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The 5G products and service with widened band and high frequency including mm wave have been commercially started. General dielectric materials like polyimides or epoxy resins have large transmission loss in high frequency region. The loss is divided into mainly two factors, dielectric loss and conductor loss. In order to reduce the transmission loss, dielectrics need to have lower dissipation factor and conductor such as copper foil needs to have lower surface roughness. Thus, we simulate the impact of dielectric loss by dissipation factor and conductor loss by surface roughness on transmission loss. Furthermore, we experimentally confirmed the accuracy of the simulation by the transmission measurement with various core films. The simulation revealed that applying lower dissipation factor of core film is the most effective method to reduce the transmission loss. Simulation and experiment of transmission loss trend are well matched with multi-layer dielectrics. From such knowledge, we have developed new dielectric materials with low dissipation factor along with strong adhesion to copper foil with smooth surface. Adhesive usually needs to have polar chemical structure for better adhesion yet the polarity tends to increase dielectric constant and loss tangent. Therefore, satisfy adhesion and low dielectric constants at the same time was difficult. Recent work at JSR discovered a chemical structure that keep dielectric constants low while exhibit polarity, which enhances adhesion. This new material can be used as an adhesive between polyimide and copper foil with smooth surface. Flexible printed circuit was fabricated using our new adhesive along with the conventional polyimide film and copper foil with smooth surface. Measurement of transmission line of the circuit revealed significant improvement of transmission loss at mm wavelength range. We hereby report the details of the simulation and measurement results of the novel dielectric adhesive with low loss tangent.

Psychological stress induces many diseases including post-traumatic stress disorder (PTSD); however, the causal relationship between stress and brain atrophy has not been clarified. Applying single-prolonged stress (SPS) to explore the global effect of severe stress, we performed brain magnetic resonance imaging (MRI) acquisition and Voxel-based morphometry (VBM). Significant atrophy was detected in the bilateral thalamus and right visual cortex. Fluorescent immunohistochemistry for Iba-1 as the marker of activated microglia indicates regional microglial activation as stress-reaction in these atrophic areas. These data certify the impact of severe psychological stress on the atrophy of the visual cortex and the thalamus. Unexpectedly, these results are similar to chronic neuropathic pain rather than PTSD clinical research. We believe that some sensitisation mechanism from severe stress-induced atrophy in the visual cortex and thalamus, and the functional defect of the visual system may be a potential therapeutic target for stress-related diseases.

This paper reports the scheme of a research project funded by the Ministry of Land， Infrastructure， Transport and Tourism (MLIT) from the fiscal year of 2012 to 2014 under the title of "Development of base isolation device complied with the ultimate strength design code." The theoretical prediction tells us a new approach to develop a highly stable laminated rubber bearing that has a constant buckling load even under large lateral displacement. Relatively high shear stiffness makes it more stable and the height of the bearing should be longer than its diameter. They are the newly discovered theoretical buckling stability criteria from the previous studies conducted by the author’s research team. The experimental studies in this project show the compatibility with the theoretical prediction and highly linear loaddisplacement relationship under large deformation. The performance of the newly developed device satisfies the requirement of the ultimate strength design code, if the ground condition of the target building is normally solid enough to prevent liquefaction. The theoretically predicted buckling stability of the laminated rubber bearings has been experimentally verified by the specimens of this project.

In the Kashiwazaki-Kariwa Nuclear Power Station, the seismic ground motion in the south side of the site, was significantly larger than that in the north side of the site, in the 2007 Niigataken Chuetsu-oki earthquake. In order to analyze the effects of geological structure below the site on the seismic ground motion characteristics in the site, we made 2-D soil model and simulated the seismic ground motion with the model using the finite difference method. The soil model was estimated by the result of the geological investigations and described the folding structure just below the Kashiwazaki-Kariwa Nuclear Power Station. For input motion, we defined point source or plane wave, and we considered many directions as the incidence angle. From the result of analysis, we concluded that seismic wave concentrated in the local area of the site with the influence of the complex ground structure, and the ground motion in the south side became larger than that in the north side.

