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• We conducted a research based on a new angiographic classification. • The success rate of interventional surgery is related to the morphology of stump. • Endovascular recanalization may be safe, effective, and feasible for VOO patients. Non-acute vertebral ostial occlusion (VOO) is a debilitating condition with significant mortality and morbidity rates. However, currently, there is no consensus on the optimal treatment strategy for VOO. This study aims to examine the feasibility, effectiveness, and safety of endovascular recanalization in patients with VOO. We conducted a retrospective review of data from 21 consecutive patients with VOO who underwent endovascular recanalization between May 2018 and August 2023. The patients were divided into two groups based on a new angiographic classification proposed by Gao et al. Type I (tapered stump group) included patients with non-acute extracranial vertebral artery ostial occlusion presenting a tapered occlusion stump. Type II (nontapered stump group) consisted of patients with a nontapered occlusion stump. We collected data on recanalization rates, perioperative complications, and follow-up outcomes. Our analysis included data from a total of 21 patients (22 lesions) with a mean age of 64.6 ± 10.6 years. The technical success rate was 66.7 % (14/21), and the rate of periprocedural complications was 14.3 % (3/21). The success rate of transitioning from the tapered stump group to the nontapered stump group was 90.9 % (10/11) and 40 % (4/10), respectively (P = 0.024). The perioperative complication rate for type I and type II patients was 18.2 % (2/11) and 10 % (1/10), respectively. Among these patients, 18 cases underwent endovascular recanalization using transfemoral access, while 3 patients underwent transradial access after failed transfemoral access, with successful outcomes for two patients. This study suggests that endovascular recanalization may offer a safe, effective, and feasible treatment option for VOO patients. Additionally, the proposed angiographic classification may serve as a useful guide in selecting suitable candidates for surgery. [ABSTRACT FROM AUTHOR]

