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In this paper, systematic characterization of the dual probe, which is designed for the near field simultaneous measurement of both electric and magnetic field, is investigated with a microstrip line as the device under test (DUT). The characterization includes frequency response, transmission performance, symmetry, reflection, the intrusion of probe to the DUT, isolation of electric and magnetic field responses, field profile and spatial resolution, and differential electric field suppression. The dual probes with different design are adopted to demonstrate the systematic characterization.

In this paper, an ultrawideband differential magnetic near field probe with high electric field suppression is developed. A pair of differential loops, via fence and shielding vias below the loops are designed to reduce the electric field coupling. It is shown that the electric field suppression of the proposed magnetic-field probe is higher than 30 dB up to 12.9 GHz and 21 dB up to 14 GHz. Due to the differential loops and shielding vias, the proposed magnetic-field probe shows better electric field suppression and sensitivity performance, while maintaining similar spatial resolution. Two other probes with single loop for sensing and without shielding vias are prepared for comparison.

To measure the magnetic near field with high common-mode noise rejection, a probe with the differential and symmetrical structure forming a detection loop is developed. Such measurement is performed by using a two-port vector network analyzer (VNA) and validated by using a microstrip line as a device under test (DUT). In comparison to the measurement with traditional single-output magnetic near field probe, the electric field suppression of the proposed measurement can be improved by at least 10 dB in the frequency range of $3\sim 11$ GHz, while the other characteristics remain unchanged.

Extracting electromagnetic patterns by near field scanning can provide concrete information about a device under test (DUT), which benefits a lot when locating EMI sources. In this paper, we extracted the electromagnetic pattern of DUT under different operation state and classify the pattern with a machine learning algorithm for simplifying post-process procedure and better EMC engineering. The result showed different operation state lead to different electromagnetic emission.

In this paper, an experiment to distinguish the spatial resolution of different magnetic probes is executed. Different from traditional measuring method of spatial resolution by using one microstrip line, we measured the spatial resolution by changing two adjacent microstrip lines with space distances from 3 mm to 0.6 mm. By analyzing the test results, we can distinguish the spatial resolution of different probes.

The spatial resolution of probe is defined for a 6-dB level drop point from the peak point close to the edge of the microstrip line. However, this definition is not clear for strongly coupled traces. If the spacing between adjacent traces is small enough, the probe may not detect multiple sources. In this paper, near fields above differential microstrip lines are investigated numerically and theoretically for probe characterization of spatial resolution. Results show several limiting cases for the probe to discriminate two RF sources in close proximity. It is discovered that two traces can be easily distinguished with differential mode excitation, while the detection for the common mode excitation cases is affected by probe height and trace spacing.

In this paper, HPM is used as the source of interference to affect the working state of an integrated circuit. The effect of the injected power and the orientation of the studied integrated circuit (FPGA) is investigated. In the experiment, it is found that the induced voltage of the I/O pin can reach 70.3 V under the electromagnetic field high to 1257.44 V/m. In spite of this, the working state of the FPGA remained normal.

IgA nephropathy (Berger disease) is a disorder in which there is prominent IgA deposition in the glomerular mesangial area, and is the most common type of primary glomerulonephritis (1), receiving more and more attention (2-8). With diverse clinical manifestations, it has its own characteristic type of glomerular mesangial lesions (9).

The amiloride-sensitive epithelial sodium channel (ENaC), located in the apical membrane in the cortical collecting duct of the kidney, mediates the fine-tuned regulation of external Na+ balance. Expression of the alpha-subunit of ENaC (ENaC-α) is regulated by a number of factors in the lung, including transcription factor nuclear factor kappa B (NF-κB). In the present study, we examined the effect of IKKβ/p65/p50 on ENaC-α in a murine cortical collecting duct cell line that endogenously expresses ENaC, mpkCCDc14 (CCD) cells. Aldosterone exposure led to up-regulation of ENaC-α and IKKβ, and nuclear p65 and p50. Knockdown of IKKβ or p65 exhibited >60 % reduction of aldosterone-induced ENaC-α mRNA levels. Chromatin immunoprecipitation and electrophoretic mobility shift assays demonstrated a specific interaction between p65/p50 and ENaC-α gene promoter, which was further confirmed using luciferase reporter-gene vectors transiently transfected into CCD cells. Taken together these data support an important role for p65/p50 in the direct regulation of ENaC-α transcription and have important implications for understanding the role of NF-κB in the regulation of renal function.

Objective: The pathogenesis of progressive nephropathies involves inflammatory factors. The inhibition of cyclooxygenase-2 (COX-2) can limit renal damage and inflammation. However, the mechanism of up-regulation of COX-2 in nephropathy is poorly defined. Materials and methods: Here we found that tumor necrosis factor alpha (TNFα) was involved in expression of COX-2 in normal rat kidney (NRK) cell line. Results: TNFα stimulated COX-2 production in a time-dependent manner in NRK cells by inducing nuclear accumulation of RelB and nuclear factor kappa B2 (NF-κB2) and their association with COX-2 gene promoter. Depletion of IκB-inducing kinase alpha, a positive regulator of activation of p100 processing to active p52, attenuated TNFα-induced COX-2 production. Furthermore, TNFα induced COX-2 production and nuclear import in anti-thymocyte serum (ATS) nephropathy. Discussion and conclusion: These data suggest that TNFα-RelB/p52 pathway may be involved in the early stages of renal damage, in part by stimu...