relative variable
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2021 ◽  
Vol 11 (21) ◽  
pp. 10396
Author(s):  
Xiaogang Guo ◽  
Peiwen Hao

Potential damage, eventually demonstrated as moisture damage on inner and in-situ road structures, is the most complex problem to predict, which costs lots of money, time, and natural resources for maintenance and even leads to safety problems. Traditional linear regression analysis cannot fit well with this multi-factor task in such in-field circumstances. Random Forest (RF) is a progressive nonlinear algorithm, which can combine all relative factors to gain accurate prediction and good explanation. In this study, an RF model is constructed for the prediction of potential damage. In addition, relative variable importance is analyzed to obtain the correlations between factors and potential damage separately. The results show that, through the optimization, the model achieved a good average accuracy of 83.33%. Finally, the controlling method for moisture damage is provided by combining the traditional analysis method and the RF model. In a word, RF is a prospective method in predictions and data mining for highway engineering. Trained with effective data, it can be multifunctional and powerful to solve hard problems.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Julian Reimer ◽  
Sebastian Stöcklin ◽  
Laura M. Comella ◽  
Peter Woias ◽  
Christiane Werner ◽  
...  

Abstract Measuring chlorophyll fluorescence is an important tool in plant research, since it is a reliable non-invasive method for capturing photosynthetic efficiency of a plant and, hence, an indicator of plant stress/health. The principle of chlorophyll fluorometry is based on the optical illumination of a plant’s leaf at a certain wavelength, while simultaneously measuring the emitted fluorescence light intensity at a different optical wavelength. By relating the fluorescence light energy at small and large excitation power, conclusions on the efficiency of the photosystem and, therefore, on the plant’s photosynthesis capability can be drawn. Current mobile chlorophyll fluorometers are either (i) compact and energy efficient but limited in functionality and accuracy by omitting modulated measurement signals or (ii) sophisticated and precise with respect to the measurement, but with the drawback of extended weight, size, energy consumption and cost. This contribution presents a smaller, lighter and cheaper sensor device that can be built with sufficiently low energy consumption to be powered by energy harvesting while being light enough to be attached nearly anywhere such as tree branches. With a device cost below 250 €, the performance of the developed device is similar to more expensive commercial devices considering measurements of the relative variable fluorescence. Moreover, the sensor device provides a wireless interface in the European 868 MHz SRD band with up to 10 km of range in free space while just consuming 150 µW in receiving mode due to a custom duty cycling technique.


2021 ◽  
Vol 12 ◽  
Author(s):  
Xianjun Chen ◽  
Yan Zhou ◽  
Yundan Cong ◽  
Pusheng Zhu ◽  
Jiayi Xing ◽  
...  

In this study, the protective role of exogenous ascorbic acid (AsA) on salt-induced inhibition of photosynthesis in the seedlings of processing tomatoes under salt stress has been investigated. Plants under salt stress (NaCl, 100 mmol/L) were foliar-sprayed with AsA (0.5 mmol/L), lycorine (LYC, 0.25 mmol/L, an inhibitor of key AsA synthesis enzyme l-galactono-γ-lactone dehydrogenase activity), or AsA plus LYC. The effects of AsA on fast OJIP fluorescence rise curve and JIP parameters were then examined. Our results demonstrated that applying exogenous AsA significantly changed the composition of O-J-I-P fluorescence transients in plants subjected to salt stress both with and without LYC. An increase in basal fluorescence (Fo) and a decrease in maximum fluorescence (Fm) were observed. Lower K- and L-bands and higher I-band were detected on the OJIP transient curves compared, respectively, with salt-stressed plants with and without LYC. AsA application also significantly increased the values of normalized total complementary area (Sm), relative variable fluorescence intensity at the I-step (VI), absorbed light energy (ABS/CSm), excitation energy (TRo/CSm), and reduction energy entering the electron transfer chain beyond QA (ETo/CSm) per reaction centre (RC) and electron transport flux per active RC (ETo/RC), while decreasing some others like the approximated initial slope of the fluorescence transient (Mo), relative variable fluorescence intensity at the K-step (VK), average absorption (ABS/RC), trapping (TRo/RC), heat dissipation (DIo/RC) per active RC, and heat dissipation per active RC (DIo/CSm) in the presence or absence of LYC. These results suggested that exogenous AsA counteracted salt-induced photoinhibition mainly by modulating the endogenous AsA level and redox state in the chloroplast to promote chlorophyll synthesis and alleviate the damage of oxidative stress to photosynthetic apparatus. AsA can also raise the efficiency of light utilization as well as excitation energy dissipation within the photosystem II (PSII) antennae, thus increasing the stability of PSII and promoting the movement of electrons among PS1 and PSII in tomato seedling leaves subjected to salt stress.


