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The human brain is divided into left and right hemispheres which show asymmetries in structure and function. This thesis developed state-of-the-art methods to extract a highly individualized and robust brain asymmetry feature based on the shape of the two hemispheres. This brain shape asymmetry can be used to identify individuals, much like a neuro-fingerprint. It is related to cognitive abilities, driven by environmental rather than genetic influences, and is disrupted in people with schizophrenia and Alzheimer’s disease.

In this paper we study the problem of extension of holomorphic sections of adjoint line bundles/vector bundles from reduced unions of strata of divisors. We prove a qualitative extension theorem for adjoint bundles. The main technical result is an extension theorem of the Ohsawa–Takegoshi type.

Additional file 1: Table S1. Adaptively convergent genes for nocturnal, foot-propelled diving or raptorial life history traits. Table S2. The total number of adaptively convergent site mutations (ACSMs) in adaptively convergent genes (ACGs) and the number of expected point mutations under neutral selection. Table S3. Sequence-convergent genes that show positive selection signals in parts or all of the foreground branches regarding nocturnal, foot-propelled diving or raptorial life history traits. Table S4. Adaptively convergent genes supporting for one of the derived convergence hypotheses (Hfoot-a, Hfoot-b, Hfoot-c, Hrap-a and Hrap-b, see Fig. 3). Figure S1. Maximum likelihood gene trees of 43 adaptively convergent genes, supporting one of the tree convergent hypotheses – nocturnality (Hnoc), foot-propelled diving (Hfoot) and raptorial behaviors (Hrap)

This paper describes the development of a silane-based Pd catalyst used as activator to replace the traditional Pd/Sn colloid for electroless nickel deposition onto a glass substrate. In this study, a styrene-co-γ-methacryloxypropyltrimethoxysilane oligomer (St-MPS) is synthesized by free radical polymerization method in acetone aqueous solution with potassium persulfate as the initiator firstly. The St-MPS oligomer can be used to reduce and stabilize Pd nanoparticles on the one hand. On the other hand, the hydrolysis and condensation reactions taking place between the silane units in St-MPS co-oligomers and glass substrate promote the adhesion of St-MPS/Pd catalyst and the subsequent nickel deposition. The adhesion strength is also demonstrated being affected by pre-heat conditions and thickness of Ni coating. Based on our results, a Ni layer with a thickness of 8.51 µm is obtained after plating for 60 min. The ink based on St-MPS/Pd colloids is successfully inkjet printed onto a glass substrate. The formed palladium layer is subjected to electroless nickel plating, yielding well-defined nickel pattern.

Table S1. Aboriginal rice accessions, control varieties and their domestication-related phenotypes. Table S2. Information on functionally characterized genes and mutations that underlie phenotypic changes during rice domestication. Table S3. Tribe, village and gender of informants. Table S4. Accessions used in the phylogenetic study, regions collected and their DNA accession numbers. Table S5. Primers used in the studies. (DOCX 67 kb)

Supplementary figures and methods. (PDF 884 kb)

Results of common seed analysis, pdf file format. (PDF 2900 kb)

Early detection of many fetal abnormalities is now possible due to the availability of antenatal ultrasound screening in the 12th to 16th week of gestation. Regarding urinary tract anomalies, most can be detected at 18–20 weeks of gestation. The incidence of antenatal hydronephrosis is 0.6–4.5%, and it makes up about 92% of antenatally-detected urinary tract anomalies. If antenatal hydronephrosis is detected, the patient should be carefully followed-up in order to identify the associated congenital anomaly. Usually, if the renal pelvic diameter exceeds 5 mm in the second trimester, then fetal ultrasonography should be repeated in the third trimester. Renal pelvic diameter greater then 7 mm is often related to a significant congenital anomaly; therefore, a plan for management after birth should be detailed. The newborn should be treated with prophylactic antibiotics and investigative imaging studies should be arranged accordingly.

