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Sub-tidal barotropic current variations coupled with residual sea level fluctuation in the Bohai and Yellow Seas during wintertime are addressed in this study. The temporal evolution and spatial distribution of current fluctuation are investigated using moored acoustic Doppler current profiler data in a three-dimensional numerical model. It is found that a southward current followed by a northward current occurred in the northern Yellow Sea during the fluctuation, concurrent with a significant outflow followed by inflow through the Bohai Strait. The process is consistent from surface to bottom and is coupled with remarkable residual sea level fluctuation. This quasi three-day fluctuation with amplitude 0.2-0.3 m/s leads to 1 m/1.2 m drawdown in the northern Yellow and Bohai Seas, respectively, strongly influencing water exchange between those seas. Because this a prominent feature in the seas, it is necessary to evaluate its effect on fluctuation during winter in future studies, in particular, the northward current during the recovery phase of sea level in the Bohai and Yellow Seas regarding seasonal variation. [ABSTRACT FROM AUTHOR]

The all-optical waveguide theory based on photoisomerization nonlinear effects is systematically and deeply studied, and a nonlinear holographic all-optical waveguide scheme is proposed for the first time. It is found that the induction of a light with stronger isomerization activity on the material weakens the self-defocusing effects of the signal light. Especially, polarization states of both inducing light and signal light also unexpectedly affect propagation of signal light. Part of the theoretical results has been qualitatively confirmed by Z-scan experiments. The proposed holographic all-optical waveguide scheme means polarization information is applied in the all-optical waveguide besides intensity information. Compared with the traditional all-optical waveguide, the performance of holographic waveguide will be greatly improved, making the control of light more precise and easier. Such nonlinear waveguide scheme may find its application in the future all-optical net. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article regarding the issue on the need of China for foreign fertilizers in the 2011 issue.

Purpose: This study was aimed to analyze the contrast-enhanced CT features of gastrohepatic ligament (GHL) involvement in gastric carcinoma (GC) and to evaluate the influence of GHL on the spread of GC correlating with the anatomic bases. Methods: CT scans of 41 patients known to have GC and GHL involvement were reviewed retrospectively for the primary tumor and the GHL abnormalities, as well as the role GHL played in the spread of GC. Emphasis was placed on direct invasion, lymph node metastasis, and GHL seeding. The relationship between the accompanying ascites and the different pattern of the GHL involvement were also evaluated statistically. Results: CT features of the GHL abnormalities caused by GC could be summarized as follows: (a) direct invasion (34.1%, 14 of 41), which was visualized as a regional (nine of 14) or diffuse mass (five of 14) in the GHL; (b) GHL seeding (26.8%, 11 of 41), which consists of ''smudged'' appearance (eight of 11), nodular infiltration (two of 11) and 'GHL caking' (one of 11); (c) lymph node metastasis (63.4%, 26 of 41), including enlargement of lymph nodes (22 of 26) and cystic lesion (four of 26). We also found direct extension of GC into the transverse fissure and/or the liver via the GHL in three patients. Ascites, which was found in ten patients, seemed to be associated with the pattern of seeding involvement. Conclusions: GHL can be invaded by GC through several patterns and contrast-enhanced CT scan plays an important role in detecting GHL involvement in GC, which has a variety of CT manifestations. GHL may also serve as a potential conduit for the predictable spread of GC into the neighboring organs such as the liver. [ABSTRACT FROM AUTHOR]

Three winter storms struck the Bohai and Yellow seas in succession during February 16-25, 2017. Periodic fluctuations of sea level, currents, temperature, and salinity were recorded at a moored station deployed in the Bohai Strait. Observations also captured significant synoptic fluctuations of inflow and outflow through the Bohai Strait with maximum magnitude exceeding 50 cm s−1. The sea level dropped by > 1 m and the bottom temperature decreased by 2.5 °C in < 30 h during these winter storms. A regional ocean model was used to investigate the prominent fluctuations of synoptic exchange flow through the Bohai Strait. The model results indicated that the Bohai and Yellow seas in their entirety responded strongly to the storm bursts and subsequent relaxation at the synoptic scale. The periodic winter storm bursts and relaxation excited the cyclonic propagation of coastal-trapped waves around the Bohai and Yellow seas. Strong periodic inflow and outflow during the passage of the three successive storms promoted water exchange between the Bohai Sea and the northern Yellow Sea. Successive winter storms might also affect the mean current structure through the Bohai Strait. The mean currents through the Bohai Strait during the studied storm period were characterized by inflow in both northern and southern parts of the strait and outflow through the middle of the strait. This arrangement is different from the traditional view of inflow via the northern channel and outflow through the southern channel. [ABSTRACT FROM AUTHOR]

