Weak Structure Research Articles

Simulation Study on Rock Crack Expansion in CO2 Directional Fracturing

In underground construction projects, traversing hard rock layers demands concentrated CO2 fracturing energy and precise directional crack expansion. Due to the discontinuity of the rock mass at the tip of prefabricated directional fractures in CO2 fracturing, traditional simulations assuming continuous media are limited. It is challenging to set boundary conditions for high strain rate and large deformation processes. The dynamic expansion mechanism of the 3D fracture network in CO2 directional fracturing is not yet fully understood. By treating CO2 fracturing stress waves as hemispherical resonance waves and using a particle expansion loading method along with dynamic boundary condition processing, a 3D numerical model of CO2 fracturing is constructed. This model analyzes the dynamic propagation mechanism of 3D spatial fractures network in CO2 directional fracturing rock materials. The results show that in undirected fracturing, the fracture network relies on the weak structures near the rock borehole, whereas in directional fracturing, the crack propagation is guided, extending the fracture’s range. Additionally, the tip of the directional crack is vital for the re-expansion of the rock mass by high-pressure CO2 gas, leading to the formation of a symmetrical, umbrella-shaped structure with evenly developed fractures. The findings also demonstrate that the discrete element method (DEM) effectively reproduces the dynamic fracture network expansion at each stage of fracturing, providing a basis for studying the CO2 directional rock cracking mechanism.

Genetic Diversity, Virulence, and Antibiotic Resistance Determinants of Campylobacter jejuni Isolates in Romania.

The emergence of antibiotic-resistant Campylobacter jejuni, a leading cause of gastroenteritis worldwide, presents a significant public health challenge requiring vigilant surveillance and disease control. This study aimed to characterize C. jejuni strains isolated in Romania from 2017 to 2020, focusing on genetic diversity, virulence, and antibiotic resistance determinants. The isolates underwent phenotypical testing, PCR, and antibiotic resistance assessment using the Kirby-Bauer disc diffusion method for ciprofloxacin, erythromycin, and tetracycline. Genetic analysis identified resistance and virulence genes, point mutations, and performed sequence typing (7-gene MLST) to determine genetic relatedness. Results indicated substitutions at position 86 in the amino acid sequence or position 257 in the nucleotide sequence of the gyrA gene in 47 fluoroquinolone-resistant isolates. Additionally, mutations in the rRNA 23S gene at positions 2074 and 2075, associated with macrolide resistance, were found in 12 of the 66 isolates. Allelic profiles generated 38 sequence types (STs), including three new STs not present in the reference database. The sequence data analysis revealed a genetically diverse C. jejuni population with a weak clonal structure. This study provides crucial insights into the genetic diversity and antibiotic resistance of C. jejuni strains in Romania, highlighting the need for ongoing surveillance and control measures.

Structures that tilt: Understanding “toxic” behaviors in online gaming

Destructive or “toxic” behaviors in online gaming have received increased attention in recent years. These are forms of verbal harassment or behavioral misconduct which disrupt another’s experience of the game. While previous explanations have explained toxic behaviors as intentional acts of deviant individuals or a larger online “trickster” culture, this article provides empirical support for a recent “tilt”-based explanation in the literature. Toxic behavior is seen as situated within and emergent from specific social contexts—as a spur-of-the-moment loss of control (associated with the term “tilt”), triggered by contextual factors within the game. Based on interview data on the popular multiplayer game League of Legends, it is shown how weak normative and relational structures within a gaming context can lead to negative emotions in players, prompting toxic behaviors. Avenues for future research and implications for improving online social spaces are discussed.

Cyclic Ether-Based Electrolyte with a Weak Solvation Structure for Advanced Potassium Metal Batteries.

