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(1) Background: Weaning is a challenging and stressful event in the pig's life, which disrupts physiological balance and induces oxidative stress. Microbiota play a significant role during the weaning process in piglets. Therefore, this study aimed to investigate key gut microbiota and metabolites associated with weaning stress in piglets. (2) Methods: A total of ten newborn piglet littermates were randomly assigned to two groups: S (suckling normally) and W (weaned at 21 d; all euthanized at 23 d). Specimens of the cecum were dehydrated with ethanol, cleared with xylene, embedded in paraffin, and cut into 4 mm thick serial sections. After deparaffinization, the sections were stained with hematoxylin and eosin (H&E) for morphometric analysis. Cecal metagenomic and liver LC-MS-based metabolomics were employed in this study. Statistical comparisons were performed by a two-tailed Student's t-test, and p < 0.05 indicated statistical significance. (3) Results: The results showed that weaning led to intestinal morphological damage in piglets. The intestinal villi of suckling piglets were intact, closely arranged in an orderly manner, and finger-shaped, with clear contours of columnar epithelial cells. In contrast, the intestines of weaned piglets showed villous atrophy and shedding, as well as mucosal bleeding. Metagenomics and metabolomics analyses showed significant differences in composition and function between suckling and weaned piglets. The W piglets showed a decrease and increase in the relative abundance of Bacteroidetes and Proteobacteria (p < 0.05), respectively. The core cecal flora in W piglets were Campylobacter and Clostridium, while those in S piglets were Prevotella and Lactobacillus. At the phylum level, the relative abundance of Bacteroidetes significantly decreased (p < 0.05) in weaned piglets, while Proteobacteria significantly increased (p < 0.05). Significant inter-group differences were observed in pathways and glycoside hydrolases in databases, such as the KEGG and CAZymes, including fructose and mannose metabolism, salmonella infection, antifolate resistance, GH135, GH16, GH32, and GH84. We identified 757 differential metabolites between the groups through metabolomic analyses—350 upregulated and 407 downregulated (screened in positive ion mode). In negative ion mode, 541 differential metabolites were identified, with 270 upregulated and 271 downregulated. Major differential metabolites included glycerophospholipids, histidine, nitrogen metabolism, glycine, serine, threonine, β-alanine, and primary bile acid biosynthesis. The significant differences in glycine, serine, and threonine metabolites may be potentially related to dysbiosis caused by weaning stress. Taken together, the identification of microbiome and metabolome signatures of suckling and weaned piglets has paved the way for developing health-promoting nutritional strategies, focusing on enhancing bacterial metabolite production in early life stages. [ABSTRACT FROM AUTHOR]

