Atmospheric aerosols are known to alter the Earth's radiative balance and influence climate. However, accurately quantifying the magnitude of aerosol-induced radiative forcing remains challenging. We characterize optical properties of biomass-burning (BB) and non-biomass-burning (NB) aerosols and quantify BB aerosol radiative forcing at two AERONET (AErosol RObotic NETwork) sites in Huancayo (Peru) and La Paz (Bolivia) during 2015-2021. From AERONET data, we derive aerosol optical depth (AOD), & Aring;ngstr & ouml;m exponent (AE), single-scattering albedo (SSA), and asymmetry parameter (ASY). We then employ the SBDART model to calculate aerosol radiative forcing (ARF) on monthly and multiannual timescales. BB aerosols peak in September (AOD: 0.230 at Huancayo; 0.235 at La Paz), while NB aerosols reach maxima in September at Huancayo (0.109) and November at La Paz (0.104). AE values exceeding unity for BB aerosols indicate fine-mode dominance. Huancayo exhibited the highest BB ARF in November: +16.4 W m-2 at the top of the atmosphere (TOA), -18.6 W m-2 at the surface (BOA), and +35.1 W m-2 within the atmospheric column (ATM). This was driven by elevated AOD and high scattering efficiency. At La Paz, where SSA data was only available for September, BBARF values were also significant (+15.16 at TOA, -17.52 at BOA, and +32.73 W m-2 within the ATM). This result underscores the importance of quantifying the ARF, particularly over South America where data is scarce.

Laboratory experiments have shown that the proportional shearing of granular materials along arbitrary strain path directions will lead to stress states that converge asymptotically to proportional stress paths with constant stress ratios. The macro- and microscopic characteristics of this asymptotic behaviour, as well as the existence of asymptotic states exhibiting a constant stress ratio and a steady strain-rate direction, have been studied using the discrete element method (DEM). Proportional shearing along a wide range of strain-rate directions and from various initial stress/density states has been conducted. The simulation results suggest that general contractive asymptotic states (except for isotropic states) do exist but may be practically unattainable. Dilative strain path simulations, on the other hand, result in continuously changing stress ratios until static liquefaction occurs, indicating the absence of dilative asymptotic states. Despite this difference, a unique relationship between the stress increments and the current stress ratio gradually emerges from all strain path simulations, regardless of strain path direction and initial stress/density conditions. At the particle scale, the granular assembly sheared along proportional strain paths exhibits a constant partition ratio between strong and weak contacts. Although general proportional strain paths are associated with changing geometric and mechanical anisotropies, the rates of change in these anisotropies for contractive strain paths are synchronised to maintain a constant ratio of their contributions to the mobilised shear strength of the material, with a higher proportion being contributed by geometric anisotropy for more dilative strain paths.

Underground tunnels subjected to asymmetric load or ground conditions are susceptible to experiencing uneven longitudinal bending, shearing, and torsional deformations, which further induce cross sectional flattening and warping. The intrinsic damages caused by multiple deformation modes are critical for tunnel health and safety but have long been neglected in practice. In the paper, a three-dimensional analytical model for soil-tunnel interactions was proposed with multiple-mode deformations incorporated, where the tunnel is assumed as a thin-walled pipe resting on an elastic foundation with five deformation modes: bending, shearing, torsion, warping, and flattening. Besides, a three-dimensional variable soil spring model was adopted, accounting for the strata discontinuities in longitudinal and transverse directions. A finite element solution for the proposed model was derived under arbitrary external loads using the principle of minimum potential energy. The validity of the proposed model was substantiated through three case studies. Based on the model, the coupling relationship of tunnel structure in transverse and longitudinal directions was revealed. Furthermore, parametric analysis was conducted to reveal the impact of tunnel width-to-thickness ratio, soil resistance coefficient, and composite strata on tunnel behaviors. These results significantly contribute to a deeper understanding of the intricate behaviors of tunnels, offering potential advancements for improved tunnel design methodologies.

With increasing urbanization, many of the current structures in the underground severely limited the space below ground. Shield tunnels need to be built in curved lines to bypass already established tunnels, pilings, and other buildings. Considering that a curve tunnel is overexcavated on the inner side (overexcavated side) during the excavation process and the difference in the jacking forces on the inside and outside of the tunnel, the study of the curved tunnel working face stability is more complicated. In this paper, a curved tunnel excavation model is designed independently, and the visualized transparent soil model test of the curved tunnel is carried out by combining with particle image velocimetry software to investigate the soil progressive damage process during curved tunnel excavation. On basis of designed modeling tests, a three-dimensional asymmetric spatial pattern of the soil arch was further given by using the numerical simulation method, and a detailed analysis of the internal friction angle and the curvature radius on the arch effect of sandy soil was performed. It is indicated that the soil ahead of the curved tunnel shows the shape of a crescent in the cross section, which is offset toward the inner side, and a bubble shape in the longitudinal section. In addition, the maximum value of the settlement tank during tunneling is located on the inner side of the curved tunnel, and there is an asymmetric distribution of the settlement curve along the central axis. The soil ahead of the curved tunnel's working face will have an increased offset to the inside.

Pile foundations supporting wind turbines and offshore platforms are always subjected to asymmetric lateral cyclic loads from wind and waves. To calculate the lateral response of the pile in sand under asymmetric cyclic loading, this paper proposes a p- y curve model to deal with different levels of load reversal. According to the state of the soil around the pile under asymmetric cyclic loading, the scaling factor of the reloading curve is modified. The soil collapse-recompression model is also extended to apply to different cases of asymmetric cyclic loading according to the characteristics of soil convection during asymmetric cyclic loading. By modifying the shape and position of the p- y curves to different degrees, the lateral response of the pile under asymmetric cyclic loading can be obtained in combination with the improved finite difference method. The validity of the proposed model is demonstrated by comparing the results with the centrifuge model tests. Then, the pile displacement accumulation, the variation of the bending moment, and the soil resistance under asymmetric cyclic loading, are further discussed.

