scholarly journals Effect of abiotic stress factors on polyphenolic content in the skin and flesh of pear by UPLC-PDA-Q/TOF-MS

2019 ◽  
Vol 245 (12) ◽  
pp. 2715-2725 ◽  
Author(s):  
Tomasz Cebulak ◽  
Jan Oszmiański ◽  
Ireneusz Kapusta ◽  
Sabina Lachowicz
Keyword(s):  
High Frequency ◽  
Control Sample ◽  
Low Frequency ◽  
Polyphenolic Compounds ◽  
Stress Factors ◽  
Biological Quality ◽  
Abiotic Stress Factors ◽  
Quality Of Food ◽  
Uvc Radiation

Abstract Growing social interest in foods with high biological quality results in the need to look for possibilities of increasing the biological quality of food products. The aim of this research was an attempt to estimate the increase of polyphenolic compounds (by UPLC-PDA-MS/MS) in the flesh and skin of pear under the influence of stress elicitors such as UVC radiation, L-EMF, H-EMF and US with various exposure times. The applied stress factors differentiated the content of phenolic acids, flavan-3-ols and flavonols both in flesh and in skin. In all cases, pear skin demonstrated a decrease in the sum of polyphenolic compounds; however, when it comes to flavan-3-ols and procyanidins, the concentration of the compounds increased in two cases: after a 30-min exposure to L-EMF (+ 18%) and after a 5-min exposure to H-EMF (+ 20%). Following a 30-min flesh exposure to US, the determined sum of polyphenolic compounds was + 28% higher than in the control sample. It was observed that the level of flavan-3-ols and procyanidins in the flesh increased after a 60-min exposure to UVC radiation and low-frequency and high-frequency electromagnetic fields, and after a 20-min and 30-min exposure to ultrasounds. The presence of flavonols was only observed in pear skin. The research results show that it is possible to produce juice with a higher content of polyphenolic compounds, because juice is obtained mainly from the flesh; however, there is a need for further research to confirm the observed tendencies in the changes of polyphenolic compounds in fractions of pears.

Dynamics of the processes in metal machining

1998 ◽  
Vol 2 ◽  
pp. 115-122
Author(s):  
Donatas Švitra ◽  
Jolanta Janutėnienė
Keyword(s):  
High Frequency ◽  
Machine Tools ◽  
Metal Cutting ◽  
Cutting Tool ◽  
Low Frequency ◽  
Metal Cutting Machine ◽  
Cutting Machine ◽  
Metal Machining

In the practice of processing of metals by cutting it is necessary to overcome the vibration of the cutting tool, the processed detail and units of the machine tool. These vibrations in many cases are an obstacle to increase the productivity and quality of treatment of details on metal-cutting machine tools. Vibration at cutting of metals is a very diverse phenomenon due to both it’s nature and the form of oscillatory motion. The most general classification of vibrations at cutting is a division them into forced vibration and autovibrations. The most difficult to remove and poorly investigated are the autovibrations, i.e. vibrations arising at the absence of external periodic forces. The autovibrations, stipulated by the process of cutting on metalcutting machine are of two types: the low-frequency autovibrations and high-frequency autovibrations. When the low-frequency autovibration there appear, the cutting process ought to be terminated and the cause of the vibrations eliminated. Otherwise, there is a danger of a break of both machine and tool. In the case of high-frequency vibration the machine operates apparently quiently, but the processed surface feature small-sized roughness. The frequency of autovibrations can reach 5000 Hz and more.

scholarly journals Influence of Abiotic Stress Factors on the Antioxidant Properties and Polyphenols Profile Composition of Green Barley (Hordeum vulgare L.)

2020 ◽  
Vol 21 (2) ◽  
pp. 397 ◽  
Author(s):  
Przemysław Łukasz Kowalczewski ◽  
Dominika Radzikowska ◽  
Eva Ivanišová ◽  
Artur Szwengiel ◽  
Miroslava Kačániová ◽  
...  
Keyword(s):  
Antioxidant Properties ◽  
Water Shortage ◽  
Co2 Assimilation ◽  
Polyphenolic Compounds ◽  
Stress Factors ◽  
Physiological Status ◽  
Simple Relationship ◽  
Hordeum Vulgare L ◽  
Abiotic Stress Factors ◽  
The Impact