To analyze quasi‐periodic signals (with time‐varying complex amplitudes/frequencies) typically contained in geophysical observables is a quest that has seen continual advances in numerical techniques over the decades. In this study, based on transient z‐pole estimation (in Hankel matrices), a state‐space analysis referred to as Hankel Spectral Analysis (HSA) was developed. Based on the Hankel total least squares and incorporating truncated singular value decomposition and its shift‐invariant property, the HSA aims to decompose the closely spaced sinusoids robustly and orthogonally. Upon using a sliding windows process, the HSA can be used for decomposing and analyzing quasi‐periodic signals, in the support of consecutive parameter spectra {Ai, fi, θi}. Based on a series of experiments, we first confirmed the superiority of the HSA for decomposing different signal constituents (e.g., amplitude‐frequency modulation, mutation, and episodic signals). In real applications, as examples, we use HSA to analyze the polar motion (PM) and Earth's dynamic oblateness (ΔJ2). For the PM, we obtained the time‐varying Chandler wobble (CW) and Annual wobble, and first confirmed that there are four phase jumps in the CW since the 1900s; we find that all of those phase jumps are synchronized by the sharp decrease of Chandler intensity and period, and their random excitation mechanism was discussed. For the ΔJ2, the 18.6 and 10.5 years signals were re‐extracted, and we found that its interannual‐to‐decadal oscillations contribute to multiple global gravity anomalies. These results indicate the great potential of the HSA in decomposing and extracting the recorded periodic/quasi‐periodic signals from geophysical observations. Plain Language Summary: In signal analysis, the refined extracting of the periodic and quasi‐periodic signals remains a considerable challenge. In this study, we propose a powerful time‐series separator, the Hankel Spectral Analysis (HSA), which supports instant structured detection that traditional methods cannot afford. We have designed multiple sets of simulations to show the HSA's well‐restored ability for various and complex quasi‐periodic signals. Although the HSA has some significant advantages, it has two fundamental limitations: (a) it is applicable only to data series which are physically constituted by a sum of harmonic components; (b) the number of harmonic components needs to know beforehand. In the real application, we focus on the study of polar motion (PM) and the Earth's dynamic oblateness (ΔJ2). Here, we mainly attempted to resolve their recent disputes about the Chandler wobbles (CW) phase jumps in PM and the long periodic signal in ΔJ2. Subsequently, the origins of CW phase jumps are re‐examined; and our results show that there is a particular consistency between the four‐phase jump events and the valleys of amplitude and period. In addition, we re‐extracted the ∼18.6 and 10.5 years signals in ΔJ2 and found that the famous "1998 anomaly" related to the fluctuations on interannual‐decadal timescales. Key Points: Hankel Spectrum Analysis is proposed for more exactly decomposing and parameterizing signals with time‐varying amplitudes/frequenciesMultiple phase jumps of the Chandler wobble accompanied by sudden drops in instantaneous amplitude and period are detectedWe access the Earth's oblateness ΔJ2 of the residual ∼18.6 years tidal signal, ∼10.5 years signal, and multiple global gravity anomaly peaks [ABSTRACT FROM AUTHOR]

Fractured reservoirs are highly heterogeneous in both matrix and fracture properties, which results in significant variations in well production. Assessing and quantifying the influence of fractures on fluid flow is essential for developing unconventional reservoirs. The complicated effects of fractures in unconventional fractured reservoirs on fluid flow highly depend on fracture geometry, fracture distribution, and fracture properties, which can be reflected in pressure transient testing. The biggest challenge lies in delineating the pre-existing natural fracture distribution pattern, density, azimuth, and connectivity. Using the advanced finite element method, this paper builds a finely characterized near-wellbore model to numerically simulate the pressure transient testing process in naturally fractured reservoirs and further evaluates fracture-related effects to obtain a more accurate solution. First, the numerical program is benchmarked by the analytical solutions and numerical results of Eclipse. Next, different fracture models with single fractures or fracture networks are set up to investigate the effects of fracture parameters numerically (e.g., fracture location, fracture dip angle, fracture spacing, the ratio of fracture permeability to matrix permeability, fracture network orientation, horizontal fracture distribution, etc.) on pressure transient behaviors in naturally fractured reservoirs. Velocity and pressure profiles are presented to visualize and analyze their effects, and new features in the flow regimes of the derivative plots of the bottom-hole pressure are identified and discussed. Finally, based on geological and geophysical data, including image logs, core descriptions, wireline logs, and seismic and well test data, a practical fractured model of the Dalwogan 2 well in the Surat basin is built, analyzed, and compared with homogenous and measured data. The results show significance in characterizing the complex fracture networks in near-wellbore models of unconventional fractured reservoirs. [ABSTRACT FROM AUTHOR]

