Energy Supplementation Research Articles

Nutritional Recommendations for Pregnant Women Receiving Dialysis: A Scoping Review

Pregnancy in the dialysing population is an infrequent but increasing event. There is a lack of contemporary guidance regarding the nutritional management of this complex patient group. The aim of this scoping review was to identify, evaluate and summarise the evidence base describing nutritional recommendations for pregnant women receiving dialysis. A systematic search strategy of four databases and the grey literature was conducted. Eligible publications contained reference to recommendations regarding nutrition, supplements, breastfeeding, dietary patterns, and/or weight recommendations for pregnant dialysing women. A total of 136 eligible records were included for synthesis including 66 case reports/case series, 46 reviews, 15 book chapters, 5 editorials, and 4 consensus guidelines/position papers. Recommendations regarding energy, protein, dietary patterns, weight, and vitamin and mineral supplementation were common. However, significant discrepancy across these recommendations was evident. There were limited recommendations regarding other nutrients and breastfeeding. A summary of nutritional recommendations to guide clinical practice was constructed. Pregnancy planning, pre-conception dietetic counselling, interprofessional education, and the guidance synthesised in this review could be utilised by clinicians to improve clinical management and optimise outcomes in these patients. Future research should explore the experiences and perspectives of pregnant dialysing women, investigate nutrient losses during intensive dialysis, and evaluate postpartum follow-up.

Displacement-based design procedure for the seismic retrofit of existing buildings with self-centering dissipative braces

Existing framed buildings, especially those designed according to outdated seismic codes, often offer inadequate seismic protection levels due to material degradation, low amount of reinforcement and poor construction details. Among the possible retrofit strategies, elasto-plastic dissipative braces (EPDBs) can be installed to provide supplemental stiffness and energy dissipation in the main resisting frame. Since they are based on the plastic deformation of sacrificial steel components, EPDBs are inherently affected by scarce recentering capability, i.e., presence of residual deformation at the end of the mainshock that could impair their effectiveness for aftershock events. As demonstrated in recent seismic sequences, there might be not enough time to restore (e.g., though hydraulic actuators and a reaction frame) the undeformed configuration of the structure before a subsequent shock. This issue can be overcome through self-centering dissipative braces (SCDBs), i.e., braces equipped with dampers characterized by a “flag-shaped” hysteretic behavior, which inherently facilitates the immediate re-centering of the frame. Despite this evident benefit, there is still lack of practical design procedures for the seismic retrofit of buildings through SCDBs. To fill this gap, a direct displacement-based design procedure for SCDBs tailored to building frames is here conceived and illustrated. The proposed method aims at achieving simultaneously two performance requirements: (i) a target maximum roof displacement under the ultimate-limit-state seismic event; (ii) the absence of significant residual inter-storey drifts at the end of the shaking. The implementation of the procedure is described by two applications to a steel and to a reinforced concrete case-study building. Nonlinear time-history analyses are carried out to prove the effectiveness of the proposed method, along with a comparison of the seismic performance offered by SCDBs versus traditional EPDBs implemented in the same case-study buildings.

Mechanical insights into jawbone characteristics under chronic kidney disease: A comprehensive nanoindentation approach

