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Dietary nutrient manipulation (e.g. protein fractions) could lower the environmental footprints of ruminants, especially reactive nitrogen (N). This study investigated the impacts of dietary soluble protein (SP) levels with decreased crude protein (CP) on intestinal N absorption, hindgut N metabolism, fecal microbiota and metabolites, and their linkage with N metabolism phenotype. Thirty-two male Hu sheep, with an age of six months and an initial BW of 40.37 ± 1.18 kg, were randomly assigned to four dietary groups. The control diet (CON), aligning with NRC standards, maintained a CP content of 16.7% on a dry matter basis. Conversely, the experimental diets (LPA, LPB, and LPC) featured a 10% reduction in CP compared with CON, accompanied by SP adjustments to 21.2%, 25.9%, and 29.4% of CP, respectively. Our results showed that low-protein diets led to significant reductions in the concentrations of plasma creatinine, ammonia, urea N, and fecal total short-chain fatty acids (SCFA) (P

Abstract Background Compost-bedded pack barns (CBP) are getting huge attention as an alternative housing system for dairy cows due to their beneficial impact on animal welfare. Effective microorganisms (EM) inoculums are believed to enhance compost quality, improve soil structure and benefit the environment. However, little information is available on the impact of incubation with external EM combinations on the barn environment, compost quality and microbial diversity in CBP. This experiment was carried out to investigate the effect of inoculating different combinations of EM [Lactobacillus plantarum (L), Compound Bacillus (B) and Saccharomyces cerevisiae (S)] on compost quality and microbial communities of CBP products, as well as the relationship with the heifers’ barn environment. CBP barns were subjected to the following four treatments: CON with no EM inoculum, LB/LS/LBS were Incubated with weight ratios of 1:2 (L: B), 1:2 (L: S), 1:1:1 (L: B: S), respectively. Results The EM inoculation (LB, LS, LBS) reduced the concentration of respirable particulate matter (PM10 and PM2.5) in the CBP, and decreased the serum total protein and total cholesterol levels in heifers. Notably, LBS achieved the highest content of high-density lipoprotein compared to other treatments. Microbiome results revealed that EM inoculation reduced the bacterial abundance (Chao1 index) and fungal diversity (Shannon & Simpson indexes), while increasing the relative abundance of various bacterial genera (Pseudomonas, Paracoccus, Aequorivita) and fungi (Pestalotiopsis), which are associated with cellulose decomposition that ultimately resulted in accelerating organic matter degradation and humification. Furthermore, high nutrient elements (TK&TP) and low mycotoxin content were obtained with EM inoculation, with LBS showing a particularly pronounced effect. Meanwhile, LBS contributed to a decline in the proportion of fungal pathogen categories but also led to an increase in fungal saprotroph categories. Conclusion Generally, EM inoculation positively impacted compost product quality as organic fertilizer and barn environment by modifying the abundance of cellulolytic bacteria and fungi, while inhibiting the reproduction of pathogenic microbes, especially co-supplementing with L, B and S achieved an amplifying effect.

Abstract Domesticated herbivores are an important agricultural resource that play a critical role in global food security, particularly as they can adapt to varied environments, including marginal lands. An understanding of the molecular basis of their biology would contribute to better management and sustainable production. Thus, we conducted transcriptome sequencing of 100 to 105 tissues from two females of each of seven species of herbivore (cattle, sheep, goats, sika deer, horses, donkeys, and rabbits) including two breeds of sheep. The quality of raw and trimmed reads was assessed in terms of base quality, GC content, duplication sequence rate, overrepresented k-mers, and quality score distribution with FastQC. The high-quality filtered RNA-seq raw reads were deposited in a public database which provides approximately 54 billion high-quality paired-end sequencing reads in total, with an average mapping rate of ~93.92%. Transcriptome databases represent valuable resources that can be used to study patterns of gene expression, and pathways that are related to key biological processes, including important economic traits in herbivores.

Distributed energy resources (DER) are integrated into a microgrid through dc-dc power electronic converters. The bidirectional dc-dc converter regulates charging and discharging operations of ESS. Model predictive control (MPC), is a high-performance control technique for these converters, but it is limited in robustness to parameter mismatch, model uncertainties and sensor measurement noise. Therefore, in this paper, an improved hybrid cascade-parallel extended state observer (CP-ESO) is proposed, for model-free predictive control, to guarantee both robustness to parameter/model uncertainties and measurement noise suppression. A novel structurally-adaptive ESO scheme is also proposed to improve the disturbance rejection of CP-ESO during transient response. These results are supported by analysis and design guidelines for the selection of optimal sub-frequencies. Experimental results, for a bidirectional dc-dc boost converter, validate the effectiveness of the proposed methods against model uncertainties, external disturbances from variable input voltage and load, as well as measurement noise.

This article presents the use of model predictive control (MPC) in multilevel inverters for some applications, such as, first, wind generation and, second, photovoltaics, showing that the particular restrictions of each of them can be very easily included in the control algorithm, which is an important advantage of this technique. Another application is in modular multilevel cascaded converters, where it is demonstrated that MPC can operate with very few calculations and fixed switching frequency. The second part of this article is dedicated to comparing MPC with linear control and pulsewidth modulation for multilevel inverters. The main comparison criteria are the switching losses, the distortion in the load current, and the number of commutations. The main conclusion is that MPC is a competitive alternative to linear control for application in multilevel inverters.

This case describes the benefits of perioperative chemo-immunotherapy for advanced gastric cancer and incomplete pyloric obstruction, supplemented with nutritional support. Early parenteral nutrition to stabilize nutritional status and mitigate nutrition impact symptoms, and in addition, throughout the chemo-immunotherapy perioperative period also maintained oral nutrition support and a tailored dietary plan. Above nutritional support maintained the patient’s physical condition during immunotherapy. Eventually, this combination therapy plan leads to a partial response. On the other hand, a combination of therapies that focus more on immune checkpoint inhibitor may be able to mitigate the side effects of chemotherapy. Such findings may yield novel prospects for patients with advanced gastric cancer and incomplete pyloric obstruction, enabling them to achieve better outcomes.