The Tonga volcano erupted on 15 January 2022, at 04:15:45 UTC, which significantly influenced the atmosphere and space environment, at the same time, an unprecedented opportunity to monitor ionospheric anomalies is provided by its powerful eruption. In current studies of traveling ionospheric disturbance (TID) triggered by the 2022 Tonga volcanic eruption, the particular phenomenon of ionospheric disturbances in various parts of the world has not been reasonably explained, and the vertical ionospheric disturbances are still not effectively detected. In this paper, we calculate the high-precision slant total electron content (STEC) from more than 3000 ground-based GPS stations distributed around the world, then we obtain the radio occultation (RO) data from near-field COSMIC-2 profiles and investigate the horizontal TID and the vertical ionospheric disturbances by the singular spectrum analysis (SSA). Horizontal TID propagation captured by GPS STEC results indicates that acoustic-gravity waves dominate the energy input at the beginning of the ionospheric disturbance with an approximate speed of 1050 m/s initially. With the dissipation of the shock energy, lamb waves become a dominant mode of ionospheric disturbances, moving at a more stable speed of about 326 m/s to a range of 16,000 km beyond the far-field. Local characteristics are evident during the disturbance, such as the ionospheric conjugation in Australia and the rapid decay of TID in Europe. The shock-Lamb-tsunami waves' multi-fluctuation coupling is recorded successively from the COSMIC-2 RO observation data. The shock and Lamb waves can perturb the whole ionospheric altitude. In contrast, the disturbance caused by tsunami waves is much smaller than that of acoustic-gravity waves and Lamb waves. In addition, influenced by the magnetic field, the propagation speed of TID induced by Lamb waves is higher towards the northern hemisphere than towards the southern hemisphere. [ABSTRACT FROM AUTHOR]

The application of novel injection strategies (high-pressure injection, early injection, retarded injection, etc.) in combustion engines has made the wall-wetting problem severer. As the splashed fuel dilutes the lubricating oil, the tribological performance of the cylinder liner–piston ring pair will be affected. In this research, the viscosity and wettability tests were conducted firstly by mixing diesel into lubrication oil. It was found that the dynamic viscosity of the mixture drops with more fuel diluting the oil, and a small quantity of diesel mixed will cause a remarkable decline in lubricant viscosity; also, the contact angle shows a downward trend with the increasing diluting ratio. Then based on several typical diluting ratios, the reciprocating friction tests were carried out to measure the instantaneous friction force of the production ring/liner pair. The experimental results showed that under a mixed lubrication state, the peak friction force of the ring/liner pair occurs around the dead centers, while the minimum force occurs at the middle position of the reciprocating stroke; with more fuel diluting the oil, the bearing capacity of oil film degrades, resulting in the increase of friction force. In addition, the average friction coefficient of the ring/liner pair shows an upward trend with the increasing diluting ratio, and the Stribeck curve moves toward the upper-left, which means the lubrication condition of this pair tends to transit from mixed lubrication to boundary lubrication, causing negative effects on the frictional property of the cylinder liner–piston ring pair. Therefore, the diluting ratio should be controlled under 20%. [ABSTRACT FROM AUTHOR]

Frequency shift islanding detection methods have been widely used in inverter-based distributed generations. Two representatives of such methods, Sandia frequency shift (SFS) and reactive current perturbation (RCP) methods, are investigated in this article. The investigation reveals two main issues with these two methods, i.e., parameter selection scheme for positive feedback gain and current static error. The current parameter selection scheme, in particular, is considered unreliable and inconvenient in this article, for it has not considered the weakening effect of PI regulators on positive feedback and the positive feedback gain is actually obtained by trial and error, which makes it difficult to use such methods well in field environments. In view of these issues, this article proposes a solution that contains an improved method to eliminate current static error and a reliable and convenient parameter selection scheme based on system stability analyses. The final simulations and experiments verify the good performance of the improved method and the parameter selection scheme. [ABSTRACT FROM AUTHOR]

