Kuo-Shu Chen

Enhanced Particulate Organic Carbon Export at Eddy Edges in the Oligotrophic Western North Pacific Ocean

Mesoscale eddies in the subtropical oligotrophic ocean are ubiquitous and play an important role in nutrient supply and oceanic primary production. However, it is still unclear whether these mesoscale eddies can efficiently transfer CO2 from the atmosphere to deep waters via biological pump because of the sampling difficulty due to their transient nature. In 2007, particulate organic carbon (POC) fluxes, measured below the euphotic zone at the edge of warm eddy were 136–194 mg-C m−2 d−1 which was greatly elevated over that (POC flux = 26–35 mg-C m−2 d−1) determined in the nutrient-depleted oligotrophic waters in the Western North Pacific (WNP). In 2010, higher POC fluxes (83–115 mg-C m−2 d−1) were also observed at the boundary of mesoscale eddies in the WNP. The enhanced POC flux at the edge of eddies was mainly attributed to both large denuded diatom frustules and zooplankton fecal pellets based on scanning electron microscopy (SEM) examination. The result suggests that mesoscale eddies in the oligotrophic waters in the subtropical WNP can efficiently increase the oceanic carbon export flux and the eddy edge is a crucial conduit in carbon sequestration to deep waters.

Diagnosis of EMI to laptop WWAN device from TFT-LCD driver using non-contact measurement-based transfer function technique

This paper presents a novel non-contact measurement technique for electromagnetic interference (EMI) diagnosis. The proposed technique uses vector network analyzer with antenna and near-field probes to measure the transfer function for an EMI path without interrupting the operation of device under test. As an example, with the help of the measured transfer function and equivalent source in the proposed technique, the EMI to laptop wireless wide area network (WWAN) device caused by a thin film transistor-liquid crystal display (TFT-LCD) driver is accurately diagnosed and appropriately treated. In addition, an easy-to-follow procedure is given for applying the presented non-contact measurement technique to the demonstrated example.

Increased zooplankton PAH concentrations across hydrographic fronts in the East China Sea.

The Changjiang has transported large quantities of polycyclic aromatic hydrocarbons (PAHs) to the East China Sea (ECS), but information of these pollutants in zooplankton is limited. To understand PAHs pollution in zooplankton in the ECS, total concentrations of PAHs in zooplankton from surface waters were measured. Values of PAHs ranged from 2 to 3500 ng m(-3) in the ECS, with highest PAHs levels located at the salinity front between the Changjiang Diluted Water (CDW) and the mid-shelf waters. In contrast, concentrations of zooplankton PAHs in the mid-shelf and outer-shelf waters were significantly lower (2-23 ng m(-3)) than those in the CDW. These results demonstrate that PAHs are conspicuously accumulated in zooplankton at the salinity front between the CDW and the mid-shelf waters. These higher levels of PAHs in zooplankton at the salinity front may be further biomagnified in marine organisms of higher trophic levels through their feeding activities.

Prediction of common-mode radiated emission from PCB using vector network analyzer with a bulk injection current probe

This paper uses the vector network analyzer with a bulk injection current probe to measure the transmission coefficient for the common-mode radiated emissions from a printed circuit board. The purpose of developing such a measurement technique is to predict the far-field spectrum of radiated emission for good correlation with the fully-anechoic chamber measurement results. Electromagnetic simulation is also applied to verify the accuracy of the proposed technique. Comparison between simulation and measurement shows rather satisfactory agreement.

Arsenic and five metal concentrations in the muscle tissue of bigeye tuna (Thunnus obesus) in the Atlantic and Indian Oceans

White muscle concentrations of As, Cd, Cu, Fe, Se, and Zn were investigated in Atlantic- and Indian-bigeye tuna (BET) (Thunnus obesus) from 6 regions. As and Cd muscle concentrations were significantly higher in the Indian-BET than in the Atlantic-BET, whereas the Indian-BET caught in the waters off South Africa revealed the highest As, Se, and Zn muscle concentrations. Accordingly, multidimensional scaling separated them into two oceanic groups. Positive linear relationships between muscle Cd concentration and fork length (FL) were established in both oceans. For the other elements, only muscle-Fe and FL relationship was found in the Atlantic-BET. 10.3% of BET > 145 cm FL from both oceans possessed muscle Cd concentrations exceeding the food safety limit (0.1 μg g-1 wet weight) set by the European Commission. Increased Cd, Cu and Zn pollution was found in the Atlantic Ocean compared with previous data, with higher levels found in the Indian Ocean.

Corrigendum to “Nutrient supply in the Southern East China Sea after Typhoon Morakot”

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