This paper investigates factors causing difference of site amplification in the Kashiwazaki-Kariwa Nuclear Power Station in the 2007 Niigataken Chuetsu-oki earthquake. To consider 3D response by asperities outside the section of 2D folded structure, FEM analysis is performed with vertical and horizontal incident angles. At Unit 1 above syncline, amplification of 2D model is larger than that of 1D model directly under the point when incidence is closer to vertical as the third asperity. This is due to folds of both first and second boundaries. At Unit 5 above anticline, amplification of 2D model corresponds to that of 1D model.

Nanoporous (np; 5-50 nm in pore diameter) Al2O3 was investigated as a matrix for a fluid catalytic cracking (FCC) catalyst as either a binder or a catalytic site using model compounds as feedstock to achieve not only high activity, but also less coking. The binder characteristics of np Al2O3 matrix were expected to increase the mechanical strength and hydrothermal resistance of the catalyst, because np Al2O3 from unimodal and non-aggregated boehmite sols has better mechanical strength than np Al2O3 from aggregated boehmite gels and can protect the zeolite component from hydrothermal degradation during catalyst regeneration more than np SiO2. Application of np Al2O3 with controlled crystallite and pore sizes as an active matrix for catalytic cracking resulted in less coking, which indicated that np Al2O3 has an important role as a pre-cracking agent. A np Al2O3 matrix with a pore size diameter of ca. 11-15 nm was found to be optimum for a catalytic cracking catalyst.

Strong motion records of 2007 Niigata-ken Chuetsu-oki earthquake were examined in order to evaluate ground motion characteristics of the earthquake. Ground motions observed at Kashiwazaki Kariwa Nuclear Power Plant site were significantly larger than the response spectra evaluated on the basis of Noda et al. (2002), and the level of the ground motion observed at Arahama area (unit 1-4 side) was approximately twice as large as that at Ominato area (unit 5-7 side). Observation records of the offshore events other than the eathquake were also larger than the response spectra based on Noda et al. (2002), whereas records of the inland events were smaller than those. In addition, these characteristics were also observed in the vicinity of the site through the analysis of the ground motion records obtained by KiK-net.

This paper discusses the stability of laminated rubber bearings with high damping materials both theoretically and experimentally. The specimens adopted for this study were tested under static loading before shaking table tests were conducted to check their dynamic stability. As a result of the static loading test we have obtained the fact that the geometrical nonlinearity can be separated from the material nonlinearity under large deformation. The shaking table tests also support the stability criterion that is predicted from the geometrical nonlinear theory, which has been proved by the static loading tests in the previous studies. This paper successfully explains the coherence between the experimental results and the theoretical predictions expected from the rigorous solutions based on the nonlinear model we have developed in the previous study.

The theoretical predictions brought into discussion by author's previous papers motivated us to carry out a series of experimental studies on the load-displacement behavior of laminated rubber bearings in an excessively large deformation. One of the key issues intrigued us is that the slenderness of the specimen plays an important role to stabilize the buckling behavior even under extreme circumstances of large deformation. Another issue also interesting and important is the shear stiffness associated with the rubber has a vital effect on the stability of the bearings in a large deformed shape. The result of the experiments strongly supports the theoretical predictions and it unveiled the superbly stable load supporting capacity latent in the laminated rubber bearings with rather slender configuration.

Leading edge semiconductor products are made by immersion lithography at 193 nm using water as a fluid medium. This imaging process enables production of 45 nm features. Extending immersion lithography to 32 nm or below requires increases in the refractive indices of the lens material, the immersion fluid, and the resist material. Future generations of resist materials require a refractive index approaching 1.9 at 193 nm. It is known that incorporation of sulfur atoms increases the refractive index of polymers. However, increasing the refractive index is normally linked to a corresponding increase in the absorbance. In attempt to design resist polymers with a high refractive index and low absorbance, we studied several new sulfur-containing monomers and polymers and found functionality that can increase the refractive index without increasing the absorbance at 193 nm. New thioester and sulfone structures are particularly useful in that regard. These new monomers have been used produce imageable polymers with a refractive index of 1.8 at 193 nm and an absorbance less than 1.4 μm -1 .