The ubiquitin‐proteasome system is the primary cellular pathway for protein degradation, mediating 80% of intracellular protein degradation. Because of the widespread presence of ubiquitin‐modified protein substrates, ubiquitination can regulate a variety of cellular activities including cell proliferation, apoptosis, autophagy, endocytosis, DNA damage repair, and immune responses. With the continuous generation of genomics data in recent years it has become particularly important to analyze these data effectively and reasonably. Cacybp forms a complex with the E3 ubiquitinated ligase Siah1 to participate in ubiquitination. We analyzed Cacybp‐associated genes using the Gene Expression Omnibus (GEO) and CGGA (Chinese Glioma Genome Atlas) databases and identified 121 differentially expressed genes (DEGs), of which 46 were downregulated and 75 were upregulated. The biological processes, molecular functions, and protein–protein interaction (PPI) network of differential genes were analyzed by Cytoscape software and STRING software. We found no difference in Cacybp expression among different grades of gliomas and there was no significant association between the expression level of Cacybp and the prognosis of patients with glioma in LGG and GBM. © 2019 IUBMB Life, 1–8, 2019 [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The singular spectrum analysis (SSA) method is proposed to detect the ionospheric anomaly preceding great earthquake. • SSA can effectively eliminate the influence of solar-geomagnetic activities. • SSA can detect more obviously anomalous characteristics of seismic-ionospheric coupling effect than traditional methods. Abstract To study seismo-ionospheric coupling, the singular spectrum analysis (SSA) method was introduced to detect ionospheric anomalies preceding great earthquakes. The SSA method was used to decompose the total electronic content (TEC) series, and the reconstructed components (RCs) were combined to obtain the TEC principal components using w-correlation. The background TEC value during the quiet solar-terrestrial environment period was used to calculate the standard deviation, which was subsequently used to determine the upper and lower bounds of the background values. The root-mean-square error of the global ionosphere map (GIM) published by the International GNSS Service (IGS) near the earthquake epicenter was extracted and averaged to obtain the threshold, which was then used to suppress the systematic error effect during the detection of pre-earthquake TEC anomalies process. This new method was used to detect ionospheric anomalies prior to the occurrence of the Mw7.8 Kaikoura earthquake in New Zealand on 13 November 2016 and the Mw6.9 Fukushima earthquake in Japan on 21 November 2016. The TEC data were further analysed with the sliding interquartile range (IQR) method to verify the reliability and feasibility of the SSA. The results showed that the TEC anomalies over these two epicenters were clearly detected on 25 and 28 October and 10 November. Our results showed that compared with IQR, SSA could detect TEC anomalies with a larger magnitude, making TEC anomalies caused by external factors more visible. Furthermore, based on the analysis of the solar-terrestrial environment using the data of F10.7, Dst and Kp indices, it is found that magnetic storms occurred during these three days. To identify and extract potential precursor information on seismo-ionospheric anomalies, the global distribution of TEC anomalous areas with SSA and IQR was also analysed. The results indicated the presence ofobvious anomalous characteristics of the seismic-ionospheric coupling effect in the preparation zones detected by SSA. In addition, the relation between TEC anomaly and Dst index detected by the cross-wavelet analysis indicated that ionospheric anomalies outside the preparation zones detected by IQR were caused by magnetic storms. In contrast, the ranges and amplitudes of TEC anomalies detected by SSA in these zones were much smaller than those with IQR. Overall, these findings demonstrate that SSA can effectively eliminate the effect of solar-geomagnetic activity and extract seismic-ionospheric coupling anomalies. [ABSTRACT FROM AUTHOR]

Short‐term wind‐power forecasting methods like neural networks are trained by empirical risk minimization. The local optimum and overfitting problem is likely to occur in the model‐training stage, leading to the poor ability of reasoning and generalization in the prediction stage. To solve the problem, a model of short‐term wind power forecasting is proposed based on 2‐stage feature selection and a supervised random forest in the paper. First, in data preprocessing, some redundant features can be removed by a variable importance measure method and intimate samples can be selected based on relevant analysis, so that the efficiency of model training and the correlation degree between input and output samples can be enhanced. Second, an improved supervised random forest (RF) methodology is proposed to compose a new RF based on evaluating the performance of each decision tree and restructuring the decision trees. A new index of external validation in correlation with wind speed in numerical weather prediction has been proposed to overcome the shortcomings of the internal validation index that seriously depends on the training samples. The simulation examples have verified the rationality and feasibility of the improvement. Case studies of measured data from a wind farm have shown that the proposed model has a better performance than the original RF, back propagation neural network, Bayesian network, and support vector machine, in aspects of ensuring accuracy, efficiency, and robustness, and especially if there is high rate of noisy data and wind power curtailment duration in the historical data. [ABSTRACT FROM AUTHOR]

