This paper investigates the relationship between the frequency support by voltage-source converter based high-voltage direct current (VSC-HVDC) systems and the deloaded wind power operation ...considering the frequency stability constraints. The frequency stability is incorporated as additional constraints in the optimal power flow (OPF) analysis. The reserve capacity of the wind power plants should be provided for frequency support, which requires wind power output suppression during the steady-state. On the contrary, this wind output curtailment is unnecessary if the frequency stability constraints can be satisfied by the fast frequency controller of the VSC-HVDC system. The optimal wind power deload ratio can be determined by the OPF calculation. A hybrid AC/VSC-HVDC system model is designed based on the IEEE 39-bus system. The inertia emulation control (IEC) method is applied to the slack converter for the primary frequency support. Sensitivity analysis on the frequency stability constraints, and the capacities of wind power plants and HVDC systems are carried out. It is validated that the primary frequency support of VSC-HVDC systems can reduce the wind power output suppression.
This paper proposes an optimization method for wind power output curtailment based on optimal power flow (OPF) analysis. The wind curtailment ratio is incorporated as a controllable variable in the ...OPF formulation. A voltage-source converter based high-voltage direct current (VSC-HVDC) system is installed in a power system model considering large-scale wind farm integration. Inertia emulation control (IEC) is implemented for the VSC-HVDC system. When a disturbance occurs, the VSC-HVDC system can participate in the AC grid frequency stabilization by supplying active power. However, the utilization of the active power in the VSC-HVDC system results in DC grid voltage fluctuation. This fluctuation can be reduced if the IEC frequency control can be replaced by wind-side frequency regulation. However, wind-based frequency control requires wind output suppression to obtain the reserve capacity. This is undesirable for minimizing the fuel cost objective function. In this context, the novel point of this paper is to determine the optimal wind output curtailment considering both the fuel cost objective function and the DC voltage constraints by the OPF analysis. Considering the DC voltage reference deviation occurred by the IEC, the deviation range of the DC voltage reference is limited as an inequality constraint to prevent infeasible DC voltage fluctuations. Based on this approach, the advantage of wind output suppression can be analyzed from the DC voltage perspective. Sensitivity analysis on the DC voltage constraints, wind power plant capacity, and VSC-HVDC system capacity is performed to prove the effectiveness of the proposed method.
Viral infection during pregnancy has been correlated with increased frequency of autism spectrum disorder (ASD) in offspring. This observation has been modeled in rodents subjected to maternal immune ...activation (MIA). The immune cell populations critical in the MIA model have not been identified. Using both genetic mutants and blocking antibodies in mice, we show that retinoic acid receptor–related orphan nuclear receptor gamma t (RORγt)–dependent effector T lymphocytes for example, T helper 17 (TH17) cells and the effector cytokine interleukin-17a (IL-17a) are required in mothers for MIA-induced behavioral abnormalities in offspring. We find that MIA induces an abnormal cortical phenotype, which is also dependent on maternal IL-17a, in the fetal brain. Our data suggest that therapeutic targeting of TH17 cells in susceptible pregnant mothers may reduce the likelihood of bearing children with inflammation-induced ASD-like phenotypes.
The nitric oxide (NO) and cyclooxygenase (COX) pathways share a number of similarities. Nitric oxide is the mediator generated from the NO synthase (NOS) pathway, and COX converts arachidonic acid to ...prostaglandins, prostacyclin, and thromboxane A(2). Two major forms of NOS and COX have been identified to date. The constitutive isoforms critically regulate several physiological states. The inducible isoforms are overexpressed during inflammation in a variety of cells, producing large amounts of NO and prostaglandins, which may underlie pathological processes. The cross-talk between the COX and NOS pathways was initially reported by Salvemini and colleagues in 1993, when they demonstrated in a series of in vitro and in vivo studies that NO activates the COX enzymes to produce increased amounts of prostaglandins. Those studies led to the concept that COX enzymes represent important endogenous "receptor" targets for amplifying or modulating the multifaceted roles of NO in physiology and pathology. Since then, numerous studies have furthered our mechanistic understanding of these interactions in pathophysiological settings and delineated potential clinical outcomes. In addition, emerging evidence suggests that the canonical nitroxidative species (NO, superoxide, and/or peroxynitrite) modulate biosynthesis of prostaglandins through non-COX-related pathways. This article provides a comprehensive state-of-the art overview in this area.
All cells rely on nutrients to supply energy and carbon building blocks to support cellular processes. Over time, eukaryotes have developed increasingly complex systems to integrate information about ...available nutrients with the internal state of energy stores to activate the necessary processes to meet the immediate and ongoing needs of the cell. One such system is the network of soluble and membrane-associated inositol phosphates that coordinate the cellular responses to nutrient uptake and utilization from growth factor signaling to energy homeostasis. In this review, we discuss the coordinated interactions of the inositol polyphosphates, inositol pyrophosphates, and phosphoinositides in major metabolic signaling pathways to illustrate the central importance of the inositol phosphate signaling network in nutrient responses.
