Effects Of Expansion Research Articles

Diurnal Asymmetry Effects of Photovoltaic Power Plants on Land Surface Temperature in Gobi Deserts

The global expansion of photovoltaic (PV) power plants, especially in ecologically fragile regions like the Gobi Desert, highlights the suitability of such areas for large-scale PV development. The most direct impact of PV development in the Gobi Desert is temperature change that results from the land-use-induced albedo changes; however, the detailed and systemic understanding of the effects of PV expansion on land surface temperature remains limited. This study focuses on the 16 largest PV plants in the Chinese Gobi Desert, utilizing remote sensing data to assess their effects on land surface temperature. Our result showed a cooling effect during the daytime (−0.69 ± 0.10 °C), but a warming effect during the nighttime (0.23 ± 0.05 °C); the overall effect on the daily mean was a cooling effect (−0.22 ± 0.05 °C). Seasonal variations were observed, with the most significant cooling effect in autumn and the weakest in summer. The PV area was the most significant factor which influenced the temperature variation across PV plants. Our findings enrich our understanding of the environmental effects arising from the construction of PV plants and provide vital information for the design and management of increasingly renewable electricity systems globally.

Optical fiber sensor for curvature and temperature simultaneous measurement based on an anti-resonance mechanism

Based on an anti-resonance mechanism, we propose and experimentally demonstrate an optical fiber sensor for simultaneous measurement of curvature and temperature. The sensor structure consists of a hollow fiber and a twisted graded index multimode fiber spliced between two single-mode fibers. By using the twisted graded index multimode fiber to change the energy distribution of the mode field, not only improve the coupling efficiency of the sensor but also the sensitivity of the curvature measurement. The experimental results show that the intensity of the resonance peak based on the anti-resonance mechanism decreases with the increase of curvature, while the resonance peak wavelength is insensitive to curvature. In addition, due to the thermal expansion and thermo-optic effect of the fiber, the wavelength of the resonance peak is red-shifted with increasing temperature, and the intensity of the resonance peak is insensitive to temperature. Therefore, the intensity and wavelength signals of the resonance peak are monitored separately, and the simultaneous measurement of displacement and temperature is realized. The maximum sensitivity of the proposed curvature sensor can reach −2.84 dB/m−1, the dynamic range of curvature is 0 m−1 to 20.18 m−1, and the temperature sensitivity of 20 pm/∘C is realized. The proposed sensor has a compact structure, simple preparation, high coupling efficiency, and good repeatability, making it an ideal choice for simultaneous measurement of curvature and temperature in structural monitoring, mechanical manufacturing, and other fields.

Examining nonlinear effects of socioecological drivers on urban solar energy development in China using machine learning and high-dimensional data

In the context of carbon neutrality target, renewable energy sources have been transforming from “supplementary energy” to “main energy”, which have promoted the green and low-carbon transition of global energy supply system. In-depth analyzing the spatial patterns and driving mechanisms of renewable energy expansion are of significance for optimizing the spatial layout of clean power, and avoiding the phenomenon of wind and solar power curtailment. In this paper, we proposed an ensemble learning model to examine the nonlinear effects of physical geography, resource endowment, and socio-economic factors on solar photovoltaic (PV) capacity at the prefecture-level city scale in China. Using the city-level multi-sources geospatial big data, we extensively collected a total of 175 related explanatory variables and cumulative installed capacity of solar PV power for 295 prefecture-level cities of China. The recursive feature elimination algorithm (SVM-REF) is firstly used to extract the optimal feature subset of urban PV capacity from multi-dimensional features variables. Furthermore, three advanced machine learning models (random forest, decision tree, extreme gradient boosting) are developed to identify the key influencing factors and nonlinear driving effect of urban solar PV power expansion in China. The results show that China's PV installation capacity is highly concentrated in Northern and Northwest parts of China, with the occupancy over 70% in 2019. Moreover, the XGBoost model has the best prediction accuracy (R2 = 0.97) among three methods. We also found that total amount of urban water resources, average solar radiation, and population density are the most important controlling factors for urban solar PV capacity expansion in China, with contribution of 35.6%, 17.7%, and 13.3%, respectively. We suggested that urban solar PV layout mode in China is recommended to gradually shift from resource orientation to the “resource-environment-demand” comprehensive orientation. The paper provides a replicable, scalable machine learning models for simulating solar PV power capacity at the prefecture-level city scale, and serves as a motivation for decision-making reference of the macro siting optimization and sustainable development of China's green power industry.

