VARIABILITY OF SOME BROOMRAPE POPULATIONS FROM CHINA. MORPHOMETRY AND RACE IDENTIFICATION (I)

The article is a synthesis of some studies on the identification of broomrape races originating from China and the determination of the level of intra- and interpopulation variability based on the morphometric parameters of the seeds. The racial status of the analyzed populations was established, also two races of broomrape were identified: race G (Ch1 from Inner Mongolia and Ch3 from HeBei) and race H (Ch2 from Inner Mongolia) using internationally recognized differential Or homosygous lines set. Comparative analyses on the morphometric characteristics of broomrape revealed significant differences in seed Length (Ch1 and Ch3 populations, race G) and Length/width ratio (Ch3 and Ch4), which is an indication of the moderate level of interpopulation variability. In the case of assess of the intrapopulation variability level, the relatively homogeneous (Ch2, Ch3 and Ch4) and relatively heterogeneous (Ch1) populations were identified. According to the coefficient of variation, the population Ch2 identified as H broomrape race has distinguished as the most homogeneous for the investigated biometric indices of the seeds. The moderate positive correlations (between Length and width seed, between seed length and L/w ratio), the strong positive correlations (between Length and L/w ratio) and also the strong negative correlations (between width and L/w ratio) were established. The results obtained through Pearson coefficient revealed the discrimination of populations by region.

Formation of the oil flax yield in the conditions of the Sverdlovsk region

Oil flax was grown on gray forest soils of the Middle Urals in the period 2012-2020. The purpose of the research was to identify changes in the yield structure of various oil flax varieties and its productivity, depending on the growing conditions. The research used the method of field experience and statistical processing of experimental data. It was found that the conditions of the year of growing oil flax had a noticeable effect on the number of formed capsules on the plant, seeds in one capsule and the mass of 1000 seeds. Small seeds of all varieties were formed in the conditions of warm and dry 2012, and the largest seeds were obtained in cool and wet 2015. The average yield of oil flax seeds was 1.90-2.14 t/ha, the maximum yield was 2.88 t/ha, provided by the Ural variety in 2017. The yield variability level by 77.7 % was determined by environmental conditions, the influence of genotypes caused 6.6% of yield variation, and the interaction of genotype x environment - 14.9 %.

Moderate movement variability is optimal in massive practiced dart throws

Background and Study Aim. Movement variability is one of the fundamental topics concerning the control of human movement. In recent years, researches have focused on various aspects of variability, which has changed the noise to useful variable on human movement. Present study investigated movement variability level in high skilled dart players that repeated throws over many years. Material and Methods. Seven experienced dart players (three women and four men) were threw 36 darts in three sets (each set 12 throws) from a standard distance (2.37 meters), while the kinematic features of the shoulder, elbow, and wrist were recorded during the throws. Qualisys motion capture system with six cameras was used to record the kinematics of the elbow. Results: entropy analysis revealed that greater variability in movement angle, velocity and acceleration resulted in better dart throwing performance but after reach to this level, throw variability was decreased. The remarkable point in these findings was that variability was constant across all samples despite the varied range of experience in throwing darts from 2.37 meters distance. Entropy analysis showed that in the throws of highly experienced individuals, variation led to greater throwing efficiency. Conclusions: these findings suggest that variability in a throwing activity, which revealed that moderate movement variability results in optimal throwing performance when dart throw has massive amount of practice during many years.

The Effect of Between-Probe Variability in Haptic Feedback on Stiffness Perception and Grip Force Adjustment

When interacting with objects, haptic information is used to create perception of the object stiffness and to regulate grip force. Studies have shown that introducing noise into sensory inputs can create uncertainty in those sensory channels, yet a method of creating haptic uncertainty without distorting the haptic information has yet to be discovered. Toward this end, we investigated the effect of between-probe haptic variability on stiffness perception and grip force control. In a stiffness discrimination task, we added different levels of between-probe haptic variability by changing the stiffness of the force fields between consecutive probes. Unlike the low and high variability levels, the medium level created perceptual haptic uncertainty. Additionally, we ascertained that participants calculated a weighted average of the different stiffness levels applied by a given force field. Examining participants’ grip force showed that the modulation of the grip force with the load force decreased with repeated exposure to the force field, whereas no change in the baseline was observed. These results were observed in all the variability levels and suggest that between-probe variability created haptic uncertainty that affected the grip force control. Overall, the medium variability level can be effective in inducing uncertainty in both perception and action.

