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2024
- Book : ()
- Pub. Date : 2024
- Page : pp.101817-101817
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2024
Abstract
Context
With the development of urbanization, the spatial and temporal distribution characteristics of the urban landscape pattern play a decisive role in the intensity of the urban heat island (UHI) effect.
Objectives
Most of the current dynamic studies utilizing single cross-section data are labor-intensive and lack continuity.
Methods
A panel data model was constructed to study the relationship between the UHI effect and landscape pattern in Kunming City from four perspectives from 1995 to 2020.
Results
With the passage of time, the UHI is becoming more and more obvious in Kunming. The variables affecting the surface radiation temperature are different at different scales, and the variables affected by increasing scales are increasing. An ordinary least squares (OLS) model was constructed to verify the reliability of the panel data model results. The normalized water body index (NDWI) has the greatest influence on the surface thermal radiance, and the cooling effect is more obvious with the increase in scale. Unlike previous studies, the spatial configuration of the landscape in Kunming City had a stronger effect on the UHI effect than the landscape grouping and vegetation index.
Conclusion
In this paper, the panel data model is introduced into the discussion of UHIs for the first time. It is also found that the construction of relatively shaped and concentrated green space and the breaking up of the aggregation degree of building land patches are the best ways to improve the UHI.- Book : ()
- Pub. Date : 2024
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2024
Geographically, Indonesia is located on the equator, so it is very rich in solar energy sources with an average solar radiation intensity of around 4.8 kWh/m2 per day throughout Indonesia. The main component contained in solar power plants is solar cells which function to convert sunlight into electrical energy This research discusses the Planning of Solar Power Plants for Household Scale Assisted by the PVsyst Program. The purpose of this research is to determine how many solar modules, batteries, solar charger controllers, and inverters are needed for planning solar power plants in households with 900 VA and 1300 VA power. Based on manual calculations and simulations of the PVsyst program, 10 Luxor Ecoline Half Cell 280 Wp polycrystalline modules, 12 Narada EosG 2000 Ah batteries, 1 Victron Energy Mppt 250/100 solar charge controller, and 1 Victron Multiplus Compact 24/1200/25 inverter. The capacity of the solar power plant components for 900 VA and 1300 VA household loads is approximately the same, this is because the average daily energy usage is only slightly different. In 900 VA households, the number of occupants of 6 people uses 7088 Wh/day of energy, while in 1300 VA households with 4 occupants uses 7274.5 Wh/day of energy.- Book : 1(3)
- Pub. Date : 2024
- Page : pp.306-306
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2024
Predicting the process of hydrogen emission from the turbogenerator housing with the formation of flammable hydrogen-air mixtures and flare combustion
The operation of turbogenerators of nuclear and thermal power plants is accompanied by the release of heat, which contributes to the heating of generator components and can lead to an emergency situation (fire). Since As turbogenerators operate for long periods of time, the process of continuous cooling of generator equipment plays an important role, as its overheating can lead to emergency chain reactions, fires, explosions, etc. Analysis of statistical data on the occurrence of emergency situations (fires) related to hydrogen leaks from process equipment indicates insufficient operational qualifications of operational personnel, poor quality of equipment repair, errors of repair personnel and their violation of technical requirements for repairing equipment and their systems, design defects in equipment and systems that ensure its operation. It has been established that the causes of emergency situations are: hydrogen leakage due to leaks in equipment, spontaneous ignition of hydrogen, the presence of air space in turbogenerator equipment, violation of technological regulations, contamination of hydrogen with moisture and pollution, unhermetization of the generator body. Modeling of the hydrogen combustion process during its release from the casing of a turbine-generator was carried out using the example of a power plant engine room. The study showed that the longest hydrogen combustion time will occur when hydrogen is released through holes with geometric size d0 in the range of 0.05--0.1 m (50--100 mm). At larger values of the geometric size of the hole d0 > 0.1 m, the hydrogen burning time is insignificant, and at values of d0 < 0.005 m, the length of the flame burner L does not exceed 1.15 m. The results of the study confirm that hydrogen flame torch combustion can occur as a result of turbogenerator failure. The calculations established the need for fire protection of the supporting metal structures of the engine room to ensure a fire resistance limit of at least 45 minutes under the hydrocarbon curve.- Book : 3()
