bluuebunny/crossref_metadata_2025 huggingface dataset:
Does Islamic Sustainable Finance Support Sustainable Development Goals to Avert Financial Risk in the Management of Islamic Finance Products? A Critical Literature Review
Authors: Raimi Lukman , Abdur-Rauf Ibrahim Adeniyi , Ashafa Saheed Afolabi
Published: June 2024

Policymakers, governments, and Islamic financial institutions are increasingly focusing on sustainable development, leading to an in-depth examination of current sustainable finance practices, projects, and product portfolios. This study examines the role of Islamic sustainable finance (ISF) in promoting Sustainable Development Goals (SDGs) to avert financial risk in the management of Islamic Finance Products (ISFP). Through qualitative analysis, the study conducts a critical literature review (CLR) that incorporates conceptual, theoretical, and empirical perspectives on ISF and SDGs and addresses two specific research questions. Our study examines over 48 journals from 2010 to 2024 and provides insights into how ISF advances the SDGs across all environmental, social, and economic dimensions. It also highlights that ISF promotes green entrepreneurship by investing in sustainable projects, supporting SMEs, and offering alternative financing. ISF also promotes financial stability, justice, and growth and is consistent with the principles of Maqasid al-Shari’ah. Key ISF mechanisms that promote the SDGs include Islamic Green Sukuk, Socially Responsible Investment Funds, Islamic Microfinance, and Islamic Impact Investing. Integrating Islamic ethical principles into financial activities is crucial for inclusive and sustainable economic development. These qualitative insights are critical for policymakers, Islamic financial institutions, Halal entrepreneurs, environmentalists, and investors to understand the potential of Islamic social finance (ISF) to support sustainable practices, projects, and portfolios. Furthermore, the ISFs alignment with Maqasid al-Shari’ah highlights its importance in promoting sustainable development while mitigating financial risk in ISFPs management. The study offers robust contributions to the existing literature to provide comprehensive insights into how ISF can be effectively used to promote SDGs.
Spatiotemporal Dynamics of Constructed Wetland Landscape Patterns during Rapid Urbanization in Chengdu, China
Authors: Liu Shiliang , Chen Yingying , Yang Rongjie , Li Di , Qiu Yuling , Lu Kezhu , Cao Xinhao , Chen Qibing
Published: June 2024

The degradation of urban ecology, particularly in metropolitan areas distinguished by dense populations and impervious surfaces, presents a worldwide challenge linked to swift urban expansion. Despite extensive documentation of urbanization’s impact on broad regions or specific urban ecosystems over defined time periods, there remains a scarcity of studies investigating the spatiotemporal dynamics of landscape pattern (LP) changes in specific ecosystems at small-to-medium scales within inland megacities as a response to urbanization. Therefore, this work focused on the Bailuwan Wetland Park (BWP) in Chengdu, an inland megacity in southwestern China. Employing satellite imagery data from selected years spanning the previous decade (2010–2021, encompassing 2010, 2012, 2015, 2018, and 2021), this investigation delved into the influences of urbanization on the LP over various time-frames and across different land use/land cover (LULC) types. Our study revealed that urbanization has a significant impact on the patch-/landscape-level characteristics, including the class area (CA), number of patches (NP), patch density (PD), percentage of landscape (PLAND), aggregation index (AI), contagion index (CONTAG), largest patch index (LPI), landscape shape index (LSI), fractal dimension index (FRAC_MN), Shannon’s diversity (SHDI), and evenness index (SHEI). Over the period from 2010 to 2021, NP and PD experienced notable increases, while landscape shape (LSI/FRAC_MN) exhibited greater complexity and fragmentation (PLAND) intensified. Further, landscape heterogeneity (AI/CONTAG) and diversity (SHDI/SHEI) decreased. Particularly significant was the conversion of 52 ha of agricultural land to vegetation, resulting in heightened complexity and fragmentation in vegetation patterns. Additionally, the CA of lakes and rivers decreased following the establishment of the park, while the CA and NP of bare land presented significant increases. These findings suggest that rapid urbanization significantly influences the spatial–temporal dynamics of wetland landscape patterns. Consequently, it is imperative for society to prioritize the restoration and protection of urban constructed wetlands.
Non-Breeding Season Habitat Selection of Three Commonly Occurring Bird Species in a Patchy Habitat in SE China
Authors: Luo Xin , Gao Shuai , Tong Sichun , Cai Yao , Wang Zheng , Li Ning
Published: June 2024

Research into bird habitat selection can unveil the impact of specific habitat characteristics on bird survival. However, empirical information on the environmental factor preferences and differences within the yew ecological garden for birds is still lacking. This study was conducted in a yew ecological garden located in the southern experimental area of the Meihua Mountain National Nature Reserve, Fujian Province, China. We selected three commonly occurring bird species for analysis to discern the factors influencing habitat selection and interspecific differences and the impact of habitat environmental factors. Canopy density and coverage were identified as dominant factors influencing habitat selection for the Red-billed Blue Magpie (Urocissa erythrorhyncha), Black Bulbul (Hypsipetes leucocephalus), and Orange-bellied Leafbird (Chloropsis hardwickii). The height of perching trees, average tree height, and average diameter at breast height were all important determinants for the habitat selection of Red-billed Blue Magpie and Black Bulbul. These dominant factors were consistent with logistic regression analysis results. Both one-way ANOVA and stepwise discriminant analysis revealed significant differences in habitat selection among three commonly occurring bird species. Our results provide important insights into avian habitat selection in patchy habitats, which can be used as a guideline for future conservation and habitat management.
Deciphering Land Use Transitions in Rural China: A Functional Perspective
Authors: Jiang Yanfeng , Wang Tiantian , Xu Yuli
Published: June 2024

