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Sample records for axis factoring method

  1. ScaphoLunate Axis Method.

    Science.gov (United States)

    Yao, Jeffrey; Zlotolow, Dan A; Lee, Steve K

    2016-03-01

    Background Treating chronic scapholunate ligament injuries without the presence of arthritis remains an unsolved clinical problem facing wrist surgeons. This article highlights a technique for reconstructing the scapholunate ligament using novel fixation, the ScaphoLunate Axis Method (SLAM). Materials and Methods In a preliminary review of the early experience of this technique, 13 patients were evaluated following scapholunate ligament reconstruction utilizing the SLAM technique. Description of Techinque The scapholunate interval is reconstructed utilizing a palmaris longus autograft passed between the scaphoid and lunate along the axis of rotation in the sagittal plane. It is secured in the lunate using a graft anchor and in the scaphoid utilizing an interference screw. The remaining graft is passed dorsally to reconstruct the dorsal scapholunate ligament. Results At an average follow-up of 11 months, the mean postoperative scapholunate gap was 2.1 mm. The mean postoperative scapholunate angle was 59 degrees. The mean postoperative wrist flexion and extension was 45 and 56 degrees, respectively. The mean grip strength was 24.9 kg, or 62% of the contralateral side. The mean pain score (VAS) was 1.7. There was 1 failure with recurrence of the pathologic scapholunate gap and the onset of pain. Conclusion While chronic scapholunate ligament instability remains an unsolved problem facing wrist surgeons, newer techniques are directed toward restoring the normal relationships of the scaphoid and lunate in both the coronal and sagittal planes. The SLAM technique has demonstrated promise in preliminary clinical studies. PMID:26855838

  2. Analyzing ground ozone formation regimes using a principal axis factoring method: A case study of Kladno (Czech Republic) industrial area

    Energy Technology Data Exchange (ETDEWEB)

    Malec, L.; Skacel, F. [Department of Gas, Coke and Air Protection, Institute of Chemical Technology in Prague, (Czech Republic)]. E-mail: Lukas.Malec@vscht.cz; Fousek, T. [Institute of Public Health, District of Central Czech Republic, Kladno (Czech Republic); Tekac, V. [Department of Gas, Coke and Air Protection, Institute of Chemical Technology in Prague, (Czech Republic); Kral, P. [Institute of Public Health, District of Central Czech Republic, Kladno (Czech Republic)

    2008-07-15

    Tropospheric ozone is a secondary air pollutant, changes in the ambient content of which are affected by both, the emission rates of primary pollutants and the variability of meteorological conditions. In this paper, we use two multivariate statistical methods to analyze the impact of the meteorological conditions associated with pollutant transformation processes. First, we evaluated the variability of the spatial and temporal distribution of ozone precursor parameters by using discriminant analysis (DA) in locations close to the industrial area of Kladno (a city in the Czech Republic). Second, we interpreted the data set by using factor analysis (FA) to examine the differences between ozone formation processes in summer and in winter. To avoid temperature dependency between the variables, as well as to describe tropospheric washout processes, we used water vapour content rather than the more commonly employed relative humidity parameter. In this way, we were able to successfully determine and subsequently evaluate the various processes of ozone formation, together with the distribution of ozone precursors. High air temperature, radiation and low water content relate to summer pollution episodes, while radiation and wind speed prove to be the most important parameters during winter. [Spanish] El ozono troposferico es un contaminante fotoquimico secundario cuyos contenidos estan influidos tanto por las razones de emision de las sustancias contaminantes primarias como por la variabilidad de las condiciones meteorologicas. En este trabajo utilizamos dos metodos estadisticos multivariados para el analisis de la influencia de las condiciones meteorologicas relacionadas con los procesos de transformacion de las sustancias contaminantes. Primero, estimamos la variabilidad de la descomposicion espacial y temporal de los precursores de ozono mediante el analisis discriminante (DA) en las areas cercanas a la zona industrial de Kladno (una ciudad de la Republica Checa

  3. Growth Hormone-Insulin-Like Growth Factor Axis, Thyroid Axis, Prolactin, and Exercise.

    Science.gov (United States)

    Hackney, Anthony C; Davis, Hope C; Lane, Amy R

    2016-01-01

    This chapter addresses what is known about the endocrine system components growth hormone (GH)-insulin-like growth factor (IGF) axis, thyroid axis, and prolactin relative to exercise and exercise training. Each one of these hormone axes contributes to the maintenance of homeostasis in the body through impact on a multitude of physiological systems. The homeostatic disruption of exercise causes differing responses in each hormone axis. GH levels increase with sufficient stimulation, and IGFs are released in response to GH from the anterior pituitary providing multiple roles including anabolic properties. Changes in the thyroid hormones T3 and T4 vary greatly with exercise, from increases/decreases to no change in levels across different exercise types, intensities and durations. These ambiguous findings could be due to numerous confounding factors (e.g. nutrition status) within the research. Prolactin increases proportionally to the intensity of the exercise. The magnitude may be augmented with extended durations; conflicting findings have been reported with resistance training. While the responses to exercise vary, it appears there may be overall adaptive and regenerative impacts on the body into recovery by these hormones through immune and tissue inflammatory responses/mediations. Nonetheless, well-designed exercise research studies are still needed on each of these hormones, especially thyroid hormones and prolactin. PMID:27348437

  4. A Method for Modeling of Floating Vertical Axis Wind Turbine

    DEFF Research Database (Denmark)

    Wang, Kai; Hansen, Martin Otto Laver; Moan, Torgeir

    2013-01-01

    It is of interest to investigate the potential advantages of floating vertical axis wind turbine (FVAWT) due to its economical installation and maintenance. A novel 5MW vertical axis wind turbine concept with a Darrieus rotor mounted on a semi-submersible support structure is proposed in this paper....... In order to assess the technical and economic feasibility of this novel concept, a comprehensive simulation tool for modeling of the floating vertical axis wind turbine is needed. This work presents the development of a coupled method for modeling of the dynamics of a floating vertical axis wind turbine....... This integrated dynamic model takes into account the wind inflow, aerodynamics, hydrodynamics, structural dynamics (wind turbine, floating platform and the mooring lines) and a generator control. This approach calculates dynamic equilibrium at each time step and takes account of the interaction between the rotor...

  5. Contribution to the method for determining femoral neck axis

    Directory of Open Access Journals (Sweden)

    Anđelković Zoran

    2014-01-01

    Full Text Available Introduction. Femoral neck axis plotting is of great significance in measuring parameters that define femoral head-neck junction sphericity in the group of patients with the femoroacetabular impingement. Literature methods of femoral neck axis determination have weaknesses associated with the risk of obtaining inaccurate values of certain parameters. Objective. Method of plotting of the femoral neck axis by two parallel lines that belong to the medial quarter of the femoral neck is proposed. Method was tested on the anatomic specimens and the respective radiograms. Methods. A total of 31 anatomic specimens of the proximal femur and respective radiographs were used, on which three axes of the femoral neck were plotted; accordingly, alpha angle value was determined and tested with corresponding parametric tests, with the measurement error of less than 5% and the strength of the applied tests of 80%. Results. Alpha angle values obtained by plotting femoral neck axis using the literature and methods we have proposed were not significantly different in our series, and, in more than a half of the specimens, the two axes overlapped each other. Conclusion. The advantage of the proposed method does not depend on the position of the femoral head rotation center in relation to the femoral neck, which favors proposed method for measuring the angles of femoral head sphericity in patients with the femoral head translation. Disadvantage of the study is a small sample size for valid conclusions about the applicability of this method in clinical practice.

  6. Off-axis angular spectrum method with variable sampling interval

    Science.gov (United States)

    Kim, Yong-Hae; Byun, Chun-Won; Oh, Himchan; Pi, Jae-Eun; Choi, Ji-Hun; Kim, Gi Heon; Lee, Myung-Lae; Ryu, Hojun; Hwang, Chi-Sun

    2015-08-01

    We proposed a novel off-axis angular spectrum method (ASM) for simulating free space wave propagation with a large shifted destination plane. The off-axis numerical simulation took wave propagation between a parallel source and a destination plane, but a destination plane was shifted from a source plane. The shifted angular spectrum method was proposed for diffraction simulation with a shifted destination plane and satisfied the Nyquist condition for sampling by limiting a bandwidth of a propagation field to avoid an aliasing error due to under sampling. However, the effective sampling number of the shifted ASM decreased when the shifted distance of the destination plane was large which caused a numerical error in the diffraction simulation. To compensate for the decrease of an effective sampling number for the large shifted destination plane, we used a variable sampling interval in a Fourier space to maintain the same effective sampling number independent of the shifted distance of the destination plane. As a result, our proposed off-axis ASM with a variable sampling interval can produce simulation results with high accuracy for nearly every shifted distance of a destination plane when an off-axis angle is less than 75°. We compared the performances of the off-axis ASM using the Chirp Z transform and non-uniform FFT for implementing a variable spatial frequency in a Fourier space.

  7. Efficient Path Query and Reasoning Method Based on Rare Axis

    Institute of Scientific and Technical Information of China (English)

    姜洋; 冯志勇; 王鑫马晓宁

    2015-01-01

    A new concept of rare axis based on statistical facts is proposed, and an evaluation algorithm is designed thereafter. For the nested regular expressions containing rare axes, the proposed algorithm can reduce its evaluation complexity from polynomial time to nearly linear time. The distributed technique is also employed to construct the navigation axis indexes for resource description framework (RDF) graph data. Experiment results in DrugBank and BioGRID show that this method can improve the query efficiency significantly while ensuring the accuracy and meet the query requirements on Web-scale RDF graph data.

  8. Moving Object Detection Using Graph’s Axis Change Method

    Directory of Open Access Journals (Sweden)

    Gagandeep Kaur

    2012-03-01

    Full Text Available The detection and identify moving objects in a video sequence is very important concept. The currently available techniques for motion estimation can be broadly categorized into main classes: block matching methods and optical flow methods. But here detection of moving objects is detected by using Graph’s axis change method. Here we convert the image in to pixels and then calculate the values when the pixel change its position according to x axis and y axis. There is no problem of fixed and movable background. This paper investigates the different motion estimation algorithms used for video processing applications. Among the available motion estimation methods, the Lucas kanade Algorithm using changed axis’s method has been used in this paper for detection of moving objects in a video sequence. The algorithm produces the result of Horizontal and Vertical components velocity, u and v respectively. This velocity is measured in the form of vectors and has been used to segment the moving objects from the video sequence. The algorithm has been applied to different sets of synthetic and real video sequence.

  9. ANALYSIS OF METHOD FOR DETERMINING AZIMUTH OF PRINCIPAL AXIS OF INERTIA BASED ON DYNAMIC BALANCE MEASUREMENT

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jun; GUAN Yingzi; QI Naiming

    2006-01-01

    The dynamic balance quality of a rotating object is an important factor to maintain the stability and accuracy for motion. The azimuth of the principal axis of inertia is a major sign of dynamic balance. A usual method is measuring moment of inertia matrix relative to some base coordinates on a rotary inertia machine so as to calculate the azimuth of principal axis of inertia. By using the measured unbalance results on the two trimmed planes on a vertical hard bearing double-plane dynamic balancing machine, the dimension and direction of couple unbalance can be found. An azimuth angle formula for the principal axis of inertia is derived and is solved by using unbalance quantities. The experiments indicate that method based on dynamic balancing measurement is proved rational and effective and has a fine precision.

  10. MOTION ERROR ESTIMATION OF5-AXIS MACHINING CENTER USING DBB METHOD

    Institute of Scientific and Technical Information of China (English)

    CHEN Huawei; ZHANG Dawei; TIAN Yanling; ICHIRO Hagiwara

    2006-01-01

    In order to estimate the motion errors of 5-axis machine center, the double ball bar (DBB)method is adopted to realize the diagnosis procedure. The motion error sources of rotary axes in 5-axis machining center comprise of the alignment error of rotary axes and the angular error due to various factors, e.g. the inclination of rotary axes. From sensitive viewpoints, each motion error is possible to have a particular sensitive direction in which deviation of DBB error trace arises from only some specific error sources. The model of the DBB error trace is established according to the spatial geometry theory. Accordingly, the sensitive direction of each motion error source is made clear through numerical simulation, which is used as the reference patterns for rotational error estimation.The estimation method is proposed to easily estimate the motion error sources of rotary axes in quantitative manner. To verify the proposed DBB method for rotational error estimation, the experimental tests are carried out on a 5-axis machining center M-400 (MORISEIKI). The effect of the mismatch of the DBB is also studied to guarantee the estimation accuracy. From the experimental data, it is noted that the proposed estimation method for 5-axis machining center is feasible and effective.

  11. A sensitive method of determining optic axis azimuth based on laser feedback

    International Nuclear Information System (INIS)

    A sensitive method to determine the optic axis azimuth of the birefringence element is presented, which is based on laser feedback. The phase difference between the two intensities in birefringence feedback changes with the angle between the optic axis of the birefringence element and laser original polarization. The phase difference is highly sensitive to the relative position of the optic axis and the laser original polarization. This method is used to highly precisely determine the optic axis azimuth, and is able to distinguish between the fast axis and the slow axis of the birefringence element. Theoretical analysis and experimental results are both demonstrated. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  12. The growth hormone axis and insulin-like growth factors

    Directory of Open Access Journals (Sweden)

    Radosavljević Tatjana

    2005-01-01

    Full Text Available Introduction Growth is regulated by the interaction of environmental signals with endogenous neuroendocrine responses to the genetic programs that determine the body plan. The insulin-like growth factors (IGFs are integral components of multiple systems controlling both growth and metabolism. The IGF system The IGF system is thought to be more complex than other endocrine systems, as genes for six IGF-binding proteins (IGFBPs have been identified so far. The IGFs play a critical role in both cell cycle control and apoptosis, two functions involved in regulation of tumorigenesis. Insulin-like growth factor-I (IGF-I is essential for normal growth. Confirmation of the significance of IGF-I in human physiology was obtained by the discovery of a patient with intrauterine growth retardation and postnatal growth failure associated with a mutation in the IGF-1 gene. Stages of evolution of the somatomedin hypothesis The original somatomedin hypothesis postulated that somatic growth was regulated by growth hormone's (GH's stimulation of hepatic IGF-1 production, with IGF-1 acting in an endocrine fashion to promote growth. The dual effectors theory proposed an alternative view, involving direct effects by GH on peripheral tissues not mediated by IGF-1 and GH-stimulated local IGF-1 production for autocrine/paracrine action. It is now clear that G H stimulates the formation of ternary IGF binding complex, which stabilizes IGF-I in the serum.

  13. Polymorphisms in the insulin-like growth factor axis are associated with gastrointestinal cancer

    NARCIS (Netherlands)

    Ong, J.; Salomon, J.; Morsche, R.H.M. te; Roelofs, H.M.J.; Witteman, B.J.; Dura, P.; Lacko, M.; Peters, W.H.M.

    2014-01-01

    INTRODUCTION: Numerous factors influence the development of gastrointestinal (GI) cancer. The insulin-like growth factor (IGF) axis plays a role in embryonic and postnatal growth and tissue repair. Elevated levels of IGFs, low levels of IGF binding proteins (IGFBPs) and over-expression of IGF recept

  14. [Growth Hormone-Insulin Growth Factor I (GH-IGF-I) axis and growth].

    Science.gov (United States)

    Castell, A-L; Sadoul, J-L; Bouvattier, C

    2013-10-01

    Normal human linear growth results from an evolutionary process expressing the sum effect of multiple genes. The growth hormone (GH) - insulin like growth factor (IGF)-I axis is one of the main actors in the growth process. Defects in this axis can be responsible for short or tall stature. Short stature is defined as smaller than - 2 standard deviations (SD). It is a very common reason for consultation in pediatrics; indeed, 2.5 % of children are concerned. Multiple causes make diagnosis difficult. In this article, we detail the most common constitutional causes of small size, including those related to a defect in the GH-IGF-I axis. Then, we report, the first results of the clinical and genetic study conducted on 213 patients with gigantism. Tall stature is defined by a height superior to 2 SD. Finally, recent work linking epigenetics and growth - via signaling pathways of GH-IGF-I axis - will be presented.

  15. [Growth Hormone-Insulin Growth Factor I (GH-IGF-I) axis and growth].

    Science.gov (United States)

    Castell, A-L; Sadoul, J-L; Bouvattier, C

    2013-10-01

    Normal human linear growth results from an evolutionary process expressing the sum effect of multiple genes. The growth hormone (GH) - insulin like growth factor (IGF)-I axis is one of the main actors in the growth process. Defects in this axis can be responsible for short or tall stature. Short stature is defined as smaller than - 2 standard deviations (SD). It is a very common reason for consultation in pediatrics; indeed, 2.5 % of children are concerned. Multiple causes make diagnosis difficult. In this article, we detail the most common constitutional causes of small size, including those related to a defect in the GH-IGF-I axis. Then, we report, the first results of the clinical and genetic study conducted on 213 patients with gigantism. Tall stature is defined by a height superior to 2 SD. Finally, recent work linking epigenetics and growth - via signaling pathways of GH-IGF-I axis - will be presented. PMID:24356290

  16. Deflecting Easy-axis of Fe304 Single Crystal Nanowires by Magnetic-field-induced Method

    Institute of Scientific and Technical Information of China (English)

    W. Wang; S. Y. Wang

    2012-01-01

    In order to control the orientation of easy-axis of magnetic nanowires, FesO4 single crystal nanowires with easy-axis perpendicular to wire-axis were prepared successfully by means of a magnetic-field-induced method. Analysis of X-ray diffraction and electron diffraction pattern showed that there was a wide-angle deflection of easy-axis in the prepared Fe304 nanowires. A high saturation magnetization (82 emu/g) of the FesO4 nanowires was achieved at room temperature. The benefits and mechanism of the deflection of easy-axis from its wire-axis in FesO4 single crystal nanowires were discussed. The results are expected to broaden the magnetic properties of traditional ferrite nanowires.

  17. Role of the insulin-like growth factor 1 axis and visceral adiposity in oesophageal adenocarcinoma.

    LENUS (Irish Health Repository)

    Donohoe, C L

    2012-03-01

    Epidemiological studies have linked obesity with many cancers. The insulin-like growth factor (IGF) 1 axis may be an important mediator in obesity-associated cancer. This study examined the relationship between IGF-1 and its receptor (IGF-1R) in oesophageal adenocarcinoma, a cancer strongly linked to obesity.

  18. Model Correction Factor Method

    DEFF Research Database (Denmark)

    Christensen, Claus; Randrup-Thomsen, Søren; Morsing Johannesen, Johannes

    1997-01-01

    of the model correction factor method, is that in simpler form not using gradient information on the original limit state function or only using this information once, a drastic reduction of the number of limit state evaluation is obtained together with good approximations on the reliability. Methods...

  19. A new robust gradient-based method for detection of symmetry axis

    Science.gov (United States)

    Hu, Jing; Wan, Qinqi; Hu, Yongli

    2015-12-01

    Symmetry axis extraction is an important part of the image feature detection. So far, various classical symmetry axes extraction algorithms have been proposed, such as the minimum-inertia-axis-based method, the SIFT-based method. If the input image is blurry, or it's difficult to extract feature points or corner points from input images, however, the above algorithms are difficult to obtain satisfied results. This paper presents a gradient-based method that can robustly extract symmetry axis from visual pattern. The key points of our methods are gradient calculation, symmetric weight calculation, and Hough Transform. Our method was evaluated on several datasets, including both blurred and smooth-edged cases. Experimental results demonstrated that our method achieves a more robust performance than previous methods.

  20. Latent profile analysis and principal axis factoring of the DSM-5 dissociative subtype

    Directory of Open Access Journals (Sweden)

    Paul A. Frewen

    2015-04-01

    Full Text Available Objective: A dissociative subtype has been recognized based on the presence of experiences of depersonalization and derealization in relation to DSM-IV posttraumatic stress disorder (PTSD. However, the dissociative subtype has not been assessed in a community sample in relation to the revised DSM-5 PTSD criteria. Moreover, the 20-item PTSD Checklist for DSM-5 (PCL-5 currently does not assess depersonalization and derealization. Method: We therefore evaluated two items for assessing depersonalization and derealization in 557 participants recruited online who endorsed PTSD symptoms of at least moderate severity on the PCL-5. Results: A five-class solution identified two PTSD classes who endorsed dissociative experiences associated with either 1 severe or 2 moderate PTSD symptom severity (D-PTSD classes. Those in the severe dissociative class were particularly likely to endorse histories of childhood physical and sexual abuse. A principal axis factor analysis of the symptom list identified six latent variables: 1 Reexperiencing, 2 Emotional Numbing/Anhedonia, 3 Dissociation, 4 Negative Alterations in Cognition & Mood, 5 Avoidance, and 6 Hyperarousal. Conclusions: The present results further support the presence of a dissociative subtype within the DSM-5 criteria for PTSD.

  1. Insulin-like factor 3 (INSL3 and the HPG axis in the male

    Directory of Open Access Journals (Sweden)

    Richard eIvell

    2014-01-01

    Full Text Available The HPG (hypothalamo-pituitary-gonadal axis comprises pulsatile GnRH from the hypothalamus impacting on the anterior pituitary to induce expression and release of both LH and FSH into the circulation. These in turn stimulate receptors on testicular Leydig and Sertoli cells, respectively, to promote steroidogenesis and spermatogenesis. Both Leydig and Sertoli cells exhibit negative feedback to the pituitary and/or hypothalamus via their products testosterone and inhibin B, respectively, thereby allowing tight regulation of the HPG axis. In particular, LH exerts both acute control on Leydig cells by influencing steroidogenic enzyme activity, as well as chronic control by impacting on Leydig cell differentiation and gene expression. Insulin-like peptide 3 (INSL3 represents an additional and different endpoint of the HPG axis. This Leydig cell hormone interacts with specific receptors, called RXFP2, on Leydig cells themselves to modulate steroidogenesis, and on male germ cells, probably to synergize with androgen-dependent Sertoli cell products to support spermatogenesis. Unlike testosterone, INSL3 is not acutely regulated by the HPG axis, but is a constitutive product of Leydig cells, which reflects their number and/or differentiation status and their ability therefore to produce various factors including steroids, together this is referred to as Leydig cell functional capacity. Because INSL3 is not subject to the acute episodic fluctuations inherent in the HPG axis itself, it serves as an excellent marker for Leydig cell differentiation and functional capacity, as in puberty, or in monitoring the treatment of hypogonadal patients, and at the same time buffering the HPG output.

  2. Liver-spleen axis, insulin-like growth factor-(IGF-I axis and fat mass in overweight/obese females

    Directory of Open Access Journals (Sweden)

    Lombardi Gaetano

    2011-08-01

    Full Text Available Abstract Background Fat mass (FM in overweight/obese subjects has a primary role in determining low-grade chronic inflammation and, in turn, insulin resistance (IR and ectopic lipid storage within the liver. Obesity, aging, and FM influence the growth hormone/insulin-like growth factor (IGF-I axis, and chronic inflammation might reduce IGF-I signaling. Altered IGF-I axis is frequently observed in patients with Hepatic steatosis (HS. We tested the hypothesis that FM, or spleen volume and C-reactive protein (CRP--all indexes of chronic inflammation--could affect the IGF-I axis status in overweight/obese, independently of HS. Methods The study population included 48 overweight/obese women (age 41 ± 13 years; BMI: 35.8 ± 5.8 kg/m2; range: 25.3-53.7, who underwent assessment of fasting plasma glucose and insulin, homeostasis model assessment of insulin resistance (HOMA, cholesterol and triglycerides, HDL-cholesterol, transaminases, high-sensitive CRP, uric acid, IGF-I, IGF binding protein (BP-1, IGFBP-3, and IGF-I/IGFBP-3 ratio. Standard deviation score of IGF-I according to age (zSDS were also calculated. FM was determined by bioelectrical impedance analysis. HS severity grading (score 0-4 according liver hyperechogenicity and spleen longitudinal diameter (SLD were evaluated by ultrasound. Results Metabolic syndrome (MS and HS were present in 33% and 85% of subjects, respectively. MS prevalence was 43% in subjects with increased SLD. IGF-I values, but not IGF-I zSDS, and IGF-I/IGFBP-3 ratio were significantly lower, while FM%, FPI, HOMA, ALT, CRP, were significantly higher in patients with severe HS than in those with mild HS. IGF-I zSDS (r = -0.42, r = -0.54, respectively; p Conclusions The present study suggests that lower IGF-I status in our study population is associated with higher FM, SLD, CRP and more severe HS.

  3. Mechanical axis of the lower extremity determined by a new digital photographic method.

    Science.gov (United States)

    Simonsen, Ole Højgaard; Thomsen, Hanne; Skou, Søren Thorgaard; Andersen, Mikkel Meyer

    2013-08-01

    Assessment of the mechanical axis is routine during the examination of patients with lower extremity pain. Long-leg radiographic examination is the gold standard for exact measurement, but it is associated with a significant radiation dose. An alternative method to examine the mechanical axis has been warranted. This article validates a newly developed computerized photograph method to calculate the mechanical axis using a digital photograph. The location of the center of the femoral head was calculated using ink marks on both superior iliac spines. Twenty-five patients (10 women and 15 men) had both legs examined using the photographic method and long-leg radiography examination. The digital photograph method was found to be highly reliable. The interobserver absolute mean difference was 0.99°±0.85°, and the intraobserver absolute mean difference (day-to-day variation) was 1.04°±0.81°. The mechanical axis determined by the 2 methods was highly correlated (R=0.943). The long-leg radiography method was within an average of ±1.88° of the photographic method, with a 95% probability. The photographic method appears to be an effective alternative to conventional long-leg radiography. The photographic method seems convenient in the routine examination of patients with leg pain and children with suspected axial deformity and for follow-up after treatment for malalignment. Calculation coefficients for children and a possible racial difference remain to be studied.

  4. Polysomnographic sleep, growth hormone insulin-like growth factor-I axis, leptin, and weight loss

    DEFF Research Database (Denmark)

    Rasmussen, Michael; Wildschiødtz, Gordon; Juul, Anders;

    2008-01-01

    compared with nonobese subjects After diet-induced weight loss the differences in GH, free IGF-I, and leptin were no longer present between previously obese and nonobese subjects, whereas a significant difference in sleep duration and total IGF-I levels persisted. Rapid eye movement (REM) sleep, non-REM......Short sleep appears to be strongly associated with obesity and altered metabolic function, and sleep and growth hormone (GH) secretion seems interlinked. In obesity, both the GH-insulin-like-growth-factor-I (GH-IGF-I) axis and sleep have been reported to be abnormal, however, no studies have...... investigated sleep in relation to the GH-IGF-I axis and weight loss in obese subjects. In this study polygraphic sleep recordings, 24-h GH release, 24-h leptin levels, free-IGF-I, total-IGF-I, IGF-binding protein-3 (IGFBP-3), acid-labile subunit (ALS), cortisol and insulin sensitivity were determined in six...

  5. Recognition Method of Aircraft Axis Direction Based on Morphological Skeleton and Hough Transform

    Institute of Scientific and Technical Information of China (English)

    WANG Hong-bo; ZHUANG Zhi-hong; ZHENG Hua-li; ZHANG Qing-tai; HE Hong-jun

    2008-01-01

    Because of the limit of angle of view(AOV) of IR imaging seeker during the approach of missile and target, the detector can only get the partial image sequence of aircraft nose after "lose point". Recognizing the axis direction on the basis of partial IR image sequence is a key issue of the advanced IR imaging guide air-to-air missile faced. In this paper, a recognition method was proposed based on the morphological skeleton and modified Hough transform, and this method can recognize correctly the axis direction of aircraft nose in different poses during missile-target encounter. Firstly, the morphological skeleton transform was used for the extraction of skeleton features. Secondly, the modified Hough transform was used for the straight-lines detection. Finally, According to the relations between aircraft nose and axis and invariant of nose features in high-speed IR image sequence, the axis direction can be detected and calculated. Experimental results indicate that the method is feasible and effective, and the precision of axis direction recognized can meet the requirement of accurate burst control of GIF fuze.

  6. Evaluation of off-axis wedge correction factor using diode dosimeters for estimation of delivered dose in external radiotherapy

    Directory of Open Access Journals (Sweden)

    Mahmoud Allahverdi

    2012-01-01

    Full Text Available An in vivo dosimetry system, using p-type diode dosimeters, was characterized for clinical applications of treatment machines ranging in megavoltage energies. This paper investigates two different models of diodes for externally wedged beams and explains a new algorithm for the calculation of the target dose at various tissue depths in external radiotherapy. The values of off-axis wedge correction factors were determined at two different positions in the wedged (toward the thick and thin edges and in the non-wedged directions on entrance and exit surfaces of a polystyrene phantom in 60 Co and 6 MV photon beams. Depth transmission was defined on the entrance and exit surfaces to obtain the off-axis wedge correction factor at any depth. As the sensitivity of the diodes depends on physical characteristics [field size, source-skin distance (SSD, thickness, backscatter], correction factors were applied to the diode reading when measuring conditions different from calibration situations . The results indicate that needful correction factors for 60 Co wedged photons are usually larger than those for 6 MV wedged photon beams. In vivo dosimetry performed with the proposed algorithms at externally wedged beams has negligible probable errors (less than 0.5% and is a reliable method for patient dose control.

  7. Single Vector Calibration System for Multi-Axis Load Cells and Method for Calibrating a Multi-Axis Load Cell

    Science.gov (United States)

    Parker, Peter A. (Inventor)

    2003-01-01

    A single vector calibration system is provided which facilitates the calibration of multi-axis load cells, including wind tunnel force balances. The single vector system provides the capability to calibrate a multi-axis load cell using a single directional load, for example loading solely in the gravitational direction. The system manipulates the load cell in three-dimensional space, while keeping the uni-directional calibration load aligned. The use of a single vector calibration load reduces the set-up time for the multi-axis load combinations needed to generate a complete calibration mathematical model. The system also reduces load application inaccuracies caused by the conventional requirement to generate multiple force vectors. The simplicity of the system reduces calibration time and cost, while simultaneously increasing calibration accuracy.

  8. Effect of sericin on diabetic hippocampal growth hormone/insulin-like growth factor 1 axis***

    Institute of Scientific and Technical Information of China (English)

    Zhihong Chen; Songhe Yang; Yaqiang He; Chengjun Song; Yongping Liu

    2013-01-01

    Previous studies have shown that sericin extracted from silk cocoon significantly reduces blood glucose levels and protects the nervous system against diabetes mel itus. In this study, a rat type 2 diabetes mel itus model was established by intraperitoneal injection of 25 mg/kg streptozotocin for 3 successive days, fol owing which the rats were treated with sericin for 35 days. After treatment, the blood glucose levels of the diabetic rats decreased significantly, the growth hormone level in serum and its expression in the hippocampus decreased significantly, while the insulin-like growth factor-1 level in serum and insulin-like growth factor-1 and growth hormone receptor expression in the hippocampus increased significantly. The experimental findings indicate that sericin improves disorders of the growth hormone/insulin-like growth factor 1 axis to al eviate hippocampal damage in diabetic rats.

  9. Feasibility study on 3 axis magnetic sensor for flux leakage method

    Science.gov (United States)

    Sasamoto, Akira

    2014-04-01

    Most of NDT system by magnetic field sensing has employed coil or semiconductor as sensor which has one axis sensitivity. Recent development of semiconductor technology can makes a chip that enable us to measure 3 axis magnetic field in a 1mm square. This vector information is expected to show a new insight in NDT testing. This presentation will show a basic experimental feasibility study for application of magnetic sensor to flux leakage and eddy current testing method by using a sensing system with the chip.

  10. A Fast and High-Accuracy Compass Alignment Method to SINS with Azimuth Axis Rotation

    OpenAIRE

    Xixiang Liu; Xiaosu Xu; Yiting Liu; Lihui Wang

    2013-01-01

    Azimuth axis rotating modulation was introduced to improve the alignment accuracy of strapdown inertial navigation system (SINS) through compass algorithm, in which the limit accuracy was determined by equivalent sensor errors in the eastern and northern direction. In this modulation, horizontal sensor errors were modulated into zero mean periodic variables. Furthermore, two methods were introduced to ensure alignment accuracy and speed: (1) shortened rotating cycle and redesigned compass par...

  11. Insulin-like growth factor axis and risk of type 2 diabetes in women.

    Science.gov (United States)

    Rajpathak, Swapnil N; He, Meian; Sun, Qi; Kaplan, Robert C; Muzumdar, Radhika; Rohan, Thomas E; Gunter, Marc J; Pollak, Michael; Kim, Mimi; Pessin, Jeffrey E; Beasley, Jeannette; Wylie-Rosett, Judith; Hu, Frank B; Strickler, Howard D

    2012-09-01

    IGF-I shares structural homology and in vitro metabolic activity with insulin. Laboratory models suggest that IGF-I and its binding proteins IGFBP-1 and IGFBP-2 have potentially beneficial effects on diabetes risk, whereas IGFBP-3 may have adverse effects. We therefore conducted a prospective nested case-control investigation of incident diabetes (n = 742 case subjects matched 1:1 to control subjects) and its associations with IGF-axis protein levels in the Nurses' Health Study, a cohort of middle-aged women. The median time to diabetes was 9 years. Statistical analyses were adjusted for multiple risk factors, including insulin and C-reactive protein. Diabetes risk was fivefold lower among women with baseline IGFBP-2 levels in the top versus bottom quintile (odds ratio [OR](q5-q1) = 0.17 [95% CI 0.08-0.35]; P trend < 0.0001) and was also negatively associated with IGFBP-1 levels (OR(q5-q1) = 0.37 [0.18-0.73]; P trend = 0.0009). IGFBP-3 was positively associated with diabetes (OR(q5-q1) = 2.05 [1.20-3.51]; P trend = 0.002). Diabetes was not associated with total IGF-I levels, but free IGF-I and diabetes had a significant association that varied (P interaction = 0.003) by insulin levels above the median (OR(q5-q1) = 0.48 [0.26-0.90]; P trend = 0.0001) versus below the median (OR(q5-q1) = 2.52 [1.05-6.06]; P trend < 0.05). Thus, this prospective study found strong associations of incident diabetes with baseline levels of three IGFBPs and free IGF-I, consistent with hypotheses that the IGF axis might influence diabetes risk.

  12. Stability analysis of axi-symmetric shells by the finite element method, (2)

    International Nuclear Information System (INIS)

    Generally in case of the buckling of shells, the balanced load lowers rapidly after the buckling, and the maximum values are observed on the load-deflection curves. Snapping buckling occurs and stability is lost often at the much lower load than the theoretical linear buckling load. The buckling of shallow spherical shells is the typical example. In this paper, the method of dealing with the snapping buckling and bifurcation buckling of shells by the finite element method is described. Axi-symmetric deformation is taken into account in the equation for strain and deformation relationship used in this paper so that bifurcation buckling can be treated. Axi-symmetric shells are modeled as the assembly of truncated conical shells, and the equation for basis relation and the stiffness matrices used are same as those in the previous paper. The method of stepwise increasing load is used for the analysis. The eigenvalues of stiffness matrices can be utilized as the critical condition for the stability and instability of systems, accordingly they are analyzed. Taking the example of the buckling of shallow spherical shells subjected to uniform external pressure, snapping buckling and bifurcation buckling were analyzed. The computer program was developed, and the results of numerical calculation by this analysis were compared with the results by other researchers. The propriety of this analytical method was proved. (Kako, I.)

  13. An empirical and computational method for performance evaluation of vertical axis wind energy capture system

    Science.gov (United States)

    French, Jesse Jason

    This Dissertation presents the author's investigation and development of a systematic method for evaluating the aerodynamic performance of Vertical Axis Wind Energy Capture Systems (WECS) apart from their electrical generation capability. The current standard method for specifying a wind energy machine is to discuss its rated power in kilowatts (or megawatts when capacity exceeds 100 kW). While this holistic method is effective for comparing machines it does not reveal the essential characteristics necessary for optimization of individual machine components. The method developed herein separates the performance characteristics of the WECS from the generation characteristics and isolates them for benchmarking and optimization. In order to develop an evaluation criterion, it was essential to evaluate and benchmark the current state of the art for wind energy capture. A thorough history of Vertical Axis Wind Turbine (VAWT) development and technology transfer, a standardized set of VAWT terms and a complete taxonomy of WECS types are included to ensure comparisons remain appropriate and within the same class of machine. Existing analytical methods for WECS and wind energy airfoils are surveyed and appropriate methods are selected and presented for establishing lift, drag, solidity, and specific power. A novel technique is developed for more accurately calculating VAWT solidity and is presented along with the numerous historical methods for solidity calculation. Empirical methods are presented for characterizing advance ratio and aerodynamic coefficient of performance. Results show that a VAWT can be optimized aerodynamically without consideration of generator efficiency using low capital cost rapid prototyping methods and an unsophisticated open loop wind tunnel. Wind tunnel model production with a rapid prototyping machine and kilowatt scale prototyping using composite material fabrication are discussed. Fixed and mobile test tower design and instrumentation are

  14. Toolpath generation method for four-axis NC machining of helical rotor

    Directory of Open Access Journals (Sweden)

    J.N. Lee

    2008-12-01

    Full Text Available Purpose: This paper presented a method for generating the toolpaths for the machining of a helical rotor onfive-axis machine tool.Design/methodology/approach: The geometry of the helical rotor is designed based on the ruled surfaces.Through the homogeneous coordinate transformation, the cutter location of the flank milling for four-axismachining can be generated. The postprocessor are developed for converting the cutter location file to the fouraxisnumerical control program.Findings: The toolpath generated are verified through solid cutting simulation and a trial cut. The results showthat the proposed method is valid and the machining process works well.Practical implications: As a result, modeling based on ruled surface is frequently used in constructing curvedsurfaces for aerospace industry and precision mechanical parts such as spatial cams, turbines, dies and molds,rotors of pumps, and centrifugal impellers.Originality/value: This paper describes multi – axis toolpath generation using the flank milling method for thehelical rotor, the cutter location file can be generated with cylindrical and mill.

  15. Factorization Method in Quantum Mechanics

    CERN Document Server

    Dong, Shi-Hai

    2007-01-01

    This Work introduces the factorization method in quantum mechanics at an advanced level with an aim to put mathematical and physical concepts and techniques like the factorization method, Lie algebras, matrix elements and quantum control at the Reader’s disposal. For this purpose a comprehensive description is provided of the factorization method and its wide applications in quantum mechanics which complements the traditional coverage found in the existing quantum mechanics textbooks. Related to this classic method are the supersymmetric quantum mechanics, shape invariant potentials and group theoretical approaches. It is no exaggeration to say that this method has become the milestone of these approaches. In fact the Author’s driving force has been his desire to provide a comprehensive review volume that includes some new and significant results about the factorization method in quantum mechanics since the literature is inundated with scattered articles in this field, and to pave the Reader’s way into ...

  16. A vertical axis tracking method - theoretical consideration for photovoltaic systems at high latitude sites

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, G. R. K; Narasimba Rao, A. V; Subramanyam S [Department of Mechanical Engineering, Warangal (India)

    2000-07-01

    In photovoltaic power generation the photovoltaic array is the most cost intensive unit. In order to make the photovoltaic power competitive the array is to be loaded to its maximum capacity for the longer periods of time. One of the strategies to minimize the cosine effect is by tracking the device. In this paper a novel method of Vertical Axis tracking system with optimum tilt is described. Optimum tilt is obtained by weighting the beam radiation with the altitude of the sun over day. Oslo is chosen for the study because the system is better suited for places having higher latitudes. It is observed that the energy collected in the vertical axis tracking is almost equivalent to that of two-axis tracking mode at latitudes 66.7method offers mechanically simpler construction. The change in tracking angle in a year is 32 Celsius degrees , which is smaller compared to 47 Celsius degrees required for two-axis tracking. [Spanish] En la generacion de energia electrica fotovoltaica el arreglo fotovoltaico es la unidad mas costosa. Para hacer la energia electrica fotovoltaica competitiva el arreglo debe de ser cargado a su maxima capacidad por periodos de tiempo mas largos. Una de las estrategias para minimizar el efecto del coseno es haciendo que el dispositivo siga la trayectoria. En este articulo se describe un metodo novedoso de un sistema de seguimiento de eje vertical con inclinacion optima. La inclinacion optima se obtiene contrapesando la radiacion del rayo contra la altitud del sol durante el dia. Se escogio la Ciudad de Oslo para el estudio porque el sistema es mas adecuado para lugares que tienen altas latitudes. Se observa que la energia recolectada en el seguidor de eje vertical es casi equivalente al modo de rastreo de dos ejes a latitudes de 6.7< {phi}< 23.45. Este metodo ofrece una construccion mecanica mas simple, el cambio del angulo de rastreo en un ano es de 32 grados Celsius que es inferior si se compara con los 47grados Celsius

  17. Defining the knee joint flexion-extension axis for purposes of quantitative gait analysis: an evaluation of methods.

    Science.gov (United States)

    Schache, Anthony G; Baker, Richard; Lamoreux, Larry W

    2006-08-01

    Minimising measurement variability associated with hip axial rotation and avoiding knee joint angle cross-talk are two fundamental objectives of any method used to define the knee joint flexion-extension axis for purposes of quantitative gait analysis. The aim of this experiment was to compare three different methods of defining this axis: the knee alignment device (KAD) method, a method based on the transepicondylar axis (TEA) and an alternative numerical method (Dynamic). The former two methods are common approaches that have been applied clinically in many quantitative gait analysis laboratories; the latter is an optimisation procedure. A cohort of 20 subjects performed three different functional tasks (normal gait; squat; non-weight bearing knee flexion) on repeated occasions. Three-dimensional hip and knee angles were computed using the three alternative methods of defining the knee joint flexion-extension axis. The repeatability of hip axial rotation measurements during normal gait was found to be significantly better for the Dynamic method (pknee varus-valgus kinematic profile and the degree of knee joint angle cross-talk were smallest for the Dynamic method across all functional tasks. The Dynamic method therefore provided superior results in comparison to the KAD and TEA-based methods and thus represents an attractive solution for orientating the knee joint flexion-extension axis for purposes of quantitative gait analysis.

  18. A Fast and High-Accuracy Compass Alignment Method to SINS with Azimuth Axis Rotation

    Directory of Open Access Journals (Sweden)

    Xixiang Liu

    2013-01-01

    Full Text Available Azimuth axis rotating modulation was introduced to improve the alignment accuracy of strapdown inertial navigation system (SINS through compass algorithm, in which the limit accuracy was determined by equivalent sensor errors in the eastern and northern direction. In this modulation, horizontal sensor errors were modulated into zero mean periodic variables. Furthermore, two methods were introduced to ensure alignment accuracy and speed: (1 shortened rotating cycle and redesigned compass parameters were selected to eliminate or ease the amplification to low-frequency senor error inputs in compass loop caused by rotation and (2 a data repeated calculation method was designed to shorten prolonged alignment time caused by the above redesigned parameters. Based on a certain SINS, turntable test proves that alignment accuracy and time were significantly improved and slightly shortened in comparison with the classical compass alignment.

  19. Dual axis translation apparatus and system for translating an optical beam and related method

    Science.gov (United States)

    Cassidy, Kelly

    1991-01-01

    A dual axis translation device and system in accordance with this invention, for translating an optical beam along both an x-axis and a y-axis which are perpendicular to one another, has a beam directing means acting on said optical beam for directing the beam along a particular path transverse to said x and y axes. An arrangement supporting said beam directing means for movement in the x and y direction within a given plane is provided. The arrangement includes a first means for translating said beam directing means along the x-axis in said given plane in order to translate the beam along said x-axis. The arrangement comprises a second means for translating said beam directing means along the y-axis in said given plane in order to translate the beam along said y-axis.

  20. Growth inhibition of thyroid follicular cell-derived cancers by the opioid growth factor (OGF - opioid growth factor receptor (OGFr axis

    Directory of Open Access Journals (Sweden)

    Donahue Renee N

    2009-10-01

    Full Text Available Abstract Background Carcinoma of the thyroid gland is an uncommon cancer, but the most frequent malignancy of the endocrine system. Most thyroid cancers are derived from the follicular cell. Follicular carcinoma (FTC is considered more malignant than papillary thyroid carcinoma (PTC, and anaplastic thyroid cancer (ATC is one of the most lethal human cancers. Opioid Growth Factor (OGF; chemical term - [Met5]-enkephalin and its receptor, OGFr, form an inhibitory axis regulating cell proliferation. Both the peptide and receptor have been detected in a wide variety of cancers, and OGF is currently used clinically as a biotherapy for some non-thyroid neoplasias. This study addressed the question of whether the OGF-OGFr axis is present and functional in human thyroid follicular cell - derived cancer. Methods Utilizing human ATC (KAT-18, PTC (KTC-1, and FTC (WRO 82-1 cell lines, immunohistochemistry was employed to ascertain the presence and location of OGF and OGFr. The growth characteristics in the presence of OGF or the opioid antagonist naltrexone (NTX, and the specificity of opioid peptides for proliferation of ATC, were established in KAT-18 cells. Dependence on peptide and receptor were investigated using neutralization studies with antibodies and siRNA experiments, respectively. The mechanism of peptide action on DNA synthesis and cell survival was ascertained. The ubiquity of the OGF-OGFr axis in thyroid follicular cell-derived cancer was assessed in KTC-1 (PTC and WRO 82-1 (FTC tumor cells. Results OGF and OGFr were present in KAT-18 cells. Concentrations of 10-6 M OGF inhibited cell replication up to 30%, whereas NTX increased cell growth up to 35% relative to cultures treated with sterile water. OGF treatment reduced cell number by as much as 38% in KAT-18 ATC in a dose-dependent and receptor-mediated manner. OGF antibodies neutralized the inhibitory effects of OGF, and siRNA knockdown of OGFr negated growth inhibition by OGF. Cell survival

  1. An empirical method for calculating melt compositions produced beneath mid-ocean ridges: Application for axis and off-axis (seamounts) melting

    Science.gov (United States)

    Niu, Yaoling; Batiza, Rodey

    1991-12-01

    We present a new method for calculating the major element compositions of primary melts parental to mid-ocean ridge basalt (MORB). This model is based on the experimental data of Jaques and Green (1980), Falloon et al. (1988), and Falloon and Green (1987, 1988) which are ideal for this purpose. Our method is empirical and employs solid-liquid partition coefficients (Di) from the experiments. We empirically determine Di = ƒ(P,F) and use this to calculate melt compositions produced by decompression-induced melting along an adiabat (column melting). Results indicate that most MORBs can be generated by 10-20% partial melting at initial pressures (P0) of 12-21 kbar. Our primary MORB melts have MgO = 10-12 wt %. We fractionate these at low pressure to an MgO content of 8.0 wt % in order to interpret natural MORB liquids. This model allows us to calculate Po, Pƒ, To, Tƒ, and F for natural MORB melts. We apply the model to interpret MORB compositions and mantle upwelling patterns beneath a fast ridge (East Pacific Rise (EPR)8°N to 14°N), a slow ridge (mid-Atlantic Ridge (MAR) at 26°S), and seamounts near the EPR (Lament seamount chain). We find mantle temperature differences of up to 50°-60°C over distances of 30-50 km both across axis and along axis at the EPR. We propose that these are due to upward mantle flow in a weakly conductive (versus adiabatic) temperature gradient. We suggest that the EPR is fed by a wide (-100 km) zone of upwelling due to plate separation but has a central core of faster buoyant flow. An along-axis thermal dome between the Siqueiros transform and the 11°45' Overlapping Spreading center (OSC) may represent such an upwelling; however, in general there is a poor correlation between mantle temperature, topography, and the segmentation pattern at the EPR. For the Lament seamounts we find regular across-axis changes in Po and F suggesting that the melt zone pinches out off axis. This observation supports the idea that the EPR is fed by a

  2. An empirical method for calculating melt compositions produced beneath mid-ocean ridges: for axis and off-axis (seamounts) melting application

    Science.gov (United States)

    Batiza, Rodey

    1991-12-01

    We present a new method for calculating the major element compositions of primary melts parental to mid-ocean ridge basalt (MORB). This model is based on the experimental data of Jaques and Green (1980), Falloon et al. (1988), and Falloon and Green (1987, 1988) which are ideal for this purpose. Our method is empirical and employs solid-liquid partition coefficients (Di) from the experiments. We empirically determine Di=f(P,F) and use this to calculate melt compositions produced by decompression-induced melting along an adiabat (column melting). Results indicate that most MORBs can be generated by 10-20% partial melting at initial pressures (P0) of 12-21 kbar. Our primary MORB melts have MgO=10-12 wt %. We fractionate these at low pressure to an MgO content of 8.0 wt% in order to interpret natural MORB liquids. This model allows us to calculate Po, Pf, To, Tf, and F for natural MORB melts. We apply the model to interpret MORB compositions and mantle upwelling patterns beneath a fast ridge (East Pacific Rise (EPR) 8°N to 14°N), a slow ridge (mid-Atlantic Ridge (MAR) at 26°S), and seamounts near the EPR (Lamont seamount chain). We find mantle temperature differences of up to 50°-60°C over distances of 30-50 km both across axis and along axis at the EPR. We propose that these are due to upward mantle flow in a weakly conductive (versus adiabatic) temperature gradient. We suggest that the EPR is fed by a wide (~100 km) zone of upwelling due to plate separation but has a central core of faster buoyant flow. An along-axis thermal dome between the Siqueiros transform and the 11°45' Overlapping Spreading Center (OSC) may represent such an upwelling; however, in general there is a poor correlation between mantle temperature, topography, and the segmentation pattern at the EPR. For the Lamont seamounts we find regular across-axis changes in Po and F suggesting that the melt zone pinches out off axis. This observation supports the idea that the EPR is fed by a broad

  3. A 3-D aerodynamic method for the analysis of isolated horizontal-axis wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Ammara, I.; Masson, C.; Paraschivoiu, I. [Ecole Polytechnique, Montreal (Canada)

    1997-12-31

    In most existing performance-analysis methods, wind turbines are considered isolated so that interference effects caused by other rotors or by the site topography are neglected. The main objective of this paper is to propose a practical 3-D method suitable for the study of these effects, in order to optimize the arrangement and the positioning of Horizontal-Axis Wind Turbines (HAWTs) in a wind farm. In the proposed methodology, the flow field around isolated HAWTs is predicted by solving the 3-D, time-averaged, steady-state, incompressible, Navier-Stokes equations in which the turbines are represented by distributions of momentum sources. The resulting governing equations are solved using a Control-Volume Finite Element Method (CVFEM). The fundamental aspects related to the development of a practical 3-D method are discussed in this paper, with an emphasis on some of the challenges that arose during its implementation. The current implementation is limited to the analysis of isolated HAWTs. Preliminary results have indicated that, the proposed 3-D method reaches the same level of accuracy, in terms of performance predictions, that the previously developed 2-D axisymmetric model and the well-known momentum-strip theory, while still using reasonable computers resources. It can be considered as a useful tool for the design of HAWTs. Its main advantages, however, are its intrinsic capacity to predict the details of the flow in the wake, and its capabilities of modelling arbitrary wind-turbine arrangements and including ground effects.

  4. Transcription factor 7-like 1 is involved in hypothalamo–pituitary axis development in mice and humans

    Science.gov (United States)

    Gaston-Massuet, Carles; McCabe, Mark J.; Scagliotti, Valeria; Young, Rodrigo M.; Carreno, Gabriela; Gregory, Louise C.; Jayakody, Sujatha A.; Pozzi, Sara; Gualtieri, Angelica; Basu, Basudha; Koniordou, Markela; Wu, Chun-I; Bancalari, Rodrigo E.; Rahikkala, Elisa; Veijola, Riitta; Lopponen, Tuija; Graziola, Federica; Turton, James; Signore, Massimo; Mousavy Gharavy, Seyedeh Neda; Charolidi, Nicoletta; Sokol, Sergei Y.; Merrill, Bradley J.; Dattani, Mehul T.; Martinez-Barbera, Juan Pedro

    2016-01-01

    Aberrant embryonic development of the hypothalamus and/or pituitary gland in humans results in congenital hypopituitarism (CH). Transcription factor 7-like 1 (TCF7L1), an important regulator of the WNT/β-catenin signaling pathway, is expressed in the developing forebrain and pituitary gland, but its role during hypothalamo–pituitary (HP) axis formation or involvement in human CH remains elusive. Using a conditional genetic approach in the mouse, we first demonstrate that TCF7L1 is required in the prospective hypothalamus to maintain normal expression of the hypothalamic signals involved in the induction and subsequent expansion of Rathke’s pouch progenitors. Next, we reveal that the function of TCF7L1 during HP axis development depends exclusively on the repressing activity of TCF7L1 and does not require its interaction with β-catenin. Finally, we report the identification of two independent missense variants in human TCF7L1, p.R92P and p.R400Q, in a cohort of patients with forebrain and/or pituitary defects. We demonstrate that these variants exhibit reduced repressing activity in vitro and in vivo relative to wild-type TCF7L1. Together, our data provide support for a conserved molecular function of TCF7L1 as a transcriptional repressor during HP axis development in mammals and identify variants in this transcription factor that are likely to contribute to the etiology of CH. PMID:26764381

  5. Automated Method for Estimating Nutation Time Constant Model Parameters for Spacecraft Spinning on Axis

    Science.gov (United States)

    2008-01-01

    Calculating an accurate nutation time constant (NTC), or nutation rate of growth, for a spinning upper stage is important for ensuring mission success. Spacecraft nutation, or wobble, is caused by energy dissipation anywhere in the system. Propellant slosh in the spacecraft fuel tanks is the primary source for this dissipation and, if it is in a state of resonance, the NTC can become short enough to violate mission constraints. The Spinning Slosh Test Rig (SSTR) is a forced-motion spin table where fluid dynamic effects in full-scale fuel tanks can be tested in order to obtain key parameters used to calculate the NTC. We accomplish this by independently varying nutation frequency versus the spin rate and measuring force and torque responses on the tank. This method was used to predict parameters for the Genesis, Contour, and Stereo missions, whose tanks were mounted outboard from the spin axis. These parameters are incorporated into a mathematical model that uses mechanical analogs, such as pendulums and rotors, to simulate the force and torque resonances associated with fluid slosh.

  6. Structural Optimization Design of Horizontal-Axis Wind Turbine Blades Using a Particle Swarm Optimization Algorithm and Finite Element Method

    OpenAIRE

    Pan Pan; Rongrong Gu; Jie Zhu; Xin Cai

    2012-01-01

    This paper presents an optimization method for the structural design of horizontal-axis wind turbine (HAWT) blades based on the particle swarm optimization algorithm (PSO) combined with the finite element method (FEM). The main goal is to create an optimization tool and to demonstrate the potential improvements that could be brought to the structural design of HAWT blades. A multi-criteria constrained optimization design model pursued with respect to minimum mass of the blade is developed. Th...

  7. A New Method for Horizontal Axis Wind Turbine (HAWT Blade Optimization

    Directory of Open Access Journals (Sweden)

    Mohammadreza Mohammadi

    2016-02-01

    Full Text Available Iran has a great potential for wind energy. This paper introduces optimization of 7 wind turbine blades for small and medium scales in a determined wind condition of Zabol site, Iran, where the average wind speed is considered 7 m /s. Considered wind turbines are 3 bladed and radius of 7 case study turbine blades are 4.5 m, 6.5 m, 8 m, 9 m, 10 m, 15.5 m and 20 m. As the first step, an initial design is performed using one airfoil (NACA 63-215 across the blade. In the next step, every blade is divided into three sections, while the 20 % of first part of the blade is considered as root, the 5% of last the part is considered as tip and the rest of the blade as mid part. Providing necessary input data, suitable airfoils for wind turbines including 43 airfoils are extracted and their experimental data are entered in optimization process. Three variables in this optimization problem would be airfoil type, attack angle and chord, where the objective function is maximum output torque. A MATLAB code was written for design and optimization of the blade, which was validated with a previous experimental work. In addition, a comparison was made to show the effect of optimization with two variables (airfoil type and attack angle versus optimization with three variables (airfoil type, attack angle and chord on output torque increase. Results of this research shows a dramatic increase in comparison to initial designed blade with one airfoil where two variable optimization causes 7.7% to 22.27 % enhancement and three variable optimization causes 17.91% up to 24.48% rise in output torque .Article History: Received Oct 15, 2015; Received in revised form January 2, 2016; Accepted January 14, 2016; Available online How to Cite This Article: Mohammadi, M., Mohammadi, A. and Farahat, S. (2016 A New Method for Horizontal Axis Wind Turbine (HAWT Blade Optimization. Int. Journal of Renewable Energy Development, 5(1,1-8. http://dx.doi.org/10.14710/ijred.5.1.1-8

  8. A novel path generation method of onsite 5-axis surface inspection using the dual-cubic NURBS representation

    Science.gov (United States)

    Li, Wen-long; Wang, Gang; Zhang, Gang; Pang, Chang-tao; Yin, Zhou-pin

    2016-09-01

    Onsite surface inspection with a touch probe or a laser scanner is a promising technique for efficiently evaluating surface profile error. The existing work of 5-axis inspection path generation bears a serious drawback, however, as there is a drastic orientation change of the inspection axis. Such a sudden change may exceed the stringent physical limit on the speed and acceleration of the rotary motions of the machine tool. In this paper, we propose a novel path generation method for onsite 5-axis surface inspection. The accessibility cones are defined and used to generate alternative interference-free inspection directions. Then, the control points are optimally calculated to obtain the dual-cubic non-Uniform rational B-splines (NURBS) curves, which respectively determine the path points and the axis vectors in an inspection path. The generated inspection path is smooth and non-interference, which deals with the ‘mutation and shake’ problems and guarantees a stable speed and acceleration of machine tool rotary motions. Its feasibility and validity is verified by the onsite inspection experiments of impeller blade.

  9. The insulin-like growth factor axis and collagen turnover during prednisolone treatment

    DEFF Research Database (Denmark)

    Wolthers, O D; Juul, A; Hansen, M;

    1994-01-01

    Serum concentrations of insulin-like growth factor I (IGF-I) and insulin-like growth factor binding protein 3 (IGFBP-3), the carboxyterminal propeptide of type I collagen (PICP), the carboxyterminal pyridinoline crosslinked telopeptide of type I collagen (ICTP), and the aminoterminal propeptide....../l during the 2.5 and 5.0 mg prednisolone periods respectively. Short term treatment with low daily doses of prednisolone is associated with suppression of serum markers of type I and III collagen turnover in children with asthma. Intermediate and long term effects remain to be studied....

  10. Impaired genome maintenance suppresses the growth hormone--insulin-like growth factor 1 axis in mice with Cockayne syndrome.

    Directory of Open Access Journals (Sweden)

    Ingrid van der Pluijm

    2007-01-01

    Full Text Available Cockayne syndrome (CS is a photosensitive, DNA repair disorder associated with progeria that is caused by a defect in the transcription-coupled repair subpathway of nucleotide excision repair (NER. Here, complete inactivation of NER in Csb(m/m/Xpa(-/- mutants causes a phenotype that reliably mimics the human progeroid CS syndrome. Newborn Csb(m/m/Xpa(-/- mice display attenuated growth, progressive neurological dysfunction, retinal degeneration, cachexia, kyphosis, and die before weaning. Mouse liver transcriptome analysis and several physiological endpoints revealed systemic suppression of the growth hormone/insulin-like growth factor 1 (GH/IGF1 somatotroph axis and oxidative metabolism, increased antioxidant responses, and hypoglycemia together with hepatic glycogen and fat accumulation. Broad genome-wide parallels between Csb(m/m/Xpa(-/- and naturally aged mouse liver transcriptomes suggested that these changes are intrinsic to natural ageing and the DNA repair-deficient mice. Importantly, wild-type mice exposed to a low dose of chronic genotoxic stress recapitulated this response, thereby pointing to a novel link between genome instability and the age-related decline of the somatotroph axis.

  11. Microglial priming through the lung-brain axis: the role of air pollution-induced circulating factors.

    Science.gov (United States)

    Mumaw, Christen L; Levesque, Shannon; McGraw, Constance; Robertson, Sarah; Lucas, Selita; Stafflinger, Jillian E; Campen, Matthew J; Hall, Pamela; Norenberg, Jeffrey P; Anderson, Tamara; Lund, Amie K; McDonald, Jacob D; Ottens, Andrew K; Block, Michelle L

    2016-05-01

    Air pollution is implicated in neurodegenerative disease risk and progression and in microglial activation, but the mechanisms are unknown. In this study, microglia remained activated 24 h after ozone (O3) exposure in rats, suggesting a persistent signal from lung to brain. Ex vivo analysis of serum from O3-treated rats revealed an augmented microglial proinflammatory response and β-amyloid 42 (Aβ42) neurotoxicity independent of traditional circulating cytokines, where macrophage-1 antigen-mediated microglia proinflammatory priming. Aged mice exhibited reduced pulmonary immune profiles and the most pronounced neuroinflammation and microglial activation in response to mixed vehicle emissions. Consistent with this premise, cluster of differentiation 36 (CD36)(-/-) mice exhibited impaired pulmonary immune responses concurrent with augmented neuroinflammation and microglial activation in response to O3 Further, aging glia were more sensitive to the proinflammatory effects of O3 serum. Together, these findings outline the lung-brain axis, where air pollutant exposures result in circulating, cytokine-independent signals present in serum that elevate the brain proinflammatory milieu, which is linked to the pulmonary response and is further augmented with age.-Mumaw, C. L., Levesque, S., McGraw, C., Robertson, S., Lucas, S., Stafflinger, J. E., Campen, M. J., Hall, P., Norenberg, J. P., Anderson, T., Lund, A. K., McDonald, J. D., Ottens, A. K., Block, M. L. Microglial priming through the lung-brain axis: the role of air pollution-induced circulating factors. PMID:26864854

  12. Hypoxia-inducible factor-1 α/platelet derived growth factor axis in HIV-associated pulmonary vascular remodeling

    Directory of Open Access Journals (Sweden)

    Bartolome Sonja

    2011-08-01

    Full Text Available Abstract Background Human immunodeficiency virus (HIV infected patients are at increased risk for the development of pulmonary arterial hypertension (PAH. Recent reports have demonstrated that HIV associated viral proteins induce reactive oxygen species (ROS with resultant endothelial cell dysfunction and related vascular injury. In this study, we explored the impact of HIV protein induced oxidative stress on production of hypoxia inducible factor (HIF-1α and platelet-derived growth factor (PDGF, critical mediators implicated in the pathogenesis of HIV-PAH. Methods The lungs from 4-5 months old HIV-1 transgenic (Tg rats were assessed for the presence of pulmonary vascular remodeling and HIF-1α/PDGF-BB expression in comparison with wild type controls. Human primary pulmonary arterial endothelial cells (HPAEC were treated with HIV-associated proteins in the presence or absence of pretreatment with antioxidants, for 24 hrs followed by estimation of ROS levels and western blot analysis of HIF-1α or PDGF-BB. Results HIV-Tg rats, a model with marked viral protein induced vascular oxidative stress in the absence of active HIV-1 replication demonstrated significant medial thickening of pulmonary vessels and increased right ventricular mass compared to wild-type controls, with increased expression of HIF-1α and PDGF-BB in HIV-Tg rats. The up-regulation of both HIF-1α and PDGF-B chain mRNA in each HIV-Tg rat was directly correlated with an increase in right ventricular/left ventricular+septum ratio. Supporting our in-vivo findings, HPAECs treated with HIV-proteins: Tat and gp120, demonstrated increased ROS and parallel increase of PDGF-BB expression with the maximum induction observed on treatment with R5 type gp-120CM. Pre-treatment of endothelial cells with antioxidants or transfection of cells with HIF-1α small interfering RNA resulted in abrogation of gp-120CM mediated induction of PDGF-BB, therefore, confirming that ROS generation and

  13. The insulin-like growth factor 1 axis in prognosis and treatment of breast cancer

    NARCIS (Netherlands)

    Hartog, Hermien

    2014-01-01

    Insulin-like growth factor-1 receptor (IGF-1R) is a tyrosine kinase receptor mediating cell growth and survival. IGF-1R signaling has been implicated in malignant behavior of tumors and drugs targeting the IGF-1R as anticancer treatment have been developed. We aimed to determine clinical indicators

  14. Confirmatory Factor Analysis of the Psychopathy Checklist: Screening Version in Offenders With Axis I Disorders

    Science.gov (United States)

    Hill, Christie D.; Neumann, Craig S.; Rogers, Richard

    2004-01-01

    One hundred forty-nine inpatients within a maximum security psychiatric facility were assessed with the Psychopathy Checklist: Screening Version (PCL:SV; S. D. Hart, D. N. Cox, & R. D. Hare, 1995). Within the total sample, 68% had a psychotic disorder and 30% met criteria for psychopathy. Using confirmatory factor analysis, the authors tested the…

  15. On the factorization method in quantum mechanics

    CERN Document Server

    Rosas-Ortiz, J O

    1998-01-01

    New exactly solvable problems have already been studied by using a modification of the factorization method introduced by Mielnik. We review this method and its connection with the traditional factorization method. The survey includes the discussion on a generalization of the factorization energies used in the traditional Infeld and Hull method.

  16. A novel method for defining the Greyhound talocrural joint axis of rotation for hinged transarticular external skeletal fixation.

