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Abstract The emergence of various topological semimetal states presents a novel opportunity for enhancing the efficiency of thermoelectric transport. This study introduces a recipe to improve the thermoelectric (TE) performance in topological materials containing single‐pair Weyl points (SP WPs) fermions and phonons. The recipe focuses on two key factors contributing to the enhancement of TE performance: the increase in the density of states to achieve a high power factor, and the introduction of additional phonon scattering to reduce the lattice thermal conductivity. The proposed recipe is confirmed in a half‐metallic SP WPs material BaNiIO6 through first‐principles methods. An enhanced density of states arises near the energy of the SP WPs in BaNiIO6, leading to a peak power factor connected to the complex Fermi surface due to the degeneracy of Weyl pockets in energy. Furthermore, it is shown that the SP WPs phonons in BaNiIO6 possess a high scattering rate and can likely contribute to the low lattice thermal conductivity, especially when two crossing points in SP WPs do not degenerate in frequency. The new recipe can be used for discovering high‐performance thermoelectric materials in the future by utilizing the transport advantages of degenerate‐in‐energy SP WPs fermions and non‐degenerate‐in‐frequency SP WPs phonons.

Stachys yingzuijieensis, a new species from western Hunan, China, is described and illustrated. Molecular phylogenetic analyses based on three nuclear ribosomal DNA loci (ETS, ITS and 5S-NTS) recovered S. yingzuijieensis within the Stachys clade and as a sister group of S. arrecta. The two species can be easily distinguished by the morphology of lamina, corolla and nutlet. A key to all species of Stachydeae from China is also provided.

Objective To detect the serum level of microRNA (miR)-155-5p in IgA nephropathy patients and examine its clinical significance. Methods The patients with IgA nephropathy followed up for 3 years were selected. Serum level of miR-155-5p was detected by real-time fluorescent quantitative polymerase chain reaction (PCR). Based upon declining rate of renal function (RF), they were assigned into two groups of RF progression (A, n=42) and relatively stable RF (B, n=63). Inter-group differences in clinical and laboratory parameters were compared. Logistic regression analysis was performed for identifying the risk factors for RF progression. Pearson’s or Spearman’s correlation analysis was performed for assessing the correlation between serum level of miR-155-5p and baseline estimated glomerular filtration rate (eGFR), urinary protein quantification, declining rate of RF and renal pathological data. Receiver operating characteristic (ROC) curve was plotted for evaluating the capability of miR-155-5p level for judging the progress of RF. Results As compared with group B, group A had a higher prevalence of hypertension (88.09% vs 19.05%), greater baseline urinary protein quantification [(3.11±2.16)g/24 h vs (1.07±0.87)g/24 h], higher baseline blood creatinine [(106.74±51.27)μmol/L vs (86.90±36.90)μmol/L] and higher total kidney pathology T score (61 vs 13, P

We proposed a new mathematical model to study the COVID-19 infection in piecewise fractional differential equations. The model was initially designed using the classical differential equations and later we extend it to the fractional case. We consider the infected cases generated at health care and formulate the model first in integer order. We extend the model into Caputo fractional differential equation and study its background mathematical results. We show that the fractional model is locally asymptotically stable when R0

Abstract When a spherical droplet moves parallel to the direction of motion of its surrounding gas medium, it will deform into an ellipsoidal droplet. In this paper, an exposition of a novel model for predicting the minimum flow rate for the continuous removal of liquids from gas wells based on two theories is presented. First, droplet breakup principle is utilized to microscopically obtain the maximum size parameters of ellipsoidal droplets, and second, droplet force equilibrium is adopted to macroscopically calculate the critical droplet entrainment rate. Moreover, effect of variations in the windward area (attributed to droplet deformation) on the drag coefficient is determined. Impacts of variations in pressure, temperature, and pipe diameter on the gas‐liquid two‐phase friction resistance and gas‐liquid surface tension are also considered. For model verification and comparison with other droplet entrainment models, field data from 3436 gas wells are utilized. The field data well validates the results with a 92% accuracy, indicating that the new model has a better comprehensive performance in determining whether or not a gas well is loaded. Besides, parameter sensitivity analyses including the effects of drag coefficient, surface tension, and friction coefficient on the minimum flow rate of gas are performed. Finally, the relationship curve of critical droplet entrainment rates corresponding to different pressures and pipe diameters is established.

