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Key Clinical Message Maternally inherited diabetes and deafness (MIDD) is often caused by the m.3243A > G mutation in mitochondrial DNA. Unfortunately, the characteristics of MIDD, especially long‐term outcomes and heteroplasmic changes, have not been well described previously. The purpose of this study was to describe the clinical and genetic features of a family with MIDD after 10 years of follow‐up.A 33‐year‐old male patient with typical characteristics of MIDD, including early‐onset diabetes, deafness, and low body mass index, was admitted to our department. Further investigation revealed that the vast majority of his maternal relatives suffered from diabetes with or without deafness. A detailed family history was then requested from the patient and a pedigree was constructed. The patient suspected of MIDD was screened for mutations using whole mitochondrial DNA sequencing. Candidate pathogenic variants were then validated in other family members through Sanger sequencing. The patient was diagnosed with MIDD, with inherited m.3243A > G mutation in the mitochondrially encoded tRNA leucine 1 (MT‐TL1) gene, after 10 years of symptom onset. The patient was then treated with insulin and coenzyme Q10 to improve mitochondrial function. During the follow‐up period, his fasting blood glucose and HbA1c levels were improved and the incidence of diabetic ketoacidosis was significantly reduced. Our findings indicate that whole mitochondrial DNA sequencing should be considered for patients suspected of MIDD to improve the efficiency of diagnosis and prognosis.

Simulations of 108 emission reduction scenarios for NOx and VOCs using Comprehensive Air Quality Model with Extensions (CAMx) were conducted for eight cities in the Chengdu metropolitan area (CMA). The isopleth diagrams were drawn to explore the responses and differences of ozone (O3) concentrations to NOx and VOCs emission changes under Chengdu, CMA and Sichuan Province emission reduction scenarios. The results show that the O3-sensitive regimes of eight cities may change under different emission reduction scenarios. Under Chengdu emission reduction scenario, the Chengdu city is in the transition regime and O3 formation will shift from transition to VOC-limited when the VOCs emissions decreased by 50%, and the decreases in O3 concentrations caused by VOCs emission reductions are small. For the CMA and Sichuan Province emission reduction scenarios, all cities are NOx-limited in the baseline cases and with at least a 66% and a 77% reduction in NOx emissions, respectively, the daily maximum 8-h average O3 (MDA8) can attain the O3 standard (160 μg m−3). Although reductions in VOCs emissions can also lessen the O3 concentration, the effectiveness is relatively small. The changes in O3 concentrations under different VOCs to NOx emission reduction ratios indicate that all cities achieve a relatively high O3 concentration decrement with low VOCs to NOx emission reduction ratios and that the decreasing O3 concentrations caused by non-local emission reductions are much higher than those achieved by local emission reductions. In addition, the decreases in O3 concentrations in Chengdu are quite close when the total NOx and VOCs emissions reduction percentages are less than 30% under the CMA and Sichuan emission reduction scenarios.

Abstract Background Biogenic volatile organic compounds (BVOCs) play an essential role in tropospheric atmospheric chemical reactions. There are few studies conducted on BVOCs emission of dominant forest species in the Jing-Jin-Ji area of China. Based on the field survey, forest resources data and the measured standard emission factors, the Guenther model developed in 1993 (G93) was applied in this paper to estimate the emission of BVOCs from several dominant forest species (Platycladus orientalis, Quercus variabilis, Betula platyphylla, Populus tomentosa, Pinus tabuliformis, Robinia pseudoacacia, Ulmus pumila, Salix babylonica and Larix gmelinii) in the Jing-Jin-Ji area in 2017. Then the spatiotemporal emission characteristics and atmospheric chemical reactivity of these species were extensively evaluated. Results The results showed that the total annual BVOCs emission was estimated to be 70.8 Gg C·year− 1, consisting 40.5 % (28.7 Gg C·year− 1) of isoprene, 36.0 % (25.5 Gg C·year− 1) of monoterpenes and 23.4 % (16.6 Gg C·year− 1) of other VOCs. The emissions from Platycladus orientalis, Quercus variabilis, Populus tomentosa and Pinus tabulaeformis contributed 56.1 %, 41.2 %, 36.0 % and 31.1 %, respectively. The total BVOCs emission from the Jing-Jin-Ji area accounted for 61.9 % and 1.8 % in summer and winter, respectively. Up to 28.8 % of emission was detected from Chengde followed by Beijing with 24.9 %, that mainly distributed in the Taihang Mountains and the Yanshan Mountains. Additionally, the Robinia pseudoacacia, Populus tomentosa, Quercus variabilis, and Pinus tabulaeformis contributed mainly to BVOCs reaction activity. Conclusions The BVOCs emission peaked in summer (June, July, and August) and bottomed out in winter (December, January, and February). Chengde contributed the most, followed by Beijing. Platycladus orientalis, Quercus variabilis, Populus tomentosa, Pinus tabulaeformis and Robinia pseudoacacia represent the primary contributors to BVOCs emission and atmospheric reactivity, hence the planting of these species should be reduced.