The mechanical properties of the jawbone play a critical role in determining the successful integration of dental prostheses. Chronic kidney disease (CKD) has been identified to abnormally accelerate bone turnover rates. However, the impact of CKD on the mechanical characteristics of the jawbone has not been extensively studied. This study sought to evaluate the time-dependent viscoelastic behaviors of rat jawbones, particularly in the scenarios both with and without CKD. We hypothesized that CKD might compromise the bone's innate toughening mechanisms, potentially owing to the time-dependent viscoelasticity of the bone matrix proteins. The maxillary and mandibular bones of Wistar rats were subjected to nanoindentation and Raman micro-spectroscopy. Load-hold-displacement curves from the cortical regions were obtained via nanoindentation and were mathematically characterized using a suitable viscoelastic constitutive model. Raman micro-spectroscopy was employed to identify nuanced vibrational changes in local molecular structures induced by CKD. The time course of indenter penetration onto cortical bones during the holding stage (creep behavior) can be mathematically represented by a series arrangement of the Kelvin–Voigt bodies. This configuration dictates the overall viscoelastic response observed during nanoindentation tests. The CKD model exhibited a reduced extent of viscoelastic contributions, especially during the initial ramp loading phase in both the maxillary and mandibular cortical bones. The generalized Kelvin–Voigt model comprises 2 K–Voigt elements that signify an immediate short retardation time (τ1) and a subsequent prolonged retardation time (τ2), respectively. Notably, the mandibular CKD model led to an increase in the delayed τ2 alongside an increase in non-enzymatic collagen cross-linking. These suggest that, over time, CKD diminishes the bone's capability for supplementary energy absorption and dimensional recovery, thus heightening their susceptibility to fractures.

HOLŞTAYN SÜT İNEKLERİNDE DOĞUM SONRASI SIVI-ELEKTROLİT VE ENERJİ KATKISININ FERTİLİTE PARAMETRELERİ ÜZERİNE ETKİSİ

In this study, the effect of orally given fluid-electrolyte and energy supplementation immediately after the delivery on some metabolic and fertility parameters was investigated. Holstein dairy cows which were housed in a private dairy company under same management and feeding programs divided into two groups as experiment (n=70) and control (n=75). Cows in the experiment group were treated by orally given 5 kg fluid-electrolyte and energy supplementation dissolved in 20 litres lukewarm water for consecutive three days, whereas the control group received only 20 litres of lukewarm water. The ear tag numbers of all cows used in the study were recorded and monitored until next delivery. It was determined that the concentrations of βHBA in the experiment group was lower than those measured in the control group (p0.05). It was seen that the synchronization rate was lower in the experiment group than those detected in the control group (p0.05). On the other hand, the service number per pregnancy was displayed a higher incidence in the control group as compared to the experiment group (p

Energy- and yield-based performance evaluation of a phase change material–integrated single-span double-layered with a thermal screen greenhouse

Greenhouse technology emerged to ensure the optimum yield of the host crop —a prerequisite to achieving Sustainable Development Goals 7 and 2. To achieve this, supplemental energy is needed under extreme weather conditions at about half the operational cost. Researchers have focused and succeeded in reducing the energy demand using numerical methods with little focus on the impact of these methods on crop yield. A novel greenhouse system—phase change material–integrated single-span double-layered strawberry greenhouse with a thermal screen—is introduced herein. Furthermore, how the energy management method affects the yield of the host crop is explored. Moreover, the energy-saving potential and yield enhancement achieved by integrating PCMs and other passive thermal-management systems in a specific agricultural setting is investigated. TRNSYS 18 software is used to evaluate the effect of three passive variables on two performance indices. The passive variables are location: Daegu (DG), Seoul, and Jeju Island (JE); orientation: 90° (E-W), 45° (NE-SW), and 0° (N-S); and PCM type: “No-fill”, water, and Paraffin (ParC13–C24). The effect of thermal screen control was also studied on the localized optium configuration. Finally, economic analysis was conducted to ascertain the most sustainable configuration. The performance indices are the heating demand and strawberry yield. The results show that the location, orientation, and PCM usage inside the greenhouse greatly affect the greenhouse’s heating demand and crop yield. The configuration selected must be in such a way that the indoor nighttime temperature does not exceed 2 °C above the minimum nighttime optimum value of the host crop.

