1st Component Research Articles

Optimization of pulse shape discrimination based on frequency domain for SiPM-based NaIL scintillator detector

Frequency gradient analysis (FGA) neutron-gamma pulse shape discrimination (PSD) based on Fourier transform has proved to be an effective method for discrimination between two types of pulses by simply constructing a discrimination parameter by subtracting the amplitude of the 1st frequency component from the 0th frequency component. However, the discrimination parameter constructed by the above method could not meet the requirements at some lower sample rates, and the dark noise caused using optoelectronic devices such as miniaturized SiPMs array further erodes the difference between the two frequency components. This paper proposes a new discrimination parameter construction method based on FGA for neutron-gamma discrimination, which is referred as mFGA (modified FGA). This discrimination parameter uses the 0th frequency component and other frequency components to enhance the discrimination performance. A neutron detector module consisting of a 25.4 mm× 25.4 mm× 50.8 mm NaI:Tl,6Li (NaIL) scintillator and an array of 8 × 8 SiPMs was established to verify the method of mFGA. The module measured a 252Cf neutron source under three shielding conditions: no shield, 5 cm high-density polyethylene (HDPE), and 10 cm lead brick. The proposed mFGA method was used to calculate the figure of merit (FoM) under each shielding condition and compared to the traditional frequency gradient method (FGA) and the traditional charge comparison method (CCM). The results show that the discrimination performance with the mFGA method is significantly improved. Taking the HDPE shielding group as an example, the performances of the three methods are FoM-FGA =1.14, FoM-mFGA =2.75, FoM-CCM =0.92. At the same time, with the increase of energy, due to the neutron gamma pulse becoming similar, and the discrimination performance of FGA and CCM decrease significantly. The discrimination performance of the mFGA method is relatively stable in all energy regions. Therefore, the proposed method is superior to the traditional FGA of the 0th frequency minus the 1st frequency and has a good application prospect for neutron-gamma discrimination with detectors of poor signal quality.

Ecophysiological difference in co-existing beech and oak saplings grown in different soil types under a free-air ozone exposure system

ABSTRACT To know effects of elevated ozone (eO3) response to beech (Fagus crenata) and oak (Quercus mongolica var. crispula) saplings, focusing on shoot elongation and leaf nutrient characteristics, beech and oak were grown in a free-air ozone-enrichment system (concentration: 35 ppb (aO3) vs. 75 ppb (eO3)) for two years under different soils (volcanic ash soil vs. brown forest soil). This treatment resulted in lower O3 tolerance in beech than in oak. The ratio of 2nd shoot flush showed a characteristic response to eO3 fumigation in beech and oak. For beech, the ratio was less than 0.5, while for oak, it ranged between 0.4 and 0.6. There was no difference in the photosynthetic rate of oak, although the photosynthetic rate of beech was slightly lower under elevated O3. Principal component analysis provided a good summary of the traits of beech and oak in response to O3 enrichment and soil combination, with O3-enriched beech characterized by higher Ca and lower N, P, K and A max in the 1st component and lower Mg and Mn in the 2nd component. O3 -treated oak in O3-enriched brown forest soils was characterized by high N, P, K and A max, while the influence of the 2nd component was small. Increased soil acidification will increase soil Mn and Al concentrations and may reduce the photosynthetic activity of beech saplings in eO3.

SBM vs VBM for highlighting similarities and differences between chronotype and Parkinson’s MRI scans: a preliminary analysis

Objective Voxel-Based Morphometry (VBM) and Source-Based Morphometry (SBM) are widely used techniques for analyzing structural Magnetic Resonance Imaging (MRI) data. VBM compares differences in gray and white matter volume, density, or concentration voxel-wise, while SBM identifies patterns of structural variation using independent component analysis. This study aims to compare the performance of VBM and SBM in detecting differences in brain structure across Parkinson’s patients and healthy controls, grouped based on their chronotype. Methods Thirty-three subjects were divided into three groups: a Parkinson’s Group (PG), an Early Chronotype Group (EG), and a Late Chronotype Group (LG). Circadian preference, daytime sleepiness, and sleep quality were assessed, and MRI data were acquired using a 3 T scanner. SBM and VBM were used to test differences and similarities in MRI scans and chronotypes. Results Results from SBM revealed significant clusters surviving the analysis, with the 1st component for the PG-EG and the 4th component for the PG-LG analysis showing the lowest p-value (< 0.05). Denser gray matter volume (GMV) or white matter volume (WMV) was observed in the Middle Frontal Gyrus and the Lentiform Nucleus through Talairach Coordinates analysis. Conclusions This study emphasizes the importance of selecting appropriate methods for analyzing structural MRI data. VBM is effective in identifying local differences in brain structure, while SBM provides a more comprehensive view of structural variation, detecting patterns not captured by VBM. Future studies should consider utilizing both VBM and SBM to fully characterize brain structural differences in diverse clinical and cognitive populations. Further studies, with larger sample sizes and more balanced genders, genomic analysis, disease severity and duration, as well as medications’ effect, are warranted.

