Compared with nitrogen and argon, helium is lighter and can better reduce the beam loss caused by angular scattering during beam transmission. The molecular dissociation cross-section in helium is high and stable at low energies, which makes helium the prevalent stripping gas in low-energy accelerator mass spectrometry (AMS). To study the stripping behavior of 14C ions in helium at low energies, the charge state distributions of carbon ion beams with −1, +1, +2, +3, and +4 charge states were measured at energies of 70–220 keV with a compact 14C-AMS at Guangxi Normal University (GXNU). The experimental data were used to analyze the stripping characteristics of C-He in the energy range of 70–220 keV, and new charge state yields and exchange cross-sections in C-He were obtained at energies of 70–220 keV.

A single-stage accelerator mass spectrometer (GXNU-AMS) developed for radiocarbon and tritium measurements was installed and commissioned at Guangxi Normal University in 2017. After several years of operational and methodological upgrades, its performance has been continuously improved and applied in multidisciplinary fields. Currently, the measurement sensitivity for radiocarbon and tritium is 14C/12C ∼ (3.14 ± 0.05) ×10–15 and 3H/1H ∼ (1.23 ± 0.17)×10–16, respectively, and the measurement accuracy is ∼0.6%, which can meet the measurement requirements in the nuclear, earth, environmental and life science fields. This study presents the performance characteristics of GXNU-AMS and several interesting application studies.

It is generally accepted that high-oleic crops have at least 70% oleate. As compared to their normal-oleic counterparts, oil and food products made from high-oleic peanut have better keeping quality and are much healthier. Therefore, high-oleic peanut is well recognized by processors and consumers. However, owing to the limited availability of high-oleic donors, most present-day high-oleic peanut varietal releases merely have F435 type FAD2 mutations. Through screening of a mutagenized peanut population of 15L46, a high-yielding peanut line with desirable elliptical oblong large seeds, using near infrared model for predicting oleate content in individual single seeds, high-oleic peanut mutants were identified. Sequencing FAD2A and FAD2B of the mutants along with the wild type revealed that these mutants possessed G448A FAD2A (F435 type FAD2A mutation) and G558A FAD2B (non-F435 type FAD2B mutation). Expression of the wild and mutated type FAD2B in yeast verified that the functional mutation contributed to the high-oleic phenotype in these mutants. The mutants provided additional high-oleic donors to peanut quality improvement.

Iodine is an important element in thyroid hormone biosynthesis. Thyroid function is regulated by the hypothalamic–pituitary–thyroid axis. Excessive iodine leads to elevated thyroid-stimulating hormone (TSH) levels, but the mechanism is not yet clear. Type 2 deiodinase (Dio2) is a Se-containing protease that plays a vital role in thyroid function. The purpose of this study was to explore the role of hypothalamus Dio2 in regulating TSH increase caused by excessive iodine and to determine the effects of iodine excess on thyrotropin-releasing hormone (TRH) levels. Male Wistar rats were randomised into five groups and administered different iodine dosages (folds of physiological dose): normal iodine, 3-fold iodine, 6-fold iodine, 10-fold iodine and 50-fold iodine. Rats were euthanised at 4, 8, 12 or 24 weeks after iodine administration. Serum TRH, TSH, total thyroxine (TT4) and total triiodothyronine (TT3) were determined. Hypothalamus tissues were frozen and sectioned to evaluate the expression of Dio2, Dio2 activity and monocarboxylate transporter 8 (MCT8). Prolonged high iodine intake significantly increased TSH expression (P < 0·05) but did not affect TT3 and TT4 levels. Prolonged high iodine intake decreased serum TRH levels in the hypothalamus (P < 0·05). Dio2 expression and activity in the hypothalamus exhibited an increasing trend compared at each time point with increasing iodine intake (P < 0·05). Hypothalamic MCT8 expression was increased in rats with prolonged high iodine intake (P < 0·05). These results indicate that iodine excess affects the levels of Dio2, TRH and MCT8 in the hypothalamus.

GBF1 [Golgi brefeldin A (BFA) resistance factor 1] is a member of the guanine nucleotide exchange factors Arf family. GBF1 localizes at the cis-Golgi and endoplasmic reticulum (ER)-Golgi intermediate compartment where it participates in ER-Golgi traffic by assisting in the recruitment of the coat protein COPI. However, the roles of GBF1 in oocyte meiotic maturation are still unknown. In the present study, we investigated the regulatory functions of GBF1 in mouse oocyte organelle dynamics. In our results, GBF1 was stably expressed during oocyte maturation, and GBF1 localized at the spindle periphery during metaphase I. Inhibiting GBF1 activity led to aberrant accumulation of the Golgi apparatus around the spindle. This may be due to the effects of GBF1 on the localization of GM130, as GBF1 co-localized with GM130 and inhibiting GBF1 induced condensation of GM130. Moreover, the loss of GBF1 activity affected the ER distribution and induced ER stress, as shown by increased GRP78 expression. Mitochondrial localization and functions were affected, as the mitochondrial membrane potential was altered. Taken together, these results suggest that GBF1 has wide-ranging effects on the distribution and functions of Golgi apparatus, ER, and mitochondria as well as normal polar body formation in mouse oocytes.