A retrospective cohort study on the correlation between early energy management and bronchopulmonary dysplasia in premature infants

Objective: To investigate the correlation between early energy supplement and bronchopulmonary dysplasia (BPD) in very preterm and very low birth weight infants. Methods: A retrospective cohort study design was used. A total of 939 preterm infants who were admitted to the Department of Neonatology of the West China Second Hospital of Sichuan University within 24 h after birth from January 2019 to December 2021 were enrolled in the study. They were born with a gestational age of <32 weeks and (or) a birth weight of <1 500 g. Of them, 250 preterm infants who developed BPD were enrolled in the BPD group, and each of them was matched to a preterm infant who did not develop BPD (matched for gestational age and birth weight) in the order of priority after calculating propensity score. Their total energy, enteral energy, parenteral energy, total fluid intake and energy per unit of fluid per week were collected within the first 2 weeks of life. The independent sample t-test or Mann Whitney U test was used for continuous variables, and the χ2 test for between-group comparisons of categorical variables. Univariate and multivariate Logistic regression analyses were used to explore the association between total energy and total fluid and BPD incidence, respectively. The dose-response relationship between parenteral energy and BPD was investigated by a generalized additive model, and the threshold effect of parenteral energy on BPD used a two-piecewise linear regression model. Results: The gestational age was (28.4±1.9) weeks in the BPD group and (29.5±1.3) weeks in the control group; the birth weight was (1 107±258) g in the BPD group and (1 324±261) g in the control group; and there were 140 males (56.0%) and 131 males (52.4%) in each group, respectively. An increase in energy per unit of fluid in the second week of life was associated with a reduced risk of BPD (OR=0.32, 95%CI 0.12-0.84, P=0.021), and an increase in total energy in the second week of life was also associated with a reduced risk of BPD, with total energy of >418-502 kJ/(kg·d) was significantly lower than when total energy was ≤334 kJ/(kg·d) (OR=0.15, 95%CI 0.03-0.85, P=0.033). There was no association between the average total fluid intake and BPD incidence (both P>0.05) in the first and second week. The increase in the proportion of parenteral energy to total energy in the second week of life was associated with an increased incidence of BPD (OR=8.45, 95%CI 2.14-33.32, P=0.003); specifically, the risk of BPD significantly increased when the parenteral energy was ≥305 kJ/(kg·d) (OR=1.02, 95%CI 1.01-1.03, P=0.003). Conclusions: Maintaining a high total energy supply in the early postnatal period in preterm infants may reduce the risk of BPD, but continued reliance on high parenteral energy to meet total energy requirements increases the risk of BPD, so enteral feeds should be initiated as early as possible and maximized as tolerated.

Photo-assisted electrocatalysis of NiO/CeO2 heterojunction for efficient oxygen evolution reaction

In recent years, photo-assisted electrocatalysis has attracted significant interest in the field of electrolytic hydrogen production. By integrating electrical and optical energy, supplementary energy is harnessed for the electrocatalytic process, which offers an efficient strategy to enhance the performance of oxygen evolution reaction (OER). Herein, the heterojunction NiO/CeO2 composite nanostructures supported by nickel foam (represented as NiO/CeO2@NF) was selected as the photo-assisted electrocatalyst, through the mutual synergy of voltage and light to improve the catalytic activity of OER in electrolytic water. Under light irradiation, the NiO component undergoes photoexcited to produce photogenerated electrons that move towards the CeO2 component, stimulating the generation and accumulation of more holes accelerating the formation of Ni (III) to improve the reaction efficiency with electrons, thereby boosting the enhancement of OER activity. The results demonstrate that the overpotential corresponding to NiO/CeO2@NF in non-irradiation at 10 mA cm−2 current density was 280 mV, and the NiO/CeO2@NF in light irradiation displays robust OER activity, with lower over-potentials 260 mV at 10 mA cm−2, which 20 mV lower than in non-irradiation. Moreover, NiO/CeO2@NF in light irradiation exhibits high catalytic activity and durability for OER in an alkaline electrolyte, delivering 100 mA cm−2 at 320 mV and outperforming RuO2 under high current densities.