Author(s):  
XD Dongfang

Einstein's assumption that the speed of light is constant is a fundamental principle of modern physics with great influence. However, the nature of the principle of constant speed of light is rarely described in detail in the relevant literatures, which leads to a deep misunderstanding among some readers of special relativity. Here we introduce the unitary principle, which has a wide application prospect in the logic self consistency test of mathematics, natural science and social science. Based on this, we propose the complete space-time transformation including the Lorentz transformation, clarify the definition of relative velocity of light and the conclusion that the relative velocity of light is variable, and further prove that the relative variable light speed is compatible with Einstein's constant speed of light. The specific conclusion is that the propagation speed of light in vacuum relative to the observer's inertial reference frame is always constant $c$, but the propagation speed of light relative to any other inertial reference frame which has relative motion with the observer is not equal to the constant $c$; observing in all inertial frame of reference, the relative velocity of light propagating in the same direction in vacuum is $0$, while that of light propagating in the opposite direction is $2c$. The essence of Einstein's constant speed of light is that the speed of light in an isolated reference frame is constant, but the relative speed of light in vacuum is variable. The assumption of constant speed of light in an isolated frame of reference and the inference of relative variable light speed can be derived from each other.


2020 ◽  
Vol 49 (6) ◽  
pp. E19
Author(s):  
Francesco Doglietto ◽  
Marika Vezzoli ◽  
Antonio Biroli ◽  
Giorgio Saraceno ◽  
Luca Zanin ◽  
...  

OBJECTIVEThe COVID-19 pandemic has forced many countries into lockdown and has led to the postponement of nonurgent neurosurgical procedures. Although stress has been investigated during this pandemic, there are no reports on anxiety in neurosurgical patients undergoing nonurgent surgical procedures.METHODSNeurosurgical patients admitted to hospitals in eastern Lombardy for nonurgent surgery after the lockdown prospectively completed a pre- and postoperative structured questionnaire. Recorded data included demographics, pathology, time on surgical waiting list, anxiety related to COVID-19, primary pathology and surgery, safety perception during hospital admission before and after surgery, and surgical outcomes. Anxiety was measured with the State-Trait Anxiety Inventory. Descriptive statistics were computed on the different variables and data were stratified according to pathology (oncological vs nononcological). Three different models were used to investigate which variables had the greatest impact on anxiety, oncological patients, and safety perception, respectively. Because the variables (Xs) were of a different nature (qualitative and quantitative), mostly asymmetrical, and related to outcome (Y) by nonlinear relationships, a machine learning approach composed of three steps (1, random forest growing; 2, relative variable importance measure; and 3, partial dependence plots) was chosen.RESULTSOne hundred twenty-three patients from 10 different hospitals were included in the study. None of the patients developed COVID-19 after surgery. State and trait anxiety were reported by 30.3% and 18.9% of patients, respectively. Higher values of state anxiety were documented in oncological compared to nononcological patients (46.7% vs 25%; p = 0.055). Anxiety was strongly associated with worry about primary pathology, surgery, disease worsening, and with stress during waiting time, as expected. Worry about positivity to SARS-CoV-2, however, was the strongest factor associated with anxiety, even though none of the patients were infected. Neuro-oncological disease was associated with state anxiety and with worry about surgery and COVID-19. Increased bed distance and availability of hand sanitizer were associated with a feeling of safety.CONCLUSIONSThese data underline the importance of psychological support, especially for neuro-oncological patients, during a pandemic.


