bluuebunny/crossref_metadata_2025 huggingface dataset:
Features of aeolian relief formation of the sandy massif Suvinskii Kuitun in the Barguzin Depression
Authors: Vyrkin V B , Kobylkin D V
Published: November 2021

The principal objective of the article is the determination of the main features of the aeolian relief formation of the Suvinskii Kuitun sand massif, one of the regions of active modern aeolian morphogenesis in the Barguzinskaya Depression. A brief description of the morphology of the aeolian relief, characterized by the predominance of deflationary forms over accumulative ones, is given. Among the forms of active deflation, deflation basins dominate here, separated by elongated deflation inselbergs, composed of sands of lacustrine, alluvial, deluvial-proluvial, and aeolian genesis. The mineralogical and granulometric composition of sandy deposits in the southern part of the Suvinskii Kuitun, characterized by poor roundness of sandy grains, has been analysed. A distinct northeastward eolomotion was revealed towards the foothills of the Ikat Range and its accumulation there. The age of the aeolian sands, mainly related to the formation of the Tagar culture (the end of the Bronze Age) was determined. The phytomelioration carried out in the second half of the 20th century led only to a partial fixation of sands, without affecting their overall deflation in most areas of the Suvinskii Kuitun.
Natural and anthropogenic transformation of geosystems of Tunkinsky national park: identification and mapping
Authors: Atutova Zh V
Published: November 2021

The paper focuses on the specifics of landscape medium scale mapping employing traditional methods. We selected a key site in Tunkinsky National Park (Republic of Buryatia) and the Tunkinskaya depression located within it and its mountain framing (south of Eastern Siberia) to display the modern structural and dynamic features of the geosystem functioning. The map compiled at a scale of 1 : 100 000 illustrates the differentiation into categories of landscape structures by types of altitudinal-belt conditions of the natural environment, differing in morphological and phytocenotic properties, as well as the nature of natural-anthropogenic transformation. The main factors of landscape discreteness are morphological features of the surface structure of the intermontane territories; the complexes with natural vegetation and their derivative biocenoses, formed as a result of agricultural and pyrogenic transformation, reflected the dynamic nature of the geosystem functioning. The complexes have been formed in river valleys due to debris flows and are assigned to variable states.
Natural prerequisites and socio-economic factors for the integrated development of lakes as water bodies (on the example of the Republic of Buryatia, Russia)
Authors: Valova E E , Korsunova Ts D-Ts , Baldanov N D
Published: November 2021

The lakes of Buryatia have been studied to varying degrees and described in numerous scientific works by well-known limnologists, geographers and biologists of Russia. The formation of lakes, their composition and the organisms that inhabit them have been investigated. However, very few and sporadic studies have investigated the use of lakes for economic purposes. The article analyses the activities of fisheries, the use of Buryatia’s widespread minerals such as sapropels and peat, and also assesses tourism as an economic activity with a high positive effect for the Republic of Buryatia as a whole.
Quantitative assessment of the health risk, associated with drinking water quality in the Gusinoozersk industrial hub
Authors: Ulzetueva I D , Gomboev B O , Ts-D Zhamyanov D , Khakhinov V V , Gomboeva N B
Published: November 2021

Drinking water, as one of the main components of the habitat, determines human health and quality of life. In the past few decades, almost all water sources, both surface and underground, have been subject to intensive anthropogenic and technogenic impact. Lake Gusinoye, which is the main source of drinking water supply to adjacent settlements, is experiencing significant anthropogenic pressure. Based on the results of hydrochemical studies, the toxic effect of heavy metals on the population health, resulting from the consumption of drinking water of the centralised water supply from Gusinoye Lake, was considered. The results of a quantitative assessment of public health hazards showed that the risk of non-carcinogenic (toxic) effects is high in the territory of the Gusinoozersk industrial hub.
Creating models of integrated development of ecotourism in Russian protected areas
Authors: B-Zh Maksanova L , Kharitonova O B , Andreeva A M
Published: November 2021

The topic of ecotourism is now more relevant than ever, both in Russia and around the world. Despite the existence of well-known world practices of creating a variety of ecotourism products and services compatible with the goals of conservation of natural territories, Russia still has a long way to go to turn ecotourism into alternative form of recreation that contributes to the environmental and socio-economic development in the Russian regions. The article discusses the methodological approaches, experiences, and results of the All-Russian competition organized to identify pilot ecotourism areas, where tourist and recreational clusters (TRCs) may be developed through implementation of the combined potential of nature protection areas and adjacent territories. The research database includes the competition documents and regional projects published on the website https://priroda.life. The paper presents the goals, objectives, stages and features of the competition, regional strategies for participation in the competition, and the best projects. Moreover, the study identifies the key challenges for the development of ecotourism in natural areas. It shows that the process of involving Russian protected areas (PAs) in ecotourism is more than one-step action, that requires a systematic approach to advancement of tourism-and-recreational clusters jointly with the development of natural and adjacent territories.
Natural clays as effective sorbents of anthropogenic pollutants
Authors: Badmaeva S V , Ts Khankhasaeva S , Ukhinova M V
Published: November 2021