    Science.gov (United States)

    Colborne, G R; Hadley, N R; Wallace, A M

    2013-01-01

    In order to apply hinged transarticular external skeletal fixation for stabilization of the injured canine tarsal joint, knowledge of the three-dimensional (3D) location and orientation of the transverse axis is necessary. This method of immobilization may be used as a primary or adjunctive method of stabilisation for a large number of traumatic conditions. Using pin-mounted markers in the cadaveric Greyhound crus and talus, a closed-form solution of absolute orientation was used to identify, on radiographs, the lateral and medial locations of the transverse axis by tracking the 3D excursions of the markers during flexion and extension. A line was drawn across the dorsal aspect of the calcaneus from the most dorsal point on the distal articular surface(proximal intertarsal joint: PIJ) to the most dorsal point on its proximal articulation with the body of the talus, and the location of the centre of rotation was expressed in terms of the length of that line. In seven Greyhound tarsal joints, the medial end of the axis was located 73 ± 10% proximal to the PIJ and 11 ± 7% dorsal to the line. The lateral end was 73 ± 9% proximal tothe PIJ and -2 ± 3% plantar to the line. PMID:23612749

  17. Hepatoma-derived growth factor/nucleolin axis as a novel oncogenic pathway in liver carcinogenesis.

    Science.gov (United States)

    Chen, San-Cher; Hu, Tsung-Hui; Huang, Chao-Cheng; Kung, Mei-Lang; Chu, Tian-Huei; Yi, Li-Na; Huang, Shih-Tsung; Chan, Hoi-Hung; Chuang, Jiin-Haur; Liu, Li-Feng; Wu, Han-Chung; Wu, Deng-Chyang; Chang, Min-Chi; Tai, Ming-Hong

    2015-06-30

    Hepatoma-derived growth factor (HDGF) overexpression is involved in liver fibrosis and carcinogenesis. However, the receptor(s) and signaling for HDGF remain unclear. By using affinity chromatography and proteomic techniques, nucleolin (NCL) was identified and validated as a HDGF-interacting membrane protein in hepatoma cells. Exogenous HDGF elicited the membrane NCL accumulation within 0.5 hour by protein stabilization and transcriptional NCL upregulation within 24 hours. Blockade of surface NCL by antibodies neutralization potently suppressed HDGF uptake and HDGF-stimulated phosphatidylinositol 3-kinase (PI3K)/Akt signaling in hepatoma cells. By using rescectd hepatocellular carcinoma (HCC) tissues, immunohistochemical analysis revealed NCL overexpression was correlated with tumour grades, vascular invasion, serum alpha-fetoprotein levels and the poor survival in HCC patients. Multivariate analysis showed NCL was an independent prognostic factor for survival outcome of HCC patients after surgery. To delineate the role of NCL in liver carcinogenesis, ectopic NCL overexpression promoted the oncogenic behaviours and induced PI3K/Akt activation in hepatoma cells. Conversely, NCL knockdown by RNA interference attenuated the oncogenic behaviours and PI3K/Akt signaling, which could be partially rescued by exogenous HDGF supply. In summary, this study provides the first evidence that surface NCL transmits the oncogenic signaling of HDGF and facilitates a novel diagnostic and therapeutic target for HCC. PMID:25938538

  18. A New Factorization Method to Factorize RSA Public Key Encryption

    Directory of Open Access Journals (Sweden)

    Bhagvant Ram Ambedkar

    2011-11-01

    Full Text Available The security of public key encryption such as RSA scheme relied on the integer factoring problem. The security of RSA algorithm is based on positive integer N, because each transmitting node generates pair of keys such as public and private. Encryption and decryption of any message depends on N. Where, N is the product of two prime numbers and pair of key generation is dependent on these prime numbers. The factorization of N is very intricate. In this paper a New Factorization method is proposed to obtain the factor of positive integer N. The proposed work focuses on factorization of all trivial and nontrivial integer numbers and requires fewer steps for factorization process of RSA modulus N. The New Factorization method is based on Pollard rho factorization method. Experimental results shown that factorization speed is fast as compare existing methods.

  19. Gut Microbiome and Infant Health: Brain-Gut-Microbiota Axis and Host Genetic Factors

    Science.gov (United States)

    Cong, Xiaomei; Xu, Wanli; Romisher, Rachael; Poveda, Samantha; Forte, Shaina; Starkweather, Angela; Henderson, Wendy A.

    2016-01-01

    The development of the neonatal gut microbiome is influenced by multiple factors, such as delivery mode, feeding, medication use, hospital environment, early life stress, and genetics. The dysbiosis of gut microbiota persists during infancy, especially in high-risk preterm infants who experience lengthy stays in the Neonatal intensive care unit (NICU). Infant microbiome evolutionary trajectory is essentially parallel with the host (infant) neurodevelopmental process and growth. The role of the gut microbiome, the brain-gut signaling system, and its interaction with the host genetics have been shown to be related to both short and long term infant health and bio-behavioral development. The investigation of potential dysbiosis patterns in early childhood is still lacking and few studies have addressed this host-microbiome co-developmental process. Further research spanning a variety of fields of study is needed to focus on the mechanisms of brain-gut-microbiota signaling system and the dynamic host-microbial interaction in the regulation of health, stress and development in human newborns.

  20. Human Factors of Formal Methods

    OpenAIRE

    Spichkova, Maria

    2014-01-01

    This paper provides a brief introduction to the work that aims to apply the achievements within the area of engineering psychology to the area of formal methods, focusing on the specification phase of a system development process.

  1. Comparison of three formal methods used to estimate the functional axis of rotation: an extensive in-vivo analysis performed on the knee joint.

    Science.gov (United States)

    Colle, Francesca; Lopomo, Nicola; Visani, Andrea; Zaffagnini, Stefano; Marcacci, Maurilio

    2016-01-01

    Estimating the main axis of rotation (AoR) of a human joint represents an important issue in biomechanics. This study compared three formal methods used to estimate functional AoR, namely a cylindrical fitting method, a mean helical axis transformation, and a symmetrical axis approach. These methods were tested on 106 subjects undergoing navigated total knee arthroplasty. AoR orientation in 3D and in the frontal and coronal planes provided by each method was compared to the transepicondylar axis direction. Although all the methods resulted effective, significant differences were identified among them, relatively to the orientation in 3D and in the frontal plane projection. This was probably due to the presence of secondary rotations during the first degrees of knee flexion.

  2. The Hepatocyte Growth Factor (HGF)/Met Axis: A Neglected Target in the Treatment of Chronic Myeloproliferative Neoplasms?

    International Nuclear Information System (INIS)

    Met is the receptor of hepatocyte growth factor (HGF), a cytoprotective cytokine. Disturbing the equilibrium between Met and its ligand may lead to inappropriate cell survival, accumulation of genetic abnormalities and eventually, malignancy. Abnormal activation of the HGF/Met axis is established in solid tumours and in chronic haematological malignancies, including myeloma, acute myeloid leukaemia, chronic myelogenous leukaemia (CML), and myeloproliferative neoplasms (MPNs). The molecular mechanisms potentially responsible for the abnormal activation of HGF/Met pathways are described and discussed. Importantly, inCML and in MPNs, the production of HGF is independent of Bcr-Abl and JAK2V617F, the main molecular markers of these diseases. In vitro studies showed that blocking HGF/Met function with neutralizing antibodies or Met inhibitors significantly impairs the growth of JAK2V617F-mutated cells. With personalised medicine and curative treatment in view, blocking activation of HGF/Met could be a useful addition in the treatment of CML and MPNs for those patients with high HGF/MET expression not controlled by current treatments (Bcr-Abl inhibitors in CML; phlebotomy, hydroxurea, JAK inhibitors in MPNs)

  3. The Hepatocyte Growth Factor (HGF)/Met Axis: A Neglected Target in the Treatment of Chronic Myeloproliferative Neoplasms?

    Energy Technology Data Exchange (ETDEWEB)

    Boissinot, Marjorie [Translational Neuro-Oncology Group, Leeds Institute of Cancer and Pathology, University of Leeds, Level 5 Wellcome Trust Brenner Building, St James’s Hospital, Leeds LS9 7TF (United Kingdom); Vilaine, Mathias [Institute of Research on Cancer and Aging (IRCAN), CNRS-Inserm-UNS UMR 7284, U 1081, Centre A. Lacassagne, 33 Avenue Valombrose, Nice 06189 (France); Hermouet, Sylvie, E-mail: sylvie.hermouet@univ-nantes.fr [Centre Hospitalier Universitaire (CHU), Place Alexis Ricordeau, Nantes 44093 (France); Inserm UMR892, Centre de Recherche en Cancérologie Nantes-Angers, Institut de Recherche en Santé, Université de Nantes, 8 quai Moncousu, Nantes cedex 44007 (France)

    2014-08-12

    Met is the receptor of hepatocyte growth factor (HGF), a cytoprotective cytokine. Disturbing the equilibrium between Met and its ligand may lead to inappropriate cell survival, accumulation of genetic abnormalities and eventually, malignancy. Abnormal activation of the HGF/Met axis is established in solid tumours and in chronic haematological malignancies, including myeloma, acute myeloid leukaemia, chronic myelogenous leukaemia (CML), and myeloproliferative neoplasms (MPNs). The molecular mechanisms potentially responsible for the abnormal activation of HGF/Met pathways are described and discussed. Importantly, inCML and in MPNs, the production of HGF is independent of Bcr-Abl and JAK2V617F, the main molecular markers of these diseases. In vitro studies showed that blocking HGF/Met function with neutralizing antibodies or Met inhibitors significantly impairs the growth of JAK2V617F-mutated cells. With personalised medicine and curative treatment in view, blocking activation of HGF/Met could be a useful addition in the treatment of CML and MPNs for those patients with high HGF/MET expression not controlled by current treatments (Bcr-Abl inhibitors in CML; phlebotomy, hydroxurea, JAK inhibitors in MPNs)

  4. The Hepatocyte Growth Factor (HGF/Met Axis: A Neglected Target in the Treatment of Chronic Myeloproliferative Neoplasms?

    Directory of Open Access Journals (Sweden)

    Marjorie Boissinot

    2014-08-01

    Full Text Available Met is the receptor of hepatocyte growth factor (HGF, a cytoprotective cytokine. Disturbing the equilibrium between Met and its ligand may lead to inappropriate cell survival, accumulation of genetic abnormalities and eventually, malignancy. Abnormal activation of the HGF/Met axis is established in solid tumours and in chronic haematological malignancies, including myeloma, acute myeloid leukaemia, chronic myelogenous leukaemia (CML, and myeloproliferative neoplasms (MPNs. The molecular mechanisms potentially responsible for the abnormal activation of HGF/Met pathways are described and discussed. Importantly, inCML and in MPNs, the production of HGF is independent of Bcr-Abl and JAK2V617F, the main molecular markers of these diseases. In vitro studies showed that blocking HGF/Met function with neutralizing antibodies or Met inhibitors significantly impairs the growth of JAK2V617F-mutated cells. With personalised medicine and curative treatment in view, blocking activation of HGF/Met could be a useful addition in the treatment of CML and MPNs for those patients with high HGF/MET expression not controlled by current treatments (Bcr-Abl inhibitors in CML; phlebotomy, hydroxurea, JAK inhibitors in MPNs.

  5. Regulation of Connective Tissue Growth Factor and Cardiac Fibrosis by an SRF/MicroRNA-133a Axis.

    Directory of Open Access Journals (Sweden)

    Aude Angelini

    Full Text Available Myocardial fibrosis contributes to the remodeling of heart and the loss of cardiac function leading to heart failure. SRF is a transcription factor implicated in the regulation of a large variety of genes involved in cardiac structure and function. To investigate the impact of an SRF overexpression in heart, we developed a new cardiac-specific and tamoxifen-inducible SRF overexpression mouse model by the Cre/loxP strategy. Here, we report that a high level overexpression of SRF leads to severe modifications of cardiac cytoarchitecture affecting the balance between cardiomyocytes and cardiac fibroblasts and also a profound alteration of cardiac gene expression program. The drastic development of fibrosis was characterized by intense sirius red staining and associated with an increased expression of genes encoding extracellular matrix proteins such as fibronectin, procollagen type 1α1 and type 3α1 and especially connective tissue growth factor (CTGF. Furthermore miR-133a, one of the most predominant cardiac miRNAs, is strongly downregulated when SRF is overexpressed. By comparison a low level overexpression of SRF has minor impact on these different processes. Investigation with miR-133a, antimiR-133a and AdSRF-VP16 experiments in H9c2 cardiac cells demonstrated that: 1-miR-133a acts as a repressor of SRF and CTGF expression; 2-a simultaneous overexpression of SRF by AdSRF-VP16 and inhibition of miR-133a by a specific antimiR increase CTGF expression; 3-miR-133a overexpression can block the upregulation of CTGF induced by AdSRF-VP16. Taken together, these findings reveal a key role of the SRF/CTGF/miR-133a axis in the regulation of cardiac fibrosis.

  6. Physical parameter identification method based on modal analysis for two-axis on-road vehicles: Theory and simulation

    Science.gov (United States)

    Zheng, Minyi; Zhang, Bangji; Zhang, Jie; Zhang, Nong

    2016-07-01

    Physical parameters are very important for vehicle dynamic modeling and analysis. However, most of physical parameter identification methods are assuming some physical parameters of vehicle are known, and the other unknown parameters can be identified. In order to identify physical parameters of vehicle in the case that all physical parameters are unknown, a methodology based on the State Variable Method(SVM) for physical parameter identification of two-axis on-road vehicle is presented. The modal parameters of the vehicle are identified by the SVM, furthermore, the physical parameters of the vehicle are estimated by least squares method. In numerical simulations, physical parameters of Ford Granada are chosen as parameters of vehicle model, and half-sine bump function is chosen to simulate tire stimulated by impulse excitation. The first numerical simulation shows that the present method can identify all of the physical parameters and the largest absolute value of percentage error of the identified physical parameter is 0.205%; and the effect of the errors of additional mass, structural parameter and measurement noise are discussed in the following simulations, the results shows that when signal contains 30 dB noise, the largest absolute value of percentage error of the identification is 3.78%. These simulations verify that the presented method is effective and accurate for physical parameter identification of two-axis on-road vehicles. The proposed methodology can identify all physical parameters of 7-DOF vehicle model by using free-decay responses of vehicle without need to assume some physical parameters are known.

  7. Methods to assess the effects of environmental chemicals on the brain-pituitary-gonad axis of the reproductive system

    Energy Technology Data Exchange (ETDEWEB)

    Magliulo-Cepriano, L.; Schreibman, M.P.

    1999-07-01

    In all vertebrates, the neuroendocrine system serves as the primary and essential link between the external and internal environments and a multitude of physiological systems, including the reproductive system. In response to changes in the environment and fluctuations in levels of circulating humoral agents, the neuroendocrine system is able to reverse, maintain or advance physiological events. Endocrine disrupting compounds are believed to wreak havoc on reproduction and development by interfering in the normal flow of information along the brain-pituitary-gonad axis. While the final effects of these compounds may be easily determined in a number of species, utilization of non-traditional research animals, such as some fishes in which the pattern of information flow along the brain-pituitary-gonad axis has been meticulously detailed and documented, will provide excellent and novel means of elucidating not only the final effects but the cytological, histological and systemic mechanisms of action of these endocrine disruptors. This report presents methods of assessing the effects of endocrine disrupting compounds on a variety of physiological and morphological parameters in fishes.

  8. An Aerodynamic Method for the Preliminary Design of Horizontal Axis Wind Turbines

    Directory of Open Access Journals (Sweden)

    X. Munduate

    2000-01-01

    Full Text Available The present paper describes a method developed to assist in the preliminary aerodynamic design of wind turbines by identifying regions of the rotor disk which are dominated by unsteady and/or three-dimensional effects. The technique is based on a blade element/momentum predictor that has been extended to consider yawed flow and tower shadow effects. In addition, the method tracks temporal changes in blade incidence to identify regions of the rotor disk which are susceptible to dynamic stall. It also monitors and assesses the severity of three-dimensional stall delay and the extent to which this interacts with the regions of unsteadiness. In the paper the capability of the method will be demonstrated by application to the specific test case of the U. S. National Renewable Energy Laboratories (NREL Combined Experiment turbine.

  9. An unsteady vortex lattice method model of a horizontal axis wind turbine operating in an upstream rotor wake

    Science.gov (United States)

    Hankin, D.; Graham, J. M. R.

    2014-12-01

    An unsteady formulation of the vortex lattice method, VLM, is presented that uses a force- free representation of the wake behind a horizontal axis wind turbine, HAWT, to calculate the aerodynamic loading on a turbine operating in the wake of an upstream rotor. A Cartesian velocity grid is superimposed over the computational domain to facilitate the representation of the atmospheric turbulence surrounding the turbine and wind shear. The wake of an upstream rotor is modelled using two methods: a mean velocity deficit with superimposed turbulence, based on experimental observations, and a purely numeric periodic boundary condition. Both methods are treated as frozen and propagated with the velocity grid. Measurements of the mean thrust and blade root bending moment on a three bladed horizontal axis rotor modelling a 5 MW HAWT at 1:250 scale were carried out in a wind tunnel. Comparisons are made between operation in uniform flow and in the wake of a similarly loaded rotor approximately 6.5 diameters upstream. The measurements were used to validate the output from the VLM simulations, assuming a completely rigid rotor. The trends in the simulation thrust predictions are found to compare well with the uniform flow case, except at low tip speed ratios where there are losses due to stall which are yet to be included in the model. The simple wake model predicts the mean deficit, whilst the periodic boundary condition captures more of the frequency content of the loading in an upstream wake. However, all the thrust loads are over-predicted. The simulation results severely overestimate the bending moment, which needs addressing. However, the reduction in bending due to the simple wake model is found to reflect the experimental data reasonably well.

  10. Method and apparatus for calibrating multi-axis load cells in a dexterous robot

    Science.gov (United States)

    Wampler, II, Charles W. (Inventor); Platt, Jr., Robert J. (Inventor)

    2012-01-01

    A robotic system includes a dexterous robot having robotic joints, angle sensors adapted for measuring joint angles at a corresponding one of the joints, load cells for measuring a set of strain values imparted to a corresponding one of the load cells during a predetermined pose of the robot, and a host machine. The host machine is electrically connected to the load cells and angle sensors, and receives the joint angle values and strain values during the predetermined pose. The robot presses together mating pairs of load cells to form the poses. The host machine executes an algorithm to process the joint angles and strain values, and from the set of all calibration matrices that minimize error in force balance equations, selects the set of calibration matrices that is closest in a value to a pre-specified value. A method for calibrating the load cells via the algorithm is also provided.

  11. Structural Optimization Design of Horizontal-Axis Wind Turbine Blades Using a Particle Swarm Optimization Algorithm and Finite Element Method

    Directory of Open Access Journals (Sweden)

    Pan Pan

    2012-11-01

    Full Text Available This paper presents an optimization method for the structural design of horizontal-axis wind turbine (HAWT blades based on the particle swarm optimization algorithm (PSO combined with the finite element method (FEM. The main goal is to create an optimization tool and to demonstrate the potential improvements that could be brought to the structural design of HAWT blades. A multi-criteria constrained optimization design model pursued with respect to minimum mass of the blade is developed. The number and the location of layers in the spar cap and the positions of the shear webs are employed as the design variables, while the strain limit, blade/tower clearance limit and vibration limit are taken into account as the constraint conditions. The optimization of the design of a commercial 1.5 MW HAWT blade is carried out by combining the above method and design model under ultimate (extreme flap-wise load conditions. The optimization results are described and compared with the original design. It shows that the method used in this study is efficient and produces improved designs.

  12. Active stall control for large offshore horizontal axis wind turbines: a conceptual study considering different actuation methods

    NARCIS (Netherlands)

    Pereira, R.; Van Bussel, G.J.W.; Timmer, W.A.

    2014-01-01

    The increasing size of Horizontal Axis Wind Turbines and the trend to install wind farms further offshore demand more robust design options. If the pitch system could be eliminated, the availability of Horizontal Axis Wind Turbines should increase. This research investigates the use of active stall

  13. A New Factorization Method to Factorize RSA Public Key Encryption

    OpenAIRE

    Bhagvant Ram Ambedkar; Sarabjeet Singh Bedi

    2011-01-01

    The security of public key encryption such as RSA scheme relied on the integer factoring problem. The security of RSA algorithm is based on positive integer N, because each transmitting node generates pair of keys such as public and private. Encryption and decryption of any message depends on N. Where, N is the product of two prime numbers and pair of key generation is dependent on these prime numbers. The factorization of N is very intricate. In this paper a New Factorization method is propo...

  14. Normal sweat secretion despite impaired growth hormone-insulin-like growth factor-I axis in obese subjects

    DEFF Research Database (Denmark)

    Rasmussen, Michael Højby; Juul, Anders; Main, Katharina M;

    2011-01-01

    Adults with GH deficiency are known to exhibit reduced sweating. Whether sweating capacity is impacted in obese subjects with impaired GH secretion have not previously been investigated. The main objective was to investigate sweat secretion rate and the GH-IGF-I axis in obese subjects before and ...

  15. A METHOD OF DETERMINING THE COORDINATES OF THE STIFFNESS CENTER AND THE STIFFNESS PRINCIPAL AXIS OF THE VIBRATING SYSTEM WITH DAMPING

    OpenAIRE

    Dang Xuan Truong; Tran Duc Chinh

    2014-01-01

    The report presents a methodology to determine the directions of the stiffness principal axis (in this case subject to the linear displacement and forced rotation angle) of a solid object interact with the surrounding environment by resilient bearing supports. The results also show that determining the coordinates of the stiffness center in the vibrating system with damping factors is necessary in our research.

  16. The Performance Test of Three Different Horizontal Axis Wind Turbine (HAWT Blade Shapes Using Experimental and Numerical Methods

    Directory of Open Access Journals (Sweden)

    Wen-Tong Chong

    2013-06-01

    Full Text Available Three different horizontal axis wind turbine (HAWT blade geometries with the same diameter of 0.72 m using the same NACA4418 airfoil profile have been investigated both experimentally and numerically. The first is an optimum (OPT blade shape, obtained using improved blade element momentum (BEM theory. A detailed description of the blade geometry is also given. The second is an untapered and optimum twist (UOT blade with the same twist distributions as the OPT blade. The third blade is untapered and untwisted (UUT. Wind tunnel experiments were used to measure the power coefficients of these blades, and the results indicate that both the OPT and UOT blades perform with the same maximum power coefficient, Cp = 0.428, but it is located at different tip speed ratio, λ = 4.92 for the OPT blade and λ = 4.32 for the UOT blade. The UUT blade has a maximum power coefficient of Cp = 0.210 at λ = 3.86. After the tests, numerical simulations were performed using a full three-dimensional computational fluid dynamics (CFD method using the k-ω SST turbulence model. It has been found that CFD predictions reproduce the most accurate model power coefficients. The good agreement between the measured and computed power coefficients of the three models strongly suggest that accurate predictions of HAWT blade performance at full-scale conditions are also possible using the CFD method.

  17. Resolution of a triple axis spectrometer

    DEFF Research Database (Denmark)

    Nielsen, Mourits; Bjerrum Møller, Hans

    1969-01-01

    A new method for obtaining the resolution function for a triple-axis neutron spectrometer is described, involving a combination of direct measurement and analytical calculation. All factors which contribute to the finite resolution of the instrument may be taken into account, and Gaussian...

  18. Characterizing the Adaptive Optics Off-Axis Point-Spread Function. II. Methods for Use in Laser Guide Star Observations

    CERN Document Server

    Steinbring, E; MacIntosh, B A; Gavel, D; Gates, E L

    2005-01-01

    Most current astronomical adaptive optics (AO) systems rely on the availability of a bright star to measure the distortion of the incoming wavefront. Replacing the guide star with an artificial laser beacon alleviates this dependency on bright stars and therefore increases sky coverage, but it does not eliminate another serious problem for AO observations. This is the issue of PSF variation with time and field position near the guide star. In fact, because a natural guide star is still necessary for correction of the low-order phase error, characterization of laser guide star (LGS) AO PSF spatial variation is more complicated than for a natural guide star alone. We discuss six methods for characterizing LGS AO PSF variation that can potentially improve the determination of the PSF away from the laser spot, that is, off-axis. Calibration images of dense star fields are used to determine the change in PSF variation with field position. This is augmented by AO system telemetry and simple computer simulations to ...

  19. Vertical Axis Wind Turbine flows using a Vortex Particle-Mesh method: from near to very far wakes

    Science.gov (United States)

    Backaert, Stephane; Chatelain, Philippe; Winckelmans, Gregoire; Kern, Stefan; Maeder, Thierry; von Terzi, Dominic; van Rees, Wim; Koumoutsakos, Petros

    2012-11-01

    A Vortex Particle-Mesh (VPM) method with immersed lifting lines has been developed and validated. The vorticity-velocity formulation of the NS equations is treated in a hybrid way: particles handle advection while the mesh is used to evaluate the differential operators and for the fast Poisson solvers (here a Fourier-based solver which simultaneously allows for unbounded directions and inlet/outlet boundaries). Both discretizations communicate through high order interpolation. The immersed lifting lines handle the creation of vorticity from the blade elements and its early development. LES of Vertical Axis Wind Turbine (VAWT) flows are performed, with a relatively fine resolution (128 and 160 grid points per blade) and for computational domains extending up to 6 D and 14 D downstream of the rotor. The wake complex development is captured in details, from the blades to the near wake coherent vortices, to the transitional ones, to the fully developed turbulent far wake. Mean flow statistics in planes (horizontal, vertical and cross) are also presented. A case with a realistic turbulent wind inflow is also considered. The physics are more complex than for HAWT flows. Computational resources provided by a PRACE award.

  20. A semi-dominant mutation in the general splicing factor SF3a66 causes anterior-posterior axis reversal in one-cell stage C. elegans embryos.

    Directory of Open Access Journals (Sweden)

    Mohammad R Keikhaee

    Full Text Available Establishment of anterior-posterior polarity in one-cell stage Caenorhabditis elegans embryos depends in part on astral microtubules. As the zygote enters mitosis, these microtubules promote the establishment of a posterior pole by binding to and protecting a cytoplasmic pool of the posterior polarity protein PAR-2 from phosphorylation by the cortically localized anterior polarity protein PKC-3. Prior to activation of the sperm aster, the oocyte Meiosis I and II spindles assemble and function, usually at the future anterior pole, but these meiotic spindle microtubules fail to establish posterior polarity through PAR-2. Here we show that a semi-dominant mutation in the general splicing factor SF3a66 can lead to a reversed axis of AP polarity that depends on PAR-2 and possibly on close proximity of oocyte meiotic spindles with the cell cortex. One possible explanation is that reduced levels of PKC-3, due to a general splicing defect, can result in axis reversal due to a failure to prevent oocyte meiotic spindle microtubules from interfering with AP axis formation.

  1. Synthesizing regression results: a factored likelihood method.

    Science.gov (United States)

    Wu, Meng-Jia; Becker, Betsy Jane

    2013-06-01

    Regression methods are widely used by researchers in many fields, yet methods for synthesizing regression results are scarce. This study proposes using a factored likelihood method, originally developed to handle missing data, to appropriately synthesize regression models involving different predictors. This method uses the correlations reported in the regression studies to calculate synthesized standardized slopes. It uses available correlations to estimate missing ones through a series of regressions, allowing us to synthesize correlations among variables as if each included study contained all the same variables. Great accuracy and stability of this method under fixed-effects models were found through Monte Carlo simulation. An example was provided to demonstrate the steps for calculating the synthesized slopes through sweep operators. By rearranging the predictors in the included regression models or omitting a relatively small number of correlations from those models, we can easily apply the factored likelihood method to many situations involving synthesis of linear models. Limitations and other possible methods for synthesizing more complicated models are discussed. Copyright © 2012 John Wiley & Sons, Ltd. PMID:26053653

  2. Method and phantom to study combined effects of in-plane (x,y) and z-axis resolution for 3D CT imaging.

    Science.gov (United States)

    Goodenough, David; Levy, Josh; Kristinsson, Smari; Fredriksson, Jesper; Olafsdottir, Hildur; Healy, Austin

    2016-01-01

    pattern amenable to analytic analysis using Fourier Transform methods, and is believed to offer an image quality test closer to the diagnostic task where the 2D image has the hidden third (z) axis effects. PMID:27685130

  3. Method and phantom to study combined effects of in-plane (x,y) and z-axis resolution for 3D CT imaging.

    Science.gov (United States)

    Goodenough, David; Levy, Josh; Kristinsson, Smari; Fredriksson, Jesper; Olafsdottir, Hildur; Healy, Austin

    2016-09-08

    pattern amenable to analytic analysis using Fourier Transform methods, and is believed to offer an image quality test closer to the diagnostic task where the 2D image has the hidden third (z) axis effects.

  4. Effects of sericin on the testicular growth hormone/insulin-like growth factor-1 axis in a rat model of type 2 diabetes

    OpenAIRE

    Song, Cheng-Jun; Yang, Zhen-Jun; Tang, Qi-Feng; Chen, Zhi-Hong

    2015-01-01

    This study investigated the effects of sericin on the testicular growth hormone (GH)/insulin-like growth factor-1 (IGF-1) axis in rats with type 2 diabetes mellitus. Forty rats were randomly assigned to normal control, type 2 diabetes mellitus, sericin and metformin treated groups. Type 2 diabetes was established by repeated intraperitoneal injection of streptozotocin, and identified by blood glucose ≥16.7 mmol/L at 1 week. The diabetic rats were given no other treatment, these rats in the se...

  5. A METHOD OF DETERMINING THE COORDINATES OF THE STIFFNESS CENTER AND THE STIFFNESS PRINCIPAL AXIS OF THE VIBRATING SYSTEM WITH DAMPING

    Directory of Open Access Journals (Sweden)

    Dang Xuan Truong

    2014-12-01

    Full Text Available The report presents a methodology to determine the directions of the stiffness principal axis (in this case subject to the linear displacement and forced rotation angle of a solid object interact with the surrounding environment by resilient bearing supports. The results also show that determining the coordinates of the stiffness center in the vibrating system with damping factors is necessary in our research.

  6. Review of human factors guidelines and methods

    International Nuclear Information System (INIS)

    The review examines the use of human factors guidelines and methods in high technology applications, with emphasis on application to the nuclear industry. An extensive literature review was carried out identifying over 250 applicable documents, with 30 more documents identified during interviews with experts in human factors. Surveys were sent to 15 experts, of which 11 responded. The survey results indicated guidelines used and why these were favoured. Thirty-three of the most applicable guideline documents were described in detailed annotated bibliographies. A bibliographic list containing over 280 references was prepared. Thirty guideline documents were rated for their completeness, validity, applicability and practicality. The experts survey indicated the use of specific techniques. Ten human factors methods of analysis were described in general summaries, including procedures, applications, and specific techniques. Detailed descriptions of the techniques were prepared and each technique rated for applicability and practicality. Recommendations for further study of areas of importance to human factors in the nuclear field in Canada are given. (author). 8 tabs., 2 figs

  7. A rapid method to derive horizontal distributions of trace gases and aerosols near the surface using multi-axis differential optical absorption spectroscopy

    Directory of Open Access Journals (Sweden)

    Y. Wang

    2013-09-01

    Full Text Available We apply a novel experimental procedure for the rapid measurement of the average volume mixing ratios (VMRs and horizontal distributions of trace gases such as NO2, SO2, and HCHO in the boundary layer, which was recently suggested by Sinreich et al. (2013. The method is based on two-dimensional scanning multi-axis differential optical absorption spectroscopy (MAX-DOAS. It makes use of two facts (Sinreich et al. 2013: First, the light path for observations at 1° elevation angle traverses mainly air masses located close to the ground (typically 4. Thus, the average value of the trace gas VMR in the atmospheric layer between the surface and the altitude, for which this observation was sensitive, can be calculated. Compared to the originally proposed method, we introduce several important modifications and improvements: We apply the method only to measurements at 1° elevation angles, for which the uncertainties are especially small. Using only 1 elevation angle also allows an increased temporal resolution. We apply correction factors (and their uncertainties as function of the simultaneously modelled O4 absorption. In this way the correction factors can be directly determined according to the measured O4 dAMF. Finally, the method is extended to trace gases analysed at other wavelengths and also to the retrieval of the aerosol extinction. Depending on the atmospheric visibility, the typical uncertainty of the results ranges from about 15 to 30%. We apply the rapid method to observations of a newly developed ground-based multifunctional passive differential optical absorption spectroscopy (GM-DOAS instrument in the north-west outskirt near Hefei City in China. We report NO2, SO2, and HCHO VMRs and aerosol extinction for four azimuth angles and compare these results with those from simultaneous long-path DOAS observations. Good agreement is found (squares of the correlation coefficients for NO2, SO2, and HCHO were 0.92, 0.84, and 0.59, respectively

  8. Growth and the Growth Hormone-Insulin Like Growth Factor 1 Axis in Children With Chronic Inflammation: Current Evidence, Gaps in Knowledge, and Future Directions.

    Science.gov (United States)

    Wong, S C; Dobie, R; Altowati, M A; Werther, G A; Farquharson, C; Ahmed, S F

    2016-02-01

    Growth failure is frequently encountered in children with chronic inflammatory conditions like juvenile idiopathic arthritis, inflammatory bowel disease, and cystic fibrosis. Delayed puberty and attenuated pubertal growth spurt are often seen during adolescence. The underlying inflammatory state mediated by proinflammatory cytokines, prolonged use of glucocorticoid, and suboptimal nutrition contribute to growth failure and pubertal abnormalities. These factors can impair growth by their effects on the GH-IGF axis and also directly at the level of the growth plate via alterations in chondrogenesis and local growth factor signaling. Recent studies on the impact of cytokines and glucocorticoid on the growth plate further advanced our understanding of growth failure in chronic disease and provided a biological rationale of growth promotion. Targeting cytokines using biological therapy may lead to improvement of growth in some of these children, but approximately one-third continue to grow slowly. There is increasing evidence that the use of relatively high-dose recombinant human GH may lead to partial catch-up growth in chronic inflammatory conditions, although long-term follow-up data are currently limited. In this review, we comprehensively review the growth abnormalities in children with juvenile idiopathic arthritis, inflammatory bowel disease, and cystic fibrosis, systemic abnormalities of the GH-IGF axis, and growth plate perturbations. We also systematically reviewed all the current published studies of recombinant human GH in these conditions and discussed the role of recombinant human IGF-1. PMID:26720129

  9. The Performance Test of Three Different Horizontal Axis Wind Turbine (HAWT) Blade Shapes Using Experimental and Numerical Methods

    OpenAIRE

    Wen-Tong Chong; Chi-Jeng Bai; Fei-Bin Hsiao

    2013-01-01

    Three different horizontal axis wind turbine (HAWT) blade geometries with the same diameter of 0.72 m using the same NACA4418 airfoil profile have been investigated both experimentally and numerically. The first is an optimum (OPT) blade shape, obtained using improved blade element momentum (BEM) theory. A detailed description of the blade geometry is also given. The second is an untapered and optimum twist (UOT) blade with the same twist distributions as the OPT blade. The third blade is unt...

  10. Active stall control for large offshore horizontal axis wind turbines; a conceptual study considering different actuation methods

    International Nuclear Information System (INIS)

    The increasing size of Horizontal Axis Wind Turbines and the trend to install wind farms further offshore demand more robust design options. If the pitch system could be eliminated, the availability of Horizontal Axis Wind Turbines should increase. This research investigates the use of active stall control to regulate power production in replacement of the pitch system. A feasibility study is conducted using a blade element momentum code and taking the National Renewable Energy Laboratory 5 MW turbine as baseline case. Considering half of the blade span is equipped with actuators, the required change in the lift coefficient to regulate power was estimated in ΔCl = 0.7. Three actuation technologies are investigated, namely Boundary Layer Transpiration, Trailing Edge Jets and Dielectric Barrier Discharge actuators. Results indicate the authority of the actuators considered is not sufficient to regulate power, since the change in the lift coefficient is not large enough. Active stall control of Horizontal Axis Wind Turbines appears feasible only if the rotor is re-designed from the start to incorporate active-stall devices

  11. Effects of sericin on the testicular growth hormone/insulin-like growth factor-1 axis in a rat model of type 2 diabetes.

    Science.gov (United States)

    Song, Cheng-Jun; Yang, Zhen-Jun; Tang, Qi-Feng; Chen, Zhi-Hong

    2015-01-01

    This study investigated the effects of sericin on the testicular growth hormone (GH)/insulin-like growth factor-1 (IGF-1) axis in rats with type 2 diabetes mellitus. Forty rats were randomly assigned to normal control, type 2 diabetes mellitus, sericin and metformin treated groups. Type 2 diabetes was established by repeated intraperitoneal injection of streptozotocin, and identified by blood glucose ≥16.7 mmol/L at 1 week. The diabetic rats were given no other treatment, these rats in the sericin group were intragastrically perfused with 2.4 g/kg sericin and the metformin treated rats were intragastrically perfused with 55.33 mg/kg Metformin daily for 35 consecutive days. Enzyme-linked immunosorbent assays were used to determine serum testosterone, growth hormone and IGF-1 levels. Immunohistochemical staining, western blotting and reverse transcription-PCR were used to determine testicular growth hormone, growth hormone receptor and IGF-1 expression. The sericin significantly reduced serum growth hormone levels, downregulated growth hormone expression, increased serum testosterone and IGF-1 levels, and upregulated testicular growth hormone receptor and IGF-1 expression. Moreover, there were no significant differences in any of the parameters between the sericin and metformin treated groups. These findings indicated that sericin improved spermatogenic function through regulating the growth hormone/IGF-1 axis, thereby protecting reproductive function against diabetes-induced damage. PMID:26379831

  12. Role of Hypothalamic-Pituitary-Adrenal axis and corticotropin-releasing factor stress system on cue-induced relapse to alcohol seeking.

    Science.gov (United States)

    Galesi, Fernanda L; Ayanwuyi, Lydia O; Mijares, Miriam Garcia; Cippitelli, Andrea; Cannella, Nazzareno; Ciccocioppo, Roberto; Ubaldi, Massimo

    2016-10-01

    A large body of evidence has shown that the Corticotropin Releasing Factor (CRF) system, which plays a key role in stress modulation, is deeply involved in relapse to alcohol seeking induced by exposure to stressful events such as foot shock or yohimbine injections. Exposure to environmental cues is also known to be a trigger for alcohol relapse, nevertheless, the relationship between the relapse evoked by the cue-induced model and the CRF stress systems remains unclear. The purpose of this study was to evaluate, in male Wistar rats, the involvement of the CRF system and Hypothalamic-Pituitary-Adrenal (HPA) axis in relapse induced by environmental cues. Antalarmin, a selective CRF1 receptor antagonist, Metyrapone, a corticosterone (CORT) synthesis inhibitor and CORT were evaluated for their effects on the reinstatement test in a cue-induced relapse model. Antalarmin (20mg/kg) blocked relapse to alcohol seeking induced by environmental cues. Metyrapone (50 and 100mg/kg) also blocked relapse in Wistar rats but only at the highest dose (100mg/kg). Corticosterone had no effect on relapse at the doses tested. The results obtained from this study suggest that the CRF stress system and the HPA axis are involved in cue-induced alcohol relapse. PMID:27316790

  13. Dynamic knee stability estimated by finite helical axis methods during functional performance approximately twenty years after anterior cruciate ligament injury.

    Science.gov (United States)

    Grip, Helena; Tengman, Eva; Häger, Charlotte K

    2015-07-16

    Finite helical axis (FHA) measures of the knee joint during weight-bearing tasks may capture dynamic knee stability following Anterior Cruciate Ligament (ACL) injury. The aim was to investigate dynamic knee stability during two-leg squat (TLS) and one-leg side hop (SH) in a long-term follow-up of ACL injury, and to examine correlations with knee laxity (KT-1000), osteoarthritis (OA, Kellgren-Lawrence) and knee function (Lysholm score). Participants were injured 17-28 years ago and then treated with surgery (n=33, ACLR) or physiotherapy only (n=37, ACLPT) and healthy-knee controls (n=33) were tested. Movements were registered with an optical motion capture system. We computed three FHA inclination angles, its' Anterior-Posterior (A-P) position, and an index quantifying directional changes (DI), during stepwise knee flexion intervals of ∼15°. Injured knees were less stable compared to healthy controls' and to contralateral non-injured knees, regardless of treatment: the A-P intersection was more anterior (indicating a more anterior positioning of tibia relative to femur) positively correlating with high laxity/low knee function, and during SH, the FHA was more inclined relative to the flexion-extension axis, possibly due to reduced rotational stability. During the TLS, A-P intersection was more anterior in the non-injured knee than the injured, and DI was higher, probably related to higher load on the non-injured knee. ACLR had less anterior A-P intersection than ACLPT, suggesting that surgery enhanced stability, although rotational stability may remain reduced. More anterior A-P intersection and greater inclination between the FHA and the knee flexion-extension axis best revealed reduced dynamic stability ∼23 years post-injury.

  14. Overexpression of miR-200a protects cardiomyocytes against hypoxia-induced apoptosis by modulating the kelch-like ECH-associated protein 1-nuclear factor erythroid 2-related factor 2 signaling axis.

    Science.gov (United States)

    Sun, Xiaoxia; Zuo, Hong; Liu, Chunmei; Yang, Yafeng

    2016-10-01

    The kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) signaling axis plays an important role in regulating oxidative stress in ischemic cardiomyocytes. Targeting Keap1 in order to promote Nrf2 activation is considered a potential method for protecting cardiomyocytes against ischemic injury. In recent years, microRNAs (miRNAs or miRs) have emerged as powerful tools for controlling gene expression. The present study aimed to determine whether Keap1-Nrf2 was regulated by specific miRNAs in cardiomyocytes under hypoxic conditions. We demonstrated that miR-200a was significantly downregulated in ischemic myocardial tissues and hypoxic cardiomyocytes. The overexpression of miR-200a was found to protect cardiomyocytes from hypoxia-induced cell damage and the excessive production of reactive oxygen species. Through bioinformatics analysis and a dual-luciferase report assay, miR-200a was found to interact with the 3'-untranslated region of Keap1, the native regulator of Nrf2. Reverse transcription-quantitative polymerase chain reaction and western blot analysis revealed that miR-200a negatively regulated the expression of Keap1. The overexpression of miR-200a significantly increased the nuclear translocation of Nrf2 as well as downstream antioxidant enzyme gene expression. The inhibition of miR-200a displayed the opposite effects. Restoring the expression of Keap1 significantly abrogated the protective effect of miR‑200a. Taken together, these findings indicate that the suppression of Keap1 by miR-200a exerted a cardioprotective effect against hypoxia-induced oxidative stress and cell apoptosis, and suggest that the activation of Nrf2 signaling by miR‑200a represents a novel and promising therapeutic strategy for the treatment of ischemic heart disease. PMID:27573160

  15. Thyroid hormone modulation of the hypothalamic growth hormone (GH)-releasing factor-pituitary GH axis in the rat.

    OpenAIRE

    Miki, N.; Ono, M.; Hizuka, N; Aoki, T.; Demura, H

    1992-01-01

    Both thyroid hormone and hypothalamic growth hormone (GH)-releasing factor (GRF) facilitate pituitary somatotroph function. However, the pathophysiological role of thyroid hormone in GRF secretion is less well understood. Thyrotoxicosis, induced by administration of thyroxine (T4) in rats, inhibited both pituitary GH levels and immunoreactive GRF secretion from incubated hypothalamus. At the highest dose of T4 given for 12 d, GRF secretion and pituitary GH decreased by 50 and 39%, respectivel...

  16. Rearing Mozambique tilapia in tidally-changing salinities: Effects on growth and the growth hormone/insulin-like growth factor I axis.

    Science.gov (United States)

    Moorman, Benjamin P; Yamaguchi, Yoko; Lerner, Darren T; Grau, E Gordon; Seale, Andre P

    2016-08-01

    The growth hormone (GH)/insulin-like growth factor (IGF) axis plays a central role in the regulation of growth in teleosts and has been shown to be affected by acclimation salinity. This study was aimed at characterizing the effects of rearing tilapia, Oreochromis mossambicus, in a tidally-changing salinity on the GH/IGF axis and growth. Tilapia were raised in fresh water (FW), seawater (SW), or in a tidally-changing environment, in which salinity is switched between FW (TF) and SW (TS) every 6h, for 4months. Growth was measured over all time points recorded and fish reared in a tidally-changing environment grew significantly faster than other groups. The levels of circulating growth hormone (GH), insulin-like growth factor I (IGF-I), pituitary GH mRNA, gene expression of IGF-I, IGF-II, and growth hormone receptor 2 (GHR) in the muscle and liver were also determined. Plasma IGF-I was higher in FW and TS than in SW and TF tilapia. Pituitary GH mRNA was higher in TF and TS than in FW and SW tilapia. Gene expression of IGF-I in the liver and of GHR in both the muscle and liver changed between TF and TS fish. Fish growth was positively correlated with GH mRNA expression in the pituitary, and GHR mRNA expression in muscle and liver tissues. Our study indicates that rearing fish under tidally-changing salinities elicits a distinct pattern of endocrine regulation from that observed in fish reared in steady-state conditions, and may provide a new approach to increase tilapia growth rate and study the regulation of growth in euryhaline fish. PMID:27032617

  17. A five-factor model perspective on psychopathy and comorbid Axis-II disorders in a forensic-psychiatric sample.

    Science.gov (United States)

    Decuyper, Mieke; De Fruyt, Filip; Buschman, Jos

    2008-01-01

    The validity of DSM-IV predictions [Widiger, T. A., Trull, T. J., Clarkin, J. F., Sanderson, C. J., & Costa, P. T., (2002). A description of the DSM-IV personality disorders with the five-factor model of personality. In Costa, P. T. & Widiger, T. A. (Eds.), Personality disorders and the five-factor model of personality (2nd ed.). Washington DC: American Psychological Association] concerning Antisocial Personality Disorder and the validity of the hypothesized associations between the Five-Factor Model and psychopathy were examined in 48 male forensic-psychiatric patients. Prevalence of psychopathy and comorbid personality pathology was also investigated, as well as the convergent validity of two Dutch personality disorder inventories. Patients provided self-descriptions on the NEO-PI-R [Costa, P. T., & McCrae, R. R., (1992b). Professional Manual: Revised NEO Personality Inventory (NEO-PI-R) and NEO Five-Factor-Inventory (NEO-FFI). Odessa, FL: Psychological Assessment Resources], and were administered the VKP [Duijsens, I. J., Haringsma, R., & EurelingsBontekoe, E. H. M., (1999). Handleiding VKP (Vragenlijst voor kenmerken van de persoonlijkheid). Gebaseerd op DSM-IV en ICD-10. Leiderdorp: Datec] and the ADP-IV [Schotte, C. K. W., & De Doncker, D. A. M., (1994). ADP-IV Questionnaire. Antwerp Belgium: University Hospital Antwerp] to assess personality pathology. Psychopathy was assessed using Hare's Psychopathy Checklist-Revised (PCL-R; [Hare, R. D., (1990). The Hare Psychopathy Checklist Revised Manual. Toronto: Multi-Health Systems]) based on a semi-structured interview and file records of psychiatric and psychological evaluations and criminal history. Results underscored the validity of the FFM Antisocial PD associations, but the hypothesized correlations between the FFM and Psychopathy were less supported. Results supported the convergent validity of the ADP-IV and the VKP, both at the dimensional and categorical level. Around 55% met the diagnostic threshold of

  18. A New Method for Measuring Coherent Elastic Neutrino Nucleus Scattering at an Off-Axis High-Energy Neutrino Beam Target

    CERN Document Server

    Brice, S J; DeJongh, F; Empl, A; Garrison, L M; Hime, A; Hungerford, E; Kobilarcik, T; Loer, B; Mariani, C; Mocko, M; Muhrer, G; Pattie, R; Pavlovic, Z; Ramberg, E; Scholberg, K; Tayloe, R; Thornton, R T; Yoo, J; Young, A

    2013-01-01

    We present a new experimental method for measuring the process of Coherent Elastic Neutrino Nucleus Scattering (CENNS). This method uses a detector situated transverse to a high energy neutrino beam production target. This detector would be sensitive to the low energy neutrinos arising from pion decays-at-rest in the target. We discuss the physics motivation for making this measurement and outline the predicted backgrounds and sensitivities using this approach. We report a measurement of neutron backgrounds as found in an off-axis surface location of the Fermilab Booster Neutrino Beam (BNB) target. The results indicate that the Fermilab BNB target is a favorable location for a CENNS experiment.

  19. Method to rotate an endovascular device around the axis of a vessel using an external magnetic field.

    Science.gov (United States)

    Florin, E; Rangwala, H S; Rudin, S

    2007-01-01

    A magnetic guidance methodology to rotate a device around the catheter axis is proposed. The specific medical application is to intracranial aneurysms. An endovascular device, the asymmetric stent, has a low porosity region that is rotated to cover the aneurysm neck so as to reduce the blood flow into and hence obliterate the aneurysm. The magnetic guidance system consists of a magnetic device attached to the asymmetric stent and an external homogeneous magnetic field of 0.1 T. This magnetic field puts a torque on the magnetic moment of the magnetic device, thereby rotating the stent for proper orientation. For the magnetic device with the required magnetic moment of 0.001 A m2, a cylindrical neodymium permanent magnet is proposed due to its favorable material characteristics while a coil electromagnet with iron core appears impractical due to demagnetizing effects.

  20. An indirect method of studying band alignments in nBn photodetectors using off-axis electron holography

    International Nuclear Information System (INIS)

    Mid-wave and long-wave infrared nBn photodetectors with absorbers consisting of InAs/InAsSb superlattices and barriers consisting of InAs/AlGaSb(As) superlattices were grown using molecular beam epitaxy. High-resolution X-ray diffraction showing significant differences in Ga composition in the barrier layer, and different dark current behavior at 77 K, suggested the possibility of different types of band alignments between the barrier layer and the absorber for the mid- and long-wave infrared samples. Examination of the barrier layers using off-axis electron holography showed the presence of positive charge with an estimated density of 1.8 × 1017/cm3 in the mid-wave sample as a result of a type-II band alignment, whereas negligible charge was detected in the long-wave sample, consistent with a type-I band alignment

  1. Research of NPP human factors management method

    International Nuclear Information System (INIS)

    The human factors management is a complex systems engineering in the nuclear power plant. Human factors management can be divided into five parts by establishing of the model: the task, the human performance, the organization, the leadership and the feedback. Based on the research for human factors management, we can take measures to improve each part and establish human factors management system in the nuclear power plant and nuclear industry. (authors)

  2. MicroRNA-196b regulates the homeobox B7-vascular endothelial growth factor axis in cervical cancer.

    Directory of Open Access Journals (Sweden)

    Christine How

    Full Text Available The down-regulation of microRNA-196b (miR-196b has been reported, but its contribution to cervical cancer progression remains to be investigated. In this study, we first demonstrated that miR-196b down-regulation was significantly associated with worse disease-free survival (DFS for cervical cancer patients treated with combined chemo-radiation. Secondly, using a tri-modal approach for target identification, we determined that homeobox-B7 (HOXB7 was a bona fide target for miR-196b, and in turn, vascular endothelial growth factor (VEGF was a downstream transcript regulated by HOXB7. Reconstitution of miR-196b expression by transient transfection resulted in reduced cell growth, clonogenicity, migration and invasion in vitro, as well as reduced tumor angiogenesis and tumor cell proliferation in vivo. Concordantly, siRNA knockdown of HOXB7 or VEGF phenocopied the biological effects of miR-196b over-expression. Our findings have demonstrated that the miR-196b/HOXB7/VEGF pathway plays an important role in cervical cancer progression; hence targeting this pathway could be a promising therapeutic strategy for the future management of this disease.

  3. L-glutamine supplementations enhance liver glutamine-glutathione axis and heat shock factor-1 expression in endurance-exercise trained rats.

    Science.gov (United States)

    Petry, Éder Ricardo; Cruzat, Vinicius Fernandes; Heck, Thiago Gomes; Homem de Bittencourt, Paulo Ivo; Tirapegui, Julio

    2015-04-01

    Liver L-glutamine is an important vehicle for the transport of ammonia and intermediary metabolism of amino acids between tissues, particularly under catabolic situations, such as high-intensity exercise. Hence, the aim of this study was to investigate the effects of oral supplementations with L-glutamine in its free or dipeptide forms (with L-alanine) on liver glutamine-glutathione (GSH) axis, and 70 kDa heat shock proteins (HSP70)/heat shock transcription factor 1 (HSF1) expressions. Adult male Wistar rats were 8-week trained (60 min/day, 5 days/week) on a treadmill. During the last 21 days, the animals were daily supplemented with 1 g of L-glutamine/kg body weight per day in either l-alanyl-L-glutamine dipeptide (DIP) form or a solution containing L-glutamine and l-alanine in their free forms (GLN+ALA) or water (controls). Exercise training increased cytosolic and nuclear HSF1 and HSP70 expression, as compared with sedentary animals. However, both DIP and GLN+ALA supplements enhanced HSF1 expression (in both cytosolic and nuclear fractions) in relation to exercised controls. Interestingly, HSF1 rises were not followed by enhanced HSP70 expression. DIP and GLN+ALA supplements increased plasma glutamine concentrations (by 62% and 59%, respectively) and glutamine to glutamate plasma ratio in relation to trained controls. This was in parallel with a decrease in plasma ammonium levels. Supplementations increased liver GSH (by 90%), attenuating the glutathione disulfide (GSSG) to GSH ratio, suggesting a redox state protection. In conclusion, oral administration with DIP and GLN+ALA supplements in endurance-trained rats improve liver glutamine-GSH axis and modulate HSF1 pathway. PMID:25202991

  4. Clot retraction is mediated by factor XIII-dependent fibrin-αIIbβ3-myosin axis in platelet sphingomyelin-rich membrane rafts.

    Science.gov (United States)

    Kasahara, Kohji; Kaneda, Mizuho; Miki, Toshiaki; Iida, Kazuko; Sekino-Suzuki, Naoko; Kawashima, Ikuo; Suzuki, Hidenori; Shimonaka, Motoyuki; Arai, Morio; Ohno-Iwashita, Yoshiko; Kojima, Soichi; Abe, Mitsuhiro; Kobayashi, Toshihide; Okazaki, Toshiro; Souri, Masayoshi; Ichinose, Akitada; Yamamoto, Naomasa

    2013-11-01

    Membrane rafts are spatially and functionally heterogenous in the cell membrane. We observed that lysenin-positive sphingomyelin (SM)-rich rafts are identified histochemically in the central region of adhered platelets where fibrin and myosin are colocalized on activation by thrombin. The clot retraction of SM-depleted platelets from SM synthase knockout mouse was delayed significantly, suggesting that platelet SM-rich rafts are involved in clot retraction. We found that fibrin converted by thrombin translocated immediately in platelet detergent-resistant membrane (DRM) rafts but that from Glanzmann's thrombasthenic platelets failed. The fibrinogen γ-chain C-terminal (residues 144-411) fusion protein translocated to platelet DRM rafts on thrombin activation, but its mutant that was replaced by A398A399 at factor XIII crosslinking sites (Q398Q399) was inhibited. Furthermore, fibrin translocation to DRM rafts was impaired in factor XIII A subunit-deficient mouse platelets, which show impaired clot retraction. In the cytoplasm, myosin translocated concomitantly with fibrin translocation into the DRM raft of thrombin-stimulated platelets. Furthermore, the disruption of SM-rich rafts by methyl-β-cyclodextrin impaired myosin activation and clot retraction. Thus, we propose that clot retraction takes place in SM-rich rafts where a fibrin-αIIbβ3-myosin complex is formed as a primary axis to promote platelet contraction. PMID:24002447

  5. Fibroblast growth factor-2 up-regulates the expression of nestin through the Ras–Raf–ERK–Sp1 signaling axis in C6 glioma cells

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Kai-Wei [Institute of Molecular and Cellular Biology, National Taiwan University, Taipei 106, Taiwan (China); Huang, Yuan-Li [Department of Biotechnology, College of Health Science, Asia University, Taichung 413, Taiwan (China); Wong, Zong-Ruei; Su, Peng-Han [Institute of Molecular and Cellular Biology, National Taiwan University, Taipei 106, Taiwan (China); Huang, Bu-Miin [Department of Cell Biology and Anatomy, National Cheng-Kung University, Tainan 701, Taiwan (China); Ju, Tsai-Kai [Instrumentation Center, National Taiwan University, Taipei 106, Taiwan (China); Technology Commons, College of Life Science, National Taiwan University, Taipei 106, Taiwan (China); Yang, Hsi-Yuan, E-mail: hyhy@ntu.edu.tw [Institute of Molecular and Cellular Biology, National Taiwan University, Taipei 106, Taiwan (China)

    2013-05-17

    Highlights: •Nestin expression in C6 glioma cells is induced by FGF-2. •Nestin expression is induced by FGF-2 via de novo RNA and protein synthesis. •The FGFR inhibitor SU5402 blocks the FGF-2-induced nestin expression. •The mRNA of FGFR1 and 3 are detected in C6 glioma cells. •Ras–Raf–ERK–Sp1 signaling pathway is responsibe for FGF-2-induced nestin expression. -- Abstract: Nestin is a 240-kDa intermediate filament protein expressed mainly in neural and myogenic stem cells. Although a substantial number of studies have focused on the expression of nestin during development of the central nervous system, little is known about the factors that induce and regulate its expression. Fibroblast growth factor-2 (FGF-2) is an effective mitogen and stimulates the proliferation and differentiation of a subset of nestin-expressing cells, including neural progenitor cells, glial precursor cells, and smooth muscle cells. To assess whether FGF-2 is a potent factor that induces the expression of nestin, C6 glioma cells were used. The results showed that nestin expression was up-regulated by FGF-2 via de novo RNA and protein synthesis. Our RT-PCR results showed that C6 glioma cells express FGFR1/3, and FGFRs is required for FGF-2-induced nestin expression. Further signaling analysis also revealed that FGF-2-induced nestin expression is mediated through FGFR–MAPK–ERK signaling axis and the transcriptional factor Sp1. These findings provide new insight into the regulation of nestin in glial system and enable the further studies on the function of nestin in glial cells.

  6. Immune-Pineal Axis: Nuclear Factor κB (NF-kB Mediates the Shift in the Melatonin Source from Pinealocytes to Immune Competent Cells

    Directory of Open Access Journals (Sweden)

    Regina P. Markus

    2013-05-01

    Full Text Available Pineal gland melatonin is the darkness hormone, while extra-pineal melatonin produced by the gonads, gut, retina, and immune competent cells acts as a paracrine or autocrine mediator. The well-known immunomodulatory effect of melatonin is observed either as an endocrine, a paracrine or an autocrine response. In mammals, nuclear translocation of nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB blocks noradrenaline-induced melatonin synthesis in pinealocytes, which induces melatonin synthesis in macrophages. In addition, melatonin reduces NF-κB activation in pinealocytes and immune competent cells. Therefore, pathogen- or danger-associated molecular patterns transiently switch the synthesis of melatonin from pinealocytes to immune competent cells, and as the response progresses melatonin inhibition of NF-κB activity leads these cells to a more quiescent state. The opposite effect of NF-κB in pinealocytes and immune competent cells is due to different NF-κB dimers recruited in each phase of the defense response. This coordinated shift of the source of melatonin driven by NF-κB is called the immune-pineal axis. Finally, we discuss how this concept might be relevant to a better understanding of pathological conditions with impaired melatonin rhythms and hope it opens new horizons for the research of side effects of melatonin-based therapies.

  7. DRIVE AND CONTROL OF VIRTUAL-AXIS NC MACHINE TOOLS

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The structure features and driving modes of virtual-axis NC machine tools are studied.Accor- ding to different application requirements,the three-axis control method,the five-axis control method and the six-freedom control method are put forward.These results lay a foundation for the product development of the virtual-axis NC machine tools.

  8. PERSONNEL DEMOTIVATING: THE REASONS, FACTORS, ELIMINATION METHODS

    OpenAIRE

    Kuznetsova Ekaterina Andreevna

    2012-01-01

    The motivation of the personnel in any economic conditions remains a leading link in an enterprise control system. At creation of system of motivation tracking of extent of its impact on productivity of work of the personnel is important. The boomerang effect which is shown in a demotivating of separate groups of the personnel is often observed. In article features of manifestation of demotivating factors at various stages of work of the personnel are analyzed, the circle of the reasons bring...

  9. A novel segmentation method to identify left ventricular infarction in short-axis composite strain-encoded magnetic resonance images

    Science.gov (United States)

    Algohary, Ahmad O.; Metwally, Muhammad K.; El-Bialy, Ahmed M.; Kandil, Ahmed H.; Osman, Nael F.

    2011-03-01

    Composite Strain Encoding (CSENC) is a new Magnetic Resonance Imaging (MRI) technique for simultaneously acquiring cardiac functional and viability images. It combines the use of Delayed Enhancement (DE) and the Strain Encoding (SENC) imaging techniques to identify the infracted (dead) tissue and to image the myocardial deformation inside the heart muscle. In this work, a new unsupervised segmentation method is proposed to identify infarcted left ventricular tissue in the images provided by CSENC MRI. The proposed method is based on the sequential application of Bayesian classifier, Otsu's thresholding, morphological opening, radial sweep boundary tracing and the fuzzy C-means (FCM) clustering algorithm. This method is tested on images of twelve patients with and without myocardial infarction (MI) and on simulated heart images with various levels of superimposed noise. The resulting clustered images are compared with those marked up by an expert cardiologist who assisted in validating results coming from the proposed method. Infarcted myocardium is correctly identified using the proposed method with high levels of accuracy and precision.

  10. Genetically-Determined Hyperfunction of the S100B/RAGE Axis Is a Risk Factor for Aspergillosis in Stem Cell Transplant Recipients

    OpenAIRE

    Cunha, Cristina; Giovannini, Gloria; Pierini, Antonio; Alain S Bell; Sorci, Guglielmo; Riuzzi, Francesca; Donato, Rosario; Rodrigues, Fernando; Velardi, Andrea; Aversa, Franco; Romani, Luigina; Carvalho, Agostinho

    2011-01-01

    Invasive aspergillosis (IA) is a major threat to the successful outcome of hematopoietic stem cell transplantation (HSCT), although individual risk varies considerably. Recent evidence has established a pivotal role for a danger sensing mechanism implicating the S100B/receptor for advanced glycation end products (RAGE) axis in antifungal immunity. The association of selected genetic variants in the S100B/RAGE axis with susceptibility to IA was investigated in 223 consecutive patients undergoi...

  11. Regulation of the PKCθ-NF-κB Axis in T lymphocytes by the Tumor Necrosis Factor Receptor Family Member OX40

    Directory of Open Access Journals (Sweden)

    Takanori eSo

    2012-05-01

    Full Text Available Antigen primed T lymphocytes need to expand and persist to promote adaptive immunity. The growth and survival signals that control this are in large part provided by the NF-κB pathway in activated or effector/memory T cells. Although several membrane receptors impact NF-κB activation, signaling from OX40 (CD134, TNFRSF4, a member of the tumor necrosis factor receptor (TNFR superfamily, has proven to be important for T cell immunity and a strong contributor to NF-κB activity. PKCθ directs the TCR and CD28-dependent assembly of a CBM complex (CARMA1, BCL10, and MALT1 for efficient activation of NF-κB, raising the question of whether other membrane bound receptors that activate NF-κB also require this PKCθ-CBM axis to control TCR-independent T cell activity. We discuss here our recent data demonstrating that after ligation by OX40L (CD252, TNFSF4 expressed on antigen-presenting cells, OX40 translocates into detergent-insoluble membrane lipid microdomains (DIM or lipid rafts in T cells irrespective of TCR signals, and assembles into a novel signaling complex containing PKCθ, together with TRAF2, RIP1, the CBM complex, and the IKKα/β/γ complex. PKCθ is required for optimal NF-κB activation mediated by OX40 and thus works as an essential component of this OX40 signalosome. We also discuss the likelihood that other TNFR superfamily molecules might complex with PKCθ in T cells, and whether PKC isoforms may be critical to the function of TNFR molecules in general. 

  12. A new method for dual-axis fatigue testing of large wind turbine blades using resonance excitation and spectral loading

    Science.gov (United States)

    White, Darris L.

    The demand for cost effective renewable energy sources has resulted in the continual refinement of modern wind turbine designs. These refinements generally result in larger wind turbines and wind turbine blades. In order to reduce maintenance expenses, and improve quality and reliability, each new blade design must be subjected to a high cycle fatigue test. With blades expected to soon reach 70 meters in length, traditional fatigue test systems and methods are becoming less practical. Additionally, the relationship between the flap and lead-lag bending moments has not been well understood. This work explores the accuracy of current test methods compared to service loads, presents a new method for fatigue testing larger blades and experimentally validates the analysis. A dynamic model of a generic wind turbine blade and test system has been developed to evaluate the strain profiles during testing, evaluate control strategies and optimize the test accuracy. The relationship between the flap and lead-lag strains resulting from service bending moments has been analyzed. A load spectrum based on the relationship between the flap and lead-lag loads has been developed and compared to traditional test conditions. The effect of using the load spectrum on the test system stability has been analyzed and a new state-space controller has been designed. A 3-D finite element model of a generic wind turbine blade has been used to evaluate the damage accumulation for current test load conditions and the proposed load spectrum. A nonlinear damage accumulation model has been derived to evaluate the effects of load sequencing. Additionally, a new method for applying the fatigue loads to the blades has been developed and implemented. A system that applies a harmonic force at the resonance frequency of the blade in the flap direction has been designed. The new system will reduce the costs and time associated with performing a fatigue test on wind turbine blades. The new system is also

  13. The factorization method and ground state energy bounds

    Science.gov (United States)

    Schmutz, M.

