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1
Zuleikha Eyvazova, Zuleikha Eyvazova, and Farhad Baydemirov Farhad Baydemirov. "RESEARCH ON THE IMPROVEMENTS OF CONSTRUCTION OF PUMP JACK WITH ONE-ARM SHOULDER." ETM - Equipment, Technologies, Materials 14, no. 02 (2023): 93–102. http://dx.doi.org/10.36962/etm14022023-93.
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In the production of oil by downhole rod pumps, as a drive, both in Azerbaijan and abroad, balancing one-arm and two-arm pump jack are most often used ones. In this article the goal is - a comparative study of the advantages of one-arm pump jack over two-arm pump jack. For that, the calculation of the main parameters was maid – displacenemt, speed and acceleration of suspension poin of rods and built comperative graphs for commercially avaible deaxial pump jack type of SKD8-3-4000 and the proposed construction of a one-arm pump jack. There are existing options, for holding a one-arm pump jack on the weight of the balancer when changing the stroke length of the suspension point of the rods that reviewed. Options for improving the one-arm pump jack are proposed.
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Tamila Xankisiyeva, Rauf Namazli, Tamila Xankisiyeva, Rauf Namazli. "PROCESSING OF THE TRIBO-UNIT OF THE REDUCER OF THE PUMP JACK." ETM - Equipment, Technologies, Materials 28, no. 04 (2025): 71–76. https://doi.org/10.36962/etm28042025-71.
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The surface component of this unit is the pump jack, which is designated to impart the reciprocating motion onto the polished rod and rod string. However, traditional beam unit is subjected to over torque and structural loading which can be drastically damaging. Moreover, conventional pump jacks pose many challenges in terms of energy consumption, large footprint, stroke length an speed control. Hence, considering hydraulic pumping units as an alterntive to traditional Pump jacks can improve the production operations and reduce energy requirements and HSE concerns. In this thesis, different hydraulic pumping units are initially studied and analyzed. Inspired by these technologies, a hydraulic unit is designed and simulated using Simulink/Matlab software with the aim of saving input energy. Various components were independently designed to optimize the performance and reduce the energy consumption. The unit was then simulated to activate a wire rope string as well as a conventional sucker rod string and their performance were compared with equivalent scenarios using a conventional Pump jack. The results show that the unit allows for more precise control of the pumping cycle in terms of pumping speed and stroke length. The energy consumption of the unit is also compared to conventional sucker rod pumping units operating at the same wellbore conditions, leading to significantly better results despite the greater pumping activity and higher productivity. Keywords: pump jack, hydraulic pumping unit, stroke length, energy consumption, footprint.
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Cai, Shaomin, and Wenping Cheng. "Design and Analysis of Harmonic Drive Reduction Pump Jack for Dynamic Performance in Oil Extraction." International Journal of Mechanical and Electrical Engineering 2, no. 1 (2024): 27–32. http://dx.doi.org/10.62051/ijmee.v2n1.04.
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The purpose of this study is to provide a high gear ratio reducing pump jack system, utilizing the characteristics of high transmission ratio and precision of harmonic drives, in order to improve the efficiency of low-permeability oil field extraction. A comparison was made between the new system and the conventional walking beam pump jack. The results showed that at a stroke length of 1.5 m and pumping frequencies of 4.5 min-1, 3.5 min-1, 2.5 min-1, 1.5 min-1, and 0.5 min-1, the maximum acceleration of the suspended load in the harmonic reducing pump jack was reduced by 20.79% compared to the conventional walking beam pump jack.
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Herlina, Herlina, Lies Banowati, and Teti Rahayu. "Rancang Bangun Pembuatan Alat Jack Hidrolik dengan Sistem Electrical Motor Driven Pump (EMDP) yang Menghasilkan Tekanan Fluida." Jurnal Informatika, Teknologi dan Sains 1, no. 1 (2022): 1–5. http://dx.doi.org/10.56244/formateks.v1i1.483.
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Jack hidrolik merupakan suatu alat yang berfungsi sebagai penopang beban-bebanyang sesuai dengan bobot yang telah ditentukan. Alat ini sangat berfungsi dan diandalkan didunia penerbangan khususnya dalam kegiatan melakukakan servis main landing gear,pemasangan wheels maupun maintenance pada pesawat. Fakultas Teknik Universitas NurtanioBandung khususnya Laboratorium General workshop memiliki peralatan jack, namun dalampelaksanaan kegiatan maintenance masih menggunakan jack manual yang kurang efektif. Alatini terdiri dari tiga bagian pokok, yaitu: Sistem electrical motor driven pump, hidrolik powerunit, dan mekanikal jack, dimana penulis hanya fokus pada pembuatan sistem electrical motordriven pump saja. Material yang digunakan pada pembuatan alat sistem electrical motor drivenpump ini meliputi komponen elektronika seperti switch, cable, fuse, CB, dan Baterai 24Vsebagai power supply utamanya. Jack hidrolik yang penulis buat mampu mengangkat bebanpada pesawat AS 202 BRAVO dengan beban 486 kg dan pesawat Cessna 401/402 denganbeban 2.813 kg.Keywords : Jack hidrolik, electrical motor driven pump, tekanan fluida
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Aliyev, Alesker M., and Sevda Y. Aliyeva. "Influence of mechanical factors on the performance and aging process of oil pump jack." Nafta-Gaz 79, no. 12 (2023): 776–85. http://dx.doi.org/10.18668/ng.2023.12.03.
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"The paper discusses the influence of mechanical factors on the performance and aging process of rocking machines, specifically focusing on oilfield equipment such as the downhole rod pump jack. The authors emphasize the importance of analyzing the condition and aging process of oilfield equipment to ensure reliability, safety, and efficiency in oil production processes. The mechanical factors discussed in the paper include vibrations, loads, wear, and corrosion. Vibrations can be caused by improper balance, bearing failures, or other factors, and they have a negative impact on equipment performance and can lead to breakdowns. High mechanical loads associated with raising and lowering sucker rods can cause wear and damage to the pump jack. Operating in harsh environments with sand, abrasive particles, or chemicals can also cause wear on surfaces and equipment parts. Corrosion of metal components can occur due to moisture, chemical attack, or improper storage and maintenance, leading to deterioration and breakage of equipment. The consequences of these mechanical factors on the aging of an oil pump jack include accelerated aging, decreased performance, and an increased risk of accidents. Continuous exposure to vibration, stress, wear, and corrosion accelerates the aging process, resulting in deterioration and reduced equipment life. Damage and breakdowns caused by mechanical factors lead to decreased efficiency, negatively impacting oil production processes. Moreover, insufficient maintenance and failure to address mechanical influences increase the risk of accidents, downtime, and damage to other parts of the manufacturing process. To assess the health and aging status of an oil pump jack, various analysis and diagnostic methods are used, including visual inspection, strength testing, monitoring of parameters, and non-destructive testing. Visual inspection helps identify visible damage, wear, and defects. Strength testing evaluates the reliability of pump jack parts and identifies potential issues. Monitoring parameters like vibrations, temperature, and pressure allows for detecting deviations from normal operation and preventing breakdowns. Non-destructive testing methods such as ultrasonic testing, magnetic particle testing, and radiography help identify hidden defects and damage. The authors recommend several strategies to maintain the reliability and efficiency of an oil pump jack. These strategies include implementing a preventive maintenance program with regular inspection, testing, and parts replacement based on manufacturer’s recommendations and equipment condition analysis. Determining optimal service and part replacement intervals based on historical data, monitoring results, and manufacturer’s recommendations is crucial. Additionally, utilizing more durable materials, anti-corrosion coatings, improved designs, and technologies can increase equipment resistance to mechanical stress and improve performance. The paper also describes the device and components of a pump jack, such as the installation base, platform, balancer, electric motor, crank, connecting rod, and control station. It emphasizes the importance of considering various characteristics when selecting and evaluating the effectiveness of a pump jack, including working load, maximum plunger stroke, reducer dimensions, output torque, and swing frequency. The kinematics of the pump jack drive system are discussed, highlighting the need for reconfiguration to adapt to changing operating conditions and optimize oil production performance. Overall, the paper emphasizes the importance of analyzing mechanical factors, managing the aging process, and implementing maintenance strategies to ensure the reliable and efficient operation of oilfield equipment, specifically the pump jack used in oil production processes.
