Tree-ring cellulose is a commonly used material for radiocarbon analysis. Extracting cellulose is labor-consuming and several devices that enable batchwise extraction have been developed. However, these devices bear the risk of sample contamination. The present study describes a new device which improves upon two aspects of currently available devices. First, to prevent cross-sample-contamination, we redesigned the drainage module to enable independent removal of chemical waste from each individual sample funnel. Second, we added covers to the sample funnels to reduce the risk of external contamination. Cellulose purity (i.e., holocellulose) was confirmed by Fourier Transform Infrared (FTIR) Spectroscopy. Furthermore, accuracy of the radiocarbon analysis was confirmed by results of 14C-blank samples and samples of known age. In conclusion, while maintaining labor-saving, our modified device significantly reduces the risk of sample contamination during extraction of tree-ring cellulose.

The rate of dissolution of phlogopite in an open system was measured at low temperature and pressure and at pH 3–5. The maximum dissolution rate was achieved by maintaining extremely low ionic concentrations in the solution using a cation-exchange resin (hydrogen form) as a trap for released cations. The resin also served as a source of hydrogen ions and acted as a buffer. The concentrations of ions adsorbed on the resin and remaining in solution were measured, along with surface area and cation-exchange capacity. The amount of phlogopite dissolved after 1010 hr was 67 times that dissolved using a CO2-buffered, closed-system method. During the first hour of the experiment, dissolution was incongruent, but later became congruent from 1 to 1010 hr. From 1 to 200 hr the reaction had linear kinetics. The dissolution rate for the first 200 hr of the reaction was 2.0 × 10−14 mole KMg3AlSi3O10(OH)2/cm2/sec. Since no evidence of parabolic kinetics was found, there is no reason to postulate the formation of a “protective layer.”

Dry ground phlogopite was placed in deionized water saturated with CO2 at room temperature and pressure. The bulk solution was buffered between a pH of 5 and 6 which is close to the pH of natural weathering systems. The conditions simulated a closed system. After 1010 hr, 2.0% of the total K, 0.95% of the Mg, 0.54% of the Si, and 0.74% of the F had been released, indicating that the dissolution was incongruent. Most of the K was released within 3 min, apparently by a rapid surface exchange with hydrogen ion. One-third of the cation-exchange capacity of this phlogopite arises from cations released from the outer surfaces, while two-thirds arises from the release of more deeply seated cations. All cations exhibited decreasing release with time, the slowest being Si. The rate-controlling “factor” in the later stages is related to the release of Si. It is difficult to distinguish linear from parabolic kinetics in the later stages because of the slow rate of dissolution; however, linear kinetics is most likely. If linear kinetics is applicable, the dissolution rate of Si was 3.8 × 10−17 mole/cm2/sec. Conclusions may be affected by the length of the experimental run.

Large-scale outbreaks of the dinoflagellate Karenia mikimotoi caused substantial mortality of abalone, Haliotis discus hannai in Fujian, China in 2012, resulting in 20 billion in economic losses to abalone industries. However, the mechanism behind the mortality, especially the reaction of abalone to this microalgal toxicity, which possibly differed significantly from the former ‘fish killer’ strain in the South China Sea (SCS). Our study revealed that K. mikimotoi FJ-strain exhibited a four-fold higher haemolytic toxicity than the SCS-strain during the late exponential phase. At the microalgal cell density of 3 × 107 cell L−1, the FJ-strain caused abalone mortality of 67% in 48 h, with decreased granulocyte–hyalinocyts ratio and phagocytic activity by 58.96% and 75.64%, respectively, increased haemocyte viability by 4.8-fold and severe gill damage. The toxic effect only worked for the haemolytic toxicity from active algal cells, which were probably produced under the contact of algal cells and abalone gills. However, under exposure to the SCS-strain, more than 80% of individuals survived under aeration. The results indicated that FJ-strain was a new K. mikimotoi ecotype with stronger toxicity. It evoked severe effects, with complete abalone mortality within 24 h under the cascading effect of non-aeration (dissolved oxygen declined to 2.0 mg L−1), when exposed to K. mikimotoi FJ-strain at the above density. Thus, apart from the microalgal toxicity, DO depletion exacerbated the mortality of abalone in the experiment. The massive abalone mortalities in Fujian were probably caused by the combination of microalgal toxic effects and oxygen depletion, leading to immunological depression and histopathological disruption.

