable at the completion of growth. Observation is appropriate treatment for small curves, curves that are at low risk of progression, and those with a natural history that is favorable at the completion of growth. Indications for brace treatment are a growing child presenting with a curve of 25°–40° or a curve less than 25° with documented progression. Curves of 20°–25° in patients with pronounced skeletal immaturity should also be treated. The purpose of this review is to provide information about conservative treatment of adolescent idiopathic scoliosis. Indications for conservative treatment, hours daily wear and complications of brace treatment as well as brace types are discussed. PMID:21221217

Cervical Dilatation Curves of Spontaneous Deliveries in Pregnant Japanese Females

PubMed Central

Inde, Yusuke; Nakai, Akihito; Sekiguchi, Atsuko; Hayashi, Masako; Takeshita, Toshiyuki

2018-01-01

Background: Although cervical dilatation curves are crucial for appropriate management of labor progression, abnormal labor progression and obstetric interventions were included in previous and widely-used cervical dilatation curves. We aimed to describe the cervical dilatation curves of normal labor progression in pregnant Japanese females without abnormal labor progression and obstetric interventions. Methods: We completed retrospective obstetric record reviews on 3172 pregnant Japanese females (parity = 0, n = 1047; parity = 1, n = 1083; parity ≥ 2, n = 1042), aged 20 to 39 years old at delivery, with pregravid body mass indices of less than 30. All patients underwent spontaneous deliveries with term, singleton, cephalic and live newborns of appropriate-for-gestational age birthweight, without adverse neonatal outcomes. We characterized labor progression patterns by examining the relationship between elapsed times from the full dilatation and cervical dilatation stages, and labor durations by examining the distribution of time intervals from one cervical dilatation stage, to the next, and ultimately to the full dilatation. Results: Fastest cervical changes occurred at 6 cm (primiparas) and 5 cm (multiparas) of dilatation. The 95%tile of labor progression took over 3 hours to progress from 6 cm to 7 cm (primiparas), and over 2 hours to progress from 5 cm to 6 cm (multiparas). The 5%tile of traverse time to the full dilatation, during the active phase, was less than 1 hour (primiparas) and 0.5 hours (multiparas). At the end of the active phase, no deceleration phase was observed. Conclusions: Active labor may not start until 5 cm of dilatation. At the beginning of the active phase, cervical dilatation was slower than previously described. These results may reduce opportunities for obstetric interventions during labor progression. PMID:29725244

Understanding and Taking Control of Surgical Learning Curves.

PubMed

Gofton, Wade T; Papp, Steven R; Gofton, Tyson; Beaulé, Paul E

2016-01-01

As surgical techniques continue to evolve, surgeons will have to integrate new skills into their practice. A learning curve is associated with the integration of any new procedure; therefore, it is important for surgeons who are incorporating a new technique into their practice to understand what the reported learning curve might mean for them and their patients. A learning curve should not be perceived as negative because it can indicate progress; however, surgeons need to understand how to optimize the learning curve to ensure progress with minimal patient risk. It is essential for surgeons who are implementing new procedures or skills to define potential learning curves, examine how a reported learning curve may relate to an individual surgeon's in-practice learning and performance, and suggest methods in which an individual surgeon can modify his or her specific learning curve in order to optimize surgical outcomes and patient safety. A defined personal learning contract may be a practical method for surgeons to proactively manage their individual learning curve and provide evidence of their efforts to safely improve surgical practice.

Changes in the Flow-Volume Curve According to the Degree of Stenosis in Patients With Unilateral Main Bronchial Stenosis

PubMed Central

Yoo, Jung-Geun; Yi, Chin A; Lee, Kyung Soo; Jeon, Kyeongman; Um, Sang-Won; Koh, Won-Jung; Suh, Gee Young; Chung, Man Pyo; Kwon, O Jung

2015-01-01

Objectives The shape of the flow-volume (F-V) curve is known to change to showing a prominent plateau as stenosis progresses in patients with tracheal stenosis. However, no study has evaluated changes in the F-V curve according to the degree of bronchial stenosis in patients with unilateral main bronchial stenosis. Methods We performed an analysis of F-V curves in 29 patients with unilateral bronchial stenosis with the aid of a graphic digitizer between January 2005 and December 2011. Results The primary diseases causing unilateral main bronchial stenosis were endobronchial tuberculosis (86%), followed by benign bronchial tumor (10%), and carcinoid (3%). All unilateral main bronchial stenoses were classified into one of five grades (I, ≤25%; II, 26%-50%; III, 51%-75%; IV, 76%-90%; V, >90% to near-complete obstruction without ipsilateral lung collapse). A monophasic F-V curve was observed in patients with grade I stenosis and biphasic curves were observed for grade II-IV stenosis. Both monophasic (81%) and biphasic shapes (18%) were observed in grade V stenosis. After standardization of the biphasic shape of the F-V curve, the breakpoints of the biphasic curve moved in the direction of high volume (x-axis) and low flow (y-axis) according to the progression of stenosis. Conclusion In unilateral bronchial stenosis, a biphasic F-V curve appeared when bronchial stenosis was >25% and disappeared when obstruction was near complete. In addition, the breakpoint moved in the direction of high volume and low flow with the progression of stenosis. PMID:26045916

Polymorphic site index curves for white pine in the southern Appalachians

Treesearch

Donald E. Beck

1971-01-01

Site index curves are presented for natural stands of even-aged white pine in the southern Appalachians. The curves are based on measured height-growth trends in 42 stands. Shape of the height-growth curves was shown to change progressively with the level of site index, and these polymorphic trends are incorporated in the finished site-index curves. Comparison of the...

Significance of peak height velocity as a predictive factor for curve progression in patients with idiopathic scoliosis

PubMed Central

2015-01-01

Background Much attention has been paid to peak height velocity (PHV) as a possible predictor of curve progression in patients with idiopathic scoliosis (IS). The aim of this study was to analyze the relationship between the magnitude of the Cobb angle at PHV and scoliosis progression, defined as having surgery prior to skeletal maturity in female patients with IS. Methods A retrospective review identified 56 skeletally immature female IS patients who were followed until maturity. The mean age and the mean pubertal status at the initial visit were 10 years and 24 months before menarche respectively, with a follow-up period of 5 years. They were divided into two groups: non-surgery group (NS) and surgery group (S), depending on their treatment method in use at the final follow-up visit. Surgery group was defined as an ultimately having surgery due to Cobb angle greater than 45 degrees prior to skeletal maturity regardless of conservative management. Height measurements were recorded at each visit; height velocity was calculated as the height change, in cm, divided by the time interval, in years. The PHV, chronological age at PHV (APHV), height at PHV (HPHV), and final height (FH) were determined for each group. In patients with Cobb angle greater than 30 degrees, the corrected height was calculated by Kono formula and corrected height velocity values were provided. The sensitivity, specificity, and area under the curve (AUC) of the receiver-operating -characteristic (ROC) analysis were calculated to predict spinal curve progression for various Cobb-angle cutoff values at PHV. Results The corrected PHV had a mean value of 8.5 and 8.9 cm/year in the NS-group and S-group, respectively. The APHV was 11.9 and 11 years, the corrected HPHV was 152.9, and 149.3 cm, and the corrected FH was 159.9 and 159.3 cm, respectively. When a Cobb angle of 31.5 degrees was at PHV, ROC analysis revealed 78% sensitivity, 82% specificity, and an AUC of 0.93, acceptable values for curve progression in patients with IS. Conclusions These findings indicate that 31.5 degrees of spinal curvature when patients are at PHV is a significant predictive indicator for progression of the curve to a magnitude requiring surgery. We suggest that the curve-progression risk assessment in patients with IS should include PHV, along with measures of skeletal and non-skeletal maturities. PMID:25815057

Mild angle early onset idiopathic scoliosis children avoid progression under FITS method (Functional Individual Therapy of Scoliosis).

PubMed

Białek, Marianna

2015-05-01

Physiotherapy for stabilization of idiopathic scoliosis angle in growing children remains controversial. Notably, little data on effectiveness of physiotherapy in children with Early Onset Idiopathic Scoliosis (EOIS) has been published.The aim of this study was to check results of FITS physiotherapy in a group of children with EOIS.The charts of the patients archived in a prospectively collected database were retrospectively reviewed. The inclusion criteria were:diagnosis of EOIS based on spine radiography, age below 10 years, both girls and boys, Cobb angle between 118 and 308, Risser zero, FITS therapy, no other treatment (bracing), and a follow-up at least 2 years from the initiation of the treatment. The criterion for curve progression were as follows: the Cobb angle increase of 68 or more, for curve stabilization; the Cobb angle was 58 comparing to the initial radiograph,for curve correction; and the Cobb angle decrease of 68 or more at the final follow-up radiograph.There were 41 children with EOIS, 36 girls and 5 boys, mean age 7.71.3 years (range 4 to 9 years) who started FITS therapy. The curve pattern was single thoracic (5 children), single thoracolumbar (22 children) or double thoracic/thoracolumbar (14 children), totally 55 structural curvatures. The minimum follow-up was 2 years after initiation of the FITS treatment, maximum was 16 years, mean 4.8 years). At follow-up the mean age was 12.53.4 years. Out of 41 children, 10 passed pubertal growth spurt at the final follow-up and 31 were still immature and continued FITS therapy. Out of 41 children, 27 improved, 13 were stable, and one progressed. Out of 55 structural curves, 32 improved, 22 were stable and one progressed. For the 55 structural curves, the Cobb angle significantly decreased from 18.085.48 at first assessment to 12.586.38 at last evaluation,p<0.0001, paired t-test. The angle of trunk rotation decreased significantly from 4.782.98 to 3.282.58 at last evaluation, p<0.0001,paired t-test.FITS physiotherapy was effective in preventing curve progression in children with EOIS. Final postpubertal follow-up data is needed.

Fitting integrated enzyme rate equations to progress curves with the use of a weighting matrix.

PubMed Central

Franco, R; Aran, J M; Canela, E I

1991-01-01

A method is presented for fitting the pairs of values product formed-time taken from progress curves to the integrated rate equation. The procedure is applied to the estimation of the kinetic parameters of the adenosine deaminase system. Simulation studies demonstrate the capabilities of this strategy. A copy of the FORTRAN77 program used can be obtained from the authors by request. PMID:2006914

Methods of Technological Forecasting,

DTIC Science & Technology

1977-05-01

Trend Extrapolation Progress Curve Analogy Trend Correlation Substitution Analysis or Substitution Growth Curves Envelope Curve Advances in the State of...the Art Technological Mapping Contextual Mapping Matrix Input-Output Analysis Mathematical Models Simulation Models Dynamic Modelling. CHAPTER IV...Generation Interaction between Needs and Possibilities Map of the Technological Future — (‘ross- Impact Matri x Discovery Matrix Morphological Analysis

An Unified Multiscale Framework for Planar, Surface, and Curve Skeletonization.

PubMed

Jalba, Andrei C; Sobiecki, Andre; Telea, Alexandru C

2016-01-01

Computing skeletons of 2D shapes, and medial surface and curve skeletons of 3D shapes, is a challenging task. In particular, there is no unified framework that detects all types of skeletons using a single model, and also produces a multiscale representation which allows to progressively simplify, or regularize, all skeleton types. In this paper, we present such a framework. We model skeleton detection and regularization by a conservative mass transport process from a shape's boundary to its surface skeleton, next to its curve skeleton, and finally to the shape center. The resulting density field can be thresholded to obtain a multiscale representation of progressively simplified surface, or curve, skeletons. We detail a numerical implementation of our framework which is demonstrably stable and has high computational efficiency. We demonstrate our framework on several complex 2D and 3D shapes.

Association of Progression of Carotid Artery Wall Volume and Recurrent Transient Ischemic Attack or Stroke: A Magnetic Resonance Imaging Study.

PubMed

Lu, Mingming; Peng, Peng; Cui, Yuanyuan; Qiao, Huiyu; Li, Dongye; Cai, Jianming; Zhao, Xihai

2018-03-01

This study aimed to investigate the association between carotid plaque progression and subsequent recurrent events using magnetic resonance imaging. Sixty-three symptomatic patients with ipsilateral carotid atherosclerotic stenosis (30%-69% stenosis) determined by ultrasound underwent first and second carotid artery magnetic resonance imaging for carotid artery at baseline and ≥6 months after the first scan, respectively. All the patients had clinical follow-up after the second magnetic resonance scan for ≤5 years until the onset of recurrent transient ischemic attack or stroke. Presence/absence of carotid plaque compositional features, particularly intraplaque hemorrhage and fibrous cap rupture was identified. The annual progression of carotid wall volume between 2 magnetic resonance scans was measured. Univariate and multivariate Cox regression was used to calculate the hazard ratio and corresponding 95% confidence interval of carotid plaque features in discriminating recurrent events. Receiver-operating-characteristic-curve analysis was conducted to determine the area-under-the-curve of carotid plaque features in predicting recurrent events. Sixty-three patients (mean age: 66.5±10.0 years old; 54 males) were eligible for final statistics analysis. During a mean follow-up duration of 55.1±13.6 months, 14.3% of patients (n=9) experienced ipsilateral recurrent transient ischemic attack/stroke. The annual progression of carotid wall volume was significantly associated with recurrent events before (hazard ratio, 1.14 per 10 mm 3 ; 95% confidence interval, 1.02-1.27; P =0.019) and after (hazard ratio, 1.19 per 10 mm3; 95% confidence interval, 1.03-1.37; P =0.022) adjusted for confounding factors. In discriminating the recurrence of transient ischemia attack/stroke, receiver-operator curve analysis indicated that combined with annual progression of wall volume, there was a significant incremental improvement in the area-under-the-curve of intraplaque hemorrhage (area-under-the-curve: 0.69-0.81) and fibrous cap rupture (area-under-the-curve: 0.73-0.84). The annual progression of carotid wall volume is independently associated with recurrent ischemic cerebrovascular events, and this measurement has added value for intraplaque hemorrhage and fibrous cap rupture in predicting future events. © 2018 American Heart Association, Inc.

The sales learning curve.

PubMed

Leslie, Mark; Holloway, Charles A

2006-01-01

When a company launches a new product into a new market, the temptation is to immediately ramp up sales force capacity to gain customers as quickly as possible. But hiring a full sales force too early just causes the firm to burn through cash and fail to meet revenue expectations. Before it can sell an innovative product efficiently, the entire organization needs to learn how customers will acquire and use it, a process the authors call the sales learning curve. The concept of a learning curve is well understood in manufacturing. Employees transfer knowledge and experience back and forth between the production line and purchasing, manufacturing, engineering, planning, and operations. The sales learning curve unfolds similarly through the give-and-take between the company--marketing, sales, product support, and product development--and its customers. As customers adopt the product, the firm modifies both the offering and the processes associated with making and selling it. Progress along the manufacturing curve is measured by tracking cost per unit: The more a firm learns about the manufacturing process, the more efficient it becomes, and the lower the unit cost goes. Progress along the sales learning curve is measured in an analogous way: The more a company learns about the sales process, the more efficient it becomes at selling, and the higher the sales yield. As the sales yield increases, the sales learning process unfolds in three distinct phases--initiation, transition, and execution. Each phase requires a different size--and kind--of sales force and represents a different stage in a company's production, marketing, and sales strategies. Adjusting those strategies as the firm progresses along the sales learning curve allows managers to plan resource allocation more accurately, set appropriate expectations, avoid disastrous cash shortfalls, and reduce both the time and money required to turn a profit.

Evaluating the Bias of Alternative Cost Progress Models: Tests Using Aerospace Industry Acquisition Programs

DTIC Science & Technology

1992-12-01

suspect :mat, -n2 extent predict:.on cas jas ccsiziveiv crrei:=e amonc e v:arious models, :he fandom *.;aik, learn ha r ur e, i;<ea- variable and Bemis...Functions, Production Rate Adjustment Model, Learning Curve Model. Random Walk Model. Bemis Model. Evaluating Model Bias, Cost Prediction Bias. Cost...of four cost progress models--a random walk model, the tradiuonai learning curve model, a production rate model Ifixed-variable model). and a model

Pretreatment ADC histogram analysis is a predictive imaging biomarker for bevacizumab treatment but not chemotherapy in recurrent glioblastoma.

PubMed

Ellingson, B M; Sahebjam, S; Kim, H J; Pope, W B; Harris, R J; Woodworth, D C; Lai, A; Nghiemphu, P L; Mason, W P; Cloughesy, T F

2014-04-01

Pre-treatment ADC characteristics have been shown to predict response to bevacizumab in recurrent glioblastoma multiforme. However, no studies have examined whether ADC characteristics are specific to this particular treatment. The purpose of the current study was to determine whether ADC histogram analysis is a bevacizumab-specific or treatment-independent biomarker of treatment response in recurrent glioblastoma multiforme. Eighty-nine bevacizumab-treated and 43 chemotherapy-treated recurrent glioblastoma multiformes never exposed to bevacizumab were included in this study. In all patients, ADC values in contrast-enhancing ROIs from MR imaging examinations performed at the time of recurrence, immediately before commencement of treatment for recurrence, were extracted and the resulting histogram was fitted to a mixed model with a double Gaussian distribution. Mean ADC in the lower Gaussian curve was used as the primary biomarker of interest. The Cox proportional hazards model and log-rank tests were used for survival analysis. Cox multivariate regression analysis accounting for the interaction between bevacizumab- and non-bevacizumab-treated patients suggested that the ability of the lower Gaussian curve to predict survival is dependent on treatment (progression-free survival, P = .045; overall survival, P = .003). Patients with bevacizumab-treated recurrent glioblastoma multiforme with a pretreatment lower Gaussian curve > 1.2 μm(2)/ms had a significantly longer progression-free survival and overall survival compared with bevacizumab-treated patients with a lower Gaussian curve < 1.2 μm(2)/ms. No differences in progression-free survival or overall survival were observed in the chemotherapy-treated cohort. Bevacizumab-treated patients with a mean lower Gaussian curve > 1.2 μm(2)/ms had a significantly longer progression-free survival and overall survival compared with chemotherapy-treated patients. The mean lower Gaussian curve from ADC histogram analysis is a predictive imaging biomarker for bevacizumab-treated, not chemotherapy-treated, recurrent glioblastoma multiforme. Patients with recurrent glioblastoma multiforme with a mean lower Gaussian curve > 1.2 μm(2)/ms have a survival advantage when treated with bevacizumab.

Factors associated with spinal fusion after posterior fossa decompression in pediatric patients with Chiari I malformation and scoliosis.

PubMed

Mackel, Charles E; Cahill, Patrick J; Roguski, Marie; Samdani, Amer F; Sugrue, Patrick A; Kawakami, Noriaki; Sturm, Peter F; Pahys, Joshua M; Betz, Randal R; El-Hawary, Ron; Hwang, Steven W

2016-12-01

OBJECTIVE The authors performed a study to identify clinical characteristics of pediatric patients diagnosed with Chiari I malformation and scoliosis associated with a need for spinal fusion after posterior fossa decompression when managing the scoliotic curve. METHODS The authors conducted a multicenter retrospective review of 44 patients, aged 18 years or younger, diagnosed with Chiari I malformation and scoliosis who underwent posterior fossa decompression from 2000 to 2010. The outcome of interest was the need for spinal fusion after decompression. RESULTS Overall, 18 patients (40%) underwent posterior fossa decompression alone, and 26 patients (60%) required a spinal fusion after the decompression. The mean Cobb angle at presentation and the proportion of patients with curves > 35° differed between the decompression-only and fusion cohorts (30.7° ± 11.8° vs 52.1° ± 26.3°, p = 0.002; 5 of 18 vs 17 of 26, p = 0.031). An odds ratio of 1.0625 favoring a need for fusion was established for each 1° of increase in Cobb angle (p = 0.012, OR 1.0625, 95% CI 1.0135-1.1138). Among the 14 patients older than 10 years of age with a primary Cobb angle exceeding 35°, 13 (93%) ultimately required fusion. Patients with at least 1 year of follow-up whose curves progressed more 10° after decompression were younger than those without curve progression (6.1 ± 3.0 years vs 13.7 ± 3.2 years, p = 0.001, Mann-Whitney U-test). Left apical thoracic curves constituted a higher proportion of curves in the decompression-only group (8 of 16 vs 1 of 21, p = 0.002). CONCLUSIONS The need for fusion after posterior fossa decompression reflected the curve severity at clinical presentation. Patients presenting with curves measuring > 35°, as well as those greater than 10 years of age, may be at greater risk for requiring fusion after posterior fossa decompression, while patients less than 10 years of age may require routine monitoring for curve progression. Left apical thoracic curves may have a better response to Chiari malformation decompression.

Progression of trunk imbalance in adolescent idiopathic scoliosis with a thoracolumbar/lumbar curve: is it predictable at the initial visit?

PubMed

Hwang, Chang Ju; Lee, Choon Sung; Lee, Dong-Ho; Cho, Jae Hwan

2017-11-01

OBJECTIVE Progression of trunk imbalance is an important finding during follow-up of patients with adolescent idiopathic scoliosis (AIS). Nevertheless, no factors that predict progression of trunk imbalance have been identified. The purpose of this study was to identify parameters that predict progression of trunk imbalance in cases of AIS with a structural thoracolumbar/lumbar (TL/L) curve. METHODS This study included 105 patients with AIS and a structural TL/L curve who were followed up at an outpatient clinic. Patients with trunk imbalance (trunk shift ≥ 20 mm) at the initial visit were excluded. All patients were followed up for more than 2 years. Patients were divided into the following groups according to progression of trunk imbalance: 1) Group P, trunk shift ≥ 20 mm at the final visit and degree of progression ≥ 10 mm; and 2) Group NP, trunk shift < 20 mm at the final visit or degree of progression < 10 mm. Radiological parameters included Cobb angle, upper end vertebrae and lower end vertebrae (LEV), LEV tilt, disc wedge angle between LEV and LEV+1, trunk shift, apical vertebral translation, and apical vertebral rotation (AVR). Each parameter was compared between groups. Radiological parameters were assessed at every visit using whole-spine standing anteroposterior radiographs. RESULTS Among the 105 patients examined, 13 showed trunk imbalance with progression ≥ 10 mm at the final visit (Group P). Multivariate logistic regression analysis identified a lower Risser grade (p = 0.002) and a greater initial AVR (p = 0.020) as predictors of progressive trunk imbalance. A change in LEV tilt during follow-up was associated with trunk imbalance (p = 0.001). CONCLUSIONS Risser grade and AVR measured at the initial visit may predict progression of trunk imbalance. Surgeons should consider the risk of progressive trunk imbalance if patients show skeletal immaturity and a greater AVR at the initial visit.

Scoliosis-Specific exercises can reduce the progression of severe curves in adult idiopathic scoliosis: a long-term cohort study.

PubMed

Negrini, Alessandra; Negrini, Maria Gabriella; Donzelli, Sabrina; Romano, Michele; Zaina, Fabio; Negrini, Stefano

2015-01-01

Scoliosis fusion surgery is generally considered the only means to stop the progression of adult idiopathic scoliosis (ADIS), but for patients refusing surgery there is lack of evidence in favour of conservative treatment. The aim of the present study was to verify the possible effectiveness of scoliosis-specific exercises when facing ADIS progression. We designed a retrospective cohort study. We included 34 ADIS patients in treatment at our Institute (5 males and 29 females, mean age was 38.0 ± 11.0), exclusively treated with specific Scoliosis Specific SEAS exercises. SEAS exercises are scoliosis-specific exercises. In adult patients they are aimed to recover postural collapse, postural control and vertebral stability through an active self-correction. Postural integration is a key element, including the neuromotor integration of correct postures and an ergonomic education program. Therapy includes at least two weekly exercise sessions each lasting 45 min. Radiographic progression was the main outcome and it was analysed as a continuous variable. One way ANOVA and paired t-test were applied for continuous data, while chi-square test was applied for categorical data. Alpha was set at 0.05. The mean Cobb angle of the patients included into the present study, was 55.8 ± 13.2 °. Fifteen patients had previous x-rays testifying scoliosis progression: the average curve progression (worsening) was 9.8 ± 6.6 ° at a median of 25 (range 17-48) years. The remaining were characterized by more severe curves, exceeding 40 ° Cobb (mean curvature 50.9 ± 13.6) but it was not possible to prove that the curves had progressed in these cases. After an average period of 2 years of treatment (range 1-18y), 68 % of the patients experienced an improvement in their scoliosis. However in one patient (3 %) the scoliosis worsened by 5 ° in 18 years (progression rate reduced from 0.5 ° to 0.27 ° per year). Patients improved 4.6 ± 5.0 ° Cobb (P < 0.05), with no differences based on the localization of the curve, gender, age, length of treatment, Cobb degrees at the start of observation or treatment. Scoliosis Specific SEAS Exercises proved to be superior to natural history in ADIS, at least in individual cases and should be considered as a first line treatment especially in patients refusing scoliosis surgery.

Height velocity curves in female patients with idiopathic scoliosis.

PubMed

Chazono, Masaaki; Soshi, Sigeru; Kida, Yoshikuni; Hashimoto, Kurando; Inoue, Takeshi; Nakamura, Yousuke; Shinohara, Akira; Marumo, Keishi; Kono, Katsuki; Suzuki, Nobumasa

2012-01-01

Following identification of peak height velocity (PHV) by a recent study as a possible prognostic factor for curve progression in patients with idiopathic scoliosis (IS), the aim of this study was to investigate PHV curves in Japanese female patients with IS. The study subjects were 20 skeletally immature IS patients who were followed until maturity. The mean age and the mean pubertal status at the initial visit were 9.8 years and 24 months before menarche, respectively, with a follow-up period of 5.2 years. Height measurements were recorded at each visit, and HV was calculated as the change in height (cm) divided by the time interval (yr.) between visits of 6 to 12 months. The PHV, age at PHV (APHV), height at PHV (HPHV), and final height (FH) were determined. Patient HV curves were plotted using their HV data, and growth periods (GPs) were calculated from the curves. PHVs and GPs of study patients were compared to standard data from unaffected girls. The median values and interquartile ranges in PHV, APHV, HPHV, and FH were 8.5 cm/yr. (7.9-9.7), 11.8 yr. (11.2-12.1), 153.2 cm (150.1-155.8), and 160.1 cm (157.4-162.4), respectively. The median GP was 27 months. The PHV and GP values in IS female patients were higher and shorter than those in unaffected girls. These findings indicate that the patterns of height velocity curves in IS patients are different from those in unaffected girls, suggesting that curve progression in IS patients is associated with the magnitude of PHV and duration of GP. Recently, we have developed an HV reader to easily and quickly identify the present HV in patients with scoliosis, applicable for the clinical setting or school screening. We conclude that risk assessments of curve progression in patients with IS should include HV along with measures of skeletal maturity such as the Risser sign and/or digital skeletal age using hand X-rays.

Trabecular morphometry by fractal signature analysis is a novel marker of osteoarthritis progression.

PubMed

Kraus, Virginia Byers; Feng, Sheng; Wang, ShengChu; White, Scott; Ainslie, Maureen; Brett, Alan; Holmes, Anthony; Charles, H Cecil

2009-12-01

To evaluate the effectiveness of using subchondral bone texture observed on a radiograph taken at baseline to predict progression of knee osteoarthritis (OA) over a 3-year period. A total of 138 participants in the Prediction of Osteoarthritis Progression study were evaluated at baseline and after 3 years. Fractal signature analysis (FSA) of the medial subchondral tibial plateau was performed on fixed flexion radiographs of 248 nonreplaced knees, using a commercially available software tool. OA progression was defined as a change in joint space narrowing (JSN) or osteophyte formation of 1 grade according to a standardized knee atlas. Statistical analysis of fractal signatures was performed using a new model based on correlating the overall shape of a fractal dimension curve with radius. Fractal signature of the medial tibial plateau at baseline was predictive of medial knee JSN progression (area under the curve [AUC] 0.75, of a receiver operating characteristic curve) but was not predictive of osteophyte formation or progression of JSN in the lateral compartment. Traditional covariates (age, sex, body mass index, knee pain), general bone mineral content, and joint space width at baseline were no more effective than random variables for predicting OA progression (AUC 0.52-0.58). The predictive model with maximum effectiveness combined fractal signature at baseline, knee alignment, traditional covariates, and bone mineral content (AUC 0.79). We identified a prognostic marker of OA that is readily extracted from a plain radiograph using FSA. Although the method needs to be validated in a second cohort, our results indicate that the global shape approach to analyzing these data is a potentially efficient means of identifying individuals at risk of knee OA progression.

Effects of increasing left ventricular filling pressure in patients with acute myocardial infarction

PubMed Central

Russell, Richard O.; Rackley, Charles E.; Pombo, Jaoquin; Hunt, David; Potanin, Constantine; Dodge, Harold T.

1970-01-01

Left ventricular performance in 19 patients with acute myocardial infarction has been evaluated by measuring left ventricular response in terms of cardiac output, stroke volume, work, and power to progressive elevation of filling pressure accomplished by progressive expansion of blood volume with rapid infusion of low molecular weight dextran. Such infusion can elevate the cardiac output, stroke volume, work, and power and thus delineate the function of the left ventricle by Frank-Starling function curves. Left ventricular filling pressure in the range of 20-24 mm Hg was associated with the peak of the curves and when the filling pressure exceeded this range, the curves became flattened or decreased. An increase in cardiac output could be maintained for 4 or more hr. Patients with a flattened function curve had a high mortality in the ensuing 8 wk. The function curve showed improvement in myocardial function during the early convalescence. When left ventricular filling pressure is monitored directly or as pulmonary artery end-diastolic pressure, low molecular weight dextran provides a method for assessment of left ventricular function. Images PMID:5431663

Three-Dimensional Spinal Morphology Can Differentiate Between Progressive and Nonprogressive Patients With Adolescent Idiopathic Scoliosis at the Initial Presentation

PubMed Central

Nault, Marie-Lyne; Mac-Thiong, Jean-Marc; Roy-Beaudry, Marjolaine; Turgeon, Isabelle; deGuise, Jacques; Labelle, Hubert

2014-01-01

Study Design. This is a prospective case-control study. Objective. The objective of this study was to compare 3-dimensional (3D) morphological parameters of the spine at the first visit between a nonprogressive (NP) and a progressive (P) group of immature adolescent idiopathic scoliosis (AIS). Summary of Background Data. Prediction of curve progression remains challenging in AIS at the first visit. Prediction of progression is based on curve type, curve magnitude, and skeletal or chronological age. Methods. A prospective cohort of 133 AIS was followed from skeletal immaturity to maturity (mean, 37 mo). The first group was made up of patients with AIS with a minimum 6-degree progression of the major curve between the first and last follow-up (P) (n = 53) and the second group was composed of patients with NP who reached maturity with less than 6-degree progression (n = 81). Computerized measurements were taken on reconstructed 3-dimensional (3D) spine radiographs of the first visit. There were 6 categories of measurements: angle of plane of maximum curvature, Cobb angles (kyphosis, lordosis), 3D wedging (apical vertebra, apical disks), rotation (upper and lower junctional vertebra, apical vertebra, and thoracolumbar junction), torsion, and slenderness (height/width ratio). t tests were also conducted. Results. There was no statistical difference between the 2 groups for age and initial Cobb angle. P presented significant hypokyphosis, and parameters related to rotation presented significant statistical differences between NP and P (plane of maximal curvature, torsion, and apical axial rotation). Depth slenderness also presented statistical differences. Conclusion. This study confirms that even at the initial visit, 3D morphological differences exist between P and NP AIS. It supports the use of 3D reconstructions of the spine in the initial evaluation of AIS to help predict outcome. Level of Evidence: 3 PMID:24776699

Differentiating Tumor Progression from Pseudoprogression in Patients with Glioblastomas Using Diffusion Tensor Imaging and Dynamic Susceptibility Contrast MRI.

PubMed

Wang, S; Martinez-Lage, M; Sakai, Y; Chawla, S; Kim, S G; Alonso-Basanta, M; Lustig, R A; Brem, S; Mohan, S; Wolf, R L; Desai, A; Poptani, H

2016-01-01

Early assessment of treatment response is critical in patients with glioblastomas. A combination of DTI and DSC perfusion imaging parameters was evaluated to distinguish glioblastomas with true progression from mixed response and pseudoprogression. Forty-one patients with glioblastomas exhibiting enhancing lesions within 6 months after completion of chemoradiation therapy were retrospectively studied. All patients underwent surgery after MR imaging and were histologically classified as having true progression (>75% tumor), mixed response (25%-75% tumor), or pseudoprogression (<25% tumor). Mean diffusivity, fractional anisotropy, linear anisotropy coefficient, planar anisotropy coefficient, spheric anisotropy coefficient, and maximum relative cerebral blood volume values were measured from the enhancing tissue. A multivariate logistic regression analysis was used to determine the best model for classification of true progression from mixed response or pseudoprogression. Significantly elevated maximum relative cerebral blood volume, fractional anisotropy, linear anisotropy coefficient, and planar anisotropy coefficient and decreased spheric anisotropy coefficient were observed in true progression compared with pseudoprogression (P < .05). There were also significant differences in maximum relative cerebral blood volume, fractional anisotropy, planar anisotropy coefficient, and spheric anisotropy coefficient measurements between mixed response and true progression groups. The best model to distinguish true progression from non-true progression (pseudoprogression and mixed) consisted of fractional anisotropy, linear anisotropy coefficient, and maximum relative cerebral blood volume, resulting in an area under the curve of 0.905. This model also differentiated true progression from mixed response with an area under the curve of 0.901. A combination of fractional anisotropy and maximum relative cerebral blood volume differentiated pseudoprogression from nonpseudoprogression (true progression and mixed) with an area under the curve of 0.807. DTI and DSC perfusion imaging can improve accuracy in assessing treatment response and may aid in individualized treatment of patients with glioblastomas. © 2016 by American Journal of Neuroradiology.

Behavior of scoliosis during growth in children with osteogenesis imperfecta.

PubMed

Anissipour, Alireza K; Hammerberg, Kim W; Caudill, Angela; Kostiuk, Theodore; Tarima, Sergey; Zhao, Heather Shi; Krzak, Joseph J; Smith, Peter A

2014-02-05

Spinal deformities are common in patients with osteogenesis imperfecta, a heritable disorder that causes bone fragility. The purpose of this study was to describe the behavior of spinal curvature during growth in patients with osteogenesis imperfecta and establish its relationship to disease severity and medical treatment with bisphosphonates. The medical records and radiographs of 316 patients with osteogenesis imperfecta were retrospectively reviewed. The severity of osteogenesis imperfecta was classified with the modified Sillence classification. Serial curve measurements were recorded throughout the follow-up period for each patient with scoliosis. Regression analysis was used to determine the effect of disease severity (Sillence type), patient age, and bisphosphonate treatment on the progression of scoliosis as measured with the Cobb method. Of the 316 patients with osteogenesis imperfecta, 157 had associated scoliosis, a prevalence of 50%. Scoliosis prevalence (68%) and mean progression rate (6° per year) were the highest in the group of patients with the most severe osteogenesis imperfecta (modified Sillence type III). A group with intermediate osteogenesis imperfecta severity, modified Sillence type IV, demonstrated intermediate scoliosis values (54%, 4° per year). The patient group with the mildest form of osteogenesis imperfecta, modified Sillence type I, had the lowest scoliosis prevalence (39%) and rate of progression (1° per year). Early treatment-before the patient reached the age of six years-of type-III osteogenesis imperfecta with bisphosphonate therapy decreased the curve progression rate by 3.8° per year, which was a significant decrease. Bisphosphonate treatment had no demonstrated beneficial effect on curve behavior in patients with other types of osteogenesis imperfecta or in patients of older age. The prevalence of scoliosis in association with osteogenesis imperfecta is high. Progression rates of scoliosis in children with osteogenesis imperfecta are variable, depending on the Sillence type of osteogenesis imperfecta. High rates of scoliosis progression in type-III and type-IV osteogenesis imperfecta contrast with a benign course in type I. Bisphosphonate therapy initiated before the patient reaches the age of six years can modulate curve progression in type-III osteogenesis imperfecta.

Evaluating the HATCH score for predicting progression to sustained atrial fibrillation in ED patients with new atrial fibrillation.

PubMed

Barrett, Tyler W; Self, Wesley H; Wasserman, Brian S; McNaughton, Candace D; Darbar, Dawood

2013-05-01

Atrial fibrillation (AF) is often first detected in the emergency department (ED). Not all AF patients progress to sustained AF (ie, episodes lasting >7 days), which is associated with increased morbidity. The HATCH score stratifies patients with paroxysmal AF according to their risk for progression to sustained AF within 1 year. The HATCH score has previously never been tested in ED patients. We evaluated the accuracy of the HATCH score to predict progression to sustained AF within 1 year of initial AF diagnosis in the ED. We conducted a retrospective cohort study of 253 ED patients with new onset AF and known rhythm status for 1 year following the initial AF detection. The exposure variable was the HATCH score at initial ED evaluation. The primary outcome was rhythm status at 1 year following initial AF diagnosis. We constructed a receiver operating characteristic curve and calculated the area under the curve to estimate the HATCH score's accuracy of predicting progression to sustained AF. Overall, 61 (24%) of 253 of patients progressed to sustained AF within 1 year of initial detection, and the HATCH score receiver operating characteristic area under the curve was 0.62 (95% confidence interval, 0.54-0.70). Among ED patients with new onset AF, the HATCH score was a modest predictor of progression to sustained AF. Because only 2 patients had a HATCH greater than 5, this previously recommended cut-point was not useful in identifying high-risk patients in this cohort. Refinement of this decision aid is needed to improve its prognostic accuracy in the ED population. Copyright © 2013 Elsevier Inc. All rights reserved.

Outcomes of bracing in juvenile idiopathic scoliosis until skeletal maturity or surgery.

PubMed

Khoshbin, Amir; Caspi, Liora; Law, Peggy W; Donaldson, Sandra; Stephens, Derek; da Silva, Trevor; Bradley, Catharine S; Wright, James G

2015-01-01

Retrospective comparative study. To evaluate the outcome of bracing in patients with juvenile idiopathic scoliosis (JIS) at either skeletal maturity or time of scoliosis surgery. JIS is generally thought to have poor outcomes with high rates of surgical fusion. All patients with JIS between the ages of 4 and 10 years treated with a brace at the Hospital for Sick Children (SickKids) between 1989 and 2011 were eligible. Data were collected from patient health records until either 2 years after skeletal maturity or date of surgery. The average age at diagnosis of 88 patients with JIS was 8.4 ± 1.4 years, with a female to male ratio of approximately 8:1. Pretreatment, Risser score was zero for 80 patients (91%); 72 (92%) of the females were premenarche; and primary Cobb angles ranged from 20° to 71°. Of the 88 patients, 60 (68%) had used a thoracolumbosacral orthosis exclusively; 28 (32%) patients used "other braces" (Milwaukee, Charleston, or a combination of braces), with an average treatment duration of 3.6 ± 1.9 years.As per Scoliosis Research Society definitions, a "non-curve-progression" (≤5° change) group consisted of 25 (28%) patients; and a "curve-progression" group consisted of 63 (72%) patients where the curve had progressed 6° or more.Of the 88 patients, 44 (50%) underwent surgery. The operative rate was higher for patients with curves 30° or more than those with curves 20° to 29° prior to brace treatment (37/58 [64%] vs. 7/30 [23%], respectively; P = 0.001); other braces compared with thoracolumbosacral orthosis (19/28 [68%] vs. 25/60 [42%], respectively; P = 0.02); Lenke I and III curves compared with Lenke VI curves (33/54 [61%] vs. 2/14 [14%], respectively; P = 0.007).

Correlation between compliance and brace treatment in juvenile and adolescent idiopathic scoliosis: SOSORT 2014 award winner

PubMed Central

2014-01-01

Background Over the last years, evidence has accumulated in support of bracing as an effective treatment option in patients with idiopathic scoliosis. Yet, little information is available on the impact of compliance on the outcome of conservative treatment in scoliotic subjects. The aim of the present study was to prospectively evaluate the association between compliance to brace treatment and the progression of scoliotic curve in patients with idiopathic adolescent (AIS) or juvenile scoliosis (JIS). Methods Among 1.424 patients treated for idiopathic scoliosis, 645 were eligible for inclusion criteria. Three outcomes were distinguished in agreement with the SRS criteria: curve correction, curve stabilization and curve progression. Brace wearing was assessed by one orthopaedic surgeon (LA) and scored on a standardized form. Compliance to treatment was categorized as complete (brace worn as prescribed), incomplete A (brace removed for 1 month), incomplete B (brace removed for 2 months), incomplete C (brace removed during school hours), and incomplete D (brace worn overnight only). Chi square test, T test or ANOVA and ANOVA for repeated measures tests were used as statistical tests. Results The results from our study showed that at follow-up the compliance was: Complete 61.1%; Incomplete A 5.2%; Incomplete B 10.7%; Incomplete C 14.2%; Incomplete D 8.8%. Curve correction was accomplished in 301/319 of Complete, 19/27 Incomplete A, 25/56 Incomplete B, 52/74 Incomplete C, 27/46 Incomplete D. Cobb mean value was 29.8 ± 7.5 SD at beginning and 17.1 ± 10.9 SD at follow-up. Both Cobb and Perdriolle degree amelioration was significantly higher in patients with complete compliance over all other groups, both in juvenile, both in adolescent scoliosis. In the intention-to-treat analysis, the rate of surgical treatment was 2.1% among patients with definite outcome and 12.1% among those with drop-out. Treatment compliance showed significant interactions with time. Conclusion Curve progression and referral to surgery are lower in patients with high brace compliance. Bracing discontinuation up to 1 month does not impact on the treatment outcome. Conversely, wearing the brace only overnight is associated with a high rate of curve progression. PMID:24995038

Higher Flexibility and Better Immediate Spontaneous Correction May Not Gain Better Results for Nonstructural Thoracic Curve in Lenke 5C AIS Patients

PubMed Central

Zhang, Yanbin; Lin, Guanfeng; Wang, Shengru; Zhang, Jianguo; Shen, Jianxiong; Wang, Yipeng; Guo, Jianwei; Yang, Xinyu; Zhao, Lijuan

2016-01-01

Study Design. Retrospective study. Objective. To study the behavior of the unfused thoracic curve in Lenke type 5C during the follow-up and to identify risk factors for its correction loss. Summary of Background Data. Few studies have focused on the spontaneous behaviors of the unfused thoracic curve after selective thoracolumbar or lumbar fusion during the follow-up and the risk factors for spontaneous correction loss. Methods. We retrospectively reviewed 45 patients (41 females and 4 males) with AIS who underwent selective TL/L fusion from 2006 to 2012 in a single institution. The follow-up averaged 36 months (range, 24–105 months). Patients were divided into two groups. Thoracic curves in group A improved or maintained their curve magnitude after spontaneous correction, with a negative or no correction loss during the follow-up. Thoracic curves in group B deteriorated after spontaneous correction with a positive correction loss. Univariate analysis and multivariate analysis were built to identify the risk factors for correction loss of the unfused thoracic curves. Results. The minor thoracic curve was 26° preoperatively. It was corrected to 13° immediately with a spontaneous correction of 48.5%. At final follow-up it was 14° with a correction loss of 1°. Thoracic curves did not deteriorate after spontaneous correction in 23 cases in group A, while 22 cases were identified with thoracic curve progressing in group B. In multivariate analysis, two risk factors were independently associated with thoracic correction loss: higher flexibility and better immediate spontaneous correction rate of thoracic curve. Conclusion. Posterior selective TL/L fusion with pedicle screw constructs is an effective treatment for Lenke 5C AIS patients. Nonstructural thoracic curves with higher flexibility or better immediate correction are more likely to progress during the follow-up and close attentions must be paid to these patients in case of decompensation. Level of Evidence: 4 PMID:27831989

Testing the Importance of Individual Growth Curves in Predicting Performance on a High-Stakes Reading Comprehension Test in Florida. REL 2014-006

ERIC Educational Resources Information Center

Petscher, Yaacov; Kershaw, Sarah; Koon, Sharon; Foorman, Barbara R.

2014-01-01

Districts and schools use progress monitoring to assess student progress, to identify students who fail to respond to intervention, and to further adapt instruction to student needs. Researchers and practitioners often use progress monitoring data to estimate student achievement growth (slope) and evaluate changes in performance over time for…

Curve progression 25 years after bracing for adolescent idiopathic scoliosis: long term comparative results between two matched groups of 18 versus 23 hours daily bracing.

PubMed

Pellios, Stavros; Kenanidis, Eustathios; Potoupnis, Michael; Tsiridis, Eleftherios; Sayegh, Fares E; Kirkos, John; Kapetanos, George A

2016-01-01

Scoliotic curves do not necessarily stop progressing at skeletal maturity. The factors that influence curve behavior following bracing are not fully determined. Our objectives were to evaluate the loss of the scoliotic curve correction in a cohort of patients treated with bracing during adolescence and to compare the outcomes of 18 versus 23 h of bracing at a mean of 25 years post brace removal. Seventy-seven patients, who were successfully treated for Adolescent Idiopathic Scoliosis with Βoston brace, were re-evaluated 25 years after the end of their treatment. Patients were further divided in 2 matched groups; those wearing the brace for 23 h and those not wearing the brace at school-time, limiting the application of the brace to 18 h. The mean scoliotic curve was compared between groups before, during, just after bracing and 25 years post bracing. Validated in patients' native language forms of Short Form 36 and Oswestry Disability Index questionnaires were used to compare the quality of life between groups 25 years post bracing. The mean age of the cohort was 40.4 (±3.2) years. They underwent long term follow up at a mean of 25.16 (±2.69) years after brace removal. The mean cohort scoliotic curve increased by 3.9 (±6.69) at 25 years since brace removal. There was however no significant difference in the mean Cobb angle of the cohort between pre brace and long term follow up period (p = 0.307). The 18 and 23 h application groups were comparable according to demographics and several bracing and scoliotic curve parameters. There was no significant difference in the mean curve magnitude between 18 and 23 h application groups at brace removal (p = 0.512) and at 25 years follow-up (p = 0.878). There was also no significant difference in the mean score of Quality of Life questionnaires between groups at long term follow up. Scoliotic curves do not necessarily stop progressing after bracing. Bracing is effective treatment method with good long term results in appropriate patients. Since compliance was not objectively measured, we don't feel confident to give any indication about everyday dosage.

CYP2C19 progress curve analysis and mechanism-based inactivation by three methylenedioxyphenyl compounds.

PubMed

Salminen, Kaisa A; Meyer, Achim; Imming, Peter; Raunio, Hannu

2011-12-01

Several in vitro criteria were used to assess whether three methylenedioxyphenyl (MDP) compounds, the isoquinoline alkaloids bulbocapnine, canadine, and protopine, are mechanism-based inactivators of CYP2C19. The recently reported fluorometric CYP2C19 progress curve analysis approach was applied first to determine whether these alkaloids demonstrate time-dependent inhibition. In this experiment, bulbocapnine, canadine, and protopine displayed time dependence and saturation in their inactivation kinetics with K(I) and k(inact) values of 72.4 ± 14.7 μM and 0.38 ± 0.036 min(-1), 2.1 ± 0.63 μM and 0.18 ± 0.015 min(-1), and 7.1 ± 2.3 μM and 0.24 ± 0.021 min(-1), respectively. Additional studies were performed to determine whether other specific criteria for mechanism-based inactivation were fulfilled: NADPH dependence, irreversibility, and involvement of a catalytic step in the enzyme inactivation. CYP2C19 activity was not significantly restored by dialysis when it had been inactivated by the alkaloids in the presence of a NADPH-regenerating system, and a metabolic-intermediate complex-associated increase in absorbance at approximately 455 nm was observed. In conclusion, the CYP2C19 progress curve analysis method revealed time-dependent inhibition by these alkaloids, and additional experiments confirmed its quasi-irreversible nature. This study revealed that the CYP2C19 progress curve analysis method is useful for identifying novel mechanism-based inactivators and yields a wealth of information in one run. The alkaloids bulbocapnine, canadine, and protopine, present in herbal medicines, are new mechanism-based inactivators and the first MDP compounds exhibiting quasi-irreversible inactivation of CYP2C19.

Convergence properties of simple genetic algorithms

NASA Technical Reports Server (NTRS)

Bethke, A. D.; Zeigler, B. P.; Strauss, D. M.

1974-01-01

The essential parameters determining the behaviour of genetic algorithms were investigated. Computer runs were made while systematically varying the parameter values. Results based on the progress curves obtained from these runs are presented along with results based on the variability of the population as the run progresses.

Conservative management of idiopathic scoliosis--guidelines based on SOSORT 2006 Consensus.

PubMed

Kotwicki, Tomasz; Durmała, Jacek; Czaprowski, Dariusz; Głowacki, Maciej; Kołban, Maciej; Snela, Sławomir; Sliwiński, Zbigniew; Kowalski, Ireneusz M

2009-01-01

Idiopathic scoliosis, defined as a lateral curvature of the spine of above 10 degrees (Cobb angle), is seen in 2-3% of the growing age population, while curves above 20 degrees , requiring conservative treatment, are found in 0.3-0.5%. In our observation, both under-treatment of progressive curves and over-treatment of stable cases are common during conservative management of scoliosis. A model of therapeutic management is presented based on the experience of Polish clinicians specialising in the treatment of scoliosis as well as the effects of work of a panel of experts of SOSORT (Society on Scoliosis Orthopaedic and Rehabilitation Treatment). The model comprises the indications for conservative treatment according to age, curve type and size and Risser grading. The aetiology, classifications, usefulness of the Lonstein and Carlson factor of progression and other methods of determining the probability of scoliosis progression, as well as the psychological aspects of conservative management are presented. Based on the knowledge of the natural history of idiopathic scoliosis, factors of progression and on the SOSORT experts' opinion, guidelines are proposed for clinicians treating children and adolescents with idiopathic scoliosis, including the timing and course of brace treatment and the types of exercises. Uniform practical guidelines developed by experts may represent an essential step towards establishing standards of conservative scoliosis care in our country.

Autorotation

NASA Astrophysics Data System (ADS)

Bohr, Jakob; Markvorsen, Steen

2016-02-01

A continuous autorotation vector field along a framed space curve is defined, which describes the rotational progression of the frame. We obtain an exact integral for the length of the autorotation vector. This invokes the infinitesimal rotation vector of the frame progression and the unit vector field for the corresponding autorotation vector field. For closed curves we define an autorotation number whose integer value depends on the starting point of the curve. Upon curve deformations, the autorotation number is either constant, or can make a jump of (multiples of) plus-minus two, which corresponds to a change in rotation of multiples of 4π. The autorotation number is therefore not topologically conserved under all transformations. We discuss this within the context of generalised inflection points and of frame revisit points. The results may be applicable to physical systems such as polymers, proteins, and DNA. Finally, turbulence is discussed in the light of autorotation, as is the Philippine wine dance, the Dirac belt trick, and the 4π cycle of the flying snake. This paper is dedicated to Ian K Robinson on the occasion of Ian receiving the Gregori Aminoff Prize 2015.

MICA: Multiple interval-based curve alignment

NASA Astrophysics Data System (ADS)

Mann, Martin; Kahle, Hans-Peter; Beck, Matthias; Bender, Bela Johannes; Spiecker, Heinrich; Backofen, Rolf

2018-01-01

MICA enables the automatic synchronization of discrete data curves. To this end, characteristic points of the curves' shapes are identified. These landmarks are used within a heuristic curve registration approach to align profile pairs by mapping similar characteristics onto each other. In combination with a progressive alignment scheme, this enables the computation of multiple curve alignments. Multiple curve alignments are needed to derive meaningful representative consensus data of measured time or data series. MICA was already successfully applied to generate representative profiles of tree growth data based on intra-annual wood density profiles or cell formation data. The MICA package provides a command-line and graphical user interface. The R interface enables the direct embedding of multiple curve alignment computation into larger analyses pipelines. Source code, binaries and documentation are freely available at https://github.com/BackofenLab/MICA

A Progressive Damage Methodology for Residual Strength Predictions of Center-Crack Tension Composite Panels

NASA Technical Reports Server (NTRS)

Coats, Timothy William

1996-01-01

An investigation of translaminate fracture and a progressive damage methodology was conducted to evaluate and develop a residual strength prediction capability for laminated composites with through penetration notches. This is relevant to the damage tolerance of an aircraft fuselage that might suffer an in-flight accident such as an uncontained engine failure. An experimental characterization of several composite materials systems revealed an R-curve type of behavior. Fractographic examinations led to the postulate that this crack growth resistance could be due to fiber bridging, defined here as fractured fibers of one ply bridged by intact fibers of an adjacent ply. The progressive damage methodology is currently capable of predicting the initiation and growth of matrix cracks and fiber fracture. Using two difference fiber failure criteria, residual strength was predicted for different size panel widths and notch lengths. A ply discount fiber failure criterion yielded extremely conservative results while an elastic-perfectly plastic fiber failure criterion showed that the fiber bridging concept is valid for predicting residual strength for tensile dominated failure loads. Furthermore, the R-curves predicted by the model using the elastic-perfectly plastic fiber criterion compared very well with the experimental R-curves.

Testing the Importance of Individual Growth Curves in Predicting Performance on a High-Stakes Reading Comprehension Test in Florida. Summary. REL 2014-006

ERIC Educational Resources Information Center

Petscher, Yaacov; Kershaw, Sarah; Koon, Sharon; Foorman, Barbara R.

2014-01-01

Districts and schools use progress monitoring to assess student progress, to identify students who fail to respond to intervention, and to further adapt instruction to student needs. Researchers and practitioners often use progress monitoring data to estimate student achievement growth (slope) and evaluate changes in performance over time for…

Assessing Teachers' Competencies to Read and Interpret Graphs from Learning Progress Assessment: Results from Tests and Interviews

ERIC Educational Resources Information Center

Zeuch, Nina; Förster, Natalie; Souvignier, Elmar

2017-01-01

Learning progress assessment (LPA) provides formative information about effectiveness of instructional decisions. Learning curves are usually presented as graphical illustrations. However, little is known about teachers understanding and interpreting of graphically presented information. An instrument to measure competencies in reading graphs from…

Progression of scoliosis in patients with spastic quadriplegia after the insertion of an intrathecal baclofen pump.

PubMed

Ginsburg, Glen M; Lauder, Anthony J

2007-11-15

Medical and radiographic review of 19 consecutive patients with spastic quadriplegia before and after intrathecal baclofen pump insertion with special attention paid to progression of scoliosis. Many orthopedic surgeons who treat spastic quadriplegic patients have noticed a trend of marked scoliosis progression after the administration of intrathecal baclofen (ITB) via subcutaneous pump and catheter. The purpose of this study is to quantify scoliosis progression in this patient population before and after baclofen administration and compare this to published natural history data. The authors had noted rapid progression of scoliosis in spastic quadriplegic patients after intrathecal baclofen pump insertion. This had been noted at other centers, but no significant statistical analysis had been done comparing prepump to postpump scoliosis progression in these patients. To document the magnitude and rate of scoliosis progressions after the placement of an ITB pump, the charts and radiographs of 19 consecutive nonambulatory patients with spastic quadriplegia and an ITB pump were reviewed. To document the rate of scoliosis progression, each patient had at least 2 pre and 2 postpump insertion spinal radiographs made. All radiographs were made with the patients in the supine position without orthoses. A board-certified orthopedic surgeon reviewed these radiographs. Skeletal maturity was assessed using Risser grading. Catheter tip location and rate of baclofen administration were recorded. For 19 patients with complete radiographic data, average Cobb angles were 10.2 degrees before pump insertion and 25 degrees at an average of 20.9 months after pump insertion (P < 0.0001). These 19 patients had a mean rate of change in their Cobb angles of 1.825%/year before pump insertion and 10.95 degrees /year at an average of 23.9 months after pump insertion (P = 0.024). These results represent a 6-fold increase in the curve progression rate after pump insertion. There was no association between catheter tip location or rate of Baclofen infusion on curve progression. In published data, the rate of progression of scoliosis in skeletally immature nonambulatory patients with cerebral palsy was 4.5 degrees /year. In this study, the average rate of progression of the scoliosis for the immature was 9.02 degrees /year. For the skeletally mature bed-ridden patients, the worst-case natural history progression was 4.4 degrees /year. The comparable rate of change in skeletally mature (Risser 5) nonambulatory patients (n = 6) in this study was 28.4 degrees /year. This study demonstrates a significant increase in the rate of scoliotic curve progression after ITB pump placement when compared with published natural history data. The evidence of the beneficial effects of ITB on spasticity has been confirmed, and as larger, prospective randomized studies are conducted, the authors think that support for continued use of this treatment will increase. However, early bracing and spinal fusion may be warranted to prevent significant increases in spinal deformity if scoliosis is anticipated to progress more than 10 degrees /yr for patients with spastic quadriplegia and ITB pump. The authors are now performing spinal fusions for curves that exceed 40 degrees to 50 degrees in the presence of an ITB pump as recommended by previous reviews of scoliosis and accompanying quadriplegia.

Progressive early-onset scoliosis in Conradi disease: a 34-year follow-up of surgical management.

PubMed

Kabirian, Nima; Hunt, Leonel A; Ganjavian, Mohammad S; Akbarnia, Behrooz A

2013-03-01

Conradi-Hunermann syndrome (CHS) is a rare metabolic syndrome with several orthopaedic problems. Early-onset scoliosis is of great importance because of often rapidly progressive nature and high risk of postoperative complications. To report the 34-year follow-up and outcome of a patient with CHS treated with combined anterior and posterior fusion without instrumentation. All available clinical and radiographs of a female patient with CHS retrospectively reviewed. Overall health status, sagittal and coronal deformity, pulmonary function test, and outcome questionnaires were evaluated. Initial films at the age of 4 months showed a curve of 37 degrees from T6-T11 and a curve of 17 degrees from T11-L2. Thoracic kyphosis was measured at 43 degrees. Standing films at the age of 2 years and 2 months showed progression of both the curves to 50 and 66 degrees, respectively, and a significant spinal imbalance. The kyphosis also progressed to 57 degrees. She underwent a staged anterior inlay graft spinal fusion with autograft and allograft ribs from T8-L1 and posterior in situ fusion from T6-L1 with corticocancellous allograft. Solid radiographic fusion was observed 18 months after surgery. She was 36 years old at her latest follow-up, 34 years after surgery, with neutral clinical coronal and sagittal balance. No significant pain and respiratory complaint at moderate sports and normal daily life activity. "Vital capacity" and "total lung capacity" were 65% and 75%, respectively, of the normal. Thoracic curve of 35 degrees (T6-T11) and right thoracolumbar curve of 53 degrees from T11-L2 with a solid fusion fromT6-L1 with kyphosis measured over the fused area of 40 degrees were observed. Her overall mean Scoliosis Research Society-22 score was 3.68. She is an MBA graduate from a competitive school and currently works full-time. Although the treatment of early-onset scoliosis has significantly evolved over the past 3 decades, the traditional method of anterior release and fusion and staged in-situ posterior fusion posterior fusion with postoperative immobilization showed acceptable deformity correction and maintenance of the pulmonary function over the 34 years.

Functional principal component analysis of glomerular filtration rate curves after kidney transplant.

PubMed

Dong, Jianghu J; Wang, Liangliang; Gill, Jagbir; Cao, Jiguo

2017-01-01

This article is motivated by some longitudinal clinical data of kidney transplant recipients, where kidney function progression is recorded as the estimated glomerular filtration rates at multiple time points post kidney transplantation. We propose to use the functional principal component analysis method to explore the major source of variations of glomerular filtration rate curves. We find that the estimated functional principal component scores can be used to cluster glomerular filtration rate curves. Ordering functional principal component scores can detect abnormal glomerular filtration rate curves. Finally, functional principal component analysis can effectively estimate missing glomerular filtration rate values and predict future glomerular filtration rate values.

Computer-Based Radiographic Quantification of Joint Space Narrowing Progression Using Sequential Hand Radiographs: Validation Study in Rheumatoid Arthritis Patients from Multiple Institutions.

PubMed

Ichikawa, Shota; Kamishima, Tamotsu; Sutherland, Kenneth; Fukae, Jun; Katayama, Kou; Aoki, Yuko; Okubo, Takanobu; Okino, Taichi; Kaneda, Takahiko; Takagi, Satoshi; Tanimura, Kazuhide

2017-10-01

We have developed a refined computer-based method to detect joint space narrowing (JSN) progression with the joint space narrowing progression index (JSNPI) by superimposing sequential hand radiographs. The purpose of this study is to assess the validity of a computer-based method using images obtained from multiple institutions in rheumatoid arthritis (RA) patients. Sequential hand radiographs of 42 patients (37 females and 5 males) with RA from two institutions were analyzed by a computer-based method and visual scoring systems as a standard of reference. The JSNPI above the smallest detectable difference (SDD) defined JSN progression on the joint level. The sensitivity and specificity of the computer-based method for JSN progression was calculated using the SDD and a receiver operating characteristic (ROC) curve. Out of 314 metacarpophalangeal joints, 34 joints progressed based on the SDD, while 11 joints widened. Twenty-one joints progressed in the computer-based method, 11 joints in the scoring systems, and 13 joints in both methods. Based on the SDD, we found lower sensitivity and higher specificity with 54.2 and 92.8%, respectively. At the most discriminant cutoff point according to the ROC curve, the sensitivity and specificity was 70.8 and 81.7%, respectively. The proposed computer-based method provides quantitative measurement of JSN progression using sequential hand radiographs and may be a useful tool in follow-up assessment of joint damage in RA patients.

Conservative treatment of idiopathic scoliosis according to FITS concept: presentation of the method and preliminary, short term radiological and clinical results based on SOSORT and SRS criteria

PubMed Central

2011-01-01

Background Conservative scoliosis therapy according to the FITS Concept is applied as a unique treatment or in combination with corrective bracing. The aim of the study was to present author's method of diagnosis and therapy for idiopathic scoliosis FITS-Functional Individual Therapy of Scoliosis and to analyze the early results of FITS therapy in a series of consecutive patients. Methods The analysis comprised separately: (1) single structural thoracic, thoracolumbar or lumbar curves and (2) double structural scoliosis-thoracic and thoracolumbar or lumbar curves. The Cobb angle and Risser sign were analyzed at the initial stage and at the 2.8-year follow-up. The percentage of patients improved (defined as decrease of Cobb angle of more than 5 degrees), stable (+/- 5 degrees), and progressed (increase of Cobb angle of more than 5 degrees) was calculated. The clinical assessment comprised: the Angle of Trunk Rotation (ATR) initial and follow-up value, the plumb line imbalance, the scapulae level and the distance from the apical spinous process of the primary curve to the plumb line. Results In the Group A: (1) in single structural scoliosis 50,0% of patients improved, 46,2% were stable and 3,8% progressed, while (2) in double scoliosis 50,0% of patients improved, 30,8% were stable and 19,2% progressed. In the Group B: (1) in single scoliosis 20,0% of patients improved, 80,0% were stable, no patient progressed, while (2) in double scoliosis 28,1% of patients improved, 46,9% were stable and 25,0% progressed. Conclusion Best results were obtained in 10-25 degrees scoliosis which is a good indication to start therapy before more structural changes within the spine establish. PMID:22122964

Learning Curve: Charting Progress on Pesticide Use and the Healthy Schools Act.

ERIC Educational Resources Information Center

McKendry, Corina

This progress report investigated two key questions regarding the Healthy Schools Act and pesticide use in California's schools. First, has the act reduced overall pesticide use in California's largest school districts? Second, having had a year to come into compliance, are surveyed districts meeting their responsibilities? Based on a survey of…

Molecular monitoring of epithelial-to-mesenchymal transition in breast cancer cells by means of Raman spectroscopy.

PubMed

Marro, M; Nieva, C; Sanz-Pamplona, R; Sierra, A

2014-09-01

In breast cancer the presence of cells undergoing the epithelial-to-mesenchymal transition is indicative of metastasis progression. Since metabolic features of breast tumour cells are critical in cancer progression and drug resistance, we hypothesized that the lipid content of malignant cells might be a useful indirect measure of cancer progression. In this study Multivariate Curve Resolution was applied to cellular Raman spectra to assess the metabolic composition of breast cancer cells undergoing the epithelial to mesenchymal transition. Multivariate Curve Resolution analysis led to the conclusion that this transition affects the lipid profile of cells, increasing tryptophan but maintaining a low fatty acid content in comparison with highly metastatic cells. Supporting those results, a Partial Least Square-Discriminant analysis was performed to test the ability of Raman spectroscopy to discriminate the initial steps of epithelial to mesenchymal transition in breast cancer cells. We achieved a high level of sensitivity and specificity, 94% and 100%, respectively. In conclusion, Raman microspectroscopy coupled with Multivariate Curve Resolution enables deconvolution and tracking of the molecular content of cancer cells during a biochemical process, being a powerful, rapid, reagent-free and non-invasive tool for identifying metabolic features of breast cancer cell aggressiveness at first stages of malignancy. Copyright © 2014 Elsevier B.V. All rights reserved.

Evaluation of the efficiency of the Chêneau brace on scoliosis deformity : A systematic review of the literature.

PubMed

Taghi Karimi, Mohammad; Rabczuk, Timon; Kavyani, Mahsa

2018-03-01

Scoliosis is a three-dimensional deformity of the spine and rib cage. Depending on the severity of this disease, various kinds of treatment methods have been used and bracing is among the most common. One of the braces which has been used for subjects with scoliosis is the Chêneau brace. The aim of this review was to evaluate the efficiency of the Chêneau brace on the scoliosis curve progression and control based on the available literature. We conducted a Medline search via PubMed, Google Scholar, ISI Web of Sciences, Ebsco and Scopus. Keywords such as Chêneau brace, Chêneau light and CAD/CAM spinal brace were used in combination with scoliosis. The quality of the studies was evaluated by the Down and Black tool. Based on the aforementioned keywords, 55 papers were found. Finally based on the mentioned criteria 14 papers were selected for final analysis. The quality of the studies varied between scores of 13 and 25 using the Down and Black tool. The results of the selected studies confirmed that a good scoliotic curve correction can be achieved with the Chêneau brace. The Chêneau brace provides a 3-dimensional correction of the spinal deformity which not only influences the progression of scoliotic curve but also influences its natural history. It cannot be concluded that the Chêneau brace is superior to other available braces; however, it has been shown that this brace is effective to control the scoliotic curve progression especially in the lumbar and thoracolumbar regions.

Learning curve for the management of tyrosine kinase inhibitors as the first line of treatment for patients with metastatic renal cancer.

PubMed

Lendínez-Cano, G; Osman García, I; Congregado Ruiz, C B; Conde Sánchez, J M; Medina López, R A

2018-03-07

To analyse the learning curve for the management of tyrosine kinase inhibitors as the first line of treatment for patients with metastatic renal cancer. We evaluated 32 consecutive patients treated in our department for metastatic renal cancer with tyrosine kinase inhibitors (pazopanib or sunitinib) as first-line treatment between September 2012 and November 2015. We retrospectively analysed this sample. We measured the time to the withdrawal of the first-line treatment, the time to progression and overall survival using Kaplan-Meier curves. The learning curve was analysed with the cumulative sum (CUSUM) methodology. In our series, the median time to the withdrawal of the first-line treatment was 11 months (95% CI 4.9-17.1). The mean time to progression was 30.4 months (95% CI 22.7-38.1), and the mean overall survival was 34.9 months (95% CI 27.8-42). By applying the CUSUM methodology, we obtained a graph for the CUSUM value of the time to withdrawal of the first-line treatment (CUSUM TW), observing 3 well-differentiated phases: phase 1 or initial learning phase (1-15), phase 2 (16-26) in which the management of the drug progressively improved and phase 3 (27-32) of maximum experience or mastery of the management of these drugs. The number of treated patients needed to achieve the proper management of these patients was estimated at 15. Despite the limitations of the sample size and follow-up time, we estimated (in 15 patients) the number needed to reach the necessary experience in the management of these patients with tyrosine kinase inhibitors. We observed no relationship between the time to the withdrawal of the first-line treatment for any cause and progression. Copyright © 2018 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

Cobb Angle Progression in Adolescent Scoliosis Begins at the Intervertebral Disc

PubMed Central

Will, Ryan E; Stokes, Ian A; Qiu, Xing; Walker, Matthew R.; Sanders, James O

2009-01-01

Study Design Longitudinal radiographic study of patients with progressive idiopathic scoliosis. Objective To determine the relative contributions of vertebral and disc wedging to the increase in Cobb angle during 3 phases of adolescent skeletal growth and maturation. Summary of Background Data Both disc wedging and vertebral body wedging are found in progressive scoliosis, but their relative contribution to curve progression over time is unknown. Which occurs first is important for understanding how scoliosis progresses and for developing methods to halt progression. Previous studies have not properly identified maturity and provide conflicting results. Methods Eighteen girls were followed through their adolescent growth spurt with serial spine and hand skeletal age radiographs. Each Cobb angle was divided into disc wedge angles and vertebral wedge angles. The corresponding hand radiographs provided a measure of maturity level, the Digital Skeletal Age (DSA). The disc versus bone contributions to the Cobb angle were then compared during 3 growth phases: prior to the growth spurt, during the growth spurt and after the growth spurt. Significance of relative changes was assessed with the Wilcoxon two-sided mean rank test. Results Prior to the growth spurt, there was no difference in relative contributions of the disc and the bone (3° vs 0°, p=0.38) to curve progression. During the growth spurt, the mean disc component progressed significantly more than that of the vertebrae (15° vs 0°, p=0.0002). This reversed following the growth spurt with the vertebral component progressing more than the disc (10° vs 0°, p=0.01). Conclusion Adolescent idiopathic scoliosis initially increases through disc wedging during the rapid growth spurt with progressive vertebral wedging occurring later. PMID:19940737

Are there differences in the first stage of labor between Black and White women?

PubMed

Tuuli, Methodius G; Odibo, Anthony O; Caughey, Aaron B; Roehl, Kimberly; Macones, George A; Cahill, Alison G

2015-02-01

The objective of this study was to determine whether the duration and progress of the first stage of labor are different in black compared with white women. Retrospective cohort study of labor progress among consecutive black (n = 3,924) and white (n = 921) women with singleton term pregnancies (≥ 37 weeks) who completed the first stage of labor. Duration of labor and progression from 1 cm to the next was estimated using interval-censored regression. Labor duration and progress among black and white women in the entire cohort, and stratified by parity, were compared in multivariable interval-censored regression models. Repeated-measures analysis with 9th-degree polynomial modeling was used to construct average labor curves. There were no significant differences in duration of the first stage of labor in black compared with white women (median, 4-10 cm: 5.1 vs. 4.9 hours [p = 0.43] for nulliparous and 3.5 vs. 3.9 hours [p = 0.84] for multiparous women). Similarly, there were no significant differences in progression in increments of 1 cm. Average labor curves were also not significantly different. Duration and progress of the first stage of labor are identical in black and white women. This suggests similar standards may be applied in the first stage of labor. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Pre-treatment interleukin-6 levels strongly affect bone erosion progression and repair detected by magnetic resonance imaging in rheumatoid arthritis patients.

PubMed

Kondo, Yasushi; Kaneko, Yuko; Sugiura, Hiroaki; Matsumoto, Shunsuke; Nishina, Naoshi; Kuwana, Masataka; Jinzaki, Masahiro; Takeuchi, Tsutomu

2017-07-01

To examine the relationship between MRI structural damage and repair and plasma inflammatory cytokines in patients with RA. A total of 88 newly diagnosed, untreated RA patients were enrolled. Contrast MRI of the dominant hand and X-rays of the hands and feet were performed at baseline and 1 year later. MR images were evaluated using RA MRI scoring, and X-ray. Progression of bone erosion and repair were observed more frequently in MRI than in X-rays (erosion, 52% vs 26%, P < 0.001; repair, 26% vs 15%, P = 0.003, respectively). Baseline IL-6 levels and seropositivity were independent relevant factors for MRI erosion progression, with IL-6 having stronger effect than seropositivity. A receiver operating characteristic curve identified the baseline IL-6 level of 7.6 pg/ml for predicting erosion progression during 1 year, with an area under the curve of 0.82; higher IL-6 levels resulted in more erosion progression. Baseline low IL-6 was also an independent predictor for MRI erosion repair. In newly diagnosed, untreated RA patients, baseline plasma IL-6 levels are responsible for 1-year MRI bone erosion progression and repair. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Plasma copeptin level predicts acute traumatic coagulopathy and progressive hemorrhagic injury after traumatic brain injury.

PubMed

Yang, Ding-Bo; Yu, Wen-Hua; Dong, Xiao-Qiao; Du, Quan; Shen, Yong-Feng; Zhang, Zu-Yong; Zhu, Qiang; Che, Zhi-Hao; Liu, Qun-Jie; Wang, Hao; Jiang, Li; Du, Yuan-Feng

2014-08-01

Higher plasma copeptin levels correlate with poor clinical outcomes after traumatic brain injury. Nevertheless, their links with acute traumatic coagulopathy and progressive hemorrhagic injury are unknown. Therefore, we aimed to investigate the relationship between plasma copeptin levels, acute traumatic coagulopathy and progressive hemorrhagic injury in patients with severe traumatic brain injury. We prospectively studied 100 consecutive patients presenting within 6h from head trauma. Progressive hemorrhagic injury was present when the follow-up computerized tomography scan reported any increase in size or number of the hemorrhagic lesion, including newly developed ones. Acute traumatic coagulopathy was defined as an activated partial thromboplastic time greater than 40s and/or international normalized ratio greater than 1.2 and/or a platelet count less than 120×10(9)/L. We measured plasma copeptin levels on admission using an enzyme-linked immunosorbent assay in a blinded fashion. In multivariate logistic regression analysis, plasma copeptin level emerged as an independent predictor of progressive hemorrhagic injury and acute traumatic coagulopathy. Using receiver operating characteristic curves, we calculated areas under the curve for progressive hemorrhagic injury and acute traumatic coagulopathy. The predictive performance of copeptin was similar to that of Glasgow Coma Scale score. However, copeptin did not obviously improve the predictive value of Glasgow Coma Scale score. Thus, copeptin may help in the prediction of progressive hemorrhagic injury and acute traumatic coagulopathy after traumatic brain injury. Copyright © 2014 Elsevier Inc. All rights reserved.

Studies on the control of cell wall extension. Yearly progress report, September 1, 1978-August 31, 1979

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

Cleland, R. E.

Research has been centered around the question as to how plant cell enlargement is controlled and regulated at the cellular level. Progress is reported on the following projects: proton permeability of plant cuticles; the control of osmoregulation in Avena coleoptiles; an analysis of the acid-extension curves. (ACR)

The Impact of Technological Progress in the Energy Sector on Carbon Emissions: An Empirical Analysis from China

PubMed Central

Jin, Lei; Duan, Keran; Shi, Chunming; Ju, Xianwei

2017-01-01

This paper investigates the relationship between technological progress in the energy sector and carbon emissions based on the Environment Kuznets Curve (EKC) and data from China during the period of 1995–2012. Our study confirms that the situation in China conforms to the EKC hypothesis and presents the inverted U-curve relationship between per capita income and carbon emissions. Furthermore, the inflection point will be reached in at least five years. Then, we use research and development (R & D) investment in the energy industry as the quantitative indicator of its technological progress to test its impact on carbon emissions. Our results show that technological progress in the energy sector contributes to a reduction in carbon emissions with hysteresis. Furthermore, our results show that energy efficiency improvements are also helpful in reducing carbon emissions. However, climate policy and change in industrial structure increase carbon emissions to some extent. Our conclusion demonstrates that currently, China is not achieving economic growth and pollution reduction simultaneously. To further achieve the goal of carbon reduction, the government should increase investment in the energy industry research and improve energy efficiency. PMID:29207562

The Impact of Technological Progress in the Energy Sector on Carbon Emissions: An Empirical Analysis from China.

PubMed

Jin, Lei; Duan, Keran; Shi, Chunming; Ju, Xianwei

2017-12-04

This paper investigates the relationship between technological progress in the energy sector and carbon emissions based on the Environment Kuznets Curve (EKC) and data from China during the period of 1995-2012. Our study confirms that the situation in China conforms to the EKC hypothesis and presents the inverted U-curve relationship between per capita income and carbon emissions. Furthermore, the inflection point will be reached in at least five years. Then, we use research and development (R & D) investment in the energy industry as the quantitative indicator of its technological progress to test its impact on carbon emissions. Our results show that technological progress in the energy sector contributes to a reduction in carbon emissions with hysteresis. Furthermore, our results show that energy efficiency improvements are also helpful in reducing carbon emissions. However, climate policy and change in industrial structure increase carbon emissions to some extent. Our conclusion demonstrates that currently, China is not achieving economic growth and pollution reduction simultaneously. To further achieve the goal of carbon reduction, the government should increase investment in the energy industry research and improve energy efficiency.

The learning curve of laparoscopic holecystectomy in general surgery resident training: old age of the patient may be a risk factor?

PubMed

Ferrarese, Alessia; Gentile, Valentina; Bindi, Marco; Rivelli, Matteo; Cumbo, Jacopo; Solej, Mario; Enrico, Stefano; Martino, Valter

2016-01-01

A well-designed learning curve is essential for the acquisition of laparoscopic skills: but, are there risk factors that can derail the surgical method? From a review of the current literature on the learning curve in laparoscopic surgery, we identified learning curve components in video laparoscopic cholecystectomy; we suggest a learning curve model that can be applied to assess the progress of general surgical residents as they learn and master the stages of video laparoscopic cholecystectomy regardless of type of patient. Electronic databases were interrogated to better define the terms "surgeon", "specialized surgeon", and "specialist surgeon"; we surveyed the literature on surgical residency programs outside Italy to identify learning curve components, influential factors, the importance of tutoring, and the role of reference centers in residency education in surgery. From the definition of acceptable error, self-efficacy, and error classification, we devised a learning curve model that may be applied to training surgical residents in video laparoscopic cholecystectomy. Based on the criteria culled from the literature, the three surgeon categories (general, specialized, and specialist) are distinguished by years of experience, case volume, and error rate; the patients were distinguished for years and characteristics. The training model was constructed as a series of key learning steps in video laparoscopic cholecystectomy. Potential errors were identified and the difficulty of each step was graded using operation-specific characteristics. On completion of each procedure, error checklist scores on procedure-specific performance are tallied to track the learning curve and obtain performance indices of measurement that chart the trainee's progress. The concept of the learning curve in general surgery is disputed. The use of learning steps may enable the resident surgical trainee to acquire video laparoscopic cholecystectomy skills proportional to the instructor's ability, the trainee's own skills, and the safety of the surgical environment. There were no patient characteristics that can derail the methods. With this training scheme, resident trainees may be provided the opportunity to develop their intrinsic capabilities without the loss of basic technical skills.

Urinary Liver-Type Fatty Acid–Binding Protein and Progression of Diabetic Nephropathy in Type 1 Diabetes

PubMed Central

Panduru, Nicolae M.; Forsblom, Carol; Saraheimo, Markku; Thorn, Lena; Bierhaus, Angelika; Humpert, Per M.; Groop, Per-Henrik

2013-01-01

OBJECTIVE Diabetic nephropathy (DN) has mainly been considered a glomerular disease, although tubular dysfunction may also play a role. This study assessed the predictive value for progression of a tubular marker, urinary liver-type fatty acid–binding protein (L-FABP), at all stages of DN. RESEARCH DESIGN AND METHODS At baseline, 1,549 patients with type 1 diabetes had an albumin excretion rate (AER) within normal reference ranges, 334 had microalbuminuria, and 363 had macroalbuminuria. Patients were monitored for a median of 5.8 years (95% CI 5.7–5.9). In addition, 208 nondiabetic subjects were studied. L-FABP was measured by ELISA and normalized with urinary creatinine. Different Cox proportional hazard models for the progression at every stage of DN were used to evaluate the predictive value of L-FABP. The potential benefit of using L-FABP alone or together with AER was assessed by receiver operating characteristic curve analyses. RESULTS L-FABP was an independent predictor of progression at all stages of DN. As would be expected, receiver operating characteristic curves for the prediction of progression were significantly larger for AER than for L-FABP, except for patients with baseline macroalbuminuria, in whom the areas were similar. Adding L-FABP to AER in the models did not significantly improve risk prediction of progression in favor of the combination of L-FABP plus AER compared with AER alone. CONCLUSIONS L-FABP is an independent predictor of progression of DN irrespective of disease stage. L-FABP used alone or together with AER may not improve the risk prediction of DN progression in patients with type 1 diabetes, but further studies are needed in this regard. PMID:23378622

The combination of lanthanum chloride and the calcimimetic calindol delays the progression of vascular smooth muscle cells calcification

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

Ciceri, Paola; Volpi, Elisa; Brenna, Irene

2012-02-24

Highlights: Black-Right-Pointing-Pointer Lanthanum reduces the progression of high phosphate-induced calcium deposition. Black-Right-Pointing-Pointer Calcium receptor agonists and the calcimimetic calindol reduce calcium deposition. Black-Right-Pointing-Pointer Lanthanum and calindol cooperate on reducing calcium deposition. Black-Right-Pointing-Pointer Lanthanum and calindol may interact with the same receptor. -- Abstract: Phosphate (Pi)-binders are commonly used in dialysis patients to control high Pi levels, that associated with vascular calcification (VC). The aim of this study was to investigate the effects of lanthanum chloride (LaCl{sub 3}) on the progression of high Pi-induced VC, in rat vascular smooth muscle cells (VSMCs). Pi-induced Ca deposition was inhibited by LaCl{sub 3}, withmore » a maximal effect at 100 {mu}M (59.0 {+-} 2.5% inhibition). Furthermore, we studied the effects on VC of calcium sensing receptor (CaSR) agonists. Gadolinium chloride, neomycin, spermine, and the calcimimetic calindol significantly inhibited Pi-induced VC (55.9 {+-} 2.2%, 37.3 {+-} 4.7%, 30.2 {+-} 5.7%, and 63.8 {+-} 5.7%, respectively). To investigate the hypothesis that LaCl{sub 3} reduces the progression of VC by interacting with the CaSR, we performed a concentration-response curve of LaCl{sub 3} in presence of a sub-effective concentration of calindol (10 nM). Interestingly, this curve was shifted to the left (IC{sub 50} 9.6 {+-} 2.6 {mu}M), compared to the curve in the presence of LaCl{sub 3} alone (IC{sub 50} 19.0 {+-} 4.8 {mu}M). In conclusion, we demonstrated that lanthanum chloride effectively reduces the progression of high phosphate-induced vascular calcification. In addition, LaCl{sub 3} cooperates with the calcimimetic calindol in decreasing Ca deposition in this in vitro model. These results suggest the potential role of lanthanum in the treatment of VC induced by high Pi.« less

Severe progressive scoliosis in an adult female possibly secondary thoracic surgery in childhood treated with scoliosis specific Schroth physiotherapy: Case presentation.

PubMed

Lebel, Andrea; Lebel, Victoria Ashley

2016-01-01

Scoliosis is a complex three-dimensional (3D) spinal deformity. Acquired scoliosis in early childhood may progress into adulthood and pose an increased risk of health problems and reduction in quality of life. In Canada, patients with scoliosis are not referred for physiotherapeutic scoliosis-specific exercises (PSSE) despite the fact that Schroth physiotherapy, a scoliosis-specific 3D posture training and exercise program, can be effective in reducing pain and improving scoliosis curves, vital capacity, and overall quality of life in scoliosis patients. This case presentation shows that indeed adult curve progression can be stopped and even reversed with scoliosis specific Schroth physiotherapy (SSSPT) in an adult patient with scoliosis. This is a retrospective case presentation involving a 23-year-old female scoliosis patient who began an outpatient Schroth physiotherapy exercise program and was initially monitored monthly and then annually for improvement in measurements of angle of trunk rotation (ATR) and chest expansion and improvement in vital capacity measured with incentive spirometry. Photos were taken to document body image periodically throughout Schroth physiotherapy treatment. Additionally, the patient completed SRS-22 quality of life questionnaires every 2 years to evaluate daily function, pain, self-imagine, mental health, and scoliosis management satisfaction. Within one month of beginning SSSPT, the patient reported no more back pain and within 2 months, reported improved breathing. The patient also benefitted from improved chest expansion, reduced scoliosis curve angles (measured in Cobb degrees), increased vital capacity, decreased ATR, and higher SRS-22 scores. She became more active and resumed all athletic activity within 8 months of beginning Schroth physiotherapy. Adult scoliosis patients are not routinely referred for PSSE in Canada, even though Schroth physiotherapy, a form of PSSE, is shown to be effective in this case presentation. The patient in this case presentation was successfully treated with Schroth physiotherapy. Long-term comprehensive Schroth physiotherapy, to help correct and maintain proper posture in all aspects of daily living, should be part of scoliosis management for adult scoliosis patients in Canada to stop and reverse curve progression and to improve overall quality of life.