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Sagdatullin, A. M. "POWER-EFFICIENCY ANALYSIS OF OIL WELL SYSTEMS WITH SUCKER ROD PUMPING UNITS." Oil and Gas Studies, no. 4 (August 30, 2015): 80–84. http://dx.doi.org/10.31660/0445-0108-2015-4-80-84.
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The purpose of this paper is to analyze the power efficiency of oil well systems with sucker rod pumping units. For this study a chain-drive of HRC 80-6-02 type and a similar performance drive HRC 80-6-02 balancer pumping unit were selected. Based on the analysis of the data, a conclusion was made that the power consumption for production of oil using ESP units is much higher due to a low coefficient of performance (COP) and significant losses in the submerged electric-driven pump. The analysis showed that for a half cycle of operation, i.e. per one stroke, the power consumption by a jack-pump was 15-20% higher than that of the chain drive. It is concluded that the chain drive is superior in many aspects of sucker-rod pumping units operation and may be the most effective replacement for ESP units, as well as for units with walking-beam jack pumps.
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Peter, Ufuoma Anaidhuno, Ochuko Ologe Solomon, and Erebugha Yerimearede Abraham. "The Design of a Simple 50 Tons Capacity Three Stage Telescopic Hydraulic Jack for Automobile and Vessel (Ship) Application." European Journal of Advances in Engineering and Technology 6, no. 8 (2019): 11–16. https://doi.org/10.5281/zenodo.10688443.
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<strong>ABSTRACT</strong> This research presents the design of a simple 50tons capacity three stage telescopic hydraulic jack for automobile and vessel (ship) application. Most hydraulic jacks are limited in capacity of load they can carry, in the quest to assist in solving the problem of heavy load lifting within a shortest time and to assist in carrying out maintenance activities onboard a vessel (ship). Lifting of the engine, press fitting of heavy components etc this simple design is considered very useful and safe. The objective of this research is to design a simple 50 tons capacity three stage telescopic hydraulic jack for automobile and vessel application using alloyed steel material, calculating for the minimum thickness that is safe in operation using Birnie’s equation of strain energy failure, considering tangential stress acting, and selecting the pump of 2HP for the operation.
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Malyar, Andriy, and Mykola Malyar. "Optimization of pump jack electric drive operation taking into account reservoir flow rate." Technology audit and production reserves 1, no. 1(81) (2025): 58–74. https://doi.org/10.15587/2706-5448.2025.322457.
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The object of the study are the processes occurring in electric drives of sucker rod pumping units, which are used for mechanical oil production. When designing oil pumping units, one of the issues is the synthesis of control systems for the electric drives of pump jacks. In the synthesis of the control system, it is important to take into account as many factors as possible that influence the performance of the well and its equipment. When synthesizing the criterion for optimal operation of the system, it is necessary to take into account changes in the technical condition of the oil production facility and the conditions of the reservoir operation. This is implemented using a control system that adjusts the electric drive speed according to the real operating conditions of the well. This approach allows improving the productivity of the oil pumping unit and increasing its economic efficiency. The main focus is on the synthesis of a control system for the electric drive of a pump jack, which makes it possible to balance the intensity of fluid inflow into the well and its withdrawal. An optimization criterion is proposed, which takes into account different fluid inflow rates, thus adapting the electric drive operation to the specific conditions of each well. The study used the theory of classical variational calculus. To find the minimum of the functional, and therefore the optimal parameters of the control system, a quadratic form, which is a Lyapunov function, was used. The study resulted in the formulae for calculating the key operational parameters of the pump jack electric drive. The synthesized optimization criterion links the unit's productivity to parameters such as the number of crankshaft rotations, the rod pump delivery coefficient, and the load torque of the drive motor. In practice, the proposed optimization criterion for the electric drive operation will enable improving the efficiency of the oil pumping unit through the rational selection of the drive motor's speed and torque. This, in turn, will enhance the well's operating conditions and extend its operational life.
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Kaverzina, Anna S., Konstantin V. Troyakov, Alexey Yu Ivanov, Artem A. Kardash, and Vyacheslav V. Rybin. "Pump jack balancing control method depending on the load." E3S Web of Conferences 471 (2024): 03011. http://dx.doi.org/10.1051/e3sconf/202447103011.
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This article focuses on the method of balancing the pump jack and optimizing its operation. In the course of the work, the main balancing methods were considered and a method based on changing the balancing value by moving the movable carriage was proposed. In the course of the work, a model was developed that made it possible to simulate loads, the results of which determined the effectiveness of the proposed balancing method. Based on the results of the study, a graph of the change in torque when the support is located during the operation of the drive was built. Based on the results of the work, the corresponding conclusion was made.
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Sinha, Nirmal K. "The Borehole Jack—Is It a Useful Arctic Tool?" Journal of Offshore Mechanics and Arctic Engineering 109, no. 4 (1987): 391–97. http://dx.doi.org/10.1115/1.3257037.
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As the working temperatures in ice are very close to its melting point, it behaves viscoelastically and experiences what is commonly known as high temperature embrittlement. Its mechanical properties are rate sensitive and analysis must include load and displacement history. Borehole jack tests can be improved by the use of an electrohydraulic pump in conjunction with simultaneous recording of pressure and diametral displacement as a function of time. These small but significant modifications in the test procedures permit analysis of the response of a borehole jack test system under operational conditions in the High Arctic in first-year and multi-year sea ice.
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Ibayeva, L. "TRANSMISSION MOUNTED ON A BALANCER DETERMINATION OF CHARACTERISTICS OF PUMP JACK." Sciences of Europe, no. 129 (November 27, 2023): 216–21. https://doi.org/10.5281/zenodo.10209572.
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The substantiation of the possibility of using in the transmission instead of pump jack a V-belt transmission of a chain transmission is considered, and the issue of non-stop operation of pumping units during floods and floods, when the water level rises to the electric motor and a forced shutdown of oil production occurs. In this case, an electric motor with a transmission, which includes a gearbox and a chain drive, is installed directly on the balancer, and the connecting rods are connected at one end to the cranks mounted on the driven shaft of the gearbox, and at the other end are pivotally fixed to the frame of the pumping unit. Formulas for determining the torque and forces acting on the mechanism are carried out, approximate graphs are given.
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Yarish, R. F., A. R. Garifullina, R. I. Garifullin, and A. N. Yakunin. "INVESTIGATION OF OPERATING MODES OF FREQUENCY-REGULATED ELECTRIC DRIVE OF PUMPJACK." Proceedings of the higher educational institutions. ENERGY SECTOR PROBLEMS 20, no. 11-12 (2019): 56–64. http://dx.doi.org/10.30724/1998-9903-2018-20-11-12-56-64.
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The analysis of the operating modes of the frequency-controlled electric drive of the pumpjack with the use of dynamometer cards, wattmeter diagrams and the mathematical model of the pump-jack, the effect of the shape of the dynamometer card on the operating mode of the electric motor of the pumpjack is determined. The ways of protection of the transistors in the frequency converter from voltage increase are considered at the transition of the electric motor to the regeneration.
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Li, Hai Ning, and Dai An Deng. "Research on Influence Factors of Hydraulic Support Moving Velocity in Coal Mining Based on AMESim." Advanced Materials Research 1014 (July 2014): 180–84. http://dx.doi.org/10.4028/www.scientific.net/amr.1014.180.