Novel Design of Multi-DOF Motor Position Estimation Based on Wireless Power Transmission Modeling

In this paper, a multi-coil wireless power transmission model is presented. The model is applied to the multi-degree-of-freedom (multi-DOF) motor rotor position detection system. The wireless power transmission (WPT) system is evenly distributed on the upper part of the rotor, and the receiving coil is placed on the rotor shaft. When the motor rotor rotates along the three motion states of pitch, spin and tilt, the receiving coil and multi-transmit coil will produce angle deviation. The precise mutual inductance estimation method can be used to obtain the rotor position quickly and avoid the complicated finite element calculation. The system can not only realize the pose estimation of the multi-DOF motor, but also provide flexible energy supplement for the manipulator. The WPT position measurement method is used for PID control of multi-DOF motor, and it is compared with the micro-electro-mechanical-system (MEMS) attitude measurement method. The mechanical sliding measurement method of the encoder is taken as a reference. The results show that the position detection method of WPT has high accuracy, and the estimation error is less than 2%.

The Energy Requirement for Supplemental Greenhouse Lighting Can Be Reduced by Considering 'Excess' Light from the Previous Day.

The sunlight greenhouse crops receive varies and is often insufficient for consistent year-round growth in greenhouses. Supplemental lighting is commonly applied in winter, but this practice has a significant energy cost, accounting for 10-30% of operating expenses and impacting greenhouse profitability. Greenhouse lights are traditionally adjusted based on sunlight intensity to meet crops' daily light requirements. However, if plants can withstand lower daily light integrals (DLI) after a sunny day without reducing the growth, there is potential to reduce the energy required for supplemental lighting and increase the profit. To determine whether excess light received one day can be 'carried over' to the next, we grew oakleaf lettuce (Lactuca sativa 'Green Salad Bowl' and 'Red Salad Bowl') under six lighting regimes inside a vertical farm. Plants in all treatments received an average DLI of 15 mol·m-2·d-1, but DLIs alternated from day-to-day (15/15, 17.5/12.5, 20/10, 22.5/7.5, 25/5, and 27.5/2.5 mol·m-2·d-1), resulting in DLI fluctuations from 0 to 25 mol·m-2·d-1. Plants had similar leaf area (~800 cm2/plant) and dry weight (~1.8 g/plant) when grown with DLI fluctuations from 0 to 15 mol·m-2·d-1, while higher DLI fluctuation reduced growth. To confirm this DLI "carrying-over" effect on plants grown under sunlight with supplemental light, we conducted a second study in a greenhouse with 'Green Salad Bowl' lettuce. In this study, plants were grown with five different DLI fluctuations (15/15, 16.75/13.25, 18.5/11.5, 20.25/9.75, and 22/8 mol·m-2·d-1), ranging from 0 to 14 mol·m-2·d-1, while maintaining an average DLI of 15 mol·m-2·d-1 in all the treatments. We observed similar leaf area (~750 cm2/plant) and dry weight (~1.8 g/plant) in lettuce plants grown with DLI fluctuations from 0 to 10.5 mol·m-2·d-1. Higher DLI fluctuations reduced growth. Hence, carrying excess light from a sunny to an overcast day is possible within limits. Our study concluded that the DLI requirement can be reduced by approximately 5.25 mol·m-2·d-1 on the day following a sunny day. By analyzing historical weather data from five US locations, we quantified the potential annual energy savings from incorporating this 'carrying-over DLI' concept. This approach resulted in annual energy savings of approximately 75-190 MWh/ha in greenhouse lettuce production. Such reductions in supplemental lighting energy will enhance the profitability and sustainability of the greenhouse industry.

Do catadromous thinlip grey mullet benefit from shifting to freshwater? A perspective from fatty acid signature analysis