The influence of stress factors on the plant can, on the one hand, lead to worse functioning of the plant and loss of its crop, but on the other, it can have a positive effect on the metabolism of compounds with documented biological activity. In this study, the effect of light and drought intensity on photosynthetic activity and physiological status of two barley varieties, as well as the antimicrobial, antioxidant properties and profile of polyphenolic compounds of green barley were analysed. It was shown that under the conditions of water shortage, the KWS Olof variety showed a smaller decrease in CO2 assimilation and transpiration and higher values of these parameters at both light intensities. Only in the KWS Olof variety increased stress as a result of increased light intensity. It has also been shown that both the intensity of radiation and drought-related stress have a significant impact on the profile of polyphenolic compounds from green barley, without a simple relationship between the impact of stress factors on the content of polyphenols. Changes in the profile of polyphenolic compounds augmented the antioxidant and antimicrobial activity of the material. This, in turn, proposes the possibility of reducing the applied doses of herbal material thanks to a greater content of active substances in extracts obtained from the plants used to produce medicinal preparations.

Mind–body interactive qigong improves physical and mental aspects of quality of life in inpatients with stroke: A randomized control study

2019 ◽  
Vol 18 (8) ◽  
pp. 658-666 ◽  
Author(s):  
Ching-Hsiang Chen ◽  
Kuo-Sheng Hung ◽  
Yu-Chu Chung ◽  
Mei-Ling Yeh
Keyword(s):  
Quality Of Life ◽  
Heart Rate ◽  
Heart Rate Variability ◽  
High Frequency ◽  
Standard Care ◽  
Low Frequency ◽  
Control Group ◽  
Subacute Stroke ◽  
Interactive Exercise

Background: Stroke, a medical condition that causes physical disability and mental health problems, impacts negatively on quality of life. Post-stroke rehabilitation is critical to restoring quality of life in these patients. Objectives: This study was designed to evaluate the effect of a mind–body interactive qigong intervention on the physical and mental aspects of quality of life, considering bio-physiological and mental covariates in subacute stroke inpatients. Methods: A randomized controlled trial with repeated measures design was used. A total of 68 participants were recruited from the medical and rehabilitation wards at a teaching hospital in northern Taiwan and then randomly assigned either to the Chan-Chuang qigong group, which received standard care plus a 10-day mind–body interactive exercise program, or to the control group, which received standard care only. Data were collected using the National Institutes of Health Stroke Scale, Hospital Anxiety and Depression Scale, Short Form-12, stroke-related neurologic deficit, muscular strength, heart rate variability and fatigue at three time points: pre-intervention, halfway through the intervention (day 5) and on the final day of the intervention (day 10). Results: The results of the mixed-effect model analysis showed that the qigong group had a significantly higher quality of life score at day 10 ( p<0.05) than the control group. Among the covariates, neurologic deficit ( p=0.04), muscle strength ( p=0.04), low frequency to high frequency ratio ( p=0.02) and anxiety ( p=0.04) were significantly associated with changes in quality of life. Conversely, heart rate, heart rate variability (standard deviation of normal-to-normal intervals, low frequency and high frequency), fatigue and depression were not significantly associated with change in quality of life ( p >0.05). Conclusions: This study supports the potential benefits of a 10-day mind–body interactive exercise (Chan-Chuang qigong) program for subacute stroke inpatients and provides information that may be useful in planning adjunctive rehabilitative care for stroke inpatients.

scholarly journals Effect of Closed-Loop Vibration Stimulation on Heart Rhythm during Naps

Sensors ◽  
2019 ◽  
Vol 19 (19) ◽  
pp. 4136 ◽  
Author(s):  
Sang Ho Choi ◽  
Heenam Yoon ◽  
Hyung Won Jin ◽  
Hyun Bin Kwon ◽  
Seong Min Oh ◽  
...  
Keyword(s):  
High Frequency ◽  
Closed Loop ◽  
Low Frequency ◽  
Heart Rhythm ◽  
Quality Of Sleep ◽  
Stimulation Condition ◽  
Term Basis ◽  
Stimulation System