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In view of the high efficiency modernization coal demand, in this paper, the hydraulic support moving velocity influence factors were studied. Building simulation model of the thrust jack of hydraulic support with the simulation software AMESim, and run the simulation. Comparing the simulation results by setting different parameters value. It is concluded that the rated flow of pump station and hydraulic controlled check valve opening quantity will affect the speed of hydraulic support moving frame. This result provides reference for the optimal design of hydraulic support and improving the efficiency of coal mining. Key words: Moving velocity of hydraulic support; Rated flow; Hydraulic controlled check valve; AMESim 1 Tntroduction In the process of coal mining,the movement of hydraulic support needs in a timely manner with coal mining progresses, thrust jack plays a vital role for the movement of the hydraulic support. Therefore, it is very meaningful to research the influence factors of hydraulic support moving velocity With thrust control loop as the breakthrough point . 2 The working principle of the thrust control loop The movement of the hydraulic support and push the slide are achieved by thrust jack. Thrust jack is located in the middle part of the base of the hydraulic support, its end hinged with the base of the hydraulic support, the other end is connected with flexible scraper conveyor. When the hydraulic support moving, uninstall first, then the hydraulic controlled check valve make high pressure liquid into the piston rod cavity of thrust jack, the liquid in piston chamber flow back. At the same time, make thrust jack cylinder to move forward with the support of conveyor, thus, the whole hydraulic support is pulled to the coal wall, to complete the move. when pushing the slide, make high pressure liquid into the piston chamber , the liquid in piston rod cavity flow back, and, make the piston rod out with the support of hydraulic support. so,the conveyor is pushed to the coal wall,it is completed.
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Lee, Madeline, and Ryan Tinnea. "Controlling Corrosion in Concrete Aquarium Exhibits." Materials Performance 59, no. 3 (2020): 28–32. https://doi.org/10.5006/mp2020_59_3-28.
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A "jack-of-all-trades." Perhaps no profession better embodies this saying than a facilities maintenance manager at a public aquarium. Not only are they proficient in the arts of heating, ventilation, air conditioning, plumbing, electrical work, and routine troubleshooting, they also moonlight as chemists, balancing dissolved solid and oxygen content in the exhibits; mechanical engineers, controlling complex pump and piping systems; and biologists, ensuring nothing interferes with the exhibit plant and animal health. Many problems these maintenance managers must solve are unique to their facilities alone. With all the disciplines they juggle, it is no surprise one may be underestimated or misunderstood—corrosion.
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Malyar, Andriy, Bohdan Kaluzhnyi, and Roman Kvit. "Method of Selecting the Speed of Jack Pump Driving Motor Based on Reservoir Flow Rate." Energy engineering and control systems 4, no. 2 (2018): 87–92. http://dx.doi.org/10.23939/jeecs2018.02.087.
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Shishkin, Nickolai Dmitrievich, and Marina Aleksandrovna Marysheva. "Gas-driven downhole pumping unit for oil production from directional and horizontal wells." Oil and gas technologies and environmental safety 2023, no. 1 (2023): 37–42. http://dx.doi.org/10.24143/1812-9498-2023-1-37-42.
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The design of a gas-driven downhole pumping unit for oil production from directional and horizontal wells has been developed. The unit has no rod string, the slide and pneumatic jack are located in the tubing string. Using these units with a compressed associated gas as a working fluid will allow, unlike the hydraulic pumps, avoiding complex surface equipment for preparing the working fluid, maintenance of which is rather labour-consuming, and increasing the reliable operation of slides and downhole pumping units as a whole. In the course of experimental study of the parameters of the proposed installation it was shown on a laboratory bench showed that the fluid feed increases in direct proportion to the rate from 0.6 to 3.6 m/min. There has been obtained an empirical dependence to determine the flow of a borehole pump depending on its geometric parameters, plunger stroke length, stroke speed and gas content in the produced oil. According to the estimated parameters of the developed gas-driven unit, the supply can reach 386 m3/day, which is comparable to the supply of hydraulic units in use.
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Karunanidhi, Karthik, Mohanraj Manoharan, and Sathish Rajamanickam. "A Conceptual Model-based Design Approach for the Development of a New Hydraulic System Architecture for the UAV Class of Aircraft Application." Engineering Science 10, no. 1 (2025): 1–16. https://doi.org/10.11648/j.es.20251001.11.
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Advancements in aerospace system design are essential for improving efficiency, reducing weight, minimizing failures, and enhancing reliability while maintaining cost-effectiveness. This study presents a novel hydraulic system architecture for UAV-class aircraft, derived from conventional aircraft hydraulic designs. A conceptual modeling approach was employed to develop the system schematic, which was analyzed using LMS Amesim software to assess its performance under various conditions. The proposed system integrates a variable delivery piston hydraulic pump, an emergency accumulator, a bootstrap reservoir, and various hydraulic control valves. The design ensures optimal functionality while incorporating redundancy through an emergency landing gear extension mechanism. Hydraulic actuators control landing gear operations, with solenoid-operated selector valves regulating fluid flow based on operational needs. A shuttle valve allows automatic switching between the main hydraulic system and the emergency accumulator during system failures, ensuring reliability. LMS Amesim simulations validated key performance aspects, including pump pressure stabilization, accumulator charging behavior, landing gear actuation, and shuttle valve functionality. Results indicated stable pump operation at 206 bar, with emergency accumulator charging reaching 200 bar. The undercarriage system demonstrated smooth extension and retraction, with jack piston pressure transitions from 30 to 209 bar. The shuttle valve effectively switched between main and emergency hydraulic sources, enhancing system redundancy. Future improvements will focus on optimizing pump surge behavior, refining accumulator charging characteristics, integrating braking applications, and expanding hydraulic functionalities such as flap circuits. These enhancements will improve system robustness, efficiency, and fail-safe operation. This study demonstrates that conceptual modeling, combined with LMS Amesim simulations, is an effective approach for developing reliable hydraulic architectures for UAV-class aircraft, providing a strong foundation for future aerospace hydraulic advancements.
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Zheng, Yi, Jin Qing Jia, Li Li, and Shi Kuan You. "Bond-Slip Constitutive Behavior between Fiber-Reinforced Polymer and Masonry." Advanced Materials Research 446-449 (January 2012): 3165–70. http://dx.doi.org/10.4028/www.scientific.net/amr.446-449.3165.
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To study the bond behavior and the force transference of FRP plates adhered to masonry. In this paper, experiments of anchorage strength of FRP attached to masonry are done, a 100KN capacity hydraulic jack activated by a manual pump was used to load the specimen. The tensile strength was measured by using a loading transducer, and strain gauges were mounted directly onto the surface of the FRP composite to measure the strain during application of load. Besides the strain and bond stress development and distribution under every grade of loading were studied. Test results show that the maximum local bond stress is not influenced by the FRP bond length, instead it increases with masonry strength. At the same time, the local bond stress--slip curve is obtained. Based on the test results, two new bond stress-slip constitutive models between FRP and masonry were proposed and they turned out to be good matches to the experimental results, which indicate its valuable references for the corresponding codes and engineering applications.
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Stanghellini, Michael S., Jonathan R. Schultheis, and Gerald J. Holmes. "Adaptation and Market Potential of Jack o' lantern and Miniature Pumpkin Cultivars in Eastern North Carolina." HortTechnology 13, no. 3 (2003): 532–39. http://dx.doi.org/10.21273/horttech.13.3.0532.
