Middle Stage Research Articles

Metagenomic and metatranscriptomic analyses of microbial genera and volatiles produced during the fermentation of doubanjiang meju

Fermented broad beans (Vicia faba L.), commonly known as meju, serve as a crucial raw material for producing Pixian Doubanjiang (DBJ), a traditional condiment in Chinese cuisine. However, there is limited information on the dynamics of fungal populations and the activity shifts of key enzymes during DBJ meju fermentation. This study aimed to elucidate the microbial composition, active genera, expressed genes and pathways during the DBJ meju fermentation. The general chemical components, free amino acids, enzymes and volatile compounds were also investigated; the correlations between active genera and physicochemical factors were analyzed, at different fermentation stages. The results demonstrated that protease was the predominant enzyme during meju fermentation. A total of 32 major volatile compounds were identified, with most alcohols and aldehydes showing a sharp increase from the early to the middle stages, followed by stabilization until the end of fermentation. Significant shifts in metatranscriptomic composition at the genus level were observed, with Aspergillus, Staphylococcus, and Tulasnella emerging as the core active genera in the process. Notably, cellulase activity was positively correlated with the presence of Tulasnella. Additionally, Aspergillus and Tulasnella were found to play a crucial role in developing the unique aroma of DBJ meju. Our findings on the succession of active genera and their correlation with physicochemical factors are expected to provide substantial evidence for potential quality control and enhancement of this renowned Chinese condiment.

High performance RGB-Thermal Video Object Detection via hybrid fusion with progressive interaction and temporal-modal difference

RGB-Thermal Video Object Detection (RGBT VOD) is to localize and classify the predefined objects in visible and thermal spectrum videos. The key issue in RGBT VOD lies in integrating multi-modal information effectively to improve detection performance. Current multi-modal fusion methods predominantly employ middle fusion strategies, but the inherent modal difference directly influences the effect of multi-modal fusion. Although the early fusion strategy reduces the modality gap in the middle stage of the network, achieving in-depth feature interaction between different modalities remains challenging. In this work, we propose a novel hybrid fusion network called PTMNet, which effectively combines the early fusion strategy with the progressive interaction and the middle fusion strategy with the temporal-modal difference, for high performance RGBT VOD. In particular, we take each modality as a master modality to achieve an early fusion with other modalities as auxiliary information by progressive interaction. Such a design not only alleviates the modality gap but facilitates middle fusion. The temporal-modal difference models temporal information through spatial offsets and utilizes feature erasure between modalities to motivate the network to focus on shared objects in both modalities. The hybrid fusion can achieve high detection accuracy only using three input frames, which makes our PTMNet achieve a high inference speed. Experimental results show that our approach achieves state-of-the-art performance on the VT-VOD50 dataset and also operates at over 70 FPS. The code will be freely released at https://github.com/tzz-ahu for academic purposes.

The evolution of granular surface structure and functional properties in rice starch during grain filling

The developmental changes in the granular surface structure and functional properties of starch during the entire grain filling period of rice (around 40 days) were investigated. The specific surface area of rice starch significantly decreased firstly then stabilized during growth due to increasing granular size. The pore volume decreased from 5.40 cm3/g at 6th day after anthesis (DAA-6) to 3.02 cm3/g (DAA-46). More starch granule-associated proteins (SGAPs) accumulated on the surface and in channels. Swelling power decreased by 46 %, whereas the flow behavior index (n) decreased by 32 % in upward curve during starch development from DAA-6 to DAA-30. Tan δ first dropped then remained steady at DAA 22–34 and lightly rebounded at the final stage, indicating that starch in the middle stage tended to have greater viscoelastic gel behavior at all sweeps. Mature starch showed lower in vitro hydrolysis rate and exhibited stronger enzymatic resistance. The results showed that granular surface features of rice starch may be an essential factor in determining rheological behavior and resistance to hydrolysis.

Clinical effects of IPCH after the surgery for ovarian cancer at the middle or advanced stage and its impacts on tumor markers and immune functions.

