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Metal sulfides have attracted much attentions as anode materials for lithium-ion batteries (LIBs) because of the high theoretical capacity. However, the poor electronic conductivity and large volume variation usually give rise to the rapid capacity decay and undesirable rate performance, severely hampering their practical application. Herein, a gradient selenium-doped hollow sandwich structured zinc sulfide/carbon (ZnS/C) composite (Se-HSZC) is designed and fabricated as long life-span and stable anode material for LIBs. The gradient Se-doping enhances the interfacial charge transfer in Se-HSZC, while the unique double carbon shell sandwich structure further greatly reduces the volume expansion and ensures the electron fast transportation. Consequently, the Se-HSZC anode presents outstanding rate capability (654 mAh g−1 at 2 A g−1) with remarkable reversible capacity (567 mAh g−1 after 1500 cycles at 4 A g−1) for the half battery. In particular, a reversible capacity of 457 mAh g−1 at 0.5 A g−1 is achieved after 50 cycles for the full battery with LiNi0.6Co0.2Mn0.2O2 as cathode. This work offers a promising design route of novel metal sulfides nanostructures for high performance LIBs.

In this paper, aiming at the problem that the ideal modeling point of the foot end deviates from the actual contact point due to the rolling effect of the semi-cylindrical foot end in leg hydraulics drive system (LHDS), a novel and relatively simple kinematics and statics correction algorithm is proposed. This algorithm can effectively improve the accuracy of LHDS kinematics and statics, and it is still applicable when the body and the contact surface are at different angles. Firstly, this paper deduces the kinematics and statics when the foot end of LHDS is regarded as the point foot, analyzes and calculates the deviation under common working conditions. Secondly, in view of this phenomenon, a kinematics correction algorithm based on virtual DOF and a statics correction algorithm based on translation theorem of forces are proposed respectively. Finally, the proposed algorithm is verified by LHDS performance test platform under various working conditions. The results show that after applying the kinematics correction algorithm, the trajectory deviation reduction rate of the hip joint is over 65%; after applying the statics correction algorithm, the deviation reduction rate of foot end contact force is over 43%. The related research results can be applied to any similar foot end, which has engineering application value.

Assembly of the adenovirus capsid protein hexon depends on the assistance of the molecular chaperone L4-100K. However, the chaperone mechanisms remain unclear. In this study, we found that L4-100K was involved in the hexon translation process and could prevent hexon degradation by the proteasome in cotransfected human cells. Two nonadjacent domains, 84-133 and 656-697, at the N-terminal and C-terminal regions of human adenovirus type 5 L4-100K, respectively, were found to be crucial and cooperatively responsible for hexon trimer expression and assembly. These two chaperone-related domains were conserved in the sequence of L4-100K and in the function of hexon assembly across different adenovirus serotypes. Different degrees of cross-activity of hexon trimerization with different serotypes were detected in subgroups B, C, and D, which were proven to be controlled by the interaction between the C-terminal chaperone-related domain of L4-100K and hypervariable regions (HVR) of hexon. Additionally, HVR-chimeric hexon mutants were successfully assembled with the assistance of the 1-697 mutant. Structural analysis of 656-697 by nuclear magnetic resonance and structural prediction of L4-100K using Robetta showed that the two conserved domains are mainly composed of α-helices and are located on the surface of the highly folded core region. Our research provides a more complete understanding of hexon assembly and guidance for the development of hexon-chimeric adenovirus vectors that will be safer, smarter, and more efficient. IMPORTANCE Adenovirus vectors have been widely used in clinical trials of vaccines and gene therapy, although some deficiencies remain. Chimeric modification of the hexon was expected to improve the potency of preexisting immune evasion and targeting, but in many cases, viral packaging is prevented by the inability of the chimeric hexon to assemble correctly. So far, few studies have examined the mechanisms of hexon trimer assembly. Here, we show how the chaperone protein L4-100K contributes to the assembly of the adenovirus capsid protein hexon, and these data will provide a guide for novel adenovirus vector design and development, as we desired.

Previous lectures have shown that to effectively explore Taiwan’s climate change or other relevant topics, long-term and stable observation datasets are required. We introduce the high-resolution grided precipitation dataset (TCCIP_PR), which was constructed by the Taiwan Climate Change projection and adaptation Information Platform (TCCIP) program from thousands of station records. Although, a high spatial-time relationship exists between the TCCIP_PR and the stations, a large uncertainty occurs over the complex terrain on the southwest windward side during the summer, due to sparse stations. To better understand the change in the extreme rainfall trends, we analyze 9 suitable indices from the Expert Team on Climate Change Detection and Indices (ETCCDI). Our result show that the extreme rainfall intensity and frequency have continuously increased for a long time, and the consecutive dry days have decreased in recent decades, particularly over southwest Taiwan. The regime change evaluations agree that the precipitation characteristics were amplified and become more unpredictable from the early (1960–2002) to the late (2003–2017) period. For future applications or research, the calculated results of the extreme indices can be found in the printed documentation and the online retrieval system.