The purpose of this study is to establish an elastic–plastic damage constitutive model of shale and simulate the elastic–plastic damage characteristics of shale under stress. Based on the unified strength theory and the mechanics of shale rock samples characterized in laboratory tests, a new elastic–plastic damage constitutive model for shale is established by introducing compression factors and damage variables. The main considerations include the compressibility of primary fractures and pores in the shale core, and the formation of secondary cracks in the rock matrix under stress. A fully implicit backward Euler regression mapping algorithm has been used to solve the model, and the numerical simulation results are in good agreement with the experimental results. The results show that the model established in this paper can accurately simulate the elastic–plastic damage characteristics of shale under stress, and that it provides a new numerical simulation method for describing the elastic–plastic damage in shale.

We consider a new mathematical model for the COVID-19 disease with Omicron variant mutation. We formulate in details the modeling of the problem with omicron variant in classical differential equations. We use the definition of the Atangana–Baleanu derivative and obtain the extended fractional version of the omicron model. We study mathematical results for the fractional model and show the local asymptotical stability of the model for infection-free case if R0

As the most common form of dementia and a progressive neurodegenerative disorder, Alzheimer’s disease (AD) affects over 10% world population with age 65 and older. The disease is neuropathologically associated with progressive loss of neurons and synapses in specific brain regions, deposition of amyloid plaques and neurofibrillary tangles, neuroinflammation, blood–brain barrier (BBB) breakdown, mitochondrial dysfunction, and oxidative stress. Despite the intensive effort, there is still no cure for the disorder. Stem cell-derived exosomes hold great promise in treating various diseases, including AD, as they contain a variety of anti-apoptotic, anti-inflammatory, and antioxidant components. Moreover, stem cell-derived exosomes also promote neurogenesis and angiogenesis and can repair damaged BBB. In this review, we will first outline the major neuropathological features associated with AD; subsequently, a discussion of stem cells, stem cell-secreted exosomes, and the major exosome isolation methods will follow. We will then summarize the recent data involving the use of mesenchymal stem cell- or neural stem cell-derived exosomes in treating AD. Finally, we will briefly discuss the challenges, perspectives, and clinical trials using stem cell-derived exosomes for AD therapy.

Super-spreaders of the novel coronavirus disease (or COVID-19) are those with greater potential for disease transmission to infect other people. Understanding and isolating the super-spreaders are important for controlling the COVID-19 incidence as well as future infectious disease outbreaks. Many scientific evidences can be found in the literature on reporting and impact of super-spreaders and super-spreading events on the COVID-19 dynamics. This paper deals with the formulation and simulation of a new epidemic model addressing the dynamics of COVID-19 with the presence of super-spreader individuals. In the first step, we formulate the model using classical integer order nonlinear differential system composed of six equations. The individuals responsible for the disease transmission are further categorized into three sub-classes, i.e., the symptomatic, super-spreader and asymptomatic. The model is parameterized using the actual infected cases reported in the kingdom of Saudi Arabia in order to enhance the biological suitability of the study. Moreover, to analyze the impact of memory index, we extend the model to fractional case using the well-known Caputo–Fabrizio derivative. By making use of the Picard-Lindelöf theorem and fixed point approach, we establish the existence and uniqueness criteria for the fractional-order model. Furthermore, we applied the novel fractal-fractional operator in Caputo–Fabrizio sense to obtain a more generalized model. Finally, to simulate the models in both fractional and fractal-fractional cases, efficient iterative schemes are utilized in order to present the impact of the fractional and fractal orders coupled with the key parameters (including transmission rate due to super-spreaders) on the pandemic peaks.

Abstract Performing stress‐sensitivity evaluation on a high‐temperature and high‐pressure gas reservoir is essential for correctly understanding the characteristics of physical property changes and reasonably designing the development scheme of a reservoir under stratum conditions. By focusing on six core samples with different physical properties in a gas field in the Yingqiong Basin, stress‐sensitivity experiments have been conducted along with mercury intrusion porosimetry and X‐ray diffraction measurements to study the relationship among porosity, permeability, and effective stress at a temperature of 140°C and effective stress ranging from 2 MPa to 70 MPa. Our results showed that the stress‐sensitivity curve characterized by three‐stage segmentation is primarily affected by average pore radius and mineral composition but has no direct relation with porosity and permeability. Meanwhile, the stress sensitivity of permeability is mainly related to the average pore throat radius and mineral composition of core specimen. The smaller the pore throat radius and the higher the clay content, the stronger the stress sensitivity of permeability. Under high‐temperature and high‐pressure conditions, the stress sensitivities of permeability and porosity can be characterized by power functions although the stress sensitivity of permeability is about 2–11 times higher than that of porosity.