Although research on land use transitions has gradually received widespread attention since its introduction to China at the beginning of the new millennium, the lack of a clear portrayal of the transitional characteristics and pathways of land use at the theoretical level has prevented this research from providing adequate support for the regulation and management of rural land use activities. This study aims to bridge this research gap from a functional perspective, since the transition of land system functions—also known as land use functions—heralds the completion of a regional land use transition. The methods employed included a literature review and theoretical analysis. The results show the following: (1) the relationships between land use morphology, land use multifunctionality, and land use functions transition (LUFT) were identified; (2) the connotation of the multifunctional agriculture transition theory was analyzed, and the applicability and limitations of drawing on the theory for researching the transition of land use functions in rural China elucidated; (3) a method for characterizing LUFT is proposed from the “state” and “quality”; (4) a theoretical framework for the LUFT was constructed and anchored in transition theory; and (5) it was summarized that there are three transitional pathways: weak-strong, strong-weak, and dynamic balance. In conclusion, while theories originating from the West can provide references for Chinese research, the significant difference between their socio-economic backgrounds necessitates reconstructing these theories in the light of the actual situation in rural China. The theoretical construction of land use transitions from a functional perspective can more clearly delineate the process, the trend, and the characteristics of the transitions of rural land use, thus offering valuable insights for the regulation and management of land use.
Spatio-Temporal Correlation and Optimization of Urban Development Characteristics and Carbon Balance in Counties: A Case Study of the Anhui Province, China
Authors: Wu Yuling , Kan Hongyun , Deng Aili
Published: June 2024

Exploring the carbon balance pattern from the perspective of urban spatial development pattern is an effective way to solve the urban carbon emissions reduction problem, promote high-quality economic development, and synergize the development of the regional “nature–economy” dual system. Taking 105 counties (districts) in Anhui Province as an example, based on the calculation of regional carbon balance and urban development characteristics in 2001, 2010, and 2019, we used the spatio-temporal leap model to analyze urban development characteristics and combined the GWTR model and geodetic probes to explore the spatial and temporal correlation between the carbon balance and urban development characteristics, as well as their influence mechanisms. The results of the study show that: (1) The carbon balance of the 105 counties in Anhui Province shows a general decline in the time axis, with a small recovery, and the spatial sequence decreases and then increases from the north to the south. (2) The urban structure of southeast Anhui Province and central Anhui Province is stable, and the development status is good, but the carbon balance is out of balance, the carbon emissions are much higher than the carbon sinks, and the urban structure of the mountainous areas of west Anhui Province and north Anhui Province is dynamic and coordinated, with the carbon balance in harmony. (3) The spatial development characteristics of the cities in Anhui Province have a negative impact on the carbon balance at the scale-area level and a positive impact at the functional structure level. Among them, the area of urban built-up area and the number of the largest urban patches have strong explanatory power for the carbon balance, and the number of the largest urban patches is the main driver of spatial heterogeneity in the carbon balance. (4) The carbon budget of Anhui Province under the influence of urban spatial development characteristics can be divided into four regions: the economic development–carbon balance lopsided area, the ecological protection–carbon balance surplus area, the urban agglomeration–carbon balance adjustment area, and the potential enhancement–carbon balance equilibrium area. Based on the results, urban development needs to strengthen the construction of urban functional zones, and when formulating low-carbon policies in provinces with uneven development, it is necessary to comprehensively analyze the differences in development between cities and build cities according to local conditions.
Recent Trends in Landscape Sustainability Research—A Bibliometric Assessment
Authors: Fang Xuening , Kong Lingqiang
Published: June 2024

Landscape sustainability (LS) has received widespread attention from both scientists and practitioners in recent decades. However, a systematic review of the recent trends in this field remains scarce. Here, we present a bibliometric analysis of 715 English papers published in SCI journals (i.e., indexed by Web of Science) during 2006–2023, whose titles, abstracts, or keywords contain both landscape-related terms and sustainability-related terms. Specifically, we quantitatively analyzed the LS literature using a variety of bibliometric methods and qualitatively analyzed the full text of highly cited seminal literature to cross-validate the bibliometric findings. We found that: (1) LS has entered the exponential growth phase (2013–present) after experiencing the incubation phase (pre–2006) and emerging phase (2006–2013). (2) Early LS themes focused on landscape change and the relationship between landscape ecology and sustainability science, while recent LS themes have shifted towards more sectoral topics, such as the relationship between ecosystem services and human well-being, climate change, and urbanization. (3) The closely connected network of cross-citations in seminal literature indicates strong communication among scientists in the field of LS. However, the participatory and solution-oriented research streams of LS have not been well integrated into the core research network of LS. Our results suggest that LS has evolved into a rapidly growing discipline with a stable scientific community and core research themes. To become a well-established discipline, LS needs to further enhance its unique scientific core rather than only drawing knowledge from other related fields. Constructing social–ecological-centered, solution-oriented landscape pattern analysis theory and methods for LS should be a top priority.
Dynamic Binary-Medium Model for Jointed Rock Subjected to Cyclic Loading
Authors: Liu Mingxing , Liu Enlong , Liu Xingyan , Zheng Qingsong
Published: June 2024