Skeletal effects of posterior crossbite treatment with either quad helix or rapid maxillary expansion: a randomized controlled trial with 1-year follow-up

ABSTRACT Objectives To assess skeletal and dental effects and evaluate possible side effects of maxillary expansion with two different appliances, directly after expansion and 1 year postexpansion. Materials and Methods Forty-two patients with unilateral posterior crossbite (mean 9.5 ± 0.9 years) were randomized to either rapid maxillary expansion (RME) banded on the deciduous second molars and bonded to the primary canines or slow expansion with quad helix (QH) on the permanent first molars. Cone-beam computed tomography records were taken at baseline, directly after correction of the posterior crossbite and at follow-up 1 year after expansion. Results All patients were analyzed. RME opened the midpalatal suture more anteriorly and inferiorly (mean 4.1 mm) and less posteriorly and superiorly (mean 1.0 mm). No effect on midpalatal suture could be shown in the QH group after expansion, P < .001. Buccal bone width had significantly decreased (P < .001) in the QH group compared with the RME group. Buccal fenestrations and root resorption on the left first molar had a higher prevalence directly after expansion finished in the QH group (P = .0086, P = .013) but were not significant at 1-year follow-up (P = .11, P = .22). Conclusions Opening of the suture with RME was more anterior and inferior, and the QH did not open the midpalatal suture at all. More buccal bone loss and fenestrations were seen on the permanent first molar in patients treated with conventional QH than RME anchored to deciduous teeth.

Heterogeneous effects of Medicaid expansion on food security measures

AbstractThe 2014 Affordable Care Act (ACA) included state‐level Medicaid expansion programs, which have been credited with gains in food security for low‐income, able‐bodied, childless adults without dependents (ABAWDs). Yet, ABAWDs represent a diverse cohort who experience disparities along racial and ethnic lines, which could be partly responsible for differences in health‐related outcomes. This study uses data from the Current Population Survey Food Security Supplement to estimate the heterogeneous effect of ACA Medicaid expansion on food security among ABAWDs by race, ethnicity, and income. We find that Medicaid expansion improved food security for households headed by White ABAWDs—particularly those with incomes above 50% of the federal poverty line—but we do not find similarly significant evidence of gains among some historically marginalized populations. We find weak evidence that suggests that households headed by Hispanic ABAWDs may have experienced gains. However, Black‐headed ABAWD households had significantly worse food insecurity relative to the pooled sample of all races and ethnicities. Our results suggest that the relationship between healthcare access and food security is complex and, although spillover effects from a change in healthcare policy can influence food security status, such effects may not be equitably distributed across race, ethnicity, or income.

Thermal expansion, lattice vibration, and isotope effect on hydrogen diffusion in BCC Fe, Cr, and W from first-principles calculations.

Fe, Cr, and W are important elements in the alloys of in-reactor materials and operate in high-temperature environments with thermal expansion. Their tritium-impeding abilities are crucial to the radiation safety of various nuclear reactors. In this study, first-principles density functional theory is combined with quasi-harmonic approximation to evaluate factors that can affect the interstitial formation energy and diffusion coefficient of hydrogen isotopes in body-centered cubic (BCC) Fe, Cr, and W, including thermal expansion, metal host lattice vibrations, phonon density-of-states (pDOS) coupling diffusing atoms, and isotope effects. Calculation results indicate that the interstitial formation energy decreases as lattice expansion increases, whereas the jump barriers remain almost constant. Thermal expansion, host lattice vibration, and pDOS coupling minimally affect the diffusion coefficients of hydrogen isotopes in Fe, Cr, and W. The diffusion coefficient ratios between hydrogen isotopes are higher than the inverse ratio of the square root of the isotope mass at low temperatures. However, they decrease to the inverse ratio of the square root of the isotope mass at temperatures exceeding 800K. This study comprehensively investigates factors that affect the diffusion coefficients of hydrogen isotopes in BCC Fe, Cr, and W, thus providing a firm theoretical foundation for predicting the diffusion coefficients of tritium at different temperatures using protium/deuterium diffusion coefficients.

