Publications (16)10.74 Total impact
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Article: Effect of highly lipolyzed goat cheese on HL-60 human leukemia cells: antiproliferative activity and induction of apoptotic DNA damage.
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ABSTRACT: To establish cheese as a dairy product with health benefits, we embarked on examining the multifunctional role of cheeses, especially in the field of cancer prevention. The current study was designed to investigate whether different types of commercial goat cheeses may possess antiproliferative activity, using an HL-60 human promyelocytic leukemia cell line as a cancer cell model. Among 11 cheese extracts tested at 500μg/mL, 6 (Crottin de Chavignol, Pouligny Saint-Pierre, Chabichou du Poitou, Valencay, Kavli, and Sainte-Maure de Touraine) resulted in a significant decrease of cell viability, which is consistent with a decrease in viable cell number. Compared with the half-maximal inhibitory concentration (IC(50)) value of individual cheeses in cellular proliferation assays, the Pouligny Saint-Pierre extract showed strong inhibition. Incubation of cells in the presence of Pouligny Saint-Pierre extract resulted in induction of cellular morphological changes and apoptotic DNA fragmentation as well as expression of the active form of caspase-3 protein. Based on the quantification of the ratio of free fatty acids to triglycerides in different cheese samples, a significant correlation was detected between lipolytic ripeness and IC(50) values for antiproliferative capacity tested in HL-60 cells. Collectively, these results support a potential role of highly lipolyzed goat cheeses in the prevention of leukemic cell proliferation.Journal of Dairy Science 05/2012; 95(5):2248-60. · 2.56 Impact Factor -
Conference Proceeding: Constructing quantum network coding schemes from classical nonlinear protocols
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ABSTRACT: The k-pair problem in network coding theory asks to send k messages simultaneously between k source-target pairs over a directed acyclic graph. In a previous paper [ICALP 2009, Part I, pages 622-633] the present authors showed that if a classical k-pair problem is solvable by means of a linear coding scheme, then the quantum k-pair problem over the same graph is also solvable, provided that classical communication can be sent for free between any pair of nodes of the graph. Here we address the main case that remained open in our previous work, namely whether nonlinear classical network coding schemes can also give rise to quantum network coding schemes. This question is motivated by the fact that there are networks for which no linear solutions exist to the k-pair problem, whereas nonlinear solutions exist. In the present paper we overcome the limitation to linear protocols and describe a new communication protocol for perfect quantum network coding that improves over the previous one as follows: (i) the new protocol does not put any condition on the underlying classical coding scheme, that is, it can simulate nonlinear communication protocols as well, and (ii) the amount of classical communication sent in the protocol is significantly reduced.Information Theory Proceedings (ISIT), 2011 IEEE International Symposium on; 09/2011 -
Conference Proceeding: Wafer thinning, bonding, and interconnects induced local strain/stress in 3D-LSIs with fine-pitch high-density microbumps and through-Si vias
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ABSTRACT: Mechanical strain/stress and crystal defects are produced in extremely thin wafers (thickness ~10 μm) of 3D-LSIs not only during wafer thinning, but also after wafer bonding using fine-pitch, high-density microbumps and curing. Furthermore, the metal of through-Si via (TSV) and microbump not only becomes the cause of contamination, but also induces strain/stress (due to the difference in the co-efficient of thermal expansion (CTE) between Si and metal) in thinned Si substrate. X-ray photoelectron spectroscopy (XPS) results showed that the crystal quality of Si is highly deteriorated in the ultra-poly ground (UPG) surface after wafer thinning and stress relief. Micro-Raman spectroscopy (μRS) data revealed that a local tensile strain amount to 1.8 GPa was induced by 4×4 μm<sup>2</sup> square sized Si microbumps in 10 μm-thick LSI wafers after bonding and curing. We have noticed that this locally induced strain/stress caused more than 10% change in the ON current of p-MOS transistor. CuSn microbumps have also induced strain/stress at Si wafer surface, and it penetrates deeper for larger bump size and wider for smaller bump pitch.Electron Devices Meeting (IEDM), 2010 IEEE International; 01/2011 -
Conference Proceeding: A study on temperature-compensated hybrid substrates for surface acoustic wave filters