Abstract Background This work aimed to study natural humoral immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Methods Chemiluminescent immunoassay (CLIA) was used to detect the neutralizing antibody (Nabs) and IgG. Results Nabs peaked on days 57–96 after symptom onset and remained detected on days 97–132. The Nabs in the 32 patients who were dynamically monitored showed four changing patterns. The titers of Nabs and IgG were correlated, and three modes of relationship were found between them. Conclusions Nabs showed a regular change in the course of coronavirus disease 2019 (COVID-19). The detection of Nabs is very important for monitoring the course of COVID-19 and predicting the strength of antibody protection.

Integrated gate commutated thyristors (IGCTs) are critical components in high-voltage, high-current, and high-power conversion systems, particularly in offshore wind energy systems. However, the working environment of offshore wind energy conversion systems is extremely harsh. In this article, we propose an active damage control approach aiming at enhancing the reliability of the conversion system. By employing electro-thermal modeling for the equipment of the offshore wind energy conversion system, the junction temperature and fatigue damage of IGCT are simulated during the operation process. Using the improved model predictive current control (MPCC) method, active damage control effectively regulates the switching frequency of IGCT. IGCTs are symmetrically distributed on each leg of the converter, so the lifespan of the two IGCTs on each leg is also considered to be similar. This method balances the life of the IGCTs on the three legs of the converter and optimizes their utilization to the maximum extent. These measures effectively enhance the reliability of the conversion system and lower the operation and maintenance cost of high-power IGCT converters. The effectiveness of the proposed method is validated by co-simulation results by ANSYS and MATLAB/Simulink.

ObjectiveTo investigate the early effect of high tibial osteotomy (HTO) compared with combined arthroscopic surgery.MethodsA retrospective study was conducted on patients who underwent HTO at The First Affiliated Hospital of Shandong First Medical University from January 2018 to January 2022. 138 patients (163 knees) with knee osteoarthritis (KOA) treated with HTO were selected. The medial proximal tibial angle (MPTA), joint line convergence angle (JLCA), femoral tibial angle (FTA), hip-knee-ankle (HKA) angle, weight-bearing line (WBL) ratio of the knee joint, opening gap, opening angle, American Knee Society score (KSS), US Hospital for Special Surgery (HSS) score, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score were measured to determine the different effects between HTO and HTO combined with arthroscopic by logistic regression analysis.ResultsPatients with HTO combined with arthroscopic surgery have improved functional scores as well as imaging perspectives compared to preoperative. By multivariate logistic analysis, it was concluded that arthroscopic surgery and gender are influential factors in the outcome of HTO surgery. The postoperative KSS score was 2.702 times more likely to be classified as excellent in the HTO combined with arthroscopy group than in the HTO group [Exp (β) = 2.702, 95% CI (1.049–6.961), P = 0.039]; the postoperative KSS score was 0.349 times more likely to be classified as excellent in women than in men [Exp (β) = 0.349, 95% CI (0.138–0.883), P = 0.026].ConclusionBetter results with HTO combined with arthroscopic surgery. HTO combined with arthroscopy is a better choice in the surgical treatment of KOA.

The antisense RNA molecule is a unique DNA transcript consisting of 19–23 nucleotides, characterized by its complementary nature to mRNA. These antisense RNAs play a crucial role in regulating gene expression at various stages, including replication, transcription, and translation. Additionally, artificial antisense RNAs have demonstrated their ability to effectively modulate gene expression in host cells. Consequently, there has been a substantial increase in research dedicated to investigating the roles of antisense RNAs. These molecules have been found to be influential in various cellular processes, such as X-chromosome inactivation and imprinted silencing in healthy cells. However, it is important to recognize that in cancer cells; aberrantly expressed antisense RNAs can trigger the epigenetic silencing of tumor suppressor genes. Moreover, the presence of deletion-induced aberrant antisense RNAs can lead to the development of diseases through epigenetic silencing. One area of drug development worth mentioning is antisense oligonucleotides (ASOs), and a prime example of an oncogenic trans-acting long noncoding RNA (lncRNA) is HOTAIR (HOX transcript antisense RNA). NATs (noncoding antisense transcripts) are dysregulated in many cancers, and researchers are just beginning to unravel their roles as crucial regulators of cancer’s hallmarks, as well as their potential for cancer therapy. In this review, we summarize the emerging roles and mechanisms of antisense RNA and explore their application in cancer therapy.

Abstract Background This study was conducted to investigate the therapeutic potential of the skin-derived precursor Schwann cells for the treatment of erectile dysfunction in a rat model of bilateral cavernous nerve injury. Results The skin-derived precursor Schwann cells-treatment significantly restored erectile functions, accelerated the recovery of endothelial and smooth muscle tissues in the penis, and promoted nerve repair. The expression of p-Smad2/3 decreased after the treatment, which indicated significantly reduced fibrosis in the corpus cavernosum. Conclusions Implantation of skin-derived precursor Schwann cells is an effective therapeutic strategy for treating erectile dysfunction induced by bilateral cavernous nerve injury.

The performance of predictive current control (PCC) of induction motor (IM) drives is sensitive to the accuracy of the rotor flux angle estimation. In addition, predictive torque control (PTC), prioritizes control objectives by weighting factor in the cost function. It is tedious work to find a suitable weighting factor. In order to overcome these issues, a predictive power control (PPC) of IM drives is proposed in this paper. It directly controls the instantaneous output power of IM and does not require weighting factor and rotor flux angle estimation. This is achieved by the use of instantaneous power theory. The decoupling control of torque and rotor flux can be realized by controlling the output active and reactive power. The proposed method is easier to implement than PCC and PTC. To improve output efficiency, an output efficiency optimization strategy is proposed based on PPC. This is realized by adding the weighted output efficiency term into the cost function directly. Moreover, in order to get a better steady-state performance, an optimization strategy is proposed according to extend the output voltage vectors. Finally, the experimental and real-time hardware-in-the-loop (HiL) results validate that the proposed strategy is easier to implement and could optimize the output efficiency of the motor.

