Stable Period Research Articles

Asimina triloba seeds as a feedstock for energy conversion: Optimizing yield rate and characterizing fuel properties

In the present study, waste Asimina triloba seeds are proposed as a potential feedstock for biodiesel production, with the optimization of transesterification process parameters aimed at achieving higher yield rates. While previous studies have explored the use of Asimina triloba biodiesel for engine applications, this study stands out as the first to optimize transesterification process parameters for increased yield and to conduct comprehensive fuel characterization alongside storage stability analysis. The transesterification process parameters such as the methanol-oil molar ratio, catalyst volume concentration, reaction process temperature, and reaction process time are optimized by employing the response surface methodology. The response surface methodology analysis revealed that the proposed model is highly significant, with a coefficient of determination approaching unity. To achieve maximum biodiesel yield, the recommended parameters are a methanol-oil molar ratio of 14.7:1, a catalyst concentration of 2.4%, a reaction temperature of 81.3?C, and a reaction time of 138.8 minutes. Under these optimal conditions, the projected yield is 94.35%, aligning closely with experimental observations of 94.4%. The Fourier-transform infrared spectroscopy analysis underscored the substantial presence of carbon-based constituents in biodiesel, while the gas chromatography-mass spectrometry analysis revealed octadic-9,12-dienoic acid as the primary contributor. Furthermore, the stability profile demonstrates an extended stability period, complemented by physicochemical properties that align with the biodiesel standards specified by ASTM.

Research on the response of bitumen binder and bitumen mastic to physical hardening effect based on rheological properties

Bitumen materials will occur a physical hardening effect when stored isothermally in a low-temperature environment, and ignoring the physical hardening factor has become one of the important reasons for premature cracking of asphalt pavement during the service period. This paper investigates the response of bitumen binder and bitumen mastic to physical hardening effects at different storage temperatures and times using the bending beam rheometer and dynamic shear rheometer. The response of the material to physical hardening effects is analyzed through temperature index system changes, mathematical model fitting, and stiffness master curve fitting. Results indicate that the response of the material to physical hardening effects can be classified into two stages: the rapid growth and the gradual stabilization periods. The response time of these two stages is related to factors such as aging degree and storage temperature. The physical hardening effect will cause the temperature loss of the material at low temperature, and its influence law on TS60=300MPa and Tm60=0.300 is different. It is recommended to extend the isothermal storage time specified in the test from 1 h to 9 h, considering the time cost and the change in temperature index. Moreover, the stiffness master curve study revealed the occurrence of the "tail drift" phenomenon.

Exploring Surfactant-Enhanced Stability and Thermophysical Characteristics of Water-Ethylene Glycol-Based Al2O3-TiO2 Hybrid Nanofluids

This study presents an empirical investigation into the impact of surfactant's enhanced stability and thermophysical characteristics of water-ethylene glycol (60:40) based Al2O3-TiO2 hybrid nanofluids. It aims to shed light on the nanofluid's behavior, mainly how surfactants affect its stability and thermal performance, thus contributing to advancements in heat transfer technology and engineering applications. The growing interest in nanofluids, which involves blending nanoparticles with conventional base fluids, spans diverse sectors like solar energy, heat transfer, biomedicine, and aerospace. In this study, Al2O3 and TiO2 nanoparticles are evenly dispersed in a DI-water and ethylene glycol mixture using a 50:50 ratio with a 0.1 % volume concentration. Three surfactants (SDS, SDBS, and PVP) are utilized to investigate the effect of the surfactants on hybrid nanofluids. The study examines the thermophysical characteristics of these hybrid nanofluids across a temperature range of 30 to 70 0C in 20 0C intervals to understand their potential in various industrial applications. The results show the highest stability period for nanofluids with PVP compared to nanofluids with surfactant-free and other surfactants (SDS, SDBS). The thermal conductivity is slightly decreased (max 4.61%) due to PVP surfactant addition compared to other conditions. However, the nanofluids with PVP still exhibit more excellent thermal conductivity value than the base-fluid and significantly reduced viscosity (max 55%). Hence, the enhanced thermal conductivity and reduced viscosity with improved stability due to PVP addition significantly impact heat transfer performance. However, the maximum thermal conductivity was obtained for surfactant-free Al2O3-TiO2/Water-EG-based hybrid nanofluids that reveal a thermal conductivity that is 17.05 % higher than the based fluid. Instead, the lower viscosity of hybrid nanofluids was obtained at 70 0C with the addition of PVP surfactant. Therefore, adding surfactants positively impacts Al2O3-TiO2/Water-EG-based hybrid nanofluids with higher stability, enhancing thermal conductivity and reducing viscosity compared to the based fluids. The results show that adding surfactants at a fixed volume concentration affects thermal conductivity at low temperatures and viscosity at high temperatures, suggesting that these fluids might be used as cooling agents to increase pumping power in industrial applications.