- Pub. Date : 2024
- Page : pp.109-129
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2024
The tick species that comprise the Amblyomma maculatum group (Acari: Ixodidae) are widely distributed in the Nearctic and Neotropical regions, ranging from the United States of America (USA) to Argentina. This group includes three species: Amblyomma maculatum, Amblyomma tigrinum, and Amblyomma triste, which parasitize a high number of vertebrates, including domestic mammals and humans, where they are the main vectors of Rickettsia parkeri s.s. The identification, distribution, and validity of the three species within the group have been controversial and continue to raise questions. Previous studies have mostly focused on the analysis of partial nuclear and mitochondrial genes, highlighting the need for new integrative analyses that contribute to clarifying their systematics and ecology. In this investigation, we obtained the first mitochondrial genome of A. triste (14,808 bp), which, upon comparison with the reported mitochondrial genomes of A. maculatum, exhibits a genetic distance of 4.2%, providing new evidence for the validity of the former species. The order, composition, and structure of the mitogenome of A. triste are consistent with the characteristics reported for most Metastriata including taxa within Amblyomma, that count with several mitochondrial genomes published in the last few years. The attributes of the mitogenomes, such as the absence of paralogs and a small genome, confirm the utility in studies involving complexes of cryptic species as it also serves as a robust tool for inferring phylogenies. Furthermore, we reported new molecular markers at the mitochondrial level which can be used in phylogenetic studies for other tick species, especially those with controversial or challenging taxonomy. We highlight the need of sequencing the mitochondrial genome of A. tigrinum, which is part of the A. maculatum group, as well as experimental crosses of populations from different places in the Americas to obtain additional evidence for species recognition.- Book : ()
- Pub. Date : 2024
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2024
Abstract:
Secondary neoplasms are a significant cause of mortality among retinoblastoma survivors, particularly when exposed to radiation. This systematic review aims to investigate the association between radiation exposure and the incidence of secondary neoplasms in retinoblastoma survivors. A comprehensive literature search was conducted using PubMed, ProQuest, and EBSCOhost databases to gather relevant studies. Studies written in English about the incidence of secondary neoplasms in retinoblastoma patients who underwent radiotherapy were included. Retinoblastoma patients who did not receive radiotherapy were regarded as the control group. Studies involving animals and those without a control group were excluded. No date restrictions were applied. The last search was performed on April 6, 2022. The study selection process was presented in a flow diagram following the Preferred Reporting Items of Systematic reviews Meta-Analysis 2020 guidelines. The risk of bias was evaluated using the Risk of Bias in nonrandomized Studies of Interventions tool. Statistical analysis was performed using the Cochrane RevMan software (version 5.4.1). Five studies comprising a total of 3324 retinoblastoma patients were included. Of these, 290 (8.72%) patients developed secondary neoplasms, with 250 (86.21%) receiving radiotherapy. The results indicated that retinoblastoma patients who received radiotherapy had a higher risk of developing secondary neoplasms, with a pooled risk ratio of 5.12 (95% confidence interval 3.56–7.36, I
2 = 14%). The findings of this review highlight the importance of considering the risk of developing secondary neoplasms when treating retinoblastoma. Regular medical surveillance for secondary neoplasms should be a standard part of care for retinoblastoma survivors, particularly those exposed to radiation.- Book : ()
- Pub. Date : 2024
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2024
