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Author(s):  
O. Perinek ◽  
G. Shiryaev

The aim of the research is to determine the effect of changes in the concentration of estradiol-17β on the concentration of vitellogenin at the stage of egg shell formation and preparation of the body of meat and egg breed chickens (for example, the Pushkin breed) for ovulation.Materials and methods. The material for the study was the Pushkin breed chickens, in the amount of 28 heads. at the age of 48 weeks. Chickens were kept in individual cages. Light mode - 14C:10T. Drinking - nipple, temperature in the house and feeding - according to the standards adopted in the bioresource collection of RRIFAGB "Genetic collection of rare and endangered chicken breeds." Within 10 days prior to blood sampling, an ultrasound scan of the ovary and oviduct was performed from the studied group of chickens, which made it possible to determine the stage of egg formation. Blood from the studied chickens was taken in the morning on an empty stomach for the simultaneous determination of the concentration of estradiol and vitellogenin at the stage of egg shell formation. The concentration of estradiol and vitellogenin in the blood plasma of chickens was determined by ELISA. To clarify the effect of the concentration of estradiol (E2) on vitellogenin (VTG), the studied flock was divided into 2 groups according to the concentration of vitellogenin: 1st gr. – > Mav. (> 20 μg / ml) and 2nd gr. – < Mav. (<20 μg / ml). During the study period, eggs of chickens were evaluated according to the following morphometric parameters: the weight of the egg, yolk, protein and shell, elastic deformation, shape index, density of protein fractions, thickness of the shell and subshell, marbling. The number of eggs laid was determined in 10-day trial period.Results. It has been established that the duration of the ovulatory cycle in Pushkin breed chickens is 27-29 hours. As a result of such a long ovulatory cycle in the following days, laying of eggs occurs later with a progressive shift, as a result of which the laying cycle on average for the studied group of chickens is 3 days. The E2 level in the 1st group was 258,48 ± 30,60 pg/ml (p < 0,05), which significantly differed from the 2nd group – 181,45 ± 13,81 pg/ml. A positive correlation was found between VTG and E2, r = 0,5 (p < 0,001).Conclusion. The VTG level significantly increases in Pushkin chickens at the age of 48 weeks with an increase in the concentration of E2 in the blood. A positive correlation was noted between these features. According to the results of our research, the high content of estradiol and vitellogenin in the chickens blood serum did not have a significant effect on egg productivity.


2021 ◽  
Vol 20 (3) ◽  
Author(s):  
V.R. Yosypenko ◽  
R.Ye. Bulyk ◽  
M.I. Kryvchanska ◽  
Y.R. Lukan

Purpose – to study the changes in the ultrastructure of neurons of the lateral preopticnucleus (LPON) of the hypothalamus of old rats under various light conditions.Material and methods. The experiments were carried out on 36 old white male rats.The material was fixed in a 2.5% solution of glutaraldehyde, prepared on the basisof phosphate buffer with a pH of 7.2–7.4. Then, postfixation was performed in a 1%solution of osmium tetraoxide and dehydrated in propylene oxide, after which it waspoured into a mixture of epoxy resins. Ultrathin sections made on an ultramicrotomeLKB-3 were contrasted with uranium acetate and lead citrate according to the Reynoldsmethod and studied under electron microscope TEM - 125 K.Results. Studies of LPON neurons under the standard light mode revealed nuclei withuneven contours. The nucleoli are quite large. The neuroplasm contains well-developedtubules of the rough endoplasmic reticulum (ER) and small cisternae of the Golgi complex(GC). Mitochondria are rounded, small, with moderately pronounced cristae. Underconditions of round-the-clock darkness, we have found that the cell nuclei are rounded,less often determined by the nucleoli. In the neuroplasm there are locally dilated tubulesof the ER and cisternae of the GC, mitochondria with enlightened matrix and fragmentedcristae. Under conditions of round-the-clock illumination, the nuclei of the rounded formwith uneven contours of a nuclear membrane forming deep intussusception are revealed.Nucleoli were rarely identified. In the hyaloplasm, locally dilated tubules of the ERare identified. Mitochondria are small in size with an enlightened matrix and reducedcristae.Conclusions. The obtained results of submicroscopic examination of LPON neuronsof the hypothalamus of old rats revealed their relatively increased functional activityin the dark period. Under conditions of round-the-clock lighting, more pronouncedhypertrophic and initial destructive changes of the nuclei and organelles of the neuronsof the LPON of the hypothalamic were revealed, compared with the animals that wereunder the conditions of round-the-clock darkness. This is confirmed by the change in theultrastructure of nerve cells at 2 am the appearance of "dark" cells.