Revealing the damage mechanism of jointed rocks under a cyclic loading and formulating the corresponding dynamic constitutive model to meet the requirements for the evaluation of anti-vibration safety for critical engineering construction and operation is an essential, urgent and basic subject. Based on the breakage mechanics for geological material, jointed rock is considered as a binary-medium material composed of the bonded elements and frictional elements. The bonded elements are regarded as elastic-brittle elements, and the frictional elements are regarded as elastic-plastic elements. Firstly, the static binary-medium model for jointed rock is established based on the homogenization method and by introducing the breakage ratio and the strain concentration coefficient. Then, the dynamic binary-medium model for jointed rock under cyclic loads is established considering the nonlinear damage effect resulting from cyclic loads. The breakage ratio formula is improved, and the Drucker–Prager criterion is introduced. During the unloading stage, it is supposed that the breakage ratios and strain concentration coefficients remain unchanged and the stress–strain ratios of both bonded elements and frictional elements are constant. The model is verified by static and dynamic triaxial tests of jointed rock samples with an interpenetrated joint. It is found that the model can describe the nonlinear stress–strain characteristics of a jointed rock subjected to cyclic loads relatively well and can reflect the effects of cyclic loading on the deformation and damage, including the lateral deformation characteristics. Meanwhile, the typical three-stage (varying from sparse to dense to sparse) evolution laws of the stress–strain curves are also reflected relatively well.
Systems of Hemivariational Inclusions with Competing Operators
Authors: Motreanu Dumitru
Published: June 2024

This paper focuses on a system of differential inclusions expressing hemivariational inequalities driven by competing operators constructed with p-Laplacians that involve two real parameters. The existence of a generalized solution is shown by means of an approximation process through approximate solutions in finite dimensional spaces. When the parameters are negative, the generalized solutions become weak solutions. The main novelty of this work is the solvability of systems of differential inclusions for which the ellipticity condition may fail.
An Efficient Iterative Approach for Hermitian Matrices Having a Fourth-Order Convergence Rate to Find the Geometric Mean
Authors: Liu Tao , Li Ting , Ullah Malik Zaka , Alzahrani Abdullah Khamis , Shateyi Stanford
Published: June 2024

The target of this work is to present a multiplication-based iterative method for two Hermitian positive definite matrices to find the geometric mean. The method is constructed via the application of the matrix sign function. It is theoretically investigated that it has fourth order of convergence. The type of convergence is also discussed, which is global under an appropriate choice of the initial matrix. Numerical experiments are reported based on input matrices of different sizes as well as various stopping termination levels with comparisons to methods of the same nature and same number of matrix–matrix multiplications. The simulation results confirm the efficiency of the proposed scheme in contrast to its competitors of the same nature.
Could Insulin Be a Better Regulator of Appetite/Satiety Balance and Body Weight Maintenance in Response to Glucose Exposure Compared to Sucrose Substitutes? Unraveling Current Knowledge and Searching for More Appropriate Choices
Authors: Antasouras Georgios , Dakanalis Antonios , Chrysafi Maria , Papadopoulou Sousana K. , Trifonidi Ioulia , Spanoudaki Maria , Alexatou Olga , Pritsa Agathi , Louka Aikaterini , Giaginis Constantinos
Published: June 2024

Background: Insulin exerts a crucial impact on glucose control, cellular growing, function, and metabolism. It is partially modulated by nutrients, especially as a response to the intake of foods, including carbohydrates. Moreover, insulin can exert an anorexigenic effect when inserted into the hypothalamus of the brain, in which a complex network of an appetite/hunger control system occurs. The current literature review aims at thoroughly summarizing and scrutinizing whether insulin release in response to glucose exposure may be a better choice to control body weight gain and related diseases compared to the use of sucrose substitutes (SSs) in combination with a long-term, well-balanced diet. Methods: This is a comprehensive literature review, which was performed through searching in-depth for the most accurate scientific databases and applying effective and relevant keywords. Results: The insulin action can be inserted into the hypothalamic orexigenic/anorexigenic complex system, activating several anorexigenic peptides, increasing the hedonic aspect of food intake, and effectively controlling the human body weight. In contrast, SSs appear not to affect the orexigenic/anorexigenic complex system, resulting in more cases of uncontrolled body weight maintenance while also increasing the risk of developing related diseases. Conclusions: Most evidence, mainly derived from in vitro and in vivo animal studies, has reinforced the insulin anorexigenic action in the hypothalamus of the brain. Simultaneously, most available clinical studies showed that SSs during a well-balanced diet either maintain or even increase body weight, which may indirectly be ascribed to the fact that they cannot cover the hedonic aspect of food intake. However, there is a strong demand for long-term longitudinal surveys to effectively specify the impact of SSs on human metabolic health.
Research on Atmospheric Corrosion of 45# Steel in Low-Latitude Coastal Areas of China
Authors: Liu Lihong , Zhang Bo , Liu Guoqiang , Wang Liyan , Li Jiao , Yuan Peng , Yang Zi , Feng Zhiyuan
Published: June 2024