Развитие проблематики отечественной экономической психологии в научном творчестве А.Л. Журавлева

<p style="text-align: justify;"><strong>Objective</strong>. The purpose of this article is to analyze the spectrum of issues developing by the academician of the Russian Academy of Sciences and of the Russian Academy of Education A.L. Zhuravlev himself and to consider the questions elaborating under his guidance – with his co-workers and students in different periods of his scientific work; the research was conducted from the perspective of analyzing the processes of formation and development of the domestic economic psychology problem field. <br><strong>Background</strong>. The existing rules of development of socio-economic systems, in particular their cyclical nature (alternation of stable and crisis periods, uneven changes in the system), indicate the actuality of historical and psychological research in the field of economic psychology in order to predict economic, psychological and socio-psychological dynamics in changing geopolitical and socio-economic conditions of society. <br><strong>Results. </strong>Changes in the management of country’s economic life in the 80s of the last century, the subsequent economic transformations in society, crises and global processes in the world economy are considered as social factors that actualize the research of socio-psychological and economic-psychological phenomena in the scientific work of A.L. Zhuravlev. Among them are: psychological readiness of the population for cardinal economic changes, the relationship of socio-psychological and economic dynamics, patterns and mechanisms of economic socialization and economic self-determination, psychological resources of economic development of society and other phenomena. <br><strong>Conclusions. </strong>Three main stages in the development of the issues of domestic economic psychology presented in the scientific work of A.L. Zhuravlev was reveled. The connection of the studied economic-psychological and socio-psychological phenomena with the socio-economic dynamics of public life is shown.</p>

Sustainable Livelihoods in Peatland of Central Kalimantan Province, Indonesia: Analysis of Resource Utilization Options in Buntoi Village, Basarang Jaya Village, Sabangau Permai Village, ond Karang Sari Village

Peatland resources in Central Kalimantan have long been utilized by the local communities for various activities such as agriculture, gathering, hunting, and timber extraction. The successful exploitation of peatland prompted the Indonesian Government to develop the region through a transmigration program, providing new settlements for people from Java, Madura, and Bali islands who were initially have no experience cultivating peatland. Land suitability issues have resulted in surprises, stress, and a decline in livelihoods among transmigrant populations, particularly concerning the failures in agriculture, especially in cultivating rice, the primary staple food for Indonesians. This research aims to examine the sustainability of livelihoods, determine the conservation aspirations and perceptions of stakeholders, and present alternative land use scenarios. Four villages were selected as samples, including a local village (Buntoi), two migrant villages in peatlands (Basarang Jaya and Sabangau Permai), and one migrant village outside the peatland area (Karang Sari). Data were obtained through interviews and group discussions involving farmers, entrepreneurs, and government officials. The research findings indicate that agriculture on peatlands can be developed through three stages of evolution: the early period, transition and recovery period, and stability or failure period. The stability period may take a long time, up to 20 years, as experienced by farmers in Basarang Jaya. This study provides insights into the sustainability of livelihoods and land use aspirations in Central Kalimantan.
 Keywords: Livelihood, peatlands, sustainable, utiliztion

Comparison of the Learning Curve between Uniportal and Robotic Thoracoscopic Approaches in Pulmonary Segmentectomy during the Implementation Period Using Cumulative Sum Analysis.