To evaluate the clinical effects of intraperitoneal chemohyperthermia (IPCH) in the treatment of postoperative patients with advanced stage ovarian cancer, and its impacts on tumor markers and immune functions. This is a retrospective study. One hundred and twenty patients with advanced stage ovarian cancer received in Shanghai 7th People's Hospital Affiliated to Shanghai University of Traditional Chinese Medicine from May 10, 2022 to June 10, 2023 were selected and randomly divided into control and study groups (n=60 each group). Patients in the control group were administered routine intravenous chemotherapy, the study group underwent IPCH besides routine intravenous chemotherapy based on the control group. Comparatively analyzed the clinical effects, adverse reaction occurrence rates, and variations in relevant observation targets, the tumor marker after and before the treatment. Total efficacy in the study and control groups are proved to be with statistically significant differences. The occurrence of adverse reactions proved that no significant differences is seen between both groups. After the treatment, CEA, CA19-9, and CA125 levels in patients of the study group are apparently lower than those in the control group, showing statistically significant differences; expression levels of CD3+, CD4+ and CD4+/CD8+, in the study group were enormously above those in the control group after the treatment, with statistically significant differences. IPCH has the potential to effectively enhance comprehensively clinical therapeutic effects among postoperative patients with ovarian cancer, significantly improve patients' immune states, and evidently reduce expression levels of various tumor markers.

Factors affecting the desire to work among elderly people in Thailand

Globally, the number of elderly people is increasing. It is important for elderly people to be financially active to enhance their values and health. Therefore, this study aimed to explore the factors affecting the desire to work among elderly people in Thailand. The present study was a cross-sectional analytical study conducted using the 2017 Elderly Population Survey database of the National Statistical Office, which includes 32,035 individuals. The statistical analysis was performed by a generalized linear mixed model (GLMM). This study revealed that 31.05% of the elderly participants desired to work (95% CI: 30.54-31.55). Statistically significant factors influencing this desire included demographic characteristics such as gender (female, AOR=1.76), age groups (middle elderly stage, AOR=3.13; late elderly stage, AOR=8.88), and literacy (ability to read and write, AOR=1.21). Marital status also played a role, with married (AOR=1.39) and single (AOR=1.37) individuals showing a higher desire to work. Health-related factors were equally important. Those with better physical health had a much higher likelihood of wanting to work compared to those with very poor health (AOR=5.81). Furthermore, engaging in exercise (AOR=1.30), participating in social groups (AOR=2.50), and community activities (AOR=1.11) were positively associated with the desire to work. Sensory abilities, such as clear vision (AOR=1.14) and hearing (AOR=1.42), as well as residing in rural areas (AOR=1.23), also influenced this desire. Approximately one-third of the elderly people were willing to work. Factors that were associated with the desire to work included gender, age, reading and writing ability, marital status, physical health, engaging in exercise, ability to participate in social groups, participation in community activities, vision and hearing ability and location of residence. Therefore, a multidisciplinary approach that considers these factors should be undertaken to promote suitable work for elderly people to enhance their values and health.

Comparative transcriptomic insights into key genes for biomass production and lipid synthesis in Chlorella sorokiniana mutated by argon and air atmospheric and room temperature plasma at different culture stages: Common mechanisms and unique differences

Metabolic mechanisms driving rapid lipid production in atmospheric and room temperature plasma-mutagenized Chlorella sorokiniana remain unclear, hindering improvement in lipid productivity through genetic modification. This study investigated two dominant strains, ArX13 and AirX12, mutated by argon and air ARTP, for growth, lipid production, and transcriptomic changes across various culture stages. Results showed that biomass and lipid contents peaked in the late stage, with ArX13 and AirX12 achieving final biomass of 0.71 g/L and 0.70 g/L, and lipid content of 58.57 % glipid gbiomass−1 and 46.90 % glipid gbiomass−1, 2.20 and 1.77 times higher than the control, respectively. The maximum biomass and lipid productivity occurred at the mid-stage, with ArX13 and AirX12 showing biomass productivity of 0.025 gbiomass L−1 day−1 and 0.024 gbiomass L−1 day−1, and lipid productivity of 17.79 mglipid L−1 day−1 and 11.40 mglipid L−1 day−1, respectively. Transcriptomic analysis revealed minimal changes of gene expression during early and late stages, but significant biomass and lipid synthesis during the middle stage. Key genes like PDHB, ATP6A, LSC1 and OGDH were identified in the PPI network throughout the culture cycle, with PDHB remarkably promoting lipid precursor production, up-regulated 8.37 and 4.99-fold in M_ArX13-M_X0 and M_AirX12-M_X0, respectively. In addition, high expression of photosynthesis-related genes (psaL, psaO, psaD, psaK, psbP) contributed the superior lipid production for the argon-based ARTP case, highlighting common and intrinsic mechanisms regulating microalgal lipid accumulation under different ARTP mutations. This study shows that the selection of appropriate ARTP gases can maximize the lipid production of microalgal, and the discovery of some key genes can provide a theoretical basis for the selection of target genes for microalgal research, which is of great significance for promoting the research and development of microalgal lipid engineering.