Sleep plays a primary function for health and sustains physical and cognitive performance. Although various stimulation systems for enhancing sleep have been developed, they are difficult to use on a long-term basis. This paper proposes a novel stimulation system and confirms its feasibility for sleep. Specifically, in this study, a closed-loop vibration stimulation system that detects the heart rate (HR) and applies −n% stimulus beats per minute (BPM) computed on the basis of the previous 5 min of HR data was developed. Ten subjects participated in the evaluation experiment, in which they took a nap for approximately 90 min. The experiment comprised one baseline and three stimulation conditions. HR variability analysis showed that the normalized low frequency (LF) and LF/high frequency (HF) parameters significantly decreased compared to the baseline condition, while the normalized HF parameter significantly increased under the −3% stimulation condition. In addition, the HR density around the stimulus BPM significantly increased under the −3% stimulation condition. The results confirm that the proposed stimulation system could influence heart rhythm and stabilize the autonomic nervous system. This study thus provides a new stimulation approach to enhance the quality of sleep and has the potential for enhancing health levels through sleep manipulation.

scholarly journals Characteristics and Influence to Fruit Distillates Quality of Rapid Induction of Ageing Character in the Presence of Mulberry Tree (Morus alba L.) Wooden Chips

2016 ◽  
Vol 73 (2) ◽  
pp. 165
Author(s):  
Elena MUDURA ◽  
Teodora COLDEA ◽  
Timea HORVATH ◽  
Carmen Rodica POP
Keyword(s):  
Heat Treatment ◽  
Chemical Composition ◽  
Volatile Compounds ◽  
Control Sample ◽  
Polyphenolic Compounds ◽  
Chemical Parameters ◽  
Rapid Induction ◽  
Factors Influencing ◽  
Mulberry Tree

Research on rapid induction of ageing character to double distilled traditional fruit brandies, from Transylvania region was conducted. Mulberry tree chips were used as an alternative to traditional ageing in wooden barrels. The aim of this study was to highlight the factors influencing the chemical composition of fruit brandies, both depending on the type of the wood used and the transformations occurred during the heat treatment. Fruit distillates were produced after the traditional method – double distillation in copper alambic. The evaluation of the brandies consisted in analyzing the chemical parameters and the phenolic compounds after two months of ageing with wood chips. Results were compared with a control sample (unaged distillate), and found that during the ageing process volatile and non-volatile compounds were extracted significantly. The heat treatment influenced the chemical composition of the wooden chips. The chemical composition of finished products varied due to the composition of the wooden chips used and to the heat treatment applied. Evaluation of volatile and non-volatile compounds formed was carried out by comparison with the samples of the unaged distillate. It was demonstrated the improvement of chemical characteristics and polyphenolic compounds content, by rapidly inducing of the ageing character.

scholarly journals Pansharpening with a Gradient Domain GIF Based on NSST

Electronics ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 229
Author(s):  
Jiao Jiao ◽  
Lingda Wu
Keyword(s):  
High Frequency ◽  
Low Frequency ◽  
Fusion Rule ◽  
Objective Evaluation ◽  
Data Sets ◽  
Multi Scale ◽  
Guided Image Filter ◽  
Gradient Domain ◽  
Spatial Quality

In order to improve the fusion quality of multispectral (MS) and panchromatic (PAN) images, a pansharpening method with a gradient domain guided image filter (GIF) that is based on non-subsampled shearlet transform (NSST) is proposed. First, multi-scale decomposition of MS and PAN images is performed by NSST. Second, different fusion rules are designed for high- and low-frequency coefficients. A fusion rule that is based on morphological filter-based intensity modulation (MFIM) technology is proposed for the low-frequency coefficients, and the edge refinement is carried out based on a gradient domain GIF to obtain the fused low-frequency coefficients. For the high-frequency coefficients, a fusion rule based on an improved pulse coupled neural network (PCNN) is adopted. The gradient domain GIF optimizes the firing map of the PCNN model, and then the fusion decision map is calculated to guide the fusion of the high-frequency coefficients. Finally, the fused high- and low-frequency coefficients are reconstructed with inverse NSST to obtain the fusion image. The proposed method was tested using the WorldView-2 and QuickBird data sets; the subjective visual effects and objective evaluation demonstrate that the proposed method is superior to the state-of-the-art pansharpening methods, and it can efficiently improve the spatial quality and spectral maintenance.

scholarly journals Single note dissonance through harmonic self-interference

2016 ◽  
Vol 9 (1) ◽  
Author(s):  
Maxwell Ng
Keyword(s):  
High Frequency ◽  
Low Frequency ◽  
The Future ◽  
Qualitative Effect