In this work, the adsorptive properties the Tuldon deposit were studied using the example of the adsorption of the basic dye “Methyl Green” from aqueous solutions. It has been established that the kinetic regularities of the dye adsorption on clay are consistent with the model of the kinetics of the pseudo-second order, characteristic of chemisorption. The isotherm of the dye adsorption is in good agreement with the Langmuir model. The results of the study allow us to conclude that the clay of the Tuldon deposit can be an effective sorbent for removing basic dyes from aqueous media.
Artemisia of Inner Asia: species diversity, essential oils’ composition and practical use
Authors: Zhigzhitzhapova S V
Published: November 2021

Genus Artemisia is one of the large multispecies genera of the Asteraceae family in the Siberian flora. In the arid and subarid zones of the Holarctic, wormwoods are often the dominant plant community. On the territory of Buryatia there are 47 species of Artemisia, on the territory of Mongolia – 102, and on the Qinghai territory – 54. The genus Artemisia L., growing in Buryatia, Mongolia and Qinghai belongs to three subgenera, of which the subgenus Artemisia is the most widely widespread. The subgenus Seriphidium is more prevalent in Mongolia (16 species), rather than in Buryatia or Qinghai (2 species in each territory). The territories of Buryatia, Mongolia and Qinghai have 13 common species of Artemisia. Among the plants belonging to the genus Artemisia, 40 species grow in both Buryatia and Mongolia at the same time, 22 – in Mongolia and Qinghai, 14 – in Buryatia and Qinghai. The component composition of essential oils is formed as a result of the influence of abiotic and biotic factors of the environment on the plant during its growth. It ensures the best adaptation of the plant to the conditions of particular location. Many species of wormwoods have an important practical value, with a potential to be used in medicine, functional nutrition, food industry, and also as fodder, technical and decorative plants.
Research on Wind Power Prediction Algorithm Based on Fusion Model
Authors: Li Angru , Ma Dechao , Liu Qi , Ji Kun , Ling Shaoliang , Chen Jiajia
Published: November 2021

Wind power generation is currently one of the most promising power generation technologies. It is particularly important to improve the prediction accuracy of wind power output, which can effectively reduce the impact on the grid when wind power is connected to the grid. Based on the fractal model, this paper integrates it with the wind power prediction model, and combines the custom K nearest neighbor algorithm to evaluate the prediction effect using multi-dimensional indicators. Finally, taking the data of a wind farm in northwest china as an example, compared it with the prediction model of random forest, support vector machine and gradient boosting decision tree prediction model to verify the effectiveness of the prediction algorithm in this paper.
The Combustion Numerical Simulation of a Liquid Slag Pulverized Coal Burner in the High Temperature Secondary Air
Authors: Zhao Huaizhi , Wang Jingfu
Published: November 2021

Taking a liquid slag pulverized coal burner as the research object, the combustion characteristics of the burner in different high temperature secondary air were simulated by Fluent commercial software, and the combustion characteristics of temperature field distribution and the change of component concentration were obtained. The simulation results show that the burner can form a front ignition zone, the air vortex low temperature zone, the central DC flame and the annular flame in the hot state. It can be found that increasing the secondary air temperature can improve the combustion intensity of the burner, promote the formation of CO, and form a high temperature reduction zone, which is conducive to inhibiting pollutant emissions. The research results provide theoretical support for the application of the burner in practice.
Analysis of Suspended Potential Discharge Defects by SF6 Decomposition Products
Authors: Fu Lijun , Guan Yanling , Zhang Liang , Zhang Jian
Published: November 2021

The type and content of SF6 decomposition products are directly related to the type, location and degree of fault. Based on the analysis of the abnormal SF6 gas decomposition product content and discharge type of 126kV Porcelain Column type circuit breaker, the potential fault of the circuit breaker is judged to be suspension potential discharge fault. After disassembling the circuit breaker, it is found that the abnormal phase of the insulation rod is deformed, the pin become thin, and there are solid decomposition products, the sulfides and fluoride, which are mainly composed of iron, aluminum, chromium and manganese, further confirm that the potential fault of the circuit breaker is suspension potential discharge fault. The forming process and reaction mechanism of the suspended potential discharge fault are analyzed. Once the fault occurs, its function will promote the development of the fault. The influence of the suspension potential discharge fault on the performance of the circuit breaker is also analyzed. When the suspension potential discharge fault exists, it will cause the abnormality and even affect the normal operation of the circuit breake.
Effect of Unbalanced Force Loading on the Safety of Transmission Tower
Authors: Zhang Hongji
Published: November 2021

High-voltage transmission towers, as support points for overhead transmission lines, are often under the condition of unbalanced force loading. Transmission towers can collapse because of the unbalanced forces, leading to the power outage. Therefore, it is of practical importance to set a research on the effect of unbalanced force loading on the safety of transmission tower. In this paper, based on the prototype of 500kV transmission tower, the integral beam element model is established by ABAQUS finite element software for simulation analysis. Static load mode and unbalanced force loading were considered in this simulation model. Through the comparative analysis of the maximum displacement and stress in transmission tower, the safety of the 500kV transmission tower was analyzed. The variations of maximum displacement and Mises stress with the increasing unbalanced force were obtained. The limit of unbalanced force the 500kV transmission tower can sustain was given by comparing the simulated results.
Research on Micro-terrain Classification of Transmission Line Galloping
Authors: Li Li , Xu Xunjian , Guo Jun , Jian Zhou
Published: November 2021

