Negative Potential Research Articles

Facile and highly sensitive nitrate ion detection via an electrochemical sensor based on a poly 1,8-diaminonaphthalene and copper oxide particle film.

Excessive nitrate accumulation in soil and water has become a critical environmental concern, threatening ecosystems and public health. This drives the need for designing new electrochemical nitrate sensors based on novel electroactive materials. In this work, we synthesized a hybrid film material composed of poly 1,8-diaminonaphthalene and copper oxide particles electrodeposited on the surface of a carbon paste electrode (Cu2O-CuO/poly 1,8-DAN/CPE). The electrodeposition of the polymer was conducted in galvanostatic mode at a positive current, followed by the electrodeposition of copper in potentiostatic mode at a negative potential. The polymeric film obtained through this facile electropolymerization method showed a uniform dispersion of copper particles and could improve the mechanical stability of the fabricated sensors, thereby leading to a low detection limit of nitrate ions. The Cu2O-CuO/poly 1,8-DAN/CPE was prepared in just 3 min in both the galvanostatic and potentiostatic mode. The developed sensor exhibited a good electrochemical performance for nitrate ions, with a linear range from 2 to 200 μM, strong stability, high reproducibility, and a low detection limit of 0.5 μM. This work revealed that the deposition of polymer can be applied as a promising material in new applications, such as water denitrification.

Automatic and affective processing of faces as mechanisms of passing as non-autistic in adolescence

Passing as non-autistic (PAN) is the phenomenon by which an autistic person does not present as autistic in certain contexts. Despite a proliferation of research on the construct on PAN, no study has yet examined the neurocognitive processes implicated in PAN. This study examined two well-characterized event-related potentials (ERPs) often associated with autism - the N170 and the Late Positive Potential (LPP) - in response to faces as putative mechanisms of PAN. Participants were 44 community-recruited youth (Mage = 13.36, Nmale = 30) who completed a facial emotion recognition task during EEG recording. PAN was operationalized using best practices (moderation) for calculating the discrepancy between community informant (parent and teacher) and clinician-reported autism symptoms. Results reveal a substantial proportion (approximately 44%) of the community-recruited adolescent sample met criteria for PAN. This status was associated with faster N170 latency to faces, and attenuated LPP amplitude to facial emotions, particularly subtle facial emotions. Findings suggest autistic adolescents who PAN may have more efficient automatic process of, and reduced reactivity to, social stimuli. This study provides the first direct test of a potential neurocognitive mechanism of PAN, supporting emotion regulation-mediated PAN models.

Ion-acoustic wave propagation with Bohm quantum potential near and at supercritical values in degenerate plasmas

This research investigates the nonlinear propagation of solitons and periodic oscillatory waves near and at supercritical values (S-CVs) in a relativistic degenerate plasma consisting of relativistic electron and positron fluids, alongside an inertial nonrelativistic ion fluid, such as helium. By employing a higher-order correction within the reductive perturbation framework, a quartic nonlinear Korteweg–de Vries equation is derived. Solutions to this equation are explored, revealing both stationary soliton and novel periodic oscillatory wave structures. The study finds that factors such as the degenerate pressure, the incorporation of Fermi temperatures, and quantum mechanical effects (driven by quantum diffraction) of the electron and positron species—along with their respective number densities—have a profound impact on the formation and behavior of solitons and periodic oscillatory waves around and at S-CVs. These waves can manifest with positive potentials, depending on the interplay of the plasma parameters. The results provide valuable insights into nonlinear phenomena in astrophysical environments, such as within white dwarfs and neutron stars, as well as in laboratory plasma settings, including intense laser interactions with solid matter.

Isolation and identification of toxins inhibiting Shal potassium channels from the venom of Ornithoctonus hainana spider.

Isolation and identification of toxins inhibiting Shal potassium channels from the venom of Ornithoctonus hainana spider.