Atmospheric aerosol nucleation contributes to around half of cloud condensation nuclei globally. Despite the importance for climate, detailed nucleation mechanisms are still poorly understood. Understanding aerosol nucleation dynamics is hindered by non-reactivity of force fields and high computational costs due to rare event nature of aerosol nucleation. Developing reactive force fields for nucleation systems are even more challenging than covalently bonded materials because of wide size range and high dimensional characteristics of non-covalent hydrogen bonding bridging clusters. Here we proposes a system transferable framework to train an accurate reactive force field (FF) based on deep neural network (DNN) and further bridges the DNN-FF based molecular dynamics (MD) with cluster kinetics model based on Poisson distributions of reactive events to overcome high computational costs from direct MD. We found that previously reported acid-base formation rates tend to be underestimated several times, emphasizing acid-base nucleation observed in multiple environments should be revisited.

A low‐profile metasurface antenna with circularly polarized radiation and tailored anisotropic reflection is proposed in this letter. The metasurface antenna composed of excitation structure (microstrip line with coupling slot) and a metasurface layer. The metasurface functions for two goals, generating circularly polarized wave for radiation and tailoring reflection phase for scattering, respectively. The overall structure of the metasurface antenna is compact with a dimension of 0.67λ × 0.67λ × 0.05λ at 5 GHz. Numerical and measured results confirm that the metasurface antenna exhibits 11.1% −10 dB S11 bandwidth from 4.68 to 5.23 GHz, 10.8% 3 dB axial ratio bandwidth from 4.782 to 5.37 GHz and a maximum gain of 6.83 dBic. Besides, the metasurface antenna achieves anti‐phase reflection under orthogonal polarized incident waves at around 5 GHz. To demonstrate a potential application, 16 identical metasurface antennas are put in a 4 × 4 array. The metasurface antenna array achieves directive circularly polarized radiation with a maximum gain of 15 dBic. On the other hand, when under normal illumination, the scattering field of metasurface antenna array is redistributed due to phase cancelation, so that the backward radar cross section of the array is significantly reduced, which is applicable for military platform.

Though sulfuric acid and ammonia/alkyl amines are recognized as main contributors to new particle formation (NPF), models and observations have indicated that other organic species may be involved. In this study we introduced a suitable flow tube system to investigate the effect of formaldehyde (CH2O) on NPF from sulfuric acid and water at 297 K. Our results showed that nucleation rates are slightly enhanced when adding CH2O of 0.31–2.40 ppbv (in the range of atmospheric CH2O peak concentration) to stable sulfuric acid and water system at relative humidity (RH) of 30%, i.e., a rise of the particle number only by a factor of about 2, which is small in comparison to the millionfold increase caused by methylamine in similar conditions. And the promoting effect was weak under different RH. Cluster growth flux at experimental conditions, obtained from quantum chemistry-based cluster evaporation rate constants applied in a cluster population dynamics model, showed H2SO4-CH2O-based clusters are hard to grow. Therefore, the effect of CH2O on NPF via directly involving in the nucleation can be eliminated. In addition, the derived information may provide new insight into the impact of aldehydes on NPF.

In coastal regions and ocean areas, methanesulfonic acid (MSA; CH3SO3H) is present in considerable concentrations in the gas-phase and aerosols. It has been shown that MSA could contribute to growth and possibly form initial molecular cluster, which may lead to aerosol formation. However, quantitative concentrations and thermodynamic properties of MSA and sulfuric acid (SA; H2SO4) in the presence of water (W; H2O) remain largely uncertain. In this study, flow tube reactor was used to investigate the effects of each reactant on new particle formation (NPF) in a multi-component system consisting of MSA, SA, and W. Particles were measured for different combinations of reactants. It showed that a different order for reactant addition led to different experimental results, where the added MSA vapor to the SA-W binary system presented an obvious bimodal structure, for ternary system with SA added to the MSA-W, the similar bimodal phenomenon was not observed. The composition of clusters in the air flow was further analyzed by the commercial Atmospheric Pressure Interface Time-of-Flight Mass Spectrometer (APi-TOF-MS, Tofwerk AG), which is equipped with a homemade chemical ionization (CI) source, mass peaks corresponding to clusters that contain smaller MSA or SA molecules were clearly observed, indicating that these clusters are exist and stable. In addition, quantum chemistry calculation-based evaporation rate values were applied in a cluster dynamics model to yield formation rates of 2.6 × 102 cm−3 s−1 and cluster concentrations under different simulation conditions. This study could provide some insight into how acids interact in the atmosphere.

