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Summary The rice bean (Vigna umbellata) root apex specifically secretes citrate through expression activation of Vigna umbellata Multidrug and Toxic Compound Extrusion 1 (VuMATE1) under aluminum (Al3+) stress. However, the underlying mechanisms regulating VuMATE1 expression remain unknown. We isolated and characterized a gene encoding Sensitive to Proton Rhizotoxicity1 (STOP1)‐like protein, VuSTOP1, from rice bean. The role of VuSTOP1 in regulating VuMATE1 expression was investigated using the yeast one‐hybrid assay. We characterized the function of VuSTOP1 in Al3 + ‐ and H+‐tolerance using in planta complementation assays. We demonstrated that VuSTOP1 has transactivation potential. We found that VuSTOP1 expression is inducible by Al3+ and H+ stress. However, although VuSTOP1 binds to the promoter of VuMATE1, the inconsistent tissue localization patterns of VuSTOP1 and VuMATE1 preclude VuSTOP1 as the major factor regulating VuMATE1 expression. In addition, when a protein translation inhibitor increased expression of VuSTOP1, VuMATE1 expression was inhibited. In planta complementation assay demonstrated that VuSTOP1 could fully restore expression of genes involved in H+ tolerance, but could only partially restore expression of AtMATE. We conclude that VuSTOP1 plays a major role in H+ tolerance, but only a minor role in Al3+ tolerance. The differential transcriptional regulation of VuSTOP1 and VuMATE1 reveals a complex regulatory system controlling VuMATE1 expression.

In this paper, we propose an electronic nose for non-invasive detection and diagnosis of lung cancer based on a kind of virtual array of surface acoustic wave (SAW) gas sensors and an imaging recognition method. It includes a gas path constructed from a two-bag system, solid phase micro extraction (SPME) and a capillary column to pre-concentrate and separate volatile organic compounds (VOCs) in patients' exhaled air. A pair of SAW sensors, one coated with a thin polyisobutylene (PIB) film, is used to detect chemical compounds. Eleven VOCs that are validated as the markers of lung cancer according to a pathology study can be detected qualitatively and quantitatively by this electronic nose. Then, an improved artificial neural network (ANN) algorithm combined with an imaging method is proposed for the recognition of patients. In addition, the concept of a virtual sensors array based on SAW sensors using a capillary column separation technique and imaging is also proposed to simulate a large scale of sensor array response. Finally this e-nose is calibrated by these 11 VOCs separated in three concentrations and is used to diagnose lung cancer patients in Run Run Shaw hospital. The experimental results show that this kind of electronic nose is effective in the recognition of lung cancer patients.

In this paper, the oil and gas samples produced from tight sandstone reservoir core plugs in immiscible, nearmiscible, and miscible CO 2 flooding processes at the reservoir temperature are experimentally characterized. First, the vanishing interfacial tension (VIT) technique is applied to determine the minimum miscibility pressure (MMP) of the light crude oil−CO 2 system. Second, a total of five CO 2 -coreflood tests are conducted under immiscible, near-miscible, and miscible conditions to thoroughly study the characteristics of the produced oils and gases during each CO 2 flooding process. In the immiscible case (P inj < MMP), the produced oil becomes heavier and heavier during CO 2 injection in terms of its density, viscosity, molecular weight, and hydrocarbons (HCs). The produced gas contains up to 84−96 mol % HCs (dominantly C 4−7 ) extracted from the light crude oil by CO 2 at the beginning and 85−100 mol % CO 2 at the end of CO 2 injection. In the near-miscible case (P inj ≈ MMP), the heaviest oil is produced at 0.4 pore volume (PV) of the injected CO 2 , which is followed by a relatively lighter produced oil from CO 2 breakthrough (BT) at 0.6 PV to the end of CO 2 injection. The produced gas has 40−60 mol % HCs (dominantly C 5−8 ) at the beginning and then consists of almost 100% CO 2 after CO 2 BT. In the miscible case (P inj > MMP), the produced oil becomes much lighter and lighter with the injected PV. The produced gas contains 20−75 mol % HCs (mainly C 5−8 ) at the very beginning and quickly becomes almost 100% CO 2 after CO 2 BT. In summary, this laboratory study provides the comprehensive characterization of the produced fluids in three distinct CO 2 flooding processes. These new experimental data will help to better evaluate the field-scale CO 2 -enhanced oil recovery (EOR) processes and design the future CO 2 -EOR projects as well.

The highly regio- and enantioselective iron-catalyzed anti-Markovnikov hydrosilylation of 1,1-disubstituted aryl alkenes was developed using iminopyridine oxazoline ligands to afford chiral organosilanes. Additional derivatization of these products lead to chiral organosilanols, cyclic silanes, phenol derivatives, and 3-substituted 2,3-dihydrobenzofurans.

Formate dehydrogenase (FDH) is involved in various higher plant abiotic stress responses. Here, we investigated the role of rice bean (Vigna umbellata) VuFDH in Al and low pH (H + ) tolerance. Screening of various potential substrates for the VuFDH protein demonstrated that it functions as a formate dehydrogenase. Quantitative reverse transcription-PCR and histochemical analysis showed that the expression of VuFDH is induced in rice bean root tips by Al or H + stresses. Fluorescence microscopic observation of VuFDH-GFP in transgenic Arabidopsis plants indicated that VuFDH is localized in the mitochondria. Accumulation of formate is induced by Al and H + stress in rice bean root tips, and exogenous application of formate increases internal formate content that results in the inhibition of root elongation and induction of VuFDH expression, suggesting that formate accumulation is involved in both H + -and Al-induced root growth inhibition. Over-expression of VuFDH in tobacco (Nicotiana tabacum) results in decreased sensitivity to Al and H + stress due to less production of formate in the transgenic tobacco lines under Al and H + stresses. Moreover, NtMATE and NtALS3 expression showed no changes versus wild type in these over-expression lines, suggesting that herein known Al-resistant mechanisms are not involved. Thus, the increased Al tolerance of VuFDH over-expression lines is likely attributable to their decreased Al-induced formate production. Taken together, our findings advance understanding of higher plant Al toxicity mechanisms, and suggest a possible new route toward the improvement of plant performance in acidic soils, where Al toxicity and H + stress coexist.

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NaCl ceramics were prepared by room‐temperature cold sintering using moistened NaCl powder with 4 wt% water and dry pressing using dehydrated powder. When the applied uniaxial pressure is low, the relative density of dry‐pressed NaCl ceramic is significantly lower than that of cold‐sintered ceramic, while the former is 98.5%‐99.3% and much higher than the latter (94.3%‐94.6%) for high applied pressure of 200‐300 MPa. The uniaxial pressure‐induced plastic deformation dominates the densification of dry‐pressed NaCl ceramic, and also plays a role during cold sintering as well as the dissolution‐precipitation process. The lower density of cold‐sintered NaCl ceramic under high applied pressure is attributed to the trapped water in ceramic body during cold sintering. Besides, the presence of water always promotes the microstructural homogeneity, which is responsible for the much higher Qf value of cold‐sintered NaCl ceramic. The optimal microwave dielectric properties with εr = 5.55, Qf = 49 600 GHz, and τf = −173 ppm/°C are obtained in cold‐sintered NaCl ceramic under the applied pressure of 300 MPa, indicating that it is a promising candidate as a microwave dielectric material.