Statistical aspects of modeling the labor curve.

PubMed

Zhang, Jun; Troendle, James; Grantz, Katherine L; Reddy, Uma M

2015-06-01

In a recent review by Cohen and Friedman, several statistical questions on modeling labor curves were raised. This article illustrates that asking data to fit a preconceived model or letting a sufficiently flexible model fit observed data is the main difference in principles of statistical modeling between the original Friedman curve and our average labor curve. An evidence-based approach to construct a labor curve and establish normal values should allow the statistical model to fit observed data. In addition, the presence of the deceleration phase in the active phase of an average labor curve was questioned. Forcing a deceleration phase to be part of the labor curve may have artificially raised the speed of progression in the active phase with a particularly large impact on earlier labor between 4 and 6 cm. Finally, any labor curve is illustrative and may not be instructive in managing labor because of variations in individual labor pattern and large errors in measuring cervical dilation. With the tools commonly available, it may be more productive to establish a new partogram that takes the physiology of labor and contemporary obstetric population into account. Copyright © 2015 Elsevier Inc. All rights reserved.

Thoracic Idiopathic Scoliosis Severity Is Highly Correlated with 3D Measures of Thoracic Kyphosis.

PubMed

Sullivan, T Barrett; Reighard, Fredrick G; Osborn, Emily J; Parvaresh, Kevin C; Newton, Peter O

2017-06-07

Loss of thoracic kyphosis has been associated with thoracic idiopathic scoliosis. Modern 3-dimensional (3D) imaging systems allow more accurate characterization of the scoliotic deformity than traditional radiographs. In this study, we utilized 3D calculations to characterize the association between increasing scoliosis severity and changes in the sagittal and axial planes. Patients evaluated in a scoliosis clinic and determined to have either a normal spine or idiopathic scoliosis were included in the analysis. All underwent upright, biplanar radiography with 3D reconstructions. Two-dimensional (2D) measurements of the magnitude of the thoracic major curve and the thoracic kyphosis were recorded. Image processing and MATLAB analysis were utilized to produce a 3D calculation of thoracic kyphosis and apical vertebral axial rotation. Regression analysis was performed to determine the correlation of 2D kyphosis, 3D kyphosis, and apical axial rotation with the magnitude of the thoracic major curve. The 442 patients for whom 2D and 3D data were collected had a main thoracic curve magnitude ranging from 1° to 118°. Linear regression analysis of the 2D and 3D T5-T12 kyphosis versus main thoracic curve magnitude yielded significant models (p < 0.05). The 2D model had a minimally negative slope (-0.07), a small R value (0.02), and a poor correlation coefficient (-0.14). In contrast, the 3D model had a strongly negative slope (-0.54), a high R value (0.56), and a strong correlation coefficient (-0.75). Curve magnitude also had a strong correlation with loss of 3D T1-T12 kyphosis and increasing apical axial rotation. Segmentally calculated 3D thoracic kyphosis had a strongly negative correlation with the magnitude of the main thoracic curve. With near uniformity, 3D thoracic kyphosis progressively decreased as scoliosis magnitude increased, at a rate of more than half the increase in the main thoracic curve magnitude. Analysis confirmed a surprisingly strong correlation between scoliosis severity and loss of 3D kyphosis that was absent in the 2D analysis. A similarly strong correlation between curve magnitude and apical axial rotation was evident. These findings lend further credence to the concept that scoliosis progresses in the coronal, sagittal, and axial planes simultaneously. The findings of this study suggest that 3D assessment is critical for adequate characterization of the multiplanar deformity of idiopathic scoliosis and deformity in the sagittal plane is linked to deformity in the coronal plane. Increasing severity of coronal plane curvature is associated with a progressive loss of thoracic kyphosis that should be anticipated so that the appropriate intraoperative techniques for correction of idiopathic scoliosis can be applied in all 3 planes.

The effect of a modified Boston brace with anti-rotatory blades on the progression of curves in idiopathic scoliosis: aetiologic implications.

PubMed

Grivas, Theodoros B; Vasiliadis, Elias; Chatziargiropoulos, Theodoros; Polyzois, Vassilios D; Gatos, Konstandinos

2003-01-01

The effect of a modified Boston brace with anti-rotatory blades on idiopathic scoliotic curves, mainly right thoracic with a compensatory left lumbar, was studied. Twenty-eight scoliotic children divided into three sub-groups according to the curve type were included in the study. Cobb angle and rotation was measured on posteroanterior spinal radiographs taken during the first examination and also during the follow-up with the children in and out of the brace. Ten curves improved, 13 remained stable and 5 increased (Cobb angle change >5 degrees compared with the initial measurement). The brace treatment had more affect on the double curves, while single curves remained unaffected. Rotation remained unchanged in all curve types except in the lumbar component of double (right thoracic-left lumbar) curves. These findings indicate that in curves with a compensatory component (e.g. main thoracic with compensatory lumbar curve), a deforming rotatory force, which is blocked by the de-rotatory action of the blades of the above-modified Boston brace, is present and seems to be more active in the lumbar spine. It is hypothesized that this deforming rotatory force seems to be a major aetiological factor for double curves. In conclusion the conservative treatment using this brace is beneficially affecting the natural history of IS in children.

Calculation of the acoustic radiation force on coated spherical shells in progressive and standing plane waves.

PubMed

Mitri, F G

2006-07-01

In this paper, analytical equations are derived for the time-averaged radiation force induced by progressive and standing acoustic waves incident on elastic spherical shells covered with a layer of viscoelastic and sound-absorbing material. The fluid surrounding the shells is considered compressible and nonviscous. The incident field is assumed to be moderate so that the scattered field from the shells is taken to linear approximation. The analytical results are illustrated by means of a numerical example in which the radiation force function curves are displayed, with particular emphasis on the coating thickness and the content of the hollow region of the shells. The fluid-loading on the radiation force function curves is analysed as well. This study attempts to generalize the various treatments of radiation force due to both progressive and standing waves on spherically-shaped structures immersed in ideal fluids. The results show that various ways can be effectively used for damping resonance peaks, such as by changing the fluid in the interior hollow region of the shells or by changing the coating thickness.

Progress report. Task 1 - quaternary tectonics, 1 October 1991--30 September 1992

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

NONE

1992-09-30

Progress is reported on a study concerned with the quaternary tectonics of Yucca Mountain, the proposed site for an underground disposal facility for high-level radioactive wastes. Refinement and revision of crater Flat Quaternary stratigraphy continued and consisted of several activities: revision of rock varnish cation leaching curve; sample comparison of RV manganese;,iron microlaminations;and correlation of Crater Flat allostratigraphic units with regional chronologies.

Scoliosis in Patients with Severe Cerebral Palsy: Three Different Courses in Adolescents.

PubMed

Oda, Yoshiaki; Takigawa, Tomoyuki; Sugimoto, Yoshihisa; Tanaka, Masato; Akazawa, Hirofumi; Ozaki, Toshifumi

2017-04-01

Patients with cerebral palsy (CP) frequently present with scoliosis; however, the pattern of curve progression is difficult to predict. We aimed to clarify the natural course of the progression of scoliosis and to identify scoliosis predictors. This was a retrospective, single-center, observational study. Total of 92 CP patients from Asahikawasou Ryouiku Iryou Center in Okayama, Japan were retrospectively analyzed. Cobb angle, presence of hip dislocation and pelvic obliquity, and Gross Motor Function Classification System (GMFCS) were investigated. Severe CP was defined as GMFCS level IV or V. The mean observation period was 10.7 years. Thirtyfour severe CP patients presented with scoliosis and were divided into 3 groups based on their clinical courses: severe, moderate and mild. The mean Cobb angles at the final follow-up were 129°, 53°, and 13° in the severe, moderate, and mild groups, respectively. The average progressions from 18 to 25 years were 2.7°/year, 0.7°/year, and 0.1°/year in the severe, moderate, and mild curve groups, respectively. We observed the natural course of scoliosis and identified 3 courses based on the Cobb angle at 15 and 18 years of age. This method of classification may help clinicians predict the patients' disease progression.

Progressive disease in glioblastoma: Benefits and limitations of semi-automated volumetry

PubMed Central

Alber, Georgina; Bette, Stefanie; Kaesmacher, Johannes; Boeckh-Behrens, Tobias; Gempt, Jens; Ringel, Florian; Specht, Hanno M.; Meyer, Bernhard; Zimmer, Claus

2017-01-01

Purpose Unambiguous evaluation of glioblastoma (GB) progression is crucial, both for clinical trials as well as day by day routine management of GB patients. 3D-volumetry in the follow-up of GB provides quantitative data on tumor extent and growth, and therefore has the potential to facilitate objective disease assessment. The present study investigated the utility of absolute changes in volume (delta) or regional, segmentation-based subtractions for detecting disease progression in longitudinal MRI follow-ups. Methods 165 high resolution 3-Tesla MRIs of 30 GB patients (23m, mean age 60.2y) were retrospectively included in this single center study. Contrast enhancement (CV) and tumor-related signal alterations in FLAIR images (FV) were semi-automatically segmented. Delta volume (dCV, dFV) and regional subtractions (sCV, sFV) were calculated. Disease progression was classified for every follow-up according to histopathologic results, decisions of the local multidisciplinary CNS tumor board and a consensus rating of the neuro-radiologic report. Results A generalized logistic mixed model for disease progression (yes / no) with dCV, dFV, sCV and sFV as input variables revealed that only dCV was significantly associated with prediction of disease progression (P = .005). Delta volume had a better accuracy than regional, segmentation-based subtractions (79% versus 72%) and a higher area under the curve by trend in ROC curves (.83 versus .75). Conclusion Absolute volume changes of the contrast enhancing tumor part were the most accurate volumetric determinant to detect progressive disease in assessment of GB and outweighed FLAIR changes as well as regional, segmentation-based image subtractions. This parameter might be useful in upcoming objective response criteria for glioblastoma. PMID:28245291

Exponential Decay Nonlinear Regression Analysis of Patient Survival Curves: Preliminary Assessment in Non-Small Cell Lung Cancer

PubMed Central

Stewart, David J.; Behrens, Carmen; Roth, Jack; Wistuba, Ignacio I.

2010-01-01

Background For processes that follow first order kinetics, exponential decay nonlinear regression analysis (EDNRA) may delineate curve characteristics and suggest processes affecting curve shape. We conducted a preliminary feasibility assessment of EDNRA of patient survival curves. Methods EDNRA was performed on Kaplan-Meier overall survival (OS) and time-to-relapse (TTR) curves for 323 patients with resected NSCLC and on OS and progression-free survival (PFS) curves from selected publications. Results and Conclusions In our resected patients, TTR curves were triphasic with a “cured” fraction of 60.7% (half-life [t1/2] >100,000 months), a rapidly-relapsing group (7.4%, t1/2=5.9 months) and a slowly-relapsing group (31.9%, t1/2=23.6 months). OS was uniphasic (t1/2=74.3 months), suggesting an impact of co-morbidities; hence, tumor molecular characteristics would more likely predict TTR than OS. Of 172 published curves analyzed, 72 (42%) were uniphasic, 92 (53%) were biphasic, 8 (5%) were triphasic. With first-line chemotherapy in advanced NSCLC, 87.5% of curves from 2-3 drug regimens were uniphasic vs only 20% of those with best supportive care or 1 drug (p<0.001). 54% of curves from 2-3 drug regimens had convex rapid-decay phases vs 0% with fewer agents (p<0.001). Curve convexities suggest that discontinuing chemotherapy after 3-6 cycles “synchronizes” patient progression and death. With postoperative adjuvant chemotherapy, the PFS rapid-decay phase accounted for a smaller proportion of the population than in controls (p=0.02) with no significant difference in rapid-decay t1/2, suggesting adjuvant chemotherapy may move a subpopulation of patients with sensitive tumors from the relapsing group to the cured group, with minimal impact on time to relapse for a larger group of patients with resistant tumors. In untreated patients, the proportion of patients in the rapid-decay phase increased (p=0.04) while rapid-decay t1/2 decreased (p=0.0004) with increasing stage, suggesting that higher stage may be associated with tumor cells that both grow more rapidly and have a higher probability of surviving metastatic processes than in early stage tumors. This preliminary assessment of EDNRA suggests that it may be worth exploring this approach further using more sophisticated, statistically rigorous nonlinear modelling approaches. Using such approaches to supplement standard survival analyses could suggest or support specific testable hypotheses. PMID:20627364

Do adolescents with idiopathic scoliosis have body schema disorders? A cross-sectional study.

PubMed

Picelli, Alessandro; Negrini, Stefano; Zenorini, Andrea; Iosa, Marco; Paolucci, Stefano; Smania, Nicola

2016-01-01

To date etiology of adolescent idiopathic scoliosis appears complex and still remains unclear. A distorted body schema has been proposed to be a part of a sequence of pathological events in the development of adolescent idiopathic scoliosis. To investigate the awareness of trunk misalignment in adolescents with idiopathic scoliosis. Information about 44 adolescents with idiopathic scoliosis was collected as follows: age; sex; handedness; family history of scoliosis; back pain; sport practice; shoulder and waist line symmetry; leg length; dorsal kyphosis; back hump; rehabilitation; scoliotic curve; Risser sign. We evaluated awareness of trunk misalignment with a graphic table displaying pictures of progressively increasing scoliotic curves. Patients were asked to indicate which picture corresponded to their perceived own spinal alignment. Patients with thoracolumbar scoliosis overestimated their actual thoracic spine curve. Patients with thoracic-thoracolumbar scoliosis underestimated their actual thoracolumbar spine curve and overestimated their actual lumbar spine curve. Scoliotic curve > 15°, double curve, younger age, back pain, family history of scoliosis and lower Risser score related with a misperception of trunk alignment. Our results support the hypothesis that adolescents with idiopathic scoliosis have an altered corporeal awareness of their trunk alignment.

Effectiveness of Treatment of Idiopathic Scoliosis by SpineCor Dynamic Bracing with Special Physiotherapy Programme in SpineCor System.

PubMed

Rożek, Karina; Potaczek, Tomasz; Zarzycka, Maja; Lipik, Ewa; Jasiewicz, Barbara

2016-10-28

The SpineCor dynamic brace for the treatment of idiopathic scoliosis is designed to maintain the correct position of the spine and a new movement strategy for 20 hours per day. The SpineCor exercise system intensifies and complements the brace treatment. This study evaluated the effectiveness of a comprehensive treatment of idiopathic scoliosis involving the SpineCor system. The study assessed a group of 40 patients (38 girls and 2 boys) with idiopathic scoliosis treated with the SpineCor brace. The average age at beginning of treatment was 13.1 yrs (10-15). Minimum treatment time was 18 months. 28 participants met the SRS criteria. Angles of the curve before and after bracing based on imaging studies were measured at the beginning and end of the treatment, analyzed and compared. Rehabilitation focused on teaching active corrective movement throughout the brace treatment. A control group was formed of 33 patients, including 21 meeting the SRS criteria, who used the SpineCor dynamic brace but did not participate in the associated exercise programme. Among patients from the exercise group who met the SRS criteria, 25% demonstrated reduced curve angles, 35.7% demonstrated curve progression and 39.3% showed stabilization (no change). Among patients meeting the SRS criteria from the control group, a decrease in curve angle was observed in 14.3% of the patients, curve progression in 57.1% and stabilization in 28.6%. 1. The addition of a dedicated physiotherapy programme to SpineCor dynamic bracing improves the chances of obtaining a positive outcome. 2. It is necessary to further analyse the course of the comprehensive treatment, also with regard to other types of braces and kinesiotherapy programmes.

Vertebral Body Stapling versus Bracing for Patients with High-Risk Moderate Idiopathic Scoliosis

PubMed Central

Cuddihy, Laury; Danielsson, Aina J.; Cahill, Patrick J.; Samdani, Amer F.; Grewal, Harsh; Richmond, John M.; Mulcahey, M. J.; Gaughan, John P.; Antonacci, M. Darryl; Betz, Randal R.

2015-01-01

Purpose. We report a comparison study of vertebral body stapling (VBS) versus a matched bracing cohort for immature patients with moderate (25 to 44°) idiopathic scoliosis (IS). Methods. 42 of 49 consecutive patients (86%) with IS were treated with VBS and followed for a minimum of 2 years. They were compared to 121 braced patients meeting identical inclusion criteria. 52 patients (66 curves) were matched according to age at start of treatment (10.6 years versus 11.1 years, resp. [P = 0.07]) and gender. Results. For thoracic curves 25–34°, VBS had a success rate (defined as curve progression <10°) of 81% versus 61% for bracing (P = 0.16). In thoracic curves 35–44°, VBS and bracing both had a poor success rate. For lumbar curves, success rates were similar in both groups for curves measuring 25–34°. Conclusion. In this comparison of two cohorts of patients with high-risk (Risser 0-1) moderate IS (25–44°), in smaller thoracic curves (25–34°) VBS provided better results as a clinical trend as compared to bracing. VBS was found not to be effective for thoracic curves ≥35°. For lumbar curves measuring 25–34°, results appear to be similar for both VBS and bracing, at 80% success. PMID:26618169

Age of onset of myopia predicts risk of high myopia in later childhood in myopic Singapore children.

PubMed

Chua, Sharon Y L; Sabanayagam, Charumathi; Cheung, Yin-Bun; Chia, Audrey; Valenzuela, Robert K; Tan, Donald; Wong, Tien-Yin; Cheng, Ching-Yu; Saw, Seang-Mei

2016-07-01

To investigate the effect of age of myopia onset on the severity of myopia later in life among myopic children. In this prospective study, school children aged 7-9 years from the Singapore Cohort Of the Risk factors for Myopia (SCORM) were followed up till 11 years (n = 928). Age of myopia onset was defined either through questionnaire at baseline (age 7-9 years) or subsequent annual follow-up visits. Age of onset of myopia was a surrogate indicator of duration of myopia progression till age 11 years. Cycloplegic refraction and axial length were measured at every annual eye examination. High myopia was defined as spherical equivalent of ≤-5.0 D. A questionnaire determined the other risk factors. In multivariable regression models, younger age of myopia onset (per year decrease) or longer duration of myopia progression was associated with high myopia (odds ratio (OR) = 2.86; 95% CI: 2.39 to 3.43), more myopic spherical equivalent (regression coefficient (β) = -0.86 D; 95% CI: -0.93 to -0.80) and longer axial length (β = 0.28 mm; 95% CI: 0.24 to 0.32) at aged 11 years, after adjusting for gender, race, school, books per week and parental myopia. In Receiver Operating Curve (ROC) analyses, age of myopia onset alone predicted high myopia by 85% (area under the curve = 0.85), while the addition of other factors including gender, race, school, books per week and parental myopia only marginally improved this prediction (area under the curve = 0.87). Age of myopia onset or duration of myopia progression was the most important predictor of high myopia in later childhood in myopic children. Future trials to retard the progression of myopia to high myopia could focus on children with younger age of myopia onset or with longer duration of myopia progression. © 2016 The Authors Ophthalmic & Physiological Optics © 2016 The College of Optometrists.

Congenital unilateral absence of the upper extremity may give rise to a specific kind of thoracolumbar curve.

PubMed

Olgun, Z Deniz; Demirkiran, Gokhan; Polly, David; Yazici, Muharrem

2018-03-01

There is an increased incidence of scoliosis in patients with congenital malformations of the upper extremity even in the absence of overt vertebral abnormalities. In this case series, we summarize the curve characteristics of four patients presenting to two spine surgery clinics with unilateral amelia or phocomelia and a progressive scoliotic curve with the apex on the side of deficiency. All patients required orthopedic intervention for their curves. Amelia and phocomelia are severe congenital malformations of the upper limb affecting trunk balance and, conceivably, causing scoliosis with the absence of counterbalancing weight on the affected side. The combination of upper limb absence and same-sided scoliosis in these patients may provide a clue of the mechanical factors causing scoliosis in other disorders. In this article, we attempt to define this exceptional deformity, theorize on its etiology, and draw attention to this particular combination of problems. Case series; Level IV.

18F-Fluorodeoxyglucose PET/CT and dynamic contrast-enhanced MRI as imaging biomarkers in malignant pleural mesothelioma.

PubMed

Hall, David O; Hooper, Clare E; Searle, Julie; Darby, Michael; White, Paul; Harvey, John E; Braybrooke, Jeremy P; Maskell, Nick A; Masani, Vidan; Lyburn, Iain D

2018-02-01

The purpose of this study was to compare the use of fluorine-18-fluorodeoxyglucose (F-FDG) PET with computed tomography (CT) and dynamic contrast-enhanced (DCE) MRI to predict prognosis and monitor treatment in malignant pleural mesothelioma. F-FDG PET/CT and DCE-MRI studies carried out as part of the South West Area Mesothelioma Pemetrexed trial were used. F-FDG PET/CT and DCE-MRI studies were carried out before treatment, and after two cycles of chemotherapy, on patients treated with pemetrexed and cisplatin. A total of 73 patients were recruited, of whom 65 had PET/CT and DCE-MRI scans. Baseline measurements from F-FDG PET/CT (maximum standardized uptake value, metabolic tumour volume and total lesion glycolysis) and DCE-MRI (integrated area under the first 90s of the curve and washout slope) were compared with overall survival (OS) using Kaplan-Meier and Cox regression analyses, and changes in imaging measurements were compared with disease progression. PET/CT and DCE-MRI measurements were not correlated with each other. Maximum standardized uptake value, metabolic tumour volume and total lesion glycolysis were significantly related to OS with Cox regression analysis and Kaplan-Meir analysis, and DCE-MRI washout curve shape was significantly related to OS. DCE-MRI curve shape can be combined with F-FDG PET/CT to give additional prognostic information. Changes in measurements were not related to progression-free survival. F-FDG PET/CT and DCE-MRI give prognostic information in malignant pleural mesothelioma. Neither PET/CT nor DCE-MRI is useful for monitoring disease progression.

Early Cerebral Blood Volume Changes Predict Progression After Convection-Enhanced Delivery of Topotecan for Recurrent Malignant Glioma.

PubMed

Surapaneni, Krishna; Kennedy, Benjamin C; Yanagihara, Ted K; DeLaPaz, Robert; Bruce, Jeffrey N

2015-07-01

To assess whether early changes in enhancing tumor volume (eTV) and relative cerebral blood volume (rCBV) 1 month after convection-enhanced delivery of topotecan in patients with recurrent malignant glioma correlated with 6-month disease progression status. Sixteen patients were enrolled in a Phase Ib trial of convection-enhanced delivery of topotecan for recurrent malignant glioma. Each patient was evaluated with serial follow-up magnetic resonance imaging at baseline and at 4- to 8-week intervals. Changes at 1 month compared with baseline in eTV and rCBV were evaluated as potential predictors of 6-month progression status, classified as either progressive disease or nonprogressive disease. Relationships between percent changes in eTV and rCBV at 1 month with the probability of progressive disease at 6 months were estimated by the use of logistic regression analysis. Receiver operating characteristic curves for varying percent change thresholds in eTV and rCBV were evaluated by the use of 6-month progressive disease as the reference. There was a significant difference in the percent change in rCBV at 1 month in patients with progressive disease compared with those with nonprogressive disease at 6 months (+12% vs. -29%, P = 0.02). Logistic regression analysis demonstrated on average that a 10% increase in rCBV at 1 month after convection-enhanced delivery of topotecan was associated with 1.7 times the odds of developing progressive disease at 6 months (95% confidence interval [CI] 1.0-2.9 P = 0.05). Receiver operating characteristic analysis for determining progressive disease at 6 months showed a greater area under the curve with rCBV (0.867; 95% CI 0.66-1.00) than with change in enhancing tumor volume (0.767; 95% CI 0.51-1.00). In this selected population of patients with recurrent malignant glioma treated with convection-enhanced delivery of topotecan, early changes in rCBV at 4 weeks after therapy may help predict progression status at 6 months. Copyright © 2015 Elsevier Inc. All rights reserved.

Filtering data from the collaborative initial glaucoma treatment study for improved identification of glaucoma progression.

PubMed

Schell, Greggory J; Lavieri, Mariel S; Stein, Joshua D; Musch, David C

2013-12-21

Open-angle glaucoma (OAG) is a prevalent, degenerate ocular disease which can lead to blindness without proper clinical management. The tests used to assess disease progression are susceptible to process and measurement noise. The aim of this study was to develop a methodology which accounts for the inherent noise in the data and improve significant disease progression identification. Longitudinal observations from the Collaborative Initial Glaucoma Treatment Study (CIGTS) were used to parameterize and validate a Kalman filter model and logistic regression function. The Kalman filter estimates the true value of biomarkers associated with OAG and forecasts future values of these variables. We develop two logistic regression models via generalized estimating equations (GEE) for calculating the probability of experiencing significant OAG progression: one model based on the raw measurements from CIGTS and another model based on the Kalman filter estimates of the CIGTS data. Receiver operating characteristic (ROC) curves and associated area under the ROC curve (AUC) estimates are calculated using cross-fold validation. The logistic regression model developed using Kalman filter estimates as data input achieves higher sensitivity and specificity than the model developed using raw measurements. The mean AUC for the Kalman filter-based model is 0.961 while the mean AUC for the raw measurements model is 0.889. Hence, using the probability function generated via Kalman filter estimates and GEE for logistic regression, we are able to more accurately classify patients and instances as experiencing significant OAG progression. A Kalman filter approach for estimating the true value of OAG biomarkers resulted in data input which improved the accuracy of a logistic regression classification model compared to a model using raw measurements as input. This methodology accounts for process and measurement noise to enable improved discrimination between progression and nonprogression in chronic diseases.

Enhancements of Bayesian Blocks; Application to Large Light Curve Databases

NASA Technical Reports Server (NTRS)

Scargle, Jeff

2015-01-01

Bayesian Blocks are optimal piecewise linear representations (step function fits) of light-curves. The simple algorithm implementing this idea, using dynamic programming, has been extended to include more data modes and fitness metrics, multivariate analysis, and data on the circle (Studies in Astronomical Time Series Analysis. VI. Bayesian Block Representations, Scargle, Norris, Jackson and Chiang 2013, ApJ, 764, 167), as well as new results on background subtraction and refinement of the procedure for precise timing of transient events in sparse data. Example demonstrations will include exploratory analysis of the Kepler light curve archive in a search for "star-tickling" signals from extraterrestrial civilizations. (The Cepheid Galactic Internet, Learned, Kudritzki, Pakvasa1, and Zee, 2008, arXiv: 0809.0339; Walkowicz et al., in progress).

Progress in Energy Storage Technologies: Models and Methods for Policy Analysis

NASA Astrophysics Data System (ADS)

Matteson, Schuyler W.

Climate change and other sustainability challenges have led to the development of new technologies that increase energy efficiency and reduce the utilization of finite resources. To promote the adoption of technologies with social benefits, governments often enact policies that provide financial incentives at the point of purchase. In their current form, these subsidies have the potential to increase the diffusion of emerging technologies; however, accounting for technological progress can improve program success while decreasing net public investment. This research develops novel methods using experience curves for the development of more efficient subsidy policies. By providing case studies in the field of automotive energy storage technologies, this dissertation also applies the methods to show the impacts of incorporating technological progress into energy policies. Specific findings include learning-dependent tapering subsidies for electric vehicles based on the lithium-ion battery experience curve, the effects of residual learning rates in lead-acid batteries on emerging technology cost competitiveness, and a cascading diffusion assessment of plug-in hybrid electric vehicle subsidy programs. Notably, the results show that considering learning rates in policy development can save billions of dollars in public funds, while also lending insight into the decision of whether or not to subsidize a given technology.

Assessing first-stage labor progression and its relationship to complications.

PubMed

Hamilton, Emily F; Warrick, Philip A; Collins, Kathleen; Smith, Samuel; Garite, Thomas J

2016-03-01

New labor curves have challenged the traditional understanding of the general pattern of dilation and descent in labor. They also revealed wide variation in the time to advance in dilation. An interval of arrest such as 4 hours did not fall beyond normal limits until dilation had reached 6 cm. Thus, the American College of Obstetricians and Gynecologists/Society for Maternal-Fetal Medicine first-stage arrest criteria, based in part on these findings, are applicable only in late labor. The wide range of time to dilate is unavoidable because cervical dilation has neither a precise nor direct relationship to time. Newer statistical techniques (multifactorial models) can improve precision by incorporating several factors that are related directly to labor progress. At each examination, the calculations adapt to the mother's current labor conditions. They produce a quantitative assessment that is expressed in percentiles. Low percentiles indicate potentially problematic labor progression. The purpose of this study was to assess the relationship between first-stage labor progress- and labor-related complications with the use of 2 different assessment methods. The first method was based on arrest of dilation definitions. The other method used percentile rankings of dilation or station based on adaptive multifactorial models. We included all 4703 cephalic-presenting, term, singleton births with electronic fetal monitoring and cord gases at 2 academic community referral hospitals in 2012 and 2013. We assessed electronic data for route of delivery, all dilation and station examinations, newborn infant status, electronic fetal monitoring tracings, and cord blood gases. The labor-related complication groups included 272 women with cesarean delivery for first-stage arrest, 558 with cesarean delivery for fetal heart rate concerns, 178 with obstetric hemorrhage, and 237 with neonatal depression, which left 3004 women in the spontaneous vaginal birth group. Receiver operating characteristic curves were constructed for each assessment method by measurement of the sensitivity for each complication vs the false-positive rate in the normal reference group. The duration of arrest at ≥6 cm dilation showed poor levels of discrimination for the cesarean delivery interventions (area under the curve, 0.55-0.65; P < .01) and no significant relationship to hemorrhage or neonatal depression. The dilation and station percentiles showed high discrimination for the cesarean delivery-related outcomes (area under the curve, 0.78-0.93; P < .01) and low discrimination for the clinical outcomes of hemorrhage and neonatal depression (area under the curve, 0.58-0.61; P < .01). Duration of arrest of dilation at ≥6 cm showed little or no discrimination for any of the complications. In comparison, percentile rankings that were based on the adaptive multifactorial models showed much higher discrimination for cesarean delivery interventions and better, but low discrimination for hemorrhage. Adaptive multifactorial models present a different method to assess labor progress. Rather than "pass/fail" criteria that are applicable only to dilation in late labor, they produce percentile rankings, assess 2 essential processes for vaginal birth (dilation and descent), and can be applied from 3 cm onward. Given the limitations of labor-progress assessment based solely on the passage of time and because of the extreme variation in decision-making for cesarean delivery for labor disorders, the types of mathematic analyses that are described in this article are logical and promising steps to help standardize labor assessment. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Skeletal effects of megavoltage irradiation in survivors of Wilms' tumor

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

Heaston, D.K.; Libshitz, H.I.; Chan, R.C.

1979-09-01

The skeletal effects of megavoltage irradiation (/sup 60/Co) in 25 long term survivors of Wilms' tumor are described. In general, the changes seen with megavoltage irradiation are as frequent but not as severe as those previously reported after orthovoltage irradiation. Vertebral body changes generally occur within 5 years after irradiation. Scoliosis and/or kyphosis do not usually develop until after five years postirradiation. Kyphotic curves tend to progress after the adolescent growth spurt while scoliotic curves do not. Other bony and nonosseous changes are detailed.

Meta-analysis of single-arm survival studies: a distribution-free approach for estimating summary survival curves with random effects.

PubMed

Combescure, Christophe; Foucher, Yohann; Jackson, Daniel

2014-07-10

In epidemiologic studies and clinical trials with time-dependent outcome (for instance death or disease progression), survival curves are used to describe the risk of the event over time. In meta-analyses of studies reporting a survival curve, the most informative finding is a summary survival curve. In this paper, we propose a method to obtain a distribution-free summary survival curve by expanding the product-limit estimator of survival for aggregated survival data. The extension of DerSimonian and Laird's methodology for multiple outcomes is applied to account for the between-study heterogeneity. Statistics I(2)  and H(2) are used to quantify the impact of the heterogeneity in the published survival curves. A statistical test for between-strata comparison is proposed, with the aim to explore study-level factors potentially associated with survival. The performance of the proposed approach is evaluated in a simulation study. Our approach is also applied to synthesize the survival of untreated patients with hepatocellular carcinoma from aggregate data of 27 studies and synthesize the graft survival of kidney transplant recipients from individual data from six hospitals. Copyright © 2014 John Wiley & Sons, Ltd.

Action of caffeine on x-irradiated HeLa cells. IV. Progression delays and enhanced cell killing at high caffeine concentrations

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

Tolmach, L.J.; Busse, P.M.

1980-05-01

The response of x-irradiated and unirradiated HeLa S3 cells to treatment with caffeine at concentrations between 1 and 10 nM has been examined with respect to both delay in progression through the cell generation cycle and enhancement of the expression of potentially lethal x-ray damage. Progression is delayed in a concentration-dependent fashion: the generation time is doubled at about 4 mM. The duration of G/sub 1/ is lengthened, and the rate of DNA synthesis is reduced, although the kinetics are different in the two phases; the rate of DNA synthesis is usually unaffected at 1 or 2 mM, while theremore » is no concentration threshold for the slowing of progression through G/sub 1/. Progression through G/sub 2/ appears to be unaffected by concentrations up to at least 10 mM. Killing of irradiated cells in G/sub 2/ is somewhat greater after treatment with the higher caffeine concentrations than reported previously for 1 mM. Moreover, an additional mode of killing is observed in irradiated G/sub 1/ cells which had been found previously to be only slightly affected by 1 mM caffeine; they suffer extensive killing at concentrations above 5 mM. The time-survival curves for irradiated, caffeine-treated G/sub 1/ and G/sub 2/ cells have characteristically different shapes. The dose-survival curves for cells treated with the higher caffeine concentrations display steeper terminal slopes and narrower shoulders.« less

[Conservative treatment of idiopathic scoliosis with effective braces: early response to trunk asymmetry may avoid curvature progress].

PubMed

Matussek, J; Dingeldey, E; Wagner, F; Rezai, G; Nahr, K

2014-07-01

Vertical posture of the growing child requires minute central nervous control mechanisms in order to maintain symmetry of the torso in its various activities. Scoliosis describes a constant deviation in the frontal, transverse and sagittal planes from the dynamic symmetry of the trunk. Early intervention with effective bracing, physiotherapy and sports can reverse curve progression during growth spurts, once these are identified in screening. Modern braces have a derotating and reducing effect (mirror effect) on asymmetric body volumes, thus influencing the growing torso and restoring lasting symmetry. Recent data support the use of braces to reverse progressing scoliosis.

Learning curves in health professions education.

PubMed

Pusic, Martin V; Boutis, Kathy; Hatala, Rose; Cook, David A

2015-08-01

Learning curves, which graphically show the relationship between learning effort and achievement, are common in published education research but are not often used in day-to-day educational activities. The purpose of this article is to describe the generation and analysis of learning curves and their applicability to health professions education. The authors argue that the time is right for a closer look at using learning curves-given their desirable properties-to inform both self-directed instruction by individuals and education management by instructors.A typical learning curve is made up of a measure of learning (y-axis), a measure of effort (x-axis), and a mathematical linking function. At the individual level, learning curves make manifest a single person's progress towards competence including his/her rate of learning, the inflection point where learning becomes more effortful, and the remaining distance to mastery attainment. At the group level, overlaid learning curves show the full variation of a group of learners' paths through a given learning domain. Specifically, they make overt the difference between time-based and competency-based approaches to instruction. Additionally, instructors can use learning curve information to more accurately target educational resources to those who most require them.The learning curve approach requires a fine-grained collection of data that will not be possible in all educational settings; however, the increased use of an assessment paradigm that explicitly includes effort and its link to individual achievement could result in increased learner engagement and more effective instructional design.

Spherical nanoindentation stress–strain curves

DOE PAGES

Pathak, Siddhartha; Kalidindi, Surya R.

2015-03-24

Although indentation experiments have long been used to measure the hardness and Young's modulus, the utility of this technique in analyzing the complete elastic–plastic response of materials under contact loading has only been realized in the past few years – mostly due to recent advances in testing equipment and analysis protocols. This paper provides a timely review of the recent progress made in this respect in extracting meaningful indentation stress–strain curves from the raw datasets measured in instrumented spherical nanoindentation experiments. These indentation stress–strain curves have produced highly reliable estimates of the indentation modulus and the indentation yield strength inmore » the sample, as well as certain aspects of their post-yield behavior, and have been critically validated through numerical simulations using finite element models as well as direct in situ scanning electron microscopy (SEM) measurements on micro-pillars. Much of this recent progress was made possible through the introduction of a new measure of indentation strain and the development of new protocols to locate the effective zero-point of initial contact between the indenter and the sample in the measured datasets. As a result, this has led to an important key advance in this field where it is now possible to reliably identify and analyze the initial loading segment in the indentation experiments.« less

A comparison of four different lens mappers.

PubMed

Larrue, Denis; Legeard, Morgane

2014-11-01

Recently, a number of lens mappers have become available for measuring the detailed optical properties of progressive addition lenses (PALs). The goal of this study was to compare the results obtained from several different lens mappers for a range of different lenses. The optical power maps of six lenses-two single-vision lenses, a parallel-sided slide, a flat prism, and two progressive lenses-were measured using four different lens mappers: the Dual Lens Mapper, the Nimo TR4005, the Rotlex Class Plus, and the Visionix VM2500. The repeatability of the instruments was also evaluated. All lens mappers gave very repeatable measurements; however, measurements among the lens mappers varied considerably. Differences appeared to be above the tolerance at the optical center for measurements of single-vision lenses, and these differences increase in the periphery up to 1.00 diopter. Similar differences were observed for the PALs, even increased by prism and base curve effect, with figures greater than 1 diopter in the periphery. The measurements made on the prism and lenses with different base curves suggest that base curve, thickness, and prismatic effect can all contribute to the differences among instruments. Measurements of a given lens taken with different lens mappers can vary substantially. Particular caution should be exercised when interpreting power maps for PALs taken with different instruments.

Therapy response assessment after radioembolization of patients with hepatocellular carcinoma--comparison of MR imaging with gadolinium ethoxybenzyl diethylenetriamine penta-acetic acid and gadobutrol.

PubMed

Schelhorn, Juliane; Best, Jan; Reinboldt, Marcus P; Gerken, Guido; Ruhlmann, Marcus; Lauenstein, Thomas C; Antoch, Gerald; Kinner, Sonja

2015-07-01

To compare the utility of gadolinium ethoxybenzyl diethylenetriamine penta-acetic acid (Gd-EOB-DTPA), a liver-specific magnetic resonance (MR) imaging contrast agent, versus gadobutrol for treatment response evaluation of hepatocellular carcinoma (HCC) after radioembolization. This prospective study included 50 patients with HCC undergoing radioembolization. All patients underwent contrast-enhanced computed tomography (CT) and MR imaging with gadobutrol and Gd-EOB-DTPA on 2 consecutive days before radioembolization and 30 days, 90 days, 180 days, and 270 days after radioembolization. The standard of reference indicating tumor progression was CT combined with either α-fetoprotein or γ-glutamyltransferase. Gadobutrol-enhanced MR imaging, Gd-EOB-DTPA-enhanced MR imaging without late phase imaging (Gd-EOB-DTPA-), and Gd-EOB-DTPA-enhanced MR imaging with late phase imaging (Gd-EOB-DTPA+) were evaluated by 2 radiologists in consensus using a 4-point scale: 1 = definitely no tumor progression; 2 = probably no tumor progression; 3 = probably tumor progression; 4 = definitely tumor progression. Diagnostic accuracy was assessed with receiver operating characteristic analysis. Tumor progression was detected in 14 of 82 study visits according to the reference standard. Pairwise comparison of the area under the curve showed a tendency toward a larger area under the curve for Gd-EOB-DTPA+ compared with gadobutrol (P = .056). Sensitivity and specificity were higher in Gd-EOB-DTPA+ (0.929 and 0.971) than in Gd-EOB-DTPA- (0.786 and 0.941) or gadobutrol (0.643 and 0.956). In 2 cases, tumor progression was detected by Gd-EOB-DTPA+ and by an increase in α-fetoprotein, but not by CT, gadobutrol, or Gd-EOB-DTPA-. Gd-EOB-DTPA+ MR imaging was not inferior to gadobutrol-enhanced MR imaging in therapy response evaluation after radioembolization and may allow a more accurate detection of early HCC recurrence in single cases. Copyright © 2015 SIR. Published by Elsevier Inc. All rights reserved.

Infrared light curves of type Ia supernovae

DOE PAGES

Phillips, M. M.; Krisciunas, K.; Suntzeff, N. B.; ...

2003-10-02

This article provides a progress report on a collaborative program at the Las Campanas and Cerro Tololo Observatories to observe the near-IR light curves of Type Ia supernovae. We discuss how the morphologies of the JHK light curves change as a function of the decline rate parameter Δm 15 (B). Evidence is presented which indicates that the absolute magnitudes in the H band have little or no dependence on the decline rate, suggesting that SNe Ia may be nearly perfect cosmological standard candles in the near-IR. A preliminary Hubble diagram in the H band is presented and compared with amore » similar diagram in V for the same objects. Finally, observations of two peculiar supernovae, 1999ac and 2001ay, are briefly discussed.« less

Nondestructive detection and measurement of hydrogen embrittlement

DOEpatents

Alex, Franklin; Byrne, Joseph Gerald

1977-01-01

A nondestructive system and method for the determination of the presence and extent of hydrogen embrittlement in metals, alloys, and other crystalline structures subject thereto. Positron annihilation characteristics of the positron-electron annihilation within the tested material provide unique energy distribution curves for each type of material tested at each respective stage of hydrogen embrittlement. Gamma radiation resulting from such annihilation events is detected and statistically summarized by appropriate instrumentation to reveal the variations of electron activity within the tested material caused by hydrogen embrittlement therein. Such data from controlled tests provides a direct indication of the relative stages of hydrogen embrittlement in the form of unique energy distribution curves which may be utilized as calibration curves for future comparison with field tests to give on-site indication of progressive stages of hydrogen embrittlement.

Perspectives on Geometrodynamics: The Nonlinear Dynamics of Curved Spacetime

NASA Astrophysics Data System (ADS)

Thorne, Kip S.

2012-03-01

In the 1950s John Archibald Wheeler exhorted his students and colleagues to explore ``Geometrodynamics,'' i.e. the dynamical behavior of curved spacetime, as predicted by Einstein's general relativity theory. Unfortunately, the research tools of that era were inadequate for the task. This has changed over the past ten years and will change further in the coming decade, thanks to two new sets of tools - numerical relativity, and gravitational wave observations, coupled to theory. In this lecture, I will review the progress and prospects for geometrodynamics, focusing especially on: 1. Geometrodynamics near singularities, 2. Geometrodynamics triggered by colliding black holes, 3. Geometrodynamics triggered by black-string instabilities in four space dimensions, and 4. Preparations for observing the dynamics of curved spacetime with interferometric gravitational wave detectors: LIGO and its international partners.

CONTRAIS: CONservative TReatment for Adolescent Idiopathic Scoliosis: a randomised controlled trial protocol

PubMed Central

2013-01-01

Background Idiopathic scoliosis is a three-dimensional structural deformity of the spine that occurs in children and adolescents. Recent reviews on bracing and exercise treatment have provided some evidence for effect of these interventions. The purpose of this study is to improve the evidence base regarding the effectiveness of conservative treatments for preventing curve progression in idiopathic scoliosis. Methods/design Patients: Previously untreated girls and boys with idiopathic scoliosis, 9 to 17 years of age with at least one year of remaining growth and a curve Cobb angle of 25–40 degrees will be included. A total of 135 participants will be randomly allocated in groups of 45 patients each to receive one of the three interventions. Interventions: All three groups will receive a physical activity prescription according to the World Health Organisation recommendations. One group will additionally wear a hyper-corrective night-time brace. One group will additionally perform postural scoliosis-specific exercises. Outcome: Participation in the study will last until the curve has progressed, or until cessation of skeletal growth. Outcome variables will be measured every 6 months. The primary outcome variable, failure of treatment, is defined as progression of the Cobb angle more than 6 degrees, compared to the primary x-ray, seen on two consecutive spinal standing x-rays taken with 6 months interval. Secondary outcome measures include the SRS-22r and EQ5D-Y quality of life questionnaires, the International Physical Activity Questionnaire (IPAQ) short form, and Cobb angle at end of the study. Discussion This trial will evaluate which of the tested conservative treatment approaches that is the most effective for patients with adolescent idiopathic scoliosis. Trial registration NCT01761305 PMID:24007599

CONTRAIS: CONservative TReatment for Adolescent Idiopathic Scoliosis: a randomised controlled trial protocol.

PubMed

Abbott, Allan; Möller, Hans; Gerdhem, Paul

2013-09-05

Idiopathic scoliosis is a three-dimensional structural deformity of the spine that occurs in children and adolescents. Recent reviews on bracing and exercise treatment have provided some evidence for effect of these interventions. The purpose of this study is to improve the evidence base regarding the effectiveness of conservative treatments for preventing curve progression in idiopathic scoliosis. Previously untreated girls and boys with idiopathic scoliosis, 9 to 17 years of age with at least one year of remaining growth and a curve Cobb angle of 25-40 degrees will be included. A total of 135 participants will be randomly allocated in groups of 45 patients each to receive one of the three interventions. All three groups will receive a physical activity prescription according to the World Health Organisation recommendations. One group will additionally wear a hyper-corrective night-time brace. One group will additionally perform postural scoliosis-specific exercises. Participation in the study will last until the curve has progressed, or until cessation of skeletal growth. OUTCOME variables will be measured every 6 months. The primary outcome variable, failure of treatment, is defined as progression of the Cobb angle more than 6 degrees, compared to the primary x-ray, seen on two consecutive spinal standing x-rays taken with 6 months interval. Secondary outcome measures include the SRS-22r and EQ5D-Y quality of life questionnaires, the International Physical Activity Questionnaire (IPAQ) short form, and Cobb angle at end of the study. This trial will evaluate which of the tested conservative treatment approaches that is the most effective for patients with adolescent idiopathic scoliosis. NCT01761305.

Precision Learning Assessment: An Alternative to Traditional Assessment Techniques.

ERIC Educational Resources Information Center

Caltagirone, Paul J.; Glover, Christopher E.

1985-01-01

A continuous and curriculum-based assessment method, Precision Learning Assessment (PLA), which integrates precision teaching and norm-referenced techniques, was applied to a math computation curriculum for 214 third graders. The resulting districtwide learning curves defining average annual progress through the computation curriculum provided…

40 CFR 52.2239 - Original Identification of plan section.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Carbon Monoxide Reasonable Further Progress (RFP) curve adopted on May 8, 1985. (ii) Other material. (A...) Permit for battery receiving and breaking operation for Refined Metals Corporation which became effective... Efficiency. (35) Rule 1200-3-18-.46 Test Method for Determination of Solvent...

40 CFR 52.2239 - Original Identification of plan section.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Carbon Monoxide Reasonable Further Progress (RFP) curve adopted on May 8, 1985. (ii) Other material. (A...) Permit for battery receiving and breaking operation for Refined Metals Corporation which became effective... Efficiency. (35) Rule 1200-3-18-.46 Test Method for Determination of Solvent...

Characteristics of Kodak Insight, an F-speed intraoral film.

PubMed

Ludlow, J B; Platin, E; Mol, A

2001-01-01

This study reports film speed, contrast, exposure latitude, resolution, and response to processing solution depletion of Kodak Insight intraoral film. Densitometric curves were generated by using International Standards Organization protocol. Additional curves were generated for Ultra-speed, Ektaspeed Plus, and Insight films developed in progressively depleted processing solutions. Eight observers viewed images of a resolution test tool for maximum resolution assessment. Images of an aluminum step-wedge were reviewed to determine useful exposure latitude. Insight's sensitivity in fresh automatic processor solutions places it in the F-speed group. An average gradient of 1.8 was found with all film types. Insight provided 93% of the useful exposure latitude of Ektaspeed Plus film. Insight maintained contrast in progressively depleted processing solutions. Like Ektaspeed Plus, Insight was able to resolve at least 20 line-pairs per millimeter. Under International Standards Organization conditions, Insight required only 77% of the exposure of Ektaspeed Plus film. Insight film provided stable contrast in depleted processing solutions.

Modeling of stress/strain behavior of fiber-reinforced ceramic matrix composites including stress redistribution

NASA Technical Reports Server (NTRS)

Mital, Subodh K.; Murthy, Pappu L. N.; Chamis, Christos C.

1994-01-01

A computational simulation procedure is presented for nonlinear analyses which incorporates microstress redistribution due to progressive fracture in ceramic matrix composites. This procedure facilitates an accurate simulation of the stress-strain behavior of ceramic matrix composites up to failure. The nonlinearity in the material behavior is accounted for at the constituent (fiber/matrix/interphase) level. This computational procedure is a part of recent upgrades to CEMCAN (Ceramic Matrix Composite Analyzer) computer code. The fiber substructuring technique in CEMCAN is used to monitor the damage initiation and progression as the load increases. The room-temperature tensile stress-strain curves for SiC fiber reinforced reaction-bonded silicon nitride (RBSN) matrix unidirectional and angle-ply laminates are simulated and compared with experimentally observed stress-strain behavior. Comparison between the predicted stress/strain behavior and experimental stress/strain curves is good. Collectively the results demonstrate that CEMCAN computer code provides the user with an effective computational tool to simulate the behavior of ceramic matrix composites.

Utilization of integrated Michaelis-Menten equations for enzyme inhibition diagnosis and determination of kinetic constants using Solver supplement of Microsoft Office Excel.

PubMed

Bezerra, Rui M F; Fraga, Irene; Dias, Albino A

2013-01-01

Enzyme kinetic parameters are usually determined from initial rates nevertheless, laboratory instruments only measure substrate or product concentration versus reaction time (progress curves). To overcome this problem we present a methodology which uses integrated models based on Michaelis-Menten equation. The most severe practical limitation of progress curve analysis occurs when the enzyme shows a loss of activity under the chosen assay conditions. To avoid this problem it is possible to work with the same experimental points utilized for initial rates determination. This methodology is illustrated by the use of integrated kinetic equations with the well-known reaction catalyzed by alkaline phosphatase enzyme. In this work nonlinear regression was performed with the Solver supplement (Microsoft Office Excel). It is easy to work with and track graphically the convergence of SSE (sum of square errors). The diagnosis of enzyme inhibition was performed according to Akaike information criterion. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Current concepts and controversies on adolescent idiopathic scoliosis: Part I.

PubMed

Sud, Alok; Tsirikos, Athanasios I

2013-03-01

Adolescent idiopathic scoliosis is the most common spinal deformity encountered by General Orthopaedic Surgeons. Etiology remains unclear and current research focuses on genetic factors that may influence scoliosis development and risk of progression. Delayed diagnosis can result in severe deformities which affect the coronal and sagittal planes, as well as the rib cage, waistline symmetry, and shoulder balance. Patient's dissatisfaction in terms of physical appearance and mechanical back pain, as well as the risk for curve deterioration are usually the reasons for treatment. Conservative management involves mainly bracing with the aim to stop or slow down scoliosis progression during growth and if possible prevent the need for surgical treatment. This is mainly indicated in young compliant patients with a large amount of remaining growth and progressive curvatures. Scoliosis correction is indicated for severe or progressive curves which produce significant cosmetic deformity, muscular pain, and patient discontent. Posterior spinal arthrodesis with Harrington instrumentation and bone grafting was the first attempt to correct the coronal deformity and replace in situ fusion. This was associated with high pseudarthrosis rates, need for postoperative immobilization, and flattening of sagittal spinal contour. Segmental correction techniques were introduced along with the Luque rods, Harri-Luque, and Wisconsin systems. Correction in both coronal and sagittal planes was not satisfactory and high rates of nonunion persisted until Cotrel and Dubousset introduced the concept of global spinal derotation. Development of pedicle screws provided a powerful tool to correct three-dimensional vertebral deformity and opened a new era in the treatment of scoliosis.

Testing and analysis of flat and curved panels with multiple cracks

NASA Technical Reports Server (NTRS)

Broek, David; Jeong, David Y.; Thomson, Douglas

1994-01-01

An experimental and analytical investigation of multiple cracking in various types of test specimens is described in this paper. The testing phase is comprised of a flat unstiffened panel series and curved stiffened and unstiffened panel series. The test specimens contained various configurations for initial damage. Static loading was applied to these specimens until ultimate failure, while loads and crack propagation were recorded. This data provides the basis for developing and validating methodologies for predicting linkup of multiple cracks, progression to failure, and overall residual strength. The results from twelve flat coupon and ten full scale curved panel tests are presented. In addition, an engineering analysis procedure was developed to predict multiple crack linkup. Reasonable agreement was found between predictions and actual test results for linkup and residual strength for both flat and curved panels. The results indicate that an engineering analysis approach has the potential to quantitatively assess the effect of multiple cracks in the arrest capability of an aircraft fuselage structure.

The Lumbar Lordosis in Males and Females, Revisited.

PubMed

Hay, Ori; Dar, Gali; Abbas, Janan; Stein, Dan; May, Hila; Masharawi, Youssef; Peled, Nathan; Hershkovitz, Israel

2015-01-01

Whether differences exist in male and female lumbar lordosis has been debated by researchers who are divided as to the nature of variations in the spinal curve, their origin, reasoning, and implications from a morphological, functional and evolutionary perspective. Evaluation of the spinal curvature is constructive in understanding the evolution of the spine, as well as its pathology, planning of surgical procedures, monitoring its progression and treatment of spinal deformities. The aim of the current study was to revisit the nature of lumbar curve in males and females. Our new automated method uses CT imaging of the spine to measure lumbar curvature in males and females. The curves extracted from 158 individuals were based on the spinal canal, thus avoiding traditional pitfalls of using bone features for curve estimation. The model analysis was carried out on the entire curve, whereby both local and global descriptors were examined in a single framework. Six parameters were calculated: segment length, curve length, curvedness, lordosis peak location, lordosis cranial peak height, and lordosis caudal peak height. Compared to males, the female spine manifested a statistically significant greater curvature, a caudally located lordotic peak, and greater cranial peak height. As caudal peak height is similar for males and females, the illusion of deeper lordosis among females is due partially to the fact that the upper part of the female lumbar curve is positioned more dorsally (more backwardly inclined). Males and females manifest different lumbar curve shape, yet similar amount of inward curving (lordosis). The morphological characteristics of the female spine were probably developed to reduce stress on the vertebral elements during pregnancy and nursing.

Patterns and predictors of skin score change in early diffuse systemic sclerosis from the European Scleroderma Observational Study

PubMed Central

Herrick, Ariane L; Peytrignet, Sebastien; Lunt, Mark; Pan, Xiaoyan; Hesselstrand, Roger; Mouthon, Luc; Silman, Alan J; Dinsdale, Graham; Brown, Edith; Czirják, László; Distler, Jörg H W; Distler, Oliver; Fligelstone, Kim; Gregory, William J; Ochiel, Rachel; Vonk, Madelon C; Ancuţa, Codrina; Ong, Voon H; Farge, Dominique; Hudson, Marie; Matucci-Cerinic, Marco; Balbir-Gurman, Alexandra; Midtvedt, Øyvind; Jobanputra, Paresh; Jordan, Alison C; Stevens, Wendy; Moinzadeh, Pia; Hall, Frances C; Agard, Christian; Anderson, Marina E; Diot, Elisabeth; Madhok, Rajan; Akil, Mohammed; Buch, Maya H; Chung, Lorinda; Damjanov, Nemanja S; Gunawardena, Harsha; Lanyon, Peter; Ahmad, Yasmeen; Chakravarty, Kuntal; Jacobsen, Søren; MacGregor, Alexander J; McHugh, Neil; Müller-Ladner, Ulf; Riemekasten, Gabriela; Becker, Michael; Roddy, Janet; Carreira, Patricia E; Fauchais, Anne Laure; Hachulla, Eric; Hamilton, Jennifer; İnanç, Murat; McLaren, John S; van Laar, Jacob M; Pathare, Sanjay; Proudman, Susanna M; Rudin, Anna; Sahhar, Joanne; Coppere, Brigitte; Serratrice, Christine; Sheeran, Tom; Veale, Douglas J; Grange, Claire; Trad, Georges-Selim; Denton, Christopher P

2018-01-01

Objectives Our aim was to use the opportunity provided by the European Scleroderma Observational Study to (1) identify and describe those patients with early diffuse cutaneous systemic sclerosis (dcSSc) with progressive skin thickness, and (2) derive prediction models for progression over 12 months, to inform future randomised controlled trials (RCTs). Methods The modified Rodnan skin score (mRSS) was recorded every 3 months in 326 patients. ‘Progressors’ were defined as those experiencing a 5-unit and 25% increase in mRSS score over 12 months (±3 months). Logistic models were fitted to predict progression and, using receiver operating characteristic (ROC) curves, were compared on the basis of the area under curve (AUC), accuracy and positive predictive value (PPV). Results 66 patients (22.5%) progressed, 227 (77.5%) did not (33 could not have their status assessed due to insufficient data). Progressors had shorter disease duration (median 8.1 vs 12.6 months, P=0.001) and lower mRSS (median 19 vs 21 units, P=0.030) than non-progressors. Skin score was highest, and peaked earliest, in the anti-RNA polymerase III (Pol3+) subgroup (n=50). A first predictive model (including mRSS, duration of skin thickening and their interaction) had an accuracy of 60.9%, AUC of 0.666 and PPV of 33.8%. By adding a variable for Pol3 positivity, the model reached an accuracy of 71%, AUC of 0.711 and PPV of 41%. Conclusions Two prediction models for progressive skin thickening were derived, for use both in clinical practice and for cohort enrichment in RCTs. These models will inform recruitment into the many clinical trials of dcSSc projected for the coming years. Trial registration number NCT02339441. PMID:29306872

Comparison of O-(2-18F-Fluoroethyl)-L-Tyrosine Positron Emission Tomography and Perfusion-Weighted Magnetic Resonance Imaging in the Diagnosis of Patients with Progressive and Recurrent Glioma: A Hybrid Positron Emission Tomography/Magnetic Resonance Study.

PubMed

Verger, Antoine; Filss, Christian P; Lohmann, Philipp; Stoffels, Gabriele; Sabel, Michael; Wittsack, Hans-J; Kops, Elena Rota; Galldiks, Norbert; Fink, Gereon R; Shah, Nadim J; Langen, Karl-Josef

2018-05-01

To compare the diagnostic performance of O-(2- 18 F-fluoroethyl)-L-tyrosine ( 18 F-FET) positron emission tomography (PET) and perfusion-weighted magnetic resonance imaging (PWI) for the diagnosis of progressive or recurrent glioma. Thirty-two pretreated gliomas (25 progressive or recurrent tumors, 7 treatment-related changes) were investigated with 18 F-FET PET and PWI via a hybrid PET/magnetic resonance scanner. Volumes of interest with a diameter of 16 mm were centered on the maximum of abnormality in the tumor area in PET and PWI maps (relative cerebral blood volume, relative cerebral blood flow, mean transit time) and the contralateral unaffected hemisphere. Mean and maximum tumor-to-brain ratios as well as dynamic data for 18 F-FET uptake were calculated. Diagnostic accuracies were evaluated by receiver operating characteristic analyses, calculating the area under the curve. 18 F-FET PET showed a significant greater sensitivity to detect abnormalities in pretreated gliomas than PWI (76% vs. 52%, P = 0.03). The maximum tumor-to-brain ratio of 18 F-FET PET was the only parameter that discriminated treatment-related changes from progressive or recurrent gliomas (area under the curve, 0.78; P = 0.03, best cut-off 2.61; sensitivity 80%, specificity 86%, accuracy 81%). Among patients with signal abnormality in both modalities, 75% revealed spatially incongruent local hot spots. This pilot study suggests that 18 F-FET PET is superior to PWI to diagnose progressive or recurrent glioma. Copyright © 2018 Elsevier Inc. All rights reserved.

The relationship between liver stiffness measurement and outcome in patients with chronic hepatitis C and cirrhosis: a retrospective longitudinal hospital study.

PubMed

Sultanik, P; Kramer, L; Soudan, D; Bouam, S; Meritet, J-F; Vallet-Pichard, A; Fontaine, H; Bousquet, L; Boueyre, E; Corouge, M; Sogni, P; Pol, S; Mallet, V

2016-09-01

There is a relationship between liver stiffness measurement (LSM) and outcome of HCV patients. To evaluate the performance of LSM to predict outcome of HCV patients at risk of liver-related complication. We established a retrospective longitudinal cohort of 341 HCV patients with unequivocal cirrhosis. All underwent LSM and were followed from September 2006 to July 2015. Outcome measure was a composite end-point of end-stage liver disease (ESLD) and/or hepatocellular carcinoma (HCC). Cox models and areas under receiver operating characteristic (AUROC) curves were used to evaluate independent risk factors of outcome. Overall, LSM was below the 12.5 kPa threshold in 129 (37.8%) patients, including three-fourth and one-third of patients with or without a sustained virological response respectively. Liver disease progressed in 136 (39.9%) patients after a median observational period of 23.5 months. Older age, male gender, alcohol use disorders, metabolic syndrome and LSM were independent risk factors of liver disease progression. Age, alcohol use disorders and LSM were independently associated with ESLD. Age, gender and metabolic syndrome, but not LSM, were associated with HCC. The AUROC curves for disease progression, ESLD and HCC were 0.67, 0.70 and 0.58 respectively. Patients with a liver stiffness >12.5 kPa were at the highest risk of liver disease progression; below 12.5 kPa, liver stiffness was not discriminant. Liver stiffness measurement is not a surrogate of disease progression of HCV patients with cirrhosis. HCV patients with cirrhosis should undergo the recommended follow-up, regardless of liver stiffness measurement. © 2016 John Wiley & Sons Ltd.

Spectroscopic constants and potential energy curve of the iodine weakly bound 1u state correlating with the I(2P1/2) + I(2P1/2) dissociation limit

NASA Astrophysics Data System (ADS)

Akopyan, M. E.; Baturo, V. V.; Lukashov, S. S.; Poretsky, S. A.; Pravilov, A. M.

2015-01-01

The stepwise three-step three-color laser population of the I2(β1g, νβ, Jβ) rovibronic states via the B0u+, νB, JB rovibronic states and rovibronic levels of the 1u(bb) and 0g+(bb) states mixed by hyperfine interaction is used for determination of rovibronic level energies of the weakly bound I2(1u(bb)) state. Dunham coefficients of the state, Yi0 (i = 0-3), Yi1 (i = 0-2), Y02 and Y12 for the {{v}{{1u}}} = 1-5, 8, 10, 15 and {{J}{{1u}}} ≈ 9-87 ranges, the dissociation energy of the state, De, and equilibrium I-I distance, Re, as well as the potential energy curve are determined. There are aperiodicities in the excitation spectrum corresponding to the β, νβ = 23, Jβ ← 1u(bb), ν1u = 4, 5, J1u progressions in the I2 + Rg = He, Ar mixture, namely, a great number of lines which do not coincide with the R or P line progressions. Their positions conflict with the ΔJ-even selection rule. Furthermore, they do not correspond to the ΔJ-odd progression.

Taking Another Look: Sensuous, Consistent Form.

ERIC Educational Resources Information Center

Townley, Mary Ross

1983-01-01

There is a natural progression from making single objects to creating sculpture. By modeling the forms of objects like funnels and light bulbs, students become aware of the quality of curves and the edges of angles. Sculptural form in architecture can be understood as consistency in the forms. (CS)

ESTIMATION OF ACUTE TOXICITY BY FITTING A DOSE-TIME RESPONSE SURFACE

EPA Science Inventory

In acute toxicity testing, organisms are continuously exposed to progressively increasing concentrations of a chemical and deaths of test organisms are recorded at several selected times. he results of the test are traditionally summarized by a dose-response curve, and the time c...

Design for progressive fracture in composite shell structures

NASA Technical Reports Server (NTRS)

Minnetyan, Levon; Murthy, Pappu L. N.

1992-01-01

The load carrying capability and structural behavior of composite shell structures and stiffened curved panels are investigated to provide accurate early design loads. An integrated computer code is utilized for the computational simulation of composite structural degradation under practical loading for realistic design. Damage initiation, growth, accumulation, and propagation to structural fracture are included in the simulation. Progressive fracture investigations providing design insight for several classes of composite shells are presented. Results demonstrate the significance of local defects, interfacial regions, and stress concentrations on the structural durability of composite shells.

Thermoluminescence characteristics of a chondrite (Holbrook) and an aubrite achondrite (Norton County) meteorites.

PubMed

Bossin, Lily; Kazakis, Nikolaos A; Kitis, George; Tsirliganis, Nestor C

2017-09-01

The present study constitutes the first part of a meteorite project, currently in progress, towards the full and thorough dosimetric study (TL and OSL) of two different meteorites of recent fall, Norton County and Holbrook. Both meteorites exhibit strong TL sensitivity, linear dose response and no saturation for doses up to 2kGy. However, the two meteorites exhibited a very dissimilar TL glow curve and behaviour regarding sensitization and fading. Notably, the Norton County aubrite achondrite was found to exhibit a strong fading of the high-temperature peak (~300°C), attributed to anomalous fading, whereas Holbrook did not seem to show signs of anomalous fading. Since quantitative conclusions regarding the thermal and irradiation history of meteorites, require knowledge of the detailed peak structure of the glow curve and deeper understanding of the trapping mechanism, the glow curves, after irradiation in the range 10-2000Gy, were deconvoluted using general order kinetics. The fitting parameters extracted point towards complex non-strictly first order mechanisms with a multitude of traps acting very differently. All the above, combined with future OSL measurements, currently in progress, are expected to shed light on the nature of the involved traps in both phenomena (energy depth, light-resistance etc), which would allow to extract more concrete conclusions about their history. Copyright © 2017 Elsevier Ltd. All rights reserved.

The double nucleation model for sickle cell haemoglobin polymerization: full integration and comparison with experimental data.

PubMed

Medkour, Terkia; Ferrone, Frank; Galactéros, Frédéric; Hannaert, Patrick

2008-06-01

Sickle cell haemoglobin (HbS) polymerization reduces erythrocyte deformability, causing deleterous vaso-occlusions. The double-nucleation model states that polymers grow from HbS aggregates, the nuclei, (i) in solution (homogeneous nucleation), (ii) onto existing polymers (heterogeneous nucleation). When linearized at initial HbS concentration, this model predicts early polymerization and its characteristic delay-time (Ferrone et al. J Mol Biol 183(4):591-610, 611-631, 1985). Addressing its relevance for describing complete polymerization, we constructed the full, non-linearized model (Simulink), The MathWorks). Here, we compare the simulated outputs to experimental progress curves (n = 6-8 different [HbS], 3-6 mM range, from Ferrone's group). Within 10% from start, average root mean square (rms) deviation between simulated and experimental curves is 0.04 +/- 0.01 (25 degrees C, n = 8; mean +/- standard error). Conversely, for complete progress curves, averaged rms is 0.48 +/- 0.04. This figure is improved to 0.13 +/- 0.01 by adjusting heterogeneous pathway parameters (p < 0.01): the nucleus stability (sigma(2) micro( cc ): + 40%), and the fraction of polymer surface available for nucleation (phi), from 5e(-7), (3 mM) to 13 (6 mM). Similar results are obtained at 37 degrees C. We conclude that the physico-chemical description of heterogeneous nucleation warrants refinements in order to capture the whole HbS polymerization process.

Nature of the Renal Concentrating Defect in Sickle Cell Disease*

PubMed Central

Hatch, Fred E.; Culbertson, James W.; Diggs, Lemuel W.

1967-01-01

Free water reabsorption (TcH2O) measured during 10% mannitol diuresis and subsequently during 3% saline diuresis was compared in patients with sickle cell anemia and in normal subjects. During mannitol infusion, TcH2O progressively rose with increasing osmolar clearance (Cosm) and reached a maximal level in both groups studied. During hypertonic saline diuresis, TcH2O progressively rose in the normal subjects and exceeded the maximal levels attained during mannitol diuresis, with no evidence of a maximal TcH2O level appearing. In contrast, none of the saline curves significantly exceeded the mannitol curves in the sickle cell patients but tended to parallel the mannitol curves at comparable rates of solute clearance. Since TcH2O is an index of both solute (sodium) transport from the loop of Henle and solute accumulation in the hypertonic medullary interstitium, tubular sodium handling was examined in both sickle cell patients and control subjects alike. No difference in the tubular transport of sodium could be demonstrated either under conditions of sodium loading or under conditions in which the tubular sodium load was low (water diuresis). These data support the conclusion that the defect in urinary concentration in sickle cell patients is caused by a limitation in maintaining a high concentration of solute in the medullary interstitium, thus limiting the rate of TcH2O from the collecting duct. PMID:6023770

Efficacy of plasma vascular endothelial growth factor in monitoring first-line chemotherapy in patients with advanced non-small cell lung cancer

PubMed Central

2009-01-01

Background Along with the development of new cancer therapeutics, more effective tools for the estimation of response to therapy and prediction of disease progression are required for the better management of inoperable cancer patients. Methods We studied 134 newly diagnosed and primarily untreated advanced non-small cell lung cancer patients and 100 controls. Forty two patients received platinum-based chemotherapy. Plasma VEGF levels were quantified in all samples at baseline and also before second and third chemotherapy cycle in 42 patients and correlated with response to therapy as assessed by computed tomography after the third chemotherapy cycle. Results We observed that, patients who went into remission had significantly lower baseline VEGF levels before second and third cycles of chemotherapy when compared with patients with no change and progression. Plasma VEGF levels showed a greater decrease from cycle 1 to 2 and from cycle 1 to 3 in patients who showed remission in comparison to those with no change or progression. Plasma VEGF levels before the second cycle detected poor response to therapy with a sensitivity and specificity of 76.9% and 75.0%, respectively (area under the ROC curve = 0.724). Early prediction of disease progression was achieved with a sensitivity and specificity of 71.4% for plasma VEGF before cycle 2 (area under the ROC curve = 0.805). The kinetics of VEGF form cycle 1 to 2 and cycle 1 to 3 also gave significant information for predicting disease progression as well as insufficient therapy response. Conclusion Monitoring of plasma VEGF levels during the course of first-line chemotherapy could identify patients who are likely to have insufficient response to therapy and disease progression at an early stage. This may help in individualizing treatment and could lead to better management of the advanced stage lung cancer. PMID:19958548

Contemporary Labor Patterns and Maternal Age

PubMed Central

ZAKI, Mary N.; HIBBARD, Judith U.; KOMINIAREK, Michelle A.

2013-01-01

Objective To evaluate labor progress and length according to maternal age. Methods Data were abstracted from the Consortium on Safe Labor, a multicenter retrospective study from 19 hospitals in the United States. We studied 120,442 laboring gravid women with singleton, term, cephalic fetuses with normal outcomes and without a prior cesarean delivery from 2002 to 2008. Maternal age categories were less than 20 years old, greater than or equal to 20 to less than 30, greater than or equal to 30 to less than 40 and greater than or 40 years old, with the reference being less than 20 years. Interval-censored regression analysis was used to determine median traverse times (progression cm by cm) with 95th percentiles, adjusting for covariates (race, admission body mass index, diabetes, gestational age, induction, augmentation, epidural use and birth weight). A repeated-measures analysis with an eighth-degree polynomial model was used to construct mean labor curves for each maternal age category, stratified by parity. Results Traverse times for nulliparous women demonstrated the time to progress from 4 to 10 cm decreased as age increased up to age 40 (median 8.5 hrs vs. 7.8 hrs in those greater than or equal to 20 to less than 30 year old group and 7.4 hrs in the greater than or equal to 30 to less than 40 year old group, p<0.001); the length of the second stage with and without epidural increased with age (p<0.001). For multiparous women, time to progress from 4 to 10 cm decreased as age increased (median 8.8 hrs, 7.5, 6.7 and 6.5 from the youngest to oldest maternal age groups, p<0.001). Labor progressed faster with increasing maternal age in both nulliparous and multiparous women in the labor curves analysis. Conclusion The first stage of labor progressed more quickly with increasing age for nulliparous up to age 40 and all multiparous women. Contemporary labor management should account for maternal age. PMID:24104787

Induction of micronuclei in human fibroblasts across the Bragg curve of energetic heavy ions

NASA Technical Reports Server (NTRS)

Hada, Megumi; Rusek, Adam; Cucinotta, Francis A.; Wu, Honglu

2006-01-01

The space environment consists of a varying field of radiation particles including high energy ions, with spacecraft shielding material providing the major protection to astronauts from harmful exposure. Unlike low-L or X-rays, the presence of shielding does not always reduce the radiation risks for energetic charged particle exposure. Although the dose delivered by the charged particle increases sharply as the particle approaches the Bragg peak, the Bragg curve does not necessarily represent the biological damage along the particle traversal. The "biological Bragg curve" is dependent on the energy and the type of the primary particle, and may vary for different biological endpoints. To investigate "biological Bragg curves", we analyzed micronuclei (MN) induction along the particle traversal of Si and Fe ions at incident energies of 300 MeV/nucleon and 1 GeV/nucleon. A quantitative biological response curve did not reveal an increased yield of MN at the location of the Bragg peak. However, the ratio of mono-to bi-nucleated cells, which indicates inhibition in cell progression, increased at the Bragg peak location. These results confirm the hypothesis that "over kill" at the Bragg peak will affect the outcome of other biological endpoints.

Dynamic 18F-FET PET in newly diagnosed astrocytic low-grade glioma identifies high-risk patients.

PubMed

Jansen, Nathalie L; Suchorska, Bogdana; Wenter, Vera; Eigenbrod, Sabina; Schmid-Tannwald, Christine; Zwergal, Andreas; Niyazi, Maximilian; Drexler, Mark; Bartenstein, Peter; Schnell, Oliver; Tonn, Jörg-Christian; Thon, Niklas; Kreth, Friedrich-Wilhelm; la Fougère, Christian

2014-02-01

Because the clinical course of low-grade gliomas in the individual adult patient varies considerably and is unpredictable, we investigated the prognostic value of dynamic (18)F-fluorethyltyrosine ((18)F-FET) PET in the early diagnosis of astrocytic low-grade glioma (World Health Organization grade II). Fifty-nine patients with newly diagnosed low-grade glioma and dynamic (18)F-FET PET before histopathologic assessment were retrospectively investigated. (18)F-FET PET analysis comprised a qualitative visual classification of lesions; assessment of the semiquantitative parameters maximal, mean, and total standardized uptake value as ratio to background and biologic tumor volume; and dynamic analysis of intratumoral (18)F-FET uptake over time (increasing vs. decreasing time-activity curves). The correlation between PET parameters and progression-free survival, overall survival, and time to malignant transformation was investigated. (18)F-FET uptake greater than the background level was found in 34 of 59 tumors. Dynamic (18)F-FET uptake analysis was available for 30 of these 34 patients. Increasing and decreasing time-activity curves were found in 18 and 12 patients, respectively. Neither the qualitative factor presence or absence of (18)F-FET uptake nor any of the semiquantitative uptake parameters significantly influenced clinical outcome. In contrast, decreasing time-activity curves in the kinetic analysis were highly prognostic for shorter progression-free survival and time to malignant transformation (P < 0.001). Absence of (18)F-FET uptake in newly diagnosed astrocytic low-grade glioma does not generally indicate an indolent disease course. Among the (18)F-FET-positive gliomas, decreasing time-activity curves in dynamic (18)F-FET PET constitute an unfavorable prognostic factor in astrocytic low-grade glioma and, by identifying high-risk patients, may ease treatment decisions.

Exercises for adolescent idiopathic scoliosis.

PubMed

Romano, Michele; Minozzi, Silvia; Bettany-Saltikov, Josette; Zaina, Fabio; Chockalingam, Nachiappan; Kotwicki, Tomasz; Maier-Hennes, Axel; Negrini, Stefano

2012-08-15

Adolescent idiopathic scoliosis (AIS) is a three-dimensional deformity of the spine . While AIS can progress during growth and cause a surface deformity, it is usually not symptomatic. However, in adulthood, if the final spinal curvature surpasses a certain critical threshold, the risk of health problems and curve progression is increased. The use of scoliosis-specific exercises (SSE) to reduce progression of AIS and postpone or avoid other more invasive treatments is controversial. To evaluate the efficacy of SSE in adolescent patients with AIS. The following databases (up to 30 March 2011) were searched with no language limitations: CENTRAL (The Cochrane Library 2011, issue 2), MEDLINE (from January 1966), EMBASE (from January 1980), CINHAL (from January 1982), SportDiscus (from January 1975), PsycInfo (from January 1887), PEDro (from January 1929). We screened reference lists of articles and also conducted an extensive handsearch of grey literature. Randomised controlled trials and prospective cohort studies with a control group comparing exercises with no treatment, other treatment, surgery, and different types of exercises. Two review authors independently selected studies, assessed risk of bias and extracted data. Two studies (154 participants) were included. There is low quality evidence from one randomised controlled study that exercises as an adjunctive to other conservative treatments increase the efficacy of these treatments (thoracic curve reduced: mean difference (MD) 9.00, (95% confidence interval (CI) 5.47 to 12.53); lumbar curve reduced:MD 8.00, (95% CI 5.08 to 10.92)). There is very low quality evidence from a prospective controlled cohort study that scoliosis-specific exercises structured within an exercise programme can reduce brace prescription (risk ratio (RR) 0.24, (95% CI 0.06 to1.04) as compared to usual physiotherapy (many different kinds of general exercises according to the preferences of the single therapists within different facilities). There is a lack of high quality evidence to recommend the use of SSE for AIS. One very low quality study suggested that these exercises may be more effective than electrostimulation, traction and postural training to avoid scoliosis progression, but better quality research needs to be conducted before the use of SSE can be recommended in clinical practice.

Exercises for adolescent idiopathic scoliosis: a Cochrane systematic review.

PubMed

Romano, Michele; Minozzi, Silvia; Zaina, Fabio; Saltikov, Josette Bettany; Chockalingam, Nachiappan; Kotwicki, Tomasz; Hennes, Axel Maier; Negrini, Stefano

2013-06-15

Systematic review of interventions. To evaluate the efficacy of scoliosis-specific exercise (SSE) in adolescent patients with adolescent idiopathic scoliosis (AIS). AIS is a 3-dimensional deformity of the spine. Although AIS can progress during growth and cause a surface deformity, it is usually not symptomatic. However, in adulthood, if the final spinal curvature surpasses a certain critical threshold, the risk of health problems and curve progression is increased. The use of SSEs to reduce progression of AIS and postpone or avoid other more invasive treatments is controversial. The following databases (up to March 30, 2011) were searched with no language limitations: CENTRAL (The Cochrane Library 2011, issue 2), MEDLINE (from January 1966), EMBASE (from January 1980), CINHAL (from January 1982), SPORTDiscus (from January 1975), PsycINFO (from January 1887), and PEDro (from January 1929). We screened reference lists of articles and conducted an extensive hand search of gray literature. randomized controlled trials and prospective cohort studies with a control group comparing exercises with no treatment, other treatment, surgery, and different types of exercises. Two review authors independently selected studies, assessed risk of bias and extracted data. Two studies (154 participants) were included. There is low-quality evidence from 1 randomized controlled study that exercises as an adjunctive to other conservative treatments to increase the efficacy of these treatments (thoracic curve reduced: mean difference 9.00, [95% confidence interval, 5.47-12.53]; lumbar curve reduced: mean difference 8.00, [95% confidence interval, 5.08-10.92]). There is very low-quality evidence from a prospective controlled cohort study that SSEs structured within an exercise program can reduce brace prescription (risk ratio, 0.24; [95% confidence interval, 0.06-1.04]) as compared with "usual physiotherapy" [many different kinds of general exercises according to the preferences of the single therapists within different facilities]). There is a lack of high-quality evidence to recommend the use of SSE for AIS. One very low-quality study suggested that these exercises may be more effective than electrostimulation, traction, and postural training to avoid scoliosis progression, but better quality research needs to be conducted before the use of SSE can be recommended in clinical practice. 2.

Tests of Behavioral-Economic Assessments of Relative Reinforcer Efficacy: Economic Substitutes

ERIC Educational Resources Information Center

Madden, Gregory J.; Smethells, John R.; Ewan, Eric E.; Hursh, Steven R.

2007-01-01

This experiment was conducted to test predictions of two behavioral-economic approaches to quantifying relative reinforcer efficacy. According to the first of these approaches, characteristics of averaged normalized demand curves may be used to predict progressive-ratio breakpoints and peak responding. The second approach, the demand analysis,…

The past and future of modeling forest dynamics: from growth and yield curves to forest landscape models

Treesearch

Stephen R. Shifley; Hong S. He; Heike Lischke; Wen J. Wang; Wenchi Jin; Eric J. Gustafson; Jonathan R. Thompson; Frank R. Thompson; William D. Dijak; Jian Yang

2017-01-01

Context. Quantitative models of forest dynamics have followed a progression toward methods with increased detail, complexity, and spatial extent. Objectives. We highlight milestones in the development of forest dynamics models and identify future research and application opportunities. Methods. We reviewed...

Tests of Behavioral-Economic Assessments of Relative Reinforcer Efficacy II: Economic Complements

ERIC Educational Resources Information Center

Madden, Gregory J.; Smethells, John R.; Ewan, Eric E.; Hursh, Steven R.

2007-01-01

This experiment was conducted to test the predictions of two behavioral-economic approaches to quantifying relative reinforcer efficacy. The normalized demand analysis suggests that characteristics of averaged normalized demand curves may be used to predict progressive-ratio breakpoints and peak responding. By contrast, the demand analysis holds…

No Pain, No Gain: The Learning Curve in Assessing Collaboratives.

ERIC Educational Resources Information Center

Rendon, Laura I.; Gans, Wendy L.; Calleroz, Mistalene D.

1998-01-01

Presents a case study of an assessment project designed to evaluate the Ford Foundation's Urban Partnership Program (UPP). Discusses UPP's assessment model and theory, and documents the project's yearly progress since its inception in 1992. Details UPP's goals and outcomes in assisting at-risk students. (EMH)

The Lumbar Lordosis in Males and Females, Revisited

PubMed Central

Hay, Ori; Dar, Gali; Abbas, Janan; Stein, Dan; May, Hila; Masharawi, Youssef; Peled, Nathan; Hershkovitz, Israel

2015-01-01

Background Whether differences exist in male and female lumbar lordosis has been debated by researchers who are divided as to the nature of variations in the spinal curve, their origin, reasoning, and implications from a morphological, functional and evolutionary perspective. Evaluation of the spinal curvature is constructive in understanding the evolution of the spine, as well as its pathology, planning of surgical procedures, monitoring its progression and treatment of spinal deformities. The aim of the current study was to revisit the nature of lumbar curve in males and females. Methods Our new automated method uses CT imaging of the spine to measure lumbar curvature in males and females. The curves extracted from 158 individuals were based on the spinal canal, thus avoiding traditional pitfalls of using bone features for curve estimation. The model analysis was carried out on the entire curve, whereby both local and global descriptors were examined in a single framework. Six parameters were calculated: segment length, curve length, curvedness, lordosis peak location, lordosis cranial peak height, and lordosis caudal peak height. Principal Findings Compared to males, the female spine manifested a statistically significant greater curvature, a caudally located lordotic peak, and greater cranial peak height. As caudal peak height is similar for males and females, the illusion of deeper lordosis among females is due partially to the fact that the upper part of the female lumbar curve is positioned more dorsally (more backwardly inclined). Conclusions Males and females manifest different lumbar curve shape, yet similar amount of inward curving (lordosis). The morphological characteristics of the female spine were probably developed to reduce stress on the vertebral elements during pregnancy and nursing. PMID:26301782

Factors in Surgical Decision Making for Thoracolumbar/Lumbar AIS: It's About More Than Just the Curve Magnitude.

PubMed

Souder, Christopher; Newton, Peter O; Shah, Suken A; Lonner, Baron S; Bastrom, Tracey P; Yaszay, Burt

2017-12-01

A retrospective review of prospective data OBJECTIVE:: The purpose of this study was to compare operative and nonoperative patients with similar curve magnitudes to determine motivating factors associated with surgical correction in "smaller" curves. Despite traditional treatment recommendations on major curve angle measurements, many patients with thoracolumbar/lumbar (TH/L) curves of smaller magnitudes are unhappy and desire correction. A prospectively enrolled multicenter adolescent idiopathic scoliosis database was queried. Patients with major TH/L curves <50 degrees and low risk of progression (Risser 3, 4, and 5) were identified and grouped based on their treatment (operative vs. nonoperative). Preoperative demographic, radiographic, Scoliosis Research Society (SRS) outcome scores, and trunk shape values were compared. A total of 126 patients undergoing surgical intervention and 17 patients pursuing nonoperative treatment were analyzed. The average lumbar curve of the operative group was 43 degrees (range, 35 to 49 degrees) and for the nonoperative group was 39 degrees (range, 26 to 49 degrees). The operative group was significantly younger, had larger lumbar major curve angles, lower thoracic to lumbar curve ratio, increased TH/L apical translation, and greater trunk shift (P<0.05). Only lumbar curve (P=0.018, OR=1.19) and trunk shift (P=0.01, OR=3.22) remained significant predictors of surgery in a multivariate regression analysis. SRS scores were significantly lower in the operative group for pain, self-image, function, mental health, and total (P<0.05). When SRS total score was entered into the regression, it was the only significant predictor of surgical intervention (P=0.004, OR=0.03). Many patients with smaller lumbar curves have clinical deformities that are more consistent with larger curves. These smaller curves can produce similar coronal imbalance and trunk shift, with lower SRS domains that may drive patients to seek surgical treatment. What is unclear is the reason for this greater degree of imbalance in this select group of patients and whether the natural history is different for a more balanced TH/L curve. Level II-Prognostic.