We formulate a new mathematical model for better understanding of the dynamics of Hepatitis B virus (HBV) with asymptomatic carriers and vaccination classes. Initially, we first formulate the problem in integer order derivative and then apply the fractional operator to extend the model due to advantages of the he fractional derivative. We carefully examine the local and global asymptotical analysis of the model in integer order. We found when R0

The coronavirus still an epidemic in most countries of the world and put the people in danger with so many infected cases and death. Considering the third wave of corona virus infection and to determine the peak of the infection curve, we suggest a new mathematical model with reported cases from March 06, 2021, till April 30, 2021. The model provides an accurate fitting to the suggested data, and the basic reproduction number calculated to be R0=1.2044. We study the stability of the model and show that the model is locally as well as globally asymptotically stable when R0

The newly arose irresistible sickness known as the Covid illness (COVID-19), is a highly infectious viral disease. This disease caused millions of tainted cases internationally and still represent a disturbing circumstance for the human lives. As of late, numerous mathematical compartmental models have been considered to even more likely comprehend the Covid illness. The greater part of these models depends on integer-order derivatives which cannot catch the fading memory and crossover behavior found in many biological phenomena. Along these lines, the Covid illness in this paper is studied by investigating the elements of COVID-19 contamination utilizing the non-integer Atangana–Baleanu–Caputo derivative. Using the fixed-point approach, the existence and uniqueness of the integral of the fractional model for COVID is further deliberated. Along with Ulam–Hyers stability analysis, for the given model, all basic properties are studied. Furthermore, numerical simulations are performed using Newton polynomial and Adams Bashforth approaches for determining the impact of parameters change on the dynamical behavior of the systems.

Abstract. Background:. Management of tumors has become more complex owing to tumor heterogeneity. Fewer studies have been performed on intra-tumor heterogeneity of endometrial cancer (EC) until now. Therefore, it is of great clinical value to explore the intra-tumor heterogeneity of EC based on clinical features and gene expression profiles. Methods:. A total of 1688 patients with EC were screened and 114 patients were finally selected, including specimens from 84 patients with primary EC without relapse (PE) and the paired metastases (P-M) specimens, as well as specimens from 30 patients with primary EC with relapse (RPE) and the paired relapsed EC (P-RE) specimens. Microarray and RNA-seq were used to detect gene expression of EC samples. Clinicopathological characteristics and molecular data were compared between PE and P-M groups and between RPE and P-RE groups to explore the intra-tumor heterogeneity of EC. Results:. The clinical intra-tumor spatial heterogeneity of pathological type, grade, ER status, and PR status between PE and P-M were 17.9%, 13.1%, 28.6%, and 28.6%, respectively. The clinical intra-tumor spatiotemporal heterogeneity of pathological type, grade, ER status, and PR status between RPE and P-RE were 16.7%, 33.3%, 25.0%, and 37.5%, respectively. Cluster analysis sorts EC samples based on progression type of lesion and their pathological type. There were differentially expressed genes between PE and P-M and between RPE and P-RE, of which gene ontology and Kyoto Encyclopedia of Genes and Genomes analysis were mainly enriched in cell proliferation, the p53 signaling pathway, etc. Conclusions:. Clinical and molecular data showed that there was spatiotemporal heterogeneity in intra-tumor of EC, which may add to the complexity of diagnosis and therapeutics for EC. Considering the intra-tumor heterogeneity, sequential chemotherapy and precision medicine may be a more suitable treatment plan for EC.

Abstract. Background:. Fusion genes may play an important role in tumorigenesis, prognosis, and drug resistance; however, studies on fusion genes in endometrial cancer (EC) are rare. This study aimed to identify new fusion genes and to explore their clinical significance in EC. Methods:. A total of 28 patients diagnosed with EC were enrolled in this study. RNA sequencing was used to obtain entire genomes and transcriptomes. STAR-comparison and STAR-fusion prediction were applied to predict the fusion genes. Chi-square tests and Student t tests were used to verify the clinical significance with SPSS 13.0 software. Results:. New fusion genes were found, and the number of fusion genes varied from 3 to 110 among all patients with EC. The type of fusion genes varied and included messenger RNA (mRNA)-mRNA, long non-coding RNA (lncRNA)-lncRNA, and lncRNA-mRNA. There were six fusion genes with high fusion rates, namely, RP11–123O10.4–GRIP1, RP11–444D3.1–SOX5, RP11–680G10.1–GSE1, NRIP1–AF127936.7, RP11–96H19.1–RP11–446N19.1, and DPH7–PTP4A3. Further studies showed that these fusion genes are related to stage, grade, and recurrence, in which NRIP1–AF127936.7 and DPH7–PTP4A3 were found only in stage III patients with EC. DPH7–PTP4A3 was found in grades 2 and 3, and recurrent patients with EC. Conclusion:. Fusion genes play an essential role in EC. Six genes that are overexpressed with high fusion rates are identified. NRIP1–AF127936.7 and DPH7–PTP4A3 might be related to stage, and DPH7–PTP4A3 be related to grade and recurrence.