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In 1998 and 1999, a total of 27 large-fruited and 15 miniature-fruited pumpkin (Cucurbita pepo) cultivars were evaluated for adaptation to eastern North Carolina grow- ing conditions. Test categories were yield (fruit number and weight); fruit characteristics (shape, rind and stem attributes); and susceptibility to edema (wart-like growths on fruit exterior), foliar diseases, preharvest and postharvest fruit decay, and viruses. Yields of large pumpkins ranged from over 3,200 fruit/acre (7,907 fruit/ha) for `SVT 4613367', `Autumn Gold', and `Gold Standard' to less than 1,000 fruit/acre (2,471 fruit/ha) for `Gold Rush' and `Progold 200'. For miniature pumpkins, over 33,000 fruit/acre (81,542 fruit/ha) were produced by `Touch of Autumn', `Lil' Pump- ke-mon', and `HMX 5682', whereas `Mystic' and `Progold 100' produced less than 7,000 fruit/acre (17,297 fruit/ha). `Gold Rush', `Howden', and `Progold 510' (large), and `EXT 4612297', `Lil' Goblin', and `Lil' Ironsides' (miniature) appeared the most susceptible to foliar diseases. Preharvest fruit decay ranged from 0% for `Howden' and `EXT 4612297' to over 20% for `Lil' Goblin', `Jumping Jack', `Peek-A-Boo', and `Tom Fox'. Virus incidence on fruit and foliage was low on virus-resistant cultivars ('SVT 4613367' and `EXT 4612297'), and ranged from 4% to 74% for nontransgenic cultivars. Virus incidence and/or severity on foliage and fruit were not related. `Early Autumn' (large) and `Touch of Autumn' (miniature) were the most prone to edema. `Aspen' and `Magic Lantern' (large) and `Baby Pam', `Lil' Goblin', and `Spooktacular' (miniature) were the most susceptible to postharvest fruit decay. Fruit characteristics are discussed in relation to marketability and possible consumer appeal to pumpkins.
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Gao, Tenghua, Menglin Li, Shunxin Zhang, et al. "The Application and Optimization of a New Tunnel Ventilation Method for the Control Room of Electric Submersible Pump Systems on Jack-Up Offshore Platforms." Buildings 15, no. 3 (2025): 325. https://doi.org/10.3390/buildings15030325.
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This study focused on the novel ventilation solution used in the control room of an electric submersible pump on a jack-up offshore platform, with the core objective of exploring the advantages of tunnel ventilation over the traditional ceiling-mounted ventilation system. At the beginning of the research, a three-dimensional physical model of the room’s air conditioning and ventilation system was constructed using Rhino 7 software. Subsequently, the computational fluid dynamics software Airpak 3.0 was employed to conduct detailed thermodynamic calculations on the model. Based on this, the study meticulously compared the performance of the two ventilation systems from multiple perspectives: one aspect examined the airflow and temperature distribution through temperature contour maps, velocity vector maps, and airflow streamlines; another focused on the comfort level of personnel, as reflected in the key indicators of the predicted mean vote and predicted percentage dissatisfied. The results demonstrated that tunnel ventilation is highly effective in reducing the indoor temperature and significantly improving personnel comfort. Further optimization analysis revealed that, under specific inlet conditions, namely when the inlet velocity reaches 1.16 m/s and the inlet temperature is 17 °C, the most ideal ventilation effect can be achieved, thereby fully and effectively meeting human thermal comfort requirements. Overall, the findings of this study not only provide a novel solution for the environmental control system design of offshore platforms but also lay a solid scientific foundation for continued exploration in related fields, offering a reliable reference for future research.
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Haque, MA, R. Begum, AZ Shibly, MM Sultana, and A. Khatun. "Influence of Jackfruit Pulp on the Quality and Shelf Life of Jackfruit Cake." Journal of Environmental Science and Natural Resources 8, no. 1 (2015): 59–64. http://dx.doi.org/10.3329/jesnr.v8i1.24672.
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This study was designed to develop cakes incorporating jack-fruit pulp. The seed free jackfruit bulbs blend were used at the level of 10%, 20%, 30% and 40% to prepare jackfruit cake The physical and chemical properties of cakes were analyzed and compared with plane cake (without jack-fruit pulp).The cake containing 10% jack-fruit pulp was best among the samples on the basis of rust and crumb colour and texture of the cakes..The flavours of the cake containing 20% jack-fruit pulp were better than other cakes. The statistical analysis of organoleptic test response of sensory attributes revealed that colour, flavour, taste, texture and overall acceptability werehigher in the cakes containing 10% and 20% jackfruitpulp than normal cake.Shelf life of jack-fruitcakes were decreased with the increased level of substitution of jackfruit pulp during seven day storage on the basis of microbial count.Cake containing 10% jack-fruit showed acceptable physical characteristics, sensory attributes and microbial load.J. Environ. Sci. & Natural Resources, 8(1): 59-64 2015
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Ciusa, Maria Laura, Robert L. Marshall, Vito Ricci, Jack W. Stone, and Laura J. V. Piddock. "Absence, loss-of-function, or inhibition of Escherichia coli AcrB does not increase expression of other efflux pump genes supporting the discovery of AcrB inhibitors as antibiotic adjuvants." Journal of Antimicrobial Chemotherapy 77, no. 3 (2021): 633–40. http://dx.doi.org/10.1093/jac/dkab452.
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Abstract Objectives To determine whether expression of efflux pumps and antibiotic susceptibility are altered in Escherichia coli in response to efflux inhibition. Methods The promoter regions of nine efflux pump genes (acrAB, acrD, acrEF, emrAB, macAB, cusCFBA, mdtK, mdtABC, mdfA) were fused to gfp in pMW82 and fluorescence from each reporter construct was used as a measure of the transcriptional response to conditions in which AcrB was inhibited, absent or made non-functional. Expression was also determined by RT-qPCR. Drug susceptibility of efflux pump mutants with missense mutations known or predicted to cause loss of function of the encoded efflux pump was investigated. Results Data from the GFP reporter constructs revealed that no increased expression of the tested efflux pump genes was observed when AcrB was absent, made non-functional, or inhibited by an efflux pump inhibitor/competitive substrate, such as PAβN or chlorpromazine. This was confirmed by RT-qPCR for PAβN and chlorpromazine; however, a small but significant increase in macB gene expression was seen when acrB is deleted. Efflux inhibitors only synergized with antibiotics in the presence of a functional AcrB. When AcrB was absent or non-functional, there was no impact on MICs when other efflux pumps were also made non-functional. Conclusions Absence, loss-of-function, or inhibition of E. coli AcrB did not significantly increase expression of other efflux pump genes, which suggests there is no compensatory mechanism to overcome efflux inhibition and supports the discovery of inhibitors of AcrB as antibiotic adjuvants.
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Casalone, Enrico, Tiziano Vignolini, Laura Braconi, et al. "Characterization of substituted piperazines able to reverse MDR in Escherichia coli strains overexpressing resistance-nodulation-cell division (RND) efflux pumps." Journal of Antimicrobial Chemotherapy 77, no. 2 (2021): 413–24. http://dx.doi.org/10.1093/jac/dkab388.
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Abstract Background MDR in bacteria is threatening to public health. Overexpression of efflux pumps is an important cause of MDR. The co-administration of antimicrobial drugs and efflux pump inhibitors (EPIs) is a promising approach to address the problem of MDR. Objectives To identify new putative EPIs and to characterize their mechanisms of action. Methods The effects of four selected piperazine derivatives on resistance-nodulation-cell division (RND) pumps was evaluated in Escherichia coli strains overexpressing or not expressing RND pumps by assays aimed at evaluating antibiotic potentiation, membrane functionality, ethidium bromide accumulation and AcrB expression. The cytotoxicity of selected piperazines towards primary cultures of human dermal fibroblasts was also investigated. Results Four molecules enhanced levofloxacin activity against strains overexpressing RND efflux pumps (AcrAB-TolC and AcrEF-TolC), but not against RND pump-deficient strains. They had little effects on membrane potential. Molecule 4 decreased, whereas the other three increased, membrane permeability compared with untreated control cells. The four molecules showed differences in the specificity of interaction with RND efflux pumps, by inactivating the transport of one or more antibiotics, and in the levels of ethidium bromide accumulation and of acrB expression inhibition. Conclusions Piperazine derivatives are good candidates as inhibitors of RND efflux pumps. They decreased the activity of RND pumps by mixed mechanisms of action. Small structural differences among the molecules can be critical in defining their behaviour.