Necdin, a member of the MAGE family, is expressed abundantly in postmitotic neurons and is required for their differentiation and survival. In mammals, the MAGE family consists of more than 30 genes, whereas only one MAGE gene exists in the genome of nonmammalian vertebrates such as zebrafish and chicken. These nonmammalian MAGE genes are expressed in developing nervous system, and the primary structures of the encoded proteins resemble those of necdin-like MAGE proteins. Fruit fly Drosophila also carries a single necdin-like MAGE gene, which is highly expressed in neural stem cells (neuroblasts) during nervous system development. In the present study, we investigated the function of MAGE in Drosophila neurogenesis in vivo using an RNA interference (RNAi) -mediated gene knockdown system. Ubiquitous knockdown of Drosophila MAGE by double-stranded RNA injection into embryos was lethal at early stages of organogenesis. MAGE was then knocked down in developing mushroom bodies by RNAi-mediated gene silencing using the OK107-GAL4 driver. MAGE RNAi increased the population of proliferative neural precursors in larval mushroom bodies. At the pupal stage, RNAi-mediated MAGE knockdown led to a significant enlargement of the mushroom bodies as a result of increased neuronal population, presumably by accelerating the asymmetric division of neural stem cells. MAGE RNAi mushroom bodies of adult flies showed neurodegenerative changes such as vacuolation and nuclear DNA breaks, implying that supernumerary neurons undergo apoptosis during postpupal development. These results suggest that evolutionally conserved necdin-like MAGE is involved in both neural stem cell proliferation and neuronal survival during nervous system development.

The synthesis and photopolymerization of alkaline-developable hyperbranched polyurethane (HBPUMA-COOH) were examined. The reaction of dicyclohexylmethane 4,4‘-diisocyanate (CMDI) and trimethylolpropane (TMP) in the presence of 2-methacryloyloxyethyl isocyanate (MOI) was carried out to give the soluble hyperbranched polyurethane (HBPUMA) with terminal methacryloyl groups in satisfactory yield. After that, HBPUMA-COOH was synthesized by the reaction of HBPUMA and cis-1,2,3,6-tetrahydrophthalic anhydride (THPA). The photoradical polymerization of HBPUMA-COOH was examined in the presence of 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-2-one (Irgacure 907) as a photoinitiator in the film state upon UV irradiation to afford the corresponding cured film quantitatively. It was found that the tensile strength of the resulting cured film of HBPUMA-COOH was higher than those of the HBPUMA and linear one. The negative patterning property of HBPUMA-COOH also had 5 μm line and space pattern resolution by UV irr...

Necdin, a member of the MAGE (melanoma antigen) protein family, is expressed predominantly in terminally differentiated neurons. The necdin geneNDNis maternally imprinted and expressed only from the paternal allele, the deficiency of which is implicated in the pathogenesis of the neurodevelopmental disorder Prader-Willi syndrome. Necdin binds to its homologous MAGE protein MAGE-D1 (also known as NRAGE or Dlxin-1), which interacts with Msx (msh homeobox) and Dlx (distal-less homeobox) family homeodomain transcription factors. Members of the Dlx homeobox gene family are involved in the differentiation and specification of forebrain GABAergic neurons. Here we demonstrate that necdin associates with Dlx homeodomain proteins via MAGE-D1 to promote the differentiation of GABAergic neurons in mouse embryonic forebrain. Immunohistochemical analysis revealed that necdin was coexpressed with Dlx2, Dlx5, or MAGE-D1 in a subpopulation of embryonic forebrain cells. Necdin bound to Dlx2 and Dlx5 via MAGE-D1 and enhanced Dlx2-dependent activation of the Wnt1 (wingless-type MMTV integration site family) promoter. Necdin significantly increased the populations of cells expressing the GABAergic neuron markers calbindin D-28k and glutamic acid decarboxylase when overexpressed by electroporation in cultured forebrain slices. In this assay, Dlx5N, a truncated Dlx5 mutant that competes with Dlx2 to bind MAGE-D1, diminished the effect of necdin on GABAergic neuron differentiation. Furthermore, mutant mice lacking the paternal necdin allele showed a significant reduction in the differentiation of forebrain GABAergic neuronsin vivoandin vitro. These results suggest that paternally expressed necdin facilitates the differentiation and specification of GABAergic neurons in cooperation with Dlx homeodomain proteins.