Micro-terrain and micro-weather have an important impact on transmission line galloping. In order to carry out galloping prediction of micro-terrain, the classification of galloping micro-terrain is studied in this work. Firstly, we collect historical data of 1537 galloping points from the State Grid Corporation of China, and select 208 galloping points located in the micro-terrain area by analyzing the altitude and the topographic relief characteristics around each galloping point. Then the galloping micro-terrain types are extracted by Empirical Orthogonal Function method, the first four spatial modes of galloping micro-terrain are the windward slope of east-west mountain area, the windward slope of north-south mountain area, the independent hill, and the saddle back of mountain/hill. Finally, the regional characteristics of typical micro-terrain are analyzed according to the actual lines.
Influence of Surfactant YB-1 on Core Wettability
Authors: Zheng Yong
Published: November 2021

Based on the core self-priming displacement experiment, the change of self-priming oil displacement and rock wettability of Gemini surfactant in different permeability cores is analyzed. The experimental results show that the self-priming oil displacement of core increases with the decrease of interfacial tension, and the larger the permeability of core is, the more the self-priming oil displacement is. At the same time, the wettability of core changes from lipophilic to hydrophilic. It is found that the relationship between the interfacial tension and the moisture index is logarithmic.
Analysis and Study on the Degradation of Sarfloxacin Hydrochloride by BiVO4 Synthetic Material
Authors: Zhang Yue , Liu Wenbin , Yu Liansheng , Lv Kuilin , Lv Yuguang
Published: November 2021

Difloxacin hydrochloride is commonly used in livestock and poultry chronic respiratory diseases, tracheitis, enteritis, pneumonia, avian cholera, Streptococcosis, typhoid and other diseases caused by sensitive bacteria such as Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Proteus and Pasteurella multocida, especially for Chicken Colibacillosis, piglet red, yellow and white dysentery. The prepared BiVO4 synthetic material was used for photodegradation of the target degradation product of salfloxacin hydrochloride. The degradation rate of the sample to salfloxacin hydrochloride was 24.1%; The degradation rate of the composite sample (Polypyrrole/graphene oxide/bismuth vanadate) reached 75.57%. The degradation rate was 5 times that of BiVO4.
High-rise Building Integrated with Solar Chimney and Bioenergy
Authors: Wang Biao , Wang Zhihao
Published: November 2021

In dense mega cities, high-rise buildings huge energy consumption on mechanical ventilation and overheat produced by the air conditioners are among big challenges for the sustainable building development and green city construction. Solar chimney is proved to be an efficient method to promote natural ventilation for buildings. Different types of solar chimney are presented with a high-rise building layout example. Solar chimney geometry and environment basic data is suggested to be evaluated to optimize the Solar chimney’s natural ventilation. In addition, aiming as well a clean and sustainable environment, bio-energy can be adopted in buildings by integrating with algae-fluid window and wall system. Different materials of radiation absorber can be studied and integrated with solar chimney. An outline of research on solar chimney integrated with bio-energy for high-rise building is given in this paper. In order to succeed, close multidisciplinary cooperation is necessary for the project which involves at least architecture, thermal physics, air dynamics, materials science and biology. Experiment conditions and potential risk should be discussed beforehand.
Investigation on the use of aluminium rich sandy soil as natural adsorbent in the removal of lead from water
Authors: Ng Y S , Tan Y J , Heng K J , Ong Y H
Published: November 2021

The feasibility of aluminium rich sandy soil collected from Jeram as natural adsorbent in removing lead (Pb) from water was investigated without any surface modification. The investigation on the effect of initial concentration, solution pH, and soil:solution ratio was carried out using response surface methodology. The adsorption efficiency was increased at higher pH and soil:solution ratio, as well as lower initial concentration, as a result of higher availability of adsorption sites and less adsorbate competition. The adsorption followed Langmuir isotherm and monolayer chemisorption with an adsorption capacity of 10.64 mg g−1. The process followed pseudo-second order kinetic model, with a rate constant of 0.011 g mg−1min−1at optimum adsorption pH of 4-5.
Impact of heavy hydrocarbon impurities on polytetrafluoroethylene (PTFE) membrane stability
Authors: Saleh S M , Chan Z P , Chang F F A C
Published: November 2021

Membrane contactor technology has attained considerable attention as a promising technology to reduce CO2 content in natural gas. In this study, the main objective is to investigate the effect of heavy hydrocarbons impurities, often present in natural gas, on polytetrafluoroethylene (PTFE) hollow fibre membrane. The membranes were immersed for months in n-heptane, 1-decene, benzene and toluene, and analysed periodically through its surface morphology, composition, functional groups, hydrophobicity, and thermal stability. The characteristics of PTFE fibres remained unchanged even after long term exposure with heavy hydrocarbons. This study provides a better understanding of the robustness of using PTFE membrane fibre for CO2 removal in membrane contactor system.
Synthesis of symmetrical structured triglycerides via a bottom-up process
Authors: Agapay R C , Go A W , Ju Y H
Published: November 2021

