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Analysis of Microbial Contamination Test on Ethanol Extract of Mango Mistlettoe
No full textThe mango parasitic plant (Dendrophthoepentandra (L.) Miq) is a semi-parasitic plant that contains bioactive compounds, including flavonoids, tannins, and alkaloids, making it a potential ingredient in herbal drinks. However, because it is derived from natural ingredients, this plant extract is susceptible to microbial contamination, which can affect product quality and safety. This study aims to quantify microbial contamination in ethanol extracts of mango parasitic plant leaves in accordance with the Food and Drug Monitoring Agency (BPOM) Standard Number 29 of 2023. This study employed a quantitative descriptive method; the resulting extract was tested to determine the Total Plate Count (TPC) as an indicator of microbial contamination and the Yeast Mold Count (YMC) as an indicator of mold and yeast contamination. The results showed a TPC of 6,06 × 103 colonies/g and a YMC of 2,9 × 102 colonies/g; both remained below the BPOM maximum limit. These findings support the use of mango mistletoe extract as a raw material for herbal drinks and provide the basis for further research on the safety and quality of herbal products derived from this plant extract
Research on carbon emission baselines of office buildings in hot-summer and cold-winter regions
No full textBuilding operational carbon emissions constitute a critical frontier for achieving the “dual carbon” goals. This study utilizes monthly electricity consumption data from 815 office buildings in hot-summer and cold-winter regions spanning 2021-2023. By integrating operational data with emission factor methodology, we calculated operational carbon intensity, analyzed temporal variations and structural characteristics, and established annual baseline emission benchmarks. Key findings reveal: 1) The carbon intensity of different types of office buildings shows a converging trend, with overall energy efficiency levels being comparable and no significant differences; 2) A significant negative correlation exists between carbon intensity and floor area, accompanied by scale effects and carbon rebound in mega-structures. The developed baseline framework provides quantitative foundations for regional carbon quota allocation, energy efficiency management, and prioritization of energy-saving retrofit initiatives
Analysis and Optimization Strategies for the Summer Indoor Thermal Environment of Existing Rural Houses in Relocated Rural Settlements
No full textThe thermal performance of buildings in relocated rural settlements is closely associated with the enhancement of residents’ living quality and the attainment of the Sustainable Development Goals (SDGs). This study investigates Zhufang New Village in Nanchang City, Jiangxi Province, utilizing a multi- dimensional analytical framework that integrates climatic conditions, spatial morphology, architectural layout, and construction methodologies. Field investigations and empirical data analysis were conducted to analyze the summer thermal performance of representative rural houses, with the objective of elucidating heat transfer mechanisms and identifying key limiting factors. Drawing upon these findings, targeted optimization strategies for thermal performance were formulated. The findings reveal that: (1) Disruptions in hygrothermal regulation substantially degrade the indoor thermal environment, as evidenced by mean temperatures (29.9℃) that surpass the upper limit of the national standard by 1.9℃. The peak temperature recorded on the second floor (31.2 °C) approaches the thermal tolerance threshold (33 °C), while spatial thermal comfort compliance ratios demonstrate marked spatial variability; (2) Interfacial thermal bridging and asymmetrical heat flux distribution generate dynamic thermal stresses. Temperature differentials (ΔT ≥ 2.3 °C) are observed at the roof-balcony junction, whereas radiative heat gain through the east wall produces a daily temperature fluctuation of 4.1 °C. The implementation of thermal inertia mechanisms effectively mitigates humidity oscillations within ±8%; (3) Validation through a climate-adaptive model (25.6–27.6 °C) demonstrates that enhancements to roof U-values, enclosed balcony reconstructions, and composite structural modifications to the east wall achieve a significant reduction in temperature amplitude and an increased proportion of thermal comfort hours
Study on the difference of air flow organization in exhibition halls of archives in Beijing
No full textIn recent years, with the increasing frequency of archive exhibitions held by comprehensive archives at all levels, the people-centered archival service philosophy has taken root in people's hearts. Conducting empirical research on airflow organization in archive exhibition halls can provide research methods and foundational data support for the design of airflow organization in exhibition halls during the construction of archives. This paper compares and analyzes the actual measurement data of airflow organization in the exhibition hall of an archive in Beijing during winter, revealing that the overall visitor route and design of the exhibition hall are relatively complex. The internal structure and space design struggle to achieve uniform symmetry, and asymmetrical structures lead to deviations in internal temperature uniformity. Moreover, when the secondary detailed design of the exhibition hall is carried out, there is no corresponding adjustment in equipment configuration for airflow organization and humidity control, resulting in uneven distribution of temperature and relative humidity. To address these issues, it is proposed to strengthen the setting of temperature and humidity control values for different control systems, adopt dual-system control with separate regulation to maintain consistent greenhouse and humidity ranges across different systems, better meet the needs of different spaces, improve the uniformity of temperature and humidity, and reduce the differences in airflow organization among various areas within the exhibition hall
Spots Identification of Natural Erosion for Hakka Rammed Earth Building: Zhang Bishi Residence Case in China
