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Quantifying how tides evolve with coupling between future sea level rise (SLR) and different coastline configurations is imperative for proposing appropriate coastal defense strategies. By using numerical models, we investigated tidal changes and determined a realistic trend of SLR on the Jiangsu coastal area and adjacent sea on the Yellow Sea shelf. A notable decrease in tidal range occurs in the northern shelf, and the tide increases mainly in the southern shelf. Tidal changes are of both signs, while the increase in sea level is unidirectional. Thus, the SLR effect on tide is not additive in all locations. We also explored the nonlinearity and spatial similarity in tidal range in response to the SLR considering uniform SLR scenarios with multiple levels and allowing inundation of the natural coastline. The patterns of change in tide evolution on the study domain remain linear until the SLR exceeds 2.0 m. Simulations and comparisons are further conducted between the responses of hardened and natural shoreline configurations to SLR. Hardened shoreline introduces both local and remote spatial variability in tidal responses. On the regional scale, SLR induces a shift in the tidal system in the offshore region, which controls the net energy flux into the embayment upon the coast. On the local scale, tidal dynamics are mainly a competition between net energy flux and tidal dissipation and are plausibly influenced by tidal reflection, which depends on whether a basin is tidally reflective. China has experienced rapid economic growth and irreversible pressures from sea level rise (SLR) in the eastern coastal region. To provide future coastal defense strategies, we conduct multiple experiments to simulate how tides evolve with future SLR scenarios as well as how tides respond to different coastline configurations. We found that the future SLR can adjust the entire tidal system and control how much tidal energy flows into the local area from the deep ocean. Whether to build up or maintain a seawall for coastal defense depends on local conditions. By preserving the natural coast and removing the impermeable seawall from the radial sand ridges of China, tidal waves become more progressive on the shoals. Tidal change remains linear under a 2.0‐m sea level rise within which a large spatial similarity was achieved on the Yellow Sea shelfDisplacement in the amphidromic point on the northern Yellow Sea shelf dominates the tidal range evolution for the Jiangsu coastal areaThe seawall of Jiangsu with SLR enlarges the tidal range where the tide is reflective but functions opposite where the tide is parallel to the coast

Oscillations within a rectangular harbor of parabolic bottom induced by small-scale landslides are investigated numerically based on Boussinesq-type equations and the results are used to reveal the characteristics of the oscillations generated on this type of bottom profile. Relatively, local and small-scale landslides within the harbor may induce obvious transverse oscillations. The predominant transverse components are those with small mode numbers mand nwhen the solid slides start moving from the backwall. The augmentation of the velocity of the slides along the parabolic seafloor may shift the amplitudes of the oscillation components to larger values, which corresponds to the physical understandings of the waves generated by landslides. In comparing the oscillations induced by the slides of constant velocity and those accelerated by gravity force with bottom friction, it is observed that the movements accelerated by gravity force may facilitate the development of certain oscillation modes while those with constant velocity may be in favor of others. While the landslides may not act on an isolated point of the bottom but follow a certain trajectory along the harbor, the transverse oscillations induced by landslides are sensitive to their position of departure both in the cross-harbor direction and in the offshore direction. The numerical result of each transverse eigenfrequency is very close to the theoretical prediction and the spatial structure of each mode may also be well captured by the existing analytical solutions based on shallow water equations. Although longitudinal oscillations may not be steadily generated with landslide movements on a parabolic bottom within the harbor, some patterns of several low-mode ones occur and are also sensitive to the initial location and trajectory of the slides. Wavelet spectra are used to analyze their evolutions and comparisons are made with theoretical predictions.

Evidences have shown that pulsed electromagnetic fields (PEMFs) can partially prevent bone loss in streptozotocin (STZ)-induced diabetic rats. However, the precise mechanisms accounting for these favorable effects are unclear. This study aimed to investigate the effects of PEMFs on bone mass and receptor activator of nuclear factor κB ligand (RANKL)/osteoprotegerin (OPG) and Wnt/β-catenin signaling pathway in STZ rats. Thirty 3-month-old Sprague Dawley rats were randomly divided into the following three groups (n= 10): control group (injection of saline vehicle), DM group (injection of STZ), and PEMFs group (injection of STZ + PEMFs exposure). One week following injection of STZ, rats in the PEMFs group were subject to PEMFs stimulus for 40 min/day, 5 days/week, and lasted for 12 weeks. After 12 week intervention, the results showed that PEMFs increased serum bone-specific alkaline phosphatase level and bone mineral density, and inhibited deterioration of bone microarchitecture and strength in STZ rats. Furthermore, PEMFs up-regulated the mRNA expressions of low-density lipoprotein receptor-related protein 5, β-catenin and runt-related gene 2 (Runx2), and down-regulated dickkopf1 in STZ rats. However, mRNA expressions of RANKL and OPG were not affected by PEMFs. PEMFs can prevent the diabetes-induced bone loss and reverse the deterioration of bone microarchitecture and strength by restoring Runx2 expression through regulation of Wnt/β-catenin signaling, regardless of its no glucose lowering effect.

Objective To characterise the effects of early and late electroacupuncture (EA) treatment on serum 17ß-oestradiol (E2), C-terminal cross-linking telopeptide of type I collagen (CTX-I), bone mineral density (BMD), biomechanical bone strength and mRNA expression of cathepsin K in ovariectomised (OVX) rats.Methods Sixty Sprague-Dawley rats underwent ovariectomy (n=40) or sham surgery (n=20) and were randomly divided into two batches. Batch 1 (n=30) consisted of 10 sham-operated rats (Sham-0 group) and 20 OVX rats: half commenced EA immediately (early EA group, n=10) and half were left untreated (OVX-0 group, n=10). Batch 2 (n=30) consisted of 10 sham-operated rats (Sham-12 group) and 20 OVX rats: half commenced EA treatment 12 weeks after ovariectomy (late EA group, n=10) and half were left untreated (OVX-12 group, n=10). Rats in batches 1 and 2 were killed after 12 and 24 weeks, respectively. Serum E2, CTX-I, BMD, bone strength and cathepsin K expression were determined by ELISA, dual energy X-ray absorptiometry, biomechanical assessment and qRT-PCR, respectively.Results Both early and late EA treatment increased serum E2 levels, reduced serum CTX- I levels and increased BMD and bone strength of the L5 vertebral body in OVX rats. Although early EA treatment similarly increased BMD and bone strength of the femur, late EA treatment did not. However, both early and late EA treatment reduced mRNA expression of cathepsin K in OVX rats.Conclusions Early EA completely prevented and late EA partially prevented bone loss and deterioration of bone strength in OVX rats. The timing of initiation of EA treatment may be an important consideration for optimisation of effects. The influence of EA on bone strength appears to be at least partially mediated through regulation of the expression of cathepsin K.