The grafting density of poly(ethylene glycol) (PEG) on nanoparticle (NP) surfaces is the most important parameter determining the interaction of nanoparticles with serum proteins, the subsequent sequestration of the nanoparticle from the bloodstream by the mononuclear phagocyte system, and the eventual delivery efficiency to tumor tissues. However, the majority of in vivo studies do not characterize or report the grafting density of PEG on nanoparticles due to a lack of feasible characterization methods, making it difficult to evaluate the published studies and reconcile apparent conflicting results. Herein, we develop a facile and non-sacrificial 1H NMR analytical approach for the quantitative characterization of grafting density of thiol-terminated PEG (HS-PEG) on gold NPs (GNPs). A multi-Lorentzian-splitting algorithm is used to distinguish the NMR signal of free PEG from those of the grafted ones, therefore allowing in situ monitoring of the grafting process to study the effects of GNP sizes, PEG molecular weights and NP capping ligands on grafting rates and grafting densities. The main advantage of this method is that it is not limited by the types of terminal functional groups on PEG, surface chemistry of the nanoparticles or their composition. It also provides a set of critical and standard guides for characterization of the PEG grafting density on nanoparticles for in vivo biological and biomedical studies.

An acceptor plane expansion approach is demonstrated to selectively improve horizontal dipole orientation of TADF emitters., Manipulating orientation of organic emitters remains a formidable challenge in organic light-emitting diodes (OLEDs). Here, expansion of the acceptor plane of thermally activated delayed fluorescence (TADF) emitters was demonstrated to selectively modulate emitting dipole orientation. Two proof-of-the-concept molecules, PXZPyPM and PXZTAZPM, were prepared by introducing a planar 2-phenylpyridine or 2,4,6-triphenyl-1,3,5-triazine substituent into a prototypical molecule (PXZPM) bearing a pyrimidine core and two phenoxazine donors. This design approach suppressed the influence of substituents on electronic structures and associated optoelectronic properties. Accordingly, PXZPyPM and PXZTAZPM preserved almost the same excited states and similar emission characteristics as PXZPM. The expanded acceptor plane of PXZPyPM and PXZTAZPM resulted in a 15 to 18% increase in horizontal ratios of emitting dipole orientation. PXZPyPM supported its green device exhibiting an external quantum efficiency of 33.9% and a power efficiency of 118.9 lumen per watt, competitive with the most efficient green TADF OLEDs reported so far.

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and is an emerging disease. There has been a rapid increase in cases and deaths since it was identified in Wuhan, China, in early December 2019, with over 4,000,000 cases of COVID-19 including at least 250,000 deaths worldwide as of May 2020. However, limited data about the clinical characteristics of pregnant women with COVID-19 have been reported. Given the maternal physiologic and immune function changes during pregnancy, pregnant women may be at a higher risk of being infected with SARS-CoV-2 and developing more complicated clinical events. Information on severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) may provide insights into the effects of COVID-19's during pregnancy. Even though SARS and MERS have been associated with miscarriage, intrauterine death, fetal growth restriction and high case fatality rates, the clinical course of COVID-19 pneumonia in pregnant women has been reported to be similar to that in non-pregnant women. In addition, pregnant women do not appear to be at a higher risk of catching COVID-19 or suffering from more severe disease than other adults of similar age. Moreover, there is currently no evidence that the virus can be transmitted to the fetus during pregnancy or during childbirth. Babies and young children are also known to only experience mild forms of COVID-19. The aims of this systematic review were to summarize the possible symptoms, treatments, and pregnancy outcomes of women infected with COVID-19 during pregnancy.

Mudslides, avalanches, and mine dam-breaks can be serious disasters and cause severe damages but the detailed flow field description has not been completed yet. This paper developed a modified Bi-viscosity model (MBM) to solve the mudslide flow by adopting Bingham model (BM) and the conventional Bi-viscosity model (CBM). In both CBM and MBM, a yield strain rate is used to identify the plug and liquefied rheological prosperities. In the MBM, an extremely high plug viscosity adopted to represent the stratification effect. BM, CBM, and MBM are integrated into the Splash3D model, which solves Navier-Stokes equations with PLIC-VOF surface-tracking algorithm. The viscosity term is solved by implicit iteration. The model is carefully validated with theoretical results and laboratory data with good agreements. The Splash3D model is then used to study the failure of the gypsum tailings dam in East Texas in 1966, briefed as FGT66. A series of sensitivity analyses on the yield strain rate and grid resolution is performed. The results show that the predicted flood distance and flood speed by MBM is very close to the field data. The MBM results illustrate the process that the plug zone and liquefied zone is developed. The simulations show the initiation of the mudslide flow, the development of the slip surface, the flooding process, and the velocity ceasing process. The slip surface is developed automatically without empirical equations. By comparing the results of BM, CBM, and MBM to the field data, we conclude that the liquefied tailings are under the effect of stratification, and the stratification effect is presented in the extremely high plug viscosity in the Splash3D model.

