Seven Years Study of the Seasonal Dynamics of Zooplankton Communities in a Large Subtropical Floodplain Ecosystem: A Test of the PEG Model

Irregular hydrological events, according to a classic plankton ecology group (PEG) study, can generate major deviations from the standard PEG model. However, little is known about the function of hydrological factors in influencing the seasonal dynamics of plankton. We used multivariate and Partial Least Squares Path Modeling to analyze the seasonal variation in crustacean zooplankton and related environmental factors from winter 2009 to winter 2016 in Lake Poyang, the largest freshwater lake in China. We found a distinct seasonal pattern in zooplankton development, which deviated, in part, from the PEG model, as we found indications of (1) a weaker degree of food limitation in winter and spring, likely due to high concentrations of allochthonous sources caused by decomposition of seasonally flooded hygrophytes, also affecting sediment dynamics; (2) a peak in crustacean zooplankton biomass in summer when the water level was high (and predation was lower), and where horizontal transport of zooplankton from the littoral zone to the pelagic was possibleand (3) a higher predation pressure in autumn, likely due to a shrinking water volume that left the fish concentrated in less water. The majority of these differences can be attributed to the direct or indirect impacts of physical factor variation.

ASSESSMENT OF THE INFLUENCE OF THE THERMODYNAMIC FACTOR ON THE CRYSTALLIZATION PROCESS IN A VACUUM APPARATUS

Особенность состояния системы жидкость–твердое тело в метастабильном растворе вещества состоит в том, что она (система) претерпевает два фазовых превращения в вакуум-аппарате (ВА) – кристаллообразование и растворение, требующие экспериментального изучения и описания в силу их важности при совершенствовании технологии производства кристаллического сахара. Однако и теоретическое обоснование фазовых превращений в метастабильном растворе разработано недостаточно. В статье предпринята попытка количественно поставить и решить проблему учета возникающего при проведении обработки метастабильного сахарсодержащего раствора повышения температуры в результате конденсации молекул на центре концентрации при пересыщении в ВА. В качестве основы численного моделирования поставленной задачи использовали программные продукты информационной среды Mathcad. С использованием модели диффузионного массопереноса сахарозы в пересыщенном растворе к затравке был разработан алгоритм расчета зависимости массы сахарозы от времени проведения процесса кристаллизации. На примере сахарозы дана оценка влияния физического фактора – выделяющейся при кристаллообразовании теплоты на расчет теплового баланса и производительности ВА. The peculiarity of the state of the liquid-solid system in a metastable solution of a substance is that it (the system) undergoes two phase transformations in a vacuum apparatus (VA) – crystal formation and dissolution, requiring experimental study and description due to their importance in improving the technology of production of crystalline sugar. However the theoretical justification of phase transformations in a metastable solution has not been sufficiently developed. The article attempts to quantify and solve the problem of taking into account the temperature increase that occurs during the processing of a metastable sugar-containing solution as a result of condensation of molecules at the concentration center during supersaturation in VA. Software products of the Mathcad information environment were used as the basis for numerical modeling of the task. Using a model of diffusive mass transfer of sucrose in a supersaturated solution to the seed, an algorithm was developed for calculating the dependence of the sucrose mass on the time of the crystallization process. On the example of sucrose, an assessment of the influence of a physical factor – the heat released during crystallization on the calculation of the thermal balance and the productivity of the VA is given.

Influence of physicochemical factors on water exchange in cotton leaves under the moisture deficit conditions

Presowing treatment of cotton seeds with a physical factor (low-frequency electromagnetic field - LF EMF) and a chemical compound (glycyrrhizic acid - GzA) and sowing them under conditions of optimal and limited water supply showed that different varieties of cotton, depending on their biological peculiarities and the method of seed treatment, had different parameters of water exchange in plants. The experiments were carried out in laboratory, greenhouse, lysimetric and field conditions, the indicators of the electrical resistance of leaf tissues (ERLT) of cotton plants depended on the conditions of water supply. According to this indicator, the varieties Ishonch, Gulbahor-2 and Navbahor-2 showed greater resistance to soil moisture deficiency, in comparison with the variety Tashkent-6. The plant varieties from seeds, treated with LF EMF and GzA, to a greater or lesser extent, are in the range with the lowest ERLT values, in comparison with the varieties from untreated seeds.