    1985-04-01

    We discuss the relationship between the factorization method and the Barnsley bound to the ground state energy. The latter method is extended in such a way that both lower and upper analytic bounds can be obtained.

  14. On the amount of sieving in factorization methods

    NARCIS (Netherlands)

    Ekkelkamp, Willemina Hendrika

    2010-01-01

    Factorization methods, such as the quadratic sieve and the number field sieve, spend a lot of time on the sieving step, in which the necessary relations are collected for factoring the given number N. Relations are smooth or k-semismooth numbers (numbers with either all prime factors below some

  15. DYNAMIC CHARACTERISTIC ANALYSIS OF FUZZY- STOCHASTIC TRUSS STRUCTURES BASED ON FUZZY FACTOR METHOD AND RANDOM FACTOR METHOD

    Institute of Scientific and Technical Information of China (English)

    MA Juan; CHEN Jian-jun; XU Ya-lan; JIANG Tao

    2006-01-01

    A new fuzzy stochastic finite element method based on the fuzzy factor method and random factor method is given and the analysis of structural dynamic characteristic for fuzzy stochastic truss structures is presented. Considering the fuzzy randomness of the structural physical parameters and geometric dimensions simultaneously, the structural stiffness and mass matrices are constructed based on the fuzzy factor method and random factor method; from the Rayleigh's quotient of structural vibration, the structural fuzzy random dynamic characteristic is obtained by means of the interval arithmetic;the fuzzy numeric characteristics of dynamic characteristic are then derived by using the random variable's moment function method and algebra synthesis method. Two examples are used to illustrate the validity and rationality of the method given. The advantage of this method is that the effect of the fuzzy randomness of one of the structural parameters on the fuzzy randomness of the dynamic characteristic can be reflected expediently and objectively.

  16. A composite control method based on the adaptive RBFNN feedback control and the ESO for two-axis inertially stabilized platforms.

    Science.gov (United States)

    Lei, Xusheng; Zou, Ying; Dong, Fei

    2015-11-01

    Due to the nonlinearity and time variation of a two-axis inertially stabilized platform (ISP) system, the conventional feedback control cannot be utilized directly. To realize the control performance with fast dynamic response and high stabilization precision, the dynamic model of the ISP system is expected to match the ideal model which satisfies the desired control performance. Therefore, a composite control method based on the adaptive radial basis function neural network (RBFNN) feedback control and the extended state observer (ESO), is proposed for ISP. The adaptive RBFNN is proposed to generate the feedback control parameters online. Based on the state error information in the working process, the adaptive RBFNN can be constructed and optimized directly. Therefore, no priori training data is needed for the construction of the RBFNN. Furthermore, a linear second-order ESO is constructed to compensate for the composite disturbance. The asymptotic stability of the proposed control method has been proven by the Lyapunov stability theory. The applicability of the proposed method is validated by a series of simulations and flight tests. PMID:26434418

  17. 一种“炮身轴线偏移”检测的新方法%A New Method of Detecting Cannon Axis Excursion

    Institute of Scientific and Technical Information of China (English)

    刘庆国; 刘兴彦; 汪成

    2012-01-01

    The traditional method of detecting cannon axis excursion has some shortcomings, such as difficult to ensure accuracy, low level of automatization, etc To conquer it, in this paper a new detecting method is introduced, which combined with the technology of photoelectric coder, division circuit of steeper motor and programmable logic controller. The application feasibility of the new method is testified by the experiment of a new type of self-propelled howitzer fire system assembly and firing practice with live ammunition.%通过光电编码器、步进电机细分电路及可编程逻辑控制器技术,提出了炮身轴线偏移检测的全新方法,克服了传统方法检测精度不高、自动化程度低等不足.基于该方法研制的检测系统,经某新型自行榴弹炮火力系统装配及实弹射击检验,证明该方法是可行的.

  18. A composite control method based on the adaptive RBFNN feedback control and the ESO for two-axis inertially stabilized platforms.

    Science.gov (United States)

    Lei, Xusheng; Zou, Ying; Dong, Fei

    2015-11-01

    Due to the nonlinearity and time variation of a two-axis inertially stabilized platform (ISP) system, the conventional feedback control cannot be utilized directly. To realize the control performance with fast dynamic response and high stabilization precision, the dynamic model of the ISP system is expected to match the ideal model which satisfies the desired control performance. Therefore, a composite control method based on the adaptive radial basis function neural network (RBFNN) feedback control and the extended state observer (ESO), is proposed for ISP. The adaptive RBFNN is proposed to generate the feedback control parameters online. Based on the state error information in the working process, the adaptive RBFNN can be constructed and optimized directly. Therefore, no priori training data is needed for the construction of the RBFNN. Furthermore, a linear second-order ESO is constructed to compensate for the composite disturbance. The asymptotic stability of the proposed control method has been proven by the Lyapunov stability theory. The applicability of the proposed method is validated by a series of simulations and flight tests.

  19. Multi-Objective Structural Optimization Design of Horizontal-Axis Wind Turbine Blades Using the Non-Dominated Sorting Genetic Algorithm II and Finite Element Method

    Directory of Open Access Journals (Sweden)

    Jie Zhu

    2014-02-01

    Full Text Available A multi-objective optimization method for the structural design of horizontal-axis wind turbine (HAWT blades is presented. The main goal is to minimize the weight and cost of the blade which uses glass fiber reinforced plastic (GFRP coupled with carbon fiber reinforced plastic (CFRP materials. The number and the location of layers in the spar cap, the width of the spar cap and the position of the shear webs are employed as the design variables, while the strain limit, blade/tower clearance limit and vibration limit are taken into account as the constraint conditions. The optimization of the design of a commercial 1.5 MW HAWT blade is carried out by combining FEM analysis and a multi-objective evolutionary algorithm under ultimate (extreme flap-wise load and edge-wise load conditions. The best solutions are described and the comparison of the obtained results with the original design is performed to prove the efficiency and applicability of the method.

  20. Factors of Selection of the Stock Allocation Method

    OpenAIRE

    Rohov Heorhii K.

    2014-01-01

    The article describes results of the author's study of factors of making strategic decisions on selection of methods of stock allocation by public joint stock companies in Ukraine. The author used the Random forest mathematical apparatus of classification trees building and also informal methods. The article analyses the reasons that restrain public allocation of stock. It shows significant influence upon selection of a method of stock allocation of such factors as capital concentration, bala...

  1. A method to calculate displacement factors using SVM

    Institute of Scientific and Technical Information of China (English)

    Li Peixian; Tan Zhixiang; Yan Lili; Deng Kazhong

    2011-01-01

    In order to improve the precision of mining subsidence prediction,a mathematical model using Support Vector Machine (SVM) was established to calculate the displacement factor.The study is based on a comprehensive analysis of factors affecting the displacement factor,such as mechanical properties of the cover rock,the ratio of mining depth to seam thickness,dip angle of the coal seam and the thickness of loose layer.Data of 63 typical observation stations were used as a training and testing sample set.A SVM regression model of the displacement factor and the factors affecting it was established with a kernel function,an insensitive loss factor and a properly selected penalty factor.Given an accurate calculation algorithm for testing and analysis,the results show that an SVM regression model can calculate displacement factor precisely and reliable precision can be obtained which meets engineering requirements.The experimental results show that the method to calculation of the displacement factor,based on the SVM method,is feasible.The many factors affecting the displacement factor can be considered with this method.The research provides an efficient and accurate approach for the calculation of displacement in mining subsidence prediction.

  2. Identification of Kinematic Errors of Five-axis Machine Tool Trunnion Axis from Finished Test Piece

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ya; FU Jianzhong; CHEN Zichen

    2014-01-01

    Compared with the traditional non-cutting measurement, machining tests can more accurately reflect the kinematic errors of five-axis machine tools in the actual machining process for the users. However, measurement and calculation of the machining tests in the literature are quite difficult and time-consuming. A new method of the machining tests for the trunnion axis of five-axis machine tool is proposed. Firstly, a simple mathematical model of the cradle-type five-axis machine tool was established by optimizing the coordinate system settings based on robot kinematics. Then, the machining tests based on error-sensitive directions were proposed to identify the kinematic errors of the trunnion axis of cradle-type five-axis machine tool. By adopting the error-sensitive vectors in the matrix calculation, the functional relationship equations between the machining errors of the test piece in the error-sensitive directions and the kinematic errors of C-axis and A-axis of five-axis machine tool rotary table was established based on the model of the kinematic errors. According to our previous work, the kinematic errors of C-axis can be treated as the known quantities, and the kinematic errors of A-axis can be obtained from the equations. This method was tested in Mikron UCP600 vertical machining center. The machining errors in the error-sensitive directions can be obtained by CMM inspection from the finished test piece to identify the kinematic errors of five-axis machine tool trunnion axis. Experimental results demonstrated that the proposed method can reduce the complexity, cost, and the time consumed substantially, and has a wider applicability. This paper proposes a new method of the machining tests for the trunnion axis of five-axis machine tool.

  3. An integrating factor matrix method to find first integrals

    Energy Technology Data Exchange (ETDEWEB)

    Saputra, K V I [Faculty of Science and Mathematics, University Pelita Harapan, Jl. MH Thamrin Boulevard, Tangerang Banten, 15811 (Indonesia); Quispel, G R W [Department of Mathematics and Statistical Science, La Trobe University, Bundoora 3086 (Australia); Van Veen, L, E-mail: kie.saputra@staff.uph.ed [Faculty of Science, University of Ontario Institute of Technology, 2000 Simcoe St N., Oshawa, Ontario, L1H 7K4 (Canada)

    2010-06-04

    In this paper we develop an integrating factor matrix method to derive conditions for the existence of first integrals. We use this novel method to obtain first integrals, along with the conditions for their existence, for two- and three-dimensional Lotka-Volterra systems with constant terms. The results are compared to previous results obtained by other methods.

  4. An integrating factor matrix method to find first integrals

    CERN Document Server

    Saputra, K V I; van Veen, L

    2010-01-01

    In this paper we developed an integrating factor matrix method to derive conditions for the existence of first integrals. We use this novel method to obtain first integrals, along with the conditions for their existence, for two and three dimensional Lotka-Volterra systems with constant terms. The results are compared to previous results obtained by other methods.

  5. An analytical solution method for the unsteady, unbounded, incompressible three-dimensional Navier-Stokes equations in Cartesian coordinates using coordinate axis symmetry degeneracy

    OpenAIRE

    Abrecht, David G.

    2011-01-01

    Analytical solutions are developed for the unsteady Navier-Stokes equations for incompressible fluids in unbounded flow systems with external, time-dependent driving pressure gradients using the degeneracy of the (1 1 1) axis to reduce the inherent non-linearity of the coupled partial differential equations, which is normally performed with boundary conditions. These solutions are then extended to all directions through rotation of the reference axis, yielding a general solutio...

  6. Matrix factorization method for the Hamiltonian structure of integrable systems

    Indian Academy of Sciences (India)

    S Ghosh; B Talukdar; S Chakraborti

    2003-07-01

    We demonstrate that the process of matrix factorization provides a systematic mathematical method to investigate the Hamiltonian structure of non-linear evolution equations characterized by hereditary operators with Nijenhuis property.

  7. Option Pricing Method in a Market Involving Interval Number Factors

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The method for pricing the option in a market with interval number factors is proposed. The no-arbitrage principle in the interval number valued market and the rule to judge the reasonability of a price interval are given. Using the method, the price interval where the riskless interest and the volatility under B-S setting is given. The price interval from binomial tree model when the key factors u, d, R are all interval numbers is also discussed.

  8. Study on Axis CNC Machining Method of Marine Propellers%船用螺旋桨的四轴数控加工方法研究

    Institute of Scientific and Technical Information of China (English)

    付大鹏; 王小旭

    2013-01-01

    As the core power components of the ship, marine propellers, due to their own complex surface , and the high requirements and difficulty of machining accuracy, has been a problem in the processing area. How to use the Axis CNC machine to work out High quality propeller is the issue of our study. Put forward a new method after studying, that was correspond the different characteristics of the marine propeller surface, using the appropriate method to write the processing procedures, implementation of a program and repeated with the fourth week rotation and its rotation symmetry, can easily solve this processing problems.%船用螺旋桨作为船舶动力的核心元件,由于自身型面复杂、加工精度要求高、难度大等因素,一直是加工领域中的一个难题.如何利用四轴联动数控机床加工出高质量的船用螺旋桨是我们要研究的主要问题.经研究后提出一种新方法,即针对船用螺旋桨的各不同特征面,采用适当方法分别编写加工程序,利用其回转对称性并在第四周转动配合下反复执行个程序,可方便的解决这一加工难题.

  9. On the amount of sieving in factorization methods

    OpenAIRE

    Ekkelkamp, Willemina Hendrika

    2010-01-01

    Factorization methods, such as the quadratic sieve and the number field sieve, spend a lot of time on the sieving step, in which the necessary relations are collected for factoring the given number N. Relations are smooth or k-semismooth numbers (numbers with either all prime factors below some bound or all with the exception of at most k prime factors that do not exceed a second bound) or pairs of these type of numbers. In this thesis, we predict the amount of k-semismooth numbers needed to ...

  10. Rosenberg's Self-Esteem Scale: Two Factors or Method Effects.

    Science.gov (United States)

    Tomas, Jose M.; Oliver, Amparo

    1999-01-01

    Results of a study with 640 Spanish high school students suggest the existence of a global self-esteem factor underlying responses to Rosenberg's (M. Rosenberg, 1965) Self-Esteem Scale, although the inclusion of method effects is needed to achieve a good model fit. Method effects are associated with item wording. (SLD)

  11. Genetically-determined hyperfunction of the S100B/RAGE axis is a risk factor for aspergillosis in stem cell transplant recipients.

    Directory of Open Access Journals (Sweden)

    Cristina Cunha

    Full Text Available Invasive aspergillosis (IA is a major threat to the successful outcome of hematopoietic stem cell transplantation (HSCT, although individual risk varies considerably. Recent evidence has established a pivotal role for a danger sensing mechanism implicating the S100B/receptor for advanced glycation end products (RAGE axis in antifungal immunity. The association of selected genetic variants in the S100B/RAGE axis with susceptibility to IA was investigated in 223 consecutive patients undergoing HSCT. Furthermore, studies addressing the functional consequences of these variants were performed. Susceptibility to IA was significantly associated with two distinct polymorphisms in RAGE (-374T/A and S100B (+427C/T genes, the relative contribution of each depended on their presence in both transplantation counterparts [patient SNP(RAGE, adjusted hazard ratio (HR, 1.97; P = 0.042 and donor SNP(RAGE, HR, 2.03; P = 0.047] or in donors (SNP(S100B, HR, 3.15; P = 7.8e-(4 only, respectively. Functional assays demonstrated a gain-of-function phenotype of both variants, as shown by the enhanced expression of inflammatory cytokines in RAGE polymorphic cells and increased S100B secretion in vitro and in vivo in the presence of the S100B polymorphism. These findings point to a relevant role of the danger sensing signaling in human antifungal immunity and highlight a possible contribution of a genetically-determined hyperfunction of the S100B/RAGE axis to susceptibility to IA in the HSCT setting.

  12. Genetically-determined hyperfunction of the S100B/RAGE axis is a risk factor for aspergillosis in stem cell transplant recipients.

    Science.gov (United States)

    Cunha, Cristina; Giovannini, Gloria; Pierini, Antonio; Bell, Alain S; Sorci, Guglielmo; Riuzzi, Francesca; Donato, Rosario; Rodrigues, Fernando; Velardi, Andrea; Aversa, Franco; Romani, Luigina; Carvalho, Agostinho

    2011-01-01

    Invasive aspergillosis (IA) is a major threat to the successful outcome of hematopoietic stem cell transplantation (HSCT), although individual risk varies considerably. Recent evidence has established a pivotal role for a danger sensing mechanism implicating the S100B/receptor for advanced glycation end products (RAGE) axis in antifungal immunity. The association of selected genetic variants in the S100B/RAGE axis with susceptibility to IA was investigated in 223 consecutive patients undergoing HSCT. Furthermore, studies addressing the functional consequences of these variants were performed. Susceptibility to IA was significantly associated with two distinct polymorphisms in RAGE (-374T/A) and S100B (+427C/T) genes, the relative contribution of each depended on their presence in both transplantation counterparts [patient SNP(RAGE), adjusted hazard ratio (HR), 1.97; P = 0.042 and donor SNP(RAGE), HR, 2.03; P = 0.047] or in donors (SNP(S100B), HR, 3.15; P = 7.8e-(4)) only, respectively. Functional assays demonstrated a gain-of-function phenotype of both variants, as shown by the enhanced expression of inflammatory cytokines in RAGE polymorphic cells and increased S100B secretion in vitro and in vivo in the presence of the S100B polymorphism. These findings point to a relevant role of the danger sensing signaling in human antifungal immunity and highlight a possible contribution of a genetically-determined hyperfunction of the S100B/RAGE axis to susceptibility to IA in the HSCT setting. PMID:22114731

  13. Unascertained Factor Method of Dynamic Characteristic Analysis for Antenna Structures

    Institute of Scientific and Technical Information of China (English)

    ZHU Zeng-qing; LIANG Zhen-tao; CHEN Jian-jun

    2008-01-01

    The dynamic characteristic analysis model of antenna structures is built, in which the structural physical parameters and geometrical dimensions are all considered as unascertained variables, And a structure dynamic characteristic analysis method based on the unascertained factor method is given. The computational expression of structural characteristic is developed by the mathematics expression of unascertained factor and the principles of unascertained rational numbers arithmetic. An example is given, in which the possible values and confidence degrees of the unascertained structure characteristics are obtained. The calculated results show that the method is feasible and effective.

  14. Recent progress on the factorization method for electrical impedance tomography.

    Science.gov (United States)

    Harrach, Bastian

    2013-01-01

    The Factorization Method is a noniterative method to detect the shape and position of conductivity anomalies inside an object. The method was introduced by Kirsch for inverse scattering problems and extended to electrical impedance tomography (EIT) by Brühl and Hanke. Since these pioneering works, substantial progress has been made on the theoretical foundations of the method. The necessary assumptions have been weakened, and the proofs have been considerably simplified. In this work, we aim to summarize this progress and present a state-of-the-art formulation of the Factorization Method for EIT with continuous data. In particular, we formulate the method for general piecewise analytic conductivities and give short and self-contained proofs. PMID:24069064

  15. Fetal and Neonatal HPA Axis.

    Science.gov (United States)

    Wood, Charles E; Walker, Claire-Dominique

    2015-01-01

    Stress is an integral part of life. Activation of the hypothalamus-pituitary-adrenal (HPA) axis in the adult can be viewed as mostly adaptive to restore homeostasis in the short term. When stress occurs during development, and specifically during periods of vulnerability in maturing systems, it can significantly reprogram function, leading to pathologies in the adult. Thus, it is critical to understand how the HPA axis is regulated during developmental periods and what are the factors contributing to shape its activity and reactivity to environmental stressors. The HPA axis is not a passive system. It can actively participate in critical physiological regulation, inducing parturition in the sheep for instance or being a center stage actor in the preparation of the fetus to aerobic life (lung maturation). It is also a major player in orchestrating mental function, metabolic, and cardiovascular function often reprogrammed by stressors even prior to conception through epigenetic modifications of gametes. In this review, we review the ontogeny of the HPA axis with an emphasis on two species that have been widely studied-sheep and rodents-because they each share many similar regulatory mechanism applicable to our understanding of the human HPA axis. The studies discussed in this review should ultimately inform us about windows of susceptibility in the developing brain and the crucial importance of early preconception, prenatal, and postnatal interventions designed to improve parental competence and offspring outcome. Only through informed studies will our public health system be able to curb the expansion of many stress-related or stress-induced pathologies and forge a better future for upcoming generations.

  16. An efficient block variant of robust structured multifrontal factorization method

    Institute of Scientific and Technical Information of China (English)

    Zuo Xian-Yu; Mo Ze-Yao; Gu Tong-Xiang

    2013-01-01

    Based on the two-dimensional three-temperature (2D3T) radiation diffusion equations and its discrete system,using the block diagonal structure of the three-temperature matrix,the reordering and symbolic decomposition parts of the RSMF method are replaced with corresponding block operation in order to improve the solution efficiency.We call this block form method block RSMF (in brief,BRSMF) method.The new BRSMF method not only makes the reordering and symbolic decomposition become more effective,but also keeps the cost of numerical factorization from increasing and ensures the precision of solution very well.The theoretical analysis of the computation complexity about the new BRSMF method shows that the solution efficiency about the BRSMF method is higher than the original RSMF method.The numerical experiments also show that the new BRSMF method is more effective than the original RSMF method.

  17. Complex Factorizations of the Lucas Sequences via Matrix Methods

    Directory of Open Access Journals (Sweden)

    Honglin Wu

    2014-01-01

    Full Text Available Firstly, we show a connection between the first Lucas sequence and the determinants of some tridiagonal matrices. Secondly, we derive the complex factorizations of the first Lucas sequence by computing those determinants with the help of Chebyshev polynomials of the second kind. Furthermore, we also obtain the complex factorizations of the second Lucas sequence by the similar matrix method using Chebyshev polynomials of the first kind.

  18. An efficient method for identification of risk factors

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    This paper presents a method to identify risk factors during bridge construction.The method integrates the concepts of analytical hierarchy process and fuzzy consistent matrix method.The advantage of the method is that instead of using 9-point scale of relative importance of the conventional analytical hierarchy process,it uses a 3-point scale to describe the scale of importance,thus greatly simplifying the identification problem of risk factors.Moreover,the difficulties of making judgment and comparison caused by uncertainty that jeopardizes the accuracy of the results in the conventional analytical hierarchy process can also be overcome.Another advantage of the method is that it does not involve consistency checking,thus saving a large amount of CPU time.It has been demonstrated with a numerical example that the proposed fuzzy analytical hierarchy process based on 3-point scale can offer significant computational savings over the conventional analytical hierarchy process.

  19. Improved response factor methods for seismic fragility of reactor building

    International Nuclear Information System (INIS)

    A seismic probabilistic risk assessment (PRA) method has been applied to evaluate the safety of nuclear reactor buildings during earthquakes. Improvement was made to two methods (based on linear response and based on non-linear response) of fragility analysis in seismic PRA. The conventional method, which is based on linear response, considers increases of seismic capacity implicitly, using the non-linear behaviour of the structure. We described how to evaluate the capacity increasing factor for the linear response method. Secondly, we proposed a method based on the non-linear response and a stratified two-point estimation method which can efficiently evaluate the variability of non-linear responses. We applied the two method to a PWR-type nuclear reactor building and ascertained that these method are useful and effective. (orig.)

  20. Cancer family history reporting: impact of method and psychosocial factors.

    Science.gov (United States)

    Kelly, Kimberly M; Shedlosky-Shoemaker, Randi; Porter, Kyle; Remy, Amber; DeSimone, Philip; Andrykowski, Michael A

    2007-06-01

    Family history is one the greatest risk factors for disease and one of the most important informational tools in medical genetics for the purpose of diagnosis, risk assessment, prevention and treatment. However, research is needed on the comparability of different methods of cancer family history assessment and the influence of psychosocial factors in family history reports. The purpose of this study was to determine if individuals had discrepancies between written and interview reports of cancer family history and the role of psychosocial factors in these discrepancies. Oncology patients (n=104) were administered a survey to assess psychosocial factors (i.e., information-seeking, worry, perceived risk, and health literacy) and were asked to provide family history in a written and an interview form. Randomization determined which form individuals received first. No differences in the amount of missing data or the amount of unspecified data were noted between the written and interview method. Psychosocial factors did not differentiate between those who had discrepancies in family history reports and those who did not have discrepancies in family history reports; although there was a trend for those with lower literacy and those who were blunters to be more discrepant on type of cancer diagnosis. In sum, this preliminary study indicates that written and interview methods of family history assessment for first degree relatives may be used interchangeably. The ability to use written methods will facilitate collection of basic family history information in the oncology clinic. PMID:17318453

  1. Caloric restriction-associated remodeling of rat white adipose tissue: effects on the growth hormone/insulin-like growth factor-1 axis, sterol regulatory element binding protein-1, and macrophage infiltration

    OpenAIRE

    Chujo, Yoshikazu; Fujii, Namiki; Okita, Naoyuki; Konishi, Tomokazu; Narita, Takumi; Yamada, Atsushi; Haruyama, Yushi; Tashiro, Kosuke; Chiba, Takuya; Shimokawa, Isao; Higami, Yoshikazu

    2012-01-01

    The role of the growth hormone (GH)-insulin-like growth factor (IGF)-1 axis in the lifelong caloric restriction (CR)-associated remodeling of white adipose tissue (WAT), adipocyte size, and gene expression profiles was explored in this study. We analyzed the WAT morphology of 6–7-month-old wild-type Wistar rats fed ad libitum (WdAL) or subjected to CR (WdCR), and of heterozygous transgenic dwarf rats bearing an anti-sense GH transgene fed ad libitum (TgAL) or subjected to CR (TgCR). Although ...

  2. Bleeding after endoscopic submucosal dissection: Risk factors and preventive methods

    Science.gov (United States)

    Kataoka, Yosuke; Tsuji, Yosuke; Sakaguchi, Yoshiki; Minatsuki, Chihiro; Asada-Hirayama, Itsuko; Niimi, Keiko; Ono, Satoshi; Kodashima, Shinya; Yamamichi, Nobutake; Fujishiro, Mitsuhiro; Koike, Kazuhiko

    2016-01-01

    Endoscopic submucosal dissection (ESD) has become widely accepted as a standard method of treatment for superficial gastrointestinal neoplasms because it enables en block resection even for large lesions or fibrotic lesions with minimal invasiveness, and decreases the local recurrence rate. Moreover, specimens resected in an en block fashion enable accurate histological assessment. Taking these factors into consideration, ESD seems to be more advantageous than conventional endoscopic mucosal resection (EMR), but the associated risks of perioperative adverse events are higher than in EMR. Bleeding after ESD is the most frequent among these adverse events. Although post-ESD bleeding can be controlled by endoscopic hemostasis in most cases, it may lead to serious conditions including hemorrhagic shock. Even with preventive methods including administration of acid secretion inhibitors and preventive hemostasis, post-ESD bleeding cannot be completely prevented. In addition high-risk cases for post-ESD bleeding, which include cases with the use of antithrombotic agents or which require large resection, are increasing. Although there have been many reports about associated risk factors and methods of preventing post-ESD bleeding, many issues remain unsolved. Therefore, in this review, we have overviewed risk factors and methods of preventing post-ESD bleeding from previous studies. Endoscopists should have sufficient knowledge of these risk factors and preventive methods when performing ESD.

  3. A comparison of computational methods for identifying virulence factors.

    Directory of Open Access Journals (Sweden)

    Lu-Lu Zheng

    Full Text Available Bacterial pathogens continue to threaten public health worldwide today. Identification of bacterial virulence factors can help to find novel drug/vaccine targets against pathogenicity. It can also help to reveal the mechanisms of the related diseases at the molecular level. With the explosive growth in protein sequences generated in the postgenomic age, it is highly desired to develop computational methods for rapidly and effectively identifying virulence factors according to their sequence information alone. In this study, based on the protein-protein interaction networks from the STRING database, a novel network-based method was proposed for identifying the virulence factors in the proteomes of UPEC 536, UPEC CFT073, P. aeruginosa PAO1, L. pneumophila Philadelphia 1, C. jejuni NCTC 11168 and M. tuberculosis H37Rv. Evaluated on the same benchmark datasets derived from the aforementioned species, the identification accuracies achieved by the network-based method were around 0.9, significantly higher than those by the sequence-based methods such as BLAST, feature selection and VirulentPred. Further analysis showed that the functional associations such as the gene neighborhood and co-occurrence were the primary associations between these virulence factors in the STRING database. The high success rates indicate that the network-based method is quite promising. The novel approach holds high potential for identifying virulence factors in many other various organisms as well because it can be easily extended to identify the virulence factors in many other bacterial species, as long as the relevant significant statistical data are available for them.

  4. The crowding factor method applied to parafoveal vision

    Science.gov (United States)

    Ghahghaei, Saeideh; Walker, Laura

    2016-01-01

    Crowding increases with eccentricity and is most readily observed in the periphery. During natural, active vision, however, central vision plays an important role. Measures of critical distance to estimate crowding are difficult in central vision, as these distances are small. Any overlap of flankers with the target may create an overlay masking confound. The crowding factor method avoids this issue by simultaneously modulating target size and flanker distance and using a ratio to compare crowded to uncrowded conditions. This method was developed and applied in the periphery (Petrov & Meleshkevich, 2011b). In this work, we apply the method to characterize crowding in parafoveal vision (crowding than in the periphery, yet radial/tangential asymmetries are clearly preserved. There are considerable idiosyncratic differences observed between participants. The crowding factor method provides a powerful tool for examining crowding in central and peripheral vision, which will be useful in future studies that seek to understand visual processing under natural, active viewing conditions. PMID:27690170

  5. Guiding Architectural Decisions with the Influencing Factors Method

    OpenAIRE

    Stoll, Pia; Wall, Anders; Norström, Christer

    2008-01-01

    The Influencing Factors (IF) method guides the architect through stakeholders’ concerns to architectural decisions in line with current business goals. The result is a set of requirements on software quality attributes and business goals and highlighted trade-offs among software quality attributes and among business goals. The IF method is suitable for sustainable software systems since it allows new concerns, resulting from changes in business goals, stakeholder concerns, technical environme...

  6. Crime vs. demographic factors revisited: Application of data mining methods

    Directory of Open Access Journals (Sweden)

    Xingan Li

    2015-06-01

    Full Text Available The aim of this article is to inquire about correlations between criminal phenomena and demographic factors. This international-level comparative study used a dataset covering 56 countries and 28 attributes. The data were processed with the Self-Organizing Map (SOM, assisted other clustering methods, and several statistical methods for obtaining comparable results. The article is an exploratory application of the SOM in mapping criminal phenomena through processing of multivariate data. We found out that SOM was able to group efficiently the present data and characterize these different groups. Other machine learning methods were applied to ensure groups computed with SOM. The correlations obtained between attributes were chiefly weak.

  7. Alternating proximal gradient method for nonnegative matrix factorization

    CERN Document Server

    Xu, Yangyang

    2011-01-01

    Nonnegative matrix factorization has been widely applied in face recognition, text mining, as well as spectral analysis. This paper proposes an alternating proximal gradient method for solving this problem. With a uniformly positive lower bound assumption on the iterates, any limit point can be proved to satisfy the first-order optimality conditions. A Nesterov-type extrapolation technique is then applied to accelerate the algorithm. Though this technique is at first used for convex program, it turns out to work very well for the non-convex nonnegative matrix factorization problem. Extensive numerical experiments illustrate the efficiency of the alternating proximal gradient method and the accleration technique. Especially for real data tests, the accelerated method reveals high superiority to state-of-the-art algorithms in speed with comparable solution qualities.

  8. Synthesis and properties of highly c-axis oriented PbTiO3 thin films prepared by and MOCVD method

    Science.gov (United States)

    Chen, Xian-Tong; Yamane, Hisanori; Kaya, Kiyoshi

    1992-08-01

    Thin films of PbTiO3 were prepared on MgO(100) substrates by chemical vapor deposition using Pb(C2H5)4 (PbEt) and Ti(OC3H7)4 (TTIP) as sources. With decreasing Pb/Ti molar ratio from 1.2 to 1 the degree of c-axis orientation increased. Highly c-axis oriented PbTiO3 thin films were epitaxially grown at 500°C and 2 kPa. The films were transparent and had a refractive index (n) of 2.64 at 632.8 nm which was about 2% lower than that of a single PbTiO3 crystal (n ≈ 2.7). The films prepared on (100)-oriented Pt electrodes deposited on MgO(100) substrates at 600°C and 2 kPa also showed a prominent c-axis orientation and had a dielectric constant of 90.

  9. Parathyroid hormone-mitogen-activated protein kinase axis exerts fibrogenic effect of connective tissue growth factor on human renal proximal tubular cells

    Institute of Scientific and Technical Information of China (English)

    GUO Yun-shan; YUAN Wei-jie; ZHANG Ai-ping; DING Yao-hai; WANG Yan-xia

    2010-01-01

    Background Enhanced and prolonged expression of connective tissue growth factor (CTGF) is associated with kidney fibrosis. Parathyroid hormone (PTH) is involved in the genesis of disturbed calcium/phosphate metabolism and ostitis fibrosa in renal failure. PTH activated mitogen-activated protein kinase (MAPK) signaling pathway is present in renal tubular cells. The aim of this study was to identify the mechanism how the signal is transduced to result in extracellular signal-regulated protein kinase (ERK) activation, leading to upregulation of CTGF.Methods The levels of CTGF mRNA and protein in human kidney proximal tubular cells (HK-2) treated with PTH in the presence or absence of the MAPK inhibitor PD98059 were analyzed by quantitative real-time polymerase chain reaction (RT-PCR) and immunoblotting assay. The activation of the CTGF promoter in HK-2 cells was determined by the dual-luciferase assay. The effects of the protein kinase A (PKA) activator 8-Br-cAMP and protein kinase C (PKC) activator phorbol 12-myristate 13-acetate (PMA) on MAPK phosphorylation, and the effects of the PKA inhibitor H89 and PKC inhibitor calphostin C on MAPK phosphorylation and CTGF expression were detected by immunoblotting assay.Results PD98059 inhibited the PTH stimulated expression of CTGF, which strongly suggested that the MAPK signaling pathway plays an important role in the PTH-induced CTGF upregulation in renal tubular cells. A PKA activator as well as PKC activators induced MAPK phosphorylation, and both PKA and PKC inhibitors antagonized PTH-induced MAPK phosphorylation and CTGF expression.Conclusion CTGF expression is upregulated by PTH through a PKC/PKA-ERK-dependent pathway.

  10. Lift Augmentation for Vertical Axis Wind Turbines

    Directory of Open Access Journals (Sweden)

    Gerald M Angle II

    2010-12-01

    turbine’s rotation. Though this technology can be applied to any wind turbine, whether horizontal or vertical axis, this paper focuses on the application of circulation control for VAWT’s due primarily to reduced hardware complexities and to increase the performance of this design thus helping to level the playing field between the two styles. This performance enhancement coupled with the ability to locate the primary components near the ground allows for easier installation, troubleshooting, maintenance, and future improvement of the circulation control sub-system. By varying the circulation control performance with the blade position, the coefficient of performance, Cp, of the wind turbine can be altered. This variation in Cp resembles a change in the effective solidity factor, the non-dimensional characteristic that accounts for the number of turbine blades, chord length, and turbine radius. The solidity factor is typically used in the design of a wind turbine with its peak performance occurring at various tip speed ratios, at different solidity factors. Prior to the construction of physical models, analytical methods, namely a vortex model, was used to estimate the performance enhancement potential of the blade force augmentation via circulation control. These results were then used to construct and test a wind tunnel blade section model to obtain lift and drag values for a full range of rotational angles. These results were then supplied to the vortex model which indicated that through the addition of circulation control to the blades of a vertical axis wind turbine an approximately 20% improvement in the annual energy production, and consequently the capacity factor, could be achieved.

  11. Intercomparison of selected fixed-area areal reduction factor methods

    Science.gov (United States)

    Pavlovic, Sandra; Perica, Sanja; St Laurent, Michael; Mejía, Alfonso

    2016-06-01

    The areal reduction factor (ARF) is a concept used in many hydrologic designs to transform a point precipitation frequency estimate of a given duration and frequency to a corresponding areal estimate. Various methods have been proposed in the literature to calculate ARFs. Proposed ARFs could vary significantly, and it is unclear if discrepancies are primarily due to differences in methodologies, the dissimilar datasets used to calculate ARFs, or if they originate from regional uniqueness. Our goal in this study is to analyze differences among ARFs derived from different types of fixed-area ARF methods, which are suitable for use with precipitation frequency estimates. For this intercomparison, all the ARFs were computed using the same, high-quality rainfall-radar merged dataset for a common geographic region. The selected ARFs methods represent four commonly used approaches: empirical methods, methods that are based on the spatial correlation structure of rainfall, methods that rely on the scaling properties of rainfall in space and time, and methods that utilize extreme value theory. The state of Oklahoma was selected as the study area, as it has a good quality radar data and a dense network of rain gauges. Results indicate significant uncertainties in the ARF estimates, regardless of the method used. Even when calculated from the same dataset and for the same geographic area, the ARF estimates from the selected methods differ. The differences are more pronounced for the shorter durations and larger areas. Results also indicate some ARF dependence on the average recurrence intervals.

  12. Dirac equation in low dimensions: The factorization method

    Science.gov (United States)

    Sánchez-Monroy, J. A.; Quimbay, C. J.

    2014-11-01

    We present a general approach to solve the (1 + 1) and (2 + 1) -dimensional Dirac equations in the presence of static scalar, pseudoscalar and gauge potentials, for the case in which the potentials have the same functional form and thus the factorization method can be applied. We show that the presence of electric potentials in the Dirac equation leads to two Klein-Gordon equations including an energy-dependent potential. We then generalize the factorization method for the case of energy-dependent Hamiltonians. Additionally, the shape invariance is generalized for a specific class of energy-dependent Hamiltonians. We also present a condition for the absence of the Klein paradox (stability of the Dirac sea), showing how Dirac particles in low dimensions can be confined for a wide family of potentials.

  13. [ELISA method for the determination of factor VII antigen].

    Science.gov (United States)

    Jorquera, J I; Aznar, J A; Monteagudo, J; Montoro, J M; Casaña, P; Pascual, I; Bañuls, E; Curats, R; Llopis, F

    1989-12-01

    The low plasma concentration of clotting factor VII makes it difficult to assay its antigenic fraction by the conventional methods of precipitation with specific antigens. Simple and peroxidase-conjugated antisera are currently available from commercial sources, thus allowing one to determine F VII:Ag by enzyme immunoassay. An ELISA method has been developed in this laboratory which provides sensitivity limits about 0.1% of the plasma concentration of F VII and correlates significantly with its functional activity (r = 0.603, n = 44, p less than 0.001). This technique can be highly helpful in characterising molecular variants of F VII, as well as in detecting acquired deficiencies of this factor.

  14. A factorization method for the classification of infrared spectra

    Directory of Open Access Journals (Sweden)

    Kammerer Bernd

    2010-11-01

    Full Text Available Abstract Background Bioinformatics data analysis often deals with additive mixtures of signals for which only class labels are known. Then, the overall goal is to estimate class related signals for data mining purposes. A convenient application is metabolic monitoring of patients using infrared spectroscopy. Within an infrared spectrum each single compound contributes quantitatively to the measurement. Results In this work, we propose a novel factorization technique for additive signal factorization that allows learning from classified samples. We define a composed loss function for this task and analytically derive a closed form equation such that training a model reduces to searching for an optimal threshold vector. Our experiments, carried out on synthetic and clinical data, show a sensitivity of up to 0.958 and specificity of up to 0.841 for a 15-class problem of disease classification. Using class and regression information in parallel, our algorithm outperforms linear SVM for training cases having many classes and few data. Conclusions The presented factorization method provides a simple and generative model and, therefore, represents a first step towards predictive factorization methods.

  15. Insulin-like factor 3 levels in cord blood and serum from children: effects of age, postnatal hypothalamic-pituitary-gonadal axis activation, and cryptorchidism

    DEFF Research Database (Denmark)

    Bay, Katrine; Virtanen, Helena E; Hartung, Stefan;

    2007-01-01

    The Leydig cell hormone insulin-like factor 3 (INSL3) is important for testicular descent. Currently INSL3 levels in cord blood, in serum throughout childhood, and in relation to congenital cryptorchidism are unknown....

  16. Contraceptive Methods and Factors Associated with Modern Contraceptive In Use

    Directory of Open Access Journals (Sweden)

    Hammad Ali Qazi

    2010-03-01

    Full Text Available Objective: The world population will likely increase by 2.5 billion over the next 43 years, passing from the current 6.7 billion to 9.2 billion in 2050. Only limited information about the contraceptive practices especially modern contraceptive use is available. The aim of this study is to determine the prevalence of contraceptive methods and factors associated with modern contraceptive in useMaterials and Methods: A cross sectional study of 288 females selected through consecutive sampling was conducted in Jinnah Post graduate Medical Center family reproductive health care center Karachi, Pakistan from November 2008 to January 2009. Females of reproductive age 16-50 years using any contraceptive measures and giving informed consent were included. Those who with severe debilitating disease, having any physical and mental disability were excluded. Two trained co researchers interviewed the participants for socio demographic reasons. The main outcome variables of the study were comparing modern and traditional contraceptive methods and factors associated with modern contraceptive in use.Results: The results showed mean age of contraceptive users was 29.49 (±6.42 years. Modern contraceptive method was used by 216 (75% and traditional method by 72 (25%. Final multiple logistic regression showed that a few factors have influence on usage rate including: age>30 years [AOR, 0.426 95% CI0.209-0.865], addiction [AOR, 0.381 95% CI0.173-0.839], and means of information like family planning worker (FPW [AOR, 6.315 95% CI 3.057-13.046], Television (TV [AOR, 0.402 95% CI 0.165-0.979] and billboard (BB [AOR, 0.207 95% CI 0.066-0.447].Conclusion: Modern contraceptive method use is very common in our region (75%. The important means of information for modern contraceptive in use were GPs and family planning workers.

  17. Insulin-like factor 3 levels in cord blood and serum from children: effects of age, postnatal hypothalamic-pituitary-gonadal axis activation, and cryptorchidism

    DEFF Research Database (Denmark)

    Bay, Katrine; Virtanen, Helena E; Hartung, Stefan;

    2007-01-01

    The Leydig cell hormone insulin-like factor 3 (INSL3) is important for testicular descent. Currently INSL3 levels in cord blood, in serum throughout childhood, and in relation to congenital cryptorchidism are unknown.......The Leydig cell hormone insulin-like factor 3 (INSL3) is important for testicular descent. Currently INSL3 levels in cord blood, in serum throughout childhood, and in relation to congenital cryptorchidism are unknown....

  18. Evaluation of methods for modeling transcription factor sequence specificity

    OpenAIRE

    Weirauch, Matthew T; Cote, Atina; Norel, Raquel; Annala, Matti; Zhao, Yue; Riley, Todd R; Saez-Rodriguez, Julio; Cokelaer, Thomas; Vedenko, Anastasia; Talukder, Shaheynoor; Agius, Phaedra; Arvey, Aaron; Bucher, Philipp; Callan, Curtis G.; Chang, Cheng Wei

    2013-01-01

    Genomic analyses often involve scanning for potential transcription factor (TF) binding sites using models of the sequence specificity of DNA binding proteins. Many approaches have been developed to model and learn a protein's DNA-binding specificity, but these methods have not been systematically compared. Here we applied 26 such approaches to in vitro protein binding microarray data for 66 mouse TFs belonging to various families. For nine TFs, we also scored the resulting motif models on in...

  19. An AHP method for identifying influential factors on insurance cost

    OpenAIRE

    Firouzeh Azizi; Mehdi Jafarzadeh Kenari; Mehri Nasiri

    2013-01-01

    During the past few years, there have been increasing competitions in insurance firms around the world and most insurance firms try to find appropriate methods to reduce the cost of their products. In this paper, we perform an empirical investigation to find important factors influencing cost management in insurance industry. The proposed study of this paper detects five items including human productivity, economic inflation, competitions within industry, information technology and rate of da...

  20. Dirac equation in low dimensions: The factorization method

    Energy Technology Data Exchange (ETDEWEB)

    Sánchez-Monroy, J.A., E-mail: antosan@if.usp.br [Instituto de Física, Universidade de São Paulo, 05508-090, São Paulo, SP (Brazil); Quimbay, C.J., E-mail: cjquimbayh@unal.edu.co [Departamento de Física, Universidad Nacional de Colombia, Bogotá, D. C. (Colombia); CIF, Bogotá (Colombia)

    2014-11-15

    We present a general approach to solve the (1+1) and (2+1)-dimensional Dirac equations in the presence of static scalar, pseudoscalar and gauge potentials, for the case in which the potentials have the same functional form and thus the factorization method can be applied. We show that the presence of electric potentials in the Dirac equation leads to two Klein–Gordon equations including an energy-dependent potential. We then generalize the factorization method for the case of energy-dependent Hamiltonians. Additionally, the shape invariance is generalized for a specific class of energy-dependent Hamiltonians. We also present a condition for the absence of the Klein paradox (stability of the Dirac sea), showing how Dirac particles in low dimensions can be confined for a wide family of potentials. - Highlights: • The low-dimensional Dirac equation in the presence of static potentials is solved. • The factorization method is generalized for energy-dependent Hamiltonians. • The shape invariance is generalized for energy-dependent Hamiltonians. • The stability of the Dirac sea is related to the existence of supersymmetric partner Hamiltonians.

  1. INFLUENCE FACTORS STUDY ON THE AERODYNAMIC PERFORMANCE OF A HORIZONTAL AXIS WIND TURBINE ROTOR%水平轴风机气动性能影响因素研究

    Institute of Scientific and Technical Information of China (English)

    李军向; 薛忠民; 王继辉

    2008-01-01

    设计高性能水平轴风机是如今风机设计的趋势.风机工作环境恶劣,要计算所有因素对风机性能的影响不太现实.本文运用动量理论和叶素理论分析了实度、桨矩角、锥角、倾角和叶片厚度对风轮气动性能的影响.分析表明,风轮气动性能对实度、桨矩角敏感度高,叶片厚度对风轮气动性能影响不大.对敏感参数进行优化设计,有利于风机在低成本情况下提高其性能.%High aerodynamic performance is desirable for a horizontal axis wind turbine design. Wind turbine including rotor with complicated structure works in a quite execrable condition, it is unpractical to calculate the aerodynamic performance with all influence factors considered. In this paper, the effects of various factors including solidity, pitch angle, cone angle, tilt angle, yaw angle and blade thickness on the aerodynamic performance of horizontal axis wind turbine rotor were analyzed based on momentum and blade element theory. Such investigation shows that the aerodynamic performance is sensitive to some factors, and others not. Proper parameters can be selected to optimize the design of a wind turbine to capture as much energy from wind as possible with low cost.

  2. Dynamic transitions in a model of the hypothalamic-pituitary-adrenal axis

    Science.gov (United States)

    Čupić, Željko; Marković, Vladimir M.; Maćešić, Stevan; Stanojević, Ana; Damjanović, Svetozar; Vukojević, Vladana; Kolar-Anić, Ljiljana

    2016-03-01

    Dynamic properties of a nonlinear five-dimensional stoichiometric model of the hypothalamic-pituitary-adrenal (HPA) axis were systematically investigated. Conditions under which qualitative transitions between dynamic states occur are determined by independently varying the rate constants of all reactions that constitute the model. Bifurcation types were further characterized using continuation algorithms and scale factor methods. Regions of bistability and transitions through supercritical Andronov-Hopf and saddle loop bifurcations were identified. Dynamic state analysis predicts that the HPA axis operates under basal (healthy) physiological conditions close to an Andronov-Hopf bifurcation. Dynamic properties of the stress-control axis have not been characterized experimentally, but modelling suggests that the proximity to a supercritical Andronov-Hopf bifurcation can give the HPA axis both, flexibility to respond to external stimuli and adjust to new conditions and stability, i.e., the capacity to return to the original dynamic state afterwards, which is essential for maintaining homeostasis. The analysis presented here reflects the properties of a low-dimensional model that succinctly describes neurochemical transformations underlying the HPA axis. However, the model accounts correctly for a number of experimentally observed properties of the stress-response axis. We therefore regard that the presented analysis is meaningful, showing how in silico investigations can be used to guide the experimentalists in understanding how the HPA axis activity changes under chronic disease and/or specific pharmacological manipulations.

  3. Fish oil supplementation from 9 to 18 months of age affects the insulin-like growth factor axis in a sex-specific manner in Danish infants

    DEFF Research Database (Denmark)

    Damsgaard, Camilla T.; Harsløf, Laurine B. S.; Andersen, Anders D.;

    2016-01-01

    Several studies have investigated the effects of fish oil (FO) on infant growth, but little is known about the effects of FO and sex on insulin-like growth factor-1 (IGF-1), the main regulator of growth in childhood. We explored whether FO v. sunflower oil (SO) supplementation from 9 to 18 months...

  4. A survey on critical factors influencing new advertisement methods

    Directory of Open Access Journals (Sweden)

    Naser Azad

    2013-02-01

    Full Text Available Soft drink beverages are important part of many people’s foods and many prefer soft drink to water when they have dinner. Therefore, this business model can be considered as the longest lasting sector for many years and there has been not much change in these products. However, new methods of advertisement play important role for increasing market share. In this paper, we study the impact of new methods of advertisement in product development. The proposed study of this paper designs a questionnaire for one of Iranian soft drink producers, which consisted of 274 questions in Likert scale and uses factor analysis (FA to analyze the results. The study selects 250 people who live in city of Tehran, Iran and Cronbach alpha has been calculated as 0.88, which is well above the minimum desirable limit. According to our results, there were six important factors impacting in product development, including modern advertisement techniques, emotional impact, strategy of market leadership, pricing strategy, product life chain and supply entity. The most important factor loading in these six components include impact of social values, persuading unaware and uninformed customers, ability to monopolizing in production, improving pricing techniques, product life cycle and negative impact of high advertisement.

  5. Association between Social and Demographic Factors with Feeding Methods in

    Directory of Open Access Journals (Sweden)

    Maryam Gholamalizadeh

    2013-03-01

    Full Text Available Background: Healthy Nutrition has an important role in childhood. Food habits of a child probably will continue to adulthood and increase the risk of many chronic diseases. Role of parents in child nutrition as a food producer and eating pattern has recognized to most important factor of child nutrition. Recent studies have shown that the methods used by parents to child feeding have an important role in the child’s diet and BMI. This paper aimed to investigate which parents use which types of parenting control practices to manage their children’s nutrition. Materials and Methods: A cross-sectional survey of 208 parents with children aged 3-6 years was carried out in 30 primary schools. Measures included demographic and social factors and aspects of child feeding practices.Results: Results showed that stay at home mothers used more modeling practices. Mothers of sons used more pressure to eat than others. Older mothers used less pressure to eat. Mothers with higher BMI used more emotion regulation strategy and less modeling. And mothers with more education used more modeling.Conclusion: The results showed a significant relationship between demographic and social factors with aspects of the feeding practices.

  6. Micromachined dual input axis rate gyroscope

    Science.gov (United States)

    Juneau, Thor Nelson

    electrostatic forces over power the beam suspension. Multivariable design optimization is used to maximize performance given process constraints. All electronics needed to sustain rotor oscillation, control oscillation amplitude, sense rotor tilting due to Coriolis acceleration, and process sense signals to produce voltage outputs are explained. A voltage controlled oscillator slaved to the structure oscillation through a phase-lock-loop is used as the master clock to produce all signals needed for signal processing and amplitude control. Thus, the micromachine serves as both a rotation sensor and a frequency reference. Final versions fabricated by Sandia National Laboratory were fully integrated and therefore required only passive components and electrical sources off-chip. Without electrostatic tuning, dual-axis rate gyroscopes achieved 0.1sp°/sec/sqrt{Hz} noise level. This provided automotive grade performance of approximately 1sp°/sec noise floor over a 100 Hz bandwidth. Electrical tuning decreased noise to below 0.02sp°/sec/sqrt{Hz}. However, open-loop operation with nearly matched sense and drive modes can result in higher cross-axis sensitivity, scale factor drift, and phase errors. Closed-loop feedback methods which alleviate these problems as well as reduce offset drift due to quadrature error are presented as future directions.

  7. Development of a cutset factorization method to minimize cutset structure

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Woo Sik [Sejong University, Seoul (Korea, Republic of)

    2015-10-15

    In Probabilistic Safety Assessment (PSA) of nuclear power plants, (1) event trees and fault trees are modelled for the accident scenarios, (2) Minimal Cut Sets (MCSs) are calculated from the integrated fault trees, (3) MCS post-processing is performed to delete impossible MCSs and manipulate human errors, and (4) core damage frequency is finally calculated from these post-processed MCSs. Regular fault tree solvers restructure a fault tree, convert it into a modularized one, generate modularized MCSs from the modularized fault tree, and expands modules in MCSs. These modularized MCSs should be expanded for performing MCS post-processing. It is well known that post-processed MCSs cannot be easily modularized. This paper proposes a new method to factorize MCSs. Importance measures are employed for the acceleration of this factorization. The benchmarks tests showed the effectiveness of this algorithm. The algorithm in this paper minimizes computational memory and quickly detects modules in MCSs.

  8. An AHP method for identifying influential factors on insurance cost

    Directory of Open Access Journals (Sweden)

    Firouzeh Azizi

    2013-09-01

    Full Text Available During the past few years, there have been increasing competitions in insurance firms around the world and most insurance firms try to find appropriate methods to reduce the cost of their products. In this paper, we perform an empirical investigation to find important factors influencing cost management in insurance industry. The proposed study of this paper detects five items including human productivity, economic inflation, competitions within industry, information technology and rate of damage paid to customers, which are effective on four important cost components. The implementation of analytical hierarchy process on ranking four cost components indicate that the amount of damage paid to customers is the most important factor followed by administration expenses, commission and advertisement.

  9. Growth and the growth hormone-insulin like growth factor 1 axis in children with chronic inflammation: current evidence, gaps in knowledge and future directions

    OpenAIRE

    Wong, S. C.; Dobie, R.; Altowati, M A; Werther, G A; Farquharson, C; Ahmed, S. F.

    2016-01-01

    Growth failure is frequently encountered in children with chronic inflammatory conditions like juvenile idiopathic arthritis, inflammatory bowel disease and cystic fibrosis. Delayed puberty and attenuated pubertal growth spurt is often seen during adolescence. The underlying inflammatory state mediated by pro-inflammatory cytokines, prolonged use of glucocorticoid and suboptimal nutrition contribute to growth failure and pubertal abnormalities. These factors can impair growth by their effects...

  10. Association between Social and Demographic Factors with Feeding Methods in

    OpenAIRE

    Maryam Gholamalizadeh; Saeid Doaei; Naser Kalantari; Bahram Rashidkhani

    2013-01-01

    Background: Healthy Nutrition has an important role in childhood. Food habits of a child probably will continue to adulthood and increase the risk of many chronic diseases. Role of parents in child nutrition as a food producer and eating pattern has recognized to most important factor of child nutrition. Recent studies have shown that the methods used by parents to child feeding have an important role in the child’s diet and BMI. This paper aimed to investigate which parents use which types o...

  11. Methods for the estimate of the magnetic axis, the last closed flux surface and the differential shift in an RFP plasma

    Science.gov (United States)

    Boboc, A.; Franz, P.; Murari, A.; Giudicotti, L.; Zilli, E.; Zanca, P.; O'Gorman, M.; Prunty, S.

    2002-07-01

    We present a preliminary investigation of the plasma column displacement in the RFX reversed field pinch (RFP) experiment, carried out with different diagnostics. Determinations of the plasma position have been obtained by a set of external pick-up coils, a multichannel far infrared (FIR) polarimeter and a soft x-ray (SXR) tomographic camera. These diagnostics provide complementary information about the plasma position. In particular, the location of the polarimetric chords allows a direct estimate of the horizontal magnetic axis shift. The analysis of the isoemissivity SXR surfaces also allow investigations of the differential shift of the various magnetic surfaces. A comparison of the results of these three diagnostics is reported, and their agreement is found to be satisfactory and consistent with our expectations.

  12. Methods for the estimate of the magnetic axis, the last closed flux surface and the differential shift in an RFP plasma

    International Nuclear Information System (INIS)

    We present a preliminary investigation of the plasma column displacement in the RFX reversed field pinch (RFP) experiment, carried out with different diagnostics. Determinations of the plasma position have been obtained by a set of external pick-up coils, a multichannel far infrared (FIR) polarimeter and a soft x-ray (SXR) tomographic camera. These diagnostics provide complementary information about the plasma position. In particular, the location of the polarimetric chords allows a direct estimate of the horizontal magnetic axis shift. The analysis of the isoemissivity SXR surfaces also allow investigations of the differential shift of the various magnetic surfaces. A comparison of the results of these three diagnostics is reported, and their agreement is found to be satisfactory and consistent with our expectations. (author)

  13. 基于三轴联动的曲轴连杆颈切点跟踪磨削法研究%Research on Crankshaft Tangential Point Tracking Grinding Method Based on Three-axis

    Institute of Scientific and Technical Information of China (English)

    徐志扬; 黄兴红

    2011-01-01

    通过分析目前的基于两轴联动的曲轴连杆颈切点跟踪磨削法存在的各种不足,提出了基于三轴联动的曲轴连杆颈切点跟踪磨削法,砂轮可以在X轴和Y轴两个方向进行插补;对该磨削法的运动模型进行了研究.结果表明,采用这种磨削方法可以实现磨削点的恒线速度磨削,多次实验后的数据显示,连杆颈的圆柱度可以达到2μm,表面粗糙度Ra达到0.4μm,为获得较高的曲轴加工精度和表面质量提供了有效的方法.%By analyzing the deficiency of current crankshaft tangential point tracking grinding method based on two-axis, crankshaft tangential point tracking grinding method based on three-axis was proposed. The grinding wheel can move in X and Y axis direction. Their motion models were studied. The results show that this grinding method can achieve constant speed grinding. After experiments, the crankshaft pin can be machined with the cylindricity of 2μm and the surface roughness Ra of 0. 4μm. And it provides an effective method to obtain high machining accuracy and surface quality of the crankshaft pin.

  14. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

    KAUST Repository

    Prest, Emmanuelle I.

    2016-02-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  15. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges.

    Science.gov (United States)

    Prest, Emmanuelle I; Hammes, Frederik; van Loosdrecht, Mark C M; Vrouwenvelder, Johannes S

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  16. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

    Science.gov (United States)

    Prest, Emmanuelle I.; Hammes, Frederik; van Loosdrecht, Mark C. M.; Vrouwenvelder, Johannes S.

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  17. Biological stability of drinking water: controlling factors, methods and challenges

    Directory of Open Access Journals (Sweden)

    Emmanuelle ePrest

    2016-02-01

    Full Text Available Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g. development of opportunistic pathogens, aesthetic (e.g. deterioration of taste, odour, colour or operational (e.g. fouling or biocorrosion of pipes problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors such as (i type and concentration of available organic and inorganic nutrients, (ii type and concentration of residual disinfectant, (iii presence of predators such as protozoa and invertebrates, (iv environmental conditions such as water temperature, and (v spatial location of microorganisms (bulk water, sediment or biofilm. Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i existing knowledge on biological stability controlling factors and (ii how these factors are affected by drinking water production and distribution conditions. In addition, (iii the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discuss how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order to

  18. Stress-dependent phosphorylation of myocardin-related transcription factor A (MRTF-A) by the p38MAPK/MK2 axis

    Science.gov (United States)

    Ronkina, Natalia; Lafera, Juri; Kotlyarov, Alexey; Gaestel, Matthias

    2016-01-01

    Myocardin-related transcription factor A (MRTF-A) is a known actin-regulated transcriptional coactivator of serum response factor (SRF). Stimulation of actin polymerization activates MRTF-A by releasing it from G-actin and thus allowing it to bind to and activate SRF. Here, we compared protein phosphorylation in MK2/3-deficient cells rescued or not by ectopic expression of MK2 in two independent phosphoproteomic approaches using anisomycin-treated MEF cells and LPS-stimulated mouse macrophages, respectively. Two MRTF-A sites, Ser351 (corresponding to Ser312 in human) and Ser371 (Ser333 in human), showed significantly stronger phosphorylation (12-fold and 6-fold increase) in the cells expressing MK2. MRTF-A is phosphorylated at these sites in a stress-, but not in a mitogen-induced manner, and p38MAPK/MK2 catalytic activities are indispensable for this phosphorylation. MK2-mediated phosphorylation of MRTF-A at Ser312 and Ser333 was further confirmed in an in vitro kinase assay and using the phospho-protein kinase-D (PKD)-consensus motif antibody (anti-LXRXXpS/pT), the p38MAPK inhibitor BIRB-796, MK2/3-deficient cells and MRTF-A phospho-site mutants. Unexpectedly, dimerization, subcellular localization and translocation, interaction with actin, SRF or SMAD3 and transactivating potential of MRTF-A seem to be unaffected by manipulating the p38MAPK/MK2-dependent phosphorylations. Hence, MRTF-A is stress-dependently phosphorylated by MK2 at Ser312 and Ser333 with so far undetected functional and physiological consequences. PMID:27492266

  19. Project-Method Fit: Exploring Factors That Influence Agile Method Use

    Science.gov (United States)

    Young, Diana K.

    2013-01-01

    While the productivity and quality implications of agile software development methods (SDMs) have been demonstrated, research concerning the project contexts where their use is most appropriate has yielded less definitive results. Most experts agree that agile SDMs are not suited for all project contexts. Several project and team factors have been…

  20. 基于改进遗传算法的三轴磁场传感器校正方法研究%Research on correction method of three-axis magnetic field sensor based on IGA

    Institute of Scientific and Technical Information of China (English)

    张英堂; 张光; 李志宁; 范红波; 程利军

    2013-01-01

    针对三分量磁场传感器存在三轴非正交性、三轴灵敏度不一致和零点偏移误差,不能满足磁场精确测量的问题,提出了一种基于改进遗传算法的三轴磁场传感器校正方法.建立了实际传感器的测量模型,分析了误差产生的机理,研究了误差校正的方法,设计了基于遗传算法和改进遗传算法的校正参数求解过程,通过仿真实验和实测实验,验证了校正方法的有效性和改进遗传算法的快速性,经校正后的三轴磁场传感器的测量精度得到大大提高.%According to the problem that there are measuring errors in three-axis magnetic field sensor caused by nonorthogonali-ty, different sensitivity and zero-shit, a correction method of three-axis magnetic field sensor based on Improved Genetic Algorithm (IGA) is put forward. The measuring model of actual sensor is built, and analysed the mechanism of errors generating. Studied the method of errors correction, and designed the solving course of correction parameters based on GA and IGA. The validity of correction method and the faster speed of IGA is proved by simulation and measuring experiment. The precision of the three-axis magnetic field sensor is greatly improved after correction.

  1. ANALYSIS OF CLIQUE BY MATRIX FACTORIZATION AND PARTITION METHODS

    Directory of Open Access Journals (Sweden)

    Raghunath Kar

    2011-10-01

    Full Text Available In real life clustering of high dimensional data is a big problem. Tofind out the dense regions from increasing dimensions is one of them.We have already studied the clustering techniques of low dimensionaldata sets like k-means, k-mediod, BIRCH, CLARANS, CURE, DBScan, PAM etc. If a region is dense then it consists with number of data points with a minimum support of input parameter ø other wise itcannot take into clustering. So in this approach we have implementedCLIQUE to find out the clusters from multidimensional data sets. Indimension growth subspace clustering the clustering process start atsingle dimensional subspaces and grows upward to higher dimensionalones. It is a partition method where each dimension divided like a grid structure. In this paper the elimination of redundant objects from the regions by matrix factorization and partition method are implemented. The comparisons between CLIQUES with these two methods are studied. The redundant data point belongs to which region to form a cluster is also studied.

  2. Factors Governing the Accuracy of Subvisible Particle Counting Methods.

    Science.gov (United States)

    Ríos Quiroz, Anacelia; Finkler, Christof; Huwyler, Joerg; Mahler, Hanns-Christian; Schmidt, Roland; Koulov, Atanas V

    2016-07-01

    A number of new techniques for subvisible particle characterization in biotechnological products have emerged in the last decade. Although the pharmaceutical community is actively using them, the current knowledge about the analytical performance of some of these tools is still inadequate to support their routine use in the development of biopharmaceuticals (especially in the case of submicron methods). With the aim of increasing this knowledge and our understanding of the most prominent techniques for subvisible particle characterization, this study reports the results of a systematic evaluation of their accuracy. Our results showed a marked overcounting effect especially for low concentrated samples and particles fragile in nature. Furthermore, we established the relative sample size distribution as the most important contributor to an instrument's performance in accuracy counting. The smaller the representation of a particle size within a solution, the more difficulty the instruments had in providing an accurate count. These findings correlate with a recent study examining the principal factors influencing the precision of the subvisible particle measurements. A more thorough understanding of the capabilities of the different particle characterization methods provided here will help guide the application of these methods and the interpretation of results in subvisible particle characterization studies. PMID:27287519

  3. Fish oil supplementation from 9 to 18 months of age affects the insulin-like growth factor axis in a sex-specific manner in Danish infants.