The Comprehensive Quantification and Characterization of Oak Biochar Produced via a Gasification Process Using a Downdraft Reactor

This study presents a comprehensive characterization of oak biochar produced via downdraft gasification at 850 °C. The research employs a wide range of advanced analytical techniques to examine the biochar’s physical, chemical, and structural properties. Scanning electron microscopy (SEM) revealed a mesoporous structure, while Brunauer–Emmett–Teller (BET) analysis showed a surface area of 88.97 m2/g. Thermogravimetric analysis (TGA) demonstrated high thermal stability and carbon content (78.7%). X-ray photoelectron spectroscopy (XPS) and ultimate analysis confirmed the high degree of carbonization, with low O/C (0.178) and H/C (0.368) ratios indicating high aromaticity. Fourier transform infrared spectroscopy (FTIR) identified functional groups suggesting potential for CO2 adsorption. The biochar exhibited a negative zeta potential (−31.5 mV), indicating colloidal stability and potential for soil amendment applications. X-ray diffraction (XRD) and Raman spectroscopy provided insights into the biochar’s crystalline structure and graphitization degree. These findings highlight the oak biochar’s suitability for diverse applications, including soil improvement, carbon sequestration, and environmental remediation. By filling knowledge gaps in oak-specific biochar research, this study underscores the benefits of optimized downdraft gasification and sets a foundation for future advancements in sustainable biochar applications.

Folate-targeted pH-sensitive albumin nanoparticles loaded with Baicalin enhance tamoxifen efficacy in estrogen receptor alpha-positive breast cancer.

Folate-targeted pH-sensitive albumin nanoparticles loaded with Baicalin enhance tamoxifen efficacy in estrogen receptor alpha-positive breast cancer.

Polyphosphate as a novel aggregation suppressor of gamma globulin.

Polyphosphate as a novel aggregation suppressor of gamma globulin.

Integrated electrochemical identification and detoxification of chromium oxyanion by dual amino functionalized carboxymethyl cellulose material.

Integrated electrochemical identification and detoxification of chromium oxyanion by dual amino functionalized carboxymethyl cellulose material.

Structural and electrochemical investigation of benzimidazole picolinic acid derivatives for sustainable energy storage applications

Supercapacitors are widely employed in electric vehicles and portable electronics due to their rapid charge–discharge capability, high power density, and energy efficiency; however, many still depend on non-renewable materials. This study reports the synthesis and comprehensive characterization of benzimidazole picolinic acid (BPEP) as a sustainable, high-performance electrode material for supercapacitors. Optical and electrical analyses reveal significant π → π* and n → π* transitions, with prominent UV–visible absorption peaks at 282 nm (experimental) and 294 nm (theoretical). BPEP exhibits excellent light absorption, achieving 99% light-harvesting efficiency at 300 nm and an extinction coefficient of 2250, underscoring its strong optical potential. Frontier Molecular Orbital (FMO) analysis indicates a band gap of 3.9 eV, reflecting notable chemical hardness and thermal stability. Additionally, the negative chemical potential (μ = –4.377 eV) and high electrophilicity index (ω = 5.249 eV) suggest enhanced chemical reactivity and stability that key attributes for energy storage. Electrochemical impedance analysis reveals a maximum specific capacitance of 125.45 F/g at a scan rate of 10 mV/s, confirming efficient charge storage behavior. Vibrational analysis and optimized geometry further affirm the structural integrity of BPEP. Collectively, these results highlight the optical, topological, and electrochemical merits of BPEP, establishing it as a promising eco-friendly candidate for next-generation supercapacitor electrodes.

Periodate oxidation of polysaccharides from Agaricus blazei edible mushroom and their toxicity in adult zebrafish (Denio rerio).

Periodate oxidation of polysaccharides from Agaricus blazei edible mushroom and their toxicity in adult zebrafish (Denio rerio).

Antiviral and anti-inflammatory efficacy of nanoencapsulated brazilian green propolis against SARS-CoV-2

The global COVID-19 pandemic, caused by SARS-CoV-2, continues to pose a significant threat to public health and the economy. SARS-CoV-2 is highly contagious, transmitted primarily through direct contact or inhalation of droplets, and can cause severe respiratory illnesses and other health complications, including post-acute COVID-19 syndrome. This study explored the antiviral potential of Brazilian green propolis, a natural product rich in flavonoids and phenolic compounds encapsulated in a microemulsion, to enhance its stability and antiviral effects. Brazilian green propolis extract was encapsulated in a microemulsion (ME-GP) and characterized using various physicochemical techniques. Furthermore, the antiviral and anti-inflammatory activities of ME-GP was evaluated in vitro and ex-vivo against SARS-CoV-2. For this, cells or tonsils were treated with ME-GP followed by infection with SARS-CoV-2. The microemulsion showed a size of approximately 217 nm, negative zeta potential, high encapsulation efficiency for artepillin C and baccharin (< 99%), and a spherical morphology. The ME-GP formulation was evaluated for antiviral activity against multiple SARS-CoV-2 variants (Wuhan, Gamma, Delta, and Omicron) in Caco-2 cells. The results demonstrated a significant reduction in viral load, particularly for the Wuhan and Delta variants, with up to a 99% reduction in viral load under prophylactic treatment conditions. Time-of-addition assays revealed that ME-GP acts at an early stage in the viral life cycle, likely by interfering with viral entry or immediate post-entry events. Additionally, ME-GP was evaluated in human tonsils, demonstrating an 80% reduction in viral load, suggesting its potential to reduce the transmission and progression of infection. Furthermore, ME-GP exhibited anti-inflammatory activity in human tonsils, significantly decreasing IL-1β, IL-6, TNF-α, and TNF-β levels. Thus, this study highlights the promising prophylactic and therapeutic potential of nanoencapsulated green propolis for combating SARS-CoV-2 and its variants, providing a natural adjunct in COVID-19 therapy.