Aiming at the various special circumstances of automobile driving process, a main-auxiliary structure metal spring wheel is proposed, which prevents effectively the abrupt accident caused by blown or punctured tire. Its working principle is described in detail. Besides, the simplified mechanical models of the wheel, the main and auxiliary spring are established. The radial stiffness FEM models of main and auxiliary spring are established. The radial deformation and contact pressure of the wheel are analyzed when the maximum deformation of main spring is 6.22 mm. The radial stiffness curve of a single auxiliary spring is obtained. The relationship among the radial force, the radial deformation, the grounded angle and the grounded circles of auxiliary spring is deduced combining the deformation and stress characteristics of the spring mesh. Finally, the reliability of the mechanical and simulation models is verified by the radial stiffness test. Keywords: Main-auxiliary spring structure wheel, Radial stiffness, Simplified mechanical model, ABAQUS simulation, Wheel test

The hydro-swelling of smectite clay minerals in low-permeability reservoirs further decreases the reservoir permeability and results in low oil recovery. Currently, the traditional chemical anti-swelling agents are widely used, but most of them are only effective in the short term and are not environmentally friendly. Here, we report the use of Fe(III) reducing microorganisms (FeRM) as a novel green anti-swelling agent to enhance oil recovery from low-permeability reservoirs. The results showed that FeRM (Proteus hauserifective) inhibited/reduced the hydro-swelling of smectite clay minerals through a three-step biochemical mineralization reaction process. The structural Fe(III) reduction in minerals by FeRM can be an important driving force for illitization. The maximum inhibition efficiency (36.6%) and shrinkage efficiency (69.3%) were achieved at 35 °C and 0.1 Mpa. Furthermore, core displacement tests showed that FeRM reduced the waterflooding injection pressure by 61.1%, increased the core permeability by 49.6%, and increased the oil recovery by 8.1%. Finally, the mechanism of FeRM-enhanced oil recovery was revealed. This study demonstrates that using FeRM to inhibit/reduce the hydro-swelling of clay minerals holds great potential to enhance the oil recovery from low-permeability reservoirs.

The stable and efficient operation of the activated sludge sequencing batch reactor (ASSBR) in heavy oil refineries has become an urgent necessity in wastewater biotreatment. Hence, we constructed a green and efficient solid bioaugmentation agent (SBA) to enhance the resistance of the reactor to loading shock. The impact of bioaugmentation on the performance and microbial community dynamics under three patterns of heavy oil refinery wastewater (HORW) loading shock (higher COD, higher toxicity, and higher flow rate) was investigated on an industrial-scale ASSBR. Results showed that the optimal SBA formulation was a ratio and addition of mixed bacteria Bacillus subtillis and Brucella sp., of 3:1 and 3.0%, respectively, and a glucose concentration of 5.0 mg/L. The shock resistance of ASSBR was gradually enhanced and normal performance was restored within 6–7 days by the addition of 0.2% SBA. Additionally, the removal efficiency of chemical oxygen demand and total nitrogen reached 86% and 55%, respectively. Furthermore, we found that Burkholderiaceae (12.9%) was replaced by Pseudomonadaceae (17.1%) in wastewater, and Lachnospiraceae (25.4%) in activated sludge was replaced by Prevotellaceae (35.3%), indicating that the impact of different shocks effectively accelerated the evolution of microbial communities and formed their own unique dominant bacterial families.