The synthesis of symmetrical structured triglycerides (STG) through a bottom-up approach was previously shown to produce 1,3-dioleoyl-2-palmitoyl glycerol in significant quantities. This solvent-free lipase-catalyzed process, consisting of a low-temperature (40 °C) esterification step with glycerol dosing followed by a high-temperature (60 °C) esterification step, was further investigated in the production of symmetrical medium-and-long-chain triglycerides (MLCT). By replacing oleic acid with capric acid in the first step or the palmitic acid by either capric acid or lauric acid in the second step, the effects of free fatty chain length and sequence of fatty acid addition on STG production were established. These produced 1,3-dicaproyl-2-oleoyl glycerol, 1,3-dioleoyl-2-caproyl glycerol, and 1,3-dioleoyl-2-lauroyl glycerol at concentrations of 36.98 g, 36.77 g, and 37.08 g per 100 g of triglycerides respectively after 72 h at an overall FFA1:FFA2:Glycerol of 2:1:1 and 4 g Novozyme 435 per 100 g reactants, without the purification of intermediates and products. The sequence of fatty acid addition had the most significant effect as purer STG products can be obtained when the medium chain fatty acid is introduced in the first step. As the process was carried out without solvents, the STG produced are appropriate for functional food or nutraceutical applications.
Organic acid-assisted catalytic wet torrefaction of oil palm trunks (OPT)
Authors: Soh M , Chew J J , Sunarso J
Published: November 2021

Oil palm trunks (OPT) are attractive bio-fuel sources given their abundant availability. Nonetheless, the inherent properties of these biomass can lead to their inefficient use as bio-fuel directly. This work utilizes four organic acids (i.e., acetic, formic, levulinic, and citric acid) as catalyst in wet torrefaction to enhance the fuel properties of OPT hydrochar. In this study, the effects of different catalysts, catalyst concentrations, and residence times on the fuel properties of OPT hydrochar are analyzed. To study the effect of residence time, 0.2M of acid concentration was used for all four acids at 220 °C for 3 hr and 24 hr. Meanwhile, study on the effect of catalyst concentration was performed at 220 °C for 24 hr at 0.2M and 1.0M for all four acids. Increasing the residence time decreased the solid yield of OPT hydrochar treated in deionized water, acetic, formic, and levulinic acid, while wet torrefaction in citric acid results in close solid yield value in both residence time. The energy yield was observed to decrease in all liquid medium with increasing residence time except for formic acid and citric acid. On the other hand, increasing the acid concentration increased the OPT hydrochar solid yield in all acids except formic acid and the highest energy yield of 77.08% was obtained from wet torrefaction in 1.0M of citric acid at 220 °C for 24 hr. In summary, citric acid is an environmentally friendly acid to be used as catalyst to enhance the fuel properties of OPT hydrochar. Further study on the reaction mechanisms that governs such fuel properties enhancement with citric acid is warranted.
Extraction of magnesium from salt pond waste with low lithium grade using sodium silicate reagent
Authors: Sulistiyono E , Harjanto S , Lalasari L H
Published: November 2021

Nowadays, Indonesia’s salt production process has shifted from a traditional salt pond process to a salt pond with a geomembrane tarpaulin system. This system has the advantage of producing a faster salting process and a better salt quality and producing a thick yellow liquid waste known as bittern. The waste produced has not been fully utilized, even though the waste contains valuable elements, namely magnesium, lithium, and others. This paper investigates the potential utilization of bittern by extracting magnesium from by-product salt pond using sodium silicate reagent with various concentrations of 125–250 g/l. The bittern used in this experiment had the chemical composition as follows: 33,184 ppm magnesium (Mg), 23,787 ppm sodium (Na), 6.1 ppm lithium (Li), 5,491 ppm potassium (K), 617 ppm calcium (Ca), 152 ppm boron (B). The highest removal of magnesium ion by addition of sodium silicate of 250 g/l was about 96.2%. The results showed that the solid products were magnesium silicate precipitates without containing asbestos compounds. The magnesium silicate precipitate product can be applied as talc raw material for the pharmaceutical industry.
Fractionation of phycocyanin and carbohydrate from Spirulina platensis using ionic liquid-based aqueous two-phase system
Authors: Choi Y H , Mah S K , Ng Y S , Lee S Y
Published: November 2021

Microalgae have gained considerable attention due to their high-value biomolecules and potential applications in the pharmaceutical, food, medical and cosmeceutical field. However, the conventional biorefinery process of microalgae are costly, energy-intensive, and time-consuming. Aqueous two-phase system (ATPS) has emerged as a potential technique for the separation and fractionation of biomolecules in the biorefinery field. This study proposed the application of ionic liquid (IL) based ATPS for the fractionation of high-value phycocyanin and carbohydrates from a crude extract of Spirulina platensis.The biomass was first lysed by a high-speed homogenization with a solid to liquid ratio (S/L) of 1:10 and an operation time of 5 min to achieve optimum yields of multiple products. Next, the feasibility of several IL-based ATPS with phosphate/citrate buffer was evaluated by investigating the effects of cation, anion, and alkyl chain’s length of ILs. Among the IL-based ATPS, the system comprising of 1-butyl-1-methylpyrrolidinium dicyanamide and citrate buffer demonstrated the optimum phycocyanin extraction efficiency of 83.26 ± 0.05% at the top phase and a concurrent recovery of 73.89±0.06% carbohydrate at the bottom phase. In this work, the IL-based ATPS performed better than conventional polymer-based ATPS. This work suggests that IL-based ATPS allows efficient fractionation of phycocyanin and carbohydrates.
Chitosan-TiO2 nanotubes scaffolds for proliferation and early differentiation of MG63 by functionalization with fetal bovine serum
Authors: Lim S S , Zu H M , Loh H S
Published: November 2021

