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Search for a shape isomer in
No full textA search for a shape isomer in Th via delayed decay was performed using the Heidelberg–Darmstadt Crystal Ball spectrometer together with a –E telescope for light charged particle identification. Excited states in Th were populated through the Th(d, p) reaction. The search for isomeric decay was based on a total-energy reconstruction method: prompt energy deficits indicated possible long-lived isomeric states. Corresponding delayed summed energies were recorded with the Crystal Ball. A two-dimensional analysis of versus was carried out for various prompt and delayed multiplicities and for delayed time intervals up to 200 ns within the excitation-energy range –7 MeV. No evidence of isomeric decay was observed. The branching ratio for the population of a potential shape isomer in the second minimum of Th relative to the first minimum is constrained to , for isomeric states with energies –4 MeV and half-lives in the range ns–1 s. These results establish stringent experimental limits on the existence and population probability of a second minimum in the potential-energy surface of Th, thereby providing valuable constraints for theoretical models of shape isomerism in actinide nuclei
Astrophysical reaction rates for charged-particle induced reactions on proton-rich nuclides
No full textAstrophysical reaction rates for reactions with proton-rich isotopes of Ne to Bi from stability to the proton dripline were calculated with an updated version of the SMARAGD statistical model (Hauser-Feshbach) code. Here, the focus was on reactions with protons or particles as required for nucleosynthesis in proton-rich matter. For completeness, also neutron-induced reactions are provided for the same set of targets. Some comments on dependencies of rates on various nuclear properties and on the appropriate way to compare to experiments are given. The new rate set for charged-particle induced reactions provides a better description of experimental data than previously widely used rates, especially for reactions involving particles
Regulation of RTE Foods in Indonesia, Singapore, and USA: A Literature Review
No full textFood is a fundamental human right. In Indonesia Law Government Regulation No. 86 of 2019, clasified food into fresh, processed, and Ready-to-Eat (RTE) food. Changes in consumption patterns, particularly in urban areas, have increased RTE food demand. Data from Indonesia Central Bureau of Statistics showed that household spending on RTE foods rose from 25.9% in 2013 to 34% in 2019, the Indonesia Ministry of Health (MoH) recorded 69 food poisoning incidents in 2024 related to RTE products. Similarly, the Singapore Food Agency (SFA) reported 22.5 foodborne illness cases per 100,000 population in 2023–2024, with over half linked to catered foods. In the United States, a 2024 Salmonella outbreak from underprocessed RTE meat caused 104 illnesses and 27 hospitalizations. Given recurring RTE food safety incidents, comparing regulatory frameworks is crucial to identify best practices and policy gaps. This study compared RTE food regulations in Indonesia, Singapore, and the United States. Singapore represents a developed Southeast Asian country, while the United States is a leading voice in global food safety. Through a descriptive review it is shown that Indonesia and Singapore adopt Codex Alimentarius Commission principles in food safety and hygiene. Indonesia focuses on licensing and hygiene certification by the MoH, while Singapore enforces centralized control under the SFA (Singapore Food Agency) with strict microbiological and temperature standards. The United States enforces a preventive, risk-based approach via the FDA (Food and Drug Administration) Food Code and USDA-FSIS (United States Department of Agriculture – Food Safety and Inspection Service). Singapore and the United States show more mature and preventive regulatory frameworks. Therefore, Indonesia needs to strengthen risk-based supervision, hygiene certification, and laboratory capacity
Sustainable biocomposite films from coffee and durian agro-wastes with polyvinyl alcohol matrix