Urgent action is required to mitigate the severe corrosion of carbon steel in low-latitude regions. The combination of high humidity, temperature, and salinity in these areas significantly accelerates steel corrosion, posing a substantial threat to the service safety of offshore engineering equipment. This study aims to elucidate the atmospheric corrosion mechanisms of 45# steel in low-latitude coastal areas. Samples of 45# steel were exposed to atmospheric conditions over various durations in the following three geographically distinct regions: Guangzhou, Wanning, and the South China Sea. The corrosion rates were calculated using weight loss tracking and potentiodynamic polarization measurements, while surface corrosion products were examined using X-ray diffraction (XRD) tests. The findings indicate a clear correlation between the corrosion rate of 45# steel and the latitude and specific location of the test area, with the highest to lowest rates observed in the South China Sea, Wanning, and Guangzhou, respectively. Similarly, the extent of corrosion rust penetration in defective coatings followed the same order. Moreover, the protection ability index (PAI) calculations revealed that none of the tested samples formed a protective corrosion film.
Effect of Si Content on Microstructure and Properties of Low-Carbon Medium-Manganese Steel after Intercritical Heat Treatment
Authors: Hu Zihan , Fu Hanguang
Published: June 2024

The microstructure and mechanical properties of three kinds of low-carbon medium-manganese steels with different Si contents under an intercritical heat treatment process were studied. The results show that the microstructure of the test forged steel is mainly composed of ferrite and pearlite. After 900 °C complete austenitizing quenching + 720 °C intercritical quenching, the microstructure of the test steel is mainly composed of ferrite and martensite. With the increase in Si content, the microstructure becomes finer and more uniform. The microstructure of the test steel after 900 °C complete austenitizing quenching + 720 °C intercritical quenching + 680 °C intercritical tempering is dominated by ferrite and tempered martensite, with a small amount of retained austenite and cementite. As the Si content increases, the boundaries between ferrite and tempered martensite become more clear. The tensile strength and hardness of the test steel increase with the increase in Si content, while the elongation first increases and then decreases; the comprehensive performance of the test steel is the best when the Si content is 0.685 wt. %, with a tensile strength of 726 MPa, a yield ratio of only 0.65, the highest elongation of 30.5%, and the highest strong plastic product of 22,143 MPa.%.
EPS Production by Lacticaseibacillus casei Using Glycerol, Glucose, and Molasses as Carbon Sources
Authors: Minari Guilherme Deomedesse , Piazza Rodolfo Debone , Sass Daiane Cristina , Contiero Jonas
Published: June 2024

This study demonstrates that Lactobacillus can produce exopolysaccharides (EPSs) using alternative carbon sources, such as sugarcane molasses and glycerol. After screening 22 strains of Lactobacillus to determine which achieved the highest production of EPS based on dry weight at 37 °C, the strain Ke8 (L. casei) was selected for new experiments. The EPS obtained using glycerol and glucose as carbon sources was classified as a heteropolysaccharide composed of glucose and mannose, containing 1730 g.mol−1, consisting of 39.4% carbohydrates and 18% proteins. The EPS obtained using molasses as the carbon source was characterized as a heteropolysaccharide composed of glucose, galactose, and arabinose, containing 1182 g.mol−1, consisting of 52.9% carbohydrates and 11.69% proteins. This molecule was characterized using Size Exclusion Chromatography (HPLC), Gas chromatography–mass spectrometry (GC-MS), Fourier-transform infrared spectroscopy (FTIR), and proton nuclear magnetic resonance spectroscopy (1H-NMR). The existence of polysaccharides was confirmed via FT-IR and NMR analyses. The results obtained suggest that Lacticaseibacillus casei can grow in media that use alternative carbon sources such as glycerol and molasses. These agro-industry residues are inexpensive, and their use contributes to sustainability. The lack of studies regarding the use of Lacticaseibacillus casei for the production of EPS using renewable carbon sources from agroindustry should be noted.
Chalcogen-Bond-Assisted Formation of the N→C Dative Bonds in the Complexes between Chalcogenadiazoles/Chalcogenatriazoles and Fullerene C60
Authors: Zhang Yu , Wang Weizhou
Published: June 2024

The existence of the N→C dative bonds in the complexes between N-containing molecules and fullerenes have been verified both theoretically and experimentally. However, finding stable N→C dative bonds is still a highly challenging task. In this work, we investigated computationally the N→C dative bonds in the complexes formed by fullerene C60 with 1,2,5-chalcogenadiazoles, 2,1,3-benzochalcogenadiazoles, and 1,2,4,5-chalcogenatriazoles, respectively. It was found that the N→C dative bonds are formed along with the formation of the N–Ch···C (Ch = S, Se, Te) chalcogen bonds. In the gas phase, from S-containing complexes through Se-containing complexes to Te-containing complexes, the intrinsic interaction energies become more and more negative, which indicates that the N–Ch···C chalcogen bonds can facilitate the formation of the N→C dative bonds. The intrinsic interaction energies are compensated by the large deformation energy of fullerene C60. The total interaction energies of Te-containing complexes are negative, while both total interaction energies of the S-containing complexes and Se-containing complexes are positive. This means that the N→C dative bonds in the Te-containing complexes are more easily observed in experiments in comparison with those in the S-containing complexes and Se-containing complexes. This study provides a new theoretical perspective on the experimental observation of the N→C dative bonds in complexes involving fullerenes. Further, the formation of stable N→C dative bonds in the complexes involving fullerenes can significantly change the properties of fullerenes, which will greatly simulate and expand the application range of fullerenes.
An Attempt to Replace Pure Citric Acid with Natural Lemon Juice during Potato Starch Esterification
Authors: Tomaszewska-Ciosk Ewa , Zdybel Ewa , Kapelko-Żeberska Małgorzata , Raszewski Bartosz , Buksa Krzysztof , Maj Agnieszka , Zięba Tomasz , Gryszkin Artur
Published: June 2024