To investigate the potential benefits of the catadromous thinlip grey mullet (Chelon ramada Risso, 1827) migration to freshwater, the total lipid content and fatty acid (FA) profile of female’s muscle and gonads caught in both the estuary and river were analyzed. The freshwater contingent presented a higher body condition, greater muscle gross energy, and larger gonads with higher lipid reserves. These animals showed a muscle profile rich in C16:1n-7 and lower LC-PUFA that contrast with the higher relative amount of C18:1n-9, n-3 FA, and unsaturated LC-PUFA, such as C18 and C20 FA found in the estuarine contingent. The gonads of both contingents showed a constant and high relative amount of polyunsaturated FAs (PUFA, 37%). However, in terms of essential fatty acids (EFAs), the estuarine contingent had a higher relative amount of C18:2n-6, C20:4n-6, C20:5n-3, and C22:6n-3. On the other hand, the freshwater contingent showed a higher relative amount of n-3 FA precursors, namely C18:3n-3, and a still low relative amount of C22:6n-3. This suggests a mismatch between the metabolic omega-3 pathway and the physiological maturity stages, similar to a phenomenon of dormancy. In this sense, not all these individuals may reproduce annually, and the later stages of gonad development will require supplementary energy derived from feeding at the estuary. Thus, freshwater migration may promote a reproductive strategy enabling adults to take advantage of the warm and food-rich summer/autumn period, adjust spawning and juvenile appearance, and reduce the population’s exposure to habitat changes and/or stochastic events.

Optimal allocation of energy storage capacity for hydro-wind-solar multi-energy renewable energy system with nested multiple time scales

Multi-energy supplemental renewable energy system with high proportion of wind-solar power generation is an effective way of “carbon neutral”, but the randomness and volatility of wind-solar power generation seriously affects the safe and stable operation of power grid. With the development of energy storage technology, this problem can be effectively solved by configuring energy storage, but how to reasonably configure energy storage is one of the key issues due to the expensive energy storage. To this end, a multi-timescale nested energy storage capacity optimization model for multi-energy supplemental renewable energy system with pumped storage hydro plant based on a three-battery group control operation strategy is proposed. First, the electrochemical energy storage is added to the supplemental renewable energy system containing hydro-wind-solar to form a hybrid energy storage system with pumped storage hydro units, and its group control strategy and charging/discharging coordinated operation are investigated. Then, a double-layer energy storage capacity optimization model nested in multiple time scales is developed. The inner layer optimizes hydropower and pumped storage output to smooth out the more fluctuating wind power output with large time scales. The outer layer optimizes energy storage taking into account factors such as output deviation, cost, attenuation, and dynamic prediction life to smooth out the less volatile and smaller time-scale wind power. Finally, simulation demonstrates that the proposed model can make full use of the flexible regulation capability of pumped storage hydro units and the fast response capability of batteries to maximize the fluctuation of the supplemental system into the grid, and further reduce the peaking pressure of the receiving end of the grid. In addition, the superiority of the proposed three-battery grouping strategy over the traditional battery control method in terms of saving investment cost and mitigating battery life loss is also verified. The advantages of the strategy in terms of carbon reduction and cleaner production are also illustrated in quantifiable terms.

Milk fatty acid profile of cows grazing elephant grass BRS Kurumi pasture with and without energy supplementation

This study evaluated the effects of energy supplementation on the intake and milk fatty acid composition of cows grazing BRS Kurumi elephant grass pasture during the rainy season. Two treatments (with and without supplementation) were evaluated using a switchback design with six Holstein × Gyr dairy cows after the peak of lactation. The average milk yield, body weight, and days in milk of the cows at the beginning of the study were 18.0±2.89 kg day−1, 560±66 kg, and 99±12, respectively. The evaluations were performed over three grazing cycles, with adaptation periods of 14 days and six days of sampling. In the energy supplementation treatment, each cow received 3 kg day−1 of ground corn (as-fed basis), with 2 kg day−1 at the morning milking and 1 kg day−1 at the afternoon milking. The ground corn presented 87.5% dry matter, 7.3% crude protein, 5.1% ether extract, and 85% of total digestible nutrients. The cows supplemented with ground corn consumed more oleic (+567%) and linoleic (+88%) acids. Unsupplemented cows consumed 26% more α-linolenic acid and produced milk with more oleic (+10%), vaccenic (+23%), and rumenic (+21%) acids, and less (−7%) pro-atherogenic fatty acids (lauric + myristic + palmitic acids). Milk fat from unsupplemented cows showed better nutritional quality, with lower atherogenicity and thrombogenicity indices and a higher hypo/hypercholesterolemic fatty acid ratio.

