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Photonic bandgap (PBG) structures can stop propagation of electromagnetic waves of certain frequencies and hence can be applied to construction of microstrip filters. In this paper, a novel PBG microstrip filter based on YBa/sub 2/Cu/sub 3/O/sub 7/ high-temperature superconductor films is presented. The PBG patterns forming the filters were etched on a 0.3- and a 0.7-/spl mu/m-thick film. Experimental results showed that the transmission coefficient S/sub 21/ of the filter is dependent on the thickness of the YBa/sub 2/Cu/sub 3/O/sub 7-x/ film. The thinner PBG filter exhibits an effective stopband of a center frequency of 20 GHz, a bandwidth of 4.7 GHz (at -40 dB), an attenuation of -55 dB, and a rolloff rate of 38 dB/GHz, while the thicker structure exhibits narrow notches only in the S/sub 21/ characteristics.

The power handling capability of high temperature superconducting (HTS) filters is limited due to current concentration at the edges of the superconducting films. This problem can be overcome by using ring resonator, which employs the edge current free and reduces the current concentration. However, this kind of filter has large size. In order to reduce the cost and size and increase the power handling capability, in this paper a HTS photonic bandgap (PBG) structure filter is developed. The proposed pass band filter with PBG structure exhibits center frequency 12.23 GHz, steepness (about 35 dB/GHz), bandwidth (−3 dB bandwidth is 0.045 GHz), and low insertion loss (about −0.5 dB), and can handle input power up to 1 W (this value was limited by the measurement instrument used in the experiment). The size is reduced by 25%, insertion loss reduced by 37.5%, and steeper roll-off of the filter is also obtained compared with that in published literature.

In this paper, a new method is presented for accurate analysis of interconnect trees. Based on the ABCD matrix of distributed RLC transmission lines, the new iterative method can derive the exact transfer functions of an interconnect tree with distributed RLC model. Moment matching and second-order approximation are used for fast simulation of time responses and 50% delays of interconnect trees. The new method has three advantages. First, it can calculate the exact transfer functions of an interconnect tree with any interconnect model besides distributed RLC model. Second, it can derive all leaf nodes' time-domain responses in one iterative process. Third, it runs faster than HSPICE with time complexity linearly proportional to the number of branches in an interconnect tree. Time-domain responses and 50% propagation delays of the new method are compared to the results of HSPICE, the Elmore delay for lumped RC trees, and equivalent Elmore delay for lumped RLC trees, showing that the new method is both accurate and fast.

In this paper the capacitance equivalent circuits of quasi-TEM HTS microstrip have been presented for thick and thin conductors according to the distribution of magnetic field and current density in superconducting thick and thin films, and the basic capacitance expressions have been given. The expressions are verified by using them to analyze three examples.

A superconducting microwave ring resonator whose resonant frequency can be tuned is designed and simulated. The structure is a ring resonator directly coupled to two low inductance open loops with Josephson junctions fabricated in a thin film format. The frequency tuning is accomplished by changing the nonlinear equivalent inductance of the Josephson junctions. The designed resonator works with higher Q value than that from other tuning approaches and with a frequency tuning range of 18%.