No full textThe Hakka earth-rammed enclosed-dragon house, a distinctive architectural heritage in Lingnan region, holds immense conservation value. However, it faces numerous challenges from natural degradation and restoration complexities. This study analyzes the natural influencing factors, noting that in Lingnan, with small temperature variations, wind, rain, and solar radiation are the primary factors affecting its conservation and restoration. Using Rhino and Grasshopper, the paper analyzes wind and solar exposure conditions of Zhang Bishi’s Residence, a representative case study. The simulation results align with field observations and scholarly findings, revealing that areas exposed to high wind speeds and low solar radiation suffer more severe deterioration. In contrast, the rear parts of the courtyard—shielded from wind and better lit—experience less damage. The study identifies varying degrees of natural wear across different orientations of the structure, highlighting the need for targeted protection. Based on these insights, the paper proposes a comprehensive conservation strategy from four perspectives: material composition, construction techniques, external protective measures, and long-term maintenance. This research offers a rapid, data- supported diagnostic approach for preserving rammed earth structures in humid climates and contributes theoretical and practical value to their sustainable conservation and cultural inheritance
Controlled stochastic processes for simulated annealing
No full textSimulated annealing solves global optimization problems by means of a random walk in a cooling energy landscape based on the objective function and a temperature parameter. However, if the temperature is decreased too quickly, this procedure often gets stuck in suboptimal local minima. In this work, we consider the cooling landscape as a curve of probability measures. We prove the existence of a minimal norm velocity field which solves the continuity equation, a differential equation that governs the evolution of the aforementioned curve. The solution is the weak gradient of an integrable function, which is in line with the interpretation of the velocity field as a derivative of optimal transport maps. We show that controlling stochastic annealing processes by superimposing this velocity field would allow them to follow arbitrarily fast cooling schedules. Here we consider annealing processes based on diffusions and piecewise deterministic Markov processes. Based on convergent optimal transport-based approximations to this control, we design a novel interacting particle-based optimization method that accelerates annealing. We validate this accelerating behaviour in numerical experiments
Structural inheritance within the outer zones of arcuate collisional orogens: A case from the Central-Northern Apennine orogenic system
No full textThe evolution of fold-and-thrust systems developed at the expenses of pre-orogenic extensional basins is mainly achieved by reactivation, truncation of precursor structures, or by variable combination of these two distinct modes of propagation of compressional deformation during positive tectonic inversion. An overview of three selected examples from the Central-Northern Apennines of peninsular Italy towards the nearby Adriatic foreland domain illustrates that reactivation, truncation or combinations of these two processes of precursor fault deformation tend to be dominant proceeding from forelands towards orogenic interiors, suggesting a correlation between modes of deformation during inversion and their spatial distribution across orogenic belts
The LEGA-C galaxy survey: Multiple quenching channels for quiescent galaxies at
No full textAims. We analyzed the sizes and star formation histories (SFHs) of 2908 galaxies with M★ ≥ 109 M⊙ at 0.6 < z < 1.0, drawn from the Large Early Galaxy Astrophysics Census (LEGA-C) survey. The goal is to investigate the connection between galaxy sizes with SFH, stellar age, and metallicity.
Methods. The SFHs were derived with Prospecto
Centrally concentrated star formation in young clusters
No full textThe study of star cluster evolution necessitates modeling how their density profiles develop from their natal gas distribution. Observational evidence indicates that many star clusters follow a Plummer-like density profile. However, most studies have focused on the phase after gas ejection, neglecting the influence of gas on early dynamical evolution. We investigate the development of star clusters forming within gas clouds, particularly those with a centrally concentrated gas profile. Simulations were conducted using the Torch framework, integrating the FLASH magnetohydrodynamics code into AMUSE. This permitted detailed modeling of star formation, stellar evolution, stellar dynamics, radiative transfer, and gas magnetohydrodynamics. We study the collapse of centrally concentrated, turbulent spheres with a total mass of 2.5 × 103 M⊙, investigating the effects of varying numerical resolution and star formation scenarios. The free-fall time is shorter at the center than at the edges of the cloud, with a minimum value of 0.55 Myr. The key conclusions from this study are: (1) the final stellar density profile is more centrally concentrated than was analytically predicted, reflecting the role of global gas collapse and feedback; (2) subclusters can initially form even in centrally concentrated gas clouds; (3) gas collapses globally toward the center on the central free-fall timescale, contradicting the assumption in analytical models of local fragmentation and star formation; and (4) the mass of the most massive star formed is directly correlated with the cluster effective radius and inversely correlated with the velocity dispersion, while the duration of star formation correlates with the star formation efficiency
Paleogeomorphology of Kulon Progo during the oligocene-early miocene
No full textExploration of natural resources in the Kulon Progo dome often faces obstacles. This is because the paleogeomorphological and stratigraphic dynamics of the region are not yet understood, including stratigraphic relationships at the same time but having different stratigraphic contact forms, as happened in the Oligocene - Early Miocene. At that time, two different stratigraphic contacts were formed, first the unconformity contact between the OAF and the Jonggrangan Formation above it, and the conformity contact between the OAF and the Sentolo Formation. Stratigraphic contact between the Jonggrangan Formation and the Sentolo Formation itself cannot be found. This study aims to provide an overview of what actually happened in the Late Oligocene to Early Miocene, including the paleogeomorphology of the basin and its stratigraphic succession. The research was conducted using a field investigation method on the stratigraphic contacts of OAF-Jonggrangan Formation, and OAF-Sentolo Formation, field data were then analyzed in the laboratory including rock age and depositional environment. The results show that the Jonggrangan Formation is formed in a basin that is not integrated with the Sentolo Formation. Both are limited by a height in the form of an active volcano until the Early Miocene