The research and promotion of electric drive systems for new energy transportation equipment is an important link in the realization of low-carbon transportation. Model predictive control is an effective new control strategy for electrical drive systems. Taking the three phase induction motor drive system as the research object, three kinds of model predictive torque control methods are reviewed and analyzed in depth, and a theoretical proof of Pareto optimality of MPC methods without weighting factors is established. Predictive torque control is a classical model predictive control method for induction motor drives. When using it, a trial-and-error method is usually used to set appropriate weighting factors for different control objectives, which strongly depends on the designer’s experience. By changing the structure of the cost function, the sequential model predictive control eliminates the weighting factors and improves the control effect of the stator current. The even-handed model predictive control utilizes the interaction error and considers all the control objectives at the same time, so that the optimization order of the control objectives changes with the working conditions, which further improves the control performance. Through theoretical analysis and experimental test, this paper illustrates the performance differences between traditional predictive torque control, sequential model predictive control and even-handed model predictive control.

Silage is the most important component of a ruminant diet and has important production and health significance in ruminant production. The aim of the research was to investigate how the mixed silage of Chinese cabbage waste and rice straw (mixed silage) impacts the fecal microorganisms and metabolites in Hu sheep using Illumina sequencing and metabolomic analysis. A total of 16 Hu sheep (8 rams and 8 ewes) weighing about 39 kg and 5.5 months old were used as experimental sheep and divided into two groups (4 rams and 4 ewes, n = 8) using the principle of randomized trials: the control group with peanut sprouts, corn husks, and sorghum husks as roughage and the silage group with the mixed silage as roughage. There were no significant differences in the average daily gain (ADG), dry matter intake (DMI), or feed conversion rate (FCR) between the control group and the mixed silage groups (p > 0.05). Microbiome results showed that 15 microorganisms such as Ruminococcaceae UCG 010, Breznakia, Erysipelothrix, Desulfovibrio, Succiniclasticum, and Shuttleworthia were significantly different between the two groups. In addition, metabolomics showed that the mixed silage modulated the concentrations and metabolic pathways of metabolites in the manure. Significantly different metabolites were mainly enriched in amino acid anabolism (“glycine, serine, and threonine metabolism”, “valine, leucine, and isoleucine biosynthesis”, “arginine biosynthesis”, etc.), nucleic acid metabolism (pyrimidine metabolism). In conclusion, the addition of mixed silage to the diet of Hu sheep can alter the structure of the hindgut microflora and regulate the metabolism of amino acids and nucleotides, which affects health performance.

Most commercially available soy sauce is fermented by high-salt liquid-state (HS) fermentation, which has an excessive salt content and a long fermentation period. In this study, a new salt-reduced fermentation (SR) soy sauce technology involving multiple strains of bacteria was developed to reduce consumers’ salt intake. The SR soy sauce was found to have an amino acid nitrogen content of 8.40 g/L and over 80 kinds of flavor substances, which were significantly higher than those of low-salt solid-state fermented soy sauce and approximately equal to HS soy sauce. Compared with HS soy sauce, the salt content of the SR soy sauce was reduced by 59.2%, achieving the salt reduction goal. The proportion of umami amino acids in SR soy sauce reached 32.0% of the total level, enhancing SR soy sauce’s quality. Hence, the new fermentation process can decrease salt content and shorten fermentation time.

Improper disposal of vegetable waste can cause serious environmental pollution, but because they contain huge water content and organic matter, they are not suitable for disposal by methods such as incineration and landfill. However, vegetable waste contains a large amount of nutrients and have some complementary effects with rice straw in terms of physical structure, nutrients, and moisture. In this experiment, the plant feed (corn husk, peanut shells and sorghum shells) was used as the control group (CON group), and the mixed silage of Chinese cabbage waste and rice straw (mixed silage) was used as the experiment group (TRE group), and its safety performance was evaluated by testing its toxin content, pesticide residues, vitamin contents and feeding experiment of Hu sheep. In the animal experiment, 16 healthy Hu sheep (5.5 months, 39.11 ± 4.16 kg) were randomly divided into two groups of 8 each. The results of the safety performance evaluation showed that the content of mycotoxins, heavy metals, and nitrites as well as pesticide residues in the crude feeds of both groups were within the range of Chinese feed hygiene standards. In addition, the levels of deoxynivalenol (DON) and aflatoxin (AFT) in the CON group were lower, while the content of ochratoxin (OTA) and zearalenone were higher than those in the TRE group (p < 0.05). The levels of plumbum(Pb), chromium (Cr), cadmium (Cd), and nitrite in the CON group were lower than the mixed silage, while the levels of As were higher than the mixed silage (p < 0.05). It is worth noticing that the content of vitamin B2 (VB2) and vitamin C (VC) in the TRE group was higher than the CON group (p < 0.05). The results of the feeding experiment showed that the mixed silage did not affect the growth performance, nutrient digestibility, organ index, and intestinal index of Hu sheep (p > 0.05). In addition, the mixed silage reduced the weight of omasum, the proportion of omasum to live weight before slaughter, the amount of compound stomach, and the proportion of compound stomach to live weight before slaughter, which were higher than those in the TRE group (p < 0.05). The thickness of the basal layer of the rumen abdominal sac, the red blood cell count, the content of IL-10, and TNF-α in the blood, and TNF-α content in the rumen of the Hu sheep in the TRE group were higher than the CON group (p < 0.05). In conclusion, the feed safety index content of the mixed silage did not exceed the Chinese feed hygiene and safety standards and did not cause adverse effects on the growth performance of the Hu sheep, and it improved the immune performance of the body and digestive tract of the sheep to a certain extent and promoted the healthy development of the sheep.