Effect of COVID-19 vaccination on the immune status and autoantibody profile in women of reproductive age

In the context of the COVID-19 pandemic, scientific interest is growing in studying the impact of the proposed vaccination on women’s reproductive health. As is known, alterations in the state of the immune system and activation of an autoimmune response can lead to reproductive failure in women and potential complications of subsequent pregnancy. Objective: to evaluate the effect of the “Gam-COVID-Vac” on the immune status parameters, the relationship of their changes and the specific immune response to vaccination with the dynamics of the level of autoantibodies in women of reproductive age.The prospective study included 120 women who were vaccinated against COVID-19 with the “Gam-COVIDVac”. The criteria for inclusion in the study were: the age from 18 to 49 years, the absence of COVID-19 in the anamnesis, a negative result of a study on SARS-CoV-2 by PCR and negative results of tests for antibodies of classes G and M to SARS-CoV-2 before vaccination, the absence of pregnancy and serious somatic diseases. The patients were examined twice: immediately before vaccination and 90-100 days after the introduction of the 1st component of the vaccine. The level of IgG antibodies to SARS-CoV-2 after vaccination was assessed using ELISA. Before and after vaccination, the levels of antiphospholipid, anti-nuclear, organ-specific and antihormonal autoantibodies were determined, peripheral blood lymphocytes were immunophenotyped to determine the main subpopulations (CD3, CD4, CD8, CD19, CD5, CD16, CD56), as well as the expression of activation markers of lymphocytes (HLA-DR, CD25, CD147) using monoclonal antibodies.The effectiveness and safety of the combined vector vaccine against COVID-19 were high. Specific IgG antibodies to SARS-CoV-2 were produced in 98.3% of vaccinated women, no serious adverse reactions were observed. After vaccination, there was an increase in the level of some autoantibodies within the reference ranges, only IgM antibodies to phosphatidylethanolamine (PE) and IgG antibodies to DNA increased above the reference values. However, this increase was transient. After vaccination, the following changes in the parameters of the immunogram were observed: an increase in the content of cells with CD3+CD25+, CD19+ phenotype in peripheral blood and a decrease in the content of cells with CD56+CD16+ phenotype within the reference ranges, a decrease in CD147+/CD3+. Weak correlations were noted between these changes in immunogram parameters and the levels of some autoantibodies. The specific antiviral immune response to vaccination did not correlate with the autoimmune response.Vaccination with “Gam-COVID-Vac” is effective and safe and does not lead to disorders in the immune system. The observed increase in the level of autoantibodies to PE and DNA is transient. Changes in the parameters of the immune status within the reference ranges may be due to vaccination and the development of a specific antiviral immune response.

541. DO WE NEED ANOTHER QUESTIONNAIRE FOR GASTRO-ESOPHAGEAL REFLUX DISEASE? PRELIMINARY ANALYSIS OF A NEW QUESTIONNAIRE

Abstract Gastroesophageal reflux is a very frequent condition and different questionnaires to describe it have been proposed overtime. Nevertheless available questionnaires don’t allow to fully describe all different aspects of the disease. The aim of this study was to validate a new questionnaire (RoRex) on gastroesophageal reflux disease. The RoRex questionnaire was administered via web in two Italian centres, Rovereto and Verona, to patients attending specialized gastrointestinal surgical units, and to volunteers. Up to now, 54 patients and 50 volunteers participated in the study. Median age was 52 years (range 23-75 years) in patients and 47.5 years (range 25-80 years) in volunteers. Women were more prevalent than men in both groups (57% and 56% respectively). The RoRex questionnaire comprises 15 questions, where symptoms are scored on a frequency base: no, sometimes, several times per week, every day. Information on smoking habits, alcohol use, diet was also collected. The two groups largely differed as regards major symptoms. Regurgitation, heartburn, epigastric pain, retrosternal pain, laryngospasm were reported several times per week/every day in 50%, 39%, 30%, 22%, 23% of patients and 9%, 11%, 7%, 7%, 0% of volunteers. Preliminary analysis showed a different pattern in principal components between patients and volunteers. The 1st component, comprising heartburn and epigastric/retrosternal pain, was similar in both groups. The 2nd component comprised reclage, peevish cough, hoarseness in patients, and postnasal drip, hoarseness, dysphagia in volunteers. The 3rd component included regurgitation/laryngospasm in the former and peevish cough/belching in the latter. The new questionnaire, based on symptom frequency, allows to distinguish among major symptoms, i.e. heartburn/pain, upper airways irritation, and regurgitation in patients suffering from gastroesophageal reflux disease. These results, as well as the comparison of RoRex questionnaire with already validated ones and its usefulness as a screening tool in the general population, will be verified in larger samples.