Potassium metal batteries (PMBs) are promising candidates for large-scale energy storage. Conventional carbonate electrolytes exhibit unsatisfactory thermodynamic stability against potassium (K) metal anode. Linear ether is widely adopted because of its compatibility with K metal, but the poor oxidation stability restricts the application with high-voltage cathodes. Herein, a weakly solvating cyclic ether is proposed as a solvent to stabilize the K-electrolyte interface and build a robust solid-electrolyte interphase (SEI). This weakly solvating electrolyte (WSE) possesses an anion-dominated solvation structure, which facilitates the anion decomposition for constructing an inorganic-rich SEI. The superior mechanical properties of the SEI, as examined by atomic force microscopy, prevent the SEI from fracture. Consequently, this WSE achieves highly reversible plating/stripping behavior of K metal for 1300h with a high average Coulombic efficiency of 99.20%. Stable full cells are also demonstrated with a high-voltage cathode at harsh conditions. This work complements the design of WSEs for advanced PMBs by cyclic ether solvents.

Intraspecific variation in group structure arises due to environmentally-mediated directional dispersal in a cooperative breeder.

Many cooperatively breeding species live in groups with complex structure-large group sizes, low and variable kin structure, and multiple breeding pairs. Since these mixed-kin groups typically form because of immigration of unrelated individuals of both sexes in addition to limited offspring dispersal, differences in patterns of dispersal can generate variation in group structure, even within the same species or population. Here, we examine how environmentally mediated dispersal patterns influence variation in group structure in the plural breeding superb starling (Lamprotornis superbus), an avian cooperative breeder that inhabits a spatiotemporally variable savanna environment and forms mixed-kin groups with variable group sizes and more than one breeding pair per group. Using 4068 genome-wide polymorphic loci and fine-scale, remotely sensed ecological data from 22 groups sampled across a nearly 200 km2 environmental gradient in central Kenya, we find evidence of not only frequent and long-distance dispersal in both sexes (low isolation-by-distance and weak genetic structure), but also directional dispersal from small groups in lower quality habitat with low normalised difference vegetation index (NDVI) to large groups in higher quality habitat with high NDVI. Additionally, we find stronger genetic structure among groups in lower quality habitat, and higher genetic diversity and lower relatedness of groups in higher quality habitat. Previous work using long-term data from groups in the same population has shown that groups with lower relatedness are larger and have more breeding pairs. Long-distance, directional dispersal to maximise individual fitness can thus lead to smaller and simpler kin-based social groups in lower quality habitat, but larger and more complex mixed-kin groups in higher quality habitat. Such intraspecific, within-population variation in group structure, including variation in kin structure of social groups, could have profound implications for the relative importance of the evolutionary mechanisms (i.e. direct vs. indirect fitness benefits) underlying the formation of cooperative societies.

Species assemblages and their drivers differ between trees and lianas in a seasonal evergreen forest in Thailand

AbstractDespite a long tradition in ecology of studying tree species assembly and its potential drivers in tropical forest communities, little information exists with respect to lianas (woody climbers), the second most abundant life form of woody plants in tropical forests. Lianas influence forest diversity and stability and provide critical resources for forest fauna. Using a unique dataset of a 30‐ha plot in Thailand, where tree and liana individuals were fully mapped, we investigated the degree to which local species assemblages of trees and lianas of different size classes (i.e., seedlings, established individuals, and large individuals) are related to local environmental conditions. We asked (1) What are the spatial patterns and environmental drivers of local tree and liana species assemblages? (2) How do such patterns and drivers differ among size classes? (3) Which species associate with these assemblages? Local assemblages of established trees showed substantial structuring by environmental variables, whereas we found only weakly structured assemblages of tree seedlings, large trees, and lianas of all size classes. Our results indicated that the biotic and abiotic drivers of local species assemblages differed strongly between tree and liana communities and across size classes. Species assemblages of trees were mainly driven by soil nutrients, leading to patchy assemblages associated with high base saturation (Alfisols) and assemblages associated with lower levels of base saturation and higher aluminum (Ultisols), whereas tree seedling assemblages were only weakly structured by riparian zones. In contrast, species assemblages of established and large lianas were primarily associated with forest canopy structure, separating low‐canopy forests from high‐canopy forests, whereas soil nutrients were the only factors associated with liana seedling assemblages. The weak environmental structuring of tree seedlings and large trees suggests that other mechanisms, such as stochastic disturbances, competition for space, or animal seed dispersal, may play an important role in structuring tree communities in this seasonal tropical forest. The weak patterns observed in liana communities across all life stages raise questions about the underlying mechanisms of liana community assembly, and further research should focus on liana niches, their dispersal mechanisms, and host tree relations.