研究依托咪酯联合瑞芬太尼对行胃肠镜检查老年患者的苏醒时间、生命体征及不良反应的影响. 选取2016-07/2017-07在浙江省桐乡市第二人民医院行胃肠镜检查的老年患者纳入260例, 根据数字表法分为观察组130例行瑞芬太尼联合依托咪酯, 对照组130例行芬太尼联合丙泊酚, 比较两组患者在不同时间段的不良反应、生命体征、苏醒时间及离室时间等. 观察组130例胃肠镜检查10 min后的舒张压(diastolic blood pressure, DBP)、收缩压(systolic blood pressure, SBP)、心率(heart rate, HR)及脉搏氧饱和度(pulse oximetry, SpO2), 的水平较检查前无显著性差异(P>0.05); 对照组130例行胃肠镜检查10 min后的DBP、SBP、HR及SpO2的水平较观察组增高, 与检查前比较有明显降低(P

Methanesulfonic acid (MSA) is believed to play an important role in the formation and growth of atmospheric organic aerosols and could facilitate the binary nucleation of sulfuric acid (SA)–water (W). However, understanding of larger clusters formed by gas-phase MSA with atmospheric nucleation precursors from microscopic aspect is lacking. In this work, to study the microscopic mechanism of the ternary nucleation, the structural characteristics and thermodynamics of MSA clusters with SA in the presence of up to six W molecules have been investigated. It was found that MSA forms relatively stable clusters with SA and W molecules and that acid dissociation plays an important role. The analysis of the atmospheric relevance indicates that the heterodimer MSA–SA and monohydrated cluster MSA–SA–W1 show an obvious relative concentration in the atmosphere, and thus, these species likely participate in new particle formation (NPF). However, with an increasing number of W molecules, the concentration of clusters gradually decreases. Additionally, the minimum energy isomer of MSA–SA–W4 is predicted to possess a relatively stable configuration under the employed temperature dependence analysis, and evaporation rate analysis. The detailed non-covalent interactions of MSA-SA-Wn, n = 3–6 cluster have been thoroughly studied for the first time.

Ammonia and amines are important common trace atmospheric species that can enhance new particle formation (NPF) in the Earth’s atmosphere. However, the synergistic effect of these two bases involving nucleation is still lacking. We studied the most stable geometric structures and thermodynamics of quaternary (NH3)(CH3NH2)(H2SO4)m(H2O)n (m = 1–3, n = 0–4) clusters at the PW91PW91/6-311++G(3df,3pd) level of theory for the first time. We find that the proton transfer from H2SO4 molecule to CH3NH2 molecule is easier than to NH3 molecule in the free or hydrated H2SO4-base clusters, and thus leads to the stability. The energetically favorable formation of the (NH3)(CH3NH2)(H2SO4)m(H2O)n (n = 0–4) clusters, by hydration or attachment of base or substitution of ammonia by methylamine at 298.15 K, indicate that ammonia and methylamine together could enhance the stabilization of small binary clusters. At low RH and an ambient temperature of 298.15 K, the concentration of total hydrated (NH3)(CH3NH2)(H2SO4)2 cluster...

Succinic acid (SUA) is a common dicarboxylic acid frequently observed in aerosols. Understanding the role of succinic acid in atmospheric new particle formation is essential to study the complicated nucleation mechanism. In this study, high-precision quantum chemical calculations and atmospheric clusters dynamic code (ACDC) simulations are used to investigate the nucleation mechanism of the (SA)x(SUA)y(DMA)z (0 = x, y, z ≤ 3) multicomponent system. The most stable molecular structures show that SUA can form relatively stable clusters with the SA-DMA system by hydrogen bond and proton-transfer interactions. Similar to SA molecules, SUA can provide protons to DMA when excess DMA molecules are available. ACDC simulations indicate that SUA can contribute to the cluster formation, especially at low sulfuric acid concentration and high succinic acid concentration. Moreover, the main cluster flux out of the SUA-containing system is along the non-diagonal (the number of acid molecules is greater than that of base molecules), which is different from the pure SA-DMA system. These clusters are stable enough to be present at a fairly high concentration, and could be a platform for growth into the larger sizes. This organic acid involved cluster formation may explain high nucleation rate at low sulfuric acid concentration and high organic acid concentration.