This paper first derives a usable formula for frequency shift islanding detection methods on the basis of the parallel R, L, C load and the conclusions in current literature: the angle by which the total output current of the distributed resources (DR) units leads the point of common coupling (PCC) voltage must be conducted to have the same shifting direction as the load admittance angle during the variation of the frequency. According to the formula and multi-DR operation, the scenarios in which the classic frequency shift methods are applied to energy storage converters are analyzed. The results indicate that the setting of the angle by which the energy storage converter current leads the PCC voltage may need to be modified when running state changes. It results in the problems that the classic methods are not applicable for non-unity power factor (non-UPF) control and have to distinguish between generation mode and consumption mode for UPF control. On account of the problems, a coping strategy, i.e., an improved method, is proposed. The analyses indicate that the improved method is applicable in every state. The last simulations and experiments confirm the preceding conclusions. [ABSTRACT FROM AUTHOR]

The ultra-small spacing tunnel is a new tunnel type under the urban engineering environment, which not only has high requirements for deformation and settlement control, but also has great difficulty in construction technology. Since the middle rock pillar is the key part in the design and construction of ultra-small spacing tunnels, to explore the stability of the middle rock pillar in the ultra-small spacing (0-200 mm) subway tunnels, this study examined the Gangding-Shipaiqiao ultra-small spacing tunnels on Guangzhou Metro Line 3 in China by using ABAQUS and theoretical analysis, which mainly involved the plastic zone of the surrounding rock, the stress distribution and skew displacement effect of the middle rock pillar by defining the skew coefficient. The tunnel cross-sections of three different types were optimized, and a simplified calculation method was proposed with the load and ultimate bearing capacity of the middle rock pillar. Results show that the theoretical analysis of the bearing capacity of the middle rock pillar is essentially consistent with the results of numerical calculation. The conclusions obtained in the study are of important theoretical value to provide on-site engineering construction guidance. [ABSTRACT FROM AUTHOR]

Green tide outbreaks caused by overgrowth of Ulva prolifera in the Yellow Sea of China can cause serious ecological stress with concomitant economic hardships, especially to marine fisheries. In this study, short-term effects (14 days) were evaluated using fresh algae U. prolifera (FU), and a 7-day assessment of the effects of decomposing U. prolifera (DU) algal effluent was conducted to determine the effects on the environmental and intestinal microbiota, intestinal transcriptome and mortality of the commercial marine benthic fish, Japanese flounder (Paralichthys olivaceus). The results revealed that algal degradation altered the microbial community structure of fish farm water and fish intestines and increased the relative abundance of the pathogens Flavobacteriaceae in water and Vibrio in fish intestines. Fish intestinal tissue structure appeared to be damaged, as indicated in pathological sections, and transcriptome analysis showed intestinal inflammation after exposure, which may have caused an increase in fish mortality. The degradation of U. prolifera led to a bloom of potential pathogenic bacteria and the inflammation of fish intestines, which resulted in disease in the flounder population that reduced fish harvests and might pose a potential health threat. [Display omitted] • U. prolifera decomposition affected the microbiota in the water and fish intestines. • Potential pathogens Flavobacteriaceae in water significantly increased. • The conditional pathogen Vibrio increased significantly in the intestine of Japanese flounder. • U. prolifera exposure damaged fish intestinal structure and increased mortality. • DEGs related to immunity and inflammation in the intestine changed significantly. [ABSTRACT FROM AUTHOR]