• CFD simulations clarified the gas atomization process for FeCoNiCrMoBSi HEA. • Experimentally observed, the size distribution of gas-atomized HEA powder concentrates in the 30∼40 μm range, aligning with numerical simulations. • The FCC structure and eutectic microstructural characteristics are observed in the gas-atomized FeCoNiCrMoBSi HEA powder. • The estimated cooling rate of secondary droplets ranges from 1.22 × 104 K/s to 2.64 × 105 K/s. The intricate processes governing the gas atomization of molten metal droplets and their subsequent solidification hold paramount significance in materials science. Computational fluid dynamics simulations have emerged as indispensable tools for unraveling the complexities inherent in metal melt atomization. This study employed the volume of fluid method and the shear-stress transport k-ω turbulence model to simulate the primary atomization process of a FeCoNiCrMoBSi high-entropy alloy. Subsequently, the discrete phase model and Taylor analogy breakup model, based on the gas Weber number and incorporating primary atomization outcomes as initial conditions, were utilized to simulate droplet formation during the secondary atomization process. Analysis of the particle size distribution at the outlet of the geometric model demonstrated excellent agreement with experimental data for gas-atomized FeCoNiCrMoBSi high-entropy alloy powder. Furthermore, comprehensive characterization analyses were conducted to probe the phase constitution and structure of FeCoNiCrMoBSi powder produced by gas atomization. The results revealed that, irrespective of particle size, the powder exhibited a face-centered cubic structure and distinctive eutectic microstructural characteristics. The numerical simulation provided insights into the solidification process of secondary droplets by integrating inverse pole figure data for gas-atomized powder across varying particle sizes. The estimated cooling rate of secondary droplets ranged from 1.22 × 104 K/s to 2.64 × 105 K/s. These findings significantly advance the understanding of the gas atomization mechanism of the FeCoNiCrMoBSi high-entropy alloy, paving the way for the development of more efficient manufacturing processes for advanced materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Crude oil plays a vital role in industrial and social development and has become an integral part of the economic development. However, influenced by policies, wars, etc., it is hard to capture the trend of complex and volatile crude oil price if only one model is used, which often leads to poor forecasts. To enhance the prediction accuracy and robustness of forecasting models, a novel combined forecasting method with time-varying weights, i.e., Jaynes weight hybrid (JWH) model incorporating the Shannon information entropy and several forecasting methods is proposed in this paper. In the selection of the baseline models, the autoregressive integrated moving average in classical statistical forecasting strategies, back propagation neural network, extreme learning machine in neural network and long short-term memory neural network in deep learning models are chosen to fit the crude oil price. Four datasets and three experiments are constructed to verify the prediction ability of the novel combined forecasting model. Empirical results are calculated by five measurement criteria, suggesting that the prediction accuracy of the novel combined method is significantly higher than several comparison models and the mean absolute percentage error of the model has arrived 2.81 % in detail. Particularly, the proposed model has achieved satisfactory performances in Covid-19 and the War in Ukraine, further verifying the robustness of the combined methodology. • A time-varying weight combined forecasting model is proposed for crude oil price. • The proposed model outperforms the comparison models. • The proposed model shows good robustness during special period: COVID-19. • Hypothesis testing is used to test the validity of the proposed combination model. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Simulations of formation pressure based on different hypotheses are applied to determine reservoir connectivity of Z21 field. • Distributions of formation pressure in the west zone of Z21 field are largely affected by a low-permeability belt. • Reservoir connectivity between the west and main zone is proved weak due to the existence of the low-permeability belt. Abstract The Z21 gas field is the only one gas field in the Huizhou depression. The distributions of sandstone and mudstone in the adjacent west zone control the extent of the Z21 gas field, making the confirmation of the reservoir connectivity between the west zone and main zone (RCWM) crucial. In this study, a practical workflow was proposed to confirm the RCWM. First, the sandstone and mudstone distributions were modeled by a sequential indicator simulation, using the vertical proportion curves as constraints. The porosity and permeability distributions were then predicted using a sequential Gaussian simulation based on sandstone and mudstone models. The sandstone, mudstone, and physical property models were treated as components of a geological embryonic model (GEM) prior to the RCWM confirmation. Different hypotheses on the RCWM of the GEMs were drawn, bringing variations to the GEMs and the GEMs turned to be different new models. These new models were then applied to numerical simulations, not only to perform quality checks, but also to attain the simulated formation pressure coefficients (Pfcs) and couple the study with the current formation pressure coefficients (Pfcc) derived from the modular formation dynamics tester (MDT). A hypothesis is negated if the Pfcs is not equal or approximately equal to the Pfcc. A coupled result was iteratively generated until the RCWM was confirmed. This coupling study on reservoir connectivity makes use of general geological reservoir models and highlights the ingenious designs based on different hypotheses of the RCWM to generate reliable results. Coupling study shows that distributions of formation pressure in the west zone of Z21 field are largely affected by a low-permeability belt and RCWM is proved weak due to the existence of the low-permeability belt. [ABSTRACT FROM AUTHOR]

In this study, 78 surface sediment samples were collected from the Weihai coastal area and analyzed for heavy metals. Their concentrations and pollution status were evaluated. The distribution of heavy metals was mainly dominated by sediment grain size, and the sediments in the Weihai, Sanggou, and Rushan Bays, which have finer grain sizes, had higher concentrations. The mean geoaccumulation index values for all heavy metals were <0. Expect for Hg, the mean enrichment factor values of the other metals were <1.5, indicating that they are natural sourced. Overall, the environmental quality of the Weihai costal area was relatively good and should be maintained and protected. The heavy metals that had potential impacts on the ecological environment were Cd and Hg, which were mainly distributed west of Weihai Bay and inside Rushan Bay. They are affected by human activities and must be controlled. • Spatial distributions and pollution status of seven heavy metals were determined. • Except for Cd and Hg in a few stations, most heavy metals were natural sourced. • Heavy metals Cd and Hg had potential impacts on the ecological environment. [ABSTRACT FROM AUTHOR]