A novel set of redox-active triazatruxene-based conjugated microporous polymers have been explored as efficient electrode materials for high-performance supercapacitors., Conjugated polymers (CPs) have been intensively explored for various optoelectronic applications in the last few decades. Nevertheless, CP based electrochemical energy storage devices such as supercapacitors remain largely unexplored. This is mainly owing to the low specific capacitance, poor structural/electrochemical stability, and low energy density of most existing CPs. In this contribution, a novel set of redox-active conjugated microporous polymers, TAT-CMP-1 and TAT-CMP-2, based on nitrogen-rich and highly conductive triazatruxene building blocks, were successfully designed and synthesized to explore their potential application as efficient and stable electrode materials for supercapacitors. Despite a moderate surface area of 88 m2 g–1 for TAT-CMP-1 and 106 m2 g–1 for TAT-CMP-2, exceptional specific capacitances of 141 F g–1 and 183 F g–1 were achieved at a current density of 1 A g–1. The resulting polymers exhibited unusually high areal specific capacitance (>160 μF cm–2), which is attributed to the pseudocapacitance resulting from redox-active structures with high nitrogen content. More importantly, the TAT-CMP-2 electrode exhibits excellent cycling stability: only 5% capacitance fading is observed after 10 000 cycles at a high current density of 10 A g–1, enabling the possible use of these materials as electrodes in electrochemical devices.

Oxalic acid and dimethylamine are the most common organic acid and base in the atmosphere, and are recognized as significant precursor species in atmospheric new particle formation.

Radiation is a widely used therapeutic method for treating breast cancer. N-dihydrogalactochitosan (GC), a biocompatible immunostimulant, is known to enhance the effects of various treatment modalities in different tumor types. However, whether GC can enhance the radiosensitivity of cancer cells remains to be explored. In this study, triple-negative murine 4T1 breast cancer cells transduced with multi-reporter genes were implanted in immunocompetent Balb/C mice to track, dissect, and identify liver-metastatic 4T1 cells. These cells expressed cancer stem cell (CSC) -related characteristics, including the ability to form spheroids, the expression of the CD44 marker, and the increase of protein stability. We then ex vivo investigated the potential effect of GC on the radiosensitivity of the liver-metastatic 4T1 breast cancer cells and compared the results to those of parental 4T1 cells subjected to the same treatment. The cells were irradiated with increased doses of X-rays with or without GC treatment. Colony formation assays were then performed to determine the survival fractions and radiosensitivity of these cells. We found that GC preferably increased the radiosensitivity of liver-metastatic 4T1 breast cancer cells rather than that of the parental cells. Additionally, the single-cell DNA electrophoresis assay (SCDEA) and &gamma, H2AX foci assay were performed to assess the level of double-stranded DNA breaks (DSBs). Compared to the parental cells, DNA damage was significantly increased in liver-metastatic 4T1 cells after they were treated with GC plus radiation. Further studies on apoptosis showed that this combination treatment increased the sub-G1 population of cells, but not caspase-3 cleavage, in liver-metastatic breast cancer cells. Taken together, the current data suggest that the synergistic effects of GC and irradiation might be used to enhance the efficacy of radiotherapy in treating metastatic tumors.

Myocardial ischemia-reperfusion (I/R) injury is caused by endothelial dysfunction and enhanced oxidative stress. The overexpression of JAZF1, a zinc finger protein, has been reported to promote cell proliferation and suppress myogenic differentiation in type 2 diabetes. However, the involvement of JAZF1 in myocardial I/R injury remains to be unclear. The current study aims to investigate the role by which JAZF1 influences cardiac microvascular endothelial cells (CMECs) in a rat model of myocardial I/R injury. A total of 50 rats were established as a myocardial I/R model to isolate CMECs, with alterations in JAZF1 expression. After that, the gain- or loss-function of JAZF1 on the proliferation, apoptosis and tube formation ability of CMECs were evaluated by a series of in vitro experiments. Results indicated that JAZF1 was down-regulated in CMECs of rats with myocardial I/R injury. After treatment with JAZF1, the levels of VEGF, Bcl-2, PDGF and p-Akt/Akt were all increased; however, the expression of Bax, caspase-3, caspase-9, p-Bad/Bad, c-caspase-3/caspase-3, c-caspase-9/caspase-9, and p-FKHR/FKHR exhibited decreased levels; CMEC proliferation and angiogenesis were increased, while cell apoptosis was attenuated. CMECs transfected with JAZF1 shRNA exhibited the contrary tendencies. The key findings of this study suggest that the over-expression of JAZF1 alleviates myocardial I/R injury by enhancing proliferation and angiogenesis of CMECs and in turn inhibiting apoptosis of CMECs via the activation of the Akt signaling pathway.