Powerful QTL mapping and favorable allele mining in an all-in-one population: a case study of heading date.

The multiparent advanced generation intercross (MAGIC) population is characterized with great potentials in power and resolution of quantitative trait locus (QTL) mapping, but single nucleotide polymorphism (SNP)-based GWAS does not fully reach its potential. In this study, a MAGIC population of 1021 lines was developed from four Xian and four Geng varieties from five subgroups of rice. A total of 44000 genes showed functional polymorphisms among eight parents, including frameshift variations or premature stop codon variations, which provides the potential to map almost all genes of the MAGIC population. Principal component analysis results showed that the MAGIC population had a weak population structure. A high-density bin map of 24414 bins was constructed. Segregation distortion occurred in the regions possessing the genes underlying genetic incompatibility and gamete development. SNP-based association analysis and bin-based linkage analysis identified 25 significant loci and 47 QTLs for heading date, including 14 known heading date genes. The mapping resolution of genes is dependent on genetic effects with offset distances of <55kb for major effect genes and <123kb for moderate effect genes. Four causal variants and noncoding structure variants were identified to be associated with heading date. Three to four types of alleles with strong, intermediate, weak, and no genetic effects were identified from eight parents, providing flexibility for the improvement of rice heading date. In most cases, japonica rice carries weak alleles, and indica rice carries strong alleles and nonfunctional alleles. These results confirm that the MAGIC population provides the exceptional opportunity to detect QTLs, and its use is encouraged for mapping genes and mining favorable alleles for breeding.

Weakly coupled photonic flexible sensors based on sodium polyacrylate

The flexible optical fiber sensor serves as a prototype for highly sensitive photonic skin flexible sensors (PSFS) with rapid response times, facilitating the development of advanced wearable healthcare devices. Future bionic skin sensors, tailored for wearable devices focusing on health monitoring and robotics applications, will necessitate the incorporation of optical systems. In this work, PSFS based on weak coupling structure is proposed for the first time. This structure comprises a fiber optic sensor with weak coupling as the core sensing node, and the sensing material is hydrophilic and flexible sodium polyacrylate (SPA). The SPA combines the high sensitivity of PSFS with excellent biocompatibility, enabling both static and dynamic sensing measurements for physical parameters such as humidity and temperature. Leveraging the strain amplification effect of the single-mode tapered fiber and the unique fiber structure, the material's sensitivity to relative humidity (RH) is significantly enhanced, reaching 0.19 dB/%RH. Furthermore, the temperature response demonstrates exceptional sensitivity (0.29 dB/℃) within the range of human skin surface temperatures (30–48℃). Remarkably, the sensor has a significant response time of 128 ms. This research proposes a novel approach for constructing highly sensitive and versatile PSFS, which is critical for health care monitoring.

Ozone induced structural variation in OSA waxy rice starch: Effects on the thermal behavior of starch and its stabilized pickering emulsion

Waxy rice starch (St) was modified by pre-OSA esterification reaction followed by ozone treatment. The molecular structure of this modified product (OSA-OSt) was characterized, and the thermal behaviors and its stabilized Pickering emulsion were evaluated. 1HNMR and XPS results discovered that ozone initially oxidized the hydroxyl groups in the amorphous region of starch (preferentially C2/C3) along with a degree of crosslinking, enhancing the molecular orderliness. This led to an increase in water-holding capability (29.15%) and swelling power (52.8 g/g), and a decrease in solubility (0.35%). TGA, RVA, and DSC indicated that oxidation-induced crosslinking within a brief treatment period enhanced the starch's thermal stability. The structural change enabled the formation of a weak gel structure during the heating process, which displayed high thermal and freeze-thaw stability. The work proves ozone is an effective way of improving the thermal behavior of OSA-starch and its emulsion for subsequent applications in numerous food products.