Background Abnormal activation of PI3K/AKT/mTOR (PAM) pathway, caused by PIK3CA mutation, KRAS mutation, PTEN loss, or AKT1 mutation, is one of the most frequent signaling abnormalities in breast carcinoma. However, distribution and frequencies of mutations in PAM pathway are unclear in breast cancer patients from the mainland of China and the correlation between these mutations and breast cancer outcome remains to be identified. Methods A total of 288 patients with invasive ductal breast cancer were recruited in this study. Mutations in PIK3CA (exons 4, 9 and 20), KRAS (exon 2) and AKT1 (exon 3) were detected using Sanger sequencing. PTEN loss was measured by immunohistochemistry assay. Correlations between these genetic aberrations and clinicopathological features were analyzed. Results The frequencies of PIK3CA mutation, KRAS mutation, AKT1 mutation and PTEN loss were 15.6%, 1.8%, 4.4% and 35.3%, respectively. However, except for PTEN loss, which was tied to estrogen receptor (ER) status, these alterations were not associated with other clinicopathological features. Survival analysis demonstrated that PIK3CA mutation, PTEN loss and PAM pathway activation were not associated with disease-free survival (DFS). Subgroup analysis of patients with ER positive tumors revealed that PIK3CA mutation more strongly reduced DFS compared to wild-type PIK3CA (76.2% vs. 54.2%; P = 0.011). PIK3CA mutation was also an independent factor for bad prognosis in ER positive patients. Conclusions AKT1, KRAS and PIK3CA mutations and PTEN loss all exist in women with breast cancer in the mainland China. PIK3CA mutation may contribute to the poor outcome of ER positive breast carcinomas, providing evidence for the combination of PI3K/AKT/mTOR inhibitors and endocrine therapy.

The heat treatment technique in sulfur-saturated vapor for ZnS : Mn thin films deposited by thermal evaporation is described in this paper. Results of Auger electron-spectroscopy (AES) and X-ray diffraction (XRD) analyses and the measurement of the energy gap show that thin films made in this way have better stoichiometric proportion and hexagonal system to meet the need of electroluminescent thin films.

In mixed-signal systems, effective noise isolation between analog and digital circuits is required for power integrity (PI). In this paper, Ferrite absorb material layer is deposited under the power plane to absorb high frequency noise from 500 MHz to 10 GHz. High dielectric constant nano BaTiO3 is used between the power plane and the ground for large buried capacitance to filter high frequency noise. First, noise isolation for High Dielectric Constant BaTiO3 Substrate is researched. Then, noise isolation for Ferrite Absorb Material researched. Third, the above two noise isolation are combined to form the designed technique. The designed power / ground structure from top to bottom is Power plane / Ferrite / nano BaTiO3 / Ground. The noise isolation is greatly improved for the designed power / ground structure than that for FR4 substrate without ferrite absorb material layer. In the mean time, the signal integrity effect is simulated, and the designed power / ground structure causes no signal integrity problem.

High-frequency (HF) attenuation of integrated electromagnetic interference (EMI) filter is determined by parasitics. The split ground structure is applied in this paper to realize parasitic capacitance cancellation, which resulted in expanded effective frequency range in common mode (CM) noise suppression. A simplified equivalent circuit is firstly derived and investigated to demonstrate the parasitic capacitance cancellation mechanism. Then design procedure with considered structural constraints is presented. Prototype of an integrated CM filter with split ground layers is finally designed and constructed. Experimental results show the resonance frequency of filter inductor is effectively shifted; hence better filtering characteristics can be achieved.

In this paper, an H-shaped power distribution network is designed based on constructal theory for EBG structure in PCB power plane, to optimize the direct current performance. EBG structures provide noise suppression performance and the network provides currents. This network is composed of hierarchical metal paths, and the geometric parameters can be optimized according to constructal theory. The optimal performance consists of constructing the giving area in a sequence of building blocks from the smallest size toward larger sizes hierarchically. In the meantime, a PCB power plane is developed based on the 2nd order H-shaped constructal network which illustrates that EBG power plane with H-shaped network has multifunctions of low voltage drop, current equidistribution and effective noise isolation.

In this paper, a novel structural winding arrangement is proposed to improve the high-frequency characteristics of the integrated EMI filter. Two ground winding layers are introduced to couple with common-mode (CM) choke winding to implement the CM capacitors so that the common mode EMI filter becomes a two-stage filter. Simulated by the Finite Element Analyze (FEA) software, the second resonance peak of transmission gain brought by the equivalent series inductance (ESL) is sharply decreased compared to the original structure to improve the high-frequency performance. In order to better analyze the proposed structure, the structural winding capacitance model of the planar spiral winding structure is given and the equivalent circuit is derived. Simulated and experimental results are included and they confirm the filtering effectiveness of the integrated planar EMI filter.