The use of branched horizontal wells at the Zhanazhol field to increase oil recovery

The research presents an analysis and experiment on horizontal wells of the Zhanazhol field, an analysis of the operation of horizontal wells is carried out. The analysis of the factors affecting the efficiency of oil production by horizontal wells is carried out, experimental and industrial methods of operation are proposed for further implementation of horizontal well technology. The design of the construction of branched horizontal wells has been carried out. The purpose of this work is to substantiate the feasibility of switching to fundamentally new development systems using horizontal wells to increase the flow rate of liquid hydrocarbons using the example of the Zhanazhol field. The results of pilot tests of drilling branched horizontal wells to increase oil recovery at the Zhanazhol field are summarized. At the Zhanazhol field, the maximum capacity of oil reservoirs reaches about 190 m. The average capacity of oil–saturated reservoirs is about 3 m. There are intervals of impermeable interlayers in the productive formation. The thickness of most impermeable layers varies within 5 m. An impenetrable layer with a thickness of about 10 m is spreading widely. This affects the nutrition and energy supplementation of oil reservoirs, resulting in a rapid decrease in oil production and reservoir pressure. For example, the average daily flow rate of oil with a 15 mm fitting is more than 150 tons, but the current flow rate of oil with a 7 mm fitting is 52 tons (horizontal well No. 2407). The technology of drilling branched horizontal wells in certain geological conditions allows: to obtain initial flow rates 10 times higher than the flow rates of conventional wells with an increase in the cost of drilling only 1.5 - 2 times; to ensure accumulated production over 10-15 years of operation 10 times higher at the cost of extracted oil 3-5 times lower than for neighboring conventional wells; to increase the total oil recovery from productive formations by 20-30 percent; to thin the well development grids.

Service equilibrium of urban transportation energy supply station based on cooperative game

PurposeAs of December 2022, there were 119,000 gas stations, 10,800 gas stations and 4,488,000 charging piles nationwide, while the number of vehicles reached 312 million, including 11.49 million new energy vehicles. The imbalance between transportation energy supply and energy replenishment demand leads to crowded queues of vehicles at some stations and idle resources in others. How to reduce the phenomenon of large queues and improve the utilization rate of idle resources is the key to alleviating the imbalance between supply and demand.Design/methodology/approachTherefore, from the perspective of spatio-temporal equilibrium of urban transportation energy supply stations, multi-energy supply station cooperation is established in view of the phenomenon of large spatio-temporal differences among different energy supply stations, and corresponding inducing strategies are adopted for energy supplement vehicles in the road network, so that part of queued users go to energy supply stations with fewer vehicles, so as to balance the supply and demand of transportation energy in the region. On this basis, the income distribution of urban transportation energy supply station is discussed.FindingsThe total revenue after the cooperation was 13,095, an increase of 22.9%. Secondly, in terms of distribution rationality, three impact factors are selected and Shapley correction value is used to distribute the total income. Compared with independent operation, both sites have a certain degree of increase.Originality/valueTraffic congestion at energy supply stations is closely related to the number, location and number of vehicles at energy supply stations. Therefore, using a cooperative approach of energy trading cannot solve the queuing problem. In addition, there are a few research results on the equalization of energy supply station services considering time-of-use pricing. However, these studies do not consider the vehicular grooming at congested stations. As far as the authors know, there are no relevant research results in the research on the service equilibrium of energy supply stations based on cooperative games.

Nutritional interventions for preventing and treating pressure ulcers.

Nutritional interventions for preventing and treating pressure ulcers.