A torque ripple reduction method using field current injection for doubly salient motor

Doubly salient motor (DSM) is widely used owing to attractively in high-speed operation capability. However, there is a shortcoming of torque ripple for the non-sinusoidal nonlinear structure, for the purpose of solving this problem, this paper presents a torque ripple reduction strategy by field current injection for doubly salient motor. Initially, the armature current control method of the DSM adopts the multi-sine superposition (MSWS) driving scheme, combined with finite element and Fourier analysis methods to establish the output torque and torque ripple model, where the torque of the DSM is mainly composed of the 1st, 2nd, and 4th harmonic component, and the torque ripple is mainly composed of 3rd harmonics component. Then, a field current injection approach is presented, and calculate the magnitude and phase of the injected component, which serves as a quantitative analysis foundation for torque ripple suppression. Finally, the experimental results illustrate the superiority of the presented method in torque ripple optimization.

Surface-enhanced Raman spectral analysis for comparison of PCR products of hepatitis B and hepatitis C

BackgroundSurface-enhanced Raman spectroscopy is a reliable tool for identification and differentiation of two diseases showing similar symptoms, hepatitis B (HBV) and hepatitis C (HCV). ObjectivesTo develop a polymerase chain reaction technique (PCR) based SERS technique for differentiation of two human pathological conditions sharing the same symptoms using multivariate data analysis techniques e.g. principle component analysis (PCA) and partial least square discriminate analysis (PLS-DA). MethodsPCR products of HBV and HCV were differentiated by SERS using silver nanoparticles (AgNPs) as a SERS substrate. For this analysis, PCR products of both the diseases with predetermined viral loads were collected and analyzed under SERS instrument and unique SERS spectra of HBV and HCV was compared showing many differences at various points. Diseased classes of HBV and HCV and their negative control classes (viral load less than 1) were compared. PCR products of true healthy DNA and RNA were also compared, which were significantly separated. Moreover, SERS data was analyzed using multivariate data analysis techniques including principle component analysis (PCA) and partial least square discriminate analysis (PLS-DA) and differences were so prominent to observe. ResultsSERS spectral data of HBV and HCV showed clear differences and were significantly separated using PCA. Negative control samples of both disorders and their true healthy samples of DNA and RNA were separated according to 1st principle component. By analyzing data using partial least square discriminate analysis, differentiation of two disease classes was considered more valid with sensitivity, specificity and accuracy value of 96%, 94% and 98% respectively. Value of area under curve (AUROC) was 0.7527. ConclusionSERS can be employed for identification and comparison of two human pathological conditions sharing the same symptomology.

Surface-enhanced Raman spectroscopy for comparison of serum samples of typhoid and tuberculosis patients of different stages

BackgroundSurface-enhanced Raman spectroscopy (SERS) is a reliable tool for the identification and differentiation of two different human pathological conditions sharing the same symptomology, typhoid and tuberculosis (TB). ObjectivesTo explore the potential of surface-enhanced Raman spectroscopy for differentiation of two different diseases showing the same symptoms and analysis by principal component analysis (PCA) and partial least square discriminate analysis (PLS-DA). MethodsSerum samples of clinically diagnosed typhoid and tuberculosis infected individuals were analyzed and differentiated by SERS using silver nanoparticles (Ag NPs) as a SERS substrate. For this purpose, the collected serum samples were analyzed under the SERS instrument and unique SERS spectra of typhoid and tuberculosis were compared showing notable spectral differences in protein, lipid and carbohydrates features. Different stages of the diseased class of typhoid (Early acute and late acute stage) and tuberculosis (Pulmonary and extra-pulmonary stage) were compared with each other and with healthy human serum samples, which were significantly separated. Moreover, SERS data was analyzed using multivariate data analysis techniques including principal component analysis (PCA) and partial least square discriminate analysis (PLS-DA) and differences were so prominent to observe. ResultsSERS Spectral data of typhoid and tuberculosis showed clear differences and were significantly separated using PCA. SERS spectral data of both stages of typhoid and tuberculosis were separated according to 1st principle component. Moreover, by analyzing data using partial least square discriminate analysis, differentiation of two disease classes were considered more valid with a 100% value of sensitivity, specificity and accuracy. ConclusionSERS can be employed for identification and comparison of two different human pathological conditions sharing same symptomology.