Weak Hopf symmetry and tube algebra of the generalized multifusion string-net model

We investigate the multifusion generalization of string-net ground states and lattice Hamiltonians, delving into their associated weak Hopf symmetries. For the multifusion string-net, the gauge symmetry manifests as a general weak Hopf algebra, leading to a reducible vacuum string label; the charge symmetry, serving as a quantum double of gauge symmetry, constitutes a connected weak Hopf algebra. This implies that the associated topological phase retains its characterization by a unitary modular tensor category (UMTC). The bulk charge symmetry can also be captured by a weak Hopf tube algebra. We offer an explicit construction of the weak Hopf tube algebra structure and thoroughly discuss its properties. The gapped boundary and domain wall models are extensively discussed, with these 1d phases characterized by unitary multifusion categories (UMFCs). We delve into the gauge and charge symmetries of these 1d phases, as well as the construction of the boundary and domain wall tube algebras. Additionally, we illustrate that the domain wall tube algebra can be regarded as a cross product of two boundary tube algebras. As an application of our model, we elucidate how to interpret the defective string-net as a restricted multifusion string-net.

Geomechanical properties of laminated shale and bedding shale after water absorption: A case study of the Chang 7 shale in Ordos basin, China

There are abundant oil and gas resources in China's continental shale formations, and these formations often contain sandy lamina, tuffaceous lamina and carbonate lamina parallel to the bedding planes, resulting in complex geomechanical properties. During the drilling process, the mechanical weak surface structure inside the shale and the hydration effect of drilling fluid may easily cause wellbore instability, which reduces the safety and benefit of drilling. To explore the geomechanical properties of laminated shale and bedding shale after water absorption, a series of tests were conducted on the Chang 7 laminated shale and bedding shale in the Ordos Basin. The result indicates that the compressive strength and elastic modulus of laminated shale and bedding shale show a trend of decreasing first and then starting to drop as β (the angle between bedding/lamina and the direction of stress) keeps increasing, and laminated shale has stronger anisotropy, lower compressive strength and elastic modulus. The moisture content of laminated shale and bedding shale increases as the soaking time increases, which leads to a decrease in the compressive strength. Compared to bedding shale, laminated shale reaches water saturation faster and has a higher moisture content. Based on the macroscopic and microscopic images before and after shale hydration, it can be concluded that natural microfractures are easily formed at the interface between the lamina and shale matrix, and brittle minerals at the edges of natural microfractures are prone to detachment, thereby increase the hydration area and intensify the hydration process. Compared to bedding shale formations, laminated shale formations have a higher hole-size elongation ratio and are more prone to collapse according to on-site data. This study reveals the geomechanical properties of laminated shale under the dual influence of anisotropy and hydration, provides support for drilling design in such formations.

Diversity Analysis of Fungi Distributed in Inhalable and Respirable Size Fractions of Aerosols: A Report from Kuwait