The application of chemical operations in food processing, in which pure chemical compounds are used to modify food ingredients, often raises social concerns. One of the most frequently modified dietary substances is starch, e.g., E1401–E1404, E1412–E1414, E1420, E1422, E1440, E1442, and E1450–E1452. An alternative solution to chemical treatments seems to be the use of raw materials naturally containing substrates applied for starch modification. Heating starch with a lemon juice concentrate can be considered a novel and effective method for producing starch citrate, which is part of the so-called “green chemistry”. The modified preparations obtained as a result of potato starch esterification with natural lemon juice had a comparable degree of esterification to that of the esters produced with pure citric acid. In addition, the use of the juice doubled their resistance to amylolytic enzymes compared to the preparations made with pure acid. Replacing citric acid with lemon juice can facilitate the esterification process, and the analyzed properties of both types of modified preparations indicate that starch esters produced with pure citric acid can be successfully replaced by those produced using natural lemon juice, which may increase the social acceptance of these modified preparations.
Bimetallic Perthiocarbonate Complexes of Cobalt: Synthesis, Structure and Bonding
Authors: Pradhan Alaka Nanda , Mishra Shivankan , Kaur Urminder , Rout Bikram Keshari , Halet Jean-François , Ghosh Sundargopal
Published: June 2024

The syntheses and structural elucidation of bimetallic thiolate complexes of early and late transition metals are described. Thermolysis of the bimetallic hydridoborate species [{Cp*CoPh}{µ-TePh}{µ-TeBH3-ĸ2Te,H}{Cp*Co}] (Cp* = ɳ5-C5Me5) (1) in the presence of CS2 afforded the bimetallic perthiocarbonate complex [(Cp*Co)2(μ-CS4-κ1S:κ2S′)(μ-S2-κ2S″:κ1S‴)] (2) and the dithiolene complex [(Cp*Co)(μ-C3S5-κ1S,S′] (3). Complex 2 contains a four-membered metallaheterocycle (Co2S2) comprising a perthiocarbonate [CS4]2− unit and a disulfide [S2]2− unit, attached opposite to each other. Complex 2 was characterized by employing different multinuclear NMR, infrared spectroscopy, mass spectrometry, and single-crystal X-ray diffraction studies. Preliminary studies show that [Cp*VCl2]3 (4) with an intermediate generated from CS2 and [LiBH4·THF] yielded thiolate species, albeit different from the cobalt system. Furthermore, a computational analysis was performed to provide insight into the bonding of this bimetallic perthiocarbonate complex.
Solvothermal Synthesis of Rare Earth Bisphthalocyanines
Authors: Bolivar-Pineda Lina M. , Mendoza-Domínguez Carlos U. , Rudolf Petra , Basiuk Elena V. , Basiuk Vladimir A.
Published: June 2024

Rare earth bisphthalocyanines (MPc2) are of particular interest because of their behavior as single-molecular magnets, which makes them suitable for applications in molecular spintronics, high-density data storage and quantum computation. Nevertheless, MPc2 are not commercially available, and the synthesis routes are mainly focused on obtaining substituted phthalocyanines. Two preparation routes depend on the precursor: synthesis from phthalonitrile (PN) and the metalation of free or dilithium phthalocyanine (H2Pc and Li2Pc). In both options, byproducts such as free-base phthalocyanine and in the first route additional PN oligomers are generated, which influence the MPc2 yield. There are three preparation methods for these routes: heating, microwave radiation and reflux. In this research, solvothermal synthesis was applied as a new approach to prepare yttrium, lanthanum, gadolinium and terbium unsubstituted bisphthalocyanines using Li2Pc and the rare earth(III) acetylacetonates. Purification by sublimation gave high product yields compared to those reported, namely 68% for YPc2, 43% for LaPc2, 63% for GdPc2 and 62% for TbPc2, without any detectable presence of H2Pc. Characterization by infrared, Raman, ultraviolet–visible and X-ray photoelectron spectroscopy as well as elemental analysis revealed the main featuresof the four bisphthalocyanines, indicating the success of the synthesis of the complexes.
Preparation, Characterization, and Antioxidant Properties of Self-Assembled Nanomicelles of Curcumin-Loaded Amphiphilic Modified Chitosan
Authors: Chen Qizhou , Jiang Yuwei , Yuan Linlan , Liu Lifen , Zhu Xufeng , Chen Rimeng , Wang Zhuo , Wu Kefeng , Luo Hui , Ouyang Qianqian
Published: June 2024

