931 resultados para Mean-value deviance (MVD)


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An effective control of the ion current distribution over large-area (up to 103 cm2) substrates with the magnetic fields of a complex structure by using two additional magnetic coils installed under the substrate exposed to vacuum arc plasmas is demonstrated. When the magnetic field generated by the additional coils is aligned with the direction of the magnetic field generated by the guiding and focusing coils of the vacuum arc source, a narrow ion density distribution with the maximum current density 117 A m-2 is achieved. When one of the additional coils is set to generate the magnetic field of the opposite direction, an area almost uniform over the substrate of 103 cm2 ion current distribution with the mean value of 45 A m-2 is achieved. Our findings suggest that the system with the vacuum arc source and two additional magnetic coils can be effectively used for the effective, high throughput, and highly controllable plasma processing.

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Background: In recent years, there have been investigations concerning upper-limbs kinematics by various devices. The latest generation of smartphones often includes inertial sensors with subunits which can detect inertial kinematics. The use of smartphones is presented as a convenient and portable analysis method for studying kinematics in terms of angular mobility and linear acceleration Objective: The aim of this study was to study humerus kinematics through six physical properties that correspond to angular mobility and acceleration in the three axes of space, obtained by a smartphone. Methods: This cross-sectional study recruited healthy young adult subjects. Descriptive and anthropometric independent variables related to age, gender, weight, size, and BMI were included. Six physical properties were included corresponding to two dependent variables for each of three special axes: mobility angle (degrees) and lineal acceleration (meters/seconds2), which were obtained thought the inertial measurement sensor embedded in the iPhone4 smartphone equipped with three two elements for the detection of kinematic variables: a gyroscope and an accelerometer. Apple uses an LIS302DL accelerometer in the iPhone4. The application used to obtain kinematic data was xSensor Pro, Crossbow Technology, Inc., available at the Apple AppStore. The iPhone4 has storage capacity of 20MB. The data-sampling rate was set to 32 Hz, and the data for each analytical task was transmitted as email for analysis and postprocessing The iPhone4 was placed in the right half of the body of each subject located in the middle third of the humerus slightly posterior snugly secured by a neoprene fixation belt. Tasks were explained concisely and clearly. The beginning and the end were decided by a verbal order by the researcher. Participants were placed standing, starting from neutral position, performing the following analytical tasks: 180º right shoulder abduction (eight repetitions) and, after a break of about 3 minutes, 180º right shoulder flexion (eight repetitions). Both tasks were performed with the elbow extended, wrist in neutral position and the palmar area of the hand toward the midline at the beginning and end of the movement. Results: A total of 11 subjects (8 men, 3 woman) were measured, whose mean of age was 24.7 years (SD = 4.22 years) and their average BMI was 22.64 Kg/m2 (SD = 2.29 Kg/m2). The mean of angular mobility collected by the smartphone was bigger in pitch axis for flexion (= 157.28°, SD= 12.35°) and abduction (= 151.71°, SD= 9.70°). With regard to acceleration, the highest peak mean value was shown in the Y motion axis during flexion (= 19.5°/s2, SD = 0.8°/s2) and abduction (= 19.4°/s2, SD = 0.8°/s2). Also, descriptive graphics of analytical tasks performed were obtained. Conclusions: This study shows how humerus contributes to upper-limb motion and it identified movement patterns. Therefore, it supports smartphone as a useful device to analyze upper-limb kinematics. Thanks to this study it´s possible to develop a simple application that facilitates the evaluation of the patient.

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his paper identifies some scaling relationships between solar activity and geomagnetic activity. We examine the scaling properties of hourly data for two geomagnetic indices (ap and AE), two solar indices (solar X-rays Xl and solar flux F10.7), and two inner heliospheric indices (ion density Ni and flow speed Vs) over the period 1995–2001 by the universal multifractal approach and the traditional multifractal analysis. We found that the universal multifractal model (UMM) provides a good fit to the empirical K(q) and τ(q) curves of these time series. The estimated values of the Lévy index α in the UMM indicate that multifractality exists in the time series for ap, AE, Xl, and Ni, while those for F10.7 and Vs are monofractal. The estimated values of the nonconservation parameter H of this model confirm that these time series are conservative which indicate that the mean value of the process is constant for varying resolution. Additionally, the multifractal K(q) and τ(q) curves, and the estimated values of the sparseness parameter C1 of the UMM indicate that there are three pairs of indices displaying similar scaling properties, namely ap and Xl, AE and Ni, and F10.7 and Vs. The similarity in the scaling properties of pairs (ap,Xl) and (AE,Ni) suggests that ap and Xl, AE and Ni are better correlated—in terms of scaling—than previous thought, respectively. But our results still cannot be used to advance forecasting of ap and AE by Xl and Ni, respectively, due to some reasons