No full textThis study investigated the development of a biocomposite packaging material using coffee bean skin waste, polyvinyl alcohol, and the addition of durian seed starch. The inclusion of cellulose fibers from coffee bean skin waste can enhance the properties of polymeric materials, while PVA can increase the homogeneity and flexibility of the composite sheet. Furthermore, the addition of durian seed starch, which has a high starch content, was explored to reduce water absorption and enhance biodegradation of the biocomposite packaging.The objective of this study was to investigate the impact of varying the PVA to coffee bean skin waste ratio, the glycerol percentage, and the addition of durian seed starch on the tensile strength, elongation, modulus of elasticity, water absorption, and biodegradation of the biocomposite packaging. The selected biocomposite packaging with an additional 20% durian seed starch showed a tensile strength of 10.91±0.36 MPa, elongation of 322.17±17.49%, modulus of elasticity of 3.39±0.21 MPa, water absorption of 104.97±21.32%, and biodegradation based on weight loss of 6.61±0.77% which shows good physical properties. The biocomposite packaging developed in this study demonstrates the potential to utilize waste materials from the food and agriculture industry to create sustainable and biodegradable packaging solutions
Induced and enhanced mesomorphism through intermolecular hydrogen-bonding interactions: influence of rigid core and
No full textA non-mesogenic proton acceptor, viz., (4-pyridyl)-benzylidene-4ʹ-n-heptyl aniline (PyB7A), is prepared and treated with non-mesogenic proton donors, viz., aliphatic and aromatic carboxylic acids, in a 1:1 molar ratio, and their mesomorphism is studied. The non-mesogenic aliphatic acids used are nonyl, undecyl, tridecyl, tetradecyl, hexadecyl and octadecanoic acids which are non-toxic, biodegradable and biocompatible; and the non-mesogenic aromatic carboxylic acids used are x-fluoro/x-chlorobenzoic acids (x is the position of the substituent, x = 2, 3 or 4). The proton donors and acceptors are non-mesogens and are involved in intermolecular hydrogen-bonding (HB) interactions, resulting a smectic mesomorphism. The HBs between the moieties were characterized by Fourier transform infrared (FTIR) spectroscopy. The mesomorphic thermal stabilities of the PyB7A:mA and PyB7A:x(F/Cl)BA HB complexes are discussed in comparison with the similar HB complexes viz., PyB14A:mA; PyB16A:x(F/Cl)BA; PyB16A:nOBA and nOBA dimers. The number of aromatic rings i.e., rigid cores and the π–π interactions in the HB complexes on the induced mesomorphism are discussed. This research supports sustainable production practices, advancing SDG 12
Mesons in nonlocal model with four-dimensional separable kernel
No full textIn this work we study the meson properties in the framework of an effective quark model. We start from the Bethe-Salpeter equation choosing the interaction kernel in nonlocal form with the Gaussian meson vertex function, characterized by a meson size parameter . We demonstrate the model’s predictive power by applying it to both light and heavy systems. Key results include a calculation of the decay width and the pion transition form factor , which reproduces experimental data from low to high . We further predict the electromagnetic properties of heavy quarkonia, obtaining the two-photon decay widths of and and the radiative decay widths of and , all of which show consistency with available data and other theoretical approaches. The model provides a computationally efficient and unified framework for describing mesons from the light to heavy quark sectors
Taming singularities and chaos in conformal gravity
No full textWe hereby address the cosmological singularity problem in a general gravitational theory invariant under Weyl conformal transformations. In particular, we focus on the Bianchi IX spacetime and we show that both the initial (big bang) and final (big crunch) singularities disappear in an infinite class of conformal frames naturally selected according to analyticity. It turns out that the past and future singularities are both unattainable within a finite affine parameter (for massless particles) or within a finite proper time (for massive and conformally coupled particles). In order to prove such a statement, we show the geodesic completion of the spacetime when probed by massless, massive, and conformally coupled particles. Finally, the chaotic behavior of the spacetime near the singularity is tamed by a conformal rescaling that turns the Bianchi IX metric into a quasi-FLRW spacetime
Null reduction and dynamical realization of Carrollian conformal symmetries
No full textWe start from a Lorentzian action in a deformed light-cone background and applying the method of null reduction leads to a Carrollian action in one lower spacetime dimensions. We also identify the correct light-cone definitions of the symmetry generators and their dynamical forms in terms of the fields and take the limit. It is observed that these generators produce the known kinematic Carrollian conformal algebraic commutation relations