Thermal conductivity behaviors are one of the most important evaluations of carbon fiber-reinforced carbon matrix (C/C) composites in the field of thermal protective structures. In order to deepen the understanding of the thermal conductivity behaviors of C/C composites, the out-of-plane thermal conductivity of C/C composites is studied by considering voids and the fiber volume fractions. The representative volume element (RVE) models of microscale and mesoscale are proposed. The parameters of the RVE models are captured by X-ray micro-computed tomography. The carbon matrix equivalent models and fiber volume fraction models along the z-direction were established. The effects of the porosity and fiber volume fraction along the z-direction on the thermal conductivity were analyzed. The proposed model was validated by experimental results at room temperature. Further, the numerical methods developed in this study can provide guidance for predicting the thermal conductivity of C/C composites with complex structures.

The various vision-based tactile sensors have been developed for robotic perception in recent years. In this paper, the novel soft robotic finger embedded with the visual sensor is proposed for perception. It consists of a colored soft inner chamber, an outer structure, and an endoscope camera. The bending perception algorithm based on image preprocessing and deep learning is proposed. The boundary of color regions and the position of marker dots are extracted from the inner chamber image and label image, respectively. Then the convolutional neural network with multi-task learning is trained to obtain bending states of the finger. Finally, the experiments are implemented to verify the effectiveness of the proposed method.

The micro-nano rough structure promotes the formation of superhydrophobic surfaces, while the formation of superoleophobic surfaces requires the support of re-entrant structures. Electrochemical etching and boiling water treatment methods were used to process the superoleophobic surface in the Al–Mg alloy substrate. The differences between the potential of the aluminum and the magnesium promoted the formation of the surface microstructure under the current stimulation, and the surface was formed into dense nanoscale needle-like coating after boiling water treatment. Scanning electron microscopy, energy dispersive spectroscopy, and contact angle measurement were performed to characterize the morphological features, chemical composition, and surface wettability, respectively. The so-prepared superoleophobic surfaces showed high contact angles and small sliding angles for water, ethylene glycol, and hexadecane. In addition, surface topography, reaction mechanism, and experimental parameters were also studied.

Sterol regulatory element binding protein 1 (SREBP1) has a central regulatory effect on milk fat synthesis. Lipopolysaccharides (LPS) can induce mastitis and cause milk fat depression in cows. SREBP1 is also known to be associated with inflammatory regulation. Thus, in the current study, we hypothesized that LPS-induced milk fat depression in dairy cow mammary epithelial cells (DCMECs) operates via decreased SREBP1 expression and activity. To examine the hypothesis, DCMECs were isolated and purified from dairy cow mammary tissue and treated with LPS (10 µg/ml). LPS treatment of DCMECs suppressed lipid-metabolism-related transcription factor SREBP1 mRNA expression, nuclear translocation and protein expression, leading to reduced triglyceride content. The transcription levels of acetyl-CoA carboxylase-1 and fatty acid synthetase were significantly down-regulated in DCMECs after LPS treatment, suggesting that acetyl-CoA carboxylase-1 and fatty acid synthetase involved in de novo milk fat synthesis was regulated by SREBP1. In summary, these results suggest that LPS induces milk fat depression in dairy cow mammary epithelial cells via decreased expression of SREBP1 in a time-dependent manner.

Porous carbon derived from biomass materials with enrich, low cost, clean, and renewable merits, exhibits various physical and chemical properties. So, it is of great significance to rationally utilize biomass materials for producing porous carbon with low cost to reduce overusing fossil fuel and environmental pollution. In this report, porous carbon has been fabricated using fruits shells of the Paulownia tomentosa by a facile method of KOH-activation. The as-obtained porous carbon containing a larger number of micropores and slight mesopores possesses a high specific surface area (1914.4 m2/g) and well hierarchical porosity. As the anode for sodium ion batteries, the porous carbon sample displays superior cycling stability and rate capability, delivering a reversible specific capacity of 179 mA h/g at 50 mA/g after 100 cycles and a discharge specific capacity of 100 mA h/g at 1 A/g.

Spark plasma sintering (SPS) is adopted to fabricate transparent AlON ceramics at 1350–1500 °C under 40 MPa, using a bimodal γ-AlON powder synthesized by the carbothermal reduction and nitridation method. After holding 10 min, high density samples are obtained, and their optical transmittance is investigated over the wavelength range of 1330–6000 nm. Despite the samples SPS-processed at 1350 °C indicate the presence of three-phases: γ-AlON, α-Al2O3, and h-AlN, they show high infrared transparency, i.e., the maximum transmittance for 1.2 mm thick specimens is up to 77.3% at ∼3900 nm. Also, the processed samples exhibit high hardness of 17.81 GPa. The high infrared transmittance should be mainly attributed to high density and rationally controlled grain size distribution, and the high hardness is apparently caused by a small grain size.

X-ray powder diffraction data, unit-cell parameters, and space group for drospirenone, C24H30O3, are reported [a = 12.897(1) Å, b = 12.618(1) Å, c = 12.252(1) Å, α = β = γ = 90°, unit-cell volume V = 1994.13 Å3, Z = 4, ρcal = 1.229 g cm−3, and space group P212121]. All measured lines were indexed and are consistent with the P212121 space group. No detectable impurities were observed.

We apply the multiscale basis functions for the singularly perturbed reaction-diffusion problem on adaptively graded meshes, which can provide a good balance between the numerical accuracy and computational cost. The multiscale space is built through standard finite element basis functions enriched with multiscale basis functions. The multiscale basis functions have abilities to capture originally perturbed information in the local problem, as a result our method is capable of reducing the boundary layer errors remarkably on graded meshes, where the layer-adapted meshes are generated by a given parameter. Through numerical experiments we demonstrate that the multiscale method can acquire second order convergence in the L2 norm and first order convergence in the energy norm on graded meshes, which is independent of ɛ. In contrast with the conventional methods, our method is much more accurate and effective.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.