Intranasal Delivery of Cetrorelix Via Lipid Liquid Crystal Nanoparticles: Characterization and Pharmacokinetic Studies in Rats

Nasal sprays are extensively researched due to their rapid absorption, high bioavailability, and low side effects. Lipid liquid crystal nanoparticles (LLCNs) are being considered as potential carriers for intranasal delivery. LLCs loaded with cetrorelix (GnRH antagonist) were utilized for intranasal drug delivery to enhance brain targeting while minimizing systemic exposure. A single-phase formulation incorporating HPMC as a mucoadhesive was developed to extend nasal residence time. Following intranasal administration of cetrorelix in rats, its distribution in various brain regions and serum was assessed using LC–MS-MS. In the LLC formulation, the particle diameter, PDI, and Zeta potential were measured as 204.92 ± 0.89 nm, 0.188 ± 0.019, and -21.63 ± 1.72 mV, respectively. A monomodal distribution and low polydispersity index were observed, along with a negative zeta potential. Cetrorelix was released from the LLC in a biphasic profile, with an initial burst release of 30%, followed by a gradual and sustained release phase. The LLCs containing cetrorelix exhibited lower cytotoxicity compared to the LLC base. The nasal administration of cetrorelix via LLCs presents a promising advancement for nose-to-brain drug transport. The pharmacokinetic data demonstrated that the AUC0-360min for brain tissue analysis, following nasal administration of the single-phase formulation, was 3.104 ng/ml.min. The value was 7.104 ng/ml.min for LLC nasal administration and 6.104 ng/ml.min for subcutaneous injection. The maximum concentration (Cmax) values for brain tissue analysis indicated a significant increase with LLC nasal administration (238 ± 6. 2 ng/ml) in comparison to the single-phase formulation (202.5 ± 6.3 ng/ml) and subcutaneous injection (218.2 ± 3. 1 ng/ml). In serum analysis, the Cmax values were significantly elevated, with subcutaneous injection achieving (4983.3 ± 2.5 ng/ml), followed by LLC nasal administration at (93.1 ± 6.2 ng/ml), and the single-phase formulation at (43.7 ± 2.2 ng/ml). This innovative method aims to target the brain directly, eliminating the need for needles, and reducing adverse effects, hence offering new hope for brain-targeted drug delivery. This study introduces, for the first time, a cetrorelix-loaded lipid liquid crystal (LLC) nanoparticle formulation for intranasal nose-to-brain delivery. The LLC system achieved enhanced brain targeting efficiency while reducing systemic exposure compared to conventional subcutaneous injections and simple nasal formulations, representing a promising advancement in GnRH drug delivery strategies.Graphical

Modulating Ru-Co bond lengths in Ru1Co single-atom alloys through crystal phase engineering for electrocatalytic nitrate-to-ammonia conversion

Single atom alloys (SAAs) with maximum atomic efficiency and uniform active sites show great promise for heterogeneous catalytic applications. Meanwhile, crystal phase engineering has granered significant interest due to tailored atomic arrangements and coordination environments. However, the crystal phase engineering of SAAs remains challenging owing to high surface energy and complex phase transition dynamics. Herein, Ru1Co SAAs with tunable crystal phases (hexagonal-close-packed (hcp), face-centered-cubic (fcc), and hcp/fcc structure) are successfully synthesized via controlled phase transitions. These SAAs exhibit distinct crystal phase-dependent performance towards nitrate reduction reaction (NO3RR), where hcp-Ru1Co outperforms its counterparts with a NH3 Faradaic efficiency of 96.78% at 0 V vs. reversible hydrogen electrode and long-term stability exceeding 1200 h. Mechanistic investigations reveal that the hcp configurations enables shorter Ru-Co distances, stronger interatomic interactions, and more positive surface potential compared to hcp/fcc-Ru1Co and fcc-Ru1Co, which enhances the NO3− adsorption, reduces the free energy barrier, and suppresses competitive hydrogen evolution.