The aim of this retrospective study was to compare the learning curve and perioperative outcomes between the two approaches uVATS and RATS during their implementation periods. The uVATS group included 77 consecutive uVATS segmentectomies performed by HI between February 2019 and June 2022, while the RATS group included 30 between July 2022 and September 2023. The patient characteristics, perioperative outcomes, and learning curves were compared between the two groups. The learning curve was evaluated using operative time and cumulative sum (CUSUMOT) analysis. Most patient characteristics and perioperative outcomes were equivalent between the two groups. In the uVATS group, after a positive slope was observed until the 14th case (initial period), a plateau was observed until the 38th case (stable period). Finally, a negative slope was observed after the 38th case (proficiency period). In the RATS group, after a positive slope was observed until the 16th case (initial period), a plateau was observed until the 22nd case (stable period). Finally, a negative slope was observed after the 22nd case (proficiency period). In segmentectomy, a surgeon reached the proficiency period earlier in RATS than in uVATS, although the trends to the stable period were similar.

Minimum wage and spillover effects in a minimum wage society

AbstractMinimum wage policies are widely implemented in developing countries, but their consequences remain uncertain. This study empirically investigates the impact of the minimum wage on monthly income inequality and its spillover effects in Turkey between 2004 and 2022, utilizing comprehensive micro data. We aim to shed light on the impact of national minimum wage policies by examining their diverse influences on the wage structure within the country. Our findings reveal that the minimum wage significantly reduces income disparities, particularly among formal workers at the lower and upper end of the wage distribution. While wage gaps below the median wage decline, those above it experience a slower growth rate, ultimately leading to wage convergence. Notably, this effect is more pronounced during macroeconomic instability from 2016 to 2022, compared with the relatively stable period of 2004–15. Moreover, the outcomes differ depending on individual attributes like gender, age, education, and other relevant factors. Furthermore, we observe tentative evidence of a lighthouse effect to some degree: the minimum wage seems to exert an equalizing influence on the wage structure of workers in the informal sector beyond a certain percentile.

Changes of Japanese Marxist Economic Thoughts in Post-War

After the Second World War, Japanese Marxist economic thoughts was recovered and made great development, gradually forming four schools of "Orthodox", "Uno", "Civil Society" and "Mathematical Economics". According to the focus of different periods and the characteristics of the historical background, it can be divided into the recovery period in the early stage after the war, the trough period after the revolutions of 1989 in the Soviet Union and the stability period since the bubble economy.

How the media matters for the economic vote: Evidence from Britain

Existing research finds that economic news can influence how citizens evaluate their governments, but the relative importance of different channels through which this effect arises, and how this may vary across contexts, remains unclear. Drawing on media dependency theory, I argue that we should observe larger media effects on citizens’ economic evaluations during periods of economic stability than during crises. Moreover, during crises, we should observe larger media effects on citizens’ evaluations of governing parties’ responsibility for, and handling of, the economic situation, than on their subjective economic evaluations. Additionally, these effects should be stronger among governing party supporters. Analysis of British public opinion leading up to and following the 2007–8 global financial crisis provides empirical support for this theory. These findings have implications for our understanding of how the media matters for the economic vote, as well as voters’ ability to use elections as instruments of accountability during crises.

Holocene geochronology and sedimentation in the southern Brazil shelf depocenters

Latitudinal modulation of proxies for environmental changes over the mid to late-Holocene was analyzed in four cores retrieved along mud depocenters on the South Brazilian Shelf, between 33.8°S and 25.1°S. To the south, early to mid-Holocene northwards migrations of the Southern Westerly Wind Belt (SWWB) and the post-LGM sea level rise are expressed as an increase in sand content, while the low Ti/Ca and Ti/K ratios point to dry climatic conditions. During the mid-Holocene, the sea level highstand coincided with a period of stabilization in atmospheric conditions, which led to a pulse of coarser sediment deposition in the southern area. In 3000 cal yr BP, a rapid and latitudinally simultaneous increase of Ti/Ca and Ti/K mark the late-Holocene more humid and warmer onset linked to an intensification of the South American Monsoon System (SAMS). Across-shelf branches of the Brazil Current (BC) that mix with the Plata Plume Water (PPW) to flow northwards could be responsible for sediment remobilization leading to clay depletion in the south extreme of the study area. The amplitude of grain size changes gets lower as we go further north, suggesting a buffering effect exerted by the distance to the source.