The status of the genera Euparagonimus Chen, 1963 and Pagumogonimus Chen, 1963 relative to Paragonimus Braun, 1899 was investigated using DNA sequences from the mitochondrial cytochrome c oxidase subunit I (CO1) gene (partial) and the nuclear ribosomal DNA second internal transcribed spacer (ITS2). In the phylogenetic trees constructed, the genus Pagumogonimus is clearly not monophyletic and therefore not a natural taxon. Indeed, the type species of Pagumogonimus,P. skrjabini from China, is very closely related to Paragonimus miyazakii from Japan. The status of Euparagonimus is less obvious. Euparagonimus cenocopiosus lies distant from other lungflukes included in the analysis. It can be placed as sister to Paragonimus in some analyses and falls within the genus in others. A recently published morphological study placed E. cenocopiosus within the genus Paragonimus and probably this is where it should remain.

The oil sands of western Canada represent the third largest hydrocarbon deposit in the world. Bitumen, a very heavy petroleum, is recovered from mined oil sands using warm water extraction followed by separation treatments to isolate the bitumen product. The high energy, water use, as well as tailings remediation challenges associated with the warm water extraction process raise major environmental concerns. Non-aqueous extraction using organic solvents at room temperature has been investigated extensively as an alternative to the warm water extraction process. The main challenge to the large-scale implementation of non-aqueous extraction is the retention of solvent in the tailings. The objective of this work was to present and validate a computational model for the interaction of solvents used in non-aqueous extraction with minerals, such as the abundant and adsorbent clay mineral kaolinite. The model system contained a periodically extended kaolinite platelet immersed in a solvent and all were treated at the atomic level using the 3D Reference Interaction Site Model with the Kovalenko-Hirata closure approximation (3D-RISM-KH) molecular theory of solvation. The solvent solvation free energy of interaction with kaolinite as well as site-specific adsorption energies and kinetic barriers for desorption were computed based on the solvent site density distribution functions. Moreover, the lateral and integrated density distributions were computed to analyze the organization of solvent at kaolinite surfaces. The integrated density distribution profiles were correlated with experimental adsorption isotherms. The results showed very strong adsorption of ethanol and weak adsorption of hydrocarbon solvents on kaolinite, which were in qualitative agreement with experimental solvent extraction reports. The model and these findings are valuable in understanding the mechanism of solvent retention in tailings after non-aqueous extraction and highlight the action of hydroxylated cosolvent additives to enhance extraction using nonpolar solvents.

We explored the transmission mechanisms of corporate fraud and its punishments within social network communities. Using fraud triangle theory and trust triangle theory, we hypothesize four transmitting channels of how fraud commission and detection are affected by peers’ fraud and punishment. Based on Chinese listed corporations from 2008 to 2018, we first construct and detect interlocked social network communities with a community-detecting algorithm, and then examine hypotheses using a bivariate probit model with partial observability. Our findings indicate that peer-concealing and -hinting effects exist within social network communities. The peer-concealing effect decreases the likelihood of being detected when committing fraud, for those with more and closer fraudulent peers. The peer-hinting effect increases the likelihood of being detected when committing fraud, for those with more and closer punished peers. There is no evidence to support peer-contagion and vicarious-punishment effects. Thus, an improved understanding of the transmission mechanism of corporate fraud commission and detection within communities is provided to prevent and detect corporate fraud. In addition, stakeholders and regulators should be aware of the deviant subculture and social distancing in social network communities.