Occlusal wear and occlusal condition in a convenience sample of young adults.

PubMed

Van't Spijker, A; Kreulen, C M; Bronkhorst, E M; Creugers, N H J

2015-01-01

To study progression of tooth wear quantitatively in a convenient sample of young adults and to assess possible correlations with occlusal conditions. Twenty-eight dental students participated in a three-year follow up study on tooth wear. Visible wear facets on full arch gypsum casts were assessed using a flatbed scanner and measuring software. Regression analyses were used to assess possible associations between the registered occlusal conditions 'occlusal guidance scheme', 'vertical overbite', 'horizontal overbite', 'depth of sagittal curve', 'canine Angle class relation', 'history of orthodontic treatment', and 'self-reported grinding/clenching' (independent variables) and increase of wear facets (dependent variable). Mean increase in facet surface areas ranged from 1.2 mm2 (premolars, incisors) to 3.4 mm2 (molars); the relative increase ranged from 15% to 23%. Backward regression analysis showed no significant relation for 'group function', 'vertical overbite', 'depth of sagittal curve', 'history of orthodontic treatment' nor 'self-reported clenching. The final multiple linear regression model showed significant associations amongst 'anterior protected articulation' and 'horizontal overbite' and increase of facet surface areas. For all teeth combined, only 'anterior protected articulation' had a significant effect. 'Self reported grinding' did not have a significant effect (p>0.07). In this study 'anterior protected articulation' and 'horizontal overbite', were significantly associated with the progression of tooth wear. Self reported grinding was not significantly associated with progression of tooth wear. Occlusal conditions such as anterior protected articulation and horizontal overbite seem to have an effect on the progression of occlusal tooth wear in this convenient sample of young adults. Copyright © 2014 Elsevier Ltd. All rights reserved.

X-Ray Diffraction Study of the Internal Structure of Supercooled Water

NASA Technical Reports Server (NTRS)

Dorsch, Robert G.; Boyd, Bemrose

1951-01-01

A Bragg X-ray spectrometer equipped with a volume-sensitive Geiger counter and Soller slits and employing filtered molybdenum Ka radiation was used to obtain a set of diffracted intensity curves as a Punction of angle for supercooled water. Diffracted intensity curves in the temperature region of 21 to -16 C were obtained. The minimum between the two main diffraction peaks deepened continuously with lowering temperature, indicating a gradual change in the internal structure of the water. No discontinuity in this trend was noted at the melting point. The internal structure of supercooled water was concluded to become progressively more ice-like as the temperature is lowered.

How to Deal with Interval-Censored Data Practically while Assessing the Progression-Free Survival: A Step-by-Step Guide Using SAS and R Software.

PubMed

Dugué, Audrey Emmanuelle; Pulido, Marina; Chabaud, Sylvie; Belin, Lisa; Gal, Jocelyn

2016-12-01

We describe how to estimate progression-free survival while dealing with interval-censored data in the setting of clinical trials in oncology. Three procedures with SAS and R statistical software are described: one allowing for a nonparametric maximum likelihood estimation of the survival curve using the EM-ICM (Expectation and Maximization-Iterative Convex Minorant) algorithm as described by Wellner and Zhan in 1997; a sensitivity analysis procedure in which the progression time is assigned (i) at the midpoint, (ii) at the upper limit (reflecting the standard analysis when the progression time is assigned at the first radiologic exam showing progressive disease), or (iii) at the lower limit of the censoring interval; and finally, two multiple imputations are described considering a uniform or the nonparametric maximum likelihood estimation (NPMLE) distribution. Clin Cancer Res; 22(23); 5629-35. ©2016 AACR. ©2016 American Association for Cancer Research.

Recovery from nonlinear creep provides a window into physics of polymer glasses

NASA Astrophysics Data System (ADS)

Caruthers, James; Medvedev, Grigori

Creep under constant applied stress is one of the most basic mechanical experiments, where it exhibits extremely rich relaxation behavior for polymer glasses. As many as five distinct stages of nonlinear creep are observed, where the rate of creep dramatically slows down, accelerates and then slows down again. Modeling efforts to-date has primarily focused on predicting the intricacies of the nonlinear creep curve. We argue that as much attention should be paid to the creep recovery response, when the stress is removed. The experimental creep recovery curve is smooth, where the rate of recovery is initially quite rapid and then progressively decreases. In contrast, the majority of the traditional constitutive models predict recovery curves that are much too abrupt. A recently developed stochastic constitutive model that takes into account the dynamic heterogeneity of glasses produces a smooth creep recovery response that is consistent with experiment.

Hearing loss in Usher syndrome type II is nonprogressive.

PubMed

Reisser, Christoph F V; Kimberling, William J; Otterstedde, Christian R

2002-12-01

Usher syndrome is an autosomal recessive disorder characterized by sensorineural hearing loss and progressive visual loss secondary to retinitis pigmentosa. In the literature, a possible progression of the moderate to severe hearing loss in Usher syndrome type II (Usher II) is controversial. We studied the development of the hearing loss of 125 patients with a clinical diagnosis of Usher syndrome type II intraindividually and interindividually by repeatedly performing complete audiological and neuro-otologic examinations. Our data show a very characteristic slope of the hearing curve in all Usher II patients and no clinically relevant progression of the hearing loss over up to 17 years. The subjective impression of a deterioration of the communicative abilities of Usher II patients must therefore be attributed to the progressive visual loss. The patients should be reassured that changes in their hearing abilities are unlikely and should be provided with optimally fitted modern hearing aids.

The potential role of brain asymmetry in the development of adolescent idiopathic scoliosis: a hypothesis.

PubMed

Niesluchowski, W; Dabrowska, A; Kedzior, K; Zagrajek, T

1999-10-01

The size asymmetry of cerebral hemispheres may predispose to head tilt and asymmetric blocking of the zygapophysial joints, potentially leading to the development of compensatory curvatures in the lower segments of the spine. To analyze the effects of spinal manipulation, maintained by an exercise program, on the progression of idiopathic adolescent scoliosis in 2 children aged 6 and 10. The scoliosis found was 16 and 60 degrees. For diagnosis and monitoring of therapy, we recorded qualitative parameters of shoulder asymmetry, axillary line asymmetry, and scapular angle position. Manual treatment consisted of the examinations of all sliding motion in zygapophysial joints and both sacroiliac joints and removing the limitations of the sliding motions according to the method of Karel Lewit. The treatment procedure consisted of 3 or 4 manipulations within 17 months and an exercise program. The manipulation effects were maintained by the exercise program. The exercises were done in 2 or 3 sessions weekly for a year. In both patients we observed that scoliosis decompensation was successfully stopped and the effects of the correction persisted for 10 years. Brain and head asymmetry may be only a transient state, predisposing to asymmetric blocking at the atlanto-occipital level. Removal of blocking may prevent curve progression in children who had adolescent idiopathic scoliosis. The manipulative therapy may also have a promising effect on retarding curve progression when used in skeletally immature patient.

The Kuznets Curve of Education: A Global Perspective on Education Inequalities. CEE DP 116

ERIC Educational Resources Information Center

Morrison, Christian; Murtin, Fabrice

2010-01-01

Education is recognized to be a key factor of economic development, not only giving access to technological progress as emphasized by the Schumpeterian growth theory, but also entailing numerous social externalities such as the demographic transition (Murtin, 2009) or democratization (Murtin and Wacziarg, 2010). If the evolution of world…

A Multilevel Latent Growth Curve Approach to Predicting Student Proficiency

ERIC Educational Resources Information Center

Choi, Kilchan; Goldschmidt, Pete

2012-01-01

Value-added models and growth-based accountability aim to evaluate school's performance based on student growth in learning. The current focus is on linking the results from value-added models to the ones from growth-based accountability systems including Adequate Yearly Progress decisions mandated by No Child Left Behind. We present a new…

EXTENSION OF SELF-MODELING CURVE RESOLUTION TO MIXTURES OF MORE THAN THREE COMPONENTS. PART 3. ATMOSPHERIC AEROSOL DATA SIMULATION STUDIES. (R826238)

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

A comparison of protein profiles of cervical tissue homogenate, exfoliated cells from cervix and serum in normal and cervical malignancy conditions.

PubMed

Bhat, Sujatha; Kartha, Vasudevan Bhaskaran; Rai, Lavanya; Chidangil, Santhosh

2015-01-01

Cervical cancer, the second most common cancer in women, progresses silently over long periods before producing any clinical manifestation. Research in early detection of this condition using proteomic techniques is of very recent origin. We used high-performance liquid chromatography combined with laser-induced fluorescence method in our lab to record the protein profiles of tissue homogenate, cell lysate and serum samples of normal and different stages of malignant conditions of the cervix. Information on protein markers in the protein profiles was derived using various data processing methods including curve resolution. The variations in relative intensities of different peaks with respect to peak height, width and area under the curve from different sample types were compared to get information regarding the concentration of the various proteins and their significance in the induction and metastasis of cervical cancer. The method can be used in diagnosis, follow-up with respect to the progression, remission and effective therapy, in cervical malignancy. © The Author [2014]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

[Early onset scoliosis. What are the options?].

PubMed

Farrington, D M; Tatay-Díaz, A

2013-01-01

The prognosis of children with progressive early onset scoliosis has improved considerably due to recent advances in surgical and non-surgical techniques and the understanding of the importance of preserving the thoracic space. Improvements in existing techniques and development of new methods have considerably improved the management of this condition. Derotational casting can be considered in children with documented progression of a <60° curve without previous surgical treatment. Both single and dual growing rods are effective, but the latter seem to offer better results. Hybrid constructs may be a better option in children who require a low-profile proximal anchor. The vertical expandable prosthetic titanium rib (VEPTR(®)) appears to be beneficial for patients with congenital scoliosis and fused ribs, and thoracic Insufficiency Syndrome. Children with medical comorbidities who may not tolerate repeated lengthenings should be considered for Shilla or Luque Trolley technique. Growth modulation using shape memory alloy staples or other tethers seem promising for mild curves, although more research is required to define their precise indications. Copyright © 2013 SECOT. Published by Elsevier Espana. All rights reserved.

Predictive value of modeled AUC(AFP-hCG), a dynamic kinetic parameter characterizing serum tumor marker decline in patients with nonseminomatous germ cell tumor.

PubMed

You, Benoit; Fronton, Ludivine; Boyle, Helen; Droz, Jean-Pierre; Girard, Pascal; Tranchand, Brigitte; Ribba, Benjamin; Tod, Michel; Chabaud, Sylvie; Coquelin, Henri; Fléchon, Aude

2010-08-01

The early decline profile of alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG) in patients with nonseminomatous germ cell tumors (NSGCT) treated with chemotherapy may be related to the risk of relapse. We assessed the predictive values of areas under the curve of hCG (AUC(hCG)) and AFP (AUC(AFP)) of modeled concentration-time equations on progression-free survival (PFS). Single-center retrospective analysis of hCG and AFP time-points from 65 patients with IGCCCG intermediate-poor risk NSGCT treated with 4 cycles of bleomycin-etoposide-cisplatin (BEP). To determine AUC(hCG) and AUC(AFP) for D0-D42, AUCs for D0-D7 were calculated using the trapezoid rule and AUCs for D7-D42 were calculated using the mathematic integrals of equations modeled with NONMEM. Combining AUC(AFP) and AUC(hCG) enabled us to define 2 predictive groups: namely, patients with favorable and unfavorable AUC(AFP-hCG). Survival analyses and ROC curves assessed the predictive values of AUC(AFP-hCG) groups regarding progression-free survival (PFS) and compared them with those of half-life (HL) and time-to-normalization (TTN). Mono-exponential models best fit the patterns of marker decreases. Patients with a favorable AUC(AFP-hCG) had a significantly better PFS (100% vs 71.5%, P = .014). ROC curves confirmed the encouraging predictive accuracy of AUC(AFP-hCG) against HL or TTN regarding progression risk (ROC AUCs = 79.6 vs 71.9 and 70.2 respectively). Because of the large number of patients with missing data, multivariate analysis could not be performed. AUC(AFP-hCG) is a dynamic parameter characterizing tumor marker decline in patients with NSGCT during BEP treatment. Its value as a promising predictive factor should be validated. Copyright 2010 Elsevier Inc. All rights reserved.

Atherosclerotic renovascular disease among hypertensive adults

PubMed Central

Davis, Ross P.; Pearce, Jeffrey D.; Craven, Timothy E.; Moore, Phillip S.; Edwards, Matthew S.; Godshall, Christopher J.; Hansen, Kimberley J.

2010-01-01

Purpose Ths report describes the change in atherosclerotic renovascular disease (AS-RVD) among hypertensive adults referred for renal duplex sonography (RDS) scan. Methods From Oct 1993 through July 2008, 20,994 patients had RDS at our center. A total of 434 hypertensive patients with two or more RDS exams without intervention comprised the study cohort. Patient demographics (blood pressures, medications, serum creatinine levels, and data from RDS) were collected. Analyses of longitudinal changes in Doppler scan parameters, blood pressures, and renal function were performed by fitting linear growth-curve models. After confirming the linearity of change in Doppler scan parameters among patients with variable number of studies, estimates of mean slopes were calculated using maximum likelihood techniques. For changes in renal function, quadratic growth curves were required to describe longitudinal change. Results A total of 434 subjects (212 men [49%] and 222 women [51%]; mean age, 64.6 ± 12.2 years) provided 1351 studies (mean, 3.2 ± 2.4; range, 2 to 18) for 863 kidneys over a mean follow-up of 34.4 ± 25.1 months. At baseline, 20.6% of kidneys demonstrated hemodynamically significant stenosis. On follow-up, 72 kidneys (9.1%) demonstrated anatomic progression of disease. A total of 54 kidneys (6.9%) progressed to significant stenosis and 18 (2.3%) progressed to occlusion. Controlling for progression of disease, baseline renal artery status demonstrated a strong association with baseline kidney length (P = .0006). Significant annualized change in renal length was observed (cm change/year ± standard error of the mean [SEM]: 0.042 ± 0.011; P = .0002) among both kidneys with and without critical disease at baseline, however, decline in length was significantly greater among kidneys exhibiting progression of renovascular disease (−0.152 ± 0.028 cm/year; comparison of slopes between groups P = .0005). In the absence of progression, the presence or absence of critical renal artery stenosis at baseline did not affect the rate of decline in renal length. Fitted models for the natural log transform of serum creatinine demonstrated a significant increase during follow-up (P < .0001). No association was observed between change in serum creatinine and baseline renovascular disease status, or its progression. Conclusion A total of 32% of hypertensive adults referred for RDS demonstrated hemodynamically significant renal artery stenosis. Regardless of the presence or absence of baseline disease, a small percentage of patients demonstrated anatomic progression of AS-RVD. A total of 9.1% demonstrated anatomic progression and 2.3% progressed to occlusion. Although anatomic progression of AS-RVD was associated with an increased rate of decline in renal length, progression did not predict a decline in excretory renal function. Intervention for AS-RVD should be selective and reserved for strict indications. PMID:19700093

What's New in Congenital Scoliosis?

PubMed

Pahys, Joshua M; Guille, James T

2018-03-01

Congenital scoliosis is a failure of vertebral formation, segmentation, or a combination of the 2 arising from abnormal vertebral development during weeks 4 to 6 of gestation. The associated spinal deformity can be of varying severity and result in a stable or progressive deformity based on the type and location of the anomalous vertebra(e). Bracing for congenital scoliosis is rarely indicated, while recent reports have demonstrated the utility of serial derotational casting for longer curves with multiple anomalous vertebrae as an effective "time buying strategy" to delay the need for surgery. Earlier hemivertebra excision and short-segment posterior spinal fusion have been advocated to prevent future curve progression of the deformity and/or the development of large compensatory curves. It has been shown in recent long-term follow-up studies that growth rates of the vertebral body and spinal canal are not as dramatically affected by pedicle screw instrumentation at a young age as once thought. Growth friendly surgery with either spine-based or rib-based anchors has demonstrated good results with curve correction while maintaining spinal growth. Rib-based anchors are typically more commonly indicated in the setting of chest wall abnormalities and/or when spinal anatomy precludes placement of spinal instrumentation. Recently, magnetically controlled growing rods have shown promising results in several studies that include a small subset of congenital scoliosis cases. A literature search was performed to identify existing studies related to the treatment of congenital scoliosis published from January 1, 2005 to June 1, 2016. Databases included PubMed, Medline, and the Cochrane Library. The search was limited to English articles and yielded 36 papers. This project was initiated by the Pediatric Orthopaedic Society of North America Publications Committee and was reviewed and approved by the Pediatric Orthopaedic Society of North America Presidential Line. A total of 36 papers were selected for review based upon new findings. Classic manuscripts on congenital scoliosis are also included to provide sufficient background information. Congenital scoliosis represents a wide range of pathology from the simple, stable hemivertebra to the complex, progressive spinal deformity with chest wall abnormalities and associated cardiac, renal, and neural axis anomalies. This paper reviews the natural history and associated anomalies with congenital scoliosis as well as the most up-to-date classification schemes and various treatment options for the care of this challenging patient population. Level 5.

The effect of the inner-hair-cell mediated transduction on the shape of neural tuning curves

NASA Astrophysics Data System (ADS)

Altoè, Alessandro; Pulkki, Ville; Verhulst, Sarah

2018-05-01

The inner hair cells of the mammalian cochlea transform the vibrations of their stereocilia into releases of neurotransmitter at the ribbon synapses, thereby controlling the activity of the afferent auditory fibers. The mechanical-to-neural transduction is a highly nonlinear process and it introduces differences between the frequency-tuning of the stereocilia and that of the afferent fibers. Using a computational model of the inner hair cell that is based on in vitro data, we estimated that smaller vibrations of the stereocilia are necessary to drive the afferent fibers above threshold at low (≤0.5 kHz) than at high (≥4 kHz) driving frequencies. In the base of the cochlea, the transduction process affects the low-frequency tails of neural tuning curves. In particular, it introduces differences between the frequency-tuning of the stereocilia and that of the auditory fibers resembling those between basilar membrane velocity and auditory fibers tuning curves in the chinchilla base. For units with a characteristic frequency between 1 and 4 kHz, the transduction process yields shallower neural than stereocilia tuning curves as the characteristic frequency decreases. This study proposes that transduction contributes to the progressive broadening of neural tuning curves from the base to the apex.

Serial Derotational Casting in Idiopathic and Non-Idiopathic Progressive Early-Onset Scoliosis.

PubMed

Gussous, Yazeed M; Tarima, Sergey; Zhao, Shi; Khan, Safdar; Caudill, Angela; Sturm, Peter; Hammerberg, Kim W

2015-05-01

Serial derotational casting has been used as a definitive treatment or as delaying strategy in progressive idiopathic (IS) and non-idiopathic (NIS) early-onset scoliosis (EOS). Retrospective chart and radiographic review of patients who underwent serial casting for progressive EOS between 2005 and 2012 at a single institution. A total of 74 consecutive patients entered serial cast treatment. Twenty-eight were currently being casted, 30 completed cast treatment and were converted to thoracolumbosacral orthosis (TLSO), 9 were treated surgically, 6 were lost to follow-up, and 1 had no further treatment. The researchers diagnosed IS in 41 patients; 33 had NIS. At presentation the IS group had an average Cobb angle (CA) of 49° and a rib vertebral angle difference (RVAD) of 37°. The NIS group had a CA of 51° (p = .69) and RVAD of 37° (p = .94). In patients currently being casted, 19 IS patients had a decreased CA, from 47° to 27°. The 9 NIS patients had a decreased CA, from 62° to 57° (p = .0002). Cobb angle improvement was significantly better in IS (p = .0005). In the TLSO group the 17 IS patients had a decreased average CA, from 46° to 18°, after serial casting and the 13 NIS patients decreased CA from 42° to 32°. Patients with IS had better improvement in CA than the NIS group (p < .001). At last follow-up, this was reduced to 11° in the IS group and maintained at 32° in the NIS. In the IS group, 5 of 41 patients were converted to growth constructs, and 4 of 26 in the NIS group. Casting initiated before age 2 years yielded better curve correction for IS (p < .01) compared with NIS. Progressive idiopathic scoliosis patients had better curve correction with casting than NIS patients. Casting in IS patients before age 24 months yielded better curve correction. Patients who required surgery had a higher age and Cobb angle at presentation than those who transitioned to a TLSO. The surgical group was observed for a similar duration of time and there was no significant statistical difference. Although RVAD is a predictor of progression in infantile IS, it did not show a predictive value in the response to casting of either the IS or NIS groups. Copyright © 2015 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.

The S-curve for forecasting waste generation in construction projects.

PubMed

Lu, Weisheng; Peng, Yi; Chen, Xi; Skitmore, Martin; Zhang, Xiaoling

2016-10-01

Forecasting construction waste generation is the yardstick of any effort by policy-makers, researchers, practitioners and the like to manage construction and demolition (C&D) waste. This paper develops and tests an S-curve model to indicate accumulative waste generation as a project progresses. Using 37,148 disposal records generated from 138 building projects in Hong Kong in four consecutive years from January 2011 to June 2015, a wide range of potential S-curve models are examined, and as a result, the formula that best fits the historical data set is found. The S-curve model is then further linked to project characteristics using artificial neural networks (ANNs) so that it can be used to forecast waste generation in future construction projects. It was found that, among the S-curve models, cumulative logistic distribution is the best formula to fit the historical data. Meanwhile, contract sum, location, public-private nature, and duration can be used to forecast construction waste generation. The study provides contractors with not only an S-curve model to forecast overall waste generation before a project commences, but also with a detailed baseline to benchmark and manage waste during the course of construction. The major contribution of this paper is to the body of knowledge in the field of construction waste generation forecasting. By examining it with an S-curve model, the study elevates construction waste management to a level equivalent to project cost management where the model has already been readily accepted as a standard tool. Copyright © 2016 Elsevier Ltd. All rights reserved.

Multiple cervical hemivertebra resection and staged thoracic pedicle subtraction osteotomy in the treatment of complicated congenital scoliosis.

PubMed

Zhuang, Qianyu; Zhang, Jianguo; Wang, Shengru; Guo, Jianwei; Qiu, Guixing

2016-05-01

To present our experience of staged correction with multiple cervical hemivertebra resection and thoracic pedicle subtraction osteotomy (PSO) treating a rare and complicated congenital scoliosis. A 14-year-old male presented with progressive torticollis and spine deformity. The malformation developed since birth, and back pain after long-time sitting or exercise arose since 6 months before, which was unsuccessfully treated by physiotherapy. X-ray showed a right cervical curve of 60° and a left compensatory thoracic curve of 90°. Three-dimensional computed tomography (3-D CT) scan revealed three semi-segmented hemivertebrae (C4, C5 and C6) on the right side. Based on our staged strategy, the three consecutive cervical hemivertebrae, as the major pathology causing the deformity, were firstly resected by the combined posterior and anterior approach. Six months later, T6 PSO osteotomy was used to correct the structural compensatory thoracic curve. The cervical curve was reduced to 23° while the thoracic curve to 60° after the first-stage surgery, and the thoracic curve was further reduced to 30° after the second-stage surgery. The radiograph at 5-year follow-up showed that both the coronal and sagittal balance were well restored and stabilized, with the occipital tilt reduced from 12° to 0°. Our strategy may provide an option for similar cases with multiple consecutive cervical hemivertebrae and a large structural compensatory thoracic curve, which proved to achieve excellent correction in both the coronal and sagittal planes with acceptable neurologic risk.

Patterns and predictors of skin score change in early diffuse systemic sclerosis from the European Scleroderma Observational Study.

PubMed

Herrick, Ariane L; Peytrignet, Sebastien; Lunt, Mark; Pan, Xiaoyan; Hesselstrand, Roger; Mouthon, Luc; Silman, Alan J; Dinsdale, Graham; Brown, Edith; Czirják, László; Distler, Jörg H W; Distler, Oliver; Fligelstone, Kim; Gregory, William J; Ochiel, Rachel; Vonk, Madelon C; Ancuţa, Codrina; Ong, Voon H; Farge, Dominique; Hudson, Marie; Matucci-Cerinic, Marco; Balbir-Gurman, Alexandra; Midtvedt, Øyvind; Jobanputra, Paresh; Jordan, Alison C; Stevens, Wendy; Moinzadeh, Pia; Hall, Frances C; Agard, Christian; Anderson, Marina E; Diot, Elisabeth; Madhok, Rajan; Akil, Mohammed; Buch, Maya H; Chung, Lorinda; Damjanov, Nemanja S; Gunawardena, Harsha; Lanyon, Peter; Ahmad, Yasmeen; Chakravarty, Kuntal; Jacobsen, Søren; MacGregor, Alexander J; McHugh, Neil; Müller-Ladner, Ulf; Riemekasten, Gabriela; Becker, Michael; Roddy, Janet; Carreira, Patricia E; Fauchais, Anne Laure; Hachulla, Eric; Hamilton, Jennifer; İnanç, Murat; McLaren, John S; van Laar, Jacob M; Pathare, Sanjay; Proudman, Susanna M; Rudin, Anna; Sahhar, Joanne; Coppere, Brigitte; Serratrice, Christine; Sheeran, Tom; Veale, Douglas J; Grange, Claire; Trad, Georges-Selim; Denton, Christopher P

2018-04-01

Our aim was to use the opportunity provided by the European Scleroderma Observational Study to (1) identify and describe those patients with early diffuse cutaneous systemic sclerosis (dcSSc) with progressive skin thickness, and (2) derive prediction models for progression over 12 months, to inform future randomised controlled trials (RCTs). The modified Rodnan skin score (mRSS) was recorded every 3 months in 326 patients. 'Progressors' were defined as those experiencing a 5-unit and 25% increase in mRSS score over 12 months (±3 months). Logistic models were fitted to predict progression and, using receiver operating characteristic (ROC) curves, were compared on the basis of the area under curve (AUC), accuracy and positive predictive value (PPV). 66 patients (22.5%) progressed, 227 (77.5%) did not (33 could not have their status assessed due to insufficient data). Progressors had shorter disease duration (median 8.1 vs 12.6 months, P=0.001) and lower mRSS (median 19 vs 21 units, P=0.030) than non-progressors. Skin score was highest, and peaked earliest, in the anti-RNA polymerase III (Pol3+) subgroup (n=50). A first predictive model (including mRSS, duration of skin thickening and their interaction) had an accuracy of 60.9%, AUC of 0.666 and PPV of 33.8%. By adding a variable for Pol3 positivity, the model reached an accuracy of 71%, AUC of 0.711 and PPV of 41%. Two prediction models for progressive skin thickening were derived, for use both in clinical practice and for cohort enrichment in RCTs. These models will inform recruitment into the many clinical trials of dcSSc projected for the coming years. NCT02339441. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Risk of progression to diabetes from prediabetes defined by HbA1c or fasting plasma glucose criteria in Koreans.

PubMed

Kim, Chul-Hee; Kim, Hong-Kyu; Kim, Eun-Hee; Bae, Sung-Jin; Choe, Jaewon; Park, Joong-Yeol

2016-08-01

To examine the abilities of HbA1c and fasting plasma glucose (FPG) criteria predicting 5-year progression rate to diabetes in Korean adults with prediabetes. Participants included 17,971 Koreans (aged 20-79years) who underwent routine medical check-ups at a mean interval of 5.2years (3.1-6.7years). Prediabetes was defined as FPG 5.6-6.9mmol/l or HbA1c 5.7-6.4% (39-46mmol/mol). Incident diabetes was defined as FPG⩾7.0mmol/l, HbA1c⩾6.5% (48mmol/mol), or initiation of antidiabetic medications. At baseline, the prevalence of prediabetes was 30.6% (n=5495) by FPG and 20.4% (n=3664) by HbA1c criteria. The 5-year progression rate to diabetes was significantly higher in prediabetes identified by HbA1c than by FPG tests (14.7% vs. 10.4%, P<0.001). Of individuals diagnosed with prediabetes by only one test, those by HbA1c alone had a higher risk of progression to diabetes than those diagnosed by FPG alone (6.0% vs. 3.9%, P<0.001). Receiver operating characteristic curve analysis showed that area under the curve was greater for HbA1c (0.855, 95% CI 0.840-0.870) than for FPG (0.830, 0.813-0.846) (P=0.016). After adjustment for conventional risk factors, the odds ratio (OR) of developing diabetes was higher in participants with prediabetes identified by HbA1c (OR 9.91, 8.24-11.9) than by FPG (OR 7.29, 5.97-8.89) (P=0.026). Although fewer individuals with prediabetes were identified by HbA1c than by FPG criteria, the ability to predict progression to diabetes was stronger for HbA1c than for FPG in Koreans. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Differences in the accommodation stimulus response curves of adult myopes and emmetropes: a summary and update.

PubMed

Schmid, Katrina L; Strang, Niall C

2015-11-01

To provide a summary of the classic paper "Differences in the accommodation stimulus response curves of adult myopes and emmetropes" published in Ophthalmic and Physiological Optics in 1998 and to provide an update on the topic of accommodation errors in myopia. The accommodation responses of 33 participants (10 emmetropes, 11 early onset myopes and 12 late onset myopes) aged 18-31 years were measured using the Canon Autoref R-1 free space autorefractor using three methods to vary the accommodation demand: decreasing distance (4 m to 0.25 cm), negative lenses (0 to -4 D at 4 m) and positive lenses (+4 to 0 D at 0.25 m). We observed that the greatest accommodation errors occurred for the negative lens method whereas minimal errors were observed using positive lenses. Adult progressing myopes had greater lags of accommodation than stable myopes at higher demands induced by negative lenses. Progressing myopes had shallower response gradients than the emmetropes and stable myopes; however the reduced gradient was much less than that observed in children using similar methods. This paper has been often cited as evidence that accommodation responses at near may be primarily reduced in adults with progressing myopia and not in stable myopes and/or that challenging accommodation stimuli (negative lenses with monocular viewing) are required to generate larger accommodation errors. As an analogy, animals reared with hyperopic errors develop axial elongation and myopia. Retinal defocus signals are presumably passed to the retinal pigment epithelium and choroid and then ultimately the sclera to modify eye length. A number of lens treatments that act to slow myopia progression may partially work through reducing accommodation errors. © 2015 The Authors Ophthalmic & Physiological Optics © 2015 The College of Optometrists.

Derivation of genetic biomarkers for cancer risk stratification in Barrett's oesophagus: a prospective cohort study

PubMed Central

Timmer, Margriet R.; Martinez, Pierre; Lau, Chiu T.; Westra, Wytske M.; Calpe, Silvia; Rygiel, Agnieszka M.; Rosmolen, Wilda D.; Meijer, Sybren L.; ten Kate, Fiebo J.W.; Dijkgraaf, Marcel G.W.; Mallant-Hent, Rosalie C.; Naber, Anton H.J.; van Oijen, Arnoud H.A.M.; Baak, Lubbertus C.; Scholten, Pieter; Böhmer, Clarisse J.M.; Fockens, Paul; Maley, Carlo C.; Graham, Trevor A.; Bergman, Jacques J.G.H.M.; Krishnadath, Kausilia K.

2016-01-01

Objective The risk of developing adenocarcinoma in non-dysplastic Barrett's oesophagus is low and difficult to predict. Accurate tools for risk stratification are needed to increase the efficiency of surveillance. We aimed to develop a prediction model for progression using clinical variables and genetic markers. Methods In a prospective cohort of patients with non-dysplastic Barrett's oesophagus, we evaluated six molecular markers: p16, p53, Her-2/neu, 20q, MYC, and aneusomy by DNA fluorescence in situ hybridisation on brush cytology specimens. Primary study outcomes were the development of high-grade dysplasia or oesophageal adenocarcinoma. The most predictive clinical variables and markers were determined using Cox proportional-hazards models, receiver-operating-characteristic curves and a leave-one-out analysis. Results A total of 428 patients participated (345 men; median age 60 years) with a cumulative follow-up of 2019 patient-years (median 45 months per patient). Of these patients, 22 progressed; nine developed high-grade dysplasia and 13 oesophageal adenocarcinoma. The clinical variables, age and circumferential Barrett's length, and the markers, p16 loss, MYC gain, and aneusomy, were significantly associated with progression on univariate analysis. We defined an ‘Abnormal Marker Count’ that counted abnormalities in p16, MYC and aneusomy, which significantly improved risk prediction beyond using just age and Barrett's length. In multivariate analysis, these three factors identified a high-risk group with an 8.7-fold (95% CI, 2.6 to 29.8) increased hazard ratio compared with the low-risk group, with an area under the curve of 0.76 (95% CI, 0.66 to 0.86). Conclusion A prediction model based on age, Barrett's length, and the markers p16, MYC, and aneusomy determines progression risk in non-dysplastic Barrett's oesophagus. PMID:26104750

Function follows form: combining nanoimprint and inkjet printing

NASA Astrophysics Data System (ADS)

Muehlberger, M.; Haslinger, M. J.; Kurzmann, J.; Ikeda, M.; Fuchsbauer, A.; Faury, T.; Koepplmayr, T.; Ausserhuber, H.; Kastner, J.; Woegerer, C.; Fechtig, D.

2017-06-01

We are investigating the possibilities and the technical requirements to do nanopatterning on arbitrary curved surfaces. This is done considering the opportunities and possibilities of additive manufacturing. One of the key elements is the necessity to deposit material in well-defined areas of various complex 3D objects. In order to achieve this we are developing a robot-based inkjet printing. We report on our progress with this respect and also on our efforts to perform nanoimprinting on curved, possibly 3D-printed objects using materials that can be deposited by inkjet printing. In the framework of this article, we provide an overview over our current status, the challenges and an outlook.

Investigation of Composite Structures

NASA Technical Reports Server (NTRS)

Hyer, Michael W.

2000-01-01

This final report consists of a compilation of four separate written documents, three dealing with the response and failure of elliptical composite cylinders to an internal pressure load, and the fourth dealing with the influence of manufacturing imperfections in curved composite panels. The three focused on elliptical cylinders consist of the following: 1 - A paper entitled "Progressive Failure Analysis of Internally Pressurized Elliptical Composite Cylinders," 2 - A paper entitled "Influence of Geometric Nonlinearities on the Response and Failure of Internally Pressurized Elliptical Composite Cylinders," and 3 - A report entitled "Response and Failure of Internally Pressurized Elliptical Composite Cyclinders." The document which deals with the influence of manufacturing imperfections is a paper entitled "Manufacturing Distortions of Curved Composite Panels."

Pedagogically Speaking: Teaching outside Pandora's Box

ERIC Educational Resources Information Center

Roffman, Deborah M.

2010-01-01

Even at the dawn of the 21st century, the sexual education of children in America is controlled by attitudes and myths about sexual learning that, in reality, date back hundreds of years. And despite the strong, vibrant, and progressive traditions, many independent schools also remain well behind the curve on this vital aspect of children's lives.…

Cost reductions in nickel-hydrogen battery

NASA Technical Reports Server (NTRS)

Beauchamp, Richard L.; Sindorf, Jack F.

1987-01-01

Significant progress was made toward the development of a commercially marketable hydrogen nickel oxide battery. The costs projected for this battery are remarkably low when one considers where the learning curve is for commercialization of this system. Further developmental efforts on this project are warranted as the H2/NiO battery is already cost competitive with other battery systems.

Slow Dangerous Curve: Scoliosis and Posture Screening Handbook. Revised Edition.

ERIC Educational Resources Information Center

Tenney, Horace K., III; And Others

The yearly screening process to detect scoliosis (curvature of the spine) and poor posture in girls 10 to 14 and boys 13 to 14 is discussed. The purpose of the program is to detect deformities in their earliest stages to prevent progression. Photographs are interspersed with text on suggestions for planning the screening program, clothing, setting…

Mentorship, learning curves, and balance.

PubMed

Cohen, Meryl S; Jacobs, Jeffrey P; Quintessenza, James A; Chai, Paul J; Lindberg, Harald L; Dickey, Jamie; Ungerleider, Ross M

2007-09-01

Professionals working in the arena of health care face a variety of challenges as their careers evolve and develop. In this review, we analyze the role of mentorship, learning curves, and balance in overcoming challenges that all such professionals are likely to encounter. These challenges can exist both in professional and personal life. As any professional involved in health care matures, complex professional skills must be mastered, and new professional skills must be acquired. These skills are both technical and judgmental. In most circumstances, these skills must be learned. In 2007, despite the continued need for obtaining new knowledge and learning new skills, the professional and public tolerance for a "learning curve" is much less than in previous decades. Mentorship is the key to success in these endeavours. The success of mentorship is two-sided, with responsibilities for both the mentor and the mentee. The benefits of this relationship must be bidirectional. It is the responsibility of both the student and the mentor to assure this bidirectional exchange of benefit. This relationship requires time, patience, dedication, and to some degree selflessness. This mentorship will ultimately be the best tool for mastering complex professional skills and maturing through various learning curves. Professional mentorship also requires that mentors identify and explicitly teach their mentees the relational skills and abilities inherent in learning the management of the triad of self, relationships with others, and professional responsibilities.Up to two decades ago, a learning curve was tolerated, and even expected, while professionals involved in healthcare developed the techniques that allowed for the treatment of previously untreatable diseases. Outcomes have now improved to the point that this type of learning curve is no longer acceptable to the public. Still, professionals must learn to perform and develop independence and confidence. The responsibility to meet this challenge without a painful learning curve belongs to both the younger professionals, who must progress through the learning curve, and the more mature professionals who must create an appropriate environment for learning. In addition to mentorship, the detailed tracking of outcomes is an essential tool for mastering any learning curve. It is crucial to utilize a detailed database to track outcomes, to learn, and to protect both yourself and your patients. It is our professional responsibility to engage in self-evaluation, in part employing voluntary sharing of data. For cardiac surgical subspecialties, the databases now existing for The European Association for CardioThoracic Surgery and The Society of Thoracic Surgeons represent the ideal tool for monitoring outcomes. Evolving initiatives in the fields of paediatric cardiology, paediatric critical care, and paediatric cardiac anaesthesia will play similar roles.A variety of professional and personal challenges must be met by all those working in health care. The acquisition of learned skills, and the use of special tools, will facilitate the process of conquering these challenges. Choosing appropriate role models and mentors can help progression through any learning curve in a controlled and protected fashion. Professional and personal satisfaction are both necessities. Finding the satisfactory balance between work and home life is difficult, but possible with the right tools, organization skills, and support system at work and at home. The concepts of mentorship, learning curves and balance cannot be underappreciated.

A novel model of magnetorheological damper with hysteresis division

NASA Astrophysics Data System (ADS)

Yu, Jianqiang; Dong, Xiaomin; Zhang, Zonglun

2017-10-01

Due to the complex nonlinearity of magnetorheological (MR) behavior, the modeling of MR dampers is a challenge. A simple and effective model of MR damper remains a work in progress. A novel model of MR damper is proposed with force-velocity hysteresis division method in this study. A typical hysteresis loop of MR damper can be simply divided into two novel curves with the division idea. One is the backbone curve and the other is the branch curve. The exponential-family functions which capturing the characteristics of the two curves can simplify the model and improve the identification efficiency. To illustrate and validate the novel phenomenological model with hysteresis division idea, a dual-end MR damper is designed and tested. Based on the experimental data, the characteristics of the novel curves are investigated. To simplify the parameters identification and obtain the reversibility, the maximum force part, the non-dimensional backbone part and the non-dimensional branch part are derived from the two curves. The maximum force part and the non-dimensional part are in multiplication type add-rule. The maximum force part is dependent on the current and maximum velocity. The non-dominated sorting genetic algorithm II (NSGA II) based on the design of experiments (DOE) is employed to identify the parameters of the normalized shape functions. Comparative analysis is conducted based on the identification results. The analysis shows that the novel model with few identification parameters has higher accuracy and better predictive ability.

Detorsion night-time bracing for the treatment of early onset idiopathic scoliosis.

PubMed

Moreau, S; Lonjon, G; Mazda, K; Ilharreborde, B

2014-12-01

Management for early onset scoliosis has recently changed, with the development of new surgical procedures. However, multiple surgeries are often required and high complication rates are still reported. Conservative management remains an alternative, serial casting achieving excellent results in young children. Better compliance and improvement over natural history have been reported with night-time bracing in adolescent idiopathic scoliosis (AIS), but this treatment has never been reported in early onset idiopathic scoliosis (EIOS). All patients treated for progressive EOIS by detorsion night-time bracing (DNB), and meeting the Scoliosis Research Society (SRS) criteria for brace studies were reviewed. Recommendations were given to wear the DNB 8h/night and no restriction was given regarding sports activities. Radiological parameters were compared between referral and latest follow-up. Based on the SRS criteria defined for AIS, a similar classification was used as follows to analyze the course of the curves: success group: patients with a progression of 5° or less; unsuccess group (progression or failure): patients with a progression>5°, patients with curves exceeding 45° at maturity, or who have had recommendation for/undergone surgery, or patients who changed orthopaedic treatment, or who were lost to follow-up. Thirty-three patients were included (21 girls and 12 boys), with a median Cobb angle of 31° (Q1-Q3: 22-40). Age at brace initiation averaged 50months (Q1-Q3: 25-60). Median follow-up was 102-months (Q1-Q3: 63-125). Fifteen patients (45.5%) had reached skeletal maturity at last follow-up. The success rate was 67% (22 patients), with a median Cobb angle reduction of 15° (P<0.001). Four patients stopped DNB due to an important regression. Eleven patients were in the unsuccessful group (33%). Only one had surgery. All patients remained balanced in the frontal plane and normokyphotic. Initial curve magnitude and age at brace initiation appeared to be important prognostic factors. DNB is an effective conservative treatment, which can be considered a delaying tactic in the management of EOIS. This brace offers potential psychosocial and compliance benefits, and allows unconstrained spinal and chest wall growth, resulting in normokyphosis at maturity. Therapeutic study (retrospective consecutive case series): Level IV. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

A Century of Enzyme Kinetic Analysis, 1913 to 2013

PubMed Central

Johnson, Kenneth A.

2013-01-01

This review traces the history and logical progression of methods for quantitative analysis of enzyme kinetics from the 1913 Michaelis and Menten paper to the application of modern computational methods today. Following a brief review of methods for fitting steady state kinetic data, modern methods are highlighted for fitting full progress curve kinetics based upon numerical integration of rate equations, including a re-analysis of the original Michaelis-Menten full time course kinetic data. Finally, several illustrations of modern transient state kinetic methods of analysis are shown which enable the elucidation of reactions occurring at the active sites of enzymes in order to relate structure and function. PMID:23850893

Estimating long-term multivariate progression from short-term data.

PubMed

Donohue, Michael C; Jacqmin-Gadda, Hélène; Le Goff, Mélanie; Thomas, Ronald G; Raman, Rema; Gamst, Anthony C; Beckett, Laurel A; Jack, Clifford R; Weiner, Michael W; Dartigues, Jean-François; Aisen, Paul S

2014-10-01

Diseases that progress slowly are often studied by observing cohorts at different stages of disease for short periods of time. The Alzheimer's Disease Neuroimaging Initiative (ADNI) follows elders with various degrees of cognitive impairment, from normal to impaired. The study includes a rich panel of novel cognitive tests, biomarkers, and brain images collected every 6 months for as long as 6 years. The relative timing of the observations with respect to disease pathology is unknown. We propose a general semiparametric model and iterative estimation procedure to estimate simultaneously the pathological timing and long-term growth curves. The resulting estimates of long-term progression are fine-tuned using cognitive trajectories derived from the long-term "Personnes Agées Quid" study. We demonstrate with simulations that the method can recover long-term disease trends from short-term observations. The method also estimates temporal ordering of individuals with respect to disease pathology, providing subject-specific prognostic estimates of the time until onset of symptoms. When the method is applied to ADNI data, the estimated growth curves are in general agreement with prevailing theories of the Alzheimer's disease cascade. Other data sets with common outcome measures can be combined using the proposed algorithm. Software to fit the model and reproduce results with the statistical software R is available as the grace package. ADNI data can be downloaded from the Laboratory of NeuroImaging. Copyright © 2014 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Anthropometric evaluation of pediatric patients with nonprogressive chronic encephalopathy according to different methods of classification☆

PubMed Central

Teixeira, Jéssica Socas; Gomes, Mirian Martins

2014-01-01

Objective: To perform anthropometric assessment of patients with quadriplegic, chronic non-progressive encephalopathy, comparing two distinct references of nutritional classification and to compare the estimated height to the length measured by stadiometer. Method: Cross-sectional study including 0-3-year children with quadriplegic chronic non-progressive encephalopathy in secondary public hospital. Length, weight, arm circumference, triceps skinfold and knee height were measured. The arm muscle circumference and estimated height were calculated. The following relations were evaluated: weight-for-age, length-for-age and weight-for-length, using as reference the charts of the World Health Organization (WHO) and those proposed by Krick et al. Results: Fourteen children with a mean age of 21 months were evaluated. Assessment of anthropometric indicators showed significant difference between the two classification methods to assess nutritional indicators length/age (p=0.014), weight/age (p=0.014) and weight/length (p=0.001). There was significant correlation between measured length and estimated height (r=0.796, p=0.001). Evaluation of arm circumference and triceps skinfold showed that most patients presented some degree of malnutrition. According to arm muscle circumference, most were eutrophic. Conclusions: Specific curves for children with chronic non-progressive encephalopathy appear to underestimate malnutrition when one takes into account indicators involving weight. Curves developed for healthy children can be a good option for clinical practice and weight-for-length indicator and body composition measurements should be considered as complementary tools. PMID:25479849

Development and initial validation of the Classification of Early-Onset Scoliosis (C-EOS).

PubMed

Williams, Brendan A; Matsumoto, Hiroko; McCalla, Daren J; Akbarnia, Behrooz A; Blakemore, Laurel C; Betz, Randal R; Flynn, John M; Johnston, Charles E; McCarthy, Richard E; Roye, David P; Skaggs, David L; Smith, John T; Snyder, Brian D; Sponseller, Paul D; Sturm, Peter F; Thompson, George H; Yazici, Muharrem; Vitale, Michael G

2014-08-20

Early-onset scoliosis is a heterogeneous condition, with highly variable manifestations and natural history. No standardized classification system exists to describe and group patients, to guide optimal care, or to prognosticate outcomes within this population. A classification system for early-onset scoliosis is thus a necessary prerequisite to the timely evolution of care of these patients. Fifteen experienced surgeons participated in a nominal group technique designed to achieve a consensus-based classification system for early-onset scoliosis. A comprehensive list of factors important in managing early-onset scoliosis was generated using a standardized literature review, semi-structured interviews, and open forum discussion. Three group meetings and two rounds of surveying guided the selection of classification components, subgroupings, and cut-points. Initial validation of the system was conducted using an interobserver reliability assessment based on the classification of a series of thirty cases. Nominal group technique was used to identify three core variables (major curve angle, etiology, and kyphosis) with high group content validity scores. Age and curve progression ranked slightly lower. Participants evaluated the cases of thirty patients with early-onset scoliosis for reliability testing. The mean kappa value for etiology (0.64) was substantial, while the mean kappa values for major curve angle (0.95) and kyphosis (0.93) indicated almost perfect agreement. The final classification consisted of a continuous age prefix, etiology (congenital or structural, neuromuscular, syndromic, and idiopathic), major curve angle (1, 2, 3, or 4), and kyphosis (-, N, or +) variables, and an optional progression modifier (P0, P1, or P2). Utilizing formal consensus-building methods in a large group of surgeons experienced in treating early-onset scoliosis, a novel classification system for early-onset scoliosis was developed with all core components demonstrating substantial to excellent interobserver reliability. This classification system will serve as a foundation to guide ongoing research efforts and standardize communication in the clinical setting. Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.

Structural analysis of cylindrical thrust chambers, volume 1

NASA Technical Reports Server (NTRS)

Armstrong, W. H.

1979-01-01

Life predictions of regeneratively cooled rocket thrust chambers are normally derived from classical material fatigue principles. The failures observed in experimental thrust chambers do not appear to be due entirely to material fatigue. The chamber coolant walls in the failed areas exhibit progressive bulging and thinning during cyclic firings until the wall stress finally exceeds the material rupture stress and failure occurs. A preliminary analysis of an oxygen free high conductivity (OFHC) copper cylindrical thrust chamber demonstrated that the inclusion of cumulative cyclic plastic effects enables the observed coolant wall thinout to be predicted. The thinout curve constructed from the referent analysis of 10 firing cycles was extrapolated from the tenth cycle to the 200th cycle. The preliminary OFHC copper chamber 10-cycle analysis was extended so that the extrapolated thinout curve could be established by performing cyclic analysis of deformed configurations at 100 and 200 cycles. Thus the original range of extrapolation was reduced and the thinout curve was adjusted by using calculated thinout rates at 100 and 100 cycles. An analysis of the same underformed chamber model constructed of half-hard Amzirc to study the effect of material properties on the thinout curve is included.

Correlations between polyamine ratios and growth patterns in seedling roots

NASA Technical Reports Server (NTRS)

Shen, H. J.; Galston, A. W.

1985-01-01

The levels of putrescine, cadaverine, spermidine and spermine were determined in seedling roots of pea, tomato, millet and corn, as well as in corn coleoptiles and pea internodes. In all roots, putrescine content increased as elongation progressed, and the putrescine/spermine ratio closely paralleled the sigmoid growth curve up until the time of lateral root initiation. Spermidine and spermine were most abundant near the apices and declined progressively with increasing age of the cells. In the zone of differentiation of root hairs in pea roots, putrescine rose progressively with increasing age, while cadaverine declined. In both pea internodes and corn coleoptiles, the putrescine/spermidine ratio rises with increasing age and elongation. Thus, a block in the conversion of the diamine putrescine to the triamine spermidine may be an important step in the change from cell division to cell elongation.

The coupling technique: A two-wave acoustic method for the study of dislocation dynamics

NASA Astrophysics Data System (ADS)

Gremaud, G.; Bujard, M.; Benoit, W.

1987-03-01

Progress in the study of dislocation dynamics has been achieved using a two-wave acoustic method, which has been called the coupling technique. In this method, the attenuation α and the velocity v of ultrasonic waves are measured in a sample submitted simultaneously to a harmonic stress σ of low frequency. Closed curves Δα(σ) and Δv/v(σ) are drawn during each cycle of the applied stress. The shapes of these curves and their evolution are characteristic of each dislocation motion mechanism which is activated by the low-frequency applied stress. For this reason, the closed curves Δα(σ) and Δv/v(σ) can be considered as signatures of the interaction mechanism which controls the low-frequency dislocation motion. In this paper, the concept of signature is presented and explained with some experimental examples. It will also be shown that theoretical models can be developed which explain very well the experimental results.

Mechanism of oil bank formation, coalescence in porous media and emulsion and foam stability. Quarterly research progress report, July 1, 1984-September 30, 1984

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

Wasan, D.T.

The relative permeability model for two phase flow in porous media (Wasan 1983; Ramakrishnan and Wasan 1984) provides the necessary fractional flow curves at a given capillary number. These curves can be utilized in modeling both enhanced secondary and tertiary recovery processes. Important parameters in the fractional flow curves of our relative permeability model are the residual wetting and nonwetting phase saturations in a low capillary number flooding process. To understand, what constitutes the residual saturations, this quarter we have studied the displacement of one incompressible fluid by another in a porous medium using the network representation. The Bernoulli percolationmore » model for an infinite lattice graph is utilized in the interpretation of the capillary behavior of the medium, which ultimately determines residual saturations. The calculated capillary pressure-saturation relationship using Bethe lattice results agrees qualitatively with experimental data. 4 references, 2 figures.« less

A Serum Circulating miRNA Signature for Short-Term Risk of Progression to Active Tuberculosis Among Household Contacts.

PubMed

Duffy, Fergal J; Thompson, Ethan; Downing, Katrina; Suliman, Sara; Mayanja-Kizza, Harriet; Boom, W Henry; Thiel, Bonnie; Weiner Iii, January; Kaufmann, Stefan H E; Dover, Drew; Tabb, David L; Dockrell, Hazel M; Ottenhoff, Tom H M; Tromp, Gerard; Scriba, Thomas J; Zak, Daniel E; Walzl, Gerhard

2018-01-01

Biomarkers that predict who among recently Mycobacterium tuberculosis (MTB)-exposed individuals will progress to active tuberculosis are urgently needed. Intracellular microRNAs (miRNAs) regulate the host response to MTB and circulating miRNAs (c-miRNAs) have been developed as biomarkers for other diseases. We performed machine-learning analysis of c-miRNA measurements in the serum of adult household contacts (HHCs) of TB index cases from South Africa and Uganda and developed a c-miRNA-based signature of risk for progression to active TB. This c-miRNA-based signature significantly discriminated HHCs within 6 months of progression to active disease from HHCs that remained healthy in an independent test set [ROC area under the ROC curve (AUC) 0.74, progressors < 6 Mo to active TB and ROC AUC 0.66, up to 24 Mo to active TB], and complements the predictions of a previous cellular mRNA-based signature of TB risk.

The role of spinal concave–convex biases in the progression of idiopathic scoliosis

PubMed Central

Driscoll, Mark; Moreau, Alain; Villemure, Isabelle; Parent, Stefan

2009-01-01

Inadequate understanding of risk factors involved in the progression of idiopathic scoliosis restrains initial treatment to observation until the deformity shows signs of significant aggravation. The purpose of this analysis is to explore whether the concave–convex biases associated with scoliosis (local degeneration of the intervertebral discs, nucleus migration, and local increase in trabecular bone-mineral density of vertebral bodies) may be identified as progressive risk factors. Finite element models of a 26° right thoracic scoliotic spine were constructed based on experimental and clinical observations that included growth dynamics governed by mechanical stimulus. Stress distribution over the vertebral growth plates, progression of Cobb angles, and vertebral wedging were explored in models with and without the biases of concave–convex properties. The inclusion of the bias of concave–convex properties within the model both augmented the asymmetrical loading of the vertebral growth plates by up to 37% and further amplified the progression of Cobb angles and vertebral wedging by as much as 5.9° and 0.8°, respectively. Concave–convex biases are factors that influence the progression of scoliotic curves. Quantifying these parameters in a patient with scoliosis may further provide a better clinical assessment of the risk of progression. PMID:19130096

Bragg Curve, Biological Bragg Curve and Biological Issues in Space Radiation Protection with Shielding

NASA Technical Reports Server (NTRS)

Honglu, Wu; Cucinotta, F.A.; Durante, M.; Lin, Z.; Rusek, A.

2006-01-01

The space environment consists of a varying field of radiation particles including high-energy ions, with spacecraft shielding material providing the major protection to astronauts from harmful exposure. Unlike low-LET gamma or X-rays, the presence of shielding does not always reduce the radiation risks for energetic charged particle exposure. Since the dose delivered by the charged particle increases sharply as the particle approaches the end of its range, a position known as the Bragg peak, the Bragg curve does not necessarily represent the biological damage along the particle traversal since biological effects are influenced by the track structure of both primary and secondary particles. Therefore, the biological Bragg curve is dependent on the energy and the type of the primary particle, and may vary for different biological endpoints. To achieve a Bragg curve distribution, we exposed cells to energetic heavy ions with the beam geometry parallel to a monolayer of fibroblasts. Qualitative analyses of gamma-H2AX fluorescence, a known marker of DSBs, indicated increased clustering of DNA damage before the Bragg peak, enhanced homogenous distribution at the peak, and provided visual evidence of high linear energy transfer (LET) particle traversal of cells beyond the Bragg peak. A quantitative biological response curve generated for micronuclei (MN) induction across the Bragg curve did not reveal an increased yield of MN at the location of the Bragg peak. However, the ratio of mono-to bi-nucleated cells, which indicates inhibition in cell progression, increased at the Bragg peak location. These results, along with other biological concerns, show that space radiation protection with shielding can be a complicated issue.

Multiresolution and Explicit Methods for Vector Field Analysis and Visualization

NASA Technical Reports Server (NTRS)

1996-01-01

We first report on our current progress in the area of explicit methods for tangent curve computation. The basic idea of this method is to decompose the domain into a collection of triangles (or tetrahedra) and assume linear variation of the vector field over each cell. With this assumption, the equations which define a tangent curve become a system of linear, constant coefficient ODE's which can be solved explicitly. There are five different representation of the solution depending on the eigenvalues of the Jacobian. The analysis of these five cases is somewhat similar to the phase plane analysis often associate with critical point classification within the context of topological methods, but it is not exactly the same. There are some critical differences. Moving from one cell to the next as a tangent curve is tracked, requires the computation of the exit point which is an intersection of the solution of the constant coefficient ODE and the edge of a triangle. There are two possible approaches to this root computation problem. We can express the tangent curve into parametric form and substitute into an implicit form for the edge or we can express the edge in parametric form and substitute in an implicit form of the tangent curve. Normally the solution of a system of ODE's is given in parametric form and so the first approach is the most accessible and straightforward. The second approach requires the 'implicitization' of these parametric curves. The implicitization of parametric curves can often be rather difficult, but in this case we have been successful and have been able to develop algorithms and subsequent computer programs for both approaches. We will give these details along with some comparisons in a forthcoming research paper on this topic.

An Item Gains and Losses Analysis of False Memories Suggests Critical Items Receive More Item-Specific Processing than List Items

ERIC Educational Resources Information Center

Burns, Daniel J.; Martens, Nicholas J.; Bertoni, Alicia A.; Sweeney, Emily J.; Lividini, Michelle D.

2006-01-01

In a repeated testing paradigm, list items receiving item-specific processing are more likely to be recovered across successive tests (item gains), whereas items receiving relational processing are likely to be forgotten progressively less on successive tests. Moreover, analysis of cumulative-recall curves has shown that item-specific processing…

IQ Gains in Argentina between 1964 and 1998

ERIC Educational Resources Information Center

Flynn, James R.; Rossi-Case, Lilia

2012-01-01

The literature on IQ gains in Latin America is sparse. We estimate gains on Raven's Progressive Matrices in the city of La Plata (Argentina) between 1964 and 1998. The gains are robust at the top of the curve as well as at the bottom. Therefore, they are contrary to the hypothesis that nutrition played a major role in recent Argentine IQ gains.…

Latino Adolescents' Ethnic Identity: Is There a Developmental Progression and Does Growth in Ethnic Identity Predict Growth in Self-Esteem?

ERIC Educational Resources Information Center

Umana-Taylor, Adriana J.; Gonzales-Backen, Melinda A.; Guimond, Amy B.

2009-01-01

The current longitudinal study of 323 Latino adolescents (50.5% male; M age = 15.31 years) examined whether ethnic identity exploration, resolution, and affirmation demonstrated significant growth over a 4-year period and whether growth in ethnic identity predicted growth in self-esteem. Findings from multiple-group latent growth curve models…

Induction of Micronuclei in Human Fibroblasts across the Bragg Curve of Energetic Si and Fe Ions

NASA Technical Reports Server (NTRS)

Wu, H.; Rusek, A.; Hada, M.

2006-01-01

The space environment consists of a varying field of radiation particles including high-energy ions, with spacecraft shielding material providing the major protection to astronauts from harmful exposure. Unlike low-LET gamma or X-rays, the presence of shielding does not always reduce the radiation risks for energetic charged particle exposure. Since the dose delivered by the charged particle increases sharply as the particle approaches the end of its range, a position known as the Bragg peak, the Bragg curve does not necessarily represent the biological damage along the particle traversal since biological effects are influenced by the track structure of both primary and secondary particles. Therefore, the biological Bragg curve is dependent on the energy and the type of the primary particle, and may vary for different biological endpoints. We studied micronuclei (MN) induction across the Bragg curve of Si and Fe ions at incident energies of 300 MeV/nucleon and 1 GeV/nucleon. A quantitative biological response curve did not reveal an increased yield of MN at the location of the Bragg peak. However, the ratio of mono- to bi-nucleated cells, which indicates inhibition in cell progression, increased at the Bragg peak location. These results confirm the hypothesis that severely damaged cells at the Bragg peak are likely to go through reproduction death.

Framingham risk score can predict cognitive decline progression in Alzheimer's disease.

PubMed

Viticchi, Giovanna; Falsetti, Lorenzo; Buratti, Laura; Boria, Cristiano; Luzzi, Simona; Bartolini, Marco; Provinciali, Leandro; Silvestrini, Mauro

2015-11-01

The role of vascular factors in influencing cognitive decline has been extensively investigated, and some difficulties in defining their weight in dementia pathogenesis have emerged. The aim of the study was to investigate the relevance of the Framingham cardiovascular risk profile (FCRP) in influencing cognitive deterioration in a population of Alzheimer's disease (AD) patients. Two hundred eighty-four consecutive AD patients were enrolled. For each patient, FCRP score was calculated. We did a 1-year follow-up to quantify the cognitive decline by recording changes in the Clinical Dementia Rating score. The FCRP score predicted cognitive deterioration with an area under the curve of 0.63 (95% confidence interval: 0.57-0.69; p < 0.0001). In the subpopulation of patients with a genetic increased predisposition to develop cognitive deterioration and with an advanced vascular impairment, the FCRP predictive value significantly increased with an area under the curve of 0.77 (95% confidence interval: 0.52-0.93; p < 0.05). Our findings show that FCRP can predict the progression of deterioration in AD patients. This was particularly evident in patients with major genetic and atherosclerotic risk factors. Copyright © 2015 Elsevier Inc. All rights reserved.

Rapid learning curve assessment in an ex vivo training system for microincisional glaucoma surgery.

PubMed

Dang, Yalong; Waxman, Susannah; Wang, Chao; Parikh, Hardik A; Bussel, Igor I; Loewen, Ralitsa T; Xia, Xiaobo; Lathrop, Kira L; Bilonick, Richard A; Loewen, Nils A

2017-05-09

Increasing prevalence and cost of glaucoma have increased the demand for surgeons well trained in newer, microincisional surgery. These procedures occur in a highly confined space, making them difficult to learn by observation or assistance alone as is currently done. We hypothesized that our ex vivo outflow model is sensitive enough to allow computing individual learning curves to quantify progress and refine techniques. Seven trainees performed nine trabectome-mediated ab interno trabeculectomies in pig eyes (n = 63). An expert surgeon rated the procedure using an Operating Room Score (ORS). The extent of outflow beds accessed was measured with canalograms. Data was fitted using mixed effect models. ORS reached a half-maximum on an asymptote after only 2.5 eyes. Surgical time decreased by 1.4 minutes per eye in a linear fashion. The ablation arc followed an asymptotic function with a half-maximum inflection point after 5.3 eyes. Canalograms revealed that this progress did not correlate well with improvement in outflow, suggesting instead that about 30 eyes are needed for true mastery. This inexpensive pig eye model provides a safe and effective microsurgical training model and allows objective quantification of outcomes for the first time.

Atom Resonance Lines for Modeling Atmosphere: Studies of Pressure-Broadening of Alkali Atom Resonance Lines for Modeling Atmospheres of Extrasolar Giant Planets and Brown Dwarfs

NASA Technical Reports Server (NTRS)

Hasan, Hashima (Technical Monitor); Kirby, K.; Babb, J.; Yoshino, K.

2005-01-01

We report on progress made in a joint program of theoretical and experimental research to study the line-broadening of alkali atom resonance lines due to collisions with species such as helium and molecular hydrogen. Accurate knowledge of the line profiles of Na and K as a function of temperature and pressure will allow such lines to serve as valuable diagnostics of the atmospheres of brown dwarfs and extra-solar giant planets. A new experimental apparatus has been designed, built and tested over the past year, and we are poised to begin collecting data on the first system of interest, the potassium resonance lines perturbed by collisions with helium. On the theoretical front, calculations of line-broadening due to sodium collisions with helium are nearly complete, using accurate molecular potential energy curves and transition moments just recently computed for this system. In addition we have completed calculations of the three relevant potential energy curves and associated transition moments for K - He, using the MOLPRO quantum chemistry codes. Currently, calculations of the potential surfaces describing K-H2 are in progress.

Kinetics of suicide substrates. Practical procedures for determining parameters.

PubMed Central

Waley, S G

1985-01-01

Many clinically important or mechanistically interesting inhibitors react with enzymes by a branched pathway in which inactivation of the enzyme and formation of product are competing reactions. The steady-state kinetics for this pathway [Waley (1980) Biochem. J. 185, 771-773] gave equations for progress curves that were cumbersome. A convenient linear plot is now described. The time (t1/2) for 50% inactivation of the enzyme (this is also the time for 50% formation of product), or for 50% loss of substrate, is measured in a series of experiments in which the concentration of inhibitor, [I]0, is varied; in these experiments the ratio of the concentration of enzyme to the concentration of inhibitor is kept fixed. Then a plot of [I]0 X t1/2 against [I]0 is linear, and the kinetic parameters can be found from the slope and intercept. Furthermore, simplifications of the equations for progress curves are described that are valid when the concentration of inhibitors is high, or is low, or when the extent of reaction is low. The use of simulated data has shown that the recommended methods are not unduly sensitive to experimental error. PMID:4004802

Kinetic analysis of enzyme systems with suicide substrate in the presence of a reversible competitive inhibitor, tested by simulated progress curves.

PubMed

Moruno-Dávila, M A; Garrido-del Solo, C; García-Moreno, M; Havsteen, B H; Garcia-Sevilla, F; Garcia-Cánovas, F; Varón, R

2001-02-01

The use of suicide substrates remains a very important and useful method in enzymology for studying enzyme mechanisms and designing potential drugs. Suicide substrates act as modified substrates for the target enzymes and bind to the active site. Therefore the presence of a competitive reversible inhibitor decreases the rate of substrate-induced inactivation and protects the enzyme from this inactivation. This lowering on the inactivation rate has evident physiological advantages, since it allows the easy acquisition of experimental data and facilitates kinetic data analysis by providing another variable (inhibitor concentration). However despite the importance of the simultaneous action of a suicide substrate and a competitive reversible inhibition, to date no corresponding kinetic analysis has been carried out. Therefore we present a general kinetic analysis of a Michaelis-Menten reaction mechanism with double inhibition caused by both, a suicide substrate and a competitive reversible inhibitor. We assume rapid equilibrium of the reversible reaction steps involved, while the time course equations for the reaction product have been derived with the assumption of a limiting enzyme. The goodness of the analytical solutions has been tested by comparison with the simulated curves obtained by numerical integration. A kinetic data analysis to determine the corresponding kinetic parameters from the time progress curve of the product is suggested. In conclusion, we present a complete kinetic analysis of an enzyme reaction mechanism as described above in an attempt to fill a gap in the theoretical treatment of this type of system.

Monitoring progress in population health: trends in premature death rates.

PubMed

Remington, Patrick L; Catlin, Bridget B; Kindig, David A

2013-12-26

Trends in population health outcomes can be monitored to evaluate the performance of population health systems at the national, state, and local levels. The objective of this study was to compare and contrast 4 measures for assessing progress in population health improvement by using age-adjusted premature death rates as a summary measure of the overall health outcomes in the United States and in all 50 states. To evaluate the performance of statewide population health systems during the past 20 years, we used 4 measures of age-adjusted premature (<75 years of age) death rates: current rates (2009), baseline trends (1990s), follow-up trends (2000s), and changes in trends from baseline to the follow-up periods (ie, "bending the curve"). Current premature death rates varied by approximately twofold, with the lowest rate in Minnesota (268 deaths per 100,000) and the highest rate in Mississippi (482 deaths per 100,000). Rates improved the most in New York during the baseline period (-3.05% per year) and in New Jersey during the follow-up period (-2.87% per year), whereas Oklahoma ranked last in trends during both periods (-0.30%/y, baseline; +0.18%/y, follow-up). Trends improved the most in Connecticut, bending the curve downward by -1.03%; trends worsened the most in New Mexico, bending the curve upward by 1.21%. Current premature death rates, recent trends, and changes in trends vary by state in the United States. Policy makers can use these measures to evaluate the long-term population health impact of broad health care, behavioral, social, and economic investments in population health.

Semiempirical studies of atomic structure. Progress report, 1 July 1991--1 October 1993

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

Curtis, L.J.

1993-10-01

Atomic structure/properties of highly ionized many-electron systems are studied using sensitive semiempirical data systematization, experiment, and theory. Measurements are made using fast ion beams, combined with data from laser- and tokamak-produced plasmas, astrophysical sources, and light sources. Results during this 3-y period are discussed under the following headings: Invited review article (decay rates in systems of negative ions to very heavy one-electron ions), fast ion beam lifetime measurements (Pt sequence, neutral carbon, Na sequence), multiplexed decay curve measurements, multiplexed decay curve measurements (lifetimes of alkali-like resonance transitions, spin-forbidden intercombination lines), lifetimes in Ne sequence, lifetimes for H and He sequences,more » data-based semiempirical formulations, calculations, and accelerator studies.« less

The shape of the glucose concentration curve during an oral glucose tolerance test predicts risk for type 1 diabetes.

PubMed

Ismail, Heba M; Xu, Ping; Libman, Ingrid M; Becker, Dorothy J; Marks, Jennifer B; Skyler, Jay S; Palmer, Jerry P; Sosenko, Jay M

2018-01-01

We aimed to examine: (1) whether specific glucose-response curve shapes during OGTTs are predictive of type 1 diabetes development; and (2) the extent to which the glucose-response curve is influenced by insulin secretion. Autoantibody-positive relatives of people with type 1 diabetes whose baseline OGTT met the definition of a monophasic or biphasic glucose-response curve were followed for the development of type 1 diabetes (n = 2627). A monophasic curve was defined as an increase in OGTT glucose between 30 and 90 min followed by a decline of ≥ 0.25 mmol/l between 90 and 120 min. A biphasic response curve was defined as a decrease in glucose after an initial increase, followed by a second increase of ≥ 0.25 mmol/l. Associations of type 1 diabetes risk with glucose curve shapes were examined using cumulative incidence curve comparisons and proportional hazards regression. C-peptide responses were compared with and without adjustments for potential confounders. The majority of participants had a monophasic curve at baseline (n = 1732 [66%] vs n = 895 [34%]). The biphasic group had a lower cumulative incidence of type 1 diabetes (p < 0.001), which persisted after adjustments for age, sex, BMI z score and number of autoantibodies (p < 0.001). Among the monophasic group, the risk of type 1 diabetes was greater for those with a glucose peak at 90 min than for those with a peak at 30 min; the difference persisted after adjustments (p < 0.001). Compared with the biphasic group, the monophasic group had a lower early C-peptide (30-0 min) response, a lower C-peptide index (30-0 min C-peptide/30-0 min glucose), as well as a greater 2 h C-peptide level (p < 0.001 for all). Those with biphasic glucose curves have a lower risk of progression to type 1 diabetes than those with monophasic curves, and the risk among the monophasic group is increased when the glucose peak occurs at 90 min than at 30 min. Differences in glucose curve shapes between the monophasic and biphasic groups appear to be related to C-peptide responses.

Pseudo progression identification of glioblastoma with dictionary learning.

PubMed

Zhang, Jian; Yu, Hengyong; Qian, Xiaohua; Liu, Keqin; Tan, Hua; Yang, Tielin; Wang, Maode; Li, King Chuen; Chan, Michael D; Debinski, Waldemar; Paulsson, Anna; Wang, Ge; Zhou, Xiaobo

2016-06-01

Although the use of temozolomide in chemoradiotherapy is effective, the challenging clinical problem of pseudo progression has been raised in brain tumor treatment. This study aims to distinguish pseudo progression from true progression. Between 2000 and 2012, a total of 161 patients with glioblastoma multiforme (GBM) were treated with chemoradiotherapy at our hospital. Among the patients, 79 had their diffusion tensor imaging (DTI) data acquired at the earliest diagnosed date of pseudo progression or true progression, and 23 had both DTI data and genomic data. Clinical records of all patients were kept in good condition. Volumetric fractional anisotropy (FA) images obtained from the DTI data were decomposed into a sequence of sparse representations. Then, a feature selection algorithm was applied to extract the critical features from the feature matrix to reduce the size of the feature matrix and to improve the classification accuracy. The proposed approach was validated using the 79 samples with clinical DTI data. Satisfactory results were obtained under different experimental conditions. The area under the receiver operating characteristic (ROC) curve (AUC) was 0.87 for a given dictionary with 1024 atoms. For the subgroup of 23 samples, genomics data analysis was also performed. Results implied further perspective on pseudo progression classification. The proposed method can determine pseudo progression and true progression with improved accuracy. Laboring segmentation is no longer necessary because this skillfully designed method is not sensitive to tumor location. Copyright © 2016 Elsevier Ltd. All rights reserved.

Exact and Approximate Solutions for the Decades-Old Michaelis-Menten Equation: Progress-Curve Analysis through Integrated Rate Equations

ERIC Educational Resources Information Center

Golicnik, Marko

2011-01-01

The Michaelis-Menten rate equation can be found in most general biochemistry textbooks, where the time derivative of the substrate is a hyperbolic function of two kinetic parameters (the limiting rate "V", and the Michaelis constant "K"[subscript M]) and the amount of substrate. However, fundamental concepts of enzyme kinetics can be difficult to…

Removing the tree-ring width biological trend using expected basal area increment

Treesearch

Franco Biondi; Fares Qeadan

2008-01-01

One of the main elements of dendrochronological standardization is the removal of the biological trend, i.e., the progressive decline of ring width along a cross-sectional radius that is mostly caused by the corresponding increase in stem diameter over time. A very common option for removing this biological trend is to fit a modified negative exponential curve to the...

Progress Toward Adaptive Integration and Optimization of Automated and Neural Processing Systems: Establishing Neural and Behavioral Benchmarks of Optimized Performance

DTIC Science & Technology

2014-11-01

Paradigm ............................................................................19 3.4 Collaborative BCI for Improving Overall Performance...interfaces ( BCIs ) provide the biggest improvement in performance? Can we demonstrate clear advantages with BCIs ? 2 2. Simulator Development and...stimuli in real time. Fig. 18 ROC curves for each subject after the combination of 2 trials 3.4 Collaborative BCI for Improving Overall

Use of Latent Growth Curve Modeling for Assessing the Effects of Summer and After-School Learning on Adolescent Students' Achievement Gap

ERIC Educational Resources Information Center

Lin, Chunn-Ying; Hsieh, Ya-Heng; Chen, Cheng-Hung

2015-01-01

Many Western researchers have found that the gaps in the learning progress between students from different socioeconomic statuses primarily occur due to the accumulated effects of long summer vacations, rather than during the school years. However, it remains to be seen whether these findings can be cross-culturally applied to children in Taiwan.…

Longitudinal Analysis of the Role of Perceived Self-Efficacy for Self-Regulated Learning in Academic Continuance and Achievement

ERIC Educational Resources Information Center

Caprara, Gian Vittorio; Fida, Roberta; Vecchione, Michele; Del Bove, Giannetta; Vecchio, Giovanni Maria; Barbaranelli, Claudio; Bandura, Albert

2008-01-01

The present study examined the developmental course of perceived efficacy for self-regulated learning and its contribution to academic achievement and likelihood of remaining in school in a sample of 412 Italian students (48% males and 52% females ranging in age from 12 to 22 years). Latent growth curve analysis revealed a progressive decline in…

Progression of spinal deformity in wheelchair-dependent patients with Duchenne muscular dystrophy who are not treated with steroids: coronal plane (scoliosis) and sagittal plane (kyphosis, lordosis) deformity.

PubMed

Shapiro, F; Zurakowski, D; Bui, T; Darras, B T

2014-01-01

We determined the frequency, rate and extent of development of scoliosis (coronal plane deformity) in wheelchair-dependent patients with Duchenne muscular dystrophy (DMD) who were not receiving steroid treatment. We also assessed kyphosis and lordosis (sagittal plane deformity). The extent of scoliosis was assessed on sitting anteroposterior (AP) spinal radiographs in 88 consecutive non-ambulatory patients with DMD. Radiographs were studied from the time the patients became wheelchair-dependent until the time of spinal fusion, or the latest assessment if surgery was not undertaken. Progression was estimated using a longitudinal mixed-model regression analysis to handle repeated measurements. Scoliosis ≥ 10° occurred in 85 of 88 patients (97%), ≥ 20° in 78 of 88 (89%) and ≥ 30° in 66 of 88 patients (75%). The fitted longitudinal model revealed that time in a wheelchair was a highly significant predictor of the magnitude of the curve, independent of the age of the patient (p < 0.001). Scoliosis developed in virtually all DMD patients not receiving steroids once they became wheelchair-dependent, and the degree of deformity deteriorated over time. In general, scoliosis increased at a constant rate, beginning at the time of wheelchair-dependency (p < 0.001). In some there was no scoliosis for as long as three years after dependency, but scoliosis then developed and increased at a constant rate. Some patients showed a rapid increase in the rate of progression of the curve after a few years - the clinical phenomenon of a rapidly collapsing curve over a few months. A sagittal plane kyphotic deformity was seen in 37 of 60 patients (62%) with appropriate radiographs, with 23 (38%) showing lumbar lordosis (16 (27%) abnormal and seven (11%) normal). This study provides a baseline to assess the effects of steroids and other forms of treatment on the natural history of scoliosis in patients with DMD, and an approach to assessing spinal deformity in the coronal and sagittal planes in wheelchair-dependent patients with other neuromuscular disorders.

Nano-Bio-Mechanics of Neuroblastoma Cells Using AFM

NASA Astrophysics Data System (ADS)

Bastatas, Lyndon; Matthews, James; Kang, Min; Park, Soyeun

2011-10-01

We have conducted an in vitro study to determine the elastic moduli of neurobalstoma cell lines using atomic force microscopy. Using a panel of cell lines established from neuroblastoma patients at different stages of disease progress and treatment, we have investigated the differences in elastic moduli during a course of cancer progression and chemotherapy. The cells were grown on the hard substrates that are chemically functionalized to enhance adhesion. We have performed the AFM indentation experiments with different applied forces from the AFM probe. For the purpose of the comparison between cell lines, the indentations were performed only on cell centers. The obtained force-distance curves were analyzed using the Hertz model in order to extract the elastic moduli. We have found that the elastic moduli of human neuroblastoma cells significantly varied during the disease progression. We postulate that the observed difference might be affected by the treatment and chemotherapy.

Universality of accelerating change

NASA Astrophysics Data System (ADS)

Eliazar, Iddo; Shlesinger, Michael F.

2018-03-01

On large time scales the progress of human technology follows an exponential growth trend that is termed accelerating change. The exponential growth trend is commonly considered to be the amalgamated effect of consecutive technology revolutions - where the progress carried in by each technology revolution follows an S-curve, and where the aging of each technology revolution drives humanity to push for the next technology revolution. Thus, as a collective, mankind is the 'intelligent designer' of accelerating change. In this paper we establish that the exponential growth trend - and only this trend - emerges universally, on large time scales, from systems that combine together two elements: randomness and amalgamation. Hence, the universal generation of accelerating change can be attained by systems with no 'intelligent designer'.

Mapping morphological shape as a high-dimensional functional curve

PubMed Central

Fu, Guifang; Huang, Mian; Bo, Wenhao; Hao, Han; Wu, Rongling

2018-01-01

Abstract Detecting how genes regulate biological shape has become a multidisciplinary research interest because of its wide application in many disciplines. Despite its fundamental importance, the challenges of accurately extracting information from an image, statistically modeling the high-dimensional shape and meticulously locating shape quantitative trait loci (QTL) affect the progress of this research. In this article, we propose a novel integrated framework that incorporates shape analysis, statistical curve modeling and genetic mapping to detect significant QTLs regulating variation of biological shape traits. After quantifying morphological shape via a radius centroid contour approach, each shape, as a phenotype, was characterized as a high-dimensional curve, varying as angle θ runs clockwise with the first point starting from angle zero. We then modeled the dynamic trajectories of three mean curves and variation patterns as functions of θ. Our framework led to the detection of a few significant QTLs regulating the variation of leaf shape collected from a natural population of poplar, Populus szechuanica var tibetica. This population, distributed at altitudes 2000–4500 m above sea level, is an evolutionarily important plant species. This is the first work in the quantitative genetic shape mapping area that emphasizes a sense of ‘function’ instead of decomposing the shape into a few discrete principal components, as the majority of shape studies do. PMID:28062411

Evaluation of a Stochastic Inactivation Model for Heat-Activated Spores of Bacillus spp. ▿

PubMed Central

Corradini, Maria G.; Normand, Mark D.; Eisenberg, Murray; Peleg, Micha

2010-01-01

Heat activates the dormant spores of certain Bacillus spp., which is reflected in the “activation shoulder” in their survival curves. At the same time, heat also inactivates the already active and just activated spores, as well as those still dormant. A stochastic model based on progressively changing probabilities of activation and inactivation can describe this phenomenon. The model is presented in a fully probabilistic discrete form for individual and small groups of spores and as a semicontinuous deterministic model for large spore populations. The same underlying algorithm applies to both isothermal and dynamic heat treatments. Its construction does not require the assumption of the activation and inactivation kinetics or knowledge of their biophysical and biochemical mechanisms. A simplified version of the semicontinuous model was used to simulate survival curves with the activation shoulder that are reminiscent of experimental curves reported in the literature. The model is not intended to replace current models to predict dynamic inactivation but only to offer a conceptual alternative to their interpretation. Nevertheless, by linking the survival curve's shape to probabilities of events at the individual spore level, the model explains, and can be used to simulate, the irregular activation and survival patterns of individual and small groups of spores, which might be involved in food poisoning and spoilage. PMID:20453137

Curved Walking Rehabilitation with a Rotating Treadmill in Patients with Parkinson’s Disease: A Proof of Concept

PubMed Central

Godi, Marco; Giardini, Marica; Nardone, Antonio; Turcato, Anna Maria; Caligari, Marco; Pisano, Fabrizio; Schieppati, Marco

2017-01-01

Training subjects to step-in-place eyes open on a rotating platform while maintaining a fixed body orientation in space [podokinetic stimulation (PKS)] produces a posteffect consisting in inadvertent turning around while stepping-in-place eyes closed [podokinetic after-rotation (PKAR)]. Since the rationale for rehabilitation of curved walking in Parkinson’s disease is not fully known, we tested the hypothesis that repeated PKS favors the production of curved walking in these patients, who are uneasy with turning, even when straight walking is little affected. Fifteen patients participated in 10 training sessions distributed in 3 weeks. Both counterclockwise and clockwise PKS were randomly administered in each session. PKS velocity and duration were gradually increased over sessions. The velocity and duration of the following PKAR were assessed. All patients showed PKAR, which increased progressively in peak velocity and duration. In addition, before and at the end of the treatment, all patients walked overground along linear and circular trajectories. Post-training, the velocity of walking bouts increased, more so for the circular than the linear trajectory. Cadence was not affected. This study has shown that parkinsonian patients learn to produce turning while stepping when faced with appropriate training and that this capacity translates into improved overground curved walking. PMID:28293213

Curved Walking Rehabilitation with a Rotating Treadmill in Patients with Parkinson's Disease: A Proof of Concept.

PubMed

Godi, Marco; Giardini, Marica; Nardone, Antonio; Turcato, Anna Maria; Caligari, Marco; Pisano, Fabrizio; Schieppati, Marco

2017-01-01

Training subjects to step-in-place eyes open on a rotating platform while maintaining a fixed body orientation in space [podokinetic stimulation (PKS)] produces a posteffect consisting in inadvertent turning around while stepping-in-place eyes closed [podokinetic after-rotation (PKAR)]. Since the rationale for rehabilitation of curved walking in Parkinson's disease is not fully known, we tested the hypothesis that repeated PKS favors the production of curved walking in these patients, who are uneasy with turning, even when straight walking is little affected. Fifteen patients participated in 10 training sessions distributed in 3 weeks. Both counterclockwise and clockwise PKS were randomly administered in each session. PKS velocity and duration were gradually increased over sessions. The velocity and duration of the following PKAR were assessed. All patients showed PKAR, which increased progressively in peak velocity and duration. In addition, before and at the end of the treatment, all patients walked overground along linear and circular trajectories. Post-training, the velocity of walking bouts increased, more so for the circular than the linear trajectory. Cadence was not affected. This study has shown that parkinsonian patients learn to produce turning while stepping when faced with appropriate training and that this capacity translates into improved overground curved walking.

