Oral Category 4 Abstracts

In this paper, we investigate the statistical properties such as probability density function and correlation of the speckle field produced by illuminating Laguerre-Gaussian (LG) beams onto a ground glass. The LG beams, with different topological charges ℓ, are generated using a spatial light modulator (SLM) and transmitted to the ground glass. The ground glass is rotated from  to  in increments of   using a computer-controlled rotational stage.  The probability density function tells us whether the speckles are fully developed or not, while the correlation function indicates the presence of optical memory between speckles. Results show that for topological charges from  to , speckles are not fully developed with leftward shift in their peak values. This shift is due to the expanding dark region and decreasing amplitude at the center as the topological charge  increases. Furthermore, we examine the correlation between speckles and observe an analytical trend in which the optical memory decreases as the topological charge  increases. This behavior can be attributed to the additional phase factor introduced by the Laguerre-Gaussian beam. As  increases, the associated phase structure becomes more complex, introducing greater randomness into the speckle field. This increased phase complexity enhances the occurrence of random constructive and destructive interference, thereby reducing the correlation between speckle patterns and leading to a decline in optical memory. These findings may be of interest for a range of applications that rely on the statistical properties of speckle.

This study employs the White Noise Analysis (WNA) framework to investigate the Aharonov-Bohm (AB) effect in a bound state. We demonstrate that, even in the presence of the AB potential and irrespective of winding, the magnitude of the conjugate momentum for a charged particle in a bound state is conserved. This phenomenon is attributed to the conservation of the system's total angular momentum. While quantum mechanics, particularly the quantization of energy, might suggest otherwise when winding is considered, our findings reveal that conservation of the conjugate momentum magnitude is a fundamental condition for the propagator to satisfy the corresponding Schrödinger equation.

A key insight is that winding does not directly influence the likelihood of detecting the charged particle with a specific momentum at a later time within the AB potential. This implies that the AB effect, despite altering detection probabilities via the magnetic flux, does not disrupt the system's fundamental angular momentum conservation. We further explain that the inability to incorporate winding number information into the momentum-space propagator stems from the Heisenberg uncertainty principle. Our WNA approach thus validates the physics of the bound state AB effect with constant radius and magnetic flux, offering a basis for future experimental designs. We also developed an alternative WNA-based mathematical model to approximate the AB effect and derived a Kuramoto model to describe the phase dynamics of the bound state quantum system, examining synchronization and the magnetic field zone's influence.

This study employs the White Noise Analysis (WNA) framework to investigate the Aharonov-Bohm (AB) effect in a bound state. We demonstrate that, even in the presence of the AB potential and irrespective of winding, the magnitude of the conjugate momentum for a charged particle in a bound state is conserved. This phenomenon is attributed to the conservation of the system's total angular momentum. While quantum mechanics, particularly the quantization of energy, might suggest otherwise when winding is considered, our findings reveal that conservation of the conjugate momentum magnitude is a fundamental condition for the propagator to satisfy the corresponding Schrödinger equation.

A key insight is that winding does not directly influence the likelihood of detecting the charged particle with a specific momentum at a later time within the AB potential. This implies that the AB effect, despite altering detection probabilities via the magnetic flux, does not disrupt the system's fundamental angular momentum conservation. We further explain that the inability to incorporate winding number information into the momentum-space propagator stems from the Heisenberg uncertainty principle. Our WNA approach thus validates the physics of the bound state AB effect with constant radius and magnetic flux, offering a basis for future experimental designs. We also developed an alternative WNA-based mathematical model to approximate the AB effect and derived a Kuramoto model to describe the phase dynamics of the bound state quantum system, examining synchronization and the magnetic field zone's influence.

