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Biofences: A successful system for cleaning waterways in Montevideo, Uruguay
Full text linkIn Montevideo, waterways are used by citizens and by small and medium-sized commercial waste generators (both regulated and unregulated) as sites for the final disposal of solid waste. Additionally, they act as recipients of surface runoff from the basin during rainfall. The improper disposal of waste is considered one of the most underestimated forms of environmental degradation while also having a significant visual impact. To contribute to the development of comprehensive environmental management guidelines for water bodies, the Department of Environmental Engineering at the Institute of Fluid Mechanics and Environmental Engineering (DIA-IMFIA) developed a project in collaboration with the Montevideo City Government (IM). The main objective was to evaluate and propose recommendations to minimize the presence and persistence of solid waste in water bodies. For this purpose, a point in the Chacarita stream in Montevideo was chosen as the study area. A biofence was installed as a retention device to quantify waste, based on the analysis of retention devices successfully implemented in other Latin American countries. Non-returnable plastic beverage containers were reused for the construction of the biofence. The working methodology involved defining the study area together with the IM. Subsequently, in this area, a diagnosis was conducted to assess the current functioning of waste management systems. The installed biofence proved to be an effective system for retaining floating solid waste, capturing approximately 290 kg of waste during the 16 days it was in operation. Based on the results obtained, the DIA-IMFIA team has collaborated with the IM to train its staff in the construction, installation, and operation of bio-barriers. Throughout 2024, the IM has consolidated the implementation of bio-barriers in other water bodies in Montevideo as an institutional line of work
Characterization of posinormal operators with closed ranges
Full text linkCharacterization of posinormal operators in terms of their positivity, invertibility and numerical ranges has been done. However, characterization of these operators with regards to their closed ranges remains interesting. In this work, we characterize conditions for posinormal operators to have closed ranges. In particular, we establish an important upper norm bound criterion for posinormal operators. We show that if Q, R are normal operators in PN (H), the set of all posinormal operators acting on a Hilbert space H and suppose that the range of Q is closed with the null space of Q equal to the null space of R, then the range of R is closed. The results of this study are very useful applications in many areas, like image and signal processing. In particular, they are useful in processing signals and images used in facial recognition which are important in the identification of people in places like the airports, thus helping in enhancing security and forensic analysis
Determinants of corporate social responsibility in Tunisian context
Full text linkThis paper examines the various determinants of corporate social responsibility (CSR) and assesses the impact of each on CSR practices. Drawing on a solid theoretical framework, we consider factors such as firm characteristics and governance mechanisms. In addition to the CSR determinants, we also explain the effect of the COVID-19 pandemic. This research aims to enrich the CSR literature and provide concrete perspectives for professionals wishing to strengthen their commitment to CSR
Experimental investigation of low resistance joints for high field HTS magnets
Full text linkHigh-temperature superconducting (HTS) tapes are now commercially available for various magnet applications. Their higher tensile strength enhances strain tolerance, allowing for the winding of smaller diameter coils. The most crucial component in a double pancake winding of a coil is the fabrication of inter-double pancake joints with minimal electrical resistance. This is due to the structural design of REBCO (RE—rare earth) tape, which consists of very thin layers of materials prone to deterioration when exposed to temperatures exceeding the recommended value, optimal joint overlap length, and the selection of solder materials. In this study, we investigated the effects of tape overlap lengths, solder materials, and soldering temperatures on joint resistance. The lowest joint resistance recorded was 18 nΩ, achieved with an overlap length of 150 mm at 4.2 K in a self-field, as reported in this paper for a 3.5 T REBCO coil winding pack
An efficient optimized deep learning model for diabetic retinopathy classification
Full text linkOne of the most common disorders worldwide is diabetes, a metabolic condition marked by elevated blood sugar levels. Complications from diabetes can lead to diabetic retinopathy (DR). Later stages of DR can result in blindness, while early stages may only produce slight vision abnormalities or no symptoms at all. Diagnosing diabetic retina (DR) is particularly challenging due to changes in the retina that occur with the stages of the illness. An autonomous DR early detection device can help ophthalmologists with DR screening while also protecting a patient’s vision. The Ensemble of EfficientNet-B0, a unique approach based on the Modified Sparrow Search Algorithm (EMSSA) that provides more accurate classification with less processing time, is presented in this study. The proposed EMSSA regularized classification is carried out after the images have been pre-processed, segmented, and dimension-reduced features constructed using the suggested algorithms. Five phases of non-proliferative images were used in the experiment: Proliferative, moderate, mild, severe, and non-proliferative. By using dimensionally reduced data, the suggested approach reduces complexity and produces an accuracy rate of 98.8%. According to an examination of performance metrics, the system performs better than other cutting-edge methods in terms of F-measures, accuracy, recall, and precision
Rhamnazin Inhibits Malignant Progression of ProstateCancer Cells via DPP4/JAK/STAT Signaling Pathway
Full text linkBackground: Rhamnazin is a natural dimethoxyflavonoid compound and Rhamnazin has been reported to have antitumor activity. This work is performed to study the function of Rhamnazin in prostate cancer (PCa) cells and its mechanism.