Robust prediction of three-dimensional spinal curve from back surface for non-invasive follow-up of scoliosis

NASA Astrophysics Data System (ADS)

Bergeron, Charles; Labelle, Hubert; Ronsky, Janet; Zernicke, Ronald

2005-04-01

Spinal curvature progression in scoliosis patients is monitored from X-rays, and this serial exposure to harmful radiation increases the incidence of developing cancer. With the aim of reducing the invasiveness of follow-up, this study seeks to relate the three-dimensional external surface to the internal geometry, having assumed that that the physiological links between these are sufficiently regular across patients. A database was used of 194 quasi-simultaneous acquisitions of two X-rays and a 3D laser scan of the entire trunk. Data was processed to sets of datapoints representing the trunk surface and spinal curve. Functional data analyses were performed using generalized Fourier series using a Haar basis and functional minimum noise fractions. The resulting coefficients became inputs and outputs, respectively, to an array of support vector regression (SVR) machines. SVR parameters were set based on theoretical results, and cross-validation increased confidence in the system's performance. Predicted lateral and frontal views of the spinal curve from the back surface demonstrated average L2-errors of 6.13 and 4.38 millimetres, respectively, across the test set; these compared favourably with measurement error in data. This constitutes a first robust prediction of the 3D spinal curve from external data using learning techniques.

Monitoring cotton root rot by synthetic Sentinel-2 NDVI time series using improved spatial and temporal data fusion.

PubMed

Wu, Mingquan; Yang, Chenghai; Song, Xiaoyu; Hoffmann, Wesley Clint; Huang, Wenjiang; Niu, Zheng; Wang, Changyao; Li, Wang; Yu, Bo

2018-01-31

To better understand the progression of cotton root rot within the season, time series monitoring is required. In this study, an improved spatial and temporal data fusion approach (ISTDFA) was employed to combine 250-m Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Different Vegetation Index (NDVI) and 10-m Sentinetl-2 NDVI data to generate a synthetic Sentinel-2 NDVI time series for monitoring this disease. Then, the phenology of healthy cotton and infected cotton was modeled using a logistic model. Finally, several phenology parameters, including the onset day of greenness minimum (OGM), growing season length (GLS), onset of greenness increase (OGI), max NDVI value, and integral area of the phenology curve, were calculated. The results showed that ISTDFA could be used to combine time series MODIS and Sentinel-2 NDVI data with a correlation coefficient of 0.893. The logistic model could describe the phenology curves with R-squared values from 0.791 to 0.969. Moreover, the phenology curve of infected cotton showed a significant difference from that of healthy cotton. The max NDVI value, OGM, GSL and the integral area of the phenology curve for infected cotton were reduced by 0.045, 30 days, 22 days, and 18.54%, respectively, compared with those for healthy cotton.

Baseline genetic associations in the Parkinson's Progression Markers Initiative (PPMI).

PubMed

Nalls, Mike A; Keller, Margaux F; Hernandez, Dena G; Chen, Lan; Stone, David J; Singleton, Andrew B

2016-01-01

The Parkinson's Progression Marker Initiative is an international multicenter study whose main goal is investigating markers for Parkinson's disease (PD) progression as part of a path to a treatment for the disease. This manuscript describes the baseline genetic architecture of this study, providing not only a catalog of disease-linked variants and mutations, but also quantitative measures with which to adjust for population structure. Three hundred eighty-three newly diagnosed typical PD cases, 65 atypical PD and 178 healthy controls, from the Parkinson's Progression Marker Initiative study have been genotyped on the NeuroX or Immunochip arrays. These data are freely available to all researchers interested in pursuing PD research within the Parkinson's Progression Marker Initiative. The Parkinson's Progression Marker Initiative represents a study population with low genetic heterogeneity. We recapitulate known PD associations from large-scale genome-wide association studies and refine genetic risk score models for PD predictability (area under the curve, ∼0.74). We show the presence of six LRRK2 p.G2019S and nine GBA p.N370S mutation carriers. The Parkinson's Progression Marker Initiative study and its genetic data are useful in studies of PD biomarkers. The genetic architecture described here will be useful in the analysis of myriad biological and clinical traits within this study. © 2015 International Parkinson and Movement Disorder Society.

Deep Magnetic Diagenesis in Sediments: Progressive and Punctuated Processes.

NASA Astrophysics Data System (ADS)

Musgrave, R. J.; Kars, M. A. C.; Vega, M. E.

2017-12-01

Magnetic diagenesis in the tuffaceous muds, mudstones and volcaniclastic rocks cored at IODP Site U1437 is a product of progressive processes that continue throughout the 1800-m-thick sequence, punctuated by superimposed features corresponding to a series of influxes of fluids and concentrations of hydrocarbons. XRD, visual examination and SEM images indicate the presence of both magnetite and the magnetic sulfide greigite. Inferences from high values of saturation isothermal remanence normalised by magnetic susceptibility (SIRM/χ), distribution of hysteresis data near a diagenetic greigite curve on a Day plot, and 'humping' of low-temperature cycles of SIRM suggest that detrital magnetite and diagenetic greigite are both significant contributors to the magnetic assemblage, with greigite constituting a higher proportion in shallower samples. Progressive magnetic diagenesis is expressed as a continuing background decrease in SIRM/χ. FORC curves indicate an initial diagenetic growth of one or more higher-coercivity phases, followed downhole by increasing loss of all but low-coercivity material. The downhole pattern is consistent with progressive loss of fine-grained magnetite, initial authigenesis of greigite, and progressive pyritisation of the greigite. Some coarse-grained samples from the base of the sequence buck the trend, exhibiting SD behavior probably related to surviving magnetite inclusions in silicates. Shipboard fluid analysis revealed a complex profile of interstitial-water geochemistry, marked by several fluid influxes, including inputs of sulfate-rich water at about 275 and 460 meters below seafloor (mbsf). Methane concentrations, mostly low, markedly increase in the interval between 750 and 1460 mbsf, and ethane appears below an inferred fault at 1104 mbsf. Each of these fluid events is marked by offsets in the rock magnetic parameters SIRM/χ, S-0.3T, and DJH, representing repeated phases of late diagenetic growth of greigite in response to supplies of sulfate, intervals of enhanced pyritisation of greigite where concentrations of deeply sourced methane may be accompanied by H2S, and a more enigmatic response to the thermogenic ethane interval which seems to both dissolve any remaining fine-grained magnetite and grow a new generation of greigite.

Birth weight centiles by gestational age for twins born in south India.

PubMed

Premkumar, Prasanna; Antonisamy, Belavendra; Mathews, Jiji; Benjamin, Santhosh; Regi, Annie; Jose, Ruby; Kuruvilla, Anil; Mathai, Mathews

2016-03-24

Birth weight centile curves are commonly used as a screening tool and to assess the position of a newborn on a given reference distribution. Birth weight of twins are known to be less than those of comparable singletons and twin-specific birth weight centile curves are recommended for use. In this study, we aim to construct gestational age specific birth weight centile curves for twins born in south India. The study was conducted at the Christian Medical College, Vellore, south India. The birth records of all consecutive pregnancies resulting in twin births between 1991 and 2005 were reviewed. Only live twin births between 24 and 42 weeks of gestation were included. Birth weight centiles for gestational age were obtained using the methodology of generalized additive models for location, scale and shape (GAMLSS). Centiles curves were obtained separately for monochorionic and dichorionic twins. Of 1530 twin pregnancies delivered during the study period (1991-2005), 1304 were included in the analysis. The median gestational age at birth was 36 weeks (1st quartile 34, 3rd quartile 38 weeks). Smoothed percentile curves for birth weight by gestational age increased progressively till 38 weeks and levels off thereafter. Compared with dichorionic twins, monochorionic twins had lower birth weight for gestational age from after 27 weeks. We provide centile values of birth weight at 24 to 42 completed weeks of gestation for twins born in south India. These charts could be used both in routine clinical assessments and epidemiological studies.

Effects of amlodipine and adenosine on coronary haemodynamics: in vivo study and numerical simulation.

PubMed

De Lazzari, Claudio; L'Abbate, Antonio; Micalizzi, Mauro; Trivella, Maria Giovanna; Neglia, Danilo

2014-11-01

Amlodipine (AMLO) is a calcium channel blocker with vasodilating properties, in which the specific effects on the coronary circulation are not fully known. Coronary flow velocity-pressure (F/P) curves were obtained at rest and during administration of AMLO (10 mg to 20 mg iv) or adenosine (ADO, 1 mg ic) in 10 normal subjects (six women, age 48 ± 14 years). F/P curves were reproduced in a numerical simulator of systemic and coronary circulations (CARDIOSIM(©)) by adjustment of coronary resistance ( > or < 100 μm diameter vessels) and extravascular resistance applied to smaller vessels at endocardial (ENDO), middle and epicardial (EPI) myocardial layers. Best matching of in silico to in vivo curves was achieved by trial and error approach. ADO induced 170% and 250% increase in coronary flow velocity CFV and F/P diastolic slope as compared to 80% and 25-30% increase induced by AMLO, respectively. In the cardiovascular model, AMLO effects were predicted by progressive reduction of>100 μm vessels resistance from EPI to ENDO. ADO effects were mimicked by reducing resistance of both>100 μm and < 100 μm vessels, progressively from EPI to ENDO in the latter. Additional reduction in extravascular resistance avoided to impose a transmural gradient of vasodilating effect for both drugs. Numerical simulation predicts vasodilating effects of AMLO mainly on larger arteries and of ADO on both>and < 100 μm vessels. In vivo F/P loops could be completely reproduced in silico by adding extravascular resistance reduction for both drugs. Numerical simulator is useful tool for exploring the coronary effects of cardioactive drugs.

Chemical and magnetic properties of rapidly cooled metastable ferri-ilmenite solid solutions - IV: the fine structure of self-reversed thermoremanent magnetization

NASA Astrophysics Data System (ADS)

Robinson, Peter; McEnroe, S. A.; Fabian, K.; Harrison, R. J.; Thomas, C. I.; Mukai, H.

2014-03-01

Magnetic experiments, a Monte Carlo simulation and transmission electron microscopy observations combine to confirm variable chemical phase separation during quench and annealing of metastable ferri-ilmenite compositions, caused by inhomogeneous Fe-Ti ordering and anti-ordering. Separation begins near interfaces between growing ordered and anti-ordered domains, the latter becoming progressively enriched in ilmenite component, moving the Ti-impoverished hematite component into Fe-enriched diffusion waves near the interfaces. Even when disordered regions are eliminated, Fe-enriched waves persist and enlarge on anti-phase boundaries between growing and shrinking ordered and anti-ordered domains. Magnetic results and conceptual models show that magnetic ordering with falling T initiates in the Fe-enriched wave crests. Although representing only a tiny fraction of material, identified at highest Ts on a field-cooling curve, they control the `pre-destiny' of progressive magnetization at lower T. They can provide a positive magnetic moment in a minority of ordered ferrimagnetic material, which, by exchange coupling, then creates a self-reversed negative moment in the remaining majority. Four Ts or T ranges are recognized on typical field-cooling curves: TPD is the T range of `pre-destination'; TC is the predominant Curie T where major positive magnetization increases sharply; TMAX is where magnetization reaches a positive maximum, beyond which it is outweighed by self-reversed magnetization and TZM is the T where total magnetization passes zero. Disposition of these Ts on cooling curves indicate the fine structure of self-reversed thermoremanent magnetization. These results confirm much earlier suspicions that the `x-phase' responsible for self-reversed magnetization resides in Fe-enriched phase boundaries.

Selection of an early biomarker for vascular normalization using dynamic contrast-enhanced ultrasonography to predict outcomes of metastatic patients treated with bevacizumab

PubMed Central

Lassau, N.; Coiffier, B.; Kind, M.; Vilgrain, V.; Lacroix, J.; Cuinet, M.; Taieb, S.; Aziza, R.; Sarran, A.; Labbe-Devilliers, C.; Gallix, B.; Lucidarme, O.; Ptak, Y.; Rocher, L.; Caquot, L. M.; Chagnon, S.; Marion, D.; Luciani, A.; Feutray, S.; Uzan-Augui, J.; Benatsou, B.; Bonastre, J.; Koscielny, S.

2016-01-01

Background Dynamic contrast-enhanced ultrasonography (DCE-US) has been used for evaluation of tumor response to antiangiogenic treatments. The objective of this study was to assess the link between DCE-US data obtained during the first week of treatment and subsequent tumor progression. Patients and methods Patients treated with antiangiogenic therapies were included in a multicentric prospective study from 2007 to 2010. DCE-US examinations were available at baseline and at day 7. For each examination, a 3 min perfusion curve was recorded just after injection of a contrast agent. Each perfusion curve was modeled with seven parameters. We analyzed the correlation between criteria measured up to day 7 on freedom from progression (FFP). The impact was assessed globally, according to tumor localization and to type of treatment. Results The median follow-up was 20 months. The mean transit time (MTT) evaluated at day 7 was the only criterion significantly associated with FFP (P = 0.002). The cut-off point maximizing the difference between FFP curves was 12 s. Patients with at least a 12 s MTT had a better FFP. The results according to tumor type were significantly heterogeneous: the impact of MTT on FFP was more marked for breast cancer (P = 0.004) and for colon cancer (P = 0.025) than for other tumor types. Similarly, the differences in FFP according to MTT at day 7 were marked (P = 0.004) in patients receiving bevacizumab. Conclusion The MTT evaluated with DCE-US at day 7 is significantly correlated to FFP of patients treated with bevacizumab. This criterion might be linked to vascular normalization. AFSSAPS No 2007-A00399-44. PMID:27502701

Ply cracking in composite laminates

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

Han, Youngmyong.

1989-01-01

Ply cracking behavior and accompanying stiffness changes in thermoset as well as thermoplastic matrix composites under various loading conditions are investigated. Specific topics addressed are: analytical model development for property degradations due to ply cracking under general in-plane loading; crack initiation and multiplication under static loading; and crack multiplication under cyclic loading. A model was developed to calculate the energy released due to ply cracking in a composite laminate subjected to general in-plane loading. The method is based on the use of a second order polynomial to represent the crack opening displacement and the concept of a through-the-thickness inherent flaw.more » The model is then used in conjunction with linear elastic fracture mechanics to predict the progressive ply cracking as well as first ply cracking. A resistance curve for crack multiplication is proposed as a means of characterizing the resistance to ply cracking in composite laminates. A methodology of utilizing the resistance curve to assess the crack density or overloading is also discussed. The method was applied to the graphite/thermoplastic polyimide composite to predict progressive ply cracking. However, unlike the thermoset matrix composites, a strength model is found to fit the experimental results better than the fracture mechanics based model. A set of closed form equations is also developed to calculate the accompanying stiffness changes due to the ply cracking. The effect of thermal residual stress is included in the analysis. A new method is proposed to characterize transverse ply cracking of symmetric balanced laminates under cyclic loading. The method is based on the concept of a through-the-thickness inherent flaw, the Paris law, and the resistance curve. Only two constants are needed to predict the crack density as a function of fatigue cycles.« less

Combined measurement of plasma cystatin C and low-density lipoprotein cholesterol: A valuable tool for evaluating progressive supranuclear palsy.

PubMed

Weng, Ruihui; Wei, Xiaobo; Yu, Bin; Zhu, Shuzhen; Yang, Xiaohua; Xie, Fen; Zhang, Mahui; Jiang, Ying; Feng, Zhong-Ping; Sun, Hong-Shuo; Xia, Ying; Jin, Kunlin; Chan, Piu; Wang, Qing; Gao, Xiaoya

2018-07-01

Progressive supranuclear palsy (PSP) was previously thought as a cause of atypical Parkinsonism. Although Cystatin C (Cys C) and low-density cholesterol lipoprotein-C (LDL-C) are known to play critical roles in Parkinsonism, it is unknown whether they can be used as markers to distinguish PSP patients from healthy subjects and to determine disease severity. We conducted a cross-sectional study to determine plasma Cys C/HDL/LDL-C levels of 40 patients with PSP and 40 healthy age-matched controls. An extended battery of motor and neuropsychological tests, including the PSP-Rating Scale (PSPRS), the Non-Motor Symptoms Scale (NMSS), Geriatric Depression Scale (GDS) and Mini-Mental State Examination (MMSE), was used to evaluate the disease severity. Receiver operating characteristic (ROC) curves were adopted to assess the prognostic accuracy of Cys C/LDL-C levels in distinguishing PSP from healthy subjects. Patients with PSP exhibited significantly higher plasma levels of Cys C and lower LDL-C. The levels of plasma Cys C were positively and inversely correlated with the PSPRS/NMSS and MMSE scores, respectively. The LDL-C/HDL-C ratio was positively associated with PSPRS/NMSS and GDS scores. The ROC curve for the combination of Cys C and LDL-C yielded a better accuracy for distinguishing PSP from healthy subjects than the separate curves for each parameter. Plasma Cys C and LDL-C may be valuable screening tools for differentiating PSP from healthy subjects; while they could be useful for the PSP intensifies and severity evaluation. A better understanding of Cys C and LDL-C may yield insights into the pathogenesis of PSP. Copyright © 2018 Elsevier Ltd. All rights reserved.

Determination of Flavonoids in Wine by High Performance Liquid Chromatography

NASA Astrophysics Data System (ADS)

da Queija, Celeste; Queirós, M. A.; Rodrigues, Ligia M.

2001-02-01

The experiment presented is an application of HPLC to the analysis of flavonoids in wines, designed for students of instrumental methods. It is done in two successive 4-hour laboratory sessions. While the hydrolysis of the wines is in progress, the students prepare the calibration curves with standard solutions of flavonoids and calculate the regression lines and correlation coefficients. During the second session they analyze the hydrolyzed wine samples and calculate the concentrations of the flavonoids using the calibration curves obtained earlier. This laboratory work is very attractive to students because they deal with a common daily product whose components are reported to have preventive and therapeutic effects. Furthermore, students can execute preparative work and apply a more elaborate technique that is nowadays an indispensable tool in instrumental analysis.

Multiresolution and Explicit Methods for Vector Field Analysis and Visualization

NASA Technical Reports Server (NTRS)

Nielson, Gregory M.

1997-01-01

This is a request for a second renewal (3d year of funding) of a research project on the topic of multiresolution and explicit methods for vector field analysis and visualization. In this report, we describe the progress made on this research project during the second year and give a statement of the planned research for the third year. There are two aspects to this research project. The first is concerned with the development of techniques for computing tangent curves for use in visualizing flow fields. The second aspect of the research project is concerned with the development of multiresolution methods for curvilinear grids and their use as tools for visualization, analysis and archiving of flow data. We report on our work on the development of numerical methods for tangent curve computation first.

Derivation of genetic biomarkers for cancer risk stratification in Barrett's oesophagus: a prospective cohort study.

PubMed

Timmer, Margriet R; Martinez, Pierre; Lau, Chiu T; Westra, Wytske M; Calpe, Silvia; Rygiel, Agnieszka M; Rosmolen, Wilda D; Meijer, Sybren L; Ten Kate, Fiebo J W; Dijkgraaf, Marcel G W; Mallant-Hent, Rosalie C; Naber, Anton H J; van Oijen, Arnoud H A M; Baak, Lubbertus C; Scholten, Pieter; Böhmer, Clarisse J M; Fockens, Paul; Maley, Carlo C; Graham, Trevor A; Bergman, Jacques J G H M; Krishnadath, Kausilia K

2016-10-01

The risk of developing adenocarcinoma in non-dysplastic Barrett's oesophagus is low and difficult to predict. Accurate tools for risk stratification are needed to increase the efficiency of surveillance. We aimed to develop a prediction model for progression using clinical variables and genetic markers. In a prospective cohort of patients with non-dysplastic Barrett's oesophagus, we evaluated six molecular markers: p16, p53, Her-2/neu, 20q, MYC and aneusomy by DNA fluorescence in situ hybridisation on brush cytology specimens. Primary study outcomes were the development of high-grade dysplasia or oesophageal adenocarcinoma. The most predictive clinical variables and markers were determined using Cox proportional-hazards models, receiver operating characteristic curves and a leave-one-out analysis. A total of 428 patients participated (345 men; median age 60 years) with a cumulative follow-up of 2019 patient-years (median 45 months per patient). Of these patients, 22 progressed; nine developed high-grade dysplasia and 13 oesophageal adenocarcinoma. The clinical variables, age and circumferential Barrett's length, and the markers, p16 loss, MYC gain and aneusomy, were significantly associated with progression on univariate analysis. We defined an 'Abnormal Marker Count' that counted abnormalities in p16, MYC and aneusomy, which significantly improved risk prediction beyond using just age and Barrett's length. In multivariate analysis, these three factors identified a high-risk group with an 8.7-fold (95% CI 2.6 to 29.8) increased HR when compared with the low-risk group, with an area under the curve of 0.76 (95% CI 0.66 to 0.86). A prediction model based on age, Barrett's length and the markers p16, MYC and aneusomy determines progression risk in non-dysplastic Barrett's oesophagus. 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/

General Theory of the Steady Motion of an Airplane

NASA Technical Reports Server (NTRS)

De Bothezat, George

1921-01-01

The writer points out briefly the history of the method proposed for the study of steady motion of an airplane, which is different from other methods now used. M. Paul Painleve has shown how convenient the drag-lift curve was for the study of airplane steady motion. The author later added to the drift-lift curve the curve called the "speed curve" which permits a direct checking of the speed of the airplane under all flying conditions. But the speed curve was plotted in the same quadrant as the drag-lift curve. Later, with the progressive development of aeronautical science, and with the continually increasing knowledge concerning engines and propellers, the author was brought to add the three other quadrants to the original quadrant, and thus was obtained the steady motion chart which is described in detail in this report. This charts permits one to read directly for a given airplane its horizontal speed at any altitude, its rate of climb at any altitude, its apparent inclination to the horizon at any moment, its ceiling, its propeller thrust, revolutions, efficiency, and power absorbed, that is the complete set of quantities involved in the subject, and to follow the variations of all these quantities both for variable altitude and for variable throttle. The chart also permits one to follow the variation of all of the above in flight as a function of the lift coefficient and of the speed. The author also discusses the interaction of the airplane and propeller through the slipstream and the question of the properties of the engine-propeller system and its dependence upon the properties of the engine considered alone and of the propeller considered alone. There is also a discussion of a standard atmosphere.

Robotic partial nephrectomy - Evaluation of the impact of case mix on the procedural learning curve.

PubMed

Roman, A; Ahmed, K; Challacombe, B

2016-05-01

Although Robotic partial nephrectomy (RPN) is an emerging technique for the management of small renal masses, this approach is technically demanding. To date, there is limited data on the nature and progression of the learning curve in RPN. To analyse the impact of case mix on the RPN LC and to model the learning curve. The records of the first 100 RPN performed, were analysed at our institution that were carried out by a single surgeon (B.C) (June 2010-December 2013). Cases were split based on their Preoperative Aspects and Dimensions Used for an Anatomical (PADUA) score into the following groups: 6-7, 8-9 and >10. Using a split group (20 patients in each group) and incremental analysis, the mean, the curve of best fit and R(2) values were calculated for each group. Of 100 patients (F:28, M:72), the mean age was 56.4 ± 11.9 years. The number of patients in each PADUA score groups: 6-7, 8-9 and >10 were 61, 32 and 7 respectively. An increase in incidence of more complex cases throughout the cohort was evident within the 8-9 group (2010: 1 case, 2013: 16 cases). The learning process did not significantly affect the proxies used to assess surgical proficiency in this study (operative time and warm ischaemia time). Case difficulty is an important parameter that should be considered when evaluating procedural learning curves. There is not one well fitting model that can be used to model the learning curve. With increasing experience, clinicians tend to operate on more difficult cases. Copyright © 2016 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Development of Real Time Ultrasonic Imaging

DTIC Science & Technology

1999-01-01

piezoelectric material known as poly vinyl difluoride ( PVDF ) which enables the conversion of mechanical energy to charge the CCD chip. The system...geometries such as curved (wing) surfaces. Other future applications might include heavy gauge welds in plate, corrosion in piping, welds in piping...Harrison, G. "A Novel High Speed, High Resolution Ultrasound Imaging System", QNDE Review of Progress In Quantitative NDE, Plenum Press, Volume 17B, pp

Incremental rate of prefrontal oxygenation determines performance speed during cognitive Stroop test: the effect of ageing.

PubMed

Endo, Kana; Liang, Nan; Idesako, Mitsuhiro; Ishii, Kei; Matsukawa, Kanji

2018-02-19

Cognitive function declines with age. The underlying mechanisms responsible for the deterioration of cognitive performance, however, remain poorly understood. We hypothesized that an incremental rate of prefrontal oxygenation during a cognitive Stroop test decreases in progress of ageing, resulting in a slowdown of cognitive performance. To test this hypothesis, we identified, using multichannel near-infrared spectroscopy, the characteristics of the oxygenated-hemoglobin concentration (Oxy-Hb) responses of the prefrontal cortex to both incongruent Stroop and congruent word-reading test. Spatial distributions of the significant changes in the three components (initial slope, peak amplitude, and area under the curve) of the Oxy-Hb response were compared between young and elderly subjects. The Stroop interference time (as a difference in total periods for executing Stroop and word-reading test, respectively) approximately doubled in elderly as compared to young subjects. The Oxy-Hb in the rostrolateral, but not caudal, prefrontal cortex increased during the Stroop test in both age groups. The initial slope of the Oxy-Hb response, rather than the peak and area under the curve, had a strong correlation with cognitive performance speed. Taken together, it is likely that the incremental rate of prefrontal oxygenation may decrease in progress of ageing, resulting in a decline in cognitive performance.

Reference interaction site model and optimized perturbation theories of colloidal dumbbells with increasing anisotropy

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

Munaò, Gianmarco, E-mail: gmunao@unime.it; Costa, Dino; Caccamo, Carlo

We investigate thermodynamic properties of anisotropic colloidal dumbbells in the frameworks provided by the Reference Interaction Site Model (RISM) theory and an Optimized Perturbation Theory (OPT), this latter based on a fourth-order high-temperature perturbative expansion of the free energy, recently generalized to molecular fluids. Our model is constituted by two identical tangent hard spheres surrounded by square-well attractions with same widths and progressively different depths. Gas-liquid coexistence curves are obtained by predicting pressures, free energies, and chemical potentials. In comparison with previous simulation results, RISM and OPT agree in reproducing the progressive reduction of the gas-liquid phase separation as themore » anisotropy of the interaction potential becomes more pronounced; in particular, the RISM theory provides reasonable predictions for all coexistence curves, bar the strong anisotropy regime, whereas OPT performs generally less well. Both theories predict a linear dependence of the critical temperature on the interaction strength, reproducing in this way the mean-field behavior observed in simulations; the critical density—that drastically drops as the anisotropy increases—turns to be less accurate. Our results appear as a robust benchmark for further theoretical studies, in support to the simulation approach, of self-assembly in model colloidal systems.« less

Space-time windowing of angle-beam wavefield data to characterize scattering from defects

NASA Astrophysics Data System (ADS)

Weng, Yu; Michaels, Jennifer E.

2018-04-01

The primary focus of ultrasonic nondestructive evaluation is defect detection and characterization. In particular, fatigue cracks emanating from fastener holes are commonly found in aerospace structures. Therefore, scattering of ultrasonic waves from crack-like notches is of practical interest. Here, angle-beam shear waves are used to interrogate notches in aluminum plates. In prior work, notch-scattering was characterized and quantified in the frequency-wavenumber domain, which has the undesirable effect of lumping all scattered shear wave energy from notches into a single energy curve. This present work focuses on developing space-time windowing methods to quantify notch-scattered energy directly in the time-space domain. Two strategies are developed. The first is to indirectly characterize notch-scattering via the change in scattering as compared to the undamaged through-hole. The second strategy is to directly track notch-scattered waves in the time-space domain and then quantify scattered energy by constructing energy-versus-direction curves. Both strategies provide a group of energy difference curves, which show how notch-scattering evolves as time progresses. Notch-scattering quantification results for different notch lengths are shown and discussed.

Holocene sea-level changes along the Strait of Magellan and Beagle Channel, southernmost South America

NASA Astrophysics Data System (ADS)

Porter, Stephen C.; Stuiver, Minze; Heusser, Calvin J.

1984-07-01

Radiocarbon-dated marine sediments from five coastal sites along the Strait of Magellan and Beagle Channel in southernmost Chile permit construction of a curve of relative sea-level fluctuations during the Holocene. Morphologic and stratigraphic data point to coastal submergence during the early Holocene as the sea rose to a maximum level at least 3.5 m higher than present about 5000 yr ago. Progressive emergence then followed during the late Holocene. Data from widely separated localities define a smooth curve, the form of which is explainable in terms of isostatic and hydroisostatic deformation of the crust resulting from changing ice and water loads. Apparently anomalous data from one site located more than 100 km behind the outer limit of the last glaciation may reflect isostatic response to deglaciation. The sea-level curve resembles one derived by Clark and Bloom (1979, In "Proceedings of the 1978 International Symposium on Coastal Evolution in the Quaternary, Sao Paulo, Brasil," pp. 41-60. Sao Paulo) using a spherical Earth model, both in amplitude and in the timing of the maximum submergence.

Neural blockade during exercise augments central command's contribution to carotid baroreflex resetting

NASA Technical Reports Server (NTRS)

Querry, R. G.; Smith, S. A.; Stromstad, M.; Ide, K.; Raven, P. B.; Secher, N. H.

2001-01-01

This investigation was designed to determine central command's role on carotid baroreflex (CBR) resetting during exercise. Nine volunteer subjects performed static and rhythmic handgrip exercise at 30 and 40% maximal voluntary contraction (MVC), respectively, before and after partial axillary neural blockade. Stimulus-response curves were developed using the neck pressure-neck suction technique and a rapid pulse train protocol (+40 to -80 Torr). Regional anesthesia resulted in a significant reduction in MVC. Heart rate (HR) and ratings of perceived exertion (RPE) were used as indexes of central command and were elevated during exercise at control force intensity after induced muscle weakness. The CBR function curves were reset vertically with a minimal lateral shift during control exercise and exhibited a further parallel resetting during exercise with neural blockade. The operating point was progressively reset to coincide with the centering point of the CBR curve. These data suggest that central command was a primary mechanism in the resetting of the CBR during exercise. However, it appeared that central command modulated the carotid-cardiac reflex proportionately more than the carotid-vasomotor reflex.

Emphysema Distribution and Diffusion Capacity Predict Emphysema Progression in Human Immunodeficiency Virus Infection

PubMed Central

Leung, Janice M; Malagoli, Andrea; Santoro, Antonella; Besutti, Giulia; Ligabue, Guido; Scaglioni, Riccardo; Dai, Darlene; Hague, Cameron; Leipsic, Jonathon; Sin, Don D.; Man, SF Paul; Guaraldi, Giovanni

2016-01-01

Background Chronic obstructive pulmonary disease (COPD) and emphysema are common amongst patients with human immunodeficiency virus (HIV). We sought to determine the clinical factors that are associated with emphysema progression in HIV. Methods 345 HIV-infected patients enrolled in an outpatient HIV metabolic clinic with ≥2 chest computed tomography scans made up the study cohort. Images were qualitatively scored for emphysema based on percentage involvement of the lung. Emphysema progression was defined as any increase in emphysema score over the study period. Univariate analyses of clinical, respiratory, and laboratory data, as well as multivariable logistic regression models, were performed to determine clinical features significantly associated with emphysema progression. Results 17.4% of the cohort were emphysema progressors. Emphysema progression was most strongly associated with having a low baseline diffusion capacity of carbon monoxide (DLCO) and having combination centrilobular and paraseptal emphysema distribution. In adjusted models, the odds ratio (OR) for emphysema progression for every 10% increase in DLCO percent predicted was 0.58 (95% confidence interval [CI] 0.41–0.81). The equivalent OR (95% CI) for centrilobular and paraseptal emphysema distribution was 10.60 (2.93–48.98). Together, these variables had an area under the curve (AUC) statistic of 0.85 for predicting emphysema progression. This was an improvement over the performance of spirometry (forced expiratory volume in 1 second to forced vital capacity ratio), which predicted emphysema progression with an AUC of only 0.65. Conclusion Combined paraseptal and centrilobular emphysema distribution and low DLCO could identify HIV patients who may experience emphysema progression. PMID:27902753

Starspots on V711 Tauri /HR 1099/

NASA Astrophysics Data System (ADS)

Dorren, J. D.; Siah, M. J.; Guinan, E. F.; McCook, G. P.

1981-04-01

Hα (λ6563) intermediate- and narrowband light curves of the RS CVn-type binary system V711 Tau (HR 1099) were obtained in 1977-1978 at Biruni Observatory and in 1977-1978 and late 1979 at Villanova Observatory, where a λ7790 light curve was also obtained in 1977-1978. The light curves are quasisinusoidal, with a period approximately equal to the spectroscopic period. A significant change in the λ6585 light curve occurred between the two observing seasons, with an increase in amplitude from 0.075 to 0.125 mag, a change of shape, and an advance in the phases of maximum and minimum light by 0.3 phase. Flaring activity in Hα was observed, on time scales from minutes to days. We fitted our light curves and V-band light curves obtained at the same time using the starspot model of Torres and Ferraz Mello. We the observed light variations are due to the synchronous rotation of spots on the heavier member of the binary system, which has been shown to be the chromospherically active star. The orbital inclination was assumed to be 35°. Radiant fluxes were taken from spectrophotometric tables. Owing to the broad wavelength coverage in 1977-1978, it was possible to determine the spot temperature to be ˜1800 K cooler than the photosphere, and hence to fix the spot area. A simple model with two circular spots of 26° radius at the same latitude, +48°, adequately reproduces the 1977-1978 light curves. The 1979 observations can be reproduced in detail by a model with two slightly larger circular spots of 31°.5 radius at latitude +15°. The spots cover about 14% of the total stellar surface in 1979. The fits also provide an explanation of the presence of an observed phase dependence in the Hα emission in 1979 but not in 1977-1978. There is a strong suggestion that a spot cycle is in progress in V711 Tau.

A century of enzyme kinetic analysis, 1913 to 2013.

PubMed

Johnson, Kenneth A

2013-09-02

This review traces the history and logical progression of methods for quantitative analysis of enzyme kinetics from the 1913 Michaelis and Menten paper to the application of modern computational methods today. Following a brief review of methods for fitting steady state kinetic data, modern methods are highlighted for fitting full progress curve kinetics based upon numerical integration of rate equations, including a re-analysis of the original Michaelis-Menten full time course kinetic data. Finally, several illustrations of modern transient state kinetic methods of analysis are shown which enable the elucidation of reactions occurring at the active sites of enzymes in order to relate structure and function. Copyright © 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Application of fiber grating-based acoustic sensor in progressive failure testing of e-glass/vinylester curve composites

NASA Astrophysics Data System (ADS)

Azmi, Asrul Izam; Raju, Raju; Peng, Gang-Ding

2012-02-01

This paper reports an application of phase shifted fiber Bragg grating (PS-FBG) intensity-type acoustic sensor in a continuous and in-situ failure testing of an E-glass/vinylester top hat stiffener (THS). The narrow transmission channel of the PS-FBG is highly sensitive to small perturbation, hence suitable to be used in an effective acoustic emission (AE) assessment technique. The progressive failure of THS was tested under transverse loading to experimentally simulate the actual loading in practice. Our experimental tests have demonstrated, in good agreement with the commercial piezoelectric sensors, that the important failures information of the THS was successfully recorded by the simple intensity-type PS-FBG sensor.

Unsupervised Gaussian Mixture-Model With Expectation Maximization for Detecting Glaucomatous Progression in Standard Automated Perimetry Visual Fields.

PubMed

Yousefi, Siamak; Balasubramanian, Madhusudhanan; Goldbaum, Michael H; Medeiros, Felipe A; Zangwill, Linda M; Weinreb, Robert N; Liebmann, Jeffrey M; Girkin, Christopher A; Bowd, Christopher

2016-05-01

To validate Gaussian mixture-model with expectation maximization (GEM) and variational Bayesian independent component analysis mixture-models (VIM) for detecting glaucomatous progression along visual field (VF) defect patterns (GEM-progression of patterns (POP) and VIM-POP). To compare GEM-POP and VIM-POP with other methods. GEM and VIM models separated cross-sectional abnormal VFs from 859 eyes and normal VFs from 1117 eyes into abnormal and normal clusters. Clusters were decomposed into independent axes. The confidence limit (CL) of stability was established for each axis with a set of 84 stable eyes. Sensitivity for detecting progression was assessed in a sample of 83 eyes with known progressive glaucomatous optic neuropathy (PGON). Eyes were classified as progressed if any defect pattern progressed beyond the CL of stability. Performance of GEM-POP and VIM-POP was compared to point-wise linear regression (PLR), permutation analysis of PLR (PoPLR), and linear regression (LR) of mean deviation (MD), and visual field index (VFI). Sensitivity and specificity for detecting glaucomatous VFs were 89.9% and 93.8%, respectively, for GEM and 93.0% and 97.0%, respectively, for VIM. Receiver operating characteristic (ROC) curve areas for classifying progressed eyes were 0.82 for VIM-POP, 0.86 for GEM-POP, 0.81 for PoPLR, 0.69 for LR of MD, and 0.76 for LR of VFI. GEM-POP was significantly more sensitive to PGON than PoPLR and linear regression of MD and VFI in our sample, while providing localized progression information. Detection of glaucomatous progression can be improved by assessing longitudinal changes in localized patterns of glaucomatous defect identified by unsupervised machine learning.

Progression of the first stage of spontaneous labour: A prospective cohort study in two sub-Saharan African countries

PubMed Central

Fawole, Bukola; Mugerwa, Kidza; Alves, Domingos; Souza, Hayala; Reis, Rodrigo; Oliveira-Ciabati, Livia; Maiorano, Alexandre; Akintan, Adesina; Alu, Francis E.; Oyeneyin, Lawal; Adebayo, Amos; Byamugisha, Josaphat; Idris, Hadiza A.; Okike, Ola; Althabe, Fernando; Hundley, Vanora; Pattinson, Robert; Sanghvi, Harshadkumar C.; Tunçalp, Özge; Vogel, Joshua P.; Stanton, Mary Ellen; Liljestrand, Jerker; ten Hoope-Bender, Petra; Mathai, Matthews; Bahl, Rajiv

2018-01-01

Background Escalation in the global rates of labour interventions, particularly cesarean section and oxytocin augmentation, has renewed interest in a better understanding of natural labour progression. Methodological advancements in statistical and computational techniques addressing the limitations of pioneer studies have led to novel findings and triggered a re-evaluation of current labour practices. As part of the World Health Organization's Better Outcomes in Labour Difficulty (BOLD) project, which aimed to develop a new labour monitoring-to-action tool, we examined the patterns of labour progression as depicted by cervical dilatation over time in a cohort of women in Nigeria and Uganda who gave birth vaginally following a spontaneous labour onset. Methods and findings This was a prospective, multicentre, cohort study of 5,606 women with singleton, vertex, term gestation who presented at ≤ 6 cm of cervical dilatation following a spontaneous labour onset that resulted in a vaginal birth with no adverse birth outcomes in 13 hospitals across Nigeria and Uganda. We independently applied survival analysis and multistate Markov models to estimate the duration of labour centimetre by centimetre until 10 cm and the cumulative duration of labour from the cervical dilatation at admission through 10 cm. Multistate Markov and nonlinear mixed models were separately used to construct average labour curves. All analyses were conducted according to three parity groups: parity = 0 (n = 2,166), parity = 1 (n = 1,488), and parity = 2+ (n = 1,952). We performed sensitivity analyses to assess the impact of oxytocin augmentation on labour progression by re-examining the progression patterns after excluding women with augmented labours. Labour was augmented with oxytocin in 40% of nulliparous and 28% of multiparous women. The median time to advance by 1 cm exceeded 1 hour until 5 cm was reached in both nulliparous and multiparous women. Based on a 95th percentile threshold, nulliparous women may take up to 7 hours to progress from 4 to 5 cm and over 3 hours to progress from 5 to 6 cm. Median cumulative duration of labour indicates that nulliparous women admitted at 4 cm, 5 cm, and 6 cm reached 10 cm within an expected time frame if the dilatation rate was ≥ 1 cm/hour, but their corresponding 95th percentiles show that labour could last up to 14, 11, and 9 hours, respectively. Substantial differences exist between actual plots of labour progression of individual women and the ‘average labour curves’ derived from study population-level data. Exclusion of women with augmented labours from the study population resulted in slightly faster labour progression patterns. Conclusions Cervical dilatation during labour in the slowest-yet-normal women can progress more slowly than the widely accepted benchmark of 1 cm/hour, irrespective of parity. Interventions to expedite labour to conform to a cervical dilatation threshold of 1 cm/hour may be inappropriate, especially when applied before 5 cm in nulliparous and multiparous women. Averaged labour curves may not truly reflect the variability associated with labour progression, and their use for decision-making in labour management should be de-emphasized. PMID:29338000

Novel white matter tract integrity metrics sensitive to Alzheimer disease progression.

PubMed

Fieremans, E; Benitez, A; Jensen, J H; Falangola, M F; Tabesh, A; Deardorff, R L; Spampinato, M V S; Babb, J S; Novikov, D S; Ferris, S H; Helpern, J A

2013-01-01

Along with cortical abnormalities, white matter microstructural changes such as axonal loss and myelin breakdown are implicated in the pathogenesis of Alzheimer disease. Recently, a white matter model was introduced that relates non-Gaussian diffusional kurtosis imaging metrics to characteristics of white matter tract integrity, including the axonal water fraction, the intra-axonal diffusivity, and the extra-axonal axial and radial diffusivities. This study reports these white matter tract integrity metrics in subjects with amnestic mild cognitive impairment (n = 12), Alzheimer disease (n = 14), and age-matched healthy controls (n = 15) in an effort to investigate their sensitivity, diagnostic accuracy, and associations with white matter changes through the course of Alzheimer disease. With tract-based spatial statistics and region-of-interest analyses, increased diffusivity in the extra-axonal space (extra-axonal axial and radial diffusivities) in several white matter tracts sensitively and accurately discriminated healthy controls from those with amnestic mild cognitive impairment (area under the receiver operating characteristic curve = 0.82-0.95), while widespread decreased axonal water fraction discriminated amnestic mild cognitive impairment from Alzheimer disease (area under the receiver operating characteristic curve = 0.84). Additionally, these white matter tract integrity metrics in the body of the corpus callosum were strongly correlated with processing speed in amnestic mild cognitive impairment (r = |0.80-0.82|, P < .001). These findings have implications for the course and spatial progression of white matter degeneration in Alzheimer disease, suggest the mechanisms by which these changes occur, and demonstrate the viability of these white matter tract integrity metrics as potential neuroimaging biomarkers of the earliest stages of Alzheimer disease and disease progression.

Behavioural, brain and cardiac responses to hypobaric hypoxia in broiler chickens.

PubMed

Martin, Jessica E; Christensen, Karen; Vizzier-Thaxton, Yvonne; Mitchell, Malcolm A; McKeegan, Dorothy E F

2016-09-01

A novel approach to pre-slaughter stunning of chickens has been developed in which birds are rendered unconscious by progressive hypobaric hypoxia. Termed Low Atmospheric Pressure Stunning (LAPS), this approach involves application of gradual decompression lasting 280s according to a prescribed curve. We examined responses to LAPS by recording behaviour, electroencephalogram (EEG) and electrocardiogram (ECG) in individual male chickens, and interpreted these with regard to the welfare impact of the process. We also examined the effect of two temperature adjusted pressure curves on these responses. Broiler chickens were exposed to LAPS in 30 triplets (16 and 14 triplets assigned to each pressure curve). In each triplet, one bird was instrumented for recording of EEG and ECG while the behaviour of all three birds was observed. Birds showed a consistent sequence of behaviours during LAPS (ataxia, loss of posture, clonic convulsions and motionless) which were observed in all birds. Leg paddling, tonic convulsions, slow wing flapping, mandibulation, head shaking, open bill breathing, deep inhalation, jumping and vocalisation were observed in a proportion of birds. Spectral analysis of EEG responses at 2s intervals throughout LAPS revealed progressive decreases in median frequency at the same time as corresponding progressive increases in total power, followed later by decreases in total power as all birds exhibited isoelectric EEG and died. There was a very pronounced increase in total power at 50-60s into the LAPS cycle, which corresponded to dominance of the signal by high amplitude slow waves, indicating loss of consciousness. Slow wave EEG was seen early in the LAPS process, before behavioural evidence of loss of consciousness such as ataxia and loss of posture, almost certainly due to the fact that it was completely dark in the LAPS chamber. ECG recordings showed a pronounced bradycardia (starting on average 49.6s into LAPS), often associated with arrhythmia, until around 60s into LAPS when heart rate levelled off. There was a good correlation between behavioural, EEG and cardiac measures in relation to loss of consciousness which collectively provide a loss of consciousness estimate of around 60s. There were some effects of temperature adjusted pressure curves on behavioural latencies and ECG responses, but in general responses were consistent and very similar to those reported in previous research on controlled atmosphere stunning with inert gases. The results suggest that the process is humane (slaughter without avoidable fear, anxiety, pain, suffering and distress). In particular, the maintenance of slow wave EEG patterns in the early part of LAPS (while birds are still conscious) is strongly suggestive that LAPS is non-aversive, since we would expect this to be interrupted by pain or discomfort. Copyright © 2016 Elsevier Inc. All rights reserved.

Latest Progress in High Power VECSELs

DTIC Science & Technology

2013-01-01

are more efficient, and can be tailored to an application. In this manuscript we lay out some advantages to VECSELs as compared to many in-plane...semiconductor lasers. We review common fabrication and packaging techniques in Section 2. In Section 3, we discuss both small- signal and large-signal... out LR coating MQW DBR VECSEL chip Heat Spreader output coupler HR flat mirror BF at Brewster’s angle HR flat mirror HR curved mirror signal beam out

Hemoglobin P50 During a Simulated Ascent of Mt. Everest, Operation Everest II

DTIC Science & Technology

2007-01-01

With altitude, increased [2,3-DPG] shifts the dissociation curve rightward, but hypocap- nia and alkalosis move it leftward. We determined both...of 30 mmHg. However, in vivo P50 remained between 26 and 27 mmHg throughout due to pro- gressive hypocapnia and alkalosis . Calculations suggest that...were unpredictable at extreme altitude, espe- cially in the face of counterbalancing effects from progressive hyperventilation and alkalosis . It was

Motor Learning Curve and Long-Term Effectiveness of Modified Constraint-Induced Movement Therapy in Children with Unilateral Cerebral Palsy: A Randomized Controlled Trial

ERIC Educational Resources Information Center

Geerdink, Yvonne; Aarts, Pauline; Geurts, Alexander C.

2013-01-01

The goal of this study was to determine the progression of manual dexterity during 6 weeks (54 h) (modified) constraint-induced movement therapy ((m)CIMT) followed by 2 weeks (18 h) bimanual training (BiT) in children with unilateral spastic cerebral palsy (CP), to establish whether and when a maximal training effect was reached and which factors…

Surgical treatment and intraoperative spinal cord monitoring in scoliosis associated with chronic inflammatory demyelinating polyneuropathy: A case report

PubMed Central

Miyakoshi, Naohisa; Hongo, Michio; Kasukawa, Yuji; Ishikawa, Yoshinori; Misawa, Akiko; Shimada, Yoichi

2013-01-01

There has been only one reported case of neuromuscular scoliosis following chronic inflammatory demyelinating polyneuropathy (CIDP). However, no cases of scoliosis that were treated with surgery secondary to CIDP have been previously described. A 16-year-old boy with CIDP was consultant due to the progression of scoliosis with the coronal curve of 86° from T8 to T12. Posterior correction and fusion with segmental pedicle screws were performed under intraoperative spinal cord monitoring with transcranial electric motor-evoked potentials. Although the latency period was prolonged and amplitude was low, the potential remained stable. Coronal curve was corrected from 86° to 34° without neurological complications. We here describe scoliosis associated with CIDP, which was successfully treated with surgery under intraoperative spinal cord monitoring. PMID:23311940

Fetal growth in muskoxen determined by transabdominal ultrasonography.

PubMed Central

Pharr, J W; Rowell, J E; Flood, P F

1994-01-01

A 5 MHz commercial sector scanner was used to monitor 13 muskox pregnancies and establish normal fetal growth curves. Examinations were carried out between 40 and 197 days of gestation and pregnancy could be detected throughout the period. Early pregnancies were found by scanning lateral to the udder but as pregnancy progressed the fetus was found closer to the dam's umbilicus. Measurements of cranial and abdominal diameters taken at about two week intervals in seven uncomplicated pregnancies in four cows were used to construct fetal growth curves. These can be reliably used in the reproductive management of muskoxen. In addition a series of regressions based on measurements of the fetuses of muskoxen killed in the Arctic are provided. These allow cranial and abdominal diameters to be related to fetal weight and crown-rump length. Images Fig. 1. Fig. 2. PMID:7954117

Fitting milk production curves through nonlinear mixed models.

PubMed

Piccardi, Monica; Macchiavelli, Raúl; Funes, Ariel Capitaine; Bó, Gabriel A; Balzarini, Mónica

2017-05-01

The aim of this work was to fit and compare three non-linear models (Wood, Milkbot and diphasic) to model lactation curves from two approaches: with and without cow random effect. Knowing the behaviour of lactation curves is critical for decision-making in a dairy farm. Knowledge of the model of milk production progress along each lactation is necessary not only at the mean population level (dairy farm), but also at individual level (cow-lactation). The fits were made in a group of high production and reproduction dairy farms; in first and third lactations in cool seasons. A total of 2167 complete lactations were involved, of which 984 were first-lactations and the remaining ones, third lactations (19 382 milk yield tests). PROC NLMIXED in SAS was used to make the fits and estimate the model parameters. The diphasic model resulted to be computationally complex and barely practical. Regarding the classical Wood and MilkBot models, although the information criteria suggest the selection of MilkBot, the differences in the estimation of production indicators did not show a significant improvement. The Wood model was found to be a good option for fitting the expected value of lactation curves. Furthermore, the three models fitted better when the subject (cow) random effect was considered, which is related to magnitude of production. The random effect improved the predictive potential of the models, but it did not have a significant effect on the production indicators derived from the lactation curves, such as milk yield and days in milk to peak.

ROC curves in clinical chemistry: uses, misuses, and possible solutions.

PubMed

Obuchowski, Nancy A; Lieber, Michael L; Wians, Frank H

2004-07-01

ROC curves have become the standard for describing and comparing the accuracy of diagnostic tests. Not surprisingly, ROC curves are used often by clinical chemists. Our aims were to observe how the accuracy of clinical laboratory diagnostic tests is assessed, compared, and reported in the literature; to identify common problems with the use of ROC curves; and to offer some possible solutions. We reviewed every original work using ROC curves and published in Clinical Chemistry in 2001 or 2002. For each article we recorded phase of the research, prospective or retrospective design, sample size, presence/absence of confidence intervals (CIs), nature of the statistical analysis, and major analysis problems. Of 58 articles, 31% were phase I (exploratory), 50% were phase II (challenge), and 19% were phase III (advanced) studies. The studies increased in sample size from phase I to III and showed a progression in the use of prospective designs. Most phase I studies were powered to assess diagnostic tests with ROC areas >/=0.70. Thirty-eight percent of studies failed to include CIs for diagnostic test accuracy or the CIs were constructed inappropriately. Thirty-three percent of studies provided insufficient analysis for comparing diagnostic tests. Other problems included dichotomization of the gold standard scale and inappropriate analysis of the equivalence of two diagnostic tests. We identify available software and make some suggestions for sample size determination, testing for equivalence in diagnostic accuracy, and alternatives to a dichotomous classification of a continuous-scale gold standard. More methodologic research is needed in areas specific to clinical chemistry.

Ensemble Learning Method for Outlier Detection and its Application to Astronomical Light Curves

NASA Astrophysics Data System (ADS)

Nun, Isadora; Protopapas, Pavlos; Sim, Brandon; Chen, Wesley

2016-09-01

Outlier detection is necessary for automated data analysis, with specific applications spanning almost every domain from financial markets to epidemiology to fraud detection. We introduce a novel mixture of the experts outlier detection model, which uses a dynamically trained, weighted network of five distinct outlier detection methods. After dimensionality reduction, individual outlier detection methods score each data point for “outlierness” in this new feature space. Our model then uses dynamically trained parameters to weigh the scores of each method, allowing for a finalized outlier score. We find that the mixture of experts model performs, on average, better than any single expert model in identifying both artificially and manually picked outliers. This mixture model is applied to a data set of astronomical light curves, after dimensionality reduction via time series feature extraction. Our model was tested using three fields from the MACHO catalog and generated a list of anomalous candidates. We confirm that the outliers detected using this method belong to rare classes, like Novae, He-burning, and red giant stars; other outlier light curves identified have no available information associated with them. To elucidate their nature, we created a website containing the light-curve data and information about these objects. Users can attempt to classify the light curves, give conjectures about their identities, and sign up for follow up messages about the progress made on identifying these objects. This user submitted data can be used further train of our mixture of experts model. Our code is publicly available to all who are interested.

Progression of symptomatic intracranial large artery atherosclerosis is associated with a proinflammatory state and impaired fibrinolysis.

PubMed

Arenillas, Juan F; Alvarez-Sabín, José; Molina, Carlos A; Chacón, Pilar; Fernández-Cadenas, Israel; Ribó, Marc; Delgado, Pilar; Rubiera, Marta; Penalba, Anna; Rovira, Alex; Montaner, Joan

2008-05-01

The molecular pathways involved in the progression of intracranial large artery atherosclerosis (ILA) are largely unknown. Our objective was to prospectively study the relationship between circulating levels of inflammatory markers and fibrinolysis inhibitors, and the risk of progression of symptomatic ILA. Seventy-five consecutive patients with first-ever symptomatic intracranial atherostenosis were studied. Blood levels of C-reactive protein (CRP), E-selectin, monocyte chemoattractant protein-1, intercellular adhesion molecule-1, matrix metalloproteinases 1, 2, 3, 8, 9, 10, and 13, plasminogen activator inhibitor-1 (PAI-1), and lipoprotein(a) were measured 3 months after the qualifying stroke or transient ischemic attack. Thereafter, patients underwent long-term transcranial Doppler follow-up to detect progression of ILA. During a median follow-up time of 23 months, 25 (33%) patients showed ILA progression. Multivariable adjusted Cox regression models and Kaplan-Meier curves showed that high baseline level of CRP, E-selectin, intercellular adhesion molecule-1, matrix metalloproteinase 9, PAI-1, and lipoprotein(a) predicted ILA progression independently of vascular risk factors. Of them, only CRP (CRP>5.5 mg/L; HR, 5.4 [2.3 to 12.7]; P=0.0001) and PAI-1 (PAI-1>23.1 ng/mL; HR, 2.4 [1.0 to 5.8]; P=0.05) predicted ILA progression also independently of the other studied molecules. Progression of symptomatic ILA is associated with a proinflammatory state, as reflected by high levels of inflammatory markers, and with defective fibrinolysis, as indicated by raised concentrations of endogenous fibrinolysis inhibitors.

Ultrasonographic wall thickness measurement of the upper and lower uterine segments in the prediction of the progress of preterm labour.

PubMed

Sayed Ahmed, W A; Madny, E H; Habash, Y H; Ibrahim, Z M; Morsy, A G K; Said, M E

2015-01-01

To assess the role of ultrasonographic measurement of the upper and lower uterine segments wall thickness in predicting the progress of preterm labour in patients presenting with preterm labour pains. Fifty pregnant women presenting at Obstetrics Department - Suez Canal University, Egypt with regular lower abdominal pains and diagnosed as having preterm labour were enrolled in the study. Measurements of the upper and lower uterine segments wall thickness by transabdominal ultrasonography in-between contractions and with full bladder were taken. The upper/lower uterine wall thickness ratio was calculated and correlated to the progress of the preterm labour and to the response to tocolytics. The ultrasonographic upper/lower uterine wall thickness ratio was directly related to the progress of preterm delivery (PTD). The change in this ratio is correlated inversely with the response to tocolysis. Using the ROC curve, when the upper/lower uterine wall thickness ratio was ≤ 1.26 the sensitivity was 94.74 and the specificity was 100.00, and when the ratio was ≤ 1.52 the sensitivity was 100.00 and the specificity was 83.33. These data may serve as a baseline ultrasonographic reference values for further studies in prediction the progress of preterm labour in patients presenting with preterm labour pains.

Transvaginal ultrasonographic cervical measurement in predicting failed labor induction and cesarean delivery for failure to progress in nulliparous women.

PubMed

Park, Kyo Hoon

2007-08-01

The aim of this study was to evaluate the value of transvaginal sonographic cervical measurement in predicting failed labor induction and cesarean delivery for failure to progress in nulliparous women. One hundred and sixty-one women scheduled for labor induction underwent transvaginal ultrasonography and digital cervical examinations. Logistic regression demonstrated that cervical length and gestational age at induction, but not the Bishop score, significantly and independently predicted failed labor induction. According to the receiver operating characteristic curves analysis, the best cut-off value of cervical length for predicting failed labor induction was 28 mm, with a sensitivity of 62% and a specificity of 60%. In terms of the likelihood of a cesarean delivery for failure to progress as the outcome variable, logistic regression indicated that maternal height and birth weight, but not cervical length or Bishop score, were significantly and independently associated with an increased risk of cesarean delivery for failure to progress. Transvaginal sonographic measurements of cervical length thus independently predicted failed labor induction in nulliparous women. However, the relatively poor predictive performance of this test undermines its clinical usefulness as a predictor of failed labor induction. Moreover, cervical length appears to have a poor predictive value for the likelihood of a cesarean delivery for failure to progress.

A Progressive Damage Methodology for Residual Strength Predictions of Notched Composite Panels

NASA Technical Reports Server (NTRS)

Coats, Timothy W.; Harris, Charles E.

1998-01-01

The translaminate fracture behavior of carbon/epoxy structural laminates with through-penetration notches was investigated to develop a residual strength prediction methodology for composite structures. An experimental characterization of several composite materials systems revealed a fracture resistance behavior that was very similar to the R-curve behavior exhibited by ductile metals. Fractographic examinations led to the postulate that the damage growth resistance was primarily due to fractured fibers in the principal load-carrying plies being bridged by intact fibers of the adjacent plies. The load transfer associated with this bridging mechanism suggests that a progressive damage analysis methodology will be appropriate for predicting the residual strength of laminates with through-penetration notches. A progressive damage methodology developed by the authors was used to predict the initiation and growth of matrix cracks and fiber fracture. Most of the residual strength predictions for different panel widths, notch lengths, and material systems were within about 10% of the experimental failure loads.

Improvement of Progressive Damage Model to Predicting Crashworthy Composite Corrugated Plate

NASA Astrophysics Data System (ADS)

Ren, Yiru; Jiang, Hongyong; Ji, Wenyuan; Zhang, Hanyu; Xiang, Jinwu; Yuan, Fuh-Gwo

2018-02-01

To predict the crashworthy composite corrugated plate, different single and stacked shell models are evaluated and compared, and a stacked shell progressive damage model combined with continuum damage mechanics is proposed and investigated. To simulate and predict the failure behavior, both of the intra- and inter- laminar failure behavior are considered. The tiebreak contact method, 1D spot weld element and cohesive element are adopted in stacked shell model, and a surface-based cohesive behavior is used to capture delamination in the proposed model. The impact load and failure behavior of purposed and conventional progressive damage models are demonstrated. Results show that the single shell could simulate the impact load curve without the delamination simulation ability. The general stacked shell model could simulate the interlaminar failure behavior. The improved stacked shell model with continuum damage mechanics and cohesive element not only agree well with the impact load, but also capture the fiber, matrix debonding, and interlaminar failure of composite structure.

Does information available at admission for delivery improve prediction of vaginal birth after cesarean?

PubMed Central

Grobman, William A.; Lai, Yinglei; Landon, Mark B.; Spong, Catherine Y.; Leveno, Kenneth J.; Rouse, Dwight J.; Varner, Michael W.; Moawad, Atef H.; Simhan, Hyagriv N.; Harper, Margaret; Wapner, Ronald J.; Sorokin, Yoram; Miodovnik, Menachem; Carpenter, Marshall; O'sullivan, Mary J.; Sibai, Baha M.; Langer, Oded; Thorp, John M.; Ramin, Susan M.; Mercer, Brian M.

2010-01-01

Objective To construct a predictive model for vaginal birth after cesarean (VBAC) that combines factors that can be ascertained only as the pregnancy progresses with those known at initiation of prenatal care. Study design Using multivariable modeling, we constructed a predictive model for VBAC that included patient factors known at the initial prenatal visit as well as those that only became evident as the pregancy progressed to the admission for delivery. Results 9616 women were analyzed. The regression equation for VBAC success included multiple factors that could not be known at the first prenatal visit. The area under the curve for this model was significantly greater (P < .001) than that of a model that included only factors available at the first prenatal visit. Conclusion A prediction model for VBAC success that incorporates factors that can be ascertained only as the pregnancy progresses adds to the predictive accuracy of a model that uses only factors available at a first prenatal visit. PMID:19813165

The impact of curve severity on obstetric complications and regional anesthesia utilization in pregnant patients with adolescent idiopathic scoliosis: a preliminary analysis.

PubMed

Chan, Emily W; Gannon, Stephen R; Shannon, Chevis N; Martus, Jeffrey E; Mencio, Gregory A; Bonfield, Christopher M

2017-10-01

OBJECTIVE Adolescent idiopathic scoliosis (AIS), the most common type of scoliosis, often presents immediately prior to a woman's childbearing years; however, research investigating the impact of AIS on women's health, particularly pregnancy delivery outcomes, is sparse, with existing literature reporting mixed findings. Similarly limited are studies examining the change in scoliotic curve during or after pregnancy. Therefore, this study aims to determine 1) the impact of scoliotic curvature on obstetric complications (preterm births, induction of labor, and urgent/emergency caesarean section delivery), 2) regional anesthetic decision making and success during delivery for these patients, and 3) the effect of pregnancy on curve progression. METHODS Records of all pregnant patients diagnosed with AIS at the authors' institution who delivered between January 2002 and September 2016 were retrospectively reviewed. Demographic information, pre- and postpartum radiographic Cobb angles, and clinical data for each pregnancy and delivery were recorded and analyzed. The Wilcoxon rank-sum test and the Wilcoxon signed-rank test were used for statistical analyses. RESULTS Fifty-nine patients (84 deliveries) were included; 14 patients had undergone prior posterior spinal fusion. The median age at AIS diagnosis was 15.2 years, and the median age at delivery was 21.8 years. Overall, the median major Cobb angle prior to the first pregnancy was 25° (IQR 15°-40°). Most births were by spontaneous vaginal delivery (n = 45; 54%); elective caesarean section was performed in 17 deliveries (20%). Obstetric complications included preterm birth (n = 18; 21.4%), induction of labor (n = 20; 23.8%), and urgent/emergency caesarean section (n = 12; 14.0%); none were associated with severity of scoliosis curve or prior spinal fusion. Attempts at spinal anesthesia were successful 99% of the time (70/71 deliveries), even among the patients who had undergone prior spinal fusion (n = 13). There were only 3 instances of provider refusal to administer spinal anesthesia. In the subset of 11 patients who underwent postpartum scoliosis radiography, there was no statistically significant change in curve magnitude either during or immediately after pregnancy. CONCLUSIONS The results of this study suggest that there was no effect of the severity of scoliosis on delivery complications or regional anesthetic decision making in pregnant patients with AIS. Moreover, scoliosis was not observed to progress significantly during or immediately after pregnancy. Larger prospective studies are needed to further investigate these outcomes, the findings of which can guide the prenatal education and counseling of pregnant patients with AIS.

Apparent diffusion coefficient on magnetic resonance imaging (MRI) in bladder cancer: relations with recurrence/progression risk

PubMed Central

Kikuchi, Ken; Shigihara, Takeshi; Hashimoto, Yuko; Miyajima, Masayuki; Haga, Nobuhiro; Kojima, Yoshiyuki; Shishido, Fumio

2017-01-01

Abstract AIMS: To evaluate the relationship between the apparent diffusion coefficient (ADC) value for bladder cancer and the recurrence/progression risk of post-transurethral resection (TUR). METHODS: Forty-one patients with initial and non-muscle-invasive bladder cancer underwent MRI from 2009 to 2012. Two radiologists measured ADC values. A pathologist calculated the recurrence/progression scores, and risk was classified based on the scores. Pearson’s correlation was used to analyze the correlations of ADC value with each score and with each risk group, and the optimal cut-off value was established based on receiver operating characteristic (ROC) curve analysis. Furthermore, the relationship between actual recurrence / progression of cases and ADC values was examined by Unpaird U test. RESULTS: There were significant correlations between ADC value and the recurrence score as well as the progression score (P<0.01, P<0.01, respectively). There were also significant correlations between ADC value and the recurrence risk group as well as progression risk group (P=0.042, P<0.01, respectively). The ADC cut-off value on ROC analysis was 1.365 (sensitivity 100%; specificity 97.4%) for the low and intermediate recurrence risk groups, 1.024 (sensitivity 47.4%; specificity 100%) for the intermediate and high recurrence risk groups, 1.252 (sensitivity 83.3%; specificity 81.3%) for the low and intermediate progression risk groups, and 0.955 (sensitivity 87.5%; specificity 63.2%) between the intermediate and high progression risk groups. The difference between the ADC values of the recurrence and nonrecurrence group in Unpaired t test was significant (P<0.05). CONCLUSION: ADC on MRI in bladder cancer could potentially be useful, non-invasive measurement for estimating the risks of recurrence and progression. PMID:28680010

Individualised risk assessment for diabetic retinopathy and optimisation of screening intervals: a scientific approach to reducing healthcare costs.

PubMed

Lund, S H; Aspelund, T; Kirby, P; Russell, G; Einarsson, S; Palsson, O; Stefánsson, E

2016-05-01

To validate a mathematical algorithm that calculates risk of diabetic retinopathy progression in a diabetic population with UK staging (R0-3; M1) of diabetic retinopathy. To establish the utility of the algorithm to reduce screening frequency in this cohort, while maintaining safety standards. The cohort of 9690 diabetic individuals in England, followed for 2 years. The algorithms calculated individual risk for development of preproliferative retinopathy (R2), active proliferative retinopathy (R3A) and diabetic maculopathy (M1) based on clinical data. Screening intervals were determined such that the increase in risk of developing certain stages of retinopathy between screenings was the same for all patients and identical to mean risk in fixed annual screening. Receiver operating characteristic curves were drawn and area under the curve calculated to estimate the prediction capability. The algorithm predicts the occurrence of the given diabetic retinopathy stages with area under the curve =80% for patients with type II diabetes (CI 0.78 to 0.81). Of the cohort 64% is at less than 5% risk of progression to R2, R3A or M1 within 2 years. By applying a 2 year ceiling to the screening interval, patients with type II diabetes are screened on average every 20 months, which is a 40% reduction in frequency compared with annual screening. The algorithm reliably identifies patients at high risk of developing advanced stages of diabetic retinopathy, including preproliferative R2, active proliferative R3A and maculopathy M1. Majority of patients have less than 5% risk of progression between stages within a year and a small high-risk group is identified. Screening visit frequency and presumably costs in a diabetic retinopathy screening system can be reduced by 40% by using a 2 year ceiling. Individualised risk assessment with 2 year ceiling on screening intervals may be a pragmatic next step in diabetic retinopathy screening in UK, in that safety is maximised and cost reduced by about 40%. 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/

Sex differences in the development of perceived family cohesion and depressive symptoms in Taiwanese adolescents.

PubMed

Sze, Tat-Ming; Hsieh, Pei-Jung; Lin, Sieh-Hwa; Chen, I-Jung

2013-08-01

This study investigates the progression of family cohesion perceptions and depressive symptoms during the character development stage in adolescents. Data were used from the Taiwan Youth Project. The final sample comprised 2,690 adolescents with 1,312 girls (48.8%; M age = 13.0 yr., SD = 0.5). Latent curve growth analysis was employed to explore these developments. Seventh-grade girls reported greater family cohesion and more depressive symptoms than boys, and boys reported greater growth in family cohesion than girls. However, progression of depressive symptoms was not associated with the child's sex. Higher perceived family cohesion in Grade 7 correlated with less increase of depressive symptoms from Grades 9 to 11. The long-term positive influence of family cohesion on depressive symptoms is discussed.

Postbuckling and Growth of Delaminations in Composite Plates Subjected to Axial Compression

NASA Technical Reports Server (NTRS)

Reeder, James R.; Chunchu, Prasad B.; Song, Kyongchan; Ambur, Damodar R.

2002-01-01

The postbuckling response and growth of circular delaminations in flat and curved plates are investigated as part of a study to identify the criticality of delamination locations through the laminate thickness. The experimental results from tests on delaminated plates are compared with finite element analysis results generated using shell models. The analytical prediction of delamination growth is obtained by assessing the strain energy release rate results from the finite element model and comparing them to a mixed-mode fracture toughness failure criterion. The analytical results for onset of delamination growth compare well with experimental results generated using a 3-dimensional displacement visualization system. The record of delamination progression measured in this study has resulted in a fully 3-dimensional test case with which progressive failure models can be validated.

Applying Dataflow Architecture and Visualization Tools to In Vitro Pharmacology Data Automation.

PubMed

Pechter, David; Xu, Serena; Kurtz, Marc; Williams, Steven; Sonatore, Lisa; Villafania, Artjohn; Agrawal, Sony

2016-12-01

The pace and complexity of modern drug discovery places ever-increasing demands on scientists for data analysis and interpretation. Data flow programming and modern visualization tools address these demands directly. Three different requirements-one for allosteric modulator analysis, one for a specialized clotting analysis, and one for enzyme global progress curve analysis-are reviewed, and their execution in a combined data flow/visualization environment is outlined. © 2016 Society for Laboratory Automation and Screening.

Improved Polyurethane Storage Tank Performance

DTIC Science & Technology

2014-06-30

condition occurred if water overflowed from the tank vent prior to reaching 45 gallons. A spline curve was drawn around the perimeter of each image so...estimated footprint and height envelope was added for spatial reference. A spline color code key was developed, so that the progression of the tanks...Table 4.5.3). A standard flat plate platen was used for the double butt seams and some closing seams by one fabricator. The other utilized a “Slinky

Efficacy of alkyl dimethyl benzyl ammonium chloride on suppression of Physalospora vaccinii in laboratory assays.

PubMed

Tubajika, K M

2006-10-01

Growth of Physalospora vaccinii on inoculated agar growth medium and cranberries treated with 0.1, 1, 10, 100, and 1,000 ppm of alkyl dimethyl benzyl ammonium chloride (ADBAC) was investigated in the laboratory. In vitro growth assays, the colony diameter, and mycelial dry weight of P. vaccinii was reduced at 1,000 ppm ADBAC. Mild or no reduction of fungal growth and mycelial dry weight was observed at concentrations less than 100 ppm when compared with the nonamended control. Growth of P. vaccinii on inoculated cranberries was inhibited by treatment with 10 and 100 ppm ADBAC. Complete inhibition of fungus growth was also achieved at 1,000 ppm ADBAC. Area under the disease progress curve values in wounded fruits were 75, 77, and 100% at 10, 100, and 1,000 ppm ADBAC, respectively, whereas area under the disease progress curve values in fruits immersed in ADBAC and pathogen were reduced 47 to 100% compared with the untreated fruits used as controls. No P. vaccinii or other fungi were detected on the control fruits inoculated with sterile distilled water. This is the first report on the use of ADBAC to control a field and storage rotting fungus, P. vaccinii. ADBAC is likely to be an important component to any integrated approach for reducing the risks associated with the presence of pathogenic microorganisms in or on foods.

Sphenoid dysplasia in neurofibromatosis type 1: a new technique for repair.

PubMed

Concezio, Di Rocco; Amir, Samii; Gianpiero, Tamburrini; Luca, Massimi; Mario, Giordano

2017-06-01

Sphenoid bone dysplasia in neurofibromatosis type 1 is characterized by progressive exophthalmos and facial disfiguration secondary to herniation of meningeal and cerebral structures. We describe a technique for reconstruction of the sphenoid defect apt at preventing or correcting the ocular globe dislocation. After placement of spinal cerebrospinal fluid drainage to reduce intracranial pressure, the temporal pole is posteriorly dislocated extradurally. The greater sphenoid wing defect is identified. A titanium mesh covered by lyophilized dura, modeled in a curved fashion, is interposed between the bone defect and the cerebro-meningeal structures with its convex surface over the retracted temporal pole. The particular configuration of the titanium mesh allows a self-maintaining position due to the pressure exerted by the brain over its convex central part with its lateral margins consequently pushed and self-anchored against the medial and lateral walls of the temporal fossa. Screw fixation is not needed. The technique utilized in four cases proved to be reliable at the long-term clinical and neuroradiological controls (6 to 19 years). Sphenoid bone dysplasia in NF1, resulting in proptosis and exophthalmos, is usually progressive. It can be surgically repaired using a curved titanium mesh with the convexity faced to the temporal pole that is in the opposite fashion from all the techniques previously introduced. When utilized early in life, the technique can prevent the occurrence of the orbital and facial disfiguration.

Kinetic mechanism of Escherichia coli isocitrate dehydrogenase and its inhibition by glyoxylate and oxaloacetate.

PubMed Central

Nimmo, H G

1986-01-01

The inhibition of Escherichia coli isocitrate dehydrogenase by glyoxylate and oxaloacetate was examined. The shapes of the progress curves in the presence of the inhibitors depended on the order of addition of the assay components. When isocitrate dehydrogenase or NADP+ was added last, the rate slowly decreased until a new, inhibited, steady state was obtained. When isocitrate was added last, the initial rate was almost zero, but the rate increased slowly until the same steady-state value was obtained. Glyoxylate and oxaloacetate gave competitive inhibition against isocitrate and uncompetitive inhibition against NADP+. Product-inhibition studies showed that isocitrate dehydrogenase obeys a compulsory-order mechanism, with coenzyme binding first. Glyoxylate and oxaloacetate bind to and dissociate from isocitrate dehydrogenase slowly. These observations can account for the shapes of the progress curves observed in the presence of the inhibitors. Condensation of glyoxylate and oxaloacetate produced an extremely potent inhibitor of isocitrate dehydrogenase. Analysis of the reaction by h.p.l.c. showed that this correlated with the formation of oxalomalate. This compound decomposed spontaneously in assay mixtures, giving 4-hydroxy-2-oxoglutarate, which was a much less potent inhibitor of the enzyme. Oxalomalate inhibited isocitrate dehydrogenase competitively with respect to isocitrate and was a very poor substrate for the enzyme. The data suggest that the inhibition of isocitrate dehydrogenase by glyoxylate and oxaloacetate is not physiologically significant. PMID:3521584

Labor patterns in twin gestations

PubMed Central

Leftwich, Heidi K.; Zaki, Mary N.; Wilkins, Isabelle; Hibbard, Judith U.

2014-01-01

Objective To compare labor progression in twin vs singleton gestations. Study Design Retrospective review of electronic database created by Consortium on Safe Labor, reflecting labor and delivery information from 12 clinical centers 2002-2008. Women with twin gestations, cephalic presentation of presenting twin, gestational age ≥34 weeks, with ≥2 cervical examinations were included. Exclusion criteria were fetal anomalies or demise. Singleton controls were selected by the same criteria. Categorical variables were analyzed by χ2; continuous by Student t test. Interval censored regression was used to determine distribution for time of cervical dilation in centimeters, or “traverse times,” and controlled for confounding factors. Repeated-measures analysis constructed mean labor curves by parity and number of fetuses. Results A total of 891 twin gestations were compared with 100,513 singleton controls. Twin gestations were more often older, white or African American, earlier gestational age, increased prepregnancy body mass index, and with lower birthweight. There was no difference in number of prior cesarean deliveries, induction, or augmentation, or epidural use. Median traverse times increased at every centimeter interval in nulliparous twins, in both unadjusted and adjusted analysis (P < .01). A similar pattern was noted for multiparas in both analyses. Labor curves demonstrated a delayed inflection point in the labor pattern for nulliparous and multiparous twin gestations. Conclusion Both nulliparous and multiparous women have slower progression of active phase labor with twins even when controlling for confounding factors. PMID:23871795

Genetic study of multimodal imaging Alzheimer's disease progression score implicates novel loci.

PubMed

Scelsi, Marzia A; Khan, Raiyan R; Lorenzi, Marco; Christopher, Leigh; Greicius, Michael D; Schott, Jonathan M; Ourselin, Sebastien; Altmann, Andre

2018-05-30

Identifying genetic risk factors underpinning different aspects of Alzheimer's disease has the potential to provide important insights into pathogenesis. Moving away from simple case-control definitions, there is considerable interest in using quantitative endophenotypes, such as those derived from imaging as outcome measures. Previous genome-wide association studies of imaging-derived biomarkers in sporadic late-onset Alzheimer's disease focused only on phenotypes derived from single imaging modalities. In contrast, we computed a novel multi-modal neuroimaging phenotype comprising cortical amyloid burden and bilateral hippocampal volume. Both imaging biomarkers were used as input to a disease progression modelling algorithm, which estimates the biomarkers' long-term evolution curves from population-based longitudinal data. Among other parameters, the algorithm computes the shift in time required to optimally align a subjects' biomarker trajectories with these population curves. This time shift serves as a disease progression score and it was used as a quantitative trait in a discovery genome-wide association study with n = 944 subjects from the Alzheimer's Disease Neuroimaging Initiative database diagnosed as Alzheimer's disease, mild cognitive impairment or healthy at the time of imaging. We identified a genome-wide significant locus implicating LCORL (rs6850306, chromosome 4; P = 1.03 × 10-8). The top variant rs6850306 was found to act as an expression quantitative trait locus for LCORL in brain tissue. The clinical role of rs6850306 in conversion from healthy ageing to mild cognitive impairment or Alzheimer's disease was further validated in an independent cohort comprising healthy, older subjects from the National Alzheimer's Coordinating Center database. Specifically, possession of a minor allele at rs6850306 was protective against conversion from mild cognitive impairment to Alzheimer's disease in the National Alzheimer's Coordinating Center cohort (hazard ratio = 0.593, 95% confidence interval = 0.387-0.907, n = 911, PBonf = 0.032), in keeping with the negative direction of effect reported in the genome-wide association study (βdisease progression score = -0.07 ± 0.01). The implicated locus is linked to genes with known connections to Alzheimer's disease pathophysiology and other neurodegenerative diseases. Using multimodal imaging phenotypes in association studies may assist in unveiling the genetic drivers of the onset and progression of complex diseases.

Time-dependent classification accuracy curve under marker-dependent sampling.

PubMed

Zhu, Zhaoyin; Wang, Xiaofei; Saha-Chaudhuri, Paramita; Kosinski, Andrzej S; George, Stephen L

2016-07-01

Evaluating the classification accuracy of a candidate biomarker signaling the onset of disease or disease status is essential for medical decision making. A good biomarker would accurately identify the patients who are likely to progress or die at a particular time in the future or who are in urgent need for active treatments. To assess the performance of a candidate biomarker, the receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC) are commonly used. In many cases, the standard simple random sampling (SRS) design used for biomarker validation studies is costly and inefficient. In order to improve the efficiency and reduce the cost of biomarker validation, marker-dependent sampling (MDS) may be used. In a MDS design, the selection of patients to assess true survival time is dependent on the result of a biomarker assay. In this article, we introduce a nonparametric estimator for time-dependent AUC under a MDS design. The consistency and the asymptotic normality of the proposed estimator is established. Simulation shows the unbiasedness of the proposed estimator and a significant efficiency gain of the MDS design over the SRS design. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cortisol dysregulation: the bidirectional link between stress, depression, and type 2 diabetes mellitus.

PubMed

Joseph, Joshua J; Golden, Sherita H

2017-03-01

Controversy exists over the role of stress and depression in the pathophysiology of type 2 diabetes mellitus. Depression has been shown to increase the risk for progressive insulin resistance and incident type 2 diabetes mellitus in multiple studies, whereas the association of stress with diabetes is less clear, owing to differences in study designs and in forms and ascertainment of stress. The biological systems involved in adaptation that mediate the link between stress and physiological functions include the hypothalamic-pituitary-adrenal (HPA) axis and the autonomic nervous and immune systems. The HPA axis is a tightly regulated system that represents one of the body's mechanisms for responding to acute and chronic stress. Depression is associated with cross-sectional and longitudinal alterations in the diurnal cortisol curve, including a blunted cortisol awakening response and flattening of the diurnal cortisol curve. Flattening of the diurnal cortisol curve is also associated with insulin resistance and type 2 diabetes mellitus. In this article, we review and summarize the evidence supporting HPA axis dysregulation as an important biological link between stress, depression, and type 2 diabetes mellitus. © 2016 New York Academy of Sciences.

Rethinking one of criminology’s ‘brute facts’: The age–crime curve and the crime drop in Scotland

PubMed Central

Matthews, Ben; Minton, Jon

2017-01-01

Examining annual variation in the age–crime curve as a way to better understand the recent crime drop, this paper explores how the age distribution of convicted offending changed for men and women in Scotland between 1989 and 2011. This analysis employs shaded contour plots as a method of visualizing annual change in the age–crime curve. Similar to recent findings from the USA, we observed falling rates of convicted offending for young people, primarily owing to lower rates of convicted offending for young men. In contrast to the US literature we also find increases in the rate of convicted offending for those in their mid-twenties to mid-forties, which are relatively greater for women than men. Analysis of annual change shows different phases in the progression of these trends, with falls in prevalence during the 1990s reflecting lower rates of convictions for acquisitive crime, but falls between 2007 and 2011 being spread across multiple crime types. Explanations of the crime drop in Scotland and elsewhere must be able to account for different patterns of change across age, sex, crime type and time. PMID:29805319

Cortisol dysregulation: the bidirectional link between stress, depression, and type 2 diabetes mellitus

PubMed Central

Joseph, Joshua J.; Golden, Sherita H.

2016-01-01

Controversy exists over the role of stress and depression in the pathophysiology of type 2 diabetes mellitus. Depression has been shown to increase the risk for progressive insulin resistance and incident type 2 diabetes mellitus in multiple studies, whereas the association of stress with diabetes is less clear, owing to differences in study designs and in forms and ascertainment of stress. The biological systems involved in adaptation that mediate the link between stress and physiological functions include the hypothalamic–pituitary–adrenal axis and the autonomic nervous and immune systems. The hypothalamic–pituitary–adrenal axis is a tightly regulated system that represents one of the body’s mechanisms for responding to acute and chronic stress. Depression is associated with cross-sectional and longitudinal alterations in the diurnal cortisol curve, including a blunted cortisol awakening response and flattening of the diurnal cortisol curve. Flattening of the diurnal cortisol curve is also associated with insulin resistance and type 2 diabetes mellitus. In this article, we review and summarize the evidence supporting hypothalamic–pituitary–adrenal axis dysregulation as an important biological link between stress, depression, and type 2 diabetes mellitus. PMID:27750377

THE ELECTRICAL ACTIVATION OF PASSIVE IRON WIRES IN NITRIC ACID

PubMed Central

Lillie, Ralph S.

1935-01-01

1. The relation between the E. M. F. and the minimal duration of an activating current has been determined for passive iron wires in nitric acid under varying conditions of concentration of acid, duration of recovery period, and presence of surface-action compounds. 2. The characteristic intensity-duration curves resemble those of irritable living tissues with moderate speeds of response to stimulation (with chronaxies of the order of 10 to 30σ). 3. The intensity of the current required for activation, as well as its minimal effective duration for a given intensity, increases rapidly with increase in the concentration of HNO3. 4. The responsiveness of the iron wire to brief currents is low immediately after activation and returns progressively to the original level during the immediately following period, at first rapidly and then slowly, following a time curve resembling the corresponding curve of living tissues during the relative refractory period. 5. Surface-active compounds decrease reversibly, to a degree dependent on concentration, the responsiveness of iron wires to brief currents. 6. Conditions are described under which the iron wire is activated by the break of an already flowing constant current. PMID:19872905

Cell killing mode of liblomycin (NK313), a novel dose-survival relationship different from bleomycins.