Predicting the intrinsic and extrinsic stability in low-dimensional hybrid organic-inorganic tin halide perovskites is a critical challenge, requiring a thorough understanding of the material and environmental parameters that govern their degradation. The research was conducted using a data-driven approach, integrating materials informatics with machine learning techniques. This involved developing a comprehensive dataset of hybrid organic and inorganic perovskite properties relevant to stability from various repositories. Recursive feature elimination is then used to obtain the necessary features for training the model. Furthermore, various machine learning models, including Random Forest and Support Vector Machines, were developed and applied to predict their intrinsic and extrinsic stability. It was confirmed that the organic cation at the A site of the perovskite plays a crucial role in its intrinsic stability. Specifically, the cation dictates the dimensionality, interlayer interaction and hydrophobicity. The model also achieved satisfactory results at above 80% accuracy in predicting the formation energies of difference perovskite. As validation for the result of the model, standard density functional theory methods were used. Regarding extrinsic factors, the model is providing insights in determining the factors connected to the performance stability of the perovskite. These findings offer a data-driven guide for the design of stable low-dimensional perovskite materials, crucial for advancing their practical application in photovoltaic devices.

We present a search for axion-like particles (ALPs), hypothetical pseudo-scalar bosons predicted by extensions of the Standard Model that address the strong CP problem and serve as potential dark matter candidates. This study is motivated by theoretical scenarios in which the mass of axions may vary over time due to environmental or cosmological factors. We analyze ultra-peripheral lead–lead (Pb–Pb) collision data recorded by the LHCb experiment, focusing on the dimuon final state as a possible decay channel of axion-like particles.

In this analysis, the signal is modeled using a Gaussian probability density function in the dimuon invariant mass distribution, with a time-dependent mean to capture potential mass variation, and a fixed width of 10 MeV. The time dependence is incorporated using a step function, where the width corresponds to the duration of a run, and the height is proportional to the number of J/ψ candidates in that run divided by the total number of J/ψ times the run duration. This construction reflects the relative statistical weight of each time segment based on event yield and run length.

No statistically significant deviation from the background-only hypothesis is observed. We therefore set upper limits on the cross section times branching ratio as a function of the axion mass.

We proposed a device that uses an applied voltage to control the reflection of a light beam by using a phenomenon called the Goos-Hänchen (GH) shift. This occurs when a light beam's angle of incidence and reflection differs or when the reflected beam is displaced laterally relative to the plane of incidence. For the case where an intermediate layer is formed, the calculations suggest that we could control the reflected light beam, as shown below, since the depletion region depends on the applied voltage. 

However, from the results, the relationship between the GH shift and the applied voltage is not linear. Being able to master these parameters, we could control light beams without utilizing mechanically controlled mirrors. This enables us to conduct ultra-precise measurements and inertia-free optical control. 

Figure 1. AFM topography of (a) pristine carbon SPE and (b) phage-modified carbon SPE

A label-free technique for the rapid detection of the foodborne pathogen Listeria monocytogenes in RTE meat buffer extracts was developed using novel biorecogntion elements- bacteriophages. This study reports the development of an impedimetric biosensor using screen-printed carbon electrodes covalently modified with locally isolated bacteriophage lv-BEATS11 for the highly selective capture and detection of Listeria monocytogenes. This biosensor demonstrated a sensing performance based on EIS, where increase in the interfacial resistance (Rct) is correlated to Listeria concentration from 102.5 to 107 CFU/mL. Morphological change confirmed modification of pristine carbon electrodes through SEM micrographs and in-situ surface topography maps. The phage-based biosensor exhibited a rapid response, with maximal surface impedance achieved after only 10 minutes of host incubation, outperforming other biosensors that require longer incubation times. Quantitative analysis showed robust analytical features indicating a limit of detection of 2 CFU/mL and high selectivity with no significant reponse to non-target pathogens Salmonella enterica and Staphylococcus aureus (p>0.05, n=3) It demonstrated stability for up to 2 weeks promoting low-cost sensing as a non-disposable sensor. Applicability of the phage-based biosensor to artificially spiked ham buffer extracts show good recovery rates of 95.5% and 105.2% for 4.5 and 5.5 log CFU/mL, respectively, and 104.4% and 101.4% for 4.5 and 5.5 log CFU/mL for salami samples. This demonstrated the feasibility of the biosensor for its applicability in food monitoring to meet the needs of food industry for the rapid detection of foodborne pathogens.

Figure 1. Specific capacitance of pristine MOFs with 20:70:10 slurry ratio

Figure 1. Schematic Diagram of the Mie LIDAR system developed in this study.