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Purpose This study evaluated the impact of patient set-up errors on the probability of pulmonary and cardiac complications in the irradiation of left-sided breast cancer. Methods and Materials Using the CMS XiO Version 4.6 (CMS Inc., St Louis, MO) radiotherapy planning system's NTCP algorithm and the Lyman -Kutcher-Burman (LKB) model, we calculated the DVH indices for the ipsilateral lung and heart and the resultant normal tissue complication probabilities (NTCP) for radiation-induced pneumonitis and excess cardiac mortality in 12 left-sided breast cancer patients. Results Isocenter shifts in the posterior direction had the greatest effect on the lung V20, heart V25, mean and maximum doses to the lung and the heart. Dose volume histograms (DVH) results show that the ipsilateral lung V20 tolerance was exceeded in 58% of the patients after 1cm posterior shifts. Similarly, the heart V25 tolerance was exceeded after 1cm antero-posterior and left-right isocentric shifts in 70% of the patients. The baseline NTCPs for radiation-induced pneumonitis ranged from 0.73% - 3.4% with a mean value of 1.7%. The maximum reported NTCP for radiation-induced pneumonitis was 5.8% (mean 2.6%) after 1cm posterior isocentric shift. The NTCP for excess cardiac mortality were 0 % in 100% of the patients (n=12) before and after setup error simulations. Conclusions Set-up errors in left sided breast cancer patients have a statistically significant impact on the Lung NTCPs and DVH indices. However, with a central lung distance of 3cm or less (CLD <3cm), and a maximum heart distance of 1.5cm or less (MHD<1.5cm), the treatment plans could tolerate set-up errors of up to 1cm without any change in the NTCP to the heart.

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Winter cereal cropping is marginal in south-west Queensland because of low and variable rainfall and declining soil fertility. Increasing the soil water storage and the efficiency of water and nitrogen (N) use is essential for sustainable cereal production. The effect of zero tillage and N fertiliser application on these factors was evaluated in wheat and barley from 1996 to 2001 on a grey Vertosol. Annual rainfall was above average in 1996, 1997, 1998 and 1999 and below average in 2000 and 2001. Due to drought, no crop was grown in the 2000 winter cropping season. Zero tillage improved fallow soil water storage by a mean value of 20 mm over 4 years, compared with conventional tillage. However, mean grain yield and gross margin of wheat were similar under conventional and zero tillage. Wheat grain yield and/or grain protein increased with N fertiliser application in all years, resulting in an increase in mean gross margin over 5 years from $86/ha, with no N fertiliser applied, to $250/ha, with N applied to target ≥13% grain protein. A similar increase in gross margin occurred in barley where N fertiliser was applied to target malting grade. The highest N fertiliser application rate in wheat resulted in a residual benefit to soil N supply for the following crop. This study has shown that profitable responses to N fertiliser addition in wheat and barley can be obtained on long-term cultivated Vertosols in south-west Queensland when soil water reserves at sowing are at least 60% of plant available water capacity, or rainfall during the growing season is above average. An integrative benchmark for improved N fertiliser management appears to be the gross margin/water use of ~$1/ha.mm. Greater fallow soil water storage or crop water use efficiency under zero tillage has the potential to improve winter cereal production in drier growing seasons than experienced during the period of this study.