In music, dissonance is the unpleasant quality of sound. While dissonance is generally regarded as arising from two notes played simultaneously, low frequency notes sound dissonant when played alone on a piano. I hypothesize that this dissonance arises from the harmonics of the played note interfering with one another. Using the piano as a model, perceived dissonance was calculated through the combination of the two-tone dissonance formula with the A-weighting curve and the different harmonic intensities of a piano. Spectrographs of sample piano notes were used to compare harmonics of low frequency and high frequency notes.Single note dissonance increased rapidly as note frequency decreased. A-weighting had no qualitative effect on the dissonance-frequency trend, implying a physical and not a psychoacoustic cause. As verified in the spectrographs, the lower register note had harmonics closer together, compared to the higher register note. It is thus possible that the harmonics of low notes interfere significantly with each other, thereby producing the observed single-note dissonance.The simulation produces a score for the perceived dissonance of a single-note played on the piano. This analysis could be adapted in the future to other instruments, including aerophones, as well as integrate timbre, partials, and inharmonics. La dissonance musicale et pour la plupart compris en matière de deux notes simultanées. Cependant, les notes de basse fréquence semble en désordre quand ils sont joués seules sur un piano. L’explication proposée dans cet oeuvre est que cette dissonance se produit des harmoniques des notes qui s’interfèrent. Utilisant le piano comme exemple, la dissonance perçue a été calculé par la combination de la formule de dissonance entre deux notes avec la courbe de pondération A et les intensités harmoniques d’un piano. Les spectres sonores des notes de piano ont été utilisés pour la comparaison des notes de basse et haut fréquences. La dissonance des seules notes augmentait rapidement alors que les fréquences des notes diminuaient. La pondération A n’avait pas eu un effet sur la tendance entre la dissonance et les fréquences, qui signifie la présence d’une cause physique au lieu d’une cause auditive. Vérifié dans les spectres sonores, la note de registre inférieur avait ses harmoniques plus proches comparés à la note du registre plus haut. C’est alors possible que les harmoniques des notes des registres inférieurs interfèrent considérablement avec les unes les autres, et produit ainsi la dissonance des seules notes observée dans les calculs. La simulation produit un résultat pour la dissonance perçue sur un piano. Cette analyse pourrait être adaptée dans le futur aux autres instruments, incluant les aérophones, et puis intégrer aussi des analyses de timbre, des tons simples, et des inharmoniques.

scholarly journals Comparison of Low and High Frequency Partial Discharge Measurements on Stator Windings

2019 ◽  
pp. 134-138
Author(s):  
Greg C Stone ◽  
Howard Sedding
Keyword(s):  
High Frequency ◽  
Partial Discharge ◽  
Low Frequency ◽  
International Standards ◽  
Very High Frequency ◽  
Stator Windings ◽  
Advantages And Disadvantages ◽  
On Line ◽  
Winding Insulation

Partial discharge (PD) testing has been used for over 60 years primarily as a method to assess condition of the stator winding insulation in motors and generators rated 6 kV and above. More recently it has also been used by some machine manufacturers as a means of assuring the quality of the insulation on single winding elements (coils and bars). Although both on-line and off-line tests mainly use a high voltage capacitor to detect the PD, the PD measuring systems in use work either in the low frequency (LF) regime (less than about 1 MHz) or in the very high frequency (VHF) (30-300 MHz) range. By reference to several international standards, published work as well as some experiments described in this contribution, the advantages and disadvantages of the two approaches are compared. Based on this work, it is now clear that off-line PD tests should be done in the LF range. For on-line tests, either method may be used, but use of the VHF method has become more widespread with machine end users, since the owners themselves can perform and interpret the results with a relatively low risk of false indications.

scholarly journals Antiforensics of Speech Resampling Using Dual-Path Strategy

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Diqun Yan ◽  
Yongkang Gong ◽  
Tianyun Liu
Keyword(s):  
High Frequency ◽  
Gaussian White Noise ◽  
Sampling Rate ◽  
Low Frequency ◽  
Frequency Component ◽  
High Frequency Component ◽  
Perceptual Quality ◽  
Median Filtering ◽  
Noise Perturbation

Resampling is an operation to convert a digital speech from a given sampling rate to a different one. It can be used to interface two systems with different sampling rates. Unfortunately, resampling may also be intentionally utilized as a postoperation to remove the manipulated artifacts left by pitch shifting, splicing, etc. To detect the resampling, some forensic detectors have been proposed. Little consideration, however, has been given to the security of these detectors themselves. To expose weaknesses of these resampling detectors and hide the resampling artifacts, a dual-path resampling antiforensic framework is proposed in this paper. In the proposed framework, 1D median filtering is utilized to destroy the linear correlation between the adjacent speech samples introduced by resampling on low-frequency component. And for high-frequency component, Gaussian white noise perturbation (GWNP) is adopted to destroy the periodic resampling traces. The experimental results show that the proposed method successfully deceives the existing resampling forensic algorithms while keeping good perceptual quality of the resampled speech.