Abstract The assumption of constant reservoir permeability is not strictly applicable to reservoirs where rock properties undergo changes, such as stress-sensitive porous media. Most researches on the permeability stress sensitivity mainly concentrated on experimental approach, physical modeling or pressure transient analysis, whereas rate transient analysis does not attract much attention. Based on source/sink function method, this paper develops a seepage model of multi-fractured horizontal well incorporating stress-sensitive permeability. The model is semi-analytically solved by fracture discretization, Pedrosa’s transformation, perturbation theory, and integration transformation method. Not only pressure transient analysis, but also rate transient analysis is separately performed with relevant parameters. The model presented here can provide some insights into well dynamic forecasting during exploiting such reservoirs, and contribute to establish the theoretical basic for transient analysis efficiently.

Inclined wells has recently been adopted to develop fractured-vuggy carbonate hydrocarbon reservoirs (FVCHRs) composed by matrix, fracture and vug system. Therefore, it is significant for us to describe pressure transient of inclined well for FVCHRs. In this paper, it is assumed that vug and fracture system connect with wellbore, and inter-porosity flow from vug to fracture system appears. Therefore, the pressure transient responses model of inclined well with triple-porosity dual-permeability behavior was built. The model is solved by employing Laplace integral transform and finite cosine Fourier transform. Real-domain solution of the model is obtained by Stehfest inversion algorithm. On the basis model of the published paper, the solution of the simplified model of this paper was validated with horizontal and vertical well of FVCHRs with triple-porosity dual-permeability behavior, and results reach a good agreement. Type curve, according to pressure derivative curve characteristic, can be divided into eight flow regimes, which includes wellbore storage, skin reflect, early vertical radial flow, top and bottom boundary reflection, linear flow, inter-porosity flow from vug to fracture, inter-porosity from matrix to vug and fracture and pseudo-radial flow regimes. The influence of some vital parameters (inclination angle, inter-porosity flow coefficient, well length and permeability ratio etc.) on dimensionless pressure and its derivative curves are discussed in detail. The presented model can be used to understand pressure transient response characteristic of inclined wells in FVCHRs with dual-permeability behavior.

Introduction: Radiotherapy, combined regimens as platinum-paclitaxel chemotherapy and/or endocrine therapy is an important adjuvant treatment after surgery for endometrial cancer (EC). While, the resistance to them remain unclear. In our study, to separate the characteristics of side population (SP) cells from EC cell lines, study the mechanism of Taxol-resistance, progestin resistance and radioresistanc, and provide the basic for EC.Methods: SP cells from EC cell lines HEC-1A, Ishikawa and RL95-2 were separated by Hoechst 33342 staining and flow cytometry analysis. The expression of breast cancer resistance protein (BCRP) in SP cells and non-SP cells from HEC-1A was examined by immunocytochemistry, and the radiation-resistant and Taxol-resistant characteristics of SP cells and non-SP cells were compared by MTS. Ishikawa, Ishikawa-SP, and Ishikawa-non-SP cells incubated with MPA were selected for cell apoptosis assays by using flow cytometry. The expression of caspase-3 was examined by immunocytochemistry, and autophagy was detected by MDC staining.Results: Small proportions of SP cells, namely, 1.44 ± 0.93%, 2.86 ± 3.09%, and 2.87 ± 1.29%, were detected in HEC-1A, Ishikawa and RL95-2, respectively. There was a stronger clone formation efficiency for the SP cells than for non-SP cells in HEC-1A [(6.02 ± 1.17) vs. (0.53±0.20)%, P = 0.001], and there was a significant difference in the rate of tumourigenicity between the SP cells and non-SP cells in HEC-1A (87.5 vs. 12.5%). There were higher levels of BCRP expression (P = 0.001) and resistance to Taxol and radiation (P < 0.05) in the SP cells than in non-SP cells. After MPA treatment, the apoptosis rates were significantly different among the Ishikawa, Ishikawa-SP and Ishikawa-non-SP groups [(4.64 ± 0.18)%, (4.01 ± 0.43)%, and (9.3 ± 0.67)%; (P = 0.05)], and the expression of Caspase-3 in the Ishikawa group was higher than that in Ishikawa-SP group. The autophagic activity of the Ishikawa-SP cells was the strongest, while the autophagic activity of Ishikawa-non-SP was the weakest.Conclusions: There is a significant enrichment in SP cells among different EC cell lines, and these SP cells be more resistant to Taxol, MPA and radiation therapy. The overexpression of BCRP among SP cells may be the cause of resistance to Taxol, progestin and radiotherapy, which may be related to apoptosis and autophagic activity.