Scaffolds have been used as alternative biomaterials to overcome physiological bone disorders. Production of scaffolds has been challenging to fulfil the following criteria: biodegradability, mechanical sustainability, and biocompatibility. For cellular interaction, protein adsorbed on scaffold surface is important for osteoblastic activities. This study aimed to functionalize chitosan-TiO2 nanotubes scaffolds with fetal bovine serum and investigate in vitro efficacy of such scaffolds with fetal bovine serum. Chitosan-TiO2 nanotubes scaffolds were prepared via direct blending and lyophilization. They were then functionalized with fetal bovine serum via adsorption for 4, 8, 12 and 24 h. The in vitro efficacy of the functionalized scaffolds was evaluated using MG63 cells. The adsorption of fetal bovine serum onto the scaffolds was complex where saturation of adsorption was hardly attained. The in vitro efficacy of scaffolds with adsorbed fetal bovine serum was higher than that of those without fetal bovine serum by promoting better osteoblastic functions. Notably, the scaffolds functionalized for 4 h enhanced cell adhesion and proliferation on 7 day suggesting good regulation of osteoblastic binding and proliferation. ALP protein was expressed on 26 day in all functionalized scaffolds. Chitosan-TiO2 nanotubes scaffolds with adsorbed fetal bovine serum can be a potential regenerative material for bone regeneration.
Evolution of predictive emissions in PETRONAS
Authors: Rusman A , Tuan Mat TA , Shabudin N
Published: November 2021

The effect of global warming and unprecedented black swan events give rise to innovative solutions to keep manufacturing companies stay afloat. Many countries have started to employ more stringent emissions limits and stricter monitoring enforcements. PETRONAS is not spared from these policies and with the enforcement of Clean Air Regulation Act (CAR) 2014, PETRONAS embarked on its emissions monitoring via statistical modelling methods. Traditional analysers are still employed for the emissions monitoring, but the focus of the paper is to spotlight the efforts in utilising soft sensors in ensuring compliance to CAR 2014. Soft sensors are predictive models developed to infer primary parameters. The models can be derived via statistical tools or based on first principles using chemical engineering knowledge. The use of soft sensors is not only pervasive in the manufacturing industry but is also widely used elsewhere as it provides an indication of the future position of the primary indicators for the specific industry. The paper will also provide some insights on potential next steps in supporting PETRONAS efforts in its Sustainability Agenda. It also tells the story of collaborative efforts in maintaining good positive governance and relationship with its stakeholders.
Optimising of vacuum distillation units using surrogate models
Authors: H’ng S X , Ng L Y , Ng D K S , Andiappan V
Published: November 2021

Crude oil blending is an important step for the operation of crude distillation systems in the refinery to improve the yield and profitability of the products. The product’s yield and quality are strongly dependent on the properties of the crude oil. However, the products of crude distillation units, especially the vacuum distillation unit (VDU) need to satisfy the yield and quality requirements of the downstream process units in the refinery. Otherwise, the performance of downstream processes will be affected, and loss of profitability in the refinery. Hence, it is important to optimise the performance of the VDU to ensure the optimum operation of VDU. This work covers the process simulation of VDU, surrogate modelling and mathematical optimisation model. The objective of the developed optimisation model is to determine an optimal for maximum high vacuum gas oil (HVGO) yield and minimum total annualised cost (TAC) respectively. To do this, crude oil blending ratio, column temperature, column pressure, stripping steam flowrate, pump-around flowrate in the VDU are optimised. Based on the optimised result, the heavy-light crude blend achieves higher HVGO yield and lower TAC as compared to the heavy-medium crude blend and heavy-medium-light crude blend. The optimised results can provide insight into the optimal process conditions of VDU for the refiners. With this insight, effective operating strategies can be developed to overcome the limitations present in real VDU operations.
Utilization of supercritical carbon dioxide (SC-CO2) in lipids extraction from sewage sludge cake: A preliminary study
Authors: Khalil N A , Hamid H A , Fizal A N S , Zulkifli M , Hossain M S , Yahaya A N A
Published: November 2021