Heterogeneity in crowd‐out by risk aversion: Assessing the effect of the ACA Medicaid expansion

AbstractIn this study, I estimate the heterogeneity in the crowd‐out of private health insurance by risk aversion with the Medicaid expansion under the Affordable Care Act. Using data from the Health and Retirement Study, I find that the Medicaid expansion led to a decrease in private coverage among risk‐loving individuals by 5 percentage points. However, the expansion did not lead to any meaningful change in private coverage for risk‐averse individuals. This finding suggests that risk‐averse individuals are willing to keep their private coverage, even though they become eligible for Medicaid. This potentially signals a sorting effect into private insurance. Under the assumption that highly risk‐averse individuals typically display superior health conditions, this preferential behavior could signify a form of advantageous selection into private insurance. Furthermore, the expansion increased Medicaid coverage by 3.4 percentage points for risk‐loving individuals, while not causing any discernible change in coverage among risk‐averse individuals. Such differential responses could potentially influence the risk composition of Medicaid coverage, and subsequently impact the cumulative expenditure associated with it.

Causes, Impacts, and Historical Analysis of the War of Vietnam

The Vietnam War was one of the most dubious and compelling military conflicts of the twentieth century. This article aims to give a top-to-bottom examination of the causes, effects, and history of the conflict that sawthed in Vietnam from 1955 to 1975. Utilizing essential and optional sources, the creator investigates different parts of the contention, including its set of experiences. the specific situation, the explanations for the episode of the conflict, and the expansive effects that keep on affecting local and worldwide issues right up to the present day. The verifiable setting of the Vietnam War can be traced back to the pioneering time when Vietnam was under French frontier rule. The craving for autonomy and solidarity turned into the focal subject that molded Vietnam’s public character and brought about the different enemies of pilgrim developments. Following the First Indochina War, which saw Vietnam split along the 17th parallel, there were more wars, which eventually turned into the Second Indochina War. The main drivers of the Vietnam War were multi-layered and complex. One of the principal factors is the philosophical hole between the socialist North and the non-socialist South. The Cold War competition between the US and the Soviet Union likewise assumed a significant role, with America supporting the South Vietnamese government to forestall the spread of socialism in Southeast Asia. Additionally, regional dynamics and nationalism play a role in the region’s growing hostility. This segment talks about significant occasions and defining moments during the Vietnam War, including the Inlet of Tonkin occurrence, the Tet Hostile, and the Paris Truce. These occurrences had a significant impact on the course of the conflict and influenced public opinion worldwide as well as in the countries involved

Effect of Slow Maxillary Expansion and Alternative Rapid Maxillary Expansion Protocols on Airway Volume in Cleft Palate Cases: A Cone Beam Computed Tomography Based Study

Effect of Slow Maxillary Expansion and Alternative Rapid Maxillary Expansion Protocols on Airway Volume in Cleft Palate Cases: A Cone Beam Computed Tomography Based Study

D129. The Effect of Medicaid Expansion on Rates of Carpal Tunnel Release: An Interrupted Time Series Analysis

D129. The Effect of Medicaid Expansion on Rates of Carpal Tunnel Release: An Interrupted Time Series Analysis

Incorporation of self-heating effect into a thermo-mechanical coupled constitutive modelling for elastomeric polyurethane

