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In the end of 2019, the epidemic of a new coronavirus (SARS-CoV-2) occurred in Wuhan and spread rapidly. Changsha, a city located south to the epicenter, was soon impacted. To control the transmission of the coronavirus and avoid nosocomial infection, triage procedures based on epidemiology were implemented in a local hospital of the city. This retrospective study analyzed the data collected during the triage period and found that COVID-19 patients were enriched seven folds into the Section A designated for rapid detection and quarantine. On the other side, roughly triple amounts of visits were received at the Section B for patients without obvious epidemiological history. Eight COVID-19 cases were spotted out of 247 suspected patients. More than 50% of the suspected patients were submitted to multiple rounds of nucleic acid analysis for SARS-CoV-2 infection. Of the 239 patients who were diagnosed as negative of the virus infection,188 were successfully revisited and none was reported as a COVID-19 case. Of the eight COVID-19 patients, three were confirmed only after multiple rounds of nucleic acid analysis. Besides comorbidities, delayed sharing of epidemiological history added another layer of complexity to the diagnosis in practice. While SARS-CoV-2 epidemic is being alerted in many countries, our report will be helpful to other colleagues in rapid identification of COVID-19 cases and controlling the transmission of the disease.

Monitoring and delineating the spatial distribution of shale fracturing is fundamentally important to shale gas production. Standard monitoring methods, such as time-lapse seismic, cross-well seismic and micro-seismic methods, are expensive, timeconsuming, and do not show the changes in the formation with time. The resistivities of hydraulic fracturing fluid and reservoir rocks were measured. The results suggest that the injection fluid and consequently the injected reservoir are characterized by very low resistivity and high chargeability. This allows using of the controlled-source electromagnetic method (CSEM) to monitor shale gas hydraulic fracturing. Based on the geoelectrical model which was proposed according to the well-log and seismic data in the test area the change rule of the reacted electrical field was studied to account for the change of shale resistivity, and then the normalized residual resistivity method for time lapse processing was given. The time-domain electromagnetic method (TDEM) was used to continuously monitor the shale gas fracturing at the Fulin shale gas field in southern China. A high-power transmitter and multi-channel transient electromagnetic receiver array were adopted. 9 h time series of Ex component of 224 sites which were laid out on the surface and over three fracturing stages of a horizontal well at 2800 m depth was recorded. After data processing and calculation of the normalized resistivity residuals, the changes in the Ex signal were determined and a dynamic 3D image of the change in resistivity was constructed. This allows modeling the spatial distribution of the fracturing fluid. The model results suggest that TDEM is promising for monitoring hydraulic fracturing of shale.

The paper introduces energy storage systems (ESSs) and carbon emission trade (CET), gradually constructs joint scheduling optimization model for wind power and thermal power considering ESSs and CET. Firstly, the paper takes the maximum system benefit as the objective function considering load supply and demand balance constraint, unit operation constraint and system reserve constraints, establishes the basic scheduling mathematical model for wind power and thermal power. Secondly, the paper respectively builds carbon emission cost model of thermal power generation considering CET, ESSs’ operation profit model and puts forward system scheduling comprehensive objective function considering CET and ESSs. Thirdly, the paper constructs jointly scheduling model for wind power and thermal power considering ESSs’ operation constraints, CET’s constraint and newly system reserve constraint. Finally, 10 thermal power units and 2800MW wind power turbine are taken as simulation system. The result shows: the large-scale grid connection of wind power needs rely on thermal power units to provide reserve, which could result in the reduction of unit utilization efficiency and correspondingly increase coal consumption of units’ power generation, but system overall coal consumption rate will reduce. CET can transform wind power cleaning characteristics into economic benefits, promote system to consume wind power and reduce abandoned wind power. ESSs can gentle the electric load curve and improve the grid-connected space by adjusting its charge and discharge characteristics, but system overall benefit reduces subjected to high ESSs’ fixed costs. System overall benefit will reaches maximum when ESSs and CET are simultaneously introduced, which indicates that they have synergistic optimization effect.

