Search Results (360)

Jakarta frequently experiences flooding due to several sources. To address this, the Indonesian government initiated the Great Garuda Seawall (GGSW), a structural countermeasure to protect the city from floods. This study assesses the effectiveness of the GGSW using a storm surge model. Four events were simulated to evaluate storm surge variations: without the GGSW, and in three construction phases (initial, intermediate, and completion phases). The results derived from the model depict the maximum storm-surge heights near the Jakarta coastline as 10 cm, 12 cm, 14 cm, and 24 cm for the events of Borneo Vortex, Hagibis–Mitag, Peipah, and Cold Surge, respectively. The effects also extended slightly to the Kepulauan Seribu Regency. Among the construction phases, the intermediate phase was identified as the most critical because the eastern reservoir gate remained open. In the completion phase, attention is needed for the gate connection between reclaimed lands and the Jakarta mainland, especially near the Bekasi region, where coastal erosion risk is high. Overall, the GGSW is not yet fully effective in preventing coastal flooding because some areas still experience no reduction in storm surge height. Furthermore, an evaluation based on GGSW construction phases is also important because this project generally involves reclamation islands and water pumps, which must be carefully cross-engineered. Full article

Urban morphology, climate, and occupant behavior significantly affect urban building energy consumption. This study analyzed 200 example blocks with 4754 buildings in Harbin, China, a representative city with a severe cold climate, to calculate urban morphology and climate factors. A questionnaire was conducted to quantify the data on the energy use behaviors of building occupants. Linear and nonlinear methods were used to explore correlations between these three types of factors and energy consumption. An agent-based modeling (ABM) approach was applied to establish a city-scale energy consumption simulation model, and simulations of energy-saving scenarios were carried out to derive optimization strategies. Key findings include: (1) the living area is the most significant determinant of daily energy use intensity (EUI), contributing 24.42%; (2) the floor area ratio (FAR) most influences annual electricity EUI (30.55%), while building height (BH) has the largest impact on heating EUI (32.62%); and (3) altering urban morphology and climatic factors by one unit can, respectively, reduce energy consumption by up to 13.0 and 224.7 kWh/m² annually. Increasing energy-saving awareness campaigns can reduce household EUI by 30.6127 kWh/m². This study provides strategic recommendations for urban energy-saving planning in cold regions. Full article

Severe floods such as in the Ahr valley in July 2021 are one of the leading causes of fatalities from natural disaster. Riverine and lacustrine floods are caused by a sudden flux of water masses from heavy rainfall or snowmelts. These surface water runoff events significantly enhance erosion of detrital material in the catchment, which is then deposited in natural sinks such as lakes. We reconstructed flood phases from Eifel maar lakes over the last 60,000 years and compared flood behavior with regional riverine flood data covering the past 1000 years. Multi-centennial flood cycles persisted throughout the Holocene with durations of flood-poor periods significantly decreasing around 3700 years ago due to human activity in the Eifel region. Holocene flood frequency peaked in the 13th and 14th centuries during the medieval agricultural revolution. Late Pleistocene flood phases occurred during the Younger Dryas and Heinrich stadials and represent surface runoff events in cold and dry climates. As flood behavior is strongly affected not only by increased water supply but also by soil stability and erosion processes in the catchment area, flood phases reflect shifts in the prevailing climate conditions and vegetation cover, either through natural steppe formation or human impact. Full article

This study presents the experimental and thermodynamic evaluation of a solar thermochemical refrigeration system (STRS) powered by evacuated tube solar collectors with heat pipes as thermal energy sources, using industrial-grade BaCl₂–NH₃. The system was designed to produce refrigeration and ice using industrial-grade BaCl₂–NH₃ without additional additives or electrical input. Experimental tests were conducted under real-world conditions, with generation temperatures between 55 and 66 °C and solar irradiance of 750 to 900 W/m². The system achieved efficient ammonia desorption, yielding up to 4.2 L of refrigerant and demonstrating repeatable operation over several thermochemical cycles. During the nighttime absorption–evaporation process, the STRS reached evaporation temperatures of −7 to −3 °C and absorption temperatures between 24 and 31 °C, suitable for ice production. The internal coefficient of performance ranged from 0.244 to 0.307, with an overall efficiency of 0.146 to 0.206. The experimental data obtained were used to derive pressure–temperature equilibrium equations for the BaCl₂–NH₃ working pair, yielding correlation coefficients greater than 0.98, which confirms thermodynamic consistency. The results demonstrate that additive-free, industrial-grade BaCl₂ can achieve high efficiency at low temperatures, making this system a cost-effective and sustainable alternative for refrigeration and cold storage in rural areas. This research contributes new experimental knowledge on low-temperature thermochemical refrigeration and supports future development toward quasi-continuous optimization cycles based on experimental data. Full article