𝑃c𝜀𝜅max-Means++: Adapt-𝑃 Driven by Energy and Distance Quality Probabilities Based on 𝜅-Means++ for the Stable Election Protocol (SEP)

Attaining a prolonged network lifetime, maximized coverage, and high performance are vital design factors that have to be maintained in a Wireless Sensor Networks (WSN). Such factors are dependent on the stability and optimality of the protocol employed to formulate Sensor Nodes (SNs) into mutual clusters that effectively work around fulfilling specific performance goals. SEP is a heterogeneity-aware protocol implemented based on Low-Energy Adaptive Clustering Hierarchy (LEACH) protocol, designed to prolong the stability period of the network defined by the time interval before the death of the first SN. Nevertheless, adaptability in design is a scheme that has not been extensively applied in the formation of WSN election protocols. Adapt-𝑃 is a probabilistic model for adaptivity designed to evolve the probability of selecting a cluster-head based on the active status of the WSN, represented by the residual energy of and distances between SNs. However, the adaptive probability 𝑃adp formalized in Adapt-𝑃 is developed based on the remaining number of SNs 𝜁 and optimal clustering κmax, yet 𝑃adp does not implement the probabilistic ratios of energy and distance factors in the network. Furthermore, Adapt-𝑃 does not localize cluster-heads in the first round properly because of its reliance on distance computations defined in LEACH, that might result in uneven distribution of cluster-heads in the WSN area and hence might at some rounds yield inefficient consumption of energy. This paper utilizes 𝑘-means++ and Adapt-𝑃 to propose 𝑃c𝜅max-means++ clustering algorithm that better manages the distribution of cluster-heads and produces an enhanced performance. The algorithm employs an optimized cluster-head election probability 𝑃c developed based on energy-based 𝑃𝜂(𝑗,𝑖) and distance-based 𝑃𝜓(𝑗,𝑖) quality probabilities along with the adaptive probability 𝑃adp, utilizing the energy 𝜀 and distance optimality 𝑑opt factors. Furthermore, the algorithm utilizes the optimal clustering 𝜅max derived in Adapt-𝑃 to perform adaptive clustering through 𝜅max-means++. The proposed 𝑃c𝜅max-means++ is compared with the energy-based algorithm 𝑃𝜂𝜀𝜅max-means++ and distance-based 𝑃𝜓𝑑opt𝜅max-means++ algorithm, and has shown an optimized performance in term of residual energy and stability period of the network.

COMBINATIONS AND SEQUENCES OF LIFE TRANSITIONS DURING A 10 YEAR PERIOD AROUND RETIREMENT AGE

Abstract Our lives can be characterized as periods of stability, alternating with events that bring about change of both practical and psychological nature which require some life adjustment. The scope and depth of such life transitions are related to the kind of event, but also to whether it is perceived as positive or negative, occurs together with other events, addresses an entirely new topic or something that is biographically familiar, comes after a long period of stability or if it is an event in a chain of events occurring shortly after one another. Applying a quantitative approach to qualitative interview data from the Swedish German HoT-age project (N=50; mean age=69; 50% men), life transitions were analysed by means of sequential and configural frequency analysis. During an approximate 10-year period around retirement age, the participants experienced in average 3.7 life transitions and 24% of them more than five. Fifteen different kinds of transitions (retirement, relocation, divorce/separation, new partner, chronic illness etc) were recorded. Besides retirement experienced by almost all (96%), relocation (66%), becoming a grandparent (40%) and chronic illness (40%) were most frequent. The transitions significantly more often (p=0.041) occurring in combination were retirement and relocation. Those who had experienced chronic illness often had a sequence of several events preceding the illness recorded as a transition. Those who found a new partner often had a sequence of events after that. Large variation in sequences and distances between events were found. This study contributes with new knowledge on life transitions around retirement age.