Reducing costs or increasing efficiency? Unveiling the effects and mechanisms of the digital economy on sustained green innovation

This study examines the impact of the digital economy on sustainable green innovation in China, with a focus on the mediating roles of debt financing costs and resource allocation efficiency. Leveraging a comprehensive dataset of 24,741 firm-year observations from 2008 to 2022, we utilize fixed-effects regression models to analyze the relationships between the digital economy, debt financing costs, resource allocation efficiency, and sustainable green innovation. The results demonstrate that the digital economy positively influences sustainable green innovation, with this effect being partially mediated by reductions in debt financing costs and improvements in resource allocation efficiency. Specifically, the digital economy lowers financing costs and optimizes resource allocation, which collectively enhances green innovation sustainability. The findings remain consistent across various endogeneity and robustness checks, including instrumental variable approach, lagged effects, heckman two-stage method, sample adjustments, alternative measures, and model specifications. Additionally, heterogeneity tests reveal that the digital economy's positive effect is stronger for firms in the early and middle stages of their life cycle and for those operating in less-polluting industries. These insights contribute to the growing literature on digital technologies and sustainable development, offering valuable implications for managers and policymakers aiming to harness the digital economy for advancing sustainable green innovation.

Effects of Combined Nitrogen-Phosphorus on Biomass Accumulation, Allocation, and Allometric Growth Relationships in Pinus yunnanensis Seedlings after Top Pruning.

Pinus yunnanensis (Franch), a species endemic to southwestern China, provides significant ecological and economic benefits. The quality of afforestation can be enhanced by promoting high-quality sprout growth. This study analyzed the effects of six fertilization treatments following top pruning: T1 (N: 0 g/plant-1; P: 0 g/plant-1), T2 (N: 0 g/plant-1; P: 2 g/plant-1), T3 (N: 0 g/plant-1; P: 4 g/plant-1), T4 (N: 0.6 g/plant-1; P: 0 g/plant-1), T5 (N: 0.6 g/plant-1; P: 2 g/plant-1), and T6 (N: 0.6 g/plant-1; P: 4 g/plant-1). The accumulation and allocation of aboveground biomass in roots, stems, and leaves of P. yunnanensis were measured, as well as changes in biomass per plant at 90 days (early stage), 180 days (middle stage), and 270 days (late stage) post-fertilization. At 90 days, root biomass accumulation in T3 was significantly higher, by 13.31%, compared to that in T1 (p < 0.05). The growth rates of stem and plant biomass followed the order T6 > T1 > T3 > T5 > T4 > T2. The biomass of sprouts and individual plants exhibited allometric growth under T1, T5, and T6 treatments. At 180 days, needle biomass allocation in T1 and T4 increased by 7.47% and 8.6%, respectively, compared to 90 days. Combined nitrogen-phosphorus fertilization significantly influenced aboveground biomass allocation, promoting growth more effectively than other treatments. By 270 days, the stem and individual biomass in T2 and T3 treatments showed significant differences (p < 0.01) compared to other treatments. Overall, root, stem, and sprouts were primarily influenced by phosphorus fertilization, while nitrogen fertilization notably promoted needle and leaf growth in later stages. The aboveground components were more affected by phosphorus fertilization. The combination of nitrogen and phosphorus fertilizers enhanced early-stage stem and sprouts, as well as late-stage root development.

Kinetic analysis and calculation correction methods for moisture evaporation rate in pine lignocellulosic biomass

This study investigates the kinetics of moisture evaporation in pine wood during the drying stage, focusing on analyzing thermogravimetric (TG) curves. The research is based on the kinetic rate model and TG curves obtained at various heating rates, specifically 5, 10, 15, and 20 K/min for the heat release rate, within a temperature range from room temperature to 473 K. Utilizing thermogravimetric experiments and the kinetic rate model, the apparent activation energy and pre-exponential factor are calculated. Further refinement of these calculations is achieved using the Nelder-Mead algorithm. The results show good agreement between the average values of the apparent activation energy (37.88 kJ/mol) and pre-exponential factor (4458.20 s−1) and experimental measurements in the initial and later drying stages, with discrepancies noted in the middle stage. Establishing a relationship between the correction coefficients of these parameters and the heating rate leads to a reduction in calculation errors. Notably, the pre-exponential factor is found to be influenced by heating rates, while the apparent activation energy remains relatively stable. Moreover, the errors are significantly reduced after correction, and the error curve of 10 K/min is the most significant. Overall, the proposed correction method holds promise for accurately calculating moisture evaporation rates in lignocellulosic biomass, offering valuable insights for biomass drying applications.