The syntheses and properties of hyperbranched poly(o-hydroxyamide) [poly(HAB-BCC)-ABP], poly[o-(t-butoxycarbonyl)amide] [poly(HAB-BCC)-ABP-t-BOC], and polybenzoxazole [poly(HAB-cycloBCC)] were examined. Poly(HAB-BCC)-ABP was obtained from the polycondensation reaction of 3,3-dihydroxy-4,4′-diaminobiphenyl (HAB) as an A2-monomer and 1,3,5-benzenetricarboxylchloride (BCC) as a B3-monomer with 2-amino-4-t-butylphenol (ABP) in NMP in the presence of pyridine for 24 h. The reaction of poly(HAB-BCC)-ABP and di-t-buthylcarbonate (DiBOC) was performed to obtain the corresponding poly(HAB-BCC)-ABP-t-BOC with pendant t-BOC groups. The thermal cyclodehydration of poly(HAB-BCC)-ABP-t-BOC was carried out in the film sate at 400 °C, affording the poly(HAB-cyclo-BCC) in quantitative yield. Furthermore, the solubilities and thermal properties of these polymers were examined. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3640–3649, 2006

Necdin is a multifunctional signaling protein that stabilizes terminal differentiation of postmitotic neurons. The human necdin gene in chromosome 15q11-q12 is maternally imprinted, paternally transcribed, and not expressed in Prader-Willi syndrome, a human genomic imprinting-associated neurodevelopmental disorder. Although necdin-deficient mice display several abnormal phenotypes reminiscent of this syndrome, little is known about molecular mechanisms that lead to the neurodevelopmental defects. Here, we demonstrate that paternally expressed necdin is required for physiological development of nerve growth factor (NGF)-dependent sensory neurons. Mouse embryos defective in the paternal necdin allele displayed absent necdin expression in the dorsal root ganglia, in which the tropomyosin-related kinase A (TrkA) receptor tyrosine kinase and the p75 neurotrophin receptor were expressed in a normal manner. Necdin interacted with both TrkA and p75 to facilitate the association between these receptors. NGF-induced phosphorylation of TrkA and mitogen-activated protein kinase was significantly diminished in the necdin-null sensory ganglia. Furthermore, the mice lacking the paternal necdin allele displayed augmented apoptosis in the sensory gangliain vivoand had a reduced population of substance P-containing neurons. These mutant mice showed significantly high tolerance to thermal pain, which is often seen in individuals with Prader-Willi syndrome. These results suggest that paternally expressed necdin facilitates TrkA signaling to promote the survival of NGF-dependent nociceptive neurons.

In this paper, we describe the syntheses, properties, and photo-induced deprotection of β-CD derivatives containing t-butyl ester groups and fluorine atoms. The β-CD derivative was obtained from th...

We have previously reported that overexpression of wild-type amyloid precursor protein (APP) in postmitotic neurons induces cleavage-dependent activation of caspase-3 both in vivo and in vitro. In this study, we investigated the mechanism underlying APP-induced caspase-3 activation using adenovirus-mediated gene transfer into postmitotic neurons derived from human embryonal carcinoma NT2 cells. Overexpression of wild-type APP significantly increased intracellular (45)Ca(2+) content prior to the activation of caspase-3 in NT2-derived neurons. Chelation of intracellular Ca(2+) markedly suppressed APP-induced activation of caspase-3. Furthermore, calpain, a Ca(2+)-dependent cysteine protease, was activated in neurons overexpressing APP as assessed by increased levels of calpain-cleaved alpha-fodrin and autolytic mu-calpain fragments. Neither calpain nor caspase-3 was activated in neurons expressing an APP mutant defective in the Abeta(1-20) domain. Calpain inhibitors almost completely suppressed APP-induced activation of neuronal caspase-3. E64d, a membrane permeable inhibitor of calpain, significantly suppressed APP-induced neuronal death. These results suggest that overexpression of wild-type APP activates calpain that mediates caspase-3 activation in postmitotic neurons.