The mitogen-activated protein kinase (MAPK) signaling pathway plays an important role in the regulation of cell growth, proliferation, differentiation, transformation and death. Mitogen-activated protein kinase phosphatase 1 (MKP1) has an inhibitory effect on the p38MAPK and JNK pathways, but it is unknown whether it plays a role in Aβ-induced oxidative stress and neuronal inflammation. In this study, PC12 cells were infected with MKP1 shRNA, MKP1 lentivirus or control lentivirus for 12 hours, and then treated with 0.1, 1, 10 or 100 μM amyloid beta 42 (Aβ42). The cell survival rate was measured using the cell counting kit-8 assay. MKP1, tumor necrosis factor-alpha (TNF-α) and interleukin-1β (IL-1β) mRNA expression levels were analyzed using quantitative real time-polymerase chain reaction. MKP1 and phospho-c-Jun N-terminal kinase (JNK) expression levels were assessed using western blot assay. Reactive oxygen species (ROS) levels were detected using 2′,7′-dichlorofluorescein diacetate. Mitochondrial membrane potential was measured using flow cytometry. Superoxide dismutase activity and malondialdehyde levels were evaluated using the colorimetric method. Lactate dehydrogenase activity was measured using a microplate reader. Caspase-3 expression levels were assessed by enzyme-linked immunosorbent assay. Apoptosis was evaluated using the terminal deoxynucleotidyl transferase dUTP nick end labeling method. MKP1 overexpression inhibited Aβ-induced JNK phosphorylation and the increase in ROS levels. It also suppressed the Aβ-induced increase in TNF-α and IL-1β levels as well as apoptosis in PC12 cells. In contrast, MKP1 knockdown by RNA interference aggravated Aβ-induced oxidative stress, inflammation and cell damage in PC12 cells. Furthermore, the JNK-specific inhibitor SP600125 abolished this effect of MKP1 knockdown on Aβ-induced neurotoxicity. Collectively, these results show that MKP1 mitigates Aβ-induced apoptosis, oxidative stress and neuroinflammation by inhibiting the JNK signaling pathway, thereby playing a neuroprotective role.

The rheo-squeeze casting (RSC) process is a newly-developed casting process for high-performance components. In order to further improve the mechanical properties of magnesium alloys, AZ91-2wt.%Ca (AZX912) alloy was prepared by the RSC process and then subjected to heat treatment. The microstructure evolution and mechanical properties of AZX912 alloy during heat treatment were investigated. It was found that during solid solution treatment at 410 °C, β-Mg17Al12 phase with low melting point dissolves into α-Mg matrix, while the connected network-like Al2Ca phase with high melting point tends to separate gradually, and the tips of Al2Ca phase is partially spheroidized. With the increase of solid solution time, the yield strength (YS) of AZX912 alloy decreases gradually while the ultimate tensile strength (UTS) and elongation to failure (Ef) increase continuously. Isothermal ageing at 225 °C promotes the precipitation of β-Mg17Al12 phase in the matrix of AZX912 alloy. The hardness reaches the peak after ageing for 96 h and the increase in hardness is about 24.8%. The precipitation of β-Mg17Al12 phase during ageing treatment is beneficial to YS but harmful to Ef. The mechanism of microstructure evolution during heat treatment and its effect on mechanical properties are discussed.

Abstract The eukaryotic P-stalk contains two P1-P2 protein dimers with a conserved C- terminal domain (CTD) critical for the interaction with external factors. To understand the role of the individual CTD of human P1/P2 proteins, we examined the interaction of reconstituted human P-protein complexes and C-terminally truncated forms with ricin A chain (RTA), which binds to the stalk to depurinate the sarcin/ricin loop (SRL). The interaction between P-protein complexes and RTA was examined by surface plasmon resonance, isothermal titration calorimetry, microscale thermophoresis and bio-layer interferometry. The P1-P2 heterodimer missing a CTD on P2 was able to bind RTA. In contrast, the P1-P2 heterodimer missing the CTD of P1 protein displayed almost no binding toward RTA. Very low interaction was detected between RTA and the non-truncated P2-P2 homodimer, suggesting that the structural architecture of the P1-P2 heterodimer is critical for binding RTA. The reconstituted pentameric human stalk complex had higher affinity for RTA than the P1-P2 dimer. Deletion of P1 CTD, but not P2 CTD reduced the affinity of the pentamer for RTA. These results highlight the importance of the heterodimeric organization of P1-P2 in the human stalk pentamer and functional non-equivalence of the individual P-protein CTDs in the interaction with RTA.