Anoctamin-1 (ANO1) (TMEM16A) is a calcium-activated chloride channel that plays critical roles in diverse physiological processes, such as sensory transduction and epithelial secretion. ANO1 levels have been shown to be altered under physiological and pathological conditions, although the molecular mechanisms that control ANO1 protein levels remain unclear. The ubiquitin–proteasome system is known to regulate the levels of numerous ion channels, but little information is available regarding whether and how ubiquitination regulates levels of ANO1. Here, we showed that two E3 ligases, TRIM23 and TRIM21, physically interact with the C terminus of ANO1. In vitro and in vivo assays demonstrated that whereas TRIM23 ubiquitinated ANO1 leading to its stabilization, TRIM21 ubiquitinated ANO1 and induced its degradation. Notably, ANO1 regulation by TRIM23 and TRIM21 is involved in chemical-induced pain sensation, salivary secretion, and heart-rate control in mice, and TRIM23 also mediates ANO1 upregulation induced by epidermal growth factor treatment. Our results suggest that these two antagonistic E3 ligases act together to control ANO1 expression and function. Our findings reveal a previously unrecognized mechanism for regulating ANO1 protein levels and identify a potential molecular link between ANO1 regulation, epidermal growth factor, and other signaling pathways.

A2BAR (A2B adenosine receptor) has been implicated in several physiological conditions, such as allergic or inflammatory disorders, vasodilation, cell growth and epithelial electrolyte secretion. For mediating the protein–protein interactions of A2BAR, the receptor's C-terminus is recognized to be crucial. In the present study, we unexpectedly found that two point mutations in the A2BAR C-terminus (F297A and R298A) drastically impaired the expression of A2BAR protein by accelerating its degradation. Thus we tested the hypothesis that these two point mutations disrupt A2BAR's interaction with a protein essential for A2BAR stability. Our results show that both mutations disrupted the interaction of A2BAR with actinin-1, an actin-associated protein. Furthermore, actinin-1 binding stabilized the global and cell-surface expression of A2BAR. By contrast, actinin-4, another non-muscle actinin isoform, did not bind to A2BAR. Thus our findings reveal a previously unidentified regulatory mechanism of A2BAR abundance.

Mutations of cystic fibrosis transmembrane conductance regulator (CFTR), an epithelial ligand-gated anion channel, are associated with the lethal genetic disease cystic fibrosis. The CFTR G551D mutation impairs ATP hydrolysis and thereby makes CFTR refractory to cAMP stimulation. Both wild-type (WT) and G551D CFTR have been implicated in regulatory volume decrease (RVD), but the underlying mechanism remains incompletely understood. Here, we show that the channel activity of both WT and G551D CFTR is directly stimulated by mechanical perturbation induced by cell swelling at the single-channel, cellular, and tissue levels. Hypotonicity activated CFTR single channels in cell-attached membrane patches and WT-CFTR-mediated short-circuit current (Isc) in Calu-3 cells, and this was independent of Ca2+ and cAMP/PKA signaling. Genetic suppression and ablation but not G551D mutation of CFTR suppressed the hypotonicity- and stretch-induced Isc in Calu-3 cells and mouse duodena. Moreover, ablation but not G551D mutation of the CFTR gene inhibited the RVD of crypts isolated from mouse intestine; more importantly, CFTR-specific blockers markedly suppressed RVD in both WT- and G551D CFTR mice, demonstrating for the first time that the channel activity of both WT and G551D CFTR is required for epithelial RVD. Our findings uncover a previously unrecognized mechanism underlying CFTR involvement in epithelial RVD and suggest that the mechanosensitivity of G551D CFTR might underlie the mild phenotypes resulting from this mutation.—Xie, C., Cao, X., Chen, X, Wang, D., Zhang, W. K., Sun, Y., Hu, W., Zhou, Z., Wang, Y., Huang, P. Mechanosensitivity of wild-type and G551D cystic fibrosis transmembrane conductance regulator (CFTR) controls regulatory volume decrease in simple epithelia.

Adenylyl cyclases (ACs) generate cAMP, a second messenger of utmost importance that regulates a vast array of biological processes in all kingdoms of life. However, almost nothing is known about how AC activity is regulated through protein degradation mediated by ubiquitination or other mechanisms. Here, we show that transcriptional regulator interacting with the PHD-bromodomain 1 (TRIP-Br1, Sertad1), a newly identified protein with poorly characterized functions, acts as an adaptor that bridges the interaction of multiple AC isoforms with X-linked inhibitor of apoptosis protein (XIAP), a RING-domain E3 ubiquitin ligase. XIAP ubiquitinates a highly conserved Lys residue in AC isoforms and thereby accelerates the endocytosis and degradation of multiple AC isoforms in human cell lines and mice. XIAP/TRIP-Br1-mediated degradation of ACs forms part of a negative-feedback loop that controls the homeostasis of cAMP signaling in mice. Our findings reveal a previously unrecognized mechanism for degrading multiple AC isoforms and modulating the homeostasis of cAMP signaling. DOI: http://dx.doi.org/10.7554/eLife.28021.001