Methods: Rhamnazin (20 µM) was used to treat 22Rv1 and C4-2B cells, and the cells treated with dimethyl sulfoxide (DMSO)
were set as the control group. To investigate the role of dipeptidyl peptidase 4 (DPP4) in mediating the biological effects of Rhamnazin, DPP4 overexpression plasmids were transfected into the PCa cell lines. Cell counting kit-8 method was employed to detect
the proliferation; apoptosis and cell cycle were detected by flow cytometry. the target genes of Rhamnazin were predicted in
Traditional Chinese Medicine Systems Pharmacology (TCMSP) database. Gene Ontology and Kyoto Encyclopedia of Genes and
Genomes enrichment analysis of target genes of Rhamnazin was performed using the Database for Annotation, Visualization
and Integrated Discovery (DAVID database). Human Protein Atlas database was utilized to identify genes associated with poor
PCa prognosis. GEPIA database was used to validate the expression and prognosis of DPP4 in PCa. The LinkedOmics database
was used to analyze the signaling pathway related to DPP4 in PCa. Quantitative polymerase chain reaction was performed to
detect DPP4 mRNA levels. Western blot assays were performed to detect the expression levels of DPP4, phosphorylated (p-)
Janus kinase 1 (JAK1) and p-signal transducer and activator of transcription 3 (STAT3).
Results: Functional assays confirmed that Rhamnazin inhibited the proliferation of PCa cells (p < 0.05), and promoted apoptosis
(p < 0.05) and blocked the cell cycle progression (p < 0.05). In addition, Rhamnazin significantly inhibited the expression of DPP4
(p < 0.05), and up-regulating DPP4 reversed the effects of Rhamnazin (p < 0.05). It was further found that DPP4 was associated
with JAK/STAT signaling and Rhamnazin inhibited the expression of p-JAK1 (p < 0.05) and p-STAT3 (p < 0.05) through DPP4.
Conclusion: Rhamnazin has the potential to kill PCa cells via DPP4/JAK/STAT axis
Effects of Histone Deacetylase 2 onEpithelial-Mesenchymal Transition in PulmonaryFibrosis
Full text linkBackground: Pulmonary fibrosis (PF) is a chronic and progressive interstitial lung disease. Histone deacetylases (HDACs) play
a crucial role in the onset and development of PF. Changes in HDACs 1–10 expression levels occur during PF development, and
their specific roles remain unclear. Therefore, we elucidated changes in the gene and protein levels of HDACs 1–10. Furthermore,
we selectively knocked down HDAC2 to explore the molecular mechanism underlying the regulatory role of HDAC2 in epithelialmesenchymal transition (EMT) during the development of PF.
Methods: Lewis lung carcinoma (LLC) cells were stimulated with transforming growth factor-β1 (TGF-β1) (5 ng/mL) to establish
a lung fibrosis cell model. Additionally, C57BL/6 mice received bleomycin through single intratracheal instillation at a 3.5 mg/kg
volume, diluted in 0.7 mL saline. Furthermore, EMT-related gene and protein expression levels were assessed using quantitative
PCR (qPCR) and Western blotting, respectively.
Results: We observed that HDAC2 expression levels were significantly increased in both the in vitro and in vivo PF models.
HDAC2 knockdown significantly decreased the expression levels of fibrosis indicators such as collagen type I (Col-I) and collagen
type IV (Col-IV), and EMT indicator α-smooth muscle actin (α-SMA) was observed. Conversely, it increased the expression
of EMT indicator E-cadherin (E-cad). Hematoxylin and eosin (H&E) and Masso staining revealed that HDAC2 knockdown
substantially reduced the degree of pulmonary fibrosis. These findings suggest that lowering HDAC2 expression inhibits EMT
and reduces PF. Moreover, in a TGF-β1-induced lung fibrosis cell model, HDAC2 knockdown significantly reduced epithelial
growth factor receptor levels, which inhibited mitogen-activated protein kinases (MAPK) signaling and decreased the protein
expression of p38 and c-Jun N-terminal kinase (JNK).