The orbital riveting process has been successively adopted in the assembly of wheel hub bearing, due to its special merits of high efficiency, low cost, and so on. The forming process and deformation behavior of the inner ring have significant influence on the axial clamping force and bearing clearance, however, which haven’t been addressed yet. In this study, a numerical simulation platform for the assembly of the hub bearing is established by the joint use of the static implicit and dynamic explicit algorithms. Based on the platform, the deformation process and deformation behavior of the inner ring are investigated, along with the interference assembly and riveting assembly on the loading process of the inner ring. Finally, relevant experimental verifications are carried out to consolidate the simulation results. The research findings could be used to guide the design and optimization of the axial clamping force and bearing clearance.

Previous studies have shown that up-regulation of transforming growth factor β1 results in neuroprotective effects. However, the role of the transforming growth factor β1 downstream molecule, SMAD2/3, following ischemia/reperfusion remains unclear. Here, we investigated the neuroprotective effects of SMAD2/3 by analyzing the relationships between SMAD2/3 expression and cell apoptosis and inflammation in the brain of a rat model of cerebral ischemia/reperfusion. Levels of SMAD2/3 mRNA were up-regulated in the ischemic penumbra 6 hours after cerebral ischemia/reperfusion, reached a peak after 72 hours and were then decreased at 7 days. Phosphorylated SMAD2/3 protein levels at the aforementioned time points were consistent with the mRNA levels. Over-expression of SMAD3 in the brains of the ischemia/reperfusion model rats via delivery of an adeno-associated virus containing the SMAD3 gene could reduce tumor necrosis factor-α and interleukin-1β mRNA levels, down-regulate expression of the pro-apoptotic gene, capase-3, and up-regulate expression of the anti-apoptotic protein, Bcl-2. The SMAD3 protein level was negatively correlated with cell apoptosis. These findings indicate that SMAD3 exhibits neuroprotective effects on the brain after ischemia/reperfusion through anti-inflammatory and anti-apoptotic pathways.

This paper presents an analytic derivation for the time-domain transmission across layered mediums. The transmission coefficient and attenuation coefficient are obtained in the time-domain from general electromagnetic theory. The transmission electric field can be obtained within a few seconds by convolving the coefficients with incident EMP. The results are accordant with the FDTD method, and this approach can deal with the multilayer mediums problem. The limitations of this approach are discussed in this paper.

Ricin A chain (RTA) depurinates the sarcin/ricin loop (SRL) by interacting with the C-termini of the ribosomal P stalk. The ribosome interaction site and the active site are located on opposite faces of RTA. The interaction with P proteins allows RTA to depurinate the SRL on the ribosome at physiological pH with an extremely high activity by orienting the active site towards the SRL. Therefore, if an inhibitor disrupts RTA–ribosome interaction by binding to the ribosome binding site of RTA, it should inhibit the depurination activity. To test this model, we synthesized peptides mimicking the last 3 to 11 amino acids of P proteins and examined their interaction with wild-type RTA and ribosome binding mutants by Biacore. We measured the inhibitory activity of these peptides on RTA-mediated depurination of yeast and rat liver ribosomes. We found that the peptides interacted with the ribosome binding site of RTA and inhibited depurination activity by disrupting RTA–ribosome interactions. The shortest peptide that could interact with RTA and inhibit its activity was four amino acids in length. RTA activity was inhibited by disrupting its interaction with the P stalk without targeting the active site, establishing the ribosome binding site as a new target for inhibitor discovery.

Indoor microclimate is important for crop production and quality in greenhouse cultivation. This paper focuses on microclimate study based on a computational fluid dynamics (CFD) model of a typical plastic greenhouse (with a sector shape vertical cross-section) popularly used in central China. A radiation model is added into the CFD model so as to simulate coupling of convective transfers and radiative exchanges at the cover and the roof, instead of using the usual coupling approach based on energy balance. In addition, a fractal permeability model is innovatively adopted in the modeling of the crop canopy. Compared the numerical results with measured experimental data, the model simulation is proved with success. This model then is used to explore the microclimate variable distributions in the greenhouse. It shows that the airflow pattern, temperature and humidity profiles are different from those in a sawtooth Mediterranean-type greenhouse. The study suggests that this deliberately developed CFD model can be served as a useful tool in macroclimate research and greenhouse design investigating.

Automatic Generation Control (AGC) and Automatic Voltage Control (AVC) are key approaches to frequency and voltage regulation in power systems. However, based on the assumption of decoupling of active and reactive power control, the existing AGC and AVC systems work independently without any coordination. In this paper, a concept and method of hybrid control is introduced to set up an Integrated Coordinated Optimization Control (ICOC) system for AGC and AVC. Concerning the diversity of control devices and the characteristics of discrete control interaction with a continuously operating power system, the ICOC system is designed in a hierarchical structure and driven by security, quality and economic events, consequently reducing optimization complexity and realizing multi-target quasi-optimization. In addition, an innovative model of Loss Minimization Control (LMC) taking into consideration active and reactive power regulation is proposed to achieve a substantial reduction in network losses and a cross iterative method for AGC and AVC instructions is also presented to decrease negative interference between control systems. The ICOC system has already been put into practice in some provincial regional power grids in China. Open-looping operation tests have proved the validity of the presented control strategies.