Physiologically based control of the process of gentle light awakening

The well-being of a person and the efficiency of his production activities are largely determined by the correspondence of the biorhythms of a person to his working schedule. As it was established at the molecular and genetic level, the main physical factor that allows us to control human biorhythms is light (Nobel Prize 2017). Modern studies of ophthalmologists have found a third type of photoreceptors in human eyes, in addition to rods and cones. These receptors are not intended for receiving images, but primarily for correcting biorhythms, including controlling the process of awakening. The third type of receptors are sensitive mainly in the short-wave, blue region of the visible spectrum. In recent years light-emitting diodes have appeared. However, these devices do not take into account the current requirements for the spectrum of the awakening radiation, and even more so do not allow it to be adjusted during the awakening process according to the necessary program. We offer a technology for gentle awakening of the employee, based on modern concepts of ophthalmology and biorhythmology. The technology uses computer control of the physical factors of awakening-light and sound.

Model simulations of arctic biogeochemistry and permafrost extent are highly sensitive to the implemented snow scheme in LPJ-GUESS

The Arctic is warming rapidly, especially in winter, which is causing large-scale reductions in snow cover. Snow is one of the main controls on soil thermodynamics, and changes in its thickness and extent affect both permafrost thaw and soil biogeochemistry. Since soil respiration during the cold season potentially offsets carbon uptake during the growing season, it is essential to achieve a realistic simulation of the effect of snow cover on soil conditions to more accurately project the direction of arctic carbon–climate feedbacks under continued winter warming. The Lund–Potsdam–Jena General Ecosystem Simulator (LPJ-GUESS) dynamic vegetation model has used – up until now – a single layer snow scheme, which underestimated the insulation effect of snow, leading to a cold bias in soil temperature. To address this shortcoming, we developed and integrated a dynamic, multi-layer snow scheme in LPJ-GUESS. The new snow scheme performs well in simulating the insulation of snow at hundreds of locations across Russia compared to observations. We show that improving this single physical factor enhanced simulations of permafrost extent compared to an advanced permafrost product, where the overestimation of permafrost cover decreased from 10 % to 5 % using the new snow scheme. Besides soil thermodynamics, the new snow scheme resulted in a doubled winter respiration and an overall higher vegetation carbon content. This study highlights the importance of a correct representation of snow in ecosystem models to project biogeochemical processes that govern climate feedbacks. The new dynamic snow scheme is an essential improvement in the simulation of cold season processes, which reduces the uncertainty of model projections. These developments contribute to a more realistic simulation of arctic carbon–climate feedbacks.

Expression of the Melatonin-Associated Genes in Fibroblasts That Have Been Co-Exposed to Fluoride and a Moderate-Strength Static Magnetic Field

Fluoride can weaken the protective role of melatonin in reducing cellular damage. A static magnetic field is a physical factor that can counteract the negative effect of fluoride. Hence, the main objective of the study was to analyze the transcriptional activity of the genes that are associated with the activity of melatonin in human skin fibroblasts that have been co-exposed to fluoride and a moderate-strength static magnetic field. The expression of the melatonin-associated genes in human fibroblasts that had simultaneously been exposed to F− and a static magnetic field was determined using an oligonucleotide microarray and RT-qPCR techniques. The concentration of oxidative damage markers was also measured. In NaF and static magnetic field-treated cells, there was a tendency to compensate for the expression of the differentiating genes (IL27RA, NR1D1, RRP7A, YIPF1, HIST1H2BD) that had been modified by the presence of fluoride. It has been also shown that the oxidative damage marker concentration was statistically lower in the cells that had simultaneously been exposed to fluoride and a static magnetic field compared to the F-treated cells. In conclusion, the protective role of a moderate-strength static magnetic field on human dermal fibroblasts that had been exposed to fluoride was demonstrated, and its mechanism of action is associated with the melatonin-dependent pathways.