Manipulating dietary nutrients, especially protein fractions, holds significance in enhancing the antioxidant capacity and immunity function of ruminants. This study investigated the impact of dietary adjustments in soluble protein (SP) levels, in conjunction with a reduction in crude protein (CP) content, on the antioxidant capacity, inflammatory response, carcass characteristics, and meat quality of sheep. This study had four dietary treatments, including a control diet (CON) adhering to NRC standards with a CP content of 16.7% on a dry matter basis and three diets with an approximately 10% reduction in CP content compared to CON with SP levels (% of CP) of 21.2 (SPA), 25.9 (SPB) and 29.4% (SPC), respectively. Thirty-two healthy male Hu sheep, with an initial live weight of 40.37 ± 1.18 kg and age of 6 months, were randomly divided into four groups to receive these respective diets. Our data revealed no significant differences in slaughter performance among treatments (p > 0.05), although low-protein treatments decreased the stomachus compositus index (p < 0.05). Compared with CON, as SP was adjusted to 21.2%, total antioxidant capacity (T-AOC) and catalase (CAT) concentrations were decreased in the serum (p < 0.05), glutathione peroxidase (GSH-Px) content was decreased in jejunum and ileum (p < 0.05), superoxide dismutase (SOD) concentration was reduced in the duodenum (p < 0.05), and malondialdehyde (MDA) content was increased in spleen and ileum (p < 0.05). On the other hand, pro-inflammatory cytokine (IL-1β, IL-6 and IL-8) contents were upregulated in the serum (p < 0.05), while immunoglobulin (IgA and IgM) contents were reduced in the duodenum (p < 0.05) with SP adjustments. Additionally, the SPB and SPC diets reduced the content of saturated fatty acids and increased the content of polyunsaturated fatty acids compared with CON (p < 0.05), along with retention in the tenderness and water-holding capacity of the longissimus lumborum muscle. In summary, reducing CP by 10% with an SP proportion of ~25–30% improved meat quality without compromising antioxidant capacity and immunity function, while lower SP levels had adverse effects.

Résumé Contexte La dysfonction érectile (DE) survient souvent en raison d’une lésion du nerf caverneux après une chirurgie colorectale. Les thérapies cellulaires ont un grand potentiel dans le traitement de la DE liée aux lésions du nerf caverneux; cependant, ces thérapies doivent être optimisées. Dans cette étude, nous avons exploré les effets thérapeutiques des cellules souches adipeuses (ADSC) allogéniques préconditionnées par lipopolysaccharides (L-ADSC) sur la dysfonction érectile induite par lésion du nerf caverneux chez le rat. Résultats Les résultats de l’étude in vitro ont révélé que les lipopolysaccharides à faible dose pourraient augmenter la viabilité des cellules souches adipeuses, inhiber l’activation de la caspase 3 induite par le peroxyde d’hydrogène, et favoriser la migration cellulaire. Comparé au surnageant des cellules souches adipeuses, le surnageant des cellules souches préconditionnées (L-ADSC) pourrait mieux réduire la fibrose, dans les cellules musculaires lisses du corps caverneux, induite par la transformation du facteur de croissance-protéine bêta 1. Dans l’étude in vivo, par comparaison au traitement par ADSC, la thérapie par L-ADSC indiquait une meilleure amélioration de la fonction érectile en augmentant le contenu musculaire lisse et en soulageant la fibrose pénienne chez le rat 2 semaines après lésion du nerf caverneux. Le résultat pourrait être lié à l’augmentation de la teneur en facteur de croissance hépatocytaire dans le corps caverneux, et de la protéine de base de la myéline dans le ganglion pelvien majeur. Conclusions Le traitement par cellules souches adipeuses (ADSC) allogéniques préconditionnées par lipopolysaccharides (L-ADSC) pourrait être une approche prometteuse pour restaurer la fonction érectile après lésion du nerf caverneux.

ObjectiveTo investigate the influencing factors of functional recovery after high tibial osteotomy (HTO).MethodsA retrospective research was carried on 98 patients who underwent HTO between January 2018 and December 2020. In each case, the medial proximal tibial angle (MPTA), joint line convergence angle (JLCA), femoral tibial angle (FTA), hip-knee-ankle (HKA), weight bearing line (WBL) ratio of the knee joint, opening gap, opening angle, American knee society knee score (KSS), US Hospital for Special Surgery (HSS) score, Lysholm score, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were measured to determine postoperative function and influential factors of pain through logistic regression analysis.ResultsThe follow-up time was between 18 and 42 months after operation with an average of 27.66 ± 12.9 per month. Overall functional scores were significantly improved. The influencing factors that may affect the postoperative effect of HTO include age and preoperative WBL ratio of the knee joint (WBL%). After incorporating these two factors into the multivariate logistic regression analysis, for every 1 unit increase in the preoperative WBL%, the probability of postoperative HSS being superior is 1.06 times higher than before [Exp(β): 1.062, 95% CI: 1.01–1.1, p = 0.018]. For every year increase in age, the probability of an excellent HSS score after surgery was 0.84 times higher than that before surgery [Exp(β): 0.843, 95% CI: 0.718–0.989, p = 0.036]. Preoperative WBL% ≥ 14.37 was 17.4 times more likely to be rated as excellent postoperative HSS than that

Model predictive control (MPC) is an efficient and multi-functional control scheme for synchronous permanent magnet generators (PMSGs). However, the effective management of traditional MPC depends on precise system models. Multiple uncertainties of permanent magnet flux, motor inductance, filter inductance and parameter measurement noise will limit MPC’s performance. The conventional linear extended state observer (ESO) can perform robust predictive control of the ultralocal model of the PMSG system to cope with parameter mismatches. However, the ESO is limited in balancing disturbance rejection with measurement noise attenuation. Since the amplification of high-frequency noise pollution can lead to both poor control performance and system instability, this challenge is of significant importance. To solve the problem, a new hybrid parallel cascaded ESO (PCESO) model-free predictive control framework is proposed using the three-level neutral-point-clamped (NPC) power electronic converter, on both the machine side and grid side. Analytical discussions of the time and frequency domain characteristics of the PCESO demonstrate its superior characteristics over the ESO. The proposed method can effectively balance parameter mismatch, disturbance rejection and high-frequency noise suppression. Finally, the effectiveness of the proposed method, under uncertainties of parameter mismatches, measurement noise and permanent magnet flux, is verified through real-time hardware-in-the-loop tests on a back-to-back grid-tied PMSG interfaced with an NPC power converter.