Elastomeric polyurethane (EPU) is characterised by distinctive mechanical properties, including high toughness, low glass transition temperature, and high impact resistance, that render it indispensable in diverse engineering applications from soft robotics to anti-collision devices. This study presents a thermo-mechanically coupled constitutive model for EPU, systematically incorporating hyperelasticity, viscoelasticity, thermal expansion, and self-heating effect in a thermodynamically consistent manner. Experimental data, obtained from previous studies, are then used for parameter identification and model validation, including iterative updates for temperature parameters considering the self-heating effect. Subsequently, the validated model is integrated into finite element codes, i.e., user subroutine to define a material’s mechanical behavior (UMAT) based on the commercial finite element software ABAQUS, for the computation of three-dimensional stress-strain states, facilitating the analysis of the structural response to various mechanical loads and boundary conditions. The results obtained from simulations are compared with analytical solutions to confirm the precision of Finite Element Method (FEM) implementation. The self-heating effect is further analysed under different strain rates and temperatures. To validate the engineering significance of the FEM implementation, a plate with a hole structure is also simulated. In conclusion, this research provides a robust tool for engineers and researchers working with soft materials, enhancing their understanding and predictive capabilities, notably addressing the self-heating effect in thermo-mechanical behaviours.

Nano-silicon embedded in mildly-exfoliated graphite for lithium-ion battery anode materials

Silicon-based materials have a high theoretical specific capacity and a low discharge potential, whereas the significant capacity fading owing to weak conductivity and volume exfoliation effect. The co-utilization of silicon and graphite has become a feasible method for realizing high-performance lithium-ion batteries (LIBs). Herein, the C@p-Si/ESG composite anode material with “sandwich” structure was obtained by electrostatic assembly of mildly-exfoliated graphite and electrostatic modified nano silicon, and subsequent coated with amorphous carbon on the surface of the material. The carbon coating and the mildly-exfoliated graphite form a buffer space, which alleviates the volume expansion effect of silicon in the process of lithium alloying. In addition, the SEI film is generated outside the carbon layer, reducing the consumption of the electrolyte and the occurrence of side reactions. C@p-Si/ESG exhibits a high charge–discharge rate and an excellent long-term cycle stability.

Economic and environmental analysis of Malaysia's 2025 renewable and sustainable energy targets in the generation mix

In pursuing the goals of sustainable development and transiting from fossil fuel-dependent electricity generation to renewable and sustainable alternatives as endorsed by COP28, Malaysia set a 31 % target for renewable-energy in the power generation mix by 2025. This underlines Malaysia's commitment to combat climate change, mainly by reducing its economy-wide GDP carbon intensity by 45 % from the 2005 levels by 2030. To better understand the effects of renewable energy expansion on the economy, environment, electricity output and input-mix, a computable general equilibrium model is applied using an updated benchmark. The simulation results show that increasing the share of coal and gas in the power generation mix compromises emission reduction targets. Further, there is a trade-off between subsidized natural gas supplies and power generation and exports. The results also show that a larger proportion of renewable energy leads to improved welfare. As the share of gas and coal in renewable energy generation is not very high, its impact on carbon emissions is limited. However, if renewable energy expansion is complemented by subsidy rationalizations, the positive impacts are more pronounced. In terms of policy implications, the findings suggest that Malaysia must step up its emission reduction efforts by augmenting the generation of renewable rather than non-renewable resources. Complementary initiatives such as emission abatement policies and consumption subsidies for refined oil products and fossil-fuel power generation should be rationalized to expand renewable resources, improve energy security, and attain emission reductions.

The effect of Medicaid expansion on rates of carpal tunnel release: an interrupted time series analysis.

Medicaid expansion through the Affordable Care Act (ACA) has been associated with greater access and utilization of surgical services in underserved populations. However, its impact on use of hand surgical care is less understood. The purpose of this study was to evaluate the association between New York State adoption of the ACA and carpal tunnel release (CTR) procedural volume in Medicaid beneficiaries. We conducted a pooled cross-sectional analysis of patients who underwent CTR using the Healthcare Cost and Utilization Project New York State all-payer database (2010-2018). An interrupted time series (ITS) analysis using an autoregressive integrated moving average model estimated the immediate and long-term impact of Medicaid expansion in January 2014 on CTR procedural volume in Medicaid beneficiaries and uninsured individuals. A total of 112,569 patients were included in the sample. After expansion, we observed an absolute increase of 6% in the share of CTR procedures provided to Medicaid beneficiaries. Policy implementation was associated with an immediate 1.81% increase (95% CI=0.0085, 0.0277; p<0.001) in the probability of Medicaid as the primary payer and an annual increase of 1.68% (95% CI=0.0134, 0.0202; p<0.001) after reform. ITS analysis found this resulted in 4,190 additional CTR procedures in Medicaid beneficiaries than predicted without expansion. Study results suggest New York's adoption of the ACA was associated with an immediate and steady increase in use of outpatient CTR in Medicaid beneficiaries. Most of this increase represented newly treated patients rather than those who were previously uninsured.