Morphological variability of Quercus robur L. plus trees and clones in Podillia

The results of the study of English oak (Quercus robur L.) plus trees based on the morphological features of their leaves, acorns, and peduncles are presented. Samples were collected from both plus trees in forest stands and clones in clonal archive of English oak in Vinnytsia Region. In total, 41 trees were analyzed by 7 features of their leaves and 30 of those trees – by 9 morphological features of their acorns and peduncles. A point assessment was used for nonmetric indicators. To compare plus trees by morphological features, the graphical method of morphotypes image representation with the usage of radar charts is suggested. Given that absolute indicators may depend on the year’s weather conditions, only relative indicators assessed in points were used to plot charts. The average indices for the trees as well as the variability level between them are determined. The most variable features were identified and offered to use for clone identification. It has been suggested that 8 plus trees whose leaves’ base is rounded are the hybrids of English and sessile oaks. It is confirmed that all the studied plus trees of Vinnytsia origin differed in one or several morphological features of their leaves, acorns, or peduncles. However, two plus trees of Odesa origin were similar in their leaves’ characteristics and two clones of Vinnytsia origin were similar in their acorns and peduncles’ features. It is noted that the use of morphological indicators of leaves and reproductive organs, taken as a whole, allows obtaining a rather complete description of a plus tree or its clone, and the usage of the graphical method allows determining the difference and similarity of individuals and their groups. Graphic images of morphotypes given as radar charts can be used to compare individuals, their groups, populations, variants in both progeny test and provenance trial, so to identify clones in clonal seed orchards.

Galaxy optical variability of Virgo cluster: new tracer for environmental influences on galaxies

ABSTRACT We investigate the relationship between the optical variability of galaxies and their distances from the centre of the Virgo cluster using Palomar Transient Factory data. We define the ratio between the standard deviation of the galaxy brightness and the mean value of the standard deviation as a measure of a galaxy’s optical variability. A sample of 814 Virgo galaxies with 230 263 observations shows a monotonically decreasing trend of optical variability with increasing clustercentric distance. The variability level inside the cluster is 3.2σ higher than the level outside. We fit the variability with a linear function and find that the data reject a distance-independent model. We examine 217 background galaxies for comparison and find no significant trend in galaxy variability. We assess the relation with Monte Carlo simulation by rebuilding the brightness of each galaxy. The simulation shows a monotonically decreasing relation for member galaxy variability and a distance-independent relation for background galaxies. Our result is consistent with the theory that the cold gas flowing inwards the cluster centre fuels AGN activity. This work is a new implementation of the method using optical variability to investigate the relation between galaxies evolution and their environment.

Assessment of time of emergence of anthropogenic deoxygenation and warming: insights from a CESM simulation from 850 to 2100 CE

Marine deoxygenation and anthropogenic ocean warming are observed and projected to intensify in the future. These changes potentially impact the functions and services of marine ecosystems. A key question is whether marine ecosystems are already or will soon be exposed to environmental conditions not experienced during the last millennium. Using a forced simulation with the Community Earth System Model (CESM) over the period 850 to 2100, we find that anthropogenic deoxygenation and warming in the thermocline exceeded natural variability in, respectively, 60 % and 90 % of total ocean area. Control simulations are typically used to estimate the pre-industrial variability level. However, the natural variability of oxygen (O2) and temperature (T) inferred from the last millennium period is systematically larger than the internal variability simulated in the corresponding control simulation. This renders natural variability from control simulations to be biased towards low estimates. Here, natural variability is assessed from the last millennium period (850–1800 CE), thus considering the response to forcing from explosive volcanic eruptions, solar irradiance and greenhouse gases in addition to internal, chaotic variability. Results suggest that in the tropical thermocline, where biological and solubility-driven O2 changes counteract each other, anthropogenic changes in apparent oxygen utilisation (AOU) and in O2 solubility (O2,sol) are detectable earlier than O2 changes. Both natural variability and change in AOU are predominantly driven by variations in circulation with a smaller role for productivity. By the end of the 21st century, ventilation becomes more vigorous in the tropical thermocline, whereas ideal age in deep waters increases by more than 200 years relative to the pre-industrial period. Different methodological choices are compared and the time for an anthropogenic signal to emerge (ToE) is earlier in many thermocline regions when using variability from a shorter period, from the control simulation or estimates from the industrial period instead of the variability from the last millennium. Our results highlight that published methods may lead to deviations in ToE estimates, calling for a careful quantification of variability. They also highlight that realised anthropogenic change exceeds natural variations in many regions.

Study Regarding the Elastic Impression Biomaterials Dimensional Stability

In order to have an accurate impression, dimensional modifications must be under control throughout the impression stages, considering they are highly influenced by the variability level during polymerization.The factors with an influence on dimensional stability are:impression material width, tensile modulus, temperature during the imprinting process, storage humidity, the time lapse between imprinting and casting. The study focuses on dimensional modifications of varied elastic impression materials, considering both testing and impression techniques are done in similar conditions in order to assess accurately the behaviour of varied impression materials.Material and methods:The study was based on a laboratory simulation of a clinical situation. There were used two 6-year maxillary molars in the position they have in the oral cavity. A 3 mm wax layer was added during the next stage its width being checked with an Ivoclar mechanical vernier. The surface parallelism was subsequently checked using a parallelograph and there was taken an individual tray made of photopolymer acrylic. The measurements of this study were limited to the linear dimension, being observed the changes occurred in one direction, although contraction is a volumetric modification.The statistic assessment of the measurement data obtained in the case of the same type of addition silicon materials recorded an increase of the volumetric contraction type in dry environment and in longer time intervals.The addition materials were significantly superior in terms of contraction time, as compared to the previous case, granting higher accuracy to the end product. The Silagum Light presented an increased volumetric contraction in moist environment, the contraction being more significant in longer time intervals. The Xantopren L blue material has a reduced deformation gradient in less than 48 h.