Figure 1. Schematic Diagram of the Mie LIDAR system developed in this study.

Petrography is a fundamental technique used in geology to identify minerals where thin sections are examined under the microscope. To bring out not readily observable features, samples can be further etched or stained. Depending on the opacity of the mineral, the light used can either be transmitted through or reflected by the sample. Ore mineral petrography utilizes reflected light, but identification is often challenging given that many ore minerals have similar muted colors. For example, copper sulfosalts like enargite-luzonite (Cu3AsS4) and tennantite (Cu12As4S13) are both gray with slight pink and green tinges, respectively. To an untrained eye, distinguishing between the two may prove to be difficult.

This study employs petrography, mineral chemistry, and diagnostic leaching to observe and verify the potential of sodium hydrosulfide (NaHS) as an etching agent for copper sulfosalts. Samples were obtained from the Carmen epithermal deposit in Mankayan, Benguet and contain both enargite-luzonite and tennantite. Polished slabs were prepared and leached in a NaHS solution for a total of 12 hours, observing the progression of its effects every two hours. Results show significant differences in the appearance of enargite-luzonite compared to tennantite. Under the microscope, microstructures like grain boundaries and cleavage in enargite-luzonite are now visible while tennantite remains unchanged, homogeneous, and massive. Additionally, polysynthetic twinning in luzonite is also exposed, providing further distinction from enargite. These were verified by mineral chemistry analysis using electron dispersive spectroscopy (EDS).

This highlights the suitability of NAHS as an etchant for distinguishing enargite-luzonite from tennantite under reflected light.

As consumers seek healthier foods, tablea—a 100% cacao product—gains appeal for its theobromine and antioxidant-linked health benefits like heart and mood support. This study investigated the effects of the cacao bean fermentation on the bioactive compounds, sensory preference, and consumer willingness to pay (WTP) of tablea to identify the optimal fermentation time for its health and market value. Cacao beans were subjected to 0, 2, 4, 6, and 8 days of fermentation. The tablea produced from different fermentation time were analyzed for its physico-chemical content, theobromine content, total phenolic content (TPC), and antioxidant activity. Results revealed that pH significantly decreased indicating increase in acidity and flavor development, and moisture content significantly decreased indicating influence of fermentation in product stability that aligns with the standard.  Water activity remained unaffected with all values within the acceptable range (0.51–0.56). Theobromine content exhibited fluctuations, while both TPC and antioxidant activity declined at longer fermentation periods. The sensory attributes of the resulting tablea were evaluated and results indicate that aroma was significantly enhanced at Day 8, though other sensory attributes were not significantly affected. A consumer survey assessed factors affecting WTP for tablea using an ordered probit regression model. Results show that consumers who perceived tablea as healthy and noticed fermentation-related logos were likely to pay above the suggested retail price.  Over-all findings suggest that 4 to 6 days of fermentation optimally balanced quality and biofunctionality in tablea. Strategic health and fermentation-focused labeling may enhance market acceptance and consumer WTP for tablea. 

Figure 1. Deuterium-tritium fusion reaction.

Figure 1. CLAS experimental data of Σπ invariant mass distributions.

This study aims to characterize a benchtop kilovoltage X-ray irradiator to assess the viability loss in HL60 cells following low-dose X-ray exposure. The study evaluated time-dose linearity and repeatability, dose uniformity, and the impact of cell culture flask on dose delivery. 

Characterization used the 40 kV setting with tube currents: 0.1, 0.2, 0.4, and 0.7 mA. Measurements were obtained using an external Farmer-type ionization chamber. Dose linearity and repeatability were assessed with respect to irradiation time. The T25 flask’s impact on dose delivery was evaluated, and correction factors were calculated. Dose uniformity was evaluated along the central vertical (chamber wall to door) and horizontal (cathode to anode) axes. 

