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Background: Previous studies have found that the triglyceride glucose index (TyG index) trajectories are associated with cardiovascular diseases. However, the association between the patterns of TyG index trajectories and risk for hypertension has not been investigated. In a longitudinal general population, we aimed to identify distinct TyG index trajectories over 12 years and describe their association with incidence of hypertension. Method: Of the 15,056 adults retrospectively recruited from the Physical Examination Center of the Second Affiliated Hospital of Dalian Medical University in northeast of China from 2011 to 2022. TyG index was calculated as ln (fasting TG [mg/dL] × FPG [mg/dL]/2) and the TyG index trajectories were developed using group-based trajectory modelling. Cox regression analysis was accomplished to assess the association between TyG index and incidence of hypertension. Results: The median age of the population was 38 years, and 7352 (48.83%) of the participants were men. Three distinct TyG index trajectories were identified: "low increasing" (N = 7241), "moderate increasing" (N = 6448), and "high stable" (N = 1367). Using "low increasing" trajectory as a reference, "moderate increasing" and "high stable" trajectory were associated with increased risk of hypertension (HR = 2.45; 95% CI 2.25–2.67 and HR = 3.88; 95% CI 3.48–4.33). After adjusting for baseline sex, age, diabetes, smoking, systolic blood pressure, diastolic blood pressure, BMI, cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, blood glucose, triglyceride, urea, uric acid, and glomerular filtration rate, the HR were slightly attenuate in "moderate increasing" and "high stable" trajectories to 1.38 (95% CI 1.23–1.54) and 1.69 (95% CI 1.40–2.02) respectively. Meanwhile, similar results were observed in multiple sensitivity analyses. The HR of the "moderate increasing" and "high stable" trajectory groups were 2.63 (95% CI 2.30–3.00) and 4.66 (95% CI 3.66–5.93) in female, and 1.66 (95% CI 1.48–1.86) and 2.33 (95% CI 2.04–2.66) in male. Conclusions: Elevated TyG index at baseline and long-term TyG index trajectories were associated with the risk of hypertension. Early identification of increasing TyG index could provide insights for preventing hypertension later in life. [ABSTRACT FROM AUTHOR]

Highly rarefied gas flows through a rough channel of finite length with small bumps appended to its surfaces are investigated, by varying the accommodation coefficient α in Maxwell's diffuse-specular boundary condition, the characteristic size and position of the bumps, and the channel length. First, we study the influence of the surface bumps and consider the rarefied gas flow in a unit channel with periodic boundary conditions to remove the end effect. It is found that the surface bumps have a significant impact on the flow permeability. When α is very small (i.e., nearly specular reflection of gas molecules at the channel surface), the apparent gas permeability is dramatically reduced, even in the presence of small bumps, to a value that is almost comparable to the one when fully diffuse gas-surface scattering is assumed. This impact can be taken into account through an effective accommodation coefficient, i.e., the permeability of the rough channel is taken equivalently as that of a smooth channel without bumps but having gas-surface scattering under the effective accommodation coefficient. Second, we study the end effect by connecting a smooth channel of length L 0 to two huge gas reservoirs. It is found that (i) the end correction length is large at small α . Consequently, the mass flow rate barely reduces with increasing L 0 rather than scales down by a factor of 1 / L 0 as predicted by the classical Knudsen diffusion theory; and (ii) the end correction is related to the channel's aspect ratio. Finally, based on the effective accommodation coefficient and end correction, we explain the exotic flow enhancement in graphene angstrom-scale channels observed by Geim's research group (Keerthi et al, Nature 558:420–424, 2018). [ABSTRACT FROM AUTHOR]

In this work, a facile room-temperature (RT) solution-processing strategy was developed to synthesize perovskite CsPbBr3 quantum dots (QDs), which were then modified with Zn-based organic ligands for enhancing their ambient environment and moisture stability. The as-prepared perovskite QDs were well dispersed in a trimethylbenzene solvent with a small particle size of ∼9 nm. Afterwards, a sensor was fabricated by spin-coating perovskite QDs on an interdigital electrode, leading to a sensitivity of 0.025 towards 400 ppm ethanol gas as well as a response/recovery time of 3.9 s/3.6 s at RT. This excellent sensing performance is attributed to the high carrier mobility and adjustable crystal structure of perovskite CsPbBr3 QDs. Theoretical calculation results verified that the sensitivity towards ethanol might result from the formation of chemical bonds between perovskite QDs and Zn-based ligands, leading to a change of molecular orbital energy levels. Furthermore, with a combination of machine-learning algorithms, accurate recognition of ethanol was realized in an ambient environment with high humidity. Our research might be helpful to construct an intelligent sensor for application under complex conditions, such as coal mines and chemical factories. [ABSTRACT FROM AUTHOR]

A simulation study was carried out to investigate the temporal evolution of H2S in the Huangcaoxia underground gas storage (UGS), which is converted from a depleted sulfur-containing gas field. Based on the rock and fluid properties of the Huangcaoxia gas field, a multilayered model was built. The upper layer Jia-2 contains a high concentration of H2S (27.2 g/m3), and the lower layer Jia-1 contains a low concentration of H2S (14.0 mg/m3). There is also a low-permeability interlayer between Jia-1 and Jia-2. The multi-component fluid characterizations for Jia-1 and Jia-2 were implemented separately using the Peng-Robinson equation of state in order to perform the compositional simulation. The H2S concentration gradually increased in a single cycle and peaked at the end of the production season. The peak H2S concentration in each cycle showed a decreasing trend when the recovery factor (RF) of the gas field was lower than 70%. When the RF was above 70%, the peak H2S concentration increased first and then decreased. A higher reservoir RF, a higher maximum working pressure, and a higher working gas ratio will lead to a higher H2S removal efficiency. Similar to developing multi-layered petroleum fields, the operation of multilayered gas storage can also be divided into multi-layer commingled operation and independent operation for different layers. When the two layers are combined to build the storage, the sweet gas produced from Jia-1 can spontaneously mix with the sour gas produced from Jia-2 within the wellbore, which can significantly reduce the overall H2S concentration in the wellstream. When the working gas volume is set constant, the allocation ratio between the two layers has little effect on the H2S removal. After nine cycles, the produced gas's H2S concentration can be lowered to 20 mg/m3. Our study recommends combining the Jia-2 and Jia-1 layers to build the Huangcaoxia underground gas storage. This plan can quickly reduce the H2S concentration of the produced gas to 20 mg/m3, thus meeting the gas export standards as well as the HSE (Health, Safety, and Environment) requirements in the field. This study helps the engineers understand the H2S removal for sulfur-containing UGS as well as provides technical guidelines for converting other multilayered sour gas fields into underground storage sites. [ABSTRACT FROM AUTHOR]