Conjunctive use of floodwater harvesting for managed aquifer recharge and irrigation on a date farm in Morocco

AbstractIn arid regions, harvesting floodwater can mitigate irrigation‐induced groundwater depletion by providing additional surface water and recharging aquifers. We designed an experimental protocol to quantify these fluxes on a date farm located along the Wadi Satt, whose flow originates from the Anti‐Atlas Mountains in south‐eastern Morocco. Automatic barometric sensors were used to monitor the water level in a 6500 m3 floodwater harvesting pond and in surrounding boreholes. Six flood events occurred from 2021 to 2023. The pond water balance indicated that most stored water is pumped for irrigation (56% of harvested floodwater). More than 40% infiltrates at a rate of approximately 90 mm day−1, and the remainder evaporated. Analytical modelling of the pond water table system showed that the radius of the piezometric mound resulting from pond infiltration is less than 360 m. Groundwater recharge from the irrigated plot could be observed after two close floods that enabled continuous pumping for several weeks, suggesting that in this specific context, over‐irrigation using surface water allows the aquifer to be recharged. The hydrological effects of possible future expansion of these ponds at the watershed scale should be analysed to assess possible negative impacts on downstream water resources.

Effects of Rapid Palate Expansion Treatment in Growing Oral Respiratory Patients: Functional Assessment of the Upper Airway Using Active Anterior Rhinomanometry

This retrospective study aims to further investigate the effects of rapid maxillary expansion (RME) treatment on respiratory function in growing patients with contracted upper airways, by assessing nasal resistance using active anterior rhinomanometry (AAR). Methods: At T0 (pre-RME), 122 orthodontic patients aged 5 to 12 years, exhibiting oral breathing and/or snoring along with maxillary contraction, underwent AAR with a mask using the ATMOS Rhino 31 rhinomanometer. Additionally, the SRDB or PSQ-SRDB Questionnaire was utilized to validate the orthodontic history of obstructive sleep apnea syndrome (OSAS). If AAR results at T0 were clinically significant, they were repeated at T1, corresponding to a period of three months after screw fixation, to evaluate changes in nasal resistance values between pre- and post-treatment. Results: The study group comprised 42 oral respiratory patients with a mean age of 7.71 years, suspected of pediatric OSAS. Although the questionnaires did not yield statistically significant results, the therapy induced an overall reduction in airflow resistance values from both nostrils (−24.63% in the right nostril; −26.65% in the left nostril). Conclusions: This study demonstrates the beneficial effects of orthodontic treatment with RME on nasal function in terms of airflow resistance in cases of maxillary contraction.

Trade and Water Pollution: Evidence from China

China’s economy has achieved significant success by integrating itself into the globalized production system over an extended period. However, it is crucial to address the environmental consequences that accompany rapid economic progress. The correlation between trade and environmental pollution is still controversial in the existing literature, with a lack of research specifically investigating this relationship using detailed data at the firm level. Based on the quasi-natural experiment of China’s accession to the WTO, this study uses the DID method to evaluate the causal relationship between trade and the environment experimentally. It is found that trade liberalization significantly increases firms’ industrial wastewater emissions, and the empirical results remain robust after parallel trend tests, placebo tests, and replacement variables. The mechanism of action suggests that trade expansion enhances corporate pollution emissions through two channels: attracting foreign investment into the country and intensifying energy consumption. A heterogeneity analysis reveals that the pollution-enhancing effect of trade expansion on enterprises is mainly concentrated in export-oriented enterprises, labor-intensive industries, and coastal regions. Additionally, further analysis shows that trade liberalization not only has local impacts but also spatial spillover effects on enterprise pollution. It is found that enhancing environmental governance and reducing corruption can effectively mitigate the adverse environmental consequences caused by trade liberalization.