Multimodal optical excitation pulsed thermography: Enhanced recognize debonding defects of the solid propellant rocket motor cladding layer

We demonstrated the multimodal optical excitation pulsed thermography, and this technique can enhance the defect detectability and the depth-resolution dynamic range for the propellant /cladding layer interface debonding defects of the solid propellant rocket motor. Firstly, three-dimensional (3D) thermal-wave model which stimulated by a pulse excitation thermal source was built. The temperature field distribution and the thermal-wave diffusion behavior were analyzed. Subsequently, multiple feature extraction algorithms were proposed and applied to extract characteristic images. The experimental set-up was developed and utilized to detect cladding layers with artificial defects. The results demonstrate that pulse thermography optimized by PLSR and ICA can achieve better detection of interface debonding defects. The characteristic profiles were analyzed to evaluate the ability of feature images to characterize the defect diameter and depth. The results depict that the 1st independent component has a better detection effect for defect depth and diameter.

Exploration of the Specificity of Motor Skills Hypothesis in 7-8 Year Old Primary School Children: Exploring the Relationship Between 12 Different Motor Skills From Two Different Motor Competence Test Batteries.

This study examined the specificity hypothesis by examining the association between two specific motor competence test batteries [Movement Assessment Battery for Children (MABC) and Test of Motor Competence (TMC)] in a sample of young children. In addition, we explored the factorial structure of the MABC and TMC. A total of 80 children participated in the study (38 girls and 42 boys) with a mean chronological age of 7.9 years (SD 0.55). The correlation between total score MABC and total z-score TMC was r = 0.46. In general, low pair-wise correlations (r2 < 0.20) between the different motor tasks were found. The highest correlation was between the placing bricks and building bricks r = 0.45 (TMC); the stork balance and jumping in squares r = 0.45 (MABC). These low pair-wise relations of items are consistent with findings from younger and older children's age-related motor competence test batteries. Principal components analysis (PCA) showed that the 1st component accommodated 25% of the variance and was dominated in the top five variable weightings by items of the MABC test; whereas the 2nd component accommodated 12% of the variance with the higher weightings all from the TMC test. The findings provide evidence with children for specificity rather than generality in learning motor skills a viewpoint that has predominantly been driven by adult learning studies. The PCA revealed that the MABC and TMC are testing different properties of children's motor competence though in both cases the variance accounted for is relatively modest, but generally higher than the motor item pair-wise correlation.

Hydropedological behavior of a chromic vertisol under different plant covers

Vertisols present edaphic limiting factors primarily of a physical nature. The study of their hydropedology, supported by multivariate techniques, is of vital importance. The work was developed with the objective of determining, through multivariate analysis, the hydropedological behavior of a Chromic Vertisol under different plant covers. In areas under natural grass, sugarcane, and secondary forest, belonging to the Holguín Sugarcane Provincial Research Station, three random points were chosen in each. Soil penetration resistance, soil bulk density, gravimetric moisture, and volumetric moisture at depths of 0-10, 10-20 and 20-30cm were determined. A Principal Component Analysis and Canonical Correlations were performed using Statistica 7 and Statgraphics Plus XV.II. The first two components made the greatest contribution to the variance, with 83.09%. The greatest contributions (1st component) were given by moisture at all depths and by soil compaction at a depth of 20-30 cm. The 2nd component was influenced by soil compaction in the 0-10 and 10-20cm layers. There was a contrast between the variables that characterize the solid phase with which they describe the liquid phase of the soil. There was a correlation between soil moisture and compaction. The first two pairs of canonical variables showed a strong linear correlation and regularly dispersed along the central values of the model, with a remarkable grouping by depths.