Context: A host of microRNAs have been reported to suppress tumor growth, invasion, and metastasis and play roles in neurodegeneration disorders. Moreover, microRNA changes are found in the peripheral blood, cerebrospinal fluid (CSF), and brain tissues of central nervous system diseases, including glioma, Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis, and depression. Compared with other body fluids, CSF can reflect the brain pathological processes more accurately. Aims: To understand whether microRNA expression may be misregulated in patients with PD, and further discover potential diagnostic biomarkers and promising therapeutic targets for PD. Materials and Methods: Here, through real-time reverse-transcription polymerase chain reaction (RT-PCR), we compared CSF microRNA from 15 PD patients, 11 AD patients, and 16 controls with other neurologic disorders, such as encephalitis and Guillain–Barre syndrome. Results: Finally, we identified hsa-miR-626 changes in the CSF of PD patients. The mean expression level of hsa-miR-626 was significantly reduced in the CSF of PD patients compared with AD patients and controls. Conclusions: Our approach provides a preliminary research for identifying biomarkers in the CSF that could be used for the detection, diagnosis, and monitoring of PD.

Halide ions have been received intense interest in charactering and understanding their implications in atmospheric chemistry since they are related to the ozone destruction in the stratosphere. In the current study, structures, thermodynamic properties, and spectroscopic signatures of hydrated bromide Br − (H 2 O) n (n = 1–8) clusters are thoroughly studied and compared with available studies, the new global minima were observed for the larger size Br − (H 2 O) 7,8 clusters. The numbers of isomer increase with the increasing water molecules, considering the growing complexity, the isomer populations of each size clusters are provided under a wide temperature range, it was shown that different type of structures possess different temperature dependences. In addition, the bond order of different bond types of hydrated bromide has been systematically investigated for the first time.

Amino acids are recognized as important components of atmospheric aerosols, which impact on the Earth's climate directly and indirectly. However, much remains unknown about the initial events of nucleation. In this work, the interaction of alanine [NH2CH(CH3)COOH or Ala], one of the most abundant amino acids in the atmosphere, with sulfuric acid (SA) and water (W) has been investigated at the M06-2X/6-311++G(3df, 3pd) level of theory. We have studied thermodynamics of the hydrated (Ala)(SA) core system with up to four water molecules. We found that Ala, with one amino group and one carboxyl group, can interact with H2SO4 and H2O in two directions and that it has a high cluster stabilizing effect similar to that of ammonia, which is one of the key nucleation precursor. The corresponding Gibbs free energies of the (Ala)(SA)(W)n (n = 0-4) clusters formation at 298.15 K predicted that Ala can contribute to the stabilization of small binary clusters. Our results showed that the hydrate distribution is temperature-dependent and that a higher humidity and temperature can contribute to the formation of hydrated clusters.

Amines have been proposed to participate in the nucleation process, but the electron density analysis and the determination of a temperature dependence of the clusters are still lacking. In this study, the clusters of (H2SO4)m(CH3NHCH3)n (m = 1–2, n = 1–3) are studied using the basin-hopping method coupled with density functional theory (DFT). Considering the high flexibility and complexity of a hydrogen bonding environment, the temperature dependence of the conformational population and the relative population fraction of the clusters are investigated. Moreover, the electron density is analyzed to identify the different types of intra-cluster interactions. The results indicate that the ratio between acid and base is very important for the cluster formation. The main interaction type changes from hydrogen bonding to a weak attraction as the number of bases increase. When the number of dimethylamine molecules is less than or equal to that of the sulfuric acid molecules as the most abundant clusters in the atmosphere, we tentatively suggest that the cluster contains less than two dimethylamine molecules because the critical clusters contain two or fewer sulfuric acid molecules. This means that the sulfuric acid–dimethylamine system can only form three main small clusters in the real atmosphere. Thus, other substances, such as water or organic acids, may be involved to promote the growth of clusters, and they may also affect the nucleation. This work predicts the possible forms of dimethylamine with sulfuric acid when participating in nucleation in a theoretical approach, and provides a reliable reference for the research on the nucleation mechanism containing dimethylamine in the atmosphere.

A previous study of the binary system (H2C2O4)(NH3)n (n = 1–6) suggested that an oxalic acid–ammonia complex may participate in atmospheric aerosol formations. However, the mechanism of the hydration of these cores is poorly understood. In this study, the hydration of (H2C2O4)(NH3) and (H2C2O4)(NH3)2 cores with up to three water molecules is investigated with respect to different routes of formation. The results may improve understanding of the nucleation of clusters containing oxalic acid in the atmosphere. Acid dissociation is found to occur during the hydration process, leading to a HC2O4−/NH4+ ion pair. In contrast with the (H2C2O4)(NH3)2 core, water molecules appear to be unfavorable with regard to the formation of hydrates with a (H2C2O4)(NH3) core; additionally, temperature is found to affect the formation of clusters and the distributions of different isomers with the same size, but the impact of relative humidity on the hydrates seems insignificant, implying that the formation of these clusters may be more favorable under cold ambient conditions. The monohydrates and dihydrates of the (H2C2O4)(NH3)2 core may be relatively extensive in (H2C2O4)(NH3)m(H2O)n (m = 1–2, n = 1–3) clusters and may contribute to the atmospheric nucleation. Furthermore, this study presents a first attempt at determining the Rayleigh scattering properties of oxalic acid–ammonia–water pre-nucleation clusters; the results show that adding a water molecule could effectively increase the Rayleigh scattering intensity, but a single ammonia molecule may be able to generate a larger increase in the Rayleigh light scattering intensity than a water molecule. This may also indicate that clusters containing oxalic acid and ammonia show high Rayleigh light scattering intensities, but the more ammonia molecules there are in clusters, the higher the Rayleigh light scattering intensity and the greater the contribution to the extinction properties.