The liver is a multi-functional organ including metabolism, substance synthesis, detoxification, and various immune functions, and its role in immunity has attracted more and more attention. However, research on the liver immune response of fish infected by pathogenic bacteria is currently lacking. In this study, the transcriptomics and proteomics of the liver of Cynoglossus semilaevis infected with Vibrio anguillarum were analyzed. A total of 1470 genes and 497 proteins were differentially expressed in the pairwise comparison of obvious symptoms of infection (HOSG), no obvious symptoms of infection (NOSG) and PBS treatment (CG). Gene ontology and KEGG enrichment pathways analysis showed that differentially expressed genes (DEGs) and differentially expressed proteins (DEPs) were mainly enriched in toll-like receptors (TLRs), complement and coagulation cascades, nucleotide oligomerization domain (NOD)-like receptors (NLRs), mitogen-activated protein kinase (MAPK) and phagosome signaling pathways, which suggested the combined action of the five pathways were significant to enhance the liver immune defense. The combination of transcriptomic and proteomic analysis showed that ITGβ1 , C3 , C5 and MRC1 were significantly up-regulated, which might play an important role in the liver immune response to the recognition of V. anguillarum , inflammatory response and phagocytosis. The transcriptome and proteome data we obtained provide information on some key genes and proteins for further study of the mechanism of liver immune response. [Display omitted] • There were 1470 DEGs and 497 DEPs in C. semilaevis after V. anguillarum infection. • PRRs, MAPK, phagosome and complement pathways in the liver were significantly altered. • Transcriptomic/proteomic analysis showed up-regulation of ITGβ1 , C3 , C5 and MRC1. [ABSTRACT FROM AUTHOR]

GPS radio occultation (RO) technology can fully describe the subtle structure of the ionosphere. This paper discusses the dynamic abnormity observed by the RO data from the Constellation Observing System for Meteorology Ionosphere and Climate (FORMOSAT-3/COSMIC) before the great earthquake case in Concepcion, Chile (27 February 2010, Mw 8.8). Traditional ground-based GPS monitoring was considered as the external conditions and references to the excitation response. Using kriging interpolation, the global Nmf2 map (GNM) was first constructed to study the ionosphere deviation from the normal state. Successively, the ionosphere abnormality in the F2 region (Nmf2), vertical structure (RO profiles), and multiple heights (electron density) of traveling are unfolded. The Nmf2 disturbances in the possibility of seismic influences were excluded from non-seismic noise factors, including the external input (e.g., space weather activity, 15 February) and meteorological events (e.g., lower atmospheric forcing in quiet periods). However, the results show that there were apparent local Nmf2 perturbations for up to 5 h in the epicenter area on 21 and 25 February. The disturbances of the RO profiles and the interaction of other layers of the ionosphere implied the fluctuation signals of prominent long-wavelength fluctuations >50 km in the F layer. The ionospheric fluctuates wildly, and these wave signals considered as the trace of gravity wave propagating upward are mainly distributed at the elevation of 200–300 km. The simultaneous reaction of GNSS TEC further evidenced the potential possibility of acoustic gravity by the COSMIC RO profiles, reflecting the compounding couplings of seismo-ionosphere effects. In terms of the presentation of VLF radiation noise and the aerosol ion clusters, the electromagnetic and chemical channels have been previously completed by DEMETER and Terra/Aqua satellites. These findings implied the great potential of the FORMOSAT-7/COSMIC-2 system (now in the testing phase), with ~5000 soundings to investigate the subtle atmospheric stratification. [ABSTRACT FROM AUTHOR]

