Characteristics of perch fish diet in small lake of Lake Onega catchment area

Fish feeding process is studied as one of the links in the transformation of the energy of a water reservoir, as one of the factors that determine the ecology of fish and make an imprint on the morphology, physiology and behavior of fish, or as one of the criteria, which help the most rationally use natural resources of the water bodies. The results of work carried out by the Northern Water Problems Institute (NWPI KarRC RAS) and Petrozavodsk State University (PetrSU) within the framework of state assignments, forecast problems and economic contractual topics on assessing the nutrition of perch species (perch, ruff) in some lakes of the Konchezero group (South Karelia), in particular Lake Munozero, which is part of the lower reaches of the river Shuya belonging to the catchment area of Lake Onega. The work was carried out by the experts from the IWPS KarRC RAS and PetrSU in 2018-2020. Its main hydrological and ichthyological indicators have been studied. The reconnaissance fish productivity of Lake Munozero based on the development of the forage base at the present stage is estimated as 9 kg/ha. The feeding spectra of ruff and perch in the lake overlap only with respect to eggs, the ruff using eggs more actively. Predation is peculiar only to perch, while even fish whose size is less than 14 cm (the average size of the transition to predation for Karelia) hunt at a time when there is a lot of other food in the reservoir. As the perch passes to summer feeding, its diet becomes more diverse. Some benthic organisms are replaced by others, an air fraction appears, the perch's diet includes fish in summer and spring; nutrition becomes more active: the average stomach fullness index increases from 7.3 to 145.6‰.

Supporting Premature Infants’ Oral Feeding in the NICU—A Qualitative Study of Nurses’ Perspectives

One major task in the neonatal intensive care unit (NICU) involves ensuring adequate nutrition and supporting the provision of human milk. The aim of this study was to explore nurses’ experiences of the oral feeding process in the NICU when the infant is born extremely or very preterm. We used a qualitative inductive approach. Nine nurses from three family-centered NICUs were interviewed face-to-face. The interviews were transcribed verbatim and analyzed using content analysis. Five sub-categories and two generic categories formed the main category: ‘A complex and long-lasting collaboration.’ The nurses wished to contribute to the parents’ understanding of the feeding process and their own role as parents in this process. The nurses’ intention was to guide and support parents to be autonomous in this process. They saw the family as a team in which the preterm infant was the leader whose needs and development directed the feeding and the parents’ actions in this process. Written and verbal communication, seeing all family members as important members of a team and early identification of the most vulnerable families to direct the emotional and practical feeding support accordingly can strengthen the feeding process in the NICU.

Antenatal Antibiotic Exposure Affects Enteral Feeding, Body Growth, and Neonatal Infection in Preterm Infants: A Retrospective Study

Background: Antibiotics are widely prescribed by obstetricians, which exposes a large number of infants to antenatal antibiotics (AAB). The effect of AAB on various aspects of neonatal development of preterm infants remains unclear.Methods: In this retrospective study, infants born with gestational age (GA) between 22 +0 and 36 +6 weeks at our unit from 2017 to 2019 were included. Multivariable analysis was adopted to examine the associations between AAB exposure and various outcomes related to enteral feeding process, body growth, and neonatal infection after adjusting for potential confounders. Further subanalysis on the exposure level of AAB and stratified analysis by GA (<34 vs. ≥34 weeks) were also conducted.Results: In this cohort comprising 2,543 preterm infants, AAB was associated with decreased risks of feeding intolerance (odds ratio [OR]: 0.63, 95% confidence interval [CI]: 0.48–0.82) and neonatal infection (OR: 0.63, 95% CI: 0.41–0.94). Higher AAB exposure level was associated with higher Z scores of birth weight (β = 0.37, 95% CI: 0.27–0.47), but lower Δbodyweight Z-scores (β = −0.20, 95% CI: −0.27 to −0.13). AAB was positively associated with the parameters related to body growth in infants with GA <34 weeks but negatively associated in those with GA ≥34 weeks.Conclusions: AAB exposure affects the enteral feeding process and neonatal infection. The effects on body growth vary by the exposure level of AAB and GA of infants. A well-designed prospective and preferably multi-centre study with predefined parameters is required to confirm our findings.