Sewage sludge containing a large number of lipids that can be recovered and utilised as a promising raw material in the production of biodiesel. Studies have been conducted to extract lipids from sludge using conventional solvent methods. However, all these conventional methods have some limitations such as extensive product separation and long extraction time (between 4 to 8 hours), which lead to high energy consumption. Supercritical carbon dioxide extraction (SFE) which utilises carbon dioxide (CO2) gas at its critical condition as solvent has been studied extensively in various fields for oil extraction especially for plant and vegetative. This is due to the shorter extraction time and the lipids can be easily separated from the extraction system. The present research has undertaken a comparison study of supercritical carbon dioxide (SC-CO2) utilisation in the extraction of lipids from sewage sludge against conventional soxhlet extraction of methanol and ethanol as solvent. The extraction of lipids from sewage sludge utilising SC-CO2 extraction was successfully being conducted with lipids yield of 0.69 % within 0.5 hours at the operating temperature of 50 °C and pressure of 20 MPa. The lipids were easily separated subsequently from the SFE system when CO2 is being released in gas form through the outlet valve during lipids collection. Whilst soxhlet extraction using methanol and ethanol as solvent (sludge: solvent ratio of 1:10) managed to extract 1.95 % and 2.81 % within 4 hours of extraction time at 60 °C, with the additional time needed to separate the lipids from solvent by evaporation.
Fundamental study of colloidal stability and dispersion of novel nanosized conductive polyaniline (PANI)/prevulcanised latex (PVL) film for antimicrobial applications
Authors: Banjar M F , Suphi H D , Sarizan M I , Yahaya A N A , Khalil N A , Singh M , Zulkifli M
Published: November 2021

A smart material possessed enhanced conductivity integrated in prevulcanized latex (PVL) film produced throughout this work. Also recognizing the synthesis route of PANI was vast and vary, choosing suitable method was great importance corresponding to the aim of study. PANI was prepared through chemical oxidative polymerization of aniline carried out in aqueous solution which aniline dissolved in strong acidic solution (1 M HCl) with the presence of Ammonium Persulphate (APS) as the oxidizing agent and Sodium Dodecyl Sulphate (SDS) as surfactant. However, PANI was readily in acidic condition while PVL in basic and consequently causes a state of immiscibility upon mixing. Hence, PANI formed then mixed with 0.1 – 0.5 % KOH via homogenizer to increase the pH and maintain the homogeneity as well as dispersion to be combined with PVL. Various studies on PANI synthesis and incorporation with latex had been reported but very limited in focusing the colloidal and dispersion stability of the mixture. Zeta potential measurements revealed an effective dispersion and the colloidal stability as the pH of PANI increases. Analysis of mechanical performance using Universal testing Machine revealed that addition of PANI improves greatly in novel film tensile strength and Young’s Modulus by 109 % and 230 %, respectively.
Influence of anode temperature on ignition performance of the IRIT4-2D iodine-fueled radio frequency ion thruster
Authors: ZHANG Xinghua , ZHANG Zhenhua , JIA Shaoxia , JIN Ting , YANG Jinghua , LI Long , LIU Fangfang , CAI Yong , CAI Jian
Published: November 2021

This paper reports the ignition performance of the iodine-fueled radio frequency (RF) ion thruster (IRIT) at different anode temperatures (

T

a0

). The experimental results show that the anode temperature plays important role on the ignition process of the IRIT. There were two characteristic temperatures related to the anode: the minimum ignition temperature (

T

i0

) and the stable ignition temperature (

T

is

), which were much lower than the pipeline temperature and the storage tank temperature. At

T

a0

< 

T

i0

,

it failed to discharge. When

T

i0

 ≤ 

T

a0

<

T

is

,

it was ignited with dramatical oscillations. At

T

a0

 ≥ 

T

is

,

the discharge was stable in a large anode temperature range. The analysis showed that the different discharge phenomena at different anode temperatures were attributed to the change of iodine flow rate during the process of the iodine deposition-clogging and sublimation-clearing inside the thruster. The research helps improve the preheating design of the iodine-fueled electric thruster.
Thermoelectric efficiency of anisotropic materials with an application in layered systems
Authors: Shi Wencong , Woods Lilia M
Published: November 2021

Thermoelectric (TE) transport in anisotropic materials is investigated based on most general thermodynamical concepts. Currents and power conversion efficiency are studied in SnSe and SnS in different directions. The design of composites whose TE performance along different principles directions is the same is proposed. Although such features do not occur naturally, such man-made anisotropic materials can be constructed using bilayers achieving much broadened working conditions of TE conversion devices. Intricate relationships between the anisotropy and the direction of the electric and heat currents are revealed, which further help us understand how transport occurs in such composites.
Quality improvement and reconciliation process for automated dispensing cabinet medication overrides
Authors: Rhodes James A M , Bondi Deborah S , Celmins Laura , Hope Charlene , Knoebel Randall W
Published: November 2021

Purpose

To describe a pharmacist-led reconciliation process for automated dispensing cabinet (ADC) medication override setting maintenance at an academic medical center.

ADC override management requires alignment of people, processes, and technology. This evaluation describes system-wide improvements to enhance institutional medication override policy compliance by establishing a formalized evaluation and defined roles to streamline ADC dispense setting management. A pharmacist-led quality improvement initiative revised the institutional medication override list to improve medication dispensing practices across an academic medical center campus with a pediatric hospital and 2 adult hospitals. This initiative included removal of patient care unit designations from the medication override list, revision of institutional override policy, creation of an online submission form, and selection of ADC override metrics for surveillance. A conceptual framework guided decisions for unique dosage forms and interdisciplinary engagement. Employing this framework revised workflows for stakeholders in the medication-use process through clinical pharmacist evaluation, existing shared governance structure communication, and pharmacy automation support.