At 40 kV, the slope-based dose rates were 0.006471±1.6E-5 Gy/min (0.1 mA), 0.01454±2E-5 Gy/min (0.2 mA), 0.03062±3E-5 Gy/min (0.4 mA), and 0.05497±7E-5 Gy/min (0.7 mA). A 2% dose uncertainty was achieved with 30 s irradiation, decreasing with longer exposures. Using the slope-based dose rates, dose verification confirmed acceptable uncertainty (<±5%) for ≥22 s. Only 40 kV at 0.1 mA (0.76%) and 0.2 mA (1.0%) settings reliably delivered 0.01 Gy. Dose generally decreased with distance from the field center, with observed asymmetry along the horizontal axis. The 40 kV beam’s half-value layer was 0.77 mm-Aluminum. 

HL60 cells were irradiated with doses from 0.01 to 1 Gy at 0.01454 Gy/min. A dose-dependent decrease in cell viability was observed, with a statistically significant reduction at even the lowest dose of 0.01 Gy (91.6 ± 1.0%) compared to the sham-irradiated cells (93.8 ± 1.3%), 72 hours post-irradiation. 

This study demonstrated the feasibility of using the X-ray irradiator for low-dose irradiation of cells. Results showed that the irradiator can deliver temporally linear, repeatable doses at low rates, with improved accuracy and precision at longer exposures. Correction factors effectively minimized dose discrepancies introduced by the polystyrene T25 flask. Additionally, dose uniformity was influenced by the anode heel effect and the inverse square law. Turntable rotation is recommended to improve uniformity in multi-flask setups.

This study aims to characterize a benchtop kilovoltage X-ray irradiator to assess the viability loss in HL60 cells following low-dose X-ray exposure. The study evaluated time-dose linearity and repeatability, dose uniformity, and the impact of cell culture flask on dose delivery. 

Characterization used the 40 kV setting with tube currents: 0.1, 0.2, 0.4, and 0.7 mA. Measurements were obtained using an external Farmer-type ionization chamber. Dose linearity and repeatability were assessed with respect to irradiation time. The T25 flask’s impact on dose delivery was evaluated, and correction factors were calculated. Dose uniformity was evaluated along the central vertical (chamber wall to door) and horizontal (cathode to anode) axes. 

At 40 kV, the slope-based dose rates were 0.006471±1.6E-5 Gy/min (0.1 mA), 0.01454±2E-5 Gy/min (0.2 mA), 0.03062±3E-5 Gy/min (0.4 mA), and 0.05497±7E-5 Gy/min (0.7 mA). A 2% dose uncertainty was achieved with 30 s irradiation, decreasing with longer exposures. Using the slope-based dose rates, dose verification confirmed acceptable uncertainty (<±5%) for ≥22 s. Only 40 kV at 0.1 mA (0.76%) and 0.2 mA (1.0%) settings reliably delivered 0.01 Gy. Dose generally decreased with distance from the field center, with observed asymmetry along the horizontal axis. The 40 kV beam’s half-value layer was 0.77 mm-Aluminum. 

HL60 cells were irradiated with doses from 0.01 to 1 Gy at 0.01454 Gy/min. A dose-dependent decrease in cell viability was observed, with a statistically significant reduction at even the lowest dose of 0.01 Gy (91.6 ± 1.0%) compared to the sham-irradiated cells (93.8 ± 1.3%), 72 hours post-irradiation. 

This study demonstrated the feasibility of using the X-ray irradiator for low-dose irradiation of cells. Results showed that the irradiator can deliver temporally linear, repeatable doses at low rates, with improved accuracy and precision at longer exposures. Correction factors effectively minimized dose discrepancies introduced by the polystyrene T25 flask. Additionally, dose uniformity was influenced by the anode heel effect and the inverse square law. Turntable rotation is recommended to improve uniformity in multi-flask setups.