Ribosome-inactivating proteins (RIPs) are potent toxins that inactivate ribosomes by catalytically removing a specific adenine from the α-sarcin/ricin loop (SRL) of the large rRNA. Direct assays for measuring depurination activity and indirect assays for measuring the resulting translation inhibition have been employed to determine the enzyme activity of RIPs. Rapid and sensitive methods to measure the depurination activity of RIPs are critical for assessing their reaction mechanism, enzymatic properties, interaction with ribosomal proteins, ribotoxic stress signaling, in the search for inhibitors and in the detection and diagnosis of enteric infections. Here, we review the major assays developed for measuring the catalytic activity of RIPs, discuss their advantages and disadvantages and explain how they are used in understanding the catalytic mechanism, ribosome specificity, and dynamic enzymatic features of RIPs.

Horizontal well (HW) was divided into several elements after acidizing. In each element, there would exist a composite zone that was made up of damage zone (DZ) and acidizing zone (AZ). Local skin factor after acidizing was used to describe the resistance in each composite zone. The models for local skin factor and productivity of HW were created using the method of equivalent filtration resistance and displacement between two similar flow modes. According to the solution of the models, type curves of skin factor and production-increasing ratio after acidizing were illustrated, and the effect of different parameters in DZ and AZ on distribution of skin factor and production-increasing ratio after acidizing were discussed. The present model has a significant guide on the practice of acidizing technology.

After multistage fracturing, the flowback of fracturing fluid will cause two-phase flow through hydraulic fractures in shale gas reservoirs. With the consideration of two-phase flow and desorbed gas transient diffusion in shale gas reservoirs, a two-phase transient flow model of multistage fractured horizontal well in shale gas reservoirs was created. Accurate solution to this flow model is obtained by the use of source function theory, Laplace transform, three-dimensional eigenvalue method, and orthogonal transformation. According to the model’s solution, the bilogarithmic type curves of the two-phase model are illustrated, and the production decline performance under the effects of hydraulic fractures and shale gas reservoir properties are discussed. The result obtained in this paper has important significance to understand pressure response characteristics and production decline law of two-phase flow in shale gas reservoirs. Moreover, it provides the theoretical basis for exploiting this reservoir efficiently.

During the development of water drive gas reservoirs, the phenomena of gas escaping from water and water separating out from gas will change the seepage characteristics of formation fluid. Therefore, the traditional gas-water two-phase inflow performance relationship (IPR) models are not suitable for calculating the water producing gas well inflow performance relationship in water drive gas reservoirs. Based on the basic theory of fluid mechanics in porous medium, using the principle of mass conservation, and considering the process of dissolution and volatilization of gas and water formation, this paper establishes a new mathematical model of gas-water two-phase flow. Multiobjective optimization method is used to automatically match the sample well production data in water drive gas reservoirs and then we can achieve the sample well’s productivity equation, relative permeability curve, water influx intensity, and single well controlled reserves. In addition, the influence of different production gas water ratios (GWR) and gas-soluble water coefficients on absolute open flow rate (qAOF) is discussed. This method remedied the limitation of well testing on site and was considered to be a new way to analyze the production behaviors in water producing gas well.

Ricin A chain (RTA) undergoes retrograde trafficking and is postulated to use components of the endoplasmic reticulum (ER) associated degradation (ERAD) pathway to enter the cytosol to depurinate ribosomes. However, it is not known how RTA evades degradation by the proteasome after entry into the cytosol. We observed two distinct trafficking patterns among the precursor forms of wild type RTA and nontoxic variants tagged with enhanced green fluorescent protein (EGFP) at their C-termini in yeast. One group, which included wild type RTA, underwent ER-to-vacuole transport, while another group, which included the G83D variant, formed aggregates in the ER and was not transported to the vacuole. Peptide: N-glycanase (Png1), which catalyzes degradation of unfolded glycoproteins in the ERAD pathway affected depurination activity and toxicity of wild type RTA and G83D variant differently. PreG83D variant was deglycosylated by Png1 on the ER membrane, which reduced its depurination activity and toxicity by promoting its degradation. In contrast, wild type preRTA was deglycosylated by the free pool of Png1 in the cytosol, which increased its depurination activity, possibly by preventing its degradation. These results indicate that wild type RTA has a distinct requirement for Png1 compared to the G83D variant and is deglycosylated by Png1 in the cytosol as a possible strategy to avoid degradation by the ERAD pathway to reach the ribosome.