Author(s):  
Abdullah Saadoon Salman ◽  
Nibras Mohammad Hadi ◽  
Aseel Jafer Jasem

The recognition of the content and its apparent and fundamental characteristics in the local architecture through the architectural knowledge to reach the architectural creativity with the variable output that fulfills the human, social and functional needs. The knowledge comes from the engines (theories and concepts) and their impact on the nature of the societies where they play a role in the conflict process Fixed values ​​to produce a content format. The recognition of the content and its apparent and fundamental characteristics in the local architecture through the architectural knowledge to reach the architectural creativity with the variable output that fulfills the human, social and functional needs. The knowledge comes from the engines (theories and concepts) and their impact on the nature of the societies where they play a role in the conflict process Fixed values ​​to produce a form with new content or adaptations to the constants to achieve creative communication rather than transport.  The dialectic between the fixed and the variable is a conflict in the production of ideas have been employed for the change of multiple dimensions and the role of architectural knowledge in the access to express the relative constant and relative variable to access the output to creativity and the role of the relationship between continuity and adaptation. New or adapted to the constants to achieve communication creativity and not transport.  The dialectic between the fixed and the variable is a conflict in the production of ideas have been employed for the change of m HGhghultiple dimensions and the role of architectural knowledge in the access to express the relative constant and relative variable to access the output to creativity and the role of the relationship between continuity and adaptation


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Galina Gramotnev ◽  
Dmitri K. Gramotnev ◽  
Alexandra Gramotnev

AbstractClinical and biochemical diversity of Parkinson’s disease (PD) presents a major challenge for accurate diagnosis and prediction of its progression. We propose, develop and optimize PD clinical scores as efficient integrated progression biomarkers for prediction of the likely rate of cognitive decline in PD patients. We considered 269 drug-naïve participants from the Parkinson’s Progression Marker Initiative database, diagnosed with idiopathic PD and observed between 4 and 6 years. Nineteen baseline clinical and pathological measures were systematically considered. Relative variable importance and logistic regressions were used to optimize combinations of significant baseline measures as integrated biomarkers. Parkinson’s disease cognitive decline scores were designed as new clinical biomarkers using optimally categorized baseline measures. Specificities and sensitivities of the biomarkers reached ~93% for prediction of severe rate of cognitive decline (with more than 5 points decline in 4 years on the Montreal Cognitive Assessment scale), and up to ~73% for mild-to-moderate decline (between 1 and 5 points decline). The developed biomarkers and clinical scores could resolve the long-standing clinical problem about reliable prediction of PD progression into cognitive deterioration. The outcomes also provide insights into the contributions of individual clinical and pathological measures to PD progression, and will assist with better-targeted treatment regiments, stratification of clinical trial and their evaluation.


2019 ◽  
Vol 59 (3) ◽  
pp. 347-359
Author(s):  
A. I. Akimov ◽  
E. S. Solomonova

The temperature rate growth dependence and the relative variable fluorescence, (Fv/Fm) of some of marine planktonic algae from the culture collections were investigated. The algae optima temperature growth (Topt), upper and lower limits tolerant zone of species, and in some cases, changes in the dynamics of these parameters outside the tolerance zone were determined. The similarity of species temperature characteristics with vegetation conditions these species in the nature was observed. Prolonged stress exposure to low positive temperature (4–6°C) was reversible; recovery of the growth rate and Fv/Fm was observed immediately after the increase of temperature. At temperatures above Topt on 2–3°C for diatoms was observed gradual degradation of culture, which, depending on the duration of exposure can lead to the death of the algae. Dinoflagellate species of the summer growing season had higher temperature resistance, and remained viable at temperatures above 5–8°C high Topt, due to lower growth rates. Rising part temperature dependence of the rate of growth approximated by a linear relation, the regression coefficient is 0.08–0.13 for diatoms and 0.03–0.11 for dinophyte. The normalized values for this parameter (the relative value of change in the growth rate, %) was 5.3±0.4 for diatoms and 6.4±0.5 for dinophyte at 1°C of temperature change. For dinophyte species were also been observed larger values of the parameter Q10. The value Fv/Fm for most species had high values in the whole temperature range, in which maintained a stable growth of algae. The fall of this parameter was observed in increasing the border of tolerance zone, and was associated with inhibition of thermal growth processes.