Factors affecting night sleep in rotational shift workers in the Arctic

Abstract Funding Acknowledgements Type of funding sources: None. Background Our previous studies revealed that half of arterial hypertension (AH) patients had a flat type of non-dipper curve of blood pressure daily profile (BPDP). Purpose To study and differentiate the leading component of sleep disturbance in conditions of the Arctic rotational shift work and evaluate its relationship with the data of ambulatory blood pressure monitoring (ABPM). Methods In September 2019, 180 patients with AH, including 79 males (M), (gr. 1) aged 48.7 ± 8.3 years and 68 females (F), (gr. 2) aged 50.0 ± 6.7 years (p = 0.06) were simultaneously examined in Yamburg (68 N) settlement in the Arctic Watch. Groups did not differ in rotational shift work duration (16.9 ± 8.7 and 16.2 ± 8.3 years, p = 0.72). Analysis of sleep quality (Pittsburg Sleep Quality Index - PSQI) with daytime sleepiness analysis (Epworth Sleepiness Scale) was carried out. Six components were investigated: 1 - subjective sleep (S) quality component; 2 - assessment of S latency; 3 - assessment of S duration; 4 – habitual S efficiency ; 5 – step disturbances of S; 6 - use of S medication; 7 - daytime S dysfunction with differentiation of global index (Global PSQI score). All individuals underwent ABPM with analysis of daily index of systolic blood pressure and diastolic blood pressure and BPDP. Results According to the survey, 22% had S disorders in M gr., 30% (24/81) in F gr., p = 0.23. Global assessment of S quality was also not dependent on gender: mode of assessment was 4 points (P), (24 individuals) in M, 5 P (17) in F (p = 0.91). Leading components of S quality disorder were the subjective S quality with 2 P, (16); the S latently had 2 P (11); the step disturbances of S had the 2 P (11) and the daytime S dysfunction had the 2 P (14) in M. In F, the 1st component (C)C (2 P – 13); the 2nd C - 2 P (16) prevailed and the 5th and the 7th C were less manifested. Moreover, F had S latency complaints oftener than M (p = 0.031). Analysis of interconnections with ABPM revealed "over dipper" BPDP in the 12.5%, "dipper" BPDP in 42.5% (51); "non dipper" BPDP in 41.7% (50); "night peaker" BPDP in 3.3%. In individuals with normal S quality, "dipper" BPDP prevailed (54%). At the same time, leading components did not have significant correlations with abnormal BPDP. Conclusion In conditions of rotational shift work in the Arctic, regardless of gender, sleep disturbances are more associated with poor habitual sleep efficiency and less associated with disturbances of BPDP. This is obviously explained by increased exhaustion due to the intense nature of rotational shift work in the Arctic region.

A pedaling force vector can be represented by the sum of three elemental force vector waveforms.

B ackground & Purpose: In recent years, we have become able to accurately measure the pedaling force vector using pedaling analyzer (Bikefitting.com, Sittard, Netherlands) or pedaling monitoring (Pioneer Corporation, Kawasaki, Japan) systems. Using these devices, mechanical pedaling characteristics can be calculated from the pedaling force vector and expressed as an efficiency index or torque effectiveness, which is also calculated from the tangential force profile during pedaling. However, these indicators only demonstrate the mechanical characteristics of pedaling and are not based on body movement. Hence, we aim to analyze the pedaling force vector waveform based on biomechanical pedaling motion. A previous study analyzing the EMG signals of the lower limb muscles demonstrated that, in trained cyclists, pedaling is accomplished by combining three similar muscle synergies. (Is interindividual variability of EMG patterns in trained cyclists related to different muscle synergies? J Appl Physiol, 108(6) 1727-36. 2010). This study expresses the pedal force vector waveform obtained from the pedaling force analyzer system by the sum of element force vector waveforms. Methods: Two participants (a former professional and a top-level amateur cyclist) were given a variety of pedaling conditions (load: 100, 200, 300 W; cadence: 70, 90, 110 rpm; saddle position: back (5 mm), forward (10 mm), up (3 mm), and down (5, 10 mm); pedaling action type: normal, spinning, pulling and pushing and pulling). Pedaling force vector data was obtained every 15 degrees using a pedaling analyzer system (Bikefitting.com). Pedaling vector data were expressed as the sum of elemental vectors. Common elemental vector waveforms and parameters were determined so that the root mean square error between the sum of the elemental vector waveforms and the original vector data were minimized by changing the amplitude and phase difference. The pedaling vector data and parameters can be expressed numerically with the following equation: . R esults & Discussion: The force vector component in the tangential direction can be represented by the sum of two waveform components, excluding the constant average force, as shown in Figure 1. At this time, the shapes of the wave functions ( f 1 : 1st and f 2 : 2nd component) are fixed; only their amplitude and phase angle change. In contrast, the radial direction of the vector component can be represented by the sum of three waveforms: two correspond to the amplitude and phase angle of the two waves expressed in the tangential direction, and the remaining one has an independent amplitude and phase angle. The scatter diagram in Figure 2 was created using A 1 and A 2 , which are the amplitudes of the 1st and 2nd component of functions obtained by resolving the vector component of the tangential direction. Using this scatter diagram, we can classify pedaling characteristics. This result indicates that pedaling action can be represented by up to three elemental motions, which may correspond to muscle behavior expressed by three synergies. Importantly, this study accounted for the waveform’s phase angle change. In the future, we will investigate the difference between change in the element waveform and muscle force assessment, and will study the corresponding muscle force strength and pedaling action. Conclusion: Pedaling force vector components in the tangential and radial directions, obtained by a pedaling analyzer system, can be represented by the sum of two or three elemental waveform components, respectively.

Morphological Contributions to Interfacial Charge Trapping and Nongeminate Recombination in Polymer Solar Cells Revealed by UV Light Soaking.