In this paper, a disc-shaped power tree is optimized by minimizing the overall resistance under the condition of the fixed entire disc area and the given tree structure. The resistance as function of geometry parameters and the pairing level n (complexity) is obtained. Then a disc power plane is designed based on the designed disc-shaped power tree. The DC performances for solid plane and the designed plane in this paper are compared. The research results illustrate that the designed disc power plane has multifunctions of equidistribution, low voltage drop, compactness and wideband noise isolation while maintaining a relatively simple design of geometry.

This paper proposes a hierarchical radial tree distribution network based on constructal theory for optimal direct current performance in printed circuit board power plane. The optimal radial tree dimensions of each order are obtained for optimal voltage drop and resistance. The constraints are the total areas of the plane and the high conductivity paths. The degrees of freedom are the width/length ratio H i /L i of the constructal block, high conductivity paths ratio D i+1 /D i (i=1, 2, etc). According to constructal theory, the optimal performance consists of constructing the giving area in a sequence of building blocks from the smallest size toward larger sizes hierarchically. High assembly level is not necessary. The optimal order is 12 for the designed tree. Then a radial PCB power plane is developed based on the radial tree which illustrates that the designed plane has multifunctions of low voltage drop, current robustness, equidistribution, compactness and effective noise isolation while maintaining a relatively simple design of geometry.

Microstrip multi-band bandstop filters using tri-mode equilateral triangular patch resonator are developed, and the rules of resonant frequency and patch defection dimension are obtained by calculation. With fractal patch defection and a higher substrate permittivity, higher order modes of resonator are activized for the multi-band implementation, and the dominant mode TM 1,0,−1 , and the higher order modes TM 1,1,−2 and TM 2,−2,0 are fully applied, and filter performances are greatly enhanced. The design is demonstrated by experiment. The proposed filters have advantages of simple topology, compact size and nicer performances, and all these features are well popular for wireless communication systems.

To investigate the effects of anluohuaqianwan on experimental hepatic fibrosis induced by dimethyl nitrosamine (DMN) in rats.36 male SD rats were randomly dividied into three groups: model group, normal group, anluohuaqianwan group. The rats in the three groups were treated with DMN daily for 4 weeks. The liver function was detected using auto biochemistry analyzer, the serum HA, LN, IV-C, PIIIP were detected by immunoradiometry, the histopathology was observed in the left liver lobe after HE staining, the expression of matrix metalloproteinase-2 (MMP-2) in liver tissue were detected by immunohistochemistry.The serum levels of ALT, AST, ALP, TP, ALB and the contents of HA, LN, IV-C in model group were significantly increased compared to these in the normal group (P less than 0.01). The serum levels of ALT, AST and the contents of HA in anluohuaqianwan group were significantly lower than those in the model group (P less than 0.01). The liver MMP-2 in the model group was significantly increased compared to that in the normal group (P less than 0.05). The expression of MMP-2 in liver tissue of model group was lower than that in the anluohuaqianwan group (P less than 0.05).Anluohuaqianwan can inhibit liver fibrosis in rats induced by DMN.

In this paper, novel fractal on chip power distribution technique has been developed. The novel structure is designed based on leaf vein. The simulated and measured results illustrate that our physical structure has greatly improved resistive and inductive voltage drop, and noise isolation between the analog and digital circuits.

In this paper, a novel fractal PCB power plane based on leaf vein fractal structure is developed. The technique introduced here not only provide noise suppression over a wide range of frequencies, but also improve IR drop and Swiss Chess structure effect (high resistance metal areas because of distributed vias and solders and leading to the voltages or currents to the circuit - elements lower than design demand).

In this paper, fractal power network has been proposed. The fractal structure is designed based on leaf vein. The simulated and measured results illustrate that the designed power network has greatly improved noise isolation, resistive and inductive voltage drop, and “Swiss Cheese” effect (There are many vias in the power plane just like many holes in Swiss Cheese. These via areas and their associated anti-pads forms high resistance areas and lead to the voltages or currents to the circuit — elements lower than design demand).