New single vortex generation method for flame/vortex interaction using flow behind a rotating cylinder

This paper investigates a new experimental method to generate a single two-dimensional translated vortex for flame/vortex interaction studies. A rotating cylinder is immersed in a uniform flow and, its rotating speed is impulsively reduced. This sudden action triggers the generation of a single vortex when both the initial and the final rotation speeds are in the range of a steady-state regime. Flow visualization allows confirming the applicability of this method, while a complementary two-dimensional numerical simulation is conducted to understand the vortex formation process. A vorticity layer is detached from the cylinder, initiating a feeding process and gradual growth of a single leading vortex. The feeding process is saturated at a specific distance from the cylinder and, vortex separation from the vorticity layer is observed. At the final stage of the formation process, the generated vortex is advected away and, a steady-state regime is again established behind the cylinder. The vortex characteristics appear to be related to the normalized reduction in the rotation rate ∆α, defined as the initial and final rotation rates difference normalized by the initial rotation rate. Several combinations of initial and final rotation rates corresponding to different normalized reductions are investigated experimentally and numerically. The results allow understanding the effect of this parameter; a higher normalized reduction generates a stronger, more rapidly growing vortex. However, its trajectory is related to the wake deviation corresponding to the final rotation rate.

Designing and Simulating the Control Process of a Feed Pusher Robot Used on a Dairy Farm

Feeding cattle on livestock farms is a labor-intensive operation that requires considerable capital investments to purchase equipment and cover labour costs. The global trends in developing technological equipment for feeding cattle include the robotization of various processes. The operation of feed pushing on the feeding table is an integral part of the feeding process, which has a significant impact on livestock productivity. This study concentrates on the simulation modeling of a feed pusher robot using Simulink tools in the Matlab environment to facilitate robot modernization or optimize the final cost for artificial testing of typical system elements and reduce production costs. Based on a simulation model, an experimental sample was designed with a controlled dispenser of feed additives, which can significantly facilitate the feeding process and optimize the dosing of concentrated additives.

Automation Design of Kentongan Sound for The Feeding Process of Vaname Shrimp Farming in Pond

Feeding on vanamei shrimp culture in pondsis carried out on average 4 to 5 times a day. In aquaculture activities with a large number of ponds, the sound of kentongan becomes a time reference for the operator in providing feed. The purpose of this article was to describe the process required to turn the kentongan sound into a command input for an automatic feeder. The sound of kentongan will be used as input data (commands) for the microcontroller is translated as a command for the feeder to carry out its activities of feeding. The methodology used the following points: first, field observations of the use of kentongan sounds as a sign of the feeding process for feed operators; second, literature study covering sound frequency and sensor system; third, the creation of a chart in the form of step by step logic from input in the form of kentongan sounds to the process of feeding using an automatic feeding device; fourth, the design of the hardware that will be used and the creation of the software in the form of a command flow chart. The result was realized in the form of a chart from input in the form of kentongan sounds to the process of feeding using an automatic feeder. This includes hardware and software design. There were two important things in automation design. The identification process of kentongan sounds becomes a function of frequency against time, where this frequency had certain characteristics which were expressed by graphs that have certain equation values. This kentongan sound with a certain frequency will be the input for the microcontroller to carry out its task of giving orders to the feeding device to provide feed for vanamei shrimp in ponds.

Robust optimal control of a nonlinear impulsive time-delay system for 1,3-PD fed-batch culture

In this paper, taking the feeding process as a form of impulsive and considering the time-delay in fermentation process. A robust model with the time-delay system as the control variable and the time-delay system as the constraint is established. In order to solve this optimal control problem, we have propose an particle swarm optimization method to solve problem. Numerical results show that 1,3-PD yield at the terminal time increases compared with the experimental result.