Conclusions: HDAC2 knockdown effectively impedes EMT and diminishes PF severity, impacting the JNK/p38 MAPK signaling
pathway, which may serve an inhibitory function
Analysis of educational policies and environmental culture among Peruvian university students
Full text linkEnvironmental culture in university students refers to the set of knowledge, values and behaviors that they acquire and practice with the protection of the environment within their academic space, supported by environmental educational policies. We proposed to understand the existence of an inadequate environmental culture in university students. The objective of this study was to analyze university educational policies and environmental culture in Peruvian students, comparing the results according to sociodemographic variables. A total of 2448 intentionally chosen university students participated, a non-experimental cross-sectional design was used, a quantitative approach of comparative descriptive level was used. In addition, in the data analysis, the descriptive results are presented in a table of frequencies and percentages, while the inferential analyses are presented in statistics. A medium level of environmental culture was found at 57.3% with a tendency to be low at 37.3% in university students. In addition, the comparison of sociodemographic variables indicates that there are statistically significant differences (p < 0.05), therefore, the students from public universities, the area of social sciences and the last years of study present higher scores than the other comparison groups. In conclusion, environmental educational policies have not been adequate and applied by universities to generate an adequate environmental culture in university students within the academic field
Liminality and the metaverse: An analysis of mytho-liminal and mystic-liminal games and their impact on player identity
Full text linkThe article explores the impact of liminality in immersive games on players’ identity from two perspectives: overcoming liminal phases associated with the initiation of a character in games with a narrative-plot architecture that reflects the universal stages of the hero’s “journey”; and overcoming liminality in survival horror games, where players use the virtual world to experiment with their psyche. It introduces and substantiates the terms of mytho-liminal and mystical-liminal games, assessing their positive and negative effects based on data from semi-structured interviews with student groups, totaling 120 informants. After processing the interview data and deriving quantitative indicators, the findings were refined and justified through the lens of research on liminal states, game psychology, and psychological studies on out-of-body experiences in virtual reality. It has been found that the positive effects of mystical-liminal games include the experience of emotions unattainable in the real world, development of coping potentials, working through unconscious conflicts and psychological traumas, and strengthening the moral imperative with a clear distinction between good and evil. The negative impact of mystical liminality manifests in feelings of fear, tension, and discomfort during gameplay, feelings of helplessness and frustration in cutscenes, and cognitive stress due to disidentification with the projective identity when the player’s “positive” avatar is transformed into an immoral character. The positive effects of mytho-liminal games include: enhancement of the sense of subjectivity, awareness of an ideal to emulate, strengthening of the value component of personality, development of creativity and problem-solving skills, unleashing positive potential of latent, unrealized possibilities, development of communication skills, and liberation from social conventions. Negative effects include self-dissociation and depersonalization in both psychological and physical terms, realization of latent destructive needs and deviant behavior, and the substitution of real initiation–finding one’s “self”–with pseudo-initiation through gameplay. This research provides insights into the intersection of liminal and virtual realities, shedding light on the psychological dimension of liminality in video games and enhancing the overall understanding of the liminality role in the virtual context
Leveraging and combining resources for sustainable urban agriculture development in major Vietnamese cities
Full text linkCities serve as principal economic hubs within the nation, characterized by unique socio-economic conditions and potential that present advantages as well as challenges for future economic advancement. The swift urbanization process is associated with the increasing demand for safety and sustainable development, especially in major cities like Ho Chi Minh City in Vietnam. Notably, sustainable urban agriculture, which is an integral component of the increasing movements towards locally sourced food, is a significant concern and is prioritized in the city’s comprehensive planning. This review paper presents models of agricultural development, emphasizing the synthesis, analysis, and evaluation of diverse resources—both their individual effects and their collaborative interactions with urban development—alongside the principal benefits and challenges in optimizing and utilizing these resources for optimal effectiveness. Additionally, this paper also suggests strategies to optimize resource utilization and foster the establishment of a sustainable, adaptable, and efficient urban agricultural system