Fungi are an important part of the atmospheric ecosystem yet an underexplored group. Airborne pathogenic fungi are the root cause of hypersensitive and allergenic states highly prevalent in Kuwait. Frequent dust storms in the region carry them further into the urban areas, posing an occupational health hazard. The fungal population associated with the respirable (more than 2.5 µm) and inhalable (2.5 µm and less) fractions of aerosols is negligibly explored and warrants comprehensive profiling to pinpoint tAhe health implications. For the present investigation, aerosol was collected using a high-volume air sampler coupled with a six-stage cascade impactor (Tisch Environmental, Inc) at a rate of 566 L min−1. The samples were lysed, DNA was extracted, and the internal transcribed regions were sequenced through targeted amplicon sequencing. Aspergillus, Penicillium, Alternaria, Cladosporium, Fusarium, Gleotinia and Cryptococcus were recorded in all the size fractions with mean relative abundances (RA%) of 17.5%, 12.9%, 12.9%, 4.85%, 4.08%, 2.77%, and 2.51%, respectively. A weak community structure was associated with each size fraction (ANOSIM r2 = 0.11; p &gt; 0.05). The Shannon and Simpson indices also varied among the respirable and inhalable aerosols. About 24 genera were significantly differentially abundant, as described through the Wilcoxon rank sum test (p &lt; 0.05). The fungal microbiome existed as a complex lattice of networks exhibiting both positive and negative correlations and were involved in 428 functions. All the predominant genera were pathogenic, hence, their presence in inhalable fractions raises concerns and poses an occupational exposure risk to both human and non-human biota. Moreover, long-range transport of these fungi to urban locations is undesirable yet plausible.

Analisis Faktor Keamanan Dan Probabilitas Kelongsoran Lereng Di Jalan Batu Besaung Kelurahan Sempaja Utara Kecamatan Samarinda Utara Kota Samarinda Provinsi Kalimantan Timur

A slope is an area of ​​morphology that has a certain geometry, namely the highest and lowest parts and has the potential for landslides if it is in an unstable condition (Wesley &amp; Pranyoto, 2010 in Khodijah, et al, 2022). A slope can be composed of soil, rock, or both. Slope stability is influenced by slope geometry, physical and mechanical characteristics of the slope-forming material, water (hydrology and hydrogeology), rock weak plane structure (location, direction, frequency, mechanical characteristics), natural stresses in the rock mass, local stress concentrations, vibrations ( natural: earthquakes; and human actions: effects of blasting, effects of heavy equipment passing by), climate, the results of mine workers' actions, and thermic effects (Moshab, 1997 in Arif, 2016).

Ice-shelf freshwater triggers for the Filchner–Ronne Ice Shelf melt tipping point in a global ocean–sea-ice model

Abstract. Some ocean modeling studies have identified a potential tipping point from a low to a high basal melt regime beneath the Filchner–Ronne Ice Shelf (FRIS), Antarctica, with significant implications for subsequent Antarctic ice sheet mass loss. To date, investigation of the climate drivers and impacts of this possible event have been limited because ice-shelf cavities and ice-shelf melting are only now starting to be included in global climate models. Using a global ocean–sea-ice configuration of the Energy Exascale Earth System Model (E3SM) that represents both ocean circulations and melting within ice-shelf cavities, we explore freshwater triggers (iceberg melt and ice-shelf basal melt) of a transition to a high-melt regime at FRIS in a low-resolution (30 km in the Southern Ocean) global ocean–sea-ice model. We find that a realistic spatial distribution of iceberg melt fluxes is necessary to prevent the FRIS melt regime change from unrealistically occurring under historical-reanalysis-based atmospheric forcing. Further, improvement of the default parameterization for mesoscale eddy mixing significantly reduces a large regional fresh bias and weak Antarctic Slope Front structure, both of which precondition the model to melt regime change. Using two different stable model configurations, we explore the sensitivity of FRIS melt regime change to regional ice-sheet freshwater fluxes. Through a series of sensitivity experiments prescribing incrementally increasing melt rates from the smaller, neighboring ice shelves in the eastern Weddell Sea, we demonstrate the potential for an ice-shelf melt “domino effect” should the upstream ice shelves experience increased melt rates. The experiments also reveal that modest ice-shelf melt biases in a model, especially at coarse ocean resolution where narrow continental shelf dynamics are not well resolved, can lead to an unrealistic melt regime change at downstream ice shelves. Thus, we find that remote connections between melt fluxes at different ice shelves are sensitive to baseline model conditions. Our results highlight both the potential and the peril of simulating prognostic Antarctic ice-shelf melt rates in a low-resolution global model.