Catalytic effects of transition metal oxides on HTPB-based fuel polymer matrices

Low regression rate due to difficult pyrolysis is a major challenge in the practical application of terminated hydroxyl‑terminated polybutadiene (HTPB)-based fuels in hybrid rocket propulsion. Accelerating the decomposition of the polymer matrix is an effective method to improve the regression rate of HTPB fuels. To determine the difference in combustion performance between different transition metal oxides loaded HTPB-based fuels, nickel oxide (NiO), ferric oxide (Fe2O3), copper oxide (CuO) and manganese dioxide (MnO2) were introduced into the HTPB matrix at 5% mass fraction. The experimental results showed that the metal oxides could significantly catalyze the pyrolysis of HTPB-based fuels and enhance the fuel regression rate, and the catalytic effect was mainly concentrated in the middle and late stages of the thermal decomposition process of polybutadiene components. Among the four transition metal oxides, CuO and MnO2 showed better catalytic effects on the combustion performance of HTPB-based fuels in the high oxygen mass flux region, while NiO showed better catalytic effects in the low oxygen mass flux region. The present study compares the regression rate of fuel grains modified with different transition metal oxides, which provides a basis for the selection of future catalysts, verifies the catalytic effect of the transition metal oxides on the combustion of HTPB-based fuels and further analyzes the combustion reaction mechanism of the fuels.

Impact of salivary flow inhibition on masticatory behaviours in healthy individuals.

It remains unclear how the salivary flow and the fat content of food affect bolus formation during mastication. We aimed to clarify: (1) how hyposalivation affects jaw-closing and hyoid-elevating muscle activities in bolus formation, and (2) if the effect of hyposalivation on muscle activity depends on the fat content of food. Eighteen healthy male volunteers were instructed to freely ingest four test foods: Plain, Fat without seasoning, Fat with seasoning, and Soft rice crackers. Masseter and suprahyoid electromyographic activities were recorded before and 30 min after the administration of atropine sulfate, a muscarinic receptor antagonist that induces hyposalivation. Hyposalivation extended the masticatory duration significantly in all the test foods except Fat with seasoning. Masticatory cycle time was significantly longer with vs without hyposalivation for the Soft (p = .011). Suprahyoid activity/cycle was significantly greater with vs without hyposalivation (p = .013). Masticatory cycle time was significantly longer at the late stage with vs without hyposalivation for the Soft (p < .001). Suprahyoid activity/cycle was significantly greater at the middle (p = .045) and late stages (p = .002) with vs without hyposalivation for the Soft and greater at the late stage with vs without hyposalivation for the Plain (p = .043). Changes in masticatory cycle time and suprahyoid activity/cycle for these foods had significantly positive relationship (p < .001). Hyposalivation-induced changes in masticatory behaviours resulted from the middle and late stage suprahyoid activity. Fat content and seasoning compensate for salivary flow inhibition.

Episodic fluid charging and mixing triggers calcite-bearing agates in the Permian Emeishan Basalt, SW China

ABSTRACT Agate, a distinctive form of banded chalcedony, derives its characteristic appearance from the deposition of silica and the presence of impurities. A significant variety of agate-bearing calcite was identified in the Permian Emeishan Basalt located in the southwestern Sichuan Basin. This calcite-bearing agate provides valuable insights into the complex interplay and evolution of fluids and minerals. This study aims to provide a detailed description and analysis of the microscopic textural and geochemical characteristics of the agate, while elucidating the sequence of mineral deposition, fluid properties, and the genetic mechanism underlying its formation. The findings reveal that the agate primarily consists of lamellar calcite and banded chalcedony, exhibiting a variety of textures, thicknesses, and colours. Through the analysis of the transformation and precipitation of epidote and allanite, and the identification of four types of calcites and five micro-silica textures, it has been confirmed that the early stage of fluid in geodes involved the mixing of meteoric water with post-magmatic hydrothermal fluid. The middle and late stages involve the mixing of magmatic-hydrothermal fluid with organic-acid fluid. The charging of silica-rich hydrothermal fluids and the generation of hydrocarbons from organic matter cause fluctuations in SiO2 concentration, pH, and crystallization rates, contributing to the diversity of silica minerals, such as chalcedony and quartz. The interlayered growth observed between chalcedony and calcite is attributed to secondary metasomatism, which occurs after the dehydration and transformation of chalcedony due to increasing temperatures. Notably, the internal texture of the agate is somewhat influenced by pressure variations caused by the episodic charging of the fluid.