A plastic, 95-GHz rectangular waveguide with an integrated plastic flange has been successfully demonstrated using micro hot embossing and electroplating technologies. Two prototype devices with integrated flanges on both ends have been tested using an Agilent PNA 5250 network analyzer. The prototype with non-metallized flange shows return loss s11 and insertion loss s21 values of −21.5 and −1.09 dB at 108 GHz, respectively with signal transmission rate at 77.8%. The prototype with metallized flange has s11 and s21 values of −31.5 dB and −0.7 dB, respectively, at 92.5 GHz, with signal transmission rate at 85%. The time domain measurement showed that the system losses are mainly due to the discontinuity losses at the interfaces between the network analyzer adaptors and the waveguide input/output ports. These losses could be further minimized in future integrated systems. As such, this new class of plastic waveguides has potential applications in replacing the expensive and bulky/heavy metallic waveguides in current millimeter-wave systems. © 2005 Elsevier B.V. All rights reserved.

Recent developments in micromachining techniques at the University of Michigan have resulted in novel high-performance low-loss filters for microwave and millimeter-wave applications. The idea is based on suspending the filters on thin dielectric membranes to eliminate dielectric loss and dispersion problems, resulting in a pure TEM mode of propagation and conductor-loss-limited performance. The dielectric membrane and the surrounding cavities are built using chemical etching in Silicon and GaAs wafers. The filters are therefore compatible with low-cost IC fabrication techniques and can be com- bined with planar diodes and transistors to result in active filter networks. Several state-of-the-art filters have been realized including 15-GHz and 20-GHz bandpass interdigi- tal suspended stripline filters, lowpass and bandpass microshield filters at 30 GHz and 90 GHz, microstrip 94-GHz bandpass filters, and a 250-GHz bandpass filter with 1.0-1.5-dB insertion loss. This article reviews the associated fabrication techniques, the different types of transmission lines achieved using this technology, and the measured performance from 15 to 350 GHz. The study concludes with a detailed description of the future work in this area. Q 1997 John Wiley & Sons, Inc. Int J Microwa'e Millimeter-Wa'e CAE 7: 149-166, 1997.

This paper reports on the design and performance of micromachined Lange-couplers and single-sideband mixers (SSB) on thin dielectric membranes at Ku-band. The micromachined Lange-coupler results in a 3.6/spl plusmn/0.8 dB coupling bandwidth from 6.5 to 20 GHz. The Lange-coupler and an interdigital filter are used in a 17-GHz SSB. The SSB mixer requires 1-2 mW of local oscillator (LO) power without dc bias and achieves a 30 dB upper-sideband (USB) image rejection for an IF frequency of 1 GHz and above. The micromachined membrane technology can be easily scaled to millimeter-wave monolithic microwave integrated circuits (MMIC's) to meet the low-cost requirements in automotive or portable communication systems.

We report on stripline resonators on thin dielectric membranes that show dispersion-free, conductor-loss limited performance at 13.5 GHz, 27.3 GHz, and 39.6 GHz. The unloaded-Q (Q/sub u/) of the resonators increases as /spl radic/f with frequency and is measured to be 386 at 27 GHz. The measured results agree well with a new conformal mapping analysis. The stripline resonators are used in a micromachined state-of-the-art planar interdigitated bandpass filter at K-band frequencies. Excellent agreement has been achieved between the microwave model at 850 MHz and the 20 GHz filter. The micromachined filter exhibits a passband return loss better than -15 dB and a conductor-loss limited 1.7 dB port-to-port insertion loss (including input/output CPW line loss) at 20.3 GHz.