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The aim of the present study was to assess dental health and its determinants among 15-year-olds in Tehran, Iran and to evaluate the impact of a school-based educational intervention on their oral cleanliness and gingival health. The total sample comprised 506 students. Data collection was performed through a clinical dental examination and a self-administered structured questionnaire. This questionnaire covered the student s background information, socio-economic status, self-perceived dental health, tooth-brushing, and smoking. The clinical dental examination covered caries experience, gingival status, dental plaque status, and orthodontic treatment needs. Participation was voluntary, and all students responded to the questionnaire. Only three students refused the clinical dental examination. The intervention was based on exposing students to dental health education through a leaflet and a videotape designed for the present study. The outcome examinations took place 12 weeks after the baseline among the three groups of the intervention trial (leaflet, videotape, and control). High participation rates at the baseline and scanty drop-outs (7%) in the intervention speak for reliability of the results. Mean value of the DMFT (D=decayed, M=missing, and F=filled teeth) index of the 15-year-olds was 2.1, which comprised DT=0.9, MT=0.2, and FT=1.0 with no gender differences. Dental plaque existed on at least one index tooth of all students, and healthy periodontium (Community Periodontal Index=0) was found in less than 10% of students. Need for caries treatment existed in 40% of students, for scaling in 24%, for oral hygiene instructions in all, and for orthodontic treatment in 26%. Students with the highest level of parents education had fewer dental caries (36% vs. 48%) and less dental plaque (77% vs. 88%). Of all students, 78% assessed their dental health as good or better. Even more of those with their DMFT=0 (73% vs. 27%) and DT=0 (68% vs. 32%) assessed their dental health as good or better. Smokers comprised 5% of the boys and 2% of the girls. Smoking was common among students of less-educated parents (6% vs. 3%). Of all students, 26% reported twice-daily tooth-brushing; girls (38% vs. 15%) and those of higher socio-economic background (33% vs. 17%) did so more frequently. The best predictors for a good level of oral cleanliness were female gender or twice-daily tooth-brushing. The present study demonstrated that a school-based educational intervention can be effective in the short term in improving the oral cleanliness and gingival health of adolescents. At least 50% reduction in numbers of teeth with dental plaque compared to baseline was achieved by 58% of the students in the leaflet group, by 37% in the videotape group, and by 10% of the controls. Corresponding figures for gingival bleeding were 72%, 64%, and 30%. For improving the oral cleanliness and gingival health of adolescents in countries such as Iran with a developing oral health system, school-based educational intervention should be established with focus on oral self-care and oral health education messages. Emphasizing the immediate gains from good oral hygiene, such as fresh breath, clean teeth, and attractive appearance should be key aspects for motivating these adolescents to learn and maintain good dental health, whilst in planning school-based dental health intervention, special attention should be given to boys and those with lower socio-economic status. Author s address: Reza Yazdani, Department of Oral Public Health, Institute of Dentistry, University of Helsinki, P.O. Box 41, FI-00014 Helsinki, Finland. E-mail: reza.yazdani@helsinki.fi

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Assessment of genetic diversity is an essential component in germplasm characterisation and utilisation. In this study the genetic diversity of mango was determined among 254 Mangifera indica L. accessions and related Mangifera species originating from 12 diverse geographic areas using eleven known simple sequence repeat (SSR) markers from mango. A total of 133 alleles were detected, ranging from eight (LMMA12) to 16 (MIAC-5) alleles per locus with a mean value of 12.36 and an average polymorphism information content (PLC) of 0.72. The mean number of alleles (8.45) was highest in the South East Asian accessions (Indonesia/Malesia) and lowest in the accessions from the Philippines (2.55). Diversity analysis divided the accessions into four major nodes broadly representing their geographical origins. The genetic diversity of 'Kensington Pride' was confirmed as being very low and no parents for this cultivar were identified. No association could be established between SSR markers analysed and embryony. Ten synonymous accessions were identified with matching genetic identity with at least one other accession at all SSR loci examined. Twenty-two unique genotypes were identified for 50 trees previously assigned different accession names. The remaining accessions were genetically distinct from each other. This increased understanding of genetic diversity in the Australian National Mango Genebank will assist breeders to better select parents with the potential to contribute desired genes to the progeny and thus more rapidly deliver improved cultivars to industry to meet consumer demand. Crown Copyright (C) 2012 Published by Elsevier B.V. All rights reserved.

