Airworthiness Compliance Verification Method Based on Simulation of Complex System

AbstractA study is conducted on a new airworthiness compliance verification method based on pilot-aircraft-environment complex system simulation. Verification scenarios are established by “block diagram” method based on airworthiness criteria. A pilot-aircraft-environment complex model is set up and a virtual flight testing method based on connection of MATLAB/Simulink and Flightgear is proposed. Special researches are conducted on the modeling of pilot manipulation stochastic parameters and manipulation in critical situation. Unfavorable flight factors of certain scenario are analyzed, and reliability modeling of important system is researched. A distribution function of small probability event and the theory on risk probability measurement are studied. Nonlinear function is used to depict the relationship between the cumulative probability and the extremum of the critical parameter. A synthetic evaluation model is set up, modified genetic algorithm (MGA) is applied to ascertaining the distribution parameter in the model, and a more reasonable result is obtained. A clause about vehicle control functions (VCFs) verification in MIL-HDBK-516B is selected as an example to validate the practicability of the method

A multicentre study on the clinical characteristics of newborns infected with coronavirus disease 2019 during the omicron wave

ObjectiveTo investigate the clinical characteristics and outcomes of newborns infected with coronavirus disease 2019 (COVID-19) during the Omicron wave.MethodsFrom December 1, 2022, to January 4, 2023, clinical data were collected from neonates with COVID-19 who were admitted to 10 hospitals in Foshan City, China. Their epidemiological histories, clinical manifestations and outcomes were analysed. The neonates were divided into symptomatic and asymptomatic groups. The t test or χ2 test was used for comparisons between groups.ResultsA total of 286 children were diagnosed, including 166 males, 120 females, 273 full-term infants and 13 premature infants. They were 5.5 (0–30) days old on average when they were admitted to the hospital. These children had contact with patients who tested positive for COVID-19 and were infected through horizontal transmission. This study included 33 asymptomatic and 253 symptomatic patients, among whom 143 were diagnosed with upper respiratory tract infections and 110 were diagnosed with pneumonia. There were no severe or critical patients. Fever (220 patients) was the most common clinical manifestation, with a duration of 1.1 (1–6) days. The next most common clinical manifestations were cough with nasal congestion or runny nose (4 patients), cough (34 patients), poor appetite (7 patients), shortness of breath (15 patients), and poor general status (1 patient). There were no significant abnormalities in routine blood tests among the neonates infected with COVID-19 except for mononucleosis. However, compared with the asymptomatic group, in the symptomatic group, the leukocyte and neutrophil granulocyte counts were significantly decreased, and the monocyte count was significantly increased. C-reactive protein (CRP) levels were significantly increased (≥10 mg/L) in 9 patients. Myocardial enzyme, liver function, kidney function and other tests showed no obvious abnormalities.ConclusionsIn this study, neonates infected with the Omicron variant were asymptomatic or had mild disease. Symptomatic patients had lower leucocyte and neutrophil levels than asymptomatic patients

K-Modulated Co Nanoparticles Trapped in La-Ga-O as Superior Catalysts for Higher Alcohols Synthesis from Syngas

Owing to the outstanding catalytic performance for higher alcohol synthesis, Ga-Co catalysts have attracted much attention. In view of their unsatisfactory stability and alcohol selectivity, herein, K-modulated Co nanoparticles trapped in La-Ga-O catalysts were prepared by the reduction of La1−xKxCo0.65Ga0.35O3 perovskite precursor. Benefiting from the atomic dispersion of all the elements in the precursor, during the reduction of La1−xKxCo0.65Ga0.35O3, Co nanoparticles could be confined into the K-modified La-Ga-O composite oxides, and the confinement of La-Ga-O could improve the anti-sintering performance of Co nanoparticles. In addition, the addition of K modulated parts of La-Ga-O into La2O3, which ameliorated the anti-carbon deposition performance. Finally, the addition of K increased the dispersion of cobalt and provided more electron donors to metallic Co, resulting in a high activity and superior selectivity to higher alcohols. Benefiting from the above characteristics, the catalyst possesses excellent activity, good selectivity, and superior stability

Molecular characteristics of<i> IGF</i> and<i> IGF1R</i> genes and their potential roles on longevity in two scallops with distinct lifespans

Bay scallops are commercially important bivalve species for aquaculture worldwide, but the serious inbreeding depression is decreasing their production. Some interspecific hybrids of bay scallops (Argopecten irradians irradians) and Peruvian scallops (A. purpuratus) exhibit longer lifespan and significantly larger size for high yield, which may result from the longevity genes of Peruvian scallops. Insulin-like growth factor (IGF) system, as the conspicuous entry point of insulin/insulin-like growth factor signal (IIS) pathway, regulates various cellular processes including growth, autophagy, aging and longevity, but its roles remain unexplored in marine animals. In this study, we separately cloned a unique IGF2 (ApIGF2 and AiIGF2) and IGF1R (ApIGF1R and AiIGF1R) for the first time from two closely related Argopecten scallops with distinct lifespans and characterized for their ability to regulate longevity. Sequence analysis demonstrated that there were six-span transmembrane domains located at the additional extension of C-terminus special to AiIGF2, which appeared to relate to the differences in post translational processing. The amino acid variation (Y247) in TyrKc domain may be a key site affecting ApIGF1R kinase activity for longevity. Spatiotemporal expression of IGF2 and IGF1R during development and aging showed that the mantle and gonad are representative tissues for aging in scallops. The dietary restriction assay revealed the beneficial effects of attenuated IGF2 and IGF1R levels on longevity in scallops. The invigorated IGF1R conferred DNA repair and prosurvival properties to Peruvian scallops for radio-resistance after acute radioresistance. Inhibition of AiIGF1R upregulated the expression of senescence-associated genes (PENT, FoxO, CAT, Mn-SOD) and antioxidant enzyme activities, and suppressed the senescence marker beta-GAL activity, indicating that IGF1R was a crucial regulator for longevity in scallops. Collectively, our work would bring us closer to understanding the longevity mechanism mediated by IGF system and breeding larger and long-lived hybrids for the sustainable development of aquaculture