2021 ◽  
Vol 19 (2) ◽  
pp. 79-83
Author(s):  
A. A. Pobedinsky

The constant growth in the number of cars and trucks in single industry towns is forcing road design engineers to find ways convenient for all road users and pedestrians to move at intersections. Fulfilling such conditions is a difficult task but it can be solved, especially if there are many T-shaped intersections along the entire length of the road. Most often they are located along the line of railways, heating mains, river or lake banks, parks, etc. Since there are no adjacent roads, it is possible to ensure continuous movement of cars, but only in one direction.The objective of this work is to substantiate the project aimed at ensuring unhindered traffic at T-intersections of vehicles following 50 let VLKSM street in the city of Tyumen.To achieve this objective, the method of observation and recording, as well as the analysis of operation of optical devices that regulate passage of cars at intersections were used. With newly designed travel mode, there is no infringement of rights in relation to other motorists and pedestrians since the traffic light mode for the rest of segments keeps the same counting in seconds. A system of safe pedestrian crossing is envisaged along with an improvement in the environmental component of the whole city.For initial adaptation of motorists to new conditions, it is proposed to use a side green vertical arrow attached to the traffic light and signal columns that delimit traffic lanes for a «slow merge» into the flow of those leaving the secondary road. An undeniable advantage of this type of design is the minimum cost of reconstruction of intersections. Based on author’s own observations, it can be argued that this project increases traffic of vehicles moving from the central part of the city to the eastern part by 1,5–1,8 times. 


Author(s):  
T. Gou ◽  
L. Xu ◽  
W. Wang ◽  
L. Zhang ◽  
Y. Lu ◽  
...  
Keyword(s):  

2021 ◽  
Vol 11 (11) ◽  
pp. 4777
Author(s):  
Annabell Heintz ◽  
Sebastian Sold ◽  
Felix Wühler ◽  
Julia Dyckow ◽  
Lucas Schirmer ◽  
...  

Multimodal imaging gains increasing popularity for biomedical applications. This article presents the design of a novel multimodal imaging system. The centerpiece is a light microscope operating in the incident and transmitted light mode. Additionally, Raman spectroscopy and VIS/NIR reflectance spectroscopy are adapted. The proof-of-concept is realized to distinguish between grey matter (GM) and white matter (WM) of normal mouse brain tissue. Besides Raman and VIS/NIR spectroscopy, the following optical microscopy techniques are applied in the incident light mode: brightfield, darkfield, and polarization microscopy. To complement the study, brightfield images of a hematoxylin and eosin (H&E) stained cryosection in the transmitted light mode are recorded using the same imaging system. Data acquisition based on polarization microscopy and Raman spectroscopy gives the best results regarding the tissue differentiation of the unstained section. In addition to the discrimination of GM and WM, both modalities are suited to highlight differences in the density of myelinated axons. For Raman spectroscopy, this is achieved by calculating the sum of two intensity peak ratios (I2857 + I2888)/I2930 in the high-wavenumber region. For an optimum combination of the modalities, it is recommended to apply the molecule-specific but time-consuming Raman spectroscopy to smaller regions of interest, which have previously been identified by the microscopic modes.


2021 ◽  
Vol 334 ◽  
pp. 01034
Author(s):  
Dmitriy Karmanov ◽  
Dmitriy Zakharov ◽  
Andrey Chistyakov

The article is devoted to improving the quality of life in cities by implementing the concept of an “intelligent” city and developing an automated transport infrastructure. The following factors are considered in the work: the traffic intensity of vehicles and the mode of operation of traffic signal regulation. In work, the mode of operation of a traffic light is determined by an adaptive method. The main tool for increasing the capacity is the choice of the optimal ratio of phase coefficients and the optimal cycle time. Considered the influence of capacity on the parameters of road traffic, the environmental load from automobile transport. The dependence of the traffic parameters for different cycle times is established. A change in fuel consumption and in the content of harmful emissions for various traffic light modes is given. The justification is given for the necessity to change the traffic light mode after increasing the number of lanes in the street road network.


