This work examines the effects of the Dzyaloshinskii–Moriya interaction (DMI) on low-field magnetic domain wall (DW) dynamics in perpendicular anisotropy CoFeB nanostripes driven by nanosecond magnetic field pulses. Micromagnetic simulations based on the Landau–Lifshitz equation were performed for DMI strengths from 0 to 1 mJ m⁻² and pulse amplitudes of 0.1 to 1 mT, which are commonly regarded to be within the creep regime. The results show that DMI significantly enhances DW displacement and velocity, with a velocity enhancement of up to approximately eight times higher than in the absence of DMI, primarily due to the emergence of a chiral Néel wall configuration and an effective DMI field that increases DW mobility. However, this enhancement does not scale linearly with DMI strength. Instead, both velocity and displacement exhibit a clear saturation behavior beyond intermediate DMI values (~0.6 mJ m⁻²). Mobility analysis, obtained by fitting simulation results to an analytical DW velocity model, indicates an increase of up to two orders of magnitude with DMI, followed by a similar plateau. These findings highlight a limit to DMI-induced enhancement in the low-field regime, with implications for optimizing DW-based spintronic devices.
During non-sterile coffee fermentation, microbial activity and substrate availability change as the mucilage is degraded. Activated carbon prepared from Arabica coffee cherry pulp by carbonization and ZnCl₂ activation was used as a support for cellulase immobilization. Cellulase produced by Cytobacillus sp. isolated from civet (Paradoxurus hermaphroditus) feces was immobilized by adsorption and used as part of the fermentation starter system. The immobilization efficiency was 80% and the immobilized cellulase had a specific activity of 613.22 U/mg. During fermentation, cellulase activity decreased from 2.45 U/mL at 0 h to 1.71 U/mL at 72 h, with approximately 70% of the initial activity remaining. At 48 h, the reducing sugar concentration was 10.7 mg/mL in the fermentation with immobilized cellulase, compared with 6.1 mg/mL in the control. The microbial growth rate was 0.132 h⁻¹ with immobilized cellulase and 0.084 h⁻¹ in the control. Pearson correlation coefficients were 0.93 between cellulase activity and reducing sugar concentration, 0.91 between reducing sugar concentration and microbial growth, and 0.88 between cellulase activity and microbial growth rate. Immobilized cellulase was associated with changes in sugar availability and microbial growth during non-sterile coffee fermentation.
Prostate cancer poses a major health challenge worldwide, with increasing incidence rates and limited current treatment modalities, which highlights the urgent need for innovative therapeutic alternatives. Utilizing nanoparticles derived from plant extracts is emerging as a promising solution, offering a superior drug delivery system. Eurycoma longifolia Jack roots, or Pasak Bumi, which are widely used in ethnobotany, are known to contain the compound eurycomanone, which exhibits pro-apoptotic activity against malignant cells. This investigation sought to assess the efficacy of Pasak Bumi root-derived nanoparticles (PBN) in inhibiting the proliferation of prostate carcinoma cells (PC-3), through an in vitro approach. A nanoparticle sample was obtained through the addition of chitosan and 0.4% Na-TPP to Pasak Bumi root extract. Flow cytometric analysis was employed to evaluate cell cycle distribution, while genes expression of Casp-3, Casp-8, and HAX-1 were quantified via qRT-PCR. The senescence cell detection test was performed using associated-β-galactosidase staining. PBN treatment supressed PC-3 cell proliferation through G0/G1 phase arrest and downregulation of HAX-1 genes expression, while promoting apoptosis via upregulation of Casp-3 and Casp-8 transcripts. PBN also increased the percentage of PC-3 senescence cells. This study demonstrates the potential of PBN to inhibit prostate cancer cells.
The mechanical behavior of materials at the nanoscale level has attracted significant attention in materials science research. This study investigated the impact of deformation on the strain energy of ultrafine-grained (UFG) copper produced by equal channel angular pressing (ECAP). X-ray and neutron diffraction techniques were employed to analyze the changes in strain energy of the copper samples subjected to varying levels of deformation. The results of the study indicate that the strain energy of the UFG copper increased with increasing levels of deformation due to the formation of dislocations with high density in the copper crystal structure. The study also found that the increase in strain energy was more significant in the initial stages of deformation and then reached a plateau as deformation progressed. This study provides valuable insight into the mechanical behavior of UFG copper and the role of deformation in altering its strain energy. The results can contribute to developing new materials with improved mechanical properties for various aerospace, automotive, and biomedical applications. The study highlights the importance of using advanced techniques such as X-ray and neutron diffraction to accurately investigate the nanoscale mechanical behavior of materials.
The conventional method for poverty measurement is the poverty line, which is based only on household income and expenditure. The poverty line can be used to determine whether a given household is poor or not. However, to capture the true nature of poverty, many factors other than income and expenditure should be considered. In this study, we developed a model for developing countries under a multidimensional framework to classify poverty levels of poor households by incorporating a fuzzy approach. The poverty levels are categorized into three levels and threshold values are determined for each level. In order to generate results, we used relevant statistical data from Sri Lanka. The results of this study indicated that individual education, income, and housing characteristics are the most significant factors in determining the poverty level of individual households in Sri Lanka. Further, the developed model provides a menu of focused factors and a policy tool for policymakers to allocate and distribute subsidies for needy areas.