DEVELOPMENT OF PHYSICAL AND BIOLOGICAL METHODS OF PROTECTION  TO IMPROVE PRESERVATION AND QUALITY OF APPLES

2019 ◽  
Author(s):  
М.Д. НАЗАРЬКО ◽  
В.Г. ЛОБАНОВ ◽  
Г.И. КАСЬЯНОВ ◽  
С.В. УСАТИКОВ ◽  
Е.В. ИНОЧКИНА ◽  
...  
Keyword(s):  
Control Sample ◽  
Low Frequency ◽  
Processing Parameters ◽  
Toxicological Effects ◽  
Optimal Processing ◽  
Number Of Microorganisms ◽  
Additional Processing ◽  
Processing Control ◽  
Biological Methods

Предложен комплекс мер по оптимизации биотехнологических приемов, гарантирующих сохранность и качество яблочной продукции без токсикологического воздействия на плоды и их потребителя. Яблоки сорта Айдаред из экологически чистого сада перед закладкой на хранение подвергали обработке биопрепаратом с адъювантом и воздействию электромагнитным полем крайне низкой частоты (ЭМП КНЧ). Для сравнения на хранение были заложены яблоки, выращенные без использования химических препаратов, и при закладке на хранение их не подвергали дополнительной обработке (контрольный образец). Подобраны оптимальные параметры обработки ЭМП КНЧ: частота модулирующих колебаний 38 Гц, продолжительность обработки 1420 мин. В процессе хранения были исследованы микробиологические и химикотехнологические показатели яблок. Установлено, что начальные показатели количества микрофлоры у яблок, выращенных без использования химических препаратов, (контроль) выше, чем аналогичные показатели яблок, выращенных с использованием биопрепаратов и обработанных биопрепаратом и ЭМП КНЧ в момент закладки на хранение. В процессе хранения не обработанных ЭМП КНЧ яблок количество микроорганизмов увеличилось в 5 6 раз, особенно микромицетов. Через 4 мес. количество пораженных плодов составило более 40. После обработки яблок биопрепаратом и ЭМП КНЧ наблюдалось снижение численности бактерий и микромицетов, а через 3 мес. хранения их количество вновь увеличилось. В процессе хранения в плодах яблок, обработанных биопрепаратом и ЭМП КНЧ, наблюдалось постепенное снижение содержания витамина С и убыль по массе. Однако эти показатели значительно ниже аналогичных в контрольном образце. The complex of measures on optimization of biotechnological methods guaranteeing the preservation of yield and quality of apple products no toxicological effects on the fruits and they consumer offered. Apples Aydared from the organic garden before laying on the storage exposed treated biopreparation with adjuvant and extremely low frequency electromagnetic field (EMF ELF). For comparison, apples grown without the use of chemicals were laid for storage, and when they were laid for storage, they were not subjected to additional processing (control sample). Optimal processing parameters of the EMF ELF are selected: frequency of the modulating oscillations 38 Hz, the processing time of 1420 min. Microbiological and chemicaltechnological parameters of apples were investigated during storage. It was found that the initial indicators of the amount of microflora in apples grown without the use of chemicals (control) is higher than similar indicators of apples grown using biological products and treated with a biopreparation and EMF ELF at the time of storage. In the process of storage of untreated EMF ELF apples the number of microorganisms increased by 5 6 times, especially micromycetes. After 4 months the number of affected fruits was more than 40. After the treatment of apples with biopreparation and EMF ELF a decrease in the number of bacteria and micromycetes was observed, and after 3 months storage their number has increased again. During storage in the apples treated with biopreparation and EMF ELF, a gradual decrease in the content of vitamin C and a decrease in weight ware observed. However these figures are significantly lower than those in the control sample.

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