    Science.gov (United States)

    Damsgaard, Camilla T; Harsløf, Laurine B S; Andersen, Anders D; Hellgren, Lars I; Michaelsen, Kim F; Lauritzen, Lotte

    2016-03-14

    Several studies have investigated the effects of fish oil (FO) on infant growth, but little is known about the effects of FO and sex on insulin-like growth factor-1 (IGF-1), the main regulator of growth in childhood. We explored whether FO v. sunflower oil (SO) supplementation from 9 to 18 months of age affected IGF-1 and its binding protein-3 (IGFBP-3) and whether the potential effects were sex specific. Danish infants (n 115) were randomly allocated to 5 ml/d FO (1·2 g/d n-3 long-chain PUFA (n-3 LCPUFA)) or SO. We measured growth, IGF-1, IGFBP-3 and erythrocyte EPA, a biomarker of n-3 LCPUFA intake and status, at 9 and 18 months. Erythrocyte EPA increased strongly with FO compared with SO (PIGF-1 in the total population, but a sex × group interaction (P=0·02). Baseline-adjusted IGF-1 at 18 months was 11·1 µg/l (95% CI 0·4, 21·8; P=0·04) higher after FO compared with SO supplementation among boys only. The sex × group interaction was borderline significant in the model of IGFBP-3 (P=0·09), with lower IGFBP-3 with FO compared with SO among girls only (P=0·03). The results were supported by sex-specific dose-response associations between changes in erythrocyte EPA and changes in IGF-1 and IGFBP-3 (both PIGF-1 was sex specifically associated with BMI and length. In conclusion, FO compared with SO resulted in higher IGF-1 among boys and lower IGFBP-3 among girls. The potential long-term implications for growth and body composition should be investigated further. PMID:26758502

  4. Certain methodical aspects of hygienic regulation of hazardous factors

    International Nuclear Information System (INIS)

    The problem of hygienic regulation of hazardous radiation and chemical factors is considered. Differences in reliability of some standards for radioactive and chemical substances are determined in experiments on animals (mices, rats). The differences were established for 60Co, sup(89, 90)Sr, 210Pb, 210Po, 226Ra and for 7 chemical substances (corrosive sublimate, lead, methyl mercury, chlorine compounds, strontium, hexamethylenediamine, beryllium). Maximum permissible concentrations of radionuclides are shown to be superfluously over estimated; standards for toxic chemical substances are not strictly substantiated that is dangerous for human beings and environmental objects. Necessity of unique methodological and methodical approaches to hygienic standardization on the base of cost-benefit analysis is emphasized

  5. Optimisation of Sintering Factors of Titanium Foams Using Taguchi Method

    Directory of Open Access Journals (Sweden)

    S. Ahmad

    2010-06-01

    Full Text Available Metal foams have the potential to be used in the production of bipolar plates in Polymer Electron Membrane Fuel Cells (PEMFC. In this paper, pure titanium was used to prepare titanium foam using the slurry method. The electrical conductivity is the most important parameter to be considered in the production of good bipolar plates. To achieve a high conductivity of the titanium foam, the effects of various parameters including temperature, time profile and composition have to be characterised and optimised. This paper reports the use of the Taguchi method in optimising the processing parameters of pure titanium foams. The effects of four sintering factors, namely, composition, sintering temperature, heating rate and soaking time on the electrical conductivity has been studied. The titanium slurry was prepared by mixing titanium alloy powder, polyethylene glycol (PEG, methylcellulose and water. Polyurethane (PU foams were then impregnated into the slurry and later dried at room temperature. These were next sintered in a high temperature vacuum furnace. The various factors were assigned to an L9 orthogonal array. From the Analysis of Variance (ANOVA, the composition of titanium powder has the highest percentage of contribution (24.51 to the electrical conductivity followed by the heating rate (10.29. The optimum electrical conductivity was found to be 1336.227 ± 240.61 S/cm-1 for this titanium foam. It was achieved with a 70% composition of titanium, sintering temperature of 1200oC, a heating rate of 0.5oC/min and 2 hours soaking time. Confirmatory experiments have produced results that lay within the 90% confidence interval.

  6. 通用多轴数控机床误差建模与指令修正方法的研究%Research on General Error Modeling and Instructions Correction Method for Multi-axis CNC Machine Tools

    Institute of Scientific and Technical Information of China (English)

    范晋伟; 王晓峰; 李云

    2013-01-01

    How to improve the machining accuracy of multi-axis CNC machine tools with least investment is the hot spot of todays social research. In order to solve the problem,modifying the instructions of NC machine to improve the accuracy is the most effective method. The multi-axis CNC machine tool was analyzed with multi-body theory. The general error model of multi-axis CNC machine tools was established. Based on these,a thorough study on rotary error was made. Taking C-A type machine tool as example,the in-terative solution method was used to get the precise NC instructions of rotary angle.%  机床已经成为工业领域不可缺少的加工工具,特别是多轴机床的出现改变了传统的加工方式。针对如何提高多轴数控机床的精度展开研究,应用多体理论建立了通用多轴数控机床误差模型,在此基础上,给出了多轴数控机床平移和转动数控精密指令求解方法。并以C-A型五轴数控机床为例,采用迭代的方法求出了回转角的精密指令值。

  7. Preferred axis in cosmology

    CERN Document Server

    Zhao, Wen

    2016-01-01

    The foundation of modern cosmology relies on the so-called cosmological principle which states an homogeneous and isotropic distribution of matter in the universe on large scales. However, recent observations, such as the temperature anisotropy of the cosmic microwave background (CMB) radiation, the motion of galaxies in the universe, the polarization of quasars and the acceleration of the cosmic expansion, indicate preferred directions in the sky. If these directions have a cosmological origin, the cosmological principle would be violated, and modern cosmology should be reconsidered. In this paper, by considering the preferred axis in the CMB parity violation, we find that it coincides with the preferred axes in CMB quadrupole and CMB octopole, and they all align with the direction of the CMB kinematic dipole. In addition, the preferred directions in the velocity flows, quasar alignment, anisotropy of the cosmic acceleration, the handedness of spiral galaxies, and the angular distribution of the fine-structu...

  8. The role of the vascular endothelial growth factor/vascular endothelial growth factor receptors axis mediated angiogenesis in curcumin-loaded nanostructured lipid carriers induced human HepG2 cells apoptosis

    Directory of Open Access Journals (Sweden)

    Fengling Wang

    2015-01-01

    Full Text Available Background: Curcumin (diferuloylmethane, the active constituent of turmeric extract has potent anti-cancer properties have been demonstrated in hepatocellular carcinoma (HCC. However, its underlying molecular mechanism of therapeutic effects remains unclear. Vascular endothelial growth factor (VEGF and its receptors (VEGFRs have crucial roles in tumor angiogenesis. Purpose: The goal of this study was to investigate the role of the VEGF/VEGFRs mediated angiogenesis during the proliferation and apoptosis of human HepG2 hepatoma cell line and the effect of curcumin-loaded nanostructured lipid carriers (Cur-NLC. Materials and Methods: The proliferation of HepG2 cells was determined by methyl thiazolyl tetrazolium after exposure to Cur-NLC and native curcumin. Apoptosis was quantified by flow cytometry with annexin V-fluorescein isothiocyanate and propidium iodide staining. Cellular internalization of Cur-NLC was observed by fluorescent microscope. The level of VEGF was detected by enzyme-linked immunosorbent assay kits. The expression of VEGFRs was quantified by Western blotting. Results: Cur-NLC was more effective in inhibiting the proliferation and enhancing the apoptosis of HepG2 cells than native curcumin. Fluorescent microscope analysis showed that HepG2 cells internalized Cur-NLC more effectively than native curcumin. Furthermore, Cur-NLC down-regulated the level of VEGF and the expression of VEGFR-2, but had a slight effect on VEGFR-1. Conclusion: These results clearly demonstrated that Cur-NLC was more effective in anti-cancer activity than the free form of curcumin. These studies demonstrate for the 1 st time that Cur-NLC exerts an antitumor effect on HepG2 cells by modulating VEGF/VEGFRs signaling pathway.

  9. A reciprocating compressor fault diagnosis method based on piston rod axis orbit%基于活塞杆轴心位置轨迹的往复压缩机故障诊断技术研究

    Institute of Scientific and Technical Information of China (English)

    马晋; 江志农; 高金吉

    2012-01-01

    In this paper, a new method of fault diagnosis based on X and Y direction of the piston rod axis orbit is proposed firstly. The five graphs and six parameters were defined to reflect the operation state of the piston rod. Via this method, the traditional means limitation of only monitoring the single vertical displacement is solved. It has been verified the effectiveness of the piston rod axis orbit method by a set of simulation data and a feult instance. The method can analyze the direction and degree of the reciprocating compressor support ring wear, and provide an early warning of the piston components and piston rod running state. The established theory provides a theoretical basis for early warning and quantifying the fault diagnosis expert system rule by defining feature parameters.%提出了一种基于X方向、y方向的活塞杆轴心位置轨迹(Piston-Rod Axis Orbit)的故障诊断分析新方法,通过定义5种图形和6个特征参数来反映活塞杆的运行状态,解决了常规手段只能单一监测垂直方向位移的问题.通过仿真数据和故障数据分析,验证了活塞杆轴心位置图分析方法可以有效判断往复压缩机整个支承环的磨损方向和磨损程度,对于早期预警活塞组件、活塞杆运行状态十分有效.建立的理论方法可以早期、完整地发现往复压缩机活塞组件的潜在故障,定义的特征参数为早期预警和故障诊断专家系统规则量化提供了理论基础.

  10. Exactly Solvable Hydrogen-like Potentials and Factorization Method

    CERN Document Server

    Rosas-Ortiz, J O

    1998-01-01

    It is introduced a set of factorization energies giving place to a generalization of the Schrödinger and Infeld-Hull factorization for the radial Hydrogen-like Hamiltonian. An algebraic intertwinning technique involving such factorization energies leads us to derive $n$-parametric families of potentials in general almost-isospectral to the Hydrogen-like radial Hamiltonians. The construction of a SUSY partner Hamiltonian using a factorization energy $\\epsilon_l^{(k)}$ greater than the ground state energy of the departure Hamiltonian is explicitely performed.

  11. Comparison of Different Numerical Methods for Quality Factor Calculation of Nano and Micro Photonic Cavities

    DEFF Research Database (Denmark)

    Taghizadeh, Alireza; Mørk, Jesper; Chung, Il-Sug

    2014-01-01

    Four different numerical methods for calculating the quality factor and resonance wavelength of a nano or micro photonic cavity are compared. Good agreement was found for a wide range of quality factors. Advantages and limitations of the different methods are discussed.......Four different numerical methods for calculating the quality factor and resonance wavelength of a nano or micro photonic cavity are compared. Good agreement was found for a wide range of quality factors. Advantages and limitations of the different methods are discussed....

  12. Discussion on the Two Coordinate Axis Perpendicularity Error Measurement Method%两坐标轴垂直度误差测量方法的探讨

    Institute of Scientific and Technical Information of China (English)

    刘震

    2014-01-01

    In cartesian coordinate measurement system, the perpendicular error of two axes will directly affect the measurement results. The paper introduces three methods of perpendicular error measurement and describes the principle of different methods, including the calculation method using coordinate values which is mentioned. In this method, the standard device should not special set, and no need to know the actual error of the standard device.%直角坐标测量系统中,两坐标轴的垂直度误差会直接影响测量结果,文中探讨了三种垂直度测量方法,介绍了各种方法的原理,其中提出的利用坐标值计算方法,对标准器的摆放无特殊要求,且无需知道标准器的实际尺寸。

  13. Area specific stripping factors for AGS. A method for extracting stripping factors from survey data

    Energy Technology Data Exchange (ETDEWEB)

    Aage, H.K.; Korsbech, U. [Technical Univ. of Denmark (Denmark)

    2006-04-15

    In order to use Airborne Gamma-ray Spectrometry (AGS) for contamination mapping, for source search etc. one must to be able to eliminate the contribution to the spectra from natural radioactivity. This in general is done by a stripping technique. The parameters for performing a stripping have until recently been measured by recording gamma spectra at special calibration sites (pads). This may be cumbersome and the parameters may not be correct when used at low gamma energies for environmental spectra. During 2000-2001 DTU tested with success a new technique for Carborne Gamma-ray Spectrometry (CGS) where the spectra from the surveyed area (or from a similar area) were used for calculating the stripping parameters. It was possible to calculate usable stripping ratios for a number of low energy windows - and weak source signals not detectable by other means were discovered with the ASS technique. In this report it is shown that the ASS technique also works for AGS data, and it has been used for recent Danish AGS tests with point sources. (Check of calibration of AGS parameters.) By using the ASS technique with the Boden data (Barents Rescue) an exercise source was detected that has not been detected by any of the teams during the exercise. The ASS technique therefore seems to be better for search for radiation anomalies than any other method known presently. The experiences also tell that although the stripping can be performed correctly at any altitude there is a variation of the stripping parameters with altitude that has not yet been quite understood. However, even with the oddly variations the stripping worked as expected. It was also observed that one might calculate a single common set of usable stripping factors for all altitudes from the entire data set i.e. some average a, b and c values. When those stripping factors were used the stripping technique still worked well. (au)

  14. 胰岛素-胰岛素样生长因子-1轴与结直肠癌%Insulin-Insulin-Like Growth Factor-1 Axis and Colorectal Cancer

    Institute of Scientific and Technical Information of China (English)

    刘蕊

    2011-01-01

    Type 2 diabetes mellitus and colorectal cancer are common chronic diseases.Patients with Type 2 diabetes mellitus have an increased risk of developing colorectal cancer.Foreign epidemiological studies show that hyperinsulinemia in the context of Type 2 diabetes mellitus is potentially associated with an increased risk of developing colorectal cancer.The risk is higher if the patients have been treated with insulin, and there is an increasing risk of cancer with longer duration of insulin treatment.The hyperinsulinemia hypothesis suggests that elevated levels of insulin and free IGF-1 may promote the proliferation and inhibit the apoptosis of colorectal epithelial cell via the insulin-insulin-like growth factor-1 ( IGF-1 ) axis, ultimately resulting in colorectal cancer.Therefore, the role of the insulin-IGF-1 axis is important in the development of colorectal cancer among Type 2 diabetics.In addition, because most of the early symptoms of this disease are not always obvious, all patients with Type 2 diabetes mellitus should choose the appropriate screening modality to effectively prevent or suppress the development of colorectal cancer and get a better quality of life.This review summarizes the epidemiology of insulin therapy among Type 2 diabetes patients with higher colorectal cancer risk and the role of the insulin-IGF-1 axis in the development of colorectal cancer.Furthermore, the present study discusses the application of insulin–IGF-1 axis in targeted therapy for colorectal cancer.This review is intended as a useful reference for the early prevention and targeted therapy of colorectal cancer.%2型糖尿病与结直肠癌均为常见的慢性疾病,并且2型糖尿病患者易并发结直肠癌.国外流行病学发现,2型糖尿病(type 2 diabetes mellitus,T2DM)患者高胰岛素血症与结直肠癌患病风险增加具有潜在相关性,而且长期接受胰岛素治疗的患者可使这种风险加倍,并随着胰岛素治疗年限的增加其患病风

  15. Evolution of hypothalamus-pituitary growth axis among fish, amphibian, birds and mammals

    Directory of Open Access Journals (Sweden)

    Moaeen-Ud-Din M.

    2015-01-01

    Full Text Available Hypothalamus-pituitary growth axis (HP growth axis regulates animal growth and development in pre-natal and post natal life governed by many factors. However, until recently, the evolutionary history of this axis among lineages is not understood. Aim of the present study was to understand the major events in evolution and evolutionary history and trend of HP growth axis. The diversity among Homo sapience, Mus musculus, Rattus norvegicus, Gallus gallus, Danio rerio and Xenopus laevis was determined for genes involved in HP growth axis in current study. Sequences of HP growth axis genes were retrieved from NCBI (http://www.ncbi.nlm.nih.gov/. Nucleotide diversity using Kimura’s two-parameter method; codon-based test of positive selection using the Nei-Gojobori; equality of evolutionary rate with Tajima's relative rate test and phylogenetic history using the RelTime method were estimated in MEGA6. Estimates of the coefficients of evolutionary differentiation based on nucleotides and amino acids substitution patterns of HP growth axis genes showed contrasting evolutionary patterns among the lineages. The results demonstrated that although these genes might have crucial functional roles in each of the species, however, their sequence divergence did not necessarily reflect similar molecular evolution among the species. Codon-based test of positive selection revealed that Human vs Mouse, Chicken vs Rat, Human vs Rat and Mouse vs Rat had similar and higher non synonymous substitutions (P > 0.05. Higher rate of non-synonymous substitutions at similar orthologs level among species indicated a similar positive selection pressure in these species. Results for relative rate test assessed with the chi-squared test showed difference on unique mutations among lineages at synonymous and non synonymous sites except Chicken vs Mouse, Human vs Mouse, Chicken vs Rat, Human vs Rat and Mouse vs Rat. This indicated that the mutagenic process that generates

  16. Pauli equation and the method of supersymmetric factorization

    OpenAIRE

    Ioffe, M. V.; Neelov, A. I.

    2003-01-01

    We consider different variants of factorization of a 2x2 matrix Schroedinger/Pauli operator in two spatial dimensions. They allow to relate its spectrum to the sum of spectra of two scalar Schroedinger operators, in a manner similar to one-dimensional Darboux transformations. We consider both the case when such factorization is reduced to the ordinary 2-dimensional SUSY QM quasifactorization and a more general case which involves covariant derivatives. The admissible classes of electromagneti...

  17. 基于速度阻尼的双轴旋转式激光陀螺捷联惯导标定方法%Calibration method for two-axis indexing RLG-SINS with speed damping

    Institute of Scientific and Technical Information of China (English)

    王彬; 翁海娜; 汪湛清; 张宇飞; 胡小毛

    2014-01-01

    factor error and bias of the quartz accelerometer, laser gyroscope bias) can be estimated on mooring base during 4 h operation in zero-speed damping mode. The estimated error for accelerator bias is less than 2%, and the estimated error for gyroscope bias is less than 8%, meeting the demands of high accuracy inertial navigation, and showing that this method has certain engineering practicability.

  18. Pauli equation and the method of supersymmetric factorization

    CERN Document Server

    Ioffe, M V

    2003-01-01

    We consider different variants of factorization of a 2x2 matrix Schroedinger/Pauli operator in two spatial dimensions. They allow to relate its spectrum to the sum of spectra of two scalar Schroedinger operators, in a manner similar to one-dimensional Darboux transformations. We consider both the case when such factorization is reduced to the ordinary 2-dimensional SUSY QM quasifactorization and a more general case which involves covariant derivatives. The admissible classes of electromagnetic fields are described and some illustrative examples are given.

  19. Pauli equation and the method of supersymmetric factorization

    International Nuclear Information System (INIS)

    We consider different variants of factorization of a 2 x 2 matrix Schroedinger/Pauli operator in two spatial dimensions. They allow us to relate its spectrum to the sum of spectra of two scalar Schroedinger operators, in a manner similar to one-dimensional Darboux transformations. We consider both the case when such factorization is reduced to the ordinary two-dimensional supersymmetric quantum mechanics quasifactorization and a more general case which involves covariant derivatives. The admissible classes of electromagnetic fields are described and some illustrative examples are given

  20. Pauli equation and the method of supersymmetric factorization

    Energy Technology Data Exchange (ETDEWEB)

    Ioffe, M V; Neelov, A I [Department of Theoretical Physics, University of Sankt-Petersburg, 198504 Sankt-Petersburg, Russia (Russian Federation)

    2003-03-14

    We consider different variants of factorization of a 2 x 2 matrix Schroedinger/Pauli operator in two spatial dimensions. They allow us to relate its spectrum to the sum of spectra of two scalar Schroedinger operators, in a manner similar to one-dimensional Darboux transformations. We consider both the case when such factorization is reduced to the ordinary two-dimensional supersymmetric quantum mechanics quasifactorization and a more general case which involves covariant derivatives. The admissible classes of electromagnetic fields are described and some illustrative examples are given.

  1. Modified Trial Division Algorithm Using KNJ-Factorization Method To Factorize RSA Public Key Encryption

    OpenAIRE

    Lal, Nidhi; Singh, Anurag Prakash; Kumar, Shishupal

    2015-01-01

    The security of RSA algorithm depends upon the positive integer N, which is the multiple of two precise large prime numbers. Factorization of such great numbers is a problematic process. There are many algorithms has been implemented in the past years. The offered KNJ -Factorization algorithm contributes a deterministic way to factorize RSA. The algorithm limits the search by only considering the prime values. Subsequently prime numbers are odd numbers accordingly it also requires smaller num...

  2. Comparison of three methods for wind turbine capacity factor estimation.

    Science.gov (United States)

    Ditkovich, Y; Kuperman, A

    2014-01-01

    Three approaches to calculating capacity factor of fixed speed wind turbines are reviewed and compared using a case study. The first "quasiexact" approach utilizes discrete wind raw data (in the histogram form) and manufacturer-provided turbine power curve (also in discrete form) to numerically calculate the capacity factor. On the other hand, the second "analytic" approach employs a continuous probability distribution function, fitted to the wind data as well as continuous turbine power curve, resulting from double polynomial fitting of manufacturer-provided power curve data. The latter approach, while being an approximation, can be solved analytically thus providing a valuable insight into aspects, affecting the capacity factor. Moreover, several other merits of wind turbine performance may be derived based on the analytical approach. The third "approximate" approach, valid in case of Rayleigh winds only, employs a nonlinear approximation of the capacity factor versus average wind speed curve, only requiring rated power and rotor diameter of the turbine. It is shown that the results obtained by employing the three approaches are very close, enforcing the validity of the analytically derived approximations, which may be used for wind turbine performance evaluation. PMID:24587755

  3. Comparison of Three Methods for Wind Turbine Capacity Factor Estimation

    Directory of Open Access Journals (Sweden)

    Y. Ditkovich

    2014-01-01

    Full Text Available Three approaches to calculating capacity factor of fixed speed wind turbines are reviewed and compared using a case study. The first “quasiexact” approach utilizes discrete wind raw data (in the histogram form and manufacturer-provided turbine power curve (also in discrete form to numerically calculate the capacity factor. On the other hand, the second “analytic” approach employs a continuous probability distribution function, fitted to the wind data as well as continuous turbine power curve, resulting from double polynomial fitting of manufacturer-provided power curve data. The latter approach, while being an approximation, can be solved analytically thus providing a valuable insight into aspects, affecting the capacity factor. Moreover, several other merits of wind turbine performance may be derived based on the analytical approach. The third “approximate” approach, valid in case of Rayleigh winds only, employs a nonlinear approximation of the capacity factor versus average wind speed curve, only requiring rated power and rotor diameter of the turbine. It is shown that the results obtained by employing the three approaches are very close, enforcing the validity of the analytically derived approximations, which may be used for wind turbine performance evaluation.

  4. The concept of key success factors: Theory and method

    DEFF Research Database (Denmark)

    Grunert, Klaus G.; Ellegaard, Charlotte

    1992-01-01

    are the value perceived by customers in a business's products, and the costs (relative to competitors) incurred in producing this value. How good a business is in creating customer value at low costs will depend on skills and resources of the company. We therefore define a key success factor as a skill...

  5. A Multi-Fork Z-Axis Quartz Micromachined Gyroscope

    Directory of Open Access Journals (Sweden)

    Aiying Yang

    2013-09-01

    Full Text Available A novel multi-fork z-axis gyroscope is presented in this paper. Different from traditional quartz gyroscopes, the lateral electrodes of the sense beam can be arranged in simple patterns; as a result, the fabrication is simplified. High sensitivity is achieved by the multi-fork design. The working principles are introduced, while the finite element method (FEM is used to simulate the modal and sensitivity. A quartz fork is fabricated, and a prototype is assembled. Impedance testing shows that the drive frequency and sense frequency are similar to the simulations, and the quality factor is approximately 10,000 in air. The scale factor is measured to be 18.134 mV/(°/s and the nonlinearity is 0.40% in a full-scale input range of ±250 °/s.

  6. A multi-fork z-axis quartz micromachined gyroscope.

    Science.gov (United States)

    Feng, Lihui; Zhao, Ke; Sun, Yunan; Cui, Jianmin; Cui, Fang; Yang, Aiying

    2013-01-01

    A novel multi-fork z-axis gyroscope is presented in this paper. Different from traditional quartz gyroscopes, the lateral electrodes of the sense beam can be arranged in simple patterns; as a result, the fabrication is simplified. High sensitivity is achieved by the multi-fork design. The working principles are introduced, while the finite element method (FEM) is used to simulate the modal and sensitivity. A quartz fork is fabricated, and a prototype is assembled. Impedance testing shows that the drive frequency and sense frequency are similar to the simulations, and the quality factor is approximately 10,000 in air. The scale factor is measured to be 18.134 mV/(°/s) and the nonlinearity is 0.40% in a full-scale input range of ±250 °/s.

  7. Exercise and the Hypothalamo-Pituitary-Adrenal Axis.

    Science.gov (United States)

    Duclos, Martine; Tabarin, Antoine

    2016-01-01

    Exercise represents a potent physiological stimulus upon the hypothalamo-pituitary adrenal (HPA) axis. Two major factors modulate the HPA axis response to exercise: intensity and duration. Endurance training per se does not induce permanent hypercortisolism as endurance-trained subjects have similar biological markers of HPA axis activity in resting condition as healthy untrained men. However, during a challenge of the HPA axis, endurance-trained subjects demonstrate an adaptation of the HPA axis activity to repeated exercise resulting from decreased tissular sensitivity to glucocorticoids. A great diversity of other mechanisms is involved in this adaptation, acting potentially at all levels in the cascade and leading to the biological effects of cortisol. PMID:27348531

  8. SU-E-J-96: Multi-Axis Dose Accumulation of Noninvasive Image-Guided Breast Brachytherapy Through Biomechanical Modeling of Tissue Deformation Using the Finite Element Method

    Energy Technology Data Exchange (ETDEWEB)

    Rivard, MJ [Tufts University School of Medicine, Boston, MA (United States); Ghadyani, HR [SUNY Farmingdale State College, Farmingdale, NY (United States); Bastien, AD; Lutz, NN [Univeristy Massachusetts Lowell, Lowell, MA (United States); Hepel, JT [Rhode Island Hospital, Providence, RI (United States)

    2015-06-15

    Purpose: Noninvasive image-guided breast brachytherapy delivers conformal HDR Ir-192 brachytherapy treatments with the breast compressed, and treated in the cranial-caudal and medial-lateral directions. This technique subjects breast tissue to extreme deformations not observed for other disease sites. Given that, commercially-available software for deformable image registration cannot accurately co-register image sets obtained in these two states, a finite element analysis based on a biomechanical model was developed to deform dose distributions for each compression circumstance for dose summation. Methods: The model assumed the breast was under planar stress with values of 30 kPa for Young’s modulus and 0.3 for Poisson’s ratio. Dose distributions from round and skin-dose optimized applicators in cranial-caudal and medial-lateral compressions were deformed using 0.1 cm planar resolution. Dose distributions, skin doses, and dose-volume histograms were generated. Results were examined as a function of breast thickness, applicator size, target size, and offset distance from the center. Results: Over the range of examined thicknesses, target size increased several millimeters as compression thickness decreased. This trend increased with increasing offset distances. Applicator size minimally affected target coverage, until applicator size was less than the compressed target size. In all cases, with an applicator larger or equal to the compressed target size, > 90% of the target covered by > 90% of the prescription dose. In all cases, dose coverage became less uniform as offset distance increased and average dose increased. This effect was more pronounced for smaller target-applicator combinations. Conclusions: The model exhibited skin dose trends that matched MC-generated benchmarking results and clinical measurements within 2% over a similar range of breast thicknesses and target sizes. The model provided quantitative insight on dosimetric treatment variables over

  9. A deep matrix factorization method for learning attribute representations

    OpenAIRE

    Trigeorgis, George; Bousmalis, Konstantinos; Zafeiriou, Stefanos; Schuller, Bjoern W.

    2015-01-01

    Semi-Non-negative Matrix Factorization is a technique that learns a low-dimensional representation of a dataset that lends itself to a clustering interpretation. It is possible that the mapping between this new representation and our original data matrix contains rather complex hierarchical information with implicit lower-level hidden attributes, that classical one level clustering methodologies can not interpret. In this work we propose a novel model, Deep Semi-NMF, that is able to learn suc...

  10. Mining big data using parsimonious factor and shrinkage methods

    OpenAIRE

    Kim, Hyun Hak; Swanson, Norman

    2013-01-01

    A number of recent studies in the economics literature have focused on the usefulness of factor models in the context of prediction using "big data". In this paper, our over-arching question is whether such "big data" are useful for modelling low frequency macroeconomic variables such as unemployment, inflation and GDP. In particular, we analyze the predictive benefits associated with the use dimension reducing independent component analysis (ICA) and sparse principal component analysis (SPCA...

  11. METHOD FOR DETERMINING THE MAXIMUM ARRANGEMENT FACTOR OF FOOTWEAR PARTS

    Directory of Open Access Journals (Sweden)

    DRIŞCU Mariana

    2014-05-01

    Full Text Available By classic methodology, designing footwear is a very complex and laborious activity. That is because classic methodology requires many graphic executions using manual means, which consume a lot of the producer’s time. Moreover, the results of this classical methodology may contain many inaccuracies with the most unpleasant consequences for the footwear producer. Thus, the costumer that buys a footwear product by taking into consideration the characteristics written on the product (size, width can notice after a period that the product has flaws because of the inadequate design. In order to avoid this kind of situations, the strictest scientific criteria must be followed when one designs a footwear product. The decisive step in this way has been made some time ago, when, as a result of powerful technical development and massive implementation of electronical calculus systems and informatics, This paper presents a product software for determining all possible arrangements of a footwear product’s reference points, in order to automatically acquire the maximum arrangement factor. The user multiplies the pattern in order to find the economic arrangement for the reference points. In this purpose, the user must probe few arrangement variants, in the translation and rotate-translation system. The same process is used in establishing the arrangement factor for the two points of reference of the designed footwear product. After probing several variants of arrangement in the translation and rotation and translation systems, the maximum arrangement factors are chosen. This allows the user to estimate the material wastes.

  12. Method for processing ENDF/B photon form factor data

    International Nuclear Information System (INIS)

    A method is described for processing ENDF/B photon data to generate group-to-group scattering matrices. The method has these salient features: 1. It is tailored toward treating the full energy and angular detail with which the cross sections are represented in ENDF/B; 2. It is simple to program; 3. It closely parallels a treatment developed for producing multigroup neutron matrices; 4. The time required to execute the method on a computer varies linearly with the number of energy groups as opposed to double numerical integration schemes which tend to vary as the square of the number of groups

  13. ACCURATE MEASUREMENT OF ROTA-RY MACHINE AXIS CENTER TRACE

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Four methods aiming at measuring rotary machine axis center trace are discussed in detail.The comparative analysis is made on some aspects such as measurement accuracy, on-machine characteristics, feasibility, practical operation convenience and the integrity of measurement information.In order to simplify measurement, the axis profile error is ignored in traditional condition, while the measurement accuracy will be reduced.The 3-point method that the axis profile error is firstly separated has better real time character, at the same time, not only the axis motion error but also the axis profile error can be measured.All of those information can be used to diagnose the fault origin.The analysis result is proved to be correct by the experiment.

  14. SMED METHOD ANALYSIS AS A FACTOR SUPPORTING ENTERPRISE MANAGEMENT

    OpenAIRE

    Joanna Nowakowska-Grunt; Robert Sa³ek

    2010-01-01

    Methods of supporting production processes have the significant effect to the improvement in the effectiveness of company management systems, which in more and more competitive and globalized environment is aspiring to the excellence of functioning, of guaranteeing the appropriate quality and the cost cutting and the lead time. SMED method, of which with primary task there is a minimization of times of rearming production machines, it is possible to find application also in other environment ...

  15. Axis-I comorbidity is linked to prospective instability of diagnoses within eating disorders

    OpenAIRE

    Milos, Gabriella F; Baur, Volker; Muehlebach, Sabina; Spindler, Anja

    2013-01-01

    BACKGROUND: Eating disorders (ED) are classified into Anorexia Nervosa, Bulimia Nervosa, and eating disorder not otherwise specified. Prospectively, the diagnostic instability within ED is high, but it is not clear which factors may account for this instability. So far, there is no evidence of whether psychiatric comorbidity may play a role in ED diagnostic crossover. We sought to determine possible influences of comorbidities of axis I and II on diagnostic crossover within ED. METHODS:...

  16. Multi-Axis Accelerometer Calibration System

    Science.gov (United States)

    Finley, Tom; Parker, Peter

    2010-01-01

    A low-cost, portable, and simplified system has been developed that is suitable for in-situ calibration and/or evaluation of multi-axis inertial measurement instruments. This system overcomes facility restrictions and maintains or improves the calibration quality for users of accelerometer-based instruments with applications in avionics, experimental wind tunnel research, and force balance calibration applications. The apparatus quickly and easily positions a multi-axis accelerometer system into a precisely known orientation suitable for in-situ quality checks and calibration. In addition, the system incorporates powerful and sophisticated statistical methods, known as response surface methodology and statistical quality control. These methods improve calibration quality, reduce calibration time, and allow for increased calibration frequency, which enables the monitoring of instrument stability over time.

  17. A survey on critical factors influencing new advertisement methods

    OpenAIRE

    Naser Azad; Seyed Fovad Zarifi; Somayeh Hozori; Shahram Hashemi

    2013-01-01

    Soft drink beverages are important part of many people’s foods and many prefer soft drink to water when they have dinner. Therefore, this business model can be considered as the longest lasting sector for many years and there has been not much change in these products. However, new methods of advertisement play important role for increasing market share. In this paper, we study the impact of new methods of advertisement in product development. The proposed study of this paper designs a questi...

  18. Harnessing Tidal Energy Using Vertical Axis Tidal Turbine

    Directory of Open Access Journals (Sweden)

    Syed Shah Khalid

    2013-01-01

    Full Text Available An overview of the current design practices in the field of Renewable Energy (RE is presented; also paper delineates the background to the development of unique and novel techniques for power generation using the kinetic energy of tidal streams and other marine currents. Also this study focuses only on vertical axis tidal turbine. Tidal stream devices have been developed as an alternative method of extracting the energy from the tides. This form of tidal power technology poses less threat to the environment and does not face the same limiting factors associated with tidal barrage schemes, therefore making it a more feasible method of electricity production. Large companies are taking interest in this new source of power. There is a rush to research and work with this new energy source. Marine scientists are looking into how much these will affect the environment, while engineers are developing turbines that are harmless for the environment. In addition, the progression of technological advancements tracing several decades of R & D efforts on vertical axis turbines is highlighted.

  19. Gonadal steroid hormones and the hypothalamo-pituitary-adrenal axis.

    Science.gov (United States)

    Handa, Robert J; Weiser, Michael J

    2014-04-01

    The hypothalamo-pituitary-adrenal (HPA) axis represents a complex neuroendocrine feedback loop controlling the secretion of adrenal glucocorticoid hormones. Central to its function is the paraventricular nucleus of the hypothalamus (PVN) where neurons expressing corticotropin releasing factor reside. These HPA motor neurons are a primary site of integration leading to graded endocrine responses to physical and psychological stressors. An important regulatory factor that must be considered, prior to generating an appropriate response is the animal's reproductive status. Thus, PVN neurons express androgen and estrogen receptors and receive input from sites that also express these receptors. Consequently, changes in reproduction and gonadal steroid levels modulate the stress response and this underlies sex differences in HPA axis function. This review examines the make up of the HPA axis and hypothalamo-pituitary-gonadal (HPG) axis and the interactions between the two that should be considered when exploring normal and pathological responses to environmental stressors. PMID:24246855

  20. Landscape, ecological and factor zoogeography (methods, approaches, implementation

    Directory of Open Access Journals (Sweden)

    Ravkin Yury Solomonovich

    2012-12-01

    Full Text Available The realization and development of the ideas of A.P.Kuzyakin in the field of landscape zoogeography are considered. It was showed that the methods of collecting and processing results had been changed for recent 50 years significantly towards the rise of reliability and resolution of the collected information as well as the profoundness of its analysis. The recomendations of A.P.Kuzyakin dealing with the optimization of labor expenditures for investigations in accordance with with the necessary and sufficient precision influenced positively the process of the solution of the raised problem. Comparing with the prospects of the direction outlined by A.P.Kuzyakin, greater detailing and ordering were noted, the attention to the analytical part of an investigation increased significantly, particularly the use of up-to-date methods of processing and visualisation of results as well as their theoretical interpretation.

  1. Comparison of box-air-mass-factors and radiances for Multiple-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS geometries calculated from different UV/visible radiative transfer models

    Directory of Open Access Journals (Sweden)

    T. Wagner

    2007-01-01

    Full Text Available The results of a comparison exercise of radiative transfer models (RTM of various international research groups for Multiple AXis Differential Optical Absorption Spectroscopy (MAX-DOAS viewing geometry are presented. Besides the assessment of the agreement between the different models, a second focus of the comparison was the systematic investigation of the sensitivity of the MAX-DOAS technique under various viewing geometries and aerosol conditions. In contrast to previous comparison exercises, box-air-mass-factors (box-AMFs for different atmospheric height layers were modelled, which describe the sensitivity of the measurements as a function of altitude. In addition, radiances were calculated allowing the identification of potential errors, which might be overlooked if only AMFs are compared. Accurate modelling of radiances is also a prerequisite for the correct interpretation of satellite observations, for which the received radiance can strongly vary across the large ground pixels, and might be also important for the retrieval of aerosol properties as a future application of MAX-DOAS. The comparison exercises included different wavelengths and atmospheric scenarios (with and without aerosols. The strong and systematic influence of aerosol scattering indicates that from MAX-DOAS observations also information on atmospheric aerosols can be retrieved. During the various iterations of the exercises, the results from all models showed a substantial convergence, and the final data sets agreed for most cases within about 5%. Larger deviations were found for cases with low atmospheric optical depth, for which the photon path lengths along the line of sight of the instrument can become very large. The differences occurred between models including full spherical geometry and those using only plane parallel approximation indicating that the correct treatment of the Earth's sphericity becomes indispensable. The modelled box-AMFs constitute an

  2. Optimisation of Sintering Factors of Titanium Foams Using Taguchi Method

    OpenAIRE

    Ahmad, S.; Muhamad, N; J. Sahari; K. R. Jamaludin

    2010-01-01

    Metal foams have the potential to be used in the production of bipolar plates in Polymer Electron Membrane Fuel Cells (PEMFC). In this paper, pure titanium was used to prepare titanium foam using the slurry method. The electrical conductivity is the most important parameter to be considered in the production of good bipolar plates. To achieve a high conductivity of the titanium foam, the effects of various parameters including temperature, time profile and composition have to be characterised...

  3. Determination of correction factor ksat for recombination losses in ionization chambers using dual-voltage method

    International Nuclear Information System (INIS)

    A review is presented of determining the saturation correction factor ksat of ionization chambers using a dual-voltage method. Basic relations are listed for the calculation of the correction factor for continuous, pulsed, and pulsed swept radiation, and the methods are presented of solving the relations. The computer code, graphs and tables are listed for determination of the saturation factor on the basis of measurements. The feasibility of the method for practical measurements is discussed. (author). 3 figs., 2 tabs., 10 refs

  4. Unified MOSFET Short Channel Factor Using Variational Method

    Institute of Scientific and Technical Information of China (English)

    陈文松; 田立林; 李志坚

    2000-01-01

    A new natural gate length scale for MOSFET's is presented using Variational Method. Comparison of the short channel effects is conducted for the uniform channel doping bulk MOSFET, intrinsic channel doping bulk MOSFET, SOI MOSFET and double gated MOSFET. And the results are verified by the 2D numerical simulation. Taken all the 2-D effects on front gate dielectric, back gate dielectric and silicon film into account, the data validity of electrical equivalent oxide thickness is investigated by this model, as shows that it is valid only when the gate dielectric constant is relatively small.

  5. Equilibrium calculations for helical axis stellarators

    International Nuclear Information System (INIS)

    An average method based on a vacuum flux coordinate system is presented. This average method permits the study of helical axis stellarators with toroidally dominated shifts. An ordering is introduced, and to lowest order the toroidally averaged equilibrium equations are reduced to a Grad-Shafranov equation. Also, to lowest order, a Poisson-type equation is obtained for the toroidally varying corrections to the equilibium. By including these corrections, systems that are toroidally dominated, but with significant helical distortion to the equilibrium, may be studied. Numerical solutions of the average method equations are shown to agree well with three-dimensional calculations

  6. Slip and Slide Method of Factoring Trinomials with Integer Coefficients over the Integers

    Science.gov (United States)

    Donnell, William A.

    2012-01-01

    In intermediate and college algebra courses there are a number of methods for factoring quadratic trinomials with integer coefficients over the integers. Some of these methods have been given names, such as trial and error, reversing FOIL, AC method, middle term splitting method and slip and slide method. The purpose of this article is to discuss…

  7. Distortion definition and correction in off-axis systems

    Science.gov (United States)

    Da Deppo, Vania; Simioni, Emanuele; Naletto, Giampiero; Cremonese, Gabriele

    2015-09-01

    Off-axis optical configurations are becoming more and more used in a variety of applications, in particular they are the most preferred solution for cameras devoted to Solar System planets and small bodies (i.e. asteroids and comets) study. Off-axis designs, being devoid of central obstruction, are able to guarantee better PSF and MTF performance, and thus higher contrast imaging capabilities with respect to classical on-axis designs. In particular they are suitable for observing extended targets with intrinsic low contrast features, or scenes where a high dynamical signal range is present. Classical distortion theory is able to well describe the performance of the on-axis systems, but it has to be adapted for the off-axis case. A proper way to deal with off-axis distortion definition is thus needed together with dedicated techniques to accurately measure and hence remove the distortion effects present in the acquired images. In this paper, a review of the distortion definition for off-axis systems will be given. In particular the method adopted by the authors to deal with the distortion related issues (definition, measure, removal) in some off-axis instruments will be described in detail.

  8. Dynamic Compensation for Two-Axis Robot Wrist Force Sensors

    OpenAIRE

    Junqing Ma; Aiguo Song; Dongcheng Pan

    2013-01-01

    To improve the dynamic characteristic of two-axis force sensors, a dynamic compensation method is proposed. The two-axis force sensor system is assumed to be a first-order system. The operation frequency of the system is expanded by a digital filter with backward difference network. To filter high-frequency noises, a low-pass filter is added after the dynamic compensation network. To avoid overcompensation, parameters of the proposed dynamic compensation method are defined by trial and error....

  9. Vertical axis wind turbine airfoil

    Science.gov (United States)

    Krivcov, Vladimir; Krivospitski, Vladimir; Maksimov, Vasili; Halstead, Richard; Grahov, Jurij Vasiljevich

    2012-12-18

    A vertical axis wind turbine airfoil is described. The wind turbine airfoil can include a leading edge, a trailing edge, an upper curved surface, a lower curved surface, and a centerline running between the upper surface and the lower surface and from the leading edge to the trailing edge. The airfoil can be configured so that the distance between the centerline and the upper surface is the same as the distance between the centerline and the lower surface at all points along the length of the airfoil. A plurality of such airfoils can be included in a vertical axis wind turbine. These airfoils can be vertically disposed and can rotate about a vertical axis.

  10. Smartamine M and MetaSmart supplementation during the peripartal period alter hepatic expression of gene networks in 1-carbon metabolism, inflammation, oxidative stress, and the growth hormone-insulin-like growth factor 1 axis pathways.

    Science.gov (United States)

    Osorio, J S; Ji, P; Drackley, J K; Luchini, D; Loor, J J

    2014-12-01

    Peripartal cows likely require greater amounts of Met not only at the tissue and cell level for methylation reactions but also for milk protein synthesis after calving. Thirty-nine Holstein cows were fed throughout the peripartal period (-21 d to 30 d in milk) a basal control (CON) diet (n=14) with no Met supplementation, CON plus MetaSmart (MS; Adisseo Inc., Antony, France; n=12), or CON plus Smartamine M (SM; Adisseo Inc.; n=13). The Met supplements were adjusted daily and top-dressed over the total mixed ration at a rate of 0.19 or 0.07% (dry matter) of feed for MS or SM. Liver tissue was collected on -10, 7, and 21 d for transcriptome profiling of genes associated with Met and glutathione metabolism as well as components of the inflammation, oxidative stress, growth hormone/insulin-like growth factor-1 axis, and DNA methylation pathways. Data were analyzed using PROC MIXED of SAS (SAS Institute Inc., Cary, NC) with the preplanned contrasts CON versus SM + MS and SM versus MS. The S-adenosylhomocysteine hydrolase (SAHH) gene was the most abundant among all genes evaluated, with overall greater expression in Met-supplemented cows than CON, and in SM than MS. Expression of Met adenosyltransferase 1A (MAT1A) was greater in Met-supplemented cows than CON by 21 d postpartum. A greater overall expression of 5-methyltetrahydrofolate-homocysteine methyltransferase (MTR) occurred in Met-supplemented cows than CON. In contrast, the expression of glutathione synthase (GSS); glutamate-cysteine ligase, catalytic subunit (GCLC); and superoxide dismutase 1, cytosolic (SOD1) was lower in Met-supplemented cows than CON. A greater overall expression of nuclear factor of kappa light polypeptide gene enhancer in B-cells 1 (NFKB1) and greater upregulation of haptoglobin (HP) on d 7 occurred in Met-supplemented cows than CON. Expression of DNA cytosine-5-methyltransferase 3 alpha (DNMT3A) was greater but expression of DNMT1 was lower in Met-supplemented cows than CON. The response

  11. Gut Microbiota-brain Axis

    Science.gov (United States)

    Wang, Hong-Xing; Wang, Yu-Ping

    2016-01-01

    Objective: To systematically review the updated information about the gut microbiota-brain axis. Data Sources: All articles about gut microbiota-brain axis published up to July 18, 2016, were identified through a literature search on PubMed, ScienceDirect, and Web of Science, with the keywords of “gut microbiota”, “gut-brain axis”, and “neuroscience”. Study Selection: All relevant articles on gut microbiota and gut-brain axis were included and carefully reviewed, with no limitation of study design. Results: It is well-recognized that gut microbiota affects the brain's physiological, behavioral, and cognitive functions although its precise mechanism has not yet been fully understood. Gut microbiota-brain axis may include gut microbiota and their metabolic products, enteric nervous system, sympathetic and parasympathetic branches within the autonomic nervous system, neural-immune system, neuroendocrine system, and central nervous system. Moreover, there may be five communication routes between gut microbiota and brain, including the gut-brain's neural network, neuroendocrine-hypothalamic-pituitary-adrenal axis, gut immune system, some neurotransmitters and neural regulators synthesized by gut bacteria, and barrier paths including intestinal mucosal barrier and blood-brain barrier. The microbiome is used to define the composition and functional characteristics of gut microbiota, and metagenomics is an appropriate technique to characterize gut microbiota. Conclusions: Gut microbiota-brain axis refers to a bidirectional information network between the gut microbiota and the brain, which may provide a new way to protect the brain in the near future. PMID:27647198

  12. A Method to Determine the Slip Factor of Centrifugal Pumps through Experiment

    Science.gov (United States)

    Zhang, Yu-Liang; Zhu, Zu-Chao; Dou, Hua-Shu; Cui, Bao-Ling; Li, Yi; Xiao, Jun-Jian

    2015-04-01

    In this paper, a method to determine the slip factor of centrifugal impellers is proposed based on the experimental result of the external performance of centrifugal pumps. This proposed method is superior to the conventional experimental method, which needs not to measure the flow parameters at impeller outlet. The results show that the present method can be used to obtain the slip factor at offdesign condition in a wide range of flow rate besides at the design point.

  13. Circular Interpolation Algorithms of 5-Axis Simultaneous CNC System

    Institute of Scientific and Technical Information of China (English)

    ZHENG Kuijing; SHANG Bo

    2006-01-01

    Spatial circular arc can be machined conveniently by a 5-axis NC machine tool. Based on the data sampling method, circular interpolation in two-dimensional plane is discussed briefly. The key is to solve the problem of circular center expressed in the workpiece coordinate system by means of the transformation matrix. Circular interpolation in three-dimensional space is analyzed in detail. The method of undetermined coefficient is used to solve the center of the spatial circle and the method of coordinate transformation is used to transform the spatial circle into the XY_plane. Circular arc in three-dimensional space can be machined by the positional 5-axis machining and the conical surface can be machined by the continuous 5-axis machining. The velocity control is presented to avoid the feedrate fluctuation. The interpolation algorithms are tested by a simulation example and the interpolation algorithms are proved feasible. The algorithms are applied to the 5-axis CNC system software.

  14. Toward a Unified Theory of the Relationship between Training Methods and Factors of Cognitive Ability

    Science.gov (United States)

    Carter, Shani D.

    2008-01-01

    The paper proposes a theory that trainees have varying ability levels across different factors of cognitive ability, and that these abilities are used in varying levels by different training methods. The paper reviews characteristics of training methods and matches these characteristics to different factors of cognitive ability. The paper proposes…

  15. An effective method to accurately calculate the phase space factors for $\\beta^- \\beta^-$ decay

    CERN Document Server

    Neacsu, Andrei

    2015-01-01

    Accurate calculations of the electron phase space factors are necessary for reliable predictions of double-beta decay rates, and for the analysis of the associated electron angular and energy distributions. We present an effective method to calculate these phase space factors that takes into account the distorted Coulomb field of the daughter nucleus, yet allows one to easily calculate the phase space factors with good accuracy relative to the most exact methods available in the recent literature.

  16. Fano factor in gaseous argon measured by the proportional scintillation method

    International Nuclear Information System (INIS)

    It is found that the apparent Fano factor in argon obtained by using 5.90 keV X-rays with the proportional scintillation method depends on the gas pressure and that the true Fano factor can be obtained by extrapolating the linear relation between the apparent Fano factor and the reciprocal of the gas pressure. The Fano factor thus obtained gives good agreement, within experimental errors, with the value recently obtained by using a gridded ionization chamber. (orig.)

  17. Off-axis illumination direct-to-digital holography

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Clarence E.; Price, Jeffery R.; Voelkl, Edgar; Hanson, Gregory R.

    2004-06-08

    Systems and methods are described for off-axis illumination direct-to-digital holography. A method of recording an off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis, includes: reflecting a reference beam from a reference mirror at a non-normal angle; reflecting an object beam from an object at an angle with respect to an optical axis defined by a focusing lens; focusing the reference beam and the object beam at a focal plane of a digital recorder to form the off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis; digitally recording the off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis; Fourier analyzing the recorded off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes by transforming axes of the recorded off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes in Fourier space to sit on top of a heterodyne carrier frequency defined as an angle between the reference beam and the object beam; applying a digital filter to cut off signals around an original origin; and then performing an inverse Fourier transform.

  18. Comparison of box-air-mass-factors and radiances for Multiple-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) geometries calculated from different UV/visible radiative transfer models

    OpenAIRE

    Wagner, T.; J. P. Burrows; Deutschmann, T.; Dix, B.; Von Friedeburg, C.; Frieß, U.; F. Hendrick; K.-P. Heue; Irie, H.; H. Iwabuchi; Y. Kanaya; Keller, J.; Mclinden, C. A.; Oetjen, H.; Palazzi, E.

    2007-01-01

    International audience The results of a comparison exercise of radiative transfer models (RTM) of various international research groups for Multiple AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) viewing geometry are presented. Besides the assessment of the agreement between the different models, a second focus of the comparison was the systematic investigation of the sensitivity of the MAX-DOAS technique under various viewing geometries and aerosol conditions. In contrast to...

  19. [A factor analysis method for contingency table data with unlimited multiple choice questions].

    Science.gov (United States)

    Toyoda, Hideki; Haiden, Reina; Kubo, Saori; Ikehara, Kazuya; Isobe, Yurie

    2016-02-01

    The purpose of this study is to propose a method of factor analysis for analyzing contingency tables developed from the data of unlimited multiple-choice questions. This method assumes that the element of each cell of the contingency table has a binominal distribution and a factor analysis model is applied to the logit of the selection probability. Scree plot and WAIC are used to decide the number of factors, and the standardized residual, the standardized difference between the sample, and the proportion ratio, is used to select items. The proposed method was applied to real product impression research data on advertised chips and energy drinks. Since the results of the analysis showed that this method could be used in conjunction with conventional factor analysis model, and extracted factors were fully interpretable, and suggests the usefulness of the proposed method in the study of psychology using unlimited multiple-choice questions. PMID:26964368

  20. 用进刀量补偿法减小细长轴车削加工误差%Amount of teed compensation method for reducing thin major axis turning error

    Institute of Scientific and Technical Information of China (English)

    刘龙田

    2012-01-01

    首先分析了细长轴车削加工时造成的位移,理论上分析了误差的大小与位移量的关系.然后运用材料力学公式得出切削点位移量与切削力的关系,又根据径向切削力经验公式获得切削力与进刀量的关系.推出了理论进刀量与实际进刀量的关系,提出了用进刀量补偿法减小细长轴车削加工误差的模型。最后通过试验验证了采用进刀量补偿方法,在不改变机床精度的前提下显著提高细长轴的加工精度。%The turning of slender shaft processing caused by displacement is analyzed, theoretical analysis of the error and displacement relationship, then the use of material mechanics formula of cutting point displacement and cutting force, and according to the radial cutting force experiential formulas for cutting force and feed amount relationship, introduced the theoretical amount of feed and the actual amount of feed, with feed forward compensation method to reduce the thin major axis turning error model. The test verifies the feed compensation method, in does not change the machine tool precision significantly improve the accuracy of slender shaft processing.

  1. Dynamic Factor Method of Computing Dynamic Mathematical Model for System Simulation

    Institute of Scientific and Technical Information of China (English)

    老大中; 吴娟; 杨策; 蒋滋康

    2003-01-01

    The computational methods of a typical dynamic mathematical model that can describe the differential element and the inertial element for the system simulation are researched. The stability of numerical solutions of the dynamic mathematical model is researched. By means of theoretical analysis, the error formulas, the error sign criteria and the error relationship criterion of the implicit Euler method and the trapezoidal method are given, the dynamic factor affecting the computational accuracy has been found, the formula and the methods of computing the dynamic factor are given. The computational accuracy of the dynamic mathematical model like this can be improved by use of the dynamic factor.

  2. The Post Processing Developing of Five-axis CNC Machine

    Directory of Open Access Journals (Sweden)

    Anjiang Cai

    2012-07-01

    Full Text Available In this study, we have a research of the methods of the special post processing program developing of Five-axis CNC machine DMC 70ev. On the basis of analysis about the characteristics of MILLPLUS IT V530 CNumerical control system, special post processor applied to five-axis CNC machining mode based on IMSPost was developed. Special post processing program developed was proved its accuracy and reliability by put it into practice. The research results has important significance for post processing developing of other types of five-axis CNC machines and provides a guideline for the post processing program of other CAD/CAM software.

  3. Measurement and Prediction Method of Compressibility Factor at High Temperature and High Pressure

    OpenAIRE

    Xiaoxun Zhu; Bochao Xu; Zhonghe Han

    2016-01-01

    In order to get the compressibility factor Z of working fluid under different conditions, experimental measurement method of Z under high pressure and high temperature and data mining method were studied in this paper. Experimental measurement method based on real gas state equation and prediction method based on Least Squares Support Vector Machine were proposed. First, an experimental method for measuring Z at high temperature and high pressure was designed; in this method the temperature, ...

  4. CALCULATING THE MOLECULAR INTERNAL ROTATING STERIC FACTOR OF POLYMERS BY THE RADIATION CROSSLINKING METHOD

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wanxi; SUN Jiazhen

    1987-01-01

    In this paper, calculating the molecular internal rotating steric factor of polymers by the radiation crosslinking method is studied and a relationship between the molecular internal rotating steric factor (σ) and crosslinking parameter β is established[1] by taking account of the effect of polymer chain flexibility on β value. σ value of polymer obtained by this method is in agreement with that given with other method.

  5. Qualitative and quantitative methods for human factor analysis and assessment in NPP. Investigations and results

    International Nuclear Information System (INIS)

    We consider here two basic groups of methods for analysis and assessment of the human factor in the NPP area and give some results from performed analyses as well. The human factor is the human interaction with the design equipment, with the working environment and takes into account the human capabilities and limits. In the frame of the qualitative methods for analysis of the human factor are considered concepts and structural methods for classifying of the information, connected with the human factor. Emphasize is given to the HPES method for human factor analysis in NPP. Methods for quantitative assessment of the human reliability are considered. These methods allow assigning of probabilities to the elements of the already structured information about human performance. This part includes overview of classical methods for human reliability assessment (HRA, THERP), and methods taking into account specific information about human capabilities and limits and about the man-machine interface (CHR, HEART, ATHEANA). Quantitative and qualitative results concerning human factor influence in the initiating events occurrences in the Kozloduy NPP are presented. (authors)

  6. Calculation method of fluid and structure interaction in a vertical-axis ticlal current turbine%潮流能水轮机单向流固耦合计算方法

    Institute of Scientific and Technical Information of China (English)

    荆丰梅; 肖钢; 熊志民

    2013-01-01

    Based on ANSYS and CFX software, the calculation method of fluid and structure interaction in a vertical-axis tidal current turbine (VATC) was presented. 2-D CFX fluid calculation results were taken as loads exerted on the water turbine, the correponding stresses at nodes between fluid and structure were exerted on the FE model of the structure, then the strain calculation of the main shaft of the water turbine was completed. By comparison, the numerical calculation results were coincided well with the test ones. Therefore, it was shown that the proposed numerical calculation method is an effective method to transfer the fluid computing results to the structural analysis, and can forecast the trend of the structure response under the small deformation of the blades of the turbine, it is effective to compute and to check the structural strength of a VATC turbine.%基于ANSYS和CFX软件实现了垂直轴潮流能水轮机单向流固耦合瞬态计算.将二维CFX流体计算结果作为水轮机受力,将流体与结构中相对应的节点压力施加到结构有限元模型上,从而完成水轮机工作状态主轴应变计算.将计算结果与实验结果进行对比发现二者吻合较好,说明单向流固耦合方法是将流体计算结果传递到结构分析的有效方法,在潮流能水轮机叶片小变形的条件下能够准确的预报结构响应的趋势,有效的计算垂直轴水轮机的结构强度,对其结构校核起到很好的指导作用.

  7. Localization method of picking point of apple target based on smoothing contour symmetry axis algorithm%基于平滑轮廓对称轴法的苹果目标采摘点定位方法

    Institute of Scientific and Technical Information of China (English)

    王丹丹; 徐越; 宋怀波; 何东健

    2015-01-01

    果实采摘点的精确定位是采摘机器人必须解决的关键问题。鉴于苹果目标具有良好对称性的特点,利用转动惯量所具有的平移、旋转不变性及其在对称轴方向取得极值的特性,提出了一种基于轮廓对称轴法的苹果目标采摘点定位方法。为了解决分割后苹果目标边缘不够平滑而导致定位精度偏低的问题,提出了一种苹果目标轮廓平滑方法。为了验证算法的有效性,对随机选取的20幅无遮挡的单果苹果图像分别利用轮廓平滑和未进行轮廓平滑的算法进行试验,试验结果表明,未进行轮廓平滑算法的平均定位误差为20.678°,而轮廓平滑后算法平均定位误差为4.542°,比未进行轮廓平滑算法平均定位误差降低了78.035%,未进行轮廓平滑算法的平均运行时间为10.2 ms,而轮廓平滑后算法的平均运行时间为7.5 ms,比未进行轮廓平滑算法平均运行时间降低了25.839%,表明平滑轮廓算法可以提高定位精度和运算效率。利用平滑轮廓对称轴算法可以较好地找到苹果目标的对称轴并实现采摘点定位,表明将该方法应用于苹果目标的对称轴提取及采摘点定位是可行的。%The localization of picking points of fruits is one of the key problems for picking robots, and it is the first step of implementation of the picking task for picking robots. In view of a good symmetry of apples, and characteristics of shift, rotation invariance, and reaching the extreme values in symmetry axis direction which moment of inertia possesses, a new method based on a contour symmetry axis was proposed to locate the picking point of apples. In order to solve the problem of low localization accuracy which results from the rough edge of apples after segmentation, a method of smoothing contour algorithm was presented. The steps of the algorithm were as follow, first, the image was transformed from RGB color space into

  8. Vertical axis wind turbine acoustics

    OpenAIRE

    Pearson, Charlie

    2014-01-01

    Increasing awareness of the issues of climate change and sustainable energy use has led to growing levels of interest in small-scale, decentralised power generation. Small-scale wind power has seen significant growth in the last ten years, partly due to the political support for renewable energy and the introduction of Feed In Tariffs, which pay home owners for generating their own electricity. Due to their ability to respond quickly to changing wind conditions, small-scale vertical axis...

  9. Research on identifying the dynamic error model of strapdown gyro on 3-axis turntable

    Institute of Scientific and Technical Information of China (English)

    WANG Hai; REN Shun-qing; WANG Chang-hong

    2005-01-01

    The dynamic errors of gyros are the important error sources of a strapdown inertial navigation system.In order to identify the dynamic error model coefficients accurately, the static erTor model coefficients which lay a foundation for compensating while identifying the dynamic error model are identified in the gravity acceleration fields by using angular position function of the three-axis turntable. The angular acceleration and angular velocity are excited on the input, output and spin axis of the gyros when the outer axis and the middle axis of a threeaxis turntable are in the uniform angular velocity state simultaneously, while the inner axis of the turntable is in different static angular positions. 8 groups of data are sampled when the inner axis is in 8 different angular positions. These data are the function of the middle axis positions and the inner axis positions. For these data, harmonic analysis method is applied two times versus the middle axis positions and inner axis positions respectively so that the dynamic error model coefficients are finally identified through the least square method. In the meantime the optimal angular velocity of the outer axis and the middle axis are selected by computing the determination value of the information matrix.

  10. A comparison of right ventricular volume change during systole obtained using the monoplane Simpson’s method in two-dimensional echocardiographic apical four-chamber view with right ventricular volume change obtained using a prisma model reflecting the systolic long-axis shortening of the right ventricle of the heart: A pilot study

    OpenAIRE

    Loiske, K; Emilsson, K

    2008-01-01

    The right ventricle of the heart has a complex geometry, making it difficult to measure its function and volume. In the present study, right ventricular (RV) volume change during systole in two-dimensional echocardiographic apical four-chamber view was estimated using the monoplane Simpson’s method. Measurements of volume change using the monoplane Simpson’s method were compared with those obtained using a theoretical prisma model, which is believed to reflect RV systolic long-axis shortening...

  11. APPLICATION OF NEWTON'S AND CHEBYSHEV'S METHODS TO PARALLEL FACTORIZATION OF POLYNOMIALS

    Institute of Scientific and Technical Information of China (English)

    Shi-ming Zheng

    2001-01-01

    In this paper it is shown in two different ways that one of the family of parallel iterations to determine all real quadratic factors of polynomials presented in [12] is Newton's method applied to the special equation (1.7) below. Furthermore, we apply Chebyshev's method to (1.7) and obtain a new parallel iteration for factorization of polynomials. Finally, some properties of the parallel iterations are discussed.

  12. Off-Axis Aspheric Surfacing Using Sub-Aperture Tools

    Science.gov (United States)

    Feng, Yunpeng; Qiao, Xiaoyan; Cheng, Haobo; Tam, Hon-Yuen

    2013-10-01

    The off-axis aspheric surface used in modern optical systems widely can obtain nearly perfect quality, realize both small packet-size and low-mass, and avoid the central obscuration. But it is difficult to fabricate because of asymmetry. There are some key technologies during the testing and fabrication of off-axis asphere. In this article, we proposed a method of the best fit sphere based on non-negative minimized removal criterion. And a measured data fitting algorithm was presented to estimate the geometry parameters of off-axis aspheric surface. Then an off-axis mirror was fabricated, and the interferometrically measured data was corrected to eliminate the distortion introduced by null compensator in every run. Finally, the surface error of off-axis mirror reduced to pv = 0.372λ, rms = 0.046λ, the surface roughness reached 0.72 nm. These methods mentioned in the article are suitable for off-axis aspheric optics.

  13. Implementing a quick method of determining output factors for small irregularly shaped electron fields

    International Nuclear Information System (INIS)

    Full text: Electron beam output factors for small irregularly shaped electron beam cutouts are time consuming to determine, requiring accurate measurements. At the Nepean Cancer Care Centre (NCCC), a computer program was written using the sector weighted integration method to compute the output factors. This poster presents the implementation process undertaken. The output factors for small and irregularly shaped electron beam cutouts for 6 and 9 MeV electrons from Varian 21EX and 2100CD linear accelerators were determined using (1) direct measurement with diode detector in water phantom, and (2) computational method based on sector-weighted integration method. The computational algorithm is implemented into a computer program written in Visual Basic. Output factors for circular cutouts with various diameters ranging from 2cm to 6cm were measured using a diode detector. The output factors obtained and the shape of the irregular cutout were inputted into the computer program. The computed output factors were compared with the measured values. The results from the sector-weighted method of calculating output factors for small and irregularly shaped electron beam cutouts were within ±2% of the measured value. The computational method can reduce the amount of time required to determine the output factors without sacrificing the accuracy of electron beam treatment, whilst also making the process simpler. NCCC has adopted the sector-weighted integration method to determine the output factors for small irregularly shaped electron beam cutouts. The computer program developed for this purpose is fully tested and used for clinical cases. Copyright (2001) Australasian College of Physical Scientists and Engineers in Medicine

  14. 三轴飞行仿真转台自适应复合控制方法%Adaptive compound control method for the three-axis flight simulator

    Institute of Scientific and Technical Information of China (English)

    王卫红; 姚志超; 郑连强

    2011-01-01

    针对三轴飞行仿真转台高精确度伺服系统中存在的由于系统模型参数变化,以及外部扰动、摩擦引起的不确定性和非线性,提出基于模型参考自适应的复合控制方案.该方案具有连续自适应、离散自适应和复合控制方法的优势,通过自适应增益的调整及数字前馈控制的引入,能够消除内外部干扰产生的误差,保证系统在宽频带范围内的跟踪性能和控制精确度.实验结果表明,提出的控制方案能够有效地补偿转台系统外部扰动、摩擦引起的非线性和不确定性,拓宽了系统频带,将转台双三指标(频率特性幅值介于-0.264 6~0.257 6 dB之间,相位特性介于-3 ~3°之间)由4.5Hz拓展到10 Hz以上,同时,该方案控制结构清晰、响应速度快、实时性好,控制器设计简单.%As for parameters fluctuating, uncertainties caused by external disturbance and friction, the nonlinearity of the three-axis flight simulator turn table servo system, it is proposed a hybrid adaptive compound control method base on studying the model reference adaptive control ( MRAC). It combines the advantages of adaptive control method and the compound control method, and it can eliminate the model errors by the adjustment of the adaptive gains and the application of the digital feed-forward technology , assuring the dynamic tracking performance and control precision at a long range frequency. The experiment results verified that the proposed control method can broaden the frequency band satisfying amplitude frequency response characterristics -0. 264 6 dB to 0. 257 6 dB and phase frequency response characterristics -3 degree to 3 degree to 10 Hz, and restrain the uncertainties and external disturbance of the whole flight simulator system efficiently. Meanwhile, the control method has the explicit control framework with the properties of fast response, high real-time performance. Furthermore, the whole controller design process is clear

  15. Registration of the rotation axis in X-ray tomography

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yimeng; Yang, Feifei; Hingerl, Ferdinand F.; Xiao, Xianghui; Liu, Yijin; Wu, Ziyu; Benson, Sally M.; Toney, Michael F.; Andrews, Joy C.; Pianetta, Piero A.