Modular multilevel converters (MMCs) are widely used in voltage-sourced, converter-based high-voltage DC systems due to their modular design, scalability, and fault tolerance capabilities. In MMCs, multi-variable control objectives can be employed by using model predictive control (MPC) due to its fast dynamic response and ease of implementation. Nonetheless, conventional MPC techniques for MMCs have shortcomings, including high computational requirements, poor circulating current, and capacitor voltage fluctuation suppression. First, this study proposes an adaptive MPC technique that adapts the number of candidate combinations to the steady and transient states, significantly reducing the computational burden. Second, an improved hybrid combination of an MPC with a proportional-resonance (PR) controller enhances the circulating current and capacitor voltage fluctuation suppression performance. According to the phase difference between the circulating current and the capacitor voltage, the circulating current and capacitor voltage can be suppressed at different times by changing the circulating current reference of the PR controller. The switching frequency can be reduced by using the PR controller’s output to adjust the input submodule number instead of changing the duty cycle. The proposed techniques were validated by simulations and experimental case studies with a three-phase grid-connected MMC.

Silage is rich in nutrients, which can make up for the lack of seasonal roughage, and has a certain promotion effect on the intensive feeding of ruminants. In addition, silage can maintain the rumen function of ruminants to a certain extent and reduce the risk of rumen acidosis and abomasum translocation. The purpose of this study was to investigate the effects of the mixed silage of Chinese cabbage waste and rice straw (mixed silage) on antioxidant performance, rumen microbial population, and fermentation metabolism of Hu sheep. The 16 healthy Hu sheep (eight rams and eight ewes, 39.11 ± 1.16 kg, 5.5 months) were randomly divided into two groups (the control group and the mixed silage group) with eight animals (four rams and four ewes) in each group. The control group was fed with farm roughage (peanut seedlings, corn husk, and high grain shell) as forage, and the mixed silage group was fed with the mixed silage as forage. The results showed that the mixed silage had no effect on the growth performance of Hu sheep (p > 0.05). Ruminal butyric acid, total volatile fatty acids (TVFA), and ammonia nitrogen (NH3-N) concentration in the mixed silage group were increased, whereas the pH was decreased (p

The rapid growth of energy demand requires progressive energy generation. This, together with the demand for higher efficiency and flexibility, has promoted the application of power electronics in energy systems. During the past decade, model predictive control (MPC) of power electronics has witnessed significant advancements in both dynamic performance and optimal control of the multi-objective terms. Several of these terms can have equal control priorities, resulting in a symmetrical cost function; however, most objectives have different priorities and require weighting factors to resolve the asymmetry in the cost function. Currently, researchers continue to encounter challenges in the optimal design of weighting factors. Moreover, the relative performance of different techniques that either utilize or avoid the weighting factor are uncertain. Therefore, this study focuses on weighting factor design techniques in the literature as applied to wind/solar energy conversion, microgrids, grid-connected converters, and other high-performance converter-based systems. These are grouped under the heuristic, offline tuning, sequential, and online optimization methods. This study demonstrates that optimal online tuning of weighting factors and sequential MPC methods can both offer improved robustness against parameter uncertainties. In addition, the advantages and limitations of different techniques are highlighted.

Permanent magnet synchronous generator (PMSG) wind power system with full power rating converter configuration is especially suitable for wind energy applications. Direct model predictive control (DMPC) has led to more possibilities in terms of choice because of its straightforward concept for PMSG wind turbine systems in high-power off-shore wind farms. However, due to complete dependence on the model knowledge, parameter mismatches will seriously deteriorate the system control performances. This work presents a model/parameter-independent predictive control method with a novel mechanism to update current/power variations online. The proposed method makes use of only two measurements from the former intervals and the selected control vectors to estimate all variations of the candidate vectors in the present interval. Benefiting from this updating mechanism, the proposed method is completely independent of the model parameters in the state prediction. However, it still has a very low calculating requirement and smooth current/power variation waveforms. The proposed method is compared with classical DMPC. The results validate that the proposed solution outperforms the classical DMPC with model deviations, with considerably improved robustness.

Finite Control Set Model Predictive Control (FCS-MPC), thanks to its simple and powerful concept, has been applied widely to control the multilevel converters. FCS-MPC allows the control of several objectives and can incorporate restrictions, even nonlinear, into the mathematical model of the system under consideration. However, FCS-MPC needs to evaluate all the switching states of the multilevel converter to find the best switching state to be applied in the next sampling time. For higher-level multilevel converters, this iterative action requires computational capacity that is far beyond the digital controller’s capacity in the current market. This paper proposes a new predictive geometric pre-filtering strategy to reduce the iterations and computational burden without affecting the dynamic performance of FCS-MPC. This method consists of a novel pre-filtering stage that uses the predictive model of the system and geometrical properties to find the sector where the reference vector is located and evaluates few vectors that constitute the optimal sector. The proposed method is experimentally validated using a four-level three-cell flying capacitor converter with 512 voltage vectors, obtaining a 64% reduction in the computational burden, while achieving excellent electrical performance indices and maintains the high dynamic performance of the standard FCS-MPC.

Summary: The priority of developing countries in the clean energy transition is to attain industrialization primarily with low-carbon energy sources; this presents challenges that industrialized nations did not experience. Developing economies need to grapple with the question: “Should sustainable human development be achieved at the price of economic growth?” Therefore, this article brings perspective to the theme of clean energy transition for development. We highlight three peculiarities of developing economies which will strongly influence their approach to the clean transition: low grid capacity and inefficiency, lower rates of urbanization, and youth demographics. Owing to these, effective low-cost technologies and novel pathways that can facilitate clean transition in a sustainable socio-economic framework are needed. In particular, we propose that mature dispatchable low-carbon energy sources should be prioritized as a strategy to harness local natural resources, and maximize existing indigenous skilled labor. The perspective also highlights several recommendations to help researchers and policy makers look more critically into possible solutions for the Global South’s timely participation in the clean energy transition without sacrificing economic growth potentials.