Necdin is expressed predominantly in postmitotic neurons and serves as a growth suppressor that is functionally similar to the retinoblastoma tumor suppressor protein. Using primary cultures of dorsal root ganglion (DRG) of mouse embryos, we investigated the involvement of necdin in the terminal differentiation of neurons. DRG cells were prepared from mouse embryos at 12.5 days of gestation and cultured in the presence of nerve growth factor (NGF). Immunocytochemistry revealed that necdin accumulated in the nucleus of differentiated neurons that showed neurite extension and expressed the neuronal markers microtubule-associated protein 2 and synaptophysin. Suppression of necdin expression in DRG cultures treated with antisense oligonucleotides led to a marked reduction in the number of terminally differentiated neurons. The antisense oligonucleotide-treated cells did not attempt to reenter the cell cycle, but underwent death with characteristics of apoptosis such as caspase-3 activation, nuclear condensation, and chromosomal DNA fragmentation. Furthermore, a caspase-3 inhibitor rescued antisense oligonucleotide-treated cells from apoptosis and significantly increased the population of terminally differentiated neurons. These results suggest that necdin mediates the terminal differentiation and survival of NGF-dependent DRG neurons and that necdin-deficient nascent neurons are destined to caspase-3-dependent apoptosis.

To elucidate the mechanism of neuronal death in Alzheimer's disease, we investigated the effects of overexpression of wild-type Alzheimer amyloid precursor protein (APP) on neuronal cells and glial cells in vivo. When an APP695-expressing adenovirus was injected into the dorsal hippocampal region, a number of neurons in remote areas were positively stained with anti-APP monoclonal antibody, and underwent severe degeneration from 3 to 7 days after viral inoculation. Most degenerating neurons were immunopositive with both APP and activated caspase-3, but some neurons that expressed activated caspase-3 were not expressing APP from 7 to 14 days after virus injection. In the neighborhood of the degenerating neurons, activated microglia/macrophages, which were identified by the phenotypic marker C3bi receptor (CD11b/c; OX-42), were observed, and some of them appeared to phagocytose the caspase-3-immunopositive degenerating neurons. In addition to microglia/macrophages, infiltrating leukocytes expressing CD45 or CD4 were also detected. These results suggest that the increased accumulation of APP induced not only caspase-3-mediated death machinery, but also inflammatory responses including microglial activation. These inflammatory responses might cause further neurodegeneration through the alternative pathway that might activate the caspase-3-mediated death machinery without APP expression.

Forced overexpression of wild-type Alzheimer amyloid precursor protein (APP) causes postmitotic neurons to degenerate. Caspase-3 (CPP32) is a principal cell death protease involved in neuronal apoptosis during physiological development and under pathological conditions. Here, we investigated whether APP overexpression activates caspase-3 in human postmitotic neurons using adenovirus-mediated gene transfer. When a recombinant adenovirus vector expressing human wild-type APP695 was infected in vitro into neurally differentiated embryonal carcinoma NT2 cells, only postmitotic neurons underwent severe degeneration. Before neurodegeneration, full-length APP- and Abeta-immunoreactive peptides were accumulated in infected neurons, and caspase-3-like protease activity was markedly elevated. Western blot analysis revealed that activated caspase-3 subunits were generated in APP-accumulating neurons. Such neuronal caspase-3 activation was undetectable in NT2 neurons infected with beta-galactosidase-expressing adenovirus. Addition of the caspase-3 inhibitor acetyl-Asp-Glu-Val-Asp-aldehyde to the culture medium significantly reduced the severity of degeneration exhibited by APP-overexpressing neurons. Immunocytochemical analyses revealed that some APP-accumulating neurons contained activated caspase-3 subunits and exhibited the characteristics of apoptosis, such as chromatin condensation and DNA fragmentation. Activation of caspase-3 was also observed in vivo in rat hippocampal neurons infected with the APP-expressing adenovirus. These results suggest that wild-type APP is an intrinsic activator of caspase-3-mediated death machinery in postmitotic neurons.

This paper reviews an active control algorithm adopted for an active-passive composite tuned mass damper, which is a unique vibration control device equipped into an office building in Tokyo in 1993. The main purpose of this device is to subdue the response motion of tall buildings under random disturbances such as wind pressures and small earthquakes. The main topics in this paper are: (1) the principle of the acceleration feedback algorithm, (2) the expected control performance, (3) the multi-modal control algorithm, (4) the observed performance of the applications using the algorithm.