Coal gangue concrete in high, cold mines in western China is subject to freeze–thaw damage due to prolonged low temperatures and large temperature variations, leading to surface spalling, cracking, and degradation of mechanical performance. In this study, four coal gangue concrete mixtures with replacement ratios of 0%, 20%, 40%, and 60% were prepared using gangue from the Halagou Mine in the Shendong area. Freeze–thaw cycle tests were conducted to analyze the effects of the replacement rate and number of cycles on compressive strength, elastic modulus, and peak strain. The results show that both compressive strength and elastic modulus decrease with increasing freeze–thaw cycles, while the peak strain increases. After 80 cycles, the compressive strength of the M0, M20, and M40 groups decreased by 35.0%, 41.8%, and 51.1%, respectively, and their elastic modulus dropped by 49.2%, 86.2%, and 92.0%. The M60 group was too severely damaged to be tested. Based on the experimental data, a constitutive model for coal gangue concrete under freeze–thaw conditions was developed and validated using Abaqus finite element analysis, with simulation errors below 10%. Considering both mechanical performance and resource utilization, the optimal coal gangue replacement rate is determined to be 20%. Full article

Background/Objectives: Surgical debridement and early excision of burned areas followed by skin autograft is the gold standard of treatment for partial and full-thickness pediatric burns. However, skin autografting might be unfeasible or unlikely to succeed due limited availability of skin donor areas or inadequate conditions. In these circumstances, alternative treatment is required, and Skin Substitutes (SS) cold play a role. Recently, Biological Skin Substitutes (BSS) and Tissue Engineered Skin Substitutes (TESS) are emerging as alternative treatment options, but strong evidence is missing. This review investigates the current literature focusing on BSS and TESS, aiming to improve the medical and surgical management of pediatric patients. Methods: A systematic review was performed in accordance with the PRISMA 2020 guidelines and registered in the PROSPERO database (CRD42024627569). A comprehensive search was conducted in PubMed (MEDLINE) from 2000 to 2024 using Boolean logic and PICO-based inclusion criteria. Study quality was assessed using the Joanna Briggs Institute (JBI) critical appraisal checklists according to study design. Results: Twenty-nine articles and 2676 pediatric patients undergoing surgical reconstruction by BSS or TESS for burns were included. The methodological quality was generally moderate, with most studies being observational or case series. Several strategies were critically analyzed and possibly discussed. Conclusions: While BSS and TESS are safe and effective reconstructive options, the overall level of evidence remains low to moderate. A schematic classification of SS for pediatric burns is presented. Further prospective trials are needed to define standardized algorithms for pediatric burn reconstruction. Full article

Integrated urban–rural development is of great significance in promoting coordinated development in underdeveloped areas across provinces and advancing common prosperity. Previous studies have mostly focused on typical counties in single or developed areas, with insufficient exploration of integrated urban–rural development in underdeveloped areas. A total of 71 counties in Wuling Mountain area were taken as the research object, and a conceptual model of “element–structure–function” was constructed based on the theory of the urban–rural integration system. The entropy weight ideal point method, variation coefficient method, coupling coordination model, and obstacle model were employed to analyze the integrated urban–rural development in counties of the Wuling Mountain area during 2010 and 2023 from the five dimensions of population, economy, space, society, and ecology, and to explore their coupling coordination relationship and key obstacle factors. The research results indicate the following: (1) During the study period, the average annual growth rate of integrated urban–rural development was only 1.213%, showing a relatively low level. The spatial evolution exhibited a trend of “overall optimization–gap convergence–multipolar linkage–hot in the south and cold in the north”. (2) The comprehensive coupling coordination increased from 0.6380 in 2010 to 0.7016 in 2023, and the coupling coordination of “population–space” became the dominant mode. Nearly 60% of counties achieved a level upgrade from the transition stage to the coordination stage, and the multidimensional coordination relationship was mainly affected by the dual effects of spatial polarization and ecological constraints. (3) The obstacle of spatial integration ranked first and the mismatch of factors was severe. Land urbanization and population distribution imbalance were key obstacles, and their core contradictions were concentrated in the tripartite dilemma of “extensive land utilization–factor blockage–ecological antagonism”. It is urgent to achieve coordinated and sustainable development of urban and rural integration through market-oriented reforms of two-way factor flow. The conceptual model of “element–structure–function” constructed by the research results can provide a theoretical tool for analyzing the integrated development of urban and rural areas in counties, and can provide decision support for solving the dilemma of element mismatch. Full article