Potential roles of MEK1 on aging in Argopecten scallops

Dual specificity mitogen-activated protein kinase kinase 1 (MEK1) has been found to regulate aging through the Ras/Raf/MEK/ERK cascade in terrestrial animals. However, few reports have focused on MEK1 promoting aging in marine bivalves. In this study, we aimed to examine the potential roles of MEK1 in the regulation of aging in two Argopecten scallops, the bay scallop A. irradians and the Peruvian scallop A. purpuratus, which are closely related but with distinct lifespan. The complete ORFs of AiiMEK1 and ApuMEK1 were both 1209 bp, encoding 403 identical amino acids but with 41 synonymous SNPs, which may have contributed to the different activities of MEK1 in two scallops. Nutrient restriction, one of the most effective non-genetic means of promoting life span, significantly inhibit the expression of AiiMEK1 and ApuMEK1. The response in hepatopancreas of A. irradians to nutrient restriction was more persistently than that in A. purpuratus. RNAi of AiiMEK1 significantly increased the expression of its downstream genes known to favor longevity, such as FoxO and SOD, while decreased the expression of ERK1/2 and the key genes in the mTOR signaling pathway, as well as the beta-GAL activity (a marker for senescence). These results indicated that AiiMEK1 may play a negative role in longevity through Ras/Raf/MEK/ERK pathway. Our results may provide new perspective for understanding of the conservative functions of MEK1 in regulation of aging in animals and benefit the genetic selection of scallops

Hybrid sterility in hermaphroditic Argopecten scallops: Mutated mitochondrial genes and abnormal expression of nuclear genes

Bay scallops (Argopecten irradians) are a commercially important bivalve species for fisheries and aquaculture in China, the USA, Peru and Chile, but their small size and serious inbreeding depression restrict the sustainable development of their aquaculture. We successfully hybridized bay scallops with Peruvian scallops (Argopecten purpuratus), and the F1 hybrids showed significant heterosis in growth, but the majority of them were sterile. Nevertheless, Argopecten scallops are typical hermaphroditic animals, resulting in a low proportion of interspecific hybrids. Hybrid sterility restricts the utilization of Argopecten scallop resources and causes reproductive isolation in speciation. However, the underlying mechanism of hybrid sterility remains unexplored in hermaphroditic scallops. In this study, we investigated the mechanism of hybrid sterility in hermaphroditic Argopecten scallops by examining mutations in mitochondrial genes and the expression of nuclear genes. Our results showed that the ATP content in the gonads of F1 hybrid scallops was significantly lower than that in their parents, indicating that energy deficiency may be an immediate cause of sterility in F1 hybrid scallops. Thirteen SNPs were detected in five mitochondrial genes of F1 hybrids, and 92.3% of which were transitions that could change the hydrophobicity of amino acids and protein structures, and the allele frequencies of the SNP loci were significantly different between sterile hybrids and fertile scallops. Abnormal interaction between the mitochondrial and nuclear genes might contribute to hybrid sterility through the following pathways: (1) inhibition of oocyte maturation by enhanced expression of Mfn2; (2) cell cycle arrest in G1 phase of oocytes by inhibited expression of CDK2; (3) cell apoptosis induced by mitochondrial apoptosis; (4) insufficient energy supply from abnormal mitochondria, and (5) mitochondrial dysfunction resulting from abnormal expression of other nuclear genes. The present results provide more information for understanding the mechanism of hybrid sterility in hermaphroditic animals and benefit extensive hybrid breeding

Constructing Abundant Oxygen-Containing Functional Groups in Hard Carbon Derived from Anthracite for High-Performance Sodium-Ion Batteries

Hard carbon is regarded as one of the greatest potential anode materials for sodium-ion batteries (SIBs) because of its affordable price and large layer spacing. However, its poor initial coulombic efficiency (ICE) and low specific capacity severely restrict its practical commercialization in SIBs. In this work, we successfully constructed abundant oxygen-containing functional groups in hard carbon by using pre-oxidation anthracite as the precursor combined with controlling the carbonization temperature. The oxygen-containing functional groups in hard carbon can increase the reversible Na+ adsorption in the slope region, and the closed micropores can be conducive to Na+ storage in the low-voltage platform region. As a result, the optimal sample exhibits a high initial reversible sodium storage capacity of 304 mAh g−1 at 0.03 A g−1, with an ICE of 67.29% and high capacitance retention of 95.17% after 100 cycles. This synergistic strategy can provide ideas for the design of high-performance SIB anode materials with the intent to regulate the oxygen content in the precursor