The revised policy increased the number of medications available for override from 80 to 106 (33% increase) and unique dosage forms from 166 to 191 (15% increase). The total number of medication dispense settings was reduced from 5,600 to 541 (90% decrease). The proportion of override dispenses compliant with policy increased from 59% to 98% (P < 0.001). Median monthly ADC overrides remained unchanged following policy revision (P = 0.995). ADC override rate reduction was observed across the institution, with the rate decreasing from 1.4% to 1.2% (P < 0.001). Similar ADC override rate reductions were observed for adult, pediatric, and emergency department ADCs.

Conclusion

This initiative highlights pharmacists’ role in leading institutional policy changes that influence the medication-use process through ADC dispensing practices. A pharmacist-led reconciliation process that removed practice area designations from our medication override policy streamlined ADC setting maintenance, increased the compliance rate of ADC override transactions, and provided a formalized process for future evaluation of medication overrides.
Impact of Variability in Job Coding on Reliability in Exposure Estimates Obtained via a Job-Exposure Matrix
Authors: Rémen Thomas , Richardson Lesley , Siemiatycki Jack , Lavoué Jérôme
Published: November 2021

Objectives

The use of a job-exposure matrix (JEM) to assess exposure to potential health hazards in occupational epidemiological studies requires coding each participant’s job history to a standard occupation and/or industry classification system recognized by the JEM. The objectives of this study were to assess the impact of inter-coder variability in job coding on reliability in exposure estimates derived from linking the job codes to the Canadian job-exposure matrix (CANJEM) and to identify influent parameters.

Method

Two trained coders independently coded 1000 jobs sampled from a population-based case–control study to the ISCO-1968 occupation classification at the five-digit resolution level, of which 859 could be linked to CANJEM using both assigned codes. Each of the two sets of codes was separately linked to CANJEM and thereby generated, for each of the 258 occupational agents available in CANJEM, two exposure estimates: exposure status (yes/no) and intensity of exposure (low, medium, and high) for exposed jobs only. Then, inter-rater reliability (IRR) was computed (i) after stratifying agents in 4 classes depending, for each, on the proportion of occupation codes in CANJEM defined as ‘exposed’ and (ii) for two additional scenarios restricted to jobs coded differently: the first one using experts’ codes, the other one using codes randomly selected. IRR was computed using Cohen’s kappa, PABAK and Gwet’s AC1 index for exposure status, and weighted kappa and Gwet’s AC2 for exposure intensity.

Results

Across all agents and based on all jobs, median (Q1, Q3; Nagents) values were 0.68 (0.59, 0.75; 220) for kappa, 0.99 (0.95, 1.00; 258) for PABAK, and 0.99 (0.97, 1.00; 258) for AC1. For the additional scenarios, median kappa was 0.28 (0.00, 0.45; 209) and −0.01 (−0.02, 00; 233) restricted to jobs coded differently using experts’ and random codes, respectively. A similar decreasing pattern was observed for PABAK and AC1 albeit with higher absolute values. Median kappa remained stable across exposure prevalence classes but was more variable for low prevalent agents. PABAK and AC1 decreased with increasing prevalence. Considering exposure intensity and all exposed jobs, median values were 0.79 (0.68, 0.91; 96) for weighted kappa, and 0.95 (0.89, 0.99; 102) for AC2. For the additional scenarios, median kappa was, respectively, 0.28 (−0.04, 0.42) and −0.05 (−0.18, 0.09) restricted to jobs coded differently using experts’ and random codes, with a similar though attenuated pattern for AC2.

Conclusion

Despite reassuring overall reliability results, our study clearly demonstrated the loss of information associated with jobs coded differently. Especially, in cases of low exposure prevalence, efforts should be made to reliably code potentially exposed jobs.
Nesfatin-1 inhibits free fatty acid (FFA)-induced endothelial inflammation via Gfi1/NF-κB signaling
Authors: Meng Qingtao , Lu Qin , Zhang Zhipeng , Liu Jiyi , Lou Yu , Wang Yuwei , Liu Jihong
Published: November 2021