A dual fractal reservoir transient flow model was created by embedding a fracture system simulated by a tree-shaped fractal network into a matrix system simulated by fractal porous media. The dimensionless bottom hole pressure model was created using the Laplace transform and Stehfest numerical inversion methods. According to the model's solution, the bilogarithmic type curves of the dual fractal reservoirs are illustrated, and the influence of different fractal factors on pressure transient responses is discussed. This semianalytical model provides a practical and reliable method for empirical applications.

Epidemiological studies have demonstrated that type 2 diabetes mellitus (T2DM) and hyperinsulinemia are associated closely with endometrial carcinoma risk, although the molecular mechanism remains unclear. Insulin receptor isoformA expression is upregulated in many cancer cells and tissues, which suggests that IR-A-mediated signaling pathways may have important implications for cancer pathogenesis. We measured the expression of insulin receptor isoforms (IR-A and IR-B in the normal endometrium tissues, the endometrial carcinoma tissues and the endometrial carcinoma cell lines. We found that the total insulin receptor (IR) and IR-A expression mRNA levels and the ratio of IR-A to total IR in endometrial carcinoma specimens were significantly higher than them in control endometrial tissue specimens(P

In the title compound, [CrCl3(C19H13Br2N3)], the Cr3+ ion is coordinated by the tridentate 2,6-bis[(4-bromophenyl)iminomethyl]pyridine Schiff base ligand in a fac-octahedral geometry. The dihedral angles between the pyridine and benzene rings are 23.9 (6) and 70.7 (1)°.

In the molecule of the title compound, [FeCl2(C25H19N3)], the three N atoms span the axial–equatorial–axial sites of the trigonal-bipyramidal coordination polyhedron; the geometry of the FeII atom is 32% distorted from trigonal-bipyramidal (towards square-pyramidal along the Berry pseudorotation pathway). One of the Cl atoms is disordered over two positions in a 0.938 (11):0.062 (11) ratio. Intermolecular C—H...Cl hydrogen bonding occurs in the crystal structure.

The title compound, [CuCl2(C21H19N3)], lies on a twofold rotation axis that passes through the Npyridyl—Cu bond; this symmetry element relates one half of the organic ligand to the other as well as one Cl ligand to the other. The three N atoms span the axial–equatorial–axial sites of the trigonal-bipyramidal coordination polyhedron; the geometry of the CuII atom is 31% distorted from trigonal-bipyramidal (towards square-pyramidal along the Berry pseudorotation pathway).

In the title compound, {[Cd(C8H4O4)(C11H6N2O)(H2O)3]·2H2O}n, the CdII atom is seven-coordinated by two N atoms from the phenanthroline-derived 4,5-diazafluorene-9-one ligand, two O atoms from one bidentate benzene-1,3-dicarboxylate ligand and three O atoms from the three water molecules in a distorted pentagonal-bipyramidal arrangement. Moreover, there are two dissociative water molecules in each unit. Neighbouring units interact through π–π interactions [centroid–centroid distances = 3.325 (3) and 3.358 (4) Å] and O—H...O hydrogen-bonding, resulting in a two-dimensional network extending parallel to (001).

In the title compound, [Co(C14H8O4)(C18H10N4)]n, the CoII atom is six-coordinated by four O atoms from two different biphenyl-2,2′-dicarboxylate ligands and two N atoms from the bidentate dipyrido[3,2-a:2′,3′-c]phenazine ligand in a distorted octahedral geometry. The CoII atoms are bridged by the biphenyl-2,2′-dicarboxylate ligands to form a one-dimensional chain structure. π–π interactions between neighbouring chains result in a two-dimensional supramolecular network (centroid-to-centroid separation = 3.381 Å).

It has been shown that the maintenance condition for a crystalline beam requires that there be no resonance between the crystal’s phonon frequencies, and the frequency associated with a beam moving through a lattice of N_{sp} periods. This resonance can be avoided provided that the phonon frequencies all are below half the lattice frequency. Here, we study in detail the phonon modes of several crystalline beams. The analytic results obtained in the smooth approximation are compared with numerical evaluations employing Fourier transform of the molecular dynamics (MD) modes. The stability of various crystalline structures is examined through systematic MD simulations based on several different lattice designs. The maintenance condition, when combined with either the simple analytic theory or the numerical evaluation of phonon modes, exhibits excellent agreement with the MD calculations of crystal stability. A confirmed maintenance condition, derived from linear-resonance criteria, is that the lattice frequency must not equal the sum of any two phonon frequencies.