The effects of pterygomaxillary disjunction in surgically assisted rapid maxillary expansion: A systematic review and meta-analysis.

This study aims to assess the expansive effects of pterygomaxillary disjunction (PMD) in surgically assisted rapid maxillary expansion (SARME) surgery using a meta-analysis approach. The study conducted a comprehensive literature search across five databases: PubMed, Scopus, Medline, Embase, and Cochrane, adhering to the PRISMA 2020 guidelines. Dental alterations were assessed using either cone-beam computed tomography (CBCT) or dental casts, while skeletal changes were exclusively measured from CBCT scans. We analysed the dentoskeletal changes between PMD +/- groups and conducted a within-group comparison. The primary focus of the results was on the mean differences observed in pre- and post-operative measurements. Dental expansion was larger in the PMD+ group but not statistically significant. Skeletal expansion showed a significantly larger expansion in the posterior region in the PMD+ group (P = .033). Without PMD, anterior palatal expansion was significantly larger (P = .03), and the buccal tipping of posterior teeth was also significantly larger (P = .011) to achieve acceptable dental expansion outcomes. Both PMD +/- groups of SARME surgery can achieve satisfactory dental expansion outcomes. However, bone expansion and tooth inclination are also important factors that influence orthodontic treatment and post-expansion stability. By reducing the bony resistance with PMD, larger posterior palatal expansion and more parallel bony expansion are observed. In contrast, without PMD, there is smaller palatal expansion and greater tooth inclination in the posterior region. This could potentially lead to compromised periodontal conditions following expansion.

Competition in cargo and passenger between high-speed rail and airlines—considering the vertical structure of transportation

High-speed rail (HSR) services are experiencing rapid global expansion, posing competition not only in the traditional passenger sector but also challenging air cargo with their attributes of speed and punctuality. In this study, we establish a straightforward model for air-HSR competition in both passenger and cargo markets, taking into account the vertical structure of transportation supply chain. We explore various market equilibria based on the combination of three factors: 1) HSR's provision of cargo services, 2) the integration or separation of HSR's ownership and operation, and 3) uniform or differentiated airport administrative fees for passenger and cargo airlines. The analytical results of our model indicate that the entry of HSR into the cargo market consistently enhances social welfare and may even improve the profit of cargo airlines. However, if airports adopt uniform pricing or there is vertical separation in HSR sector, this could potentially weaken the positive impact on welfare enhancement. These findings have important implications for transportation policy, highlighting how strategic management of infrastructure can significantly influence the effectiveness and societal benefits of HSR's expansion into cargo services.

Rice husk waste-derived super-biochar with the max surface area and Philic-CO2 textural structure: Boosting effect and mechanism of post-desilication

A super-carbon material as adsorbents of CO2 were prepared with rice husk waste by a new two-step process, pyrolysis-activation and HF post-desilication process. This paper was focused on investigating the boosting effect and mechanism of post-desilication. It was found that the function of the post-desilication was considerably different from that of the reported pre-desilication. It could not only effectively remove Si element from rice husk biochar (RHC) but also significantly improve its performance, producing a super-biocarbon with a well-developed pore structure, rich C-F groups, and a 4230-m2 g−1 surface area, which is the max surface area of known biocarbon. It could adsorb 341.5 mg g−1 CO2, a max CO2 adsorption capacity of reported biocarbon, and its CO2/N2 and CO2/H2O adsorption selectivity index reached as high as 22.2 and 2.1, respectively. The large surface area was mainly originated from the expansion effect of SiF4 gas from the post-desilication, generating numerous ultra-microspores, while these C-F groups were generated by the co-reactions of the post-desilication. The ultra-high adsorption capacity was mainly from the fill-adsorption driven by the size effect of these ultra-micropores and the strong CO2-affinity of C-F groups, and the adsorption selectivity was confirmed to depend on water-resistant and CO2-philic characteristics of its C-F groups by theoretical calculations and experimental observations. These findings presented not only an advanced CO2-capture material but also a facile way to tailor textural structure of other biochars.