This study aimed to identify electrophysiological markers (event-related potentials, ERPs) of intentional, need-related mental activity under controlled gaze fixation, with potential applications in brain–computer interface (BCI) development for individuals with severe motor impairments. Methods: Using stimuli from the PAIN Pictionary—a pictogram database for non-verbal communication in locked-in syndrome (LIS) contexts—neural responses were recorded via high-density EEG in 30 neurologically healthy adults (25 included after artifact-based exclusion). Participants viewed randomized sequences of pictograms representing ten fundamental need categories (e.g., “I am cold”, “I’m in pain”), with one category designated as the target per sequence. Each pictogram was followed by a visual cue prompting a button press: during training, participants executed the press; during the main task, they performed right-hand motor imagery while maintaining central fixation. Results: ERP analyses revealed a robust P300 response (450–650 ms; p < 0.0002) over centro-parietal regions for target cues, reflecting enhanced attentional allocation and stimulus choice. An early Contingent Negative Variation (CNV, 450–750 ms; p = 0.008) over fronto-lateral sites indicated anticipatory attention and motor preparation, while a left-lateralized late CNV (2250–2750 ms; p = 0.035) appeared to embody the preparation of a finalized motor plan for the forthcoming right-hand imagined response. A centro-parietal P600 component (600–800 ms; p = 0.044) emerged during response monitoring, reflecting evaluative and decisional processes. SwLORETA source analyses localized activity within a distributed network spanning prefrontal, premotor, motor, parietal, and limbic areas. Conclusions: These findings demonstrate that motor imagery alone can modulate pattern-onset ERP components without overt movement or gaze shifts, supporting the translational potential of decoding need-related intentions for thought-driven communication systems in individuals with profound motor impairments. Full article

The operation of modern power networks is increasingly exposed to overlapping climate extremes and volatile system conditions, making it essential to adopt scheduling approaches that are resilient as well as economical. In this study, a two-stage stochastic formulation is advanced, where indicators of system adaptability are embedded directly into the optimization process. The objective integrates standard operating expenses—generation, reserve allocation, imports, responsive demand, and fuel resources—with a Conditional Value-at-Risk component that reflects exposure to rare but damaging contingencies, such as extreme heat, severe cold, drought-related hydro scarcity, solar output suppression from wildfire smoke, and supply chain interruptions. Key adaptability dimensions, including storage cycling depth, activation speed of demand response, and resource ramping behavior, are modeled through nonlinear operational constraints. A stylized test system of 30 interconnected areas with a 46 GW demand peak is employed, with more than 2000 climate-informed scenarios compressed to 240 using distribution-preserving reduction techniques. The results indicate that incorporating risk-sensitive policies reduces expected unserved demand by more than 80% during compound disruptions, while the increase in cost remains within 12–15% of baseline planning. Pronounced spatiotemporal differences emerge: evening reserve margins fall below 6% without adaptability provisions, yet risk-adjusted scheduling sustains 10–12% margins. Transmission utilization curves further show that CVaR-based dispatch prevents extreme flows, though modest renewable curtailment arises in outer zones. Moreover, adaptability provisions promote shallower storage cycles, maintain an emergency reserve of 2–3 GWh, and accelerate the mobilization of demand-side response by over 25 min in high-stress cases. These findings confirm that combining stochastic uncertainty modeling with explicit adaptability metrics yields measurable gains in reliability, providing a structured direction for resilient system design under escalating multi-hazard risks. Full article

