Previous studies of freshwater lenses in saline aquifers adjoining gaining rivers ("riparian lenses") have so far considered only rivers that fully penetrate the aquifer, whereas in most cases, rivers are only partially penetrating. This paper presents a new methodology for obtaining the saltwater discharge and the shape of a steady-state, non-dispersive riparian lens, where the river is partially penetrating, combining two previous analytical solutions. The resulting analytical solution is compared to numerical modeling results to assess assumptions and the methodology adopted to approximate the "turning effect," which is the change in groundwater flow direction (horizontal to vertical) near the partially penetrating river. Model parameters were taken from previous studies, representing simplified conditions in the River Murray floodplains (Australia). Consistency between analytical and numerical results and field observations highlights the capability of the proposed analytical solution to predict the riparian lens geometry and saltwater discharge into partially penetrating rivers. Sensitivity analysis indicates that larger riparian lenses are produced adjacent to the deeper and wider rivers, as expected. The change in width or depth of the river has more influence on the saltwater discharge and the horizontal extent of the riparian lens (and less effect on the vertical extent of the lens adjacent to the river) for shallower and narrower rivers. This research highlights the utility of the new method and demonstrates that the assumption of a fully penetrating river likely leads to significant overestimation of the saltwater discharge to the river and the riparian lens horizontal extent and vertical depth.

Freshwater lenses within riparian zones of some arid and semiarid settings assist in maintaining the health of riparian ecosystems. We propose an approach for expanding freshwater lenses in saline aquifers adjacent to gaining rivers through the addition of a vertical barrier of low‐hydraulic‐conductivity (low‐K) parallel to the river bank. Sharp‐interface analytical solutions for the lens shape and water table distribution are developed to examine the effectiveness of the proposed method and are verified using sand tank experiments and numerical simulations. The sensitivity analysis is used to apply the method to parameters typical of the Lower River Murray (South Australia) and its floodplain aquifers. The results show that the barrier can create significant freshwater lenses in head‐controlled systems, whereas the barrier may lead to lens shrinkage in flux‐controlled systems due to saline water table rise. That is, the effectiveness of the barrier is highly dependent on the inland boundary condition. The analytical solution presented herein can be used to efficiently predict the riparian freshwater lens extent in response to engineered barriers, adding to existing techniques for studying and modifying riparian freshwater lenses.

Freshwater lenses have been observed within riparian aquifers where freshwater rivers traverse and connect to saline groundwater (e.g., Cendón et al., 2010;Laattoe et al., 2017). Such settings are encountered in arid and semi-arid regions where saline groundwater often occurs because of significant evapo-concentration effects (Alaghmand et al., 2013;Bauer et al., 2006). The fresh groundwater found in riparian zones (i.e., buoyant, lenticular-shaped freshwater bodies adjacent to rivers; "riparian lenses" hereafter) play an important role in sustaining fragile riparian and floodplain ecosystems (e.g., the Chowilla floodplain, South Australia; Holland et al., 2009) in arid and semi-arid regions, particularly during low-flow periods (e.g., Holland

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Subsurface physical barriers have been recognized as effective in mitigating seawater intrusion in coastal aquifers, although mainly 2D (cross-sectional) barrier effects have been considered. In this study, impermeable barriers with finite shore-parallel lengths are investigated through 3D numerical simulation, thereby extending previous analyses. Two scenarios are considered: (a) barrier-only and (b) barrier-well systems; and three available barrier types are analyzed and compared: (1) subsurface dam, (2) cutoff wall, and (3) fully penetrating barrier. Barrier location, length, and height are investigated, and barrier effectiveness is evaluated from seawater volumes, seawater wedge toe positions, and maximum safe pumping rates. In the barrier-only system, a better performance in preventing seawater intrusion was achieved by cutoff walls rather than subsurface dams. Finite-length subsurface dams may slightly enhance seawater extent along parts of the coastline that are beyond the dam's length. Cutoff walls performed best when located at relatively small distances from the coast in the barrier-only system, whereas with a well at 450 m from the shoreline, the subsurface dam located at a critical distance from the sea (i.e., 300 m in the current study) performed optimally (from the tested cases) and was superior to cutoff walls in terms of the maximum safe pumping rate. A fully penetrating barrier outperformed cutoff walls and subsurface dams, as expected. Our investigation indicates that subsurface barrier design should consider the effect of the shore-parallel length, because barrier benefits may otherwise be significantly overestimated.

In this paper, we used the "Moral Judgment Test" (MJT), an instrument that was developed by German psychologist, Georg Lind in 1976, along with some additional items, administered after the standard MJT. The participants were 724 Chinese adolescents whose ages ranged from 14 to 27 years of age. The results show that there was considerable fluctuation between grades in C scores, without the regularity seen in prior studies conducted in Western cultural contexts, but with senior college students generally showing higher C scores than freshmen. No significant differences in C scores were found between male and female students, between students with various professions, between key schools and the regular schools and between the two-year and the four-year college students. The possible implications of these findings for Chinese moral education are also discussed.

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We constructed a water-soluble lipopolymer (WSLP) as a nonviral gene carrier to deliver siRNA targeting NR2B. The cytotoxicity and serum stability of WSLP loaded with siRNA were evaluated, and the knockdown efficiency of WSLP/NR2B-siRNA in PC12 cells was examined. The results showed that WSLP could protect the loading siRNAs from enzymatic degradation in serum and exhibit low cytotoxicity to cells. After transfection, WSLP/NR2B-siRNA complexes reduced the NR2B transcriptional level by 50% and protein level by 55% compared to control siRNA. Moreover, 3 days after intrathecal injection of WSLP/NR2B-siRNA complexes into rats, the NR2B protein expression decreased significantly to 58%, compared to control treatment (p < 0.01). Injection of WSLP with scrambled siRNA or of polyethylenimine (PEI) with NR2B-siRNA did not show this inhibitory effect. Additionally, injection of WSLP/NR2B-siRNA complexes significantly relieved inflammatory pain in rats at 3, 4, and 5 days with reduced MWT and decreased TWL scores, while injection of WSLP with scrambled siRNA or of PEI with NR2B-siRNA did not. These results demonstrated that WSLP can efficiently deliver siRNA targeting NR2B to PC12 cells and relieve pain in rats with chronic inflammatory pain.