    2015-01-01

    There is high demand for efficient, robust and automated routines for tomographic data reduction, particularly for synchrotron data. Registration of the rotation axis in data processing is a critical step affecting the quality of the reconstruction and is not easily implemented with automation. Existing methods for calculating the center of rotation have been reviewed and an improved algorithm to register the rotation axis in tomographic data is presented. The performance of the proposed method is evaluated using synchrotron-based microtomography data on geological samples with and without artificial reduction of the signal-to-noise ratio. The proposed method improves the reconstruction quality by correcting both the tilting error and the translational offset of the rotation axis. The limitation of this promising method is also discussed.

  16. The Mechanical Axis of the First Ray: A Radiographic Assessment in Hallux Abducto Valgus Evaluation.

    Science.gov (United States)

    LaPorta, Guido A; Nasser, Ellianne M; Mulhern, Jennifer L; Malay, D Scot

    2016-01-01

    The present report describes a new method of hallux abducto valgus deformity correction planning using the mechanical axis of the medial column (mechanical axis planning). This method of radiographic evaluation identifies an ideal position for the first metatarsal after correction and is useful regardless of the surgical procedure chosen. We retrospectively reviewed 200 radiographs to identify a "normal" value for the mechanical axis angle. We reviewed 100 radiographs of patients with hallux abducto valgus deformity (deformity group) and 100 radiographs of patients without hallux abducto valgus deformity (control group). The deformity group revealed an M1-M2 anatomic axis angle of 13.5° ± 2.83° and an M1-M2 mechanical axis angle of 11.58° ± 1°. The control group revealed an M1-M2 anatomic axis angle of 7.5° ± 1.76° and an M1-M2 mechanical axis angle of 11.19° ± 0.9°. The differences in the M1-M2 anatomic axis angle and M1-M2 mechanical axis angle were statistically significant between the control and deformity groups. We sought to provide a reliable method for planning hallux abducto valgus deformity correction by aligning the mechanical axis of the medial column and the mechanical axis of the first ray to the "normal" value of 11° to reduce the deformity.

  17. A numerical method for determining the strain rate intensity factor under plane strain conditions

    Science.gov (United States)

    Alexandrov, S.; Kuo, C.-Y.; Jeng, Y.-R.

    2016-07-01

    Using the classical model of rigid perfectly plastic solids, the strain rate intensity factor has been previously introduced as the coefficient of the leading singular term in a series expansion of the equivalent strain rate in the vicinity of maximum friction surfaces. Since then, many strain rate intensity factors have been determined by means of analytical and semi-analytical solutions. However, no attempt has been made to develop a numerical method for calculating the strain rate intensity factor. This paper presents such a method for planar flow. The method is based on the theory of characteristics. First, the strain rate intensity factor is derived in characteristic coordinates. Then, a standard numerical slip-line technique is supplemented with a procedure to calculate the strain rate intensity factor. The distribution of the strain rate intensity factor along the friction surface in compression of a layer between two parallel plates is determined. A high accuracy of this numerical solution for the strain rate intensity factor is confirmed by comparison with an analytic solution. It is shown that the distribution of the strain rate intensity factor is in general discontinuous.

  18. On lifting line analysis of horizontal axis windturbines

    Science.gov (United States)

    Politis, G. K.; Loukakis, T. A.

    A convergent iteration scheme for lifting line performance analysis of horizontal axis windturbines is presented. Lifting line correction factors are introduced and compared with those of Prandtl and Goldstein. Lifting line and strip theory formulations are applied for the calculation of performance for two windturbines. Differences of engineering importance are shown to exist in the prediction of the Power coefficient.

  19. Measurement Axis Searching Model for Terrestrial Laser Scans Registration

    Directory of Open Access Journals (Sweden)

    Shaoxing Hu

    2016-01-01

    Full Text Available Nowadays, terrestrial Lidar scans can cover rather a large area; the point densities are strongly varied because of the line-of-sight measurement principle in potential overlaps with scans taken from different viewpoints. Most of the traditional methods focus on registration algorithm and ignore searching model. Sometimes the traditional methods are directly used to align two point clouds; a large critically unsolved problem of the large biases will be created in areas distant from the overlaps while the local overlaps are often aligned well. So a novel measurement axis searching model (MASM has been proposed in this paper. The method includes four steps: (1 the principal axis fitting, (2 the measurement axis generation, (3 low-high-precision search, and (4 result generation. The principal axis gives an orientation to the point cloud; the search scope is limited by the measurement axis. The point cloud orientation can be adjusted gradually until the achievement of the global optimum using low- and high-precision search. We perform some experiments with simulated point clouds and real terrestrial laser scans. The results of simulated point clouds have shown the processing steps of our method, and the results of real terrestrial laser scans have shown the sensitivity of the approach with respect to the indoor and outdoor scenes.

  20. Finite Difference Methods for Option Pricing under Lévy Processes: Wiener-Hopf Factorization Approach

    Directory of Open Access Journals (Sweden)

    Oleg Kudryavtsev

    2013-01-01

    factorization identity. Notice that our algorithm has the same complexity as the ones which use the explicit-implicit scheme, with a tridiagonal matrix. However, our method is more accurate. We support the advantage of the new method in terms of accuracy and convergence by using numerical experiments.

  1. An experimental method to determine the electrostatic field enhancement factor of a practical conductor surface

    DEFF Research Database (Denmark)

    McAllister, Iain Wilson; Crichton, George C

    1989-01-01

    A method of determining the field enhancement factor of a practical conductor is presented. The method is developed from a modified theory of discharge onset in a gaseous medium. This modification incorporates the influence of conductor surface roughness. Onset data from an experimental study tha...

  2. A new method for high yield purification of type beta transforming growth factor from human platelets

    NARCIS (Netherlands)

    Eijnden-van Raaij, A.J.M. van den; Koornneef, I.; Zoelen, E.J.J. van

    1988-01-01

    A new method was developed for the purification of type beta transforming growth factor from human platelets. This method is a three-step procedure including gel filtration, weak cation exchange HPLC and reverse phase HPLC. All steps are carried out at low pH using exclusively volatile acidic buffer

  3. A Stochastic Method for Semileptonic Form Factor Calculations on the Lattice

    CERN Document Server

    Evans, Richard; Collins, Sara

    2009-01-01

    We investigate an alternative to the Sequential Propagator Method used in Lattice QCD calculations of semileptonic form factors. We replace the sequential propagator with a stochastic propagator so that, in principle, all momentum and sink smearing combinations are available with only a single spin-color inversion. Practically, the stochastic noise is significant and must be reduced at the cost of more inversions. We study the behavior of the stochastic noise and compare the computational costs of this stochastic technique and the Sequential Propagator Method. We also present preliminary semileptonic form factor results using the stochastic technique on N_f=2 configurations with a non-perturbatively improved Sheikoleslami-Wohlert action generated by the QCDSF collaboration. At a fixed cost, measured in terms of the number of heavy-quark inversions, the method provides more correlators for the extraction of the form factors at various q^2's than the Sequential Propagator Method. These additional correlators re...

  4. 航空遥感三轴惯性稳定平台双速度环控制%Dual rate-loop control method of three-axis inertially stabilized platform for aerial remote sensing application

    Institute of Scientific and Technical Information of China (English)

    周向阳; 赵强

    2013-01-01

    航空遥感三轴惯性稳定平台用于稳定成像载荷,获取高分辨率的遥感数据。针对惯性稳定平台视轴稳定控制中单速度环对干扰力矩抑制的不足,提出采用以编码器进行数字测速构成速度内环、利用速率陀螺构成速度外环的双速度环复合控制方案,将稳定回路抗内部干扰功能和隔离外界干扰功能分开设计实现,以提高系统稳定精度。分别对单速度环和双速度环对扰动的抑制能力进行了理论分析和对比,并在理论分析基础上,对单速度环和双速度环的扰动抑制能力进行了Matlab仿真分析和实验验证。结果表明:与单速度环相比,双速度环可明显减小质量偏心、摩擦等主要内部干扰以及外部基座低频扰动造成的稳态误差,静基座摇摆伺服稳定角速度RMS值减小了52.3%,静基座调平姿态精度RMS值减小了22.1%,动基座调平姿态精度RMS值减小了37.4%。%Three-axis inertially stabilized platform can be used to stabilize the imaging sensor in airborne high-resolution remote sensing system. In order to overcome the shortcoming of single rate-loop servo control in disturbance rejection, a dual rate-loop control method is presented in which the measuring signals of encoder and rate gyro are respectively employed to constitute the inner rate loop and the outer rate loop. In this way, the functions of rejecting inner disturbance and insulating carrier turbulence are designed respectively. The performances of disturbance rejection on two control methods are analyzed in theory and are validated in Matlab simulation and experiments. The results show that the dual rate-loop control method can improve the precision of control system obviously through reducing the error caused by mass imbalance, friction and low-frequency carrier disturbance, which agree well with the conclusions of theoretical analysis and simulation results. The angular velocity RMS value and the

  5. Statistical methods in psychiatric research, with special reference on factor analysis

    OpenAIRE

    Miettunen, J.

    2004-01-01

    Abstract This interdisciplinary study describes in the first part the frequency with which various statistical research designs and methods are reported in psychiatric journals, and investigates how the use of these methods affect the visibility of the article in the form of received citations. In the second part focus is specifically on factor analysis, and the study presents two applications of this method. Original research articles (N = 448) from four general psychiatric journals ...

  6. Discussion on Scintillation Compensation Method and Background Interference Analysis in Optical-Axis Detection Model%光轴检测模型中背景干扰分析与闪烁补偿方法探讨

    Institute of Scientific and Technical Information of China (English)

    母一宁; 王贺; 李平; 张金瑞

    2013-01-01

    为了增强四象限光电检测模型对大气环境的适应性,在大气信道二次调制的基础上对四象限光电检测模型展开了研究.首先从误差原理的角度,推导大气环境下光轴检测系统中的固有分辨精度与细分精度的关系;接着通过分析四象限光电检测系统在大气环境下受到的外界约束条件,指出信标光的信噪比和光轴偏移量是影响光轴检测系统的两个重要技术参数.在此基础上,提出在大气环境下提高光轴检测系统的固有分辨精度可以降低整个系统对大气信道的敏感度,大气信道对光轴检测的细分影响严重,如果采用较高的固有分辨精度,光轴检测精度依然可以满足激光通信光轴对准的需要.%The four-quadrant photoelectric inspection model is studied on the basis of the second atmospheric channel modulator for enhancing the four-quadrant photoelectric inspection adaptability of the atmospheric channel.Firstly,the conversion relations of natural resolution and division precision are discussed from error theory perspectives for the analysis of the axis detection system.Afterwards,through the analysis of restricted constraint condition of four-quadrant photoelectric inspection system in atmospheric channel,it is found that the signal-to-noise ratio (SNR) of the beacon light and axis offset are two main technical parameters affecting the electro-optical inspection system.Then a concept is presented that enhancing natural resolution optical-axis detection system can lower the sensitivity of the whole system to the atmospheric channel.Finally,the division precision of axis detection is found to be gravely affected by the atmospheric channel.Axis detection can still provide precision for wireless laser communication if the natural resolution of four-quadrant photoelectric inspection is enhanced.

  7. Improvement of Power Flow Calculation with Optimization Factor Based on Current Injection Method

    Directory of Open Access Journals (Sweden)

    Lei Wang

    2014-01-01

    Full Text Available This paper presents an improvement in power flow calculation based on current injection method by introducing optimization factor. In the method proposed by this paper, the PQ buses are represented by current mismatches while the PV buses are represented by power mismatches. It is different from the representations in conventional current injection power flow equations. By using the combined power and current injection mismatches method, the number of the equations required can be decreased to only one for each PV bus. The optimization factor is used to improve the iteration process and to ensure the effectiveness of the improved method proposed when the system is ill-conditioned. To verify the effectiveness of the method, the IEEE test systems are tested by conventional current injection method and the improved method proposed separately. Then the results are compared. The comparisons show that the optimization factor improves the convergence character effectively, especially that when the system is at high loading level and R/X ratio, the iteration number is one or two times less than the conventional current injection method. When the overloading condition of the system is serious, the iteration number in this paper appears 4 times less than the conventional current injection method.

  8. Various methods of numerical estimation of generalized stress intensity factors of bi-material notches

    Directory of Open Access Journals (Sweden)

    Klusák J.

    2009-12-01

    Full Text Available The study of bi-material notches becomes a topical problem as they can model efficiently geometrical or material discontinuities. When assessing crack initiation conditions in the bi-material notches, the generalized stress intensity factors H have to be calculated. Contrary to the determination of the K-factor for a crack in an isotropic homogeneous medium, for the ascertainment of the H-factor there is no procedure incorporated in the calculation systems. The calculation of these fracture parameters requires experience. Direct methods of estimation of H-factors need choosing usually length parameter entering into calculation. On the other hand the method combining the application of the reciprocal theorem (Ψ-integral and FEM does not require entering any length parameter and is capable to extract the near-tip information directly from the far-field deformation.

  9. Evaluation of Factors Affecting Prescribing Behaviors, in Iran Pharmaceutical Market by Econometric Methods

    OpenAIRE

    Tahmasebi, Nima; Kebriaeezadeh, Abbas

    2015-01-01

    Prescribing behavior of physicians affected by many factors. The present study is aimed at discovering the simultaneous effects of the evaluated factors (including: price, promotion and demographic characteristics of physicians) and quantification of these effects. In order to estimate these effects, Fluvoxamine (an antidepressant drug) was selected and the model was figured out by panel data method in econometrics. We found that insurance and advertisement respectively are the most effective...

  10. Development of Methods for the Estimation of Impact of Physical Factors on the Health of Population

    OpenAIRE

    Vasilyev, Andrey; Zabolotskikh, Vlada; Vasilyev, Vladislav

    2013-01-01

    Physical factors (noise, vibration, electromagneticfields, ionized radiation, etc.) may have a negative influence bothon the environment and on the health of population. This studyconsiders the methods and approaches to estimate the impact ofphysical factors on the health of population and environment.The analysis is performed and the approaches are provided toestimate the influence of physical pollutants on the human healthin the Russian Federation. Principles of estimation of thecombined im...

  11. Human Reliability Analysis for Design: Using Reliability Methods for Human Factors Issues

    Energy Technology Data Exchange (ETDEWEB)

    Ronald Laurids Boring

    2010-11-01

    This paper reviews the application of human reliability analysis methods to human factors design issues. An application framework is sketched in which aspects of modeling typically found in human reliability analysis are used in a complementary fashion to the existing human factors phases of design and testing. The paper provides best achievable practices for design, testing, and modeling. Such best achievable practices may be used to evaluate and human system interface in the context of design safety certifications.

  12. Correction factor for real-time determination of wood dust mass concentration by photometric method

    Directory of Open Access Journals (Sweden)

    Ankica Čavlović

    2009-03-01

    Full Text Available Samples of wood dust were collected in the working environment of wood machining processes for the purpose of determining correction factors for measuring mass concentration of wood dust by photometric method. According to the NIOSH 0600 Norm and NIOSH Manual of Analytical Methods for photometric measurement, correction factor must be determined before measuring mass concentration of different types of dust. The correction factor is defined as the ratio of mass concentration obtained by the gravimetric method and mass concentration obtained by the photometric method. The correction factor should be determined because of the influence of particle size distribution, density, particle shape and refractive index on values obtained by the photometric method. The aim of the research was to investigate the possibility of using photometric method for the determination of mass concentration of inhalable fraction of airborne wood dust. Sampling was conducted in several woodworking plants during the machining of wet and dry beech-wood, wet and dry oak-wood, wet fir-wood and particleboard. There is a significant correlation between the results obtained by the photometric method and values obtained by the gravimetric method (R2=0.88 and this is the base for using the photometric method in determining mass concentration of airborne wood dust. According to the results of this research, correction factors must be determined and used for measuring mass concentration of inhalable wood dust during the machining of different wood species and wood with different moisture content. The best corresponding results of photometric and gravimetric methods are obtained for the samples collected during machining of wet fir-wood (k=1. The largest correction factor should be used in determining workers exposure to wood dust during machining of dry oak-wood (k=4.4 and particleboard (k=4.5. Only the results of 8-hour measurements of mass concentration by gravimetric methods can

  13. Fast satellite prediction for four-axis telescopes

    Institute of Scientific and Technical Information of China (English)

    林钦畅

    1996-01-01

    The features of the method are as follows: Adopting an optimum average small arc to four-axis prediction,the azimuth and altitude of the tracking axis need not be adjusted during the same observation procedure.The prediction has been used for three different types of telescopes for many years and all demands of users have been satisfied.In this method,the prediction contents were more than others.Separating the unknowns,the actual equations for operation were concise,and the needed machine time was much less,even for the prediction of multistation.

  14. SEISMIC RANDOM VIBRATION ANALYSIS OF STOCHASTIC STRUCTURES USING RANDOM FACTOR METHOD

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Seismic random vibration analysis of stochastic truss structures is presented. A new method called random factor method is used for dynamic analysis of structures with uncertain parameters, due to variability in their material properties and geometry. Using the random factor method, the natural frequencies and modeshapes of a stochastic structure can be respectively described by the product of two parts, corresponding to the random factors of the structural parameters with uncertainty, and deterministic values of the natural frequencies and modeshapes obtained by conventional finite element analysis. The stochastic truss structure is subjected to stationary or non-stationary random earthquake excitation. Computational expressions for the mean and standard deviation of the mean square displacement and mean square stress are developed by means of the random variable's functional moment method and the algebra synthesis method. An antenna and a truss bridge are used as practical engineering examples to illustrate the application of the random factor method in the seismic response analysis of random structures under stationary or non-stationary random earthquake excitation.

  15. CFD-based method of determining form factor k for different ship types and different drafts

    Science.gov (United States)

    Wang, Jinbao; Yu, Hai; Zhang, Yuefeng; Xiong, Xiaoqing

    2016-07-01

    The value of form factor k at different drafts is important in predicting full-scale total resistance and speed for different types of ships. In the ITTC community, most organizations predict form factor k using a low-speed model test. However, this method is problematic for ships with bulbous bows and transom. In this article, a Computational Fluid Dynamics (CFD)-based method is introduced to obtain k for different type of ships at different drafts, and a comparison is made between the CFD method and the model test. The results show that the CFD method produces reasonable k values. A grid generating method and turbulence model are briefly discussed in the context of obtaining a consistent k using CFD.

  16. Role of Met Axis in Head and Neck Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yiru, E-mail: xuyiru@umich.edu; Fisher, Gary J., E-mail: xuyiru@umich.edu [Department of Dermatology, University of Michigan, Ann Arbor, MI 48109 (United States)

    2013-11-26

    Head and neck cancer is the sixth most common type of cancer worldwide. Despite advances in aggressive multidisciplinary treatments, the 5-year survival rate for this dreadful disease is only 50%, mostly due to high rate of recurrence and early involvement of regional lymph nodes and subsequent metastasis. Understanding the molecular mechanisms responsible for invasion and metastasis is one of the most pressing goals in the field of head and neck cancer. Met, also known as hepatocyte growth factor receptor (HGFR), is a member of the receptor protein tyrosine kinase (RPTK) family. There is compelling evidence that Met axis is dysregulated and plays important roles in tumorigenesis, progression, metastasis, angiogenesis, and drug resistance in head and neck cancer. We describe in this review current understanding of Met axis in head and neck cancer biology and development of therapeutic inhibitors targeting Met axis.

  17. Medical ultrasound imaging method combining minimum variance beamforming and general coherence factor

    Institute of Scientific and Technical Information of China (English)

    WU Wentao; PU Jie; LU Yi

    2012-01-01

    In medical ultrasound imaging field, in order to obtain high resolution and correct the phase errors induced by the velocity in-homogeneity of the tissue, a high-resolution medical ultrasound imaging method combining minimum variance beamforming and general coherence factor was presented. First, the data from the elements is delayed for focusing; then the multi-channel data is used for minimum variance beamforming; at the same time, the data is transformed from array space to beam space to calculate the general coherence factor; in the end, the general coherence factor is used to weight the results of minimum variance beamforming. The medical images are gotten by the imaging system. Experiments based on point object and anechoic cyst object are used to verify the proposed method. The results show the proposed method in the aspects of resolution, contrast and robustness is better than minimum variance beamforming and conventional beamforming.

  18. Qualitative and quantitative methods for human factor analysis and assessment in NPP. Investigations and results

    International Nuclear Information System (INIS)

    A description of the most frequently used approaches for human reliability assesment is given. The relation between different human factor causes for human induced events in Kozloduy NPP during the period 2000 - 2003 is discussed. A comparison between the contribution of the casual factors for events occurrences in Kozloduy NPP and an Japanese NPP is presented. It can be concluded that for both NPPs the most important casual factors are: 1) written procedures and documents; 2) man-machine interface; 3) environmental working conditions; 4) working practice; 5) training and qualification; 6) supervising methods

  19. A New Thermodynamic Calculation Method for Binary Alloys Part II: Exploring the Correction Factor Function

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new method of revising activity values has been derived based on the so called correction factor function for binary alloys with a large difference between two components. The correction factor is a function of physical properties formed by the difference of two components. Its absolute value increases with the enhancement of the difference in the character of components. It can be either positive or negative and the rules for selecting the sign of correction factor have been analyzed. Results are in good agreement with the experimental values.

  20. Finding the Axis of Revolution of an Algebraic Surface of Revolution.

    Science.gov (United States)

    Alcazar, Juan G; Goldman, Ron

    2016-09-01

    We present an algorithm for extracting the axis of revolution from the implicit equation of an algebraic surface of revolution based on three distinct computational methods: factoring the highest order form into quadrics, contracting the tensor of the highest order form, and using univariate resultants and gcds. We compare and contrast the advantages and disadvantages of each of these three techniques and we derive conditions under which each technique is most appropriate. In addition, we provide several necessary conditions for an implicit algebraic equation to represent a surface of revolution. PMID:26561460

  1. 丝胶对Ⅱ型糖尿病大鼠海马生长激素/胰岛素样生长因子-1轴的作用%Effects of sericin on growth hormone/insulin-like growth factor-1 axis of the hippocampus in type 2 diabetes mellitus rat

    Institute of Scientific and Technical Information of China (English)

    和亚强; 王小杰; 苏哲君; 陈志宏

    2013-01-01

    目的:探讨丝胶对Ⅱ型糖尿病大鼠海马生长激素(GH)/胰岛素样生长因子-1(IGF-1)轴的作用.方法:雄性SD大鼠随机分为正常对照组、糖尿病模型组、丝胶治疗组和阳性对照组.2%链脲佐菌素3d连续腹腔注射的方法建立Ⅱ型糖尿病大鼠模型后,丝胶治疗组和阳性对照组大鼠分别给予丝胶和二甲双胍灌胃治疗35 d.ELISA法检测各组大鼠血清GH和IGF-1水平,免疫印迹和RT-PCR法分别检测大鼠海马GH、生长激素受体(GHR)和IGF-1蛋白和mRNA的表达.结果:与正常对照组大鼠比较,糖尿病模型大鼠血清GH水平、海马GH的表达明显升高,血清IGF-1水平、海马GHR和IGF-1的表达明显降低;与糖尿病模型组大鼠比较,丝胶治疗组大鼠血清GH水平、海马GH的表达明显降低,血清IGF-1水平、海马GHR和IGF-1的表达明显升高.结论:丝胶可通过调节糖尿病海马GH/IGF-1轴的异常变化减轻海马损伤.%Objective:To investigate the effects of sericin on growth hormone (GH)/insulin-like growth factor-1 (IGF-1) axis of the hippocampus of type 2 diabetes mellitus rats.Methods:Male SD rats were randomly divided into 4 groups:a normal control group,a diabetes model group,a sericin treatment group and a positive control group.The type 2 rat model was established by peritoneal injection of small dose streptozotocin continuously.Then the rats in the sericin treatment group and positive group were respectively lavaged with sericin and metformin for 35 days.ELISA was used to detect GH and IGF-1 level in the serum of the rats in each group,and Western blotting and RT-PCR to detect GH,growth hormone receptor (GHR),IGF-1 protein and mRNA expression in the hippocampus.Results:Compared with the rats in the normal control group,the GH level in serum and GH expression in the hippocampus of the rats in the diabetes model group increased obviously; IGF-1 level in serum,GHR and IGF-1 expression in the hippocampus decreased obviously

  2. Modeling of gamma-ray energy absorption buildup factors using response surface method

    International Nuclear Information System (INIS)

    Buildup factors are always useful for practical computations in gamma-ray shield design. Generally point kernel method being easier to handle is adopted for shielding calculations. This method models a gamma ray directly at the evaluation point without scattering which is multiplied by buildup factors to obtain the gamma dose rate. The American Nuclear Society Standard Committee working group (ANSI/ANS-6.4.3-1991) has compiled the energy absorption and exposure buildup factors from 1 mean free path to 40 mean free paths as a standard reference data base for a large number of elements including water, air and concrete. Literature study reveals that there is a substantially significant disagreement in the buildup factor data by different approximating formulae. In view of this, it is required to compute or predict the buildup factor for those materials. The buildup factor data have been computed by various codes. Some of the codes are ASFIT (Gopinath and Sakamoto et al, 1971), PALLAS (Takeuchi and Tanaka, 1984) and EGS4 (Nelson et al, 1985). Taylor (1954), Berger (1956), Capo (1958) have fitted Goldstein and Wilkins (1954) data to construct parametric buildup factor formulae. Harimaet et al. (1986) has developed geometric progress fitting formula for the ANSI/ANS-6.4.3 (ANSI, 1991). The energy absorption buildup factor is defined as the photon buildup factor in which the quantity of interest is the absorbed or deposited energy in the shield medium and the detector response function is that of absorption in the material. Geometric progression buildup factor formula was simplified using the new modeling (fitting algorithm) of gamma ray energy absorption buildup factor. Advantage of having the simplification of buildup factor formula provides the easiness of usage of point kernel method based gamma shielding in the sense that analytic expression of collided flux can be easily constructed. Furthermore, that analytical expression of collided flux can be optimized to

  3. Computational Experiment Study on Selection Mechanism of Project Delivery Method Based on Complex Factors

    Directory of Open Access Journals (Sweden)

    Xiang Ding

    2014-01-01

    Full Text Available Project delivery planning is a key stage used by the project owner (or project investor for organizing design, construction, and other operations in a construction project. The main task in this stage is to select an appropriate project delivery method. In order to analyze different factors affecting the PDM selection, this paper establishes a multiagent model mainly to show how project complexity, governance strength, and market environment affect the project owner’s decision on PDM. Experiment results show that project owner usually choose Design-Build method when the project is very complex within a certain range. Besides, this paper points out that Design-Build method will be the prior choice when the potential contractors develop quickly. This paper provides the owners with methods and suggestions in terms of showing how the factors affect PDM selection, and it may improve the project performance.

  4. Model correction factor method for reliability problems involving integrals of non-Gaussian random fields

    DEFF Research Database (Denmark)

    Franchin, P.; Ditlevsen, Ove Dalager; Kiureghian, Armen Der

    2002-01-01

    index for the original problem. This method has application to many civil engineering problems that involve random fields of material properties or loads. An application to reliability analysis of foundation piles illustrates the proposed method. Keywords: Directional simulation on a cone; First order...... are considered to be Gaussian. Conventional FORM analysis yields the linearization point of the idealized limit-state surface. A model correction factor is then introduced to push the idealized limit-state surface onto the actual limit-state surface. A few iterations yield a good approximation of the reliability...... reliability method; Model correction factor method; Nataf field integration; Non-Gaussion random field; Random field integration; Structural reliability; Pile foundation reliability...

  5. Integrals of random fields treated by the model correction factor method

    DEFF Research Database (Denmark)

    Franchin, P.; Ditlevsen, Ove Dalager; Kiureghian, Armen Der

    2002-01-01

    The model correction factor method (MCFM) is used in conjunction with the first-order reliability method (FORM) to solve structural reliability problems involving integrals of non-Gaussian random fields. The approach replaces the limit-state function with an idealized one, in which the integrals ...... index for the original problem. This method has application to many civil engineering problems that involve random fields of material properties or loads. An application to reliability analysis of foundation piles illustrates the proposed method....... are considered to be Gaussian. Conventional FORM analysis yields the linearization point of the idealized limit-state surface. A model correction factor is then introduced to push the idealized limit-state surface onto the actual limit-state surface. A few iterations yield a good approximation of the reliability...

  6. High-order sparse factorization methods for elliptic boundary value problems

    Energy Technology Data Exchange (ETDEWEB)

    Hyman, J.M.; Manteuffel, T.A.

    1984-01-01

    We are interested in solving the sparse linear systems, Av = b, that arise from finite difference or finite element approximations to partial differential equations. May iterative methods require solving an easier approximate equation, Pv = b, on each iteration. This is often called preconditioning or operator splitting (1,2,4,6-9,12-14). The methods we consider factor A approximately into the product of an upper and lower triangular matrix P is identical to LU approx. = A. These methods are called incomplete LU factorization methods and their convergence rate depends on how well P approximates A. We describe some new algorithms to generate accurate LU decompositions based on the continuity of the solution v.

  7. Skp2B overexpression alters a prohibitin-p53 axis and the transcription of PAPP-A, the protease of insulin-like growth factor binding protein 4.

    Directory of Open Access Journals (Sweden)

    Harish Chander

    Full Text Available BACKGROUND: We previously reported that the degradation of prohibitin by the SCF(Skp2B ubiquitin ligase results in a defect in the activity of p53. We also reported that MMTV-Skp2B transgenic mice develop mammary gland tumors that are characterized by an increased proteolytic cleavage of the insulin-like growth factor binding protein 4 (IGFBP-4, an inhibitor of IGF signaling. However, whether a link exists between a defect in p53 activity and proteolysis of IGFBP-4 was not established. METHODS AND RESULTS: We analyzed the levels of pregnancy-associated plasma protein A (PAPP-A, the protease of IGFBP-4, in MMTV-Skp2B transgenic mice and found that PAPP-A levels are elevated. Further, we found a p53 binding site in intron 1 of the PAPP-A gene and that both wild type and mutant p53 bind to this site. However, binding of wild type p53 results in the transcriptional repression of PAPP-A, while binding of mutant p53 results in the transcriptional activation of PAPP-A. Since MMTV-Skp2B mice express wild type p53 and yet show elevated levels of PAPP-A, at first, these observations appeared contradictory. However, further analysis revealed that the defect in p53 activity in Skp2B overexpressing cells does not only abolish the activity of wild type of p53 but actually mimics that of mutant p53. Our results suggest that in absence of prohibitin, the half-life of p53 is increased and like mutant p53, the conformation of p53 is denatured. CONCLUSIONS: These observations revealed a novel function of prohibitin as a chaperone of p53. Further, they suggest that binding of denatured p53 in intron 1 causes an enhancer effect and increases the transcription of PAPP-A. Therefore, these findings indicate that the defect in p53 function and the increased proteolysis of IGFBP-4, we had observed, represent two components of the same pathway, which contributes to the oncogenic function of Skp2B.

  8. APPLICATION OF FUZZY CONTROL METHOD WITH SELF-TUNING FACTOR IN JIGGERS DISCHARGING

    Institute of Scientific and Technical Information of China (English)

    杨洁明; 魏晋宏; 刘素芬

    2000-01-01

    Adopting the strategy of fuzzy control with self-tuning factor within whole universe of discourse, a kind of fuzzy control method for jigger discharging is put forward. This method has many advantages over the conventional PID controller in terms of response speed, stability and robustness. It is effective to restrain the jig bed from over-thick or empty, and the stability of the bed is markedly improved. The good results are obtained in factory tests.

  9. Volume Effects on the Method of Extracting Form Factors at Zero Momentum

    OpenAIRE

    Tiburzi, Brian C.

    2014-01-01

    The Rome method allows one to extract form factors using lattice computations performed strictly at zero momentum. We investigate the size of finite volume effects resulting from this method. As a test case, we focus on the pion charge radius and show how to ascertain the finite volume effect with the aid of chiral perturbation theory. The framework developed can easily be generalized to account for modified infrared physics of other low-energy matrix elements extracted at zero momentum.

  10. A Novel Alignment-Free Method for Comparing Transcription Factor Binding Site Motifs

    OpenAIRE

    Minli Xu; Zhengchang Su

    2010-01-01

    BACKGROUND: Transcription factor binding site (TFBS) motifs can be accurately represented by position frequency matrices (PFM) or other equivalent forms. We often need to compare TFBS motifs using their PFMs in order to search for similar motifs in a motif database, or cluster motifs according to their binding preference. The majority of current methods for motif comparison involve a similarity metric for column-to-column comparison and a method to find the optimal position alignment between ...

  11. Alternating optimization method based on nonnegative matrix factorizations for deep neural networks

    OpenAIRE

    Sakurai, Tetsuya; Imakura, Akira; Inoue, Yuto; Futamura, Yasunori

    2016-01-01

    The backpropagation algorithm for calculating gradients has been widely used in computation of weights for deep neural networks (DNNs). This method requires derivatives of objective functions and has some difficulties finding appropriate parameters such as learning rate. In this paper, we propose a novel approach for computing weight matrices of fully-connected DNNs by using two types of semi-nonnegative matrix factorizations (semi-NMFs). In this method, optimization processes are performed b...

  12. Computer Assisted Mechanical Axis and Kinematic TKA

    Science.gov (United States)

    McEwen, Peter; Mahoharan, Varaguna

    2016-01-01

    Introduction: Total knee arthroplasty (TKA) has traditionally been and largely continues to be aligned mechanically, that being with a neutral coronal plane mechanical tibiofemoral axis and a joint line orientated at 900 to this axis. Femoral component rotation is set by gap balancing or by externally rotating 30 from any of a number femoral reference lines. This produces a rectangular flexion gap and relaxes patellar tracking. Kinematic alignment (KA) is an alternative technique that aims to restore premorbid alignment, joint orientation and ligament tension. The basic premise for this technique is based on evidence that the medial and lateral femoral condyles consistently equate to cylinders of equal or near equal size and that therefore with a fixed radius, cruciate retaining implant, matched distal femoral, posterior femoral and proximal tibial resections, accounting for bone and cartilage already lost will reproduce the premorbid joint line and restore native premorbid kinematics. Femoral rotation is therefore referenced off the prearthritic posterior condylar axis (PCA) that is on average internally rotated to the AP axis. Kinematic alignment therefore has the potential to challenge patellar tracking, increase patellar load and potentially increase patellar complications. Method: Case control study – level of evidence III-2. Between November 2012 and June 2013 the senior author completed 104 consecutive computer assisted (CAS) kinematically aligned total knee arthroplasties (TKA) with a cruciate retaining, fixed bearing, single radius implant. The results of these surgeries were compared with the results of 91 consecutive CAS mechanically aligned TKA done between November 2011 and October 2012 using the same navigation system and implant Implant sizing and positioning as well as gap measurement and ligament balance was done with computer assistance in all cases. Data was collected prospectively and analysed retrospectively. Results: The Oxford Knee Score

  13. Five-axis rough machining for impellers

    Institute of Scientific and Technical Information of China (English)

    Ruolong QI; Weijun LIU; Hongyou BIAN; Lun LI

    2009-01-01

    The most important components used in aero-space, ships, and automobiles are designed with free form surfaces. An impeller is one of the most important components that is difficult to machine because of its twisted blades. Rough machining is recognized as the most crucial procedure influencing machining efficiency and is critical for the finishing process. An integrated rough machining course with detailed algorithms is presented in this paper. An algorithm for determining the minimum distance between two surfaces is applied to estimate the tool size. The space between two blades that will be cleared from the roughcast is divided to generate CC points. The tool axis vector is confirmed based on flank milling using a simple method that could eliminate global interference between the tool and the blades. The result proves that the machining methodology presented in this paper is useful and successful.

  14. A Portable Single Axis Magnetic Gradiometer

    DEFF Research Database (Denmark)

    Merayo, José M.G.; Petersen, Jan Raagaard; Nielsen, Otto V;

    2001-01-01

    not provide vector information about the magnetic field. Secondly, one of the sensors measures the ambient magnetic field and is used to compensate for the main field at both sensors. Several methods have been developed for characterization of the 2 gradiometer, and the calibration of the gradient......The single axis magnetic gradiometer based on two compact detector compensation (CDC) fluxgate ringcore sensors separated 20 cm is described. Despite its high stability and precision better than 1 nT, the calibration procedures are not straightforward. Firstly, the mono-axial measurement does...... measurements is achieved by using a magnetic dipole of strength 2 mAm(2). In a coil facility, the gradient can be determined with an accuracy of 0.3 nT/m(RMS)....

  15. Computing a partial Schur factorization of nonlinear eigenvalue problems using the infinite Arnoldi method

    CERN Document Server

    Jarlebring, Elias; Michiels, Wim

    2012-01-01

    The partial Schur factorization can be used to represent several eigenpairs of a matrix in a numerically robust way. Different adaptions of the Arnoldi method are often used to compute partial Schur factorizations. We propose here a technique to compute a partial Schur factorization of a nonlinear eigenvalue problem (NEP). The technique is inspired by the algorithm in [8], now called the infinite Arnoldi method. The infinite Arnoldi method is a method designed for NEPs, and can be interpreted as Arnoldi's method applied to a linear infinite-dimensional operator, whose reciprocal eigenvalues are the solutions to the NEP. As a first result we show that the invariant pairs of the operator are equivalent to invariant pairs of the NEP. We characterize the structure of the invariant pairs of the operator and show how one can carry out a modification of the infinite Arnoldi method by respecting the structure. This also allows us to naturally add the feature known as locking. We nest this algorithm with an outer iter...

  16. Finite difference methods for option pricing under Lévy processes: Wiener-Hopf factorization approach.

    Science.gov (United States)

    Kudryavtsev, Oleg

    2013-01-01

    In the paper, we consider the problem of pricing options in wide classes of Lévy processes. We propose a general approach to the numerical methods based on a finite difference approximation for the generalized Black-Scholes equation. The goal of the paper is to incorporate the Wiener-Hopf factorization into finite difference methods for pricing options in Lévy models with jumps. The method is applicable for pricing barrier and American options. The pricing problem is reduced to the sequence of linear algebraic systems with a dense Toeplitz matrix; then the Wiener-Hopf factorization method is applied. We give an important probabilistic interpretation based on the infinitely divisible distributions theory to the Laurent operators in the correspondent factorization identity. Notice that our algorithm has the same complexity as the ones which use the explicit-implicit scheme, with a tridiagonal matrix. However, our method is more accurate. We support the advantage of the new method in terms of accuracy and convergence by using numerical experiments. PMID:24489518

  17. Human factors analysis and design methods for nuclear waste retrieval systems. Human factors design methodology and integration plan

    Energy Technology Data Exchange (ETDEWEB)

    Casey, S.M.

    1980-06-01

    The purpose of this document is to provide an overview of the recommended activities and methods to be employed by a team of human factors engineers during the development of a nuclear waste retrieval system. This system, as it is presently conceptualized, is intended to be used for the removal of storage canisters (each canister containing a spent fuel rod assembly) located in an underground salt bed depository. This document, and the others in this series, have been developed for the purpose of implementing human factors engineering principles during the design and construction of the retrieval system facilities and equipment. The methodology presented has been structured around a basic systems development effort involving preliminary development, equipment development, personnel subsystem development, and operational test and evaluation. Within each of these phases, the recommended activities of the human engineering team have been stated, along with descriptions of the human factors engineering design techniques applicable to the specific design issues. Explicit examples of how the techniques might be used in the analysis of human tasks and equipment required in the removal of spent fuel canisters have been provided. Only those techniques having possible relevance to the design of the waste retrieval system have been reviewed. This document is intended to provide the framework for integrating human engineering with the rest of the system development effort. The activities and methodologies reviewed in this document have been discussed in the general order in which they will occur, although the time frame (the total duration of the development program in years and months) in which they should be performed has not been discussed.

  18. Human factors analysis and design methods for nuclear waste retrieval systems. Human factors design methodology and integration plan

    International Nuclear Information System (INIS)

    The purpose of this document is to provide an overview of the recommended activities and methods to be employed by a team of human factors engineers during the development of a nuclear waste retrieval system. This system, as it is presently conceptualized, is intended to be used for the removal of storage canisters (each canister containing a spent fuel rod assembly) located in an underground salt bed depository. This document, and the others in this series, have been developed for the purpose of implementing human factors engineering principles during the design and construction of the retrieval system facilities and equipment. The methodology presented has been structured around a basic systems development effort involving preliminary development, equipment development, personnel subsystem development, and operational test and evaluation. Within each of these phases, the recommended activities of the human engineering team have been stated, along with descriptions of the human factors engineering design techniques applicable to the specific design issues. Explicit examples of how the techniques might be used in the analysis of human tasks and equipment required in the removal of spent fuel canisters have been provided. Only those techniques having possible relevance to the design of the waste retrieval system have been reviewed. This document is intended to provide the framework for integrating human engineering with the rest of the system development effort. The activities and methodologies reviewed in this document have been discussed in the general order in which they will occur, although the time frame (the total duration of the development program in years and months) in which they should be performed has not been discussed

  19. A novel method of evaluating large mode area fiber design by brightness factor

    Institute of Scientific and Technical Information of China (English)

    张海涛; 陈丹; 任海翠; 闫平; 巩马理

    2015-01-01

    A novel evaluation term and a more reasonable criterion which is described by a new parameter of brightness factor for active large mode area fiber design are presented. The brightness factor evaluation method is based on the transverse mode competition mechanism in fiber lasers and amplifiers. Brightness factor can be seen as a description of fiber general property since it can represent the output laser brightness of the fiber laser system and its ability to resist nonlinear effect. A core-doped active large pitch fiber with a core diameter of 190 µm and a mode-field diameter of 180 µm is designed by this method, and the designed fiber allows the effective single-mode operation.

  20. Ionospheric eclipse factor method (IEFM) for determining the ionospheric delay using GPS data

    Institute of Scientific and Technical Information of China (English)

    YUAN Yunbin; OU Jikun

    2004-01-01

    By establishing the ionospheric eclipse factor (IEF) λ of the ionospheric pierce point (IPP) and its ionospheric influence factor (IFF) λ, and combining λ, λ with t of IPP, a new method of modeling high-precision ionospheric delay using GPS data-ionospheric eclipse factor method (IEFM)-is presented in this paper. The IEFM can effectively select the proper ionospheric models to model the total electron content (TEC) with different changes corresponding to annual, seasonal and diurnal variations. Initial experimental results show that the correction precision of ionospheric delay modeled by the IEFM seems to be close to that of using L3 GPS observations to directly correct the corresponding ionospheric delay.

  1. AxiSEM: Exploiting structural complexity for efficient wave propagation across the scales

    Science.gov (United States)

    Nissen-Meyer, Tarje; van Driel, Martin; Leng, Kuangdai; Stähler, Simon; Krischer, Lion; Hosseini, Kasra

    2016-04-01

    Our open-source seismic modeling method AxiSEM (www.axisem.info) is presented a backbone for numerous further extensions, including accurate and efficient wave propagation in 3D Earth models, a database mode (www.instaseis.net), local domains, hybrid methods, and waveform sensitivity kernels for tomography. Our general mantra is to enable wave propagation across the observable frequency spectrum in a most efficient manner by adapting the methodology directly to the level of structural complexity, in the vein of Occam's razor. The basic AxiSEM approach relies upon axisymmetric (including spherically symmetric) models, thereby satisfying a large fraction of observable data. The benefit of this method stems from the resultant dimensional collapse to two numerical dimensions, whereby the third azimuthal dimension is tackled analytically. For high-frequency wave propagation, this leads to 3-4 orders of magnitude speedup in computational cost compared to 3D domain discretizations. AxiSEM is highly scalable anywhere between laptops and supercomputers, and includes novel, optimized implementations of viscoelasticity and anisotropy. We present benchmarks, data comparisons, a range of unique applications from inner-core anisotropy to noise modeling and lowermost mantle structures. 1D structures are exploited by instaseis, a methodology to extract full, broadband and accurate waveforms instantaneously from wavefield databases computed with AxiSEM. A webservice built on instaseis ("syngine") has been launched at IRIS (see abstract EGU2016-8190) to generate on-demand synthetics up to 1Hz for prominent Earth models. 3D structures are tackled by our recent extension AxiSEM3D: We expand the wavefield in the azimuthal dimension in Fourier series, leading to a drastic computational cost speedup compared to classic 3D methods (up to a factor of 100), especially in the high-frequency regime. We will show benchmarks for typical global tomographic models and sketch our approach to

  2. Factors influencing HPAM solution viscosity prepared by produced water using orthogonal method

    Institute of Scientific and Technical Information of China (English)

    康万利; 王志伟; 周阳; 孟令伟; 刘述忍; 白宝君

    2008-01-01

    The effect of temperature and metal ion components on the viscosity of HPAM solution was studied by means of orthogonal method.Five factors and 4 levels were considered for the orthogonal design.The five factors included temperature,contents of Na+,Mg2+,Ca2+ and S2-,and the four levels mainly considered the level of produced water components in main oilfields in China.The experiment results show that temperature is the most important factor to control HPAM solution viscosity prepared by produced water.The effect of ions was in order of Na+>S2->Mg2+>Ca2+.The mechanism of each factor influencing viscosity was also discussed.Based on the actual condition of Nanyang oilfield,the desulfurization was used to improve the solution viscosity,and satisfactory result was obtained.

  3. Implementation of a method for calculating output factors in air for irregular fields

    Energy Technology Data Exchange (ETDEWEB)

    Suero Rodrigo, M. A.; Marques Frguela, E.

    2011-07-01

    The concept of output factor in air (Sc) was introduced to characterize the variation of the incident photon fluence per unit monitor with different settings of the collimator. The objective of this work is the implementation of the method proposed by Zhu et al. (2004) to calculate both as FCSc Sc and verification with the measurements performed in mini-mannequin.

  4. Linear Ordinary Differential Equations with Constant Coefficients. Revisiting the Impulsive Response Method Using Factorization

    Science.gov (United States)

    Camporesi, Roberto

    2011-01-01

    We present an approach to the impulsive response method for solving linear constant-coefficient ordinary differential equations based on the factorization of the differential operator. The approach is elementary, we only assume a basic knowledge of calculus and linear algebra. In particular, we avoid the use of distribution theory, as well as of…

  5. Methods of extracting electron-positron enhancement factors from experimental ACAR data

    International Nuclear Information System (INIS)

    Methods of extracting the full shape of the electron-positron momentum density from experimental angular correlation of positron annihilation radiation curves are discussed. The proposed analysis of experimental data allows more reliable verification of the form of electron-positron enhancement factors near the Fermi surface in simple metals. (author). 14 refs, 2 figs

  6. The Accounting Methods of the Local Government Department Output by Factor Analysis

    OpenAIRE

    Haoyuan Zhong; Guangming Deng

    2014-01-01

    In this paper, using the 2011 national economic accounting data of the provinces, we evaluated the government department performance by factor analysis. And then calculated the local government department's total output taking advantage of the labor production efficiency. And the labor production efficiency of government department concludes the performance information. Which will improved the method of accounting government department's output by cost.

  7. Empirically derived dietary patterns: interpretability and construct validity according to different factor rotation methods

    Directory of Open Access Journals (Sweden)

    Michelle Alessandra de Castro

    2015-02-01

    Full Text Available This study aimed to investigate the effects of factor rotation methods on interpretability and construct validity of dietary patterns derived in a representative sample of 1,102 Brazilian adults. Dietary patterns were derived from exploratory factor analysis. Orthogonal (varimax and oblique rotations (promax, direct oblimin were applied. Confirmatory factor analysis assessed construct validity of the dietary patterns derived according to two factor loading cut-offs (≥ |0.20| and ≥ |0.25|. Goodness-of-fit indexes assessed the model fit. Differences in composition and in interpretability of the first pattern were observed between varimax and promax/oblimin at cut-off ≥ |0.20|. At cut-off ≥ |0.25|, these differences were no longer observed. None of the patterns derived at cut-off ≥ |0.20| showed acceptable model fit. At cut-off ≥ |0.25|, the promax rotation produced the best model fit. The effects of factor rotation on dietary patterns differed according to the factor loading cut-off used in exploratory factor analysis.

  8. Principles of the prolactin/vasoinhibin axis.

    Science.gov (United States)

    Triebel, Jakob; Bertsch, Thomas; Bollheimer, Cornelius; Rios-Barrera, Daniel; Pearce, Christy F; Hüfner, Michael; Martínez de la Escalera, Gonzalo; Clapp, Carmen

    2015-11-15

    The hormonal family of vasoinhibins, which derive from the anterior pituitary hormone prolactin, are known for their inhibiting effects on blood vessel growth, vasopermeability, and vasodilation. As pleiotropic hormones, vasoinhibins act in multiple target organs and tissues. The generation, secretion, and regulation of vasoinhibins are embedded into the organizational principle of an axis, which integrates the hypothalamus, the pituitary, and the target tissue microenvironment. This axis is designated as the prolactin/vasoinhibin axis. Disturbances of the prolactin/vasoinhibin axis are associated with the pathogenesis of retinal and cardiac diseases and with diseases occurring during pregnancy. New phylogenetical, physiological, and clinical implications are discussed.

  9. An improved method using factor division algorithm for reducing the order of linear dynamical system

    Indian Academy of Sciences (India)

    SHARAD KUMAR TIWARI; GAGANDEEP KAUR

    2016-06-01

    An improved method is proposed to determine the reduced order model of large scale linear time invariant system. The dominant poles of the low order system are calculated by clustering method. The selection of pole to the cluster point is based on the contributions of each pole in redefining time moment and redefiningMarkov parameters. The coefficients of the numerator polynomial for reduced model are obtained using a factor division algorithm. This method is computationally efficient and keeps up the stability and input output characteristic of the original arrangement

  10. HUMAN ERROR QUANTIFICATION USING PERFORMANCE SHAPING FACTORS IN THE SPAR-H METHOD

    Energy Technology Data Exchange (ETDEWEB)

    Harold S. Blackman; David I. Gertman; Ronald L. Boring

    2008-09-01

    This paper describes a cognitively based human reliability analysis (HRA) quantification technique for estimating the human error probabilities (HEPs) associated with operator and crew actions at nuclear power plants. The method described here, Standardized Plant Analysis Risk-Human Reliability Analysis (SPAR-H) method, was developed to aid in characterizing and quantifying human performance at nuclear power plants. The intent was to develop a defensible method that would consider all factors that may influence performance. In the SPAR-H approach, calculation of HEP rates is especially straightforward, starting with pre-defined nominal error rates for cognitive vs. action-oriented tasks, and incorporating performance shaping factor multipliers upon those nominal error rates.

  11. Statistical Approach for Predicting Factors of Mood Method for Object Oriented

    Directory of Open Access Journals (Sweden)

    Firas Ajil Jassim

    2013-01-01

    Full Text Available Object oriented design is becoming more popular in software development and object oriented design metrics which is an essential part of software environment. The main goal in this paper is to predict factors of MOOD method for OO using a statistical approach. Therefore, linear regression model is used to find the relationship between factors of MOOD method and their influences on OO software measurements. Fortunately, through this process a prediction could be made for the line of code (LOC, number of classes (NOC, number of methods (NOM, and number of attributes (NOA. These measurements permit designers to access the software early in process, making changes that will reduce complexity and improve the continuing capability of the design.

  12. Research on pattern recognition for marine steam turbine rotor axis orbit

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yan; YANG Zhi-da; XIA Hong

    2003-01-01

    The structure,function and recognition method of an axis orbit auto-recognizing system are presented in this paper.In order to make the best use of information of format and dynamic characteristics of marine steam turbine axis orbit,the structure and functions or neural network are applied to this system,which can be used to auto-recognize axis orbit of the system turbine rotor using BP neural network.

  13. Transcriptional regulatory dynamics of the hypothalamic-pituitary-gonadal axis and its peripheral pathways as impacted by the 3-beta HSD inhibitor Trilostane in zebrafish (Danio rerio)

    Science.gov (United States)

    To identify transcription factors (TFs), members of hypothalamic-pituitary- gonadal axis (HPG-axis), TF networks and signaling pathways underlying generalized effects of 3-beta hydroxysteroid dehydrogenase (HSD3B) inhibition, reproductively mature zebrafish (Danio rerio) were exp...

  14. A Review of Adult Obesity Prevalence, Trends, Risk Factors, and Epidemiologic Methods in Kuwait

    Directory of Open Access Journals (Sweden)

    Stalo Karageorgi

    2013-01-01

    Full Text Available Objective. Kuwait is among the countries with the highest obesity rates worldwide; however, little is known about the state of obesity epidemiology research in Kuwait. In this paper, we therefore review the findings and methodology of studies on the prevalence, trends and risk factors of obesity in Kuwait. Methods. The PubMed database was searched using the keyword combination: obesity and adults and Kuwait. Out of 111 articles, 39 remained after abstract review, and 18 were selected after full-text review. Results. The studies were all cross-sectional and published in the last fifteen years (1997–2012. The sample size ranged from 177 to 38,611 individuals. Only 30% of studies used random sampling. The prevalence (BMI ≥ 30 in studies with a nationally representative sample ranged from 24% to 48% overall and in adults >50 years was greater than 52%. Rates were significantly higher in women than those in men. Studies that examined trends showed an increase in obesity prevalence between 1980 and 2009. Multiple risk factors including sociocultural factors were investigated in the studies; however, factors were only crudely assessed. Conclusion. There is a need for future studies, particularly surveillance surveys and prospective cohort studies utilizing advanced methods, to monitor trends and to comprehensively assess the factors contributing to the obesity epidemic in Kuwait.

  15. A novel alignment-free method for comparing transcription factor binding site motifs.

    Directory of Open Access Journals (Sweden)

    Minli Xu

    Full Text Available BACKGROUND: Transcription factor binding site (TFBS motifs can be accurately represented by position frequency matrices (PFM or other equivalent forms. We often need to compare TFBS motifs using their PFMs in order to search for similar motifs in a motif database, or cluster motifs according to their binding preference. The majority of current methods for motif comparison involve a similarity metric for column-to-column comparison and a method to find the optimal position alignment between the two compared motifs. In some applications, alignment-free methods might be preferred; however, few such methods with high accuracy have been described. METHODOLOGY/PRINCIPAL FINDINGS: Here we describe a novel alignment-free method for quantifying the similarity of motifs using their PFMs by converting PFMs into k-mer vectors. The motifs could then be compared by measuring the similarity among their corresponding k-mer vectors. CONCLUSIONS/SIGNIFICANCE: We demonstrate that our method in general achieves similar performance or outperforms the existing methods for clustering motifs according to their binding preference and identifying similar motifs of transcription factors of the same family.

  16. A Novel Alignment-Free Method for Comparing Transcription Factor Binding Site Motifs

    Science.gov (United States)

    Xu, Minli; Su, Zhengchang

    2010-01-01

    Background Transcription factor binding site (TFBS) motifs can be accurately represented by position frequency matrices (PFM) or other equivalent forms. We often need to compare TFBS motifs using their PFMs in order to search for similar motifs in a motif database, or cluster motifs according to their binding preference. The majority of current methods for motif comparison involve a similarity metric for column-to-column comparison and a method to find the optimal position alignment between the two compared motifs. In some applications, alignment-free methods might be preferred; however, few such methods with high accuracy have been described. Methodology/Principal Findings Here we describe a novel alignment-free method for quantifying the similarity of motifs using their PFMs by converting PFMs into k-mer vectors. The motifs could then be compared by measuring the similarity among their corresponding k-mer vectors. Conclusions/Significance We demonstrate that our method in general achieves similar performance or outperforms the existing methods for clustering motifs according to their binding preference and identifying similar motifs of transcription factors of the same family. PMID:20098703

  17. Determination of small-field correction factors for cylindrical ionization chambers using a semiempirical method

    Science.gov (United States)

    Park, Kwangwoo; Bak, Jino; Park, Sungho; Choi, Wonhoon; Park, Suk Won

    2016-02-01

    A semiempirical method based on the averaging effect of the sensitive volumes of different air-filled ionization chambers (ICs) was employed to approximate the correction factors for beam quality produced from the difference in the sizes of the reference field and small fields. We measured the output factors using several cylindrical ICs and calculated the correction factors using a mathematical method similar to deconvolution; in the method, we modeled the variable and inhomogeneous energy fluence function within the chamber cavity. The parameters of the modeled function and the correction factors were determined by solving a developed system of equations as well as on the basis of the measurement data and the geometry of the chambers. Further, Monte Carlo (MC) computations were performed using the Monaco® treatment planning system to validate the proposed method. The determined correction factors (k{{Q\\text{msr}},Q}{{f\\text{smf}}, {{f}\\text{ref}}} ) were comparable to the values derived from the MC computations performed using Monaco®. For example, for a 6 MV photon beam and a field size of 1  ×  1 cm2, k{{Q\\text{msr}},Q}{{f\\text{smf}}, {{f}\\text{ref}}} was calculated to be 1.125 for a PTW 31010 chamber and 1.022 for a PTW 31016 chamber. On the other hand, the k{{Q\\text{msr}},Q}{{f\\text{smf}}, {{f}\\text{ref}}} values determined from the MC computations were 1.121 and 1.031, respectively; the difference between the proposed method and the MC computation is less than 2%. In addition, we determined the k{{Q\\text{msr}},Q}{{f\\text{smf}}, {{f}\\text{ref}}} values for PTW 30013, PTW 31010, PTW 31016, IBA FC23-C, and IBA CC13 chambers as well. We devised a method for determining k{{Q\\text{msr}},Q}{{f\\text{smf}}, {{f}\\text{ref}}} from both the measurement of the output factors and model-based mathematical computation. The proposed method can be useful in case the MC simulation would not be applicable for the clinical settings.

  18. Identifying Critical Factors in the Eco-Efficiency of Remanufacturing Based on the Fuzzy DEMATEL Method

    Directory of Open Access Journals (Sweden)

    Qianwang Deng

    2015-11-01

    Full Text Available Remanufacturing can bring considerable economic and environmental benefits such as cost saving, conservation of energy and resources, and reduction of emissions. With the increasing awareness of sustainable manufacturing, remanufacturing gradually becomes the research priority. Most studies concentrate on the analysis of influencing factors, or the evaluation of the economic and environmental performance in remanufacturing, while little effort has been devoted to investigating the critical factors influencing the eco-efficiency of remanufacturing. Considering the current development of the remanufacturing industry in China, this paper proposes a set of factors influencing the eco-efficiency of remanufacturing and then utilizes a fuzzy Decision Making Trial and Evaluation Laboratory (DEMATEL method to establish relation matrixes reflecting the interdependent relationships among these factors. Finally, the contributions of each factor to eco-efficiency and mutual influence values among them are obtained, and critical factors in eco-efficiency of remanufacturing are identified. The results of the present work can provide theoretical supports for the government to make appropriate policies to improve the eco-efficiency of remanufacturing.

  19. Genetic and epigenetic studies of diabetes and diabetic nephropathy with focus on the IGF-IGFBP axis

    OpenAIRE

    Gu, Tianwei

    2014-01-01

    Diabetes and diabetic nephropathy (DN) are complex diseases reflecting a complex interplay between genetic and non-genetic factors. The insulin-like growth factor (IGF) - IGF binding protein (IGFBP) axis plays an important role in the development of diabetes and DN. Recent reports have demonstrated that genetic polymorphisms in this axis are associated with diabetes and DN. However, the information of epigenetic study is very limited. In this study, we selected four genes from this axis inclu...

  20. Factoring

    OpenAIRE

    Lenstra, Arjen K.

    1994-01-01

    Factoring, finding a non-trivial factorization of a composite positive integer, is believed to be a hard problem. How hard we think it is, however, changes almost on a daily basis. Predicting how hard factoring will be in the future, an important issue for cryptographic applications of composite numbers, is therefore a challenging task. The author presents a brief survey of general purpose integer factoring algorithms and their implementations

  1. Formation factor logging in-situ by electrical methods. Background and methodology

    Energy Technology Data Exchange (ETDEWEB)

    Loefgren, Martin; Neretnieks, Ivars [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Chemical Engineering and Technology

    2002-10-01

    Matrix diffusion has been identified as one of the most important mechanisms governing the retardation of radionuclides escaping from a deep geological repository for nuclear waste. Radionuclides dissolved in groundwater flowing in water-bearing fractures will diffuse into water filled micropores in the rock. Important parameters governing the matrix diffusion are the formation factor, the surface diffusion and sorption. This report focuses on the formation factor in undisturbed intrusive igneous rock and the possibility of measuring this parameter in-situ. The background to and the methodology of formation factor logging in-situ by electrical methods are given. The formation factor is here defined as a parameter only depending on the geometry of the porous system and not on the diffusing specie. Traditionally the formation factor has been measured by through diffusion experiments on core samples, which are costly and time consuming. It has been shown that the formation factor could also be measured by electrical methods that are faster and less expensive. Previously this has only been done quantitatively in the laboratory on a centimetre or decimetre scale. When measuring the formation factor in-situ in regions with saline groundwater only the rock resistivity and the pore water resistivity are needed. The rock resistivity could be obtained by a variety of geophysical downhole tools. Water-bearing fractures disturb the measurements and data possibly affected by free water has to be sorted out. This could be done without loosing too much data if the vertical resolution of the tool is high enough. It was found that the rock resistivity tool presently used by SKB are neither quantitative or have enough vertical resolution. Therefore the slimhole Dual-Laterolog from Antares was tested with good results. This tool has a high vertical resolution and gives quantitative rock resistivities that need no correction. At present there is no method of directly obtaining the

  2. Analytical Aerodynamic Simulation Tools for Vertical Axis Wind Turbines

    International Nuclear Information System (INIS)

    Wind power is a renewable energy source that is today the fastest growing solution to reduce CO2 emissions in the electric energy mix. Upwind horizontal axis wind turbine with three blades has been the preferred technical choice for more than two decades. This horizontal axis concept is today widely leading the market. The current PhD thesis will cover an alternative type of wind turbine with straight blades and rotating along the vertical axis. A brief overview of the main differences between the horizontal and vertical axis concept has been made. However the main focus of this thesis is the aerodynamics of the wind turbine blades. Making aerodynamically efficient turbines starts with efficient blades. Making efficient blades requires a good understanding of the physical phenomena and effective simulations tools to model them. The specific aerodynamics for straight bladed vertical axis turbine flow are reviewed together with the standard aerodynamic simulations tools that have been used in the past by blade and rotor designer. A reasonably fast (regarding computer power) and accurate (regarding comparison with experimental results) simulation method was still lacking in the field prior to the current work. This thesis aims at designing such a method. Analytical methods can be used to model complex flow if the geometry is simple. Therefore, a conformal mapping method is derived to transform any set of section into a set of standard circles. Then analytical procedures are generalized to simulate moving multibody sections in the complex vertical flows and forces experienced by the blades. Finally the fast semi analytical aerodynamic algorithm boosted by fast multipole methods to handle high number of vortices is coupled with a simple structural model of the rotor to investigate potential aeroelastic instabilities. Together with these advanced simulation tools, a standard double multiple streamtube model has been developed and used to design several straight bladed

  3. Comparison of Seven Methods for Boolean Factor Analysis and Their Evaluation by Information Gain.

    Science.gov (United States)

    Frolov, Alexander A; Húsek, Dušan; Polyakov, Pavel Yu

    2016-03-01

    An usual task in large data set analysis is searching for an appropriate data representation in a space of fewer dimensions. One of the most efficient methods to solve this task is factor analysis. In this paper, we compare seven methods for Boolean factor analysis (BFA) in solving the so-called bars problem (BP), which is a BFA benchmark. The performance of the methods is evaluated by means of information gain. Study of the results obtained in solving BP of different levels of complexity has allowed us to reveal strengths and weaknesses of these methods. It is shown that the Likelihood maximization Attractor Neural Network with Increasing Activity (LANNIA) is the most efficient BFA method in solving BP in many cases. Efficacy of the LANNIA method is also shown, when applied to the real data from the Kyoto Encyclopedia of Genes and Genomes database, which contains full genome sequencing for 1368 organisms, and to text data set R52 (from Reuters 21578) typically used for label categorization.