This paper proposes a new concept of synthesized voltage vector to address dead-time effect issue for Finite Control Set Model Predictive Control (FCS-MPC) technique. For a voltage source inverter (VSI), dead-time is inevitably inserted between the turn off and turn on instants of power devices to avoid short circuit phenomenon. The influence of dead-time leads to output voltage vector error of three-phase inverters. Furthermore, it will result in computing deviation in cost function, and will deteriorate the performance of the system if not properly dealt with. In this paper, the problem is clearly analyzed, and the solution to this issue is proposed by introducing a synthesized voltage vector. The proposed solution is verified by Hardware-in-the-loop (HiL) test in real time, and results validate the effectiveness of the proposed solution.

Abstract The plasmon-induced transparency (PIT), which is destructive interference between the superradiation mode and the subradiation mode, is studied in patterned graphene-based terahertz metasurface composed of graphene ribbons and graphene strips. As the results of finite-difference time-domain (FDTD) simulation and coupled-mode theory (CMT) fitting, the PIT can be dynamically modulated by the dual-mode. The left (right) transmission dip is mainly tailored by the gate voltage applied to graphene ribbons (stripes), respectively, meaning a dual-mode on-to-off modulator is realized. Surprisingly, an absorbance of 50% and slow-light property of 0.7 ps are also achieved, demonstrating the proposed PIT metasurface has important applications in absorption and slow-light. In addition, coupling effects between the graphene ribbons and the graphene strips in PIT metasurface with different structural parameters also are studied in detail. Thus, the proposed structure provides a new basis for the dual-mode on-to-off multi-function modulators.

In the medium-voltage AC/DC distribution networks with distributed renewable sources on islands, a multi-port receiver is the key factor for hybrid power conversion. However, the most used modular multilevel converter (MMC)-based multi-port converters (MCs) face the coordination and complexity challenges due to their double-stage control system and voltage-balancing control of capacitors. In particular, the control system is more unstable and complicated when the control of circulating currents is considered. In this paper, an isolated modular multilevel converter (I-MMC) is used as a receiver, and a unified coordinated control scheme based on the multiple modulation freedoms is proposed. Due to the voltage clamping of high-frequency transformers, there is no concern of the capacitors' voltage-balancing control. Based on the proposed single-stage control system, the unified coordinated control scheme solves the coordination problem of the MMC-based MCs. The multiple modulation freedoms corresponding to an AC port, two DC ports, and three-phase circulating currents can independently control respective targets. The control structure is simplified, while the control freedoms are ensured. Experimental results confirming the performance of the designed control system is shown.

Ruminants account for a relatively large share of global nitrogen (N) emissions. It has been reported that nutrition control and precise feeding can improve the N efficiency of ruminants. The objective of the study was to determine the effects of soluble protein (SP) levels in low-protein diets on growth performance, nutrient digestibility, rumen microbiota, and metabolites, as well as their associations of N metabolism in fattening Hu sheep. Approximately 6-month-old, 32 healthy fattening male Hu sheep with similar genetic merit and an initial body weight of 40.37 ± 1.18 kg were selected, and divided into four groups (n = 8) using the following completely randomized design: the control diet (CON) with a 16.7% crude protein (CP) content was prepared to meet the nutritional requirements of fattening sheep [body weight (BW): 40 kg, average daily gain (ADG): 200–250 g/d] according to the NRC recommendations; other three include low protein diets (LPA, LPB, and LPC) of CP decreased by ~10%, with SP proportion (%CP) of 21.2, 25.9, and 29.4 respectively. The feeding trial lasted for 5 weeks including the first week of adaptation. The results showed no difference in the growth performance (P > 0.05); DM and CP digestibility were higher in LPB and LPC, with maximum organic matter digestibility in LPB (P < 0.05). Low-protein diets decreased serum urea-N whereas urinary urea-N was lower in LPB and LPC (P < 0.05), while N retention and the biological value of N were higher in LPB and LPC (P < 0.05). Ruminal NH3-N concentration in LPA and LPB was low than CON (P < 0.05), while total volatile fatty acid (TVFA), acetate, propionate, and butanoate were all lowest in LPA (P < 0.05). In the rumen microbiome, LPB increased the community richness in Prevotellaceae and Prevotella_1 (P < 0.05); Metabolomics analysis revealed low-protein diets downregulated the amino acid metabolism pathways, while the biosynthesis of unsaturated fatty acids along with vitamin B6 metabolism were upregulated with increased SP. These findings could help us understand the role of different SP levels in the regulation of rumen microbial metabolism and N efficiency. Overall, low-protein diets (CP decreased by ~10%) can reduce serum urea-N and ruminal NH3-N without affecting the growth performance of fattening Hu sheep. Additionally higher N efficiency was obtained with an SP proportion of ~25–30%.

Studies have shown that exogenous thiamine (THI) supplementation can alleviate inflammation and promote rumen epithelial development in goats and cows. This research aimed to evaluate the effect of THI supplementation on LPS-induced inflammation and energy metabolic dysregulation in RECs of goats. Cells were stimulated with either 5 μg/mL THI for 18 h (THI group) or with 5 μg/mL LPS for 6 h (LPS group). The CON group was stimulated with DMEM/F-12 medium without THI for 18 h. The LPTH group was pretreated with THI for 18 h, followed by LPS stimulation for 6 h. THI supplementation decreased the ROS content (p < 0.05), as well as the ratios of phosphorylated (p)-p65 to p65 (p < 0.05) and p-AMPKα to AMPKα (p < 0.05). Interestingly, when the p38 gene was overexpressed in the LPTH group, the ratio of p-p65 to p65 and p-AMPKα to AMPKα proteins significantly increased, and ATP content decreased (p < 0.05). Our results suggest that THI possesses anti-inflammatory and metabolic-modulatory effects in RECs. The mechanism is largely related to the suppression of the NF-κB/p38 MAPK/AMPK signaling pathway. Additionally, we also revealed that THI supplementation can inhibit LPS-induced oxidative damage and apoptosis to protect mitochondrial function in RECs.