Planar microwave and millimeter-wave inductors and capacitors have been fabricated on high-resistivity silicon substrates using micro-machining techniques. The inductors and capacitors are suspended on a thin dielectric membrane to reduce the parasitic capacitance to ground. The resonant frequencies of a 1.2 nH and a 1.7-nH inductor have been increased from 22 GHz and 17 GHz to around 70 GHz and 50 GHz, respectively. We also report on the design and measurement of a new class of stripline filters suspended on a thin dielectric membrane. Interdigitated filters with 43% and 5% bandwidth have been fabricated and exhibit a port-to-port 0.7 dB and 2.0 dB loss, respectively, at 14-15 GHz. The micro-machining fabrication technique can be used with silicon and GaAs substrates in microstrip or coplanar-waveguide configurations to result in planar low-loss lumped elements and filters suitable for monolithic integration or surface mount devices up to 100 GHz. >

The PDB (planar doped barrier) diode consists of a p/sup +/ doping spike between two intrinsic layers and n/sup +/ ohmic contacts. Such devices can have an anti-symmetric current vs. voltage characteristic. The capacitance is approximately constant with the applied voltage, and the barrier height and device capacitance are easily adjustable. These characteristics make the PDB a candidate for millimeter- and submillimeter-wave subharmonic mixers. We have fabricated 2 and 4 /spl mu/m diameter diodes with different barrier designs using GaAs epi-layers. The devices are planarized using an air-bridge and a surface channel etch. After completely removing the substrate, the devices are mounted on a quartz substrate to reduce parasitic effects. Diced diodes were tested as subharmonic mixers around 200 GHz in both a quasi-optical planar wideband subharmonic receiver and a planar-diode waveguide-mixer. The quasi-optical measurements show that a 0.23 V (and 0.4 V) barrier height GaAs diode with 2.0 /spl mu/A (and 5 nA) of saturation current gives a DSB conversion loss of 10.8 dB (and 9.5 dB) and a DSB noise temperature of 3795/spl deg/ K and 2450/spl deg/ K). The waveguide mixer measurements were made with a similar 0.23 V barrier height PDB. Such a mixer has a minimum conversion loss of 10.2 dB and noise temperature of 3570/spl deg/ K, and requires only 1.2 milliwatts of available LO power. >

We present for the first time a quasi-optical mixer realized as a resistive HFET mixer with an integrated slot antenna. Two different types of HFET's, based on GaAs and InP, are compared for this application. The mixer conversion loss, defined as the measured IF power in the 50 /spl Omega/ load divided by the RF power available at the slot-antenna terminals, is better than 7 dB at LO powers down to 0 dBm. Subharmonic pumping of the mixer is also investigated. This topology has a potential interest for future low-cost millimeter-wave receivers for automobile radar and speed detector systems. >

Given a projective variety X, a smooth divisor D, and semipositive line bundles (L_1,h_1),,...,(L_m,h_m), we consider the "multiply twisted pluricanonical bundle" F:=m(K_X+D)+L_1+...+L_m on X and F_D:=mK_D+(L_1+...+L_m)|_D. Let I_j be the multiplier ideal sheaves associated to h_j, j=1,...,m. We show that, under a certain conditions on curvature, H^0(D,F_D\otimes I_1I_2...I_m) lies in the image of the restriction map H^0(X,F)->H^0(D,F_D). The format of our result is inspired both by Paun's simplification of Siu's proof of invariance of plurigenera and an earlier similar result due to Demailly. The main ingredient is a modification of Siu-Paun's induction construction and an extension theorem of Ohsawa-Takegoshi type (O-T). We also include a detail proof of O-T. The key feature is that the ideal sheaf we use is the product of the multiplier ideals associated to the singular metrics h_1,...,h_m, which contains the multiplier ideal sheaf of the product of the metrics h_1\otimes...\otimes h_m., 26 pages

Recently, millimeter-wave devices have been attracted more attentions in applications owing to their short wavelengths, higher resolutions, broader bandwidths and higher environmental tolerance. The great challenges of high fabrication and assembly costs, bulky volumes, and heavy weights of millimeter-wave systems call for new integrated manufacturing techniques. The hot embossing technique could address these challenges. In this paper, a review of micro plastic hot embossing was given for the fabrication of miniaturized millimeter-wave systems. The micro hot embossing on plastic materials demonstrated its advantages on significant costs, volume and weight reduction, while maintaining high performances. We have designed, fabricated and characterized a W-band rectangular waveguide and a W-band iris waveguide filter with integrated plastic flanges using micro hot embossing and selective electroplating. In this paper, we reviewed the results and discussed the design methodology in details for the micromachined components. The prototype devices showed promise for the system designs.