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ABSTRACT: A hybrid substrate, comprising a thin LiTaO<sub>3</sub> layer bonded to a low-coefficient-of-thermal-expansion support, can be used instead of a conventional LiTaO<sub>3</sub> bulk substrate to improve the temperature coefficient of frequency (TCF) of surface acoustic wave (SAW) devices. The use of a thinner LiTaO<sub>3</sub> layer will clearly reduce the TCF, but on the other hand, will also lead to large spurious responses in the filter characteristics. However, we report here that if the bottom of the LiTaO<sub>3</sub> layer is made sufficiently rough, the problem can be effectively mitigated. In addition, numerical calculations indicate that correct choice of the support material can further mitigate the spurious response. We found that glass was superior to silicon as the support material. A SAW filter comprising a rough-bottom LiTaO<sub>3</sub> layer only six-wavelengths thick bonded to a glass substrate exhibited spurious responses of just 0.5 dB, which is comparable to that obtained with a conventional LiTaO<sub>3</sub> bulk substrate. Thus, the combination of an appropriate substrate material and a rough-bottomed LiTaO<sub>3</sub> layer affords a SAW filter with small TCF and yet good response characteristics.Ultrasonics Symposium (IUS), 2010 IEEE; 11/2010 -
Conference Proceeding: Perfect quantum network communication protocol based on classical network coding
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ABSTRACT: This paper considers a problem of quantum communication between parties that are connected through a network of quantum channels. The model in this paper assumes that there is no prior entanglement shared among any of the parties, but that classical communication is free. The task is to perfectly transfer an unknown quantum state from a source subsystem to a target subsystem, where both source and target are formed by ordered sets of some of the nodes. It is proved that a lower bound of the rate at which this quantum communication task is possible is given by the classical min-cut max-flow theorem of network coding, where the capacities in question are the quantum capacities of the edges of the network.Information Theory Proceedings (ISIT), 2010 IEEE International Symposium on; 07/2010 -
Conference Proceeding: A hybrid substrate for a temperature-compensated surface acoustic wave filter
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ABSTRACT: A hybrid substrate that is appropriate for temperature compensation of a surface acoustic wave (SAW) filter is developed. A one-port SAW resonator was fabricated on the hybrid substrate to study its electronic characteristics and thermal stability. The spurious response originating from bulk wave reflection at the layer interface was found to be sufficiently small with a relatively thin piezoelectric layer. The minimum temperature coefficient of frequency (TCF) was -8.4 ppm/°C.Ultrasonics Symposium (IUS), 2009 IEEE International; 10/2009 -
Conference Proceeding: Development of acoustic optics tunable filter and its application to strain sensing system
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ABSTRACT: A highly accurate strain sensing system has been developed by combining an acoustic optic tunable filter (AOTF), an optical fiber, and fiber Bragg gratings (FBGs). The AOTF is composed of an interdigital transducer (IDT) to generate surface acoustic wave (SAW), a SAW guide, and polarization beam splitters (PBSs) for separating TE and TM modes from a light with both modes and optical waveguides consisting of a Li-diffused layer on a Y-X LiNbO<sub>3</sub> substrate. The AOTF outputs only the wavelength of light corresponding to the applied SAW frequency. The AOTF operates as an optical spectrum analyzer by applying the swept SAW frequency to the AOTF. A highly accurate strain sensing system has been contributed by combining the optical fiber, the fiber Bragg gratings (FBGs), and the AOTF used instead of a conventional optical spectrum analyzer. The each FBG has each period of the grating in the fiber. The only wavelength of the light corresponding to the period of grating of FBG reflects when the light with wide range wavelength is inputted. The AOTF measures the reflected wavelength. When the strain is applied to the FBG, the only reflected wavelength corresponding to the strained grating period of its FGB shifts. The strength of the strain can be obtained from the shift value of the wavelengths measured by the AOTF. The place, where the strain is received, can also be measured at the same time by setting up a lot of FBGs having different period of grating. The strain accuracy of 0.9 ppm was measured by using this method at the room temperature. But a temperature characteristic of the AOTF is not good, it is necessary to improve the temperature characteristic of this sensing system. Adopting additional FBGs for reference, measured accuracy of standard deviation of 0.63 pm was obtained under the temperature change from -20 to 70degC. This strain sensing system would be able to apply to monitoring or watching a fall of rock, a landslide, an earthquake, a vibration of a- building or a bridge, a trespasser, a water level of river, and so on.Applications of Ferroelectrics, 2009. ISAF 2009. 18th IEEE International Symposium on the; 09/2009 -