ANTIHYPERTENSIVE DEPRESCRIBING AND COGNITIVE FUNCTION IN VA NURSING HOME RESIDENTS: A TARGET TRIAL EMULATION

Abstract Deprescribing is the practice of discontinuing or reducing medication that no longer provides benefits or causes harm. While deprescribing antihypertensives for frail elderly patients has gained interest, its impact on patient-centered outcomes such as cognitive function remains unknown. We emulated a target trial involving 45,183 Veteran Affairs nursing home residents aged ≥65 with stays ≥12 weeks between 2006-2019. Eligible residents must have a 4-week stable medication use period; they were allocated to the deprescribing/control arms, and censored at death, discharge, or two-year follow-up for intention-to-treat analysis. We used the Cognitive Function Scale (CFS) to assess cognitive outcomes, categorizing residents into cognitively intact, mild-, moderate-, and severely-impaired groups. We used an ordinal generalized linear-mixed model to analyze the effect of deprescribing on CFS, adjusting for confounders with 47 baseline covariates using inverse probability of the treatment weights. 1,290 and 11,354 patients were in deprescribing/control arms. At baseline, deprescribing was associated with an increased risk of worse cognitive function (OR=1.168 for being in a higher CFS category [95% CI:1.115-1.224]). Overall, cognition worsened in both arms over time (OR=1.007 per week for progression to higher CFS category, 95% CI:1.006-1.008). However, deprescribing mitigated the time trend, and the residents in the deprescribing arm had significantly decreased odds (improved CFS) at 0.996/week (95% CI: 0.995-0.997), 0.900 (95%CI: 0.881-0.919) over 26-weeks, and 0.811 (95% CI: 0.777-0.845) over 52-weeks. Our findings suggest that deprescribing is associated with a slower decline in cognitive function and can help inform future deprescribing interventions for BP management in nursing home residents.

ВПЛИВ ОПТИЧНОГО СКЛА ЯК ПІДКЛАДКИ В ППР-СЕНСОРАХ НА ТЕМПЕРАТУРНУ СТАБІЛЬНІСТЬ РЕЗУЛЬТАТІВ ВИМІРЮВАННЯ

The influence of the properties of the substrate made from optical glass of surface plasmon resonance (SPR) sensors on the temperature stability of measurements at a temperature change from 20 to 30°C, in which research is most often carried out, was studied. The phenomenon of surface plasmon resonance is very sensitive to any changes at the metal-dielectric interface, so studying the influence of the temperature factor is an actual task. Research in the infrared region of the spectrum is important because in this case the possible thickness of the research object increases, and it is also possible to reduce the thickness of the gold layer that is sprayed to the glass substrate of the sensory element from 50 nm to 30 nm. But heating the sensitive element with an IR laser can introduce an additional error into the measurement results. The sensitive element of the SPR device consists of a plate made of optical glass and a thin layer of gold deposited on it. It is known that materials expand when heated. The difference in temperature coefficients of linear expansion of glass and gold applied to it can lead to unequal expansion of glass (74x10 -7 ) and gold (14.2x10 -6 ), respectively, causing elastic stresses in the gold sensitive layer of the sensor. Sensory elements with a 30 nm gold layer are used for the IR range of measurements, and 50 nm for the visible range. Therefore, we investigated the stability of the results of measuring the angle of surface plasmon resonance minimum at a wavelength of 650 nm (Plasmon-6 device). It was determined that the optical glass of the substrate affects the stability of measurements of the SPR index of air from temperature fluctuations. The period of stabilization of measurement results in the visible range when the temperature changes from 20 to 30 °C to the change in the angle of the SPR minimum changes from 0.0006 degrees/min for Zerodur to 0.0032 degrees/min for flints, i.e. almost 5 times with the thickness of the gold nanolayer 50 nm, and for a thickness of 30 nm it varies from 0.0010 deg/min for crowns and quartz to 0.0013 deg/min for flints. The lowest value corresponds to Zerodur substrates with practically zero temperature coefficient of linear expansion and quartz in this temperature range. To ensure the stability of the results of measurements of SPR characteristics against temperature fluctuations in the range of 20-30°С, it is recommended to use Zerodur, quartz and crowns for the substrates of SPR sensors