The selective leaching of zinc from three different basic oxygen steelmaking (BOS) filter cakes by butyric acid was investigated to compare the leaching behaviors of zinc and further to establish the correlation of the zinc leaching performances and the chemical compositions. The effects of acid concentration and the acid to solid (L/S) stoichiometric ratio were studied, with different optimal leaching conditions obtained. BOS-1 showed the lowest leachability with only less than 10% of zinc removed by 0.5 M acid concentration and 90% of the L/S stoichiometric ratio in 10 h. The best zinc selectivity was achieved with BOS-2 at 51.2% of zinc leaching efficiency, with only 0.47% of iron loss under optimal conditions of 1.5 M acid concentration and a 70% stoichiometric ratio. BOS-3 showed the highest leaching of zinc but the optimal conditions depend on the priority consideration. Using 1.0 M acid and 90% stoichiometric ratio for 10 h, the leaching efficiency of zinc was 84.6% with 20% iron loss. The filter cakes and the leaching residues were characterized. The results indicate different zinc and iron leaching behaviors, which were probably related to the storage conditions, zinc containing phases and the leaching parameters.

Biosurfactant producers are crucial for incremental oil production in microbial enhanced oil recovery (MEOR) processes. The isolation of biosurfactant-producing bacteria from oil reservoirs is important because they are considered suitable for the extreme conditions of the reservoir. In this work, a novel biosurfactant-producing strain Acinetobacter junii BD was isolated from a reservoir to reduce surface tension and emulsify crude oil. The biosurfactants produced by the strain were purified and then identified via electrospray ionization-Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR-MS). The biosurfactants generated by the strain were concluded to be rhamnolipids, the dominant rhamnolipids were C26H48O9, C28H52O9 and C32H58O13. The optimal carbon source and nitrogen source for biomass and biosurfactant production were NaNO3 and soybean oil. The results showed that the content of acid components increased with the progress of crude oil biodegradation. A glass micromodel test demonstrated that the strain significantly increased oil recovery through interfacial tension reduction, wettability alteration and the mobility of microorganisms. In summary, the findings of this study indicate that the newly developed BD strain and its metabolites have great potential in MEOR.

In this paper, physical experiments and numerical simulations were applied to systematically investigate the non-Newtonian flow characteristics of heavy oil in porous media. Rheological experiments were carried out to determine the rheology of heavy oil. Threshold pressure gradient (TPG) measurement experiments performed by a new micro-flow method and flow experiments were conducted to study the effect of viscosity, permeability and mobility on the flow characteristics of heavy oil. An in-house developed novel simulator considering the non-Newtonian flow was designed based on the experimental investigations. The results from the physical experiments indicated that heavy oil was a Bingham fluid with non-Newtonian flow characteristics, and its viscosity-temperature relationship conformed to the Arrhenius equation. Its viscosity decreased with an increase in temperature and a decrease in asphaltene content. The TPG measurement experiments was impacted by the flow rate, and its critical flow rate was 0.003 mL/min. The TPG decreased as the viscosity decreased or the permeability increased and had a power-law relationship with mobility. In addition, the critical viscosity had a range of 42–54 mPa∙s, above which the TPG existed for a given permeability. The validation of the designed simulator was positive and acceptable when compared to the simulation results run in ECLIPSE V2013.1 and Computer Modelling Group (CMG) V2012 software as well as when compared to the results obtained during physical experiments. The difference between 0.0005 and 0.0750 MPa/m in the TPG showed a decrease of 11.55% in the oil recovery based on the simulation results, which demonstrated the largely adverse impact the TPG had on heavy oil production.