Currently, miniature microstrip filters with dual-mode operation have been widely studied and reported, however, numerous higher order modes are seldom used for a filter design. Multi-mode technique is regarded as one of the most effective methods for a bandpass filter with wideband and miniaturization implementation. This report presents bandpass filters with higher order mode and multi-mode operation by using single isosceles right-angled triangular patch resonator, and a single patch bandstop filter is also implemented. The new filters are some applications of right-angled triangular patch resonator which is of much less attention, and will be quite useful in modern RF circuits.

New equilateral triangular patch resonator bandpass filters using fractal defection are presented to implement high performances of wide passband, transmission zeros, and low passband insertion losses. Using fractal defection acts as perturbation, filter performances are greatly enhanced, and the validity of the design is demonstrated by measurement. Compared with some reported dual-mode or multi-mode filters, the new filters still have nicer performances even though operate at a single mode, simultaneously, have more compact and simple structures for having single patch resonator without coupling gaps.

A novel electromagnetic bandgap (EBG) of periodic rings etched on a YBCO microstrip line is presented and a minimized bandstop filter of high performance is obtained. In addition, this paper also develops a miniature EBG high temperature superconductors (HTS) disk filter with high power handling capability by etching five circular holes from a disc resonator.

Multi-mode technique has very important application in microwave filter design for implementing miniaturization, wide band and nicer performances. This report presents a new multi-mode bandpass filter with wide passband by using single isosceles right-angled triangular resonator which with much less attention, and transmission zeros and low passband insertion losses are obtained. The new filter has a novel, compact and simple structure as well as nicer performances, and can be quite useful in modern RF/microwave circuits and systems.

Fractal-shaped microwave passive circuits attract much attention recently. In this report, new planar bandpass filters with fractal patch defection by using equilateral triangular resonator and low permittivity substrate are presented to implement high performances of wide passband, transmission zeros, and low passband insertion losses. Using fractal defection acts as perturbation, single mode wideband bandpass filters are implemented, and filter performances are enhanced. Compared some reported dual-mode or multi-mode filters with the proposed ones, it shows the new filters have nicer performances even though operate at a single mode, simultaneously, posses compact and simple structures as well as miniaturization for having single patch resonator without coupling gaps. The advanced features of the proposed filters can be quite useful in wireless communication systems.

The design of power distribution network to deliver noise free power to high performance systems of increasing package density, high clock speed, high power demand at low voltages, and large current change with fast slew-rate is a challenging task. We design this novel structure according to a kind of plant leaf nutrient delivering system. There is good agreement between the numerical prediction method and the measurement results. The measured S21 is below -10 dB and SSN (simultaneous switching noise) cannot deliver into chip power system. The solders increase the DC (direct current) resistance 2.7% for the novel power-ground plane and 18.68% for traditional structure. The Swiss-Chess structure effect (high resistance metal areas because of distributed via and solders and leading to the voltages or currents to the circuit - elements lower than design demand) is reduced. The simulated gain shows there is no antenna effect for our designed power-ground plane.

Fractal-shaped microwave passive circuits attract much attention recently, but dominantly applied in antennas. In this report, new fractal bandpass filters using equilateral triangular patch resonator are presented to implement high performances of multi-transmission zeros, wide passband and stopband, and low passband insertion loss as well as miniaturization. Using fractal defection in patch, multi higher order modes are driven for coupling a much wider passband, and parasitical harmonics are effectively suppressed as well. Compared with some literatures, sizes of the new filters reduced and performances are greatly enhanced. The proposed filters have compact and simple structures, small sizes, high selectivity and so on, and all these features are the requirement of wireless communication systems.