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Carpenter, Chris. "Fiber-Reinforced Thermoplastic Sucker Rods Provide Artificial Lift Efficiencies." Journal of Petroleum Technology 76, no. 10 (2024): 85–87. http://dx.doi.org/10.2118/1024-0085-jpt.
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_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper IPTC 23949, “Fiber-Reinforced Thermoplastic Sucker Rods Providing High-Strength, Lightweight, Low-Cost, and Environmentally Responsible Artificial Lift Efficiencies,” by Jeff Saponja, SPE, Oilify, and Corbin Coyes, SPE, and Michael Conner, SPE, Q2 Artificial Lift Services. The paper has not been peer reviewed. Copyright 2024 International Petroleum Technology Conference. _ The complete paper focuses on the development of fiber-reinforced thermoplastic (FRTP) sucker rods, highlighting their potential advantages and challenges, for rod pumping (in general) and for offering an earlier transition from electrical submersible pump (ESP) pumping or gas lifting to reliable deep high-rate rod pumping. A unique feature of an FRTP composite rod is its remarkably high shear failure resistance compared with that of a thermoset composite rod. A high shear-failure resistance means the rods have compressional loading tolerance and that an entire sucker rod string could be comprised of FRTP sucker rods. Introduction Sucker rods made from steel are relatively heavy. Extensive well-specific designs require tapering of rod strings to optimize the overall sucker rod string weight relative to the strength and fatigue requirements and consideration of the dynamic loadings from accelerations and decelerations of the rods and fluids, frictional effects, and structural or power limitations of the pump jack or unit at surface. Steels suffer from corrosion risks. Corrosion, which rapidly can accelerate fatigue failure, often is the root cause of sucker rod failure. Fiber-reinforced composites (i.e., fibers surrounded by or wetted by a resin matrix) have gained considerable popularity because they can be tailored to have outstanding mechanical, thermal, and physical properties, and have superior material mechanical properties to metal. The fatigue behavior of composite materials and structures is complex because composites fail by a series of, or collection of, damage mechanisms, including fiber breakage, matrix cracking, fiber/matrix debonding, delamination, and the effect of shear-induced damage on cracks. Cracking can be slowed somewhat if the reinforced fibers are of high stiffness. Composite materials can offer a lower environmental footprint over their entire life cycle. They can require less energy to manufacture, thereby reducing CO2 emissions. A high strength/weight ratio offers less energy consumption during operational use, further reducing CO2 emissions. Composite materials can be recycled and reused. Composite sucker rods, in the form of thermoset fiberglass sucker rods, have offered a high strength/weight ratio with greater corrosion tolerance, but they are too stretchy from a low glass fiber tensile modulus of elasticity for deep high-rate rod pumping and when a high production-rate decline is likely. This limitation results in a large bottomhole pump-stroke variability as operating conditions change. Such rods have low tolerance to compressional and impact loads, forcing a larger proportion of a sucker string to remain as steel. They are also more costly than steel rods. For sucker rod pumping, an ideal composite rod should tolerate compressional loads and feature high impact resistance and high fatigue endurance with an ability to limit or control crack formation. A composite material that potentially offers these important sucker rod properties is FRTP.
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Kang, Kyu-Young, Shu Y. Zhang, and Shawn D. Mansfield. "The effects of initial spacing on wood density, fibre and pulp properties in jack pine (Pinus banksiana Lamb.)." Holzforschung 58, no. 5 (2004): 455–63. http://dx.doi.org/10.1515/hf.2004.069.
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Abstract Relationships between basic tree and wood properties, and species, seed source, geographic location, site conditions and management decisions are very complex. The objective of this study was to quantify the effects of forest management practices on wood density, fibre and pulp properties in jack pine, one of the most important commercial species in Northern America. A better understanding of the relationship between initial spacing and wood and end-product quality should help define improved forest management strategies required to produce quality wood and products in the future. On the basis of the oldest jack pine initial spacing trial established in 1941 by the USDA Forest Service, this study examined the impact of four different initial spacing trials on tree growth, wood density, fibre and pulp properties of jack pine. The results clearly show that initial stand spacing has a significant effect on all of these properties, and thus it is possible to improve yield and wood and pulp fibre properties of jack pine through stand density regulation. Additionally, a positive effect of pre-commercial thinning on fibre properties was also demonstrated. As a consequence of these results, basic prescription information for decision-making in the establishment of jack pine plantations with desirable pulp properties can be elucidated.
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Emaime, Jimmy Uwanta, Esiet Udo Itoro, Nyakno Willie Itoro, and Effiong Akpakpan Aniekan. "Phytochemical screening, proximate and vitamin composition of Jack fruit (Artocarpus Heterophyllus) pulp and seed." World Journal of Advanced Research and Reviews 22, no. 1 (2024): 1500–1506. https://doi.org/10.5281/zenodo.14225748.
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The potential health benefits of plant are determined by the level of phytochemicals, proximate, minerals and vitamin composition of the plant material. The study was carried out to determine the phytochemical composition, proximate and vitamin content of Artocarpus heterophyllus pulp and seeds. The results revealed that Artocarpus heterophyllus is rich in phytochemicals such as Saponins, Alkaloid, Cardiac Glycoside, Phlobatannins, Terpenes, Steroids and Deoxy-Sugar. Proximate composition analysis indicated that the pulp has higher moisture, protein and lipid content, while crude fibre and carbohydrate were higher in the seed. The fruit pulp contained a greater percentage of vitamins A and C compared to the seeds. These phytochemicals, proximate composition, and vitamins offer numerous health benefits, suggesting that the consumption of jack fruit pulp and seeds may help in alleviating various health challenges.
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Zhu, J. Y., and Gary C. Myers. "Kraft pulp from budworm-infested Jack pine." Holzforschung 60, no. 4 (2006): 383–88. http://dx.doi.org/10.1515/hf.2006.060.
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Abstract This study evaluated the quality of kraft pulp from budworm-infested jack pine. The logs were classified as merchantable live, suspect, or merchantable dead. Raw materials were evaluated through visual inspection, analysis of the chemical composition, SilviScan measurement of the density, and measurement of the tracheid length. Unbleached pulps were then refined using a laboratory disk refiner. The mechanical and optical properties of handsheets made from the refined pulps were evaluated. Although budworm galleries may affect the physical integrity of the wood, they have no effect on pulp quality. Blue stain did not affect the handsheet brightness. The results indicate that merchantable dead jack pine trees are acceptable for kraft pulp production, with equivalent pulp yield.
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Lucaßen, Kai, Carina Müller, Julia Wille, et al. "Prevalence of RND efflux pump regulator variants associated with tigecycline resistance in carbapenem-resistant Acinetobacter baumannii from a worldwide survey." Journal of Antimicrobial Chemotherapy 76, no. 7 (2021): 1724–30. http://dx.doi.org/10.1093/jac/dkab079.