Supercapacitors are electrochemical energy storage devices that can be utilized across various fields. Its technological advantages such as high-power density, long-term stability, ease of use, reusability, and fast charge-discharge rates have sparked widespread research interest. In this study, a novel fabric-based electrode is fabricated by integrating polyaniline (PANI), corncob-derived biochar (CCBC), and nickel cobaltite (NiCo2O4) onto a banana-cotton fabric (BCF) substrate. The resulting composite electrode undergoes physicochemical and electrochemical characterizations to evaluate its viability for sustainable energy storage applications. The SEM images of PANI/CCBC/NiCo2O4/BCF at 500x, 1000x, and 2000x magnifications revealed a highly porous architecture and rough surface of the strands. The elemental distribution patterns observed from EDS profile of PANI/CCBC/NiCo2O4/BCF showed the presence of C, N, O, Ni, and Co. FTIR analysis of PANI/CCBC/NiCo2O4/BCF revealed N-H stretching (3200-3500 cm-¹) and C=C/C=N vibrations (1400-1600 cm-¹), confirming PANI’s quinonoid and benzenoid structures, while broad bands at 500-700 cm⁻¹ indicated M–O (Ni/Co) stretching in the NiCo2O4 spinel lattice. PANI/CCBC/NiCo2O4/BCF produced an areal capacitance of 411.22 mF cm-2 (n=3, RSD=20.4%) using CV in a three- electrode setup at a scan rate of 5 mV s-1. And the assembled symmetric CR2032 coin-cell supercapacitor containing the fabricated electrode achieved an areal capacitance of 733.79 mF cm-2 using GCD in a two-electrode setup, and has specific energy of 9.17 Wh kg-1 and specific power of 151.92 W kg-1. Thus, the developed fabric-based electrode emerges as a promising and sustainable material for high-performance supercapacitors.

The growing need for sustainable energy storage, driven by portable electronics and electric vehicles, positions supercapacitors as a key technology in climate- responsive energy systems. This study presents an eco-friendly supercapacitor electrode made from water hyacinth-cotton fabric modified with a polypyrrole/zinc oxide-mung bean shell biochar composite, highlighting local biomass valorization for climate-responsive energy solutions.

Using solvothermal-pyrolysis and in-situ polymerization, the composite was synthesized and integrated into a coin cell. The material’s structure and thermal stability were validated through SEM-EDS, FTIR, XRD, and TGA. XRD confirmed the formation of ZnO nanocrystals in a hexagonal wurtzite phase, while TGA demonstrated stability up to 70°C.

The optimized electrode exhibited a specific capacitance of 365.03 mF/cm² and electrical conductivity of 0.37 S/cm. The assembled coin-cell achieved an areal capacitance of 761.06 mF/cm² at 1 mA/cm², with specific energy and power values of 13.03 Wh/kg and 171.86 W/kg, respectively. Electrochemical impedance spectroscopy revealed low charge transfer resistance, even after 8,500 charge- discharge cycles, with 99% coulombic efficiency and 54% capacitance retention, indicating excellent cycling stability.

The device effectively stored and released solar energy to power a humidity and temperature sensor, demonstrating its potential for off-grid, low-carbon applications. By utilizing abundant agricultural and aquatic waste, this study offers a sustainable and locally relevant solution for energy storage, supporting environmental stewardship and climate resilience in the Philippines.

The canistels (Pouteria campechiana), or tiesa in the Philippines, are characterized by a starchy texture and contain high amounts of nutrients and bioactive compounds, but are currently underutilized.  Moreover, 3D Food printing is a process that forms a figure by depositing food material in a layer-by-layer approach, which offers customization of different food items (Godoi et al., 2016). This study demonstrates the utilization of canistel as an ink for 3D food printing. A screening design using Plackett-Burman design with six variables and 12 runs was done on the formulation of paste ink and 3D food printing. The variables include canistel powder, flour, sodium alginate, printing infill density, printing speed, and printing temperature. The response functions were the moisture content, water activity, color, rheology, shape fidelity of uncooked and cooked samples, visual analysis on uncooked and cooked samples, textural properties and deformation rate. The run 9 with formulation of 32 g of canistel powder, 8 g of flour, 0.5 g of sodium alginate, 40% infill density, 40 mm/s of print, and 40 °C has been the best formulation based on shape fidelity and visual characteristics. Meanwhile,  the screened variables, the most significant are the amount of canistels, the amount of flour, the amount of sodium alginate, and printing speed. The mixture of ingredients significantly affects the shape stability of the 3D-printed snacks. The screened variables needed to be optimized through response surface methodology. Furthermore, the findings show that canistels can be an ink for 3D food printing. 