Various epoxy monomers containing benzophenone (BP) groups were synthesized by reactions of potassium or lithium salts of BP derivatives with excess epichlorohydrin or epibromohydrin using tetrabutylammonium bromide (TBAB) as a phase transfer catalyst (PTC). The copolymerization of glycidyl 3-(piperidylcarbonyl)-2,5-norbornadiene-2-carboxylate (GPNC), which was prepared by the reaction of epichlorohydrin with potassium carboxylate of a norbornadiene (NBD) derivative using a PTC, and (glycidyloxy)benzophenone with phthalic anhydride (PAn) proceeded in 93% yield using TBAB as a catalyst in sulfolane at 100 C for 24 h to give self-photosensitizing polyester P-1 containing a pendant NBD moiety and a pendant 4-oxybenzophenone group. Copolymerizations of various epoxy monomers containing certain NBD moieties and BP groups with PAn produced corresponding polyesters with pendant NBD moieties and BP groups in good yields. The photochemical valence isomerizations of the NBD moieties and the photosensitizing isomeri...

Various epoxy monomers containing norbornadiene (NBD) moieties were prepared by reactions of potassium salts of NBD derivatives with excess epichlorohydrin using tetrabutylammonium bromide (TBAB) as a phase transfer catalyst. The copolymerization of glycidyl (3-phenyl-2,5-norbornadien-2-yl)carboxylate (GPNC) with phthalic anhydride (PAn) proceeded smoothly using TBAB as a catalyst in sulfolane at 100 °C for 24 h to give polyester P-1 containing pendant NBD moieties. Copolymerizations of various epoxy monomers containing certain NBD moieties with carboxylic anhydrides gave the corresponding NBD polyesters in good yields. The photochemical valence isomerizations of the NBD moieties in the polymers were carried out in the film state or in the solution. Rates of the isomerizations of some NBD moieties in the polymers were strongly enhanced by the addition of photosensitizers such as 4-(N,N-dimethylamino)benzophenone (DABP). The Tgs of the polyesters having NBD residues and stored thermal energy in the corresp...

In this paper, we have outlined the neurobiological basis of alcohol and drug dependence. The prevalence of drug dependence is a serious social problem in many countries, including Japan. This problem involves many background factors, including those pertaining to medical sciences, socio economics, and politics. First, we briefly describe the findings pertaining to psychotomimetic drugs as a model of schizophrenia. The biological pathogenesis of schizophrenic disorders is still unknown. The symptoms of methamphetamine (MAP) and phencyclidine (PCP) psychoses are very similar to those of schizophrenic disorders involving hallucination or delusion. PCP causes not only positive symptoms but also negative symptoms. Therefore, it has been considered as a more comprehensive model of schizophrenia than other drugs. Furthermore, amotivational syndrome, which is observed in patients with chronic cannabis and organic solvent dependence, is similar to the negative symptoms of schizophrenia. Understanding the neurobiological basis of drug dependence by using the molecular biological approach will provide an important clue for elucidating the mechanisms underlying schizophrenia and endogenous psychiatric disorders. Next, we discuss account for the neurobiological mechanisms underlying drug dependence. The reward system in the brain, which is common for all dependent drugs, has been explained, and the stages of addiction corresponding to the development of drug dependence have been discussed followed. In addition, we have discussed the epigenetics aspects of substance dependence, which is one of the hottest topics in psychiatric genetics. We expect that further studies of the mechanisms underlying drug dependence will aid in elucidating of the pathophysiology of various psychiatric diseases.

This paper discusses the optimization of the active-passive composite tuned mass damper which was recently proposed by the authors for the purpose of reducing response vibrations of building structures subjected to disturbance excitations such as wind pressures or earthquakes. The parameter optimization, control force reduction, control energy minimization are discussed under several different types of excitations. A harmonic excitation, a stationary white noise and a non-stationary random excitation such as earthquake are all considered for the derivation of formulae.

This paper discusses the eigenvalue problem of a nonlinear differential equation that governs the stability of a shear bending column under extremely large deformation. What is taken into consideration is the geometrical nonlinearity while the material is supposed to be linear. The reason of a superbly stable buckling behavior of a slender rubber bearing is physically explained by pointing out the analogy that is similar to the nonlinear wave propagation expressed in KdV equation. The nonlinear boundary condition and the nonlinear term of the differential equation cancel each other and make the associated eigenvalue rather constant. In other words, as far as the material is supposed to be linear, the column does not buckle no matter how large the deformation is. This theoretical prediction is experimentally verified and successfully applied to a base isolation system of a lightweight structure.