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Abstract Objectives To determine the most common tigecycline resistance mechanisms in carbapenem-resistant Acinetobacter baumannii isolates obtained during the global Tigecycline Evaluation Surveillance Trial (TEST). Methods Tigecycline MICs were determined by broth microdilution. WGS was used to screen for the previously identified tigecycline resistance mechanisms, as well as mutations in resistance-nodulation-cell division (RND)-type efflux pump regulators. Results From a total 313 isolates, 113 genetically unique tigecycline-resistant isolates were analysed. The most frequent and worldwide distributed mechanism associated with tigecycline resistance was disruption of adeN, which encodes the repressor of the RND efflux pump AdeIJK, either by IS elements or nucleotide deletions causing premature stop codons. However, mutations leading to amino acid substitutions and disruption by IS elements within the two-component regulatory system adeRS, which regulates expression of the AdeABC efflux pump, correlate with higher tigecycline MICs, but these were found less frequently and were mainly restricted to Southern European countries. Furthermore, an altered version of tviB was identified in several tigecycline-resistant isolates that did not have putative resistance mutations within RND-type regulators. The resistance determinants tet(A) and tet(X), as well as resistance mutations in putative resistance determinants trm, plsC, rrf, msbA and genes encoding 30S ribosomal proteins, were not identified in any isolate. Conclusions The most prevalent tigecycline resistance mechanisms were caused by alterations in the regulators of RND-type efflux pumps. These data provide the basis for further characterization of regulator alterations and their contribution to increased efflux and tigecycline resistance, and also should be taken into account in drug discovery programmes to overcome the contribution of efflux pumps.
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Law, Kwei-Nam, and Jacques L. Valade. "Status of the utilization of jack pine (Pinusbanksiana) in the pulp and paper industry." Canadian Journal of Forest Research 24, no. 10 (1994): 2078–84. http://dx.doi.org/10.1139/x94-266.
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Although jack pine (Pinusbanksiana Lamb.), which represents 20% of the total softwood volume, is one of the most abundant commercial softwood species in Canada, its rate of utilization in pulping is surprisingly low. This paper reviews the literature concerning the physical and chemical properties as well as the pulping characteristics of this species by mechanical, thermomechanical, chemithermomechanical, chemimechanical, and chemical processes to better understand its potential use in papermaking. The objective is to identify the problems related to the use of jack pine so that solutions might be sought to promote its usage. Some recommendations are put forth concerning future research.
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Boyce, Alan S. "Progressing cavity pumps – a jack of all trades." World Pumps 2005, no. 466 (2005): 18–21. http://dx.doi.org/10.1016/s0262-1762(05)70633-7.
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Abdol Jani, Wan Nur Fazlina, Noor Hidayu Abdul Rani, Nor Fadilah Mohamad, and Sharifah Iziuna Sayed Jamaludin. "Hydrometallurgical Recovery of Copper from Computer-Printed Circuit Boards." E3S Web of Conferences 599 (2024): 04006. https://doi.org/10.1051/e3sconf/202459904006.
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Modern electronic devices contain up to 60 different metals, leading to a growing interest in exploring secondary sources, particularly electronic waste (e-waste), to address potential shortages. This study focused on extracting copper (Cu) and gold (Au) from three different sources of computer-printed circuit boards (PCBs): board, USB jack, and capacitor. Aqua regia, a mixture of 68% concentrated nitric acid and 37% concentrated hydrochloric acid in a 1:3 ratio (HNO3=1:3), was used as a leachant under various conditions, including different types of e-waste components, leaching times, and surface areas. Acidic leaching with a 1% (w/v) e-waste pulp density resulted in higher Cu extraction from PCB board waste compared to USB jack and capacitor waste. The optimal recovery of Cu achieved was 2207 mg/L after 20 minutes of leaching, using a particle size of 10 mm, at 100°C, 150 rpm, and a pulp density of 1% (w/v). The dissolution of Au was only traceable in the capacitor and USB jack with significantly lower quantities of 0.4 and 3.2 mg/L, respectively. Additionally, the electrowinning process managed to recover Cu with just 31.6% purity after one hour of electrolysis. In conclusion, this study demonstrates the feasibility of recovering valuable metals from e-waste through acid leaching, without the need for additional chemical treatments.
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Qiu, Yunyan, Long Zhang, Cristian Pezzato, et al. "A Molecular Dual Pump." Journal of the American Chemical Society 141, no. 44 (2019): 17472–76. http://dx.doi.org/10.1021/jacs.9b08927.
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Wang, Sheldon, Lynn Rowlan, Dennis Cook, Carson Conray, Ross King, and Carrie Anne Taylor. "Dynamics of pump jacks with theories and experiments." Upstream Oil and Gas Technology 11 (September 2023): 100097. http://dx.doi.org/10.1016/j.upstre.2023.100097.
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Jacobsson, Susanne, Daniel Golparian, Nicole Scangarella-Oman, and Magnus Unemo. "In vitro activity of the novel triazaacenaphthylene gepotidacin (GSK2140944) against MDR Neisseria gonorrhoeae." Journal of Antimicrobial Chemotherapy 73, no. 8 (2018): 2072–77. http://dx.doi.org/10.1093/jac/dky162.
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Abstract Objectives Increased antimicrobial resistance surveillance and new effective antimicrobials are crucial to maintain treatable gonorrhoea. We examined the in vitro activity of gepotidacin, a novel triazaacenaphthylene, and the effect of efflux pump inactivation on clinical Neisseria gonorrhoeae isolates and international reference strains (n = 252) and compared gepotidacin with antimicrobials currently or previously recommended for gonorrhoea treatment. Methods MICs (mg/L) were determined by agar dilution (gepotidacin) or by Etest (seven other antimicrobials). The gyrA and parC genes were sequenced and the impact of inactivation of the MtrCDE, MacAB and NorM efflux pumps on gepotidacin MICs was examined. Results Gepotidacin showed potent in vitro activity against all gonococcal isolates (n = 252; MIC ≤4 mg/L). The modal MIC, MIC50, MIC90 and MIC range of gepotidacin were 0.5, 0.5, 1 and 0.032–4 mg/L, respectively. Inactivation of the MtrCDE efflux pump, but not MacAB or NorM, decreased the gepotidacin MICs for most strains. No significant cross-resistance between gepotidacin and any other antimicrobials, including the fluoroquinolone ciprofloxacin, was identified. However, the ParC D86N mutation (possibly together with additional antimicrobial resistance mutation), which is associated with fluoroquinolone resistance, was associated with increased gepotidacin MICs. Conclusions Gepotidacin demonstrated high in vitro activity against gonococcal strains, indicating that gepotidacin could potentially be an effective option for gonorrhoea treatment, particularly in a dual antimicrobial therapy regimen and for patients with resistance or allergy to extended-spectrum cephalosporins. Nevertheless, elucidating in vitro and in vivo resistance emergence and mechanisms in detail, together with further gonorrhoea clinical studies, ideally also including chlamydia and Mycoplasma genitalium are essential.
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Emaime Jimmy Uwanta, Itoro Eshiet Udo, Itoro Nyakno Willie, and Aniekan Effiong Akpakpan. "Phytochemical screening, proximate and vitamin composition of Jack fruit (Artocarpus Heterophyllus) pulp and seed." World Journal of Advanced Research and Reviews 22, no. 1 (2024): 1500–1506. http://dx.doi.org/10.30574/wjarr.2024.22.1.1027.
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The potential health benefits of plant are determined by the level of phytochemicals, proximate, minerals and vitamin composition of the plant material. The study was carried out to determine the phytochemical composition, proximate and vitamin content of Artocarpus heterophyllus pulp and seeds. The results revealed that Artocarpus heterophyllus is rich in phytochemicals such as Saponins, Alkaloid, Cardiac Glycoside, Phlobatannins, Terpenes, Steroids and Deoxy-Sugar. Proximate composition analysis indicated that the pulp has higher moisture, protein and lipid content, while crude fibre and carbohydrate were higher in the seed. The fruit pulp contained a greater percentage of vitamins A and C compared to the seeds. These phytochemicals, proximate composition, and vitamins offer numerous health benefits, suggesting that the consumption of jack fruit pulp and seeds may help in alleviating various health challenges.