PubMed

Kuramochi-Motegi, A; Kuramochi, H; Takahashi, K; Takeuchi, T

1991-04-01

Liblomycin (NK313) is a novel derivative of bleomycin (BLM) and peplomycin (PEP). The cell kill kinetics of NK313 on rat ascites hepatoma AH66 were compared with those of PEP. NK313 induced intracellular DNA cleavage and arrested cell cycle progression at the G2 phase similarly to PEP. The cytocidal effect of NK313, however, was found to be different from that of PEP as described below: 1) The dose-survival curve for cells exposed to PEP for 1 hour was upward concave, whereas in case of NK313, the survival curve was linear. PEP was more effective to AH66 than NK313 at lower concentration, but at higher concentration, NK313 was much more effective. 2) The time-survival curve for cells treated with either NK313 or PEP was biphasic. NK313, however, did not induce temporary resistance of AH66 cells to NK313, while PEP induced resistance to PEP. 3) NK313 was effective against the cells which became temporarily resistant to PEP by the treatment of PEP. These differences suggest that NK313 might be of value to treat PEP-insensitive tumor cells.

DSC, X-ray and FTIR studies of a gemfibrozil/dimethyl-β-cyclodextrin inclusion complex produced by co-grinding.

PubMed

Aigner, Z; Berkesi, O; Farkas, G; Szabó-Révész, P

2012-01-05

The steps of formation of an inclusion complex produced by the co-grinding of gemfibrozil and dimethyl-β-cyclodextrin were investigated by differential scanning calorimetry (DSC), X-ray powder diffractometry (XRPD) and Fourier transform infrared (FTIR) spectroscopy with curve-fitting analysis. The endothermic peak at 59.25°C reflecting the melting of gemfibrozil progressively disappeared from the DSC curves of the products on increase of the duration of co-grinding. The crystallinity of the samples too gradually decreased, and after 35min of co-grinding the product was totally amorphous. Up to this co-grinding time, XRPD and FTIR investigations indicated a linear correlation between the cyclodextrin complexation and the co-grinding time. After co-grinding for 30min, the ratio of complex formation did not increase. These studies demonstrated that co-grinding is a suitable method for the complexation of gemfibrozil with dimethyl-β-cyclodextrin. XRPD analysis revealed the amorphous state of the gemfibrozil-dimethyl-β-cyclodextrin product. FTIR spectroscopy with curve-fitting analysis may be useful as a semiquantitative analytical method for discriminating the molecular and amorphous states of gemfibrozil. Copyright © 2011 Elsevier B.V. All rights reserved.

Finding Exoplanets Using Point Spread Function Photometry on Kepler Data

NASA Astrophysics Data System (ADS)

Amaro, Rachael Christina; Scolnic, Daniel; Montet, Ben

2018-01-01

The Kepler Mission has been able to identify over 5,000 exoplanet candidates using mostly aperture photometry. Despite the impressive number of discoveries, a large portion of Kepler’s data set is neglected due to limitations using aperture photometry on faint sources in crowded fields. We present an alternate method that overcomes those restrictions — Point Spread Function (PSF) photometry. This powerful tool, which is already used in supernova astronomy, was used for the first time on Kepler Full Frame Images, rather than just looking at the standard light curves. We present light curves for stars in our data set and demonstrate that PSF photometry can at least get down to the same photometric precision as aperture photometry. As a check for the robustness of this method, we change small variables (stamp size, interpolation amount, and noise correction) and show that the PSF light curves maintain the same repeatability across all combinations for one of our models. We also present our progress in the next steps of this project, including the creation of a PSF model from the data itself and applying the model across the entire data set at once.

Correlation between use time of machine and decline curve for emerging enterprise information systems

NASA Astrophysics Data System (ADS)

Chang, Yao-Chung; Lai, Chin-Feng; Chuang, Chi-Cheng; Hou, Cheng-Yu

2018-04-01

With the progress of science and technology, more and more machines are adpot to help human life better and more convenient. When the machines have been used for a longer period of time so that the machine components are getting old, the amount of power comsumption will increase and easily cause the machine to overheat. This also causes a waste of invisible resources. If the Internet of Everything (IoE) technologies are able to be applied into the enterprise information systems for monitoring the machines use time, it can not only make energy can be effectively used, but aslo create a safer living environment. To solve the above problem, the correlation predict model is established to collect the data of power consumption converted into power eigenvalues. This study takes the power eigenvalue as the independent variable and use time as the dependent variable in order to establish the decline curve. Ultimately, the scoring and estimation modules are employed to seek the best power eigenvalue as the independent variable. To predict use time, the correlation is discussed between the use time and the decline curve to improve the entire behavioural analysis of the facilitate recognition of the use time of machines.

Combining freeform optics and curved detectors for wide field imaging: a polynomial approach over squared aperture.

PubMed

Muslimov, Eduard; Hugot, Emmanuel; Jahn, Wilfried; Vives, Sebastien; Ferrari, Marc; Chambion, Bertrand; Henry, David; Gaschet, Christophe

2017-06-26

In the recent years a significant progress was achieved in the field of design and fabrication of optical systems based on freeform optical surfaces. They provide a possibility to build fast, wide-angle and high-resolution systems, which are very compact and free of obscuration. However, the field of freeform surfaces design techniques still remains underexplored. In the present paper we use the mathematical apparatus of orthogonal polynomials defined over a square aperture, which was developed before for the tasks of wavefront reconstruction, to describe shape of a mirror surface. Two cases, namely Legendre polynomials and generalization of the Zernike polynomials on a square, are considered. The potential advantages of these polynomials sets are demonstrated on example of a three-mirror unobscured telescope with F/# = 2.5 and FoV = 7.2x7.2°. In addition, we discuss possibility of use of curved detectors in such a design.

Optimal algorithm for automatic detection of microaneurysms based on receiver operating characteristic curve

NASA Astrophysics Data System (ADS)

Xu, Lili; Luo, Shuqian

2010-11-01

Microaneurysms (MAs) are the first manifestations of the diabetic retinopathy (DR) as well as an indicator for its progression. Their automatic detection plays a key role for both mass screening and monitoring and is therefore in the core of any system for computer-assisted diagnosis of DR. The algorithm basically comprises the following stages: candidate detection aiming at extracting the patterns possibly corresponding to MAs based on mathematical morphological black top hat, feature extraction to characterize these candidates, and classification based on support vector machine (SVM), to validate MAs. Feature vector and kernel function of SVM selection is very important to the algorithm. We use the receiver operating characteristic (ROC) curve to evaluate the distinguishing performance of different feature vectors and different kernel functions of SVM. The ROC analysis indicates the quadratic polynomial SVM with a combination of features as the input shows the best discriminating performance.

Optimal algorithm for automatic detection of microaneurysms based on receiver operating characteristic curve.

PubMed

Xu, Lili; Luo, Shuqian

2010-01-01

Microaneurysms (MAs) are the first manifestations of the diabetic retinopathy (DR) as well as an indicator for its progression. Their automatic detection plays a key role for both mass screening and monitoring and is therefore in the core of any system for computer-assisted diagnosis of DR. The algorithm basically comprises the following stages: candidate detection aiming at extracting the patterns possibly corresponding to MAs based on mathematical morphological black top hat, feature extraction to characterize these candidates, and classification based on support vector machine (SVM), to validate MAs. Feature vector and kernel function of SVM selection is very important to the algorithm. We use the receiver operating characteristic (ROC) curve to evaluate the distinguishing performance of different feature vectors and different kernel functions of SVM. The ROC analysis indicates the quadratic polynomial SVM with a combination of features as the input shows the best discriminating performance.

Correlation of in vitro time-kill curves and kinetics of bacterial killing in cerebrospinal fluid during ceftriaxone therapy of experimental Escherichia coli meningitis.

PubMed Central

Decazes, J M; Ernst, J D; Sande, M A

1983-01-01

Ceftriaxone was highly active in eliminating Escherichia coli from the cerebrospinal fluid of rabbits infected with experimental meningitis. However, concentrations equal to or greater than 10 times the minimal bactericidal concentration had to be achieved to ensure optimal efficacy (rate of kill, 1.5 log10 CFU/ml per h). In contrast to other beta-lactams studied in this model, ceftriaxone concentrations in cerebrospinal fluid progressively increased, whereas serum steady state was obtained by constant infusion. The percent penetration was 2.1% after 1 h of therapy, in contrast to 8.9% after 7 h (P less than 0.001). In vitro time-kill curves done in cerebrospinal fluid or broth more closely predicted the drug concentrations required for a maximum cidal effect in vivo than that predicted by determinations of minimal inhibitory or bactericidal concentrations. PMID:6316841

[Adolescent idiopathic scoliosis].

PubMed

2016-12-01

Adolescent idiopathic scoliosis is a 3D spinal deformity in frontal, sagittal and axial planes, with high relevance in the pediatric population especially in adolescents and females between 10 years of age and the end of growth spurt and skeletal maturity. The radiographic manifestation is a curve greater than 10° measured by Cobb method associated with vertebral rotation. "Idiopathic" diagnosis has to be done after neuroanatomical anomalies of the posterior cerebral fosa and spinal canal have been ruled out. The physical finding of a thoracic or lumbar hump is the clinical manifestation of vertebral rotation seen in a forward bending test (Adam's Test). It is recommended that all curves with a magnitude greater than 20° have to be controlled and treated by a spinal surgeon being observation, bracing and surgery the different treatment options based on the extent, progression of deformity and basically the clinical condition of the patient. Sociedad Argentina de Pediatría.

Efficacy of nighttime brace in preventing progression of idiopathic scoliosis of less than 25°.

PubMed

Lateur, G; Grobost, P; Gerbelot, J; Eid, A; Griffet, J; Courvoisier, A

2017-04-01

The objective of the present study was to assess, at skeletal maturity, the efficacy of non-operative treatment by isolated nighttime brace in the prevention of progression of progressive idiopathic scoliosis of less than 25°. Isolated nighttime brace treatment is effective in the prevention of progression of mild progressive idiopathic scoliosis (Cobb<25°). A single-center retrospective study included 142 patients managed by nighttime brace for progressive idiopathic scoliosis with Cobb angle<25°, with assessment at skeletal maturity. Mean Cobb angle at start of treatment was 15.5° (range, 10-25°). Mean values for Cobb angle and sagittal parameters before treatment and at skeletal maturity were compared on Student t-test. Change in Cobb angle over time was also analyzed. Mean Cobb angle at skeletal maturity was 16.3°, showing significant increase over baseline (15.5°; P=0.04), although the difference was less than the uncertainty of measurement (±6°). In baseline Risser 0 or 1, mean change in Cobb angle at skeletal maturity (16.2°) was not significant (P=0.1). Cobb angle diminished in 26 cases (18%), increased in 24 (17%) and was unchanged in 92 (65%). The present study confirmed the efficacy of non-operative treatment by nighttime brace in mild progressive idiopathic scoliosis (<25°) in a large majority of cases. A nighttime brace thus seems to be an effective option for the treatment of adolescent scoliosis, ensuring a safe curve of around 20°. Level IV, retrospective study. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Environmental standards for ionizing radiation: theoretical basis for dose-response curves.

PubMed Central

Upton, A C

1983-01-01

The types of injury attributable to ionizing radiation are subdivided, for purposes of risk assessment and radiological protection, into two broad categories: stochastic effects and nonstochastic effects. Stochastic effects are viewed as probablistic phenomena, varying in frequency but not severity as a function of the dose, without any threshold; nonstochastic effects are viewed as deterministic phenomena, varying in both frequency and severity as a function of the dose, with clinical thresholds. Included among stochastic effects are heritable effects (mutations and chromosome aberrations) and carcinogenic effects. Both types of effects are envisioned as unicellular phenomena which can result from nonlethal injury of individual cells, without the necessity of damage to other cells. For the induction of mutations and chromosome aberrations in the low-to-intermediate dose range, the dose-response curve with high-linear energy transfer (LET) radiation generally conforms to a linear nonthreshold relationship and varies relatively little with the dose rate. In contrast, the curve with low-LET radiation generally conforms to a linear-quadratic relationship, rising less steeply than the curve with high-LET radiation and increasing in slope with increasing dose and dose rate. The dose-response curve for carcinogenic effects varies widely from one type of neoplasm to another in the intermediate-to-high dose range, in part because of differences in the way large doses of radiation can affect the promotion and progression of different neoplasms. Information about dose-response relations for low-level irradiation is fragmentary but consistent, in general, with the hypothesis that the neoplastic transformation may result from mutation, chromosome aberration or genetic recombination in a single susceptible cell. PMID:6653536

The TGFB1 gene is associated with curve severity but not with the development of adolescent idiopathic scoliosis: a replication study in the Chinese population.

PubMed

Xu, Leilei; Sun, Weixiang; Qin, Xiaodong; Qiu, Yong; Zhu, Zezhang

2016-01-13

The transforming growth factor beta-1 (TGFB1) gene was recently reported to be a new susceptible gene of adolescent idiopathic scoliosis (AIS) in Russian population. This study aimed to replicate the relationship between the TGFB1 gene and the susceptibility of AIS in a Chinese population, and to further describe its association with the curve severity. A total of 1251 female AIS patients and 994 age-matched healthy controls were included in this study. The rs1800469 of TGFB1 gene was genotyped for all participants using the PCR-based Invader assay. The differences of genotype and allele distributions between AIS patients and healthy controls were assessed using the Chi-square test. One-way ANOVA test was used to compare the mean Cobb angles among patients with different genotypes. There was no significant difference in terms of the genotype and the allele frequency between the patients and the controls. The mean Cobb angle was 34.7 ± 11.9° (range 25-61°). Case-only analysis showed that rs1800469 was significantly associated with the curve severity. Patients with genotype TT had remarkably higher curve magnitude (39.1 ± 12.8°) than those with genotype CT (34.8 ± 11.1°) or CC (32.1 ± 10.6°). The TGFB1 gene may not be a predisposition gene of AIS in the Chinese population. However, it can play a role in the curve progression of AIS. Replication studies in other ethnic groups are warranted to understand the implication of TGFB1 gene in AIS.

Idiopathic Early-Onset Scoliosis: Growing Rods Versus Vertically Expandable Prosthetic Titanium Ribs at 5-Year Follow-up.

PubMed

Bachabi, Malick; McClung, Anna; Pawelek, Jeff B; El Hawary, Ron; Thompson, George H; Smith, John T; Vitale, Michael G; Akbarnia, Behrooz A; Sponseller, Paul D

2018-06-08

Distraction-based techniques allow spinal growth until skeletal maturity while preventing curve progression. Two multicenter early-onset scoliosis databases were used to identify patients with idiopathic spine abnormalities treated with traditional growing rods (TGR) or vertically expandable titanium ribs (VEPTR). Patients underwent at least 4 lengthenings and had at least 5-year follow-up. Significance was set at P<0.05. In total, 50 patients treated with TGR and 22 treated with VEPTR were included. Mean (±SD) age at surgery was 5.5 (±2.0) years for the TGR group versus 4.3 (±1.9) years for the VEPTR group (P=0.044); other demographic parameters were similar. VEPTR patients had more procedures (mean 15±4.2) than TGR patients (mean 10±4.0) (P=0.001). Unilateral constructs were present in 18% (4 of 22) of VEPTR and 16% (8 of 50) of TGR patients. Bilateral constructs spanned a mean 2.1 additional surgical levels and exposed patients to 1.6 fewer procedures than unilateral constructs. Curve correction was similar between bilateral and unilateral constructs. TGR patients experienced greater curve correction (50%) than VEPTR patients (27%) (P<0.001) and achieved a greater percentage of thoracic height gain (24%) than VEPTR patients (12%) (P=0.024). At latest follow-up, TGR patients had better maintenance of curve correction, less kyphosis, and 15% greater absolute gain in thoracic height versus VEPTR patients. TGR patients had a lower rate of wound complications (14%) than VEPTR patients (41%) (P=0.011). In patients with idiopathic early-onset scoliosis, TGRs produced greater initial curve correction, greater thoracic height gains, less kyphosis, and lower incidence of wound complications compared with VEPTR. Level III.

Bracing can reduce high degree curves and improve aesthetics immediately after the end of growth. Final results of a retrospective case series.

PubMed

Negrini, Stefano; Donzelli, Sabrina; Lusini, Monia; Zaina, Fabio

2012-01-01

Recently it has been shown that idiopathic scoliosis (IS) curves can be reduced with bracing, and it has been proposed that this could be useful in non-surgically treated high degree curves even after Risser 3. Moreover, bracing has been shown to be able to improve aesthetics, and this could be another reason to treat some patients with cosmetic needs. Our aim is to preliminary check if results can be obtained in IS patients after Risser 3. Design. Retrospective uncontrolled cohort study. Inclusion criteria. All IS patients treated on a voluntary basis for aesthetic reasons and/or for curve reduction; Risser 4-5 at start; end of treatment reached. Population. 34 females and 2 males, age 16.2±1.6 years, Cobb angle 27.6°±8.9°. Treatment. Lyon or SPoRT braces 18 to 24 hours/day, specific SEAS exercises, rapid weaning (2-3 hours every 6 months). Outcome criteria: SRS (unchanged; worsened over 6°; over 45° at the end of treatment; surgically treated), radiographic and clinical. Statistics. ANOVA and chi-test. The reported compliance during the 2.8 ± 1.1 treatment years was 95.1%, while residual growth was 0.9 ± 1.1 cm. Improvements were found in 39% of this cohort, (46% in curves over 30°). Only 1 patient progressed 6°. We found highly statistically significant reductions of maximal (-4.4°), thoracic (-6.0°) and thoracolumbar (-6.6°) curves. Statistically significant improvements were found for Aesthetic Index. Before 20 years of age, even in skeletally mature patients, it is possible to reach radiographic and aesthetic improvements, although not as good as during growth. Correction is based on bone growth, but ligaments and neuromuscular control of posture can also be involved.

Radiation and annealing response of WWER 440 beltline welding seams

NASA Astrophysics Data System (ADS)

Viehrig, Hans-Werner; Houska, Mario; Altstadt, Eberhard

2015-01-01

The focus of this paper is on the irradiation response and the effect of thermal annealing in weld materials extracted from decommissioned WWER 440 reactor pressure vessels of the nuclear power plant Greifswald. The characterisation is based on the measurement of the hardness, the yield stress, the Master Curve reference temperature, T0, and the Charpy-V transition temperature through the thickness of multi-layer beltline welding seams in the irradiated and the thermally annealed condition. Additionally, the weld bead structure was characterised by light microscopic studies. We observed a large variation in the through thickness T0 values in the irradiated as well as in thermally annealed condition. The T0 values measured with the T-S-oriented Charpy size SE(B) specimens cut from different thickness locations of the multilayer welding seams strongly depend on the intrinsic weld bead structure along the crack tip. The Master Curve, T0, and Charpy-V, TT47J, based ductile-to-brittle transition temperature progressions through the thickness of the multi-layer welding seam do not correspond to the forecast according to the Russian code. In general, the fracture toughness values at cleavage failure, KJc, measured on SE(B) specimens from the irradiated and large-scale thermally annealed beltline welding seams follow the Master Curve description, but more than the expected number lie outside the curves for 2% and 98% fracture probability. In this case the test standard ASTM E1921 indicates the investigated multi-layer weld metal as not uniform. The multi modal Master Curve based approach describes the temperature dependence of the specimen size adjusted KJc-1T values well. Thermal annealing at 475 °C for 152 h results in the expected decrease of the hardness and tensile strength and the shift of Master Curve and Charpy-V based ductile-to-brittle transition temperatures to lower values.

Renal Parenchymal Area Growth Curves for Children 0 to 10 Months Old.

PubMed

Fischer, Katherine; Li, Chunming; Wang, Huixuan; Song, Yihua; Furth, Susan; Tasian, Gregory E

2016-04-01

Low renal parenchymal area, which is the gross area of the kidney in maximal longitudinal length minus the area of the collecting system, has been associated with increased risk of end stage renal disease during childhood in boys with posterior urethral valves. To our knowledge normal values do not exist. We aimed to increase the clinical usefulness of this measure by defining normal renal parenchymal area during infancy. In a cross-sectional study of children with prenatally detected mild unilateral hydronephrosis who were evaluated between 2000 and 2012 we measured the renal parenchymal area of normal kidney(s) opposite the kidney with mild hydronephrosis. Measurement was done with ultrasound from birth to post-gestational age 10 months. We used the LMS method to construct unilateral, bilateral, side and gender stratified normalized centile curves. We determined the z-score and the centile of a total renal parenchymal area of 12.4 cm(2) at post-gestational age 1 to 2 weeks, which has been associated with an increased risk of kidney failure before age 18 years in boys with posterior urethral valves. A total of 975 normal kidneys of children 0 to 10 months old were used to create renal parenchymal area centile curves. At the 97th centile for unilateral and single stratified curves the estimated margin of error was 4.4% to 8.8%. For bilateral and double stratified curves the estimated margin of error at the 97th centile was 6.6% to 13.2%. Total renal parenchymal area less than 12.4 cm(2) at post-gestational age 1 to 2 weeks had a z-score of -1.96 and fell at the 3rd percentile. These normal renal parenchymal area curves may be used to track kidney growth in infants and identify those at risk for chronic kidney disease progression. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Prospects for reconciling the conflict between economic growth and biodiversity conservation with technological progress.

PubMed

Czech, Brian

2008-12-01

The conflict between economic growth and biodiversity conservation is understood in portions of academia and sometimes acknowledged in political circles. Nevertheless, there is not a unified response. In political and policy circles, the environmental Kuznets curve (EKC) is posited to solve the conflict between economic growth and environmental protection. In academia, however, the EKC has been deemed fallacious in macroeconomic scenarios and largely irrelevant to biodiversity. A more compelling response to the conflict is that it may be resolved with technological progress. Herein I review the conflict between economic growth and biodiversity conservation in the absence of technological progress, explore the prospects for technological progress to reconcile that conflict, and provide linguistic suggestions for describing the relationships among economic growth, technological progress, and biodiversity conservation. The conflict between economic growth and biodiversity conservation is based on the first two laws of thermodynamics and principles of ecology such as trophic levels and competitive exclusion. In this biophysical context, the human economy grows at the competitive exclusion of nonhuman species in the aggregate. Reconciling the conflict via technological progress has not occurred and is infeasible because of the tight linkage between technological progress and economic growth at current levels of technology. Surplus production in existing economic sectors is required for conducting the research and development necessary for bringing new technologies to market. Technological regimes also reflect macroeconomic goals, and if the goal is economic growth, reconciliatory technologies are less likely to be developed. As the economy grows, the loss of biodiversity may be partly mitigated with end-use innovation that increases technical efficiency, but this type of technological progress requires policies that are unlikely if the conflict between economic growth and biodiversity conservation (and other aspects of environmental protection) is not acknowledged.

Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section.

PubMed

Bulusu, Kartik V; Plesniak, Michael W

2016-07-19

The arterial network in the human vasculature comprises of ubiquitously present blood vessels with complex geometries (branches, curvatures and tortuosity). Secondary flow structures are vortical flow patterns that occur in curved arteries due to the combined action of centrifugal forces, adverse pressure gradients and inflow characteristics. Such flow morphologies are greatly affected by pulsatility and multiple harmonics of physiological inflow conditions and vary greatly in size-strength-shape characteristics compared to non-physiological (steady and oscillatory) flows (1 - 7). Secondary flow structures may ultimately influence the wall shear stress and exposure time of blood-borne particles toward progression of atherosclerosis, restenosis, sensitization of platelets and thrombosis (4 - 6, 8 - 13). Therefore, the ability to detect and characterize these structures under laboratory-controlled conditions is precursor to further clinical investigations. A common surgical treatment to atherosclerosis is stent implantation, to open up stenosed arteries for unobstructed blood flow. But the concomitant flow perturbations due to stent installations result in multi-scale secondary flow morphologies (4 - 6). Progressively higher order complexities such as asymmetry and loss in coherence can be induced by ensuing stent failures vis-à-vis those under unperturbed flows (5). These stent failures have been classified as "Types I-to-IV" based on failure considerations and clinical severity (14). This study presents a protocol for the experimental investigation of the complex secondary flow structures due to complete transverse stent fracture and linear displacement of fractured parts ("Type IV") in a curved artery model. The experimental method involves the implementation of particle image velocimetry (2C-2D PIV) techniques with an archetypal carotid artery inflow waveform, a refractive index matched blood-analog working fluid for phase-averaged measurements (15 - 18). Quantitative identification of secondary flow structures was achieved using concepts of flow physics, critical point theory and a novel wavelet transform algorithm applied to experimental PIV data (5, 6, 19 - 26).

Selection of an early biomarker for vascular normalization using dynamic contrast-enhanced ultrasonography to predict outcomes of metastatic patients treated with bevacizumab.

PubMed

Lassau, N; Coiffier, B; Kind, M; Vilgrain, V; Lacroix, J; Cuinet, M; Taieb, S; Aziza, R; Sarran, A; Labbe-Devilliers, C; Gallix, B; Lucidarme, O; Ptak, Y; Rocher, L; Caquot, L M; Chagnon, S; Marion, D; Luciani, A; Feutray, S; Uzan-Augui, J; Benatsou, B; Bonastre, J; Koscielny, S

2016-10-01

Dynamic contrast-enhanced ultrasonography (DCE-US) has been used for evaluation of tumor response to antiangiogenic treatments. The objective of this study was to assess the link between DCE-US data obtained during the first week of treatment and subsequent tumor progression. Patients treated with antiangiogenic therapies were included in a multicentric prospective study from 2007 to 2010. DCE-US examinations were available at baseline and at day 7. For each examination, a 3 min perfusion curve was recorded just after injection of a contrast agent. Each perfusion curve was modeled with seven parameters. We analyzed the correlation between criteria measured up to day 7 on freedom from progression (FFP). The impact was assessed globally, according to tumor localization and to type of treatment. The median follow-up was 20 months. The mean transit time (MTT) evaluated at day 7 was the only criterion significantly associated with FFP (P = 0.002). The cut-off point maximizing the difference between FFP curves was 12 s. Patients with at least a 12 s MTT had a better FFP. The results according to tumor type were significantly heterogeneous: the impact of MTT on FFP was more marked for breast cancer (P = 0.004) and for colon cancer (P = 0.025) than for other tumor types. Similarly, the differences in FFP according to MTT at day 7 were marked (P = 0.004) in patients receiving bevacizumab. The MTT evaluated with DCE-US at day 7 is significantly correlated to FFP of patients treated with bevacizumab. This criterion might be linked to vascular normalization. 2007-A00399-44. © The Author 2016. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Day-night fluctuation of pulse oximetry: an exploratory study in pediatric inpatients.

PubMed

Vargas, Mario H; Heyaime-Lalane, Jorge; Pérez-Rodríguez, Liliana; Zúñiga-Vázquez, Guillermo; Furuya, María Elena Y

2008-01-01

Pulse oximetry is a simple and non-invasive procedure widely used nowadays in the clinical practice. However, it is unclear if SpO2 values are constant throughout the 24 hours of the day or have periodic fluctuations. In the present study we evaluated if progressive day-night variations of SpO, values occur in children. Pulse oximetry (Nonin 2500) was carried out approximately every 2 hours during a 24-hours period in pediatric patients hospitalized due to different diseases but without acute or chronic respiratory diseases. Measurements were analyzed through the cosinor method (sinusoidal curve fitting). A total of 131 patients (23 days to 16 years old) were studied. A sinusoidal fitting of the SpO2 values was accomplished in 84.7% of children. According to these curves, maximal SpO2 values occurred in the late afternoon [4:53 PM (3:49-5:32 PM), median (quartile 1-quartile 3)], while minimal values appeared in the first hours of the day [3:06 AM (2:12-4:08 AM)]. This pattern was the same in sleeping or awake children. More than half of these sinusoidal curves had a period near to 24 hours (between 20 and 28 hours). An additional finding was that maximal and minimal SpO2 values diminished with age (approximately 0.15 and approximately 0.13% SpO2 per year, respectively). In children less than six years old 5th percentile of SpO2 values were 93.8% in the late afternoon and 89.8% in the early hours of the day, while corresponding figures for older children were 91.0% and 88.5%, respectively. Our results suggested that, regardless of the sleep influence, in most children the SpO2 follows a progressive fluctuation during a 24-hours cycle, a pattern which is suggestive of a circadian rhythm. A prospective study in healthy children is warranted.

Training With Curved Laparoscopic Instruments in Single-Port Setting Improves Performance Using Straight Instruments: A Prospective Randomized Simulation Study.

PubMed

Lukovich, Peter; Sionov, Valery Ben; Kakucs, Timea

2016-01-01

Lately single-port surgery is becoming a widespread procedure, but it is more difficult than conventional laparoscopy owing to the lack of triangulation. Although, these operations are also possible with standard laparoscopic instruments, curved instruments are being developed. The aims of the study were to identify the effect of training on a box trainer in single-port setting on the quality of acquired skills, and transferred with the straight and curved instruments for the basic laparoscopic tasks, and highlight the importance of a special laparoscopic training curriculum. A prospective study on a box trainer in single-port setting was conducted using 2 groups. Each group performed 2 tasks on the box trainer in single-port setting. Group-S used conventional straight laparoscopic instruments, and Group-C used curved laparoscopic instruments. Learning curves were obtained by daily measurements recorded in 7-day sessions. On the last day, the 2 groups changed instruments between each other. 1st Department of Surgery, Semmelweis University of Medicine from Budapest, Hungary, a university teaching hospital. In all, 20 fifth-year medical students were randomized into 2 groups. None of them had any laparoscopic or endoscopic experience. Participation was voluntary. Although Group-S performed all tasks significantly faster than Group-C on the first day, the difference proved to be nonsignificant on the last day. All participants achieved significantly shorter task completion time on the last day than on the first day, regardless of the instrument they used. Group-S showed improvement of 63.5%, and Group-C 69.0% improvement by the end of the session. After swapping the instruments, Group-S reached significantly higher task completion time with curved instruments, whereas Group-C showed further progression of 8.9% with straight instruments. Training with curved instruments in a single-port setting allows for a better acquisition of skills in a shorter period. For this reason, there is a need for proficiency-based conventional, but also for a single-port, laparoscopic training curriculum in general surgery residency education. Copyright © 2015 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Abnormal gait pattern emerges during curved trajectories in high-functioning Parkinsonian patients walking in line at normal speed

PubMed Central

Godi, Marco; Giardini, Marica; Arcolin, Ilaria; Nardone, Antonio; Giordano, Andrea; Schieppati, Marco

2018-01-01

Background Several patients with Parkinson´s disease (PD) can walk normally along straight trajectories, and impairment in their stride length and cadence may not be easily discernible. Do obvious abnormalities occur in these high-functioning patients when more challenging trajectories are travelled, such as circular paths, which normally implicate a graded modulation in the duration of the interlimb gait cycle phases? Methods We compared a cohort of well-treated mildly to moderately affected PD patients to a group of age-matched healthy subjects (HS), by deliberately including HS spontaneously walking at the same speed of the patients with PD. All participants performed, in random order: linear and circular walking (clockwise and counter-clockwise) at self-selected speed. By means of pressure-sensitive insoles, we recorded walking speed, cadence, duration of single support, double support, swing phase, and stride time. Stride length-cadence relationships were built for linear and curved walking. Stride-to-stride variability of temporal gait parameters was also estimated. Results Walking speed, cadence or stride length were not different between PD and HS during linear walking. Speed, cadence and stride length diminished during curved walking in both groups, stride length more in PD than HS. In PD compared to HS, the stride length-cadence relationship was altered during curved walking. Duration of the double-support phase was also increased during curved walking, as was variability of the single support, swing phase and double support phase. Conclusion The spatio-temporal gait pattern and variability are significantly modified in well-treated, high-functioning patients with PD walking along circular trajectories, even when they exhibit no changes in speed in straight-line walking. The increased variability of the gait phases during curved walking is an identifying characteristic of PD. We discuss our findings in term of interplay between control of balance and of locomotor progression: the former is challenged by curved trajectories even in high-functioning patients, while the latter may not be critically affected. PMID:29750815

Microvascular Anastomosis: Proposition of a Learning Curve.

PubMed

Mokhtari, Pooneh; Tayebi Meybodi, Ali; Benet, Arnau; Lawton, Michael T

2018-04-14

Learning to perform a microvascular anastomosis is one of the most difficult tasks in cerebrovascular surgery. Previous studies offer little regarding the optimal protocols to maximize learning efficiency. This failure stems mainly from lack of knowledge about the learning curve of this task. To delineate this learning curve and provide information about its various features including acquisition, improvement, consistency, stability, and recall. Five neurosurgeons with an average surgical experience history of 5 yr and without any experience in bypass surgery performed microscopic anastomosis on progressively smaller-caliber silastic tubes (Biomet, Palm Beach Gardens, Florida) during 24 consecutive sessions. After a 1-, 2-, and 8-wk retention interval, they performed recall test on 0.7-mm silastic tubes. The anastomoses were rated based on anastomosis patency and presence of any leaks. Improvement rate was faster during initial sessions compared to the final practice sessions. Performance decline was observed in the first session of working on a smaller-caliber tube. However, this rapidly improved during the following sessions of practice. Temporary plateaus were seen in certain segments of the curve. The retention interval between the acquisition and recall phase did not cause a regression to the prepractice performance level. Learning the fine motor task of microvascular anastomosis adapts to the basic rules of learning such as the "power law of practice." Our results also support the improvement of performance during consecutive sessions of practice. The objective evidence provided may help in developing optimized learning protocols for microvascular anastomosis.

Tibiotalocalcaneal arthrodesis with a curved, interlocking, intramedullary nail.

PubMed

Budnar, Vijaya M; Hepple, Steve; Harries, William G; Livingstone, James A; Winson, Ian

2010-12-01

Tibiotalocalcaneal fusion with a straight rod has a risk of damaging the lateral plantar neurovascular structures and may interfere with maintaining normal heel valgus position.We report the results of a prospective study of tibiotalocalcaneal (TTC) arthrodesis with a short, anatomically curved interlocking, intramedullary nail. Forty-five arthrodesis in 42 patients, performed between Jan 2003 and Oct 2008, were prospectively followed. The mean followup was 48 (range, 10 to 74) months. The main indications for the procedure were failed ankle arthrodesis with progressive subtalar arthritis, failed ankle arthroplasty and complex hindfoot deformity. The outcome was measured by a combination of pre and postoperative clinical examination, AOFAS hindfoot scores, SF-12 scores and radiological assessment. Union rate was 89% (40/45). Eighty-two percent (37/45) reported improvement in pain and 73% (33/45) had improved foot function. Satisfactory hindfoot alignment was achieved in 84% (38/45). Postoperatively there was a mean improvement in the AOFAS score of 37. Complications included a below knee amputation for persistent deep infection, five nonunions, and three delayed unions. Four nails, six proximal and six distal locking screws were removed for various causes. Other complications included two perioperative fractures, four superficial wound infections and one case of lateral plantar nerve irritation. With a short, anatomically curved intramedullary nail, we had a high rate of tibiotalocalcaneal fusion with minimal plantar neurovascular complications. We believe a short, curved intramedullary nail, with its more lateral entry point, helped maintain hindfoot alignment.

Proctorship and mentoring: Its backbone and application in robotic surgery.

PubMed

Santok, Glen Denmer; Raheem, Ali Abdel; Kim, Lawrence Hc; Chang, Kidon; Chung, Byung Ha; Choi, Young Deuk; Rha, Koon Ho

2016-12-01

In pursuit of continuing medical education in robotic surgery, several forms of training have been implemented. This variable application of curriculum has brought acquisition of skills in a heterogeneous and unstandardized fashion from different parts of the world. Recently, efforts have been made to provide cost effective and well-structured curricula with the aim of bridging the gap between formal fellowship training and short courses. Proctorship training has been implicated on some curriculum to provide excellent progression during the learning curve while ensuring patient safety.

136. Linn Cove Viaduct. This is the first precast concrete ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

136. Linn Cove Viaduct. This is the first precast concrete segmental viaduct to be built with the progressive method in the United States. It contains nearly every type of highway geometry within its length. With its super elevation of up to ten degrees and its tight horizontal and spiral curves, it was the most complicated bridge of its type built to that time looking south-southwest. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

256. Linn Cove Viaduct. This is the first precast concrete ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

256. Linn Cove Viaduct. This is the first precast concrete segmental concrete segmental viaduct to be built with the progressive method in the United States. It contains nearly every type of highway construction within its length. With is super elevation of up to ten degrees and its tight horizontal and spiral curves, it was the most complicated bridge of its type built to that time. Looking south-southwest. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

Magnetic and Optical Properties of Submicron-Size Hollow Spheres

PubMed Central

Ye, Quan-Lin; Yoshikawa, Hirofumi; Awaga, Kunio

2010-01-01

Magnetic hollow spheres with a controlled diameter and shell thickness have emerged as an important class of magnetic nanomaterials. The confined hollow geometry and pronouncedly curved surfaces induce unique physical properties different from those of flat thin films and solid counterparts. In this paper, we focus on recent progress on submicron-size spherical hollow magnets (e.g., cobalt- and iron-based materials), and discuss the effects of the hollow shape and the submicron size on magnetic and optical properties.

TRACING CO-REGULATORY NETWORK DYNAMICS IN NOISY, SINGLE-CELL TRANSCRIPTOME TRAJECTORIES.

PubMed

Cordero, Pablo; Stuart, Joshua M

2017-01-01

The availability of gene expression data at the single cell level makes it possible to probe the molecular underpinnings of complex biological processes such as differentiation and oncogenesis. Promising new methods have emerged for reconstructing a progression 'trajectory' from static single-cell transcriptome measurements. However, it remains unclear how to adequately model the appreciable level of noise in these data to elucidate gene regulatory network rewiring. Here, we present a framework called Single Cell Inference of MorphIng Trajectories and their Associated Regulation (SCIMITAR) that infers progressions from static single-cell transcriptomes by employing a continuous parametrization of Gaussian mixtures in high-dimensional curves. SCIMITAR yields rich models from the data that highlight genes with expression and co-expression patterns that are associated with the inferred progression. Further, SCIMITAR extracts regulatory states from the implicated trajectory-evolvingco-expression networks. We benchmark the method on simulated data to show that it yields accurate cell ordering and gene network inferences. Applied to the interpretation of a single-cell human fetal neuron dataset, SCIMITAR finds progression-associated genes in cornerstone neural differentiation pathways missed by standard differential expression tests. Finally, by leveraging the rewiring of gene-gene co-expression relations across the progression, the method reveals the rise and fall of co-regulatory states and trajectory-dependent gene modules. These analyses implicate new transcription factors in neural differentiation including putative co-factors for the multi-functional NFAT pathway.

Urine Trefoil Factors as Prognostic Biomarkers in Chronic Kidney Disease.

PubMed

Yamanari, Toshio; Sugiyama, Hitoshi; Tanaka, Keiko; Morinaga, Hiroshi; Kitagawa, Masashi; Onishi, Akifumi; Ogawa-Akiyama, Ayu; Kano, Yuzuki; Mise, Koki; Ohmoto, Yasukazu; Shikata, Kenichi; Wada, Jun

2018-01-01

Trefoil factor family (TFF) peptides are increased in serum and urine in patients with chronic kidney disease (CKD). However, whether the levels of TFF predict the progression of CKD remains to be elucidated. We determined the TFF levels using peptide-specific ELISA in spot urine samples and performed a prospective cohort study. The association between the levels of urine TFFs and other urine biomarkers as well as the renal prognosis was analyzed in 216 CKD patients (mean age: 53.7 years, 47.7% female, 56.9% with chronic glomerulonephritis, and mean eGFR: 58.5 ml/min/1.73 m 2 ). The urine TFF1 and TFF3 levels significantly increased with the progression of CKD stages, but not the urine TFF2 levels. The TFF1 and TFF3 peptide levels predicted the progression of CKD ≥ stage 3b by ROC analysis (AUC 0.750 and 0.879, resp.); however, TFF3 alone predicted CKD progression in a multivariate logistic regression analysis (odds ratio 3.854, 95% confidence interval 1.316-11.55). The Kaplan-Meier survival curves demonstrated that patients with a higher TFF1 and TFF3 alone, or in combination with macroalbuminuria, had a significantly worse renal prognosis. The data suggested that urine TFF peptides are associated with renal progression and the outcomes in patients with CKD.

Urine Trefoil Factors as Prognostic Biomarkers in Chronic Kidney Disease

PubMed Central

Yamanari, Toshio; Tanaka, Keiko; Morinaga, Hiroshi; Kitagawa, Masashi; Onishi, Akifumi; Ogawa-Akiyama, Ayu; Kano, Yuzuki; Mise, Koki; Ohmoto, Yasukazu; Shikata, Kenichi

2018-01-01

Introduction Trefoil factor family (TFF) peptides are increased in serum and urine in patients with chronic kidney disease (CKD). However, whether the levels of TFF predict the progression of CKD remains to be elucidated. Methods We determined the TFF levels using peptide-specific ELISA in spot urine samples and performed a prospective cohort study. The association between the levels of urine TFFs and other urine biomarkers as well as the renal prognosis was analyzed in 216 CKD patients (mean age: 53.7 years, 47.7% female, 56.9% with chronic glomerulonephritis, and mean eGFR: 58.5 ml/min/1.73 m2). Results The urine TFF1 and TFF3 levels significantly increased with the progression of CKD stages, but not the urine TFF2 levels. The TFF1 and TFF3 peptide levels predicted the progression of CKD ≥ stage 3b by ROC analysis (AUC 0.750 and 0.879, resp.); however, TFF3 alone predicted CKD progression in a multivariate logistic regression analysis (odds ratio 3.854, 95% confidence interval 1.316–11.55). The Kaplan-Meier survival curves demonstrated that patients with a higher TFF1 and TFF3 alone, or in combination with macroalbuminuria, had a significantly worse renal prognosis. Conclusion The data suggested that urine TFF peptides are associated with renal progression and the outcomes in patients with CKD. PMID:29850501

Decision Making of Graduation in Patients With Early-Onset Scoliosis at the End of Distraction-Based Programs: Risks and Benefits of Definitive Fusion.

PubMed

Pizones, Javier; Martín-Buitrago, Mar Pérez; Sánchez Márquez, José Miguel; Fernández-Baíllo, Nicomedes; Baldan-Martin, Montserrat; Sánchez Pérez-Grueso, Francisco Javier

Retrospective comparative analysis. Study early-onset scoliosis (EOS) graduated patients to establish founded criteria for graduation decision making and determine the risks and benefits of definitive fusion. EOS is treated by growth-friendly techniques until skeletal maturity. Afterwards, patients can be "graduated," either by definitive fusion (posterior spinal fusion [PSF]) or by retaining the previous implants (Observation) with no additional surgery. Criteria for this decision making and the outcomes of definitive fusion are still underexplored. We analyzed a consecutive cohort of "graduated" patients after a distraction-based lengthening program. We gathered demographic, radiographic, and surgical data. The results of the two final treatment options were compared after 2 years' follow-up. A total of 32 patients were included. Four patients had incomplete records. Thirteen underwent PSF, and 15 were observed. The mean age at initial treatment was 8 ± 3 years, with a mean follow-up of 8.3 ± 2.9 years. Both groups had similar preoperative and final radiographic parameters (p > .05). The criteria for undergoing PSF were as follows: implant-related complications, main curve magnitude (PSF = 63.2° ± 9° vs. OBS = 47.9° ± 15°; p = .008), curve progression >10°, and sagittal misalignment (SVA). During PSF 12/13 patients underwent multiple osteotomies, one vertebrectomy, and 3 costoplasties. Surgical time was 291.5 ± 58 minutes; blood loss was 946 ± 375 mL; and the number of levels fused was 13.7. Coronal deformity was corrected 31%, T1-S1 length gained was 31 ± 19.6 mm and T1-T12 length gained was 9.3 ± 39 mm; kyphosis was reduced by 22%. However, coronal balance worsened by 2.3 ± 30.8 mm. No major complications were encountered in these patients. Graduation by PSF depended on unacceptable or progressive major curve deformity, sagittal misalignment, or complications with previous implants. Observation depended on curve stabilization, Cobb <50°, and coronal misalignment <20 mm. Definitive fusion effectively corrected coronal and sagittal deformity and increased trunk height. However, it exposed patients to a very demanding surgery without improvement in coronal balance. Level III, therapeutic. Copyright © 2017 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.

Ability to Discriminate Between Sustainable and Unsustainable Heat Stress Exposures-Part 2: Physiological Indicators.

PubMed

Garzón-Villalba, Ximena P; Wu, Yougui; Ashley, Candi D; Bernard, Thomas E

2017-07-01

There are times when it is not practical to assess heat stress using environmental metrics and metabolic rate, and heat strain may provide an alternative approach. Heat strain indicators have been used for decades as tools for monitoring physiological responses to work in hot environments. Common indicators of heat strain are body core temperature (assessed here as rectal temperature Tre), heart rate (HR), and average skin temperature (Tsk). Data collected from progressive heat stress trials were used to (1) demonstrate if physiological heat strain indicators (PHSIs) at the upper limit of Sustainable heat stress were below generally accepted limits; (2) suggest values for PHSIs that demonstrate a Sustainable level of heat stress; (3) suggest alternative PHSIs; and (4) determine if metabolic rate was an effect modifier. Two previous progressive heat stress studies included 176 trials with 352 pairs of Sustainable and Unsustainable exposures over a range of relative humidities and metabolic rates using 29 participants. To assess the discrimination ability of PHSIs, conditional logistic regression and stepwise logistic regression were used to find the best combinations of predictors of Unsustainable exposures. The accuracy of the models was assessed using receiver operating characteristic curves. Current recommendations for physiological heat strain limits were associated with probabilities of Unsustainable greater than 0.5. Screening limits for Sustainable heat stress were Tre of 37.5°C, HR of 105 bpm, and Tsk of 35.8°C. Tsk alone resulted in an area under the curve of 0.85 and the combination of Tsk and HR (area under the curve = 0.88) performed the best. The adjustment for metabolic rate was statistically significant for physiological strain index or ∆Tre-sk as main predictors, but its effect modification was negligible and could be ignored. Based on the receiver operating characteristic curve, PHSIs (Tre, HR, and Tsk) can accurately predict Unsustainable heat stress exposures. Tsk alone or in combination with HR has a high sensitivity, and makes better discriminations than the other PHSIs under relatively constant exposure (metabolic rate and environment) for an hour or so. Screening limits with high sensitivity, however, have low thresholds that limit utility. To the extent that the observed strain is low, there is good evidence that the exposure is Sustainable. © The Author 2017. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Pedicle screw versus hybrid posterior instrumentation for dystrophic neurofibromatosis scoliosis.

PubMed

Wang, Jr-Yi; Lai, Po-Liang; Chen, Wen-Jer; Niu, Chi-Chien; Tsai, Tsung-Ting; Chen, Lih-Huei

2017-06-01

Surgical management of severe rigid dystrophic neurofibromatosis (NF) scoliosis is technically demanding and produces varying results. In the current study, we reviewed 9 patients who were treated with combined anterior and posterior fusion using different types of instrumentation (i.e., pedicle screw, hybrid, and all-hook constructs) at our institute.Between September 2001 and July 2010 at our institute, 9 patients received anterior release/fusion and posterior fusion with different types of instrumentation, including a pedicle screw construct (n = 5), a hybrid construct (n = 3), and an all-hook construct (n = 1). We compared the pedicle screw group with the hybrid group to analyze differences in preoperative curve angle, immediate postoperative curve reduction, and latest follow-up curve angle.The mean follow-up period was 9.5 ± 2.9 years. The average age at surgery was 10.3 ± 3.9 years. The average preoperative scoliosis curve was 61.3 ± 13.8°, and the average preoperative kyphosis curve was 39.8 ± 19.7°. The average postoperative scoliosis and kyphosis curves were 29.7 ± 10.7° and 21.0 ± 13.5°, respectively. The most recent follow-up scoliosis and kyphosis curves were 43.4 ± 17.3° and 29.4 ± 18.9°, respectively. There was no significant difference in the correction angle (either coronal or sagittal), and there was no significant difference in the loss of sagittal correction between the pedicle screw construct group and the hybrid construct group. However, the patients who received pedicle screw constructs had significantly less loss of coronal correction (P < .05). Two patients with posterior instrumentation, one with an all-hook construct and the other with a hybrid construct, required surgical revision because of progression of deformity.It is difficult to intraoperatively correct dystrophic deformity and to maintain this correction after surgery. Combined anterior release/fusion and posterior fusion using either a pedicle screw construct or a hybrid construct provide similar curve corrections both sagittally and coronally. After long-term follow-up, sagittal correction was maintained with both constructs. However, patients treated with posterior instrumentation using pedicle screw constructs had significantly less loss of coronal correction.

Pedicle screw versus hybrid posterior instrumentation for dystrophic neurofibromatosis scoliosis

PubMed Central

Wang, Jr-Yi; Lai, Po-Liang; Chen, Wen-Jer; Niu, Chi-Chien; Tsai, Tsung-Ting; Chen, Lih-Huei

2017-01-01

Abstract Surgical management of severe rigid dystrophic neurofibromatosis (NF) scoliosis is technically demanding and produces varying results. In the current study, we reviewed 9 patients who were treated with combined anterior and posterior fusion using different types of instrumentation (i.e., pedicle screw, hybrid, and all-hook constructs) at our institute. Between September 2001 and July 2010 at our institute, 9 patients received anterior release/fusion and posterior fusion with different types of instrumentation, including a pedicle screw construct (n = 5), a hybrid construct (n = 3), and an all-hook construct (n = 1). We compared the pedicle screw group with the hybrid group to analyze differences in preoperative curve angle, immediate postoperative curve reduction, and latest follow-up curve angle. The mean follow-up period was 9.5 ± 2.9 years. The average age at surgery was 10.3 ± 3.9 years. The average preoperative scoliosis curve was 61.3 ± 13.8°, and the average preoperative kyphosis curve was 39.8 ± 19.7°. The average postoperative scoliosis and kyphosis curves were 29.7 ± 10.7° and 21.0 ± 13.5°, respectively. The most recent follow-up scoliosis and kyphosis curves were 43.4 ± 17.3° and 29.4 ± 18.9°, respectively. There was no significant difference in the correction angle (either coronal or sagittal), and there was no significant difference in the loss of sagittal correction between the pedicle screw construct group and the hybrid construct group. However, the patients who received pedicle screw constructs had significantly less loss of coronal correction (P < .05). Two patients with posterior instrumentation, one with an all-hook construct and the other with a hybrid construct, required surgical revision because of progression of deformity. It is difficult to intraoperatively correct dystrophic deformity and to maintain this correction after surgery. Combined anterior release/fusion and posterior fusion using either a pedicle screw construct or a hybrid construct provide similar curve corrections both sagittally and coronally. After long-term follow-up, sagittal correction was maintained with both constructs. However, patients treated with posterior instrumentation using pedicle screw constructs had significantly less loss of coronal correction. PMID:28562548

Real-world effectiveness of everolimus-based therapy versus fulvestrant monotherapy in HR(+)/HER2(-) metastatic breast cancer.

PubMed

Hao, Yanni; Lin, Peggy L; Xie, Jipan; Li, Nanxin; Koo, Valerie; Ohashi, Erika; Wu, Eric Q; Rogerio, Jaqueline

2015-08-01

Assessing real-world effectiveness of everolimus-based therapy (EVE) versus fulvestrant monotherapy (FUL) among postmenopausal women with hormone receptor-positive (HR(+))/HER2(-) metastatic breast cancer (mBC) after progression on nonsteroidal aromatase inhibitor (NSAI). Medical charts of community-based patients who received EVE or FUL for mBC after NSAI were examined. Progression-free survival (PFS), time on treatment and time to chemotherapy were compared using Kaplan-Meier curves and Cox proportional hazards models adjusting for line of therapy and patient characteristics. 192 patients received EVE and 156 FUL. After adjusting for patient characteristics, EVE was associated with significantly longer PFS than FUL (hazard ratio: 0.71; p = 0.045). EVE was associated with better PFS than FUL among NSAI-refractory postmenopausal HR(+)/HER2(-) mBC patients.

Treatment of Combined Spinal Deformity in Patient with Ollier Disease and Abnormal Vertebrae

PubMed Central

Ryabykh, S. О.; Gubin, A. V.; Prudnikova, О. G.; Kobyzev, А. Е.

2012-01-01

We report staged treatment of severe combined spinal deformity in an 11-year-old patient with Ollier disease and abnormal cervical vertebra. Combined scoliosis with systemic pathology and abnormal vertebrae is a rare condition and features atypical deformity location and rapid progression rate and frequently involves the rib cage and pelvis, disturbing the function of chest organs and skeleton. Progressive deformity resulted in cachexia and acute respiratory failure. A halo-pelvic distraction device assembled of Ilizarov components was employed for a staged surgical treatment performed for lifesaving indications. After vital functions stabilized, the scoliosis curve of the cervical spine was corrected and fixed with a hybrid system of transpedicular supporting points, connecting rods, and connectors that provided staged distraction during growth. The treatment showed good functional and cosmetic result. PMID:24436859

Cation activation of the pig kidney sodium pump: transmembrane allosteric effects of sodium.

PubMed Central

Karlish, S J; Stein, W D

1985-01-01

We have studied activation by Na or Rb ions of different transport modes of the Na-K pump, using phospholipid vesicles reconstituted with pig kidney Na-K-ATPase. The shape of the activation curves, sigmoid or quasi-hyperbolic, depends on the nature of the cation at the opposite surface and not on the specific mode of transport. ATP-dependent Na uptake into K-containing vesicles (Na-K exchange) is activated by cytoplasmic Na along a highly sigmoid curve in the absence of extracellular Na (Hill number, nH = 1.9). Activation displays progressively less-sigmoid curves as extracellular Na is raised to 150 mM (nH = 1.2). The maximal rate of the Na-K exchange is not affected. Na is not transported from the extracellular face by the pump in the presence of excess extracellular K, and the transmembrane effects of the extracellular Na are therefore 'allosteric' in nature. ATP-dependent Na-Na exchange (Lee & Blostein, 1980) and classical ATP-plus-ADP-dependent Na-Na exchange are activated by cytoplasmic Na along hyperbolic curves. ATP-dependent Na uptake into Tris-containing vesicles is activated by cytoplasmic Na along a somewhat sigmoidal curve. (ATP + Pi)-dependent Rb-Rb exchange is activated by cytoplasmic and extracellular Rb along strictly hyperbolic curves. The same applies for Rb-Rb exchange in the presence or absence of ATP or Pi alone. The presence of a high concentration of extracellular Na together with extracellular Rb induces a sigmoidal activation by cytoplasmic Rb of (ATP + Pi)-dependent Rb-Rb exchange (nH = 1.45) but does not affect the maximal rate of exchange. Slow passive Rb fluxes through the pump observed in the absence of other pump ligands (see Karlish & Stein, 1982 alpha) are activated by cytoplasmic Rb along a strictly hyperbolic curve with extracellular Rb, nH = 1.0 (Rb-Rb exchange), along a strongly sigmoid curve with extracellular Na, nH = 1.5 (Rb-Na exchange), and along less-sigmoid curves with extracellular Tris, nH = 1.24 (net Rb flux) or extracellular Li, nH = 1.2 (Rb-Li exchange). Activation of the passive Rb fluxes by extracellular Rb is hyperbolic in the presence of cytoplasmic Rb, Li or Tris but is sigmoid in the presence of cytoplasmic Na (nH = 1.36). Inhibition by cytoplasmic Na of passive Rb fluxes from the cytoplasmic to the extracellular face of the pump depends on the nature of the cation at the extracellular surface.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:2582111

Characterization of Damage Progression in SCS-6/timetal 21S (0)4 Under Thermomechanical Fatigue Loadings

NASA Technical Reports Server (NTRS)

Castelli, Michael G.

1994-01-01

A detailed experimental investigation was performed at a single maximum cyclic stress (sigma max) level to physically characterize the progression of thermomechanical fatigue (lW) damage in continuously reinforced (0 deg) SCS-6/Timetal 21S, a titanium matrix composite. In-phase (IP) and out of-phase (OP) loadings were investigated at sigma max = 1000 MPa with a temperature cycle from 150 to 6500 C. Damage progression, in terms of macroscopic property degradation, was experimentally quantified through an advanced TMF test methodology which incorporates explicit measurements of the isothermal static moduli at the TMF temperature extremes and the coefficient of thermal expansion (CTE) as functions of the TMF cycles. Detailed characterization of the physical damage progression at the microstructural level was performed by interrupting multiple TMF tests at various stages of mechanical property degradation and analyzing the microstructure through extensive destructive metallography. Further, the extent of damage was also quantified through residual static strength measurements. Results indicated that damage initiation occurred very early in cyclic life (N less than 0.1Nf) for both the IP and OP TMF loadings. IP TMF damage was found to be dominated by fiber breakage with a physical damage progression in the microstructure which was difficult to quantify. OP TMF loadings produced matrix cracking exclusively associated with surface initiations. Here, damage progression was easily distinguished in terms of both the number of cracks and their relative inward progressions toward the outer fiber rows with increased cycling. The point at which the leading cracks reached the outer fiber rows (when localized fiber/matrix de-bonding and matrix crack bridging occurred) appeared to be reflected in the macroscopic property degradation curves.

Multicenter phase 2 study of patupilone for recurrent or progressive brain metastases from non-small cell lung cancer.

PubMed

Nayak, Lakshmi; DeAngelis, Lisa M; Robins, H Ian; Govindan, Ramaswamy; Gadgeel, Shirish; Kelly, Karen; Rigas, James R; Peereboom, David M; Rosenfeld, Steven S; Muzikansky, Alona; Zheng, Ming; Urban, Patrick; Abrey, Lauren E; Omuro, Antonio; Wen, Patrick Y

2015-12-01

Treatment options for patients with non-small cell lung cancer (NSCLC) with brain metastases are limited. Patupilone (EPO906), a blood-brain barrier-penetrating, microtubule-targeting, cytotoxic agent, has shown clinical activity in phase 1/2 studies in patients with NSCLC. This study evaluates the efficacy, pharmacokinetics, and safety of patupilone in NSCLC brain metastases. Adult patients with NSCLC and confirmed progressive brain metastases received patupilone intravenously at 10 mg/m(2) every 3 weeks. The primary endpoint of this multinomial 2-stage study combined early progression (EP; death or progression within 3 weeks) and progression-free survival at 9 weeks (PFS9w) to determine drug activity. Fifty patients with a median age of 60 years (range, 33-74 years) were enrolled; the majority were men (58%), and most had received prior therapy for brain metastases (98%). The PFS9w rate was 36%, and the EP rate was 26%. Patupilone blood pharmacokinetic analyses showed mean areas under the concentration-time curve from time zero to 504 hours for cycles 1 and 3 of 1544 and 1978 ng h/mL, respectively, and a mean steady state distribution volume of 755 L/m(2) . Grade 3/4 adverse events (AEs), regardless of their relation with the study drug, included diarrhea (24%), pulmonary embolisms (8%), convulsions (4%), and peripheral neuropathy (4%). All patients discontinued the study drug: 31 (62%) for disease progression and 13 (26%) for AEs. Twenty-five of 32 deaths were due to brain metastases. The median time to progression and the overall survival were 3.2 and 8.8 months, respectively. This is the first prospective study of chemotherapy for recurrent brain metastases from NSCLC. In this population, patupilone demonstrated activity in heavily treated patients. © 2015 American Cancer Society.

Feasibility and safety of extended adjuvant temozolomide beyond six cycles for patients with glioblastoma.

PubMed

Hsieh, S Yp; Chan, D Tm; Kam, M Km; Loong, H Hf; Tsang, W K; Poon, D Mc; Ng, S Cp; Poon, W S

2017-12-01

Temozolomide is the first chemotherapeutic agent proven effective for patients with newly diagnosed glioblastoma. The drug is well tolerated for its low toxicity. The current standard practice is concomitant chemoradiotherapy for 6 weeks followed by 6 cycles of adjuvant temozolomide. Some Caucasian studies have suggested that patients might benefit from extended adjuvant cycles of temozolomide (>6 cycles) to lengthen both progression-free survival and overall survival. In the present study, we compared differences in survival and toxicity profile between patients who received conventional 6-cycle temozolomide and those who received more than 6 cycles of temozolomide. Patients with newly diagnosed glioblastoma without progressive disease and completed concomitant chemoradiotherapy during a 4-year period were studied. Progression-free survival was compared using Kaplan-Meier survival curves. t Test, U test, and correlation were chosen accordingly to examine the impact of age, extent of resection, MGMT promoter methylation status and adjuvant cycles on progression-free survival. For factors with a P value of <0.05 in univariate analyses, Cox regression hazard model was adopted to determine the strongest factors related to progression-free survival. The median progression-free survival was 17.0 months for patients who received 6 cycles of temozolomide (n=7) and 43.4 months for those who received more than 6 cycles (n=7) [P=0.007, log-rank test]. Two patients in the former group and one in the latter group encountered grade 1 toxicity and recovered following dose adjustment. Cycles of adjuvant temozolomide were correlated with progression-free survival (P=0.016, hazard ratio=0.68). Extended cycles of temozolomide are safe and feasible for Chinese patients with disease responsive to temozolomide.

Galectin-3 Reflects the Echocardiographic Grades of Left Ventricular Diastolic Dysfunction.

PubMed

Ansari, Uzair; Behnes, Michael; Hoffmann, Julia; Natale, Michele; Fastner, Christian; El-Battrawy, Ibrahim; Rusnak, Jonas; Kim, Seung Hyun; Lang, Siegfried; Hoffmann, Ursula; Bertsch, Thomas; Borggrefe, Martin; Akin, Ibrahim

2018-07-01

The level of Galectin-3 (Gal-3) protein purportedly reflects an ongoing cardiac fibrotic process and has been associated with ventricular remodeling, which is instrumental in the development of heart failure with preserved ejection fraction (HFpEF) syndrome. The aim of this study was to investigate the potential use of Gal-3 in improved characterization of the grades of diastolic dysfunction as defined by echocardiography. Seventy HFpEF patients undergoing routine echocardiography were prospectively enrolled in the present monocentric study. Blood samples for measurements of Gal-3 and amino-terminal pro-brain natriuretic peptide (NT-proBNP) were collected within 24 hours pre- or post-echocardiographic examination. The classification of patients into subgroups based on diastolic dysfunction grade permitted detailed statistical analyses of the derived data. The Gal-3 serum levels of all patients corresponded to echocardiographic indices, suggesting HFpEF (E/A, P=0.03 and E/E', P=0.02). Gal-3 was also associated with progressive diastolic dysfunction, and increased levels corresponded to the course of disease (P=0.012). Detailed analyses of ROC curves suggested that Gal-3 levels could discriminate patients with grade III diastolic dysfunction (area under the curve [AUC]=0.770, P=0.005). Gal-3 demonstrates remarkable effectiveness in the diagnosis of patients suffering from severe grade diastolic dysfunction. Increasing levels of Gal-3 possibly reflect the progressive course of HFpEF, as classified by the echocardiographic grades of diastolic dysfunction. © The Korean Society for Laboratory Medicine.

Progressive collapse of a two-story reinforced concrete frame with embedded smart aggregates

NASA Astrophysics Data System (ADS)

Laskar, Arghadeep; Gu, Haichang; Mo, Y. L.; Song, Gangbing

2009-07-01

This paper reports the experimental and analytical results of a two-story reinforced concrete frame instrumented with innovative piezoceramic-based smart aggregates (SAs) and subjected to a monotonic lateral load up to failure. A finite element model of the frame is developed and analyzed using a computer program called Open system for earthquake engineering simulation (OpenSees). The finite element analysis (FEA) is used to predict the load-deformation curve as well as the development of plastic hinges in the frame. The load-deformation curve predicted from FEA matched well with the experimental results. The sequence of development of plastic hinges in the frame is also studied from the FEA results. The locations of the plastic hinges, as obtained from the analysis, were similar to those observed during the experiment. An SA-based approach is also proposed to evaluate the health status of the concrete frame and identify the development of plastic hinges during the loading procedure. The results of the FEA are used to validate the SA-based approach for detecting the locations and occurrence of the plastic hinges leading to the progressive collapse of the frame. The locations and sequential development of the plastic hinges obtained from the SA-based approach corresponds well with the FEA results. The proposed SA-based approach, thus validated using FEA and experimental results, has a great potential to be applied in the health monitoring of large-scale civil infrastructures.

Progress of statistical analysis in biomedical research through the historical review of the development of the Framingham score.

PubMed

Ignjatović, Aleksandra; Stojanović, Miodrag; Milošević, Zoran; Anđelković Apostolović, Marija

2017-12-02

The interest in developing risk models in medicine not only is appealing, but also associated with many obstacles in different aspects of predictive model development. Initially, the association of biomarkers or the association of more markers with the specific outcome was proven by statistical significance, but novel and demanding questions required the development of new and more complex statistical techniques. Progress of statistical analysis in biomedical research can be observed the best through the history of the Framingham study and development of the Framingham score. Evaluation of predictive models comes from a combination of the facts which are results of several metrics. Using logistic regression and Cox proportional hazards regression analysis, the calibration test, and the ROC curve analysis should be mandatory and eliminatory, and the central place should be taken by some new statistical techniques. In order to obtain complete information related to the new marker in the model, recently, there is a recommendation to use the reclassification tables by calculating the net reclassification index and the integrated discrimination improvement. Decision curve analysis is a novel method for evaluating the clinical usefulness of a predictive model. It may be noted that customizing and fine-tuning of the Framingham risk score initiated the development of statistical analysis. Clinically applicable predictive model should be a trade-off between all abovementioned statistical metrics, a trade-off between calibration and discrimination, accuracy and decision-making, costs and benefits, and quality and quantity of patient's life.

Association between progression-free survival and health-related quality of life in oncology: a systematic review protocol

PubMed Central

Kovic, Bruno; Guyatt, Gordon; Brundage, Michael; Thabane, Lehana; Bhatnagar, Neera; Xie, Feng

2016-01-01

Introduction There is an increasing number of new oncology drugs being studied, approved and put into clinical practice based on improvement in progression-free survival, when no overall survival benefits exist. In oncology, the association between progression-free survival and health-related quality of life is currently unknown, despite its importance for patients with cancer, and the unverified assumption that longer progression-free survival indicates improved health-related quality of life. Thus far, only 1 study has investigated this association, providing insufficient evidence and inconclusive results. The objective of this study protocol is to provide increased transparency in supporting a systematic summary of the evidence bearing on this association in oncology. Methods and analysis Using the OVID platform in MEDLINE, Embase and Cochrane databases, we will conduct a systematic review of randomised controlled human trials addressing oncology issues published starting in 2000. A team of reviewers will, in pairs, independently screen and abstract data using standardised, pilot-tested forms. We will employ numerical integration to calculate mean incremental area under the curve between treatment groups in studies for health-related quality of life, along with total related error estimates, and a 95% CI around incremental area. To describe the progression-free survival to health-related quality of life association, we will construct a scatterplot for incremental health-related quality of life versus incremental progression-free survival. To estimate the association, we will use a weighted simple regression approach, comparing mean incremental health-related quality of life with either median incremental progression-free survival time or the progression-free survival HR, in the absence of overall survival benefit. Discussion Identifying direction and magnitude of association between progression-free survival and health-related quality of life is critically important in interpreting results of oncology trials. Systematic evidence produced from our study will contribute to improvement of patient care and practice of evidence-based medicine in oncology. PMID:27591026

Effect of tensile deformation on micromagnetic parameters in 0.2% carbon steel and 2.25Cr-1Mo steel

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

Moorthy, V.; Vaidyanathan, S.; Jayakumar, T.

The influence of prior tensile deformation on the magnetic Barkhausen emission (MBE) and the hysteresis (B-H) curve has been studied in 0.2% carbon steel and 2.25Cr-1Mo steel under different tempered conditions. This study shows that the micromagnetic parameters can be used to identify the four stages of deformation, namely (1) perfectly elastic, (2) microplastic yielding, (3) macroyielding and (4) progressive plastic deformation. However, it is observed that the MBE profile shows more distinct changes at different stages of tensile deformation than the hysteresis curve. It has been established that the beginning of microplastic yielding and macroyielding can be identified frommore » the MBE profile which is not possible from the stress-strain plot. The onset of microplastic yielding can be identified from the decrease in the MBE peak height. The macroyielding can be identified from the merging of the initially present two-peak MBE profile into a single central peak with relatively higher peak height and narrow profile width. The difference between the variation of MBE and hysteresis curve parameters with strain beyond macroyielding indicates the difference in the deformation state of the surface and bulk of the sample.« less

Contrast-enhanced magnetic resonance imaging of pulmonary lesions: description of a technique aiming clinical practice.

PubMed

Koenigkam-Santos, Marcel; Optazaite, Elzbieta; Sommer, Gregor; Safi, Seyer; Heussel, Claus Peter; Kauczor, Hans-Ulrich; Puderbach, Michael

2015-01-01

To propose a technique for evaluation of pulmonary lesions using contrast-enhanced MRI; to assess morphological patterns of enhancement and correlate quantitative analysis with histopathology. Thirty-six patients were prospectively studied. Volumetric-interpolated T1W images were obtained during consecutive breath holds after bolus triggered contrast injection. Volume coverage of first three acquisitions was limited (higher temporal resolution) and last acquisition obtained at 4th min. Two radiologists individually evaluated the patterns of enhancement. Region-of-interest-based signal intensity (SI)-time curves were created to assess quantitative parameters. Readers agreed moderately to substantially concerning lesions' enhancement pattern. SI-time curves could be created for all lesions. In comparison to benign, malignant lesions showed higher values of maximum enhancement, early peak, slope and 4th min enhancement. Early peak >15% showed 100% sensitivity to detect malignancy, maximum enhancement >40% showed 100% specificity. The proposed technique is robust, simple to perform and can be applied in clinical scenario. It allows visual evaluation of enhancement pattern/progression together with creation of SI-time curves and assessment of derived quantitative parameters. Perfusion analysis was highly sensitive to detect malignancy, in accordance to what is recommended by most recent guidelines on imaging evaluation of pulmonary lesions. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

A crowdsourced nickel-and-dime approach to analog OBM research: A behavioral economic framework for understanding workforce attrition.

PubMed

Henley, Amy J; DiGennaro Reed, Florence D; Reed, Derek D; Kaplan, Brent A

2016-09-01

Incentives are a popular method to achieve desired employee performance; however, research on optimal incentive magnitude is lacking. Behavioral economic demand curves model persistence of responding in the face of increasing cost and may be suitable to examine the reinforcing value of incentives on work performance. The present use-inspired basic study integrated an experiential human operant task within a crowdsourcing platform to evaluate the applicability of behavioral economics for quantifying changes in workforce attrition. Participants included 88 Amazon Mechanical Turk Workers who earned either a $0.05 or $0.10 incentive for completing a progressively increasing response requirement. Analyses revealed statistically significant differences in breakpoint between the two groups. Additionally, a novel translation of the Kaplan-Meier survival-curve analyses for use within a demand curve framework allowed for examination of elasticity of workforce attrition. Results indicate greater inelastic attrition in the $0.05 group. We discuss the benefits of a behavioral economic approach to modeling employee behavior, how the metrics obtained from the elasticity of workforce attrition analyses (e.g., P max ) may be used to set goals for employee behavior while balancing organizational costs, and how economy type may have influenced observed outcomes. © 2016 Society for the Experimental Analysis of Behavior.

Urea-induced denaturation of human calcium/calmodulin-dependent protein kinase IV: a combined spectroscopic and MD simulation studies.

PubMed

Naz, Huma; Shahbaaz, Mohd; Haque, Md Anzarul; Bisetty, Krishna; Islam, Asimul; Ahmad, Faizan; Hassan, Md Imtaiyaz

2017-02-01

Calcium/calmodulin-dependent protein kinase IV (CaMKIV) is a multifunctional enzyme which belongs to the Ser/Thr kinase family. CaMKIV plays important role in varieties of biological processes such as gene expression regulation, memory consolidation, bone growth, T-cell maturation, sperm motility, regulation of microtubule dynamics, cell-cycle progression, and apoptosis. To measure stability parameters, urea-induced denaturation of CaMKIV was carried out at pH 7.4 and 25°C, using three different probes, namely far-UV CD, near-UV absorption, and tryptophan fluorescence. A coincidence of normalized denaturation curves of these optical properties suggests that urea-induced denaturation is a two-state process. Analysis of these denaturation curves gave values of 4.20 ± 0.12 kcal mol -1 , 2.95 ± 0.15 M, and 1.42 ± 0.06 kcal mol -1  M -1 for [Formula: see text] (Gibbs free energy change (ΔG D ) in the absence of urea), C m (molar urea concentration ([urea]) at the midpoint of the denaturation curve), and m (=∂ΔG D /∂[urea]), respectively. All these experimental observations have been fully supported by 30 ns molecular dynamics simulation studies.

Pigeons' demand and preference for specific and generalized conditioned reinforcers in a token economy.

PubMed

Tan, Lavinia; Hackenberg, Timothy D

2015-11-01

Pigeons' demand and preference for specific and generalized tokens was examined in a token economy. Pigeons could produce and exchange different colored tokens for food, for water, or for food or water. Token production was measured across three phases, which examined: (1) across-session price increases (typical demand curve method); (2) within-session price increases (progressive-ratio, PR, schedule); and (3) concurrent pairwise choices between the token types. Exponential demand curves were fitted to the response data and accounted for over 90% total variance. Demand curve parameter values, Pmax , Omax and α showed that demand was ordered in the following way: food tokens, generalized tokens, water tokens, both in Phase 1 and in Phase 3. This suggests that the preferences were predictable on the basis of elasticity and response output from the demand analysis. Pmax and Omax values failed to consistently predict breakpoints and peak response rates in the PR schedules in Phase 2, however, suggesting limits on a unitary conception of reinforcer efficacy. The patterns of generalized token production and exchange in Phase 3 suggest that the generalized tokens served as substitutes for the specific food and water tokens. Taken together, the present findings demonstrate the utility of behavioral economic concepts in the analysis of generalized reinforcement. © Society for the Experimental Analysis of Behavior.

Toward computer simulation of high-LET in vitro survival curves.

PubMed

Heuskin, A-C; Michiels, C; Lucas, S

2013-09-21

We developed a Monte Carlo based computer program called MCSC (Monte Carlo Survival Curve) able to predict the survival fraction of cells irradiated in vitro with a broad beam of high linear energy transfer particles. Three types of cell responses are studied: the usual high dose response, the bystander effect and the low-dose hypersensitivity (HRS). The program models the broad beam irradiation and double strand break distribution following Poisson statistics. The progression of cells through the cell cycle is taken into account while the repair takes place. Input parameters are experimentally determined for A549 lung carcinoma cells irradiated with 10 and 20 keV µm(-1) protons, 115 keV µm(-1) alpha particles and for EAhy926 endothelial cells exposed to 115 keV µm(-1) alpha particles. Results of simulations are presented and compared with experimental survival curves obtained for A549 and EAhy296 cells. Results are in good agreement with experimental data for both cell lines and all irradiation protocols. The benefits of MCSC are several: the gain of time that would have been spent performing time-consuming clonogenic assays, the capacity to estimate survival fraction of cell lines not forming colonies and possibly the evaluation of radiosensitivity parameters of given individuals.

[Nutritional status in pediatric intermediate care: Assessment at admission, progression during the stay and after discharge].

PubMed

Hubert, A; Ford-Chessel, C; Berthiller, J; Peretti, N; Javouhey, E; Valla, F V

2016-04-01

Malnutrition, known as a cause of morbidity, has not been studied in children admitted to pediatric intermediate care units. This study aimed to describe the association between patients' nutritional status and the relative severity of illness that characterizes this population. In this prospective longitudinal study, a dedicated nutrition support team assessed the nutritional status of all children, aged 5 days to 18 years, admitted to our university pediatric intermediate care unit (Hôpital Femme-Mère-Enfants, Lyon, France) over one year (2012-2013). Weight, height, body mass index, weight-for-age ratio, height-for-age ratio, and the analysis of growth curves were collected at admission. We monitored patients' weight, which allowed us to detect malnutrition occurrence during the stay, and its progression up to 3 months after discharge. A total of 459 patients were enrolled. Based on the analysis integrating all nutritional indices and the progression of growth curves, malnutrition at admission was detected in 23.8% of children (20.5% and 6.8% suffered from acute and chronic malnutrition, respectively). Based only on the body mass index, malnutrition was detected in 15.5% of children. Chronic disease appeared as a risk factor for malnutrition at admission (P=0.0001) and young age for acute malnutrition (P=0.04). The incidence of acquired malnutrition during the stay (in children with a length of stay > 5 days) was up to 26%, and dyspnea was the only risk factor identified. This population recovered with a normal nutritional status late (66% after 2 months and 16% after 3 months). The prevalence of malnutrition is high in our pediatric intermediate care unit. The occurrence of acquired malnutrition during the stay is frequent. All children should benefit from systematic nutritional assessment at admission as well as careful monitoring during the stay and after discharge, to adapt early and individualized nutritional support. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Early diagnostic of concurrent gear degradation processes progressing under time-varying loads

NASA Astrophysics Data System (ADS)

Guilbault, Raynald; Lalonde, Sébastien

2016-08-01

This study develops a gear diagnostic procedure for the detection of multi- and concurrent degradation processes evolving under time-varying loads. Instead of a conventional comparison between a descriptor and an alarm level, this procedure bases its detection strategy on a descriptor evolution tracking; a lasting descriptor increase denotes the presence of ongoing degradation mechanisms. The procedure works from time domain residual signals prepared in the frequency domain, and accepts any gear conditions as reference signature. To extract the load fluctuation repercussions, the procedure integrates a scaling factor. The investigation first examines a simplification assuming a linear connection between the load and the dynamic response amplitudes. However, while generally valuable, the precision losses associated with large load variations may mask the contribution of tiny flaws. To better reflect the real non-linear relation, the paper reformulates the scaling factor; a power law with an exponent value of 0.85 produces noticeable improvements of the load effect extraction. To reduce the consequences of remaining oscillations, the procedure also includes a filtering phase. During the validation program, a synthetic wear progression assuming a commensurate relation between the wear depth and friction assured controlled evolutions of the surface degradation influence, whereas the fillet crack growth remained entirely determined by the operation conditions. Globally, the tested conditions attest that the final strategy provides accurate monitoring of coexisting isolated damages and general surface deterioration, and that its tracking-detection capacities are unaffected by severe time variations of external loads. The procedure promptly detects the presence of evolving abnormal phenomena. The tests show that the descriptor curve shapes virtually describe the constant wear progression superimposed on the crack length evolution. At the tooth fracture, the mean values of the residual signal evince strong perturbations, while after this episode, the monitoring curves continue signaling the ongoing wear process.

Orbital Light Curves of UU Aquarii in Stunted Outburst

NASA Astrophysics Data System (ADS)

Robertson, J. W.; Honeycutt, R. K.; Henden, A. A.; Campbell, R. T.

2018-02-01

Stunted outbursts are ∼0.ͫ6 eruptions, typically lasting 5–10 days, which are found in some novalike cataclysmic variables, including UU Aqr. The mechanism responsible for stunted outbursts is uncertain but is likely related to an accretion disk instability or to variations in the mass transfer rate. A campaign to monitor the eclipse light curves in UU Aqr has been conducted in order to detect any light curve distortions due to the appearance of a hot spot on the disk at the location of the impact point of the accretion stream. If stunted outbursts are due to a temporary mass transfer enhancement, then predictable deformations of the orbital light curve are expected to occur during such outbursts. This study used 156 eclipses on 135 nights during the years 2000–2012. During this interval, random samples found the system to be in stunted outbursts 4%–5% of the time, yielding ∼7 eclipses obtained during some stage of stunted outburst. About half of the eclipses obtained during stunted outbursts showed clear evidence for hot spot enhancement, providing strong evidence that the stunted outbursts in UU Aqr are associated with mass transfer variations. The other half of the eclipses during stunted outburst showed little or no evidence for hot spot enhancement. Furthermore, there were no systematic changes in the hot spot signature as stunted outbursts progressed. Therefore, we have tentatively attributed the changes in hot spot visibility during stunted outburst to random blobby accretion, which likely further modulates the strength of the accretion stream on orbital timescales.

Statistics-related and reliability-physics-related failure processes in electronics devices and products

NASA Astrophysics Data System (ADS)

Suhir, E.

2014-05-01

The well known and widely used experimental reliability "passport" of a mass manufactured electronic or a photonic product — the bathtub curve — reflects the combined contribution of the statistics-related and reliability-physics (physics-of-failure)-related processes. When time progresses, the first process results in a decreasing failure rate, while the second process associated with the material aging and degradation leads to an increased failure rate. An attempt has been made in this analysis to assess the level of the reliability physics-related aging process from the available bathtub curve (diagram). It is assumed that the products of interest underwent the burn-in testing and therefore the obtained bathtub curve does not contain the infant mortality portion. It has been also assumed that the two random processes in question are statistically independent, and that the failure rate of the physical process can be obtained by deducting the theoretically assessed statistical failure rate from the bathtub curve ordinates. In the carried out numerical example, the Raleigh distribution for the statistical failure rate was used, for the sake of a relatively simple illustration. The developed methodology can be used in reliability physics evaluations, when there is a need to better understand the roles of the statistics-related and reliability-physics-related irreversible random processes in reliability evaluations. The future work should include investigations on how powerful and flexible methods and approaches of the statistical mechanics can be effectively employed, in addition to reliability physics techniques, to model the operational reliability of electronic and photonic products.

Stellar granulation as the source of high-frequency flicker in Kepler light curves

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

Cranmer, Steven R.; Saar, Steven H.; Bastien, Fabienne A.

2014-02-01

A large fraction of cool, low-mass stars exhibit brightness fluctuations that arise from a combination of convective granulation, acoustic oscillations, magnetic activity, and stellar rotation. Much of the short-timescale variability takes the form of stochastic noise, whose presence may limit the progress of extrasolar planet detection and characterization. In order to lay the groundwork for extracting useful information from these quasi-random signals, we focus on the origin of the granulation-driven component of the variability. We apply existing theoretical scaling relations to predict the star-integrated variability amplitudes for 508 stars with photometric light curves measured by the Kepler mission. We alsomore » derive an empirical correction factor that aims to account for the suppression of convection in F-dwarf stars with magnetic activity and shallow convection zones. So that we can make predictions of specific observational quantities, we performed Monte Carlo simulations of granulation light curves using a Lorentzian power spectrum. These simulations allowed us to reproduce the so-called flicker floor (i.e., a lower bound in the relationship between the full light-curve range and power in short-timescale fluctuations) that was found in the Kepler data. The Monte Carlo model also enabled us to convert the modeled fluctuation variance into a flicker amplitude directly comparable with observations. When the magnetic suppression factor described above is applied, the model reproduces the observed correlation between stellar surface gravity and flicker amplitude. Observationally validated models like these provide new and complementary evidence for a possible impact of magnetic activity on the properties of near-surface convection.« less

Reliability of transpulmonary pressure-time curve profile to identify tidal recruitment/hyperinflation in experimental unilateral pleural effusion.

PubMed

Formenti, P; Umbrello, M; Graf, J; Adams, A B; Dries, D J; Marini, J J

2017-08-01

The stress index (SI) is a parameter that characterizes the shape of the airway pressure-time profile (P/t). It indicates the slope progression of the curve, reflecting both lung and chest wall properties. The presence of pleural effusion alters the mechanical properties of the respiratory system decreasing transpulmonary pressure (Ptp). We investigated whether the SI computed using Ptp tracing would provide reliable insight into tidal recruitment/overdistention during the tidal cycle in the presence of unilateral effusion. Unilateral pleural effusion was simulated in anesthetized, mechanically ventilated pigs. Respiratory system mechanics and thoracic computed tomography (CT) were studied to assess P/t curve shape and changes in global lung aeration. SI derived from airway pressure (Paw) was compared with that calculated by Ptp under the same conditions. These results were themselves compared with quantitative CT analysis as a gold standard for tidal recruitment/hyperinflation. Despite marked changes in tidal recruitment, mean values of SI computed either from Paw or Ptp were remarkably insensitive to variations of PEEP or condition. After the instillation of effusion, SI indicates a preponderant over-distension effect, not detected by CT. After the increment in PEEP level, the extent of CT-determined tidal recruitment suggest a huge recruitment effect of PEEP as reflected by lung compliance. Both SI in this case were unaffected. We showed that the ability of SI to predict tidal recruitment and overdistension was significantly reduced in a model of altered chest wall-lung relationship, even if the parameter was computed from the Ptp curve profile.

Biocontrol of Sclerotinia sclerotiorum (Lib.) de Bary on common bean by native lipopeptide-producer Bacillus strains.