The modular multilevel converter (MMC) has become a promising topology for widespread power converter applications. However, an evident circulating current flowing between the phases will increase system losses and complicate the heatsink design. This paper proposes a novel hybrid model predictive control method for MMCs. This method utilizes an indirect structure MPC and a sorting algorithm to implement current tracking and capacitor voltages balancing, considerably resulting in reduced calculation burden. In addition, different from the conventional MPC solutions, we add a simple proportional-integral (PI) controller to suppress circulating current through modifying the submodule (SM) inserted number, which is parallel to the MPC loop. This hybrid control solution combines both advantages of MPC and linear control, evidently resulting in improved performance of circulating current. Finally, the MATLAB/Simulink results of an 11-level MMC system verify the effectiveness of the proposed solution.

A large number of joint friction pairs work during the work of scroll compressors, resulting in high energy consumption and short service life of scroll compressors. To improve the tribological performance of friction pairs of the scroll compressors, the C-MoS2-PTFE (Polytetrafluoroethylene) lubrication coating is prepared through spraying technology on the surface of 4032 aluminum alloy, a common material for scroll compressors. The microstructure of the C-MoS2-PTFE coating was analyzed by X-ray diffractometer (XRD) and scanning electron microscope (SEM), and the wear behavior of the coating under different loads was studied by reciprocating friction and wear testing machine and three-dimensional profiler. The surface of the grinding marks was analyzed by SEM and energy density spectrum (EDS). The performance was compared with the anodized film of 4032 aluminum alloy and the Ni-coated coating of 4032 aluminum alloy. The experimental results show that the C-MoS2-PTFE coating has a dense structure, and the hardness is 35 HV0.1. Under dry friction conditions, the C-MoS2-PTFE coating has excellent wear reduction and wear resistance, and the coefficient of friction and wears rate under different loads are less than those of the anodized film of 4032 aluminum alloy and the Ni-plated coating. The wear mechanisms of C-MoS2-PTFE coating are fatigue wear, adhesive wear, abrasive wear, and oxidation wear under different loads.

In recent years, in response to increasing environmental concerns, advances in renewable energy technology and reduced costs have caused a significant increase in the penetration of distributed generation resources in distribution networks. Nonetheless, the connection of distributed generation resources to distribution networks has created new challenges in the control, operation, and management of network reliability. This article is a review on the model predictive control (MPC) for distributed energy resources (DER) in microgrids. The solutions of MPC for energy conversion of solar photovoltaic, wind, and energy storage systems are covered in detail. MPC’s applications for increasing reliability of grid-connected converters under (a)symmetrical grid faults are also discussed. The promising potentials of the applications of MPC to the stable multi-variable control performance of DERs are highlighted. This work reflects strong symmetry on MPC control strategies and provides guidance map for readers to facilitate future research works in these exciting fields.

The energy harvested by an ocean wave energy converter (WEC) can be enhanced by a well-designed wave-by-wave control strategy. One of such superior control methods is model predictive control (MPC), which is a nonlinear constrained optimization control strategy. A limitation of the classical MPC algorithm is its requirement of an accurate WEC dynamic model for real-time implementation. This article overcomes this challenge by proposing a data-driven MPC scheme for wave energy converters. The data-based WEC model is developed by a Gaussian process (encompassing mean predictions and symmetric uncertainties) for a more accurate description of nonlinear and unmodeled system dynamics. A cross-entropy solver for data-driven MPC is employed for rapid, high-performance results, which samples trajectories from Gaussian distributions based on the concept of the symmetry principle. The proposed strategy is verified numerically by simulations which demonstrate its superior performance over a classical complex-conjugate controller.

A cascaded deadbeat predictive control strategy with online disturbance compensation is proposed for a three-phase interleaved boost converter in this paper. The topology of the three-phase interleaved converter is symmetric, so the inner loop controller is also designed symmetrically. For the purpose of realizing the error-free tracking of reference value, the deadbeat predictive control method is adopted for inner and outer loops with Luenberger observers, which are designed to estimate and compensate the disturbances of load variation in the power model as well as the unknown resistor of inductance in the current model. To eliminate the influence of a time delay, a two-step predictive control method is adopted in the predictive model. In the aspect of parameter design, the pole placement method is adopted to determine the gain of the observer. A series of simulations and experiments are carried out to test the proposed strategy under steady and dynamic conditions. It is shown that the proposed control strategy has faster dynamic response and stronger robustness against disturbance than the conventional model predictive control.

A hybrid energy-storage system (HESS), which fully utilizes the durability of energy-oriented storage devices and the rapidity of power-oriented storage devices, is an efficient solution to managing energy and power legitimately and symmetrically. Hence, research into these systems is drawing more attention with substantial findings. A battery–supercapacitor hybrid energy-storage system (BS-HESS) is widely adopted in the fields of renewable energy integration, smart- and micro-grids, energy integration systems, etc. Focusing on the BS-HESS, in this work we present a comprehensive survey including technologies of the battery management system (BMS), power conversion system (PCS), energy management system (EMS), predictive control techniques of the underlying system, application and cost-effective feasibility aspects, etc. This work reflects strong symmetry on different aspects of designing an HESS, and provides guidelines and design references for the research and application of an HESS.