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Canton, Martina, Jessica Groppi, Lorenzo Casimiro, et al. "Second-Generation Light-Fueled Supramolecular Pump." Journal of the American Chemical Society 143, no. 29 (2021): 10890–94. http://dx.doi.org/10.1021/jacs.1c06027.
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Praski Alzrigat, Lisa, Douglas L. Huseby, Gerrit Brandis, and Diarmaid Hughes. "Resistance/fitness trade-off is a barrier to the evolution of MarR inactivation mutants in Escherichia coli." Journal of Antimicrobial Chemotherapy 76, no. 1 (2020): 77–83. http://dx.doi.org/10.1093/jac/dkaa417.
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Abstract Background Mutations that inactivate MarR reduce susceptibility to ciprofloxacin and competitive growth fitness in Escherichia coli. Both phenotypes are caused by overexpression of the MarA regulon, which includes the AcrAB-TolC drug efflux pump. Objectives We asked whether compensatory evolution could reduce the fitness cost of MarR-inactivating mutations without affecting resistance to ciprofloxacin. Methods The cost of overexpressing the AcrAB-TolC efflux pump was measured independently of MarA overexpression. Experimental evolution of MarR-inactive strains was used to select mutants with increased fitness. The acquired mutations were identified and their effects on drug susceptibility were measured. Results Overexpression of the AcrAB-TolC efflux pump was found not to contribute to the fitness cost of MarA regulon overexpression. Fitness-compensatory mutations were selected in marA and lon. The mutations reduced the level of MarA protein thus reducing expression of the MarA regulon. They restored growth fitness but also reduced resistance to ciprofloxacin. Conclusions The fitness cost caused by overexpression of the MarA regulon has multiple contributing factors. Experimental evolution did not identify any single pump-independent cost factor. Instead, efficient fitness compensation occurred only by mechanisms that reduce MarA concentration, which simultaneously reduce the drug resistance phenotype. This resistance/fitness trade-off is a barrier to the successful spread of MarR inactivation mutations in clinical isolates where growth fitness is essential.
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Cai, Kang, Yi Shi, Guo-Wei Zhuang, et al. "Molecular-Pump-Enabled Synthesis of a Daisy Chain Polymer." Journal of the American Chemical Society 142, no. 23 (2020): 10308–13. http://dx.doi.org/10.1021/jacs.0c04029.
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Merta, Miroslav. "How the treatment of gastrointestinal tract disorders may be infl uenced by the kidneys." Gastroenterologie a hepatologie 75, no. 5 (2021): 445–50. http://dx.doi.org/10.48095/ccgh2021445.
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Summary: The treatment of gastrointestinal tract (GIT) diseases may, under specific conditions, be significantly influenced by the kidneys or by kidney disorders. One of the potential scenarios of such interaction is the concurrent involvement of the kidneys and the GIT organs within one disorder, another option being the negative impact of impaired renal function on the prognosis of the GIT disease and, finally, the need for an adequate choice and dose adjustment of renally eliminated medication to avoid nephrotoxicity. Renal impairment may occur as an adverse effect of the treatment of the GIT condition and may limit further therapy. In this context we have recently focused on the following clinical situations: the development of acute kidney injury during treatment with proton pump inhibitors, renal complications of inflammatory bowel disease management and the development of acute phosphate nephropathy due to the use phosphate containing laxatives. An early identification of the mechanisms leading to renal injury can prevent the development of irreversible renal lesions and facilitate an efficient treatment of the GIT. Key words: treatment of gastrointestinal tract disorders – acute kidney injury – proton pump inhibitors – renal complications of inflammatory bowel disease – acute phosphate nephropathy
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Kurniawan, Anri, Tri Wahyu Saputra, and Anugerah Ramadan. "SISTEM FERTIGASI RAIN PIPE OTOMATIS PADA MAIN NURSERY KELAPA SAWIT (Elaeis guineensis Jacq) BERBASIS MIKROKONTROLER ARDUINO UNO." Jurnal Teknik Pertanian Lampung (Journal of Agricultural Engineering) 9, no. 3 (2020): 184. http://dx.doi.org/10.23960/jtep-l.v9i3.184-190.
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This research conducted to designed, implemented, and tested an automatic rain pipe fertigation system using temperature and soil moisture sensors. The system applied to three irrigation treatments, namely manual fertilization, semi-manual fertilization, and automatic fertigation. The automatic fertigation actuator setting point is at temperature of ≥ 31 ° C and humidity of ≤ 60% to turn on the water pump and nutrient pump then the water pump will shut down when the temperature value of 25 °C and humidity of ≥ 80%. The results showed a significant difference in the use of irrigation water based on variance test results with an error value of 5%. The use of water from automatic fertigation is 12.770 ml or 65.9% more efficient than manual irrigation with the same growth in plant height. The height of oil palm plants in the main nursery with automatic fertigation is higher on days 7 to 12. Automatic fertilization requires a fertilizer of 1.8 tons per ha, less than manual fertilization which reaches 3 tons per ha. Keywords: fertigation, microcontroller, oil palm, sensors, soil moisture
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Stavri, Michael, Laura J. V. Piddock, and Simon Gibbons. "Bacterial efflux pump inhibitors from natural sources." Journal of Antimicrobial Chemotherapy 59, no. 6 (2006): 1247–60. http://dx.doi.org/10.1093/jac/dkl460.
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da Silva, Lucas Yure Santos, Cicera Laura Roque Paulo, Talysson Felismino Moura та ін. "Antibacterial Activity of the Essential Oil of Piper tuberculatum Jacq. Fruits against Multidrug-Resistant Strains: Inhibition of Efflux Pumps and β-Lactamase". Plants 12, № 12 (2023): 2377. http://dx.doi.org/10.3390/plants12122377.
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Antimicrobial resistance has become a growing public health concern in recent decades, demanding a search for new effective treatments. Therefore, this study aimed to elucidate the phytochemical composition and evaluate the antibacterial activity of the essential oil obtained from the fruits of Piper tuberculatum Jacq. (EOPT) against strains carrying different mechanisms of antibiotic resistance. Phytochemical analysis was performed using gas chromatography–mass spectrometry (GC/MS). The antibacterial activity of EOPT and its ability to inhibit antibiotic resistance was evaluated through the broth microdilution method. The GC-MS analysis identified 99.59% of the constituents, with β-pinene (31.51%), α-pinene (28.38%), and β-cis-ocimene (20.22%) being identified as major constituents. The minimum inhibitory concentration (MIC) of EOPT was determined to assess its antibacterial activity against multidrug-resistant strains of Staphylococcus aureus (IS-58, 1199B, K2068, and K4100). The compound showed a MIC of ≥ 1024 μg/mL, suggesting a lack of intrinsic antibacterial activity. However, when the EOPT was associated with antibiotics and EtBr, a significant decrease in antibiotic resistance was observed, indicating the modulation of efflux pump activity. This evidence was corroborated with the observation of increased fluorescent light emission by the bacterial strains, indicating the involvement of the NorA and MepA efflux pumps. Additionally, the significant potentiation of ampicillin activity against the S. aureus strain K4414 suggests the β-lactamase inhibitory activity of EOPT. These results suggest that the essential oil from P. tuberculatum fruits has antibiotic-enhancing properties, with a mechanism involving the inhibition of efflux pumps and β-lactamase in MDR S. aureus strains. These findings provide new perspectives on the potential use of EOPT against antibiotic resistance and highlight the importance of Piper species as sources of bioactive compounds with promising therapeutic activities against MDR bacteria. Nevertheless, further preclinical (in vivo) studies remain necessary to confirm these in vitro-observed results.
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Lu, Hsu-Feng, Yu-Chieh Tsai, Li-Hua Li, Yi-Tsung Lin, and Tsuey-Ching Yang. "Role of AzoR, a LysR-type transcriptional regulator, in SmeVWX pump-mediated antibiotic resistance in Stenotrophomonas maltophilia." Journal of Antimicrobial Chemotherapy 76, no. 9 (2021): 2285–93. http://dx.doi.org/10.1093/jac/dkab203.