Curcumin (Cur) is a phytochemical with various beneficial properties, including antioxidant, anti-inflammatory, and anticancer activities. However, its hydrophobicity, poor bioavailability, and stability limit its application in many biological approaches. In this study, a novel amphiphilic chitosan wall material was synthesized. The process was carried out via grafting chitosan with succinic anhydride (SA) as a hydrophilic group and deoxycholic acid (DA) as a hydrophobic group; 1H-NMR, FTIR, and XRD were employed to characterize the amphiphilic chitosan (CS—SA—DA). Using a low-cost, inorganic solvent-based procedure, CS—SA—DA was self-assembled to load Cur nanomicelles. This amphiphilic polymer formed self-assembled micelles with a core–shell structure and a critical micelle concentration (CMC) of 0.093 mg·mL−1. Cur-loaded nanomicelles were prepared by self-assembly and characterized by the Nano Particle Size Potential Analyzer and transmission electron microscopy (TEM). The mean particle size of the spherical Cur-loaded micelles was 770 nm. The drug entrapment efficiency and loading capacities were up to 80.80 ± 0.99% and 19.02 ± 0.46%, respectively. The in vitro release profiles of curcumin from micelles showed a constant release of the active drug molecule. Cytotoxicity studies and toxicity tests for zebrafish exhibited the comparable efficacy and safety of this delivery system. Moreover, the results showed that the entrapment of curcumin in micelles improves its stability, antioxidant, and anti-inflammatory activity.
Dispersive Solid Phase Extraction of Melatonin with Graphene/Clay Mixtures and Fluorescence Analysis in Surfactant Aqueous Solutions
Authors: Gutiérrez-Fernández Lucía , Díez-Pascual Ana M. , San Andrés María Paz
Published: June 2024

In this work, the dispersive solid phase extraction (dSPE) of melatonin using graphene (G) mixtures with sepiolite (SEP) and bentonite (BEN) clays as sorbents combined with fluorescence detection has been investigated. The retention was found to be quantitative for both G/SEP and G/BEN 4/96 and 10/90 w/w mixtures. G/clay 4/96 w/w mixtures were selected to study the desorption process since the retention was weaker, thus leading to easier desorption. MeOH and aqueous solutions of the nonionic surfactant Brij L23 were tested as desorbents. For both clays and an initial sample volume of 25 mL, a percentage of melatonin recovery close to 100% was obtained using 10 or 25 mL of MeOH as desorbent. Further, using a G/SEP mixture, 25 mL as the initial sample volume and 5 mL of MeOH or 60 mM Brij L23 solution as the desorbent, recoveries of 98.3% and 90% were attained, respectively. The whole method was applied to herbal tea samples containing melatonin, and the percentage of agreement with the labeled value was 86.5%. It was also applied to herbal samples without melatonin by spiking them with two concentrations of this compound, leading to recoveries of 100 and 102%.
Unique Use of Dibromo–L–Tyrosine Ligand in Building of Cu(II) Coordination Polymer—Experimental and Theoretical Investigations
Authors: Wojciechowska Agnieszka , Janczak Jan , Rojek Tomasz , Ashfaq Muhammad , Malik Magdalena , Trzęsowska Natasza , Wysokiński Rafał , Jezierska Julia
Published: June 2024

Although the crystals of coordination polymer {[CuCl(μ-O,O’-L-Br2Tyr)]}n (1) (L-Br2Tyr = 3,5-dibromo-L-tyrosine) were formed under basic conditions, crystallographic studies revealed that the OH group of the ligand remained protonated. Two adjacent [CuCl(L-Br2Tyr)] monomers, bridged by the carboxylate group of the ligand in the syn-anti bidentate bridging mode, are differently oriented to form a polymeric chain; this specific bridging was detected also by FT-IR and EPR spectroscopy. Each Cu(II) ion in polymeric compound 1 is coordinated in the xy plane by the amino nitrogen and carboxyl oxygen of the parent ligand and the oxygen of the carboxyl group from the symmetry related ligand of the adjacent [Cu(L-Br2Tyr)Cl] monomer, as well as an independent chlorine ion. In addition, the Cu(II) ion in the polymer chain participates in long-distance intermolecular contacts with the oxygen and bromine atoms of the ligands located in the adjacent chains; these intramolecular contacts were also supported by NCI and NBO quantum chemical calculations and Hirshfeld surface analysis. The resulting elongated octahedral geometry based on the [CuCl(L-Br2Tyr)] monomer has a lower than axial symmetry, which is also reflected in the symmetry of the calculated molecular EPR g tensor. Consequently, the components of the d-d band obtained by analysis of the NIR-VIS-UV spectrum were assigned to the corresponding electronic transitions.
Catalytic Differences between Flavohemoglobins of Giardia intestinalis and E. coli
Authors: Hill Sarah , Decorso Isabelle , Nezamololama Novin , Babaei Zahra , Rafferty Steven Patrick
Published: June 2024