Maternal prepartum supplementation of protein and energy and body condition score modulated the performance of Bos indicus-influenced cow-calf pairs

Retrospective analyses were performed on a dataset of 1188 fall-calving, Brangus cow-calf pairs. Analyses 1 sorted cows according to their initial body condition score (BCS < 5 vs. ≥ 5) and whether they received (SUP) or not (NOSUP) prepartum supplementation of protein and energy. Analyses 2 sorted cows according to their calving BCS (BCS < 5 or ≥ 5) and BCS change from calving until the start of the breeding season (lost, maintained, or gained). Cows were not estrus synchronized and were assigned to natural breeding for 90 days. Prepartum supplementation increased (P = 0.04) pregnancy percentage in cows with initial BCS < 5 but not (P = 0.20) with initial BCS ≥ 5. Calf weaning weight was greatest (P ≤ 0.04) for calves born from SUP cows with an initial BCS ≥ 5 and did not differ (P ≥ 0.56) among all remaining groups. Among cows with calving BCS < 5, pregnancy percentage were less (P = 0.05) for cows that lost vs. maintained/gained BCS. Postpartum BCS change did not (P ≥ 0.16) impact pregnancy percentage of cows calving at BCS ≥ 5. Calf weaning weight increased (P < 0.01) for cows calving with BCS ≥ 5 vs. < 5 and was not impacted (P = 0.47) by postpartum BCS change. Therefore, precalving supplementation improved reproduction of cows with BCS below optimal and weaning weight of calves born from cows with BCS above optimal, whereas calving BCS was the major factor affecting postpartum BCS change and cow reproductive performance.

The effects of feeding sows at onset of farrowing supplemental energy (blend of carbohydrates and glycerol) on farrowing kinetics and piglet vitality

Delivering piglets is one of the most energy-demanding activities sows undergo in their lifetime. Sows can have myometrial contractions from 2 to 12 h before the first piglet is expelled as well as a nest-building behavior. Thus, when the first piglet is delivered, the female has already used part of her energy supply. When the sow gets exhausted due to lack of energy, the farrowing process can be interrupted, causing damage to the viability and vitality of the piglets. In the present study, we evaluated the effects of feeding sows an energy supplement at the onset of farrowing on farrowing kinetics and piglet vitality. The energy supplement consisted of a blend of carbohydrates and glycerol which provides 439 kJ of metabolizable energy per kg of metabolic weight. A total of 180 sows were used. At the onset of farrowing, sows were assigned to one of the following treatments: sows that were not supplied energy at the onset of farrowing, serving as controls (CON, n = 85); sows fed the energy supplement at the onset of farrowing (ESP, n = 95). Farrowing kinetics, blood glucose concentration, and piglet vitality were recorded for each sow. Blood glucose concentration was assessed by puncturing the auricular vein and using a portable glucometer at four different time points: after the birth of the 1st piglet (T0), and at 20 (T20), 40 (T40), 80 (T80), and 180 (T180) min after the birth of the 1st piglet. The vitality of the 1st, 6th, 12th, 17th, and 20th piglet born was evaluated using the Apgar score. Piglet birth weight and average colostrum intake were measured. The farrowing duration was 20 min shorter (P < 0.05) for ESP sows in comparison with CON sows. Sows from ESP treatment had higher (P ≤ 0.05) blood glucose concentration at T20 and T40 compared to the CON sows. The inter-piglet birth interval was shortened (P < 0.05) by 14 min between the 1st and 2nd piglet for the ESP treatment. The 17th and 20th piglets born from ESP sows had higher (P < 0.05) Apgar score compared to piglets of the same birth order from CON sows. Colostrum intake was higher (P < 0.01) for piglets born from ESP sows. Litter growth performance did not differ (P > 0.05). In conclusion, feeding a blend of carbohydrates and glycerol as an energy supplement for farrowing sows improved farrowing kinetics and piglet vitality score.