Ionic Liquids, Loosened the Coconut Shell Rigidity to Boost up the Biofuels Productivity

Recently, a continuous rising awareness among human community to an environmental issue had changed the frame of current scenario and shifted a whole attention of research community towards the sustainable energy options & selecting the greener-solvents technology like Ionic-Liquids (ILs). An ionic-liquid technology known to augment the biorefineries pre-processing step mainly targeted to dissolute the complex and rigid structure of lignocellulosic biomass and promote to produce an economically valuable biofuels. 1-Butyl-3methylimidazolium acetate [BMIM][COO−] and 1-Butyl-3-methylimidazolium chloride [BMIM][Cl−] (ILs) were extensively studied in a current research study. Studied Ionic-liquids have a great capacity to fractionate the plant cellular components by employing the process of delignification, as it can be depicted through an evaluation of degree of cellulose-crystallinity index. Current study exploits an aqueous-ionic-liquid technology, where a combined reaction mixture of deionized-water, ionic-liquids (ILs) and biomass load-size were used in (1:10:1) ratio under vacuum. An observed result of the study determined the Total reducing sugar (TRS) content and residual lignin yield after employing the ILs pretreatment. It estimate yield of Total reducing sugar (46.6%) and residual lignin (36.25498%) in S-12 shell biomass pretreated with [BMIM][COO−] at 120°C for 2.5h under vacuum. Although, Taguchi approach significantly notified the affect of process parameters during the ILs pretreatment processing. In this context, water-content (wt%) had found the most dominant physical factor instead of, temperature and time-duration. This research study also finds the S-12[BMIM][COO−], an effective biomass candidate compared to other studied biomasses to achieve the high biofuel yield in a cost-effective manner.

The Effect Of Noise On The Level of Concentration In Wood Cutting Workers In Arjasa District, Jember District

Disorders of concentration in workers can cause workplace accidents due to decreased ability to focus attention when working. The annual work accident rate is estimated at 250 million with 1.2 million people dead. One of the causes of disturbances in worker concentration is the physical factor in the form of noise. One of the high intensity noise is found in the wood cutting industry in Arjasa District, Jember. The aim of this study is to analyze the effect of noise on the concentration level in wood cutting workers in Arjasa District, Jember. This is an analytic observational research with cross sectional study. The respondents amounted to 32 people taken with purposive sampling. The measurement of noise was using a sound level meter. The measurement of concentration level using Trail Making Test (TMT) A and B. Concentration level measurement is done when the respondent has worked for 30 minute. The results of the study showed that the majority of respondents were aged between 25-28 years (28.1%) and had worked less than the same as 2 years (53.1%). The average noise intensity of the wood cutting area was 97.5 dB (A) and the loading and unloading area was 76.2 dB (A). Average noise intensity of the wood cutting area exceeds the noise threshold value. The level of concentration of workers in the wood cutting area is lower than the loading and unloading area workers. The results of data analysis using the independent t test indicate that there are differences in the mean TMT B score: TMT A between respondents who work in noisy and non-noisy environments (p=0,004). There was a noise effect on the concentration level in wood cutting workers in Arjasa District, Jember Regency. Keywords: Noise, concentration, wood cutting workers

Engineering Physical Factor Considerations for Specifying Dam Type During Memve’ele Dam Construction (South-Cameroon).

This paper presents the results of engineering investigations used to select a best design for the Memve’ele dam. The selection of Memve’ele dam type has been based on consideration of physical factors such as topography, climate, availability of construction material, geology, geotechnical and foundation conditions and the selection of optima alternative between three dam types. According to these factors, Memve’ele valley is very wide and situated in the warm climate zone with dry and rainy seasons favorable to embankment type dam; the geology reveals very good conditions with Ntem formations and residual deposits as foundation materials and the dam site is not influenced by earthquake; this behavior is confirmed by geotechnical data and further indicates that this site is favorable to a composite dam type (embankment and concrete dams or connecting concrete structures) and the construction materials found within or near the dam site are suitable for usage. These characteristics have contributed retaining three dam types. The alternative of these three dams is a composite dam type option including homogeneous earth dam and rock fill dam with central core link by concrete structures. Engineering geological map and general layout of Memve’ele’s dam highlight the important role plays by engineers. The main dam that is observed actually in the Memve’ele dam site is composed from left to right of left connecting dam section, flushing sluice, main spillway section, riverbed dam section, auxiliary spillway section and right bank dam section.