The occurrence of antimicrobial resistance (AMR), resulting from improper use and handling of antibiotic substances, poses a significant threat to global health, food security, and sustainable development. In veterinary settings, 93,309 tonnes of antibiotics were sold and consumed by the livestock industry, with an expected increase of 11.5% by 2030. Approximately 80.0% of livestock receive antibiotic treatment, and up to 75.0% of these compounds are excreted, eventually entering environmental waters and affecting aquatic biota. In the Philippines, data on antibiotic contamination, particularly in aquatic environments, remain scarce. This study investigates the presence of seven veterinary antibiotics—AMX, AMP, PenG, TET, OTC, SMZ, SMX—in the surface waters of the Pampanga River and its tributaries in Nueva Ecija.

Water samples from various localities were analyzed using a developed LC-MS/MS-ESI- Positive (MRM) method, following an optimized Solid Phase Extraction (SPE) procedure. The method demonstrated high sensitivity with detection limits ranging from 0.046–0.080 ng/mL and recovery values between 63–113%. Five of the seven targeted antibiotics—PenG, TET, OTC, SMZ, SMX—were detected above the established limits, with concentrations ranging from 0.380 to 9.35 ng/mL. SMX was consistently found across all sampled sites, while OTC had the highest concentration (9.35 ng/mL) detected in SC Munoz, where five antibiotics were present.

This study successfully determined the occurrence of veterinary antibiotics through a developed analytical method in surface waters of the Pampanga River and its tributaries. Further studies are recommended to investigate the environmental fate of these substances and assess their ecological impact.

The shift toward sustainable energy has encouraged the investigation of novel materials for advanced energy storage. Among these, two-dimensional (2D) materials have shown great potential as supercapacitor electrodes due to their unique properties. This study focuses on monolayer palladium diselenide (PdSe₂), a 2D semiconductor that shares similarities with graphene. It possesses high electron mobility, high electrical conductivity, and a large surface area per unit mass, making it a strong candidate for supercapacitor applications. To explore further enhancements, the material was modified by introducing point defects through atom vacancies and substitutions with Fe, Co, Cu, or Zn.

Thirteen different systems were modeled, and their formation energies were calculated to assess thermodynamic stability. All vacancy-induced systems showed negative formation energies, suggesting they can form spontaneously. Substituted systems also exhibited low formation energies, indicating that these configurations are energetically feasible. The most stable systems were selected for electronic structure analysis using Bader charge distribution and density of states (DOS). The results revealed that charge accumulation and semiconducting behavior remain consistent even after doping, indicating that the material retains desirable electrical properties after modification.

Quantum capacitance was used as the primary metric to evaluate the effectiveness of the doped PdSe₂ as a supercapacitor electrode. Most modified systems exhibited increased quantum capacitance, with the Se-vacated 1×1 system reaching a peak of  750 μF/cm². This value exceeds graphene-based materials, highlighting its potential in energy storage applications. These findings must be confirmed through experimental studies to support the theoretical predictions.

A deuterium-deuterium (DD) neutron generator (NG) is a promising alternative neutron source for various applications. However, effective shielding for neutrons and photons is essential to protect workers in facilities with DD NG. This study aims to develop a simulation model to evaluate the radiological safety of the planned DD NG facility in the Philippines and ensure compliance with prescribed dose limits. The Monte Carlo-based Particle Heavy Ion Transport Code System (PHITS) was used to model a DD NG facility with a 2.48 MeV source and 10⁸ n/s yield. The ambient dose equivalent rates around the NG were calculated using the PHITS region tally and ICRP 74 flux-to-dose conversion factors. Optimal radiation protection was determined by analyzing various high-density polyethene (HDPE) moderator configurations. Fully shielded, shielded-unplugged, and partially shielded doses are within 5 µSv/hr at 20 mSv/yr occupational dose limits, except at areas around the NG. Unshielded NG exceeds the dose limits inside the facility. The west-oriented fully shielded NG yielded the lowest doses, making it the optimal set-up. With the recommended NG position and shielding configuration, workers can safely operate the NG even with full operating time of 500 hours in a year. Establishing safety boundaries near the source and defining controlled areas are recommended to address the high-dose areas near the NG. This study provides a reference for the radiation safety assessment of the DD NG facility that is being established in the DOST Philippine Nuclear Research Institute.q2