The spatial distributions of hydraulic conductivity and shear strength parameters are influenced by the soil structure, property and mineral composition. However, hydraulic conductivity is not only determined by the intrinsic soil property but also influenced by external factors such as fractures and interlayers. This study investigates the impact of the asynchronism between the spatial distribution of hydraulic conductivity and shear strength parameters on the reliability assessment and failure mechanism of unsaturated soil slopes with different titled stratifications under rainfall conditions. The results indicate that the asynchronism in the rotational angles (alpha) of hydraulic conductivity and shear strength parameters shows the greatest impact on the probability of failure (Pf) of slopes. By contrast, the asynchronism in the scales of fluctuation of hydraulic conductivity and shear strength parameters and employing different autocorrelation functions (ACFs) show minor impact on the Pf. The impact of using different ACFs, alpha, and scales of fluctuation to characterise the spatial variability of hydraulic conductivity on sliding mass and failure modes is minimal.

This paper presents a novel strut-free earth retaining wall system for excavation, referred to as the asymmetric double-row pile wall (ARPW) retaining system. This system comprises three key elements: front-row reinforced concrete piles, back-row walls, and connecting crossbeams at the top of the piles. This paper aims to analyze the deformation characteristics and mechanical behavior of the ARPW retaining system, double-row pile wall (DRPW) retaining system, and single-row pile wall (SPW) retaining system using both physical model tests and numerical simulations. The study reveals that, with reasonable row spacing, double-row structures exhibit substantially lower earth pressure and bending moments compared to SPW. Additionally, all double-row structures display reverse bending points. The optimal row spacing for DRPW and ARPW is within the ranges of 2D to 6D and 4D to 8D, respectively. ARPW outperforms DRPW by efficiently utilizing active zone friction force and soil weight force (Gs) to resist overturning moments, thereby resulting in improved anti-overturning capabilities, reduced deformations, lower internal forces, and enhanced stability. The study also presents a case study from the Jinzhonghe Avenue South Side Plot in Tianjin, demonstrating the practical application and effectiveness of the ARPW system in meeting stringent deformation requirements for deep foundation pits. These research findings provide valuable insights for practical engineering applications.

The application of rhizobia-legume symbioses is a sustainable approach to alleviate water stress and restore damaged areas. In this context, three strains Bradyrhizobium sp. BA2, RDI18 and RDT46 previously isolated from root nodules of Retama dasycarpa grown in the Moroccan High Atlas Mountains, were selected to investigate their prominent drought-tolerance capacity and significant plant growth-promoting (PGP) traits under drought stress. Subsequently, we analyzed the impact of individual or combined inoculations by the three strains on R. dasycarpa responses to three water regimes (40, 70, and 100 field capacity). The three strains tolerate different concentrations of PEG 6000 and possess different PGP activities, including phosphate solubilization, production of siderophore, exopolysaccharides, and auxin, under osmotic stress. The inoculation had a positive impact on plant response under all applied water regimes as it improved shoot and root length biomass, and chlorophyll content. The water stress reduced shoot length and dry weight of all plants. However, the inoculated plants maintained the highest values. The water stress reduced the infectivity of strains BA2 and RDI18, but not strain RDT46, which is not competitive at any water regime. Furthermore, water stress had no effect on the three strains' symbiotic efficiency, whereas it increased considerably the efficiency index of strains BA2 and RDI18. Proline and protein content increased in non-inoculated plants; whereas the inoculation significantly increased the catalase activity in plants under 40 % FC. These results show that the inoculation with appropriate strains such as BA2 and RDI18, enhance plant resilience to drought season.

This paper investigates the effects on the behavior of a saturated porous material of an evolving microstructure induced by the mass exchange between the solid and the fluid phases saturating the porous network, using two-scale asymptotic expansions. A thermodynamically consistent model of the fluid physics flowing through the porous network is proposed first, describing microstructure variations to be captured implicitly via the level set method. The two-scale asymptotic expansions method is then applied to obtain an upscaled model capable to account for mass transfer. This last is proven to depend not only on the gradient of the macroscopic forces, such as the fluid pressure and the chemical potential, but also on the average velocity of the solid-fluid interface. Numerical simulations are carried out using the finite element method in order to evaluate the relative weight of the new terms introduced.

The 11 September 2001 terrorist action organized on US soil by the transnational jihadist group al-Qaeda represented a phenomenological novelty with epochal implications: The ability to simultaneously hijack four airliners and crash them, with hundreds of passengers forced to die along with the suicide bombers, against the capital symbols of American > (the capitalist economy projected by the Twin Towers, the military organisation centred on the Pentagon, the democratic liberalism recognised in the Capitol), causing almost 3,000 casualties, over 6,000 injured, and 25 billion dollars in material damage, effectively revolutionised the offensive and communicative modus operandi of politically motivated violence as it had been expressed in the modern Western sphere. At the same time, this huge and traumatic event decreed a securitarian reaction throughout the Euro-Atlantic system, driven by the winds of the > launched by the G. W. Bush administration. With the unprecedented terrorist rupture of the USA's inviolability and the consequent American attempt to unilaterally reestablish its own planetary hegemony through pre-emptive strikes, the marginalisation of international humanitarian law and the forced export of the Western model of democracy, a new historical era was thus inaugurated, coinciding with the beginning of the third millennium, under the sign of existential fear.