The design of power distribution network to deliver noise free power to high performance systems of increasing package density, high clock speed, high power demand at low voltages, and large current change with fast slew-rate is a challenging task. This paper describes a novel power-ground plane design with low power supply noise, low radiation for modern system in package. We design this novel structure according to a kind of plant leaf nutrient delivering system because we think it works in the best way in nature. We wish deliver the direct current to each circuit element as the leaf delivers the nutrient with the least resistance. The designed power-ground plane structure consists of a power plane with perforation (top), and a ground plane (bottom). The size of the perforation is far below the wavelength in order that the existence of the perforated opening on the power planes contributes less to the radiation of the whole structure. There is good agreement between the numerical prediction method and measurement results. The measured S21 is below -10 dB and SSN (simultaneous switching noise) cannot deliver into chip power system. The solders increase the DC resistance 2.7% for the novel structure power plane-ground plane and 18.68% for traditional structure. The Swiss-Chess structure effect (high resistance metal areas because of distributed via and solders and leading to the voltages or currents to the circuit-elements lower than design demand) is reduced. The simulated gain shows there is no antenna effect for our designed power-ground plane.

Miniaturization is very important for modern communication systems. This paper presents new bandpass filters with low insertion loss and multi-band as well as wide stopband properties, and new bandstop filters with dual-rejectband and sharp attenuation to get nicer frequency selectivity by using miniature microstrip isosceles triangular resonator, and filter coupling schemes are given and discussed. Resonant equations obtained from EM simulation provide a quick, accurate and common way for helping design some of the filters. The designed filters meet the requirement of modern RF/microwave circuits and systems, and can be quite useful in future communication systems.

Triangular patch resonator bandpass filters with tunable operation are developed to perform nicer filter properties of low passband insertion loss, transmission zeros and wide stopband. With tunable fractal-shaped defection acts as perturbation, filter operation frequency and operation band can be controlled, and the responses of undesired resonant modes are greatly weakened even suppressed. The new design brings filter more function which does not require changing the dielectric substrate or patch size. The designed filters have outstanding advantages of single patch with compact size and without resonator coupling gaps, simple circuit topology, nicer performances, miniaturization and can be easily tuned for more applications. All these features are well popular for wireless communication systems.

In CMOS circuits, where consumption is not steady, current peaks produce voltage drops through the inductance, which manifest themselves as fluctuations in the internal supply voltages. This kind of noise is known as delta-I noise, simultaneous switching noise (SSN) or ground bounce. This paper describes a novel method to reduce the SSN: on-chip microstrip-mismatching technique in the power supply wire. The microstrip is connected with the bonding wire. The microstrip is embedded in Si dielectric upon Si substrate and does not increase the size of the chip. Not only the impedance mismatching technique between the bonding wire and the microstrip is considered in order to get noise source reflection coefficient |Gammag| = l at the end noise source-bonding wire, but also the microstrip length is properly designed to get source reflection coefficient Gammagout = -1 at the end microstrip and make the input impedance of the microstrip looking out from the CMOS unit at nodes p and n close to zero, thereby shortening out the noise voltage. Si has high dielectric constant and can also greatly attenuate the noise because of high dielectric loss. The results of S 21 depicts that the transmission coefficient is around -40dB. The technique developed in this paper has the advantage of simplicity, easy realization, non -oscillation and there is no size, weight and power dissipation penalties.

New microstrip low pass filters with low insertion loss, ultra-wide stopband and transmission zero are presented by using triangular and trapezoidal patch resonators with fractal defection. With such defection and a certain parallel feed method, undesired responses and harmonics are effectively suppressed and wide band, sharp attenuation obtained. The new filters have simpler and more compact configurations even better filter properties than the traditional line based ones.

H.C. Wu, Y J Cheng, G.A. Liang, H.F. Huang, K.Y. Wu, S.Y Chiang 1 School of Post Baccalaureate Chinese Medicine, China Medical University, 2 Department of Radiation Therapy and Oncology, China Medical University Hospital, 3 Institute of Chinese Medical Science, 4 Institute of Environmental Health and Occupational Medicine, National Health research Institute, Kaohsiung, 5 Department of Occupational Safety and Health

Two Chinese cases of Creutzfeldt-Jakob disease (CJD) are described which show the typical clinical, EEG and neuropathological changes of a subacute spongiform encephalopathy. One case was sporadic and the other was probably familial. This is the first formal report of CJD occurring in China.