Мінливість господарсько-цінних ознак сої в умовах Лівобережного Лісостепу України

Мета статті – встановлення рівня мінливості господарсько-цінних ознак у генотипів сої в умовах Лівобережного Лісостепу України. Для результативності роботи, спрямованої на створення високопродуктивних сортів, необхідно удосконалювати методи селекції. При цьому важливе значення має встановлення рівня мінливості у сортів та сортозразків сої. Методика дослідження. Для наукового обґрунтування мети і реалізації встановлених завдань та узагальнення результатів дослідження застосовували наступні методи: загальнонаукові (визначення напряму дослідження, планування і закладка досліду, проведення спостережень); спеціальні (польовий ‒ для спостереження за фенологічними фазами розвитку та станом рослин; лабораторний (вимірювально-ваговий) ‒ для визначення структурних показників та продуктивності рослин, виявлення господарсько цінних ознак рослин); математично-статистичний (для обробки експериментальних даних, визначення параметрів мінливості ознак і визначення достовірності одержаних результатів). Результати дослідження. У статті наведено результати досліджень з вивчення мінливості господарсько-цінних ознак у сої в умовах Лівобережного Лісостепу України. З’ясовано, що високий рівень мінливості мають ознаки «маса насіння з рослини» (V=22,8%) і «кількість бобів на рослині» (V=22,9%). Середнім рівнем мінливості характеризувалися ознаки «кількість насіння з рослини» (V=16,4,%), «маса 1000 насінин» (V=11,1%), «висота рослини» (V=13,4%), «висота прикріплення нижнього бобу» (V=17,1%). Елементи наукової новизни. Доведено, що на основі детального вивчення мінливості кількісних ознак у генотипів сої можливо ефективно проводити селекційну роботу зі створення високопродуктивних сортів. У селекційному процесі необхідно орієнтуватися на стабільні показники кількісних ознак. У наших дослідженнях це «кількість насіння з рослини», «маса 1000 насінин», «висота рослини», «висота прикріплення нижнього бобу». Практична значущість. Вивчення мінливості господарсько-цінних ознак сої забезпечує результативне ведення селекції. The aim of the article is to establish the variability level of economically-valuable characteristics of soybean genotypes under the conditions of the Left-Bank Forest-Steppe of Ukraine. It is necessary to improve the selection methods for the efficient work, aimed at creating highly-productive varieties. Moreover, it is important to establish the variability level of soybean varieties and variety samples. Methods of the research. The following methods were used to substantiate scientifically the purpose, implement the established tasks and summarize the research results: general-scientific (studying the direction of the research, planning and carrying out the experiment; conducting observations); special (field – to observe phenological development stages and the condition of plants; laboratory (measuring-weighing) – to determine structural indices and plant productivity, to detect economically-valuable plant signs); mathematical-statistical (to process experimental data, determine the parameters of variability signs and define the significance of the obtained results). The research results. The research results of studying the variability of economically-valuable characteristics of soybean under the conditions of the Left-Bank Forest-Steppe of Ukraine have been given in the article. It has been established that the following characteristics have a high level of variability: the seed weight per plant (V=22.8%) and the number of pods on a plant (V=22.9%). Such characteristics as the number of seeds per plant (V=16.4%), the weight of 1000 seeds (V=11.1%), plant height (V=13.4%), and also the height of the lower pod attachment (V=17.1%) are characterized by the average level of variability. The elements of scientific novelty. It has been proved that based on the detailed studying the quantitative signs’ variability of soybean genotypes, it is possible to conduct effectively the selection work in creating highly productive varieties. In the selection process one should be oriented at stable indices of quantitative signs. In our research these are: the number of seeds per plant, the weight of 1000 seeds, plant height, and the height of the lower pod attachment. Practical importance. Studying the variability of economically-valuable characteristics of soybean ensures the effective selection.

Strategies for Improving V-KOSPI 200 Index

The study examines not only the methods for eliminating stale or abnormal prices but also strategies for enhancing liquidity in the KOSPI 200 index options market, for compensating the defects of V-KOSPI 200. First, introducing market making scheme in the KOSPI 200 options market can be the direct solution to prevent temporary fluctuations and spikes of the index arising from abnormal orders and to alleviate unnatural low variability (level) of the index through decreasing the use of stale market prices (model prices). Second, if weekly options underlying KOSPI 200 index are available for trading and investor interest in the weeklys are surged, Korea Exchange can enhance V-KOSPI 200 to include series of KOSPI 200 weekly options. The inclusion for at least 5~6 weekly options available for trading allow V-KOSPI 200 to be calculated with KOSPI 200 index option series that most precisely match the 30-day target time-frame for expected volatility that the Index is intended to represent. Along with these strategies for enhancing liquidity in the KOSPI 200 index options market, the study suggests the methodology which can prevents temporary fluctuations and spikes of the index by substituting stale or abnormal prices for normal prices.