Conference Proceeding: Development of a novel Wafer-Level-Packaging technology using laminating process
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ABSTRACT: We have been developing a novel Wafer Level Packaging technology which has a possibility of lowering WLP cost drastically by applying some Jisso techniques to WLP manufacturing processes. In short, our idea is laminating a Cu wafer having Cu bumps to a Si wafer in which LSIs are formed with a nonconductive thermosetting resin. The process flow of the developed WLP technology is as follows; 1. Cu bump formation by wet etching of a Cu wafer (same shape with a Si wafer) 2. Ni/Au plating both on top of the Cu bumps and Al electrodes on Si wafer 3. NCF (Non Conductive Film) laminating to a bump side of the Cu wafer 4. Laminating (thermo compression bonding) of Cu and Si wafer after alignment 5. Re-distribution layer (RDL) formation by wet etching of the Cu wafer laminated with the Si wafer 6. PSR laminating, solder ball mounting, and dicing In this development, reducing wafer warpage after thermo compression bonding, reducing misalignment between the Cu bumps on the Cu wafer and the Al electrodes on the Si wafer generated during the laminating process, and achieving a good ohmic and highly reliable connection of the bump and the electrode are the biggest issues. As for the wafer warpage, we developed double sided laminating structure and process which enables to cancel the wafer warpage because of balancing thermal stress of both sides of Si wafer. The misalignment caused by the difference of the thermal expansion coefficient of Cu and Si was effectively reduced with an offset bump formation method conducted at lithography process, and the misalignment occurred during the laminating process was also reduced by improving handling of thin Cu wafer. As a result, the misalignment could be suppressed under 20 um and the fine pitch (<100 um) connection was achieved. In addition, excellent electrical properties (ohmic contact and high yield within a wafer) and reliability were realized by employing the Au-Au thermo compression bonding method which is enabled with Ni/Au elec- troless plating on the Al electrodes of the LSI and also on the top surface of the Cu bumps. Moreover, we developed a technique of removing the NCF on top of Cu bumps before thermo compression bonding because of avoiding a residual NCF existence at the interface of Au-Au connections. In this work, we evaluated two kinds of methods for removing NCF, plasma etching and improving NCF laminating conditions.Electronic Components and Technology Conference, 2009. ECTC 2009. 59th; 06/2009 -
Conference Proceeding: Small Photovoltaic Module with Rectangular Cells for Reducing Output Degradation Caused by Spot Dirt
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ABSTRACT: This paper reports the output degradation reduction when spot dirt adheres to a small photovoltaic module with rectangular cells. A small photovoltaic module of 13 W was applied to various electric systems. The module consisted of single crystal silicon photovoltaic cells. The effect of the output degradation was studied by changing the aspect ratio of the photovoltaic cell. It was also studied the effect by changing the photovoltaic cell connection applied to the module. Changing the aspect ratio of the photovoltaic cell used for the photovoltaic module results in suppression of the output degradation by 80% or less with 3% of spot dirt on the module areaTelecommunications Energy Conference, 2006. INTELEC '06. 28th Annual International; 10/2006 -
Conference Proceeding: Degradation of Output Characteristics of a Small Photovoltaic Module Due to Dirt Spots
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ABSTRACT: This paper reports the output degradation characteristics of a small photovoltaic cell when a dirt spot adheres to the surface. The 11 W photovoltaic module GT434 was applied to various electric systems. The module consists of 34 cells, cut to 1/4 the silicon single crystal photovoltaic cell of a square with one side measuring 103 mm. The photovoltaic output power was found to be reduced by 50% when a 3% dirt area was applied to the small module. The decrease in output power was shown to improve when the shape of the photovoltaic cell was changedTelecommunications Conference, 2005. INTELEC '05. Twenty-Seventh International; 10/2005 -
Article: Magnetic properties of Bi3Fe5O12 garnet