Nongeminate charge recombination occurs over a broad range of time scales in polymer solar cells and represents a serious loss channel for the performance and lifetime of devices. Multiple factors influence this process, including changes in morphology and formation of permanent defects, but individual contributions are often difficult to resolve from conventional experiments. We use intensity modulated photocurrent/photovoltage spectroscopy (IMPS/IMVS) to investigate nongeminate charge recombination in blends of poly[2,6-(4,4-bis-(2-ethylhexyl)-4 H-cyclopenta [2,1- b;3,4- b']dithiophene)- alt-4,7(2,1,3-benzothiadiazole)] (PCPDTBT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) solar cells. PCPDTBT/PCBM devices are exposed to varying doses of UV light resonant with PCBM to induce small perturbations in the thin film morphology, namely local heating. IMPS/IMVS sweeps display signatures unique to degradation, that is, photocurrent and photovoltage leading the excitation light modulation appearing as positive phase shifts or 1st quadrant features in Bode and Nyquist representations, respectively. We assign this component to interface charging at purified PCPDTBT/PCBM phase boundaries that trap mobile charges and facilitate nongeminate recombination. Time- and frequency-domain drift-diffusion simulations are then used to model the perturbed photocurrent responses that show good agreement with experiments. Trap occupancies and their impact of photocurrent production are investigated using variable background (dc) excitation light intensities revealing increases of the 1st quadrant component in devices irradiated for longer times. No evidence of chemical degradation was observed from molecular spectroscopy and imaging experiments, and we conclude that morphological changes are chiefly responsible for larger nongeminate charge recombination yields as devices age. Lastly, we propose that the 1st quadrant IMPS/IMVS is a universal signature of morphology-related degradation, although its relative contribution may vary between material systems.

Gluteal activation and increased frontal plane projection angle during a step-down test in young women

PurposeTo investigate how the activation of gluteus maximus and gluteus medius interacts with different frontal plane projection angles (FPPA) in healthy young women presenting dynamic knee valgus in one limb while performing the step-down test.MethodsThe total of 18 young women presenting FPPA &gt; 15° during the step-down test in one limb (dynamic knee valgus) were assessed. The other limb should present less than 15° for comparisons. The amplitude of muscle activation was assessed through surface electromyography of gluteus medius and gluteus maximus during 8 subsequent weight bearing step-down tests.ResultsFPPA was positively correlated with gluteus maximus activation and with the assessed side showing FPPA &gt; 15°, which also revealed increased activation of gluteus maximus. No differences were noted for gluteus medius. The principal component analysis explained 73% of the variance in 2 components, with gluteus maximus explaining 48% of the variance on the 1st component. Gluteus medius explained 25% on the 2nd component.ConclusionsGluteus maximus seems to be a major component to explain dynamic knee valgus in women without symptoms of patellofemoral pain, probably owing to weakness and lack of stabilization of other proximal muscles of the hip-knee complex during the task.

Nonlinear theory considering harmonic interaction using Eulerian hydrodynamic analysis

Traveling wave tube amplifiers are one of the most widely used vacuum electronic devices which are employed in various applications, in the areas of such as radar, wireless communication and electronic countermeasures system. Among traveling wave tubes, space-borne helix traveling wave tubes which are of high power, high efficiency, high reliability, long life and radiation hardened, are extensively used in satellite transmitter, data communication system and global positioning system. With the rapid development of the multiphase digital modulation schemes, communication systems are placing greater demands on the output power, electronic efficiency and nonlinear distortion characteristics of space-borne helix traveling wave tubes. However, the nonlinear beam-wave interaction will lead to the generation of harmonics, and thus reduces the output power and electronic efficiency. The harmonics can also act to create beats with the fundamental wave, and thus generate these beat frequencies which are commonly known as intermodulation products. As a result, the bit-error-rate will be increased and the system performance will be compromised. Therefore, the generation of harmonics is of significant current interest in space-borne helix traveling wave tubes. Understanding this effect provides a strong motivation for nonlinear analysis of a helix traveling wave tube. In this paper, a continuous electron phase distribution is obtained by treating the discrete electron beam as a charge fluid based on the Lagrangian theory. Then, to obtain a nonlinear Eulerian theory considering harmonic interaction, the electron phases in Lagrangian theory have been expanded into a series of harmonic components. Considering the 0th component and 1st component of the electron phases only and integrating over the initial phase distribution with the help of the relation of Bessel function, the nonlinear Eulerian theory considering harmonic interaction is established. The nonlinear Eulerian theory considering harmonic interaction is compared to a Lagrangian theory on a set of traveling wave tube parameters which are based on a single section of L-and C-bands traveling wave tubes. It is found that the nonlinear Eulerian theory considering harmonic interaction agrees accords well with the Lagrangian theory before the saturation effect occurs. But, it begins to make a difference near saturation point where the electron overtaking happens. The maximum error in gain between the nonlinear Eulerian theory considering harmonic interaction and the Lagrangian theory is less than 4% at 1 dB gain compression point. So the present nonlinear Eulerian theory considering harmonic interaction can effectively describe harmonic generation at 1 dB gain compression point. The simulation results validate the correctness and effectiveness of our nonlinear Eulerian theory considering harmonic interaction. In futuristic future efforts, it is hoped that the present nonlinear Eulerian theory considering harmonic interaction may provide insights into the behavioral mechanisms of nonlinear effects in space-borne helix traveling wave tubes.