The sole known heme enzyme of the parasitic protist Giardia intestinalis is a flavohemoglobin (gFlHb) that acts as a nitric oxide dioxygenase (NOD) and protects the organism from the free radical nitric oxide. To learn more about the properties of this enzyme, we measured its nitric oxide dioxygenase, NADH oxidase, and cytochrome c reductase activities and compared these to the activities of the E. coli flavohemoglobin (Hmp). The turnover number for the NOD activity of gFlHb (23 s−1) is about two-thirds of that of Hmp (34 s−1) at pH 6.5 and 37 °C. The two enzymes differ in their sensitivity towards molecules that act as heme ligands. For both gFlHb and Hmp, inhibition with miconazole, a large imidazole ligand, is adequately described by simple competitive inhibition, with KI = 10 μM and 0.27 μM for gFlHb and Hmp, respectively. Inhibition plots with the small ligand imidazole were biphasic, which is consistent with previous experiments with carbon monoxide as a probe that show that the active site of flavohemoglobins exists in two conformations. Interestingly, the largest difference is observed with nitrite, which, like imidazole, also shows a biphasic inhibition plot; however, nitrite inhibits gFlHb at sub-millimolar concentrations while Hmp is not significantly affected. NADH oxidase activity measured under aerobic conditions in the absence of nitric oxide for Hmp was more than twice the activity of gFlHb. The addition of 1 mM hydrogen peroxide in these assays stimulated the NADH oxidase activity of gFlHb but not Hmp. Both enzymes had nearly identical cytochrome c reductase activities but the extent of the contribution of indirect reduction by flavohemoglobin-generated superoxide was much lower with gFlHb (4% SOD-inhibited) than with Hmp (17% SOD-inhibited). Although the active sites of the two enzymes share the same highly conserved residues that are important for catalysis, differences in the distal ligand binding site may account for these differences in activity and sensitivity towards NOD inhibitors. The differences observed in the NADH oxidase and cytochrome c reductase assays suggest that gFlHb may have evolved to protect the protist, which lacks both superoxide dismutase and catalase, from the damaging effects of superoxide by minimizing its production and from peroxide by actively reducing it.
An Investigation of the Magnitude of the Role of Different Plant Species in Grassland Communities on Species Diversity, China
Authors: Li Miaomiao , Ye Mao , Li Yinjuan , Zeng Guoyan , Chen Weilong , Pan Xiaoting , He Qingzhi , Zhang Xi
Published: June 2024

In this study, we selected four grassland plots in Altai forest area and used the field survey method of “two-valued occurrence” to obtain the occurrence data of each plant species in the plots so as to calculate the species diversity index value of the community as a whole and the species diversity index value of each plant species not present in the community and to make use of the difference between these two diversity indices to determine the role of each plant species in the overall species diversity of the community. The difference between these two diversity indices was used to investigate the role of each plant species in the overall species diversity of the community. The results show the following: (1) In the grassland of the Altai forest area in Xinjiang, Asteraceae, Poaceae, Fabaceae, Polygonaceae, and Rosaceae are the dominant families, among which the genera Puccinellia Parl, Taraxacum, Pharbitis, Lactuca, Geranium, and Alchemilla are the dominant genera. (2) The plant species with the greatest contribution to species diversity in the four grassland samples was not the first dominant species of the community, but rather the plant species whose dominance was in the second to sixth position. (3) The first dominant species was overwhelmingly dominant in the four sample plots, and it served to increase the overall diversity of the community. (4) The overall trend in the size of the role of species in diversity is unimodal, i.e., logarithmically increasing to a maximum as species dominance decreases and then exponentially or linearly decreasing and eventually converging to zero. The synthesis showed that it was not the first dominant species that played the largest role in species diversity in the different grassland communities and that the overwhelmingly dominant species reduced the species diversity of the community.
Identification and Functional Characterization of the SaMYB113 Gene in Solanum aculeatissimum
Authors: Yi Songheng , Cai Qihang , Yang Yanbo , Shen Hongquan , Sun Zhenghai , Li Liping
Published: June 2024

The MYB transcription factors (TFs) have substantial functions in anthocyanin synthesis as well as being widely associated with plant responses to various adversities. In the present investigation, we found an unreported MYB TF from Solanum aculeatissimum (a wild relative of eggplant) and named it SaMYB113 in reference to its homologous gene. Bioinformatics analysis demonstrated that the open reading frame of SaMYB113 was 825 bp in length, encoding 275 amino acids, with a typical R2R3-MYB gene structure, and predicted subcellular localization in the nucleus. Analysis of the tissue-specific expression pattern through qRT-PCR showed that the SaMYB113 was expressed at a high level in young stems as well as leaves of S. aculeatissimum. Transgenic Arabidopsis and tobacco plants overexpressing SaMYB113 pertinent to the control of the 35S promoter exhibited a distinct purple color trait, suggesting a significant change in their anthocyanin content. Furthermore, we obtained three tobacco transgenic lines with significant differences in anthocyanin accumulation and analyzed the differences in anthocyanin content by LC-MS/MS. The findings demonstrated that overexpression of SaMYB113 caused tobacco to have considerably raised levels of several anthocyanin components, with the most significant increases in delphinidin-like anthocyanins and cyanidin-like anthocyanins. The qRT-PCR findings revealed significant differences in the expression levels of structural genes for anthocyanin synthesis among various transgenic lines. In summary, this study demonstrated that the SaMYB113 gene has a substantial impact on anthocyanin synthesis, and overexpression of the SaMYB113 gene leads to significant modifications to the expression levels of a variety of anthocyanin-synthesizing genes, which leads to complex changes in anthocyanin content and affects plant phenotypes. This present research offers the molecular foundation for the research of the mechanism of anthocyanin formation within plants, as well as providing some reference for the improvement of traits in solanum crops.
Pressure Characteristics in the Nitrogen-Sealed Power Transformers under Internal Faults
Authors: Li Jiansheng , Jia Zheng , Wang Shengquan , Liu Shiming
Published: June 2024