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1. The rat brain type IIA Na+ channel alpha-subunit was stably expressed in Chinese hamster ovary (CHO) cells. Current through the expressed Na+ channels was studied using the whole-cell configuration of the patch clamp technique. The transient Na+ current was sensitive to TTX and showed a bell-shaped peak current vs. membrane potential relation. 2. Na+ current inactivation was better described by the sum of two exponentials in the potential range -30 to +40 mV, with. a dominating fast component and a small slower component. 3. The steady-state inactivation, h(infinity), was related to potential by a Boltzmann distribution, underlying thr ee states of the inactivation gate. 4. Recovery of the channels from inactivation at different potentials in the range -70 to -120 mV were characterized by al? initial delay which decreased with hyperpolarization. The time course was well fitted by the sum of two exponentials. In this case the slower exponential was the major component, and both time constants decreased with hyperpolarization. 5. For a working description of the Na+ channel inactivation in this preparation, with a minimal deviation from the Hodgkin-Huxley model, a three-state scheme of the form O reversible arrow I-1 reversible arrow I-2 was proposed, replacing the original two-state scheme of the Hodgkin-Huxley model, and the rate constants are reported. 6. The instantaneous current-voltage relationship showed marked deviation from linearity and was satisfactorily fitted by the constant-field equation. 7. The time course of activation was described by an m(x) model. However, the best-fitted value of x varied with the membrane potential and had a mean value of 2. 8. Effective gating charge was determined to be 4.7e from the slope of the activation plot, plotted on a logarithmic scale. 9. The rate constants of activation, alpha(m) and beta(m), were determined. Their functional dependence on the membrane potential was investigated.

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The standard free energy of formation of titanium boride (TiB2) Was measured by the Electro Motive Force (EMF) method (by using yttria doped thoria (YDT) as the solid electrolyte). Two galvanic cells viz. Cell (I): Pt, TiB2 (s), TiO2 (s), B (s) vertical bar YDT vertical bar NiO (s), Ni (s), Pt and cell (II): Pt, TiB2 (s), TiO2 (s), B (s) vertical bar YDT vertical bar FeO (s). Fe (s), Pt were constructed in order to determine the Delta(f)G degrees, of TiB2. Enthalpy increments on TiB2 were measured by using inverse drop calorimetry over the temperature range 583-1769 K. The heat capacity, entropy and the free energy function have been derived from these experimental data in the temperature range 298-1800 K. The mean value of the standard enthalpy of formation of TiB2 (Delta H-f(298)degrees (TiB2)) was obtained by combining these Delta(f)G degrees, values and the free energy functions of TiB2 derived from the drop calorimetry data. The mean values of Delta H-f(298)degrees (TiB2) derived from the Delta(f)G degrees, data obtained from cell I and II were -322 +/- 1.2 kJ mol(-1) and -323.3 +/- 2.1 kJ mol(-1), respectively. These values were found to be in very good agreement with the assessed data. (C) 2009 Elsevier B.V. All rights reserved.

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STOAT has been extensively used for the dynamic simulation of an activated sludge based wastewater treatment plant in the Titagarh Sewage Treatment Plant, near Kolkata, India. Some alternative schemes were suggested. Different schemes were compared for the removal of Total Suspended Solids (TSS), b-COD, ammonia, nitrates etc. A combination of IAWQ#1 module with the Takacs module gave best results for the existing scenarios of the Titagarh Sewage Treatment Plant. The modified Bardenpho process was found most effective for reducing the mean b-COD level to as low as 31.4 mg/l, while the mean TSS level was as high as 100.98 mg/l as compared to the mean levels of TSS (92 62 mg/l) and b-COD (92.0 mg/l) in the existing plant. Scheme 2 gave a better scenario for the mean TSS level bringing it down to a mean value of 0.4 mg/l, but a higher mean value for the b-COD level at 54.89 mg/l. The Scheme Final could reduce the mean TSS level to 2.9 mg/l and the mean b-COD level to as low as 38.8 mg/l. The Final Scheme looks to be a technically viable scheme with respect to the overall effluent quality for the plant. (C) 2009 Elsevier B.V. All rights reserved.