A plastic, 95-GHz rectangular waveguide with an integrated plastic flange has been successfully demonstrated using micro hot embossing and electroplating technologies. The prototype device shows s/sub 11/ and s/sub 21/ values of -20.7 dB and -1.35 dB at 95GHz, respectively, and the signal transmission rate is 73.3% as compared to commercial all-metal waveguides at 85%. The time domain measurement showed the system losses are mainly due to the discontinuity losses at the interfaces between the network analyzer adaptors and the waveguide input/output ports and could be further minimized in future integrated systems. As such, this new class of plastic waveguides has potential applications in replacing the expensive yet bulky/heavy metallic waveguides in current millimeter-wave systems.

A micromachined W-band iris filter was successfully demonstrated using micro hot embossing and selective electroplating technologies. The filter design follows the insertion loss method with a Chebyshev polynomial to synthesize the desired spectral responses and numerical simulations were performed using the finite-element tool, high frequency structure simulator (HFSS), to study the effects of iris thickness on the bandwidth and center frequency. The measured prototype filter performance has a transmission loss of -3.49 dB and a return loss of -18 dB at the resonant frequency of 95 GHz. The filter has a bandwidth of 3.5 GHz and a rejection loss of better than -50 dB, while the loaded quality factor is 27.27. This plastic, low-cost manufacturing process opens up opportunities in replacing the expensive metallic components and integrated 3D manufacturing for current and future millimeter-wave systems.

Subharmonically pumped mixers using zero-biased anti-parallel Schottky diode pairs produce good results, but require a larger LO power than biased Schottky diodes. Presented here is a novel planar-diode anti-parallel pair that allows independent biasing of the two diodes. This diode pair is integrated into a quasi-optical wideband receiver and the RF measurements on a 1.2-/spl mu/m anode diameter pair show a reduced LO power requirement at 180 GHz by a factor of 2 to 3 with a similar DSB conversion loss and noise temperature (9.7 dB and 1850 K) to an unbiased Schottky diode pair. This structure has potential for applications at submillimeter-wave frequencies where a large amount of LO power is not easily available. >

We present for the first time a quasi optical mixer realized as a resistive HFET mixer with an integrated slot antenna. The mixer circuit conversion loss, defined as the measured IF-power in the 50 ohm load divided by the RF-power available at the slot-antenna terminals, is approximately 7 dB at an LO-power of 10.5 dBm when the mixer is fundamentally pumped, and 16 dB for subharmonically pumping at 10 dBm LO-power. >

A novel quasi-optical planar subharmonically pumped receiver including a log-periodic antenna and an anti-parallel Schottky diode pair with independent bias is presented. The antenna and Schottky diode pair have a 20 /spl mu/m and 2.5 /spl mu/m wide split, respectively, for biasing considerations and an overlay capacitor for RF coupling. Millimeter-wave measurements at 91 GHz show that, at /spl plusmn/0.4 V bias, the separately biased subharmonic mixer requires 2-3 times less LO power than the zero-biased subharmonic mixer for the same 8 dB (SSB) conversion loss. At 180 GHz a similar LO power requirement reduction has been achieved, with a minimum conversion loss of 9.7 dB and noise temperature of 1850 K (DS8). >