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ABSTRACT: Nonthermodynamical garnet Bi 3 Fe 5 O 12 was synthesized by direct epitaxial growth via vapor phase using a reactive ion beam sputtering technique. The lattice constant was 12.631 Å. The saturation magnetization of the film grown onto a substrate (a=12.495 Å) was 1500 G at room temperature. The uniaxial anisotropy energy was +7.2×10<sup>4</sup> erg/cm<sup>3</sup>. The conversion electron Mössbauer spectroscopy measurement indicates that the internal fields of 24d and 16a sites in the nearly lattice‐matched film were 420 and 490 kOe, respectively. The internal field of the 24d site was larger by 30 kOe than that in YIG. The angle between the direction of the internal field and the film normal was 34.8°.Journal of Applied Physics 06/1990; · 2.17 Impact Factor -
Article: Temperature dependence of nonlinear absorption in InP doping superlattices
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ABSTRACT: Absorptive optical nonlinearity in InP doping superlattices grown by vapor‐phase epitaxy is investigated in a 2–300 K temperature range. The absorption spectra have tails below InP band‐gap energy, caused by the Franz–Keldysh effect due to the internal electric field. The absorption tail is almost temperature independent. This means that the periodic electric potential in the doping superlattice, responsible for the nonlinearity, is unchanged across this temperature range. Nonlinear absorption is evaluated by the pump‐probe method. The large reduction in absorption coefficient is obtained even with a weak excitation light intensity. This enhancement in nonlinearity is due to prolongation of the excited‐carrier lifetime. Nonlinear absorption increases as temperature decreases. This is due to the temperature dependence of the carrier lifetime.Journal of Applied Physics 11/1988; · 2.17 Impact Factor -
Article: Nonlinear optical absorption in an n‐InGaAsP/p‐InP heterodoping superlattice
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ABSTRACT: Absorptive optical nonlinearity in an n‐InGaAsP/p‐InP heterodoping superlattice grown by vapor phase epitaxy is investigated. Although change in the absorption coefficient per an excited carrier obtained for the doping superlattice is comparable to that of bulk material, larger nonlinear absorption is induced by unit‐intensity light illumination. This enhancement is attributable to prolonged carrier recombination lifetime due to the separation of electrons and holes in space. The nonlinear absorption caused by accumulated photocarriers can be explained by the combination of two effects: blocking of direct band‐to‐band transition in real space (band filling effect), and change in probability of indirect transition in real space (Franz–Keldysh effect) due to a modified internal electric field.Applied Physics Letters 03/1988; · 3.84 Impact Factor -
Article: Integration of MODIS land and atmosphere products with a coupled-process model to estimate gross primary productivity and evapotranspiration from 1 km to global scales
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ABSTRACT: We propose the Breathing Earth System Simulator (BESS), an upscaling approach to quantify global gross primary productivity and evapotranspiration using MODIS with a spatial resolution of 1-5 km and a temporal resolution of 8 days. This effort is novel because it is the first system that harmonizes and utilizes MODIS Atmosphere and Land products on the same projection and spatial resolution over the global land. This enabled us to use the MODIS Atmosphere products to calculate atmospheric radiative transfer for visual and near infrared radiation wave bands. Then we coupled atmospheric and canopy radiative transfer processes, with models that computed leaf photosynthesis, stomatal conductance and transpiration on the sunlit and shaded portions of the vegetation and soil. At the annual time step, the mass and energy fluxes derived from BESS showed strong linear relations with measurements of solar irradiance (r(2) = 0.95, relative bias: 8%), gross primary productivity (r(2) = 0.86, relative bias: 5%) and evapotranspiration (r(2) = 0.86, relative bias: 15%) in data from 33 flux towers that cover seven plant functional types across arctic to tropical climatic zones. A sensitivity analysis revealed that the gross primary productivity and evapotranspiration computed in BESS were most sensitive to leaf area index and solar irradiance, respectively. We quantified the mean global terrestrial estimates of gross primary productivity and evapotranpiration between 2001 and 2003 as 118 +/- 26 PgC yr(-1) and 500 +/- 104 mm yr(-1) (equivalent to 63,000 +/- 13,100 km(3) yr(-1)), respectively. BESS-derived gross primary productivity and evapotranspiration estimates were consistent with the estimates from independent machine-learning, data-driven products, but the process-oriented structure has the advantage of diagnosing sensitivity of mechanisms. The process-based BESS is able to offer gridded biophysical variables everywhere from local to the total global land scales with an 8-day interval over multiple years.Global Biogeochemical Cycles. 25. -