PubMed

Sabaté, Daniela C; Brandan, Carolina Pérez; Petroselli, Gabriela; Erra-Balsells, Rosa; Audisio, M Carina

2018-06-01

Bacillus sp. B19, Bacillus sp. P12 and B. amyloliquefaciens B14 were isolated from soils of Salta province, and PGPR properties on the common bean (Phaseolus vulgaris L.) cv. Alubia and antagonistic activity against Sclerotinia sclerotiorum were studied. It was determined that B19 and P12 increased crop germination potential (GP) from the common bean by 14.5% compared to control seeds; these strains also increased root length (10.4 and 15%, respectively) and stem length (20.2 and 30%, respectively) compared to the control; however, as for the B14 strain, no increases in growth parameters were detected. In addition, all the treatments that combined two bacilli: B14 + B19, B14 + P12 and B19 + P12, generated beneficial effects on GP and seedling growth compared to control seeds, but not compared to a single inoculant. B19 and P12 strains synthesized auxins at concentrations of 5.71 and 4.90 mg/mL, respectively, and it was qualitatively determined that they synthesize siderophores. In addition, previous studies have determined that B14 produces auxins in a concentration of 10.10 mg/mL, and qualitatively synthesizes siderophores. The phytosanitary state of the white bean cv. Alubia control seeds revealed bacterial contamination in 87% of all the evaluated seeds and different fungi such as Cladosporium sp., Fusarium sp., and Rhizopus sp. Bean seeds treated with B14, B19 or P12 showed no growth of contaminating bacteria or of pathogenic fungi; in fact, bacilli inoculum development was observed in all seeds. Additionally, B19, P12 and B14 strains inhibited in vitro the development of 9 native S. sclerotiorum strains isolated from the Salta region, with FI ranging between 60 and 100%. The three Bacillus strains synthesized different isoforms of the lipopeptides: surfactin, iturin, and fengycin in the presence of S. sclerotiorum, as determined by MALDI-TOF. In the in vivo trials, when common bean seeds were grown in soils contaminated with S. sclerotiorum, an incidence of 100% was determined when the seeds were not treated with any Bacillus. Seeds treated with the chemical fungicide and sown in S. sclerotiorum-infested soil did not produce seed emergence, while the inoculation of the seeds with B14 + P12, B14 + B19 or B19 + P12 reduced the effect of the pathogen by 46, 43 and 25%, respectively. Disease progression in B14 + P12 and B14 + B19 treatments was significantly lower than in the remaining treatments, with an AUDPC of 873.75 and 1071, respectively. Copyright © 2018 Elsevier GmbH. All rights reserved.

Rapidly progressive Scheuermann's disease in an adolescent after pectus bar placement treated with posterior vertebral-column resection: case report and review of the literature.

PubMed

Sugrue, Patrick A; OʼShaughnessy, Brian A; Blanke, Kathy M; Lenke, Lawrence G

2013-02-15

Case report and review of the literature. This case illustrates the importance of the costosternal complex in maintaining the stability and alignment of the thoracic spine. The patient was iatrogenically destabilized by placement of a pectus bar leading to rapid symptomatic progression of his Scheuermann's kyphosis, ultimately requiring surgical correction. Scheuermann's kyphosis is a disease process defined by strict radiographical and clinical criteria. Surgical treatment is generally recommended for curves greater than 75°. This case demonstrates the critical role of the costosternal complex in maintaining the stability of the thoracic spine. The patient described in this report underwent placement of a pectus bar for correction of symptomatic pectus excavatum. He subsequently developed a progressive symptomatic Scheuermann's kyphosis as a result of the destabilization of his costosternal complex. This patient ultimately required removal of the pectus bar and posterior instrumented kyphosis correction. Progressive symptomatic Scheuermann's kyphosis (105°) corrected by removal of the pectus bar, T11 posterior vertebral-column resection and T4-L3 instrumented posterior spinal fusion. The patient had an uneventful immediate postoperative course. He was discharged neurologically intact with dramatic kyphosis correction and significant symptomatic improvement. Radiographs obtained 3 years postoperatively reveal stable thoracolumbar correction. The costosternal complex plays a critically important role in the intrinsic stability of the thoracic spine. Iatrogenic disruption of the costosternal complex can result in rapid progression of thoracic/thoracolumbar kyphosis in the setting of Scheuermann's disease.

Methotrexate treatment in progressive tubal ectopic pregnancies and hCG-related clinicosurgical implications.

PubMed

Dogan, Askin; Gulhan, Ibrahim; Uyar, Ibrahim; Ekin, Atalay; Gezer, Cenk; Bilgin, Muzaffer; Taner, Cüneyt E; Ertas, Ibrahim E

2016-06-01

Our aim was to evaluate the relationship between the success of methotrexate treatment and β-hCG levels in progressive tubal ectopic pregnancies. We defined a retrospective cohort of 394 progressive tubal ectopic pregnancy patients treated with methotrexate. A single-dose methotrexate protocol using 50 mg/m(2) was administered to patients with progressive tubal ectopic pregnancy. Surgery was performed in patients who exhibited signs of acute abdomen due to tubal rupture. Of 394 patients that received methotrexate treatment, 335 (84.6%) responded to medical treatment, while the remaining 59 (15.36%) underwent surgery due to treatment failure. β-hCG levels in the failure group were significantly higher as compared with the success group at Day 1, Day 4, and Day 7 (2116±3157 vs. 4178±3422, 2062±3551 vs. 4935±4103, and 1532±3007 vs. 3900±4783, respectively). The receiver operating characteristics curve for β-hCG levels at Day 1 was 0.738, with a cutoff value of 1418 mIU/mL, while sensitivity and specificity values reached the optimum for treatment success (83.1% and 59.4%, respectively). Medical treatment with methotrexate achieved an 85.02% success rate for the treatment of progressive tubal ectopic pregnancy, while success rates for medical treatment decreased significantly when initial β-hCG levels were >1418 mIU/mL. Copyright © 2016. Published by Elsevier Taiwan.

The management of scoliosis in children with cerebral palsy: a review

PubMed Central

Gardner, Adrian

2016-01-01

Children who suffer with cerebral palsy (CP) have a significant chance of developing scoliosis during their early years and adolescence. The behavior of this scoliosis is closely associated with the severity of the CP disability and unlike idiopathic scoliosis, it continues to progress beyond skeletal maturity. Conservative measures may slow the progression of the curve, however, surgery remains the only definitive management option. Advances in surgical technique over the last 50 years have provided methods to effectively treat the deformity while also reducing complication rates. The increased risk of surgical complications with these complex patients make decisions about treatment challenging, however with careful pre-operative optimization and post-operative care, surgery can offer a significant improvement in quality of life. This review discusses the development of scoliosis in CP patient, evaluates conservative and surgical treatment options and assesses post-operative outcome. PMID:28097247

Investigation of Micro-Scale Architectural Effects on Damage of Composites

NASA Technical Reports Server (NTRS)

Stier, Bertram; Bednarcyk, Brett A.; Simon, Jaan W.; Reese, Stefanie

2015-01-01

This paper presents a three-dimensional, energy based, anisotropic, stiffness reduction, progressive damage model for composite materials and composite material constituents. The model has been implemented as a user-defined constitutive model within the Abaqus finite element software package and applied to simulate the nonlinear behavior of a damaging epoxy matrix within a unidirectional composite material. Three different composite microstructures were considered as finite element repeating unit cells, with appropriate periodicity conditions applied at the boundaries. Results representing predicted transverse tensile, longitudinal shear, and transverse shear stress-strain curves are presented, along with plots of the local fields indicating the damage progression within the microstructure. It is demonstrated that the damage model functions appropriately at the matrix scale, enabling localization of the damage to simulate failure of the composite material. The influence of the repeating unit cell geometry and the effect of the directionality of the applied loading are investigated and discussed.

Fatigue behavior of a cross-ply ceramic matrix composite subjected to tension-tension cycling with hold time. Master`s thesis

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

Grant, S.A.

This study was carried out to investigate the elevated temperature behavior of the SiC-MAS5 cross- ply (O/9O)4S ceramic matrix composite manufactured by Corning Inc. to fatigue with loading waveforms that combine the characteristics of stress rupture and high cycle fatigue. The test results were compiled in the form of S-N (cycles to failure), S-T (exposure time versus cycles to failure), S-S (energy exposure versus cycles to failure), normalized modulus degradation, strain progression, and hysteresis loop progression. From the mechanical behavior demonstrated by these curves, relationships between the effect of the environment and loading waveform were developed. In addition, a post-mortemmore » SEM analysis of the fracture surface was conducted and the results compared to the mechanical behavior.« less

GENIE - Generation of computational geometry-grids for internal-external flow configurations

NASA Technical Reports Server (NTRS)

Soni, B. K.

1988-01-01

Progress realized in the development of a master geometry-grid generation code GENIE is presented. The grid refinement process is enhanced by developing strategies to utilize bezier curves/surfaces and splines along with weighted transfinite interpolation technique and by formulating new forcing function for the elliptic solver based on the minimization of a non-orthogonality functional. A two step grid adaptation procedure is developed by optimally blending adaptive weightings with weighted transfinite interpolation technique. Examples of 2D-3D grids are provided to illustrate the success of these methods.

Activation of hydrocarbons and the octane number

NASA Technical Reports Server (NTRS)

Peschard, Marcel

1939-01-01

This report presents an examination of the history of research on engine knocking and the various types of fuels used in the investigations of this phenomenon. According to this report, the spontaneous ignition of hydrocarbons doped with oxygen follows the logarithmic law within a certain temperature range, but not above 920 degrees K. Having extended the scope of investigations to prove hydrocarbons, the curves of the mixtures burned by air should then be established by progressive replacement of pure iso-octane with heptane. Pentane was also examined in this report.

Wnt/Beta-Catenin, Foxa2, and CXCR4 Axis Controls Prostate Cancer Progression

DTIC Science & Technology

2013-07-01

NT1 cells with or without Foxa2 were cultured in 5% strip medium in the presence or absence of androgen. Cell growth curve was measured by WTS...assays. Over-expression of Foxa2 increased NT1 cell growth even in the absence of androgen. Figure 3. knocking-down Foxa2 did not affect PC3 cell ...in NeoTag1 cells decreased AR level; however, AR 6 activity did not change. Foxa2 target genes were up-regulated in NT1 /Foxa2 over-expressing

Attaining the Photometric Precision Required by Future Dark Energy Projects

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

Stubbs, Christopher

2013-01-21

This report outlines our progress towards achieving the high-precision astronomical measurements needed to derive improved constraints on the nature of the Dark Energy. Our approach to obtaining higher precision flux measurements has two basic components: 1) determination of the optical transmission of the atmosphere, and 2) mapping out the instrumental photon sensitivity function vs. wavelength, calibrated by referencing the measurements to the known sensitivity curve of a high precision silicon photodiode, and 3) using the self-consistency of the spectrum of stars to achieve precise color calibrations.

Moving up the automation S-curve: The role of the laboratory automation support function in successful pharmaceutical R&D

PubMed Central

Maddux, Randy J.

1995-01-01

The political and economic climate that exists today is a challenging one for the pharmaceutical industry. To effectively compete in today's marketplace, companies must discover and develop truly innovative medicines. The R&D organizations within these companies are under increasing pressure to hold down costs while accomplishing this mission. In this environment of level head count and operating budgets, it is imperative that laboratory management uses resources in the most effective, efficient ways possible. Investment in laboratory automation is a proven tool for doing just that. This paper looks at the strategy and tactics behind the formation and evolution of a central automation/laboratory technology support function at the Glaxo Research Institute. Staffing of the function is explained, along with operating strategy and alignment with the scientific client base. Using the S-curve model of technological progress, both the realized and potential impact on successful R&D automation and laboratory technology development are assessed. PMID:18925012

A dose-responsive model of smoke inhalation injury. Severity-related alteration in cardiopulmonary function.

PubMed Central

Shimazu, T; Yukioka, T; Hubbard, G B; Langlinais, P C; Mason, A D; Pruitt, B A

1987-01-01

The dose responsiveness of selected physiologic indices was studied in a sheep model of smoke inhalation injury. In this model, graded severity of injury was achieved by changing the contact time with smoke (defined by "unit"), whereas other variables were kept constant. Blood gas and cardiopulmonary indices were measured in 70 sheep, including 12 controls, either 24 or 72 hours after exposure to 3, 6, 9, 12, 15, or 18 units of smoke. A 12-unit dose of smoke was fatal within 72 hours and an 18-unit dose was fatal within 24 hours. The best correlation between smoke dose and response was observed in arterial oxygen tension 24 hours after exposure. At 24 hours, most of the cardiopulmonary indices showed significant change only after a 12-unit exposure. Although the exact shape of the dose-response curve could not be defined, sigmoid or curved linear shape was suggested, reflecting the progressive deterioration. Images Fig. 3. Fig. 4A. Fig. 4B. PMID:3606236

Analysis of the Casson and Carreau-Yasuda non-Newtonian blood models in steady and oscillatory flows using the lattice Boltzmann method

NASA Astrophysics Data System (ADS)

Boyd, Joshua; Buick, James M.; Green, Simon

2007-09-01

The lattice Boltzmann method is modified to allow the simulation of non-Newtonian shear-dependent viscosity models. Casson and Carreau-Yasuda non-Newtonian blood viscosity models are implemented and are used to compare two-dimensional Newtonian and non-Newtonian flows in the context of simple steady flow and oscillatory flow in straight and curved pipe geometries. It is found that compared to analogous Newtonian flows, both the Casson and Carreau-Yasuda flows exhibit significant differences in the steady flow situation. In the straight pipe oscillatory flows, both models exhibit differences in velocity and shear, with the largest differences occurring at low Reynolds and Womersley numbers. Larger differences occur for the Casson model. In the curved pipe Carreau-Yasuda model, moderate differences are observed in the velocities in the central regions of the geometries, and the largest shear rate differences are observed near the geometry walls. These differences may be important for the study of atherosclerotic progression.

Monitoring cerebrovascular pressure reactivity with rheoencephalography

NASA Astrophysics Data System (ADS)

Brady, K. M.; Mytar, J. O.; Kibler, K. K.; Easley, R. B.; Koehler, R. C.; Czosnyka, M.; Smielewski, P.; Zweifel, C.; Bodo, M.; Pearce, F. J.; Armonda, R. A.

2010-04-01

Determining optimal perfusion pressure for patients with traumatic brain injury can be accomplished by monitoring the pressure reactivity index, or PRx, which requires an intracranial pressure monitor. We hypothesized that pressure reactivity could be quantified using a rheoencephalography index, or REGx. We measured the REGx and PRx as repetitive, low-frequency linear correlation between arterial blood pressure and intracranial pressure (PRx) or arterial blood pressure and REG pulse amplitude (REGx) in a piglet model of progressive hypotension. We compared the PRx and REGx against a gold standard determination of the lower limit of autoregulation using laser-Doppler measurements of cortical red cell flux. The PRx produced an accurate metric of vascular reactivity in this cohort, with area under the receiver-operator characteristic curves of 0.91. REGx was moderately correlated to the PRx, (Spearman r = 0.63, p < 0.0001; Bland-Altman bias-0.13). The area under the receiver-operator curve for the REGx was 0.86. Disagreement occurred at extremes of hypotension.

Wide-angle camera with multichannel architecture using microlenses on a curved surface.

PubMed

Liang, Wei-Lun; Shen, Hui-Kai; Su, Guo-Dung J

2014-06-10

We propose a multichannel imaging system that combines the principles of an insect's compound eye and the human eye. The optical system enables a reduction in track length of the imaging device to achieve miniaturization. The multichannel structure is achieved by a curved microlens array, and a Hypergon lens is used as the main lens to simulate the human eye, achieving large field of view (FOV). With this architecture, each microlens of the array transmits a segment of the overall FOV. The partial images are recorded in separate channels and stitched together to form the final image of the whole FOV by image processing. The design is 2.7 mm thick, with 59 channels; the 100°×80° full FOV is optimized using ZEMAX ray-tracing software on an image plane. The image plane size is 4.53  mm×3.29  mm. Given the recent progress in the fabrication of microlenses, this image system has the potential to be commercialized in the near future.

Lectures on Dark Matter Physics

NASA Astrophysics Data System (ADS)

Lisanti, Mariangela

Rotation curve measurements from the 1970s provided the first strong indication that a significant fraction of matter in the Universe is non-baryonic. In the intervening years, a tremendous amount of progress has been made on both the theoretical and experimental fronts in the search for this missing matter, which we now know constitutes nearly 85% of the Universe's matter density. These series of lectures provide an introduction to the basics of dark matter physics. They are geared for the advanced undergraduate or graduate student interested in pursuing research in high-energy physics. The primary goal is to build an understanding of how observations constrain the assumptions that can be made about the astro- and particle physics properties of dark matter. The lectures begin by delineating the basic assumptions that can be inferred about dark matter from rotation curves. A detailed discussion of thermal dark matter follows, motivating Weakly Interacting Massive Particles, as well as lighter-mass alternatives. As an application of these concepts, the phenomenology of direct and indirect detection experiments is discussed in detail.

Progress in Developing a New Field-theoretical Crossover Equation-of-State

NASA Technical Reports Server (NTRS)

Rudnick, Joseph; Barmatz, M.; Zhong, Fang

2003-01-01

A new field-theoretical crossover equation-of-state model is being developed. This model of a liquid-gas critical point provides a bridge between the asymptotic equation-of-state behavior close to the transition, obtained by the Guida and Zinn-Justin parametric model [J. Phys. A: Math. Gen. 31, 8103 (1998)], and the expected mean field behavior farther away. The crossover is based on the beta function for the renormalized fourth-order coupling constant and incorporates the correct crossover exponents and critical amplitude ratios in both regimes. A crossover model is now being developed that is consistent with predictions along the critical isochore and along the coexistence curve of the minimal subtraction renormalization approach developed by Dohm and co-workers and recently applied to the O(1) universality class [Phys. Rev. E, 67, 021106 (2003)]. Experimental measurements of the heat capacity at constant volume, isothermal susceptibility, and coexistence curve near the He-3 critical point are being compared to the predictions of this model. The results of these comparisons will be presented.

Radioactive models of type 1 supernovae

NASA Astrophysics Data System (ADS)

Schurmann, S. R.

1983-04-01

In recent years, considerable progress has been made toward understanding Type I supernovae within the context of radioactive energy input. Much effort has gone into determining the peak magnitude of the supernovae, particularly in the B-band, and its relation to the Hubble constant. If the distances inferred for Type I events are at all accurate, and/or the Hubble constant has a value near 50 km per s per Mpc, it is clear that models must reach a peak magnitude approximately -20 in order to be consistent. The present investigation is concerned with models which achieve peak magnitudes near this value and contain 0.8 solar mass of Ni-56. The B-band light curve declines much more rapidly after peak than the bolometric light curve. The mass and velocity of Ni-56 (at least for the A models) are within the region defined by Axelrod (1980) for configurations which produce acceptable spectra at late times. The models are consistent with the absence of a neutron star after the explosion. There remain, however, many difficult problems.

Radioactive models of type 1 supernovae

NASA Technical Reports Server (NTRS)

Schurmann, S. R.

1983-01-01

In recent years, considerable progress has been made toward understanding Type I supernovae within the context of radioactive energy input. Much effort has gone into determining the peak magnitude of the supernovae, particularly in the B-band, and its relation to the Hubble constant. If the distances inferred for Type I events are at all accurate, and/or the Hubble constant has a value near 50 km per s per Mpc, it is clear that models must reach a peak magnitude approximately -20 in order to be consistent. The present investigation is concerned with models which achieve peak magnitudes near this value and contain 0.8 solar mass of Ni-56. The B-band light curve declines much more rapidly after peak than the bolometric light curve. The mass and velocity of Ni-56 (at least for the A models) are within the region defined by Axelrod (1980) for configurations which produce acceptable spectra at late times. The models are consistent with the absence of a neutron star after the explosion. There remain, however, many difficult problems.

ERTS-1 data collection systems used to predict wheat disease severities. [Riley County, Kansas

NASA Technical Reports Server (NTRS)

Kanemasu, E. T.; Schimmelpfenning, H.; Choy, E. C.; Eversmeyer, M. G.; Lenhert, D.

1974-01-01

The author has identified the following significant results. The feasibility of using the data collection system on ERTS-1 to predict wheat leaf rust severity and resulting yield loss was tested. Ground-based data collection platforms (DCP'S), placed in two commercial wheat fields in Riley County, Kansas, transmitted to the satellite such meteorological information as maximum and minimum temperature, relative humidity, and hours of free moisture. Meteorological data received from the two DCP'S from April 23 to 29 were used to estimate the disease progress curve. Values from the curve were used to predict the percentage decrease in wheat yields resulting from leaf rust. Actual decrease in yield was obtained by applying a zinc and maneb spray (5.6 kg/ha) to control leaf rust, then comparing yields of the controlled (healthy) and the noncontrolled (rusted) areas. In each field a 9% decrease in yield was predicted by the DCP-derived data; actual decreases were 12% and 9%.

Uncertainty in urban flood damage assessment due to urban drainage modelling and depth-damage curve estimation.

PubMed

Freni, G; La Loggia, G; Notaro, V

2010-01-01

Due to the increased occurrence of flooding events in urban areas, many procedures for flood damage quantification have been defined in recent decades. The lack of large databases in most cases is overcome by combining the output of urban drainage models and damage curves linking flooding to expected damage. The application of advanced hydraulic models as diagnostic, design and decision-making support tools has become a standard practice in hydraulic research and application. Flooding damage functions are usually evaluated by a priori estimation of potential damage (based on the value of exposed goods) or by interpolating real damage data (recorded during historical flooding events). Hydraulic models have undergone continuous advancements, pushed forward by increasing computer capacity. The details of the flooding propagation process on the surface and the details of the interconnections between underground and surface drainage systems have been studied extensively in recent years, resulting in progressively more reliable models. The same level of was advancement has not been reached with regard to damage curves, for which improvements are highly connected to data availability; this remains the main bottleneck in the expected flooding damage estimation. Such functions are usually affected by significant uncertainty intrinsically related to the collected data and to the simplified structure of the adopted functional relationships. The present paper aimed to evaluate this uncertainty by comparing the intrinsic uncertainty connected to the construction of the damage-depth function to the hydraulic model uncertainty. In this way, the paper sought to evaluate the role of hydraulic model detail level in the wider context of flood damage estimation. This paper demonstrated that the use of detailed hydraulic models might not be justified because of the higher computational cost and the significant uncertainty in damage estimation curves. This uncertainty occurs mainly because a large part of the total uncertainty is dependent on depth-damage curves. Improving the estimation of these curves may provide better results in term of uncertainty reduction than the adoption of detailed hydraulic models.

S100A9 and EGFR gene signatures predict disease progression in muscle invasive bladder cancer patients after chemotherapy.

PubMed

Kim, W T; Kim, J; Yan, C; Jeong, P; Choi, S Y; Lee, O J; Chae, Y B; Yun, S J; Lee, S C; Kim, W J

2014-05-01

In our previous gene expression profile analysis, IL1B, S100A8, S100A9, and EGFR were shown to be important mediators of muscle invasive bladder cancer (MIBC) progression. The aim of the present study was to investigate the ability of these gene signatures to predict disease progression after chemotherapy in patients with locally recurrent or metastatic MIBC. Patients with locally advanced MIBC who received chemotherapy were enrolled. The expression signatures of four genes were measured and carried out further functional analysis to confirm our findings. Two of the four genes, S100A9 and EGFR, were determined to significantly influence disease progression (P = 0.023, 0.045, respectively). Based on a receiver operating characteristic curve, a cut-off value for disease progression was determined. Patients with the good-prognostic signature group had a significantly longer time to progression and cancer-specific survival time than those with the poor-prognostic signature group (P < 0.001, 0.042, respectively). In the multivariate Cox regression analysis, gene signature was the only factor that significantly influenced disease progression [hazard ratio: 4.726, confidence interval: 1.623-13.763, P = 0.004]. In immunohistochemical analysis, S100A9 and EGFR positivity were associated with disease progression after chemotherapy. Protein expression of S100A9/EGFR showed modest correlation with gene expression of S100A9/EGFR (r = 0.395, P = 0.014 and r = 0.453, P = 0.004). Our functional analysis provided the evidence demonstrating that expression of S100A9 and EGFR closely associated chemoresistance, and that inhibition of S100A9 and EGFR may sensitize bladder tumor cells to the cisplatin-based chemotherapy. The S100A9/EGFR level is a novel prognostic marker to predict the chemoresponsiveness of patients with locally recurrent or metastatic MIBC.

Non-linear education gradient across the nutrition transition: mothers' overweight and the population education transition.

PubMed

Jeon, Haram; Salinas, Daniel; Baker, David P

2015-12-01

Previous studies found that developed and developing countries present opposite education-overweight gradients but have not considered the dynamics at different levels of national development. An inverted U-shaped curve is hypothesized to best describe the education-overweight association. It is also hypothesized that as the nutrition transition unfolds within nations the shape of education-overweight curve changes. Multilevel logistic regression was used to estimate the moderating effect of the nutrition transition at the population level on the education-overweight gradient. At the individual level, a non-linear estimate of the education association was used to assess the optimal functional form of the association across the nutrition transition. Twenty-two administrations of the Demographic and Health Survey, collected at different time points across the nutrition transition in nine Latin American/Caribbean countries. Mothers of reproductive age (15-49 years) in each administration (n 143 258). In the pooled sample, a non-linear education gradient on mothers' overweight was found; each additional year of schooling increases the probability of being overweight up to the end of primary schooling, after which each additional year of schooling decreases the probability of overweight. Also, as access to diets high in animal fats and sweeteners increases over time, the curve's critical point moves to lower education levels, the detrimental positive effect of education diminishes, and both occur as the overall risk of overweight increases with greater access to harmful diets. Both hypotheses were supported. As the nutrition transition progresses, the education-overweight curve shifts steadily to a negative linear association with a higher average risk of overweight; and education, at increasingly lower levels, acts as a 'social vaccine' against increasing risk of overweight. These empirical patterns fit the general 'population education transition' curve hypothesis about how education's influences on health risks are contextualized across population transitions.

Dual energy X-ray absorptiometry body composition reference values of limbs and trunk from NHANES 1999–2004 with additional visualization methods

PubMed Central

Fan, Bo; Ng, Bennett K.; Shepherd, John A.

2017-01-01

Body Mass Index has traditionally been used as a measure of health, but Fat Mass Index (FMI) and Lean Mass Index (LMI) have been shown to be more predictive of mortality and health risk. Total body FMI and LMI reference curves have particularly been useful in quantifying sarcopenia and sarcopenic obesity. Research has shown regional composition has significant associations to health outcomes. We derived FMI and LMI reference curves of the regions of the body (leg, arm, and trunk) for 15,908 individuals in the 1999–2004 National Health and Nutrition Examination Survey data for each sex and ethnicity using the Lambda-Mu-Sigma (LMS) method and developed software to visualize this regional composition. These reference curves displayed differentiation between males and females during puberty and sharper limb LMI declines during late adulthood for males. For adults ages 30–50, females had 39%, 83%, and 47% larger arm, leg, and trunk FMI values than males, respectively. Males had 49%, 20%, and 15% higher regional LMI values than females for the arms, legs, and trunk respectively. The leg FMI and LMI of black females were 14% and 15% higher respectively than those of Hispanic and white females. White and Hispanic males had 37% higher trunk FMI values than black males. Hispanic females had 20% higher trunk FMI than white and black females. These data underscore the importance of accounting for sex and ethnicity in studies of regional composition. This study is the first to produce regional LMI and FMI reference tables and curves from the NHANES dataset. These reference curves provide a framework useful in studies and research involving sarcopenia, obesity, sarcopenic obesity, and other studies of compositional phenotypes. Further, the software tool we provide for visualizing regional composition will prove useful in monitoring progress in physical therapy, diets, or other attempts to attain healthier compositions. PMID:28346492

Circulating Tumor Cell Increase as a Biomarker of Disease Progression in Metastatic Castration-Resistant Prostate Cancer Patients with Low Baseline CTC Counts.

PubMed

Lorente, D; Olmos, D; Mateo, J; Dolling, D; Bianchini, D; Seed, G; Flohr, P; Crespo, M; Figueiredo, I; Miranda, S; Scher, H I; Terstappen, L W M M; de Bono, J S

2018-05-07

The development of treatment response and surrogate biomarkers for advanced prostate cancer care is an unmet clinical need. Patients with baseline circulating tumor cell counts (BLCTCs)<5/7.5 mL represent a good prognosis subgroup, but are non-evaluable for response assessment (decrease in CTCs). The aim of the study is to determine the value of any increase in CTCs (CTC Progression) as an indicator of progression in prostate cancer patients with low pre-treatment CTCs (<5). We performed a post-hoc analysis of patients with BLCTCs < 5 treated in the COU-AA-301 (abiraterone or placebo + prednisone) and IMMC-38 (chemotherapy) trials. The association of CTC Progression (increase in CTCs at 4, 8 or 12 weeks) with overall survival (OS) was evaluated in multivariable Cox regression models. Performance of survival models with and without CTC Progression was evaluated by calculating ROC curve AUCs and weighted c-indices. Overall, 511 patients with CTCs <5 (421 in COU-AA-301; 90 in IMMC-38) were selected; 212 (41.7%) had CTC Progression at 4, 8 or 12 weeks after treatment initiation. CTC Progression was associated with significantly worse OS (27.1 vs 15.1m; HR: 3.4 [95%CI:2.5-4.5; p < 0.001]); independent of baseline CTCs and established clinical variables. Adding CTC Progression to the OS model significantly improved ROC AUC (0.77 vs 0.66; p < 0.001). Models including CTC Progression had superior ROC AUC (0.77 vs 0.69; p < 0.001) and weighted c-index (0.750 vs 0.705; delta c-index: 0.045 [95%CI: 0.019-0.071]) values than those including CTC conversion (increase to CTCs ≥5). In COU-AA-301, the impact of CTC Progression was independent of treatment arm. Increasing CTCs during the first 12-weeks of treatment are independently associated with worse OS from advanced prostate cancer in patients with baseline CTCs < 5 treated with abiraterone or chemotherapy and improve models with established prognostic variables. These findings must be prospectively validated.

Long-term echocardiographic follow-up of untreated 2+ functional tricuspid regurgitation in patients undergoing mitral valve surgery†

PubMed Central

Kusajima, Kunio; Fujita, Tomoyuki; Hata, Hiroki; Shimahara, Yusuke; Miura, Sayaka; Kobayashi, Junjiro

2016-01-01

OBJECTIVES Concomitant tricuspid valve surgery with mitral valve surgery is recommended for patients with severe functional tricuspid regurgitation (TR). However, the treatment for 2+ TR (mild TR) remains controversial. Here, we evaluated the long-term results of untreated 2+ TR in patients undergoing mitral valve surgery. METHODS We retrospectively reviewed the records of 96 patients with untreated 2+ TR among 885 patients who underwent mitral valve surgery from 2003 to 2010. Exclusion criteria were tricuspid valve surgery (TVS), emergency surgery, primary TR and pacemaker lead through the tricuspid valve. We assessed survival and freedom from heart failure. The freedom from 3+ (moderate) or 4+ (severe) TR was investigated by echocardiographic data at pre- and postoperative week 1, then at 1, 3, 5, 7 and 10 postoperative years, which were compared with those in patients who had 2+ TR preoperatively and underwent concomitant TVS in the same period (n = 47). RESULTS The mean follow-up was 7.1 ± 2.7 years. There was no 30-day mortality. The survival rate was 97.5% at 5 years and 87.5% at 10 years. The independent risk factors for mortality were age (OR 1.2, P = 0.03) and left ventricular ejection fraction (OR 0.9, P = 0.03). Untreated 2+ TR improved transiently within the first postoperative year (P < 0.001), but progressed again in the mid- to long term. Freedom from ≥3+ TR was 64.2% at 5 years and 46.7% at 10 years, which was significantly lower than that from ≥3+ TR in patients who underwent concomitant TVS (P = 0.006). The independent risk factors for TR progression (≥3 + TR) were age (OR 1.1, P = 0.005), atrial fibrillation (OR 2.2, P = 0.04) and tricuspid annular diameter (TAD) index (mm/m2; OR 1.1, P = 0.02). Receiver operating characteristic curves showed that the optimal TAD index cut-off value was 21.0 for long-term survival [area under the curve (AUC) = 0.72] and 21.2 for TR progression (AUC = 0.64). CONCLUSIONS Although untreated, 2+ TR significantly improved after mitral valve surgery, it then progressed again in the mid- to long term. Therefore, concomitant TVS should be considered in patients with 2+ TR who have dilated tricuspid annulus or atrial fibrillation, if feasible. PMID:26993477

Prognostic value of circulating microRNAs in upper tract urinary carcinoma

PubMed Central

Ingelmo-Torres, Mercedes; Lozano, Juan José; Capitán, David; Alcaraz, Antonio; Mengual, Lourdes

2018-01-01

The identification of upper tract urinary carcinoma (UTUC) prognostic biomarkers is urgently needed to predict tumour progression. This study aimed to identify serum microRNAs (miRNAs) that may be useful as minimally invasive predictive biomarkers of tumour progression and survival in UTUC patients. To this end, 33 UTUC patients who underwent radical nephroureterectomy at the Hospital Clinic of Barcelona were prospectively included. Expression of 800 miRNAs was evaluated in serum samples from these patients using nCounter® miRNA Expression Assays. The study was divided into an initial discovery phase (n=12) and a validation phase (n=21). Cox regression analysis was used for survival analysis. The median follow-up (range) of the series was 42 months (9-100 months). In the discovery phase, 38 differentially expressed miRNAs were identified between progressing and non-progressing UTUC patients (p<0.05). Validation of these 38 miRNAs in an independent set of UTUC patients confirmed the differential expression in 18 of them (p<0.05). Cox Regression analysis showed miR-151b and pathological stage as significant prognostic factors for tumour progression (HR=0.33, p<0.001 and HR=2.62, p=0.006, respectively) and cancer specific survival (HR=0.25, p<0.001 and HR=3.98, p=0.003, respectively). Survival curves revealed that miR-151b is able to discriminate between two groups of UTUC patients with a highly significant different probability of tumour progression (p=0.006) and cancer specific survival (p=0.034). Although the data needs to be externally validated, miRNA analysis in serum appears to be a valuable prognostic tool in UTUC patients. Particularly, differential expression of miR-151b in serum may serve as a minimally invasive prognostic tool in UTUC. PMID:29682178

Prognostic value of circulating microRNAs in upper tract urinary carcinoma.

PubMed

Montalbo, Ruth; Izquierdo, Laura; Ingelmo-Torres, Mercedes; Lozano, Juan José; Capitán, David; Alcaraz, Antonio; Mengual, Lourdes

2018-03-30

The identification of upper tract urinary carcinoma (UTUC) prognostic biomarkers is urgently needed to predict tumour progression. This study aimed to identify serum microRNAs (miRNAs) that may be useful as minimally invasive predictive biomarkers of tumour progression and survival in UTUC patients. To this end, 33 UTUC patients who underwent radical nephroureterectomy at the Hospital Clinic of Barcelona were prospectively included. Expression of 800 miRNAs was evaluated in serum samples from these patients using nCounter® miRNA Expression Assays. The study was divided into an initial discovery phase (n=12) and a validation phase (n=21). Cox regression analysis was used for survival analysis. The median follow-up (range) of the series was 42 months (9-100 months). In the discovery phase, 38 differentially expressed miRNAs were identified between progressing and non-progressing UTUC patients (p<0.05). Validation of these 38 miRNAs in an independent set of UTUC patients confirmed the differential expression in 18 of them (p<0.05). Cox Regression analysis showed miR-151b and pathological stage as significant prognostic factors for tumour progression (HR=0.33, p<0.001 and HR=2.62, p=0.006, respectively) and cancer specific survival (HR=0.25, p<0.001 and HR=3.98, p=0.003, respectively). Survival curves revealed that miR-151b is able to discriminate between two groups of UTUC patients with a highly significant different probability of tumour progression (p=0.006) and cancer specific survival (p=0.034). Although the data needs to be externally validated, miRNA analysis in serum appears to be a valuable prognostic tool in UTUC patients. Particularly, differential expression of miR-151b in serum may serve as a minimally invasive prognostic tool in UTUC.

Predicting kidney disease progression in patients with acute kidney injury after cardiac surgery.

PubMed

Mizuguchi, K Annette; Huang, Chuan-Chin; Shempp, Ian; Wang, Justin; Shekar, Prem; Frendl, Gyorgy

2018-06-01

The study objective was to identify patients who are likely to develop progressive kidney dysfunction (acute kidney disease) before their hospital discharge after cardiac surgery, allowing targeted monitoring of kidney function in this at-risk group with periodic serum creatinine measurements. Risks of progression to acute kidney disease (a state in between acute kidney injury and chronic kidney disease) were modeled from acute kidney injury stages (Kidney Disease: Improving Global Outcomes) in patients undergoing cardiac surgery. A modified Poisson regression with robust error variance was used to evaluate the association between acute kidney injury stages and the development of acute kidney disease (defined as doubling of creatinine 2-4 weeks after surgery) in this observational study. Acute kidney disease occurred in 4.4% of patients with no preexisting kidney disease and 4.8% of patients with preexisting chronic kidney disease. Acute kidney injury predicted development of acute kidney disease in a graded manner in which higher stages of acute kidney injury predicted higher relative risk of progressive kidney disease (area under the receiver operator characteristic curve = 0.82). This correlation persisted regardless of baseline kidney function (P < .001). Of note, development of acute kidney disease was associated with higher mortality and need for renal replacement therapy. The degree of acute kidney injury can identify patients who will have a higher risk of progression to acute kidney disease. These patients may benefit from close follow-up of renal function because they are at risk of progressing to chronic kidney disease or end-stage renal disease. Copyright © 2018 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Fibulin-1 Predicts Disease Progression in Patients With Idiopathic Pulmonary Fibrosis

PubMed Central

Unger, Sofia; Corte, Tamera J.; Keller, Michael; Wolters, Paul J.; Richeldi, Luca; Cerri, Stefania; Prêle, Cecilia M.; Hansbro, Philip M.; Argraves, William Scott; Oliver, Rema A.; Oliver, Brian G.; Black, Judith L.; Burgess, Janette K.

2014-01-01

BACKGROUND: The underlying mechanisms of idiopathic pulmonary fibrosis (IPF) are unknown. This progressive disease has high mortality rates, and current models for prediction of mortality have limited value in identifying which patients will progress. We previously showed that the glycoprotein fibulin-1 is involved in enhanced proliferation and wound repair by mesenchymal cells and, thus, may contribute to lung fibrosis in IPF. METHODS: Serum, lung tissue, and lung function values were obtained from four independent locations (Sydney, NSW, and Perth, WA, Australia; San Francisco, CA; and Modena, Italy). Patients with IPF were followed for a minimum of 1 year and progression was defined as a significant decline in lung function or death. Primary parenchymal lung fibroblasts of 15 patients with and without IPF were cultured under nonstimulatory conditions. Fibulin-1 levels in serum, and secreted or deposited by fibroblasts, were measured by western blot and in lung tissue by immunohistochemistry. RESULTS: Serum fibulin-1 levels were increased in patients with IPF compared with subjects without lung disease (P = .006). Furthermore, tissue fibulin-1 levels were increased in patients with IPF (P = .02) and correlated negatively with lung function (r = −0.9, P < .05). Primary parenchymal fibroblasts from patients with IPF produced more fibulin-1 than those from subjects without IPF (P < .05). Finally, serum fibulin-1 levels at first blood draw predicted disease progression in IPF within 1 year (area under the curve , 0.71; 95% CI, 0.57-0.86; P = .012). CONCLUSIONS: Fibulin-1 is a novel potential biomarker for disease progression in IPF and raises the possibility that it could be used as a target for the development of new treatments. PMID:24832167

The effects of AST-120 on chronic kidney disease progression in the United States of America: a post hoc subgroup analysis of randomized controlled trials.

PubMed

Schulman, Gerald; Berl, Tomas; Beck, Gerald J; Remuzzi, Giuseppe; Ritz, Eberhard; Shimizu, Miho; Shobu, Yuko; Kikuchi, Mami

2016-09-30

The orally administered spherical carbon adsorbent AST-120 is used on-label in Asian countries to slow renal disease progression in patients with progressive chronic kidney disease (CKD). Recently, two multinational, randomized, double-blind, placebo-controlled, phase 3 trials (Evaluating Prevention of Progression in Chronic Kidney Disease [EPPIC] trials) examined AST-120's efficacy in slowing CKD progression. This study assessed the efficacy of AST-120 in the subgroup of patients from the United States of America (USA) in the EPPIC trials. In the EPPIC trials, 2035 patients with moderate to severe CKD were studied, of which 583 were from the USA. The patients were randomly assigned to two groups of equal size that were treated with AST-120 or placebo (9 g/day). The primary end point was a composite of dialysis initiation, kidney transplantation, or serum creatinine doubling. The Kaplan-Meier curve for the time to achieve the primary end point in the placebo-treated patients from the USA was similar to that projected before the study. The per protocol subgroup analysis of the population from the USA which included patients with compliance rates of ≥67 % revealed a significant difference between the treatment groups in the time to achieve the primary end point (Hazard Ratio, 0.74; 95 % Confidence Interval, 0.56-0.97). This post hoc subgroup analysis of EPPIC study data suggests that treatment with AST-120 might delay the time to primary end point in CKD patients from the USA. A further randomized controlled trial in progressive CKD patients in the USA is necessary to confirm the beneficial effect of adding AST-120 to standard therapy regimens. ClinicalTrials.gov NCT00500682 ; NCT00501046 .

Fibulin-1 predicts disease progression in patients with idiopathic pulmonary fibrosis.

PubMed

Jaffar, Jade; Unger, Sofia; Corte, Tamera J; Keller, Michael; Wolters, Paul J; Richeldi, Luca; Cerri, Stefania; Prêle, Cecilia M; Hansbro, Philip M; Argraves, William Scott; Oliver, Rema A; Oliver, Brian G; Black, Judith L; Burgess, Janette K

2014-10-01

The underlying mechanisms of idiopathic pulmonary fibrosis (IPF) are unknown. This progressive disease has high mortality rates, and current models for prediction of mortality have limited value in identifying which patients will progress. We previously showed that the glycoprotein fibulin-1 is involved in enhanced proliferation and wound repair by mesenchymal cells and, thus, may contribute to lung fibrosis in IPF. Serum, lung tissue, and lung function values were obtained from four independent locations (Sydney, NSW, and Perth, WA, Australia; San Francisco, CA; and Modena, Italy). Patients with IPF were followed for a minimum of 1 year and progression was defined as a significant decline in lung function or death. Primary parenchymal lung fibroblasts of 15 patients with and without IPF were cultured under nonstimulatory conditions. Fibulin-1 levels in serum, and secreted or deposited by fibroblasts, were measured by western blot and in lung tissue by immunohistochemistry. Serum fibulin-1 levels were increased in patients with IPF compared with subjects without lung disease (P = .006). Furthermore, tissue fibulin-1 levels were increased in patients with IPF (P = .02) and correlated negatively with lung function (r = -0.9, P < .05). Primary parenchymal fibroblasts from patients with IPF produced more fibulin-1 than those from subjects without IPF (P < .05). Finally, serum fibulin-1 levels at first blood draw predicted disease progression in IPF within 1 year (area under the curve , 0.71; 95% CI, 0.57-0.86; P = .012). Fibulin-1 is a novel potential biomarker for disease progression in IPF and raises the possibility that it could be used as a target for the development of new treatments.

Risk factors for the prognosis of pediatric medulloblastoma: a retrospective analysis of 40 cases.

PubMed

Yu, Jianzhong; Zhao, Rui; Shi, Wei; Li, Hao

2017-05-01

In this study, we evaluated the association of molecular subtypes, clinical characteristics and pathological types with the prognosis of patients with medulloblastoma. We analyzed forty patients with medulloblastoma who underwent surgical resection at our center between January 2004 and June 2014. Risk factors associated with survival, disease progression and recurrence were analyzed with a univariate Cox regression analysis, and the identified significant risk factors were further analyzed by Kaplan-Meier survival curves. Factors associated with overall survival included M stage (p=0.014), calcification (p=0.012), postoperative treatment, postoperative Karnofsky Performance Scale (KPS) score (p=0.015), and molecular subtype (p=0.005 for WNT and p=0.008 for SHH). Number of symptoms (p=0.029), M stage (p<0.001), and postoperative radiotherapy (p=0.033) were associated with disease progression. Patients with the WNT or SHH subtype had better survival outcomes than patients with non-WNT/SHH subtypes. Risk factors for disease progression-free survival were symptoms >2 and ≥M1 stage without postoperative radiotherapy. The risk of recurrence increased with advanced M stage. Protective factors for recurrence included M0 stage and a combination of chemotherapy and radiotherapy. We identified the risk factors associated with survival, disease progression and recurrence of medulloblastoma patients. This information is helpful for understanding the prognostic factors related to medulloblastoma.

Objective diagnosis of arrested labor on transperineal ultrasound.

PubMed

Nishimura, Kazuaki; Yoshimura, Kazuaki; Kubo, Tatsuhiko; Hachisuga, Toru

2016-07-01

Recent developments in transperineal ultrasound imaging of the pelvis have prompted trials to objectively evaluate labor progression for labor management. We evaluated the accuracy of transperineal ultrasound in diagnosing arrest of labor. Transperineal ultrasound and digital pelvic examinations were performed simultaneously in 63 term laboring patients (singleton fetuses in cephalic presentation). We analyzed a total of 216 ultrasound images (Sonography Volume Computer Aided Display Labor [Sono VCAD Labor®] installed in Voluson E8 ultrasound). We examined the correlation between the three ultrasound parameters head direction (HD), progression distance (PD), and progression angle (PA), and digital pelvic examination findings during labor in a transvaginal delivery group and an arrested labor group. The coefficient of correlations between HD/PD/PA and cervical dilation/fetal station were 0.667/0.657/0.706 and 0.667/0.751/0.803, respectively. The three parameters had strong correlations with digital pelvic examination (P < 0.05). In the 11 cases (17%) of cesarean section due to arrested labor, the position of the fetal head was visually unchanged on sequential ultrasound images. According to receiver operating characteristic curves, the significant cut-offs for HD, PD, and PA for arrested labor were 105° (P = 0.048), 35 mm (P = 0.048), and 120° (P = 0.001), respectively. Transperineal ultrasound imaging is helpful for objective evaluation of labor progression and the diagnosis of arrested labor. © 2016 Japan Society of Obstetrics and Gynecology.

Analysis of the learning curve for transurethral resection of the prostate. Is there any influence of musical instrument and video game skills on surgical performance?

PubMed

Yamaçake, Kleiton Gabriel Ribeiro; Nakano, Elcio Tadashi; Soares, Iva Barbosa; Cordeiro, Paulo; Srougi, Miguel; Antunes, Alberto Azoubel

2015-09-01

To evaluate the learning curve for transurethral resection of the prostate (TURP) among urology residents and study the impact of video game and musical instrument playing abilities on its performance. A prospective study was performed from July 2009 to January 2013 with patients submitted to TURP for benign prostatic hyperplasia. Fourteen residents operated on 324 patients. The following parameters were analyzed: age, prostate-specific antigen levels, prostate weight on ultrasound, pre- and postoperative serum sodium and hemoglobin levels, weight of resected tissue, operation time, speed of resection, and incidence of capsular lesions. Gender, handedness, and prior musical instrument and video game playing experience were recorded using survey responses. The mean resection speed in the first 10 procedures was 0.36 g/min and reached a mean of 0.51 g/min after the 20(th) procedure. The incidence of capsular lesions decreased progressively. The operation time decreased progressively for each subgroup regardless of the difference in the weight of tissue resected. Those experienced in playing video games presented superior resection speed (0.45 g/min) when compared with the novice (0.35 g/min) and intermediate (0.38 g/min) groups (p=0.112). Musical instrument playing abilities did not affect the surgical performance. Speed of resection, weight of resected tissue, and percentage of resected tissue improve significantly and the incidence of capsular lesions reduces after the performance of 10 TURP procedures. Experience in playing video games or musical instruments does not have a significant effect on outcomes.

Intact protein analysis of ubiquitin in cerebrospinal fluid by multiple reaction monitoring reveals differences in Alzheimer's disease and frontotemporal lobar degeneration.

PubMed

Oeckl, Patrick; Steinacker, Petra; von Arnim, Christine A F; Straub, Sarah; Nagl, Magdalena; Feneberg, Emily; Weishaupt, Jochen H; Ludolph, Albert C; Otto, Markus

2014-11-07

The impairment of the ubiquitin-proteasome system (UPS) is thought to be an early event in neurodegeneration, and monitoring UPS alterations might serve as a disease biomarker. Our aim was to establish an alternate method to antibody-based assays for the selective measurement of free monoubiquitin in cerebrospinal fluid (CSF). Free monoubiquitin was measured with liquid chromatography-multiple reaction monitoring mass spectrometry (LC-MS/MS) in CSF of patients with Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), behavioral variant of frontotemporal dementia (bvFTD), Creutzfeldt-Jakob disease (CJD), Parkinson's disease (PD), primary progressive aphasia (PPA), and progressive supranuclear palsy (PSP). The LC-MS/MS method showed excellent intra- and interassay precision (4.4-7.4% and 4.9-10.3%) and accuracy (100-107% and 100-106%). CSF ubiquitin concentration was increased compared with that of controls (33.0 ± 9.7 ng/mL) in AD (47.5 ± 13.1 ng/mL, p < 0.05) and CJD patients (171.5 ± 103.5 ng/mL, p < 0.001) but not in other neurodegenerative diseases. Receiver operating characteristic curve (ROC) analysis of AD vs control patients revealed an area under the curve (AUC) of 0.832, and the specificity and sensitivity were 75 and 75%, respectively. ROC analysis of AD and FTLD patients yielded an AUC of 0.776, and the specificity and sensitivity were 53 and 100%, respectively. In conclusion, our LC-MS/MS method may facilitate ubiquitin determination to a broader community and might help to discriminate AD, CJD, and FTLD patients.

Training on N.O.T.E.S.: from history we learn.

PubMed

Al-Akash, M; Boyle, E; Tanner, W A

2009-06-01

Surgical errors occurring early in the learning curve of laparoscopic surgery providers delayed the uptake and progress of minimally invasive surgery (MIS) for years. This taught us a valuable lesson; innovations in surgical techniques should not be rapidly implemented until all aspects including applicability, feasibility and safety have been fully tested. In 2005, the Natural Orifice Surgery Consortium for Assessment and Research (NOSCAR) published a white paper highlighting the barriers to NOTES development and identifying key elements for its progress. One of these elements is the training of future providers. Proficiency-based, virtual reality simulation will offer a feasible alternative to animal testing once the safety and efficacy parameters of NOTES are established. Recent advances in imaging including computed tomography (CT) scanning, magnetic resonance imaging (MRI) scanning, and ultrasound (US) scanning can offer improved image registration and real-time tracking. Combining these advanced imaging technologies with the newly designed virtual reality simulators will result in a fully comprehensive simulation curriculum which will offer a unique facility for future NOTES providers to train anytime, anywhere, and as much as they need to in order to achieve the pre-set proficiency levels for a variety of NOTES procedures. Furthermore they will incorporate patient-specific anatomical models obtained from patient imaging and uploaded onto the simulator to ensure face reliability and validity assurance. Training in a clean, safe environment with proximate feedback and performance analysis will help accelerate the learning curve and therefore improve patients' safety and outcomes in order to maximize the benefits of innovative access procedures such as NOTES.

Scoliosis in Rett Syndrome: Progression, Comorbidities, and Predictors.

PubMed

Killian, John T; Lane, Jane B; Lee, Hye-Seung; Skinner, Steve A; Kaufmann, Walter E; Glaze, Daniel G; Neul, Jeffrey L; Percy, Alan K

2017-05-01

Scoliosis is prominent in Rett syndrome (RTT). Following the prior report from the US Natural History Study, the onset and progression of severe scoliosis (≥40° Cobb angle) and surgery were examined regarding functional capabilities and specific genotypes, addressing the hypothesis that abnormal muscle tone, poor oral feeding, puberty, and delays or absence of sitting balance and ambulation may be responsible for greater risk in RTT. The multicenter RTT Natural History Study gathered longitudinal data for classic RTT, including mutation type, scoliosis, muscle tone, sitting, ambulation, hand function, and feeding. Cox regression models were used to examine the association between scoliosis and functional characteristics. All analyses utilized SAS 9.4; two-sided P values of <0.05 were considered significant. A total of 913 females with classic RTT were included. Scoliosis frequency and severity increased with age. Severe scoliosis was found in 251 participants (27%), 113 of whom developed severe scoliosis during the follow-up assessments; 168 (18%) had surgical correction. Severe MECP2 mutations (R106W, R168X, R255X, R270X, and large deletions) showed a higher proportion of scoliosis. Individuals developing severe scoliosis or requiring surgery were less likely to sit, ambulate, or use their hands and were more likely to have begun puberty. Significant differences were absent for epilepsy rates, sleep problems, or constipation. Scoliosis requires vigilance regarding the risk factors noted, particularly specific mutations and the role of puberty and motor abilities. Bracing is recommended for moderate curves and surgery for severe curves in accordance with published guidelines for scoliosis management. Copyright © 2017 Elsevier Inc. All rights reserved.

Integrative "omic" analysis of experimental bacteremia identifies a metabolic signature that distinguishes human sepsis from systemic inflammatory response syndromes.

PubMed

Langley, Raymond J; Tipper, Jennifer L; Bruse, Shannon; Baron, Rebecca M; Tsalik, Ephraim L; Huntley, James; Rogers, Angela J; Jaramillo, Richard J; O'Donnell, Denise; Mega, William M; Keaton, Mignon; Kensicki, Elizabeth; Gazourian, Lee; Fredenburgh, Laura E; Massaro, Anthony F; Otero, Ronny M; Fowler, Vance G; Rivers, Emanuel P; Woods, Chris W; Kingsmore, Stephen F; Sopori, Mohan L; Perrella, Mark A; Choi, Augustine M K; Harrod, Kevin S

2014-08-15

Sepsis is a leading cause of morbidity and mortality. Currently, early diagnosis and the progression of the disease are difficult to make. The integration of metabolomic and transcriptomic data in a primate model of sepsis may provide a novel molecular signature of clinical sepsis. To develop a biomarker panel to characterize sepsis in primates and ascertain its relevance to early diagnosis and progression of human sepsis. Intravenous inoculation of Macaca fascicularis with Escherichia coli produced mild to severe sepsis, lung injury, and death. Plasma samples were obtained before and after 1, 3, and 5 days of E. coli challenge and at the time of killing. At necropsy, blood, lung, kidney, and spleen samples were collected. An integrative analysis of the metabolomic and transcriptomic datasets was performed to identify a panel of sepsis biomarkers. The extent of E. coli invasion, respiratory distress, lethargy, and mortality was dependent on the bacterial dose. Metabolomic and transcriptomic changes characterized severe infections and death, and indicated impaired mitochondrial, peroxisomal, and liver functions. Analysis of the pulmonary transcriptome and plasma metabolome suggested impaired fatty acid catabolism regulated by peroxisome-proliferator activated receptor signaling. A representative four-metabolite model effectively diagnosed sepsis in primates (area under the curve, 0.966) and in two human sepsis cohorts (area under the curve, 0.78 and 0.82). A model of sepsis based on reciprocal metabolomic and transcriptomic data was developed in primates and validated in two human patient cohorts. It is anticipated that the identified parameters will facilitate early diagnosis and management of sepsis.

Reconstruction for proton computed tomography by tracing proton trajectories: A Monte Carlo study

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

Li Tianfang; Liang Zhengrong; Singanallur, Jayalakshmi V.

Proton computed tomography (pCT) has been explored in the past decades because of its unique imaging characteristics, low radiation dose, and its possible use for treatment planning and on-line target localization in proton therapy. However, reconstruction of pCT images is challenging because the proton path within the object to be imaged is statistically affected by multiple Coulomb scattering. In this paper, we employ GEANT4-based Monte Carlo simulations of the two-dimensional pCT reconstruction of an elliptical phantom to investigate the possible use of the algebraic reconstruction technique (ART) with three different path-estimation methods for pCT reconstruction. The first method assumes amore » straight-line path (SLP) connecting the proton entry and exit positions, the second method adapts the most-likely path (MLP) theoretically determined for a uniform medium, and the third method employs a cubic spline path (CSP). The ART reconstructions showed progressive improvement of spatial resolution when going from the SLP [2 line pairs (lp) cm{sup -1}] to the curved CSP and MLP path estimates (5 lp cm{sup -1}). The MLP-based ART algorithm had the fastest convergence and smallest residual error of all three estimates. This work demonstrates the advantage of tracking curved proton paths in conjunction with the ART algorithm and curved path estimates.« less

KINETICS OF THE ACTION OF AMPICILLIN ON ESCHERICHIA COLI

PubMed Central

Seligman, Stephen J.; Hewitt, William L.

1963-01-01

Seligman, Stephen J. (University of California, Los Angeles) and William L. Hewitt. Kinetics of the action of ampicillin on Escherichia coli. J. Bacteriol. 85:1160–1164. 1963.—The curve of the number of viable Escherichia coli after exposure to ampicillin can be divided into three phases: a lag phase, a rapid bactericidal phase, and a slow bactericidal phase. Some of the variables affecting the magnitude of the first two of these phases were investigated. Progressive lowering of drug concentration resulted in prolongation of the lag phase and decrease in slope and extent of the rapid bactericidal phase. The production of elongated gram-negative forms and the emergence of a mutant with increased penicillinase activity complicated interpretation of the lower dose curves. With sufficient drug concentration, the length of the lag phase and the slope of the rapid bactericidal curve were independent of the size of inoculum up to 108 organisms. Varying pH revealed that maximal activity, as measured by the shortest lag phase and steepest slope of the rapid bactericidal phase, was present at slightly acid pH levels. Increasing pH resulted principally in prolongation of lag phase. With greater acidity, decrease in slope of the rapid bactericidal phase was more prominent. Cultures studied under conditions of lessened metabolic activity exhibited prolonged lag phase and decreased slope and extent of rapid bactericidal phase. PMID:14044010

Predictive value of the complement system for sepsis-induced disseminated intravascular coagulation in septic patients in emergency department.

PubMed

Zhao, Xin; Chen, Yun-Xia; Li, Chun-Sheng

2015-04-01

To investigate changes in circulating complement component C3, membrane attack complex (MAC), and mannose-binding lectin (MBL) in patients with sepsis-induced disseminated intravascular coagulation (DIC). Adult septic patients admitted to the emergency department (ED) of Beijing Chao-Yang Hospital were enrolled. A DIC score of 5 or higher was considered sepsis-induced DIC. Circulating C3, MAC, and MBL levels were detected on ED arrival and compared between patients with and without DIC. The predictive value of C3, MAC, and MBL for sepsis-induced DIC at ED arrival and development of DIC after admission were assessed by receiver operating characteristic curve and logistic regression. We enrolled 267 septic patients between February and December 2013. Complement 3, MAC, and MBL were higher in the DIC group (P < .01). Membrane attack complex was the independent predictor of sepsis-induced DIC. The area under the curve of MAC in predicting sepsis-induced DIC was 0.793. During hospitalization, 25 patients without DIC at enrollment developed DIC. Membrane attack complex and Sequential Organ Failure Assessment independently predicted progress to DIC. The area under the curve of MAC was 0.741. Complement 3, MAC, and MBL were significantly increased in septic patients with DIC. Membrane attack complex independently predicted sepsis-induced DIC and development of DIC after ED admission. Copyright © 2014 Elsevier Inc. All rights reserved.

Spontaneous labor curves in women with pregnancies complicated by diabetes.

PubMed

Timofeev, Julia; Huang, Chun-Chih; Singh, Jasbir; Driggers, Rita W; Landy, Helain J

2012-01-01

To test the hypothesis that the first stage of labor will be longer in nulliparous and multiparous women with diabetes compared to non-diabetic counterparts. A retrospective analysis was performed from 228,668 deliveries between 2002-2008 from the Consortium of Safe Labor (National Institute of Child Health and Human Development, National Institutes of Health). Patients with spontaneous onset of labor from 37 0/7-41 6/7 weeks gestation were included (71,282) and classified as nulliparous or multiparous. Pregnancies were further subdivided regarding presence of preexisting diabetes (preDM) or gestational diabetes (GDM) and normal controls. Labor curves were created matching for body mass index (BMI) and neonatal birth weight. Statistical analysis was performed on descriptive variables using χ(2) with significance designated as p < 0.05. Among nulliparous patients, there were 118 women with preDM and 475 women with GDM; 25,771 patients served as normal controls. Among multiparous women, there were 311 with preDM, 1,079 with GDM and 43,528 in the control group. Although differences in dilatation rates were observed in nulliparous and multiparous women with and without diabetes, labor progression was similar between the subgroups when matched for maternal BMI and birth weight. Labor curves of women with preDM and GDM approximate those of non-diabetics, regardless of BMI, birth weight, or parity.

A questionnaire approach to measuring the relative reinforcing efficacy of snack foods

PubMed Central

Epstein, Leonard H.; Dearing, Kelly K.; Roba, Lora G.

2010-01-01

Behavioral choice theory and laboratory choice paradigms can provide a framework to understand the reinforcing efficacy or reinforcing value of food. Reinforcing efficacy is measured in the laboratory by assessing how much effort one will engage in to gain access to food as the amount of work progressively increases. However, this method to establish demand curves as estimates of reinforcer efficacy is time consuming and limits the number of reinforcers that can be tested. The general aim of this study was to compare the reinforcing efficacy of snack foods using a behavioral task that requires subjects to respond to gain access to portions of food (LAB task) with a questionnaire version of a purchasing task designed to determine demand curves (QUES task) in nonobese and obese adults (n = 24). Results showed correlations between the maximal amount of money that individuals were willing to spend for food (QUES Omax) and the maximal amount of responses made on the highest reinforcement schedule completed (LAB Omax) (r = 0.45, p < 0.05), and between BMI and the LAB Omax (r = 0.43, p < 0.05) and the QUES Omax (r = 0.52, p < 0.05). The study suggests the questionnaire provides valid measures of reinforcing efficacy that can be used in place of or in conjunction with traditional laboratory paradigms to establish demand curves that describe the behavioral maintaining properties of food. PMID:20188288

Chemosensitivity testing of human tumors using a microplate adenosine triphosphate luminescence assay: clinical correlation for cisplatin resistance of ovarian carcinoma.

PubMed

Andreotti, P E; Cree, I A; Kurbacher, C M; Hartmann, D M; Linder, D; Harel, G; Gleiberman, I; Caruso, P A; Ricks, S H; Untch, M

1995-11-15

An ATP luminescence assay (TCA 100) was used to measure chemotherapeutic drug sensitivity and resistance of dissociated tumor cells cultured for 6 days in serum-free medium and 96-well polypropylene microplates. Studies were performed with surgical, needle biopsy, pleural, or ascitic fluid specimens using 10,000-20,000 cells/well. ATP measurements were used to determine tumor growth inhibition. Single agent and drug combinations were evaluated using the area under the curve and 50% inhibitory concentration (IC50) results for a series of test drug concentrations. The ATP luminometry method had high sensitivity, linearity, and precision for measuring the activity of single agents and drug combinations. Assay reproducibility was high with intraassay and interassay coefficients of variation of 10-15% for percentage of tumor growth inhibition, 5-10% for area under curve, and 15-20% for IC50 results. Good correlation (r = 0.93) between the area under the curve, and IC50 results was observed. Cytological studies with 124 specimens demonstrated selective growth of malignant cells in the serum-free culture system. Studies with malignant and benign specimens also showed selective growth of malignant cells in the serum-free medium used for assay. The assay had a success rate of 87% based on criteria for specimen histopathology, magnitude of cell growth, and dose-response drug activity. Cisplatin results for ovarian carcinoma are presented for 81 specimens from 70 untreated patients and 33 specimens from 30 refractory patients. A model for interpretation of these results based on the correlation of clinical response with the area under the curve and IC50 results indicates that the assay has > 90% accuracy for cisplatin resistance of ovarian carcinoma. Additional studies are in progress to evaluate the clinical efficacy of this assay.

Gross Motor Function Measure Evolution Ratio: Use as a Control for Natural Progression in Cerebral Palsy.

PubMed

Marois, Pierre; Marois, Mikael; Pouliot-Laforte, Annie; Vanasse, Michel; Lambert, Jean; Ballaz, Laurent

2016-05-01

To develop a new way to interpret Gross Motor Function Measure (GMFM-66) score improvement in studies conducted without control groups in children with cerebral palsy (CP). The curves, which describe the pattern of motor development according to the children's Gross Motor Function Classification System level, were used as historical control to define the GMFM-66 expected natural evolution in children with CP. These curves have been modeled and generalized to fit the curve to particular children characteristics. Research center. Not applicable. Not applicable. Not applicable. Assuming that the GMFM-66 score evolution followed the shape of the Rosenbaum curves, by taking into account the age and GMFM-66 score of children, the expected natural evolution of the GMFM-66 score was predicted for any group of children with CP who were <8 years old. Because the expected natural evolution could be predicted for a specific group of children with CP, the efficacy of a treatment could be determined by comparing the GMFM-66 score evolution measured before and after treatment with the expected natural evolution for the same period. A new index, the Gross Motor Function Measure Evolution Ratio, was defined as follows: Gross Motor Function Measure Evolution Ratio=measured GMFM-66 score change/expected natural evolution. For practical or ethical reasons, it is almost impossible to use control groups in studies evaluating effectiveness of many therapeutic modalities. The Gross Motor Function Measure Evolution Ratio gives the opportunity to take into account the expected natural evolution of the gross motor function of children with CP, which is essential to accurately interpret the therapy effect on the GMFM-66. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Modeling the adiabatic connection in H2.

PubMed

Peach, Michael J G; Teale, Andrew M; Tozer, David J

2007-06-28

Full configuration interaction (FCI) data are used to quantify the accuracy of approximate adiabatic connection (AC) forms in describing the ground state potential energy curve of H2, within spin-restricted density functional theory (DFT). For each internuclear separation R, accurate properties of the AC are determined from large basis set FCI calculations. The parameters in the approximate AC form are then determined so as to reproduce these FCI values exactly, yielding an exchange-correlation energy expressed entirely in terms of FCI-derived quantities. This is combined with other FCI-derived energy components to give the total electronic energy; comparison with the FCI energy quantifies the accuracy of the AC form. Initial calculations focus on a [1/1]-Padé-based form. The potential energy curve determined using the procedure is a notable improvement over those from existing DFT functionals. The accuracy near equilibrium is quantified by calculating the bond length and vibrational wave numbers; errors in the latter are below 0.5%. The molecule dissociates correctly, which can be traced to the use of virtual orbital eigenvalues in the slope in the noninteracting limit, capturing static correlation. At intermediate R, the potential energy curve exhibits an unphysical barrier, similar to that noted previously using the random phase approximation. Alternative forms of the AC are also considered, paying attention to size extensivity and the behavior in the strong-interaction limit; none provide an accurate potential energy curve for all R, although good accuracy can be achieved near equilibrium. The study demonstrates how data from correlated ab initio calculations can provide valuable information about AC forms and highlight areas where further theoretical progress is required.

On the importance of accounting for competing risks in pediatric cancer trials designed to delay or avoid radiotherapy: I. Basic concepts and first analyses.

PubMed

Tai, Bee-Choo; Grundy, Richard G; Machin, David

2010-04-01

In trials designed to delay or avoid irradiation among children with malignant brain tumor, although irradiation after disease progression is an important event, patients who have disease progression may decline radiotherapy (RT), or those without disease progression may opt for elective RT. To accurately describe the cumulative need for RT in such instances, it is crucial to account for these distinct events and to evaluate how each contributes to the delay or advancement of irradiation via a competing risks analysis. We describe the summary of competing events in such trials using competing risks methods based on cumulative incidence functions and Gray's test. The results obtained are contrasted with standard survival methods based on Kaplan-Meier curves, cause-specific hazard functions and log-rank test. The Kaplan-Meier method overestimates all event-specific rates. The cause-specific hazard analysis showed reduction in hazards for all events (A: RT after progression; B: no RT after progression; C: elective RT) among children with ependymoma. For event A, a higher cumulative incidence was reported for ependymoma. Although Gray's test failed to detect any difference (p = 0.331) between histologic subtypes, the log-rank test suggested marginal evidence (p = 0.057). Similarly, for event C, the log-rank test found stronger evidence of reduction in hazard among those with ependymoma (p = 0.005) as compared with Gray's test (p = 0.086). To evaluate treatment differences, failing to account for competing risks using appropriate methodology may lead to incorrect interpretations.

Association between progression-free survival and health-related quality of life in oncology: a systematic review protocol.

PubMed

Kovic, Bruno; Guyatt, Gordon; Brundage, Michael; Thabane, Lehana; Bhatnagar, Neera; Xie, Feng

2016-09-02

There is an increasing number of new oncology drugs being studied, approved and put into clinical practice based on improvement in progression-free survival, when no overall survival benefits exist. In oncology, the association between progression-free survival and health-related quality of life is currently unknown, despite its importance for patients with cancer, and the unverified assumption that longer progression-free survival indicates improved health-related quality of life. Thus far, only 1 study has investigated this association, providing insufficient evidence and inconclusive results. The objective of this study protocol is to provide increased transparency in supporting a systematic summary of the evidence bearing on this association in oncology. Using the OVID platform in MEDLINE, Embase and Cochrane databases, we will conduct a systematic review of randomised controlled human trials addressing oncology issues published starting in 2000. A team of reviewers will, in pairs, independently screen and abstract data using standardised, pilot-tested forms. We will employ numerical integration to calculate mean incremental area under the curve between treatment groups in studies for health-related quality of life, along with total related error estimates, and a 95% CI around incremental area. To describe the progression-free survival to health-related quality of life association, we will construct a scatterplot for incremental health-related quality of life versus incremental progression-free survival. To estimate the association, we will use a weighted simple regression approach, comparing mean incremental health-related quality of life with either median incremental progression-free survival time or the progression-free survival HR, in the absence of overall survival benefit. Identifying direction and magnitude of association between progression-free survival and health-related quality of life is critically important in interpreting results of oncology trials. Systematic evidence produced from our study will contribute to improvement of patient care and practice of evidence-based medicine in oncology. 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/

Combined Diffusion Tensor Imaging and Apparent Transverse Relaxation Rate Differentiate Parkinson Disease and Atypical Parkinsonism.

PubMed

Du, G; Lewis, M M; Kanekar, S; Sterling, N W; He, L; Kong, L; Li, R; Huang, X

2017-05-01

Both diffusion tensor imaging and the apparent transverse relaxation rate have shown promise in differentiating Parkinson disease from atypical parkinsonism (particularly multiple system atrophy and progressive supranuclear palsy). The objective of the study was to assess the ability of DTI, the apparent transverse relaxation rate, and their combination for differentiating Parkinson disease, multiple system atrophy, progressive supranuclear palsy, and controls. A total of 106 subjects (36 controls, 35 patients with Parkinson disease, 16 with multiple system atrophy, and 19 with progressive supranuclear palsy) were included. DTI and the apparent transverse relaxation rate measures from the striatal, midbrain, limbic, and cerebellar regions were obtained and compared among groups. The discrimination performance of DTI and the apparent transverse relaxation rate among groups was assessed by using Elastic-Net machine learning and receiver operating characteristic curve analysis. Compared with controls, patients with Parkinson disease showed significant apparent transverse relaxation rate differences in the red nucleus. Compared to those with Parkinson disease, patients with both multiple system atrophy and progressive supranuclear palsy showed more widespread changes, extending from the midbrain to striatal and cerebellar structures. The pattern of changes, however, was different between the 2 groups. For instance, patients with multiple system atrophy showed decreased fractional anisotropy and an increased apparent transverse relaxation rate in the subthalamic nucleus, whereas patients with progressive supranuclear palsy showed an increased mean diffusivity in the hippocampus. Combined, DTI and the apparent transverse relaxation rate were significantly better than DTI or the apparent transverse relaxation rate alone in separating controls from those with Parkinson disease/multiple system atrophy/progressive supranuclear palsy; controls from those with Parkinson disease; those with Parkinson disease from those with multiple system atrophy/progressive supranuclear palsy; and those with Parkinson disease from those with multiple system atrophy; but not those with Parkinson disease from those with progressive supranuclear palsy, or those with multiple system atrophy from those with progressive supranuclear palsy. DTI and the apparent transverse relaxation rate provide different but complementary information for different parkinsonisms. Combined DTI and apparent transverse relaxation rate may be a superior marker for the differential diagnosis of parkinsonisms. © 2017 by American Journal of Neuroradiology.

Glaucoma Progression and its Relationship with Corrected and Uncorrected Intraocular Pressure in Eyes with History of Refractive Corneal Surgery.

PubMed

Kwon, Junki; Sung, Kyung Rim; Jo, Jaehyuck; Yang, Sung Ho

2018-04-20

To investigate glaucoma progression and its relationship with corrected and uncorrected intraocular pressure (IOP) in patients with a history of refractive corneal surgery (RCS). Totally, 56 eyes of 56 primary open-angle glaucoma patients who had a history of RCS were included. Mean keratometry and central corneal thickness were measured at the time of glaucoma diagnosis. Three IOP measurements, i.e., uncorrected IOP ( UC IOP) and corrected IOP calculated by applying the Kohlhaas ( CK IOP) and Ehlers ( CE IOP) formulas, were used. Participants were categorized into two groups (low-teen [<15 mmHg] and high-teen [≥15 mmHg] groups) according to the mean follow-up IOP, in each of the three IOP measurements. Glaucoma progression was determined based on either structurally or functionally by stereoscopic optic disc/retinal nerve fiber layer photographs or visual field tests. Kaplan-Meier survival curves were compared between the low-teens group and high-teens group for each IOP measurement. Risk factors for glaucoma progression, including uncorrected and corrected IOP measurements, were analyzed using a Cox proportional-hazards model. Among total eyes, glaucoma progression was found in 19 (34%) eyes during 4.3 years of mean follow-up period. Individual values of uncorrected IOP and corrected IOP showed significant differences (p < 0.001). Incidence of glaucoma progression was higher in high-teens group than in low-teens group by corrected IOP values (both Kohlhaas and Ehlers, p = 0.006, 0.003), but not by uncorrected IOP values (p = 0.749). The cumulative probability of glaucoma progression was significantly greater in the high-teens group than in the low-teens group using the Elhers formula determined by Kaplan-Meier analysis (p = 0.030). For glaucoma eyes with history of RCS, high-teen group by corrected mean follow-up IOP showed more glaucoma progression than low-teen group. More intensive IOP-lowering treatment will be required for patient with high-teen follow-up corrected IOP to prevent glaucoma progression.

Previous Bladder Cancer History in Patients with High-Risk, Non-muscle-invasive Bladder Cancer Correlates with Recurrence and Progression: Implications of Natural History.

PubMed

Mitrakas, Lampros P; Zachos, Ioannis V; Tzortzis, Vassileios P; Gravas, Stavros A; Rouka, Erasmia C; Dimitropoulos, Konstantinos I; Vandoros, Gerasimos P; Karatzas, Anastasios D; Melekos, Michael D; Papavassiliou, Athanasios G

2015-07-01

The purpose of this study was to assess the correlation of previous bladder cancer history with the recurrence and progression of patients with high-risk non-muscle-invasive bladder cancer treated with adjuvant Bacillus Calmette-Guérin (BCG) and to evaluate their natural history. Patients were divided into two groups based on the existence of previous bladder cancer (primary, non-primary). A logistic regression analysis was used to identify the possible differences in the probabilities of recurrence and progression with respect to tumor history, while potential differences due to gender, tumor size (> 3 cm, < 3 cm), stage (pTa, T1), concomitant carcinoma in situ (pTis) and number of tumors (single, multiple) were also assessed. Univariate and multivariate models were employed. In addition, Kaplan-Meier survival analysis was used to compare recurrence- and progression-free survival between the groups. A total of 192 patients were included (144 with primary and 48 with non-primary tumors). The rates of recurrence and progression for patients with primary tumors were 27.8% and 12.5%, respectively. The corresponding percentages for patients with non-primary tumors were 77.1% and 33.3%, respectively. The latter group of patients displayed significantly higher probabilities of recurrence (p=0.000; 95% confidence interval [CI], 4.067 to 18.804) and progression (p=0.002; 95% CI, 1.609 to 7.614) in a univariate logistic regression analysis. Previous bladder cancer history remained significant in the multivariate model accounting for history, age, gender, tumor size , number of tumors, stage and concomitant pTis (p=0.000; 95% CI, 4.367 to 21.924 and p=0.002; 95% CI, 1.611 to 8.182 for recurrence and progression respectively). Kaplan-Meier curves revealed that the non-primary group hadreduced progression- and recurrence-free survival. Previous non-muscle-invasive bladder cancer history correlates significantly with recurrence and progression in patients with high-risk non-muscle-invasive disease treated with adjuvant BCG.

TU-D-207B-01: A Prediction Model for Distinguishing Radiation Necrosis From Tumor Progression After Gamma Knife Radiosurgery Based On Radiomics Features From MR Images

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

Zhang, Z; MD Anderson Cancer Center, Houston, TX; Ho, A

Purpose: To develop and validate a prediction model using radiomics features extracted from MR images to distinguish radiation necrosis from tumor progression for brain metastases treated with Gamma knife radiosurgery. Methods: The images used to develop the model were T1 post-contrast MR scans from 71 patients who had had pathologic confirmation of necrosis or progression; 1 lesion was identified per patient (17 necrosis and 54 progression). Radiomics features were extracted from 2 images at 2 time points per patient, both obtained prior to resection. Each lesion was manually contoured on each image, and 282 radiomics features were calculated for eachmore » lesion. The correlation for each radiomics feature between two time points was calculated within each group to identify a subset of features with distinct values between two groups. The delta of this subset of radiomics features, characterizing changes from the earlier time to the later one, was included as a covariate to build a prediction model using support vector machines with a cubic polynomial kernel function. The model was evaluated with a 10-fold cross-validation. Results: Forty radiomics features were selected based on consistent correlation values of approximately 0 for the necrosis group and >0.2 for the progression group. In performing the 10-fold cross-validation, we narrowed this number down to 11 delta radiomics features for the model. This 11-delta-feature model showed an overall prediction accuracy of 83.1%, with a true positive rate of 58.8% in predicting necrosis and 90.7% for predicting tumor progression. The area under the curve for the prediction model was 0.79. Conclusion: These delta radiomics features extracted from MR scans showed potential for distinguishing radiation necrosis from tumor progression. This tool may be a useful, noninvasive means of determining the status of an enlarging lesion after radiosurgery, aiding decision-making regarding surgical resection versus conservative medical management.« less

The use of dynamic O-(2-18F-fluoroethyl)-l-tyrosine PET in the diagnosis of patients with progressive and recurrent glioma.

PubMed

Galldiks, Norbert; Stoffels, Gabriele; Filss, Christian; Rapp, Marion; Blau, Tobias; Tscherpel, Caroline; Ceccon, Garry; Dunkl, Veronika; Weinzierl, Martin; Stoffel, Michael; Sabel, Michael; Fink, Gereon R; Shah, Nadim J; Langen, Karl-Josef

2015-09-01

We evaluated the diagnostic value of static and dynamic O-(2-[(18)F]fluoroethyl)-L-tyrosine ((18)F-FET) PET parameters in patients with progressive or recurrent glioma. We retrospectively analyzed 132 dynamic (18)F-FET PET and conventional MRI scans of 124 glioma patients (primary World Health Organization grade II, n = 55; grade III, n = 19; grade IV, n = 50; mean age, 52 ± 14 y). Patients had been referred for PET assessment with clinical signs and/or MRI findings suggestive of tumor progression or recurrence based on Response Assessment in Neuro-Oncology criteria. Maximum and mean tumor/brain ratios of (18)F-FET uptake were determined (20-40 min post-injection) as well as tracer uptake kinetics (ie, time to peak and patterns of the time-activity curves). Diagnoses were confirmed histologically (95%) or by clinical follow-up (5%). Diagnostic accuracies of PET and MR parameters for the detection of tumor progression or recurrence were evaluated by receiver operating characteristic analyses/chi-square test. Tumor progression or recurrence could be diagnosed in 121 of 132 cases (92%). MRI and (18)F-FET PET findings were concordant in 84% and discordant in 16%. Compared with the diagnostic accuracy of conventional MRI to diagnose tumor progression or recurrence (85%), a higher accuracy (93%) was achieved by (18)F-FET PET when a mean tumor/brain ratio ≥2.0 or time to peak <45 min was present (sensitivity, 93%; specificity, 100%; accuracy, 93%; positive predictive value, 100%; P < .001). Static and dynamic (18)F-FET PET parameters differentiate progressive or recurrent glioma from treatment-related nonneoplastic changes with higher accuracy than conventional MRI. © 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.

Arterial Perfusion Imaging–Defined Subvolume of Intrahepatic Cancer

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

Wang, Hesheng, E-mail: hesheng@umich.edu; Farjam, Reza; Feng, Mary

2014-05-01

Purpose: To assess whether an increase in a subvolume of intrahepatic tumor with elevated arterial perfusion during radiation therapy (RT) predicts tumor progression after RT. Methods and Materials: Twenty patients with unresectable intrahepatic cancers undergoing RT were enrolled in a prospective, institutional review board–approved study. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) was performed before RT (pre-RT), after delivering ∼60% of the planned dose (mid-RT) and 1 month after completion of RT to quantify hepatic arterial perfusion. The arterial perfusions of the tumors at pre-RT were clustered into low-normal and elevated perfusion by a fuzzy clustering-based method, and the tumor subvolumesmore » with elevated arterial perfusion were extracted from the hepatic arterial perfusion images. The percentage changes in the tumor subvolumes and means of arterial perfusion over the tumors from pre-RT to mid-RT were evaluated for predicting tumor progression post-RT. Results: Of the 24 tumors, 6 tumors in 5 patients progressed 5 to 21 months after RT completion. Neither tumor volumes nor means of tumor arterial perfusion at pre-RT were predictive of treatment outcome. The mean arterial perfusion over the tumors increased significantly at mid-RT in progressive tumors compared with the responsive tumors (P=.006). From pre-RT to mid-RT, the responsive tumors had a decrease in the tumor subvolumes with elevated arterial perfusion (median, −14%; range, −75% to 65%), whereas the progressive tumors had an increase of the subvolumes (median, 57%; range, −7% to 165%) (P=.003). Receiver operating characteristic analysis of the percentage change in the subvolume for predicting tumor progression post-RT had an area under the curve of 0.90. Conclusion: The increase in the subvolume of the intrahepatic tumor with elevated arterial perfusion during RT has the potential to be a predictor for tumor progression post-RT. The tumor subvolume could be a radiation boost candidate for response-driven adaptive RT.« less

Recent Advances in Biointegrated Optoelectronic Devices.

PubMed

Xu, Huihua; Yin, Lan; Liu, Chuan; Sheng, Xing; Zhao, Ni

2018-05-28

With recent progress in the design of materials and mechanics, opportunities have arisen to improve optoelectronic devices, circuits, and systems in curved, flexible, stretchable, and biocompatible formats, thereby enabling integration of customized optoelectronic devices and biological systems. Here, the core material technologies of biointegrated optoelectronic platforms are discussed. An overview of the design and fabrication methods to form semiconductor materials and devices in flexible and stretchable formats is presented, strategies incorporating various heterogeneous substrates, interfaces, and encapsulants are discussed, and their applications in biomimetic, wearable, and implantable systems are highlighted. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Molecular Line and Continuum Opacities for Modeling of Extrasolar Giant Planet and Cool Stellar Atmospheres

NASA Technical Reports Server (NTRS)

Weck, P. F.; Schweitzer, A.; Stancil, P. C.; Hauschildt, P. H.; Kirby, K.; Yamaguchi, Y.; Allen, W. D.

2002-01-01

The molecular line and continuum opacities are investigated in the atmospheres of cool stars and Extrasolar Giant Planets (EGPs). Using a combination of ab inito and experimentally derived potential curves and dipole transition moments, accurate data have been calculated for rovibrationally-resolved oscillator strengths and photodissociation cross sections in the B' (sup 2)Sigma+ (left arrow) X (sup 2)Sigma+ and A (sup 2)Pi (left arrow) X (sup 2)Sigma+ band systems in MgH. We also report our progress on the study of the electronic structure of LiCl and FeH.

Progress in Suppressing Scattered Light into the Optical Beam Path of the NAO Rozhen 2m Telescope

NASA Astrophysics Data System (ADS)

Ovcharov, E. P.; Petrov, N.; Markov, H.; Bonev, T.; Donchev, Z.

2010-09-01

In this poster paper we present a summary of the published analysis of the spatial dependence of the magnitudes derived from images obtained in the RC focal plane of the 2m RCC NAO Rozhen telescope. An alert for the possible reason was the unusually curved flat-field images taken as a part of the standard CCD calibration procedure. The reasons for the problem are described and a solution is presented, which consists modification of the mirror baffles and mounting of special diaphragm at the entrance of the filter wheel.