A new control strategy to improve a tuned mass damper (TMD) is developed for the vibration control of a large structure subjected to external disturbances. The feedback gain of the proposed algorithm is linear to the response acceleration of the primal system and it is optimized in the frequency domain under a harmonic excitation. According to this method both the feedback gain and the TMD parameters are optimized in the frequency domain and they are expressed in a set of closed form solutions. The performance of the proposed control method is discussed and compared with that of a passive TMD.

Acid diffusion during the post-exposure bake of chemically amplified resists (CARs) is a major contributing factor to line width roughness (LWR) and resolution limits at the 32 nm node and beyond. To overcome these limitations, non-CAR materials are becoming more attractive because acid diffusion is eliminated. We have therefore focused our effort on the synthesis of copolymers that have both a diacyldiazo side chain unit as well as a hexafluoroalcohol unit. This copolymer shows better contrast than that of copolymers containing lactone units due to their inhibition behavior. Furthermore, polymer blends containing hexafluoroalcohol groups show good 100 nm line and space patterning property for 193 nm lithography. This paper describes the design, synthesis, and characterization of these non-CARs, and thier improvement to photolithography.

ArF immersion lithography using water as a fluid medium enables production of 45 nm features. Extending immersion lithography to 32 nm or below requires increases in the refractive indices of the lens material, the immersion fluid, and the resist material. However, a material with a high refractive index generally also has high absorbance. In attempt to design a resist with high refractive index and low absorbance, we studied several types of sulfur-containing polymers and determined which sulfur groups increase the refractive index without increasing the absorbance at 193 nm. We describe new thioester and sulfone structures that enable high index with low absorbance. This chemistry has been exploited to produce polymers with a refractive index of 1.8 at 193 nm and an absorbance less than 1.4 mm-1. The compatibility of the sulfur functionality with chemically amplified imaging chemistry was demonstrated by printing at 193 nm.

The cell cycle-regulatory transcription factor E2F1 induces apoptosis of postmitotic neurons in developmental and pathological situations. E2F1 transcriptionally activates many proapoptotic genes including the cyclin-dependent protein kinase cell division cycle 2 (Cdc2). Necdin is a potent mitotic suppressor expressed predominantly in postmitotic neurons and interacts with E2F1 to suppress E2F1-mediated gene transcription. The necdin geneNDNis maternally imprinted and expressed only from the paternal allele. Deletion of the paternalNDNis implicated in the pathogenesis of Prader-Willi syndrome, a genomic imprinting-associated neurodevelopmental disorder. Here, we show that paternally expressed necdin represses E2F1-dependentcdc2gene transcription and attenuates apoptosis of postmitotic neurons. Necdin was abundantly expressed in differentiated cerebellar granule neurons (CGNs). Neuronal activity deprivation elevated the expression of both E2F1 and Cdc2 in primary CGNs prepared from mice at postnatal day 6, whereas the necdin levels remained unchanged. In chromatin immunoprecipitation analysis, endogenous necdin was associated with thecdc2promoter containing an E2F-binding site in activity-deprived CGNs. After activity deprivation, CGNs underwent apoptosis, which was augmented in those prepared from mice defective in the paternal Ndn allele (Ndn+m/−p). The levels ofcdc2mRNA, protein, and kinase activity were significantly higher in Ndn+m/−pCGNs than in wild-type CGNs under activity-deprived conditions. Furthermore, the populations of Cdc2-immunoreactive and apoptotic cells were increased in the cerebellumin vivoof Ndn+m/−pmice. These results suggest that endogenous necdin attenuates neuronal apoptosis by suppressing the E2F1–Cdc2 system.