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The current approach for protecting the receiving water environment from urban stormwater pollution is the adoption of structural measures commonly referred to as Water Sensitive Urban Design (WSUD). The treatment efficiency of WSUD measures closely depends on the design of the specific treatment units. As stormwater quality is influenced by rainfall characteristics, the selection of appropriate rainfall events for treatment design is essential to ensure the effectiveness of WSUD systems. Based on extensive field investigations in four urban residential catchments based at Gold Coast, Australia, and computer modelling, this paper details a technically robust approach for the selection of rainfall events for stormwater treatment design using a three-component model. The modelling results confirmed that high intensity-short duration events produce 58.0% of TS load while they only generated 29.1% of total runoff volume. Additionally, rainfall events smaller than 6-month average recurrence interval (ARI) generates a greater cumulative runoff volume (68.4% of the total annual runoff volume) and TS load (68.6% of the TS load exported) than the rainfall events larger than 6-month ARI. The results suggest that for the study catchments, stormwater treatment design could be based on the rainfall which had a mean value of 31 mm/h average intensity and 0.4 h duration. These outcomes also confirmed that selecting smaller ARI rainfall events with high intensity-short duration as the threshold for treatment system design is the most feasible approach since these events cumulatively generate a major portion of the annual pollutant load compared to the other types of events, despite producing a relatively smaller runoff volume. This implies that designs based on small and more frequent rainfall events rather than larger rainfall events would be appropriate in the context of efficiency in treatment performance, cost-effectiveness and possible savings in land area needed.

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A method is presented to model server unreliability in closed queuing networks. Breakdowns and repairs of servers, assumed to be time-dependent, are modeled using virtual customers and virtual servers in the system. The problem is thus converted into a closed queue with all reliable servers and preemptive resume priority centers. Several recent preemptive priority approximations and an approximation of the one proposed are used in the analysis. This method has approximately the same computational requirements as that of mean-value analysis for a network of identical dimensions and is therefore very efficient

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In this paper we present a cache coherence protocol for multistage interconnection network (MIN)-based multiprocessors with two distinct private caches: private-blocks caches (PCache) containing blocks private to a process and shared-blocks caches (SCache) containing data accessible by all processes. The architecture is extended by a coherence control bus connecting all shared-block cache controllers. Timing problems due to variable transit delays through the MIN are dealt with by introducing Transient states in the proposed cache coherence protocol. The impact of the coherence protocol on system performance is evaluated through a performance study of three phases. Assuming homogeneity of all nodes, a single-node queuing model (phase 3) is developed to analyze system performance. This model is solved for processor and coherence bus utilizations using the mean value analysis (MVA) technique with shared-blocks steady state probabilities (phase 1) and communication delays (phase 2) as input parameters. The performance of our system is compared to that of a system with an equivalent-sized unified cache and with a multiprocessor implementing a directory-based coherence protocol. System performance measures are verified through simulation.

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We explore the consequences of the model of spin-down-induced flux expulsion for the magnetic field evolution in solitary as well as in binary neutron stars. The spin evolution of pulsars, allowing for their field evolution according to this model, is shown to be consistent with the existing observational constraints in both low- and high-mass X-ray binary systems. The contribution from pulsars recycled in massive binaries to the observed excess in the number of low-field (10(11)-10(12) G) solitary pulsars is argued to be negligible in comparison with that of normal pulsars undergoing a 'restricted' field decay predicted by the adopted field decay model. Magnetic fields of neutron stars born in close binaries with intermediate- or high-mass main-sequence companions are predicted to decay down to values as low as similar to 10(6) G, which would leave them unobservable as pulsars during most of their lifetimes. The post-recycling evolution of some of these systems can, however, account for the observed binary pulsars having neutron star or massive white dwarf companions. Pulsars recycled in the disc population low-mass binaries are expected to have residual fields greater than or similar to 10(8) G, while for those processed in globular clusters larger residual fields are predicted because of the lower field strength of the neutron star at the epoch of binary formation. A value of tau similar to 1-2 x 10(7) yr for the mean value of the Ohmic decay time-scale in the crusts of neutron stars is suggested, based on the consistency of the model predictions with the observed distribution of periods and magnetic fields in the single and binary pulsars.

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The Leipholz column which is having the Young modulus and mass per unit length as stochastic processes and also the distributed tangential follower load behaving stochastically is considered. The non self-adjoint differential equation and boundary conditions are considered to have random field coefficients. The standard perturbation method is employed. The non self-adjoint operators are used within the regularity domain. Full covariance structure of the free vibration eigenvalues and critical loads is derived in terms of second order properties of input random fields characterizing the system parameter fluctuations. The mean value of critical load is calculated using the averaged problem and the corresponding eigenvalue statistics are sought. Through the frequency equation a transformation is done to yield load parameter statistics. A numerical study incorporating commonly observed correlation models is reported which illustrates the full potentials of the derived expressions.