Structural Characterization and Determinants of Specificity of Single- Chain Antibody Inhibitors of Membrane-Type Serine Protease 1

DTIC Science & Technology

2007-03-01

inset) defined the on rate as k1 =1.2×10 8 M−1s−1. The KIUN CO RR E Figure 1. Progress curves of MT-SP1 inhibition by scFv inhibitors reveal multiple...Farady 5d. PROJECT NUMBER 5e. TASK NUMBER E -Mail: christopher.farady@ucsf.edu 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND...library; pNA pAB, p-aminobenzamidine; ESI, elec E -mail address of the correspondi craik@cgl.ucsf.edu 0022-2836/$ - see front matter © 2007 P Please

Development and technical implementation of the separation nozzle process for enrichment of uranium-235

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

Becker, E.W.; Bier, W.; Bley, P.

In the separation nozzle process, enrichment is achieved by extremely high centrifugal forces in a curved flow of UF/sub 6/ diluted by a light gas. The first commercial application is in Brasil, where a so-called First Cascade consisting of 24 separation nozzle stages is under construction. In two steps, this installation will be expanded into a 300,000 SWU/a demonstration plant. The development of components for commercial plants is well under way. The paper describes developments and technical implementation of the separation nozzle process. Remarkable progress has been made in the process economy.

HDL and CER-001 Inverse-Dose Dependent Inhibition of Atherosclerotic Plaque Formation in apoE-/- Mice: Evidence of ABCA1 Down-Regulation

PubMed Central

Tardy, Claudine; Goffinet, Marine; Boubekeur, Nadia; Cholez, Guy; Ackermann, Rose; Sy, Gavin; Keyserling, Constance; Lalwani, Narendra; Paolini, John F.; Dasseux, Jean-Louis; Barbaras, Ronald; Baron, Rudi

2015-01-01

Objective CER-001 is a novel engineered HDL-mimetic comprised of recombinant human apoA-I and charged phospholipids that was designed to mimic the beneficial properties of nascent pre-ß HDL. In this study, we have evaluated the dose-dependent regulation of ABCA1 expression in vitro and in vivo in the presence of CER-001 and native HDL (HDL3). Methods and Results CER-001 induced cholesterol efflux from J774 macrophages in a dose-dependent manner similar to natural HDL. A strong down-regulation of the ATP-binding cassette A1 (ABCA1) transporter mRNA (- 50%) as well as the ABCA1 membrane protein expression (- 50%) was observed at higher doses of CER-001 and HDL3 compared to non-lipidated apoA-I. In vivo, in an apoE-/- mouse “flow cessation model,” in which the left carotid artery was ligatured to induce local inflammation, the inhibition of atherosclerotic plaque burden progression in response to a dose-range of every-other-day CER-001 or HDL in the presence of a high-fat diet for two weeks was assessed. We observed a U-shaped dose-response curve: inhibition of the plaque total cholesterol content increased with increasing doses of CER-001 or HDL3 up to a maximum inhibition (- 51%) at 5 mg/kg; however, as the dose was increased above this threshold, a progressively less pronounced inhibition of progression was observed, reaching a complete absence of inhibition of progression at doses of 20 mg/kg and over. ABCA1 protein expression in the same atherosclerotic plaque was decreased by-45% and-68% at 50 mg/kg for CER-001 and HDL respectively. Conversely, a-12% and 0% decrease in ABCA1 protein expression was observed at the 5 mg/kg dose for CER-001 and HDL respectively. Conclusions These data demonstrate that high doses of HDL and CER-001 are less effective at slowing progression of atherosclerotic plaque in apoE-/- mice compared to lower doses, following a U-shaped dose-response curve. A potential mechanism for this phenomenon is supported by the observation that high doses of HDL and CER-001 induce a rapid and strong down-regulation of ABCA1 both in vitro and in vivo. In conclusion, maximally efficient HDL- or CER-001-mediated cholesterol removal from atherosclerotic plaque is achieved by maximizing macrophage-mediated efflux from the plaque while minimizing dose-dependent down-regulation of ABCA1 expression. These observations may help define the optimal dose of HDL mimetics for testing in clinical trials of atherosclerotic burden regression. PMID:26335690

HDL and CER-001 Inverse-Dose Dependent Inhibition of Atherosclerotic Plaque Formation in apoE-/- Mice: Evidence of ABCA1 Down-Regulation.

PubMed

Tardy, Claudine; Goffinet, Marine; Boubekeur, Nadia; Cholez, Guy; Ackermann, Rose; Sy, Gavin; Keyserling, Constance; Lalwani, Narendra; Paolini, John F; Dasseux, Jean-Louis; Barbaras, Ronald; Baron, Rudi

2015-01-01

CER-001 is a novel engineered HDL-mimetic comprised of recombinant human apoA-I and charged phospholipids that was designed to mimic the beneficial properties of nascent pre-ß HDL. In this study, we have evaluated the dose-dependent regulation of ABCA1 expression in vitro and in vivo in the presence of CER-001 and native HDL (HDL3). CER-001 induced cholesterol efflux from J774 macrophages in a dose-dependent manner similar to natural HDL. A strong down-regulation of the ATP-binding cassette A1 (ABCA1) transporter mRNA (- 50%) as well as the ABCA1 membrane protein expression (- 50%) was observed at higher doses of CER-001 and HDL3 compared to non-lipidated apoA-I. In vivo, in an apoE-/- mouse "flow cessation model," in which the left carotid artery was ligatured to induce local inflammation, the inhibition of atherosclerotic plaque burden progression in response to a dose-range of every-other-day CER-001 or HDL in the presence of a high-fat diet for two weeks was assessed. We observed a U-shaped dose-response curve: inhibition of the plaque total cholesterol content increased with increasing doses of CER-001 or HDL3 up to a maximum inhibition (- 51%) at 5 mg/kg; however, as the dose was increased above this threshold, a progressively less pronounced inhibition of progression was observed, reaching a complete absence of inhibition of progression at doses of 20 mg/kg and over. ABCA1 protein expression in the same atherosclerotic plaque was decreased by-45% and-68% at 50 mg/kg for CER-001 and HDL respectively. Conversely, a-12% and 0% decrease in ABCA1 protein expression was observed at the 5 mg/kg dose for CER-001 and HDL respectively. These data demonstrate that high doses of HDL and CER-001 are less effective at slowing progression of atherosclerotic plaque in apoE-/- mice compared to lower doses, following a U-shaped dose-response curve. A potential mechanism for this phenomenon is supported by the observation that high doses of HDL and CER-001 induce a rapid and strong down-regulation of ABCA1 both in vitro and in vivo. In conclusion, maximally efficient HDL- or CER-001-mediated cholesterol removal from atherosclerotic plaque is achieved by maximizing macrophage-mediated efflux from the plaque while minimizing dose-dependent down-regulation of ABCA1 expression. These observations may help define the optimal dose of HDL mimetics for testing in clinical trials of atherosclerotic burden regression.

Equity in the use of public services for mother and newborn child health care in Pakistan: a utilization incidence analysis.

PubMed

Malik, Sadia Mariam; Ashraf, Nabila

2016-07-26

Poor maternal and infant health indicators are mostly concentrated among low income households in Pakistan and health care expenditures - especially on medical emergencies - are the most common income shocks experienced by the poor. Public investments in health are therefore considered as pro-poor interventions by the government of Pakistan. This study employs nationally representative household data for Pakistan for 2007-08 and 2010-11 to investigate whether benefits from publicly financed services on Mother and Newborn Child Health (MNCH) are effectively captured by the poor in terms of service utilization. The study conducts a Utilization Incidence Analysis of the use of public health services for MNCH in Pakistan. For this purpose, the utilization shares of households, ranked by economic status, are computed. The concentration curves are plotted and their dominance is tested against an equal distribution and Lorenz curves to determine whether the distribution is pro-poor and progressive. Although the shares of bottom income groups in the utilization of most services for MNCH have increased between 2007 and 2011, the utilization of some services such as post-natal consultation; institutional maternal delivery; and Tetanus Toxoid injections for pregnant women remains pro-rich in 2011. The utilization of pre-natal consultation, especially through lady health workers and visitors; the use of Family Panning Units; and immunization services is somewhat evenly distributed. The use of Basic Health Units (BHUs) is found to be pro-poor. The provincial analysis reveals that the province of Baluchistan depicts an unusually high level of inequity in the distribution of utilization benefits from almost all public health services. Finally, in terms of progressivity, public spending on all health services analyzed in the study is found to be progressive at the national level implying that investment in MNCH has the potential to redistribute income from rich to the poor. To target the poor effectively, the study recommends expanding the network of BHUs as well as basic reproductive and child health care services. The outreach of health facilities in Baluchistan need to be expanded while targeting the poor effectively by mitigating various access costs that prevent them from using public health services.

Stereotactic body radiation therapy for liver oligometastases: predictive factors of local response by 18F-FDG-PET/CT.

PubMed

Mazzola, Rosario; Fersino, Sergio; Alongi, Pierpaolo; Di Paola, Gioacchino; Gregucci, Fabiana; Aiello, Dario; Tebano, Umberto; Pasetto, Stefano; Ruggieri, Ruggero; Salgarello, Matteo; Alongi, Filippo

2018-05-23

To investigate metabolic parameters as predictive of local response after stereotactic body radiation therapy (SBRT) for liver-oligometastases. Inclusion criteria of the present retrospective study were: (a) liver oligometastases with controlled primary tumor; (b) absence of progressive disease ≥6 months; (c) metastases ≤ 3; (d) evaluation of SBRT-response by means of 18-fludeoxyglucose-PET/CT for at least two subsequent evaluations; (e) Karnofsky performance status >80; (f) life-expectancy >6 months. The following metabolic parameters were defined semi-quantitatively for each metastases: (1) standardized uptake value (SUVmax; (2) SUV-mean; (3) metabolic tumor volume (MTV), tumor volume with a SUV ≥3, threshold 40%; (4) total lesion glycolysis (TLG), i.e. the product of SUV-mean and MTV. Local control was defined as absence of recurrence in the field of irradiation. 41 liver metastases were analyzed. Pre-SBRT, median SUV-max was 8.7 (range, 4.5-23.59), median SUV-mean was 4.6 (range, 3-7.5), median MTV was 5.7 cc (range, 0.9-80.6) and median total lesion glycolysis was 24.1 (range, 3.6-601.5). At statistical analysis, metastases with SUV-mean >5 (p 0.04; odds ratio 4.75, sensitivity = 50%, specificity = 82.6%, area under the curve 0.66) and SUV-max >12 (p 0.02; odds ratio 5.03, sensitivity = 69%, specificity = 70%, area under the curve = 0.69) showed higher rates of infield-failure compared to the remaining lesions. According to current findings, pre-SBRT SUV-max and SUV-mean could be predictable of local response in liver oligometastases. Advances in knowledge: Present findings could support the hypothesis that fludeoxyglucose-PET/CT may be a powerful tool to predict tumor control. Specifically, current results might be helpful for clinicians in the decision-making process regarding liver oligometastatic patient selection as well as the individual therapy stratification distinguishing between slowly local progressing patients and rapidly progressing patients.

Serum miR-206 and other muscle-specific microRNAs as non-invasive biomarkers for Duchenne muscular dystrophy.

PubMed

Hu, Jun; Kong, Min; Ye, Yuanzhen; Hong, Siqi; Cheng, Li; Jiang, Li

2014-06-01

Creatine kinase has been utilized as a diagnostic marker for Duchenne muscular dystrophy (DMD), but it correlates less well with the DMD pathological progression. In this study, we hypothesized that muscle-specific microRNAs (miR-1, -133, and -206) in serum may be useful for monitoring the DMD pathological progression, and explored the possibility of these miRNAs as potential non-invasive biomarkers for the disease. By using real-time quantitative reverse transcription-polymerase chain reaction in a randomized and controlled trial, we detected that miR-1, -133, and -206 were significantly over-expressed in the serum of 39 children with DMD (up to 3.20 ± 1.20, 2(-ΔΔCt) ): almost 2- to 4-fold enriched in comparison to samples from the healthy controls (less than 1.15 ± 0.34, 2(-ΔΔCt) ). To determine whether these miRNAs were related to the clinical features of children with DMD, we analyzed the associations compared to creatine kinase. There were very good inverse correlations between the levels of these miRNAs, especially miR-206, and functional performances: high levels corresponded to low muscle strength, muscle function, and quality of life. Moreover, by receiver operating characteristic curves analyses, we revealed that these miRNAs, especially miR-206, were able to discriminate DMD from controls. Thus, miR-206 and other muscle-specific miRNAs in serum are useful for monitoring the DMD pathological progression, and hence as potential non-invasive biomarkers for the disease. There has been a long-standing need for reliable, non-invasive biomarkers for Duchenne muscular dystrophy (DMD). We found that the levels of muscle-specific microRNAs, especially miR-206, in the serum of DMD were 2- to 4-fold higher than in the controls. High levels corresponded to low muscle strength, muscle function, and quality of life (QoL). These miRNAs were able to discriminate DMD from controls by receiver operating characteristic (ROC) curves analyses. Thus, miR-206 and other muscle-specific miRNAs are useful as non-invasive biomarkers for DMD. © 2014 International Society for Neurochemistry.

Circulating human papillomavirus DNA as a surveillance tool in head and neck squamous cell carcinoma: a systematic review and meta-analysis.

PubMed

Jensen, Kristina Kvist; Grønhøj, Christian; Jensen, David H; von Buchwald, Christian

2018-05-15

The incidence of human papillomavirus-induced (HPV+) head and neck squamous cell carcinoma (HNSCC) i.e. especially oropharyngeal cancers (OPSCC) is increasing and a significant proportion of patients encounter disease progression. A simple and sensitive test to identify patients with progression is an unmet need. To systematically review the literature and carry out a meta-analysis of studies, investigated circulating HPV-DNA as a biomarker for disease progression in patients with HNSCC. A systematic review and meta-analysis. PubMed, Embase and the Cochrane Library were systematically searched for articles published in English from January 1980 to November 2017. Search terms used were related to HPV, cancer sites, blood-based biomarkers and terms for specific use settings. Articles reviewed and selected by authors and data on study design, demographic variables, location, HPV status, number of pre treatment blood tests, number of post treatment blood tests, blood HPV status and number of recurrences and length of follow-up was extracted. A meta-analysis of HPV-DNA as a diagnostic test for recurrence by means of a hierarchical summary receiver operating curve (HSROC) model was performed. We identified five studies (n=600 subjects) examining circulating HPV-DNA in patients with HNSCC. In these five studies (n=411) patients had both pre and post treatment blood samples. The pooled sensitivity, in detecting a recurrence was estimated to be 54% (95% CI: 32%-74%), while the pooled specificity was 98% (95% CI: 93-99.4%). The pooled false-positive rate is 2% (95% CI: 0.6%-7%). The area under the curve (AUC) of the summary HSROC was 0.93. Positive predictive value was estimated to 93% and the negative predictive value to 94%. Plasma HPV-DNA is a promising tool for surveillance in patients with HPV-related HNSCC i.e. OPSCC and has a high specificity. By recent technical advances and by increasing follow-up blood samples the sensitivity could likely be improved. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Glucocorticoid treatment for the prevention of scoliosis in children with Duchenne muscular dystrophy: long-term follow-up.

PubMed

Lebel, David E; Corston, John A; McAdam, Laura C; Biggar, W Douglas; Alman, Benjamin A

2013-06-19

Duchenne muscular dystrophy, a progressive muscle disorder that occurs in males, causes a gradual decline in muscle strength. This progressive decline is associated with the development of scoliosis. Previous studies have shown that the use of glucocorticoids slows the progression of scoliosis, but it is unknown if the spine remains straight in the long term. We examined if glucocorticoid treatment has a long-term effect on the prevalence of scoliosis. Fifty-four boys who had been diagnosed with Duchenne muscular dystrophy while they were still walking were enrolled in a non-randomized comparative study of the glucocorticoid deflazacort. The families of thirty boys elected for them to use glucocorticoid treatment and the families of twenty-four boys elected for them not to have this treatment. The boys were matched for important baseline characteristics including age and pulmonary function. Every four to six months, they were examined for the development of scoliosis, and the duration of follow-up for surviving patients was fifteen years. Because surgery was recommended for spinal curves measuring >20° on sitting posteroanterior radiographs, a curve of this magnitude was used as the definition for a patient developing scoliosis. Five boys (21%) in the non-treatment group and one boy (3%) in the glucocorticoid treatment group died. At the most recent follow-up, of the boys who survived, six (20%) in the glucocorticoid treatment group and twenty-two (92%) in the non-treatment group developed scoliosis and underwent spinal surgery. After fifteen years of follow-up, the survivorship analysis (avoiding surgery) was 78% (95% confidence interval, 57% to 89%) in the treatment group and 8.3% (95% confidence interval, 0.8% to 28%) in the non-treatment group. Significance (p = 5.8 × 10(-7)) was calculated with log-rank and chi-square tests. None of the patients in the glucocorticoid group developed scoliosis after ten years of deflazacort treatment. The long-term use of the glucocorticoid results in a substantial decreased need for spinal surgery to treat scoliosis.

Decreased synovial fluid ghrelin levels are linked with disease severity in primary knee osteoarthritis patients and are increased following laser therapy.

PubMed

Zou, Yu-Cong; Deng, Hong-Yu; Mao, Zheng; Zhao, Chang; Huang, Ju; Liu, Gang

2017-07-01

Ghrelin has been proved to inhibit inflammation and promote cartilage growth. So far, its role in patients with primary knee osteoarthritis has not been investigated. The current study was performed to explore the serum and synovial ghrelin levels as well as the relationship between ghrelin levels and disease severity in primary knee OA patients. 52 primary knee OA patients were recruited in the study. 52 sex and age-matched patients visiting our hospital for regular body check were selected as controls. The serum and synovial fluid ghrelin levels were examined by enzyme linked immunosorbent assay (ELISA) before treatment, one week and four weeks after laser therapy, respectively. The inflammation markers IL-6 and TNF-α were also investigated. The radiographic progression was assessed by Kellgren-Lawrence (K-L) grade scale and the symptomatic severity was evaluated by visual analog scale (VAS), Lequesne index and Lysholm scores. The Receiver Operating Characteristic (ROC) analysis curve was conducted to test the diagnostic value of ghrelin, IL-6 and TNF-α for radiographic progression. No significant difference of serum ghrelin levels was found between knee OA patients and healthy controls. Synovial fluid ghrelin concentrations were significantly negatively correlated with K-L grading (r=-0.591, P<0.001).Attenuated synovial fluid ghrelin levels were also related to clinical severity determined by Lequesne index (r=-0.308, P=0.025),VAS scores (r=-0.591, P<0.001) and Lysholm scores (r=0.381, P=0.005).In addition, ghrelin levels were also negatively associated with TNF-α (r=-0.424, P=0.002) and IL-6 concentrations (r=-0.428, P=0.002). ROC curve analysis demonstrated that ghrelin exhibited more diagnostic value than IL-6 and TNF-α for assessing radiographic progression in medium-late stage. Decreased synovial fluid ghrelin levels are related to disease severity in patients with primary osteoarthritis and are increased following laser therapy. Local application of ghrelin may serve as an adjunctive therapy for knee OA. Copyright © 2017. Published by Elsevier B.V.

Vertical-axis wind turbine development in Canada

NASA Astrophysics Data System (ADS)

Templin, R. J.; Rangi, R. S.

1983-12-01

Recent Canadian progress in the development of the curved-blade Darrieus vertical-axis wind turbine (VAWT) is described. Cooperation between government, industry and power utilities in the conduct of field trials, over several years, has demonstrated improved performance and reliability of grid-coupled turbines of this type. The rated power of the VAWTs currently under test ranges from 30 kW, in a wind/diesel powerplant, to 230 kW, in an installation on an island in the Gulf of St. Lawrence. Progress has also been made in understanding the basic aerodynamic behavior of the VAWT and theoretical methods for performance and load prediction have correspondingly improved. A brief description is given of 'Project EOLE', a cooperative project between the federal government and the utility Hydro-Quebec to develop and test, during the next two to three years, a 4 MW VAWT prototype, which will be coupled to the power grid at a location on the south shore of the St. Lawrence River.

Restricted mobility of side chains on concave surfaces of solenoid proteins may impart heightened potential for intermolecular interactions.

PubMed

Ramya, L; Gautham, N; Chaloin, Laurent; Kajava, Andrey V

2015-09-01

Significant progress has been made in the determination of the protein structures with their number today passing over a hundred thousand structures. The next challenge is the understanding and prediction of protein-protein and protein-ligand interactions. In this work we address this problem by analyzing curved solenoid proteins. Many of these proteins are considered as "hub molecules" for their high potential to interact with many different molecules and to be a scaffold for multisubunit protein machineries. Our analysis of these structures through molecular dynamics simulations reveals that the mobility of the side-chains on the concave surfaces of the solenoids is lower than on the convex ones. This result provides an explanation to the observed preferential binding of the ligands, including small and flexible ligands, to the concave surface of the curved solenoid proteins. The relationship between the landscapes and dynamic properties of the protein surfaces can be further generalized to the other types of protein structures and eventually used in the computer algorithms, allowing prediction of protein-ligand interactions by analysis of protein surfaces. © 2015 Wiley Periodicals, Inc.

Extraction of pore-morphology and capillary pressure curves of porous media from synchrotron-based tomography data

DOE PAGES

Yang, Feifei; Hingerl, Ferdinand F.; Xiao, Xianghui; ...

2015-06-03

The elevated level of atmospheric carbon dioxide (CO 2) has caused serious concern of the progression of global warming. Geological sequestration is considered as one of the most promising techniques for mitigating the damaging effect of global climate change. Investigations over wide range of length-scales are important for systematic evaluation of the underground formations from prospective CO 2 reservoir. Understanding the relationship between the micro morphology and the observed macro phenomena is even more crucial. Here we show Synchrotron based X-ray micro tomographic study of the morphological buildup of Sandstones. We present a numerical method to extract the pore sizesmore » distribution of the porous structure directly, without approximation or complex calculation. We have also demonstrated its capability in predicting the capillary pressure curve in a mercury intrusion porosimetry (MIP) measurement. The method presented in this work can be directly applied to the morphological studies of heterogeneous systems in various research fields, ranging from Carbon Capture and Storage, and Enhanced Oil Recovery to environmental remediation in the vadose zone.« less

Phonon dynamics of graphene on metals

NASA Astrophysics Data System (ADS)

Taleb, Amjad Al; Farías, Daniel

2016-03-01

The study of surface phonon dispersion curves is motivated by the quest for a detailed understanding of the forces between the atoms at the surface and in the bulk. In the case of graphene, additional motivation comes from the fact that thermal conductivity is dominated by contributions from acoustic phonons, while optical phonon properties are essential to understand Raman spectra. In this article, we review recent progress made in the experimental determination of phonon dispersion curves of graphene grown on several single-crystal metal surfaces. The two main experimental techniques usually employed are high-resolution electron energy loss spectroscopy (HREELS) and inelastic helium atom scattering (HAS). The different dispersion branches provide a detailed insight into the graphene-substrate interaction. Softening of optical modes and signatures of the substrate‧s Rayleigh wave are observed for strong graphene-substrate interactions, while acoustic phonon modes resemble those of free-standing graphene for weakly interacting systems. The latter allows determining the bending rigidity and the graphene-substrate coupling strength. A comparison between theory and experiment is discussed for several illustrative examples. Perspectives for future experiments are discussed.

Contemporary labor patterns: the impact of maternal body mass index.

PubMed

Kominiarek, Michelle A; Zhang, Jun; Vanveldhuisen, Paul; Troendle, James; Beaver, Julie; Hibbard, Judith U

2011-09-01

We sought to compare labor patterns by body mass index (BMI). A total of 118,978 gravidas with a singleton term cephalic gestation were studied. Repeated-measures analysis constructed mean labor curves by parity and BMI categories for those who reached 10 cm. Interval-censored regression analysis determined median traverse times, adjusting for covariates in vaginal deliveries and intrapartum cesareans. In the labor curves, the time difference to reach 10 cm was 1.2 hours from the lowest to highest BMI category for nulliparas. Multiparas entered active phase by 6 cm, but reaching this point took longer for BMI ≥40.0 (3.4 hours) compared to BMI <25.0 (2.4 hours). Progression by centimeter (P < .001 for nulliparas) and from 4-10 cm (P < .001 for nulliparas and multiparas) increased as BMI increased. Second stage length, with and without an epidural, was similar among BMI categories for nulliparas (P > .05) but decreased as BMI increased for multiparas (P < .001). Labor proceeds more slowly as BMI increases, suggesting that labor management be altered to allow longer time for these differences. Copyright © 2011 Mosby, Inc. All rights reserved.

A meta-analysis of education effects on chronic disease: the causal dynamics of the Population Education Transition Curve.

PubMed

Smith, William C; Anderson, Emily; Salinas, Daniel; Horvatek, Renata; Baker, David P

2015-02-01

As the Epidemiological Transition progresses worldwide, chronic diseases account for the majority of deaths in developed countries and a rising proportion in developing countries indicating a new global pattern of mortality and health challenges into the future. Attainment of formal education is widely reported to have a negative gradient with risk factors and onset of chronic disease, yet there has not been a formal assessment of this research. A random-effects meta-analysis finds that across 414 published effects more education significantly reduces the likelihood of chronic disease, except for neoplastic diseases with substantial genetic causes. Some studies, however, report null effects and other research on infectious disease report positive education gradients. Instead of assuming these contradictory results are spurious, it is suggested that they are part of a predictable systemic interaction between multiple mediating effects of education and the Epidemiological Transition stage of the population; and thus represent one case of the Population Education Transition Curve modeling changes in the association between education and health as dependent on population context. Copyright © 2014 Elsevier Ltd. All rights reserved.

Water nanodroplet thermodynamics: quasi-solid phase-boundary dispersivity.

PubMed

Zhang, Xi; Sun, Peng; Huang, Yongli; Ma, Zengsheng; Liu, Xinjuan; Zhou, Ji; Zheng, Weitao; Sun, Chang Q

2015-04-23

It has long been puzzling that water nanodroplets undergo simultaneously "supercooling" at freezing and "superheating" at melting. Recent progress (Sun et al. J. Phys. Chem. Lett. 2013, 4, 2565, 3238) enables us to resolve this anomaly from the perspective of hydrogen bond (O:H-O) specific heat disparity. A superposition of the specific heat ηx(T) curves for the H-O bond (x = H) and the O:H nonbond (x = L) defines two intersecting temperatures that form the ice/quasi-solid/liquid phase boundaries. Molecular undercoordination (with fewer than four nearest neighbors in the bulk) stretches the ηH(T) curve by raising the Debye temperature ΘDH through H-O bond shortening and phonon stiffening. The ηH(T) stretching is coupled with the ηL(T) depressing because of the Coulomb repulsion between electron pairs on oxygen ions. The extent of dispersion varies with the size of a droplet that prefers a core-shell structure configuration-the bulk interior and the skin. Understandings may open an effective way of dealing with the thermodynamic behavior of water droplets and bubbles from the perspective of O:H-O bond cooperativity.

Evaluation of cerebral-cardiac syndrome using echocardiography in a canine model of acute traumatic brain injury.

PubMed

Qian, Rong; Yang, Weizhong; Wang, Xiumei; Xu, Zhen; Liu, Xiaodong; Sun, Bing

2015-01-01

Previous studies have confirmed that traumatic brain injury (TBI) can induce general adaptation syndrome (GAS), which subsequently results in myocardial dysfunction and damage in some patients with acute TBI; this condition is also termed as cerebral-cardiac syndrome. However, most clinicians ignore the detection and treatment of myocardial dysfunction, and instead concentrate only on the serious neural damage that is observed in acute TBI, which is one of the most important fatal factors. Therefore, clarification is urgently needed regarding the relationship between TBI and myocardial dysfunction. In the present study, we evaluated 18 canine models of acute TBI, by using real-time myocardial contrast echocardiography and strain rate imaging to accurately evaluate myocardial function and regional microcirculation, including the strain rate of the different myocardial segments, time-amplitude curves, mean ascending slope of the curve, and local myocardial blood flow. Our results suggest that acute TBI often results in cerebral-cardiac syndrome, which rapidly progresses to the serious stage within 3 days. This study is the first to provide comprehensive ultrasonic characteristics of cerebral-cardiac syndrome in an animal model of TBI.

High-order numerical simulations of pulsatile flow in a curved artery model

NASA Astrophysics Data System (ADS)

Cox, Christopher; Liang, Chunlei; Plesniak, Michael W.

2016-11-01

Cardiovascular flows are pulsatile, incompressible and occur in complex geometries with compliant walls. Together, these factors can produce an environment that can affect the progression of cardiovascular disease by altering wall shear stresses. Unstructured high-order CFD methods are well suited for capturing unsteady vortex-dominated viscous flows, and these methods provide high accuracy for similar cost as low-order methods. We use an in-house three-dimensional flux reconstruction Navier-Stokes solver to simulate secondary flows and vortical structures within a rigid 180-degree curved artery model under pulsatile flow of a Newtonian blood-analog fluid. Our simulations use a physiological flowrate waveform taken from the carotid artery. We are particularly interested in the dynamics during the deceleration phase of the waveform, where we observe the deformed-Dean, Dean, Lyne and Wall vortices. Our numerical results reveal the complex nature of these vortices both in space and time and their effect on overall wall shear stress. Numerical results agree with and complement experimental results obtained in our laboratory using particle image velocimetry. Supported by the GW Center for Biomimetics and Bioinspired Engineering.

Relationship between icotinib hydrochloride exposure and clinical outcome in Chinese patients with advanced non-small cell lung cancer.

PubMed

Ni, Jun; Liu, Dong-Yang; Hu, Bei; Li, Chen; Jiang, Ji; Wang, Han-Ping; Zhang, Li

2015-09-01

The current study was conducted to explore the relationship between icotinib hydrochloride exposure and therapeutic effects in Chinese patients with advanced non-small cell lung cancer (NSCLC) who were treated with icotinib hydrochloride. A total of 30 patients with NSCLC who were treated with icotinib hydrochloride were chosen from a single-center, open-label, phase 1 dose escalation clinical trial. Different doses of icotinib hydrochloride were administered orally for 28 consecutive days in different groups until disease progression or unacceptable toxicities occurred. Blood samples were collected during the first treatment cycle (day 1-28) for the pharmacokinetic analysis. Tumor responses were assessed according to the Response Evaluation Criteria in Solid Tumors (RECIST). The plasma concentrations of icotinib hydrochloride were assessed by liquid chromatography-mass spectrometry. Thirty patients with a median age of 56 years old (50% of whom were female) were enrolled. For single-dose treatment, the plasma pharmacokinetics demonstrated a median time to maximum concentration of 0.5 to 4 hours and a mean terminal elimination half-life of 6.21±3.44 hours at the 150-mg dose and 10.1±12.18 hours at the 200-mg dose. For multiple-dose treatment, the last measurable concentration (Clast ) was 708±368.67 ng/mL at the 150-mg every 12 hours, 782.73±618.18 ng/mL at the 200-mg every 12 hours, and 1162±658.44 ng/mL at the 125-mg every 8 hours; the under the concentration curve from time 0 to Clast was 14.5±2.43 hour*mg/mL, 13.2±2.5 hour*mg/mL, and 12.19±2.47 hour*mg/mL, respectively. At the dose of 150 mg every 12 hours, 1 patient with an epidermal growth factor receptor (EGFR) exon 19 deletion achieved a complete response for 10 months; another patient who carried the EGFR exon 19 deletion achieved stable disease for 6 months. Univariate analysis demonstrated that the time to maximum plasma concentration (Tmax ) after a single dose of icotinib hydrochloride was significantly correlated with the overall survival (OS) (Spearman correlation coefficient, 0.441; P = .012). The disease control rate was correlated with Tmax after a single dose (Spearman correlation coefficient, 0.518; P = .011). Multivariate analysis demonstrated that the area under the concentration-time curve from 0 to last determination time and the area under the curve from 0 to infinite time after a single dose of icotinib hydrochloride were correlated with OS (P = .037 and .042, respectively). The Clast was found to affect progression-free survival (P = .016). Stratification of these patients according to smoking status indicated significant correlation between OS and the area under the concentration-time curve from 0 to last determination time (Spearman correlation coefficient, -0.709; P = .015). Patients with a longer Tmax and higher exposure might experience longer OS and a higher disease control rate. In addition, the increased Clast might prolong the progressive-free survival of patients. However, the relationships between EGFR mutation, pharmacokinetics, and clinical outcomes require further research. © 2015 American Cancer Society.

Weight-Independent Percentile Chart of 2880 Gastric Bypass Patients: a New Look at Bariatric Weight Loss Results.

PubMed

van de Laar, Arnold W; de Brauw, Maurits; Bruin, Sjoerd C; Acherman, Yair I

2016-12-01

Percentile charts would be ideal for assessing sufficient weight loss in bariatric surgery. They allow comparing individual results to the outcome of many others, at any postoperative time. Unfortunately, percentile charts can be problematic when comparing unequally heavy peers, a circumstance not uncommon among bariatric patients. We investigate the relevance of this disadvantage and combine new insights to improve the practical use of percentile charts in bariatric surgery. Laparoscopic Roux-en-Y gastric bypass outcome expressed with body mass index (BMI), excess weight loss (%EWL), total weight loss (%TWL), and alterable weight loss (%AWL), a new metric rendering outcome independent of baseline BMI, is used to build percentile curves p97/p90/p75/p50/p25/p10/p03 with the lambda-mu-sigma method. We used the %AWL p25 curve as baseline BMI-independent reference for sufficient weight loss and compared it to p25 curves based on common metrics and to traditional criteria ≥50 % EWL, <25 % EWL, and BMI < 35 kg/m 2 . We operated 2880 patients, with baseline BMI of 43.4 kg/m 2 , follow-up 71 %, and mean of 23.3 (0-87.6) months. Independent %AWL outcome is presented in one percentile chart. Percentile curves p25/p50/p75 show 40/48/57 % AWL at nadir 15/16/19 months, 35/45/54 % AWL at 3 years, and 30/38/47 % AWL at 7 years. Traditional criteria and p25 curves based on %EWL and BMI match with most sufficient results (high sensitivities), but overlook many insufficient results (low specificities). We present the first baseline BMI-independent bariatric weight loss percentile chart. It allows comparing heavier patients to lighter peers and vice versa, at any postoperative time, up to 7 years. With these advantages, we compared it to traditional bariatric criteria like ≥50 % EWL and found that they are weak in recognizing insufficient weight loss. The visual aspect of consecutive results plotted on a chart among the percentile curves of peers conveys a strong, intuitive message on the personal progress of postoperative weight loss.

Perils of the new labor management guidelines.

PubMed

Cohen, Wayne R; Friedman, Emanuel A

2015-04-01

Recent guidelines issued jointly by the American College of Obstetricians and Gynecologists and the Society for Maternal-Fetal Medicine for assessing labor progress differ substantially from those described initially by Friedman, which have guided clinical practice for decades. The guidelines are based on results obtained from new and untested methods of analyzing patterns of cervical dilatation and fetal descent. Before these new guidelines are adopted into clinical practice, the results obtained by these unconventional analytic approaches should be validated and shown to be superior, or at least equivalent, to currently accepted standards. The new guidelines indicate the patterns of labor originally described by Friedman are incorrect and, further, are inapplicable to modern obstetric practice. We contend that the original descriptions of normal and abnormal labor progress, which were based on direct clinical observations, accurately describe progress in dilatation and descent, and that the differences reported more recently are likely attributable to patient selection and the potential inaccuracy of very high-order polynomial curve-fitting methods. The clinical evaluation of labor is a process of serially estimating the likelihood of a safe vaginal delivery. Because many factors contribute to that likelihood, such as cranial molding, head position and attitude, and the bony architecture and capacity of the pelvis, graphic labor patterns should never be used in isolation. The new guidelines are based heavily on unvalidated notions of labor progress and ignore clinical parameters that should remain cornerstones of intrapartum decision-making. Copyright © 2015. Published by Elsevier Inc.

Analysis of the learning curve for transurethral resection of the prostate. Is there any influence of musical instrument and video game skills on surgical performance?

PubMed Central

Yamaçake, Kleiton Gabriel Ribeiro; Nakano, Elcio Tadashi; Soares, Iva Barbosa; Cordeiro, Paulo; Srougi, Miguel; Antunes, Alberto Azoubel

2015-01-01

Objective To evaluate the learning curve for transurethral resection of the prostate (TURP) among urology residents and study the impact of video game and musical instrument playing abilities on its performance. Material and methods A prospective study was performed from July 2009 to January 2013 with patients submitted to TURP for benign prostatic hyperplasia. Fourteen residents operated on 324 patients. The following parameters were analyzed: age, prostate-specific antigen levels, prostate weight on ultrasound, pre- and postoperative serum sodium and hemoglobin levels, weight of resected tissue, operation time, speed of resection, and incidence of capsular lesions. Gender, handedness, and prior musical instrument and video game playing experience were recorded using survey responses. Results The mean resection speed in the first 10 procedures was 0.36 g/min and reached a mean of 0.51 g/min after the 20th procedure. The incidence of capsular lesions decreased progressively. The operation time decreased progressively for each subgroup regardless of the difference in the weight of tissue resected. Those experienced in playing video games presented superior resection speed (0.45 g/min) when compared with the novice (0.35 g/min) and intermediate (0.38 g/min) groups (p=0.112). Musical instrument playing abilities did not affect the surgical performance. Conclusion Speed of resection, weight of resected tissue, and percentage of resected tissue improve significantly and the incidence of capsular lesions reduces after the performance of 10 TURP procedures. Experience in playing video games or musical instruments does not have a significant effect on outcomes. PMID:26516596

The influence of renal manifestations to the progression of autosomal dominant polycystic kidney disease

PubMed Central

Idrizi, A; Barbullushi, M; Petrela, E; Kodra, S; Koroshi, A; Thereska, N

2009-01-01

Background: Renal stones, urinary tract infections (UTI) and gross hematuria (GH) are the most important renal manifestations of autosomal dominant polycystic kidney disease (ADPKD). They are not only common, but are also frequent cause of morbidity, influencing renal dysfunction. The aim of this study was to evaluate the frequency of these manifestations in our patients with ADPKD and their impact on renal function. Methods: One hundred eighty ADPKD patients were included in the study. Subjects were studied for the presence of UTI, gross hematuria frequency and responsible factors of nephrolithiasis. Survival times were calculated as the time to renal replacement therapy or time of serum creatinine value up to 10 mg/dl. Kaplan-Meier product-limit survival curves were constructed, and log rank test was used to compare the survival curves. Results: Kidney stones were present in 76/180 (42% of pts). The stones were composed of urate (47%) calcium oxalate (39%), and other compounds 14%. UTI was observed in 60% (108 patients). Patients treated with urinary disinfectants had a significant lower frequency of urinary infection (p<0.001) and hematuria (p<0.001) after one year than untreated patients. Gross hematuria was present in 113 patients (63%). In 43 patients hematuria was diagnosed before age 30 (38%), while in 70 patients it was diagnosed after age 30 (62%). Conclusions: UTI is frequent in our ADPKD patients. The correct treatment of UTI decreases its frequency and has beneficial role in the rate of progression to renal failure in ADPKD patients. Patients with recurrent episodes of gross hematuria may be at risk for more severe renal disease. PMID:19918304

Progress towards Continental River Dynamics modeling

NASA Astrophysics Data System (ADS)

Yu, Cheng-Wei; Zheng, Xing; Liu, Frank; Maidment, Daivd; Hodges, Ben

2017-04-01

The high-resolution National Water Model (NWM), launched by U.S. National Oceanic and Atmospheric Administration (NOAA) in August 2016, has shown it is possible to provide real-time flow prediction in rivers and streams across the entire continental United States. The next step for continental-scale modeling is moving from reduced physics (e.g. Muskingum-Cunge) to full dynamic modeling with the Saint-Venant equations. The Simulation Program for River Networks (SPRNT) provides a computational approach for the Saint-Venant equations, but obtaining sufficient channel bathymetric data and hydraulic roughness is seen as a critical challenge. However, recent work has shown the Height Above Nearest Drainage (HAND) method can be applied with the National Elevation Dataset (NED) to provide automated estimation of effective channel bathymetry suitable for large-scale hydraulic simulations. The present work examines the use of SPRNT with the National Hydrography Dataset (NHD) and HAND-derived bathymetry for automated generation of rating curves that can be compared to existing data. The approach can, in theory, be applied to every stream reach in the NHD and thus provide flood guidance where none is available. To test this idea we generated 2000+ rating curves in two catchments in Texas and Alabama (USA). Field data from the USGS and flood records from an Austin, Texas flood in May 2015 were used as validation. Large-scale implementation of this idea requires addressing several critical difficulties associated with numerical instabilities, including ill-posed boundary conditions generated in automated model linkages and inconsistencies in the river geometry. A key to future progress is identifying efficient approaches to isolate numerical instability contributors in a large time-space varying solution. This research was supported in part by the National Science Foundation under grant number CCF-1331610.

Randomized, phase II trial of pemetrexed and carboplatin with or without enzastaurin versus docetaxel and carboplatin as first-line treatment of patients with stage IIIB/IV non-small cell lung cancer.

PubMed

Socinski, Mark A; Raju, Robert N; Stinchcombe, Thomas; Kocs, Darren M; Couch, Linda S; Barrera, David; Rousey, Steven R; Choksi, Janak K; Jotte, Robert; Patt, Debra A; Periman, Phillip O; Schlossberg, Howard R; Weissman, Charles H; Wang, Yunfei; Asmar, Lina; Pritchard, Sharon; Bromund, Jane; Peng, Guangbin; Treat, Joseph; Obasaju, Coleman K

2010-12-01

Enzastaurin is an oral serine/threonine kinase inhibitor that targets protein kinase C-beta (PKC-β) and the phosphatidylinositol-3-kinase/AKT pathway. This trial assessed pemetrexed-carboplatin ± enzastaurin to docetaxel-carboplatin in advanced non-small cell lung cancer. Patients with stage IIIB (with pleural effusion) or IV non-small cell lung cancer and performance status 0 or 1 were randomized to one of the three arms: (A) pemetrexed 500 mg/m and carboplatin area under the curve 6 once every 3 weeks for up to 6 cycles with a loading dose of enzastaurin 1125 or 1200 mg followed by 500 mg daily until disease progression, (B) the same regimen of pemetrexed-carboplatin without enzastaurin, or (C) docetaxel 75 mg/m and carboplatin area under the curve 6 once every 3 weeks for up to six cycles. The primary end point was time to disease progression (TTP). Between March 2006 and May 2008, 218 patients were randomized. Median TTP was 4.6 months for pemetrexed-carboplatin-enzastaurin, 6.0 months for pemetrexed-carboplatin, and 4.1 months for docetaxel-carboplatin (differences not significant). Median survival was 7.2 months for pemetrexed-carboplatin-enzastaurin, 12.7 months for pemetrexed-carboplatin, and 9.2 months for docetaxel-carboplatin (log-rank p = 0.05). Compared with the other arms, docetaxel-carboplatin was associated with lower rates of grade 3 thrombocytopenia and anemia but a higher rate of grade 3 or 4 febrile neutropenia. There was no difference in TTP between the three arms, but survival was longer with pemetrexed-carboplatin compared with docetaxel-carboplatin. Enzastaurin did not add to the activity of pemetrexed-carboplatin.

Monitoring Progress in Population Health: Trends in Premature Death Rates

PubMed Central

Catlin, Bridget B.; Kindig, David A.

2013-01-01

Introduction Trends in population health outcomes can be monitored to evaluate the performance of population health systems at the national, state, and local levels. The objective of this study was to compare and contrast 4 measures for assessing progress in population health improvement by using age-adjusted premature death rates as a summary measure of the overall health outcomes in the United States and in all 50 states. Methods To evaluate the performance of statewide population health systems during the past 20 years, we used 4 measures of age-adjusted premature (<75 years of age) death rates: current rates (2009), baseline trends (1990s), follow-up trends (2000s), and changes in trends from baseline to the follow-up periods (ie, “bending the curve”). Results Current premature death rates varied by approximately twofold, with the lowest rate in Minnesota (268 deaths per 100,000) and the highest rate in Mississippi (482 deaths per 100,000). Rates improved the most in New York during the baseline period (−3.05% per year) and in New Jersey during the follow-up period (−2.87% per year), whereas Oklahoma ranked last in trends during both periods (−0.30%/y, baseline; +0.18%/y, follow-up). Trends improved the most in Connecticut, bending the curve downward by −1.03%; trends worsened the most in New Mexico, bending the curve upward by 1.21%. Discussion Current premature death rates, recent trends, and changes in trends vary by state in the United States. Policy makers can use these measures to evaluate the long-term population health impact of broad health care, behavioral, social, and economic investments in population health. PMID:24370109

Tachykinin receptors in rabbit airways--characterization by functional, autoradiographic and binding studies.

PubMed Central

Black, J. L.; Diment, L. M.; Alouan, L. A.; Johnson, P. R.; Armour, C. L.; Badgery-Parker, T.; Burcher, E.

1992-01-01

1. In many species, both NK1 and NK2 tachykinin receptors appear to be important in mediating the contraction of airway smooth muscle. We have examined the distribution and characterization of receptors for tachykinins in rabbit airways using functional length tension studies, autoradiography and radioligand binding studies. 2. Contractile responses to tachykinins were elicited in four different areas of the respiratory tree--trachea, and three progressively more distal areas of the right bronchus. The NK2 receptor-preferring agonists, neurokinin A (NKA), neuropeptide gamma (NP gamma) and the NK2-selective [Lys5 MeLeu9, Nle10]-NKA(4-10) [NKA (4-10) analogue] produced similar contraction in all four areas. Substance P (SP) and the NK1-selective [Sar9,Met(O2)11]-SP (Sar-SP) exhibited a marked location-dependence in the magnitude of contraction, producing minimal contraction in the trachea and more proximal bronchi with contractions becoming progressively larger in the more distal airways. Senktide (which is selective for the NK3 receptor) produced negligible contraction in all areas. 3. The NK2-selective antagonist, MDL29,913, was a weak antagonist of NKA and NKA(4-10) analogue. At a concentration of 2 microM, it produced a small but significant shift in the response curve to NKA and a greater shift (8 fold) in the curve to NKA(4-10) analogue, but it had no effect on responses to Sar-SP. The non peptide NK1 receptor antagonist, CP-96,345, was also unexpectedly weak in this preparation. The pD2 value for Sar-SP was decreased 27 fold by CP-96,345 at a concentration of 1 microM, without alteration in the maximum response.(ABSTRACT TRUNCATED AT 250 WORDS) Images Figure 4 PMID:1384914

Do Electrochemiluminescence Assays Improve Prediction of Time to Type 1 Diabetes in Autoantibody-Positive TrialNet Subjects?

PubMed Central

Fouts, Alexandra; Pyle, Laura; Yu, Liping; Miao, Dongmei; Michels, Aaron; Krischer, Jeffrey; Sosenko, Jay; Gottlieb, Peter

2016-01-01

OBJECTIVE To explore whether electrochemiluminescence (ECL) assays can help improve prediction of time to type 1 diabetes in the TrialNet autoantibody-positive population. RESEARCH DESIGN AND METHODS TrialNet subjects who were positive for one or more autoantibodies (microinsulin autoantibody, GAD65 autoantibody [GADA], IA-2A, and ZnT8A) with available ECL-insulin autoantibody (IAA) and ECL-GADA data at their initial visit were analyzed; after a median follow-up of 24 months, 177 of these 1,287 subjects developed diabetes. RESULTS Univariate analyses showed that autoantibodies by radioimmunoassays (RIAs), ECL-IAA, ECL-GADA, age, sex, number of positive autoantibodies, presence of HLA DR3/4-DQ8 genotype, HbA1c, and oral glucose tolerance test (OGTT) measurements were all significantly associated with progression to diabetes. Subjects who were ECL positive had a risk of progression to diabetes within 6 years of 58% compared with 5% for the ECL-negative subjects (P < 0.0001). Multivariate Cox proportional hazards models were compared, with the base model including age, sex, OGTT measurements, and number of positive autoantibodies by RIAs. The model with positivity for ECL-GADA and/or ECL-IAA was the best, and factors that remained significantly associated with time to diabetes were area under the curve (AUC) C-peptide, fasting C-peptide, AUC glucose, number of positive autoantibodies by RIAs, and ECL positivity. Adding ECL to the Diabetes Prevention Trial risk score (DPTRS) improved the receiver operating characteristic curves with AUC of 0.83 (P < 0.0001). CONCLUSIONS ECL assays improved the ability to predict time to diabetes in these autoantibody-positive relatives at risk for developing diabetes. These findings might be helpful in the design and eligibility criteria for prevention trials in the future. PMID:27456836

Do Electrochemiluminescence Assays Improve Prediction of Time to Type 1 Diabetes in Autoantibody-Positive TrialNet Subjects?

PubMed

Fouts, Alexandra; Pyle, Laura; Yu, Liping; Miao, Dongmei; Michels, Aaron; Krischer, Jeffrey; Sosenko, Jay; Gottlieb, Peter; Steck, Andrea K

2016-10-01

To explore whether electrochemiluminescence (ECL) assays can help improve prediction of time to type 1 diabetes in the TrialNet autoantibody-positive population. TrialNet subjects who were positive for one or more autoantibodies (microinsulin autoantibody, GAD65 autoantibody [GADA], IA-2A, and ZnT8A) with available ECL-insulin autoantibody (IAA) and ECL-GADA data at their initial visit were analyzed; after a median follow-up of 24 months, 177 of these 1,287 subjects developed diabetes. Univariate analyses showed that autoantibodies by radioimmunoassays (RIAs), ECL-IAA, ECL-GADA, age, sex, number of positive autoantibodies, presence of HLA DR3/4-DQ8 genotype, HbA1c, and oral glucose tolerance test (OGTT) measurements were all significantly associated with progression to diabetes. Subjects who were ECL positive had a risk of progression to diabetes within 6 years of 58% compared with 5% for the ECL-negative subjects (P < 0.0001). Multivariate Cox proportional hazards models were compared, with the base model including age, sex, OGTT measurements, and number of positive autoantibodies by RIAs. The model with positivity for ECL-GADA and/or ECL-IAA was the best, and factors that remained significantly associated with time to diabetes were area under the curve (AUC) C-peptide, fasting C-peptide, AUC glucose, number of positive autoantibodies by RIAs, and ECL positivity. Adding ECL to the Diabetes Prevention Trial risk score (DPTRS) improved the receiver operating characteristic curves with AUC of 0.83 (P < 0.0001). ECL assays improved the ability to predict time to diabetes in these autoantibody-positive relatives at risk for developing diabetes. These findings might be helpful in the design and eligibility criteria for prevention trials in the future. © 2016 by the American Diabetes Association.

Basic fibroblast growth factor in an animal model of spontaneous mammary tumor progression.

PubMed

Kao, Steven; Mo, Jeffrey; Baird, Andrew; Eliceiri, Brian P

2012-06-01

Although basic fibroblast growth factor (FGF2) was the first pro-angiogenic molecule discovered, it has numerous activities on the growth and differentiation of non-vascular cell types. FGF2 is both stimulatory and inhibitory, depending on the cell type evaluated, the experimental design used and the context in which it is tested. Here, we investigated the effects of manipulating endogenous FGF2 on the development of mammary cancer to determine whether its endogenous contribution in vivo is pro- or anti-tumorigenic. Specifically, we examined the effects of FGF2 gene dosing in a cross between a spontaneous breast tumor model (PyVT+ mice) and FGF2-/- (FGF KO) mice. Using these mice, the onset and progression of mammary tumors was determined. As predicted, female FGF2 WT mice developed mammary tumors starting around 60 days after birth and by 80 days, 100% of FGF2 WT female mice had mammary tumors. In contrast, 80% of FGF2 KO female mice had no palpable tumors until nearly three weeks later (85 days) at times when 100% of the WT cohort was tumor positive. All FGF KO mice were tumor-bearing by 115 days. When we compared the onset of mammary tumor development and the tumor progression curves between FGF het and FGF KO mice, we observed a difference, which suggested a gene dosing effect. Analysis of the tumors demonstrated that there were significant differences in tumor size depending on FGF2 status. The delay in tumor onset supports a functional role for FGF2 in mammary tumor progression, but argues against an essential role for FGF2 in overall mammary tumor progression.

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

Yeung, Timothy P C; Robarts Research Institute, The University of Western Ontario, Ontario, Canada, N6A 5B7; Department of Medical Biophysics, The University of Western Ontario, Ontario, Canada, N6A 5C1

Introduction: This study aimed to explore the potential for computed tomography (CT) perfusion and 18-Fluorodeoxyglucose positron emission tomography (FDG-PET) in predicting sites of future progressive tumour on a voxel-by-voxel basis after radiotherapy and chemotherapy. Methods: Ten patients underwent pre-radiotherapy magnetic resonance (MR), FDG-PET and CT perfusion near the end of radiotherapy and repeated post-radiotherapy follow-up MR scans. The relationships between these images and tumour progression were assessed using logistic regression. Cross-validation with receiver operating characteristic (ROC) analysis was used to assess the value of these images in predicting sites of tumour progression. Results: Pre-radiotherapy MR-defined gross tumour; near-end-of-radiotherapy CT-defined enhancingmore » lesion; CT perfusion blood flow (BF), blood volume (BV) and permeability-surface area (PS) product; FDG-PET standard uptake value (SUV); and SUV:BF showed significant associations with tumour progression on follow-up MR imaging (P < 0.0001). The mean sensitivity (±standard deviation), specificity and area under the ROC curve (AUC) of PS were 0.64 ± 0.15, 0.74 ± 0.07 and 0.72 ± 0.12 respectively. This mean AUC was higher than that of the pre-radiotherapy MR-defined gross tumour and near-end-of-radiotherapy CT-defined enhancing lesion (both AUCs = 0.6 ± 0.1, P ≤ 0.03). The multivariate model using BF, BV, PS and SUV had a mean AUC of 0.8 ± 0.1, but this was not significantly higher than the PS only model. Conclusion: PS is the single best predictor of tumour progression when compared to other parameters, but voxel-based prediction based on logistic regression had modest sensitivity and specificity.« less

Radiomics biomarkers for accurate tumor progression prediction of oropharyngeal cancer

NASA Astrophysics Data System (ADS)

Hadjiiski, Lubomir; Chan, Heang-Ping; Cha, Kenny H.; Srinivasan, Ashok; Wei, Jun; Zhou, Chuan; Prince, Mark; Papagerakis, Silvana

2017-03-01

Accurate tumor progression prediction for oropharyngeal cancers is crucial for identifying patients who would best be treated with optimized treatment and therefore minimize the risk of under- or over-treatment. An objective decision support system that can merge the available radiomics, histopathologic and molecular biomarkers in a predictive model based on statistical outcomes of previous cases and machine learning may assist clinicians in making more accurate assessment of oropharyngeal tumor progression. In this study, we evaluated the feasibility of developing individual and combined predictive models based on quantitative image analysis from radiomics, histopathology and molecular biomarkers for oropharyngeal tumor progression prediction. With IRB approval, 31, 84, and 127 patients with head and neck CT (CT-HN), tumor tissue microarrays (TMAs) and molecular biomarker expressions, respectively, were collected. For 8 of the patients all 3 types of biomarkers were available and they were sequestered in a test set. The CT-HN lesions were automatically segmented using our level sets based method. Morphological, texture and molecular based features were extracted from CT-HN and TMA images, and selected features were merged by a neural network. The classification accuracy was quantified using the area under the ROC curve (AUC). Test AUCs of 0.87, 0.74, and 0.71 were obtained with the individual predictive models based on radiomics, histopathologic, and molecular features, respectively. Combining the radiomics and molecular models increased the test AUC to 0.90. Combining all 3 models increased the test AUC further to 0.94. This preliminary study demonstrates that the individual domains of biomarkers are useful and the integrated multi-domain approach is most promising for tumor progression prediction.

Wind Power Electricity: The Bigger the Turbine, The Greener the Electricity?

PubMed Central

2012-01-01

Wind energy is a fast-growing and promising renewable energy source. The investment costs of wind turbines have decreased over the years, making wind energy economically competitive to conventionally produced electricity. Size scaling in the form of a power law, experience curves and progress rates are used to estimate the cost development of ever-larger turbines. In life cycle assessment, scaling and progress rates are seldom applied to estimate the environmental impacts of wind energy. This study quantifies whether the trend toward larger turbines affects the environmental profile of the generated electricity. Previously published life cycle inventories were combined with an engineering-based scaling approach as well as European wind power statistics. The results showed that the larger the turbine is, the greener the electricity becomes. This effect was caused by pure size effects of the turbine (micro level) as well as learning and experience with the technology over time (macro level). The environmental progress rate was 86%, indicating that for every cumulative production doubling, the global warming potential per kWh was reduced by 14%. The parameters, hub height and rotor diameter were identified as Environmental Key Performance Indicators that can be used to estimate the environmental impacts for a generic turbine. PMID:22475003

Wind power electricity: the bigger the turbine, the greener the electricity?

PubMed

Caduff, Marloes; Huijbregts, Mark A J; Althaus, Hans-Joerg; Koehler, Annette; Hellweg, Stefanie

2012-05-01

Wind energy is a fast-growing and promising renewable energy source. The investment costs of wind turbines have decreased over the years, making wind energy economically competitive to conventionally produced electricity. Size scaling in the form of a power law, experience curves and progress rates are used to estimate the cost development of ever-larger turbines. In life cycle assessment, scaling and progress rates are seldom applied to estimate the environmental impacts of wind energy. This study quantifies whether the trend toward larger turbines affects the environmental profile of the generated electricity. Previously published life cycle inventories were combined with an engineering-based scaling approach as well as European wind power statistics. The results showed that the larger the turbine is, the greener the electricity becomes. This effect was caused by pure size effects of the turbine (micro level) as well as learning and experience with the technology over time (macro level). The environmental progress rate was 86%, indicating that for every cumulative production doubling, the global warming potential per kWh was reduced by 14%. The parameters, hub height and rotor diameter were identified as Environmental Key Performance Indicators that can be used to estimate the environmental impacts for a generic turbine. © 2012 American Chemical Society

Marginal Structural Cox Models for Estimating the Association Between β-Interferon Exposure and Disease Progression in a Multiple Sclerosis Cohort

PubMed Central

Karim, Mohammad Ehsanul; Gustafson, Paul; Petkau, John; Zhao, Yinshan; Shirani, Afsaneh; Kingwell, Elaine; Evans, Charity; van der Kop, Mia; Oger, Joel; Tremlett, Helen

2014-01-01

Longitudinal observational data are required to assess the association between exposure to β-interferon medications and disease progression among relapsing-remitting multiple sclerosis (MS) patients in the “real-world” clinical practice setting. Marginal structural Cox models (MSCMs) can provide distinct advantages over traditional approaches by allowing adjustment for time-varying confounders such as MS relapses, as well as baseline characteristics, through the use of inverse probability weighting. We assessed the suitability of MSCMs to analyze data from a large cohort of 1,697 relapsing-remitting MS patients in British Columbia, Canada (1995–2008). In the context of this observational study, which spanned more than a decade and involved patients with a chronic yet fluctuating disease, the recently proposed “normalized stabilized” weights were found to be the most appropriate choice of weights. Using this model, no association between β-interferon exposure and the hazard of disability progression was found (hazard ratio = 1.36, 95% confidence interval: 0.95, 1.94). For sensitivity analyses, truncated normalized unstabilized weights were used in additional MSCMs and to construct inverse probability weight-adjusted survival curves; the findings did not change. Additionally, qualitatively similar conclusions from approximation approaches to the weighted Cox model (i.e., MSCM) extend confidence in the findings. PMID:24939980

Theoretical and experimental investigation of design for multioptical-axis freeform progressive addition lenses

NASA Astrophysics Data System (ADS)

Xiang, HuaZhong; Chen, JiaBi; Zhu, TianFen; Wei, YeFei; Fu, DongXiang

2015-11-01

A freeform progressive addition lens (PAL) provides a good solution to correct presbyopia and prevent juvenile myopia by distributing pupils' optical powers of distance zone, near zone, and intermediate zone and is more widely adopted in the present optometric study. However, there is still a lack of a single-optical-axis system for the design of a PAL. This paper focuses on the research for an approach for designing a freeform PAL. A multioptical-axis system based on real viewing conditions using the eyes is employed for the representation of the freeform surface. We filled small pupils in the intermediate zone as a progressive corridor and the distance- and near-vision portions were defined as the standard spherical surfaces delimited by quadratic curves. Three freeform PALs with a spherical surface as the front side and a freeform surface as the backside were designed. We demonstrate the fabrication and measurement technologies for the PAL surface using computer numerical control machine tools from Schneider Smart and a Visionix VM-2000 Lens Power Mapper. Surface power and astigmatic values were obtained. Preliminary results showed that the approach for the design and fabrication is helpful to advance the design procedure optimization and mass production of PALs in optometry.

A note on drillhole depths required for reliable heat flow determinations

USGS Publications Warehouse

Chapman, D.S.; Howell, J.; Sass, J.H.

1984-01-01

In general, there is a limiting depth in a drillhole above which the reliability of a single determination of heat flow decreases rapidly with decreasing depth and below which the statistical uncertainty of a heat flow determination does not change perceptibly with increasing depth. This feature has been established empirically for a test case comprising a group of twelve heat flow sites in the Republic of Zambia. The technique consists of constructing heat flow versus depth curves for individual sites by progressively discarding data from the lower part of the hole and recomputing heat flow from the remaining data. For the Zambian test case, the curves converge towards a uniform value of 67 ?? 3 mW m-2 when all available data are used, but values of heat flow calculated for shallow(< 100 m) parts of the same holes range from 45 to 95 mW m-2. The heat flow versus depth curves are enclosed by a perturbation envelope which has an amplitude of 40 mW m-2 at the surface and decreases linearly to the noise level at 190 m. For the test region of Zambia a depth of 170 m is needed to guarantee a heat flow measurement within ?? 10% of the background regional value. It is reasonable to expect that this depth will be shallower in some regions and deeper in others. Features of heat flow perturbation envelopes can be used as quantitative reliability indices for heat flow studies. ?? 1984.

Nonlinear Analysis and Post-Test Correlation for a Curved PRSEUS Panel

NASA Technical Reports Server (NTRS)

Gould, Kevin; Lovejoy, Andrew E.; Jegley, Dawn; Neal, Albert L.; Linton, Kim, A.; Bergan, Andrew C.; Bakuckas, John G., Jr.

2013-01-01

The Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) concept, developed by The Boeing Company, has been extensively studied as part of the National Aeronautics and Space Administration's (NASA s) Environmentally Responsible Aviation (ERA) Program. The PRSEUS concept provides a light-weight alternative to aluminum or traditional composite design concepts and is applicable to traditional-shaped fuselage barrels and wings, as well as advanced configurations such as a hybrid wing body or truss braced wings. Therefore, NASA, the Federal Aviation Administration (FAA) and The Boeing Company partnered in an effort to assess the performance and damage arrestments capabilities of a PRSEUS concept panel using a full-scale curved panel in the FAA Full-Scale Aircraft Structural Test Evaluation and Research (FASTER) facility. Testing was conducted in the FASTER facility by subjecting the panel to axial tension loads applied to the ends of the panel, internal pressure, and combined axial tension and internal pressure loadings. Additionally, reactive hoop loads were applied to the skin and frames of the panel along its edges. The panel successfully supported the required design loads in the pristine condition and with a severed stiffener. The panel also demonstrated that the PRSEUS concept could arrest the progression of damage including crack arrestment and crack turning. This paper presents the nonlinear post-test analysis and correlation with test results for the curved PRSEUS panel. It is shown that nonlinear analysis can accurately calculate the behavior of a PRSEUS panel under tension, pressure and combined loading conditions.

Waist circumference and insulin resistance: a cross-sectional study of Japanese men

PubMed Central

Tabata, Shinji; Yoshimitsu, Shinichiro; Hamachi, Tadamichi; Abe, Hiroshi; Ohnaka, Keizo; Kono, Suminori

2009-01-01

Background Visceral obesity is positively related to insulin resistance. The nature of the relationship between waist circumference and insulin resistance has not been known in Japanese populations. This study examined the relationship between waist circumference and insulin resistance and evaluated the optimal cutoff point for waist circumference in relation to insulin resistance in middle-aged Japanese men. Methods Study subjects included 4800 Japanese men aged 39 to 60 years. Insulin resistance was evaluated by the homeostasis model assessment of insulin resistance (HOMA-IR). The relationship of waist circumference with HOMA-IR was assessed by use of adjusted means of HOMA-IR and odds ratios of elevated HOMA-IR defined as the highest quintile (≥2.00). Receiver operating characteristics (ROC) curve analysis using Youden index and the area under curve (AUC) was employed to determine optimal cutoffs of waist circumference in relation to HOMA-IR. Results Adjusted geometric means of HOMA-IR and prevalence odds of elevated HOMA-IR were progressively higher with increasing levels of waist circumference. In the ROC curve analysis, the highest value of Youden index was obtained for a cutoff point of 85 cm in waist circumference across different values of HOMA-IR. Multiple logistic regression analysis also indicated that the AUC was consistently the largest for a waist circumference of 85 cm. Conclusion Waist circumference is linearly related to insulin resistance, and 85 cm in waist circumference is an optimal cutoff in predicting insulin resistance in middle-aged Japanese men. PMID:19138424

Determination of secondary flow morphologies by wavelet analysis in a curved artery model with physiological inflow

NASA Astrophysics Data System (ADS)

Bulusu, Kartik V.; Hussain, Shadman; Plesniak, Michael W.

2014-11-01

Secondary flow vortical patterns in arterial curvatures have the potential to affect several cardiovascular phenomena, e.g., progression of atherosclerosis by altering wall shear stresses, carotid atheromatous disease, thoracic aortic aneurysms and Marfan's syndrome. Temporal characteristics of secondary flow structures vis-à-vis physiological (pulsatile) inflow waveform were explored by continuous wavelet transform (CWT) analysis of phase-locked, two-component, two-dimensional particle image velocimeter data. Measurements were made in a 180° curved artery test section upstream of the curvature and at the 90° cross-sectional plane. Streamwise, upstream flow rate measurements were analyzed using a one-dimensional antisymmetric wavelet. Cross-stream measurements at the 90° location of the curved artery revealed interesting multi-scale, multi-strength coherent secondary flow structures. An automated process for coherent structure detection and vortical feature quantification was applied to large ensembles of PIV data. Metrics such as the number of secondary flow structures, their sizes and strengths were generated at every discrete time instance of the physiological inflow waveform. An autonomous data post-processing method incorporating two-dimensional CWT for coherent structure detection was implemented. Loss of coherence in secondary flow structures during the systolic deceleration phase is observed in accordance with previous research. The algorithmic approach presented herein further elucidated the sensitivity and dependence of morphological changes in secondary flow structures on quasiperiodicity and magnitude of temporal gradients in physiological inflow conditions.

An electron microscopy study of the diversity of Streptococcus sanguinis cells induced by lysozyme in vitro.

PubMed

Hao, Yuqing; Li, Li; Li, Wei; Zhou, Xuedong; Lu, Junjun

2010-01-01

Bacterial virulence could be altered by the antimicrobial agents of the host. Our aim was to identify the damage and survival of Streptococcus sanguinis induced by lysozymes in vitro and to analyse the potential of oral microorganisms to shirk host defences, which cause infective endocarditis. S. sanguinis ATCC 10556 received lysozyme at concentrations of 12.5, 25, 50 and 100 microg/ml. Cells were examined by electron microscopy. The survival was assessed by colony counting and construction of a growth curve. Challenged by lysozymes, cells mainly exhibited cell wall damage, which seemed to increase with increasing lysozyme concentration and longer incubation period in the presence of ions. Cells with little as well as apparent lesion were observed under the same treatment set, and anomalous stick and huge rotund bodies were occasionally observed. After the removal of the lysozyme, some damaged cells could be reverted to its original form with brain heart infusion (BHI), and their growth curve was similar to the control cells. After further incubation in BHI containing lysozyme, S. sanguinis cell damage stopped progressing, and their growth curve was also similar to the control cells. The results suggested that the S. sanguinis lesions caused by the lysozyme in the oral cavity may be nonhomogeneous and that some damaged cells could self-repair and survive. It also indicated that S. sanguinis with damaged cell walls may survive and be transmitted in the bloodstream.

Establishment of Biological Reference Intervals and Reference Curve for Urea by Exploratory Parametric and Non-Parametric Quantile Regression Models.

PubMed

Sarkar, Rajarshi

2013-07-01

The validity of the entire renal function tests as a diagnostic tool depends substantially on the Biological Reference Interval (BRI) of urea. Establishment of BRI of urea is difficult partly because exclusion criteria for selection of reference data are quite rigid and partly due to the compartmentalization considerations regarding age and sex of the reference individuals. Moreover, construction of Biological Reference Curve (BRC) of urea is imperative to highlight the partitioning requirements. This a priori study examines the data collected by measuring serum urea of 3202 age and sex matched individuals, aged between 1 and 80 years, by a kinetic UV Urease/GLDH method on a Roche Cobas 6000 auto-analyzer. Mann-Whitney U test of the reference data confirmed the partitioning requirement by both age and sex. Further statistical analysis revealed the incompatibility of the data for a proposed parametric model. Hence the data was non-parametrically analysed. BRI was found to be identical for both sexes till the 2(nd) decade, and the BRI for males increased progressively 6(th) decade onwards. Four non-parametric models were postulated for construction of BRC: Gaussian kernel, double kernel, local mean and local constant, of which the last one generated the best-fitting curves. Clinical decision making should become easier and diagnostic implications of renal function tests should become more meaningful if this BRI is followed and the BRC is used as a desktop tool in conjunction with similar data for serum creatinine.

Long-term echocardiographic follow-up of untreated 2+ functional tricuspid regurgitation in patients undergoing mitral valve surgery.

PubMed

Kusajima, Kunio; Fujita, Tomoyuki; Hata, Hiroki; Shimahara, Yusuke; Miura, Sayaka; Kobayashi, Junjiro

2016-07-01

Concomitant tricuspid valve surgery with mitral valve surgery is recommended for patients with severe functional tricuspid regurgitation (TR). However, the treatment for 2+ TR (mild TR) remains controversial. Here, we evaluated the long-term results of untreated 2+ TR in patients undergoing mitral valve surgery. We retrospectively reviewed the records of 96 patients with untreated 2+ TR among 885 patients who underwent mitral valve surgery from 2003 to 2010. Exclusion criteria were tricuspid valve surgery (TVS), emergency surgery, primary TR and pacemaker lead through the tricuspid valve. We assessed survival and freedom from heart failure. The freedom from 3+ (moderate) or 4+ (severe) TR was investigated by echocardiographic data at pre- and postoperative week 1, then at 1, 3, 5, 7 and 10 postoperative years, which were compared with those in patients who had 2+ TR preoperatively and underwent concomitant TVS in the same period (n = 47). The mean follow-up was 7.1 ± 2.7 years. There was no 30-day mortality. The survival rate was 97.5% at 5 years and 87.5% at 10 years. The independent risk factors for mortality were age (OR 1.2, P = 0.03) and left ventricular ejection fraction (OR 0.9, P = 0.03). Untreated 2+ TR improved transiently within the first postoperative year (P < 0.001), but progressed again in the mid- to long term. Freedom from ≥3+ TR was 64.2% at 5 years and 46.7% at 10 years, which was significantly lower than that from ≥3+ TR in patients who underwent concomitant TVS (P = 0.006). The independent risk factors for TR progression (≥3 + TR) were age (OR 1.1, P = 0.005), atrial fibrillation (OR 2.2, P = 0.04) and tricuspid annular diameter (TAD) index (mm/m(2); OR 1.1, P = 0.02). Receiver operating characteristic curves showed that the optimal TAD index cut-off value was 21.0 for long-term survival [area under the curve (AUC) = 0.72] and 21.2 for TR progression (AUC = 0.64). Although untreated, 2+ TR significantly improved after mitral valve surgery, it then progressed again in the mid- to long term. Therefore, concomitant TVS should be considered in patients with 2+ TR who have dilated tricuspid annulus or atrial fibrillation, if feasible. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

DCE-MRI defined subvolumes of a brain metastatic lesion by principle component analysis and fuzzy-c-means clustering for response assessment of radiation therapy

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

Farjam, Reza; Tsien, Christina I.; Lawrence, Theodore S.

Purpose: To develop a pharmacokinetic modelfree framework to analyze the dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) data for assessment of response of brain metastases to radiation therapy. Methods: Twenty patients with 45 analyzable brain metastases had MRI scans prior to whole brain radiation therapy (WBRT) and at the end of the 2-week therapy. The volumetric DCE images covering the whole brain were acquired on a 3T scanner with approximately 5 s temporal resolution and a total scan time of about 3 min. DCE curves from all voxels of the 45 brain metastases were normalized and then temporally aligned. Amore » DCE matrix that is constructed from the aligned DCE curves of all voxels of the 45 lesions obtained prior to WBRT is processed by principal component analysis to generate the principal components (PCs). Then, the projection coefficient maps prior to and at the end of WBRT are created for each lesion. Next, a pattern recognition technique, based upon fuzzy-c-means clustering, is used to delineate the tumor subvolumes relating to the value of the significant projection coefficients. The relationship between changes in different tumor subvolumes and treatment response was evaluated to differentiate responsive from stable and progressive tumors. Performance of the PC-defined tumor subvolume was also evaluated by receiver operating characteristic (ROC) analysis in prediction of nonresponsive lesions and compared with physiological-defined tumor subvolumes. Results: The projection coefficient maps of the first three PCs contain almost all response-related information in DCE curves of brain metastases. The first projection coefficient, related to the area under DCE curves, is the major component to determine response while the third one has a complimentary role. In ROC analysis, the area under curve of 0.88 ± 0.05 and 0.86 ± 0.06 were achieved for the PC-defined and physiological-defined tumor subvolume in response assessment. Conclusions: The PC-defined subvolume of a brain metastasis could predict tumor response to therapy similar to the physiological-defined one, while the former is determined more rapidly for clinical decision-making support.« less

Raining a magma ocean: Thermodynamics of rocky planets after a giant impact

NASA Astrophysics Data System (ADS)

Stewart, S. T.; Lock, S. J.; Caracas, R.

2017-12-01

Rocky planets in exoplanetary systems have equilibrium temperatures up to a few 1000 K. The thermal evolution after a giant impact is sensitive to the equilibrium temperature. Post-impact rocky bodies are thermally stratified, with cooler, lower-entropy silicate overlain by vaporized, higher-entropy silicate. The radii of impact-vaporized rocky planets are much larger than the radii of equivalent condensed bodies. Furthermore, after some high-energy, high-angular momentum collisions, the post-impact body exceeds the corotation limit for a rocky planet and forms a synestia. Initially, volatiles and silicates are miscible at the high temperatures of the outer layer. If the equilibrium temperature with the star is lower than the silicate condensation temperature ( 2000 K), silicate droplets form at the photosphere and fall while volatile components remain in the vapor. Radiation and turbulent convection cool the vapor outer layer to the silicate vapor curve. A distinct magma ocean forms as the thermal profile crosses the silicate vapor curve and the critical curves for the volatiles. Near the temperatures and pressures of the critical curves, volatiles and silicates are partially soluble in each other. As the system continues cooling, the volatile vapor and silicate liquid separate toward the end member compositions, which are determined by the equilibrium temperature and the total vapor pressure of volatiles. If the equilibrium temperature with the star is near or above the condensation temperature for silicates, there would be limited condensation at the photosphere. Initially, the cooler lower mantle would slowly, diffusively equilibrate with the hotter upper mantle. In some cases, the thermal profile may cross the silicate vapor curve in the middle of the silicate layer, producing a silicate rain layer within the body. With continued evolution toward an adiabatic thermal profile, the body would separate into a silicate liquid layer underlying a silicate-volatile vapor layer. As the hottest rocky planets become tidally locked to their star, cooling progresses asymmetrically. The timing and degree of differentiation of rocky planets into silicate mantles and volatile atmospheres depends on the thermal evolution of vaporized rocky planets and may vary widely with equilibrium temperature.

DCE-MRI defined subvolumes of a brain metastatic lesion by principle component analysis and fuzzy-c-means clustering for response assessment of radiation therapy

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

Farjam, Reza; Tsien, Christina I.; Lawrence, Theodore S.

2014-01-15

Purpose: To develop a pharmacokinetic modelfree framework to analyze the dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) data for assessment of response of brain metastases to radiation therapy. Methods: Twenty patients with 45 analyzable brain metastases had MRI scans prior to whole brain radiation therapy (WBRT) and at the end of the 2-week therapy. The volumetric DCE images covering the whole brain were acquired on a 3T scanner with approximately 5 s temporal resolution and a total scan time of about 3 min. DCE curves from all voxels of the 45 brain metastases were normalized and then temporally aligned. Amore » DCE matrix that is constructed from the aligned DCE curves of all voxels of the 45 lesions obtained prior to WBRT is processed by principal component analysis to generate the principal components (PCs). Then, the projection coefficient maps prior to and at the end of WBRT are created for each lesion. Next, a pattern recognition technique, based upon fuzzy-c-means clustering, is used to delineate the tumor subvolumes relating to the value of the significant projection coefficients. The relationship between changes in different tumor subvolumes and treatment response was evaluated to differentiate responsive from stable and progressive tumors. Performance of the PC-defined tumor subvolume was also evaluated by receiver operating characteristic (ROC) analysis in prediction of nonresponsive lesions and compared with physiological-defined tumor subvolumes. Results: The projection coefficient maps of the first three PCs contain almost all response-related information in DCE curves of brain metastases. The first projection coefficient, related to the area under DCE curves, is the major component to determine response while the third one has a complimentary role. In ROC analysis, the area under curve of 0.88 ± 0.05 and 0.86 ± 0.06 were achieved for the PC-defined and physiological-defined tumor subvolume in response assessment. Conclusions: The PC-defined subvolume of a brain metastasis could predict tumor response to therapy similar to the physiological-defined one, while the former is determined more rapidly for clinical decision-making support.« less

Evaluation of keratoconus progression.

PubMed

Shajari, Mehdi; Steinwender, Gernot; Herrmann, Kim; Kubiak, Kate Barbara; Pavlovic, Ivana; Plawetzki, Elena; Schmack, Ingo; Kohnen, Thomas

2018-06-01

To define variables for the evaluation of keratoconus progression and to determine cut-off values. In this retrospective cohort study (2010-2016), 265 eyes of 165 patients diagnosed with keratoconus underwent two Scheimpflug measurements (Pentacam) that took place 1 year apart ±3 months. Variables used for keratoconus detection were evaluated for progression and a correlation analysis was performed. By logistic regression analysis, a keratoconus progression index (KPI) was defined. Receiver-operating characteristic curve (ROC) analysis was performed and Youden Index calculated to determine cut-off values. Variables used for keratoconus detection showed a weak correlation with each other (eg, correlation r=0.245 between RPImin and Kmax, p<0.001). Therefore, we used parameters that took several variables into consideration (eg, D-index, index of surface variance, index for height asymmetry, KPI). KPI was defined by logistic regression and consisted of a Pachymin coefficient of -0.78 (p=0.001), a maximum elevation of back surface coefficient of 0.27 and coefficient of corneal curvature at the zone 3 mm away from the thinnest point on the posterior corneal surface of -12.44 (both p<0.001). The two variables with the highest Youden Index in the ROC analysis were D-index and KPI: D-index had a cut-off of 0.4175 (70.6% sensitivity) and Youden Index of 0.606. Cut-off for KPI was -0.78196 (84.7% sensitivity) and a Youden Index of 0.747; both 90% specificity. Keratoconus progression should be defined by evaluating parameters that consider several corneal changes; we suggest D-index and KPI to detect progression. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Autoantibodies against AT1 and α1-adrenergic receptors predict arterial stiffness progression in normotensive subjects over a 5-year period.

PubMed

Li, Gang; Cao, Zhe; Wu, Xiao-Wei; Wu, Hui-Kun; Ma, Yi; Wu, Bin; Wang, Wei-Qing; Cheng, Jian; Zhou, Zi-Hua; Tu, Yuan-Chao

2017-12-15

Arterial stiffness is an independent indicator of cardiovascular risk. Autoantibodies (AAs) against angiotensin AT 1 receptor (AT 1 -AAs) and α 1 -adrenergic receptor (α 1 -AAs) are important in the pathogenesis of hypertension. We identified the types of AT 1 -AAs and α 1 -AAs in normotensive subjects, with the aim of determining whether these antibodies predict aortic stiffness progression. Carotid-femoral pulse wave velocity (cf-PWV) was used to measure aortic stiffness. Overall, 816 subjects (71% of those invited) underwent a medical examination and evaluation of aortic stiffness. The types of AT 1 -AAs and α 1 -AAs were measured at baseline. Meanwhile, plasma renin, angiotensin II (Ang II), and norepinephrine (NE) concentrations were measured at baseline and follow-up. Baseline mean cf-PWV was 9.90 ± 0.84 m/s and follow-up was 10.51 ± 1.12 m/s. The annualized ΔPWV was 0.12 ± 0.08 m/s/year. At the end of follow-up, 129 normotensive subjects developed hypertension and 144 subjects had PWV progression. After adjustment for covariates, AA type was independently associated with ΔPWV, annualized ΔPWV, and abnormal PWV. In our study, the risk of developing hypertension (RR =2.028, 95% CI: 1.227-3.351, P =0.006) and PWV progression (RR =2.910, 95% CI: 1.612-5.253, P <0.001) in AA-positive subjects was significantly higher than that in AA-negative subjects. Receiver operating characteristic (ROC) curve showed AA had an identify power to discriminate subjects with or without PWV and hypertension progression. We have shown for the first time that the types of A 1 -AAs and α 1 -AAs are independent predictors for aortic stiffness progression in normotensive subjects. Our data collectively support the utility of these AAs as potential markers of aortic stiffness. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

Can Non-HLA Single Nucleotide Polymorphisms Help Stratify Risk in TrialNet Relatives at Risk for Type 1 Diabetes?

PubMed

Steck, Andrea K; Xu, Ping; Geyer, Susan; Redondo, Maria J; Antinozzi, Peter; Wentworth, John M; Sosenko, Jay; Onengut-Gumuscu, Suna; Chen, Wei-Min; Rich, Stephen S; Pugliese, Alberto

2017-08-01

Genome-wide association studies identified >50 type 1 diabetes (T1D) associated non-human leukocyte antigens (non-HLA) loci. The purpose of this study was to assess the contribution of non-HLA single nucleotide polymorphisms (SNPs) to risk of disease progression. The TrialNet Pathway to Prevention Study follows relatives of T1D patients for development of autoantibodies (Abs) and T1D. Using the Immunochip, we analyzed 53 diabetes-associated, non-HLA SNPs in 1016 Ab-positive, at-risk non-Hispanic white relatives. Effect of SNPs on the development of multiple Abs and T1D. Cox proportional analyses included all substantial non-HLA SNPs, HLA genotypes, relationship to proband, sex, age at initial screening, initial Ab type, and number. Factors involved in progression from single to multiple Abs included age at screening, relationship to proband, HLA genotypes, and rs3087243 (cytotoxic T lymphocyte antigen-4). Significant factors for diabetes progression included age at screening, Ab number, HLA genotypes, rs6476839 [GLIS family zinc finger 3 (GLIS3)], and rs3184504 [SH2B adaptor protein 3 (SH2B3)]. When glucose area under the curve (AUC) was included, factors involved in disease progression included glucose AUC, age at screening, Ab number, relationship to proband, HLA genotypes, rs6476839 (GLIS3), and rs7221109 (CCR7). In stratified analyses by age, glucose AUC, age at screening, sibling, HLA genotypes, rs6476839 (GLIS3), and rs4900384 (C14orf64) were significantly associated with progression to diabetes in participants <12 years old, whereas glucose AUC, sibling, rs3184504 (SH2B3), and rs4900384 (C14orf64) were significant in those ≥12. In conclusion, we identified five non-HLA SNPs associated with increased risk of progression from Ab positivity to disease that may improve risk stratification for prevention trials. Copyright © 2017 by the Endocrine Society

Serum thyrotrophin at baseline predicts the natural course of subclinical hyperthyroidism.