The CryoPreservation Media (CPM) for mouse sperm using raffinose and skim milk have been improved by adding either monothioglycerol (MTG) or l-glutamine to reduce the oxidative damage during sperm ...freezing and thawing. The CARD-CPM utilizing l-glutamine, but not MTG, has been widely used to meet the rising demand for cryopreservation of genetically modified mice, as the CARD method also improved sperm capacitation and in vitro fertilization (IVF). However, the viability of sperm frozen in the CARD-CPM is highly variable, indicating a room for improvement. To develop a more dependable technique for mouse sperm cryopreservation, we investigate whether combining MTG and l-glutamine in the CPM (MG-CPM) can produce a synergistic impact on sperm thawing and IVF rate. We found that MG-CPM reduced the incidence of infertility and increased the IVF success rate. Therefore, cryopreservation of mouse sperm in MG-CPM is a reliable method to ensure embryo generation from frozen sperm.
In this paper, we propose a new approach to detect Deepfakes generated through the generative adversarial network (GANs) model via an algorithm called DeepVision to analyze a significant change in ...the pattern of blinking, which is a voluntary and spontaneous action that does not require conscious effort. Human eye blinking pattern has been known to significantly change according to the person's overall physical conditions, cognitive activities, biological factors, and information processing level. For example, an individual's gender or age, the time of day, or the person's emotional state or degree of alertness can all influence the pattern. As a result, Deepfakes can be determined through integrity verification by tracking significant changes in the eye blinking patterns in deepfakes by means of a heuristic method based on the results of medicine, biology, and brain engineering research, as well as machine learning and various algorithms based on engineering and statistical knowledge. This means we can perform integrity verification through tracking significant changes in the eye blinking pattern of a subject in a video. The proposed method called DeepVision is implemented as a measure to verify an anomaly based on the period, repeated number, and elapsed eye blink time when eye blinks were continuously repeated within a very short period of time. DeepVision accurately detected Deepfakes in seven out of eight types of videos (87.5% accuracy rate), suggesting we can overcome the limitations of integrity verification algorithms performed only on the basis of pixels.
Lymphocyte homing, which contributes to inflammation, has been studied extensively in the small intestine, but there is little known about homing to the large intestine, the site most commonly ...affected in inflammatory bowel disease. GPR15, an orphan heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptor, controlled the specific homing of T cells, particularly FOXP3⁺ regulatory T cells (T regs ), to the large intestine lamina propria (LILP). GPR15 expression was modulated by gut microbiota and transforming growth factor-ß1, but not by retinoic acid. GPR15-deficient mice were prone to develop more severe large intestine inflammation, which was rescued by the transfer of GPR15-sufficient T regs . Our findings thus describe a T cell-homing receptor for LILP and indicate that GPR15 plays a role in mucosal immune tolerance largely by regulating the influx of T regs .
Abstract Insulin resistance and other features of the metabolic syndrome are increasingly recognized for their effects on cognitive health. To ascertain mechanisms by which this occurs, we fed mice a ...very high fat diet (60% kcal by fat) for 17 days or a moderate high fat diet (HFD, 45% kcal by fat) for 8 weeks and examined changes in brain insulin signaling responses, hippocampal synaptodendritic protein expression, and spatial working memory. Compared to normal control diet mice, cerebral cortex tissues of HFD mice were insulin-resistant as evidenced by failed activation of Akt, S6 and GSK3β with ex-vivo insulin stimulation. Importantly, we found that expression of brain IPMK, which is necessary for mTOR/Akt signaling, remained decreased in HFD mice upon activation of AMPK. HFD mouse hippocampus exhibited increased expression of serine-phosphorylated insulin receptor substrate 1 (IRS1-pS616 ), a marker of insulin resistance, as well as decreased expression of PSD-95, a scaffolding protein enriched in post-synaptic densities, and synaptopodin, an actin-associated protein enriched in spine apparatuses. Spatial working memory was impaired as assessed by decreased spontaneous alternation in a T-maze. These findings indicate that HFD is associated with telencephalic insulin resistance and deleterious effects on synaptic integrity and cognitive behaviors.
► Nitric oxide regulates prostaglandin synthesis. ► Nitric oxide activates cyclooxygenase2 activity via S-nitrosylation. ► Peroxinitrite inactivates cyclooxygenase1/2 via Tyrosine nitration. ► ...Interaction of Peroxinitrite and heme in cyclooxygenase can activate their activity.
The biosynthesis of nitric oxide (NO) and prostaglandin share many similarities. Two major forms of nitric oxide synthase (NOS) and cyclooxygenase (COX) have been identified: constitutive versus inducible. In general, the constitutive form functions in housekeeping and physiologic roles whereas the inducible form is up-regulated by mitogenic or inflammatory stimuli and is responsible for pathophysiological responses. The cross talk between the COX and NOS pathways was initially reported in 1993 and since then, numerous studies have been undertaken to delineate the functional consequences of this interaction as well as the potential mechanism by which each pathway interacts. This review will focus in particular on recent advances in this field that extend our understanding of these two pathways under various systems.
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