Nesfatin-1 is a neuropeptide produced in the hypothalamus. It is known that Nesfatin-1 is involved in food uptake, fat storage, and other metabolic regulation. We hypothesized that Nesfatin-1 may play a role in cardiovascular tissue. Free fatty acids (FFAs) are known to be the risk factor for cardiovascular diseases. FFA-mediated endothelial dysfunction is the critical mechanism of many cardiovascular disorders. The present study explores the protective effects of Nesfatin-1 on FFA-induced endothelial inflammation and the underlying mechanism. We found that significantly increased lactate dehydrogenase release and production of inflammatory factors were observed in FFA-treated human aortic endothelial cells (HAECs), accompanied by the enhanced attachment of U937 monocytes to HAECs and upregulated cell adhesion molecule vascular cell adhesion molecule-1, which were dramatically reversed by the treatment with Nesfatin-1. In addition, the promoted level of nuclear regulator NF-κB p65 and transcriptional function of NF-κB in FFA-treated HAECs were greatly suppressed by HAECs. Growth Factor Independent 1 Transcriptional Repressor 1 (Gfi1), an important negative regulator of NF-κB activity, was significantly downregulated in HAECs by FFAs and was upregulated by Nesfatin-1. Lastly, the inhibitory effects of Nesfatin-1 against FFA-induced NF-κB activation and adhesion of U937 monocytes to HAECs were abolished by the knockdown of Gfi1. In conclusion, our data reveal that Nesfatin-1 inhibited FFA-induced endothelial inflammation mediated by the Gfi1/NF-κB signaling pathway.
Structural equation modeling reveals determinants of fitness in a cooperatively breeding bird
Authors: Busana Michela , Weissing Franz J , Hammers Martijn , Bakker Joke , Dugdale Hannah L , Raj Pant Sara , Richardson David S , Burke Terrence A , Komdeur Jan
Published: November 2021

Even in well-studied organisms, it is often challenging to uncover the social and environmental determinants of fitness. Typically, fitness is determined by a variety of factors that act in concert, thus forming complex networks of causal relationships. Moreover, even strong correlations between social and environmental conditions and fitness components may not be indicative of direct causal links, as the measured variables may be driven by unmeasured (or unmeasurable) causal factors. Standard statistical approaches, like multiple regression analyses, are not suited for disentangling such complex causal relationships. Here, we apply structural equation modeling (SEM), a technique that is specifically designed to reveal causal relationships between variables, and which also allows to include hypothetical causal factors. Therefore, SEM seems ideally suited for comparing alternative hypotheses on how fitness differences arise from differences in social and environmental factors. We apply SEM to a rich data set collected in a long-term study on the Seychelles warbler (Acrocephalus sechellensis), a bird species with facultatively cooperative breeding and a high rate of extra-group paternity. Our analysis reveals that the presence of helpers has a positive effect on the reproductive output of both female and male breeders. In contrast, per capita food availability does not affect reproductive output. Our analysis does not confirm earlier suggestions on other species that the presence of helpers has a negative effect on the reproductive output of male breeders. As such, both female and male breeders should tolerate helpers in their territories, irrespective of food availability.
It’s up to you: The need for self-directed learning for social work students on placement during COVID-19
Authors: Zuchowski Ines , Cleak Helen , Croaker Sandra , Davey Jo-Bentley
Published: November 2021

COVID-19 in 2020 took social work programmes by surprise and for many students an e-placement was offered as the only alternative learning opportunity to complete their placement that year. In this article, we report on a mixed method study with data collected via an online survey with quantitative and qualitative questions exploring students’ experiences in e-placements. Eighty-two students who had undertaken an e-placement responded to the survey that was sent to 1,500 social work students enrolled in twenty-one Australian universities. The results summarise demographic data about the students and a description of the e-placements used, as well as qualitative themes about the students’ experiences and recommendations about e-placements. Four themes were prominent in the qualitative data: ‘opportunities for flexible learning but can be challenging’, ‘learning new skills but missing out on others’, ‘drive your own learning’ and ‘the need for structure, support and connection’. Most students reported that they learnt a range of social work skills, but this required them to take initiative to ensure that learning occurred. The implication for social work education underscores the importance of future proofing social work field education through examining the learning and providing proactive support and clear structures for alternatives to traditional placements.
Oral contraceptives and risk of breast cancer and ovarian cancer in women with a BRCA1 or BRCA2 mutation: a meta-analysis of observational studies
Authors: Park Junli , Huang Dan , Chang Yoon Jung , Lim Myong Cheol , Myung Seung-Kwon
Published: November 2021

It remains inconclusive whether the use of oral contraceptives (OCs) alters the risks of breast or ovarian cancer in women with a breast cancer susceptibility gene 1 (BRCA1) or breast cancer susceptibility gene 2 (BRCA2) mutation. We investigated the association between OC use and the risks of breast or ovarian cancer in this group by using a meta-analysis. PubMed and EMBASE were searched using keywords until February 2021 to identify relevant studies that evaluated the association between OC ever use and the risks of breast or ovarian cancer in women with a BRCA1 or BRCA2 mutation. Twelve studies for breast cancer and eight studies for ovarian cancer were identified. In the random-effects meta-analysis, the ever use of OCs was significantly associated with an increased risk of breast cancer [odds ratio (OR), relative risk (RR) or hazard ratio (HR) = 1.24; 95% confidence interval (CI) 1.08–1.41] and a decreased risk of ovarian cancer (OR/RR/HR = 0.53, 95% CI 0.41–0.67). Consistent findings were observed when BRCA1 and BRCA2 mutation carriers were analyzed separately. The increased risk of breast cancer was observed only in the long-term (>5 years) users of OCs, while the decreased risk of ovarian cancer was observed regardless of the duration of OC use. The current study suggests that the ever use of OCs in BRCA mutation carriers is significantly associated with an increased risk of breast cancer and a decreased risk of ovarian cancer. Therefore, the use of OCs as chemoprevention of ovarian cancer should be cautious in BRCA mutation carriers.