Perceptions and views of key implementers on the implementation of the health-promoting school programme in the City of Tshwane, South Africa.

The health-promoting school programme has been associated with numerous benefits for school communities where it is well implemented. In Tshwane, the implementation processes have not been evaluated. A qualitative research approach based on grounded theory was used to investigate the experiences of 27 health-promoting school programme implementers across Tshwane. Data were collected through a combination of methods, including semi-structured interviews with principals (n=6), educators (n=10) and school governing body members (n=4), one focus group discussion with health promoters (n=7), field notes from school observations and memos. Implementation fidelity was weak in the City of Tshwane, as a result of poor training of implementers, poor leadership and collaboration, weak accountability structures, and lack of resources and communication. A grounded theory was developed which showed that schools needed guidance and accountability to properly implement the programme. The theory offers a framework that could be used to improve implementation and evaluation outcomes. Implementers were keen on improving the lives of learners - health-wise and academically. With proper guidance, support and accountability measures by government at district and provincial level, implementation of the programme is feasible in the City of Tshwane.

Investigation into the Time-Dependent Characteristics of Stress and Deformation of Weak Surrounding Rock and Lining Structure in Operational Tunnels: Model Test

During the long-term operation of tunnels, surrounding rock undergoes creep effects under environmental loads, resulting in changes in the aging evolution model of stress and deformation in surrounding rock and lining, which affects the long-term operational safety of the tunnel. Therefore, using the model test device for time-dependent characteristics of stress and deformation of weak surrounding rock and lining structure in operational tunnels, taking into account the influence of tunnel burial depth and lateral pressure coefficient of surrounding rock, a model test on time-dependent characteristics of stress and deformation in weak surrounding rock and lining structure was conducted, and the stress and deformation time-varying curves at key locations of surrounding rock and lining were obtained. The time characteristics of surrounding rock stress, the contact force between surrounding rock and lining, internal force, and displacement of lining structure were analyzed. Research findings indicate that the stress of surrounding rock, the internal force and displacement of lining structure, and the contact force between surrounding rock and lining all increase and tend to be stable over time under constant load. This implies that the stress and deformation of the surrounding rock and lining structure exhibit time-dependent changes. With changes in burial depth and lateral pressure coefficient, significant variations are observed in the various indicators of stress and deformation in the surrounding rock and lining structure, indicating both time-dependent and long-term characteristics in terms of stress and deformation. The research results provide basic data support for the study of the time-dependent characteristics of stress and deformation between weak surrounding rock and lining structures in operational tunnels and can provide theoretical and technical guidance for the long-term service status discrimination and disaster prevention and control of operational tunnels.

Rheological aspects of solid-to-liquid phase transitions in paraffin wax/bitumen blends for thermal energy storage applications

This paper correlates the evolution of the rheological and thermal properties with microstructure during the phase change of a blend of bitumen with a selected paraffin wax, having a melting point centred around 60 °C, for the development of bituminous based membranes for thermal energy storage applications. For this purpose, temperature sweep tests within the linear viscoelastic range, stationary state flow curves, Differential Scanning Calorimetry (DSC), polarised optical microscopy observations and solar irradiation tests were performed. The reported rheological results clearly point out a gel-like behaviour for both paraffin and paraffin/bitumen blend that is preserved almost up to the end of the phase change interval. This is consequence of the development of a network of interconnected crystals of paraffin wax which progressively disappear as temperature increases. Interestingly, a weak gel structure is kept even at low crystallinity levels since only a few junctions among structures are necessary to build a spanning network. Finally, the large degree of crystallinity of paraffin wax retained in the bitumen/paraffin wax is behind its thermoregulation ability, as was corroborated by solar irradiation tests. Therefore, results indicated the great potential of these formulations for thermal energy storage and related applications.