Electronics ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 1649
Author(s):  
Chun-Te Lee ◽  
Ping-Tsan Ho

In general, the sensor lamps in the corridors, stairwells, or toilets of buildings will change from completely dark to full brightness when someone passes by. It will make the human eyes feel very uncomfortable, and when the sensor lamp is completely dark, the whole corridor and stairwell will be dark, making women and children feel insecure at night. If the lighting is changed to be sensor-less, there is a serious problem of wasted energy. To solve this dilemma, we developed a new type of “LED sensor lamp with low-light mode” that changes the original “full dark mode” to “low-light mode”. As such, when someone approaches the sensor lamp, their eyes will not be uncomfortable with the momentary illumination. Furthermore, when no one passes by, the sensor lamp will stay in low-light mode, so that people returning home at night no longer have to go through dark corridors, thereby achieving safety, aesthetics, and energy-saving purposes. This new sensor lamp’s power consumption in low-light mode is only 1/10 of the high-light mode, but its brightness can be up to half of the high-light mode, making it very suitable for parking lots, corridors, stairways, or toilets of buildings. It only requires the replacement of the lamp but not the original lamp socket, yet the basic brightness can be maintained. Take the general 15W T8 LED lamp (sensor-less) as an example: if it is replaced by this new type of sensor lamp, and the place where it is installed is rarely passed by people, the power saving rate will be as high as 90%. Assuming that there are 12 passers-by per hour, the saving rate is still 81%.


Author(s):  
V.V. Zhuravleva ◽  
A.S. Manicheva ◽  
A.A. Martynova

The problem of predicting changes in the intensity of photosynthesis associated with changes in the lighting mode, atmospheric carbon dioxide concentration, and the temperature is urgent. Appropriate models can help choose the optimal mode of growing plants in protected soil, as well as serve as a basis for predicting the consequences of global climate change. It is noted that in the conditions of protected soil, the most significant factor is the illumination of plants. The aim of the research is to construct an algorithm for additional illumination of plants in protected ground conditions based on a mathematical model of photosynthesis. The authors introduced the value of the efficiency of additional illumination and studied its dependence on the coefficient of light transmission of the roof. The solution of the main task of the study is achieved by the fact that the light mode in protected ground structures is carried out on the basis of additional illumination to the ideal (optimal) for this type of plant. The entered value of the efficiency of additional illumination shows what energy costs will be for the production of photosynthesis products and, as a result, allows estimation of the economic costs. The considered method of artificial lighting of plants makes it possible to effectively use both sunlight and artificial lighting, providing an optimal lighting mode all year round, and allows to increase the intensity of photosynthesis by 50-80 %.


2020 ◽  
Author(s):  
Claudia Climent ◽  
Johannes Feist

<div> <div> <div> <p>Recent experiments have reported modified chemical reactivity under vibrational strong coupling (VSC) in microfluidic Fabry-Pérot cavities. In particular, the reaction rate of nucleophilic substitution reactions at silicon centers (S<sub>N</sub>2@Si) has been altered when a vibrational mode of the reactant was coupled to a confined light mode in the strong coupling regime. In this situation, hybrid light-matter states known as polaritons are formed and seem to be responsible for the modified chemical kinetics. These results are very encouraging for future applications of polaritonic chemistry to catalyze chemical reactions, with the ability to manipulate chemical phenomena without any external excitation of the system. Still, there is no theory capable of explaining the mechanism behind these results. In this work we address two points that are crucial for the interpretation of these experiments. Firstly, by means of electronic structure calculations we report the reaction mechanism in normal conditions of the two recently modified S<sub>N</sub>2@Si reactions, obtaining in both cases a triple-well PES where the rate-determining step is due to the Si-C and Si-O bond cleavage. Secondly, we characterize in detail the normal modes of vibration of the reactants. In the VSC experiments, reaction rates were modified only when specific vibrations of the reactants were coupled to a cavity mode. We find that these vibrations are highly mixed among the different fragments of the reactants leading to a completely new assignment of the IR peaks coupled to cavity modes in the original experimental works. Our results are fundamental for the interpretation of the VSC experiments given that in the absence of a theory explaining these results, the current phenomenological understanding relies on the assignment of the character of the vibrational IR peaks. </p> </div> </div> </div>


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