The roles of man-made weirs in flood control during the summer monsoon are well-known, but the function of habitats for wintering water birds has not been explored. This study examined the effects of man-made weirs on the wintering distribution of water birds in Tancheon Stream, Korea, with a focus on the impact of the freeze–thaw process. Data collected from January to February 2003 included thawed water surface ratios, water depths, sandbar areas, and bird distribution under different weather conditions. The analysis revealed a strong positive correlation between thawed surface areas in front of the weir’s drop structures and the abundance of dabbling and diving water birds during severe cold conditions with temperatures below −9 °C. However, it was also observed that the stagnant water impounded by the weirs tended to freeze easily in winter, making it difficult for water birds to inhabit those areas. These results suggest an adaptation of wintering water birds to man-made weirs in urban streams, providing significant insights for enhancing habitat functions in urban stream management. Full article

Background/Objectives: Rapid, objective phenotyping of donor kidneys is needed to support peri-implant decisions. Label-free Fourier-transform infrared (FTIR) spectroscopy of static cold-storage Celsior^® perfusion fluid can discriminate kidneys recovered from donation after circulatory death (DCD) versus donation after brain death (DBD). Methods: Preservation solution from isolated kidney allografts (n = 10; 5 DCD/5 DBD) matched on demographics was analyzed in the Amide I and fingerprint regions. Several spectral preprocessing steps were applied, and feature extraction was based on the Fast Correlation-Based Filter. Support vector machines and Naïve Bayes were evaluated. Unsupervised structure was assessed based on cosine distance, multidimensional scaling, and hierarchical clustering. Two-dimensional correlation spectroscopy (2D-COS) was used to examine band co-variation. Results: Donor cohorts were well balanced, except for higher terminal serum creatinine in DCD. Quality metrics were comparable, indicating no systematic technical bias. In Amide I, derivatives improved classification, but performance remained modest (e.g., second derivative with feature selection yielded an area under the curve (AUC) of 0.88 and an accuracy of 0.90 for support vector machines; Naïve Bayes reached an AUC of 0.92 with an accuracy of 0.70). The fingerprint window was most informative. Naïve Bayes with second derivative plus feature selection identified bands at ~1202, ~1203, ~1342, and ~1413 cm⁻¹ and achieved an AUC of 1.00 and an accuracy of 1.00. Unsupervised analyses showed coherent grouping in the fingerprint region, and 2D correlation maps indicated coordinated multi-band changes. Conclusions: Performance in this 10-sample pilot should be interpreted cautiously, as perfect leave-one-out cross-validation (LOOCV) estimates are vulnerable to overfitting. The findings are preliminary and hypothesis-generating, and they require confirmation in larger, multicenter cohorts with a pre-registered analysis pipeline and external validation. Full article

Centralized heating systems in severe cold regions suffer from widespread load estimation deviations due to architectural heterogeneity and a lack of construction drawings, leading to substantial energy waste. This study proposes a lightweight load calculation method that facilitates efficient calculation of heating loads for heterogeneous building clusters via spatial thermal pattern decoupling and matrix reorganization. First, a 3 × 3 load characteristic matrix is developed to characterize the spatial variation in thermal demand across different building positions (corner vs. intermediate units × top, middle, and bottom floors), revealing that corner units exhibit higher thermal loads than intermediate units, while top and bottom floors show significantly higher loads than middle floors. Second, two complementary matrices are established: the load characteristic matrix, which represents the building’s thermal behavior, and the structural feature matrix, which encodes the architectural configuration in terms of unit count (a) and floor count (b). Together, they enable rapid hourly load synthesis using only lightweight input parameters. The method is validated on 56 heterogeneous residential buildings in Northeast China. Using a decoupled 4U/6F standard model, the synthesized cluster heating load achieves an R² of 0.88, an RMSE of 24.15 GJ, a MAPE of 4.94%, and a Mean Percentage Error (MPE) of −0.82% against actual heating supply data, demonstrating high accuracy and negligible systematic bias—particularly during cold waves. This approach allows the seasonal variation in heat demand across an entire residential area to be estimated even in the absence of detailed construction drawings, offering practical guidance for operational heating management. Full article