Board Diversity and Earnings Quality of Listed Deposit Money Banks in Nigeria

Investors’ confidence in the financial reporting process has been hampered because of unethical accounting practices and earnings management and this could be as a result of weak governance structures. The main objective of this study therefore was to examine the effect of board diversity on earnings quality of deposit money banks listed on the floor of the Nigerian Exchange Group from 2014-2023. The independent variable of the study was proxied by board age diversity, board experience diversity and board financial expertise, while the dependent variable was proxied by discretionary loan loss provision. The research design adopted for this study was ex post facto because secondary data were used. The sample size of this study was 10 deposit money banks purposively selected. Ordinary least square regression was used to analyze the data used and statistical software package employed was E-view version 10. The findings of the study revealed that board age diversity has a non-significant negative effect on the discretionary loan loss provisions; experience diversity and board financial expertise have significant negative effect on discretionary loan loss provisions of listed deposit money banks in Nigeria. Thus, it was concluded that board diversity has significant influence on earnings quality of listed deposit money banks in Nigeria. Therefore, it was recommended that the management of deposit money banks should prioritize recruiting board members with robust financial background and expertise to enhance both their earnings quality and financial risk management strategies.

Effects of plasma-activated water combined with ultrasonic treatment of corn starch on structural, thermal, physicochemical, functional, and pasting properties

In this study, corn starch was used as the raw material, and modified starch was prepared using a method combining plasma-activated water and ultrasound treatment (PUL). This method was compared with treatments using plasma-activated water (PAW) and ultrasound (UL) alone. The structure, thermal, physicochemical, pasting, and functional properties of the native and treated starches were evaluated. The results indicated that PAW and UL treatments did not alter the shape of the starch granules but caused some surface damage. The PUL treatment increased the starch gelatinization temperature and enthalpy (from 11.22 J/g to 13.13 J/g), as well as its relative crystallinity (increased by 0.51 %), gel hardness (increased by 16.19 %) compared to untreated starch, without inducing a crystalline transition. The PUL treatment resulted in a whitening of the samples. The dual treatment enhanced the thermal stability of the starch paste, which can be attributed to the synergistic effect between PAW and ultrasound (PAW can modify the starch structure at a molecular level, while ultrasound can further disrupt the granule weak crystalline structures, leading to improved thermal properties). Furthermore, FTIR results suggested significant changes in the functional groups related to the water-binding capacity of starch, and the order of the double-helical structure was disrupted. The findings of this study suggest that PUL treatment is a promising new green modification technique for improving the starch structure and enhancing starch properties. However, further research is needed to tailor the approach based on the specific properties of the raw material.

A case report of urethral prolapse in young girls: Clinical manifestations and surgical management

Background and importanceUrethral Prolapse (UP), first described by Solinger in 1732, is a rare condition characterized by the circular protrusion of the distal urethral mucosa through the external meatus, forming a hemorrhagic, sensitive vulvar mass. This condition is most commonly observed in prepubertal black females. This case report details the clinical manifestations and surgical management of UP in three young girls. Cases presentationThree girls, aged 4, 5, and 6 years, were admitted with symptoms of vaginal blood spotting. Physical examinations revealed moderate bleeding and a red ring of congested, edematous tissue prolapsing through the urethral meatus. Diagnostic procedures confirmed UP, and surgical management was undertaken. The surgical approach involved the complete excision of the prolapsed tissue and mucosal-to-mucosal anastomosis under general anaesthesia. Postoperative follow-up over a mean period of 11 years showed no recurrence or urethral stricture. Clinical discussionUP is a rare benign condition primarily affecting the female urethra, with several hypothesized etiologies, including weak pelvic floor structures and increased intraabdominal pressure. The typical presentation includes vaginal bleeding and a doughnut-shaped mass around the urethral meatus. Conservative management may be considered for mild cases, but surgical excision is recommended for severe cases, offering a safe and effective solution with low recurrence rates. ConclusionsUP in children, although rare, should be considered in cases of unexplained vaginal bleeding. Diagnosis is primarily clinical, and surgical resection provides a definitive and cost-effective treatment.