  4. Introductory lecture on triple-axis spectrometer

    International Nuclear Information System (INIS)

    Triple-axis spectrometer is a multi-purpose instrument for powder neutron diffraction, single crystal neutron diffraction, powder inelastic neutron scattering, single crystal inelastic neutron scattering, and neutron polarization analysis. In this lecture how to use the triple-axis spectrometer is explained for the beginners. (author)

  5. Using a fuzzy DEMATEL method for analyzing the factors influencing subcontractors selection

    Science.gov (United States)

    Kozik, Renata

    2016-06-01

    Subcontracting is a long-standing practice in the construction industry. This form of project organization, if manage properly, could provide the better quality, reduction in project time and costs. Subcontractors selection is a multi-criterion problem and can be determined by many factors. Identifying the importance of each of them as well as the direction of cause-effect relations between various types of factors can improve the management process. Their values could be evaluated on the basis of the available expert opinions with the application of a fuzzy multi-stage grading scale. In this paper it is recommended to use fuzzy DEMATEL method to analyze the relationship between factors affecting subcontractors selection.

  6. Method for determining correction factors induced by irradiation of ionization chamber cables in large radiation field

    International Nuclear Information System (INIS)

    A simple method was developed to be suggested to hospital physicists in order to be followed during large radiation field dosimetry, to evaluate the effects of cables, connectors and extension cables irradiation and to determine correction factors for each system or geometry. All quality control tests were performed according to the International Electrotechnical Commission for three clinical dosimeters. Photon and electron irradiation effects for cables, connectors and extention cables were investigated under different experimental conditions by means of measurements of chamber sensitivity to a standard radiation source of 90Sr. The radiation induced leakage current was also measured for cables, connectors and extension cables irradiated by photons and electrons. All measurements were performed at standard dosimetry conditions. Finally, measurements were performed in large fields. Cable factors and leakage factors were determined by the relation between chamber responses for irradiated and unirradiated cables. (author)

  7. Method for exploiting bias in factor analysis using constrained alternating least squares algorithms

    Science.gov (United States)

    Keenan, Michael R.

    2008-12-30

    Bias plays an important role in factor analysis and is often implicitly made use of, for example, to constrain solutions to factors that conform to physical reality. However, when components are collinear, a large range of solutions may exist that satisfy the basic constraints and fit the data equally well. In such cases, the introduction of mathematical bias through the application of constraints may select solutions that are less than optimal. The biased alternating least squares algorithm of the present invention can offset mathematical bias introduced by constraints in the standard alternating least squares analysis to achieve factor solutions that are most consistent with physical reality. In addition, these methods can be used to explicitly exploit bias to provide alternative views and provide additional insights into spectral data sets.

  8. Determination of the principal factors of river water quality through cluster analysis method and its prediction

    Institute of Scientific and Technical Information of China (English)

    Liang GUO; Ying ZHAO; Peng WANG

    2012-01-01

    In this paper, an artificial neural network model was built to predict the Chemical Oxygen Demand (CODMn) measured by permanganate index in Songhua River. To enhance the prediction accuracy, principal factors were determined through the analysis of the weight relation between influencing factors and forecasting object using cluster analysis method, which optimized the topological structure of the prediction model input items of the artificial neural network. It was shown that application of the principal factors in water quality prediction model can improve its forecasting skill significantly through the comparison between results of prediction by artificial neural network and the measurements of the CODMn. This methodology is also applicable to various water quality prediction targets of other water bodies and it is valuable for theoretical study and practical application.

  9. Off-axis Fresnel numbers in laser systems

    Institute of Scientific and Technical Information of China (English)

    Yudong; Yao; Junyong; Zhang; Yanli; Zhang; Qunyu; Bi; Jianqiang; Zhu

    2014-01-01

    The physical meaning and essence of Fresnel numbers are discussed,and two definitions of these numbers for offaxis optical systems are proposed.The universal Fresnel number is found to be N =(a2/λz) * C1+ C2.The Rayleigh–Sommerfeld nonparaxial diffraction formula states that a simple analytical formula for the nonparaxial intensity distribution after a circular aperture can be obtained.Theoretical derivations and numerical calculations reveal that the first correction factor C1 is equal to cos θ and the second factor C2 is a function of the incident wavefront and the shape of the diffractive aperture.Finally,some diffraction phenomena in off-axis optical systems are explained by the off-axis Fresnel number.

  10. Expression and correIation of HLA-G1 and Th17/Tregs axis associated reguIatory factors in B-ALL%HLA-G1及 Th17/Tregs 轴相关免疫调节分子在 B-ALL 中的表达变化及其相关性分析

    Institute of Scientific and Technical Information of China (English)

    王欣玉; 胡峻岩; 金真伊; 陈少华; 杨力建; 卢育洪; 吴秀丽; 李扬秋

    2016-01-01

    分子表达水平无显著相关关系(P 均>0.05)。对照组HLA-G1表达水平与 t-bet 表达水平呈负相关(r =-0.665;P <0.05),与其他免疫相关调节分子均未见显著相关关系(P 均>0.05)。结论初发及复发 B-ALL 患者外周血中膜结合型 HLA-G1基因表达水平显著升高,缓解后HLA-G1基因水平下降;且初发患者 HLA-G1表达水平与 IL-17A 和 FOXP3存在正相关关系,ROR-γ基因与复发 B-ALL 关系密切。HLA-G1和 ROR-γ可能参与调节 Th17/Tregs 轴的平衡,影响 B-ALL 预后。%Objective To investigate the expression changes of human leukocyte antigen-G1 (HLA-G1)and Th17 /Tregs axis associated regulatory factors (FOXP3,IL-17A,IL-23,ROR-γ,RORα,t-bet,GATA-3 and CD25)in periph-eral blood from adult patients with B-cell acute lymphocytic leukemia (B-ALL)and its correlation.Methods The mRNA expression levels of HLA-G and Th17 /Tregs axis associated regulatory factors (FOXP3,IL-17A,IL-23,ROR-γ,RORα, t-bet,GATA-3 and CD25)were detected in peripheral blood from 29 cases of MICMtype-confirmed patients with B-ALL, including 14 cases of primary patients (primary group),8 cases of patients with refractory relapse B-ALL (recurrence group)and 7 cases of patients with complete remission (CR)(remission group)by real-time quantification RT-PCR. Meanwhile,10 healthy individuals (HI)were selected as the control group.Results The expression levels of HLA-G1 gene in the primary group,recurrence group,remission group and control group were 0.415%,0.565%,0.108% and 0.110%,respectively.Significant differences were found among the primary group,recurrence group,remission group and control group (all P 0.05).In the recurrence group,no statistically significant correlation was found between the HLA-G1 ex-pression and Th17 /Tregs axis associated regulatory factors (FOXP3,IL-17A,IL-23,ROR-γ,RORα,t-bet,GATA-3 and CD25)(all P >0.05).In the remission group,a negative correlation was found

  11. Exploratory factor analysis and reliability analysis with missing data: A simple method for SPSS users

    Directory of Open Access Journals (Sweden)

    Bruce Weaver

    2014-09-01

    Full Text Available Missing data is a frequent problem for researchers conducting exploratory factor analysis (EFA or reliability analysis. The SPSS FACTOR procedure allows users to select listwise deletion, pairwise deletion or mean substitution as a method for dealing with missing data. The shortcomings of these methods are well-known. Graham (2009 argues that a much better way to deal with missing data in this context is to use a matrix of expectation maximization (EM covariances(or correlations as input for the analysis. SPSS users who have the Missing Values Analysis add-on module can obtain vectors ofEM means and standard deviations plus EM correlation and covariance matrices via the MVA procedure. But unfortunately, MVA has no /MATRIX subcommand, and therefore cannot write the EM correlations directly to a matrix dataset of the type needed as input to the FACTOR and RELIABILITY procedures. We describe two macros that (in conjunction with an intervening MVA command carry out the data management steps needed to create two matrix datasets, one containing EM correlations and the other EM covariances. Either of those matrix datasets can then be used asinput to the FACTOR procedure, and the EM correlations can also be used as input to RELIABILITY. We provide an example that illustrates the use of the two macros to generate the matrix datasets and how to use those datasets as input to the FACTOR and RELIABILITY procedures. We hope that this simple method for handling missing data will prove useful to both students andresearchers who are conducting EFA or reliability analysis.

  12. Analytical linear energy transfer model including secondary particles: calculations along the central axis of the proton pencil beam

    Science.gov (United States)

    Marsolat, F.; De Marzi, L.; Pouzoulet, F.; Mazal, A.

    2016-01-01

    In proton therapy, the relative biological effectiveness (RBE) depends on various types of parameters such as linear energy transfer (LET). An analytical model for LET calculation exists (Wilkens’ model), but secondary particles are not included in this model. In the present study, we propose a correction factor, L sec, for Wilkens’ model in order to take into account the LET contributions of certain secondary particles. This study includes secondary protons and deuterons, since the effects of these two types of particles can be described by the same RBE-LET relationship. L sec was evaluated by Monte Carlo (MC) simulations using the GATE/GEANT4 platform and was defined by the ratio of the LET d distributions of all protons and deuterons and only primary protons. This method was applied to the innovative Pencil Beam Scanning (PBS) delivery systems and L sec was evaluated along the beam axis. This correction factor indicates the high contribution of secondary particles in the entrance region, with L sec values higher than 1.6 for a 220 MeV clinical pencil beam. MC simulations showed the impact of pencil beam parameters, such as mean initial energy, spot size, and depth in water, on L sec. The variation of L sec with these different parameters was integrated in a polynomial function of the L sec factor in order to obtain a model universally applicable to all PBS delivery systems. The validity of this correction factor applied to Wilkens’ model was verified along the beam axis of various pencil beams in comparison with MC simulations. A good agreement was obtained between the corrected analytical model and the MC calculations, with mean-LET deviations along the beam axis less than 0.05 keV μm-1. These results demonstrate the efficacy of our new correction of the existing LET model in order to take into account secondary protons and deuterons along the pencil beam axis.

  13. Yaw dynamics of horizontal axis wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, A.C. (Utah Univ., Salt Lake City, UT (United States))

    1992-05-01

    Designers of a horizontal axis wind turbine yaw mechanism are faced with a difficult decision. They know that if they elect to use a yaw- controlled rotor then the system will suffer increased initial cost and increased inherent maintenance and reliability problems. On the other hand, if they elect to allow the rotor to freely yaw they known they will have to account for unknown and random, though bounded, yaw rates. They will have a higher-risk design to trade-off against the potential for cost savings and reliability improvement. The risk of a yaw-free system could be minimized if methods were available for analyzing and understanding yaw behavior. The complexity of yaw behavior has, until recently, discouraged engineers from developing a complete yaw analysis method. The objectives of this work are to (1) provide a fundamental understanding of free-yaw mechanics and the design concepts most effective at eliminating yaw problems, and (2) provide tested design tools and guidelines for use by free-yaw wind systems manufacturers. The emphasis is on developing practical and sufficiently accurate design methods.

  14. An automated Monte-Carlo based method for the calculation of cascade summing factors

    Science.gov (United States)

    Jackson, M. J.; Britton, R.; Davies, A. V.; McLarty, J. L.; Goodwin, M.

    2016-10-01

    A versatile method has been developed to calculate cascade summing factors for use in quantitative gamma-spectrometry analysis procedures. The proposed method is based solely on Evaluated Nuclear Structure Data File (ENSDF) nuclear data, an X-ray energy library, and accurate efficiency characterisations for single detector counting geometries. The algorithm, which accounts for γ-γ, γ-X, γ-511 and γ-e- coincidences, can be applied to any design of gamma spectrometer and can be expanded to incorporate any number of nuclides. Efficiency characterisations can be derived from measured or mathematically modelled functions, and can accommodate both point and volumetric source types. The calculated results are shown to be consistent with an industry standard gamma-spectrometry software package. Additional benefits including calculation of cascade summing factors for all gamma and X-ray emissions, not just the major emission lines, are also highlighted.

  15. Research on Design Method of the Full Form Ship with Minimum Thrust Deduction Factor

    Institute of Scientific and Technical Information of China (English)

    张宝吉; 缪爱琴; 张竹心

    2015-01-01

    In the preliminary design stage of the full form ships, in order to obtain a hull form with low resistance and maximum propulsion efficiency, an optimization design program for a full form ship with the minimum thrust deduction factor has been developed, which combined the potential flow theory and boundary layer theory with the optimization technique. In the optimization process, the Sequential Unconstrained Minimization Technique (SUMT) interior point method of Nonlinear Programming (NLP) was proposed with the minimum thrust deduction factor as the objective function. An appropriate displacement is a basic constraint condition, and the boundary layer separation is an additional one. The parameters of the hull form modification function are used as design variables. At last, the numerical optimization example for lines of after-body of 50000 DWT product oil tanker was provided, which indicated that the propulsion efficiency was improved distinctly by this optimal design method.

  16. Determination of corrective factors for an ultrasonic flow measuring method in pipes accounting for perturbations

    International Nuclear Information System (INIS)

    By current ultrasonic flow measuring equipment (UFME) the mean velocity is measured for one or two measuring paths. This mean velocity is not equal to the velocity averaged over the flow cross-section, by means of which the flow rate is calculated. This difference will be found already for axially symmetrical, fully developed velocity profiles and, to a larger extent, for disturbed profiles varying in flow direction and for nonsteady flow. Corrective factors are defined for steady and nonsteady flows. These factors can be derived from the flow profiles within the UFME. By mathematical simulation of the entrainment effect the influence of cross and swirl flows on various ultrasonic measuring methods is studied. The applied UFME with crossed measuring paths is shown to be largely independent of cross and swirl flows. For evaluation in a computer of velocity network measurements in circular cross-sections the equations for interpolation and integration are derived. Results of the mathematical method are the isotach profile, the flow rate and, for fully developed flow, directly the corrective factor. In the experimental part corrective factors are determined in nonsteady flow in a measuring plane before and in form measuring planes behind a perturbation. (orig./RW)

  17. Methods for Determining the Activity Concentration Calibration Factor for Ventilation Duct in Cyclotron Sites

    International Nuclear Information System (INIS)

    Cyclotrons are commonly used for production of radioactive isotopes for nuclear medicine purposes. The nuclear process requires installation of a ventilation stack. According to the regulations in many countries, the released activity should be monitored and controlled in order to limit air pollution. This requires a stuck radiation detector and determining a converting factor that will translate the radiation detector reading into activity concentration units. Calibrating the conversion factor is done mainly by releasing a known amount of activity. Having a preliminary estimation of the conversion factor, during the site construction stage, is an important option for the duct configuration design, in order to achieve the required detection sensitivity. An algorithm for estimating the stack concentration calibration factor in positron emitting isotopes producing sites was developed. The algorithm which is described in this article is based on three independent methods that consist of MCNP simulations analytical calculations and experimental setup with controlled static calibration releases of gaseous 18F which was produced especially for this purpose by the cyclotron site in Soreq Nuclear Research Center Israel. The specified methods applied on few stack sections with different shapes and sizes

  18. Weight Determining of Factors Influencing Grain Output Based on Entropy Weight Method

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    This article selects 8 main factors(the number of rural employees,total power of agricultural machinery,effective irrigation area of crops,growing area of grain crops,fertilizer consumption,electricity consumption in rural areas,area affected and area covered) as the factors influencing grain output,and offers the method of determining weight of factors influencing grain output using entropy weight method.According to the relevant data in the period 1985-2005,we analyze the weight of factors influencing grain output in China by example.The results show that the electricity consumption in rural areas has the greatest impact on grain output,followed by total power of agricultural machinery,fertilizer consumption and area covered.To increase grain output,we must enhance the degree of mechanization,free people from the former process of direct cultivation,strengthen water conservancy construction,and do a good job in disaster prevention and mitigation.

  19. Neuropeptides and the Microbiota-Gut-Brain Axis

    OpenAIRE

    Holzer, Peter; Farzi, Aitak

    2014-01-01

    Neuropeptides are important mediators both within the nervous system and between neurons and other cell types. Neuropeptides such as substance P, calcitonin gene-related peptide and neuropeptide Y (NPY), vasoactive intestinal polypeptide, somatostatin and corticotropin-releasing factor are also likely to play a role in the bidirectional gut-brain communication. In this capacity they may influence the activity of the gastrointestinal microbiota and its interaction with the gut-brain axis. Curr...

  20. Assessment concept for the building design process using the Eco-factor method

    DEFF Research Database (Denmark)

    Wahlström, Åsa; Brohus, Henrik

    2006-01-01

    During the last years the pressure for energy improvement has increased. However, a one-sided focus on energy efficiency might be introduced at the expense of indoor climate. Therefore, it is essential that energy optimisation is integrated with assessment of indoor climate. A guideline tool with...... an assessment concept based on the so-called Eco-factor method been developed for an integrated design process....

  1. Crisis of the balance of payments: factors, indicators and prevention methods

    OpenAIRE

    O. Chernyak, V. Khomiak

    2011-01-01

    The authors analyze the structure and main factors of the crisis of balance of payments in Ukraine's economy. The article considers the existing methods and indicators, which may signal about the approaching balance of payments crisis, as well as the main approaches to modeling such crises, among which the most suitable for Ukraine ones are defined. The authors provide models of the main components of balance of payments, which signal about the crisis and select a set of indicators producing ...

  2. Factors associated with low fitness in adolescents – A mixed methods study

    OpenAIRE

    Charlton, Richard; Gravenor, Michael B; Rees, Anwen; Knox, Gareth; Hill, Rebecca; Rahman, Muhammad A.; Jones, Kerina; Christian, Danielle; Julien S Baker; Stratton, Gareth; Brophy, Sinead

    2014-01-01

    Background Fitness and physical activity are important for cardiovascular and mental health but activity and fitness levels are declining especially in adolescents and among girls. This study examines clustering of factors associated with low fitness in adolescents in order to best target public health interventions for young people. Methods 1147 children were assessed for fitness, had blood samples, anthropometric measures and all data were linked with routine electronic data to examine educ...

  3. Developmental Testing of Habitability and Human Factors Tools and Methods During Neemo 15

    Science.gov (United States)

    Thaxton, S. S.; Litaker, H. L., Jr.; Holden, K. L.; Adolf, J. A.; Pace, J.; Morency, R. M.

    2011-01-01

    Currently, no established methods exist to collect real-time human factors and habitability data while crewmembers are living aboard the International Space Station (ISS), traveling aboard other space vehicles, or living in remote habitats. Currently, human factors and habitability data regarding space vehicles and habitats are acquired at the end of missions during postflight crew debriefs. These debriefs occur weeks or often longer after events have occurred, which forces a significant reliance on incomplete human memory, which is imperfect. Without a means to collect real-time data, small issues may have a cumulative effect and continue to cause crew frustration and inefficiencies. Without timely and appropriate reporting methodologies, issues may be repeated or lost. TOOL DEVELOPMENT AND EVALUATION: As part of a directed research project (DRP) aiming to develop and validate tools and methods for collecting near real-time human factors and habitability data, a preliminary set of tools and methods was developed. These tools and methods were evaluated during the NASA Extreme Environments Mission Operations (NEEMO) 15 mission in October 2011. Two versions of a software tool were used to collect observational data from NEEMO crewmembers that also used targeted strategies for using video cameras to collect observations. Space habitability observation reporting tool (SHORT) was created based on a tool previously developed by NASA to capture human factors and habitability issues during spaceflight. SHORT uses a web-based interface that allows users to enter a text description of any observations they wish to report and assign a priority level if changes are needed. In addition to the web-based format, a mobile Apple (iOS) format was implemented, referred to as iSHORT. iSHORT allows users to provide text, audio, photograph, and video data to report observations. iSHORT can be deployed on an iPod Touch, iPhone, or iPad; for NEEMO 15, the app was provided on an iPad2.

  4. The Financial Impact of Risk Factors Affecting Project Cost Contingency: Evidential Reasoning Method

    OpenAIRE

    Emmanuel Abeere-Inga; Joseph Ignatius Teye Buertey; Theophilus Adjei Kumi

    2013-01-01

    The process of cost modeling using risk analysis for construction projects is very crucial for the achievement of project success. The purpose of this paper is to present an analysis of the financial impact of risk factors affecting key construction work sections; using a systematic risk methodology based on empirical judgment. The failure mode effect analysis (FMEA) and the evidential reasoning methods are presented as qualitative and quantitative risk tools respectively. Data analysis from ...

  5. Research on the Influence Factors on the Crop Food Supply Price using Data Envelopment Analysis Method

    OpenAIRE

    Wang Yan

    2013-01-01

    The study aims to investigate the influence factors on the crop food supply price using the Data Envelopment Analysis (DEA) method. Crops are the basic food rations for urban and rural residents and occupy the most important position in the food consumption. The price of the crop food has important influence on the stable economic operation and even social stability in China; hence it is crucial to find out the fluctuation rules and formation mechanism of crop food supply price. However, ther...

  6. Recognition of Factors Affecting Students Trust in Virtual Universities Using Delphi Method

    OpenAIRE

    Mohammad A. Sarlak; Ali R. Aliahmadi

    2008-01-01

    At the present time in Islamic Republic of Iran the Virtual Universities are operating beside the Non- virtual universities. The problem that virtual universities now confront is low level of students trust which applying to these universities. The current research tries to recognize factors affecting students trust in Virtual Universities using Delphi Method. This qualitative study examined the opinions of a diverse group of participating experts in the area of information technology and vir...

  7. New uncertainties in QCD-QED rescaling factors using quadrature method

    Indian Academy of Sciences (India)

    Mahadev Patgiri; N Nimai Singh

    2005-12-01

    In this paper we briefly outline the quadrature method for estimating uncertainties in a function which depends on several variables, and apply it to estimate the numerical uncertainties in QCD-QED rescaling factors. We employ here the one-loop order in QED and three-loop order in QCD evolution equations of the fermion mass renormalisation. Our present calculation is found to be new and also reliable when compared to the earlier values employed by various authors.

  8. A semi-supervised method for predicting transcription factor-gene interactions in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Jason Ernst

    2008-03-01

    Full Text Available While Escherichia coli has one of the most comprehensive datasets of experimentally verified transcriptional regulatory interactions of any organism, it is still far from complete. This presents a problem when trying to combine gene expression and regulatory interactions to model transcriptional regulatory networks. Using the available regulatory interactions to predict new interactions may lead to better coverage and more accurate models. Here, we develop SEREND (SEmi-supervised REgulatory Network Discoverer, a semi-supervised learning method that uses a curated database of verified transcriptional factor-gene interactions, DNA sequence binding motifs, and a compendium of gene expression data in order to make thousands of new predictions about transcription factor-gene interactions, including whether the transcription factor activates or represses the gene. Using genome-wide binding datasets for several transcription factors, we demonstrate that our semi-supervised classification strategy improves the prediction of targets for a given transcription factor. To further demonstrate the utility of our inferred interactions, we generated a new microarray gene expression dataset for the aerobic to anaerobic shift response in E. coli. We used our inferred interactions with the verified interactions to reconstruct a dynamic regulatory network for this response. The network reconstructed when using our inferred interactions was better able to correctly identify known regulators and suggested additional activators and repressors as having important roles during the aerobic-anaerobic shift interface.

  9. Thermal Comfort Assessment and Optimization of Environmental Factors by Using Taguchi Method

    Directory of Open Access Journals (Sweden)

    A. R. Ismail

    2009-01-01

    Full Text Available Problem statement: The objective of this study was to determine the dominance effects of environmental factors such as Illuminance (lux, relative humidity (% and WBGT (°C on the operators’ productivity at Malaysian automotive industry. Approach: One automotive parts assembly factory had been chosen as a subject for the study. The subjects were workers at the assembly section of the factory. The environment examined was the Illuminance (lux, relative humidity (% and WBGT (°C of the surrounding workstation area. Two sets of representative data including the Illuminance, relative humidity (% and WBGT (°C level and production rate were collected during the study. All the data was measured using Babuc apparatus which is capable to measure simultaneously those mentioned environmental factors. The time series data of fluctuating level of environmental were plotted to identify the significant changes of factors. Then Taguchi Method was being utilized to find the sequence of dominance factors that contributed to the productivity of operator at the specified production workstation. From there, optimum level for the three factors will be determine for optimum productivity. Further multiple linear regressions were employed to obtain the equation model in order to represent the relationship of these environmental factors towards productivity. Results: The thermal comfort assessments of this station which was the scale PMV was 2 and PPD is 79% ware likely to be satisfied by the worker. Conclusion: The study revealed that the dominant factor contribute to the productivity at the body assembly production line is WBGT and Illuminance whereas the empirical finding was closely related to the perception study by survey questionnaire distribution.

  10. An alternative approach for addressing the failure probability-safety factor method with sensitivity analysis

    Energy Technology Data Exchange (ETDEWEB)

    Castillo, Enrique; Conejo, Antonio J.; Minguez, Roberto; Castillo, Carmen

    2003-11-01

    The paper introduces a method for solving the failure probability-safety factor problem for designing engineering works proposed by Castillo et al. that optimizes an objective function subject to the standard geometric and code constraints, and two more sets of constraints that simultaneously guarantee given safety factors and failure probability bounds associated with a given set of failure modes. The method uses the dual variables and is especially convenient to perform a sensitivity analysis, because sensitivities of the objective function and the reliability indices can be obtained with respect to all data values. To this end, the optimization problems are transformed into other equivalent ones, in which the data parameters are converted into artificial variables, and locked to their actual values. In this way, some variables of the associated dual problems become the desired sensitivities. In addition, using the proposed methodology, calibration of codes based on partial safety factors can be done. The method is illustrated by its application to the design of a simple rubble mound breakwater and a bridge crane.

  11. Calculation of the fast multiplication factor by the fission matrix method

    International Nuclear Information System (INIS)

    A variation of the Monte Carlo method to calculate an effective breeding factor of a nuclear reactor is described. The evaluation procedure of reactivity perturbations by the Monte Carlo method in the first order perturbation theory is considered. The method consists in reducing an integral neutron transport equation to a set of linear algebraic equations. The coefficients of this set are elements of a fission matrix. The fission matrix being a Grin function of the neutron transport equation, is evaluated by the Monte Carlo method. In the program realizing the suggested algorithm, the game for initial neutron energy of a fission spectrum and then for the region of neutron birth, ΔVsub(f)sup(i)has been played in proportion to the product of Σsub(f)sup(i)ΔVsub(f)sup(i), where Σsub(f)sup(i) is a macroscopic cross section in the region numbered at the birth energy. Further iterations of a space distribution of neutrons in the system are performed by the generation method. In the adopted scheme of simulation of neutron histories the emission of secondary neutrons is controlled by weights; it occurs at every collision and not only in the end on the history. The breeding factor is calculated simultaneously with the space distribution of neutron worth in the system relative to the fission process and neutron flux. Efficiency of the described procedure has been tested on the calculation of the breeding factor for the Godiva assembly, simulating a fast reactor with a hard spectrum. A high accuracy of calculations at moderate number of zones in the core and reasonable statistics has been stated

  12. Axis intersection measurement of three-axis turntable with two crosshair targets

    Institute of Scientific and Technical Information of China (English)

    REN Shun-qing; MA Guang-cheng; WANG Chang-hong

    2005-01-01

    In order to measure three-axis intersection error, two crosshair targets were fixed in the inner axis frame of a three-axis turntable. Also a theodolite was used to point its telescope to the targets and to measure the horizontal angles when three axes were on equi-spaced angle positions. The calculation equations of the axis intersection were deduced from the mounting position of the theodolite, positions of two targets, angular positions of three axes, and the measured horizontal angles with the theodolite. Finally, a practical measurement is carried out on a horizontal three-axis turntable and error analysis is conducted.

  13. Angiotensin type 2 receptor stimulation ameliorates left ventricular fibrosis and dysfunction via regulation of tissue inhibitor of matrix metalloproteinase 1/matrix metalloproteinase 9 axis and transforming growth factor β1 in the rat heart.

    Science.gov (United States)

    Lauer, Dilyara; Slavic, Svetlana; Sommerfeld, Manuela; Thöne-Reineke, Christa; Sharkovska, Yuliya; Hallberg, Anders; Dahlöf, Bjorn; Kintscher, Ulrich; Unger, Thomas; Steckelings, Ulrike Muscha; Kaschina, Elena

    2014-03-01

    Left ventricular (LV) remodeling is the main reason for the development of progressive cardiac dysfunction after myocardial infarction (MI). This study investigated whether stimulation of the angiotensin type 2 receptor is able to ameliorate post-MI cardiac remodeling and what the underlying mechanisms may be. MI was induced in Wistar rats by permanent ligation of the left coronary artery. Treatment with the angiotensin type 2 receptor agonist compound 21 (0.03 mg/kg) was started 6 hours post-MI and continued for 6 weeks. Hemodynamic parameters were measured by echocardiography and intracardiac catheter. Effects on proteolysis were studied in heart tissue and primary cardiac fibroblasts. Compound 21 significantly improved systolic and diastolic functions, resulting in improved ejection fraction (71.2±4.7% versus 53.4±7.0%; Pventricular filling velocities, and maximum and minimum rate of LV pressure rise (P<0.05). Compound 21 improved arterial stiffness parameters and reduced collagen content in peri-infarct myocardium. Tissue inhibitor of matrix metalloproteinase 1 was strongly upregulated, whereas matrix metalloproteinases 2 and 9 and transforming growth factor β1 were diminished in LV of treated animals. In cardiac fibroblasts, compound 21 initially induced tissue inhibitor of matrix metalloproteinase 1 expression followed by attenuated matrix metalloproteinase 9 and transforming growth factor β1 secretion. In conclusion, angiotensin type 2 receptor stimulation improves cardiac function and prevents cardiac remodeling in the late stage after MI, suggesting that angiotensin type 2 receptor agonists may be considered a future pharmacological approach for the improvement of post-MI cardiac dysfunction.

  14. Prognostic factors for success in the Kangaroo Mother Care method for low birth weight babies

    Directory of Open Access Journals (Sweden)

    Rina Pratiwi

    2016-02-01

    Full Text Available Background Low birth weight (LBW is closely related to neonatal morbidity and mortality. Management of LBW infants in developing countries remains limited, due to the low availability of incubators. The Kangaroo Mother Care (KMC method has been shown to be effective for newborns, especially LBW infants, in which skin-to-skin contact may be conducive for infants’ weight gain, thermoregulation, and heart rate stability.Objective To determine the prognostic factors for KMC success in LBW babies.Methods This cohort study included LBW infants at Dr. Kariadi General Government Hospital, Semarang, by a consecutive sampling method. Success of KMC was assessed by infant weight gain, as well as stabilization of temperature, heart rate, and respiration. Prognostic factors for KMC success that we assessed were birth weight, gestational age, KMC duration, age at KMC onset and maternal education level. Statistical analyses used were Chi-square and relative risk (RR tests.Results Of 40 LBW infants, 24 were successful in KMC. Birth weight ≥ 1500 grams (RR 0.4; 95%CI 0.23 to 0.73; P=0.001], gestational age ≥ 34 weeks (RR 0.94; 95%CI 0.46 to 1.89; P=1.00, KMC duration ≥ 65 minutes (RR 1.44; 95%CI 0.76 to 2.75; P= 0.215, high maternal education level (RR 1.25; 95%CI 0.76 to 2.04; P=0.408, and age at KMC onset >10 days (RR 2.69; 95%CI 1.14 to 6.32; P=0.003, were factors that related to the successful of KMC.Conclusion Age at KMC onset > 10 days was a prognostic factor for KMC success in low birth weight babies.

  15. Methods for detrending success metrics to account for inflationary and deflationary factors*

    Science.gov (United States)

    Petersen, A. M.; Penner, O.; Stanley, H. E.

    2011-01-01

    Time-dependent economic, technological, and social factors can artificially inflate or deflate quantitative measures for career success. Here we develop and test a statistical method for normalizing career success metrics across time dependent factors. In particular, this method addresses the long standing question: how do we compare the career achievements of professional athletes from different historical eras? Developing an objective approach will be of particular importance over the next decade as major league baseball (MLB) players from the "steroids era" become eligible for Hall of Fame induction. Some experts are calling for asterisks (*) to be placed next to the career statistics of athletes found guilty of using performance enhancing drugs (PED). Here we address this issue, as well as the general problem of comparing statistics from distinct eras, by detrending the seasonal statistics of professional baseball players. We detrend player statistics by normalizing achievements to seasonal averages, which accounts for changes in relative player ability resulting from a range of factors. Our methods are general, and can be extended to various arenas of competition where time-dependent factors play a key role. For five statistical categories, we compare the probability density function (pdf) of detrended career statistics to the pdf of raw career statistics calculated for all player careers in the 90-year period 1920-2009. We find that the functional form of these pdfs is stationary under detrending. This stationarity implies that the statistical regularity observed in the right-skewed distributions for longevity and success in professional sports arises from both the wide range of intrinsic talent among athletes and the underlying nature of competition. We fit the pdfs for career success by the Gamma distribution in order to calculate objective benchmarks based on extreme statistics which can be used for the identification of extraordinary careers.

  16. A novel edge-preserving nonnegative matrix factorization method for spectral unmixing

    Science.gov (United States)

    Bao, Wenxing; Ma, Ruishi

    2015-12-01

    Spectral unmixing technique is one of the key techniques to identify and classify the material in the hyperspectral image processing. A novel robust spectral unmixing method based on nonnegative matrix factorization(NMF) is presented in this paper. This paper used an edge-preserving function as hypersurface cost function to minimize the nonnegative matrix factorization. To minimize the hypersurface cost function, we constructed the updating functions for signature matrix of end-members and abundance fraction respectively. The two functions are updated alternatively. For evaluation purpose, synthetic data and real data have been used in this paper. Synthetic data is used based on end-members from USGS digital spectral library. AVIRIS Cuprite dataset have been used as real data. The spectral angle distance (SAD) and abundance angle distance(AAD) have been used in this research for assessment the performance of proposed method. The experimental results show that this method can obtain more ideal results and good accuracy for spectral unmixing than present methods.

  17. An Efficient Method to Identify Conditionally Activated Transcription Factors and their Corresponding Signal Transduction Pathway Segments

    Directory of Open Access Journals (Sweden)

    Haiyan Hu

    2009-11-01

    Full Text Available A signal transduction pathway (STP is a cascade composed of a series of signal transferring steps, which often activate one or more transcription factors (TFs to control the transcription of target genes. Understanding signaling pathways is important to our understanding of the molecular mechanisms of disease. Many condition-annotated pathways have been deposited in public databases. However, condition-annotated pathways are far from complete, considering the large number of possible conditions. Computational methods to assist in the identification of conditionally activated pathways are greatly needed. In this paper, we propose an efficient method to identify conditionally activated pathway segments starting from the identification of conditionally activated TFs, by incorporating protein-DNA binding data, gene expression data and protein interaction data. Applying our methods on several microarray datasets, we have discovered many significantly activated TFs and their corresponding pathway segments, which are supported by evidence in the literature.

  18. A rapid cyclic voltammetric method for studying cement factors affecting the corrosion of reinforced concrete

    Energy Technology Data Exchange (ETDEWEB)

    Foulkes, F.R.; McGrath, P. (Univ. of Toronto, Ontario (Canada))

    1999-06-01

    A rapid cyclic voltammetric method for studying the influence of cement factors on the corrosion of embedded iron and steel in hardened cement paste is described. The technique employs a cement electrode'' consisting of an iron or steel wire embedded in a miniature cylinder of hardened cement paste. The rapid cyclic voltammetric method is fast, reproducible, and provides information on the corrosiveness of the pore solution environment surrounding the embedded metal. The usefulness of the method is demonstrated by showing how it can be used to evaluate the threshold chloride content of hardened ordinary portland cement paste at which corrosion begins and by using it to evaluate the relative efficacy of several admixed corrosion inhibitors.

  19. Classification of ECG signals using LDA with factor analysis method as feature reduction technique.

    Science.gov (United States)

    Kaur, Manpreet; Arora, A S

    2012-11-01

    The analysis of ECG signal, especially the QRS complex as the most characteristic wave in ECG, is a widely accepted approach to study and to classify cardiac dysfunctions. In this paper, first wavelet coefficients calculated for QRS complex are taken as features. Next, factor analysis procedures without rotation and with orthogonal rotation (varimax, equimax and quartimax) are used for feature reduction. The procedure uses the 'Principal Component Method' to estimate component loadings. Further, classification has been done with a LDA classifier. The MIT-BIH arrhythmia database is used and five types of beats (normal, PVC, paced, LBBB and RBBB) are considered for analysis. Accuracy, sensitivity and positive predictivity are performance parameters used for comparing performance of feature reduction techniques. Results demonstrate that the equimax rotation method yields maximum average accuracy of 99.056% for unknown data sets among other used methods.

  20. Neuropeptides and the microbiota-gut-brain axis.

    Science.gov (United States)

    Holzer, Peter; Farzi, Aitak

    2014-01-01

    Neuropeptides are important mediators both within the nervous system and between neurons and other cell types. Neuropeptides such as substance P, calcitonin gene-related peptide and neuropeptide Y (NPY), vasoactive intestinal polypeptide, somatostatin and corticotropin-releasing factor are also likely to play a role in the bidirectional gut-brain communication. In this capacity they may influence the activity of the gastrointestinal microbiota and its interaction with the gut-brain axis. Current efforts in elucidating the implication of neuropeptides in the microbiota-gut-brain axis address four information carriers from the gut to the brain (vagal and spinal afferent neurons; immune mediators such as cytokines; gut hormones; gut microbiota-derived signalling molecules) and four information carriers from the central nervous system to the gut (sympathetic efferent neurons; parasympathetic efferent neurons; neuroendocrine factors involving the adrenal medulla; neuroendocrine factors involving the adrenal cortex). Apart from operating as neurotransmitters, many biologically active peptides also function as gut hormones. Given that neuropeptides and gut hormones target the same cell membrane receptors (typically G protein-coupled receptors), the two messenger roles often converge in the same or similar biological implications. This is exemplified by NPY and peptide YY (PYY), two members of the PP-fold peptide family. While PYY is almost exclusively expressed by enteroendocrine cells, NPY is found at all levels of the gut-brain and brain-gut axis. The function of PYY-releasing enteroendocrine cells is directly influenced by short chain fatty acids generated by the intestinal microbiota from indigestible fibre, while NPY may control the impact of the gut microbiota on inflammatory processes, pain, brain function and behaviour. Although the impact of neuropeptides on the interaction between the gut microbiota and brain awaits to be analysed, biologically active peptides

  1. Factors and methods of analysis and estimation of furniture making enterprises competitiveness

    Directory of Open Access Journals (Sweden)

    Vitaliy Aleksandrovich Zhigarev

    2015-06-01

    Full Text Available Objective to describe the author39s methodology for estimating the furnituremaking enterprises competitiveness with a view to carry out the economic evaluation of the efficiency of furniture production the evaluation of the internal component of the furniture production efficiency the identification of factors influencing the efficiency of furnituremaking companies and areas for improving it through improvements in product range production and sales policy of the enterprise. The research subject is modern methods and principles of competitiveness management applicable in a rapidly changing market environment. Methods in general the research methodology consists of six stages differentiated by methods objectives and required outcomes. The first stage of the research was to study the nature of demand within the target market of a furnituremaking enterprise. The second stage was to study the expenditures of a furnituremaking enterprise for implementing individual production and sales strategies. The third stage was to study competition in the market. The fourth stage was the analysis of possibilities of a furnituremaking enterprise in producing and selling furniture in terms of factor values combinations. The fifth stage was the reexamination of the demand with a view to its distribution according to the factor space. The final sixth stage was processing of data obtained at the previous stages and carrying out the necessary calculations. Results in general the above methodology of economic evaluation of the efficiency of furniture production based on the previously developed model gives the managers of enterprises an algorithm for assessing both market and firmlevel component of the furniture production efficiency allowing the subsequent identification and evaluation of the efficiency factors and the development of measures to improve the furniture production and sale efficiency as well as the assortment rationalization production and sales policy

  2. The Financial Impact of Risk Factors Affecting Project Cost Contingency: Evidential Reasoning Method

    Directory of Open Access Journals (Sweden)

    Emmanuel Abeere-Inga

    2013-07-01

    Full Text Available The process of cost modeling using risk analysis for construction projects is very crucial for the achievement of project success. The purpose of this paper is to present an analysis of the financial impact of risk factors affecting key construction work sections; using a systematic risk methodology based on empirical judgment. The failure mode effect analysis (FMEA and the evidential reasoning methods are presented as qualitative and quantitative risk tools respectively. Data analysis from structured questionnaires revealed that four work sections are prone to high scope changes contemporaneous with seven risk factors. Contrary to the usual 10% contingency estimate allowed for construction projects in Ghana, an approximate overall physical contingency range of between 13.36% and 17.88% was determined using evidential reasoning methods. The likely impact of the integrated work sections and risk factors provide a clue to estimators on how to estimate and account for project cost contingency. The research concludes by recommending a framework for improving the estimation process of cost contingency through the integration of efficient risk management strategies, cost estimation and design management process.

  3. Pathophysiology, risk factors, and screening methods for prediabetes in women with polycystic ovary syndrome

    Science.gov (United States)

    Gourgari, Evgenia; Spanakis, Elias; Dobs, Adrian Sandra

    2016-01-01

    Polycystic ovary syndrome (PCOS) is a syndrome associated with insulin resistance (IR), obesity, infertility, and increased cardiometabolic risk. This is a descriptive review of several mechanisms that can explain the IR among women with PCOS, other risk factors for the development of diabetes, and the screening methods used for the detection of glucose intolerance in women with PCOS. Few mechanisms can explain IR in women with PCOS such as obesity, insulin receptor signaling defects, and inhibition of insulin-mediated glucose uptake in adipocytes. Women with PCOS have additional risk factors for the development of glucose intolerance such as family history of diabetes, use of oral contraceptives, anovulation, and age. The Androgen Society in 2007 and the Endocrine Society in 2013 recommended using oral glucose tolerance test as a screening tool for abnormal glucose tolerance in all women with PCOS. The approach to detection of glucose intolerance among women with PCOS varies among health care providers. Large prospective studies are still needed for the development of guidelines with strong evidence. When assessing risk of future diabetes in women with PCOS, it is important to take into account the method used for screening as well as other risk factors that these women might have.

  4. Determine the galaxy bias factors on large scales using bispectrum method

    CERN Document Server

    Guo, Hong

    2009-01-01

    We study whether the bias factors of galaxies can be unbiasedly recovered from their power spectra and bispectra. We use a set of numerical N-body simulations and construct large mock galaxy catalogs based upon the semi-analytical model of Croton et al. (2006). We measure the reduced bispectra for galaxies of different luminosity, and determine the linear and first nonlinear bias factors from their bispectra. We find that on large scales down to that of the wavenumber k=0.1h/Mpc, the bias factors b1 and b2 are nearly constant, and b1 obtained with the bispectrum method agrees very well with the expected value. The nonlinear bias factor b2 is negative, except for the most luminous galaxies with M<-23 which have a positive b2. The behavior of b2 of galaxies is consistent with the b2 mass dependence of their host halos. We show that it is essential to have an accurate estimation of the dark matter bispectrum in order to have an unbiased measurement of b1 and b2. We also test the analytical approach of incorpo...

  5. ECCO Mnemonic Authentication—Two-Factor Authentication Method with Ease-of-Use

    Directory of Open Access Journals (Sweden)

    Saman Gerami Moghaddam

    2014-06-01

    Full Text Available Not very long ago, organizations used to identify their customers by means of one-factor authentication mechanisms. In today's world, however, these mechanisms cannot overcome the new security threats at least when it comes to high risk situations. Hence, identity providers have introduced varieties of two-factor authentication mechanisms. It may be argued that users may experience difficulties at time of authentication in systems that use two-factor authentication mechanisms for example because they may be forced to carry extra devices to be authenticated more accurately. This is however the tradeoff between ease-of-use and having a secure system that may be decided by the users and not the security providers. In this paper we present a new two-factor authentication mechanism that secures systems and at the same time is easier to use. We have used mnemonic features and the cache concept to achieve ease-of-use and security, respectively. Also, we have tested our method with almost 6500 users in real world using The Mechanical Turk Developer Sandbox.

  6. 基于多轴差分吸收光谱技术的查找表法反演气溶胶消光廓线研究%Research of Aerosol Extinction Inverted with Look-Up Table Method Based on Multi-Axis Differential Optical Absorption Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    吴丰成; 谢品华; 李昂; 司福祺; 徐晋; 范广强; 刘建国; 刘文清

    2013-01-01

    The properties of aerosol include physical,chemical and optical characteristics.Whiles the determinant of optical parameters is the prerequisite for accurate estimation to the radiation forcing.A method for determining aerosol extinction with look-up table is presented combined with radiative transfer model.Also the effects of single scatter albedo rate,asymmetry parameter and ground albedo rate on the simulation of O4 air mass factor are studied.Using O4 air mass factor based on multi-axis differental optical absorption spectroscopy (MAX-DOAS) measurement at different elevation angles,simulated O4 air mass factor and the factor got through the radiative transfer model are compared.The aerosol optical density,boundary height and extinction coeffcient are retrieved after the process of minimization and linearly interpolation.Creating a look-up table,the aerosol extinction is determined at Shanghai Baoshan monitoring site using MAX-DOAS.Compared with lidar,it sows a reasonable agreement.It's turned out that the look-up table can be used to detect the properties of aerosol.%大气气溶胶特性包括气溶胶的物理、化学、光学特性,而气溶胶光学参数的确定是准确估算辐射强迫的前提条件.提出一种结合大气辐射传输模型,利用查表法反演气溶胶消光的方法,研究了单次散射反照率、非对称因子及地表反照率等输入参数对模拟氧的二聚体(O4)大气质量因子的影响.利用多轴差分吸收光谱(MAX-DOAS)技术在不同仰角下进行测量,将计算得到的O4的大气质量因子与辐射传输模型计算的大气质量因子做比较,通过最小化及线性插值过程反演出气溶胶的光学厚度、边界层高度及地面消光系数.建立查找表,以上海宝山监测点多轴差分吸收光谱仪测量为例,反演出气溶胶的消光,并与雷达监测数据做对比,两者具有较好的一致性.结果表明,查表法可以实现气溶胶特性的探测.

  7. ObStruct: a method to objectively analyse factors driving population structure using Bayesian ancestry profiles.

    Directory of Open Access Journals (Sweden)

    Velimir Gayevskiy

    Full Text Available Bayesian inference methods are extensively used to detect the presence of population structure given genetic data. The primary output of software implementing these methods are ancestry profiles of sampled individuals. While these profiles robustly partition the data into subgroups, currently there is no objective method to determine whether the fixed factor of interest (e.g. geographic origin correlates with inferred subgroups or not, and if so, which populations are driving this correlation. We present ObStruct, a novel tool to objectively analyse the nature of structure revealed in Bayesian ancestry profiles using established statistical methods. ObStruct evaluates the extent of structural similarity between sampled and inferred populations, tests the significance of population differentiation, provides information on the contribution of sampled and inferred populations to the observed structure and crucially determines whether the predetermined factor of interest correlates with inferred population structure. Analyses of simulated and experimental data highlight ObStruct's ability to objectively assess the nature of structure in populations. We show the method is capable of capturing an increase in the level of structure with increasing time since divergence between simulated populations. Further, we applied the method to a highly structured dataset of 1,484 humans from seven continents and a less structured dataset of 179 Saccharomyces cerevisiae from three regions in New Zealand. Our results show that ObStruct provides an objective metric to classify the degree, drivers and significance of inferred structure, as well as providing novel insights into the relationships between sampled populations, and adds a final step to the pipeline for population structure analyses.

  8. Characterization of a multi-axis ion chamber array

    International Nuclear Information System (INIS)

    Purpose: The aim of this work was to characterize a multi-axis ion chamber array (IC PROFILER; Sun Nuclear Corporation, Melbourne, FL USA) that has the potential to simplify the acquisition of LINAC beam data. Methods: The IC PROFILER (or panel) measurement response was characterized with respect to radiation beam properties, including dose, dose per pulse, pulse rate frequency (PRF), and energy. Panel properties were also studied, including detector-calibration stability, power-on time, backscatter dependence, and the panel's agreement with water tank measurements [profiles, fractional depth dose (FDD), and output factors]. Results: The panel's relative deviation was typically within (±) 1% of an independent (or nominal) response for all properties that were tested. Notable results were (a) a detectable relative field shape change of ∼1% with linear accelerator PRF changes; (b) a large range in backscatter thickness had a minimal effect on the measured dose distribution (typically less than 1%); (c) the error spread in profile comparison between the panel and scanning water tank (Blue Phantom, CC13; IBA Schwarzenbruck, DE) was approximately (±) 0.75%. Conclusions: The ability of the panel to accurately reproduce water tank profiles, FDDs, and output factors is an indication of its abilities as a dosimetry system. The benefits of using the panel versus a scanning water tank are less setup time and less error susceptibility. The same measurements (including device setup and breakdown) for both systems took 180 min with the water tank versus 30 min with the panel. The time-savings increase as the measurement load is increased.

  9. Pursuing an ecological component for the Effect Factor in LCIA methods

    DEFF Research Database (Denmark)

    Cosme, Nuno Miguel Dias; Bjørn, Anders; Rosenbaum, Ralph K.

    diversity. Ecosystem-related impacts are traditionally benchmarked by potential loss of biological diversity as Potentially Disappeared Fraction of species (PDF) integrated over area and time, building on the biological sensitivity of species in each receiving ecosystem. For consistency among Life Cycle...... Impact Assessment (LCIA) methods midpoint indicators are shown in Potentially Affected Fraction of species (PAF), which implicitly suggests reversibility to previous stable states. Currently applied conversion factors from midpoint to endpoint (species loss, as PDF) range from 10 (NOEC-based), 2 (chronic...... EC50-based) or 1 (assuming that continuous stress affects reproduction rate), but these are all based on biological/physiological responses and do not add a true ecological component to the impact. Such factor simply changes the HC50 by 1 or 0.3 log units. A stressor with equal intensity in two...

  10. Nonnegative matrix factorization: a blind spectra separation method for in vivo fluorescent optical imaging.

    Science.gov (United States)

    Montcuquet, Anne-Sophie; Hervé, Lionel; Navarro, Fabrice; Dinten, Jean-Marc; Mars, Jérôme I

    2010-01-01

    Fluorescence imaging in diffusive media is an emerging imaging modality for medical applications that uses injected fluorescent markers that bind to specific targets, e.g., carcinoma. The region of interest is illuminated with near-IR light and the emitted back fluorescence is analyzed to localize the fluorescence sources. To investigate a thick medium, as the fluorescence signal decreases with the light travel distance, any disturbing signal, such as biological tissues intrinsic fluorescence (called autofluorescence) is a limiting factor. Several specific markers may also be simultaneously injected to bind to different molecules, and one may want to isolate each specific fluorescent signal from the others. To remove the unwanted fluorescence contributions or separate different specific markers, a spectroscopic approach is explored. The nonnegative matrix factorization (NMF) is the blind positive source separation method we chose. We run an original regularized NMF algorithm we developed on experimental data, and successfully obtain separated in vivo fluorescence spectra.

  11. A Hyperresponsive HPA Axis May Confer Resilience Against Persistent Paclitaxel-Induced Mechanical Hypersensitivity.

    Science.gov (United States)

    Kozachik, Sharon L; Page, Gayle G

    2016-05-01

    Paclitaxel (PAC) treatment is associated with persistent, debilitating neuropathic pain that affects the hands and feet. Female sex and biological stress responsivity are risk factors for persistent pain, but it is unclear whether these important biologically based factors confer risk for PAC-induced neuropathic pain. To determine the relative contributions of sex and hypothalamic-pituitary-adrenal (HPA)-axis stress responsivity to PAC-induced mechanical hypersensitivity, we employed a PAC protocol consisting of three, 2-week cycles of every-other-day doses of PAC 1 mg/kg versus saline (Week 1) and recovery (Week 2), totaling 42 days, in mature male and female Fischer 344, Lewis, and Sprague Dawley (SD) rats, known to differ in HPA axis stress responsivity. Mechanical sensitivity was operationalized using von Frey filaments, per the up-down method. Among PAC-injected rats, SD rats exhibited significantly greater mechanical hypersensitivity relative to accumulative PAC doses compared to Fischer 344 rats. Lewis rats were not significantly different in mechanical hypersensitivity from SD or Fischer 344 rats. At the end of the protocol, PAC-injected SD rats exhibited profound mechanical hypersensitivity, whereas the PAC-injected Fischer 344 rats appeared relatively resilient to the long-term effects of PAC and exhibited mechanical sensitivity that was not statistically different from their saline-injected counterparts. Sex differences were mixed and noted only early in the PAC protocol. Moderate HPA axis stress responsivity may confer additional risk for the painful effects of PAC. If these findings hold in humans, clinicians may be better able to identify persons who may be at increased risks for developing neuropathic pain during PAC therapy.

  12. A Hyperresponsive HPA Axis May Confer Resilience Against Persistent Paclitaxel-Induced Mechanical Hypersensitivity.

    Science.gov (United States)

    Kozachik, Sharon L; Page, Gayle G

    2016-05-01

    Paclitaxel (PAC) treatment is associated with persistent, debilitating neuropathic pain that affects the hands and feet. Female sex and biological stress responsivity are risk factors for persistent pain, but it is unclear whether these important biologically based factors confer risk for PAC-induced neuropathic pain. To determine the relative contributions of sex and hypothalamic-pituitary-adrenal (HPA)-axis stress responsivity to PAC-induced mechanical hypersensitivity, we employed a PAC protocol consisting of three, 2-week cycles of every-other-day doses of PAC 1 mg/kg versus saline (Week 1) and recovery (Week 2), totaling 42 days, in mature male and female Fischer 344, Lewis, and Sprague Dawley (SD) rats, known to differ in HPA axis stress responsivity. Mechanical sensitivity was operationalized using von Frey filaments, per the up-down method. Among PAC-injected rats, SD rats exhibited significantly greater mechanical hypersensitivity relative to accumulative PAC doses compared to Fischer 344 rats. Lewis rats were not significantly different in mechanical hypersensitivity from SD or Fischer 344 rats. At the end of the protocol, PAC-injected SD rats exhibited profound mechanical hypersensitivity, whereas the PAC-injected Fischer 344 rats appeared relatively resilient to the long-term effects of PAC and exhibited mechanical sensitivity that was not statistically different from their saline-injected counterparts. Sex differences were mixed and noted only early in the PAC protocol. Moderate HPA axis stress responsivity may confer additional risk for the painful effects of PAC. If these findings hold in humans, clinicians may be better able to identify persons who may be at increased risks for developing neuropathic pain during PAC therapy. PMID:26512050

  13. A structured elicitation method to identify key direct risk factors for the management of natural resources.

    Science.gov (United States)

    Smith, Michael; Wallace, Ken; Lewis, Loretta; Wagner, Christian

    2015-11-01

    The high level of uncertainty inherent in natural resource management requires planners to apply comprehensive risk analyses, often in situations where there are few resources. In this paper, we demonstrate a broadly applicable, novel and structured elicitation approach to identify important direct risk factors. This new approach combines expert calibration and fuzzy based mathematics to capture and aggregate subjective expert estimates of the likelihood that a set of direct risk factors will cause management failure. A specific case study is used to demonstrate the approach; however, the described methods are widely applicable in risk analysis. For the case study, the management target was to retain all species that characterise a set of natural biological elements. The analysis was bounded by the spatial distribution of the biological elements under consideration and a 20-year time frame. Fourteen biological elements were expected to be at risk. Eleven important direct risk factors were identified that related to surrounding land use practices, climate change, problem species (e.g., feral predators), fire and hydrological change. In terms of their overall influence, the two most important risk factors were salinisation and a lack of water which together pose a considerable threat to the survival of nine biological elements. The described approach successfully overcame two concerns arising from previous risk analysis work: (1) the lack of an intuitive, yet comprehensive scoring method enabling the detection and clarification of expert agreement and associated levels of uncertainty; and (2) the ease with which results can be interpreted and communicated while preserving a rich level of detail essential for informed decision making. PMID:27441228

  14. A structured elicitation method to identify key direct risk factors for the management of natural resources.

    Science.gov (United States)

    Smith, Michael; Wallace, Ken; Lewis, Loretta; Wagner, Christian

    2015-11-01

    The high level of uncertainty inherent in natural resource management requires planners to apply comprehensive risk analyses, often in situations where there are few resources. In this paper, we demonstrate a broadly applicable, novel and structured elicitation approach to identify important direct risk factors. This new approach combines expert calibration and fuzzy based mathematics to capture and aggregate subjective expert estimates of the likelihood that a set of direct risk factors will cause management failure. A specific case study is used to demonstrate the approach; however, the described methods are widely applicable in risk analysis. For the case study, the management target was to retain all species that characterise a set of natural biological elements. The analysis was bounded by the spatial distribution of the biological elements under consideration and a 20-year time frame. Fourteen biological elements were expected to be at risk. Eleven important direct risk factors were identified that related to surrounding land use practices, climate change, problem species (e.g., feral predators), fire and hydrological change. In terms of their overall influence, the two most important risk factors were salinisation and a lack of water which together pose a considerable threat to the survival of nine biological elements. The described approach successfully overcame two concerns arising from previous risk analysis work: (1) the lack of an intuitive, yet comprehensive scoring method enabling the detection and clarification of expert agreement and associated levels of uncertainty; and (2) the ease with which results can be interpreted and communicated while preserving a rich level of detail essential for informed decision making.

  15. The interleukin-20 receptor axis in early rheumatoid arthritis

    DEFF Research Database (Denmark)

    Kragstrup, Tue Wenzel; Greisen, Stinne Ravn; Nielsen, Morten Aagaard;

    2016-01-01

    BACKGROUND: Rheumatoid arthritis (RA) is often characterized by the presence of rheumatoid factor, anti-citrullinated protein antibodies, and bone erosions. Current therapies can compromise immunity, leading to risk of infection. The interleukin-20 receptor (IL-20R) axis comprising IL-19, IL-20...... RA synovial fluid compared with monocytes from both RA and healthy control peripheral blood. The plasma concentrations of IL-20 and IL-24 were increased in rheumatoid factor and anti-citrullinated protein antibody positive compared with negative early RA patients (all P < 0.0001). Immune complexes...

  16. DARHT Axis-I Diode Simulations II: Geometrical Scaling

    Energy Technology Data Exchange (ETDEWEB)

    Ekdahl, Carl A. Jr. [Los Alamos National Laboratory

    2012-06-14

    Flash radiography of large hydrodynamic experiments driven by high explosives is a venerable diagnostic technique in use at many laboratories. Many of the largest hydrodynamic experiments study mockups of nuclear weapons, and are often called hydrotests for short. The dual-axis radiography for hydrodynamic testing (DARHT) facility uses two electron linear-induction accelerators (LIA) to produce the radiographic source spots for perpendicular views of a hydrotest. The first of these LIAs produces a single pulse, with a fixed {approx}60-ns pulsewidth. The second axis LIA produces as many as four pulses within 1.6-{micro}s, with variable pulsewidths and separation. There are a wide variety of hydrotest geometries, each with a unique radiographic requirement, so there is a need to adjust the radiographic dose for the best images. This can be accomplished on the second axis by simply adjusting the pulsewidths, but is more problematic on the first axis. Changing the beam energy or introducing radiation attenuation also changes the spectrum, which is undesirable. Moreover, using radiation attenuation introduces significant blur, increasing the effective spot size. The dose can also be adjusted by changing the beam kinetic energy. This is a very sensitive method, because the dose scales as the {approx}2.8 power of the energy, but it would require retuning the accelerator. This leaves manipulating the beam current as the best means for adjusting the dose, and one way to do this is to change the size of the cathode. This method has been proposed, and is being tested. This article describes simulations undertaken to develop scaling laws for use as design tools in changing the Axis-1 beam current by changing the cathode size.

  17. Contributing death factors in very low-birth-weight infants by path method analysis

    Directory of Open Access Journals (Sweden)

    Morteza Ghojazadeh

    2014-01-01

    Full Text Available Background: Neonatal deaths account for 40% of deaths under the age of 5 years worldwide. Therefore, efforts to achieve the UN Millennium Development Goal 4 of reducing childhood mortality by two-thirds by 2015 are focused on reducing neonatal deaths in high-mortality countries. The aim of present study was to determine death factors among very low-birth-weight infants by path method analysis. Materials and Methods: In this study, medical records of 2,135 infants admitted between years 2008 and 2010 in neonatal intense care unit of Alzahra Educational-Medical centre (Tabriz, Iran were analysed by path method using statistical software SPSS 18. Results: Variables such as duration of hospitalisation, birth weight, gestational age have negative effect on infant mortality, and gestational blood pressure has positive direct effect on infant mortality that at whole represented 66.5% of infant mortality variance (F = 1018, P < 0.001. Gestational age termination in the positive form through birth weight, and also gestational blood pressure in negative form through hospitalisation period had indirect effect on infant mortality. Conclusion: The results of the study indicated that the duration of low-birth-weight infant′s hospitalisation is also associated with infant′s mortality (coefficient -0.7; P < 0.001. This study revealed that among the maternal factors only gestational blood pressure was in relationship with infants′ mortality.

  18. Impact of the Choice of Normalization Method on Molecular Cancer Class Discovery Using Nonnegative Matrix Factorization

    Science.gov (United States)

    Yang, Haixuan; Seoighe, Cathal

    2016-01-01

    Nonnegative Matrix Factorization (NMF) has proved to be an effective method for unsupervised clustering analysis of gene expression data. By the nonnegativity constraint, NMF provides a decomposition of the data matrix into two matrices that have been used for clustering analysis. However, the decomposition is not unique. This allows different clustering results to be obtained, resulting in different interpretations of the decomposition. To alleviate this problem, some existing methods directly enforce uniqueness to some extent by adding regularization terms in the NMF objective function. Alternatively, various normalization methods have been applied to the factor matrices; however, the effects of the choice of normalization have not been carefully investigated. Here we investigate the performance of NMF for the task of cancer class discovery, under a wide range of normalization choices. After extensive evaluations, we observe that the maximum norm showed the best performance, although the maximum norm has not previously been used for NMF. Matlab codes are freely available from: http://maths.nuigalway.ie/~haixuanyang/pNMF/pNMF.htm. PMID:27741311

  19. Axis of Zodiacal light Near Tropic Cancer

    CERN Document Server

    Nawar, S; Mikhail, J S; Morcos, A B; Ibrahim, Alhassan I

    2014-01-01

    The axis of zodiacal lights have been obtained in blue and yellow colors using photoelectric observations of zodiacal light. These observations have been carried out at Abu Simbel Site in Egypt, in October 1975. This site lies too near to the tropic of Cancer, at which the axis of the zodiacal light cone perpendiculars to the horizon. The results show that the plane of the zodiacal light is inclined to the normal by 1.59 degrees in blue color and 1.18 degrees in yellow color. This means that there is a slight variation in zodiacal light axis with wavelength, and the axis almost coincide with the ecliptic. The present results for blue color can be considered as the first one in the world near the tropic of Cancer.

  20. A method to integrate human factors expertise into the PRA process

    International Nuclear Information System (INIS)

    In response to the recognition of need, the USNRC has initiated research directed toward the integration of human factors and hardware engineering expertise throughout the PRA process. Success in this area is perceived as vital to the overall credibility of future PRAs. That is, no matter how adequate state of knowledge single task and sequence evaluation methods are, if they are not fully exploited by qualified human factors and human reliability specialists, realistic assessments of human and hardware performance separately, and in combination, will not be achieved. Also, in response to the prevailing state of PRA, the USNRC has initiated research directed toward methods for systematically applying PRA results as a technical base to: (1) retrofit/redesign equipment-centered and personnel-centered components of commercial nuclear power plants, (2) prioritize and resolve industry-wide safety issues involving human behavior, (3) establish risk-based performance measures for monitoring the effectiveness of operations, maintainability, test and surveillance programs, and (4) establish criteria for selecting, training and licensing, and subsequently evaluating the performance of plant personnel. This paper presents a method for integrating broad-based human factors expertise into the probabilistic risk assessment (PRA)/human reliability analysis (HRA) process in a standardized manner to achieve results which: (1) provide more realistic estimates of the impact of human performance on nuclear power safety, (2) can be fully audited, (3) provide a firm technical base for equipment-centered and personnel-centered retrofit/redesign of plants enabling them to meet internally and externally imposed safety standards, and (4) yield human and hardware data capable of supporting inquiries into human performance issues which transcend the individual plant

  1. Analysis of cultural development of Isfahan city Using Factor analysis method

    Directory of Open Access Journals (Sweden)

    J.Mohammadi

    2013-01-01

    Full Text Available Extended abstract1-IntroductionCultural spaces are consideredas one of the main factors for development. Cultural development is a qualitative and valuable process that for assessing it, quantitative indicators in cultural planning are used to obtain development objectives in the pattern of goods and services. The aim of the study is to determine and analyze cultural development level and regional inequality of different districts of Isfahan using factor analysis technique. The statistical population of the study is 14 districts of Isfahan municipality. The dominant approach ofthis study is quantitative – description and analytical. In this study, 35 indices have been summarized by factor analysis method and have been reduced to 5 factors and combined in significant ones and delivered.2 – Theoretical basesThe most important objectives of spatial planning, considering limitation of resources, are optimum distributions of facilities and services among different locations in which people live. To do this,there is a need to identify different locations in terms of having different facilities and services, so that developed locations are specified and planners can proceed to do something for spatial equilibrium and reducing privileged distance between districts.The present study has been conducted to reach to an equal development in Isfahan urban districts following identifying the situation and the manner of distributing development facilities cultural selected indices in different districts.3 – DiscussionCultural development of societies is evaluated by considering the changes and improvement of its indices and measured by quantitative frames. Cultural development indices are the most important tools for cultural planning in a special district in a society. In this study, cultural development indices have been used to determine the levels of districts. By using factor analysis model, the share of influential factors in the cultural

  2. Multi-axis integrated Hall magnetic sensors

    Directory of Open Access Journals (Sweden)

    Popović Radivoje S.