Straightplasma channels are widely used to guide relativistic intense laser pulses over several Rayleigh lengths for laser wakefield acceleration. Recently, a curved plasma channel with gradually varied curvature was suggested to guide a fresh intense laser pulse and merge it into a straight channel for staged wakefield acceleration [Phys. Rev. Lett. 120, 154801 (2018)]. In this work, we report the generation of such a curved plasma channel from a discharged capillary. Both longitudinal and transverse density distributions of the plasma inside the channel were diagnosed by analyzing the discharging spectroscopy. Effects of the gas-filling mode, back pressure and discharging voltage on the plasma density distribution inside the specially designed capillary are studied. Experiments show that a longitudinally uniform and transversely parabolic plasma channel with a maximum channel depth of 47.5 μm and length of 3 cm can be produced, which is temporally stable enough for laser guiding. Using such a plasma channel, a laser pulse with duration of 30 fs has been successfully guided along the channel with the propagation direction bent by 10.4°.

People's willingness to forgive corrupt government officials has intrigued many researchers. According to a prominent explanation, citizens tolerate corrupt officials in exchange for their ability to deliver public benefits, such as promoting economic development. We contextualize this corruption–competence tradeoff thesis by assessing individuals' evaluations of local officials in China. We conduct a nationwide vignette experiment with 5527 citizens, and find that the corruption–competence tradeoff exists and is hierarchical. Respondents prefer competent but corrupt low-level officials over those who are honest but incompetent, but this relative preference vanishes when they evaluate high-level local officials. Our interviews reveal that proximity to citizens and position in the power hierarchy primarily drive citizens' sophisticated assessments of officials at different levels.

The phase summation effect in sum-frequency mixing process is utilized to avoid a nonlinearity obstacle in the power scaling of single-frequency visible or ultraviolet lasers. Two single-frequency fundamental lasers are spectrally broadened by phase modulation to suppress stimulated Brillouin scattering in fiber amplifier and achieve higher power. After sum-frequency mixing in a nonlinear optical crystal, the upconverted laser returns to single frequency due to phase summation, when the phase modulations on two fundamental lasers have a similar amplitude but opposite sign. The method was experimentally proved in a Raman fiber amplifier-based laser system, which generated a power-scalable sideband-free single-frequency 590 nm laser. The proposal manifests the importance of phase operation in wave-mixing processes for precision laser technology.

The study aimed to explore the relationships of skeletal muscle mass with disease severity in metabolic-associated fatty liver disease (MAFLD) patients with different methods. Consecutive subjects undergoing bioelectrical impedance analysis were included. The steatosis grade and liver fibrosis were evaluated by MRI-derived proton density fat fraction and two-dimensional shear wave elastography. The appendicular skeletal muscle mass (ASM) was adjusted by height2 (ASM/H2), weight (ASM/W) and BMI (ASM/BMI). Overall, 2223 subjects (50·5 %, MAFLD; 46·9 %, male) were included, with the mean age 37·4 ± 10·6 years. In multivariate logistic regression analysis, the subjects with the lowest quartile (Q1) of ASM/W or ASM/BMI had higher risk ratios for MAFLD (OR (95 % CI) in male: 2·57 (1·35, 4·89), 2·11(1·22, 3·64); in female: 4·85 (2·33, 10·01), 4·81 (2·52, 9·16), all P < 0·05, all for Q1 v. Q4). The MAFLD patients with lower quartiles of ASM/W had the higher risk OR for insulin resistance (IR), both in male and female (2·14 (1·16, 3·97), 4·26 (1·29, 14·02) for Q4 v. Q1, both P < 0·05). While the significant OR were not observed when ASM/H2 and ASM/BMI were used. There were significant dose-dependent associations between decreased ASM/W as well as ASM/BMI and moderate–severe steatosis (2·85(1·54, 5·29), 1·90(1·09, 3·31), both P < 0·05) in male MAFLD patients. In conclusion, ASM/W is superior to ASM/H2 and ASM/BMI in predicting the degree of MAFLD. A lower ASM/W is associated with IR and moderate–severe steatosis in non-elderly male MAFLD.