This paper incorporates the Bingham rheology model with the Navier&ndash, Stokes solver to simulate the tsunamis excited by a slump-type landslide. The slump is modeled as the Bingham material, in which the rheological properties changing from the un-yield phase to yield phase is taken into account. The volume of fluid method is used to track the interfaces between three materials: air, water, and slump. The developed model is validated by the laboratory data of the benchmark landslide tsunami problem. A series of rheological properties analyses is performed to identify the parameter sensitivity to the tsunami generation. The results show that the yield stress plays a more important role than the yield viscosity in terms of the slump kinematics and tsunami generation. Moreover, the scale effect is investigated under the criterion of Froude number similarity and Bingham number similarity. With the same Froude number and Bingham number, the result from the laboratory scale can be applied to the field scale. If the slump material collected in the field is used in the laboratory experiments, only the result of the maximum wave height can be used, and significant errors in slump shape and moving speed are expected.

This paper incorperates Bingham and bi-viscosity rheology models with the Navier&ndash, Stokes solver to simulate the dynamics and kinematics processes of slumps for tsunami generation. The rheology models are integrated into a computational fluid dynamics code, Splash3D, to solve the incompressible Navier&ndash, Stokes equations with volume of fluid surface tracking algorithm. The change between un-yield and yield phases of the slide material is controlled by the yield stress and yield strain rate in Bingham and bi-viscosity models, respectively. The integrated model is carefully validated by the theoretical results and laboratory data with good agreements. This validated model is then used to simulate the benchmark problem of the failure of the gypsum tailings dam in East Texas in 1966. The accuracy of predicted flood distances simulated by both models is about 73% of the observation data. To improve the prediction, a fixed large viscosity is introduced to describe the un-yield behavior of tailings material. The yield strain rate is obtained by comparing the simulated inundation boundary to the field data. This modified bi-viscosity model improves not only the accuracy of the spreading distance to about 97% but also the accuracy of the spreading width. The un-yield region in the modified bi-viscosity model is sturdier than that described in the Bingham model. However, once the tailing material yields, the material returns to the Bingham property. This model can be used to simulate landslide tsunamis.

Atmospheric aerosols are closely related to weather, climate and human health, and New particle formation (NPF) is a major source of atmospheric aerosols. Currently, some field observations and experiments indicate that acetic acid (HOAc) could be involved in NPF events. However, mechanism of acetic acid nucleation is still unclear. In this study, the low-lying structures and thermodynamics of acetic acid (HOAc)-dimethylamine (DMA)-water (W) system were studied at PW91PW91/6–311++G (3df, 3pd) level. We found that acetic acid forms relatively stable clusters with dimethylamine, and that proton transfer enhances the strength of the hydrogen bond in (HOAc) (DMA) (H2O)n (n = 2–4) clusters. Temperature has an important effect on the distribution of isomers, especially for (HOAc) (DMA) (H2O)2 clusters. Besides, all the isomers contribute to the nucleation of clusters. The various RH has a negligible effect on the hydrate distribution. However, the non-hydrated clusters are always dominant and they are easy to form stable cluster, as seen from the comparison of hydrate distributions and cluster formation rates. The above analyses indicate that (HOAc) (DMA) is relatively stable and some larger clusters based on (HOAc) (DMA) may participate in new particle formation.

Although uncommon, radial artery access site complications are likely to become more frequent with the increased adoption of transradial cardiac catheterization, the incidence of radial artery pseudoaneurysm (PSA) has also increased. The treatments for radial artery PSA include ultrasound-guided radial artery compression, ultrasound-guided percutaneous thrombin injection, and surgical repair. This report is about a delayed radial artery PSA patient after percutaneous coronary intervention (PCI), treated by manual radial artery compression under the real-time monitoring of color Doppler ultrasound (CDU); the effect was significant.

Sheep is an important livestock in the world providing meat, milk and wool for human beings. With increasing human population, the worldwide needs of production of sheep have elevated. To meet the needs, the assistant reproductive technology including ovine in vitro embryo production (ovine IVP) is urgently required to enhance the effective production of sheep in the world. To learn the status of ovine IVP, we collected some publications related to ovine IVP through PubMed and analyzed the progress in ovine IVP made in the last five years (2012–2017). We made comparisons of these data and found that the recent advances in ovine IVP has been made slowly comparable to that of ovine IVP two decades ago. Therefore, we suggested two strategies or approaches to tackle the main problems in ovine IVP and expect that the efficiency of ovine IVP could be improved significantly when the approaches would be implemented.