Against the backdrop of the global energy crisis and the “dual carbon” goals (carbon peaking and carbon neutrality), the passive energy-saving design of substation buildings in cold regions faces severe challenges. This study systematically conducts a decomposed analysis of the shape coefficient, thermal performance of the building envelope (including external walls, internal walls, roofs, and external windows), and window-to-wall ratio of substation buildings in cold regions, quantifies the degree of influence of each factor, and proposes corresponding energy-saving design strategies. This study took a 110 kV substation in Yuhua District, Shijiazhuang City, Hebei Province, as the research object. A building energy consumption model was established based on DeST (2023) software, and the influence of the building shape coefficient, U-values of the envelope structure (external walls, internal walls, roofs, external windows), and window-to-wall ratio on the building’s cooling and heating loads was analyzed using the numerical simulation and control variable methods. Leveraging a rigorously validated, high-resolution simulation framework, we quantitatively dissect the marginal energy penalties and payoffs of every passive design variable governing fully indoor substations in cold-climate zones. The resultant multidimensional response surfaces are distilled into a deterministic, climate-specific passive energy-saving protocol that secures heating-energy savings of up to 43% without compromising electrical safety or operational accessibility. (1) Reducing the shape coefficient can significantly lower the heat load, and it is recommended to control it at 0.35–0.40; (2) The thermal performance of the envelope structure has a differential effect: the energy-saving effect is optimal when the U-value of external walls is 0.20–0.30 W/(m²·K) and the U-value of roofs is ≤0.25 W/(m²·K). A U-value of 2.4 W/(m²·K) is recommended for external windows, while the internal wall exerts a weak influence; (3) The window-to-wall ratio should be controlled by orientation: east-facing/north-facing ≤ 0.20, south-facing ≤ 0.35, and west-facing ≤ 0.30. Based on the above results, a comprehensive energy-saving strategy of “compact form–high-efficiency envelope–limited window-to-wall ratio” is proposed, which provides theoretical support and technical pathways for the energy-saving design of substation buildings in cold areas. Compared with existing substation buildings, the recommended parameters yield a significant reduction in total life-cycle carbon emissions and hold important practical significance for realizing the “dual carbon” goals (carbon peaking and carbon neutrality) of the power system. Full article

Potato is an important crop in the world and is rich in various nutrients. Common tetraploid potato is not tolerant of low temperatures and frost. Low-temperature stress severely affects the growth above-ground and the yield underground in potato. The BBX genes play an important role in the plant response to low-temperature stress. However, the molecular mechanism underlying the potato StBBX genes involved in cold stress response remains unclear. In the present study, 30 StBBX genes were identified in potato and divided into five groups. A total of 10 motifs and 10 cis-acting elements were obtained in all BBX proteins. All StBBX genes contained light responsive elements in the promoter, of which nine StBBX genes harbored low-temperature responsive elements. In total, 15 pairs of StBBX genes were identified in duplicated genomic regions. The gene expression patterns of all StBBXs were assessed in different tissues by transcriptome data. The qRT-PCR analysis indicated that six StBBX genes were significantly induced in response to cold stress. Subcellular localization suggested that the StBBX17 protein was localized in the nucleus. Compared with wild type (WT), the cold tolerance in StBBX17 overexpression lines was dramatically increased. After cold treatment, the StBBX17 overexpression lines displayed a less injured area of leaves and lower electrolyte leakage compared with the WT plants, demonstrating StBBX17 positively regulated cold tolerances in potato. These results indicate that StBBX genes have important functions under cold stress, providing a theoretical reference for the breeding of cold-resistant potato. Full article

In global cold regions and seasonal frozen soil areas, frost heave failure of rock slopes severely endangers infrastructure safety, particularly along China’s Sichuan–Tibet and Qinghai–Tibet Railways. To address this, a meshless numerical model based on the smoothed particle hydrodynamics (SPH) method was developed to simulate progressive frost heave and fracture of water-saturated fissured rock masses—its novelty lies in avoiding grid distortion and artificial crack path assumptions of FEM as well as complex parameter calibration of DEM by integrating the maximum tensile stress criterion (with a binary fracture marker for particle failure), thermodynamic phase change theory (classifying fissure water into water, ice-water mixed, and ice particles), and the equivalent thermal expansion coefficient method to quantify frost heave force. Systematic simulations of fissure parameters (inclination angle, length, number, and row number) revealed that these factors significantly shape failure modes: longer fissures and more rows shift failure from strip-like to tree-like/network-like, more fissures accelerate crack coalescence, and larger inclination angles converge stress to fissure tips. This study clarifies key mechanisms and provides a theoretical/numerical reference for cold region rock slope stability control. Full article