MODULATION OF MITOCHONDRIAL THIOREDOXIN IN AGE-RELATE MUSCLE ATROPHY AND INJURY

Abstract Maintenance of skeletal muscle is vital to health and wellbeing. Over the course of age there is a progressive decline in muscle mass and function. This decline results in frailty, reduced independence, reduced quality of life and elevated risk of mortality. Lean muscle mass contributes approximately 50% of body mass in a young adult while only 25% in an individual in their 80s. Critically, this decline in muscle mass is not continuous but composed of periods of stability punctuated by rapid declines. The chief driver of such events is loss due to injury related inactivity. Bed rest, is an essential part of recovering from injuries, however, long periods of inactivity can lead to skeletal muscle atrophy. A study of just 10 days bed rest in older adults produced a 6% decline in lower extremity lean muscle mass and a 15% decline in muscle function. Importantly much of the muscle mass lost even from short bed rest events are thought to never be recovered and to accelerate age related muscle declines. For this reason, development of interventions which reduce bed rest induced muscular atrophy would have considerable benefits in maintenance of independence for older adults. In my research project I am investigating a novel genetic target to ameliorate muscle atrophy as a consequence of immobility. We have found the protein TXNIP, a critical driver of apoptosis, to be induced under limb. Using TXNIP knockdown and TXNIP inhibitors I’m testing the hypothesis that prevention of TXNIP induction can reduce muscle atrophy.

Achieving ultra-high nitrogen and phosphorus removal from real municipal wastewater in a novel continuous-flow anaerobic/aerobic/anoxic process via partial nitrification, endogenous denitrification and nitrite-type denitrifying phosphorus removal

Achieving economic and efficient removal of nutrients in mainstream wastewater treatment plants (WWTPs) continues to be a challenging research topic. In this study, a continuous-flow anaerobic/aerobic/anoxic system with sludge double recirculation (AOA-SDR), which integrated partial nitrification (PN), endogenous denitrification (ED) and nitrite-type denitrifying phosphorus removal (nDNPR), was constructed to treat real carbon-limited municipal wastewater. The average effluent concentrations of total inorganic nitrogen (TIN) and PO43−-P during the stable operation period were 1.8 and 0.3 mg/L, respectively. PN was achieved with an average nitrite accumulation ratio of 90.4 % by combined strategies. Adequate storage of polyhydroxyalkanoates and glycogen in the anaerobic zone promoted the subsequent nitrogen removal capacity. In the anoxic zone, nitrite served as the main electron acceptor for the denitrifying phosphorus removal process. Mass balance analysis revealed that nDNPR contributed to 23.6 % of TIN removal and 44.7 % of PO43−-P removal. The enrichment of Nitrosomonas (0.45 %) and Ellin 6067 (1.31 %), along with the washout of Nitrospira (0.15 %) provided the bacterial basis for the successful implementation of PN. Other dominant endogenous heterotrophic bacteria, such as Dechlormonas (10.81 %) and Candidatus Accumulibacter (2.96 %), ensured simultaneous nitrogen and phosphorus removal performance. The successful validation of integrating PN, ED and nDNPR for advanced nutrient removal in the AOA-SDR process provides a transformative technology for WWTPs.

An Advanced Early-Stage Production Forecasting Model for Middle-High Rank Coal Development

Reasonable production prediction of coalbed methane (CBM) is of great significance for improving the economic benefit of CBM reservoirs. Current prediction methods for CBM production focus on the later stages of development, with few studies on early production forecasting. The objective of this work is to provide a reliable new idea for the early production prediction of CBM through various analyses and demonstrations. First, the CBM development modes are classified according to the production characteristics of the Panhe demonstration block of Shaanxi Province, China. Second, an efficient and feasible early production prediction model is established based on the geological potential and development potential. Finally, using the proposed model, different modes’ production characteristics and optimization strategies are analyzed. The research shows that the gas production profiles can be divided into two modes: single-peak mode (SPM) and multipeak mode (MPM). The peak production and average EUR of the SPM are 49.6% and 32.4% higher than those of the MPM, but the stable production period is only 0.2~1 year. In terms of the geological potential of CBM wells, the gas content, critical desorption pressure, and formation coefficient of the SPM are 6.7%, 13.3%, and 37.8% higher than those of the MPM, and the gas wells are mainly located in the high part of the coal seam (the average height difference is about 20 m). Besides, the concept of quasidesorption degree Pdq is innovatively introduced to characterize the development potential of gas well. The Pdq has an exponential relationship with CBM production, and the coefficient of the exponential term in SPM is approximately 22% larger than that in MPM. Moreover, the production of gas wells is greatly affected by the continuity of production. In the process of gas production, the influence of factors such as equipment shutdown should be minimized. To examine the applicability of the proposed method, the model is applied to an actual CBM well in Panhe, and the prediction accuracy is higher than 85%.