CT imaging features associated with recurrence in non-small cell lung cancer patients after stereotactic body radiotherapy

BackgroundPredicting recurrence after stereotactic body radiotherapy (SBRT) in non-small cell lung cancer (NSCLC) patients is problematic, but critical for the decision of following treatment. This study aims to investigate the association of imaging features derived from the first follow-up computed tomography (CT) on lung cancer patient outcomes following SBRT, and identify patients at high risk of recurrence.MethodsFifty nine biopsy-proven non-small cell lung cancer patients were qualified for this study. The first follow-up CTs were performed about 3 months after SBRT (median time: 91 days). Imaging features included 34 manually scored radiological features (semantics) describing the lesion, lung and thorax and 219 quantitative imaging features (radiomics) extracted automatically after delineation of the lesion. Cox proportional hazard models and Harrel’s C-index were used to explore predictors of overall survival (OS), recurrence-free survival (RFS), and loco-regional recurrence-free survival (LR-RFS). Five-fold cross validation was performed on the final prognostic model.ResultsThe median follow-up time was 42 months. The model for OS contained Eastern Cooperative Oncology Group (ECOG) performance status (HR = 3.13, 95% CI: 1.17–8.41), vascular involvement (HR = 3.21, 95% CI: 1.29–8.03), lymphadenopathy (HR = 3.59, 95% CI: 1.58–8.16) and the 1st principle component of radiomic features (HR = 1.24, 95% CI: 1.02–1.51). The model for RFS contained vascular involvement (HR = 3.06, 95% CI: 1.40–6.70), vessel attachment (HR = 3.46, 95% CI: 1.65–7.25), pleural retraction (HR = 3.24, 95% CI: 1.41–7.42), lymphadenopathy (HR = 6.41, 95% CI: 2.58–15.90) and relative enhancement (HR = 1.40, 95% CI: 1.00–1.96). The model for LR-RFS contained vascular involvement (HR = 4.96, 95% CI: 2.23–11.03), lymphadenopathy (HR = 2.64, 95% CI: 1.19–5.82), circularity (F13, HR = 1.60, 95% CI: 1.10–2.32) and 3D Laws feature (F92, HR = 1.96, 95% CI: 1.35–2.83). Five-fold cross-validated the areas under the receiver operating characteristic curves (AUC) of these three models were all above 0.8.ConclusionsOur analysis reveals disease progression could be prognosticated as early as 3 months after SBRT using CT imaging features, and these features would be helpful in clinical decision-making.

Developmental trajectories of event related potentials related to working memory

Working memory is an important cognitive function, and it is crucial to better understand its neurophysiological mechanisms. The developmental trajectories of the Event Related Potentials related to this important function have hardly been studied. However, these ERPs may provide some clues about the individual state of maturation, as has been demonstrated for anatomical brain images.The present study aims to determine the behavioral and neurophysiological development of Working Memory (WM) processes. For this purpose, 170 subjects with ages ranging from 6 to 26 years performed a visual Delayed Match-to-Sample task (DMTS). The RTs, total errors, and Event Related Potentials (ERPs) in the phases of encoding, retention, and matching were obtained. Results revealed a decrease in the amplitude of ERPs with age, paralleled by improved performance on the DMTS task (i.e., shorter RTs and fewer errors). None of these variables were affected by gender. To determine whether memory performance was influenced by the individual pattern of maturation beyond age, the amplitude of the different ERP components was correlated with RT and errors on the WM task after removing the effect of age. Frontal N2 and posterior P1 and the Late Positive Component were the only ERPs that presented significant correlations with behavioral errors. Behavioral performance was predicted by age and by the scores on the first component extracted from Principal Component Analysis (PCA) of the ERPs. Age (under 17 years old) explained 85.04% and the PCA component explained 14.96% of the variance explained by the bivariate model predicting behavioral errors (1/age + scores of 1st PCA component). From the age of 17 on, the principal PCA component ceases to be an independent component predicting error performance. The results suggest that the individual maturation of ERP components seems to be of particular importance in controlling behavioral errors in WM, as measured by the DMTS.