The Mw7.9 Alaska earthquake at 09:31:40 UTC on 23 January 2018 occurred as the result of strike slip faulting within the shallow lithosphere of the Pacific plate. Global positioning system (GPS) data were used to calculate the slant total electron contents above the epicenter. The singular spectrum analysis (SSA) method was used to extract detailed ionospheric disturbance information, and to monitor the co-seismic ionospheric disturbances (CIDs) of the Alaska earthquake. The results show that the near-field CIDs were detected 8–12 min after the main shock, and the typical compression-rarefaction wave (N-shaped wave) appeared. The ionospheric disturbances propagate to the southwest at a horizontal velocity of 2.61 km/s within 500 km from the epicenter. The maximum amplitude of CIDs appears about 0.16 TECU (1TECU = 1016 el m−2) near the epicenter, and gradually decreases with the location of sub-ionospheric points (SIPs) far away from the epicenter. The attenuation rate of amplitude slows down as the distance between the SIPs and the epicenter increases. The direction of the CIDs caused by strike-slip faults may be affected by the horizontal direction of fault slip. The propagation characteristics of the ionospheric disturbance in the Alaska earthquake may be related to the complex conditions of focal mechanisms and fault location. [ABSTRACT FROM AUTHOR]

Marine heat waves and extreme high temperature become more frequent and intense in these years, which affected the survival of aquaculture animals. The ridgetail white prawn Exopalaemon carinicauda is an important economic species in eastern China, which has remarkable thermal tolerance. However, there has been little study of its thermal-adaptation mechanisms due to the complex genetic structure and unknown genome. To better understand the molecular mechanisms of E. carinicauda to adapt to the changing temperature, a combination of Illumina-based short reads RNA-seq and single molecule real-time-based full-length transcriptome sequencing was used in this study. In total, 17,212 unigenes from high-quality transcripts of E. carinicauda were generated and 14,663 complete ORFs were detected with an average length of 1980 bp. In addition, the transcriptome profiles of E. carinicauda treated with 34 °C heat stress for 6 and 24 h were analyzed. These differentially expressed genes were primarily enriched in oxidation-reduction process (Gene Ontology enrichment, GO) and the pathways of starch and sucrose metabolism (Kyoto Encyclopedia of Genes and Genomes enrichment, KEGG) after 6 h thermal stress, which indicated that E. carinicauda was suffering the attack by reactive oxygen species. After 24 h thermal stress, these differentially expressed genes were enriched in the pathway of lysosome, glycine, serine and threonine metabolism, fatty acid metabolism (KEGG), which indicated the oxidative stress was decreased. Interestingly, 40 genes for hemocyanin were found to be downregulated after 6 h heat stress, which indicated that the immunocompetence of E. carinicauda decreased after short term thermal stress (6 h). After 24 h thermal stress, E. carinicauda showed transcriptional adaptation to high temperature by upregulating of 11 genes encoding molecular chaperones, including HSP40 and HSP90 which were firstly reported to be related to thermal stress in E. carinicauda. These results promote a better understanding of the thermal-adaptation mechanism of E. carinicauda. Unlabelled Image • Explore the adaptation mechanism of aquaculture animal in coastal area to cope with the thermal stress. • Combine short reads RNA-seq and single molecule full-length transcriptome sequencing to get more reliable results. • Find two novel molecular chaperone to adapt to the thermal stress in crustacean. [ABSTRACT FROM AUTHOR]

Islanding detection methods, based on injecting high-/low-frequency currents or negative sequence fundamental frequency currents and observing the resultant responses, are collectively referred to as irregular current injection methods in this paper. In multi-distributed generation (DG) operation, if there is no restriction to the phase of injected irregular currents, the currents at the same frequency may cancel each other out, and then their convergent current may be too small to cause a detectable response, for which reason islanding detection will be severely affected. Accordingly, this paper raises a compatibility issue, which requires the phase difference between any two injected irregular currents to be within a certain interval. In response to this issue, a solution is proposed. According to this solution, the terminal voltage of DG units is referenced to conduct irregular currents injection, and only certain high-frequency currents are used as injected currents. If this solution is adopted by as many manufacturers as possible, the effect and reliability of such methods will be greatly improved. [ABSTRACT FROM AUTHOR]