Application of a new anionic surfactant based on sesame oil by Alkali-Surfactant (AS) injection in chemical enhanced oil Recovery: Characterization, mechanisms and performance

This study is centered on creating an anionic surfactant using edible sesame oil for enhanced oil recovery (EOR) objects. The surfactant was synthesized under esterification and sulfonation processes. Characterization analyses were performed to describe the surfactant and evaluate its temperature stability. Related experiments were conducted to investigate phase behavior, surface activity, and EOR implications of the surfactant. A chemical flooding experiment was carried out. This involved injecting the surfactant along with the appropriate levels of salinity and alkalinity, into a carbonate plug. Additionally, the ability of the surfactant to generate and maintain foam and emulsion was examined. The surface tension values were reduced from 64 to 33.07 mN/m, and the interfacial tension (IFT) values dropped from 21 to 0.81 mN/m. Through these experiments, the critical micelle concentration (CMC) of the surfactant was determined to be 800 ppm. Upon reaching the CMC, the IFT further decreased to 0.38 and 0.14 mN/m at optimal salinity and alkalinity levels respectively. The previously hydrophobic carbonate surface underwent significant improvement in wettability, transitioning to hydrophilic behavior. This shift was evident as the contact angle decreased from 130.2° to 58.8° within a brief 60-minute equilibration period, representing a suitable wettability state for EOR. The surfactant exhibited an emulsion and foam stability period lasting 35 days. Additionally, its ability to function effectively in the presence of sodium chloride (NaCl) ions was verified with compatibility demonstrated at salinity levels below 100000 ppm. Ultimately, the flooding outcomes displayed a notable 16.18 % enhancement in oil recovery when employing the optimum fluid.

Late-onset, first-ever involuntary movement after successful surgical revascularization for pediatric moyamoya disease – Report of two cases

Background: A small number of children with Moyamoya disease develop involuntary movements as an initial presentation at the onset, which usually resolves after effective surgical revascularization. However, involuntary movements that did not occur at the onset first occur after surgery in very rare cases. In this report, we describe two pediatric cases that developed involuntary movements during the stable postoperative period after successful surgical revascularization. Case Description: A 10-year-old boy developed an ischemic stroke and successfully underwent combined bypass surgery. However, he developed chorea six months later. Another 8-year-old boy developed a transient ischemic attack and successfully underwent combined bypass surgery. However, he developed chorea three years later. In both cases, temporary use of haloperidol was quite effective in resolving the symptoms, and involuntary movements did not recur without any medication during follow-up periods of up to 10 years. Conclusion: Postoperative first-ever involuntary movement is very rare in pediatric moyamoya disease, and the underlying mechanisms are still unclear, but a temporary, reversible imbalance of excitatory and inhibitory circuits in the basal ganglia may trigger the occurrence of these rare symptoms. Careful follow-up would be mandatory.

Evolution and drivers of secondary suspended rivers in typical wandering sections of the lower Yellow River from 1960–2021

The secondary suspended river increases the probability of the occurrence of “Heng river”, “Xie river” and “Gun river” in the lower Yellow River, and is the main factor threatening the safety of human life and property in the Yellow River levee and beach area. Here, the Dongbatou–Gaocun section of the severe secondary suspended river in the lower Yellow River was taken as the research object. The trend and periodicity of the evolution characteristics of the secondary suspended river in the study area from 1960–2021 were systematically analyzed using the Theil-Sen estimator and wavelet analysis, and the factors influencing its development were quantitatively explored. Over the past 62 years, development of secondary suspended rivers can be divided into four stages: initial formation (1960–1973), slow development (1974–1986), rapid development (1987–1999) and stable (2000–2021) periods. The evolution period of the beach transverse gradient differed significantly before and after operation of Xiaolangdi Reservoir commenced, prior to which there was a first main period of 31 years followed by a second main period of 21 years. Development of secondary suspended rivers was primarily related to floodplain flooding and human activity. When the inflow sediment coefficient of a floodplain flood (ζ) was < 0.04 and the floodplain coefficient was < 1.29, the secondary suspended river was relieved; when ζ > 0.04 or ζ < 0.04 and the floodplain coefficient was > 1.29, the secondary suspended river was intensified. The production levees have exacerbated development of secondary suspended rivers to some extent.