Identification and characterization of an efficient acyl-CoA: diacylglycerol acyltransferase 1 (DGAT1) gene from the microalga Chlorella ellipsoidea

RT-PCR detection of DGAT1 genes in transgenic yeast (INVSc1). The yeast actin was used as an internal control. 1, The yeast transformed with pYES2.0; 2–5, the yeast expressing AtDGAT1, GmDGAT1, BnDGAT1 and CeDGAT1, respectively. (DOCX 55 kb

Identification and Characterization of an Efficient acyl-CoA:Diacylglycerol Acyltransferase 1 (\u3cem\u3eDGAT1\u3c/em\u3e) Gene from the Microalga \u3cem\u3eChlorella ellipsoidea\u3c/em\u3e

Background: Oil in the form of triacylglycerols (TAGs) is quantitatively the most important storage form of energy for eukaryotic cells. Diacylglycerol acyltransferase (DGAT) is considered the rate-limiting enzyme for TAG accumulation. Chlorella, a unicellular eukaryotic green alga, has attracted much attention as a potential feedstock for renewable energy production. However, the function of DGAT1 in Chlorella has not been reported. Results: A full-length cDNA encoding a putative diacylglycerol acyltransferase 1 (DGAT1, EC 2.3.1.20) was obtained from Chlorella ellipsoidea. The 2,142 bp open reading frame of this cDNA, designated CeDGAT1, encodes a protein of 713 amino acids showing no more than 40% identity with DGAT1s of higher plants. Transcript analysis showed that the expression level of CeDGAT1 markedly increased under nitrogen starvation, which led to significant triacylglycerol (TAG) accumulation. CeDGAT1 activity was confirmed in the yeast quadruple mutant strain H1246 by restoring its ability to produce TAG. Upon expression of CeDGAT1, the total fatty acid content in wild-type yeast (INVSc1) increased by 142%, significantly higher than that transformed with DGAT1s from higher plants, including even the oil crop soybean. The over-expression of CeDGAT1 under the NOS promoter in wild-type Arabidopsis thaliana and Brassica napus var. Westar significantly increased the oil content by 8–37% and 12–18% and the average 1,000-seed weight by 9–15% and 6–29%, respectively, but did not alter the fatty acid composition of the seed oil. The net increase in the 1,000-seed total lipid content was up to 25–50% in both transgenic Arabidopsis and B. napus. Conclusions: We identified a gene encoding DGAT1 in C. ellipsoidea and confirmed that it plays an important role in TAG accumulation. This is the first functional analysis of DGAT1 in Chlorella. This information is important for understanding lipid synthesis and accumulation in Chlorella and for genetic engineering to enhance oil production in microalgae and oil plants

Byzantine Robust Cooperative Multi-Agent Reinforcement Learning as a Bayesian Game

In this study, we explore the robustness of cooperative multi-agent reinforcement learning (c-MARL) against Byzantine failures, where any agent can enact arbitrary, worst-case actions due to malfunction or adversarial attack. To address the uncertainty that any agent can be adversarial, we propose a Bayesian Adversarial Robust Dec-POMDP (BARDec-POMDP) framework, which views Byzantine adversaries as nature-dictated types, represented by a separate transition. This allows agents to learn policies grounded on their posterior beliefs about the type of other agents, fostering collaboration with identified allies and minimizing vulnerability to adversarial manipulation. We define the optimal solution to the BARDec-POMDP as an ex post robust Bayesian Markov perfect equilibrium, which we proof to exist and weakly dominates the equilibrium of previous robust MARL approaches. To realize this equilibrium, we put forward a two-timescale actor-critic algorithm with almost sure convergence under specific conditions. Experimentation on matrix games, level-based foraging and StarCraft II indicate that, even under worst-case perturbations, our method successfully acquires intricate micromanagement skills and adaptively aligns with allies, demonstrating resilience against non-oblivious adversaries, random allies, observation-based attacks, and transfer-based attacks

Effectiveness and safety of auricular acupuncture on adjuvant analgesia in patients with total knee arthroplasty: a randomized sham-controlled trial