Cognitive Mechanisms and Temporal Dynamics of Negative Emotion in Facilitating Congruency Judgments.

Cognitive Mechanisms and Temporal Dynamics of Negative Emotion in Facilitating Congruency Judgments.

Impairment of emotional processing from cumulative repetitive subconcussion: Evidence from event-related potentials and sLORETA in parachuters.

Impairment of emotional processing from cumulative repetitive subconcussion: Evidence from event-related potentials and sLORETA in parachuters.

An oxygen-independent therapeutic nanosystem for fighting against hypoxic and antioxidant microenvironment of tumor.

An oxygen-independent therapeutic nanosystem for fighting against hypoxic and antioxidant microenvironment of tumor.

Electrochemical interpretations for the study of molnupiravir binding interactions with bovine serum albumin and DNA and molecular dynamics studies.

Electrochemical interpretations for the study of molnupiravir binding interactions with bovine serum albumin and DNA and molecular dynamics studies.

আত্মচেতনার স্বরূপ : রবীন্দ্রনাথ ঠাকুরের চিঠির পরিপ্রেক্ষিতে

Rabindranath Tagore (1861-1941) produced a remarkably diverse body of literature, much of which is characterized by a tone of joy and celebration. Notably, nearly one-third of his prose writings comprise letters which have been compiled into 19 volumes by the Visva-Bharati Bookstore. These letters offer profound insights into Tagore’s perspectives on society, civilization, literature, education, travel and nature. His reflections emerge at the intersection of introspective Indian idealism and the truth-seeking rationalism of western philosophy. In an age marked by material crises and human deprivation. Tagore’s letters present a vision that inspires resilience and the cultivation of positive human potential. Throughout his life, Tagore remained deeply self-aware, and the consciousness form of ethical and philosophical foundation of writings. It encourages a responsible mode of living in harmony with the natural world. This article aims to explore the thematic elements of self-consciousness, in Tagore’s epistolary works, focusing on four central dimensions; the joy of liberation, the pursuit of truth, spirituality and the appreciation of beauty.

Dampak Tuntutan Perubahan Kurikulum terhadap Kualitas Pendidikan SDN 26 Rimbo Kaluang

Curriculum change is a form of educational innovation aimed at addressing global challenges and local needs. This study seeks to analyze the impact of the transition from the 2013 Curriculum to the Kurikulum Merdeka on the quality of education at SDN 26 Rimbo Kaluang. Employing a qualitative approach with a case study method, the research involved teachers, students, and parents as subjects. Data were collected through interviews, observations, and documentation, and were analyzed thematically. The findings indicate that the implementation of the Kurikulum Merdeka has enhanced student participation and fostered a more interactive and contextual learning environment. Nevertheless, challenges persist, including limited teacher understanding of the new curriculum, students’ readiness to adapt, and low parental involvement. The study concludes that while the Kurikulum Merdeka holds positive potential for improving educational quality, its success depends on systemic preparedness and sustained support. The implications of these findings highlight the need for intensive teacher training, adaptive student support, and strengthened school-parent partnerships to achieve a holistic and sustainable educational transformation.

Preparation of Transparent MTMS/BNNS Composite Siloxane Coatings with Anti-Biofouling Properties

With the rapid development of marine renewable energy, especially offshore photovoltaic systems, the problem of biofouling of photovoltaic equipment in the marine environment has become increasingly prominent. The attachment of marine organisms such as algae will significantly affect the photoelectric conversion efficiency of photovoltaic panels, thereby reducing the stability and economy of the system. In this study, a composite siloxane coating was designed and prepared. Methyltrimethoxysilane (MTMS) was used as the organosilicon component. The negative potential of the coating was significantly enhanced by incorporating hexagonal boron nitride nanosheets (h-BNNS). This negative potential and the negative charge on the surface of marine organisms, especially algae, would produce electrostatic repulsion, which can effectively reduce the attachment of organisms. The results show that the prepared coating exhibits excellent performance in anti-biofouling, adhesion, chemical stability, transparency, and self-cleaning properties. The transparency of the coating reached 92.7%. After immersion with Chlorella for 28 days, the coverage percentage on the coating surface was only 0.98%, while the coverage percentage on the blank sample was 23.25%. The corrosion resistance and salt resistance of the coating also ensure its stability in complex marine environments, and it has broad application prospects.