Planar millimeter-wave microstrip inductors and capacitors have been fabricated on high-resistivity silicon substrates using micro-machining techniques. The spiral inductors and interdigitated capacitors are suspended on a thin dielectric membrane to reduce the parasitic capacitance to ground. The resonant frequencies of a 1.2 nH and a 1.7 nH inductor fabricated on a high-resistivity silicon substrate and on a small dielectric membrane, have been increased from 22 GHz and 17 GHz to 73 GHz and 54 GHz, respectively. The planar micro-machined elements are compatible with the via-hole technology process in GaAs and InP MMIC, and can be used as true inductors and capacitors up to 50-60 GHz. The technique can be also applied to lumped elements in coplanar-waveguide transmission lines. >

The extrinsic transconductance of a PHEMT device is examined using a rigorous isothermal pulsed I-V technique. The extrinsic transconductance is determined directly from the pulsed I-V (gm pulsed) measurements and compared with pulsed S-parameter measurements (gm RF). The discrepancy between gm pulsed and gm RF for the Vgs range of -1.0 to -0.4 is less than 10%. Transconductance extracted from the conventional DC I-V measurements (gm DC) differs by greater than 35% from the gm RF values over this same Vgs range.

We report on the results of a state-of-the-art planar interdigitated bandpass filter at K-band by using micromachining techniques. In this design, a microwave model was first built at 850 MHz to simulate the K-band filter, and the 20 GHz micromachined filter was fabricated based on the 850 MHz microwave model. Excellent agreement has been achieved between the microwave model and the 20 GHz filter. The micromachined filter exhibits a return loss better than -15 dB within the passband and a 1.7 dB port-to-port insertion loss at 20.3 GHz. A grounded coplanar waveguide with a micromachined mouse-hole shielding structure has also been carefully examined. The grounded coplanar waveguide structure is used in the micromachined filter as the input/output feeding line and exhibits a return loss better than -20 dB up to 32 GHz. >

A quasi-optical amplifier suitable for Gaussian-beam applications is presented. The amplifier is based on the integrated horn antenna and uses polarization duplexing to isolate the output beam from the input beam. A prototype hybrid amplifier is reported with a measured gain of 10.5 dB at 5.92 GHz. The amplifier design is uniplanar, is compact, and is compatible with the fabrication process of high-electron-mobility transistors (HEMTs) at millimeter-wave frequencies. >

We report on the design and measurement of a new class of stripline filters for millimeter-wave applications. The novelty in this work is to suspend the interdigitated lines on a thin dielectric membrane to eliminate the dielectric losses and to render the interdigitated filter physically realizable at millimter-wave frequencies. A wide band filter with a center frequency of 13.7 GHz and a bandwidth of 45% has been fabricated. The filter exhibits a port-to-port insertion loss of 0.7dB at 13.7 GHz. This fabrication technique can be easily used at higher frequencies to result in planar low loss filters suitable for monolithic integration or surface mount devices up to 40-60 GHz.

The discovery of the causative gene for Huntington's disease (HD) has promoted numerous efforts to uncover cellular pathways that lower levels of mutant huntingtin protein (mHtt) and potentially forestall the appearance of HD-related neurological defects. Using a cell-based model of pathogenic huntingtin expression, we identified a class of compounds that protect cells through selective inhibition of a lipid kinase, PIP4Kγ. Pharmacological inhibition or knock-down of PIP4Kγ modulates the equilibrium between phosphatidylinositide (PI) species within the cell and increases basal autophagy, reducing the total amount of mHtt protein in human patient fibroblasts and aggregates in neurons. In two Drosophila models of Huntington's disease, genetic knockdown of PIP4K ameliorated neuronal dysfunction and degeneration as assessed using motor performance and retinal degeneration assays respectively. Together, these results suggest that PIP4Kγ is a druggable target whose inhibition enhances productive autophagy and mHtt proteolysis, revealing a useful pharmacological point of intervention for the treatment of Huntington's disease, and potentially for other neurodegenerative disorders.