PubMed

Das, G; Ojewuyi, T A; Baglioni, P; Geen, J; Premawardhana, L D; Okosieme, O E

2012-07-01

Optimal therapeutic strategies for subclinical hyperthyroidism are undecided. Overt disease develops in a minority of cases, but the risk factors for progression remain unclear. We examined whether a baseline thyrotrophin (TSH) predicted progression to overt hyperthyroidism in asymptomatic individuals with subclinical hyperthyroidism. This was a retrospective study of 323 patients with subclinical hyperthyroidism seen in our institution from 2003 to 2010 (mean age 71 years, males 26·9%, females 73·1%, mean follow-up duration 32 months, range 6-93 months). Serum TSH and free thyroxine (FT4) were documented at baseline and during follow-up. After excluding individuals with nonthyroid causes of low TSH, patients were grouped according to initial TSH as: TSH 0·10-0·39 mU/l (grade I) and TSH < 0·10 mU/l (grade II). Only 38 patients (11·8%) developed overt hyperthyroidism with annual progression rates of 0·6-3·7%. Most patients reverted to normal thyroid status (31·6%) or remained subclinically hyperthyroid (56·7%). Progression to frank hyperthyroidism was higher in grade II than in grade I patients (20·3% vs 6·8%, P < 0·001, Chi square test). Kaplan-Meier curves showed faster progression rates in grade II than grade I (P < 0·001, log rank test). In stepwise multivariate Cox regression analysis, TSH < 0·1 mU/l was associated with overt hyperthyroidism (hazard ratio 3·4, confidence interval 1·6-7·0), whereas age, gender, FT4 and aetiological diagnosis were not associated with hyperthyroidism. Thyrotrophin predicts overt hyperthyroidism in asymptomatic individuals with subclinical hyperthyroidism. Patients with TSH < 0·10 mU/l have a higher risk of progressing to hyperthyroidism than those with TSH 0·10-0·39 mU/l. © 2012 Blackwell Publishing Ltd.

Transverse field focused system

DOEpatents

Anderson, Oscar A.

1986-01-01

A transverse field focused (TFF) system for transport or acceleration of an intense sheet beam of negative ions in which a serial arrangement of a plurality of pairs of concentric cylindrical-arc electrodes is provided. Acceleration of the sheet beam can be achieved by progressively increasing the mean electrode voltage of successive electrode pairs. Because the beam is curved by the electrodes, the system can be designed to transport the beam through a maze passage which is baffled to prevent line of sight therethrough. Edge containment of the beam can be achieved by shaping the side edges of the electrodes to produce an electric force vector directed inwardly from the electrode edges.

Optical Observation of Low Mass X-Ray Binary J1753.4-0126

NASA Astrophysics Data System (ADS)

Paez, Aurelio; Mason, Paul A.; Robinson, E. L.

2011-10-01

We conducted optical observations of the black hole candidate J1753.4-0126 with the 82 inch (2.1 m) Otto Struve Telescope at the McDonald Observatory. A total of 20 nights of data were collected from May 2010 through June 2011. Data was reduced using the Interactive Reduction and Analysis Facility (IRAF). We present the resulting light curves. We discuss our progress in this analysis, which uses a phase dispersion minimization code in order to find periodicity. This research is supported by a National Science Foundation Partnership in Astronomy and Astrophysics Research and Education (PAARE) grant to the University of Texas at El Paso.

An experimental investigation on the three-point bending behavior of composite laminate

NASA Astrophysics Data System (ADS)

A, Azzam; W, Li

2014-08-01

The response of composite laminate structure to three-point bending load was investigated by subjecting two types of stacking sequences of composite laminate structure by using electronic universal tester (Type: WDW-20) machine. Optical microscope was selected in order to characterize bending damage, delamination, and damage shapes in composite laminate structures. The results showed that the [0/90/-45/45]2s exhibits a brittle behavior, while other laminates exhibit a progressive failure mode consisting of fiber failure, debonding (splitting), and delamination. The [45/45/90/0]2s laminate has a highly nonlinear load- displacement curve due to compressive yielding.

Lead optimization attrition analysis (LOAA): a novel and general methodology for medicinal chemistry.

PubMed

Munson, Mark; Lieberman, Harvey; Tserlin, Elina; Rocnik, Jennifer; Ge, Jie; Fitzgerald, Maria; Patel, Vinod; Garcia-Echeverria, Carlos

2015-08-01

Herein, we report a novel and general method, lead optimization attrition analysis (LOAA), to benchmark two distinct small-molecule lead series using a relatively unbiased, simple technique and commercially available software. We illustrate this approach with data collected during lead optimization of two independent oncology programs as a case study. Easily generated graphics and attrition curves enabled us to calibrate progress and support go/no go decisions on each program. We believe that this data-driven technique could be used broadly by medicinal chemists and management to guide strategic decisions during drug discovery. Copyright © 2015 Elsevier Ltd. All rights reserved.

Determination of the kinetics of degradation of 13-cis-retinoic acid and all-trans-retinoic acid in solution.

PubMed

Tan, X; Meltzer, N; Lindenbaum, S

1993-09-01

The degradations of 13-cis-retinoic acid and all-trans-retinoic acid in an organic solvent were determined with an HPLC assay. The degradation curves at 70, 50 and 37 degrees C all showed autocatalytic characteristics for both isomers. For this kind of complex reaction, the usual method cannot be used to estimate the shelf-lives and half-lives at room temperature. In this work a new method was developed to directly calculate the shelf-lives and half-lives. From this equation the activation energy was found to change as the multiple step reaction progressed.

UV-induced lethal sectoring and pure mutant clones in yeast.

PubMed

Hannan, M A; Duck, P; Nasim, A

1976-08-01

The induction of lethal sectoring and pure mutant clones by ultraviolet light has been studied in a homogeneous G1 population of Saccharomyces cerevisiae grown in a normal growth medium. At the lowest UV dose of 250 ergs, which corresponds to a shoulder in the survival curve, all mutants appeared as pure clones. At higher doses the frequency of mosaic mutants progressively increased. These results indicate a relationship between the highest frequency of complete mutants and the maximum repair activity. In addition, the frequency of lethal sectoring at all doses tested was too low to account for the origin of pure mutant clones.

The long-term evolution of the X-ray pulsar XTE J1814-338: A receding jet contribution to the quiescent optical emission?

NASA Astrophysics Data System (ADS)

Baglio, M. C.; D'Avanzo, P.; Muñoz-Darias, T.; Breton, R. P.; Campana, S.

2013-11-01

Aims: We present a study of the quiescent optical counterpart of the accreting millisecond X-ray pulsar XTE J1814-338 that is aimed at unveiling the different components, which contribute to the quiescent optical emission of the system. Methods: We carried out multiband (BVR) orbital phase-resolved photometry of the system using the ESO Very Large Telescope (VLT) that is equipped with the FORS2 camera, covering about 70% of the 4.3 hour orbital period. Results: The optical light curves are consistent with a sinusoidal variability that are modulated with an orbital period with a semi-amplitude of 0.5-0.7 mag. They show evidence of a strongly irradiated companion star, which agrees with previous findings for this system. However, the observed colours cannot be accounted for by the companion star alone, suggesting the presence of an accretion disc during quiescence. The system seems to be fainter in all analysed bands compared to previous observations. The R band light curve displays a possible phase offset with respect to the B and V band. Through a combined fit of the multi-band light curve performed with a Markov chain Monte Carlo technique, we derive constraints on the companion star, disc fluxes, system distance, and companion star mass. Conclusions: The irradiation luminosity required to account for the observed day-side temperature of the companion star is consistent with the spin-down luminosity of a millisecond radio pulsar. Compared to our data with previous observations, which were collected over 5 years, the flux decrease and spectral evolution of the observed quiescent optical emission cannot be satisfactorily explained with the combined contribution of an irradiated companion star and of an accretion disc alone. The observed progressive flux decrease as the system gets bluer could be due to a continuum component that evolves towards a lower, bluer spectrum. While most of the continuum component is likely due to the disc, we do not expect it to become bluer in quiescence. Hence, we hypothesize that an additional component, such as synchrotron emission from a jet was significantly contributing in the data obtained earlier during quiescence and then progressively fading or moving its break frequency towards longer wavelengths. Based on observations made with ESO Telescopes at the Paranal Observatory under programme ID 383.D-0730(A).

Screening for Adolescent Idiopathic Scoliosis: Evidence Report and Systematic Review for the US Preventive Services Task Force.

PubMed

Dunn, John; Henrikson, Nora B; Morrison, Caitlin C; Blasi, Paula R; Nguyen, Matt; Lin, Jennifer S

2018-01-09

Adolescent idiopathic scoliosis (AIS), a spinal curvature of 10° or more, is the most common form of scoliosis, with a prevalence of 1% to 3%. Curves progress in approximately two-thirds of patients with AIS before skeletal maturity, and large curves (>50°) may be associated with adverse health outcomes. To systematically review evidence on benefits and harms of AIS screening for the US Preventive Services Task Force (USPSTF). Cochrane Central Register of Controlled Trials, MEDLINE, ERIC, PubMed, CINAHL, and relevant systematic reviews were searched for studies published from January 1966 to October 20, 2016; studies included in a previous USPSTF report were also reviewed. Surveillance was conducted through July 24, 2017. Fair- and good-quality studies that evaluated the accuracy of screening children and adolescents aged 10 to 18 years for AIS, the benefits of AIS treatment, the harms of AIS screening or treatment, or long-term health outcomes. Two investigators independently reviewed abstracts and full-text articles and extracted data into evidence tables. Results were qualitatively summarized. Health outcomes and spinal curvature in adolescence and adulthood, accuracy of screening for AIS, any harm of AIS screening or treatment. Fourteen studies (N = 448 276) in 26 articles were included. Accuracy of AIS screening was highest (93.8% sensitivity; 99.2% specificity) in a cohort study of a clinic-based program using forward bend test, scoliometer, and Moiré topography screening (n = 306 082); accuracy was lower in cohort studies of 6 programs using fewer modalities (n = 141 161). Four controlled studies (n = 587) found evidence for benefit of bracing on curve progression compared with controls. A randomized clinical trial and a nonrandomized trial of exercise treatment (N = 184) found favorable reductions in Cobb angle of 0.67° to 4.9° in the intervention group compared with increases of 1.38° to 2.8° in the control group. Two cohort studies (n = 339) on long-term outcomes found that braced participants reported more negative treatment experience and body appearance compared with surgically treated or untreated participants. A study that combined a randomized clinical trial and cohort design (n = 242) reported harms of bracing, which included skin problems on the trunk and nonback body pains. There was no evidence on the effect of AIS screening on adult health outcomes. Screening can detect AIS. Bracing and possibly exercise treatment can interrupt or slow progression of curvature in adolescence. However, there is little or no evidence on long-term outcomes for AIS treated in adolescence, the association between curvature at skeletal maturity and adult health outcomes, the harms of AIS screening or treatment, or the effect of AIS screening on adult health outcomes.

Repulsive guidance cue semaphorin 3A in urine predicts the progression of acute kidney injury in adult patients from a mixed intensive care unit.

PubMed

Doi, Kent; Noiri, Eisei; Nangaku, Masaomi; Yahagi, Naoki; Jayakumar, Calpurnia; Ramesh, Ganesan

2014-01-01

Predicting the development of acute kidney injury (AKI) in the critical care setting is challenging. Although several biomarkers showed somewhat satisfactory performance for detecting established AKI even in a heterogeneous disease-oriented population, identification of new biomarkers that predict the development of AKI accurately is urgently required. A single-center prospective observational cohort study was undertaken to evaluate for the first time the reliability of the newly identified biomarker semaphorin 3A for AKI diagnosis in heterogeneous intensive care unit populations. In addition to five urinary biomarkers of L-type fatty acid-binding protein (L-FABP), neutrophil gelatinase-associated lipocalin (NGAL), IL-18, albumin and N-acetyl-β-d-glucosaminidase (NAG), urinary semaphorin 3A was measured at intensive care unit (ICU) admission. Three hundred thirty-nine critically ill adult patients were recruited for this study. Among them, 131 patients (39%) were diagnosed with AKI by the RIFLE criteria and 66 patients were diagnosed as AKI at post-ICU admission (later-onset AKI). Eighty-four AKI patients showed worsening severity during 1 week observation (AKI progression). Although L-FABP, NGAL and IL-18 showed significantly higher area under the curve (AUC)-receiver operating characteristic (ROC) values than semaphorin 3A in detecting established AKI, semaphorin 3A was able to detect later-onset AKI and AKI progression with similar AUC-ROC values compared with the other five biomarkers [AUC-ROC (95% CI) for established AKI 0.64 (0.56-0.71), later-onset AKI 0.71 (0.64-0.78), AKI progression 0.71 (0.64-0.77)]. Urinary semaphorin 3A was not increased in non-progressive established AKI, while the other biomarkers were elevated regardless of further progression. Finally, sepsis did not have any impact on semaphorin 3A while the other urinary biomarkers were increased with sepsis. Semaphorin 3A is a new biomarker of AKI which may have a distinct predictive use for AKI progression when compared with other AKI biomarkers.

Hospital cost analysis of neuromuscular scoliosis surgery.

PubMed

Diefenbach, Christopher; Ialenti, Marc N; Lonner, Baron S; Kamerlink, Jonathan R; Verma, Kushagra; Errico, Thomas J

2013-01-01

A retrospective review of 74 consecutive, surgical patients with neuromuscular scoliosis (NMS). This study evaluates the distribution of hospital and operating room costs incurred during surgical correction of NMS. Recent studies have demonstrated that surgical treatment improves both medical outcomes and the quality of life in patients with progressive NMS. Characterization of the costs incurred at the time of surgery and hospitalization will facilitate the identification of opportunities for cost reduction. Demographic data collected included gender, age, preoperative height, weight, and BMI. Major coronal curvatures and T5-T12 kyphosis were assessed from radiographs. Construct type and number of screws, hooks, and wires implanted were recorded. Surgical costs were calculated based on cost of surgical correction, hospital stay, and postoperative care. Mean age was 15.8 ± 7.3 years; 57% were male. Comorbidities included cerebral palsy (28%) and familial dysautonomia (14%). The mean preoperative major curve magnitude was 60°; minor curve magnitude was 33°. Posterior approach (76%) and pedicle screws (75%) were predominantly utilized. The average length of hospitalization was 8 days (range: 3 to 47). There were six major complications (8%). The total surgical cost was $50,096 ± $23,998. The highest individual cost was for implants ($13,916; 24% of total costs). The second highest was inpatient room and ICU costs ($12,483; 22%); bone grafts were the third ($6,398; 11%). Increased major and minor structural curve, increased total (A/P) levels fused, and increased length of hospital stay predicted an increase in total cost. Major contributors to cost in NMS surgery are implants, inpatient room and ICU costs, and bone grafts. Independent predictors of higher cost are the degree of major and minor structural curve, total number of A/P levels fused, and length of hospital stay. These conclusions provide insight into costs associated with care for a medically fragile and challenging patient population.

Deciphering Periodic Methanol Masers

NASA Astrophysics Data System (ADS)

Stecklum, Bringfried; Caratti o Garatti, Alessio; Henning, Thomas; Hodapp, Klaus; Hopp, Ulrich; Kraus, Alex; Linz, Hendrik; Sanna, Alberto; Sobolev, Andrej; Wolf, Verena

2018-05-01

Impressive progress has been made in recent years on massive star formation, yet the involved high optical depths even at submm/mm wavelengths make it difficult to reveal its details. Recently, accretion bursts of massive YSOs have been identified to cause flares of Class II methanol masers (methanol masers for short) due to enhanced mid-IR pumping. This opens a new window to protostellar accretion variability, and implies that periodic methanol masers hint at cyclic accretion. Pinning down the cause of the periodicity requires joint IR and radio monitoring. We derived the first IR light curve of a periodic maser host from NEOWISE data. The source, G107.298+5.639, is an intermediate-mass YSO hosting methanol and water masers which flare every 34.5 days. Our recent joint K-band and radio observations yielded first but marginal evidence for a phase lag between the rise of IR and maser emission, respectively, and revealed that both NEOWISE and K-band light curves are strongly affected by the light echo from the ambient dust. Both the superior resolution of IRAC over NEOWISE and the longer wavelengths compared to our ground-based imaging are required to inhibit the distractive contamination by the light echo. Thus, we ask for IRAC monitoring of G107 to cover one flare cycle, in tandem with 100-m Effelsberg and 2-m Wendelstein radio and NIR observations to obtain the first high-quality synoptic measurements of this kind of sources. The IR-maser phase lag, the intrinsic shape of the IR light curves and their possible color variation during the cycle allow us to constrain models for the periodic maser excitation. Since methanol masers are signposts of intermediate-mass and massive YSOs, deciphering their variability offers a clue to the dynamics of the accretion-mediated growth of massive stars and their feedback onto the immediate natal environment. The Spitzer light curve of such a maser-hosting YSO would be a legacy science product of the mission.

Construction of a New Growth References for China Based on Urban Chinese Children: Comparison with the WHO Growth Standards

PubMed Central

Zong, Xin-Nan; Li, Hui

2013-01-01

Introduction Growth references for Chinese children should be updated due to the positive secular growth trends and the progress of the smoothing techniques. Human growth differs among the various ethnic groups, so comparison of the China references with the WHO standards helps to understand such differences. Methods The China references, including weight, length/height, head circumference, weight-for-length/height and body mass index (BMI) aged 0–18 years, were constructed based on 69,760 urban infants and preschool children under 7 years and 24,542 urban school children aged 6–20 years derived from two cross-sectional national surveys. The Cole’s LMS method is employed for smoothing the growth curves. Results The merged data sets resulted in a smooth transition at age 6–7 years and continuity of curves from 0 to 18 years. Varying differences were found on the empirical standard deviation (SD) curves in each indicator at nearly all ages between China and WHO. The most noticeable differences occurred in genders, final height and boundary centiles curves. Chinese boys’ weight is strikingly heavier than that of the WHO at age 6–10 years. The height is taller than that of the WHO for boys below 15 years and for girls below 13, but is significantly lower when boys over 15 years and girls over 13. BMI is generally higher than that of the WHO for boys at age 6–16 years but appreciably lower for girls at 3–18 years. Conclusions The differences between China and WHO are mainly caused by the reference populations of different ethnic backgrounds. For practitioners, the choices of the standards/references depend on the population to be assessed and the purpose of the study. The new China references could be applied to facilitate the standardization assessment of growth and nutrition for Chinese children and adolescents in clinical pediatric and public health. PMID:23527219

Is there a correlation between the clinical findings and the radiological findings in chronic maxillary sinus atelectasis?

PubMed

Eyigör, Hülya; Çekiç, Bülent; Turgut Çoban, Deniz; Selçuk, Ömer Tarık; Renda, Levent; Şimşek, Emine Handan; Yılmaz, Mustafa Deniz

2016-07-01

Silent sinus syndrome (SSS) is a clinical syndrome that occurs as a result of chronic maxillary sinus atelectasis (CMA) and is seen with progressive enophthalmos and hypoglobus. The aim of this study was to investigate the correlation between radiological findings and clinical findings in patients with radiologically asymmetrical reduced maxillary sinus volume. A comparison was made of patients with CMA through evaluation of paranasal sinus computed tomography, magnetic resonance imaging examination of maxillary sinus volume of the CMA side and the contralateral side, thickness of the retroantral fat tissue, infraorbital bone curve, uncinate process lateralisation measurement, middle concha diameter, and calculation of the change in location of the inferior rectus muscle. The study included 16 patients. Although a statistically significant difference was determined between the healthy and the pathological sides in respect to maxillary sinus volume, thickness of the retroantral fat tissue, infraorbital bone curve, uncinate process lateralisation measurement, and middle concha diameter (p = 0.00, p = 0.002, p = 0.020, p = 0.020, p = 0.007), no significant difference was determined in respect to the change in location of the inferior rectus muscle (p = 0.154). A positive correlation was determined between the increase in sulcus depth and maxillary sinus volume and inferior orbital bone curve (p < 0.05). In CMA patients suspected of having SSS, radiological maxillary sinus volume analysis, determination of retroantral fat thickness, measurement of the infraorbital bone curve, and measurement of the uncinate process lateralisation can be used as objective tests. However, it should be kept in mind that radiological findings may not always be compatible with the ophthalmological examination findings. Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

[Evaluation of the learning curve of residents in localizing a phantom target with ultrasonography].

PubMed

Dessieux, T; Estebe, J-P; Bloc, S; Mercadal, L; Ecoffey, C

2008-10-01

Few information are available regarding the learning curve in ultrasonography and even less for ultrasound-guided regional anesthesia. This study aimed to evaluate in a training program the learning curve on a phantom of 12 residents novice in ultrasonography. Twelve trainees inexperienced in ultrasonography were given introductory training consisting of didactic formation on the various components of the portable ultrasound machine (i.e. on/off button, gain, depth, resolution, and image storage). Then, students performed three trials, in two sets of increased difficulty, at executing these predefined tasks: adjustments of the machine, then localization of a small plastic piece introduced into roasting pork (3 cm below the surface). At the end of the evaluation, the residents were asked to insert a 22 G needle into an exact predetermined target (i.e. point of fascia intersection). The progression of the needle was continuously controlled by ultrasound visualization using injection of a small volume of water (needle perpendicular to the longitudinal plane of the ultrasound beam). Two groups of two different examiners evaluated for each three trials the skill of the residents (quality, time to perform the machine adjustments, to localize the plastic target, and to hydrolocalize, and volume used for hydrolocalization). After each trial, residents evaluated their performance using a difficulty scale (0: easy to 10: difficult). All residents performed the adjustments from the last trial of each set, with a learning curve observed in terms of duration. Localization of the plastic piece was achieved by all residents at the 6th trial, with a shorter duration of localization. Hydrolocalization was achieved after the 4th trial by all subjects. Difficulty scale was correlated to the number of trials. All these results were independent of the experience of residents in regional anesthesia. Four trials were necessary to adjust correctly the machine, to localize a target, and to complete hydrolocalization. Ultrasonography in regional anesthesia seems to be a fast-learning technique, using this kind of practical training.

Non-linear education gradient across the nutrition transition: mothers’ overweight and the population education transition

PubMed Central

Salinas, Daniel; Baker, David P

2015-01-01

Objective Previous studies found that developed and developing countries present opposite education-overweight gradients but have not considered the dynamics at different levels of national development. A U-inverted curve is hypothesized to best describe the education-overweight association. It is also hypothesized that as the nutrition transition unfolds within nations the shape of education-overweight curve change. Design Multi-level logistic regression estimates the moderating effect of the nutrition transition at the population level on education-overweight gradient. At the individual level, a non-linear estimate of the education association assesses the optimal functional form of the association across the nutrition transition. Setting Twenty-two administrations of the Demographic and Health Survey, collected at different time points across the nutrition transition in nine Latin American/Caribbean countries. Subjects Mothers of reproductive age (15–49) in each administration (n 143,258). Results In the pooled sample, a non-linear education gradient on mothers‘ overweight is found; each additional year of schooling increases the probability of being overweight up to the end of primary schooling, after which each additional year of schooling decreases the probability of overweight. Also, as access to diets of high animal fats and sweeteners increases over time, the curve‘s critical point moves to lower education levels, the detrimental positive effect of education diminishes, and both occur as the overall risk of overweight increases with greater access to harmful diets. Conclusions Both hypotheses are supported. As the nutrition transition progresses, the education-overweight curve steadily shifts to a negative linear association with higher average risk of overweight; and education, at increasingly lower levels, acts as a “social vaccine” against increasing risk of overweight. These empirical patterns fit the general “population education transition” (PET) curve hypothesis about how education influences on health risks are contextualized across population transitions. PMID:26054756

Development and validation of a learning progression for change of seasons, solar and lunar eclipses, and moon phases

NASA Astrophysics Data System (ADS)

Testa, Italo; Galano, Silvia; Leccia, Silvio; Puddu, Emanuella

2015-12-01

In this paper, we report about the development and validation of a learning progression about the Celestial Motion big idea. Existing curricula, research studies on alternative conceptions about these phenomena, and students' answers to an open questionnaire were the starting point to develop initial learning progressions about change of seasons, solar and lunar eclipses, and Moon phases; then, a two-tier multiple choice questionnaire was designed to validate and improve them. The questionnaire was submitted to about 300 secondary students of different school levels (14 to 18 years old). Item response analysis and curve integral method were used to revise the hypothesized learning progressions. Findings support that spatial reasoning is a key cognitive factor for building an explanatory framework for the Celestial Motion big idea, but also suggest that causal reasoning based on physics mechanisms underlying the phenomena, as light flux laws or energy transfers, may significantly impact a students' understanding. As an implication of the study, we propose that the teaching of the three discussed astronomy phenomena should follow a single teaching-learning path along the following sequence: (i) emphasize from the beginning the geometrical aspects of the Sun-Moon-Earth system motion; (ii) clarify consequences of the motion of the Sun-Moon-Earth system, as the changing solar radiation flow on the surface of Earth during the revolution around the Sun; (iii) help students moving between different reference systems (Earth and space observer's perspective) to understand how Earth's rotation and revolution can change the appearance of the Sun and Moon. Instructional and methodological implications are also briefly discussed.

Contemporary patterns of spontaneous labor with normal neonatal outcomes.

PubMed

Zhang, Jun; Landy, Helain J; Branch, D Ware; Burkman, Ronald; Haberman, Shoshana; Gregory, Kimberly D; Hatjis, Christos G; Ramirez, Mildred M; Bailit, Jennifer L; Gonzalez-Quintero, Victor H; Hibbard, Judith U; Hoffman, Matthew K; Kominiarek, Michelle; Learman, Lee A; Van Veldhuisen, Paul; Troendle, James; Reddy, Uma M

2010-12-01

To use contemporary labor data to examine the labor patterns in a large, modern obstetric population in the United States. Data were from the Consortium on Safe Labor, a multicenter retrospective study that abstracted detailed labor and delivery information from electronic medical records in 19 hospitals across the United States. A total of 62,415 parturients were selected who had a singleton term gestation, spontaneous onset of labor, vertex presentation, vaginal delivery, and a normal perinatal outcome. A repeated-measures analysis was used to construct average labor curves by parity. An interval-censored regression was used to estimate duration of labor, stratified by cervical dilation at admission and centimeter by centimeter. Labor may take more than 6 hours to progress from 4 to 5 cm and more than 3 hours to progress from 5 to 6 cm of dilation. Nulliparous and multiparous women appeared to progress at a similar pace before 6 cm. However, after 6 cm, labor accelerated much faster in multiparous than in nulliparous women. The 95 percentiles of the second stage of labor in nulliparous women with and without epidural analgesia were 3.6 and 2.8 hours, respectively. A partogram for nulliparous women is proposed. In a large, contemporary population, the rate of cervical dilation accelerated after 6 cm, and progress from 4 cm to 6 cm was far slower than previously described. Allowing labor to continue for a longer period before 6 cm of cervical dilation may reduce the rate of intrapartum and subsequent repeat cesarean deliveries in the United States.

Noninvasive Computed Tomography–based Risk Stratification of Lung Adenocarcinomas in the National Lung Screening Trial

PubMed Central

Maldonado, Fabien; Duan, Fenghai; Raghunath, Sushravya M.; Rajagopalan, Srinivasan; Karwoski, Ronald A.; Garg, Kavita; Greco, Erin; Nath, Hrudaya; Robb, Richard A.; Bartholmai, Brian J.

2015-01-01

Rationale: Screening for lung cancer using low-dose computed tomography (CT) reduces lung cancer mortality. However, in addition to a high rate of benign nodules, lung cancer screening detects a large number of indolent cancers that generally belong to the adenocarcinoma spectrum. Individualized management of screen-detected adenocarcinomas would be facilitated by noninvasive risk stratification. Objectives: To validate that Computer-Aided Nodule Assessment and Risk Yield (CANARY), a novel image analysis software, successfully risk stratifies screen-detected lung adenocarcinomas based on clinical disease outcomes. Methods: We identified retrospective 294 eligible patients diagnosed with lung adenocarcinoma spectrum lesions in the low-dose CT arm of the National Lung Screening Trial. The last low-dose CT scan before the diagnosis of lung adenocarcinoma was analyzed using CANARY blinded to clinical data. Based on their parametric CANARY signatures, all the lung adenocarcinoma nodules were risk stratified into three groups. CANARY risk groups were compared using survival analysis for progression-free survival. Measurements and Main Results: A total of 294 patients were included in the analysis. Kaplan-Meier analysis of all the 294 adenocarcinoma nodules stratified into the Good, Intermediate, and Poor CANARY risk groups yielded distinct progression-free survival curves (P < 0.0001). This observation was confirmed in the unadjusted and adjusted (age, sex, race, and smoking status) progression-free survival analysis of all stage I cases. Conclusions: CANARY allows the noninvasive risk stratification of lung adenocarcinomas into three groups with distinct post-treatment progression-free survival. Our results suggest that CANARY could ultimately facilitate individualized management of incidentally or screen-detected lung adenocarcinomas. PMID:26052977

Noninvasive Computed Tomography-based Risk Stratification of Lung Adenocarcinomas in the National Lung Screening Trial.

PubMed

Maldonado, Fabien; Duan, Fenghai; Raghunath, Sushravya M; Rajagopalan, Srinivasan; Karwoski, Ronald A; Garg, Kavita; Greco, Erin; Nath, Hrudaya; Robb, Richard A; Bartholmai, Brian J; Peikert, Tobias

2015-09-15

Screening for lung cancer using low-dose computed tomography (CT) reduces lung cancer mortality. However, in addition to a high rate of benign nodules, lung cancer screening detects a large number of indolent cancers that generally belong to the adenocarcinoma spectrum. Individualized management of screen-detected adenocarcinomas would be facilitated by noninvasive risk stratification. To validate that Computer-Aided Nodule Assessment and Risk Yield (CANARY), a novel image analysis software, successfully risk stratifies screen-detected lung adenocarcinomas based on clinical disease outcomes. We identified retrospective 294 eligible patients diagnosed with lung adenocarcinoma spectrum lesions in the low-dose CT arm of the National Lung Screening Trial. The last low-dose CT scan before the diagnosis of lung adenocarcinoma was analyzed using CANARY blinded to clinical data. Based on their parametric CANARY signatures, all the lung adenocarcinoma nodules were risk stratified into three groups. CANARY risk groups were compared using survival analysis for progression-free survival. A total of 294 patients were included in the analysis. Kaplan-Meier analysis of all the 294 adenocarcinoma nodules stratified into the Good, Intermediate, and Poor CANARY risk groups yielded distinct progression-free survival curves (P < 0.0001). This observation was confirmed in the unadjusted and adjusted (age, sex, race, and smoking status) progression-free survival analysis of all stage I cases. CANARY allows the noninvasive risk stratification of lung adenocarcinomas into three groups with distinct post-treatment progression-free survival. Our results suggest that CANARY could ultimately facilitate individualized management of incidentally or screen-detected lung adenocarcinomas.

Identifying the superior measure of rapid fibrosis for predicting premature cirrhosis after liver transplantation for hepatitis C.

PubMed

Howell, J; Sawhney, R; Angus, P; Fink, M; Jones, R; Wang, B Z; Visvanathan, K; Crowley, P; Gow, P

2013-12-01

Hepatitis C virus (HCV) recurrence post liver transplant is universal, with a subgroup of patients developing rapid hepatic fibrosis. Various clinical definitions of rapid fibrosis (RF) have been used to identify risks for rapid progression, but their comparability and efficacy at predicting adverse outcomes has not been determined. Retrospective data analysis was conducted on 100 adult patients with HCV who underwent liver transplantation at a single center. We measured year 1 fibrosis progression (RF defined as METAVIR F score ≥ 1 at 1-year liver biopsy), time to METAVIR F2-stage fibrosis, and fibrosis rate (calculated using liver biopsies graded by METAVIR scoring F0-4; fibrosis rate = fibrosis stage/year post transplant). RF was defined as ≥ 0.5 units/year. Multivariate analysis revealed that donor age and peak HCV viral load were significant risks for RF, when fibrosis rate was used to define RF. Advanced donor age was a risk for rapid progression to F2-stage fibrosis, whereas genotype 2 or 3 HCV infection was protective. Fibrosis rate had the strongest correlation with time to cirrhosis development (P < 0.0001, r = -0.76) and was the most accurate predictor of rapid graft cirrhosis (P < 0.0001, area under the curve 0.979, sensitivity 100%, specificity 94%). Different measures of RF progression identify different risks for RF and are not directly comparable. Fibrosis rate was the most accurate predictor of rapid graft cirrhosis. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Contemporary Patterns of Spontaneous Labor With Normal Neonatal Outcomes

PubMed Central

Zhang, Jun; Landy, Helain J.; Branch, D. Ware; Burkman, Ronald; Haberman, Shoshana; Gregory, Kimberly D.; Hatjis, Christos G.; Ramirez, Mildred M.; Bailit, Jennifer L.; Gonzalez-Quintero, Victor H.; Hibbard, Judith U.; Hoffman, Matthew K.; Kominiarek, Michelle; Learman, Lee A.; Van Veldhuisen, Paul; Troendle, James; Reddy, Uma M.

2013-01-01

Objective To use contemporary labor data to examine the labor patterns in a large, modern obstetric population in the United States. Methods Data were from the Consortium on Safe Labor, a multicenter retrospective study that abstracted detailed labor and delivery information from electronic medical records in 19 hospitals across the United States. A total of 62,415 parturients were selected who had a singleton term gestation, spontaneous onset of labor, vertex presentation, vaginal delivery, and a normal perinatal outcome. A repeated-measures analysis was used to construct average labor curves by parity. An interval-censored regression was used to estimate duration of labor stratified by cervical dilation at admission and centimeter by centimeter. Results Labor may take over 6 hours to progress from 4 to 5 cm and over 3 hours to progress from 5 to 6 cm of dilation. Nulliparas and multiparas appeared to progress at a similar pace before 6 cm. However, after 6 cm labor accelerated much faster in multiparas than in nulliparas. The 95th percentile of the 2nd stage of labor in nulliparas with and without epidural analgesia was 3.6 and 2.8 hours, respectively. A partogram for nulliparas is proposed. Conclusion In a large, contemporary population, the rate of cervical dilation accelerated after 6 cm and progress from 4 to 6 cm was far slower than previously described. Allowing labor to continue for a longer period before 6 cm of cervical dilation may reduce the rate of intrapartum and subsequent repeat cesarean deliveries in the United States. PMID:21099592

Complexity and Anisotropy of Plastic Flow of α-Ti Probed by Acoustic Emission and Local Extensometry.

PubMed

Lebyodkin, Mikhail; Amouzou, Kékéli; Lebedkina, Tatiana; Richeton, Thiebaud; Roth, Amandine

2018-06-22

Current progress in the prediction of mechanical behavior of solids requires understanding of spatiotemporal complexity of plastic flow caused by self-organization of crystal defects. It may be particularly important in hexagonal materials because of their strong anisotropy and combination of different mechanisms of plasticity, such as dislocation glide and twinning. These materials often display complex behavior even on the macroscopic scale of deformation curves, e.g., a peculiar three-stage elastoplastic transition, the origin of which is a matter of debates. The present work is devoted to a multiscale study of plastic flow in α-Ti, based on simultaneous recording of deformation curves, 1D local strain field, and acoustic emission (AE). It is found that the average AE activity also reveals three-stage behavior, but in a qualitatively different way depending on the crystallographic orientation of the sample axis. On the finer scale, the statistical analysis of AE events and local strain rates testifies to an avalanche-like character of dislocation processes, reflected in power-law probability distribution functions. The results are discussed from the viewpoint of collective dislocation dynamics and are confronted to predictions of a recent micromechanical model of Ti strain hardening.

Calculating Potential Energy Curves with Quantum Monte Carlo

NASA Astrophysics Data System (ADS)

Powell, Andrew D.; Dawes, Richard

2014-06-01

Quantum Monte Carlo (QMC) is a computational technique that can be applied to the electronic Schrödinger equation for molecules. QMC methods such as Variational Monte Carlo (VMC) and Diffusion Monte Carlo (DMC) have demonstrated the capability of capturing large fractions of the correlation energy, thus suggesting their possible use for high-accuracy quantum chemistry calculations. QMC methods scale particularly well with respect to parallelization making them an attractive consideration in anticipation of next-generation computing architectures which will involve massive parallelization with millions of cores. Due to the statistical nature of the approach, in contrast to standard quantum chemistry methods, uncertainties (error-bars) are associated with each calculated energy. This study focuses on the cost, feasibility and practical application of calculating potential energy curves for small molecules with QMC methods. Trial wave functions were constructed with the multi-configurational self-consistent field (MCSCF) method from GAMESS-US.[1] The CASINO Monte Carlo quantum chemistry package [2] was used for all of the DMC calculations. An overview of our progress in this direction will be given. References: M. W. Schmidt et al. J. Comput. Chem. 14, 1347 (1993). R. J. Needs et al. J. Phys.: Condensed Matter 22, 023201 (2010).

The expression ratio of Map7/B2M is prognostic for survival in patients with stage II colon cancer.

PubMed

Blum, Craig; Graham, Amanda; Yousefzadeh, Matt; Shrout, Jessica; Benjamin, Katie; Krishna, Murli; Hoda, Raza; Hoda, Rana; Cole, David J; Garrett-Mayer, Elizabeth; Reed, Carolyn; Wallace, Michael; Mitas, Michael

2008-09-01

Colorectal cancer (CRC) is the second most frequent cause of cancer-related death in the United States. To determine whether certain molecular markers might be prognostic for survival, we measured by quantitative real-time RT-PCR the expression levels of 15 previously studied genes that are known to be up-regulated or down-regulated in the progression of epithelial cancers. The tumor samples were extracted from formalin-fixed paraffin-embedded primary tissues derived from patients with Stage II CRC who developed disease recurrence within two years (n=10), or were disease-free for at least 4 years (n=12). We were able to determine, by AUC curve analysis, that the ratio of microtubule associated protein 7 (Map7)/B2M was predictive of outcome in our sample set. Further, using Kaplan-Meier survival analysis, we observed significantly different curves as a function of marker positivity for the Map7/B2M (p=0.0001; HR=11) expression ratio. This suggests that the expression ratio of Map7/B2M may serve as a valuable prognostic marker in patients with Stage II colon cancer, and potentially guide therapeutic decision making.

The expression ratio of Map7/B2M is prognostic for survival in patients with stage II colon cancer

PubMed Central

BLUM, CRAIG; GRAHAM, AMANDA; YOUSEFZADEH, MATT; SHROUT, JESSICA; BENJAMIN, KATIE; KRISHNA, MURLI; HODA, RAZA; HODA, RANA; COLE, DAVID J.; GARRETT-MAYER, ELIZABETH; REED, CAROLYN; WALLACE, MICHAEL; MITAS, MICHAEL

2012-01-01

Colorectal cancer (CRC) is the second most frequent cause of cancer-related death in the United States. To determine whether certain molecular markers might be prognostic for survival, we measured by quantitative real-time RT-PCR the expression levels of 15 previously studied genes that are known to be up-regulated or down-regulated in the progression of epithelial cancers. The tumor samples were extracted from formalin-fixed paraffin-embedded primary tissues derived from patients with Stage II CRC who developed disease recurrence within two years (n=10), or were disease-free for at least 4 years (n=12). We were able to determine, by AUC curve analysis, that the ratio of microtubule associated protein 7 (Map7)/B2M was predictive of outcome in our sample set. Further, using Kaplan-Meier survival analysis, we observed significantly different curves as a function of marker positivity for the Map7/B2M (p=0.0001; HR=11) expression ratio. This suggests that the expression ratio of Map7/B2M may serve as a valuable prognostic marker in patients with Stage II colon cancer, and potentially guide therapeutic decision making. PMID:18695889

Towards a comprehensive barcode library for arctic life - Ephemeroptera, Plecoptera, and Trichoptera of Churchill, Manitoba, Canada

PubMed Central

2009-01-01

Background This study reports progress in assembling a DNA barcode reference library for Ephemeroptera, Plecoptera, and Trichoptera ("EPTs") from a Canadian subarctic site, which is the focus of a comprehensive biodiversity inventory using DNA barcoding. These three groups of aquatic insects exhibit a moderate level of species diversity, making them ideal for testing the feasibility of DNA barcoding for routine biotic surveys. We explore the correlation between the morphological species delineations, DNA barcode-based haplotype clusters delimited by a sequence threshold (2%), and a threshold-free approach to biodiversity quantification--phylogenetic diversity. Results A DNA barcode reference library is built for 112 EPT species for the focal region, consisting of 2277 COI sequences. Close correspondence was found between EPT morphospecies and haplotype clusters as designated using a standard threshold value. Similarly, the shapes of taxon accumulation curves based upon haplotype clusters were very similar to those generated using phylogenetic diversity accumulation curves, but were much more computationally efficient. Conclusion The results of this study will facilitate other lines of research on northern EPTs and also bode well for rapidly conducting initial biodiversity assessments in unknown EPT faunas. PMID:20003245

Effect of fenbendazole on an autoimmune mouse model.

PubMed

Cray, Carolyn; Watson, Toshiba; Zaias, Julia; Altman, Norman H

2013-01-01

Fenbendazole is an anthelmintic drug widely used to treat and prevent pinworm infection in laboratory rodents. Data regarding possible side effects of fenbendazole on the immune system are conflicting, potentially due to the design of treatment protocols. The purpose of the current study was to determine the effects of 2 fenbendazole therapeutic regimens (continuous for 5 wk and alternating weeks [that is, 1 wk on, 1 wk off] for 9 wk) on the development of autoimmune disease in (NZB × NZW)F1 mice. No significant differences in survival curves or weight were observed between the treatment groups and cohort mice receiving nonmedicated feed. At the termination of the experiment, there were no differences in tissue pathology. Hematocrit decreased and BUN increased over time in all groups, but no significant differences were present between groups. After the cessation of treatment, mice fed the medicated diet continuously for 5 wk showed an increase in antiDNA antibody. Although this difference was significant, it did not affect survival curves or disease-related tissue or blood changes. These data indicate that common protocols of fenbendazole treatment do not alter the progression of autoimmune disease in (NZB × NZW)F1 mice.

Effect of Fenbendazole on an Autoimmune Mouse Model

PubMed Central

Cray, Carolyn; Watson, Toshiba; Zaias, Julia; Altman, Norman H

2013-01-01

Fenbendazole is an anthelmintic drug widely used to treat and prevent pinworm infection in laboratory rodents. Data regarding possible side effects of fenbendazole on the immune system are conflicting, potentially due to the design of treatment protocols. The purpose of the current study was to determine the effects of 2 fenbendazole therapeutic regimens (continuous for 5 wk and alternating weeks [that is, 1 wk on, 1 wk off] for 9 wk) on the development of autoimmune disease in (NZB × NZW)F1 mice. No significant differences in survival curves or weight were observed between the treatment groups and cohort mice receiving nonmedicated feed. At the termination of the experiment, there were no differences in tissue pathology. Hematocrit decreased and BUN increased over time in all groups, but no significant differences were present between groups. After the cessation of treatment, mice fed the medicated diet continuously for 5 wk showed an increase in antiDNA antibody. Although this difference was significant, it did not affect survival curves or disease-related tissue or blood changes. These data indicate that common protocols of fenbendazole treatment do not alter the progression of autoimmune disease in (NZB × NZW)F1 mice. PMID:23849411

First order augmentation to tensor voting for boundary inference and multiscale analysis in 3D.

PubMed

Tong, Wai-Shun; Tang, Chi-Keung; Mordohai, Philippos; Medioni, Gérard

2004-05-01

Most computer vision applications require the reliable detection of boundaries. In the presence of outliers, missing data, orientation discontinuities, and occlusion, this problem is particularly challenging. We propose to address it by complementing the tensor voting framework, which was limited to second order properties, with first order representation and voting. First order voting fields and a mechanism to vote for 3D surface and volume boundaries and curve endpoints in 3D are defined. Boundary inference is also useful for a second difficult problem in grouping, namely, automatic scale selection. We propose an algorithm that automatically infers the smallest scale that can preserve the finest details. Our algorithm then proceeds with progressively larger scales to ensure continuity where it has not been achieved. Therefore, the proposed approach does not oversmooth features or delay the handling of boundaries and discontinuities until model misfit occurs. The interaction of smooth features, boundaries, and outliers is accommodated by the unified representation, making possible the perceptual organization of data in curves, surfaces, volumes, and their boundaries simultaneously. We present results on a variety of data sets to show the efficacy of the improved formalism.

Physiotherapeutic scoliosis-specific exercises for adolescents with idiopathic scoliosis.

PubMed

Bettany-Saltikov, J; Parent, E; Romano, M; Villagrasa, M; Negrini, S

2014-02-01

The use of exercises for the treatment of Adolescents with Idiopathic Scoliosis is controversial. Whilst exercises are routinely used in a number of central and southern European countries, most centres in the rest of the world (mainly in Anglo-Saxon countries), do not advocate its use. One of the reasons for this is that many health care professionals are usually not conversant with the differences between generalised physiotherapy exercises and physiotherapeutic scoliosis-specific exercises (PSSE): while the former are generic exercises usually consisting of low-impact stretching and strengthening activities like yoga, Pilates and the Alexander technique, PSSE consist of a program of curve-specific exercise protocols which are individually adapted to a patients' curve site, magnitude and clinical characteristics. PSSEs are performed with the therapeutic aim of reducing the deformity and preventing its progression. It also aims to stabilise the improvements achieved with the ultimate goal of limiting the need for corrective braces or the necessity of surgery. This paper introduces the different 'Schools' and approaches of PSSE currently practiced (Scientific Exercise Approach to Scoliosis - SEAS, Schroth, Barcelona Scoliosis Physical Therapy School - BSPTS, Dobomed, Side Shift, Functional Individual Therapy of Scoliosis - FITS and Lyon) and discusses their commonalities and differences.

Prognostic value of inflammation-based scores in patients with osteosarcoma

PubMed Central

Liu, Bangjian; Huang, Yujing; Sun, Yuanjue; Zhang, Jianjun; Yao, Yang; Shen, Zan; Xiang, Dongxi; He, Aina

2016-01-01

Systemic inflammation responses have been associated with cancer development and progression. C-reactive protein (CRP), Glasgow prognostic score (GPS), neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), lymphocyte-monocyte ratio (LMR), and neutrophil-platelet score (NPS) have been shown to be independent risk factors in various types of malignant tumors. This retrospective analysis of 162 osteosarcoma cases was performed to estimate their predictive value of survival in osteosarcoma. All statistical analyses were performed by SPSS statistical software. Receiver operating characteristic (ROC) analysis was generated to set optimal thresholds; area under the curve (AUC) was used to show the discriminatory abilities of inflammation-based scores; Kaplan-Meier analysis was performed to plot the survival curve; cox regression models were employed to determine the independent prognostic factors. The optimal cut-off points of NLR, PLR, and LMR were 2.57, 123.5 and 4.73, respectively. GPS and NLR had a markedly larger AUC than CRP, PLR and LMR. High levels of CRP, GPS, NLR, PLR, and low level of LMR were significantly associated with adverse prognosis (P < 0.05). Multivariate Cox regression analyses revealed that GPS, NLR, and occurrence of metastasis were top risk factors associated with death of osteosarcoma patients. PMID:28008988

Fuzzy set methods for object recognition in space applications

NASA Technical Reports Server (NTRS)

Keller, James M.

1991-01-01

Progress on the following tasks is reported: (1) fuzzy set-based decision making methodologies; (2) feature calculation; (3) clustering for curve and surface fitting; and (4) acquisition of images. The general structure for networks based on fuzzy set connectives which are being used for information fusion and decision making in space applications is described. The structure and training techniques for such networks consisting of generalized means and gamma-operators are described. The use of other hybrid operators in multicriteria decision making is currently being examined. Numerous classical features on image regions such as gray level statistics, edge and curve primitives, texture measures from cooccurrance matrix, and size and shape parameters were implemented. Several fractal geometric features which may have a considerable impact on characterizing cluttered background, such as clouds, dense star patterns, or some planetary surfaces, were used. A new approach to a fuzzy C-shell algorithm is addressed. NASA personnel are in the process of acquiring suitable simulation data and hopefully videotaped actual shuttle imagery. Photographs have been digitized to use in the algorithms. Also, a model of the shuttle was assembled and a mechanism to orient this model in 3-D to digitize for experiments on pose estimation is being constructed.

The Effects of Aperiodic Perturbation on the Last Good Surface of a Single-Null Divertor Tokamak

NASA Astrophysics Data System (ADS)

Jordan, Joseph; Punjabi, Alkesh; Ali, Halima

2003-10-01

An area-preserving discrete mapping, called the Simple Map is used to analyze the effects of aperiodic perturbation on the last good magnetic surface of a single-null divertor tokamak. The SM was developed by Punjabi and Boozer /1/. The SM equations are modified to reflect the effect of aperiodic perturbation: Xn + 1 = Xn - (k+δ_aperiodics(n))Y_n(1-Y_n), Y_n+1 = Yn + kX_n+1 where δ_aperiodic is the amplitude of the aperiodic perturbation. The equations are coded into FORTRAN and used in conjunction with a graphing program to show the trajectories for different amplitudes of aperiodic perturbation. As the aperiodic perturbation is increased, the trajectories break from a clean curve and develop strange behavior as they approach chaos. The progression of the trajectories from a clean curve to a chaotic one is observed, and the results are presented in this paper. This project is supported by NASA SHARP and US DOE Grant Number DE-F02-02ER54673. The research was done under the mentorship of Profs. Punjabi and Ali. 1. Punjabi A., Verma A., and Boozer A., Phys. Rev. Lett, 69, 3322 (1992)

An Accurately Controlled Antagonistic Shape Memory Alloy Actuator with Self-Sensing

PubMed Central

Wang, Tian-Miao; Shi, Zhen-Yun; Liu, Da; Ma, Chen; Zhang, Zhen-Hua

2012-01-01

With the progress of miniaturization, shape memory alloy (SMA) actuators exhibit high energy density, self-sensing ability and ease of fabrication, which make them well suited for practical applications. This paper presents a self-sensing controlled actuator drive that was designed using antagonistic pairs of SMA wires. Under a certain pre-strain and duty cycle, the stress between two wires becomes constant. Meanwhile, the strain to resistance curve can minimize the hysteresis gap between the heating and the cooling paths. The curves of both wires are then modeled by fitting polynomials such that the measured resistance can be used directly to determine the difference between the testing values and the target strain. The hysteresis model of strains to duty cycle difference has been used as compensation. Accurate control is demonstrated through step response and sinusoidal tracking. The experimental results show that, under a combination control program, the root-mean-square error can be reduced to 1.093%. The limited bandwidth of the frequency is estimated to be 0.15 Hz. Two sets of instruments with three degrees of freedom are illustrated to show how this type actuator could be potentially implemented. PMID:22969368

[Learning curve of vacuum extraction in residency: a preliminary study].

PubMed

Velemir, L; Vendittelli, F; Bonnefoy, C; Accoceberry, M; Savary, D; Gallot, D

2009-09-01

The aim of this study was to assess the lurning curve of young residents for vacuum extraction. All vacuum extractions performed in our department by five residents (< or =5th semester) during a study period of nine months were systematically supervised by a senior who fulfilled an assessment questionnaire from which was calculated a score reflecting the quality of the extraction. Fifty-four vacuum extractions were assessed with a mean of 10.8+/-2.9 (range, 10-13) procedures by resident. We compared the group including the six first procedures performed by each resident (group 1, n = 30) with the group including the following procedures (group 2, n = 24). We observed in the group 2 compared to the group 1, a significant improvement of the scores mean (12.3+/-5.4 vs 8.4+/-6.2, p = 0.016) and a significant reduction of the need for manual assistance by the senior (12.5% vs 40%, p = 0.034). We report a method for the learning and assessment of vacuum extraction feasible at "the bed" of the patient. This approach allows to observe a significant progression of the resident for the technique of vacuum extraction on a dozen of procedures.

Tendency for interlaboratory precision in the GMO analysis method based on real-time PCR.

PubMed

Kodama, Takashi; Kurosawa, Yasunori; Kitta, Kazumi; Naito, Shigehiro

2010-01-01

The Horwitz curve estimates interlaboratory precision as a function only of concentration, and is frequently used as a method performance criterion in food analysis with chemical methods. The quantitative biochemical methods based on real-time PCR require an analogous criterion to progressively promote method validation. We analyzed the tendency of precision using a simplex real-time PCR technique in 53 collaborative studies of seven genetically modified (GM) crops. Reproducibility standard deviation (SR) and repeatability standard deviation (Sr) of the genetically modified organism (GMO) amount (%) was more or less independent of GM crops (i.e., maize, soybean, cotton, oilseed rape, potato, sugar beet, and rice) and evaluation procedure steps. Some studies evaluated whole steps consisting of DNA extraction and PCR quantitation, whereas others focused only on the PCR quantitation step by using DNA extraction solutions. Therefore, SR and Sr for GMO amount (%) are functions only of concentration similar to the Horwitz curve. We proposed S(R) = 0.1971C 0.8685 and S(r) = 0.1478C 0.8424, where C is the GMO amount (%). We also proposed a method performance index in GMO quantitative methods that is analogous to the Horwitz Ratio.

Numerical investigation of power consumption and mixing time in a stirred vessel with regular and multiscale impellers

NASA Astrophysics Data System (ADS)

Basbug, Salur; Papadakis, George; Vassilicos, Christos

2015-11-01

The flow field inside a stirred tank is obtained by means of direct numerical simulation based on finite volume method at Re =500. Two different types of four-bladed radial impellers are considered: the first one is a regular type with rectangular blades and the second one is a modified version of the former with irregular blade edges, having the same thickness and the surface area. The shaft power is averaged over more than sixty revolutions and the comparison between the two cases shows that the impeller with irregular blades has lower energy consumption. Moreover, a passive scalar is injected into the vessel for a quarter period of revolution and the scalar transport equation is solved to investigate the mixing times. The coefficient of variation of the passive scalar is averaged over the whole volume in order to obtain a quantitative indicator of the mixing progress. The homogenization curves depend on the instantaneous flow conditions due to the transient nature of the mixing process, therefore multiple curves are averaged to obtain a representative result. There are indications that irregular blades can decrease mixing time with respect to regular ones.

Thermotolerance in preirradiated intestine and its influence on time-temperature relationships

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

Hume, S.P.; Marigold, J.C.; Manjil, L.G.

The crypt compartment of mouse jejunum showed a transient increase in thermal susceptibility approximately 10 days after moderate X-ray doses to the abdomen (9-10 Gy). The increase in response was manifest as an increase in slope of the crypt dose-response curve but was limited to temperatures below 43/sup 0/C. As a result, the 43/sup 0/C inflexion in the Arrhenius plot (the relationship between treatment time and temperature) for thermal sensitivity of crypts was eliminated in preirradiated tissue, and the curve became monophasic over the range 42.0-44.5/sup 0/C. At temperatures below 42/sup 0/C, the curve again deviated. At supranormal temperatures ofmore » 42/sup 0/C and below, the durations of hyperthermia needed for measurable effect were sufficient to allow thermotolerance to be expressed within the heating period. Neither the threshold heating times nor this thermotolerance were affected by prior irradiation. In the temperature range 42-43/sup 0/C, an earlier development of thermotolerance could be demonstrated in control tissue by challenging with an acute high-temperature heat treatment. This thermotolerance was eliminated in preirradiated tissue, resulting in the apparent increase in sensitivity. The findings support the view that the complex nature of the time-temperature relationship seen in normal tissue in vivo is a manifestation of the ability of the tissue to progressively acquire a thermotolerant state during treatment at temperatures below approximately 43/sup 0/C, so that the intrinsic sensitivity is modulated while being assessed.« less

Converging or Crossing Curves: Untie the Gordian Knot or Cut it? Appropriate Statistics for Non-Proportional Hazards in Decitabine DACO-016 Study (AML).

PubMed

Tomeczkowski, Jörg; Lange, Ansgar; Güntert, Andreas; Thilakarathne, Pushpike; Diels, Joris; Xiu, Liang; De Porre, Peter; Tapprich, Christoph

2015-09-01

Among patients with acute myeloid leukemia (AML), the DACO-016 randomized study showed reduction in mortality for decitabine [Dacogen(®) (DAC), Eisai Inc., Woodcliff Lake, NJ, USA] compared with treatment choice (TC): at primary analysis the hazard ratio (HR) was 0.85 (95% confidence interval 0.69-1.04; stratified log-rank P = 0.108). With two interim analyses, two-sided alpha was adjusted to 0.0462. With 1-year additional follow-up the HR reached 0.82 (nominal P = 0.0373). These data resulted in approval of DAC in the European Union, though not in the United States. Though pre-specified, the log-rank test could be considered not optimal to assess the observed survival difference because of the non-proportional hazard nature of the survival curves. We applied the Wilcoxon test as a sensitivity analysis. Patients were randomized to DAC (N = 242) or TC (N = 243). One-hundred and eight (44.4%) patients in the TC arm and 91 (37.6%) patients in the DAC arm selectively crossed over to subsequent disease modifying therapies at progression, which might impact the survival beyond the median with resultant converging curves (and disproportional hazards). The stratified Wilcoxon test showed a significant improvement in median (CI 95%) overall survival with DAC [7.7 (6.2; 9.2) months] versus TC [5.0 (4.3; 6.3) months; P = 0.0458]. Wilcoxon test indicated significant increase in survival for DAC versus TC compared to log-rank test. Janssen-Cilag GmbH.

The Oxford unicompartmental knee fails at a high rate in a high-volume knee practice.

PubMed

Schroer, William C; Barnes, C Lowry; Diesfeld, Paul; LeMarr, Angela; Ingrassia, Rachel; Morton, Diane J; Reedy, Mary

2013-11-01

The Oxford knee is a unicompartmental implant featuring a mobile-bearing polyethylene component with excellent long-term survivorship results reported by the implant developers and early adopters. By contrast, other studies have reported higher revision rates in large academic practices and in national registries. Registry data have shown increased failure with this implant especially by lower-volume surgeons and institutions. In the setting of a high-volume knee arthroplasty practice, we sought to determine (1) the failure rate of the Oxford unicompartmental knee implant using a failure definition for aseptic loosening that combined clinical features, plain radiographs, and scintigraphy, and (2) whether increased experience with this implant would decrease failure rate, if there is a learning curve effect. Eighty-three Oxford knee prostheses were implanted between September 2005 and July 2008 by the principal investigator. Radiographic and clinical data were available for review for all cases. A failed knee was defined as having recurrent pain after an earlier period of recovery from surgery, progressive radiolucent lines compared with initial postoperative radiographs, and a bone scan showing an isolated area of uptake limited to the area of the replaced compartment. Eleven knees in this series failed (13%); Kaplan-Meier survivorship was 86.5% (95% CI, 78.0%-95.0%) at 5 years. Failure occurrences were distributed evenly over the course of the study period. No learning curve effect was identified. Based on these findings, including a high failure rate of the Oxford knee implant and the absence of any discernible learning curve effect, the principal investigator no longer uses this implant.

Congenital scoliosis - presentation of three severe cases treated conservatively.

PubMed

Weiss, H-R

2008-01-01

In view of the very limited data about conservative treatment of patients with congenital scoliosis (CS) available, early surgery is suggested already in mild cases with formation failures in the first three years of life. It is common sense that patients with failures of segmentation will not benefit from conservative treatment at all and the same applies to failures of formation with curves of >50 degrees in infancy. Two patients with rib synostosis denied surgery before entering the pubertal growth spurt. These patients have been treated conservatively with braces and Scoliosis In-Patient Rehabilitation (SIR) and now are beyond the pubertal growth spurt. One patient with a formation failure and a curve of >50 degrees lumbar has been treated with the help of braces and physiotherapy from 1.6 years on and is still under treatment now at the age of 15 years. Severe decompensation was prevented in the two patients with failure of segmentation, however a severe thoracic deformity is evident with underdeveloped lung function and severe restrictive ventilation disorder. The patient with failure of formation is well developed, now without cosmetic or physical complaints although his curve progressed at the end of the growth spurt due to final mal-compliance. Failures of segmentation should be advised to have surgery before entering the pubertal growth spurt. In case they deny, conservative treatment can at least in part be beneficial. For patients with failures of formation conservative treatment should be suggested in the first place because long-term outcomes of early surgery beyond pubertal growth spurt are not yet revealed.

Cross-country transferability of multi-variable damage models

NASA Astrophysics Data System (ADS)

Wagenaar, Dennis; Lüdtke, Stefan; Kreibich, Heidi; Bouwer, Laurens

2017-04-01

Flood damage assessment is often done with simple damage curves based only on flood water depth. Additionally, damage models are often transferred in space and time, e.g. from region to region or from one flood event to another. Validation has shown that depth-damage curve estimates are associated with high uncertainties, particularly when applied in regions outside the area where the data for curve development was collected. Recently, progress has been made with multi-variable damage models created with data-mining techniques, i.e. Bayesian Networks and random forest. However, it is still unknown to what extent and under which conditions model transfers are possible and reliable. Model validations in different countries will provide valuable insights into the transferability of multi-variable damage models. In this study we compare multi-variable models developed on basis of flood damage datasets from Germany as well as from The Netherlands. Data from several German floods was collected using computer aided telephone interviews. Data from the 1993 Meuse flood in the Netherlands is available, based on compensations paid by the government. The Bayesian network and random forest based models are applied and validated in both countries on basis of the individual datasets. A major challenge was the harmonization of the variables between both datasets due to factors like differences in variable definitions, and regional and temporal differences in flood hazard and exposure characteristics. Results of model validations and comparisons in both countries are discussed, particularly in respect to encountered challenges and possible solutions for an improvement of model transferability.

Safety, efficiency and learning curves in robotic surgery: a human factors analysis.

PubMed

Catchpole, Ken; Perkins, Colby; Bresee, Catherine; Solnik, M Jonathon; Sherman, Benjamin; Fritch, John; Gross, Bruno; Jagannathan, Samantha; Hakami-Majd, Niv; Avenido, Raymund; Anger, Jennifer T

2016-09-01

Expense, efficiency of use, learning curves, workflow integration and an increased prevalence of serious incidents can all be barriers to adoption. We explored an observational approach and initial diagnostics to enhance total system performance in robotic surgery. Eighty-nine robotic surgical cases were observed in multiple operating rooms using two different surgical robots (the S and Si), across several specialties (Urology, Gynecology, and Cardiac Surgery). The main measures were operative duration and rate of flow disruptions-described as 'deviations from the natural progression of an operation thereby potentially compromising safety or efficiency.' Contextual parameters collected were surgeon experience level and training, type of surgery, the model of robot and patient factors. Observations were conducted across four operative phases (operating room pre-incision; robot docking; main surgical intervention; post-console). A mean of 9.62 flow disruptions per hour (95 % CI 8.78-10.46) were predominantly caused by coordination, communication, equipment and training problems. Operative duration and flow disruption rate varied with surgeon experience (p = 0.039; p < 0.001, respectively), training cases (p = 0.012; p = 0.007) and surgical type (both p < 0.001). Flow disruption rates in some phases were also sensitive to the robot model and patient characteristics. Flow disruption rate is sensitive to system context and generates improvement diagnostics. Complex surgical robotic equipment increases opportunities for technological failures, increases communication requirements for the whole team, and can reduce the ability to maintain vision in the operative field. These data suggest specific opportunities to reduce the training costs and the learning curve.

Global geometric torsion estimation in adolescent idiopathic scoliosis.

PubMed

Kadoury, Samuel; Shen, Jesse; Parent, Stefan

2014-04-01

Several attempts have been made to measure geometrical torsion in adolescent idiopathic scoliosis (AIS) and quantify the three-dimensional (3D) deformation of the spine. However, these approaches are sensitive to imprecisions in the 3D modeling of the anatomy and can only capture the effect locally at the vertebrae, ignoring the global effect at the regional level and thus have never been widely used to follow the progression of a deformity. The goal of this work was to evaluate the relevance of a novel geometric torsion descriptor based on a parametric modeling of the spinal curve as a 3D index of scoliosis. First, an image-based approach anchored on prior statistical distributions is used to reconstruct the spine in 3D from biplanar X-rays. Geometric torsion measuring the twisting effect of the spine is then estimated using a technique that approximates local arc-lengths with parametric curve fitting centered at the neutral vertebra in different spinal regions. We first evaluated the method with simulated experiments, demonstrating the method's robustness toward added noise and reconstruction inaccuracies. A pilot study involving 65 scoliotic patients exhibiting different types of deformities was also conducted. Results show the method is able to discriminate between different types of deformation based on this novel 3D index evaluated in the main thoracic and thoracolumbar/lumbar regions. This demonstrates that geometric torsion modeled by parametric spinal curve fitting is a robust tool that can be used to quantify the 3D deformation of AIS and possibly exploited as an index to classify the 3D shape.

Zooxanthellae harvested by ciliates associated with brown band syndrome of corals remain photosynthetically competent.

PubMed

Ulstrup, Karin E; Kühl, Michael; Bourne, David G

2007-03-01

Brown band syndrome is a new coral affliction characterized by a local accumulation of yet-unidentified ciliates migrating as a band along the branches of coral colonies. In the current study, morphologically intact zooxanthellae (= Symbiodinium) were observed in great numbers inside the ciliates (>50 dinoflagellates per ciliate). Microscale oxygen measurements and variable chlorophyll a fluorescence analysis along with microscopic observations demonstrated that zooxanthellae within the ciliates are photosynthetically competent and do not become compromised during the progression of the brown band zone. Zooxanthellae showed similar trends in light acclimation in a comparison of rapid light curve and steady-state light curve measures of variable chlorophyll a fluorescence. Extended light exposure of steady-state light curves resulted in higher quantum yields of photosystem II. The brown band tissue exhibited higher photosynthetically active radiation absorptivity, indicating more efficient light absorption due to a higher density of zooxanthellae in the ciliate-dominated zone. This caused relatively higher gross photosynthesis rates in the zone with zooxanthella-containing ciliates compared to healthy coral tissue. The observation of photosynthetically active intracellular zooxanthellae in the ciliates suggests that the latter can benefit from photosynthates produced by ingested zooxanthellae and from photosynthetic oxygen production that alleviates diffusion limitation of oxic respiration in the densely populated brown band tissue. It remains to be shown whether the zooxanthellae form a stable symbiotic association with the ciliate or are engulfed incidentally during grazing on coral tissue and then maintained as active inside the ciliate for a period before being digested and replaced by new zooxanthellae.

Zooxanthellae Harvested by Ciliates Associated with Brown Band Syndrome of Corals Remain Photosynthetically Competent▿

PubMed Central

Ulstrup, Karin E.; Kühl, Michael; Bourne, David G.

2007-01-01

Brown band syndrome is a new coral affliction characterized by a local accumulation of yet-unidentified ciliates migrating as a band along the branches of coral colonies. In the current study, morphologically intact zooxanthellae (= Symbiodinium) were observed in great numbers inside the ciliates (>50 dinoflagellates per ciliate). Microscale oxygen measurements and variable chlorophyll a fluorescence analysis along with microscopic observations demonstrated that zooxanthellae within the ciliates are photosynthetically competent and do not become compromised during the progression of the brown band zone. Zooxanthellae showed similar trends in light acclimation in a comparison of rapid light curve and steady-state light curve measures of variable chlorophyll a fluorescence. Extended light exposure of steady-state light curves resulted in higher quantum yields of photosystem II. The brown band tissue exhibited higher photosynthetically active radiation absorptivity, indicating more efficient light absorption due to a higher density of zooxanthellae in the ciliate-dominated zone. This caused relatively higher gross photosynthesis rates in the zone with zooxanthella-containing ciliates compared to healthy coral tissue. The observation of photosynthetically active intracellular zooxanthellae in the ciliates suggests that the latter can benefit from photosynthates produced by ingested zooxanthellae and from photosynthetic oxygen production that alleviates diffusion limitation of oxic respiration in the densely populated brown band tissue. It remains to be shown whether the zooxanthellae form a stable symbiotic association with the ciliate or are engulfed incidentally during grazing on coral tissue and then maintained as active inside the ciliate for a period before being digested and replaced by new zooxanthellae. PMID:17259357

The Benslimane's Artistic Model for Leg Beauty.

PubMed

Benslimane, Fahd

2012-08-01

In 2000, the author started observing legs considered to be attractive. The goal was to have an ideal aesthetic model and compare the disparity between this model and a patient's reality. This could prove helpful during leg sculpturing to get closer to this ideal. Postoperatively, the result could then be compared to the ideal curves of the model legs and any remaining deviations from the ideal curves could be pointed out and eventually corrected in a second session. The lack of anthropometric studies of legs from the knee to the ankle led the author to select and study attractive legs to find out the common denominators of their beauty. The study consisted in analyzing the features that make legs look attractive. The legs of models in magazines were scanned and inserted into a PowerPoint program. The legs of live models, Barbie dolls, and athletes were photographed. Artistic drawings by Leonardo da Vinci were reviewed and Greek sculptures studied. Sculptures from the National Archaeological Museum of Athens were photographed and included in the PowerPoint program. This study shows that the first criterion for beautiful legs is the straightness of the leg column. Not a single attractive leg was found to deviate from the vertical, and each was in absolute continuity with the thigh. The second criterion is the similarity of curve distribution and progression from knee to ankle. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors at www.springer.com/00266.

Mutation induction in haploid yeast after split-dose radiation exposure. II. Combination of UV-irradiation and X-rays.

PubMed

Keller, B; Zölzer, F; Kiefer, J

2004-01-01

Split-dose protocols can be used to investigate the kinetics of recovery from radiation damage and to elucidate the mechanisms of cell inactivation and mutation induction. In this study, a haploid strain of the yeast, Saccharomyces cerevisiae, wild-type with regard to radiation sensitivity, was irradiated with 254-nm ultraviolet (UV) light and then exposed to X-rays after incubation for 0-6 hr. The cells were incubated either on nutrient medium or salt agar between the treatments. Loss of reproductive ability and mutation to canavanine resistance were measured. When the X-ray exposure immediately followed UV-irradiation, the X-ray survival curves had the same slope irrespective of the pretreatment, while the X-ray mutation induction curves were changed from linear to linear quadratic with increasing UV fluence. Incubations up to about 3 hr on nutrient medium between the treatments led to synergism with respect to cell inactivation and antagonism with respect to mutation, but after 4-6 hr the two treatments acted independently. Incubation on salt agar did not cause any change in the survival curves, but there was a strong suppression of X-ray-induced mutation with increasing UV fluence. On the basis of these results, we suggest that mutation after combined UV and X-ray exposure is affected not only by the induction and suppression of DNA repair processes, but also by radiation-induced modifications of cell-cycle progression and changes in the expression of the mutant phenotype. Copyright 2004 Wiley-Liss, Inc.

Increased level of annexin A1 in bronchoalveolar lavage fluid as a potential diagnostic indicator for lung cancer.

PubMed

Biaoxue, Rong; Xiguang, Cai; Hua, Liu; Tian, Fu; Wenlong, Gao

2017-03-02

Annexin A1 has been implicated in various tumor types, but few studies have investigated its involvement in lung cancer. The purpose of this investigation was to quantify the annexin A1 level in bronchoalveolar lavage fluid (BALF) and analyze its usefulness in lung cancer diagnosis. Annexin A1 expression was measured by immunohistochemistry and enzyme immunoassay. The sensitivity and specificity of annexin A1 for distinguishing lung cancer were determined by receiver operator characteristic (ROC) curves. Tumor tissues, BALF and serum of patients with lung cancer contained higher levels of annexin A1 than those of the control group of patients with benign lung diseases. Moreover, an increased level of BALF annexin A1 was closely correlated with lymphatic invasion and malignant progression of lung cancer. The sensitivity and specificity of BALF annexin A1 for distinguishing lung cancer were 94.2% and 90.2%, respectively. Increased annexin A1 in BALF was correlated with lymphatic invasion and malignant progression of lung cancer, suggesting that it could be an indicator for discerning lung cancer and predicting outcome.

A Progressive Damage Model for Predicting Permanent Indentation and Impact Damage in Composite Laminates

NASA Astrophysics Data System (ADS)

Ji, Zhaojie; Guan, Zhidong; Li, Zengshan

2017-10-01

In this paper, a progressive damage model was established on the basis of ABAQUS software for predicting permanent indentation and impact damage in composite laminates. Intralaminar and interlaminar damage was modelled based on the continuum damage mechanics (CDM) in the finite element model. For the verification of the model, low-velocity impact tests of quasi-isotropic laminates with material system of T300/5228A were conducted. Permanent indentation and impact damage of the laminates were simulated and the numerical results agree well with the experiments. It can be concluded that an obvious knee point can be identified on the curve of the indentation depth versus impact energy. Matrix cracking and delamination develops rapidly with the increasing impact energy, while considerable amount of fiber breakage only occurs when the impact energy exceeds the energy corresponding to the knee point. Predicted indentation depth after the knee point is very sensitive to the parameter μ which is proposed in this paper, and the acceptable value of this parameter is in range from 0.9 to 1.0.

Capturing transitions and trajectories: the role of socioeconomic status in later life disability.

PubMed

Taylor, Miles G

2010-11-01

Disability is conceptualized as a life course process and measured using either transitions or trajectories. Previous research does not simultaneously explore both aspects of disablement, accounting for timing and trajectory. The role of education is noted in disability research, but its independent effects over time have not been fully examined. I investigate the effects of education and income on disability onset and progression over a decade. I use a latent curve modeling approach with four waves of the Duke Established Populations for Epidemiologic Studies of the Elderly data to independently test the preventive and mediating effects education and income provide for disability. Education has a preventive effect for disability onset but no significant effect on progression once income is held constant. Income has both a preventive and mediating effect on disability, although preventive effects are stronger for education. Later life disability is measured here using both onset and trajectory. Findings are consistent with health research suggesting that education and income work through shared and independent mechanisms to affect disability over time. These findings also highlight the importance of modeling timing when studying health trajectories.

Challenges and progress in making DNA-based AIS early ...

EPA Pesticide Factsheets

The ability of DNA barcoding to find additional species in hard-to-sample locations or hard-to-identify samples is well established. Nevertheless, adoption of DNA barcoding into regular monitoring programs has been slow, in part due to issues of standardization and interpretation that need resolving. In this presentation, we describe our progress towards incorporating DNA-based identification into broad-spectrum aquatic invasive species early-detection monitoring in the Laurentian Great Lakes. Our work uses community biodiversity information as the basis for evaluating survey performance for various taxonomic groups. Issues we are tackling in bringing DNA-based data to bear on AIS monitoring design include: 1) Standardizing methodology and work flow from field collection and sample handling through bioinformatics post-processing; 2) Determining detection sensitivity and accounting for inter-species differences in DNA amplification and primer affinity; 3) Differentiating sequencing and barcoding errors from legitimate new finds when range and natural history information is limited; and 4) Accounting for the different nature of morphology- vs. DNA-based biodiversity information in subsequent analysis (e.g., via species accumulation curves, multi-metric indices). not applicable

Recent advances and product enhancements in reflective cholesteric displays

NASA Astrophysics Data System (ADS)

Khan, Asad; Schneider, Tod; Miller, Nick; Marhefka, Duane; Ernst, Todd; Nicholson, Forrest; Doane, Joseph W.

2005-04-01

Bistable reflective cholesteric displays are a liquid crystal display technology developed to fill a market need for very low power displays on a low-cost, high resolution passive matrix. Their unique look, high reflectivity, bistability, and simple structure make them an ideal flat panel display choice for handheld or other portable devices where small lightweight batteries with long lifetimes are important. We discuss recent advances in cholesteric display technology at Kent Displays such as progress towards single layer black and white displays, standard products, lower cost display modules, and various interface options for cholesteric display applications. It will be shown that inclusion of radio frequency (rf) control options and serial peripheral interface (spi) can greatly enhance the cholesteric display module market penetration by enabling quick integration into end devices. Finally, some discussion will be on the progress of the development of flexible reflective cholesteric displays. These flexible displays can dramatically change industrial design methods by enabling curved surfaces with displays integrated in them. Additional discussion in the paper will include applications of various display modes including signs, hand held instrumentation, and the electronic book and reader.

Colonization and Disappearance of Mytilus galloprovincialisLam. on an Artificial Habitat in the Mediterranean Sea

NASA Astrophysics Data System (ADS)

Ardizzone, G. D.; Belluscio, A.; Gravina, M. F.; Somaschini, A.

1996-12-01

A Mytilus galloprovincialispopulation, settled on a new artificial habitat at 12 m depth in the Central Tyrrhenian Sea, was investigated for 10 years. The new substratum, located at a depth lower than the preferential range of the species, was colonized temporarily by mussels which reached very high densities and dominated the benthic community from their colonization until the third year. The length-frequency distribution analysis showed a progressively complex population structure with up to three cohorts. The yearly recruitments were observed once a year in spring. The growth curve provided a maximum length higher than that reported for shallow waters. Nevertheless, the gregarious habits of mussels and the reduced water movement caused edaphic modifications of the substratum, which was covered progressively by sediments and biodeposits (pseudofaeces). Consequently, the population structure was affected by a reduction of the newly recruited cohorts, and mussels disappeared after 5 years of colonization. This may be explained by the reduction in the substratum available for the first settlement (hydroid covering), as well as by the modification of the surface required for final settlement.

Electronic spectroscopy of UO(2)Cl(2) isolated in solid Ar.

PubMed

Jin, Jin; Gondalia, Raj; Heaven, Michael C

2009-11-12

Laser-induced fluorescence spectra have been recorded for uranyl chloride isolated in a solid Ar matrix. Pulsed excitation was examined using a XeCl excimer laser (308 nm) and a dye laser operating in the 19500-27500 cm-1 range. Several absorption and emission band systems were observed. The emission spectra were characterized by a nearly harmonic vibrational progression with a frequency of 840 cm-1 starting at 20323 cm-1. The electronic absorption spectra were dominated by five harmonic vibrational progressions with frequencies of approximately 710 cm-1. Comparisons with theoretical calculations indicate that all of the transitions observed were associated with the UO2+2 subunit. They involved the promotion of an electron from a bonding orbital to the metal-centered 5f(delta) and 5f(phi) orbitals. Band origins and vibrational constants for five excited states were obtained. Fluorescence was observed from the lowest-energy excited state alone, regardless of the excitation wavelength. The decay curve was found to be biexponential, with characteristic decay lifetimes of 50 and 260 micros.

The development and utility of a novel scale that quantifies the glycemic progression toward type 1 diabetes over 6 months.

PubMed

Sosenko, Jay M; Skyler, Jay S; Beam, Craig A; Boulware, David; Mahon, Jeffrey L; Krischer, Jeffrey P; Greenbaum, Carla J; Rafkin, Lisa E; Matheson, Della; Herold, Kevan C; Palmer, Jerry P

2015-05-01

We developed a scale to serve as a potential end point for 6-month glycemic progression (PS6M) toward type 1 diabetes (T1D) in autoantibody-positive relatives of individuals with T1D. The PS6M was developed from Diabetes Prevention Trial-Type 1 (DPT-1) data and tested in the TrialNet Pathway to Prevention Study (PTP). It is the difference between 6-month glucose sum values (30-120 min oral glucose tolerance test values) and values predicted for nonprogressors. The PS6M predicted T1D in the PTP (P < 0.001). The area under the receiver operating chacteristic curve was greater (P < 0.001) for the PS6M than for the baseline-to-6-month difference. PS6M values were higher in those with two or more autoantibodies, 30-0 min C-peptide values <2.00 ng/mL, or DPT-1 Risk Scores >7.00 (P < 0.001 for all). The PS6M is an indicator of short-term glycemic progression to T1D that could be a useful tool for assessing preventive treatments and biomarkers. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

Energy Absorption in Chopped Carbon Fiber Compression Molded Composites

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

Starbuck, J.M.

2001-07-20

In passenger vehicles the ability to absorb energy due to impact and be survivable for the occupant is called the ''crashworthiness'' of the structure. To identify and quantify the energy absorbing mechanisms in candidate automotive composite materials, test methodologies were developed for conducting progressive crush tests on composite plate specimens. The test method development and experimental set-up focused on isolating the damage modes associated with the frond formation that occurs in dynamic testing of composite tubes. Quasi-static progressive crush tests were performed on composite plates manufactured from chopped carbon fiber with an epoxy resin system using compression molding techniques. Themore » carbon fiber was Toray T700 and the epoxy resin was YLA RS-35. The effect of various material and test parameters on energy absorption was evaluated by varying the following parameters during testing: fiber volume fraction, fiber length, fiber tow size, specimen width, profile radius, and profile constraint condition. It was demonstrated during testing that the use of a roller constraint directed the crushing process and the load deflection curves were similar to progressive crushing of tubes. Of all the parameters evaluated, the fiber length appeared to be the most critical material parameter, with shorter fibers having a higher specific energy absorption than longer fibers. The combination of material parameters that yielded the highest energy absorbing material was identified.« less

Value of semen parameters, with special reference to TNF-α, in predicting the quality of boar semen after short-term storage.

PubMed

Mrkun, Janko; Kosec, Marjan; Zrimšek, Petra

2013-06-01

The aim of this study was to address the question whether changes in boar semen quality after short-term storage could be predicted on the basis of standard semen parameters and TNF-α level determined on the day of semen collection under commercial conditions. Progressive motility showed the highest positive correlation with morphology on day 0 of collection, and progressive motility on day 3 (P < 0.05) showed a negative correlation with acrosome abnormalities (P < 0.05). According to the area under receiver operating characteristics (ROC) curves (AUCs), progressive motility could also be used in predicting semen quality after 3 days of storage (AUC > 0.5; P < 0.05). TNF-α in seminal plasma is the only parameter measured on day 0 to show a significant correlation with the percentage of viable spermatozoa after 3 days of semen storage (r = 0.495, P < 0.05). ROC analysis shows that TNF-α level is helpful in discriminating viability outcome after semen storage (AUC = 0.94, P < 0.001). We can predict with 92.35% certainty that fresh semen samples with more than 150 pg/ml of TNF-α in the seminal plasma will retain more than 85% of viable spermatozoa after 3 days of storage. Thus, TNF-α can contribute to predicting the quality of short-term stored semen.

Plasma Biomarkers Discriminate Clinical Forms of Multiple Sclerosis

PubMed Central

Tejera-Alhambra, Marta; Casrouge, Armanda; de Andrés, Clara; Seyfferth, Ansgar; Ramos-Medina, Rocío; Alonso, Bárbara; Vega, Janet; Fernández-Paredes, Lidia; Albert, Matthew L.; Sánchez-Ramón, Silvia

2015-01-01

Multiple sclerosis, the most common cause of neurological disability in young population after trauma, represents a significant public health burden. Current challenges associated with management of multiple sclerosis (MS) patients stem from the lack of biomarkers that might enable stratification of the different clinical forms of MS and thus prompt treatment for those patients with progressive MS, for whom there is currently no therapy available. In the present work we analyzed a set of thirty different plasma cytokines, chemokines and growth factors present in circulation of 129 MS patients with different clinical forms (relapsing remitting, secondary progressive and primary progressive MS) and 53 healthy controls, across two independent cohorts. The set of plasma analytes was quantified with Luminex xMAP technology and their predictive power regarding clinical outcome was evaluated both individually using ROC curves and in combination using logistic regression analysis. Our results from two independent cohorts of MS patients demonstrate that the divergent clinical and histology-based MS forms are associated with distinct profiles of circulating plasma protein biomarkers, with distinct signatures being composed of chemokines and growth/angiogenic factors. With this work, we propose that an evaluation of a set of 4 circulating biomarkers (HGF, Eotaxin/CCL11, EGF and MIP-1β/CCL4) in MS patients might serve as an effective tool in the diagnosis and more personalized therapeutic targeting of MS patients. PMID:26039252

Association between high levels of Notch3 expression and high invasion and poor overall survival rates in pancreatic ductal adenocarcinoma.

PubMed

Zhou, Jin-Xue; Zhou, Liang; Li, Qing-Jun; Feng, Wen; Wang, Pei-Min; Li, Er-Feng; Gong, Wen-Jing; Kou, Ming-Wen; Gou, Wei-Ting; Yang, Yan-Ling

2016-11-01

Pancreatic ductal adenocarcinoma (PDAC) is a commonly fatal tumour. It is characterized by early metastasis and high mortality. Many patients die as a result of PDAC tumour progression. However, the underlying mechanism of invasion and metastasis in PDAC is still not fully understood. Previous studies showed that the Notch signalling pathway may play an important role in the progression of tumour invasion and metastasis. However, it is not yet known whether the Notch signalling pathway participates in the progression of invasion in PDAC. In the present study, immunohistochemistry showed that a high expression of Notch3 was correlated with tumour grade, metastasis, venous invasion and American Joint Committee on Cancer (AJCC) tumor-node-metastasis (TNM) stage. Kaplan-Meier curves suggested that a high expression of Notch3 was a significant risk factor for shortened survival time. We also showed that inhibition of Notch3 had an anti‑invasion role in PDAC cells. In vitro, the inhibition of Notch3 reduced the migration and invasion capabilities of PDAC cells by regulating the expressions of E-cadherin, CD44v6, MMP-2, MMP-9, VEGF and uPA via regulating the COX-2 and ERK1/2 pathways. These results indicated that downregulation of the Notch signalling pathway may be a novel and useful approach for preventing and treating PDAC invasion.