P18: BDNF levels and affective disorders as a marker of vulnerability to developing cognitive impairment in the Chilean adult population

Summary: Disorders related to progressive cognitive decline constituting an important cause of global death and disability-adjusted life years because conditions are also associated to impairment of several brain functions, psychological and behavioral changes, regardless of economic status. Brain-derived neurotrophic factor (BDNF) is a neurotrophin highly relevant in memory, learning and neuroplasticity processes in adults. The amount of plasma BDNF has been considered to partly reflect its secretion in the brain. Its deficiency is associated with affective disorders and neurodegenerative pathologies such as Alzheimer disease and Parkinson’sdisease.The aim of this study was to identify quantifiable biomarkers (serum levels of BDNF) and clinical marker (state of depression and anxiety) that allow early detection of cognitive impairment risk. We made an analytic and transversal study with a representative sample (n:307) of the population over 50 years old in the south of Chile (X region). We determine the cognitive condition of the population by applying cognitive functionality tests, such as the minimental status examination (MMSE) test and identify demographic and psychosocial characteristics that constitute impairment cognitive risk. Subsequently, we determined depression status (scale of Yesavage) and anxiety status (Beck inventory), and finally we made a quantitative determination of human BDNF at the blood level using ELISA technique.Our results revealed that 26.7% of the participants exhibited some degree of cognitive impairment, being higher in women (55.7%) with average age of 70,7. A 18,2% of subjects manifested indicators of depression and 33,2% have a very hight level of anxiety. The correlation analysis revealed a significant positive correlation between MMSE test (p &lt; 0.001) and both BDNF plasma levels (p &lt; 0.001) and education level (p &lt; 0.001) scores. The results additionally indicated a negative correlation between cognitive functions and age range/anxiety state, suggesting low age level/hight level of anxiety in subjects with more pronounced cognitive decline (p &lt; 0.001),. In consistent, the results of our study point towards decreases plasma BDNF levels and hight levels of anxiety in cognitive impairment subjects compared with cognitive normal subjects, which may be due to the early and middle stages of neurodegeneration process.

Research on moisture absorption characterization of wound composites based on surface concentration modified model

Abstract Four groups of hygroscopic experiments of T700/epoxy composite wound rings at temperatures and humidities of 45°C/60%, 45°C/90%, 70°C/60%, and 70°C/90% were completed in order to study the moisture absorption characterization. Surface concentration correction models characterized by different types of functions such as linear, quadratic, sinusoidal, exponential, and others were proposed to establish a “three-stage” moisture absorption model, in which the initial stage was smooth, the middle stage grew rapidly, and the later stage tended to equilibrium. The theoretically predicted hygroscopic curves derived from quadratic and exponential functions were in good agreement with the experimental data, which revealed the difference in the moisture absorption characterization between the wound rings with high fiber volume and that of the laminates and fabrics and provided a basis for the prediction of the mechanical degradation and life of the wound composites in hygrothermal environments.

Characterization of Male Flower Induction by Silver Thiosulfate Foliar Spray in Female Cannabis at the Middle Reproductive Stage for Breeding.