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Abstract Background The SmeVWX efflux pump of Stenotrophomonas maltophilia contributes to menadione (MD) tolerance and resistance to chloramphenicol, quinolones and tetracycline. The components of the SmeVWX efflux pump are encoded by a five-gene operon, smeU1VWU2X. We have previously demonstrated that the smeU1VWU2X operon is intrinsically unexpressed and inducibly expressed by MD via a SoxR- and SmeRv-involved regulatory circuit in S. maltophilia KJ. We also inferred that there should be other regulator(s) involved in MD-mediated smeU1VWU2X expression in addition to SoxR and SmeRv. Objectives To identify novel regulator(s) involved in the regulation of MD-mediated smeU1VWU2X expression and elucidate the regulatory circuit. Methods A possible regulator candidate involved in the regulation of MD-mediated smeU1VWU2X expression was identified by a homologue search using the helix-turn-helix domain of SmeRv as a query. Gene expression was assessed using the promoter-xylE transcriptional fusion assay and quantitative RT–PCR. The impact of the regulator on SmeVWX pump-mediated functions was investigated via mutant construction and functional tests (antibiotic susceptibility and MD tolerance). Results AzoR (Smlt3089), a LysR-type transcriptional regulator, was investigated. In unstressed logarithmically grown cells, AzoR was abundantly expressed and functioned as a repressor, inhibiting the expression of the smeU1VWU2X operon. MD challenge attenuated azoR expression, thus derepressing the expression of the smeU1VWU2X operon in S. maltophilia KJ. AzoR down-regulation-mediated smeU1VWU2X expression was observed in quinolone-resistant and SmeVWX-overexpressing S. maltophilia clinical isolates. Conclusions AzoR negatively regulates the expression of the smeU1VWU2X operon and SmeVWX pump-mediated antibiotic resistance in S. maltophilia.
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Guo, Qing-Hui, Yunyan Qiu, Xinyi Kuang, et al. "Artificial Molecular Pump Operating in Response to Electricity and Light." Journal of the American Chemical Society 142, no. 34 (2020): 14443–49. http://dx.doi.org/10.1021/jacs.0c06663.
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Parent-Michaud, Maxime, Philippe J. Dufresne, Eric Fournier, et al. "Prevalence and mechanisms of azole resistance in clinical isolates of Aspergillus section Fumigati species in a Canadian tertiary care centre, 2000 to 2013." Journal of Antimicrobial Chemotherapy 75, no. 4 (2019): 849–58. http://dx.doi.org/10.1093/jac/dkz534.
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Abstract Objectives Azole resistance among Aspergillus fumigatus isolates is a growing concern worldwide. Induction of mutations during azole therapy, environment-acquired mutations caused by azole fungicides and intrinsic resistance of cryptic Fumigati species all contribute to the burden of resistance. However, there is a lack of data in Canada on this emerging threat. Methods To gain insights into the magnitude and mechanisms of resistance, a 14 year collection of Aspergillus section Fumigati comprising 999 isolates from 807 patients at a Montreal hospital was screened for azole resistance, and resistance mechanisms were investigated with the combined use of genome sequencing, 3D modelling and phenotypic efflux pump assays. Results Overall azole resistance was low (4/807 patients; 0.5%). A single azole-resistant A. fumigatus sensu stricto strain, isolated from a patient with pulmonary aspergillosis, displayed efflux-pump-mediated resistance. Three patients were colonized or infected with azole-resistant cryptic Fumigati species (one Aspergillus thermomutatus, one Aspergillus lentulus and one Aspergillus turcosus). Evidence is presented that azole resistance is efflux-pump-mediated in the A. turcosus isolate, but not in the A. lentulus and A. thermomutatus isolates. Conclusions Azole resistance is rare in our geographic area and currently driven by cryptic Fumigati species. Continued surveillance of emergence of resistance is warranted.
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Butcher, Joshua D., Charles P. Laubscher, and Johannes C. Coetzee. "A Study of Oxygenation Techniques and the Chlorophyll Responses of Pelargonium tomentosum Grown in Deep Water Culture Hydroponics." HortScience 52, no. 7 (2017): 952–57. http://dx.doi.org/10.21273/hortsci11707-16.
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Pelargonium tomentosum Jacq.; the peppermint-scented pelargonium, is an herbaceous groundcover indigenous to the Western Cape of South Africa. Volatile oils are produced by this plant, which are used in the fragrance industry. Studies on other Pelargonium species have shown chlorophyll content may affect the yield of essential oils. This study was carried out to investigate the viability of growing P. tomentosum in deep water culture (DWC) hydroponics and how best to aerate/oxygenate the nutrient solution to increase the chlorophyll content within leaves. The experiment was conducted over a period of 74 days, 16 different methods of oxygenation were applied to 9 replicates. The control had passive aeration; the treatments were made up of air-pumps, vortex oxygenators, and the application of hydrogen peroxide at various frequency intervals; these were combined with each other and run as separate oxygenation methods. The measurement of the chlorophyll content of plant leaves has been established to be an accurate way of establishing vigor, health, and levels of stress. It was found that the combination of high-frequency application (every third day) of hydrogen peroxide, vortex oxygenation, and air-pump injection (both operational for 24 hours/day) which formed treatment 11 (APVHa), yielded the highest production of chlorophyll within all the replicates differing significantly (P ≤ 0.001) from the control and other treatments.
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Solanki, Shailendra, Rakesh Bhardwaj, Ramesh Vasudeva, Sushil Chourey, and Sunil Archak. "Biochemical Composition of Pulp and Seed of Wild Jack (Artocarpus hirsutus Lam.) Fruit." Plant Foods for Human Nutrition 75, no. 4 (2020): 659–60. http://dx.doi.org/10.1007/s11130-020-00849-5.
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Sanchez, P. "The efflux pump inhibitor Phe-Arg-beta-naphthylamide does not abolish the activity of the Stenotrophomonas maltophilia SmeDEF multidrug efflux pump." Journal of Antimicrobial Chemotherapy 51, no. 4 (2003): 1042–45. http://dx.doi.org/10.1093/jac/dkg181.
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Feng, Yuanning, Marco Ovalle, James S. W. Seale, et al. "Molecular Pumps and Motors." Journal of the American Chemical Society 143, no. 15 (2021): 5569–91. http://dx.doi.org/10.1021/jacs.0c13388.
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Vincent, Manon, and Isabelle Duchesne. "Modeling flexural properties in white spruce (Picea glauca) and jack pine (Pinus banksiana) plantation trees." Canadian Journal of Forest Research 44, no. 1 (2014): 82–91. http://dx.doi.org/10.1139/cjfr-2013-0312.
Full textAbstract:
Mixed models combining random coefficient effect and covariance patterns were used to investigate mechanical property variations in jack pine (Pinus banksiana Lamb.) and white spruce (Picea glauca (Moench) Voss) trees. Modulus of elasticity (MOE) and modulus of rupture (MOR) were measured by conducting three-point bending tests on small defect-free samples selected from different radial positions and at a height of 2.5 m above ground within the stems. The objective of the paper was to build statistical predictive models describing the radial variations in stems for wood mechanical properties using easily measurable explanatory variables that are typically available in the wood manufacturing industry: distance from pith, tree height and diameter, and spacing. The explanatory variables integrated into the models explained MOE adequately, whereas MOR appeared harder to predict with only these variables and at this resolution. For white spruce, the best mixed-effects models explained 80% and 61% of the variation in MOE and MOR, respectively. For jack pine, it was 51% and 33% for the same response variables. These results are a step toward models that could be used in sawing simulation software designed to estimate the internal properties of sawlogs and, as a result, better predict lumber and pulp chip quality.