ObjectiveThis study aimed to evaluate the effectiveness and safety of auricular acupuncture (AA) on postoperative analgesia, the degree of postoperative nausea, and the effect of inflammation after total knee arthroplasty (TKA).MethodsThis was a single-center, placebo-controlled, randomized clinical trial. In total, 96 patients were randomly divided into an AA group with an indwelling intradermal needle (n = 48) and a sham auricular acupuncture (SAA) group with a non-penetrating placebo needle (n = 48). Intra-spinal anesthesia was adopted in both groups during surgery, and an epidural analgesic pump was implanted after surgery for 48 h. The primary outcome was the post-surgery visual analog score (VAS) of resting and movement states (at 6, 12 h and 1, 2, 3, 5, and 7 days). The secondary outcomes included additional doses of analgesic injection during the treatment, C-reactive protein (CRP) levels, erythrocyte sedimentation rate (ESR), and white blood cell (WBC) count on the 1st, 3rd, and 7th day after the operation, nausea on the 1st, 2nd, and 3rd day after the operation, the Hospital for Special Surgery Knee Score (HSS) on the 2nd and 12th week after the operation, and adverse events.ResultsThe VAS in the AA group at 6 h, 12 h, 2, 3, and 5 days after surgery were lower than those of the SAA group (p < 0.05). Among the secondary outcomes, the total dose of additional analgesic injection after surgery in the AA group was lower than that in the SAA group (p < 0.05). The serum CRP on the 1st day after operation in the AA group was lower than that in the SAA group (p < 0.05). The degree of nausea on 2nd day after surgery in the AA group was lower than that in the SAA group (p < 0.05). There was no significant difference in other outcomes (p > 0.05).ConclusionIn this study, AA was shown to be an effective and safe complementary and alternative therapy for pain relief after TKA, which was able to reduce the total postoperative dose of additional painkillers, decrease serum CRP 1 day after surgery, and improve the degree of postoperative nausea.Clinical trial registrationwww.chictr.org.cn, ChiCTR2100054403

Hormonal regulation of ovarian bursa fluid in mice and involvement of aquaporins.

In rodent species, the ovary and the end of oviduct are encapsulated by a thin membrane called ovarian bursa. The biological functions of ovarian bursa remain unexplored despite its structural arrangement in facilitating oocytes transport into oviduct. In the present study, we observed a rapid fluid accumulation and reabsorption within the ovarian bursa after ovarian stimulation (PMSG-primed hCG injection), suggesting that the ovarian bursa might play an active role in regulating local fluid homeostasis around the timing of ovulation. We hypothesized that the aquaporin proteins, which are specialized channels for water transport, might be involved in this process. By screening the expression of aquaporin family members (Aqp1-9) in the ovarian tissue and isolated ovarian bursa (0, 1, 2 and 5 h after hCG injection), we found that AQP2 and AQP5 mRNA showed dynamic changes after hCG treatment, showing upregulation at 1-2 h followed by gradually decrease at 5 h, which is closely related with the intra-bursa fluid dynamics. Further immunofluorescence examinations of AQP2 and AQP5 in the ovarian bursa revealed that AQP2 is specifically localized in the outer layer (peritoneal side) while AQP5 localized in the inner layer (ovarian side) of the bursa, such cell type specific and spatial-temporal expressions of AQP2 and 5 support our hypothesis that they might be involved in efficient water transport through ovarian bursa under ovulation related hormonal regulation. The physiological significance of aquaporin-mediated water transport in the context of ovarian bursa still awaits further clarification

Coupling and Coordination Relationship between Livelihood Capital and Livelihood Stability of Farmers in Different Agricultural Regions

Sustainable livelihood of farmers is the key to rural revitalization. The purpose of this study was to establish livelihood capital cultivation models suitable for farmers in different agricultural regions and to enhance the sustainability of farmers’ livelihoods by selecting four agricultural regions (suburban agriculture, intensive agriculture, plain field agriculture, and mountain agriculture) and 1025 rural households and employing Participatory Rural Appraisal (PRA) to systematically analyze the characteristics of livelihood capital and livelihood stability of farmers in different agricultural regions and the coupling coordination relationship between them based on a Sustainable Livelihood Framework (SLF). The results show that: (1) The average household livelihood capital is highest in intensive agricultural regions and lowest in mountain agricultural regions. (2) Farmers in suburban agricultural regions have a variety of sources of income; thus, the livelihood stability is the highest. while it is lowest in intensive agricultural regions. (3) The coupling coordination degree of livelihood capital and livelihood stability in suburban agricultural regions and plain field agricultural regions is primary coordination, while in intensive agricultural regions and mountain agricultural regions, livelihood capital and stability are slightly out of balance