In this study, 214 surface sediment samples were collected from the offshore area of the Dongying coast and were analysed for heavy metals; particularly, their concentrations and pollution status were evaluated. The copper (Cu) and chromium (Cr) distributions were similar, their concentrations were the highest in the northeast areas and the Xiaoqing River estuary, where dominated by fine-grained sediments. Higher concentrations of lead (Pb), zinc (Zn), cadmium (Cd), and arsenic (As) were generally found in the offshore area of the study location, and the highest Cd concentration was observed in the Xiaoqing River estuary. The sediments were not polluted by Cu, Pb, Zn, and Cr; they were not polluted or moderately polluted by Cd and As. Results of the principal component analysis indicated that Cu, Pb, Zn, and Cr were derived from natural sources and Cd and As were derived from anthropogenic sources. • Spatial distributions and pollution status of six heavy metals were determined. • Surface sediments were not polluted by Cu, Pb, Zn, and Cr. • Cu, Pb, Zn, and Cr were derived from natural sources. • Geochemical approach confirms anthropogenic influence of Cd and As. [ABSTRACT FROM AUTHOR]

• The restraint history of the concrete wall at the early age was investigated. • A new restraint model for the concrete structure was proposed. • A new calculation method of the thermal stress was proposed. The restraint degree of the early-age concrete structure is an important factor for the generation of the thermal stress. When the concrete cannot deform freely as a result of the restrained deformation, the thermal stress, will generate until it increases to the degree that is great enough to affect the service life and safety of the concrete structure. Therefore, a new prediction method based on the time-restraint is proposed in this study. In the field test, a combination of the strain history of the newly cast concrete wall and the linear logarithmic creep model was adopted to calculate the thermal stresses. Compared with the traditional method, the complex structural restraint development can be described by a restraint model. The restraint coefficient of a specified location in the concrete wall changes from complete restraint to non-complete restraint, which can be transformed into a function of restraint coefficient related to the curing age. Compared with previous restraint evaluations, the restraint model reflects the restraint development of early-age concrete structures more authentically. Combined with the new restraint model, the thermal stress can be estimated with the completely restrained stress. [ABSTRACT FROM AUTHOR]

[Display omitted] • The yield of hexanoic acid increased by 58% with the addition MgCO 3. • Mg2+ and NH 4 + mitigated the excessive ethanol oxidation, while Ca2+ facilitated it. • Batch addition of NaHCO 3 enhanced the synthesis of hexanoic acid. • High CO 2 concentration facilitated the proliferation of Uribacillus and Prevotella. • Clostridium_sensus_stricto_ 12 was the main hexanoic acid-producing bacterium. Carbon dioxide (CO 2) plays a crucial role in carbon chain elongation with ethanol serving as an electron donor. In this study, the impacts of various carbonates on CO 2 concentration, hexanoic acid production, and microbial communities during ethanol-butyric acid fermentation were explored. The results showed that the addition of MgCO 3 provided sustained inorganic carbon and facilitated interspecific electron transfer, thereby increasing hexanoic acid yield by 58%. MgCO 3 and NH 4 HCO 3 inhibited the excessive ethanol oxidation and decreased the yield of acetic acid by 51% and 42%, respectively. The yields of hexanoic acid and acetic acid in the CaCO 3 group increased by 19% and 15%, respectively. The NaHCO 3 group exhibited high headspace CO 2 concentration, promoting acetogenic bacteria enrichment while reducing the abundance of Clostridium_sensu_stricto_ 12. The batch addition of NaHCO 3 accelerated the synthesis of hexanoic acid and increased its production by 26%. The relative abundance of Clostridium_sensus_stricto_ 12 was positively correlated with hexanoic acid production. [ABSTRACT FROM AUTHOR]