CFTR function is tightly regulated by many interacting proteins.Intermediate filament protein keratin 18 increases the cell surface expression of CFTR by interacting with the C-terminal hydrophobic patch of CFTR.K18 controls the function of CFTR.These findings offer novel insights into the regulation of CFTR and suggest that K18 and its dimerization partner, K8, may be modifier genes in cystic fibrosis. Malfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) leads to cystic fibrosis, but the regulation of CFTR is not fully understood. Here, we identified the intermediate filament protein keratin K18 (K18) as a CFTR-binding protein by various approaches. We mapped a highly conserved "hydrophobic patch" ((1413)FLVI(1416)) in the CFTR C-terminus, known to determine plasmalemmal CFTR stability, as the K18-binding site. On the other hand, the C-terminal tail of K18 was found to be a critical determinant for binding CFTR. Overexpression of K18 in cells robustly increased the surface expression of wild-type CFTR, whereas depletion of K18 through RNA interference specifically diminished it. K18 binding increased the surface expression of CFTR by accelerating its apical recycling rate without altering CFTR biosynthesis, maturation, or internalization. Importantly, CFTR surface expression was markedly reduced in duodenal and gallbladder epithelia of K18(-/-) mice. Taken together, our results suggest that K18 increases the cell surface expression of CFTR by interacting with the CFTR C-terminal hydrophobic patch. These findings offer novel insights into the regulation of CFTR and suggest that K18 and its dimerization partner, K8, may be modifier genes in cystic fibrosis.

The forward modeling procedure used in this article is formulated with the volume integral equation based on the tensor Green’s function. The electromagnetic components responses are first calculated in the frequency domain and then transformed to the time domain by digital filtering. The valley and hill topography with a layered earth is stimulated by a horizontal electric dipole (HED) transmitter, which is common in field surveys, and the TEM responses are calculated at the transmitter and receivers. The topography effects on the long offset electromagnetic transient (LOTEM) responses are discussed in detail. The results show that both valley and hill topography has significant effect on the LOTEM measurement. If the HED is located in the bottom of a valley, the distortion of the observed anomalous field at distance is severe. A valley at the receiver locations show a strong effect but are localized in space and time. In general, hill-shaped topography shows smaller effects no matter where its located. When the topography is located between source and receivers, the influence is negligible. We conclude that the location of the source is much more important than the receivers and it is critical to put the transmitter in an open flat area in the field survey.

Total Organic Content (TOC) is one of the key and important parameters to effectively evaluate the shale gas formation production potential. According to geological deposition theory, the TOC is the basic key element that controls the form of pyrite in the marine sediment under deep water strong reducing deposition environment. There is a close relationship between the TOC and pyrite in such deep water reducing deposition environment. Through the laboratory measurement and analysis of the complex resistivity on marine shale formation core samples from South China, the high TOC shale reservoir core samples contain more pyrite, and they show clearly low resistivity and high polarization anomaly. In comparison with well log data, the laboratory measurements of TOC and pyrite are closely related to the results from the log data analysis. We concluded that high TOC marine shale formation has the characterization of low resistivity and high induced polarization (IP) anomaly. Based on the research results, the application of the induced polarization or complex resistivity method to measure the subsurface resistivity and polarization anomaly is a new approach to effectively evaluate the TOC content within the shale gas formation, and it has high potential value for future shale gas reservoir evaluation and characterization.

The synchronized array magnetotelluric method (SAMT) has produced good results in field trials in very rugged mountain regions in southern China where conventional seismic techniques have not provided satisfactory data.

Summary The nuclear factor kappa B (NFκB) pathway controls a variety of processes, including inflammation, and thus, the regulation of NFκB has been a continued focus of study. Here, we report a newly identified regulation of this pathway, involving direct binding of the transcription factor NFκB1 (the p105 subunit of NFκB) to the C-terminus of the A 2B adenosine receptor (A 2B AR), independent of ligand activation. Intriguingly, binding of A 2B AR to specific sites on p105 prevents polyubiquitylation and degradation of p105 protein. Ectopic expression of the A 2B AR increases p105 levels and inhibits NFκB activation, whereas p105 protein levels are reduced in cells from A 2B AR-knockout mice. In accordance with the known regulation of expression of anti- and pro-inflammatory cytokines by p105, A 2B AR-null mice generate less interleukin (IL)-10, and more IL-12 and tumor necrosis factor (TNF-α). Taken together, our results show that the A 2B AR inhibits NFκB activation by physically interacting with p105, thereby blocking its polyubiquitylation and degradation. Our findings unveil a surprising function for the A 2B AR, and provide a novel mechanistic insight into the control of the NFκB pathway and inflammation.