    2007-01-01

    Full Text Available Conventional Hall magnetic sensors respond only to the magnetic field component perpendicular to the surface of the sensor die. Multi-axis sensing capability can be provided in the following two ways: (a by integrating magnetic flux concentrators on the die, and (b by using vertical Hall devices. Here we review the most important two-and three-axis integrated Hall magnetic sensors based on these concepts. Their applications include mapping of magnetic fields and sensing angular position.

  3. Multi-scale methods for fracture: model learning across scales, digital twinning and factors of safety

    OpenAIRE

    Bordas, Stéphane; Beex, Lars; Kerfriden, Pierre; Paladim, Daniel-Alves; Olivier, Goury; Akbari, Ahmad; Rappel, Hussein

    2015-01-01

    Authors: S. P. A. Bordas, L. A. A. Beex, P. Kerfriden, D. A. Paladim, O. Goury, A. Akbari, H. Rappel  Multi-scale methods for fracture: model learning across scales, digital twinning and factors of safety Fracture and material instabilities originate at spatial scales much smaller than that of the structure of interest: delamination, debonding, fibre breakage, cell-wall buckling, are examples of nano/micro or meso-scale mechanisms which can lead to global failure of the material and s...

  4. Evaluation of Sun Protection Factor of Zingiber officinale Roscoe Extract by Ultraviolet Spectroscopy Method

    OpenAIRE

    Manoj A. Suva

    2014-01-01

    The purpose of present study was to evaluate the sun protection factor (SPF) of aqueous and methanolic extract of rhizomes of Zingiber officinale Roscoe by ultraviolet (UV) spectroscopy method. Aqueous and Methanolic extract of rhizomes of Zingiber officinale having concentration of 200µg/ml and 400µg/ml was prepared respectively and the SPF values were evaluated by UV spectroscopy. In this study, it was found that aqueous extract of Zingiber officinale (200µg/ml) have SPF value about 1.44±0....

  5. Daily Influent Quantity Forecasting Method for Sewage Treatment Plant Considering Uncertain Factors

    Institute of Scientific and Technical Information of China (English)

    LONGTengrui; FENGYuzhao; 等

    2002-01-01

    Daily influent quantity forecasting plays an important role in sewage treatment plant design and operation.Its uncertain factors are classified into three categories including day types,weather conditions and special events,of which the latter two are consicered with a BP(Back Propagation)model.On this basis,the daily period feature is taken into account in the presented model.The data from a practical sewage treatment plant utility is employed to show the effectiveness of the method.

  6. Relating invariant linear form and local epsilon factors via global methods

    OpenAIRE

    Prasad, Dipendra

    2005-01-01

    {We use the recent proof of Jacquet's conjecture due to Harris and Kudla, and the Burger-Sarnak principle to give a proof about the relationship between the existence of trilinear forms on representations of $GL_2(k_u)$ for a non-Archimedean local field $k_u$ and local epsilon factors which was earlier proved only in the odd residue characteristic by this author. The same method gives a global proof of a theorem of Saito and Tunnell about characters of $GL_2$ using a theorem of Waldspurger ab...

  7. A systematic review of mixed methods research on human factors and ergonomics in health care.

    Science.gov (United States)

    Carayon, Pascale; Kianfar, Sarah; Li, Yaqiong; Xie, Anping; Alyousef, Bashar; Wooldridge, Abigail

    2015-11-01

    This systematic literature review provides information on the use of mixed methods research in human factors and ergonomics (HFE) research in health care. Using the PRISMA methodology, we searched four databases (PubMed, PsycInfo, Web of Science, and Engineering Village) for studies that met the following inclusion criteria: (1) field study in health care, (2) mixing of qualitative and quantitative data, (3) HFE issues, and (4) empirical evidence. Using an iterative and collaborative process supported by a structured data collection form, the six authors identified a total of 58 studies that primarily address HFE issues in health information technology (e.g., usability) and in the work of healthcare workers. About two-thirds of the mixed methods studies used the convergent parallel study design where quantitative and qualitative data were collected simultaneously. A variety of methods were used for collecting data, including interview, survey and observation. The most frequent combination involved interview for qualitative data and survey for quantitative data. The use of mixed methods in healthcare HFE research has increased over time. However, increasing attention should be paid to the formal literature on mixed methods research to enhance the depth and breadth of this research.

  8. Contraceptive Method Choice Among Newly Married Couples and Influential Factors in Shanghai Municipality

    Institute of Scientific and Technical Information of China (English)

    郭友宁; 方可娟; 施元莉; 楼超华; 林德良; 李惠沁; 张德玮

    1995-01-01

    A foliow-up study with 7,826 representative newly married couples for fifteen months after their weddings in Shanghai Municipality showed that among the 3,412 couples who actually adopted contraceptive method, rhythm was the main choice; the proportion for couples taking the contraceptive pill was much higher among sexually active couples before their weddings. The proportions of adopting rhythm or condom or the both, however, increased afterwards. About 86% of couples who had ever planned adopting the rhythm at registration actually used it. In fact, 16% of those who had ever planned to take pills eventually made this choice, because of their worry about any adverse side effects on mother's and fetus' health. Their knowledge about contraception, especially the pills, was incomprehensive. Approximately 62% of condom users had not been given any instruction regarding its use when they got this contraceptive device one year later. Half of the pill and spermicide users learnt these respective methods from their friends or relatives. The proportion of delivering contraceptives after marriage by F.P.P. was rather low. By fitting the multinomial logistic regression model, it is indicated that couple' s evaluation on contraceptive methods and contraceptive goal were the main factors determining newlyweds' method of choice. Wife's knowledge on contraception and the accessibility of contraceptives and devices also influenced the method choice to some extent.

  9. Human Factors methods concerning integrated validation of nuclear power plant control rooms

    International Nuclear Information System (INIS)

    The frame of reference for this work was existing recommendations and instructions from the NPP area, experiences from the review of the Turbic Validation and experiences from system validations performed at the Swedish Armed Forces, e.g. concerning military control rooms and fighter pilots. These enterprises are characterized by complex systems in extreme environments, often with high risks, where human error can lead to serious consequences. A focus group has been performed with representatives responsible for Human Factors issues from all Swedish NPP:s. The questions that were discussed were, among other things, for whom an integrated validation (IV) is performed and its purpose, what should be included in an IV, the comparison with baseline measures, the design process, the role of SSM, which methods of measurement should be used, and how the methods are affected of changes in the control room. The report brings different questions to discussion concerning the validation process. Supplementary methods of measurement for integrated validation are discussed, e.g. dynamic, psychophysiological, and qualitative methods for identification of problems. Supplementary methods for statistical analysis are presented. The study points out a number of deficiencies in the validation process, e.g. the need of common guidelines for validation and design, criteria for different types of measurements, clarification of the role of SSM, and recommendations for the responsibility of external participants in the validation process. The authors propose 12 measures for taking care of the identified problems

  10. Using Chebyshev polynomials and approximate inverse triangular factorizations for preconditioning the conjugate gradient method

    Science.gov (United States)

    Kaporin, I. E.

    2012-02-01

    In order to precondition a sparse symmetric positive definite matrix, its approximate inverse is examined, which is represented as the product of two sparse mutually adjoint triangular matrices. In this way, the solution of the corresponding system of linear algebraic equations (SLAE) by applying the preconditioned conjugate gradient method (CGM) is reduced to performing only elementary vector operations and calculating sparse matrix-vector products. A method for constructing the above preconditioner is described and analyzed. The triangular factor has a fixed sparsity pattern and is optimal in the sense that the preconditioned matrix has a minimum K-condition number. The use of polynomial preconditioning based on Chebyshev polynomials makes it possible to considerably reduce the amount of scalar product operations (at the cost of an insignificant increase in the total number of arithmetic operations). The possibility of an efficient massively parallel implementation of the resulting method for solving SLAEs is discussed. For a sequential version of this method, the results obtained by solving 56 test problems from the Florida sparse matrix collection (which are large-scale and ill-conditioned) are presented. These results show that the method is highly reliable and has low computational costs.

  11. Sex differences in the HPA axis.

    Science.gov (United States)

    Goel, Nirupa; Workman, Joanna L; Lee, Tiffany T; Innala, Leyla; Viau, Victor

    2014-07-01

    The hypothalamic-pituitary-adrenal (HPA) axis is a major component of the systems that respond to stress, by coordinating the neuroendocrine and autonomic responses. Tightly controlled regulation of HPA responses is critical for maintaining mental and physical health, as hyper- and hypo-activity have been linked to disease states. A long history of research has revealed sex differences in numerous components of the HPA stress system and its responses, which may partially form the basis for sex disparities in disease development. Despite this, many studies use male subjects exclusively, while fewer reports involve females or provide direct sex comparisons. The purpose of this article is to present sex comparisons in the functional and molecular aspects of the HPA axis, through various phases of activity, including basal, acute stress, and chronic stress conditions. The HPA axis in females initiates more rapidly and produces a greater output of stress hormones. This review focuses on the interactions between the gonadal hormone system and the HPA axis as the key mediators of these sex differences, whereby androgens increase and estrogens decrease HPA activity in adulthood. In addition to the effects of gonadal hormones on the adult response, morphological impacts of hormone exposure during development are also involved in mediating sex differences. Additional systems impinging on the HPA axis that contribute to sex differences include the monoamine neurotransmitters norepinephrine and serotonin. Diverse signals originating from the brain and periphery are integrated to determine the level of HPA axis activity, and these signals are, in many cases, sex-specific.

  12. UMAPRM: Uniformly sampling the medial axis

    KAUST Repository

    Yeh, Hsin-Yi Cindy

    2014-05-01

    © 2014 IEEE. Maintaining clearance, or distance from obstacles, is a vital component of successful motion planning algorithms. Maintaining high clearance often creates safer paths for robots. Contemporary sampling-based planning algorithms That utilize The medial axis, or The set of all points equidistant To Two or more obstacles, produce higher clearance paths. However, They are biased heavily Toward certain portions of The medial axis, sometimes ignoring parts critical To planning, e.g., specific Types of narrow passages. We introduce Uniform Medial Axis Probabilistic RoadMap (UMAPRM), a novel planning variant That generates samples uniformly on The medial axis of The free portion of Cspace. We Theoretically analyze The distribution generated by UMAPRM and show its uniformity. Our results show That UMAPRM\\'s distribution of samples along The medial axis is not only uniform but also preferable To other medial axis samplers in certain planning problems. We demonstrate That UMAPRM has negligible computational overhead over other sampling Techniques and can solve problems The others could not, e.g., a bug Trap. Finally, we demonstrate UMAPRM successfully generates higher clearance paths in The examples.

  13. Bouncing back - trauma and the HPA-axis in healthy adults

    Directory of Open Access Journals (Sweden)

    Ellen Renée Klaassens

    2010-12-01

    Full Text Available Dysregulation of the hypothalamic–pituitary–adrenal (HPA-axis is thought to underlie stress-related psychiatric disorders such as posttraumatic stress disorder (PTSD. Some studies have reported HPA-axis dysregulation in trauma-exposed (TE adults in the absence of psychiatric morbidity. In this dissertation we set out to unravel part of the mechanism that underlies the complex relations between trauma exposure, stress regulation, and psychopathology. Mentally healthy TE subjects were compared with non-trauma-exposed (NE healthy controls. To distinguish between the potential effects of childhood trauma and adulthood trauma, we included women exposed to childhood trauma as well as men who were exposed to trauma during adulthood. Basal HPA-axis functioning was assessed with salivary cortisol samples. HPA-axis reactivity was assessed with the dexamethasone/corticotropin-releasing hormone (Dex/CRH test. The results show that childhood trauma exposure is associated with an attenuated cortisol response after the Dex/CRH challenge test in women. In contrast, trauma exposure during adulthood was not associated with alterations in HPA-axis regulation after the Dex/CRH test. Neither childhood trauma nor adulthood trauma were associated with basal HPA-axis functioning. Childhood trauma rather than adulthood trauma may chronically affect HPA-axis functioning. Since the association between adulthood trauma and resilience to psychopathology cannot be explained by HPA-axis functioning alone, other factors must play a role.

  14. Effects of sericine on growth hormone/insulin-like growth factor-1 axis of testis in type 2 diabetes mellitus rats%丝胶对2型糖尿病大鼠睾丸生长激素/胰岛素样生长因子-1轴的作用

    Institute of Scientific and Technical Information of China (English)

    付文亮; 付秀美; 钟美蓉; 和亚强; 宋成军; 陈志宏

    2011-01-01

    目的 探讨丝胶对2型糖尿病大鼠睾丸生长激素(GH)/胰岛素样生长因子-1(IGF-1)轴的作用.方法 40只雄性SD大鼠随机分为正常对照组、糖尿病模型组、丝胶治疗组和阳性对照组,每组均为10只.链脲佐菌素连续腹腔注射制作2型糖尿病大鼠模型,1周后以血糖≥16.7mmol/L作为成模标准.待模型成功建立后,模型组大鼠不做任何处理,丝胶治疗组大鼠给予丝胶灌胃[2.4g/(kg·d)],阳性对照组大鼠给予二甲双胍[55.33mg/(kg·d)]灌胃,均为35d.采用酶联免疫吸附测定(ELISA)方法检测大鼠血清睾酮、GH和IGF-1水平;分别采用免疫组织化学染色、免疫印迹法和RT-PCR法检测睾丸GH、GH受体(GHR)和IGF-1的表达.结果 丝胶可明显降低糖尿病大鼠血GH水平、下调睾丸GH的表达,升高血IGF-1和睾酮水平,上调睾丸IGF-1和GHR的表达(P<0.05,P<0.01).并且丝胶治疗组各项指标与阳性对照组比较无明显差别(P>0.05).结论 丝胶可通过调节糖尿病时GH/IGF-1轴紊乱改善生精功能,发挥对糖尿病生殖功能损害的保护作用,其作用与二甲双胍相当.%Objective To study the effects of sericine on growth hormone(GH)/insulin-like growth factor-1 ( IGF-1 ) axis of testis in type 2 diabetes mellitus rats model.Methods Forty male SD rats were randomly divided into 4 groups (n = 10): normal control group, diabetes model group, sericine treatment group and positive control group.The type 2 diabetes model rats were induced by continuous intraperitoneal injection of streptozotocin and blood glucose≥ 16.7mmol/L was taken as the criterion one week after injection.After successfully establishing the diabetes animal models, the rats in diabetes model group were not given any more treatment, the rats in sericine treatment group were lavaged with sericine [2.4g/( kg· d), 35d], the rats in positive control group were lavaged with metformin [55.33 mg/( kg· d), 35d].ELISA was used to detect the

  15. 血管紧张素-(1-7)/M as 受体轴通过调控 NF-κB 通路保护心肌细胞对抗高糖诱导的损伤%Angiotensin-(1-7)/Mas receptor axis protects cardiomyocytes against high glucose-induced injury by modulating nuclear factor-κB pathway

    Institute of Scientific and Technical Information of China (English)

    梁伟杰; 陈景福; 宋明才; 莫利求; 潘玩莹; 李健豪; 冯鉴强; 张稳柱

    2015-01-01

    AIM:Tostudywhe ther theangiotens in-(1-7)[Ang-(1-7)]/Mas receptor axis protects cardio-myocytes against high glucose (HG)-induced injury by inhibiting nuclear factor-κB (NF-κB) pathway.METHODS:The cell viability was measured by CCK-8 assay.The intracellular levels of reactive oxygen species ( ROS) were detected by DCFH-DA staining .The number of apoptotic cells was tested by Hoechst 33258 nuclear staining .Mitochondrial membrane potential ( MMP) was examined by JC-1 staining.The levels of NF-κB p65 subunit and cleaved caspase-3 protein were de-termined by Western blotting.RESULTS: Treatment of H9c2 cardiac cells with 35 mmol/L glucose (HG) for 30, 60, 90, 120 and 150 min significantly enhanced the levels of phosphorated ( p) NF-κB p65, peaking at 60 min.Co-treatment of the cells with 1 μmol/L Ang-(1-7) and HG for 60 min attenuated the up-regulation of p-NF-κB p65 induced by HG. Co-treatment of the cells with Ang-(1-7) at concentrations of 0.1~30μmol/L and HG for 24 h inhibited HG-induced cy-totoxicity, evidenced by an increase in cell viability .On the other hand, 1 μmol/L Ang-(1-7) ameliorated HG-induced apoptosis, oxidative stress and mitochondrial damage , indicated by decreases in the number of apoptotic cells , cleaved caspase-3 level, ROS generation and MMP loss .However, the above cardioprotective effects of Ang-(1-7) were markedly blocked by A-779, an antagonist of Ang-(1-7) receptor (Mas receptor).Similarly, co-treatment of H9c2 cardiac cells with 100 μmol/L PDTC ( an inhibitor of NF-κB) and HG for 24 h also obviously reduced the above injuries induced by HG.CONCLUSION:Ang-(1-7)/Mas receptor axis prevents the cardiomyocytes from the HG-induced injury by inhibiting NF-κB pathway .%目的:探讨血管紧张素-(1-7)[Ang-(1-7)]/Mas受体轴能否通过抑制核因子-κB (NF-κB)通路对抗高糖( HG)引起的心肌细胞损伤。方法:应用细胞计数检测试剂盒( CCK-8)检测心肌细胞存活率;

  16. SCALE FACTOR DETERMINATION METHOD OF ELECTRO-OPTICAL MODULATOR IN FIBER-OPTIC GYROSCOPE

    Directory of Open Access Journals (Sweden)

    A. S. Aleynik

    2016-05-01

    Full Text Available Subject of Research. We propose a method for dynamic measurement of half-wave voltage of electro-optic modulator as part of a fiber optic gyroscope. Excluding the impact of the angular acceleration o​n measurement of the electro-optical coefficient is achieved through the use of homodyne demodulation method that allows a division of the Sagnac phase shift signal and an auxiliary signal for measuring the electro-optical coefficient in the frequency domain. Method. The method essence reduces to decomposition of step of digital serrodyne modulation in two parts with equal duration. The first part is used for quadrature modulation signals. The second part comprises samples of the auxiliary signal used to determine the value of the scale factor of the modulator. Modeling is done in standalone model, and as part of a general model of the gyroscope. The applicability of the proposed method is investigated as well as its qualitative and quantitative characteristics: absolute and relative accuracy of the electro-optic coefficient, the stability of the method to the effects of angular velocities and accelerations, method resistance to noise in actual devices. Main Results. The simulation has showed the ability to measure angular velocity changing under the influence of angular acceleration, acting on the device, and simultaneous measurement of electro-optical coefficient of the phase modulator without interference between these processes. Practical Relevance. Featured in the paper the ability to eliminate the influence of the angular acceleration on the measurement accuracy of the electro-optical coefficient of the phase modulator will allow implementing accurate measurement algorithms for fiber optic gyroscopes resistant to a significant acceleration in real devices.

  17. Integrated Evaluation Method-Based Technical and Economic Factors for International Oil Exploration Projects

    Directory of Open Access Journals (Sweden)

    Rui Guo

    2016-02-01

    Full Text Available Optimizing international oil exploration projects is one of the main challenges for oil companies in obtaining investment benefits. This paper establishes an integrated evaluation model to maximize investment benefits within the constraints of technical and economic factors, including geological factors, resource quality, geographic conditions, the investment environment, and oil contracts. The paper also proposes a dynamic calculation method of indicators’ weight associated with oil prices. The analysis describes the effects of contract terms and the investment environment on project value and quantifies the contractor income ratio for different types of contracts and the investment environment of the host country. Oil exploration projects in Africa are illustrated as examples in which the evaluation indicator Adjusted Concept Reserves (ACR is calculated for each project. The results show that remaining recoverable reserves and contract terms exert tremendous influences on ACR, and remaining recoverable reserves is the essential factor. Simultaneously, changes in oil prices lead to various rates of change in the contractor income ratio, which is determined by different fiscal terms. This study is important in helping oil companies optimize international oil projects and design reasonable investment strategies.

  18. Normalized impact factor (NIF): an adjusted method for calculating the citation rate of biomedical journals.

    Science.gov (United States)

    Owlia, P; Vasei, M; Goliaei, B; Nassiri, I

    2011-04-01

    The interests in journal impact factor (JIF) in scientific communities have grown over the last decades. The JIFs are used to evaluate journals quality and the papers published therein. JIF is a discipline specific measure and the comparison between the JIF dedicated to different disciplines is inadequate, unless a normalization process is performed. In this study, normalized impact factor (NIF) was introduced as a relatively simple method enabling the JIFs to be used when evaluating the quality of journals and research works in different disciplines. The NIF index was established based on the multiplication of JIF by a constant factor. The constants were calculated for all 54 disciplines of biomedical field during 2005, 2006, 2007, 2008 and 2009 years. Also, ranking of 393 journals in different biomedical disciplines according to the NIF and JIF were compared to illustrate how the NIF index can be used for the evaluation of publications in different disciplines. The findings prove that the use of the NIF enhances the equality in assessing the quality of research works produced by researchers who work in different disciplines.

  19. 我国海洋产业结构演化的过程研究%Analysis of Chinese Marine Industrial Structure Evolution and Optimization Based on the"Three Axis Diagram"Method

    Institute of Scientific and Technical Information of China (English)

    石秋艳

    2014-01-01

    海洋产业结构的优化升级是海洋经济健康持续发展的重要保障,并直接影响着人类未来的发展。在有关学者对海洋产业结构演化的研究基础之上,运用三轴图分析法,构建了海洋产业结构演进模式图,可直观清晰地看出我国海洋三次产业结构的动态演变过程,显示我国海洋产业结构已实现第三产业占据主导地位的三、二、一产业结构模式,并在此基础上对海洋产业结构的演化阶段进行分析。从加强国家宏观调控、优化产业布局、加强科技创新、建立人才队伍等方面提出优化海洋产业结构的对策。%Optimization and upgrading of industrial structure of the ocean is an important guarantee for develping marine economy healthly and sustainly which directly affecting the future development of mankind. Based on the research scholars of the evolution of the marine industry structure above, marine industrial structure evolution model diagram was constructed by using three-axis chart analysis.c The dynamic evolution of the industrial structure of China's three oceans can be revealed as following:The third industry has become the largest industrial sector in marine industry structure . The evolutionary stages of marine industrial structure were analyzed based on the above analysis. Finally, the marine industrial structure optimization strategies were put forward as the following:strengthening the national macro-control, optimizing the industrial layout, strengthening scientific and technological innovation, and establishing personnel.

  20. The fear-factor stress test: an ethical, non-invasive laboratory method that produces consistent and sustained cortisol responding in men and women.

    Science.gov (United States)

    du Plooy, Christopher; Thomas, Kevin G F; Henry, Michelle; Human, Robyn; Jacobs, W Jake

    2014-06-01

    We describe a method to administer a controlled, effective stressor to humans in the laboratory. The method combines the Trier Social Stress Test (TSST) and the Cold Pressor Test into a single, believable procedure called the Fear-Factor Stress Test (FFST). In the procedure, participants imagine auditioning for the reality television show Fear Factor. They stand before a video recorder and a panel of judges while (a) delivering a motivational speech, (b) performing a verbal arithmetic task, and (c) placing one hand into a bucket of ice water for up to 2 min. We measured subjective anxiety, heart rate, and salivary cortisol in three groups of young adults (n = 30 each, equal numbers of men and women): FFST, TSST, and Control (a placebo version of the FFST). Although the FFST and TSST groups were not distinguishable at the cortisol measure taken 5 min post-manipulation, at 35 min postmanipulation average cortisol levels in the TSST group had returned to baseline, whereas those in the FFST group continued to rise. The proportion of individual cortisol responders (≥ 2 nmol/l increase over baseline) in the TSST and FFST groups did not differ at the 5-min measure, but at the 35-min measure the FFST group contained significantly more responders. The findings indicate that the FFST induces a more robust and sustained cortisol response (which we assume is a marker of an HPA-axis response) than the TSST, and that it does so without increasing participant discomfort or incurring appreciably greater resource and time costs. PMID:24435939

  1. Factors influencing superimposition error of 3D cephalometric landmarks by plane orientation method using 4 reference points: 4 point superimposition error regression model.

    Science.gov (United States)

    Hwang, Jae Joon; Kim, Kee-Deog; Park, Hyok; Park, Chang Seo; Jeong, Ho-Gul

    2014-01-01

    Superimposition has been used as a method to evaluate the changes of orthodontic or orthopedic treatment in the dental field. With the introduction of cone beam CT (CBCT), evaluating 3 dimensional changes after treatment became possible by superimposition. 4 point plane orientation is one of the simplest ways to achieve superimposition of 3 dimensional images. To find factors influencing superimposition error of cephalometric landmarks by 4 point plane orientation method and to evaluate the reproducibility of cephalometric landmarks for analyzing superimposition error, 20 patients were analyzed who had normal skeletal and occlusal relationship and took CBCT for diagnosis of temporomandibular disorder. The nasion, sella turcica, basion and midpoint between the left and the right most posterior point of the lesser wing of sphenoidal bone were used to define a three-dimensional (3D) anatomical reference co-ordinate system. Another 15 reference cephalometric points were also determined three times in the same image. Reorientation error of each landmark could be explained substantially (23%) by linear regression model, which consists of 3 factors describing position of each landmark towards reference axes and locating error. 4 point plane orientation system may produce an amount of reorientation error that may vary according to the perpendicular distance between the landmark and the x-axis; the reorientation error also increases as the locating error and shift of reference axes viewed from each landmark increases. Therefore, in order to reduce the reorientation error, accuracy of all landmarks including the reference points is important. Construction of the regression model using reference points of greater precision is required for the clinical application of this model. PMID:25372707

  2. Understanding Factors that Shape Gender Attitudes in Early Adolescence Globally: A Mixed-Methods Systematic Review

    Science.gov (United States)

    Gibbs, Susannah; Blum, Robert Wm; Moreau, Caroline; Chandra-Mouli, Venkatraman; Herbert, Ann; Amin, Avni

    2016-01-01

    Background Early adolescence (ages 10–14) is a period of increased expectations for boys and girls to adhere to socially constructed and often stereotypical norms that perpetuate gender inequalities. The endorsement of such gender norms is closely linked to poor adolescent sexual and reproductive and other health-related outcomes yet little is known about the factors that influence young adolescents’ personal gender attitudes. Objectives To explore factors that shape gender attitudes in early adolescence across different cultural settings globally. Methods A mixed-methods systematic review was conducted of the peer-reviewed literature in 12 databases from 1984–2014. Four reviewers screened the titles and abstracts of articles and reviewed full text articles in duplicate. Data extraction and quality assessments were conducted using standardized templates by study design. Thematic analysis was used to synthesize quantitative and qualitative data organized by the social-ecological framework (individual, interpersonal and community/societal-level factors influencing gender attitudes). Results Eighty-two studies (46 quantitative, 31 qualitative, 5 mixed-methods) spanning 29 countries were included. Ninety percent of studies were from North America or Western Europe. The review findings indicate that young adolescents, across cultural settings, commonly express stereotypical or inequitable gender attitudes, and such attitudes appear to vary by individual sociodemographic characteristics (sex, race/ethnicity and immigration, social class, and age). Findings highlight that interpersonal influences (family and peers) are central influences on young adolescents’ construction of gender attitudes, and these gender socialization processes differ for boys and girls. The role of community factors (e.g. media) is less clear though there is some evidence that schools may reinforce stereotypical gender attitudes among young adolescents. Conclusions The findings from this

  3. A Method for Eletric Vehicle Ownership Forecast Considering Different Economic Factors

    Directory of Open Access Journals (Sweden)

    Hanwu Luo

    2013-04-01

    Full Text Available The construction of electric vehicles (EVs charging station needs to be planed according to the ownership of EVs, traffic condition, population etc. Therefore a BP neural network based method to forecast the EV ownership for a city is presented in the paper, which considers the influence on the EV ownership caused by many related economy factors, including GDP of a city, vehicle production, per capita crude steel production, per capita generation capacity, road passenger traffic, highway mileage and the total population.  A BP neural network is set up for the forecast of EV ownership, and the input layer contains seven neutrons, which represent different economic factors. There are three neurons in its hidden layer, and the output is the EV ownership.  Then the method to predict the EV ownership of a city is presented, which is based on the forecast of the civilian car ownership in a city and the country. The EV ownership in the city of Chongqing from the year 2013 to 2020 is predicted, and the accuracy of the model is verified firstly, then the EV ownership in Chongqing is obtained, which is helpful to make plans for the development of electric vehicle.

  4. Actuator assembly including a single axis of rotation locking member

    Science.gov (United States)

    Quitmeyer, James N.; Benson, Dwayne M.; Geck, Kellan P.

    2009-12-08

    An actuator assembly including an actuator housing assembly and a single axis of rotation locking member fixedly attached to a portion of the actuator housing assembly and an external mounting structure. The single axis of rotation locking member restricting rotational movement of the actuator housing assembly about at least one axis. The single axis of rotation locking member is coupled at a first end to the actuator housing assembly about a Y axis and at a 90.degree. angle to an X and Z axis providing rotation of the actuator housing assembly about the Y axis. The single axis of rotation locking member is coupled at a second end to a mounting structure, and more particularly a mounting pin, about an X axis and at a 90.degree. angle to a Y and Z axis providing rotation of the actuator housing assembly about the X axis. The actuator assembly is thereby restricted from rotation about the Z axis.

  5. Factors influencing adherence to antiretroviral treatment in Nepal: a mixed-methods study.

    Directory of Open Access Journals (Sweden)

    Sharada P Wasti

    Full Text Available BACKGROUND: Antiretroviral therapy (ART is a lifesaver for individual patients treated for Human Immunodeficiency Virus (HIV and Acquired Immune Deficiency Syndrome (AIDS. Maintaining optimal adherence to antiretroviral drugs is essential for HIV infection management. This study aimed to understand the factors influencing adherence amongst ART-prescribed patients and care providers in Nepal. METHODS: A cross-sectional mixed-methods study surveying 330 ART-prescribed patients and 34 in-depth interviews with three different types of stakeholders: patients, care providers, and key people at policy level. Adherence was assessed through survey self-reporting and during the interviews. A multivariate logistic regression model was used to identify factors associated with adherence, supplemented with a thematic analysis of the interview transcripts. RESULTS: A total of 282 (85.5% respondents reported complete adherence, i.e. no missed doses in the four-weeks prior to interview. Major factors influencing adherence were: non-disclosure of HIV status (OR = 17.99, p = 0.014; alcohol use (OR = 12.89, p = 1 hour (OR = 2.84, p = 0.035. Similarly, lack of knowledge and negative perception towards ART medications also significantly affected non-adherence. Transport costs (for repeat prescription, followed by pills running out, not wanting others to notice, side-effects, and being busy were the most common reasons for non-adherence. The interviews also revealed religious or ritual obstacles, stigma and discrimination, ART-associated costs, transport problems, lack of support, and side-effects as contributing to non-adherence. CONCLUSION: Improving adherence requires a supportive environment; accessible treatment; clear instructions about regimens; and regimens tailored to individual patients' lifestyles. Healthcare workers should address some of the practical and cultural issues around ART medicine whilst policy-makers should develop

  6. Evaluation of soybean lines and environmental stratification using the AMMI, GGE biplot, and factor analysis methods.

    Science.gov (United States)

    Sousa, L B; Hamawaki, O T; Nogueira, A P O; Batista, R O; Oliveira, V M; Hamawaki, R L

    2015-10-19

    In the final phases of new soybean cultivar development, lines are cultivated in several locations across multiple seasons with the intention of identifying and selecting superior genotypes for quantitative traits. In this context, this study aimed to study the genotype-by-environment interaction for the trait grain yield (kg/ha), and to evaluate the adaptability and stability of early-cycle soybean genotypes using the additive main effects and multiplicative interaction (AMMI) analysis, genotype main effects and genotype x environment interaction (GGE) biplot, and factor analysis methods. Additionally, the efficiency of these methods was compared. The experiments were carried out in five cities in the State of Mato Grosso: Alto Taquari, Lucas do Rio Verde, Sinop, Querência, and Rondonópolis, in the 2011/2012 and 2012/2013 seasons. Twenty-seven early-cycle soybean genotypes were evaluated, consisting of 22 lines developed by Universidade Federal de Uberlândia (UFU) soybean breeding program, and five controls: UFUS Carajás, MSOY 6101, MSOY 7211, UFUS Guarani, and Riqueza. Significant and complex genotype-by-environment interactions were observed. The AMMI model presented greater efficiency by retaining most of the variation in the first two main components (61.46%), followed by the GGE biplot model (57.90%), and factor analysis (54.12%). Environmental clustering among the methodologies was similar, and was composed of one environmental group from one location but from different seasons. Genotype G5 presented an elevated grain yield, and high adaptability and stability as determined by the AMMI, factor analysis, and GGE biplot methodologies.

  7. Peat decomposition - shaping factors, significance in environmental studies and methods of determination; a literature review

    Science.gov (United States)

    Drzymulska, Danuta

    2016-03-01

    A review of literature data on the degree of peat decomposition - an important parameter that yields data on environmental conditions during the peat-forming process, i.e., humidity of the mire surface, is presented. A decrease in the rate of peat decomposition indicates a rise of the ground water table. In the case of bogs, which receive exclusively atmospheric (meteoric) water, data on changes in the wetness of past mire surfaces could even be treated as data on past climates. Different factors shaping the process of peat decomposition are also discussed, such as humidity of the substratum and climatic conditions, as well as the chemical composition of peat-forming plants. Methods for the determination of the degree of peat decomposition are also outlined, maintaining the division into field and laboratory analyses. Among the latter are methods based on physical and chemical features of peat and microscopic methods. Comparisons of results obtained by different methods can occasionally be difficult, which may be ascribed to different experience of researchers or the chemically undefined nature of many analyses of humification.

  8. Semiactive Vibration Control for Horizontal Axis Washing Machine

    Directory of Open Access Journals (Sweden)

    Barış Can Yalçın

    2015-01-01

    Full Text Available A semiactive vibration control method is developed to cope with the dynamic stability problem of a horizontal axis washing machine. This method is based on adjusting the maximum force values produced by the semiactive suspension elements considering a washing machine’s vibration data (three axis angular position and three axis angular acceleration values in time. Before actuation signals are received by the step motors of the friction dampers, vibration data are evaluated, and then, the step motors start to narrow or expand the radius of bracelets located on the dampers. This changes the damping properties of the damper in the suspension system, and thus, the semiactive suspension system absorbs unwanted vibrations and contributes to the dynamic stability of the washing machine. To evaluate the vibration data, the angular position and angular acceleration values in three axes are defined in a function, and the maximum forces produced by semiactive suspension elements are calculated according to the gradient of this function. The relation between the dynamic stability and the walking stability is also investigated. A motion (gyroscope and accelerometer sensor is installed on the top-front panel of the washing machine because a mathematical model of a horizontal axis washing machine suggests that the walking behavior starts around this location under some assumptions, and therefore, calculating the vibrations occurring there is crucial. Semiactive damping elements are located under the left and right sides of the tub. The proposed method is tested during the spinning cycle of washing machine operation, increasing gradually from 200 rpm to 900 rpm, which produces the most challenging vibration patterns for dynamic stability. Moreover, the sound power levels produced by the washing machine are measured to evaluate the noise performance of the washing machine while the semiactive suspension system is controlled. The effectiveness of the

  9. Resonance Shift of Single-Axis Acoustic Levitation

    Institute of Scientific and Technical Information of China (English)

    XIE Wen-Jun; WEI Bing-Bo

    2007-01-01

    @@ The resonance shift due to the presence and movement of a rigid spherical sample in a single-axis acoustic levitator is studied with the boundary element method on the basis of a two-cylinder model of the levitator.The introduction of a sample into the sound pressure nodes, where it is usually levitated, reduces the resonant interval Hn (n is the mode number) between the reflector and emitter.

  10. Design and Analysis of a Novel Fully Decoupled Tri-axis Linear Vibratory Gyroscope with Matched Modes.

    Science.gov (United States)

    Xia, Dunzhu; Kong, Lun; Gao, Haiyu

    2015-01-01

    We present in this paper a novel fully decoupled silicon micromachined tri-axis linear vibratory gyroscope. The proposed gyroscope structure is highly symmetrical and can be limited to an area of about 8.5 mm × 8.5 mm. It can differentially detect three axes' angular velocities at the same time. By elaborately arranging different beams, anchors and sensing frames, the drive and sense modes are fully decoupled from each other. Moreover, the quadrature error correction and frequency tuning functions are taken into consideration in the structure design for all the sense modes. Since there exists an unwanted in-plane rotational mode, theoretical analysis is implemented to eliminate it. To accelerate the mode matching process, the particle swam optimization (PSO) algorithm is adopted and a frequency split of 149 Hz is first achieved by this method. Then, after two steps of manual adjustment of the springs' dimensions, the frequency gap is further decreased to 3 Hz. With the help of the finite element method (FEM) software ANSYS, the natural frequencies of drive, yaw, and pitch/roll modes are found to be 14,017 Hz, 14,018 Hz and 14,020 Hz, respectively. The cross-axis effect and scale factor of each mode are also simulated. All the simulation results are in good accordance with the theoretical analysis, which means the design is effective and worthy of further investigation on the integration of tri-axis accelerometers on the same single chip to form an inertial measurement unit.

  11. Simplified Method for Predicting a Functional Class of Proteins in Transcription Factor Complexes

    KAUST Repository

    Piatek, Marek J.

    2013-07-12

    Background:Initiation of transcription is essential for most of the cellular responses to environmental conditions and for cell and tissue specificity. This process is regulated through numerous proteins, their ligands and mutual interactions, as well as interactions with DNA. The key such regulatory proteins are transcription factors (TFs) and transcription co-factors (TcoFs). TcoFs are important since they modulate the transcription initiation process through interaction with TFs. In eukaryotes, transcription requires that TFs form different protein complexes with various nuclear proteins. To better understand transcription regulation, it is important to know the functional class of proteins interacting with TFs during transcription initiation. Such information is not fully available, since not all proteins that act as TFs or TcoFs are yet annotated as such, due to generally partial functional annotation of proteins. In this study we have developed a method to predict, using only sequence composition of the interacting proteins, the functional class of human TF binding partners to be (i) TF, (ii) TcoF, or (iii) other nuclear protein. This allows for complementing the annotation of the currently known pool of nuclear proteins. Since only the knowledge of protein sequences is required in addition to protein interaction, the method should be easily applicable to many species.Results:Based on experimentally validated interactions between human TFs with different TFs, TcoFs and other nuclear proteins, our two classification systems (implemented as a web-based application) achieve high accuracies in distinguishing TFs and TcoFs from other nuclear proteins, and TFs from TcoFs respectively.Conclusion:As demonstrated, given the fact that two proteins are capable of forming direct physical interactions and using only information about their sequence composition, we have developed a completely new method for predicting a functional class of TF interacting protein partners

  12. Understanding Factors that Shape Gender Attitudes in Early Adolescence Globally: A Mixed-Methods Systematic Review.

    Directory of Open Access Journals (Sweden)

    Anna Kågesten

    Full Text Available Early adolescence (ages 10-14 is a period of increased expectations for boys and girls to adhere to socially constructed and often stereotypical norms that perpetuate gender inequalities. The endorsement of such gender norms is closely linked to poor adolescent sexual and reproductive and other health-related outcomes yet little is known about the factors that influence young adolescents' personal gender attitudes.To explore factors that shape gender attitudes in early adolescence across different cultural settings globally.A mixed-methods systematic review was conducted of the peer-reviewed literature in 12 databases from 1984-2014. Four reviewers screened the titles and abstracts of articles and reviewed full text articles in duplicate. Data extraction and quality assessments were conducted using standardized templates by study design. Thematic analysis was used to synthesize quantitative and qualitative data organized by the social-ecological framework (individual, interpersonal and community/societal-level factors influencing gender attitudes.Eighty-two studies (46 quantitative, 31 qualitative, 5 mixed-methods spanning 29 countries were included. Ninety percent of studies were from North America or Western Europe. The review findings indicate that young adolescents, across cultural settings, commonly express stereotypical or inequitable gender attitudes, and such attitudes appear to vary by individual sociodemographic characteristics (sex, race/ethnicity and immigration, social class, and age. Findings highlight that interpersonal influences (family and peers are central influences on young adolescents' construction of gender attitudes, and these gender socialization processes differ for boys and girls. The role of community factors (e.g. media is less clear though there is some evidence that schools may reinforce stereotypical gender attitudes among young adolescents.The findings from this review suggest that young adolescents in different

  13. Impact of Sleep and Its Disturbances on Hypothalamo-Pituitary-Adrenal Axis Activity

    OpenAIRE

    Marcella Balbo; Rachel Leproult; Eve Van Cauter

    2010-01-01

    The daily rhythm of cortisol secretion is relatively stable and primarily under the influence of the circadian clock. Nevertheless, several other factors affect hypothalamo-pituitary-adrenal (HPA) axis activity. Sleep has modest but clearly detectable modulatory effects on HPA axis activity. Sleep onset exerts an inhibitory effect on cortisol secretion while awakenings and sleep offset are accompanied by cortisol stimulation. During waking, an association between cortisol secretory bursts and...

  14. Assessing positive matrix factorization model fit: a new method to estimate uncertainty and bias in factor contributions at the daily time scale

    Directory of Open Access Journals (Sweden)

    J. G. Hemann

    2008-02-01

    Full Text Available A Positive Matrix Factorization receptor model for aerosol pollution source apportionment was fit to a synthetic dataset simulating one year of daily measurements of ambient PM2.5 concentrations, comprised of 39 chemical species from nine pollutant sources. A novel method was developed to estimate model fit uncertainty and bias at the daily time scale, as related to factor contributions. A balanced bootstrap is used to create replicate datasets, with the same model then fit to the data. Neural networks are trained to classify factors based upon chemical profiles, as opposed to correlating contribution time series, and this classification is used to align factor orderings across results associated with the replicate datasets. Factor contribution uncertainty is assessed from the distribution of results associated with each factor. Comparing modeled factors with input factors used to create the synthetic data assesses bias. The results indicate that variability in factor contribution estimates does not necessarily encompass model error: contribution estimates can have small associated variability yet also be very biased. These results are likely dependent on characteristics of the data.

  15. Assessing positive matrix factorization model fit: a new method to estimate uncertainty and bias in factor contributions at the measurement time scale

    Directory of Open Access Journals (Sweden)

    J. G. Hemann

    2009-01-01

    Full Text Available A Positive Matrix Factorization receptor model for aerosol pollution source apportionment was fit to a synthetic dataset simulating one year of daily measurements of ambient PM2.5 concentrations, comprised of 39 chemical species from nine pollutant sources. A novel method was developed to estimate model fit uncertainty and bias at the daily time scale, as related to factor contributions. A circular block bootstrap is used to create replicate datasets, with the same receptor model then fit to the data. Neural networks are trained to classify factors based upon chemical profiles, as opposed to correlating contribution time series, and this classification is used to align factor orderings across the model results associated with the replicate datasets. Factor contribution uncertainty is assessed from the distribution of results associated with each factor. Comparing modeled factors with input factors used to create the synthetic data assesses bias. The results indicate that variability in factor contribution estimates does not necessarily encompass model error: contribution estimates can have small associated variability across results yet also be very biased. These findings are likely dependent on characteristics of the data.

  16. Effects of extraction methods and factors on leaching of metals from recycled concrete aggregates.

    Science.gov (United States)

    Bestgen, Janile O; Cetin, Bora; Tanyu, Burak F

    2016-07-01

    Leaching of metals (calcium (Ca), chromium (Cr), copper, (Cu), iron (Fe), and zinc (Zn)) of recycled concrete aggregates (RCAs) were investigated with four different leachate extraction methods (batch water leach tests (WLTs), toxicity leaching procedure test (TCLP), synthetic precipitation leaching procedure test (SPLP), and pH-dependent leach tests). WLTs were also used to perform a parametric study to evaluate factors including (i) effects of reaction time, (ii) atmosphere, (iii) liquid-to-solid (L/S) ratio, and (iv) particle size of RCA. The results from WLTs showed that reaction time and exposure to atmosphere had impact on leaching behavior of metals. An increase in L/S ratio decreased the effluent pH and all metal concentrations. Particle size of the RCA had impact on some metals but not all. Comparison of the leached concentrations of metals from select RCA samples with WLT method to leached concentrations from TCLP and SPLP methods revealed significant differences. For the same RCA samples, the highest metal concentrations were obtained with TCLP method, followed by WLT and SPLP methods. However, in all tests, the concentrations of all four (Cr, Cu, Fe, and Zn) metals were below the regulatory limits determined by EPA MCLs in all tests with few exceptions. pH-dependent batch water leach tests revealed that leaching pattern for Ca is more cationic whereas for other metals showed more amphoteric. The results obtained from the pH-dependent tests were evaluated with geochemical modeling (MINTEQA2) to estimate the governing leaching mechanisms for different metals. The results indicated that the releases of the elements were solubility-controlled except Cr. PMID:26996910

  17. Global self-esteem and method effects: competing factor structures, longitudinal invariance, and response styles in adolescents.

    Science.gov (United States)

    Urbán, Róbert; Szigeti, Réka; Kökönyei, Gyöngyi; Demetrovics, Zsolt

    2014-06-01

    The Rosenberg Self-Esteem Scale (RSES) is a widely used measure for assessing self-esteem, but its factor structure is debated. Our goals were to compare 10 alternative models for the RSES and to quantify and predict the method effects. This sample involves two waves (N =2,513 9th-grade and 2,370 10th-grade students) from five waves of a school-based longitudinal study. The RSES was administered in each wave. The global self-esteem factor with two latent method factors yielded the best fit to the data. The global factor explained a large amount of the common variance (61% and 46%); however, a relatively large proportion of the common variance was attributed to the negative method factor (34 % and 41%), and a small proportion of the common variance was explained by the positive method factor (5% and 13%). We conceptualized the method effect as a response style and found that being a girl and having a higher number of depressive symptoms were associated with both low self-esteem and negative response style, as measured by the negative method factor. Our study supported the one global self-esteem construct and quantified the method effects in adolescents.

  18. The three-isotope method for equilibrium isotope fractionation factor determination: Unfounded optimism

    Science.gov (United States)

    Cao, X.; Hayles, J. A.; Bao, H.

    2015-12-01

    The equilibrium isotope fractionation factor α is a fundamental parameter in stable isotope geochemistry. Although equilibrium α can be determined by theoretical calculation or by measurement of natural samples, direct laboratory experiments are ultimately required to verify those results. The attainment of a true exchange equilibrium in experiments is often difficult, but three methods have been devised and used to ensure that an equilibrium α has been obtained in an isotope exchange experiment. These are the two-directional method, partial-exchange method, and three-isotope method. Of these, the three-isotope method is thought to be the most rigorous. Using water-water exchange as a basic unit, we have developed a set of complex exchange models to study when and why the three-isotope method may work well or not. We found that the method cannot promise to lead to an equilibrium α before the kinetic complexity of the specific exchange experiment is known. An equilibrium point in δ17O-δ18O space can be reached only when all of the isotope exchange pathways are fully reversible, i.e. there is no mass loss at any instant, and the forward and backward reactions share the same pathway. If the exchange pathways are not fully reversible, steady state may be reached, but a steady state α can be very different from the equilibrium α. Our results validated the earlier warning that the trajectory for three-isotope evolution in δ17O-δ18O space may be a distinctly curved line or contain more than one straight line due to the non-fully reversible isotope exchange reactions. The three-isotope method for equilibrium α determination is not as rigorous or as promising as it may seem. Instead, the trajectory of three-isotope evolution provides detailed insights into the kinetics of isotope exchange between compounds. If multiple components exist in the exchange system, the δ17O-δ18O evolving trajectory would be more complex.

  19. Insulin like growth factor axis in type 1 diabetic pregnancy

    LENUS (Irish Health Repository)

    Higgins, M

    2011-02-01

    Institute of Obstetricians & Gynaecologists, RCPI Four Provinces Meeting, Junior Obstetrics & Gynaecology Society Annual Scientific Meeting, Royal Academy of Medicine in Ireland Dublin Maternity Hospitals Reports Meeting, Nov 2011

  20. Sobel Edge Detection Method to Identify and Quantify the Risk Factors for Diabetic Foot Ulcers

    Directory of Open Access Journals (Sweden)

    Allam Appa Rao

    2013-03-01

    Full Text Available Thepurpose of this studyis toidentify andquantify theneurovascular riskfactors for foot problems inpatients with diabetes mellitus, which is amajor public health concern these days.Themost feared factoramong the diabeticpatients is lower extremityamputation.Thesequence of events leading to amputation isinitiatedby ulcerationcombined with sensation loss.To prevent complications and amputations it isnecessaryto detect the foot at risk of plantar ulceration atan early stage of sensation loss.Doctors useimaging test to determine whether the plantar ulceration has spread to upper areas in the leg, andtoevaluate the size and location of the ulcer.To locate the ulceration area and assess the severity,doctor’susesanimaging technology, such as ultrasound, fluoroscopy, a computed tomography (CT or CAT scan,x-ray, or a magnetic resonance imaging (MRI test, this procedure is called asan image-guided biopsy.Toaccess the severity of foot ulcer,a new method isintroduced,whichisa popular edge detectionmethod.This method is known asSobel method, whichuses edge detection function for derivativeapproximation tofind edges. TheSobel edge methodreturns edges at those points where the gradient ofthe consideredimage is maximum,so the recognition of risk factors will be analyzed in efficient manner. Based on theseverity of foot ulcer, preventivefoot maintenance and regular foot examinations will take place in diabetespatients

  1. Risk Management method to ERP systems implementation based os critical sucess factors

    Directory of Open Access Journals (Sweden)

    Márcio Saez Caputo

    2004-10-01

    Full Text Available From the second half of years 90, the Enterprise Resource Planning (ERP systems implementation appears like one of the main investment focus related to the use of information technology in the companies, which aimed to acquire competitive advantages through cost reduction and differentiation of products with the use of these systems. ERP implementation showed to be much more than a technology project, involving structural and managing changes, becoming a complex and high risk process for the organizations. In the literature specialized on ERP, there are many examples of the difficulties of this type of project and about implementations that had not reached the expected objectives, frustrating the expectations of the contractors. The present work describes, first of all, the development of a risk management method to ERP systems implementation, based on critical success factors. Then, a case of application of the considered method is analyzed, detailing the steps and the results gotten until the moment. To the end, evidences regarding to how the method helps to improve risk management during ERP implementations are presented.

  2. The stomach-brain axis.

    Science.gov (United States)

    Holtmann, Gerald; Talley, Nicholas J

    2014-12-01

    The stomach has distinct functions in relation to the ingestion and handling of solids and liquids. These functions include storage of the food before it is gradually emptied into the duodenum, mechanical crushing of larger food particles to increase the surface area, secretion of an acidic enzyme rich gastric juice and mixing the ingested food with the gastric juice. In addition, the stomach 'senses' the composition of the gastric content and this information is passed via the vagal nerve to the lateral hypothalamus and the limbic system, most likely as palatability signals that influence eating behaviour. Other sensory qualities related to the stimulation of gastric tension receptors are satiety and fullness. Receptors that respond to macronutrient content or gastric wall tension influence appetite and meal related hormone responses. The ingestion of food - in contrast to an infusion of nutrients into the stomach - has distinct effects on the activation of specific brain regions. Brain areas such as thalamus, amygdala, putamen and praecuneus are activated by the ingestion of food. Gastric nutrient infusion evokes greater activation in the hippocampus and anterior cingulate. The brain integrates these interrelated neural and hormonal signals arising from the stomach as well as visual, olfactory and anticipatory stimuli that ultimately influence eating and other behavioural patterns. Furthermore, there is now good evidence from experimental studies that gastric afferents influence mood, and animal studies point towards the possibility that gastric dysfunction may be a risk factor for mood disorders such as anxiety and depression. The stomach is also not only colonised by Helicobacter pylori but a large array of bacteria. While there is sufficient evidence to suggest that H. pylori may alter caloric intake and mood, the role of other gastric microbiome for the brain function is unknown. To address this appropriate targeted gastric microbiome studies would be

  3. Studying the influence of pore water electrical conductivity on the formation factor, as estimated based on electrical methods

    Energy Technology Data Exchange (ETDEWEB)

    Loefgren, Martin (Kemakta Konsult AB, Stockholm (Sweden)); Vecernik, Petr; Havlova, Vaclava (Waste Disposal Dept., Nuclear Research Institute Rez plc. (Czech Republic))

    2009-11-15

    In this report the geometric formation factor, as obtained in tracer tests, is compared with the apparent formation factor, as obtained by electrical methods. This should provide information on the data uncertainty associated with the electrical methods utilised in situ within the SKB site investigation programme. Generally, if directly estimating the formation factor from the apparent formation factor, there is a risk of substantial overestimations. This is especially the case at shallow depth at the Forsmark and Oskarshamn sites, where the groundwater is of low salinity. This study is performed on nine drill core samples from the Forsmark and Oskarshamn sites. The formation factor and apparent formation factor of these samples have previously been determined by the through diffusion method, using HTO as the tracer, and by the electrical resistivity method, as part of the site investigation programme. The study is divided in two parts where part 2 was performed successfully, while part 1 suffered from problems. In part 2, eight rock samples were saturated by either a 0.05 or 0.1 M NaCl electrolyte. These electrolytes should represent the groundwater at repository depth. The formation factor of these samples was obtained by the through-electromigration (TEM) method, using iodide as the tracer. In addition, the apparent formation factors were obtained by electrical resistivity methods using direct current and alternating current at 10, 100, and 2,000 Hz. The measurements were performed in duplicates or triplicates, and generally a good reproducibility was achieved. As expected, the apparent formation factors were a few times larger than the TEM formation factor for the same sample. The ratio of the apparent formation factors and TEM formation factors range between about 2 and 12, where larger ratios were found for rock samples of low formation factors. The results were compared with modelled apparent formation factors, where input data were a range of formation

  4. IL-24 Inhibits Lung Cancer Cell Migration and Invasion by Disrupting The SDF-1/CXCR4 Signaling Axis

    OpenAIRE

    Panneerselvam, Janani; Jin, Jiankang; Shanker, Manish; Lauderdale, Jason; Bates, Jonathan; Wang, Qi; Zhao, Yan D.; Stephen J Archibald; Timothy J. Hubin; Ramesh, Rajagopal

    2015-01-01

    Background The stromal cell derived factor (SDF)-1/chemokine receptor (CXCR)-4 signaling pathway plays a key role in lung cancer metastasis and is molecular target for therapy. In the present study we investigated whether interleukin (IL)-24 can inhibit the SDF-1/CXCR4 axis and suppress lung cancer cell migration and invasion in vitro. Further, the efficacy of IL-24 in combination with CXCR4 antagonists was investigated. Methods Human H1299, A549, H460 and HCC827 lung cancer cell lines were u...

  5. Vasoactive intestinal peptide signaling axis in human leukemia

    Institute of Scientific and Technical Information of China (English)

    Glenn; Paul; Dorsam; Keith; Benton; Jarrett; Failing; Sandeep; Batra

    2011-01-01

    The vasoactive intestinal peptide (VIP) signaling axis constitutes a master "communication coordinator" between cells of the nervous and immune systems.To date,VIP and its two main receptors expressed in T lymphocytes,vasoactive intestinal peptide receptor (VPAC)1 and VPAC2,mediate critical cellular functions regulating adaptive immunity,including arresting CD4 T cells in G 1 of the cell cycle,protection from apoptosis and a potent chemotactic recruiter of T cells to the mucosa associated lymphoid compartment of the gastrointestinal tissues.Since the discovery of VIP in 1970,followed by the cloning of VPAC1 and VPAC2 in the early 1990s,this signaling axis has been associated with common human cancers,including leukemia.This review highlights the present day knowledge of the VIP ligand and its receptor expression profile in T cell leukemia and cell lines.Also,there will be a discussion describing how the anti-leukemic DNA binding transcription factor,Ikaros,regulates VIP receptor expression in primary human CD4 T lymphocytes and T cell lymphoblastic cell lines (e.g.Hut-78).Lastly,future goals will be mentioned that are expected to uncover the role of how the VIP signaling axis contributes to human leukemogenesis,and to establish whether the VIP receptor signature expressed by leukemic blasts can provide therapeutic and/or diagnostic information.

  6. Computational studies of horizontal axis wind turbines

    Science.gov (United States)

    Xu, Guanpeng

    A numerical technique has been developed for efficiently simulating fully three-dimensional viscous fluid flow around horizontal axis wind turbines (HAWT) using a zonal approach. The flow field is viewed as a combination of viscous regions, inviscid regions and vortices. The method solves the costly unsteady Reynolds averaged Navier-Stokes (RANS) equations only in the viscous region around the turbine blades. It solves the full potential equation in the inviscid region where flow is irrotational and isentropic. The tip vortices are simulated using a Lagrangean approach, thus removing the need to accurately resolve them on a fine grid. The hybrid method is shown to provide good results with modest CPU resources. A full Navier-Stokes based methodology has also been developed for modeling wind turbines at high wind conditions where extensive stall may occur. An overset grid based version that can model rotor-tower interactions has been developed. Finally, a blade element theory based methodology has been developed for the purpose of developing improved tip loss models and stall delay models. The effects of turbulence are simulated using a zero equation eddy viscosity model, or a one equation Spalart-Allmaras model. Two transition models, one based on the Eppler's criterion, and the other based on Michel's criterion, have been developed and tested. The hybrid method has been extensively validated for axial wind conditions for three rotors---NREL Phase II, Phase III, and Phase VI configurations. A limited set of calculations has been done for rotors operating under yaw conditions. Preliminary simulations have also been carried out to assess the effects of the tower wake on the rotor. In most of these cases, satisfactory agreement has been obtained with measurements. Using the numerical results from present methodologies as a guide, Prandtl's tip loss model and Corrigan's stall delay model were correlated with present calculations. An improved tip loss model has been

  7. Determining method and conditional factors of electrochemical fingerprint of Chinese traditional medicine

    Institute of Scientific and Technical Information of China (English)

    ZHANG TaiMing; LIANG YiZeng; YUAN Bin; DING Feng; ZHANG YaPeng; WEI ManQiong; CHEN Xu

    2007-01-01

    The thermodynamic systems and kinetic model suitable for the electrochemical token of the component throng in Chinese traditional medicines have been analyzed.It has been indicated that the damp oscillatory reactions in the non-equilibrium close system and open system without the supplement of dissipative substance have important significance for the throng token and analysis of chemical components in Chinese traditional medicines.Various factors influencing the electrochemical fingerprint, such as reactant species and their concentrations, electrode types, temperature, stir rate, the kind, dosage and granularity of Chinese traditional medicines, have amply been researched by the B-Z oscillatory reaction which used malonic acid as a main dissipative substance.In addition, the quantitative information about the chemical components in Chinese traditional medicines has been discussed in detail.The method and its conditions for determining the electrochemical fingerprint used in scientifically distinguishing and evaluating Chinese traditional medicines have successfully been put forward.

  8. Community Detection in Political Twitter Networks using Nonnegative Matrix Factorization Methods

    CERN Document Server

    Ozer, Mert; Davulcu, Hasan

    2016-01-01

    Community detection is a fundamental task in social network analysis. In this paper, first we develop an endorsement filtered user connectivity network by utilizing Heider's structural balance theory and certain Twitter triad patterns. Next, we develop three Nonnegative Matrix Factorization frameworks to investigate the contributions of different types of user connectivity and content information in community detection. We show that user content and endorsement filtered connectivity information are complementary to each other in clustering politically motivated users into pure political communities. Word usage is the strongest indicator of users' political orientation among all content categories. Incorporating user-word matrix and word similarity regularizer provides the missing link in connectivity only methods which suffer from detection of artificially large number of clusters for Twitter networks.

  9. Reliability Analysis of a Composite Blade Structure Using the Model Correction Factor Method

    DEFF Research Database (Denmark)

    Dimitrov, Nikolay Krasimiroy; Friis-Hansen, Peter; Berggreen, Christian

    2010-01-01

    in a probabilistic sense is model corrected so that it, close to the design point, represents the same structural behaviour as a realistic FE model. This approach leads to considerable improvement of computational efficiency over classical response surface methods, because the numerically “cheap......” idealistic model is used as the response surface, while the time-consuming detailed model is called only a few times until the simplified model is calibrated to the detailed model.......This paper presents a reliability analysis of a composite blade profile. The so-called Model Correction Factor technique is applied as an effective alternate approach to the response surface technique. The structural reliability is determined by use of a simplified idealised analytical model which...

  10. A Nonradioactive Method for Detecting DNA-binding Activity of Nuclear Transcription Factors

    Institute of Scientific and Technical Information of China (English)

    张宁; 徐永健; 张珍祥; 熊维宁

    2003-01-01

    To determine the feasibility of a nonradioactive electrophoresis mobility shift assay fordetecting nuclear transcription factor, double-stranded oligonucleotides encoding the consensus tar-get sequence of NF-κB were labled with DIG by terminal transferase. After nuclear protein stimula-ted with phorbol 12-myristate 13-acetate (PMA) or PMA and pyrrolidine dithiocarbamate (PDT C)electrophoresed on 8 % nondenaturing poliacrylamide gel together with oligeonucleotide probe, theywere electro-blotted nylon membrane positively charged. Anti-DIG-AP antibody catalyzed chemilu-minescent substrate CSPD to image on X-film. The results showed that nuclear proteins binded spe-cifically to the NF-κB consensus sequence in the EMSA by chemiluminescent technique method andthe activity of NF-κB in PMA group was more than that in PMA+PDTC group. It is suggestedthat detection of NF-κB by EMSA with chemiluminescent technique is feasible and simple, whichcan be performed in ordinary laboratories.

  11. Impact of reconstruction methods and pathological factors on survival after pancreaticoduodenectomy

    Directory of Open Access Journals (Sweden)

    Salah Binziad

    2013-01-01

    Full Text Available Background: Surgery remains the mainstay of therapy for pancreatic head (PH and periampullary carcinoma (PC and provides the only chance of cure. Improvements of surgical technique, increased surgical experience and advances in anesthesia, intensive care and parenteral nutrition have substantially decreased surgical complications and increased survival. We evaluate the effects of reconstruction type, complications and pathological factors on survival and quality of life. Materials and Methods: This is a prospective study to evaluate the impact of various reconstruction methods of the pancreatic remnant after pancreaticoduodenectomy and the pathological characteristics of PC patients over 3.5 years. Patient characteristics and descriptive analysis in the three variable methods either with or without stent were compared with Chi-square test. Multivariate analysis was performed with the logistic regression analysis test and multinomial logistic regression analysis test. Survival rate was analyzed by use Kaplan-Meier test. Results: Forty-one consecutive patients with PC were enrolled. There were 23 men (56.1% and 18 women (43.9%, with a median age of 56 years (16 to 70 years. There were 24 cases of PH cancer, eight cases of PC, four cases of distal CBD cancer and five cases of duodenal carcinoma. Nine patients underwent duct-to-mucosa pancreatico jejunostomy (PJ, 17 patients underwent telescoping pancreatico jejunostomy (PJ and 15 patients pancreaticogastrostomy (PG. The pancreatic duct was stented in 30 patients while in 11 patients, the duct was not stented. The PJ duct-to-mucosa caused significantly less leakage, but longer operative and reconstructive times. Telescoping PJ was associated with the shortest hospital stay. There were 5 postoperative mortalities, while postoperative morbidities included pancreatic fistula-6 patients, delayed gastric emptying in-11, GI fistula-3, wound infection-12, burst abdomen-6 and pulmonary infection-2. Factors

  12. [Leptin and hypothalamus-hypophysis-thyroid axis].