2018 ◽  
Vol 45 (6) ◽  
pp. 668 ◽  
Author(s):  
Izabela A. Samborska ◽  
Hazem M. Kalaji ◽  
Leszek Sieczko ◽  
Vasilij Goltsev ◽  
Wojciech Borucki ◽  
...  

Magnesium (Mg) is one of the significant macronutrients which is involved in the structural stabilisation of plant tissues and many enzymes such as PSII. The latter efficiency and performance were analysed, using chlorophyll (Chl) a fluorescence induction kinetics and microscopic images, to detect the changes in structure and function of photosynthetic apparatus of radish plants grown under Mg deficiency (Mgdef). Plants grown under Mgdef showed less PSII connectivity and fewer active primary electron acceptors (QA) oxidizing reaction centres than control plants. Confocal and electron microscopy analyses showed an increased amount of starch in chloroplasts, and 3,3ʹ-diaminobenzidine (DAB)-uptake method revealed higher H2O2 accumulation under Mgdef. Prominent changes in the Chl a fluorescence parameters such as dissipated energy flux per reaction centre (DIo/RC), relative variable fluorescence at 150 μs (Vl), and the sum of the partial driving forces for the events involved in OJIP fluorescence rise (DFabs) were observed under Mg deficiency. The latter also significantly affected some other parameters such as dissipated energy fluxes per cross-section (DIo/CSo), performance index for energy conservation from photons absorbed by PSII antenna until the reduction of PSI acceptors (PItotal), and relative variable fluorescence at 300 μs (Vk). This work emphasises the use of chlorophyll fluorescence in combination with microscopic and statistical analyses to diagnose the effects of nutrients deficiency stress on plants at an early stage of its development as demonstrated for the example of Mgdef. Due to the short growth period and simple cultivation conditions of radish plant we recommend it as a new standard (model) plant to study nutrients deficiency and changes in plant photosynthetic efficiency under stress conditions.


2017 ◽  
Vol 60 (2) ◽  
pp. 145-151 ◽  
Author(s):  
Andrzej Kowalski ◽  
Sebastian Knaga

Abstract. The goal of this work was to check whether selection for quantitative traits may cause a change in the histone H1 allelic complement and whether it can therefore be considered a modulator of histone H1-dependent chromatin functioning. For this purpose, a fluctuation of histone H1.a polymorphic variants was analyzed among a non-selected (control) quail line and the line selected for a high cholesterol content in the egg yolk. The histone H1.a was found to be polymorphic due to its differential migration rate in the AU-PAGE (acetic acid–urea polyacrylamide gel electrophoresis). Based on this, two H1.a isoforms (H1.a1 and H1.a2) that form three phenotypes (a1, a2 and a1a2) were distinguished in the quail lines tested. A comparably expressed (p > 0. 05) and low relative variable (coefficient of variation, CV  < 0. 25) histone H1.a phenotypes were in agreement with Hardy–Weinberg equilibrium (HWE) in both the non-selected (χ2 = 1. 29, p = 0. 25) and selected (χ2 = 1. 9, p = 0. 16) quail line. The similarity among quail lines was assessed based on the equal distribution of histone H1.a phenotypes (χ2 = 1. 63, p = 0. 44) and alleles (χ2 = 0. 018, p = 0. 89) frequency in both quail lines tested. This indicates that selection does not affect the histone H1.a polymorphic variants. The stability of histone H1.a during selection might suggest that likely chromatin processes coupled to the selected trait are not linked to the activity of histone H1.a.


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