The CSAMT responses of geoelectric media are actually the accumulation of electromagnetic response and induced polarization under the stimulation of controlled source. The resistivity is dealt as a parameter which is scarcely related to the frequency when we proceed the forward and inversion with field data. Due to the induced polarization of underground layers, however, the resistivity of polarized layers is complex number relating to the frequencies and using only resistivity will lead an inaccurate result. This paper provides a primary trial in solving this problem that not only the current research situation of basic theory of IP in recent years, but also a few of preliminary modeling results are presented

A 2-D Audio Frequency Magnetotelluric (AMT) and Magnetotelluric (MT) survey were successfully completed in area of Sao Francisco, Brazil last year. Totally 40 MT sites were designed to cover part of one seismic line in order to compare the data of two geophysical methods. The main objective of this project is to supply the resistivity profile and data comparison with seismic exploration to outline the depth of basement ranging from the surface to 4,000 meters. The optimal inversion method and interpretation strategy for this 2-D AMT/MT data was first selected through the comparison of different modeling and inversion tryout results using a variety of inversion methods and actual field 2-D AMT/MT data. Upon applying the optimal inversion method and interpretation strategy, the depth and distribution of the basement was estimated based on the 2-D AMT/MT inversion results. From the 2D inversion of different modes, one can see that the depth of basement of this area is roughly from surface to about 1.2 km depth and it was relatively flat with a little fluctuation, which is correlate well with the result of seismic data. The interpretation result of the 2-D AMT/MT surveys indicates that AMT/MT methods were proven to be the effective methods for prospecting deep structures which in many cases appear to correlate well with geological structures.

The produced water of oilfield is one of the primary contaminative sources of oilfield ecosystem, which includes large quantity of dirty mire mixed with the oil, sulfide, etc. Meanwhile, its direct rowing would result in serious pollution. Purifying this kind of produced water has been emphasized by more and more oil-fields. This paper presented the control algorithm of PH which is based on the PH control of the output of reactor. The control diagram of controlled object and the relevant controller are proposed in this article according to the produced water treatment process. This paper is to resolve the actual problem and aim of studying the control method of the system with time-delayed, and discuss the application of the Smith estimate control method and fuzzy control method in pharmacy dosing system.

Series of models are designed to test the influences of some parameters such as resistivity of overburden layer, basement and transmitter-receiver layouts, to a given 3D conductive anomaly in the layered earth model by transient electromagnetic (TEM) method, which is often used in engineering exploration. The forward modeling procedure used is formulated with volume integral equation based on tensor Green's function. The response of electromagnetic components are first calculated in frequency domain and then transformed to time domain by digital filtering. Through a series of modeling, it shows that the transient response of both e x and V z components are larger if the overburden layer and basement are resistive. The models also illustrate that S-s layouts are not sensitive to the variation of basement resistivity and it is more suitable for surveying shallow target.

Summary Theoretical and numerical modeling results show the feasibility of residual oil mapping and d ynamic monitoring of steam or water driven reservoirs by using the electric source TEM method. A pilot survey of customized array TEM was carried out over a steam driven heavy oil reservoir. Field results confirm that the resistivity anomalies are well correlated with residual oil saturation.

Analytical and numerical solutions of time domain electromagnetic responses of earth model with axis symmetry have been derived and model responses have been calculated with a pulse source stimulating inside metal casing. Anomalous pattern of TEM responses varying with casing parameters (thickness, conductivity and magnetic permeability) and sensitivity to resistivity changes of formation outside of casing were analyzed. Model results have shown that through casing TEM sounding is feasible and has advantages of multi-components, multi-parameters, deep and untouched probing.

A three dimensional body is designed to simulate the valley shaped topography. Transient responses are calculated for topography at source location and at receiver location respectively. Modeling results are shown by relative anomalies in contours. The behavior of the topographic effect to transient eletromagnetic field responses can be characterized by local anomaly for topography at receiver location, and by equivalently an extra source with strong high frequency excitation for topography at source location. Learning from the modeling results, it is emphasized that the ground wire source shall be set up at place as uniform as possible for reliable deep sounding measurements.