Article: Integration of MODIS land and atmosphere products with a coupled-process model to estimate gross primary productivity and evapotranspiration from 1 km to global scales
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ABSTRACT: We propose the Breathing Earth System Simulator (BESS), an upscaling approach to quantify global gross primary productivity and evapotranspiration using MODIS with a spatial resolution of 1-5 km and a temporal resolution of 8 days. This effort is novel because it is the first system that harmonizes and utilizes MODIS Atmosphere and Land products on the same projection and spatial resolution over the global land. This enabled us to use the MODIS Atmosphere products to calculate atmospheric radiative transfer for visual and near infrared radiation wave bands. Then we coupled atmospheric and canopy radiative transfer processes, with models that computed leaf photosynthesis, stomatal conductance and transpiration on the sunlit and shaded portions of the vegetation and soil. At the annual time step, the mass and energy fluxes derived from BESS showed strong linear relations with measurements of solar irradiance (r(2) = 0.95, relative bias: 8%), gross primary productivity (r(2) = 0.86, relative bias: 5%) and evapotranspiration (r(2) = 0.86, relative bias: 15%) in data from 33 flux towers that cover seven plant functional types across arctic to tropical climatic zones. A sensitivity analysis revealed that the gross primary productivity and evapotranspiration computed in BESS were most sensitive to leaf area index and solar irradiance, respectively. We quantified the mean global terrestrial estimates of gross primary productivity and evapotranpiration between 2001 and 2003 as 118 +/- 26 PgC yr(-1) and 500 +/- 104 mm yr(-1) (equivalent to 63,000 +/- 13,100 km(3) yr(-1)), respectively. BESS-derived gross primary productivity and evapotranspiration estimates were consistent with the estimates from independent machine-learning, data-driven products, but the process-oriented structure has the advantage of diagnosing sensitivity of mechanisms. The process-based BESS is able to offer gridded biophysical variables everywhere from local to the total global land scales with an 8-day interval over multiple years.Global Biogeochemical Cycles. 25:B4017-B4017. -
Article: Integration of MODIS land and atmosphere products with a coupled-process model to estimate gross primary productivity and evapotranspiration from 1 km to global scales
[show abstract] [hide abstract]
ABSTRACT: We propose the Breathing Earth System Simulator (BESS), an upscaling approach to quantify global gross primary productivity and evapotranspiration using MODIS with a spatial resolution of 1-5 km and a temporal resolution of 8 days. This effort is novel because it is the first system that harmonizes and utilizes MODIS Atmosphere and Land products on the same projection and spatial resolution over the global land. This enabled us to use the MODIS Atmosphere products to calculate atmospheric radiative transfer for visual and near infrared radiation wave bands. Then we coupled atmospheric and canopy radiative transfer processes, with models that computed leaf photosynthesis, stomatal conductance and transpiration on the sunlit and shaded portions of the vegetation and soil. At the annual time step, the mass and energy fluxes derived from BESS showed strong linear relations with measurements of solar irradiance (r(2) = 0.95, relative bias: 8%), gross primary productivity (r(2) = 0.86, relative bias: 5%) and evapotranspiration (r(2) = 0.86, relative bias: 15%) in data from 33 flux towers that cover seven plant functional types across arctic to tropical climatic zones. A sensitivity analysis revealed that the gross primary productivity and evapotranspiration computed in BESS were most sensitive to leaf area index and solar irradiance, respectively. We quantified the mean global terrestrial estimates of gross primary productivity and evapotranpiration between 2001 and 2003 as 118 +/- 26 PgC yr(-1) and 500 +/- 104 mm yr(-1) (equivalent to 63,000 +/- 13,100 km(3) yr(-1)), respectively. BESS-derived gross primary productivity and evapotranspiration estimates were consistent with the estimates from independent machine-learning, data-driven products, but the process-oriented structure has the advantage of diagnosing sensitivity of mechanisms. The process-based BESS is able to offer gridded biophysical variables everywhere from local to the total global land scales with an 8-day interval over multiple years.Global Biogeochemical Cycles. 25:B4017-B4017.