The MAGE (melanoma antigen) family is characterized by a large conserved domain termed MAGE homology domain. Originally identified MAGE genes encoding tumor rejection antigens are expressed only in cancers and male germ cells. Necdin, which contains the MAGE homology domain, is highly expressed in postmitotic cells such as neurons and skeletal muscle cells. The human necdin gene NDN is transcribed only from the paternal allele through genomic imprinting, and its deficiency is implicated in the pathogenesis of the neurodevelopmental disorder Prader-Willi syndrome. Although over 30 MAGE genes have been identified in humans, fruit fly (Drosophila melanogaster) has only a single MAGE gene that encodes a protein similar to necdin homologous MAGE proteins. In this study, we analyzed the spatiotemporal expression patterns of MAGE mRNA and the encoded protein during fly development. Whole-mount embryo in situ hybridization analysis revealed that MAGE mRNA was highly expressed at the syncytial blastoderm stage and in the ventral and procephalic neurogenic regions of the ectoderm during gastrulation. In contrast, MAGE expression was nearly undetectable in postmitotic neurons of the central nervous system at late embryonic stages. During postembryonic neurogenesis, MAGE was highly expressed in neural stem cells (neuroblasts) and their progeny (ganglion mother cells and postmitotic neurons) at larval and pupal stages. MAGE was also expressed in postmitotic neurons including mushroom body neurons and retinal photoreceptors in adulthood. These results indicate that MAGE expression lasts throughout the postembryonic neurogenesis in Drosophila.

Parkinson's disease (PD) is the most common movement disorder characterized by dopaminergic dysfunction and degeneration. The cause of most PD cases is unknown, although postmortem studies have implicated the involvement of oxidative stress. The identification of familial PD-associated genes offers the opportunity to study mechanisms of PD pathogenesis in model organisms. Here, we show that DJ-1A, a Drosophila homologue of the familial PD-associated gene DJ-1, plays an essential role in oxidative stress response and neuronal maintenance. Inhibition of DJ-1A function through RNA interference (RNAi) results in cellular accumulation of reactive oxygen species, organismal hypersensitivity to oxidative stress, and dysfunction and degeneration of dopaminergic and photoreceptor neurons. To identify other genes that may interact with DJ-1A in regulating cell survival, we performed genetic interaction studies and identified components of the phosphatidylinositol 3-kinase (PI3K)/Akt-signaling pathway as specific modulators of DJ-1A RNAi-induced neurodegeneration. PI3K signaling suppresses DJ-1A RNAi phenotypes at least in part by reducing cellular reactive oxygen species levels. Consistent with the genetic interaction results, we also found reduced phosphorylation of Akt in DJ-1A RNAi animals, indicating an impairment of PI3K/Akt signaling by DJ-1A down-regulation. Together with recent findings in mammalian systems, these results implicate impairments of PI3K/Akt signaling and oxidative stress response in DJ-1-associated disease pathogenesis. We also observed impairment of PI3K/Akt signaling in the fly parkin model of PD, hinting at a common molecular event in the pathogenesis of PD. Manipulation of PI3K/Akt signaling may therefore offer therapeutic benefits for the treatment of PD.

A comparison study of single-, bi-, and tri-layer resist (SLR, BLR, and TLR, respectively) process was investigated. The goal of this study is to clarify the advantage of each process for the pattern transfer etching process. Conventional ArF photoresist and bottom anti-reflective coating process were applied to SLR. Novel silsesquioxane (SSQ) resist and spin-on organic hard mask (SOHM) were used for BLR process. The SSQ consists of siloxane backbone which contains three components, protective group, solubility control group, and higher silicon containing group to increase etch selectivity to SOHM. The main polymer in SOHM contains naphthalene type unit, for both anti-reflective and etch-durable properties. SOHM layer is highly cross-linked film with more than 85wt% carbon content which contributes to higher etch selectivity. A conventional ArF photoresist as an imaging layer, spin-on glass (SOG) as an intermediate layer, and the SOHM as a bottom layer were applied to TLR process. Multi-layer materials of each process were spin-coated on the stacks of cap-oxide/low-k/SiC on Si substrate and exposed with ArF 0.75NA scanner for 100nm line and space imaging. SLR showed better lithographic performance than BLR and TLR. However after pattern transfer etching process into SiOC layer, the different performance among each process has been observed. SLR process after pattern transfer etching showed severe surface roughness, striation and line width roughness (LWR). On the other hand, BLR and TLR showed significant improvement of pattern transfer performance. Multi-layer process can improve LWR during etching process.