The presence of amines can increase aerosol formation rates. Most studies have been devoted to dimethylamine as the representative of amine; however, there have been a few works devoted to methylamine. In this study, theoretical calculations are performed on CH3NH2(H2SO4)m(H2O)n (m = 0-3, n = 0-3) clusters. In addition to the structures and energetics, we focused on determining the following characteristics: (1) the growth mechanism, (2) the hydrate distributions and the influences of humidity and temperature, (3) Rayleigh scattering properties. We explored the cluster growth mechanism from a thermodynamics aspect by calculating the Gibbs free energy of adding a water or sulfuric acid molecule step by step at three atmospherically relevant temperatures. The relative ease of the reaction at each step is discussed. From the analysis of hydrate distributions, we find that CH3NH2(H2SO4)(H2O)2, CH3NH2(H2SO4)2, and CH3NH2(H2SO4)3 are most likely to exist in the atmosphere. The general trend of hydration in all cases is more extensive with the growing relative humidity (RH), whereas the distributions do not significantly change with the temperature. Analysis of the Rayleigh scattering properties showed that both H2SO4 and H2O molecules could increase the Rayleigh scattering intensities and isotropic mean polarizabilities, with greater influence by the sulfuric acid molecules. This work sheds light on the mechanism for further research on new particle formation (NPF) containing methylamine in the atmosphere.

Amines have been recognized as important precursor species in the formation of new atmospheric particles. Although dimethylamine–water clusters have been the focus of a large number of theoretical studies during the last few years, some information regarding these clusters, such as the influence of temperature, the analysis of their weak interactions, and their Rayleigh scattering properties, is still lacking. In this study, the equilibrium geometric structures and thermodynamics of (CH3)2NH(H2O)n (n = 1–6) clusters were systematically investigated using density functional theory (PW91PW91) coupled with the 6-311++G(3df,3pd) basis set. To determine the most stable isomer and the order of the different isomers, single-point calculations were executed using a two-point extrapolation method in conjunction with the complete basis set for all isomers. The optimized structures show that the addition of a fifth water molecule changes the most stable configuration from a quasi-planar ring structure to a cage-like configuration. Electron density analysis shows that the interactions of these complexes are mainly medium hydrogen bonds. The dependence on temperature of the conformational population and the Gibbs free energies of the (CH3)2NH(H2O)n (n = 1–6) clusters were determined with respect to temperature (200–300 K). A weak dependence on temperature was found for the formation of (CH3)2NH(H2O)n (n = 1–6) clusters. Dimethylamine–water clusters are favorable at low temperatures, but these clusters may be difficult to form because of the combined effect of Gibbs free energies with small negative values and the low relative concentration of dimethylamine in various atmospheric conditions, and this implies that dimethylamine–water clusters are difficult to form spontaneously in the atmosphere. Finally, the Rayleigh scattering properties of (CH3)2NH(H2O)n (n = 1–6) have been investigated systematically for the first time.

In this study we identified Pdc2, the fission yeast ortholog of human Pat1b protein, which forms a complex with Lsm1-7 and plays a role in coupling deadenylation and decapping. The involvement of Pdc2 in RNA degradation and P-body function was also determined. We found that Pdc2 interacts with Dcp2 and is required for decapping in vivo. Although not absolutely essential for P-body assembly, overexpression of Pdc2 enhanced P-body formation even in the absence of Pdc1, the fission yeast functional homolog of human Edc4 protein, indicating that Pdc2 also plays a role in P-body formation. Intriguingly, in the absence of Pdc2, Lsm1 was found to accumulate in the nucleus, suggesting that Pdc2 shuttling between nucleus and cytoplasm plays a role in decreasing the nuclear concentration of Lsm1 to increase Lsm1 in the cytoplasm. Furthermore, unlike other components of P-bodies, the deadenylase Ccr4 did not accumulate in P-bodies in cells growing under favorable conditions and was only recruited to P-bodies after deprivation of glucose in a Pdc2-Lsm1-dependent manner, indicating a function of Pdc2 in cellular response to environmental stress. In supporting this idea, pdc2 mutants are defective in recovery from glucose starvation with a much longer time to re-enter the cell cycle. In keeping with the notion that Pat1 is a nucleocytoplasmic protein, functioning also in the nucleus, we found that Pdc2 physically and genetically interacts with the nuclear 5′–3′ exonuclease Dhp1. A function of Pdc2-Lsm1, in concert with Dhp1, regulating RNA by promoting its decapping/destruction in the nucleus was suggested.