Efficient and reversible hydrogen storage remains a critical challenge in advancing hydrogen-based energy systems. Lightweight carbon nanostructures such as the C₁₂ carbyne ring offer a promising platform but often suffer from hydrogen adsorption energies outside the ideal range (−0.2 to −0.4 eV) for practical storage. Transition metal decoration has been proposed to enhance adsorption through stronger interactions with H₂ molecules.  This study investigates the hydrogen storage capabilities of Ni-, Co-, and Ti-decorated C₁₂ carbyne using Density Functional Theory (DFT). Three adsorption sites were explored: the ring center (hollow site), a C–C single bond, and a C≡C triple bond. For Co and Ti, the hollow site produced adsorption energies within the ideal range, while the single and triple bond sites were less favorable. Ni, by contrast, adsorbed at all three sites but showed adsorption energies outside the ideal range in all cases. The addition of H₂ molecules showed that Co and Ti could adsorb up to 6 and 5 H₂ molecules, respectively, at the hollow site without dissociation, indicating reversible adsorption behavior.  These results highlight the potential of transition metal-decorated carbyne rings, particularly with Co and Ti, as promising nanostructures for hydrogen storage applications.

Gibrat's law posits that city growth rates are independent of their initial sizes. In economic models, this is a necessary condition for the size distribution of cities to follow Zipf's law in the steady state. The latter is a statistical rule where if the sizes of a collection of objects are arranged in descending order, the second is one-half of the largest, the third is one-third, and so on. It is one of the signatures of a complex system.

Using linear and kernel regression approaches, Gibrat's law is tested for Philippine cities and municipalities, collectively termed as local government units (LGUs), with population data taken from the Philippine Statistics Authority census of 2000, 2010, 2015, and 2020. Both parametric and nonparametric methods indicate that the growth rates are not independent of the initial size. The kernel regression approach also reveals that the largest LGUs tend to have above-average growth rates, while the smallest LGUs have below-average rates.

This work presents a green, microwave-assisted strategy to functionalize rice husk-derived lignin with furanic groups for corrosion protection of SUS304L stainless steel. Lignin was extracted using a deep eutectic solvent (DES) composed of choline chloride and p-toluenesulfonic acid, then modified under microwave irradiation. Structural analyses (FT-IR, GPC, pyrolysis-GC/MS) confirmed successful incorporation of oxygenated aromatics and increased molecular weight. Electrochemical tests in 3.5% NaCl showed that functionalized lignin coatings (fRH-L) significantly improved corrosion resistance, lowering current density to 2.7 nA·cm⁻² and achieving 99% inhibition efficiency. Impedance modeling via a CPE-modified Cole-Davidson model revealed enhanced dielectric properties and reduced capacitance. Although degradation occurred after 24 hours, fRH-L coatings retained superior protection compared to unmodified lignin. This study highlights rice husk lignin’s potential as a sustainable, corrosion barrier through synergistic biomass valorization.

Fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET/CT) is useful in the diagnosis and staging of cancer and in monitoring treatment. The principle of optimization in radiation protection requires that the radiotracer dose should be minimized while still maintaining adequate diagnostic quality. This study aimed to optimize FDG dosage using regression analysis and with a Philips Vereos PET scanner.

Existing PET scans were collected from the Philippine General Hospital. The liver signal-to-noise ratio () was measured in each scan. Patient weight, BMI, and  were investigated as predictor variables for PET image signal-to-noise ratio () normalized to scan time and injected dose. Weight alone was found to be the best predictor for the normalized SNR among the variables investigated and was chosen as the basis for FDG dosage. The minimum acceptable  () was subsequently determined in two ways. The first by using the minimum SNR_L measured from the collected samples (). The second by using the minimum acceptable  determined through subjective ratings by nuclear medicine physicians of PET image quality ().

Two separate dosage equations were created using the two  determined. The new dose equation using  would result in dose reduction for almost all sample patients with a mean dose change of -64.21%. Meanwhile, the dose equation with  would still result in dose reduction for most of the sample patients with a mean change in dose of -51.90%. The higher dose may be justified by the improvement in diagnostic confidence and greater clarity of suspicious structures.