Several bottom-mounted Acoustic Doppler Current Profiler (ADCP) moorings were deployed in the northern Yellow Sea (NYS) during the four seasons of 2006–2007 and also the summertime of 2009. A synthesis analysis on the time-continuous records was performed to examine the characteristics and variations of tidal currents and mean flow over the observation period at these stations. Tidal currents accounted for ~75% of the total kinetic energy, with the absolute dominance of M2 constituent. Visible vertical variations of tidal flow were found on all sites, featured by the decrease of amplitude, increase of rotation rate as well as a decreasing trend of the phase for M2 component with depth. A notable exception was in the central NYS, where the maximum tidal currents occurred in the upper or middle layers (~20–40 m) instead of near the surface (<10 m). The observed mean flow was relatively weak, smaller than 15 cm/s. Velocity on the northern end of Yellow Sea Trough (YST) was characterized by low magnitude and an obvious layered structure vertically. In the Bohai Strait (BS) and the northern slope area, the currents weakened and the flow direction presented a major trend to deflect counterclockwise with depth in most observations. Summertime cyclonic circulation around the Yellow Sea Cold Water Mass (YSCWM), its intensification on the frontal zone and the Yellow Sea Warm Current (YSWC) for the winter season were all evident by our direct current measurements. However, the details of water exchange through the BS appeared partly different from the traditionally-accepted pattern. The vertical differences of tidal and mean flow were larger in summer than that in winter, implying the influence of thermal structure to the local currents. Affected by the water stratification, mean flow usually reached its maximum near the thermocline in spring and summer, while showing a nearly uniform vertical distribution during winter. [ABSTRACT FROM AUTHOR]

Using a Finite-Volume Community Ocean Model, we investigated the dynamic mechanism of the South China Sea Warm Current (SCSWC) in the northern South China Sea (NSCS) during winter monsoon relaxation. The model reproduces the mean surface circulation of the NSCS during winter, while model-simulated subtidal currents generally capture its current pattern. The model shows that the current over the continental shelf is generally southwestward, under a strong winter monsoon condition, but a northeastward counter-wind current usually develops between 50-and 100-m isobaths, when the monsoon relaxes. Model experiments, focusing on the wind relaxation process, show that sea level is elevated in the northwestern South China Sea (SCS), related to the persistent northeasterly monsoon. Following wind relaxation, a high sea level band builds up along the mid-shelf, and a northeastward current develops, having an obvious vertical barotropic structure. Momentum balance analysis indicates that an along-shelf pressure gradient provides the initial driving force for the SCSWC during the first few days following wind relaxation. The SCSWC subsequently reaches a steady quasi-geostrophic balance in the cross-shelf direction, mainly linked to sea level adjustment over the shelf. Lagrangian particle tracking experiments show that both the southwestward coastal current and slope current contribute to the northeastward movement of the SCSWC during winter monsoon relaxation. [ABSTRACT FROM AUTHOR]

For understanding more about the water exchange between the Kuroshio and the East China Sea, We studied the variability of the Kuroshio in the East China Sea (ECS) in the period of 1991 to 2008 using a three-dimensional circulation model, and calculated Kuroshio onshore volume transport in the ECS at the minimum of 0.48 Sv (1 Sv ≡ 10 m/s) in summer and the maximum of 1.69 Sv in winter. Based on the data of WOA05 and NCEP, The modeled result indicates that the Kuroshio transport east of Taiwan Island decreased since 2000. Lateral movements tended to be stronger at two ends of the Kuroshio in the ECS than that of the middle segment. In addition, we applied a spectral mixture model (SMM) to determine the exchange zone between the Kuroshio and the shelf water of the ECS. The result reveals a significantly negative correlation (coefficient of −0.78) between the area of exchange zone and the Kuroshio onshore transport at 200 m isobath in the ECS. This conclusion brings a new view for the water exchange between the Kuroshio and the East China Sea. Additional to annual and semi-annual signals, intra-seasonal signal of probably the Pacific origin may trigger the events of Kuroshio intrusion and exchange in the ECS. [ABSTRACT FROM AUTHOR]

Suspended single-walled carbon nanotubes (SWCNTs) offer unique functionalities for electronic and electromechanical systems. Due to their outstanding flexible nature, suspended SWCNT architectures have great potential for integration into flexible electronic systems. However, current techniques for integrating SWCNT architectures with flexible substrates are largely absent, especially in a manner that is both scalable and well controlled. Here, we present a new nanostructured transfer paradigm to print scalable and well-defined suspended nano/microscale SWCNT networks on 3D patterned flexible substrates with micro- to nanoscale precision. The underlying printing/transfer mechanism, as well as the mechanical, electromechanical, and mechanical resonance properties of the suspended SWCNTs are characterized, including identifying metrics relevant for reliable and sensitive device structures. Our approach represents a fast, scalable and general method for building suspended nano/micro SWCNT architectures suitable for flexible sensing and actuation systems. [ABSTRACT FROM AUTHOR]