P30. Experience feedback of a radiation protection incident in radiotherapy: Irradiation of a pregnant patient

Introduction A woman, treated by radiotherapy in the Centre Francois Baclesse in Caen for a head and neck cancer was proving pregnant (3rd month of pregnancy during the treatment).The pregnancy was revealed after the completion of the treatment (30 fractions – 2 Gy / fraction).In order to know the dose received by the fetus, measurements have been achieved with identical conditions as for the treatment. Materials and methods Irradiation technique:VMAT on a Clinac iX (Varian) linac.2 arcs of 307 UM and 278 UM with 6 MV photons.Phantom:Compact polystyrene to simulate the body and head and neck cylindrical phantom to simulate the irradiated volume.The ionization chamber was positioned at 45 cm of the field edge.This distance was measured by the medical doctor on the patient.The measurements were achieved with the same parameters recorded on the ”record and verify” software (Mosaiq – Elekta).The measurement cumulated 5 repetitions to improve the accuracy. Results For 1 fraction:0.83 mGy For the whole treatment (30 fractions):24.9 mGy Discussion 1/The dose far from the irradiation field has 3 components [1] -Photons scattered by the irradiated volume of the patient (internal) -Photons scattered by the irradiated materials (couch) and the walls of the treatment vault -Leakage radiation from the linac 2/The 1st component of the dose (scattered photons inside the patient) is very low because of the large distance between the field edge and the measuring point.In the ICRP report #84 (Pregnancy and medical radiation) [2] off axis values of dose are given for cobalt 60:approximately 0.25% at 45 cm but for linacs this off axis dose is lower 2–5 times (depending on beam energy).Our measurements (0.04%) are so, in good agreement with the ICRP #84 data.In the literature, several authors reported equivalent fetal doses for head and neck irradiations [3] [4] [7] .For irradiated volumes closer to the uterus (Hodgkin desease), the doses are obviously much greater [5] [6] . Conclusion The value of the effective dose measured ( ≈ 25 mSv) is superior to the upper legal limit for the fetus (1 mSv). In consequence, this case was declared as an incident to the French Nuclear Safety Authority (ASN) but it is assumed not to be critical for the children: – Malformations have a threshold of 100–200 mGy or higher and are typically associated with central nervous system problems [1] – A fetal dose of 100 mGy has a small individual risk of radiation-induced cancer. There is over a 99% chance that the exposed fetus will NOT develop childhood cancer or leukaemia [2]

Taxonomic position of Chinese voles of the tribe Arvicolini and the description of 2 new species from Xizang, China.

China has 26 species in the tribe Arvicolini. The taxonomic status of these voles remains controversial despite much effort. Herein, we evaluate the taxonomic position of 22 species plus 2 unidentified taxa using mitochondrial DNA gene sequences (cytb + CO1). We also evaluate 18 species and 2 unidentified taxa using morphological data. Phylogenetic analyses of cytb resolve monophyly for the genera Alexandromys, Lasiopodomys, Microtus, Neodon, Proedromys, and Volemys with strong support. Stenocranius clusters with Chionomys but with very weak support. Analyses of concatenated cytb + CO1 resolve the same genera with strong support, but the topology of the tree differs from that of cytb in that Chionomys roots at the base of the tree independent of Stenocranius, which forms the sister-group of Lasiopodomys in a more terminal position. The matrilineal genealogy excludes the type species Arvicola amphibius from the rest of the Arvicolini. This species forms the sister-group of Ondatra with high support. Neodon includes N. irene, N. linzhiensis, N. fuscus, N. leucurus, N. sikimensis, Microtus clarkei, and 2 unidentified specimens. Alexandromys includes the former species Microtus oeconomus, M. kikuchii, M. limnophilus, M. fortis, and M. maximowiczii. Finally, Microtus has the subgenera Blanfordimys, Microtus, Mynomes, Pedomys, Pitymys, and Terricola, which includes the Chinese species M. agrestis, M. arvalis, and Blanfordimys juldaschi. General mixed Yule-coalescent species delimitation modeling demarcates 6 currently recognized species and 2 new species of Neodon. A principal component analysis of the morphological data among 7 matrilines shows that all variables have positive loadings of high magnitude on the 1st component. Canonical discriminant analysis for Neodon (including M. clarkei and 2 unidentified species) correctly classifies 93.0% of specimens. Overall, our analyses support the recognition of Alexandromys, Lasiopodomys, Microtus, Neodon, Proedromys, and Volemys as genera. Stenocranius includes Microtus gregalis, and the genealogical position of Stenocranius remains uncertain. The status of Arvicola requires further study. We assign M. clarkei to Neodon and describe 2 new species of Neodon.