Sclerosing encapsulating peritonitis (SEP) is a disease that is rarely encountered clinically. Preoperative diagnosis of SEP can be difficult. However, with imaging technology, such as computed tomography (CT), this condition can be diagnosed without surgery and pathological analysis. SEP is characterized by small intestine being partially or completely encased by a layer of a thick grayish-white fibrocollagenous membrane similar to a cocoon. The most common symptoms of SEP are abdominal pain, nausea, and vomiting. SEP often leads to intestinal obstruction. Our hospital treated three emergency patients who complained of acute or chronic abdominal pain. CT showed “cauliflower sign” in two cases. The three patients were diagnosed with SEP intraoperatively. In a female patient with ascites, the situation was extremely serious, and this condition had not been reported in detail previously. Fortunately, all patients were discharged without complications. We should pay special attention to patients with SEP who have ascites, which indicates a serious situation.

Since image background is normally composed of congenial regions, it can be represented by a feature dictionary via sparse representation. Based on this theory, the authors propose a novel bottom‐up saliency detection method that unites the syncretic merits of sparse representation and multi‐hierarchical layers. In contrast to most pre‐existing sparse‐based approaches that only highlight the boundaries of a target, the proposed method highlights the entire object even if it is large. Given a source image, a multi‐scale background dictionary is structured with the features form different layers. Each region of the image is then reconstructed by the dictionary to compute its reconstruction error as a saliency score. Although a reconstruction map can be generated by the saliency scores, it is not good enough to be the final result because of low resolution and high error detection rates. Therefore, in middle cue, they propose a multi‐scale contour zooming approach to address the error detection across the hierarchical layers. To improve the resolution of the final detection, a pixel‐level rectification based on the Bayesian observation likelihood is calculated as the bottom cue. Combining sparse representation and multi‐scale correction, the precision of the final saliency map is significantly improved for the detection results.

The study was conducted in vitro to investigate the effects of different ratios of Urtica cannabina and Leymus chinensis on fiber microstructure and digestibility in ruminal fluid. The experiment was divided into five groups based on the U. cannabina/L. chinensis ratios: A (0:100), B (30:70), C (50:50), D (70:30), and E (100:0). The culture medium was collected at 0, 1, 3, 6, 12, and 24 h. The results showed that: (1) in vitro crude protein degradability (IVCPD) was higher in group A, whereas in vitro neutral detergent fiber degradability (IVNDFD) was higher in group C (p < 0.05); (2) protozoa count was increased from 1 h to 3 h and decreased afterwards, with significant differences observed in several genera (p < 0.05); (3) microbial crude protein (MCP) contents at 1, 3, 6, and 24 h were higher in groups A and C (p < 0.05); (4) the basic tissue of U. cannabina was gradually degraded. At 24h, the secondary xylem vessel structure was observed in groups B and C, but not in groups D and E. In summary, there was higher neutral detergent fiber (NDF) digestibility, higher rumen MCP contents, and lower protozoa count, showing the significance of the 50:50 ratio for microbial growth and fiber digestibility.

A terahertz multifunction modulator composed of upper-layer double graphene ribbons and lower-layer a graphene strip, which can generate a Fano resonance produced by hybrid between a broad mode and a narrow mode, is proposed to realize electro-optical switch and filtering function. The electric field distribution, hybrid theory, and quantum level theory are all employed to explain the Fano resonance, whose transmission spectra are fitted by coupled mode theory. In comparison to other graphene-based terahertz modulators, the amplitude modulation degree can reach 99.57%, meaning an excellent electro-optical switch can be realized. Moreover, the extinction ratio of Fano resonance can reach 99.70%, demonstrating an unparalleled electro-optical filter is implemented. Finally, variations in the lateral and longitudinal lengths of the lower-layer a graphene strip enable excellent dual-band, triple-band filters. Thus, this work provides a new way to implement terahertz multi-function modulators.

A novel multilayer terahertz metamaterial composed of double rectangle, vertical single rectangle, vertical double rectangle and single rectangle graphene layer is proposed. The dynamic adjustable triple plasmon induced transparency (PIT) is realized by coupling two bright modes and two dark modes, which is an especial synergy effect between two single-PIT. Coupled mode theory contained four resonators is employed to explain the triple-PIT, and the theoretical results exhibit excellent consistency with finite-difference time-domain. Surprisingly, the triple-PIT can evolve into a dual-PIT or a single-PIT only by changing the Fermi level of graphene, and the amplitude modulation degrees at the four resonance frequencies of the triple-PIT are 74.7%, 87.8%, 76.5%, and 77.7%, respectively. In addition, a simultaneous switching at multiple frequencies is realized by adjusting different Fermi levels. Therefore, this study not only lays the foundation for explaining phenomenon of the triple-PIT but also puts forward new ideas for the design of optoelectronic device.

In this work, volatile organic compounds (VOCs) in the ambient air of a secondary fiber paper mill were analyzed. For the sake of studying pollution comprehensively, four sites in the paper mill were analyzed and active sampling methods were used. Desorption was carried out with two solvents, carbon disulfide and dichloromethane. The compositions of VOCs were determined by gas chromatography-mass spectrometry (GC-MS) method. The main identified substances in the four sites were as follows: (1) waste paper sorting room: alkanes, phenols, and esters; (2) papermaking workshop: benzene series, alkanes, ethers, and phenols; (3) vacuum pump outlet: benzene series and phenols; and (4) office area: benzene series and phenols. Two main toxic substances in VOCs, the benzene series and phenols, were detected in the ambient air of the paper mill. The benzene series existed in three places along the main process of the paper mill and even existed in the office area, which was far away from the production line. Additionally, phenols were detected in all sampling locations in the paper mill.

Field oriented control (FOC), direct torque control (DTC) and finite set model predictive control (FS-MPC) are different strategies for high performance electrical drive systems. FOC uses linear controllers and pulse width modulation (PWM) to control the fundamental components of the load voltages. On the other hand, DTC and FS-MPC are nonlinear strategies that generate directly the voltage vectors in the absence of a modulator. This paper presents all three methods starting from theoretic operating principles, control structures and implementation. Experimental assessment is performed to discuss their advantages and limitations in detail. As main conclusions of this work, it is affirmed that different strategies have their own merits and all meet the requirements of modern high performance drives.