The explosion-proof performance is an important index for oil-immersed transformers. The nitrogen-sealed transformer is a new type of transformer with nitrogen gas in the upper space, which can buffer against internal stress increase caused by arc faults. However, the pressure changes in the transformer under internal faults are unclear. The authors of this study propose a method based on finite element simulation to analyze the pressure changes and the stress on the tank. First, the calculation process of arc energy and the pressure of the bubbles caused by the arc are derived. Second, the dynamic pressure wave propagation model and acoustic-solid coupling model are established. Last, the finite element simulation model is built to analyze the pressure characteristics. Taking the winding turn-to-turn and phase-to-phase short circuit faults as the analysis situations, the pressure changes in the 110 kV/20 MVA nitrogen-sealed transformer are simulated. Due to the pressure wave refraction and reflection, the pressure changes show oscillatory characteristics with time after the occurrence of an internal short circuit fault. The pressure wave travels from the arc fault position to the periphery. Compared to the conventional transformer, the pressure changes with slower variations under an internal short circuit fault and the tank suffer less stress, which indicates that the nitrogen-sealed transformer is more effective in the explosion-proof performance.
Carbon Molecular Sieve Membrane Reactors for Ammonia Cracking
Authors: Cechetto Valentina , Anello Gaetano , Rahimalimamaghani Arash , Gallucci Fausto
Published: June 2024

The utilization of ammonia for hydrogen storage relies on the implementation of efficient decomposition techniques, and the membrane reactor, which allows simultaneous ammonia decomposition and hydrogen recovery, can be regarded as a promising technology. While Pd-based membranes show the highest performance for hydrogen separation, their applicability for NH3-sensitive applications, such as proton exchange membrane (PEM) fuel cells, demands relatively thick, and therefore expensive, membranes to meet the purity targets for hydrogen. To address this challenge, this study proposes a solution involving the utilization of a downstream hydrogen purification unit to remove residual ammonia, thereby enabling the use of less selective, therefore more cost-effective, membranes. Specifically, a carbon molecular sieve membrane was prepared on a tubular porous alumina support and tested for ammonia decomposition in a membrane reaction setup. Operating at 5 bar and temperatures ranging from 450 to 500 °C, NH3 conversion rates exceeding 90% were achieved, with conversion approaching thermodynamic equilibrium at temperatures above 475 °C. Simultaneously, the carbon membrane facilitated the recovery of hydrogen from ammonia, yielding recoveries of 8.2–9.8%. While the hydrogen produced at the permeate side of the reactor failed to meet the purity requirements for PEM fuel cell applications, the implementation of a downstream hydrogen purification unit comprising a fixed bed of zeolite 13X enabled the production of fuel cell-grade hydrogen. Despite performance far from being comparable with the ones achieved in the literature with Pd-based membranes, this study underscores the viability of carbon membranes for fuel cell-grade hydrogen production, showcasing their competitiveness in the field.
Dual-Band Antenna at 28 and 38 GHz Using Internal Stubs and Slot Perturbations
Authors: Bhadravathi Ghouse Parveez Shariff , Kumar Pradeep , Mane Pallavi R. , Pathan Sameena , Ali Tanweer , Boulogeorgos Alexandros-Apostolos A. , Anguera Jaume
Published: June 2024

A double-stub matching technique is used to design a dual-band monopole antenna at 28 and 38 GHz. The transmission line stubs represent the matching elements. The first matching network comprises series capacitive and inductive stubs, causing impedance matching at the 28 GHz band with a wide bandwidth. On the other hand, the second matching network has two shunt inductive stubs, generating resonance at 38 GHz. A Smith chart is utilized to predict the stub lengths. While incorporating their dimensions physically, some of the stub lengths are fine-tuned. The proposed antenna is compact with a profile of 0.75λ1×0.66λ1 (where λ1 is the free-space wavelength at 28 GHz). The measured bandwidths are 27–28.75 GHz and 36.20–42.43 GHz. Although the physical series capacitance of the first matching network is a slot in the ground plane, the antenna is able to achieve a good gain of 7 dBi in both bands. The proposed antenna has a compact design, good bandwidth and gain, making it a candidate for 5G wireless applications.
Customer focusion as a guarantee of success in tourism activities
Authors:   Peoples’ Friendship University of Russia, Moscow, Rodionov A. A.
Published: June 2024

The relevance of this topic is due to the increasing needs of clients, their wishes, travel experience, and as a result, increasing requirements for service. The article suggested three tools needed to achieve, or at least improve, the skills needed to work with clients. An employee working with a client must immediately understand HOW to behave with the client, how to offer him a product and services, and how to build communication.
Historical and cultural value of tourist objects for the development of internal tourism in the region
Authors:   Peoples’ Friendship University of Russia, Moscow, Man T. T. , Bogomolova E. S. ,   Peoples’ Friendship University of Russia, Moscow
Published: June 2024

This article discusses the important role of the historical and cultural value of tourist sites for the development of domestic tourism in the region. The article points to the importance of historical and cultural value as a driving force of economic growth and stability. Special attention is paid to the economic, social and environmental benefits of cultural and historical tourism, through which it is possible not only to acquaint people with local culture and traditions, but also to preserve the infrastructure with a characteristic culture and cultural and historical tourism, and can also contribute to innovation and business diversification in the territory