    Science.gov (United States)

    Riccioni, G; Menna, V; Lambo, M S; Della Vecchia, R; Di Ilio, C; De Lorenzo, A; D'Orazio, N

    2004-01-01

    The leptin system is a major regulator of food intake and metabolic rate. The leptin, an adipose tissue hormone whose plasma levels reflect energy stores, plays an important rule in the pathogenesis of such eating disorders like bulimia and anorexia. Thyroid hormones are major regulators of energy homeostasis. It is possible that leptin and thyroid hormone exert their actions on thermogenesis and energy metabolism via the same common effector patways. Leptin influences feedback regulation of the hypotalamic TRH-secreting neurons by thyroid hormone. Low serum levels of thyroid hormones reflect a dysfunction of the hypotalamic-pituitary-thyroid (HPT) and hypotalamic-pituitary-adrenal (HPA) axis in patients with nervosa anorexia. Neuroendocrine effects of leptin include effects on the HPT and HPA axis. The aim of this work is to evaluated the interactions between leptina and HPT axis on the basis of recent published works and reviews in literature. PMID:15147079

  13. Diffuser Augmented Horizontal Axis Tidal Current Turbines

    Directory of Open Access Journals (Sweden)

    Nasir Mehmood

    2012-09-01

    Full Text Available The renewal energy technologies are increasingly popular to ensure future energy sustenance and address environmental issues. The tides are enormous and consistent untapped resource of renewable energy. The growing interest in exploring tidal energy has compelling reasons such as security and diversity of supply, intermittent but predictable and limited social and environmental impacts. The tidal energy industry is undergoing an increasing shift towards diffuser augmented turbines. The reason is the higher power output of diffuser augmented turbines compared to conventional open turbines. The purpose of this study is to present a comprehensive review of diffuser augmented horizontal axis tidal current turbines. The components, relative advantages, limitations and design parameters of diffuser augmented horizontal axis tidal current turbines are presented in detail. CFD simulation of NACA 0016 airfoil is carried out to explore its potential for designing a diffuser. The core issues associated with diffuser augmented horizontal axis tidal current turbines are also discussed.

  14. New Urban Vertical Axis Wind Turbine Design

    Directory of Open Access Journals (Sweden)

    Alexandru-Mihai CISMILIANU

    2015-12-01

    Full Text Available This paper develops a different approach for enhancing the performance of Vertical Axis Wind Turbines for the use in the urban or rural environment and remote isolated residential areas. Recently the vertical axis wind turbines (VAWT have become more attractive due to the major advantages of this type of turbines in comparison to the horizontal axis wind turbines. We aim to enhance the overall performance of the VAWT by adding a second set of blades (3 x 2=6 blades following the rules of biplane airplanes. The model has been made to operate at a maximum power in the range of the TSR between 2 to 2.5. The performances of the VAWT were investigated numerically and experimentally and justify the new proposed design.

  15. Solar rotating magnetic dipole?. [around axis perpendicular to rotation axis of the sun

    Science.gov (United States)

    Antonucci, E.

    1974-01-01

    A magnetic dipole rotating around an axis perpendicular to the rotation axis of the sun can account for the characteristics of the surface large-scale solar magnetic fields through the solar cycle. The polarity patterns of the interplanetary magnetic field, predictable from this model, agree with the observed interplanetary magnetic sector structure.

  16. Psychiatric Axis I Comorbidities among Patients with Gender Dysphoria

    Directory of Open Access Journals (Sweden)

    Azadeh Mazaheri Meybodi

    2014-01-01

    Full Text Available Objectives. Cooccurring psychiatric disorders influence the outcome and prognosis of gender dysphoria. The aim of this study is to assess psychiatric comorbidities in a group of patients. Methods. Eighty-three patients requesting sex reassignment surgery (SRS were recruited and assessed through the Persian Structured Clinical Interview for DSM-IV Axis I disorders (SCID-I. Results. Fifty-seven (62.7% patients had at least one psychiatric comorbidity. Major depressive disorder (33.7%, specific phobia (20.5%, and adjustment disorder (15.7% were the three most prevalent disorders. Conclusion. Consistent with most earlier researches, the majority of patients with gender dysphoria had psychiatric Axis I comorbidity.

  17. A new vertical axis wind turbine design for urban areas

    Science.gov (United States)

    Frunzulica, Florin; Cismilianu, Alexandru; Boros, Alexandru; Dumitrache, Alexandru; Suatean, Bogdan

    2016-06-01

    In this paper we aim at developing the model of a Vertical Axis Wind Turbine (VAWT) with the short-term goal of physically realising this turbine to operate at a maximmum power of 5 kW. The turbine is designed for household users in the urban or rural areas and remote or isolated residential areas (hardly accsessible). The proposed model has a biplane configuration on each arm of the VAWT (3 × 2 = 6 blades), allowing for increased performance of the turbine at TSR between 2 and 2.5 (urban area operation) compared to the classic vertical axis turbines. Results that validate the proposed configuration as well as passive control methods to increase the performance of the classic VAWTs are presented.

  18. INTERFERENCE-FREE TOOL POSTURE GENERATION FOR 5-AXIS NC MILLING FREE-FORM SURFACES WITH CYLINDRICAL MILL

    Institute of Scientific and Technical Information of China (English)

    Chen Liping; Chen Yan; Hu Dejin

    2004-01-01

    The 5-axis NC machining offers the potential of efficient and accurate machining. However, the present CAM system for 5-axis control is still an unsolved problem due to interference between tool and surrounding objects. A new method is presented. There are two steps in this procedure. First, it detects the interference by calculating the shortest distance between the tool-axis and the surrounding surfaces. Then upon the maximum gouging, the interference-free tool posture for 5-axis NC cylindrical milling free-form surfaces is obtained by adjusting tool. The validity of the proposed method has been confirmed by machining an impeller.

  19. Survey of methods used to asses human reliability in the human factors reliability benchmark exercise

    International Nuclear Information System (INIS)

    The Joint Research Centre of the European Commission has organised a Human Factors Reliability Benchmark Exercise (HF-RBE) with the aim to assess the state-of-the-art in human reliability modelling and assessment. Fifteen teams from eleven countries, representing industry, utilities, licensing organisations and research institutes, participate in the HF-RBE, which is organised around two study cases: (1) analysis of routine functional test and maintenance procedures, with the aim to assess the probability of test-induced failures, the probability of failures to remain unrevealed, and the potential to initiate transients because of errors performed in the test; and (2) analysis of human actions during an operational transient, with the aim to assess the probability that the operators will correctly diagnose the malfunctions and take proper corrective action. The paper briefly reports how the HF-RBE was structured and gives an overview of the methods that have been used for predicting human reliability in both study cases. The experience in applying these methods is discussed and the results obtained are compared. (author)

  20. Implementation and Methods of Project Learning in Quantity Surveying Firms: Barriers, Enablers and Success Factors

    Directory of Open Access Journals (Sweden)

    Hamzah Abdul-Rahman

    2011-01-01

    Full Text Available Problem statement: Learning from project is vital for organizations to achieve competition and to survive in a dynamic environment. However, learning is not an easy task because there is no specific way for learning from projects. Besides, the practice of project learning and transfer knowledge to the firm’s level is still vague, specifically in the construction milieu. Approach: A questionnaire survey was conducted targeted quantity surveying firms in Malaysia, attempted to identify methods of learning from projects and implement this approach successfully. Interviews with experts in construction projects were conducted to expand and validate the results of the survey. Results: The findings indicated that on-the-job training is the preferable method to learn from construction project in quantity surveying firms. In addition, top management support and employee participants are the main enablers/barriers of project learning implementation. While, top management support found to be the main key success factor of project learning implementation. Conclusion/Recommendations: Determining barriers and enablers of learning showed how construction organization could implement learning from project successfully. This adds a practical tool of promoting learning in the field of organizational learning in construction. Results can be replicated in different industries to observe the disparity in each setting.

  1. Factors Affecting the Quality of Concrete Containing Solar PV Cells through Taguchi Method

    Directory of Open Access Journals (Sweden)

    Cheng An

    2015-01-01

    Full Text Available In order to comply with the implementation of sustainable development, the construction industry through the use of less polluting green energy technology is already imminent and more had to do. Production of Portland cement consumes large amount of energy and releases lots of carbon dioxide, nevertheless, the developing of sustainable society means more urgent and important to search for new cementitious materials to replace Portland cement in future constructions. The research employs Taguchi method to identify the key factors influencing the performance of alkali activated silica fume concrete in which amorphous silicon solar cells are ground and added into the mixture. Taguchi method has made valuable contributions to statistics and engineering. It provides techniques for investigating variation in experiments, system, parameter and tolerance design, all of which have been influential in improving manufactured quality. The conclusions were made thru ANOVA and F-test based on the statistical analyses. Next, we expect the inconsistence observed in the study to be further resolved by Grey Relational Analysis which is a normalization evaluation technique to solve the complicated multi-performance characteristics optimization effectively.

  2. Simplified method to predict mutual interactions of human transcription factors based on their primary structure

    KAUST Repository

    Schmeier, Sebastian

    2011-07-05

    Background: Physical interactions between transcription factors (TFs) are necessary for forming regulatory protein complexes and thus play a crucial role in gene regulation. Currently, knowledge about the mechanisms of these TF interactions is incomplete and the number of known TF interactions is limited. Computational prediction of such interactions can help identify potential new TF interactions as well as contribute to better understanding the complex machinery involved in gene regulation. Methodology: We propose here such a method for the prediction of TF interactions. The method uses only the primary sequence information of the interacting TFs, resulting in a much greater simplicity of the prediction algorithm. Through an advanced feature selection process, we determined a subset of 97 model features that constitute the optimized model in the subset we considered. The model, based on quadratic discriminant analysis, achieves a prediction accuracy of 85.39% on a blind set of interactions. This result is achieved despite the selection for the negative data set of only those TF from the same type of proteins, i.e. TFs that function in the same cellular compartment (nucleus) and in the same type of molecular process (transcription initiation). Such selection poses significant challenges for developing models with high specificity, but at the same time better reflects real-world problems. Conclusions: The performance of our predictor compares well to those of much more complex approaches for predicting TF and general protein-protein interactions, particularly when taking the reduced complexity of model utilisation into account. © 2011 Schmeier et al.

  3. Axis-Exchanged Compensation and Gait Parameters Analysis for High Accuracy Indoor Pedestrian Dead Reckoning

    Directory of Open Access Journals (Sweden)

    Honghui Zhang

    2015-01-01

    Full Text Available Pedestrian dead reckoning (PDR is an effective way for navigation coupled with GNSS (Global Navigation Satellite System or weak GNSS signal environment like indoor scenario. However, indoor location with an accuracy of 1 to 2 meters determined by PDR based on MEMS-IMU is still very challenging. For one thing, heading estimation is an important problem in PDR because of the singularities. For another thing, walking distance estimation is also a critical problem for pedestrian walking with randomness. Based on the above two problems, this paper proposed axis-exchanged compensation and gait parameters analysis algorithm to improve the navigation accuracy. In detail, an axis-exchanged compensation factored quaternion algorithm is put forward first to overcome the singularities in heading estimation without increasing the amount of computation. Besides, real-time heading is updated by R-adaptive Kalman filter. Moreover, gait parameters analysis algorithm can be divided into two steps: cadence detection and step length estimation. Thus, a method of cadence classification and interval symmetry is proposed to detect the cadence accurately. Furthermore, a step length model adjusted by cadence is established for step length estimation. Compared to the traditional PDR navigation, experimental results showed that the error of navigation reduces 32.6%.

  4. H∞ controller design for a 4-meter direct-drive azimuth axis

    Science.gov (United States)

    Chen, Li-Yan; Zhang, Zhen-Chao; Song, Xiao-Li; Wang, Da-Xing

    2015-11-01

    To pursue a higher imaging resolution for exploring more details in the information conveyed by the Universe, the next generation of optical telescopes based on a direct drive widely employ the extremely large aperture structure, which also introduces more disturbances and uncertain factors to the control system. Facing this new challenge, the PID control method in main-axis control systems of traditional astronomical telescopes cannot suffice for the requirement of the tracking precision and disturbance sensitivity in angular velocity. To overcome this shortcoming, we establish a dynamic model and propose an H∞ controller for a 4-meter azimuth direct drive control system that consists of a revolving platform (azimuth axis), a three-phase torque motor, a motor drive, an encoder, a data acquisition card and a small computers. Simulations are carried out to analyze the model and guide the real experiments. Experimental results show that the proposed H∞ controller reduces the tracking error by a maximum of 80.69% (average 57.8%) and the disturbance sensitivity by a maximum of 82.3% (average 50.96%) compared with the traditional tuned PI controller; furthermore, the order of the model describing the proposed controller can be reduced to three, thus its feasibility in real systems is guaranteed.

  5. Interaction between tumor necrosis factor, type Ⅰ interferon and the interleukin-23/17 axis in psoriasis%肿瘤坏死因子、Ⅰ型干扰素及白细胞介素23/17轴在银屑病的交互作用

    Institute of Scientific and Technical Information of China (English)

    张加芬; 李新宇

    2016-01-01

    Psoriasis is a chronic recurrent inflammatory skin disease.Although the exact pathogenesis of psoriasis remains unclear,current evidence has indicated that it is associated with immunity.Both genetic and immunological researches demonstrate that the occurrence and maintenance of psoriasis involve a variety of cells,molecules and signaling pathways.Thus,single-targeted therapies seem not to be able to completely block the complex pathophysiologic processes of psoriasis,and may cause imbalance between cytokines in immune system of patients.Tumor necrosis factor (TNF),type Ⅰ interferon (IFN) and the interleukin (IL)-23/ 17 axis are important factors involved in the pathogenesis of psoriasis,and interact with each other in the development of psoriasis.%银屑病是一种慢性复发性炎症性皮肤病,其发病的确切机制虽未完全阐明,但已有的证据表明与免疫相关.遗传学和免疫学研究表明,银屑病的发展和维持涉及多种细胞、多个分子和多条通路.因此,单一的靶向治疗似乎不能完全阻断其复杂的病理生理过程,而且可能引起患者免疫系统细胞因子间的不平衡.肿瘤坏死因子、Ⅰ型干扰素以及白细胞介素23/17轴是银屑病发病相关的重要因子,3种细胞因子在疾病过程中呈交互影响.

  6. Bayesian methods for uncertainty factor application for derivation of reference values.

    Science.gov (United States)

    Simon, Ted W; Zhu, Yiliang; Dourson, Michael L; Beck, Nancy B

    2016-10-01

    In 2014, the National Research Council (NRC) published Review of EPA's Integrated Risk Information System (IRIS) Process that considers methods EPA uses for developing toxicity criteria for non-carcinogens. These criteria are the Reference Dose (RfD) for oral exposure and Reference Concentration (RfC) for inhalation exposure. The NRC Review suggested using Bayesian methods for application of uncertainty factors (UFs) to adjust the point of departure dose or concentration to a level considered to be without adverse effects for the human population. The NRC foresaw Bayesian methods would be potentially useful for combining toxicity data from disparate sources-high throughput assays, animal testing, and observational epidemiology. UFs represent five distinct areas for which both adjustment and consideration of uncertainty may be needed. NRC suggested UFs could be represented as Bayesian prior distributions, illustrated the use of a log-normal distribution to represent the composite UF, and combined this distribution with a log-normal distribution representing uncertainty in the point of departure (POD) to reflect the overall uncertainty. Here, we explore these suggestions and present a refinement of the methodology suggested by NRC that considers each individual UF as a distribution. From an examination of 24 evaluations from EPA's IRIS program, when individual UFs were represented using this approach, the geometric mean fold change in the value of the RfD or RfC increased from 3 to over 30, depending on the number of individual UFs used and the sophistication of the assessment. We present example calculations and recommendations for implementing the refined NRC methodology.

  7. Calculation of the thermal disadvantage factor for a reactor cell with anisotropic scattering by the Fn method

    International Nuclear Information System (INIS)

    The F sub(N) method is used for the calculation of the thermal disadvantage factor in reactor cells with anisotropic scattering in the moderator. Numerical results were obtained for several reactor cells and compared with the results obtained by other methods. The results confirmed the physical conclusion, that the higher order terms in the expansion of the scattering law have an insignificant effect on the thermal disadvantage factor. (E.G.)

  8. Resonance acceptor states in single-axis deformed semiconductors

    CERN Document Server

    Odnoblyudov, M A; Yassievich, I N

    2002-01-01

    The new approach is proposed to the resonance state parameters, making it possible to determine also the probabilities of the resonance scattering and capture probability into the resonance state. It is based on the application of the Fano configuration interaction method. Two different Hamiltonians of the zero approximation are applied for the continuum states and local priming state. The wave functions are plotted by the method, accepted in the common scattering theory. The detailed consideration and concrete calculations for the acceptor resonance states in the single-axis deformed germanium by the pressure along the axes [001] and [111] are carried out

  9. [Retrieval of tropospheric NO2 by multi axis differential optical absorption spectroscopy].

    Science.gov (United States)

    Xu, Jin; Xie, Pin-hua; Si, Fu-qi; Dou, Ke; Li, Ang; Liu, Yu; Liu, Wen-qing

    2010-09-01

    A method of retrieving NO2 in troposphere based on multi axis differential optical absorption spectroscopy (MAX-DOAS) was introduced. The differential slant column density (dSCD) of NO2 was evaluated by differential optical absorption spectroscopy (DOAS), removing the Fraunhofer structure and Ring effect. Combining the results of different observing directions, the tropospheric NO2 differential slant column density (deltaSCD) was evaluated, and the air mass factor (AMF) was calculated with the radiative transfer model SCIATRAN and the tropospheric NO2 vertical column density (VCD) was retrieved. To ensure the accuracy of the results, it was compared with the results of long path differential optical absorption spectroscopy (LP-DOAS), a good accordance was shown with the correlation coefficients of 0.94027 and 0.96924. PMID:21105419

  10. Triple-axis spectrometer DruechaL

    Energy Technology Data Exchange (ETDEWEB)

    Buehrer, W.; Keller, P. [Lab. for Neutron Scattering ETH Zurich, Zurich (Switzerland) and Paul Scherrer Institute, Villigen (Switzerland)

    1996-11-01

    DruechaL is a triple-axis spectrometer located at a cold guide. The characteristics of guide and instrument allow the use of a broad spectral range of neutrons. The resolution in momentum and energy transfer can be tuned to match the experimental requirements by using either collimators or focusing systems (monochromator, antitrumpet, analyser). (author) figs., tabs., refs.

  11. The Trading Axis in Irkutsk Downtown

    Directory of Open Access Journals (Sweden)

    Elena Grigoryeva

    2015-12-01

    Full Text Available The article reveals a linear concentration of the trading function in the historical center of Irkutsk. It features historical prerequisites and continuation of the tradition in the post-Soviet period, given the conversion of plants and factories. The article analyses the current state and prospects of modernization of the trading axis with its transformation into a modern public space.

  12. Fibrous dysplasia in axis treated with vertebroplasty

    Directory of Open Access Journals (Sweden)

    Kadir Kotil

    2010-01-01

    Full Text Available Vertebroplasty of the axis is a challenging procedure, and little is known about its therapeutic outcome. Cervical fibrous dysplasia with a distinct cyst is a rare entity and few cases have been reported in the literature. A 55-year-old man with fibrous dysplasia of axis presented with severe neck pain and left arm since six months. Computed tomography and magnetic resonance imaging revealed an expansile, destructive lesion involving the axis, and no spinal cord. He was submitted to retropharyngeal surgery and the lesion was fulled by vertebroplasty. Microscopic examination was consistent with the diagnosis of monostotic fibrous dysplasia. After the surgery no recurrence was observed. The patient had remarkable improvement in clinical relief of neck pain at 1-year follow-up. Although there are descriptions of vertebral fibrous dysplasia, this is the 13th case of monostotic fibrous dysplasia of the cervical spine, and the 3rd case of the axis described in the literature. The unique case who had treated with ope vertebroplasty.

  13. Horizontal Axis Levitron--A Physics Demonstration

    Science.gov (United States)

    Michaelis, Max M.

    2014-01-01

    After a brief history of the Levitron, the first horizontal axis Levitron is reported. Because it is easy to operate, it lends itself to educational physics experiments and analogies. Precession and nutation are visualized by reflecting the beam from a laser pointer off the "spignet". Precession is fundamental to nuclear magnetic…

  14. Tennis Rackets and the Parallel Axis Theorem

    Science.gov (United States)

    Christie, Derek

    2014-01-01

    This simple experiment uses an unusual graph straightening exercise to confirm the parallel axis theorem for an irregular object. Along the way, it estimates experimental values for g and the moment of inertia of a tennis racket. We use Excel to find a 95% confidence interval for the true values.

  15. Research of 3D Iaser Scanning Based On SingIe-axis Searching Method%单坐标轴搜索法在三维激光扫描中的应用

    Institute of Scientific and Technical Information of China (English)

    辛成章; 董阳阳; 李冬平

    2015-01-01

    This paper used a single axes searching method to gain the information of K-nearest neighbors of the points reserved,simplifies the other points according to the curvature and the proportion of re-served points in their K-nearest neighbors.The sesult shows that the method can quickly and effectively simplify the point cloud data at the same time to maintain the original features.%本文采用单坐标轴搜索方法快速确定点云的k紧邻信息,然后在保留所有边界点的基础上,结合测点的曲率特征以及k邻域内保留点的情况对点云进行非均匀化。结果表明,该方法能够在快速、有效地简化点云数据的同时保持原始特征信息。

  16. Evaluation of a Blade Force Measurement System for a Vertical Axis Wind Turbine Using Load Cells

    OpenAIRE

    Morgan Rossander; Eduard Dyachuk; Senad Apelfröjd; Kristian Trolin; Anders Goude; Hans Bernhoff; Sandra Eriksson

    2015-01-01

    Unique blade force measurements on an open site straight-bladed vertical axis wind turbine have been performed. This paper presents a method for measuring the tangential and normal forces on a 12-kW vertical axis wind turbine prototype with a three-bladed H-rotor. Four single-axis load cells were installed in-between the hub and the support arms on one of the blades. The experimental setup, the measurement principle, together with the necessary control and measurement system are described. Th...

  17. Global self-esteem and method effects: competing factor structures, longitudinal invariance and response styles in adolescents

    OpenAIRE

    Urbán, Róbert; Szigeti, Réka; Kökönyei, Gyöngyi; Demetrovics, Zsolt

    2014-01-01

    The Rosenberg Self-Esteem Scale (RSES) is a widely used measure for assessing self-esteem, but its factor structure is debated. Our goals were to compare 10 alternative models for RSES; and to quantify and predict the method effects. This sample involves two waves (N=2513 ninth-grade and 2370 tenth-grade students) from five waves of a school-based longitudinal study. RSES was administered in each wave. The global self-esteem factor with two latent method factors yielded the best fit to the da...

  18. Comparative evaluation of Jatropha curcas L. seed meals obtained by different methods of defatting on toxic, antinutritional and nutritive factors

    OpenAIRE

    Xiao, Jianhui; Zhang, Hui

    2011-01-01

    Different methods of defatting have a great impact on toxic, antinutritional and nutritive factors in the oilseed meals. In order to find the most suitable methods of defatting for Jatropha curcas seed meals, the Jatropha curcas L. seed meals, defatted by Soxhlet extraction and screw-press were characterized for their toxic, anti-nutritional and nutrient factors in this study. The toxins (phorbolesters, 3.1 and 2.9 mg/g) and some anti-nutritional factors (saponins, 2.9 and 2.6%; phytates, 11....

  19. Noise estimation for off-axis electron holography

    Energy Technology Data Exchange (ETDEWEB)

    Röder, Falk, E-mail: Falk.Roeder@Triebenberg.de [Triebenberg Labor, Institut für Strukturphysik, Technische Universität Dresden, D-01062 Dresden (Germany); Lubk, Axel; Wolf, Daniel [Triebenberg Labor, Institut für Strukturphysik, Technische Universität Dresden, D-01062 Dresden (Germany); Niermann, Tore [Institut für Optik und Atomare Physik, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin (Germany)

    2014-09-15

    Off-axis electron holography provides access to the phase of the elastically scattered wave in a transmission electron microscope at scales ranging from several hundreds of nanometres down to 0.1 nm. In many cases the reconstructed phase shift is directly proportional to projected electric and magnetic potentials rendering electron holography a useful and established characterisation method for materials science. However, quantitative interpretation of experimental phase shifts requires quantitative knowledge about the noise, which has been previously established for some limiting cases only. Here, we present a general noise transfer formalism for off-axis electron holography allowing to compute the covariance (noise) of reconstructed amplitude and phase from characteristic detector functions and general properties of the reconstruction process. Experimentally, we verify the presented noise transfer formulas for two different cameras with and without objects within the errors given by the experimental noise determination. - Highlights: • We derive a general noise transfer for the off-axis holographic reconstruction. • Noise transfer formulas given by F. Lenz are included as a special case. • We estimate the covariance of a hologram using the noise spread function. • We experimentally verify the derived noise transfer formulas.

  20. Update on stress and depression: the role of the hypothalamic-pituitary-adrenal (HPA axis

    Directory of Open Access Journals (Sweden)

    Mello Andrea de Abreu Feijó de

    2003-01-01

    Full Text Available Over the past 50 years, relationships between stress and the neurobiological changes seen in psychiatric disorders have been well-documented. A major focus of investigations in this area has been the role of the hypothalamic-pituitary-adrenal (HPA axis, both as a marker of stress response and as a mediator of additional downstream pathophysiologic changes. This review examines the emerging literature concerning the relationship between stress, HPA axis function, and depression, as well as the role of early life stress as an important risk factor for HPA axis dysregulation. The more recent studies reviewed suggest that the prominence of HPA axis hyperactivity in adults with depressive and anxiety disorders may constitute a link between the occurrence of adversity in childhood and the development of adult psychopathology

  1. Development and Factor Analysis of an Instrument to Measure Preservice Teachers' Perceptions of Learning Objects

    Science.gov (United States)

    Sahin, Sami

    2010-01-01

    The purpose of this study was to develop a questionnaire to measure student teachers' perception of digital learning objects. The participants included 308 voluntary senior students attending courses in a college of education of a public university in Turkey. The items were extracted to their related factors by the principal axis factoring method.…

  2. Identification and characterization of HPA-axis reactivity endophenotypes in a cohort of female PTSD patients.

    Science.gov (United States)

    Zaba, Monika; Kirmeier, Thomas; Ionescu, Irina A; Wollweber, Bastian; Buell, Dominik R; Gall-Kleebach, Dominique J; Schubert, Christine F; Novak, Bozidar; Huber, Christine; Köhler, Katharina; Holsboer, Florian; Pütz, Benno; Müller-Myhsok, Bertram; Höhne, Nina; Uhr, Manfred; Ising, Marcus; Herrmann, Leonie; Schmidt, Ulrike

    2015-05-01

    Analysis of the function of the hypothalamic-pituitary-adrenal (HPA)-axis in patients suffering from posttraumatic stress disorder (PTSD) has hitherto produced inconsistent findings, inter alia in the Trier Social Stress Test (TSST). To address these inconsistencies, we compared a sample of 23 female PTSD patients with either early life trauma (ELT) or adult trauma (AT) or combined ELT and AT to 18 age-matched non-traumatized female healthy controls in the TSST which was preceded by intensive baseline assessments. During the TSST, we determined a variety of clinical, psychological, endocrine and cardiovascular parameters as well as expression levels of four HPA-axis related genes. Using a previously reported definition of HPA-axis responsive versus non-responsive phenotypes, we identified for the first time two clinically and biologically distinct HPA-axis reactivity subgroups of PTSD. One subgroup ("non-responders") showed a blunted HPA-axis response and distinct clinical and biological characteristics such as a higher prevalence of trauma-related dissociative symptoms and of combined AT and ELT as well as alterations in the expression kinetics of the genes encoding for the mineralocorticoid receptor (MR) and for FK506 binding protein 51 (FKBP51). Interestingly, this non-responder subgroup largely drove the relatively diminished HPA axis response of the total cohort of PTSD patients. These findings are limited by the facts that the majority of patients was medicated, by the lack of traumatized controls and by the relatively small sample size. The here for the first time identified and characterized HPA-axis reactivity endophenotypes offer an explanation for the inconsistent reports on HPA-axis function in PTSD and, moreover, suggest that most likely other factors than HPA-axis reactivity play a decisive role in determination of PTSD core symptom severity.

  3. Weight Function Method for Stress Intensity Factor of Internal Surface Semi-elliptical Crack in Elliptical Holes

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The hatches for inspecting are usually designed with elliptical holes in airplane structures, so computation of the stress intensity factor of three dimensional crack at elliptical holes is pivotal for damage tolerance analysis of these structures. In this paper, weight function is derived for a two dimensional through cracks at elliptical holes by applying a compounding method. Stress intensity factor formulas for an internal surface semi-elliptical crack in elliptical holes are obtained using the three dimensional weight function method. Stress intensity factors for an internal surface semi-elliptical crack in elliptical holes under remote tension are computed. At the same time, research on how radius of curvature for elliptical holes affect stress intensity factors was conducted. Stress intensity factors decrease when radius of curvature increases. Some results and conclusions which are of practical value are given.

  4. Study on estimate method of wave velocity and quality factor to fault seals

    Institute of Scientific and Technical Information of China (English)

    LI Zhensheng; LIU Deliang; LIU Bo; YANG Qiang; LI Jingming

    2005-01-01

    Based on ultrasonic test of fault rocks, the responses for wave velocity and quality factor (Q value) to lithology, porosity and permeability of fault rocks and mechanical property of faults are studied. In this paper, a new quantitative estimate method of fault seals is originally offered. The conclusions are as follows: (1) Wave velocity and Q value increase and porosity decreases with the increase in stress perpendicular to joint; (2) In compressive and compresso-shear fault rocks that are obviously anisotropic compared with their original rocks, the wave velocity and Q value are greater in the direction parallel with foliation, and usually less perpendicular to it. In tensile and tenso-shear fault rocks that are not obviously anisotropic, the wave velocity and Q value are under that of original rocks; (3) In foliated fault rocks, the direction with minimal wave velocity and Q value is the best direction for sealing; on the contrary it is the best for flowing; (4) Structural factures develop mainly along foliation, the minimal wave velocity and Q value reflect the flowing capacity in parallel direction to foliation, and the maximal wave velocity as well as Q value reflect the sealing capacity in normal direction to foliation. The new estimate method is based upon contrast of wave velocity and Q value between fault rocks and their original rocks, and is divided into three parts that are respectively to identify rock's lithology, to judge mechanic property of faults and to Judge sealing capacity of faults. Although there is vast scale effect between ultrasonic wave and seismic wave, they have similar regularity of response to fabric and porosity of faults. This research offers new application for seismic data and petrophysical basis for seismological estimation of fault seals. The estimate precision will be improved with the enhancement of three-dimensional seismic prospecting work.

  5. Chronic stress suppresses the expression of cutaneous hypothalamic-pituitary-adrenocortical axis elements and melanogenesis.

    Directory of Open Access Journals (Sweden)

    Silin Pang

    Full Text Available Chronic stress can affect skin function, and some skin diseases might be triggered or aggravated by stress. Stress can activate the central hypothalamic-pituitary-adrenocortical (HPA axis, which causes glucocorticoid levels to increase. The skin has HPA axis elements that react to environmental stressors to regulate skin functions, such as melanogenesis. This study explores the mechanism whereby chronic stress affects skin pigmentation, focusing on the HPA axis, and investigates the role of glucocorticoids in this pathway. We exposed C57BL/6 male mice to two types of chronic stress, chronic restraint stress (CRS and chronic unpredictable mild stress (CUMS. Mice subjected to either stress condition showed reduced melanogenesis. Interestingly, CRS and CUMS triggered reductions in the mRNA expression levels of key factors involved in the HPA axis in the skin. In mice administered corticosterone, decreased melanin synthesis and reduced expression of HPA axis elements were observed. The reduced expression of HPA axis elements and melanogenesis in the skin of stressed mice were reversed by RU486 (a glucocorticoid receptor antagonist treatment. Glucocorticoids had no significant inhibitory effect on melanogenesis in vitro. These results suggest that, high levels of serum corticosterone induced by chronic stress can reduce the expression of elements of the skin HPA axis by glucocorticoid-dependent negative feedback. These activities can eventually result in decreased skin pigmentation. Our findings raise the possibility that chronic stress could be a risk factor for depigmentation by disrupting the cutaneous HPA axis and should prompt dermatologists to exercise more caution when using glucocorticoids for treatment.

  6. Modeling factors influencing the demand for emergency department services in ontario: a comparison of methods

    Directory of Open Access Journals (Sweden)

    Meaney Christopher

    2011-08-01

    Full Text Available Abstract Background Emergency departments are medical treatment facilities, designed to provide episodic care to patients suffering from acute injuries and illnesses as well as patients who are experiencing sporadic flare-ups of underlying chronic medical conditions which require immediate attention. Supply and demand for emergency department services varies across geographic regions and time. Some persons do not rely on the service at all whereas; others use the service on repeated occasions. Issues regarding increased wait times for services and crowding illustrate the need to investigate which factors are associated with increased frequency of emergency department utilization. The evidence from this study can help inform policy makers on the appropriate mix of supply and demand targeted health care policies necessary to ensure that patients receive appropriate health care delivery in an efficient and cost-effective manner. The purpose of this report is to assess those factors resulting in increased demand for emergency department services in Ontario. We assess how utilization rates vary according to the severity of patient presentation in the emergency department. We are specifically interested in the impact that access to primary care physicians has on the demand for emergency department services. Additionally, we wish to investigate these trends using a series of novel regression models for count outcomes which have yet to be employed in the domain of emergency medical research. Methods Data regarding the frequency of emergency department visits for the respondents of Canadian Community Health Survey (CCHS during our study interval (2003-2005 are obtained from the National Ambulatory Care Reporting System (NACRS. Patients' emergency department utilizations were linked with information from the Canadian Community Health Survey (CCHS which provides individual level medical, socio-demographic, psychological and behavioral information for

  7. COMPUTATION OF STRESS INTENSITY FACTORS BY THE SUB-REGION MIXED FINITE ELEMENT METHOD OF LINES

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Based on the sub-region generalized variational principle, a sub-region mixed verposed in this paper for accurate and efficient computation of stress intensity factors (SIFs) of two-dimensional notches/cracks. The circular regions surrounding notch/crack tips are taken as the complementary energy region in which a number of leading terms of singular solutions for stresses are used, with the sought SIFs being among the unknown coefficients. The rest of the arbitrary domain is taken as the potential energy region in which FEMOL is applied to obtain approximate displacements. A mixed system of ordinary differential equations (ODEs) and algebraic equations is derived via the sub-region generalized variational principle. A singularity removal technique that eliminates the stress parameters from the mixed equation system eventually yields a standard FEMOL ODE system, the solution of which is no longer singular and is simply and efficiently obtained using a standard general-purpose ODE solver. A number of numerical examples, including bi-material notches/cracks in anti-plane and plane elasticity, are given to show the generally excellent performance of the proposed method.

  8. METHOD TO CALCULATE STRESS INTENSITY FACTOR OF V-NOTCH IN BI-MATERIALS

    Institute of Scientific and Technical Information of China (English)

    Youtang Li; Ming Song

    2008-01-01

    Based on Zak's stress function,the eigen-equation of stress singularity of bi-materials with a Ⅴ-notch was obtained.A new definition of stress intensity factor for a perpendicular inter facial Ⅴ-notch of bi-material was put forward.The effects of shear modulus and Poisson's ratio of the matrix material and attaching material on eigen-values were analyzed.A generalized ex pression for calculating KI of the perpendicular V-notch of bi-materials was obtained by means of stress extrapolation.Effects of notch depth,notch angle and Poisson's ratio of materials on the singular stress field near the tip of the Ⅴ-notch were analyzed systematically with numerical simulations.As an example,a finite plate with double edge notches under uniaxial uniform ten sion was calculated by the method presented and the influence of the notch angle and Poisson's ratio on the stress singularity near the tip of notch was obtained.

  9. Paper Similarity Detection Method Based on Distance Matrix Model with Row-Column Order Penalty Factor

    Directory of Open Access Journals (Sweden)

    Jun Li

    2014-08-01

    Full Text Available Paper similarity detection depends on grammatical and semantic analysis, word segmentation, similarity detection, document summarization and other technologies, involving multiple disciplines. However, there are some problems in the existing main detection models, such as incomplete segmentation preprocessing specification, impact of the semantic orders on detection, near-synonym evaluation, difficulties in paper backtrack and etc. Therefore, this paper presents a two-step segmentation model of special identifier and Sharpley value specific to above problems, which can improve segmentation accuracy. In the aspect of similarity comparison, a distance matrix model with row-column order penalty factor is proposed, which recognizes new words through search engine exponent. This model integrates the characteristics of vector detection, hamming distance and the longest common substring and carries out detection specific to near-synonyms, word deletion and changes in word order by redefining distance matrix and adding ordinal measures, making sentence similarity detection in terms of semantics and backbone word segmentation more effective. Compared with the traditional paper similarity retrieval, the present method has advantages in accuracy of word segmentation, low computation, reliability and high efficiency, which is of great academic significance in word segmentation, similarity detection and document summarization.

  10. Evaluation of Sun Protection Factor of Zingiber officinale Roscoe Extract by Ultraviolet Spectroscopy Method

    Directory of Open Access Journals (Sweden)

    Manoj A. Suva

    2014-03-01

    Full Text Available The purpose of present study was to evaluate the sun protection factor (SPF of aqueous and methanolic extract of rhizomes of Zingiber officinale Roscoe by ultraviolet (UV spectroscopy method. Aqueous and Methanolic extract of rhizomes of Zingiber officinale having concentration of 200µg/ml and 400µg/ml was prepared respectively and the SPF values were evaluated by UV spectroscopy. In this study, it was found that aqueous extract of Zingiber officinale (200µg/ml have SPF value about 1.44±0.034 and aqueous extract of Zingiber officinale (400µg/ml haveSPF value about 1.82±0.150. Methanolic extract of Zingiber officinale (200µg/ml have SPF value about 1.48±0.094 and methanolic extract of Zingiber officinale (400µg/ml have SPF value about 1.99±0.033. Marketed sunscreen lotion having concentration 200µg/ml shows SPF value about 0.66±0.006. It shows that the aqueous and methanolic extract of Zingiber officinale may absorb the UV radiation and possess good sun protection activity against ultraviolet radiation. These results show that active components responsible for ultraviolet absorption may be isolated from Zingiber officinale and used in sunscreens preparations for better protection against sun rays.

  11. Radiotracer Methods for Targeted Imaging of the Epidermal Growth Factor Receptor

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Kyung Ho; Lee, Kyung Han [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2008-06-15

    While indirect targeting strategies using reporter-genes are taking center stage in current molecular imaging research, another vital strategy has long involved direct imaging of specific receptors using radiolabeled ligands. Recently, there is renewal of immense interest in this area with particular attention to the epidermal growth factor receptor (EGFR), a transmembrane glycoprotein critically involved in the regulation of many cellular functions and malignancies. Recently, two novel classes of EGFR-targeting anticancer drugs have entered clinical trials with great expectations. These are monoclonal antibodies such as cetuximab that target the extracellular domain, and small molecule tyrosine kinase inhibitors such as gefitinib (Iressa) and erlotinib (Tarceva) that target the catalytic domain of the receptor. However, early results have showed disappointing survival benefits, disclosing a major challenge for this therapeutic strategy; namely, the need to identify tumors that are most likely to respond to the agents. To address this important clinical issue, several noninvasive imaging techniques are under investigation including radiolabeled probes based on small molecule tyrosine kinase inhibitors, anti-EGFR antibodies, and EGF peptides. This review describes the current status, limitations, and future prospects in the development of radiotracer methods for EGFR imaging.

  12. Drop Axis Ratio Distributions in Stratiform and Convective Rain

    Science.gov (United States)

    Thurai, M.; Bringi, V. N.; Petersen, W. A.; Schultz, C.

    2010-01-01

    A fully calibrated low profile 2D video disdrometer (2DVD) has been recording many different rainfall events in Northern Alabama (USA) since June 2007. An earlier publication reported drop shapes and axis ratio distributions determined for some of the events. For one of the cases examined, a noticeable shift in the 3.5 - 3.75 mm drop axis ratio distribution was noted. In this paper, we extend the earlier work by separating the 2DVD measurements into stratiform and convective rain. The separation is made possible by using the minute-by-minute drop size distribution (DSD) measured by the 2DVD. The 1-minute DSDs are fitted to a gamma distribution, and using a simple indexing technique which involves two of the fitted parameters, periods of convective and stratiform rain are separated for a given event. The output of the DSD indexing technique is qualitatively confirmed by comparing with simultaneous time series observations from a co-located UHF profiler which continuously records height profiles of reflectivity, Doppler mean and spectral width, all of which enable the identification of bright-band periods and, furthermore, periods of moderate and deep convection. Excellent consistency is found between the output of the DSD-based separation method and the profiler observations. Next, we utilize the output of DSD index-based separation method to flag the periods of severe convection for a given event. Drop axis ratios during the flagged periods are derived and compared with those during stratiform rain periods. Five cases have been considered. Axis ratio distributions do not show appreciable differences between stratiform and convective periods for four of the cases. The fifth case (the same case as reported earlier) shows a shift in the 3.5 - 3.75 mm drop axis ratios during a prolonged period of convection. The contoured shapes for these drops determined from the 2DVD camera data indicate the possibility of non-axisymmetric oscillations, compared with the contoured

  13. Automated segmentation of the human hippocampus along its longitudinal axis.

    Science.gov (United States)

    Lerma-Usabiaga, Garikoitz; Iglesias, Juan Eugenio; Insausti, Ricardo; Greve, Douglas N; Paz-Alonso, Pedro M

    2016-09-01

    The human hippocampal formation is a crucial brain structure for memory and cognitive function that is closely related to other subcortical and cortical brain regions. Recent neuroimaging studies have revealed differences along the hippocampal longitudinal axis in terms of structure, connectivity, and function, stressing the importance of improving the reliability of the available segmentation methods that are typically used to divide the hippocampus into its anterior and posterior parts. However, current segmentation conventions present two main sources of variability related to manual operations intended to correct in-scanner head position across subjects and the selection of dividing planes along the longitudinal axis. Here, our aim was twofold: (1) to characterize inter- and intra-rater variability associated with these manual operations and compare manual (landmark based) and automatic (percentage based) hippocampal anterior-posterior segmentation procedures; and (2) to propose and test automated rotation methods based on approximating the hippocampal longitudinal axis to a straight line (estimated with principal component analysis, PCA) or a quadratic Bézier curve (fitted with numerical methods); as well as an automated anterior-posterior hippocampal segmentation procedure based on the percentage-based method. Our results reveal that automated rotation and segmentation procedures, used in combination or independently, minimize inconsistencies generated by the accumulation of manual operations while providing higher statistical power to detect well-known effects. A Matlab-based implementation of these procedures is made publicly available to the research community. Hum Brain Mapp 37:3353-3367, 2016. © 2016 Wiley Periodicals, Inc. PMID:27159325

  14. The comparison of cardiovascular risk scores using two methods of substituting missing risk factor data in patient medical records

    Directory of Open Access Journals (Sweden)

    Andrew Dalton

    2011-07-01

    Conclusions A simple method of substituting missing risk factor data can produce reliable estimates of CVD risk scores. Targeted screening for high CVD risk, using pre-existing electronic medical record data, does not require multiple imputation methods in risk estimation.

  15. Tuning the DARHT Axis-II linear induction accelerator focusing

    Energy Technology Data Exchange (ETDEWEB)

    Ekdahl, Carl A. [Los Alamos National Laboratory

    2012-04-24

    accelerator cell to replace a failed solenoid in March of 2012. We took advantage of this opportunity to improve the design of the focusing tune with better models of the remaining partially failed solenoids, better estimates of beam initial conditions, and better values for pulsed-power voltages. As with all previous tunes for Axis-II, this one incorporates measures to mitigate beam-breakup (BBU) instability, image displacement instability (IDI), corkscrew (sweep), and emittance growth. Section II covers the general approach to of design of focusing solenoid tunes for the DARHT Axis-2 LIA. Section III explains the specific requirements and simulations needed to design the tune for the injector, which includes the thermionic electron source, diode, and six induction cells. Section IV explains the requirements and simulations for tuning the main accelerator, which consists of 68 induction cells. Finally, Section V explores sensitivity of the tune to deviations of parameters from nominal, random variations, and uncertainties in values. Four appendices list solenoid settings for this new tune, discuss comparisons of different simulation codes, show halo formation in mismatched beams, and present a brief discussion of the beam envelope equation, which is the heart of the method used to design LIA solenoid tunes.

  16. Rotation axis demultiplexer enabling simultaneous computed tomography of multiple samples.

    Science.gov (United States)

    Trtik, Pavel; Geiger, Fabian; Hovind, Jan; Lang, Udo; Lehmann, Eberhard; Vontobel, Peter; Peetermans, Steven

    2016-01-01

    This paper describes a device that allows for simultaneous tomographic imaging of samples on three independent rotational axes. This rotation axis demultiplexer (POLYTOM) is equipped with anti-backlash gears and placed on a standard sample rotation stage thus allowing for the transformation of the input rotation axis onto two additional parallel vertical axes. Consequently, three times the number of samples can be investigated within a given time period, thereby reducing the acquisition time of multiple sample tomographic investigations by a factor of three. The results of our pilot experiments using neutron tomographic imaging are presented. We foresee that the device will be of particular use for tomographic imaging of elongated samples at low-flux (e.g. neutron) sources; however, its use for the more widespread types of imaging techniques (e.g. X-rays) is not ruled out. The highlights of this new device for the purpose of the (neutron) computed tomography are: •Anti-backlash transformation of the input rotation onto two additional rotational axes.•Reduction of the acquisition time of the multiple sample tomographic investigations by a factor of three.•Low-cost. PMID:27158597

  17. Bouncing back - trauma and the HPA-axis in healthy adults

    OpenAIRE

    Ellen Renée Klaassens

    2010-01-01

    Background Dysregulation of the hypothalamic–pituitary–adrenal (HPA)-axis is thought to underlie stress-related psychiatric disorders such as posttraumatic stress disorder (PTSD). Some studies have reported HPA-axis dysregulation in trauma-exposed (TE) adults in the absence of psychiatric morbidity. In this dissertation we set out to unravel part of the mechanism that underlies the complex relations between trauma exposure, stress regulation, and psychopathology. Method Mentally healthy TE su...

  18. 两轴光纤陀螺连续测斜仪姿态解算方法研究%Research of attitude algorithm method of the two-axis FOG continuous inclinometer

    Institute of Scientific and Technical Information of China (English)

    李晨曦; 史晓锋

    2016-01-01

    In view of the small diameter of fiber optic gyro inclinometer application demand ,an attitude algorithms of continuous survey system based on an improved attitude heading reference system was proposed .The algorithm fuses aerospace inertial navigation model and petroleum logging parameters ,including two optical fiber gyroscopes and three accelerometers to form inertial measurement unit (IM U ) . According to inertial navigation principle , an improved attitude heading reference system is extended to the wellbore survey field .Using the output data of IMU after the algorithm calculated ,the attitude angles of dynamic continuous logging is calculated by the quaternion method .The algorithm decreases one optical fiber gyroscope than general IMU ,thus reduces the volume ,weight and cost .The simulation results show that the algorithm meet the demand of oil well logging technology .%针对小直径光纤陀螺连续测斜仪的应用需求,提出了一种基于改进航向姿态参考系统的连续测斜姿态解算方法。该算法融合航空惯性导航模型和石油测井工程参数,采用2个单自由度光纤陀螺和3个加速度计组成惯性测量单元(IMU),由惯性单元输出数据经该算法计算出动态连续测井的实时姿态角。通过仿真研究表明:该算法解算出的实时姿态角的误差均在1°以内,符合石油测井的技术需求。该算法的优势在于,在实现连续测量功能的同时相对普通惯性测量单元减少了一个光纤陀螺,从而减小了测斜仪的体积、重量,降低了成本。

  19. Multi-axis analog adaptive feedforward cancellation of cryocooler vibration

    Science.gov (United States)

    Collins, Simon Andrew

    1994-01-01

    The vibration produced by Stirling cryocoolers is incompatible with spacecraft-borne precision-pointing imaging instruments. Thermal considerations prevent the addition of sufficient mechanical isolation to eliminate the effects of this vibration. The objective of this research is the design, analysis, and experimental verification of a multi-axis vibration cancellation system for the expander of a split Stirling cryocooler. Cancellation of the periodic cryocooler vibration is achieved with a set of load cells, a custom three-axis electrodynamic actuator, and a narrowband adaptive feedforward controller. In order to size the actuator, a simple model of the cryocooler's vibration is combined with a first-order analysis of a four-magnet two-return-plate forcing element. While the resulting actuator has sufficient force capability, it exhibits significant nonlinearity. A nonlinear actuator model is developed that accounts for in-plane flexure restraint due to both large-amplitude static deflections and large-amplitude vibrations. Numerical solutions of the nonlinear model accurately reflect jump phenomena and higher harmonics observed in the actuator's response. The adaptive feedforward controller employs the filtered-x least-mean-square (FXLMS) algorithm to update an adaptive filter. Rather than implementing this filter with a digital signal processor (DSP), for which there is little flight heritage, a continuous-time analog realization of the FXLMS filter is selected. Theoretically, the FXLMS filter may be represented by an equivalent linear transfer function. However a comprehensive treatment of factors associated with the actual implementation reveals the limitations of the transfer function representation. Factors such as harmonic distortion of the reference signal and imperfect quadrature are shown to result in frequency-shifted terms in the filter's output. The presence of these output components is confirmed experimentally, and their effect on performance is

  20. Turbulence in vertical axis wind turbine canopies

    OpenAIRE

    Kinzel, Matthias; Araya, Daniel B.; Dabiri, John O.

    2015-01-01

    Experimental results from three different full scale arrays of vertical-axis wind turbines (VAWTs) under natural wind conditions are presented. The wind velocities throughout the turbine arrays are measured using a portable meteorological tower with seven, vertically staggered, three-component ultrasonic anemometers. The power output of each turbine is recorded simultaneously. The comparison between the horizontal and vertical energy transport for the different turbine array sizes shows the i...

  1. Local Pancake Defeats Axis of Evil

    OpenAIRE

    Vale, Chris

    2005-01-01

    Among the biggest surprises revealed by COBE and confirmed by WMAP measurements of the temperature anisotropy of the CMB are the anomalous features in the 2-point angular correlation function on very large angular scales. In particular, the $\\ell = 2$ quadrupole and $\\ell = 3$ octopole terms are surprisingly planar and aligned with one another, which is highly unlikely for a statistically isotropic Gaussian random field, and the axis of the combined low-$\\ell$ signal is perpendicular to eclip...

  2. Impedances and power losses for an off-axis beam

    CERN Document Server

    Kurennoy, S S

    1996-01-01

    A method for calculating coupling impedances and power losses for off-axis beams is developed. It is applied to calculate impedances of small localized discontinuities like holes and slots, as well as the impedance due to a finite resistivity of chamber walls, in homogeneous chambers with an arbitrary shape of the chamber cross section. The approach requires to solve a two-dimensional electrostatic problem, which can be easily done numerically in the general case, while for some particular cases analytical solutions are obtained.

  3. On the off-axis tensile test for unidirectional composites

    Science.gov (United States)

    Nemeth, M. P.; Herakovich, C. T.; Post, D.

    1982-01-01

    The off axis tensile test was examined experimentally to obtain actual displacement fields over the surface of graphite polyimide coupon specimens. The experimental results were compared with approximate analytical solutions and generated finite element results. An optical method of high sensitivity moire interferometry was used to determine the actual displacements to high precision. The approximate analytical solution and the finite element results compare very favorably with the measured centerline displacements in the test section, and the finite element displacement fields provide excellent agreement with the moire displacements throughout the specimen. A 15 degree fiber orientation and coupon aspect ratios of 5 and 15 are presented.

  4. Using a knowledge elicitation method to specify the business model of a human factors organization

    NARCIS (Netherlands)

    Schraagen, Jan Maarten; Ven, van de Josine; Hoffman, Robert R.; Moon, Brian M.

    2009-01-01

    Concept Mapping was used to structure knowledge elicitation interviews with a group of human factors specialists whose goal was to describe the business model of their Department. This novel use of cognitive task analysis to describe the business model of a human factors organization resulted in a n

  5. Identifying the most critical project complexity factors using Delphi method: the Iranian construction industry

    Directory of Open Access Journals (Sweden)

    Mohammad Mehdi Mozaffari

    2012-09-01

    Full Text Available Complexity is one of the most important issues influencing success of any construction project and there are literally different studies devoted to detect important factors increasing complexity of projects. During the past few years, there have been growing interests in developing mass construction projects in Iran. The proposed study of this paper uses Delphi technique to find out about important factors as barriers of construction projects in Iran. The results show that among 47 project complexity factors, 19 factors are more important than others are. The study groups different factors into seven categories including environmental, organizational, objectives, tasks, stakeholders, technological, information systems and determines the relative importance of each. In each group, many other sub group activities are determined and they are carefully investigated. The study provides some detailed suggestions on each category to reduce the complexity of construction project.

  6. Improving cluster-based methods for investigating potential for insect pest species establishment: region-specific risk factors

    OpenAIRE

    Watts, Michael J.; Worner, Susan P.

    2011-01-01

    Existing cluster-based methods for investigating insect species assemblages or profiles of a region to indicate the risk of new insect pest invasion have a major limitation in that they assign the same species risk factors to each region in a cluster. Clearly regions assigned to the same cluster have different degrees of similarity with respect to their species profile or assemblage. This study addresses this concern by applying weighting factors to the cluster elements used to calculate regi...

  7. Load Concentration Factor Based Analytical Method for Optimal Placement of Multiple Distribution Generators for Loss Minimization and Voltage Profile Improvement

    OpenAIRE

    Mohsin Shahzad; Ishtiaq Ahmad; Wolfgang Gawlik; Peter Palensky

    2016-01-01

    This paper presents novel separate methods for finding optimal locations, sizes of multiple distributed generators (DGs) simultaneously and operational power factor in order to minimize power loss and improve the voltage profile in the distribution system. A load concentration factor (LCF) is introduced to select the optimal location(s) for DG placement. Exact loss formula based analytical expressions are derived for calculating the optimal sizes of any number of DGs simultaneously. Since nei...

  8. Analysis Method Research on the Importance of the Factors Influencing the Flow Safety of Heated Crude Pipelines

    OpenAIRE

    Zhigang Duan; Qiao Xiao; Guoxi He; Yongtu Liang; Zhe Tan

    2014-01-01

    Analyzing the importance of the factors which influence the flow safety of the heated oil pipeline is an important part of the whole assessment process, which is of great significance on the results analysis, phenomenon explanation, and risk control after the assessment. Focusing on the problems in the influencing factors’ importance analysis on crude oil pipeline flow assurance assessment, a new method to analyze the importance of the influencing factors is proposed which considers the facto...

  9. Design and implementation of a multi-axis precision movement machine based on MAS theory

    Institute of Scientific and Technical Information of China (English)

    Li MA; Linlin CI; Genyan GE

    2009-01-01

    A model construction of a multi-agent system (MAS) and the basic function of the agent are described.The precision control method using the multi-CPU of a programmable logic controller (PLC) is introduced,and a distributed method using multiple CPUs to control different motion machines is given.The test results indicate that in industrial control fields,the combination of using the credible PLC to control the motion machine and multi-CPU task distributing methods can solve multi-axis machine linkage and implication,providing a more credible method for multi-axis motion units.

  10. Seizure-induced disinhibition of the HPA axis increases seizure susceptibility.

    Science.gov (United States)

    O'Toole, Kate K; Hooper, Andrew; Wakefield, Seth; Maguire, Jamie

    2014-01-01

    Stress is the most commonly reported precipitating factor for seizures. The proconvulsant actions of stress hormones are thought to mediate the effects of stress on seizure susceptibility. Interestingly, epileptic patients have increased basal levels of stress hormones, including corticotropin-releasing hormone (CRH) and corticosterone, which are further increased following seizures. Given the proconvulsant actions of stress hormones, we proposed that seizure-induced activation of the hypothalamic-pituitary-adrenal (HPA) axis may contribute to future seizure susceptibility. Consistent with this hypothesis, our data demonstrate that pharmacological induction of seizures in mice with kainic acid or pilocarpine increases circulating levels of the stress hormone, corticosterone, and exogenous corticosterone administration is sufficient to increase seizure susceptibility. However, the mechanism(s) whereby seizures activate the HPA axis remain unknown. Here we demonstrate that seizure-induced activation of the HPA axis involves compromised GABAergic control of CRH neurons, which govern HPA axis function. Following seizure activity, there is a collapse of the chloride gradient due to changes in NKCC1 and KCC2 expression, resulting in reduced amplitude of sIPSPs and even depolarizing effects of GABA on CRH neurons. Seizure-induced activation of the HPA axis results in future seizure susceptibility which can be blocked by treatment with an NKCC1 inhibitor, bumetanide, or blocking the CRH signaling with Antalarmin. These data suggest that compromised GABAergic control of CRH neurons following an initial seizure event may cause hyperexcitability of the HPA axis and increase future seizure susceptibility.

  11. Determination of High-Frequency d- and q-axis Inductances for Surface-Mounted Permanent-Magnet Synchronous Machines

    DEFF Research Database (Denmark)

    Lu, Kaiyuan; Vetuschi, M.; Rasmussen, Peter Omand;

    2010-01-01

    This paper presents a reliable method for the experimental determination of high-frequency d- and q -axis inductances for surface-mounted permanent-magnet synchronous machines (SMPMSMs). Knowledge of the high-frequency d- and q-axis inductances plays an important role in the efficient design of...

  12. Cytogenetic method of determining effect of threshold values of anthropogenic factors on the plant and animal genome

    International Nuclear Information System (INIS)

    The use of nucleolar characteristics to access the action of physical and chemical factors on living objects is a promising trend in the creation of new and highly sensitive biological tests. The advantages of this process are that the effect of the threshold values of the anthropogenic factors is recorded as a change in functional activity of the cell genome and not as the restructuring of the karyotype. The aim of this research was to test a cytogenetic method of determining the modifying action of various factors on the plant and animal genome, based on analysis of quantitative characteristics of the nucleoli and to extend its use to different groups of organisms

  13. Milk consumption and the prepubertal somatotropic axis

    Directory of Open Access Journals (Sweden)

    Nakamoto Erika K

    2007-09-01

    Full Text Available Abstract Background Nutrients, hormones and growth factors in dairy foods may stimulate growth hormone (GH, insulin-like growth factor I (IGF-I, and raise the ratio of IGF-I to its binding protein, IGFBP-3. We conducted pilot studies in Mongolia and Massachusetts to test the extent to which milk intake raised somatotropic hormone concentrations in prepubertal children. Methods In Ulaanbaatar, we compared plasma levels before and after introducing 710 ml daily whole milk for a month among 46 10–11 year old schoolchildren. In a randomized cross-over study in Boston, we compared plasma hormone levels of 28 6–8 year old girls after one week of drinking 710 ml lowfat (2% milk with their hormone levels after one week of consuming a macronutrient substitute for milk. Results After a month of drinking whole milk, Mongolian children had higher mean plasma levels of IGF-I (p th percentile of GH levels (p = 0.005. After a week of drinking lowfat milk, Boston girls had small and non-significant increases in IGF-1, IGF-1/IGFBP-3 and GH. Conclusion Milk drinking may cause increases in somatotropic hormone levels of prepubertal girls and boys. The finding that milk intake may raise GH levels is novel, and suggests that nutrients or bioactive factors in milk may stimulate endogenous GH production.

  14. Related Axis: The Extension to XPath Towards Effective XML Search

    Institute of Scientific and Technical Information of China (English)

    Jun-Feng Zhou; Tok Wang Ling; Zhi-Feng Bao; Xiao-Feng Meng

    2012-01-01

    We investigate the limitations of existing XML search methods and propose a new semantics,related relationship,to effectively capture meaningful relationships of data elements from XML data in the absence of structural constraints.Then we make an extension to XPath by introducing a new axis,related axis,to specify the related relationship between query nodes so as to enhance the flexibility of XPath.We propose to reduce the cost of computing the related relationship by a new schema summary that summarizes the related relationship from the original schema without any loss.Based on this schema summary,we introduce two indices to improve the performance of query processing.Our algorithm shows that the evaluation of most queries can be equivalently transformed into just a few selection and value join operations,thus avoids the costly structural join operations.The experimental results show that our method is effective and efficient in terms of comparing the effectiveness of the related relationship with existing keyword search semantics and comparing the efficiency of our evaluation methods with existing query engines.

  15. Rapid fabrication of miniature lens arrays by four-axis single point diamond machining.

    Science.gov (United States)

    McCall, Brian; Tkaczyk, Tomasz S

    2013-02-11

    A novel method for fabricating lens arrays and other non-rotationally symmetric free-form optics is presented. This is a diamond machining technique using 4 controlled axes of motion - X, Y, Z, and C. As in 3-axis diamond micro-milling, a diamond ball endmill is mounted to the work spindle of a 4-axis ultra-precision computer numerical control (CNC) machine. Unlike 3-axis micro-milling, the C-axis is used to hold the cutting edge of the tool in contact with the lens surface for the entire cut. This allows the feed rates to be doubled compared to the current state of the art of micro-milling while producing an optically smooth surface with very low surface form error and exceptionally low radius error.

  16. Cross-axis adaptation of torsional components in the yaw-axis vestibulo-ocular reflex

    Science.gov (United States)

    Trillenberg, P.; Shelhamer, M.; Roberts, D. C.; Zee, D. S.

    2003-01-01

    The three pairs of semicircular canals within the labyrinth are not perfectly aligned with the pulling directions of the six extraocular muscles. Therefore, for a given head movement, the vestibulo-ocular reflex (VOR) depends upon central neural mechanisms that couple the canals to the muscles with the appropriate functional gains in order to generate a response that rotates the eye the correct amount and around the correct axis. A consequence of these neural connections is a cross-axis adaptive capability, which can be stimulated experimentally when head rotation is around one axis and visual motion about another. From this visual-vestibular conflict the brain infers that the slow-phase eye movement is rotating around the wrong axis. We explored the capability of human cross-axis adaptation, using a short-term training paradigm, to determine if torsional eye movements could be elicited by yaw (horizontal) head rotation (where torsion is normally inappropriate). We applied yaw sinusoidal head rotation (+/-10 degrees, 0.33 Hz) and measured eye movement responses in the dark, and before and after adaptation. The adaptation paradigm lasted 45-60 min, and consisted of the identical head motion, coupled with a moving visual scene that required one of several types of eye movements: (1) torsion alone (-Roll); (2) horizontal/torsional, head right/CW torsion (Yaw-Roll); (3) horizontal/torsional, head right/CCW torsion (Yaw+Roll); (4) horizontal, vertical, torsional combined (Yaw+Pitch-Roll); and (5) horizontal and vertical together (Yaw+Pitch). The largest and most significant changes in torsional amplitude occurred in the Yaw-Roll and Yaw+Roll conditions. We conclude that short-term, cross-axis adaptation of torsion is possible but constrained by the complexity of the adaptation task: smaller torsional components are produced if more than one cross-coupling component is required. In contrast, vertical cross-axis components can be easily trained to occur with yaw head

  17. Application of the incomplete Cholesky factorization preconditioned Krylov subspace method to the vector finite element method for 3-D electromagnetic scattering problems

    Science.gov (United States)

    Li, Liang; Huang, Ting-Zhu; Jing, Yan-Fei; Zhang, Yong

    2010-02-01

    The incomplete Cholesky (IC) factorization preconditioning technique is applied to the Krylov subspace methods for solving large systems of linear equations resulted from the use of edge-based finite element method (FEM). The construction of the preconditioner is based on the fact that the coefficient matrix is represented in an upper triangular compressed sparse row (CSR) form. An efficient implementation of the IC factorization is described in detail for complex symmetric matrices. With some ordering schemes our IC algorithm can greatly reduce the memory requirement as well as the iteration numbers. Numerical tests on harmonic analysis for plane wave scattering from a metallic plate and a metallic sphere coated by a lossy dielectric layer show the efficiency of this method.

  18. Factorization method for difference equations of hypergeometric type on nonuniform lattices

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez-Nodarse, R. [Departamento de Analisis Matematico, Universidad de Sevilla, Sevilla (Spain); Instituto Carlos I de Fisica Teorica y Computacional, Universidad de Granada, Granada (Spain); Costas-Santos, R.S. [Departamento de Analisis Matematico, Universidad de Sevilla, Sevilla (Spain)

    2001-07-13

    We study the factorization of the hypergeometric-type difference equation of Nikiforov and Uvarov on nonuniform lattices. An explicit form of the raising and lowering operators is derived and some relevant examples are given. (author)

  19. Mode I Critical Stress Intensity Factor of Beech Wood (Fagus Sylvatica in a TL Configuration: A Comparison of Different Methods

    Directory of Open Access Journals (Sweden)

    Miran Merhar, Dominika Gornik Bučar, Bojan Buča

    2013-09-01

    Full Text Available The paper presents a comparison between various methods of mode I critical stress intensity factor KIC calculations of beech wood in the TL configuration. The first method is the stress intensity factor extrapolation to the distance of 0 mm from the crack tip; the second method is the use of the J integral; and the third method is based on the differences in deformation energies from which the strain energy release rate per unit of crack propagation length was obtained. The fourth method is the calculation of material deformation around the crack or the displacement of the triangle element node; and the fifth method uses a generally known equation for the CT specimen for plane-strain conditions in isotropic material. Using the finite element method, it was found that the J integral was least sensitive to the size and shape of the elements. It was used to calculate the critical stress intensity factor KIC for beech wood in a TL configuration. The average value is 0.56 MPa√m with a standard deviation of 0.047 MPa√m.

  20. Exploration of the factors that influence nutritional recovery following critical illness : a mixed methods study

    OpenAIRE

    Merriweather, Judith Lorna

    2014-01-01

    Survivors of critical illness suffer from a range of problems affecting physical, psychological and social well-being (Needham et al 2011). Weakness, fatigue and malnutrition are highly prevalent during the months following a critical illness. Few studies have systematically and comprehensively explored the factors that influence nutritional recovery or ways to overcome them. The aim of this study was to provide a comprehensive understanding of the factors influencing nutrition...