An automated system development to control the device for supplying slag-forming mixture into mould of CCM

The mechanism of feeding slag-forming mixture (SFM) with a pneumatic drive has a number of disadvantages associated, in particular, with the uneven supply of the mixture into mould. To eliminate the drawbacks, mixture feeding device with an electric drive was designed to eliminate them. In order to ensure control of the SFM feeding process, an automated system has been developed that provides real-time information on the technological process of feeding the mixture into the mould of continuous casting machine, including speed of rotation of screw drive motors and movement of carriage, the level of the mixture in the bunkers and its consumption, temperature of the metal and slag. A software and hardware complex (SCADA-system) has been developed, which makes it possible to analyze the components of the mixture in the “online” mode and take into account the effect of changes in the supply of each of them on its composition. The dependence of the mixture consumption rate on the casting rate has been established, which can be displayed on the screen in the current mode. Application of the SCADA-system made it possible to control the developed SFM feeder both in manual and automatic modes. It was shown that the implementation of the developed automated SFM feeding device in the steelmaking production of Ural Steel, JSC will secure decreasing the SFM consumption by 2.8% and decreasing downtime by 5% due to increasing efficiency of fault detection with a total implementation cost of 200 thous. rubles.

PSIX-16 Association between Thrombin and horn fly abundance in beef cattle

It has been reported that differences in horn fly tolerance in beef cattle could be associated with variation in blood enzymes. Thrombin (TH), a major enzyme for hemostasis that plays an important role in the activation of several pro-coagulation factors through the conversion of fibrinogen to fibrin, has been associated with horn fly prevalence on cattle. Although this assumption is reasonable, as fast-coagulating blood tends to complicate the feeding process for flies, there is little meaningful field data that clearly supports this hypothesis. Therefore, the objective of this study was to assess TH levels in relation to horn fly abundance using 360 cows at two University of Georgia farms (Northwest Georgia REC, 34.5°N, 85.0°W and Eatonton Beef Research Unit, 33.4°N, 83.5°W). Horn fly counts were taken twice by trained evaluators during the summer of 2019 (June and August). Additionally, blood samples were collected twice on each cow to quantify serum TH levels using an ELISA assay (MyBioSource, San Diego, CA). The Pearson correlation between serum TH level and horn fly count was -0.19, indicating a decrease in the number of flies with increasing TH in the blood. In order to reduce the impact of the uncertainty associated with the subjective assessment of horn fly abundance and the potential nonlinear relationship between both parameters, TH was categorized into four classes (1=TH >500 ng/mL; 2=250< TH< 500 ng/mL; 3=100< TH< 250 ng/mL; 4=< 100 ng/mL). Average fly counts were 336, 353, 391, and 464 for the four classes, respectively. Between the first (high TH) and fourth (low TH) classes, there was a 38% reduction in fly abundance. Across sire families, fly abundance ranged between 190 and 650. Collectively, these results indicate that selection for higher serum TH levels could be used as a proxy for improving horn fly tolerance in beef cattle.

Development of a Controlled Continuous Low-Dose Feeding Process

This paper proposes a feed rate control strategy for a novel volumetric micro-feeder, which can accomplish low-dose feeding of pharmaceutical raw materials with significantly different powder properties. The developed feed-forward control strategy enables a constant feed rate with a minimum deviation from the set-point, even for materials that are typically difficult to accurately feed (e.g., due to high cohesion or low density) using conventional continuous feeders. Density variations observed during the feeding process were characterized via a displacement feed factor profile for each powder. The characterized effective displacement density profile was applied in the micro-feeder system to proactively control the feed rate by manipulating the powder displacement rate (i.e., computing the feed rate from the powder displacement rate). Based on the displacement feed factor profile, the feed rate can be predicted during the feeding process and at any feed rate set-point. Three pharmaceutically relevant materials were used for the micro-feeder evaluation: di-calcium phosphate (large-particle system, high density), croscarmellose sodium (small-particle system, medium density), and barium sulfate (very small-particle <10 μm, high density). A significant improvement in the feeding performance was achieved for all investigated materials. The feed rate deviation from the set-point and its relative standard deviation were minimal compared to operations without the control strategy.