The performance of a Machine Learning (ML) algorithm for chemistry is highly contingent upon the architect’s choice of input representation. This work introduces the partial density of states (p-DOS) descriptor: a novel, quantum- inspired structural representation which encodes relevant electronic information for machine learning models seeking to simulate X-ray spectroscopy. p-DOS uses a minimal basis set in conjunction with a guess (non-optimised) electronic configuration to extract and then discretise the density of states (DOS) of the absorbing atom to form the input vector. We demonstrate that while the electronically-focused p-DOS performs well in isolation, optimal performance is achieved when supplemented with nuclear structural information imparted via a geometric representation. p-DOS provides a description of the key electronic properties of a system which is not only concise and computationally efficient, but also independent of molecular size or choice of basis set. It can be rapidly generated, facilitating its application with large training sets. Its performance is demonstrated using a wide variety of examples at the sulphur K-edge, including the prediction of ultrafast X-ray spectroscopic signal associated with photoexcited 2(5H)-thiophenone. These results highlight the potential for ML models developed using p-DOS to contribute to the interpretation and predic- tion of experimental results made possible by emergent cutting-edge technologies, especially X-ray free electron lasers.- Book : ()
- Pub. Date : 2024
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2024
Abstract
Quantum tunnelling plays a crucial role in heavy-ion fusion reactions at sub-barrier energies, especially in the context of nuclear physics and astrophysics. The nuclear structure of the colliding nuclei and nucleon transfer processes represent intrinsic degrees of freedom. They are coupled to the relative ion motion and, in general, increase the probability of tunnelling. The influence of couplings to nucleon transfer channels relatively to inelastic excitations, on heavy-ion fusion cross sections, is one of the still open problems in this field. We present a new analysis of several systems, based on the combined observation of the energy-weighted excitation functions Eσ in relation to their first energy derivatives d(Eσ)/dE. The relation between d(Eσ)/dE and Eσ removes the basic differences due to the varying Coulomb barrier when comparing different systems. We show that, depending on the nuclear structure and/or the presence of strong transfer channels, this representation reveals characteristic features below the barrier. The possible presence of cross section oscillations makes this analysis less clear for light- or medium-light systems.
PACS Numbers: 25.70.Jj, 24.10.Eq- Book : ()
- Pub. Date : 2024
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2024
Optical methods and optical properties are usually used to research the structure of wood and its ring structure. However, these properties are not directly related to its mechanical and other physical characteristics. To study them, methods of x-ray densitometry, synchrotron radiation, nuclear magnetic resonance, etc., which are not very common in wood science, are used. These methods are quite labor-intensive and require expensive equipment. In this regard, there is a need to develop simple and convenient means and methods for studying the micromechanical properties of wood. The main goal of the work is to develop such an approach using nanoindentation and digital scratching of a cross section of wood and to identify its potential in the further development of dendrochronology and related disciplines. Using the NI method, radial dependences of hardness H and Young's modulus E were obtained for eleven consecutive annual pedunculate oak (Quercus robur L.) wood rings for 3 different loads Pmax = 2, 100 and 500 mN. The values of H in the range from 70 to 340 MPa and Young's modulus E in the range from 2 to 10 GPa were determined for the corresponding loads and early (EW) and late wood (LW). Using the scratch test method, profiles of the normal force Fn and the corresponding hardness HS (in the range from 53 to 225 MPa) were obtained for the period 2007-2020. According to both methods, the widths of annual rings were determined; the discrepancy between the values and the optical method was < 3 %.- Book : 13(4)
- Pub. Date : 2024
- Page : pp.40-57
- Keyword :
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2024
ABSTRACTHere we report the first characterization of the effects resulting from the manipulation of Soluble-Lamin Associated Protein (SLAP) expression during mammalian brain development. We found that SLAP localizes to the nuclear envelope and when overexpressed causes changes in nuclear morphology and lengthening of mitosis. SLAP overexpression in apical progenitors of the developing mouse brain altered asymmetric cell division, neurogenic commitment and neuronal migration ultimately resulting in unbalance in the proportion of upper, relative to deeper, neuronal layers. Several of these effects were also recapitulated upon Cas9-mediated knock-down. Ultimately, SLAP overexpression during development resulted in a reduction in subcortical projections of young mice and, notably, reduced their exploratory behavior. Our study shows the potential relevance of the previously uncharacterized nuclear envelope protein SLAP in neurodevelopmental disorders.- Book : ()
- Pub. Date : 2024
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