Cannabis (Cannabis sativa) is a versatile crop belonging to the Cannabaceae family, and is dioecious, typically with separate male and female plants. The flowers of female plants, especially the trichomes, accumulate relatively higher contents of cannabinoids compared with those of male plants. For this reason, to obtain seeds that are genetically female, it is desirable to induce the development of male flowers on a female plant that produces genetically female haploid gametes. Silver thiosulfate (STS) is a highly effective chemical for male flower induction. We investigated male flower induction in three commercial cultivars of female cannabis (Spectrum303, SuperwomanS1, and CBGambit) regarding the treatment frequency, stage of application, and concentration of STS applied as a foliar spray. All three cultivars showed adequate induction of male flowers in response to 1.5 mM STS applied at the early reproductive stage. In particular, SuperwomanS1 was most highly responsive to induction of male flowers, even when treated with 0.3 mM STS at the early reproductive stage. Treatment with three applications of STS was more effective compared with a single application, but a single application of 1.5 mM STS at the early reproductive stage was sufficient for male flower induction. A single STS application during the middle stage of reproductive growth was inadequate for induction of male flowers. However, 6 weeks after three applications of STS, CBGambit exhibited approximately 54% male flower induction at 0.3 mM STS, Spectrum303 showed approximately 56% induction at 3 mM STS, and SuperwomanS1 yielded approximately 26% induction at 1.5 mM (expressed as percentage of total number of individuals with the induced male flowers). Pollen stainability tests using KI-I2 solution and Alexander's staining showed high pollen viability with over 65% at different single STS concentrations, indicating that pollen grains induced by STS have sufficient viability for the self-pollination. This study demonstrated that different cultivars of cannabis respond diversely to different STS concentrations and highlighted the potential benefits of three STS applications during the middle reproductive stage for cannabis breeding.

Direct and indirect effects of urbanization on vegetation: A survey of Yunnan central urban Economic Circle, China

Urbanization affects vegetation distribution by changing land cover. However, it also significantly changes urban water and heat conditions, affecting vegetation growth and development. Vegetation coverage is an effective indicator of vegetation growth. This study analyzed trends in vegetation coverage over the past 35 years, taking the Yunnan Central Urban Economic Circle as the study area. The study was based on applying the pixel dichotomy model and correlation statistical analysis on joint Landsat 5, 7, and 8 long- term remote sensing data, meteorological, and land use data. The direct and indirect effects of urbanization on vegetation coverage were also further explored by constructing an urbanization impact framework. The results revealed that: (1) The urban area during urbanization from 1986 to 2021 increased by 720.29 km2. There was a continuous decline in vegetation cover in and around urban areas, which intensified with accelerating urbanization, with the effect being more pronounced in suburban areas. (2) There were consistent increasing trends in urbanization’s direct and indirect effects on vegetation over the last 35 years, with average negative and positive effects of − 0.41 and 1.59, respectively. (3) Direct effects could mainly be attributed to the expansion of impervious surfaces, whereas the main indirect effect during the late urbanization period (2011–2020) was increasing average temperature. The average temperature showed a correlation coefficient with urbanization of 0.7767, and this relationship showed seasonal heterogeneity due to the significant growth of urban vegetation in summer and winter. (4) Cities that developed faster showed better environmental planning and construction. The direct and indirect effects of urbanization on vegetation during the early and middle stages were higher in cities developing at slow and moderate rates, with this trend reversing only in the later stages of urbanization. The results of this study can increase understanding of the effect of urbanization on vegetation coverage in the Yunnan Central Urban Economic Circle. They can assist in improving urban green spaces and urban ecological resilience.

A multi-objective dynamical artificial bee colony for energy-efficient fuzzy hybrid flow shop scheduling with batch processing machines

Energy-efficient hybrid flow shop scheduling problem (EHFSP) with batch processing machines (BPMs) is rarely considered, let alone EHFSP with BPMs and uncertainty. In this study, an energy-efficient fuzzy hybrid flow shop scheduling problem (EFHFSP) with BPMs at a middle stage and no precedence between some stages is solved, and a multi-objective dynamical artificial bee colony algorithm (MODABC) is presented to simultaneously minimize fuzzy makespan and total fuzzy energy consumption. To produce high quality solutions, a swarm decision is used to dynamically determine the employed bee swarm and onlooker bee swarm, a dynamical employed bee phase is implemented, and an onlooker bee phase with adaptive communication is given. The diversity reinforcement strategy and an adaptive scout phase are also adopted. Extensive experiments are conducted, and the optimal combination of key parameters for the proposed algorithm is determined by the Taguchi method. The computational results demonstrate that the new strategies of MODABC are effective, and MODABC is very competitive in solving the considered EFHFSP.