In order to study the coupling relationship between large earthquakes and the ionosphere, the techniques of ionosphere data acquisition were refined by the Crustal Movement Observation Network of China (CMONOC) to detect the pre-earthquake ionospheric abnormal and coseismic ionospheric disturbances (CID) of the Mw 6.6 Lushan earthquake on 20 April 2013. Based on the regional ionosphere maps (RIMs) derived from the Global Positioning System (GPS) observations of CMONOC, the ionospheric local effects near the epicenter of the Lushan earthquake one month prior to the shock were analyzed. The results show that the total electron content (TEC) anomalies appeared 12–14 (6–8 April), 19 (1 April), and 25–27 (24–26 March) days prior to the Lushan earthquake, which are defined as periods 1, 2, and 3, respectively. Multi-indices including the ring current index (Dst), geomagnetic planetary (Kp) index, wind plasma speed (Vsw) index, F10.7, and solar flares were utilized to represent the solar–terrestrial environment in different scales and eliminate the effects of solar and geomagnetic activities on the ionosphere. After the interference of solar–terrestrial activity and the diurnal variation in the lower thermosphere were excluded, the TEC variations with obvious equatorial ionospheric anomaly (EIA) in period-1 were considered to be related to the Lushan earthquake. We further retrieved precise slant TECs (STECs) near the epicenter to study the coseismic ionospheric disturbance (CID). The results show that there was clear STEC disturbance occurring within half an hour after the Lushan earthquake, and the CID propagation distance was less than the impact radius of the Lushan earthquake (689 km). The shell models with different altitudes were adopted to analyze the propagation speed of the CID. It is found that at the F2-layer with the altitude of 277 km, which had a CID horizontal propagation velocity of 0.84 ± 0.03 km/s, was in accordance with the acoustic wave propagation velocity. The calculated velocity acoustic wave from the epicenter to the ionospheric pierce points of this shell model was about 0.53 ± 0.03 km/s, which was also consistent with its actual velocity within the altitude of 0–277 km. Affected by the geomagnetic field, the CID mainly propagated along the southeast direction at the azimuth of 190°, which was almost parallel to the local magnetic line. [ABSTRACT FROM AUTHOR]

One class of islanding detection methods, known as impedance measurement-based methods and voltage change monitoring-based methods, are implemented through injecting irregular currents into the network, for which reason they are defined in this paper as irregular current injection methods. This paper indicates that such methods may be affected by distributed generation (DG) unit cut-in events. Although the network impedance change can still be used as a judgment basis for islanding detection, the general impedance measurement scheme cannot separate island events from DG unit cut-in events in multi-DG operation. In view of this, this paper proposes a new islanding detection method based on an improved impedance measurement scheme, i.e., dynamic impedance measurement, which will not be affected by DG unit cut-in events and can further assist some other equipment in islanding detection. The simulations and experiments verify the stated advantages of the new islanding detection method. [ABSTRACT FROM AUTHOR]

To explore the effect mechanism of polyoxymethylene dimethyl ethers (PODE)-diesel blends on nitric oxide (NO) and soot emission characteristics, the in-cylinder pressure and the emissions of blends with PODE volume fraction at 10%, 20%, and 30% (labeled P10, P20, and P30) are tested, also the in-cylinder working process of a diesel engine at 2600 r/min under 100% load is simulated by using a computational fluid dynamics software. The results show that both the in-cylinder temperature and the concentration of oxygen atoms have an important effect on the emissions of PODE-diesel blend fuels. PODE helps to increase the average combustion temperature and oxygen atom distribution range in the cylinder, thus reducing the range of lean combustion zone with uneven mixture. With the addition of PODE, the ignition delay period of PODE-diesel blend fuel is shortened, speeding up the combustion process. When the blending ratio of PODE is increased, an ascent of NO production and NO concentration distribution is observed, while soot emissions are significantly reduced, and the ultimate soot generation of P30 fuel under the calibrated working condition is decreased by nearly 80% compared with diesel. [ABSTRACT FROM AUTHOR]