Abstract Fan delta systems have long been studied as a kind of good hydrocarbon reservoirs. Although many models have been raised according to their local conditions, there still exists some controversies regarding the formations of the ones developed in continental syn-rift settings. Taking Paleogene Es 3 2+3 of Gaobei Slope Belt as an example, this paper conducted a comprehensive geological study and a forward depositional modeling. The results show that the sediment within the study area came mainly from the northeastern Baigezhuang uplift and the northwestern Xinanzhuang uplift over a short distance. The sedimentary system is characterized by subaerial debris flow, subaerial braided channels, subaqueous distributary channels, front sand bars and front sand sheets. Furthermore, the study area is a balance-filled basin that experienced a 3rd order normal regression followed by a transgression during the development of the study interval. The results also show that, a stable subsidence rate with small-magnitude climate changes would be a plausible explain for the entire sequence of the fan delta system in the study area. The tectonic subsidence was indeed the dominant driving force to a continental syn-rift fan delta system, although the climate, sediment supply or lake level might bring some lower order (e.g., 4th and 5th order) superimpositions. This paper proposed a likely model for fan deltas developed in continental syn-rift settings, which is expected to gain some insights into the forming mechanism and provide some supports for the reservoir characterization of similar and correlative sedimentary systems. Highlights • The sediments within the study area came mainly from the northeastern and the northwestern uplifts over a short distance. • The subsidence of the boundary faults was the main driving force for the creation of accommodation space. • Stable subsidence rate with lower-order climate changes would be a plausible explain for the formation of the fan delta. [ABSTRACT FROM AUTHOR]

• Millennial-scale C3/C4 ecosystem changes in the Pearl River delta plain studied. • Three major C4 grassland expansions/decreases of monsoon rainforest landscape identified inMIS 2. • Changes of plant ecosystems closely tracked rainfall records in southern subtropical China. The impact of abrupt climate change during glacial periods on terrestrial ecosystems are widely acknowledged by paleoecology and paleoclimate communities as key issues in the ongoing debate on geographical distribution and patterns of genetic diversity of species. However, the C 4 plant expansion in subtropical South China at the mouth of the Pearl River during the glaciated Marine Isotope Stage 2 (MIS 2) in response to millennial-scale climate changes is largely unknown. In this study we present results of the isotopic composition of sediment organic carbon (δ13C TOC) obtained from a high-resolution fluvial sequence from the Pearl River delta plain in southern China to show millennial-scale C 3 /C 4 ecosystem changes during the MIS 2 interval. Three major C 4 grassland expansions and declines of the monsoon rainforest landscape are identified during the MIS 2 period. Our results reveal that during MIS 2 δ13C TOC values shifted profoundly from about −29 ‰ to enriched values of up to −17 ‰ three times and we interpret these as due to episodic expansions of the C 4 plants to form a mixed C 3 /C 4 plant ecosystem with the collapse of a pure C 3 monsoon rainforest community in this region. These drastic expansions of C 4 ecological systems occurred at 24.8–24 ka, 23.8–21 ka, and 18–15.6 ka cal BP intervals, equivalent to well-known Heinrich Stadial (HS) 2, Last Glacial Maximum (LGM), and HS1 super-cold Northern Hemisphere intervals. We found that these drastic changes of plant ecosystems closely tracked the monsoon records during the significant weakening of Asian Summer Monsoon Intervals (WSMIs) of the MIS 2 period. [ABSTRACT FROM AUTHOR]

• The theoretical dynamic model of optical measuring volume (OMV) with gas temperature is established. • The application condition of OPC is extended to 650 °C. • An optical measurement method of non-spherical particle based on high temperature melting technique is proposed. Optical particle counter (OPC) is always used to measure particles in high-temperature gas pipelines through gas cooling, leading to the original molten droplets condensing into irregular solid particles. To solve the problem, an optical measurement method of non-spherical particle size and concentration based on high-temperature melting technique is proposed. By establishing the theoretical dynamic model of optical measuring volume (OMV) of commercial OPC (Welas 3000, PALAS GMBH, Germany) with changing gas temperature and studying the thermal expansion characteristics of aerosol conduit, the influence of gas temperature on OPC optical sensor is analyzed, and OPC is applied at 650 °C. On this foundation, irregular glass particles are melted into spherical shape by high-temperature melting technique to realize the optical measurement of particle size and mass concentration. By comparing the online and off-line results of mass concentration, the deviation between them is less than 5%, verifying the feasibility of the proposed method. [ABSTRACT FROM AUTHOR]