Die Stellenbosche Heyns: Nagedink oor die vroeë, middel en latere jare van ’n akademiese loopbaan

This contribution is structured in the genre of an academic letter to a deceased colleague, in this case Prof. Johan Adam Heyns (1928–1994). He was appointed for a short period from 1966 to 1970 as a senior lecturer at the Faculty of Theology at Stellenbosch University. This contribution offers a reappraisal of this period in the academic career of Prof. Heyns. His main focus at the time, in line with his teaching duties, was on apologetics and, to some extent, also ethics. The author engages with Prof. Heyns’s views at the time and offers a sixfold mirror to position this phase of his career, namely in terms of the tensions between orthodoxy and modernity, between the philosophical influence of Henk Stoker and the theological influence of Herman Bavinck, and between the implementation of apartheid and the struggle against that. This mirror is held up in order to reflect on the early, middle and later stages of any academic career including that of the author, to contrast the radiance and risk of youthful academic rigour and the wisdom but also the rigidity that may come with mature age.Intradisciplinary and/or interdisciplinary implications: The research done, is not of an interdisciplinary nature. This article contributes to a growing corpus of literature assessing the legacy of Prof. Johan Adam Heyns.

Experiments on Steam-Assisted Gravity Drainage with Coinjection of Noncondensable Gases during the Middle and Later Stages of Its Development in Super-Heavy Oil Reservoirs

Summary The problems of oil/steam ratio (OSR) and oil production decline are prominent during the middle/later stages of steam-assisted gravity drainage (SAGD) in superheavy oil reservoirs. Using noncondensable gas (NCG) by SAGD can reduce heat loss to the overburden and reduce carbon dioxide (CO2) emissions. However, to date, laboratory experiments have mainly been conducted to simulate NCG coinjection with steam in the early stage of SAGD. There has been limited research on the NCG coinjection into the mature SAGD steam chamber. For this study, five sets of 2D physical simulation experiments are introduced and designed based on NCG coinjection with steam into the sand-packed model. The influencing factors of steam-assisted and gas push (SAGP) are analyzed through experiments, including different NCGs [methane (CH4), CO2, and nitrogen (N2)] and coinjection of NCG at different times (i.e., during the lateral expansion and descending stages of the steam chamber). The results indicate that the mechanism of SAGP includes reducing the steam consumption, maintaining the pressure balance of the steam chamber, reducing the partial pressure of the steam, maintaining the quality of the steam, and improving the displacement efficiency of the steam during the lateral expansion of the steam chamber. In addition, the top gravity displacement is the primary mechanism during the later stage of pure gas injection, which manifests that the residual oil at the bottom of the steam chamber is further recovered by using the residual heat of the the steam chamber. Compared with SAGD, the recovery of CO2-assisted SAGD (CA-SAGD), CH4-assisted SAGD (MA-SAGD), and N2-assisted SAGD (NA-SAGD) increased 6.8%, 5.4%, and 4.4%, respectively. The NCG coinjection effect was better during the descending stage of steam chamber, and the oil recovery was 4.7% higher than that during the lateral expansion stage. The selection of NCG and coinjection timing plays a crucial role in improving the ultimate oil recovery and OSR during the middle and later stages of SAGD in superheavy oil reservoirs.

Tectonic-climate-wildfire coupling during the Miocene in the northeastern Qinghai-Tibetan Plateau

The uplift of the Qinghai-Tibetan Plateau (QTP) is one of the most significant geological events in the Cenozoic era. While most studies have focused on the latitudinal differences in the uplift process of the QTP, there has been scant attention to its longitudinal differentiation. The Miocene epoch is pivotal for understanding both the uplift of the QTP and associated climatic changes. Wildfire events not only record changes in vegetation composition but also reflect climatic fluctuations and their driving forces. However, investigations into the interactions among these factors remain limited. This study aims to explore the coupling between the uplift of the QTP, climatic changes and wildfire frequency (or intensity) from northeastern QTP by analyzing microcharcoal concentrations and length-to-width ratios from the Miocene Youshashan Formation in Wulan County, Qinghai Province. The results indicate that the development of wildfires could be divided into three stages. Compared with the intervals 18–15 Ma and 11–8.7 Ma, the middle stage (15–11 Ma) experienced the highest wildfire frequency. This finding underscores the synchronous and close relationship between wildfire occurrences, the uplift of the QTP, and consequent climatic fluctuations. The ratio of length-to-width of microcharcoal indicates that Miocene wildfires in the Wulan Basin primarily occurred at the transitional zones between forests and grasslands. Moreover, the highest peak of wildfire events at six sites gradually shifted from the northeastern to the northwestern QTP from 18–8.7 Ma. This fact demonstrates spatiotemporal disparities in wildfire events from northern QTP, likely stemming from asynchronous uplifts there.