Advancing PetroChina’s Development Strategies for Low-Permeability Oil Reservoirs

Based on PetroChina’s status and situation of low-permeability oil reservoir development, this paper analyzes the key common issues in the production capacity construction of new oilfields, the stable production of old oilfields, and enhanced oil recovery, and, in connection with the progress made in major development technologies and the results of major development tests for low-permeability oil reservoirs in recent years, puts forward the technical countermeasures and development directions. For optimizing the development of low-grade reserves, a comprehensive life-cycle development plan is essential, alongside experimenting with gas injection and energy supplementation in new fields. Addressing challenges in reservoir classification, multidisciplinary sweet spot prediction, and displacement–imbibition processes can significantly boost well productivity. In fine water flooding reservoirs, the focus should shift to resolving key technological challenges like dynamic heterogeneity characterization, and functional and nano-intelligent water flooding. For EOR, accelerating the application of carbon capture, utilization, and storage (CCUS) advancements, along with air injection thermal miscible flooding, and middle-phase microemulsion flooding, is crucial. This approach aims to substantially enhance recovery and establish a new model of integrated secondary and tertiary recovery methods.

A technique for enhancing tight oil recovery by multi-field reconstruction and combined displacement and imbibition

A seepage-geomechanical coupled embedded fracture flow model has been established for multi-field coupled simulation in tight oil reservoirs, revealing the patterns of change in pressure field, seepage field, and stress field after long-term water injection in tight oil reservoirs. Based on this, a technique for enhanced oil recovery (EOR) combining multi-field reconstruction and combination of displacement and imbibition in tight oil reservoirs has been proposed. The study shows that after long-term water flooding for tight oil development, the pressure diffusion range is limited, making it difficult to establish an effective displacement system. The variation in geostress exhibits diversity, with the change in horizontal minimum principal stress being greater than that in horizontal maximum principal stress, and the variation around the injection wells being more significant than that around the production wells. The deflection of geostress direction around injection wells is also large. The technology for EOR through multi-field reconstruction and combination of displacement and imbibition employs water injection wells converted to production and large-scale fracturing techniques to restructure the artificial fracture network system. Through a full lifecycle energy replenishment method of pre-fracturing energy supplementation, energy increase during fracturing, well soaking for energy storage, and combination of displacement and imbibition, it effectively addresses the issue of easy channeling of the injection medium and difficult energy replenishment after large-scale fracturing. By intensifying the imbibition effect through the coordination of multiple wells, it reconstructs the combined system of displacement and imbibition under a complex fracture network, transitioning from avoiding fractures to utilizing them, thereby improving microscopic sweep and oil displacement efficiencies. Field application in Block Yuan 284 of the Huaqing Oilfield in the Ordos Basin has demonstrated that this technology increases the recovery factor by 12 percentage points, enabling large scale and efficient development of tight oil.

Streptococcal arginine deiminase system defences macrophage bactericidal effect mediated by XRE family protein XtrSs

ABSTRACT The arginine deiminase system (ADS) has been identified in various bacteria and functions to supplement energy production and enhance biological adaptability. The current understanding of the regulatory mechanism of ADS and its effect on bacterial pathogenesis is still limited. Here, we found that the XRE family transcriptional regulator XtrSs negatively affected Streptococcus suis virulence and significantly repressed ADS transcription when the bacteria were incubated in blood. Electrophoretic mobility shift (EMSA) and lacZ fusion assays further showed that XtrSs directly bind to the promoter of ArgR, an acknowledged positive regulator of bacterial ADS, to repress ArgR transcription. Moreover, we provided compelling evidence that S. suis could utilize arginine via ADS to adapt to acid stress, while ΔxtrSs enhanced this acid resistance by upregulating the ADS operon. Moreover, whole ADS-knockout S. suis increased arginine and antimicrobial NO in the infected macrophage cells, decreased intracellular survival, and even caused significant attenuation of bacterial virulence in a mouse infection model, while ΔxtrSs consistently presented the opposite results. Our experiments identified a novel ADS regulatory mechanism in S. suis, whereby XtrSs regulated ADS to modulate NO content in macrophages, promoting S. suis intracellular survival. Meanwhile, our findings provide a new perspective on how Streptococci evade the host’s innate immune system.