Coupling and Coordination Relationship between Livelihood Capital and Livelihood Stability of Farmers in Different Agricultural Regions

Sustainable livelihood of farmers is the key to rural revitalization. The purpose of this study was to establish livelihood capital cultivation models suitable for farmers in different agricultural regions and to enhance the sustainability of farmers’ livelihoods by selecting four agricultural regions (suburban agriculture, intensive agriculture, plain field agriculture, and mountain agriculture) and 1025 rural households and employing Participatory Rural Appraisal (PRA) to systematically analyze the characteristics of livelihood capital and livelihood stability of farmers in different agricultural regions and the coupling coordination relationship between them based on a Sustainable Livelihood Framework (SLF). The results show that: (1) The average household livelihood capital is highest in intensive agricultural regions and lowest in mountain agricultural regions. (2) Farmers in suburban agricultural regions have a variety of sources of income; thus, the livelihood stability is the highest. while it is lowest in intensive agricultural regions. (3) The coupling coordination degree of livelihood capital and livelihood stability in suburban agricultural regions and plain field agricultural regions is primary coordination, while in intensive agricultural regions and mountain agricultural regions, livelihood capital and stability are slightly out of balance

Longitudinal hydrodynamic characteristics in reservoir tributary embayments and effects on algal blooms.

Three Gorges Reservoir (TGR) is one of the largest man-made lakes in the world. Since the impoundment in 2003, however, algal blooms have been often observed in the tributary embayments. To control the algal blooms, a thorough understanding of the hydrodynamics (e.g., flow regime, velocity gradient, and velocity magnitude and direction) in the tributary embayments is particularly important. Using a calibrated three-dimensional hydrodynamic model, we carried out a hydrodynamic analysis of a typical tributary embayment (i.e., Xiangxi Bay) with emphasis on the longitudinal patterns. The results show distinct longitudinal gradients of hydrodynamics in the study area, which can be generally characterized as four zones: riverine, intermediate, lacustrine, and mainstream influenced zones. Compared with the typical longitudinal zonation for a pure reservoir, there is an additional mainstream influenced zone near the mouth due to the strong effects of TGR mainstream. The blooms are prone to occur in the intermediate and lacustrine zones; however, the hydrodynamic conditions of riverine and mainstream influence zones are not propitious for the formation of algal blooms. This finding helps to diagnose the sensitive areas for algal bloom occurrence

Analysis of Chemical Composition Characteristics and Source of PM2.5 under Different Pollution Degrees in Autumn and Winter of Liaocheng, China

Analysis of chemical composition characteristics of PM2.5 under different pollution degrees can reveal the changes of pollution sources. In order to make clear the evolution process of PM2.5 compositions in autumn and winter, PM2.5 samples were continuously collected and analyzed at Liaocheng city, China. The collected samples were classified as clean days (CLD), mild-moderate pollution days (MMD) and severe-serious pollution days (SSD). It was concluded that with the increase of pollution degrees, the concentrations of water-soluble ions and carbon components increased significantly, while elements only increased slightly. In addition, as the pollution degrees increased, the percentage of NO3−, SO42− and NH4+ increased significantly, from 23.0% in CLD to 49.0% in SSD, while the percentage of other components decreased, especially crust material. The PMF analyzed results showed that secondary transformation (36.7%), combustion sources (20.4%), secondary organic aerosols (SOA) (11.7%), vehicle sources (11%), dust (10.5%) and industrial processes (9.7%) were the main sources of PM2.5 during autumn and winter in Liaocheng. The contribution of secondary transformation reached 57% at the SSD level, which indicated that it was the main reason for the increase of PM2.5 concentrations. The air mass mainly came from five paths to Liaocheng. The secondary transformation contribution of the air mass with short transmission distance was higher, while the contribution of the dust was higher from the long distance